Monetary Policy and the Stock Market Dissertation

Monetary Policy and the Stock Market - Dissertation Example One financial instrument that is normally used by governments is the issuance of treasury bills or government bonds wherein the earning interest rates will generally be followed by the banks of that country. By using the interest rates that will define the treasury-bill holder’s earnings will slowly influence the financial market to adjust its interest rates. In the absence of other economic indicators, the treasury-bill interest rates will not only be adopted by the banks in their own financial transactions but it will also be used as the bench mark for the amount of money that will be available to borrowers. In theory, if the interest rates are low more people will borrow money from the banks. If the interest rates are high, the theory sustains that little to no borrower will loan money from the banks and most economic activity will be financed from in-house sources. Other instruments or means of conducting monetary policy includes making the government as the lender of last resort wherein the government will be the source of funds that will be available to borrowers normally a function provided by banks and other financial institutions. Another means of conducting monetary policy includes changing the reserve requirements in banks in order for them to operate. Another is where the government announces its intent to reduce or control inflation or by simply indicating the interest rates it wants for the money it intends to loan out. And last but not the least is moral suasions.... Meanwhile the true value of money is dependent on several factors such as the actual value of the goods that can be bought by the money or its value as compared with other currencies. However, given that these factors are also dependent on other economic indicators such as inflation and the volume of foreign currency reserve a country has, the correlation of the monetary policy of a country with its interest rates, stock market performance, and inflation will be explored by this paper. Monetary policy is implemented by increasing or decreasing the interest rates that is in theory would be able to inversely increase or decrease the supply of currency in circulation. In fine, the monetary policy of a country controls the amount or volume of currency in circulation to stimulate growth or maintain the stability of its economy. The primary onus of a government’s monetary authority is to create the optimal monetary policy that will stabilize prices for its basic commodities and enco urage investment. The trick however is how to make banks and other financial institutions follow the interest rates the government’s monetary authorities’ desires. One financial instrument that is normally used by governments is the issuance of treasury bills or government bonds wherein the earning interest rates will generally be followed by the banks of that country. By using the interest rates that will define the treasury-bill holder’s earnings will slowly influence the financial market to adjust its interest rates. In the absence of other economic indicators, the treasury-bill interest rates will not only be adopted by the banks in their own financial transactions but it will also be

Claudius Speech - Hamlet Essay Example for Free

Claudius Speech Hamlet Essay Claudius, the former ruler, husband of his sister and brother of the recently perished king gives a speech at the beginning of Act I. II of Hamlet. Shakespeare’s use of literary devices allows the reader to comprehend the intentions behind Claudius’s figurative language within his coronation speech. The opening scene in Hamlet portrays Denmark to currently be critically unstable and with militaristic chaos; however, in Claudius’s speech he disposes that idea and conveys confidence in the stability of the nation. This chronological set up introduces the theme of appearance vs.  reality as Claudius efforts to manipulate the kingdom into trusting that he has everything under control is carried mischievously yet successfully throughout his speech. Aware of the presence of the rightful king, young Hamlet, Claudius commences his speech with an ambiguous line that strikes the attention of Hamlet. Once he is aware of young Hamlet’s attention, he continues to approach the courthouse. He seemingly shows a state of grief as he acknowledges his dead brother. â€Å" My dear brother’s death† the use of alliteration makes us aware that Claudius has used that line several times before in order to show a sign of loss. He wants to appear that has suffered too from this death, he mentions that â€Å" the memory be green† this metaphor is placed to represent the idea that the memory is fresh and it has not been long since he perished, while also leaving a gruesome image of the old kings decomposing body. His first use of anti-thesis is then exposed in line 6, when he mentions â€Å" the wisest sorrows† in that line he is understanding those in grief but reminding them to think of themselves and the future of Denmark instead. After respectfully mentioning the death of Hamlet, and expressing his condolence to the kingdom he deceitfully moves on to the second important announcement: his wedding. Uneasy, Claudius is trying to go about his speech like a metaphorical obstacle course hoping there is no interference or opposition, while still being able to appear as confident. Efficaciously, he presents his marriage â€Å" Therefore our sometime sister, now our queen, Th’ imperial jointress to this warlike state. † Using the state of war as his alaby to the marriage of his brother’s wife he is able to convince the courthouse that it is for the greater good and that his actions are a form of self-sacrifice for the nation. Continuing to justify his marriage as a cause and affect matrimony instead of acts of incest he mentions the â€Å" mirth in funeral † and â€Å"dirge in marriage†. This literary device is important within his speech because it is his second antithesis, and a paradoxical clause. In this he is suggesting that he brought happiness to this sad event for the benefit of his people. â€Å"In equal scale, weighing delight and dole† Claudius is trying to banish the aura of unsteadiness and declares balance. He makes up for the sorrow of his dead brother, by marrying his sister. Even though it is an obvious unusual event, Claudius reflects enough confidence as king and successfully manages avoid any opposition. A good strategy used was his the frequent use of â€Å" we†. This indicated that the king was not only speaking for himself, but he was speaking for everyone like a good statesman would. In reality however, he was doing so to make everyone aware that it was of â€Å" better wisdoms† to agree with him, and that those with worst wisdoms would not face good consequences. Claudius gently expresses his supreme control over Denmark and threatens anyone who dares oppose him in a non-aggressive way. He later finalizes the topic of marriage by dismissing the awkward topic of the table like a typical political â€Å" For all, our thanks† As king, Claudius then addresses the issues with Norway. Assertively, he informs the kingdom of his plan of action. He repeats the line â€Å" dear brother’s death† giving it little sentimental value. He then quickly states that Norway believes that Denmark is â€Å" disjoint and out of frame. † He assures the courthouse that the case is not so, and that they will successfully deal with Fortibras. The irony behind that is that Denmark is weak, regardless of what Claudius wants his people to believe. In order to seem like a man of action Claudius puts his future plan forward â€Å" Thus much the business is we have here writ to Norway, uncle of young Fortibras. † By doing that he convinces many that he is a potent king. Writing to Norway makes him seem like he is aware of what he is doing and that the nation does not need to worry. To complement his assurance he appoints two messengers to deliver a letter, this is significantly important because his objective is to prove to the court that he trusts his officials, ironically thought, he is purposely sending two people incase of a betrayal. Claudius’s speech had a successful outcome. He was able to gently hide his inner insecurities and expose himself as a good statesman and valiant leader. His word usage was essential to the deliverance of his speech as it allowed him to get his awkward points across like unusual marriage to his sister. His use of antithesis did make the reader question the sincerity of his grief, but it did not seem to affect the opinion of the courthouse. He showed clear superiority over everyone within the courthouse, especially Hamlet, while making himself clear that he would not tolerate any disagreement of his coronation. Most importantly, he put an action plan forward and proved himself as king.

Free College Essays - Tone, Allusions and Diction in Hawthornes The Scarlet Letter :: Scarlet Letter essays

The Scarlet Letter - Use of Tone, Allusions and Diction Puritans are well known for their morality in discipline, religious intolerance, and harsh punishments for those defying their beliefs. These Puritan influences had a great impact on early American literature. Nathaniel Hawthorne provides an illustrated look into the Puritans and their community in his classic The Scarlet Letter. Through Hawthorne's use of tone, allusions with Hester and Dimmesdale, and the diction that is used to describe how the village behaves during the multiple scaffold scenes he provides a disapproval for these rigid moralists' extreme way of life. Hawthorne's use of tone has revealed his feelings regarding the Puritans. He starts out relatively early in the book describing these people as "being of the most intolerant brood" (86) unveiling at once the lack of understanding they had. Finding out about Hester and Pearl, the village at once "scorned them in their hearts, and...reviled them with their tongues" (86) exposing to us the discriminating disposition that the Puritans have for those who were not exactly like them or followed their rules. The tone that is inferred from the harsh words allows us to see the negative attitude that the narrator feels for these Protestants. Along with the tone of "voice" that we can almost hear speak to us with Nathaniel Hawthorne's rich yet somewhat chilling vocabulary is the allusion among the Puritans and their influence. As the Puritans could see that the "same scorching stigma was on them both!" (225), Nathaniel Hawthorne alluded to the same marks on the crucified Christ, disclosing how scornful the convictions by the Puritans were. As he discusses the generations to come of puritanical influence, Hawthorne sees them wearing "the blackest shade of Puritanism" (211). This allusion allows us to see the perniciousness that flourished inside of the Puritans and how it was carried on from one generation to another. The allusions displaying the author's feelings of the religious intolerance of the Puritans are further developed with his choice of diction during the scaffold scenes. The Puritans' feelings were so lacking of compassion that "they were stern enough to look upon her death†¦without a murmur†¦ but had none of the heartlessness of another social state." (53). This implied that when faced with death of a betrayer they would not have a reaction because their commiseration was completely devoted towards social applications.

Journal of the Plague Year and Frankenstein

The Plague and Frankenstein The quest for knowledge is eternal and almost never-ending. People devote their lives to studying and advancing their knowledge, but their advancement is always held in check by society and the people who studied before them. Several novels have been written which explore the effect knowledge and its limitations can have on society. This paper will focus on Defoe’s Journal of the Plague Year, and Mary Shelley’s Frankenstein or the Modern Prometheus. Even though these two novels were written about 100 years apart, they still exemplify many aspects as to why knowledge has limitations. While Defoe’s Journal centers on how to prevent and cure the plague, with a heavy emphasis on religion, Shelley’s Frankenstein has little to no religious affiliation, and focuses on how science and knowledge can potentially lead to evil and misfortune. The plague was a severe and devastating disease which affected Europe multiple times throughout history; each time killing every person who came down with the disease. People are fortunate enough today to have a cure for this disease, but during the 1700s, there was no cure and very little knowledge about proper medical practices. Defoe mentions how signs were posted throughout London, claiming of people who knew of a cure or treatment for the plague, however some of these treatments â€Å"prepared their bodies for the plague, instead of preserving them against it. †1 Thieves and pick-pockets robbed and cheated poor people out of their money with scams, sometimes even poisoning their victims with tonics or â€Å"physicks† that could include such poisons as Mercury in them. These scammers were all throughout the city, appealing to the desires and abundance of the poor. There was no regulation of such business practices and advertisements made ridiculous claims of free help, only to deceive the poor once they got there, forcing them to pay for what may (or may not) help them. These practices were quite cruel and unjust, but people were so scared for their lives that they were willing to do anything which would allow them to live. Not every person in the city fell victim to these scams. Many people once they heard news that the plague had reached London decided to flee and head to some far off town where they might be able to avoid catching the disease. This plight from the city was not only a rational decision, but a religious one as well. Much debate between people in London was sparked about the religious justification for staying in the city, and trusting in God to protect them where they were, or to leave London and â€Å"trust God with [their] safety and health†. 3 For the main character in this novel, H. F. struggles with this decision because he can leave London and live with his relatives, and risk losing all of his possessions, but he ultimately decides to stay, viewing his decision as remaining faithful to God. Upon informing his brother of this decision, he learns that the person, who he was going to entrust with his property during his leave, became ill with the plague, only enforcing H. F. ’s feelings that he made the correct decision to stay in God’s faith. 4 Once the plague hit London with full force, the city was forced to find a new way in which to contain this disease. Instead of looking to the filth with which people lived in, and regarding that it could be carried by animals such as rats, the town determined that each house was to be inspected by doctors, and if the plague should be found within a home, the inhabitants would be locked inside the house, only to come out if they died or the disease had passed. Each home which the plague was found in had a red cross painted on the door, marking it for all to see, and a Watchman was assigned to make sure nobody went in or out of the house, and to run errands for the family if need be. This cruel idea caused many families to parish in their own homes, while others tried to escape by either sneaking out or attacking/threatening the watchmen. In the book Frankenstein or the Modern Prometheus, by Mary Shelley, the underlying theme is how knowledge and power can lead to misery and destruction. In the book, Victor Frankenstein goes off to college and becomes obsessed with several different types of philoso phy and science. He becomes absorbed in â€Å"the secret of life† and he ultimately tries to recreate it. He is successful and brings life to a monster so hideous that even he cannot bear to be around. Frankenstein tries to desert the monster which he created, but he is never fully able to, as the monster follows and spies on Frankenstein and kills part of his family. Frankenstein is appalled that his creation could have begun to cause such horror and pain to people around him, but is worried that if he tells anyone about the monster which he has created, then he himself will look like a madman. The monster himself is eager for affection from humans, but everywhere he goes, he is shunned and forced away from the town due to people being in fear of him. The monster spends much time watching the actions of a family of peasants, where from his hiding place he is able to learn how to speak French as well as read. After some time he ultimately decides that they are a very compassionate family and that he should reveal himself to them, upon doing this, they are disgusted and chase him away. The monster vows to get revenge on Frankenstein and first begins by killing his little brother whom he stumbles across in the forest in Geneva. He then plants the child’s necklace on a friend of Victor’s, to make her appear as the murderer. She is tried for the crime and hung for it. The monster realizes that his only chance for happiness lies within Frankenstein creating him a female companion. He persuades Frankenstein to create him a female saying that he will leave mankind alone forever and go live in some distant land if he has a companion to go with him. 7 As Frankenstein has begun work on his second monster in Scotland, he is reminded of how crazy he became when creating his first monster, and upon catching a glimpse of his monster watching him through the window, Frankenstein freaks out, and destroys the second body which he is creating. The monster upon seeing this is enraged and promises to kill the rest of Frankenstein’s friends and family. This promise holds true, for Frankenstein loses his best friend that night, his wife on his wedding night, and his father. Rather than heed to the monster’s wishes and create a wife for him, Frankenstein was overcome with the guilt of the deaths of his monsters first two victims. He worries that in creating another, he will be creating a duo of evil that will wreak havoc upon the human race. For it was his fault in the first place which let his imagination get a hold of himself and he wanted to create life for himself. This intense lust for knowledge which Frankenstein has ultimately leads to his demise. He becomes mad in his quest and ends up destroying everyone dear to him as well as himself in the end. Both The Journal of the Plague Year and Frankenstein or the Modern Prometheus have heavy themes about knowledge. Defoe’s Journal specifically focuses on how disease was treated and what the methods were to try to cure it. The Journal also has a heavy religious force in it as well. The people in the story as well as the main characters, look towards Bible versus and quotes for guidance in their decision making. This is not the same as in Frankenstein where the main character becomes god-like himself with his creation of life. This major difference is most likely due to the fact that the novels were written about 100 years apart from each other and people’s views how religion affected their daily lives had greatly changed. There is very little mentioned in Frankenstein about religion at all. In each novel, there is excess knowledge than what people have the capacity for; therefore in The Journal, London makes the harsh decision to lock people in their own homes in order to prevent the spread of the plague; while in Frankenstein, his ever persistent quest for knowledge winds up killing him and those dearest to him. The novels are almost a warning as to what effect knowledge can have on society and suggest, that as Socrates said, â€Å"the only true wisdom is in knowing you know nothing. †

Evaluation of instructional materials Essay

Introduction As a teacher, it is your responsibility not just to teach but to guarantee that the students are learning and you must create an active and motivating learning experience for the students. The Worldwide web gives choices of wide variety of instructional resources that you could use as your teaching tool. In choosing instructional materials, the teacher must consider not just its availability or the ease of use but more on its learning outcomes. An instructional resource should meet the purpose and the objectives of the lessons and flexible to the students’ differences such as ability, interests and learning style. The objectives, the students, learning environment and the availability of the resources are some factors to consider in choosing an instructional material (Morton, 2003). Design â€Å"The content is accurate, logical and well organized, objectives are clearly defined, and the content helps to achieve the necessary objectives. † The resource should be well planned and concrete to maximize the available learning materials and to save time. The objectives should be attainable with regards to the students ‘grade level making sure that after the instructional process, learning outcomes are anticipated. It should foster critical thinking, problem-solving and decision-making (Alto). â€Å"Examples are meaningful and helpful, questions are presented clearly. † Ease of communication is important so that the students would easily grasp the information or ideas relayed by the teacher. â€Å"Important points are emphasized, the amount of information presented is comfortable and the instructional material is free of gender, race, religion or ethnicity bias. Media elements fairly represent composition of career fields in terms of gender and race. † It is also important to consider the cultural backgrounds of each student. Each student has the right for equality in learning therefore the teacher should make some adjustments to the students with different customs from the rest of the class. † Information is clear and current, facts come from reliable source which are clearly define. † Instructional technologies should be incorporated in the learning experience to enhance student understanding. Digital libraries, computational tools, virtual environments, modeling and visualization and connectivity are among the up-to-date learning process that students should be familiar of. â€Å"Content moves learners beyond the basics and encourage high level of thinking, students are engaged in applying what they learn. Lay-out is consistent. † The projects should have relevant application that the student will look forward to make after the learning process. â€Å"The Content is culturally diverse; product accommodates unique learning styles and various ability levels. Assessment methods are challenging, appropriate and suitable to learning goals. † The instructional materials should be appropriate to student differences such as interest, ability and learning style. â€Å"Teachers can easily assess students’ progress by evaluating the outcomes provided within the product, reading level is appropriate for target audience and the product is suitable for the age and grade level. † The evidence of learning should be evaluated as to determine the extent to which the goal and objectives are achieved. The development process, the reliability of implementation, the students learning as well as the teacher development should be attained. Procedures Students must make the most of his or her senses such as touch, sight, auditory, and smell in doing activities that will develop not just the intrapersonal learning but the interpersonal development as well. Interaction among students will make the learning process easier and more enjoyable and the teacher must have the means of motivating the students in order for them to finish the activity, instruction or the discussion. Clarity Readings and visual aids should be able to attract the attention and interest of the students. The teacher should have user-friendly visual aid that will further enhance the students’ imagination and thinking. Computer softwares have options for making the presentation more attractive such as colorful backgrounds, animations and sound effects that will be helpful for the students learning process. Efficiency Instructions should focus on the topic to avoid confusions to the students and maximize the time allotted for the learning process. Too much information could lead to â€Å"information overload† that the student will tend to disengage from the learning process. Instructional Material Evaluation. I chose to use the preschool program of the HighReach for they guaranteed that the programs are aligned with the states and federal standards. Moreover, they clearly stated and specified their objectives as to what learning skills they intend to develop upon the students.They also have programs that will develop not just the intrapersonal development but also the interpersonal learning. Works cited: Alto, P. Designing Learning Space Project- Designing a Preschool Highschool [Electronic Version]. Morton, D. J. B. (2003). Selecting and Using Instructional resources to Enhance Instruction [Electronic Version].

How to Make Silver Polishing Dip

How to Make Silver Polishing Dip As silver oxidizes, it will tarnish. This layer of oxidation can be removed without polishing and scrubbing by simply dipping your silver in this non-toxic electrochemical dip. Another big advantage to using a dip is that the liquid can reach places a polishing cloth cannot. This is an easy experiment and takes mere minutes! Silver Polish Ingredients Sink or glass panHot waterBaking sodaSaltAluminum foilTarnished silver How to Remove Silver Tarnish Line the bottom of the sink or a glass baking dish with a sheet of aluminum foil.Fill the foil-lined container with steaming hot water.Add salt (sodium chloride) and baking soda (sodium bicarbonate) to the water. Some recipes call for 2 teaspoons of baking soda and 1 teaspoon of salt, whereas others call for 2 tablespoons each of baking soda and salt. No need to measure the amounts - just add a bit of each substance.Drop the silver items into the container so they are touching each other and resting on the foil. You will be able to watch the tarnish disappear.Leave heavily tarnished items in the solution for as long as 5 minutes. Otherwise, remove the silver when it appears clean.Rinse the silver with water and gently buff it dry with a soft towel.Ideally, you should store your silver in a low-humidity environment. You can place a container of activated charcoal or a piece of chalk in the storage area to minimize future tarnish. Tips for Success Use care when polishing or dipping silver plated items. It is easy to wear away the thin layer of silver and cause more harm than good through over-cleaning.Minimize exposing your silver to substances that contain sulfur (e.g., mayonnaise, eggs, mustard, onions, latex, wool) because the sulfur will cause corrosion.Using your silver flatware/holloware or wearing silver jewelry helps to keep it free from tarnish.

Lieutenant General James Gavin in World War II

Lieutenant General James Gavin in World War II James Maurice Gavin was born March 22, 1907, in Brooklyn, NY as James Nally Ryan. The son of Katherine and Thomas Ryan, he was placed in the Convent of Mercy orphanage at age two. After a brief stay, he was adopted by Martin and Mary Gavin from Mount Carmel, PA. A coal miner, Martin barely earned enough to make ends meet and James went to work at age twelve to help the family. Wishing to avoid a life as a miner, Gavin ran away to New York in March 1924. Contacting the Gavins to inform them that he was safe, he began looking for work in the city. Enlisted Career Late that month, Gavin met with a recruiter from the US Army. Underage, Gavin was unable to enlist without parental consent. Knowing this would not be forthcoming, he told the recruiter he was an orphan. Formally entering the army on April 1, 1924, Gavin was assigned to Panama where he would receive his basic training in his unit. Posted to the US Coastal Artillery at Fort Sherman, Gavin was an avid reader and an exemplary soldier. Encouraged by his first sergeant to attend a military school in Belize, Gavin received outstanding grades and was selected to test for West Point. Rising in the Ranks Entering West Point in the fall of 1925, Gavin found that he lacked the basic education of most of his peers. To compensate, he rose early each morning and studied to make up the deficiency. Graduating in 1929, he was commissioned as a second lieutenant and posted to Camp Harry J. Jones in Arizona. Proving to be a gifted officer, Gavin was selected to attend the Infantry School at Fort Benning, GA. There he trained under the guidance of Colonels George C. Marshall and Joseph Stillwell. Key among the lessons he learned there was not to give long written orders but rather to provide subordinates with guidelines to execute as the situation warranted. Working to develop his personal style of command, Gavin was happy in the schools educational environment. Graduating, he wished to avoid a training assignment and was sent to the 28th 29th Infantry at Fort Sill, OK in 1933. Continuing his studies on his own, he was particularly interested in the work of British World War I veteran Major General J.F.C. Fuller.   Three years later, in 1936, Gavin was sent to the Philippines. During his tour in the islands, he became increasingly concerned about the US Armys ability to withstand Japanese aggression in the region and commented on his mens poor equipment. Returning in 1938, he was promoted to captain and moved through several peacetime assignments before being posted to teach at West Point. In this role, he studied the early campaigns of World War II, most notably the German Blitzkrieg. He also became increasingly interested in airborne operations, believing them to be the wave of the future. Acting on this, he volunteered for the Airborne in May 1941. A New Style of War Graduating from the Airborne School in August 1941, Gavin was sent to an experimental unit before being given command of C Company, 503rd Parachute Infantry Battalion. In this role, Gavins friends convinced Major General William C. Lee, commander of the school, to allow the young officer to develop the tactics of airborne warfare. Lee agreed and made Gavin his Operations and Training Officer. This was accompanied by a promotion to major that October. Studying other nations airborne operations and adding his own thoughts, Gavin soon produced FM 31-30: Tactics and Technique of Air-Borne Troops. World War II Following the attack on Pearl Harbor and US entry into the conflict, Gavin was sent through the condensed course at the Command and General Staff College. Returning to the Provisional Airborne Group, he was soon dispatched to aid in converting the 82nd Infantry Division into the US Armys first airborne force. In August 1942, he was given command of the 505th Parachute Infantry Regiment and promoted to colonel. A hands-on officer, Gavin personally oversaw the training of his men and endured the same hardships. Selected to take part in the invasion of Sicily, the 82nd shipped out for North Africa in April 1943. Dropping with his men on the night of July 9/10, Gavin found himself 30 miles from his drop zone due to high winds and pilot error. Gathering up elements of his command, he went without sleep for 60 hours and made a successful stand on Biazza Ridge against German forces. For his action, the 82nds commander, ​​Major General Matthew Ridgway, recommended him for the Distinguished Service Cross. With the island secured, Gavins regiment aided in holding the Allied perimeter at Salerno that September. Always willing to fight beside his men, Gavin became known as the Jumping General and for his trademark M1 Garand. The following month, Gavin was promoted to brigadier general and made assistant division commander. In this role, he aided in planning the airborne component of Operation Overlord. Again jumping with his men, he landed in France on June 6, 1944, near St. Mà ©re Église. Over the next 33 days, he saw action as the division fought for the bridges over the Merderet River. In the wake of the D-Day operations, the Allied airborne divisions were reorganized into the First Allied Airborne Army. In this new organization, Ridgway was given command of the XVIII Airborne Corps, while Gavin was promoted to command the 82nd. That September, Gavins division took part in Operation Market-Garden. Landing near Nijmegen, Netherlands, they seized bridges in that town and Grave. In the course of the fighting, he oversaw an amphibious assault to secure the Nijmegen bridge. Promoted to major general, Gavin became the youngest man to hold that rank and command a division during the war. That December, Gavin was in temporary command of the XVIII Airborne Corps during the opening days of the Battle of the Bulge. Rushing the 82nd and 101st Airborne Divisions to the front, he deployed the former in the Staveloet-St. Vith salient and the latter at Bastogne. Upon Ridgways return from England, Gavin returned to the 82nd and led the division through the wars final months. Later Career An opponent of segregation in the US Army, Gavin oversaw the integration of the all-black 555th Parachute Infantry Battalion into the 82nd after the war. He remained with the division until March 1948. Moving through several high-level postings, he served as assistant chief of staff for operations and Chief of Research and Development with the rank of lieutenant general. In these positions, he contributed to the discussions which led to the Pentomic Division as well as advocated for a strong military force that was adapted to mobile warfare. This cavalry concept ultimately led to the Howze Board and influenced the US Armys development of helicopter-borne forces. While comfortable on the battlefield, Gavin disliked the politics of Washington and was critical of his former commander- now president- Dwight D. Eisenhower, who wished to scale back conventional forces in favor of nuclear weapons. He likewise butted heads with the Joint Chiefs of Staff regarding their role in directing operations. Though approved for promotion to General with the assignment to command the Seventh Army in Europe, Gavin retired in 1958 stating, I wont compromise my principles, and I wont go along with the Pentagon system. Taking a position with the consulting firm Arthur D. Little, Inc., Gavin remained in the private sector until serving as President John F. Kennedys ambassador to France from 1961-1962. Sent to Vietnam in 1967, he returned believing the war to be a mistake that distracted the US from the Cold War with the Soviet Union. Retiring in 1977, Gavin died on February 23, 1990, and was buried at West Point. Selected Sources PA History: James Gavin New York Times: James Gavin Obituary World War II Database: James Gavin

Understanding the Ballot Initiative Process

Understanding the Ballot Initiative Process The ballot initiative, a form of direct democracy, is the process through which citizens exercise the power to place measures otherwise considered by state legislatures or local governments on statewide and local ballots for a public vote. Successful ballot initiatives can create, change or repeal state and local laws, or amend state constitutions and local charters. Ballot initiatives can also be used simply to force state or local legislative bodies to consider the subject of the initiative. As of 2016, the ballot initiative process was used at the state level in 24 states and the District of Columbia and is commonly used in county and city government. The first documented approval for the use of the ballot initiative process by a state legislature appeared in the first constitution of Georgia, ratified in 1777.   The State of Oregon recorded the first use of the modern ballot initiative process in 1902. A major feature of the American Progressive Era from the 1890s to 1920s, the use of ballot initiatives quickly spread to several other states. The first attempt to gain the approval of the ballot initiative at the federal government level took place in 1907 when House Joint Resolution 44 was introduced by Rep. Elmer Fulton of Oklahoma. The resolution never came to a vote in the full House of Representatives, having failed to gain committee approval. Two similar resolutions introduced in 1977 were also unsuccessful.According to the Initiative Referendum Institutes Ballotwatch, a total of 2,314 ballot initiatives appeared on state ballots between 1904 and 2009, of which 942 (41%) were approved. The ballot initiative process is also commonly used at the county and city levels of government. There is no ballot initiative process at the national level. Adoption of a nationwide federal ballot initiative process would require an amendment to the U.S. Constitution. Direct and Indirect Ballot Initiatives Ballot initiatives may be either direct or indirect. In a direct ballot initiative, the proposed measure is placed directly on the ballot after being submitted by a certified petition. Under the less common indirect initiative, the proposed measure is placed on a ballot for a  popular vote only if it has first been rejected by the state legislature. Laws specifying the number and qualifications of names required to place an initiative on a ballot vary from state-to-state. Difference Between Ballot Initiatives and Referendums The term ballot initiative should not be confused with referendum, which is a measure referred to voters by a state legislature proposing that specific legislation may be approved or rejected by the legislature. Referendums may be either binding or non-binding referendums. In a binding referendum, the state legislature is forced by law to abide by the vote of the people. In a non-binding referendum, it is not. The terms referendum, proposition and ballot initiative are often used interchangeably. Examples of Ballot Initiatives Some notable examples of ballot initiatives voted on in  the November 2010 midterm elections included: Washington State Initiative 1098 would impose a first-ever state income tax, initially on individuals with incomes above $200,000 but later possibly extend to other groups at the legislatures discretion. This action would remove Washington from the list of nine states without a state income tax.Californias Proposition 23 would suspend enforcement of the sweeping California Global Warming Act and all laws related to it until the states unemployment rate eases and becomes stable.A ballot initiative in Massachusetts would  slash the states sales tax from 6.25 percent to 3 percent, and repeal in most cases the state sales tax on alcoholic beverages.Californias Proposition 19 would legalize the possession, cultivation, and transportation of marijuana for the personal use of persons 21 years of age or older.As a sign of opposition to the new federal health care reform law, voters in Arizona, Colorado, and Oklahoma considered ballot initiatives affirming individuals choices on purchasing insurance or participating in government plans.

Level of service of safety (critical review) Essay

Level of service of safety (critical review) - Essay Example This is because, there are many accidents that occur in different roads, but he rural or two lane roads remain unattended and not maintained to the standard of safety that is required for a standard road. In the analysis of the highways as the report portrays, rural; roads or two lane roads are more prone to increased road accidents and fatalities at both low and high range AADT due to their design. Therefore, the report is authentic enough and treats the problem in detail, and might be put into practice by road design professionals. Kononov and Allery (60) argues that a road safety analysis has to include the analysis of the severity of accidents and their numbers, while a second approach has to be based on the injury and the fatal accidents only. The safety of a road network has to largely indicate the number of accidents per year or and the number of fatalities and injury that result from such accidents or the AADT. It is through these factors that are ad might be classified to be either safe or unsafe in regard to road transportation. These are the important factors hat are considered when marking out black spots or areas with a higher number of road accidents and fatalities per year. Though as Kononov and Alley (60) elaborate most super highways are designed within standards, there exists dispersion where accidents are more prone and more fatal compared to other sections. These sections or black spots as they are often referred are unidentified though such data and engineers are able to verify and redesign such sections of roads to enhance the level of safety and impact a better safety performance function. A report financed by the European Union on road safety management (14) establishes the steps that have to be included in road network safety management. Theses steps are the data collection on traffic, roads and accident

Writing Truly Is Re-Writing Personal Statement Example | Topics and Well Written Essays - 750 words

Writing Truly Is Re-Writing - Personal Statement Example The exercises are particularly interesting because they cater to arousing critical thinking. I have to be more aware of everything that may indicate something in the comprehension of the text. It requires more than just shallow reading or scanning through the words. It is very much like being a detective and looking through the words to find out clues to solve a mystery. Critical thinking was among my favorite task to do because it is particularly interesting as it stimulates the brain. I have learned to be analytical in figuring out what the paper is all about and in trying to make sense of all that I read. The hardest part is trying to put thought into the paper. This, I learned, is an arduous task that requires time and effort. Writing truly is re-writing. The way that I see it, even the best of writers have editors. Being accepting of criticism and taking what you have learned from it to apply it in the future is the true measure of humility. Because it is next to impossible to say that your own piece of writing is perfect. If anything, to say so is either downright arrogant or foolish. Others are born with the talent to write and they only need very little editing as it comes naturally. But I have learned that it is also something that can be acquired. The secret to this is organization. One must first organize his thought as they may not make sense at first glimpse.  

Homeland Security Essay Example | Topics and Well Written Essays - 750 words

Homeland Security - Essay Example This essay, this reaction paper, will argue that these terms need to be defined very specifically and very deliberately; otherwise, it persists as a vague concept capable of being used as justification for nearly any action. More specifically, this paper will argue that homeland ought to be defined to include a variety of harmonious interests and that security ought to be defined as actions and policies designed to accomplish their objectives with the least amount of intrusion into the affairs of individual states and into the lives of individuals or businesses. As an initial matter, homeland should include a variety of interests; more particularly, it should refer to the nation, the states, and to individuals. There should be no ranking of these homeland types in terms of significance; that means that national interests should not be placed above state interests through this extra-constitutional concept, and that individuals should not be granted a higher status than they are already accorded under traditional notions of constitutional jurisprudence. A framework for allocating powers and rights already exists in the constitution; the mere notion of a recently defined homeland being promulgated in haphazard fashion and zealously guarded sounds forebodingly like an attempt to subvert constitutional principles through non-constitutional means. A great deal has been made about protecting critical homeland sites, such as those related to infrastructure, finance, and military readiness. The homeland also includes lesser constituent parts of the country, such as in Louisiana, which were devastated by the hurricanes recently. There ought to be a uniform approach to defining the homeland, whether is the Pentagon, the Federal Reserve Bank, Louisiana, or Mr. and Mrs. Smith's family farm. My sense, my reaction, is that the homeland portion of the concept prioritizes national aspects while minimizing or ignoring state and individual aspects. This would be a dangerous deviation from the constitutional principles upon which this country was founded; as a result, that would make Homeland Security a direct threat to the system of governance established by the American constitution. In addition, the security aspect of the concept is also vague and seemingly unlimited. Is security meant to be proactive or reactive Is it meant to stifle otherwise protected types of speech and protests in order to prevent some potential negative outcome The Central Intelligence Agency and the American military have traditionally been vested with duties dealing with international affairs. The CIA is no more allowed to spy on American soil than are American soldiers allowed to engage in domestic law enforcement activities. And, yet, as security implies both the gathering of intelligence and the mobilization of physical forces to deter any potential attack, whom else would be involved in maintaining American security if not these organizations This raises troubling issues. Does this notion of security mean

Product Life Cycle Management Essay Example | Topics and Well Written Essays - 4500 words

Product Life Cycle Management - Essay Example Secondly, to explore how PLM could help in different stages of Computer Aided Design (CAD) design or where PLM could contribute and involve in a new product development. This paper also incorporates the case studies of PLM and how adoption of PLM has helped SMEs to secure an established position in the industry. The project analyzes important studies and then conducts a primary survey that centers on SMEs adoption of PLM. The results of the studies have confirmed the conclusion that the SMEs have grown with the acceptance of new sophisticated technologies. PLM strategy is a solution addressing many components for managing product data (Kemmerer, 1999) and provides the necessary requirements and capabilities companies need to successfully manage information and facilitate communication and collaboration across the entire product lifecycle from idea through retirement [PTC n.d. ]. In fact, PLM is the extension of PDM (Abramovici and Sieg, 2002) which appeared during 1980s. With the advent of Computer Aided Design (CAD) solutions, engineering design entered a new era. Parallel with the continued development of Computer -Aided Design and Manufacturing and Engineering (CAD/CAM/CAE) tools, Product lifecycle management (PLM) is the crucial business approach that assigns a constant set of business solutions on behalf of the cooperative establishment, management, distribution, and application of product definition orientation across the extended business from abstraction to edge of life and it is now clearly acknowledged by many firms as basic to the product innovation evolution, and a corporation's top-notch and fundamental accomplishment (Stark, 2003, 4) PLM is the method of managing a firm's products all the way across their life cycles in the most effective way. If the firms start losing control over its products, then it will lead to adverse effects. A product does not exist when it is at its development stage. That is the time when it becomes difficult to manage. This is practically the reason why there is a need to completely involve PLM in the process so as to be sure that the product would make a good introduction and growth within the industry that it is involved with. Penetrating the industry totally is not that easy, this is a truth even for those products whose brands have already been established in the market.1 Hence, to be able to assure that a particular business product or service would make it to the competition, the administrators of the company should know about how to use PLM cycle effectively for their own product or service's popularity in the market probably resulting to more improved rate of profit returns. Ho wever, it could be noticed too that as the introduction of the product is launched, the management as to how to retain its effect in the market is what should be given attention next. As soon as existence of a product is ensured, the problem of managing that product arises. With the advent of PLM, the products are able to reach the market fast and better support from the customer's side is guaranteed. It is necessary to bring a product into the market otherwise; one firm will lose the customers to other firm. The fact that competition is tough in the market, being the first one to introduce a new product is an important part of the process.2 This fact is a special

ROWE Program at Best Buy Essay Example | Topics and Well Written Essays - 1000 words

ROWE Program at Best Buy - Essay Example Plachy & Plachy (1998) also confirms that ROWE assists managers to design feasible ways of improving their output. Best Buy, for instance, is an international company that applies the ROWE program. This paper, in effect, explores ROWE program at Best Bay using various subheadings. Culture of Best Buy Best Buy Co., Inc. is an international electronic retailer that majorly sells in the United States, Mexico, United Kingdom, Turkey, China, and Canada. As an important aspect of the culture in Best Buy, the organization holds close social media as a form of empowering its employees. In other words, the company reaps massive productive gain through proper application of social media. Gibson & Billings (2003) points out three important social media tools applied in Best Buy. The Loop Marketplace, as one tool, involves replacing traditional suggestion box, where employees submit and share ideas, with specific market meeting points. Instead of collecting opinions of customers using suggestion boxes, the company identifies specific marketplaces where customers could converge and air out their views. As a second tool, Best Buy applies the Prediction Market tool to predict future market behaviors. Through prediction strategy, the organization designs suitable ways of controlling both supply and price of its products. The third social media tool the company has productively implemented is the Blue Shirt Nation. The latter tool involves diverting focus from improvement of pension schemes to modification of IT systems. Application of modern technological advancements has created a work environment where both employees and employers could freely interact. Approach to Organizational Change that ROWE Program Illustrates Gibson & Billings (2003) asserts that Best Buy has transformed its workplace by demolishing old systems where physical presence of a worker is equated to productivity of the worker. That is, from the name of the program, â€Å"results-only work environment,† Best Buy has focused on productivity of an employee, as an organizational change. Delmont (2005) also supports that the program in Best Buy objects at judging performance of a workforce on its output instead of duration spent in a meeting or in an office. Practically, ROWE program allows employees in the company to enter and exit their workplaces at any time of the day. There is no penalty or fine to an employee arriving after the official opening hours or leaving before the official business hours. Delmont (2005) summarizes that the program perceives work as something to do but not somewhere to go. The company is, therefore, interested in knowing whether work is satisfactorily completed. Through ROWE program, two major positive outcomes have been felt in the company. Overall employee satisfactory has shoot up following improvement in every department. Also report by Gallup, an organization that audits corporate cultures, indicates that the company’s productivity has climb ed up by 35% (Delmont, 2005). Resistance ROWE program at Best Buy Faces Even though ROWE program has significant effects in improvement of overall productivity of an organization and employees satisfaction, it, however, faces certain challenges. Resistance often comes from staffs members who appear to be

Mail Order Bride Essay Example | Topics and Well Written Essays - 1500 words

Mail Order Bride - Essay Example The mail order brides generally belong to second and third world countries such as Ukraine, Russia, Colombia, Mexico, Philippines, Africa, India, and Malaysia, however, some mail order brides also belong to first world nations such as Sweden, Japan, and Canada. The husbands generally belong to the developed nations such as United States, Canada, United Kingdom, and Australia. At present about 150,000 potential spouses advertize on the internet. The males who advertise their intend to marry someone in another country are known as mail order grooms (Wikipedia). The first process is the tradiational process which involves preparation of actual paper catalogues by the prospective brides and advertizing them in magazines such as Car and Driver, Stereo Review, and Rolling Stone, to get men to order them. These paper catalogues are distributed world wide through the maganizes (Ho). The scond process is the more recent one in which the women are solicited by an agency through a newspaper advertisement and their catalogues are advertized on the internet. However, in this process there is an inherent assumption by the advertisers that the women who apply belong to economically challenged classes, so there are cases of exploitation by the husbands in this process (Ho). Once the women is accepted by the agency, she undergoes a rigourous screening process which includes an in-depth questionnaire. The prospective mail order brides are interviewed on the basis of various factors including physical appearance, family background, eduction, work experience and other character refrences. However, apart form asking about themselves they are also asked about their desired match (groom) in oreder to make a perfect match. After the woman has successfully qualified all the screening rounds, the agency reviews her choices and looks for a suitable groom. In recent times the mail order bride business has gained momentum due to the increase in emmigration to developed nations from developing nations. Presently there are more than 200 agencies having operations in mail order business in the US. The companies in this business generate margins by charging both the counterparts for their communiactions and also for the services provided (Ho). Current size of the Mail Order Bride Business in the US Currently, there are more than 400 companies operating this business in the US (as compared to 200 such agencies under operation in 1996) and the revenue generated is more than $500,000 annually. The main target markets for mail order brides are the developing countries like Philippines, Former USSR and other Asian countries. In 2002, there were several thousand Filipina mail order brides in Canada and more than 5,000 such brides arrived to North America annually (MCCLELLAND, 2002). Also, currently there are over one million women from the former USSR who desire to become mail order brides for foreign men (MailOrderBrides.com). Also according to one of the web-sites there are more than 100 new profiles added each week (Bridesbymail). The main reason for targeting these markets is the stereotype of the women in these nations, as most of the women in these nations are known to be submissive, loyal, soft spoken and

ROWE Program at Best Buy Essay Example | Topics and Well Written Essays - 1000 words

ROWE Program at Best Buy - Essay Example Plachy & Plachy (1998) also confirms that ROWE assists managers to design feasible ways of improving their output. Best Buy, for instance, is an international company that applies the ROWE program. This paper, in effect, explores ROWE program at Best Bay using various subheadings. Culture of Best Buy Best Buy Co., Inc. is an international electronic retailer that majorly sells in the United States, Mexico, United Kingdom, Turkey, China, and Canada. As an important aspect of the culture in Best Buy, the organization holds close social media as a form of empowering its employees. In other words, the company reaps massive productive gain through proper application of social media. Gibson & Billings (2003) points out three important social media tools applied in Best Buy. The Loop Marketplace, as one tool, involves replacing traditional suggestion box, where employees submit and share ideas, with specific market meeting points. Instead of collecting opinions of customers using suggestion boxes, the company identifies specific marketplaces where customers could converge and air out their views. As a second tool, Best Buy applies the Prediction Market tool to predict future market behaviors. Through prediction strategy, the organization designs suitable ways of controlling both supply and price of its products. The third social media tool the company has productively implemented is the Blue Shirt Nation. The latter tool involves diverting focus from improvement of pension schemes to modification of IT systems. Application of modern technological advancements has created a work environment where both employees and employers could freely interact. Approach to Organizational Change that ROWE Program Illustrates Gibson & Billings (2003) asserts that Best Buy has transformed its workplace by demolishing old systems where physical presence of a worker is equated to productivity of the worker. That is, from the name of the program, â€Å"results-only work environment,† Best Buy has focused on productivity of an employee, as an organizational change. Delmont (2005) also supports that the program in Best Buy objects at judging performance of a workforce on its output instead of duration spent in a meeting or in an office. Practically, ROWE program allows employees in the company to enter and exit their workplaces at any time of the day. There is no penalty or fine to an employee arriving after the official opening hours or leaving before the official business hours. Delmont (2005) summarizes that the program perceives work as something to do but not somewhere to go. The company is, therefore, interested in knowing whether work is satisfactorily completed. Through ROWE program, two major positive outcomes have been felt in the company. Overall employee satisfactory has shoot up following improvement in every department. Also report by Gallup, an organization that audits corporate cultures, indicates that the company’s productivity has climb ed up by 35% (Delmont, 2005). Resistance ROWE program at Best Buy Faces Even though ROWE program has significant effects in improvement of overall productivity of an organization and employees satisfaction, it, however, faces certain challenges. Resistance often comes from staffs members who appear to be

The dinosaur ridge in colorado Assignment Example | Topics and Well Written Essays - 500 words

The dinosaur ridge in colorado - Assignment Example useum where a road slices through a mountain where dinosaur footprints, bones and fossils of pre historic plants and insects are etched by nature into the scraped rock walls. There were a lot of foreign visitors and local families drawn by the amazing sites, with kids hugging the giant footprints as if feeling the spirit of the pre historic beast. The guide is keen to educate the visitors. According to him, some of the best known dinosaurs, diplodocus, stegosaurus, allosaurus, and Apatosaurus were discovered here in the late 1800s. The main entrance of the museum has the fake models of these dinosaurs, which are just thrilling to observe. Though the museum is not as large as one expects after reading about it on the internet, the experience of having to ride on the old rickety mini-bus, the well-versed tour guides and the touching of the bones and the dinosaur tracks on display makes the tour amazing. The place has a great history as the guides made us discover. There is a mountain on the side whose surface looks like the surface of mars, which according to the guides is what the earth looked like back in the dinosaur days. It is gray, hard and crusty and surrounded by the treasures of fossils that made the geologists and paleontologists to have the site designated as a natural landmark in order to preserve the fossils in 1989. The guides refer to the tracks as the dinosaur freeway. Though they do not reveal the details of the dinosaurs, they are the most popular and spectacular parts of the ridge. The mysterious faint prints, massive and three toes announce the earthly presence of the dinosaurs. In most cases, one will find children staring at the mother and baby footprints perhaps wondering how big the dinosaur young ones could have been. According to the guides, the ridge also has interpretive signs at the trail locations, which explain local geology, trace fossils, paleo-ecology, a volcanic ash bed and how economically, coal, oil and clay have developed

Association football and soccer Essay Example for Free

Association football and soccer Essay Soccer is the world’s most popular sport. It is the national sport of most European and Latin-American countries and many other nations. Millions of people in more than 140 countries play soccer. Soccer is one of the most famous international sports. There are three distinct reasons that soccer is so widely popular. I- Soccer is a relatively easy game to learn and play. II- It provides many physical benefits and III- Has the ability to benefit cultures by bringing countries together. I- Soccer is an easy game to learn. Many children start to play the game around the age of three. Actually, as soon as most kids learn to walk they learn to kick a ball around which is a key component of soccer. Very little equipment is needed to play soccer. This adds to its accessibility to the masses. All that is needed to play the game of soccer is a soccer ball, shin guards, and goalie equipment. A soccer game may be played either indoors or outside. It is played on a rectangular field with a goal net on each short side of the field. A soccer team is comprised of 11 players. All players must hit the ball with their feet or body and only the goalie is allowed to touch the ball with his or her hands. A soccer game begins with a kick off en the center of the field. A coin is flipped to decide which team will kickoff. The other team kicks of at the start of the second half. At this time the teams also switch sides or nets. After a team scores the other team gets to kickoff to begin play again. The kickoff takes place in the middle of the field. When the ball is kicked it must travel the circumference of the ball and touch another player before the kicker can touch the ball again. After the ball is in play it remains in play unless it crosses a goal line or a touch line. All players attempt to stop the ball from coming in there zone while at the same time trying to score a goal. A player may kick the ball into the net with any part of the body except the hands and arms. If the ball goes out of bounds the play is restarted with a corner kick, a goal kick, or a throw-in. The referee decides what type to use. If the ball crosses the goal line and the defensive team touched it last then there is a corner kick by the offense. If the offense touches the ball last and crosses the goal line then it is a goal kick. A throw in happens when the ball crosses the touch line. When it crosses the touch line the team that did not touch it last throws the ball in bounds. The ball is thrown over their head with two hands. Fouls are called when a player does not obey the rules and acts unsportsmanlike. When a foul is called the opposite team receives a either a penalty kick, a direct free kick or and indirect free kick. Although, it may sound complex, very young children are able to learn the game quite easily. II- Soccer is a good sport to play if you like to stay physically fit. There are many exercises that are required for the soccer player to be at their peak performance. Exercises that strengthen your legs and improve flexibility are ideal. Physical conditioning is important if you plan on being good at soccer. Here are five important exercises I will discuss that are ideal for soccer: 1. Running: running helps to improve cardiovascular fitness. In soccer there is lots of running for the ball so endurance and a speed is a must. 2. Leg Extension: using weights can help strengthen the legs. Using weights makes you kick harder and makes the ball travel farther; as a result you become a better player. 3. Leg Machines: exercising all muscles in the leg makes you kick harder and prevents injury when you are diving all over for the ball. The strong muscles help prevent injuries. 4. Stretching: stretching allows you to be more flexible. Sometimes soccer players need to kick the ball in the most awkward positions. Flexibly helps the player to kick the ball in those positions more effectively. 5. Weight Training: all around weight training makes a soccer player even better. A stronger body helps prevent injury and improve all around performance. Practice helps the soccer player become more skillful and physically fit. Soccer drills like dribbling the ball and head butting add to a players endurance and physical agility. Soccer can be a very demanding sport. A players strength, flexibility, and overall physical condition is put to the test. Soccer players are able to stay healthy, strong, and obtain â€Å"life long† fitness due to their preparation and participation in the game. Another added benefit is the stress relief that is found in participating in a strenuous sport such as soccer. III- Lastly, soccer has the ability to be a great unifier. Soccer can be a unifier of countries, their people, and spirit. In every society and culture, there are many things in common and many differences but there is one thing that links us all. The link is the world of sports. Sports are a way of life in many nations and cultures. There are many types of sports, but there is one sport that is known in every corner of the world. This sport is soccer. Soccer is a sport that is played in every continent in the world; it is the one and only sport without borders. Millions of people watch soccer, which is why people know other cultures. I am from Pakistan. Our national game is field hockey, but everybody prefers to watch cricket. I remember in the year 1992 when Pakistan won the first and only world cup of cricket. Everybody praised the team because they were the heroes of the nation. After two years, in 1994, Pakistan had four world cups in four different sports: field hockey, cricket, snooker and squash. After that, Pakistan never won another world cup in any sport till now. In the 1999 cricket world cup final Pakistan suffered a humiliating defeat by the Australians that disheartened the people. After a bad 2003 world cup performance, Pakistanis took less interest in cricket and took more interest in soccer. Now days most people prefer to watch soccer, even though Pakistan does not have a soccer team that plays an international game. Why do I like soccer? The main reason is the passion and the thrill of the game. Millions of soccer fans like me like soccer because of tactics: how the player tackles ball, how they make moves, how they use skills. The more skillful the soccer player the better. That’s my life experience. Now I watch soccer more than cricket. It takes less time to watch and it is an interesting game. My cousins and friends are also fans of soccer. We are all fans of different teams and players. We all watch mostly European Leagues such as English Premier League, UEFA Cup etc. Why those leagues? We prefer these leagues because the clubs pay high prices to buy world class players to play for the clubs. Those leagues play every year. We have a craze for soccer. When we watch games how we support the team or players we like, wearing the shirts, shouting and even praying for them. Soccer has the ability to unify  us as a people, to unify our hearts and minds. When I was over there, and even here, when I talk to someone we always talk about soccer. My opinion is that soccer affects the Pakistani culture very much. How does soccer affect the culture of the United States? Outside the United States and Canada the game of soccer is called football. Soccer is very popular among American youth and has the most professional players out of any nation in the world. Chuck Klosterman in â€Å"George Will vs Nick Hornby† writes â€Å"Soccer will soon become part of the fabric of this country and will be as popular as any other game here. † â€Å"According to the Soccer Industry Council of America, soccer is the No. 1 youth participation sport in USA. There are more than 3. 6 million players under the age of nineteen registered to play and that number has been expanding at over 8 percent a year since 1900†. Those are going to be a fans, players, referees, coaches etc. for the future of United States Soccer. His favor is a critic. Klosterman criticizes soccer in â€Å"George Will vs Nick Horby. † He says we will never care about soccer in United States because soccer is inherently un-American, is it Outcast Culture. He also mentions is most that children do not love soccer. Most youth soccer players end up joining the debate team before they turn fifteen. Youth do not like soccer the way it is played. He compares soccer with baseball. Baseball is most common sport played by youths. He wonders why we care that soccer is the most popular game on the earth and is played by millions of people. To love soccer is to say you believe in enforced equality more than you believe in the value of competition and the capacity of the human spirit. I disagree with his criticism of soccer because most people like soccer. Why did the soccer star David Beckham come here to teach soccer? Why does America have a soccer team play in almost every World Cup? I agree that soccer is not as common as other games, but still people play soccer here. In fact, the biggest reason for soccers failure in the United States is that it doesnt conform easily to the demands of television. The reason soccer isnt as popular in the US is not because it isnt physical enough. I play and I know for certain that it is, and I used to live in US. I just recently moved to Pakistan in Asia. I used to watch soccer all the time, of course it was international soccer, but I watched it on ESPN sports. Soccer hasnt reached its peak in the US, to be frank. I see people beginning to take interest in it. Of course, the most unrecognized form of soccer is womens soccer, but that is a different subject all together. The reason is because the major US sports Baseball, Football (Rugby) , Basketball seasons take up the entire year. I think there may be 1-2 days in a year where none of the sports is played. Also, the major sports cover everything that soccer does, scoring in a net NBA, physical roughness NFL Football, hitting an object MLB. The major US sports had already established themselves in the US, so there is not really a good entry point for soccer. In conclusion, you can see that I am crazy about soccer. It is a sport that is very easy to learn and takes very little money to participate in. It is a sport that can easily get a person into top physical shape and develop â€Å"life long† fitness. But most importantly, it is a sport that allows many countries to become unified through their love of the game. That is why I love soccer.

Symbolism Of Illusion In The Glass Menagerie

Symbolism Of Illusion In The Glass Menagerie Illusion is the most important word in the thematic and symbolic organisation of the play, The Glass Menagerie. Williams wastes no time in pointing out the illusions that are important in the play. The stage directions tell us that transparent walls create the illusion of an apartment building, while music and coloured lights suggest a dance hall across the alley. The fire escape that leads into and out of the Wingfields apartment only seems to provide an escape from what Williams calls the slow and implacable fires of human desperation. Several times Tom comments directly to us that America in the 1930s believed that the worlds trouble were not important enough to worry about. The young people though that change and adventure were possible in their lives only through hot swing music and liquor, dance halls, bars, and movies, and sex. But, in truth, the world in the 1930s was not waiting for the sunrise, according to the popular song; it was waiting for the bombardments of the Second World War. As Williams takes us inside the Wingfields apartment and the lives to his characters, he reveals more illusions and he shows how his characters use them and respond to them. To avoid the unpleasant truth of her familys present and probable future condition, Toms mother, Amanda, cherishes several illusions. She believes that she still has the charm she once had as a young girl in Blue Mountain, and she treasures the memory of having received seventeen gentlemen callers one Sunday afternoon, any one of whom she could have married. She believes that her children are bound to succeed since they are just full of natural endowments. The fact is that Tom is close t losing his job at the warehouse, has decided to become a merchant seaman, yet really wants to be a writer. Toms sitter, Laura, suffers from acute shyness, is lame, and seems interested only in caring for her collection of glass animals and listening to old phonograph records. It is typical of Amandas desperate clinging to illusio n that she believes Laura can be happy and successful is she goes to business college and learns to type. It is almost painful for us to watch Amanda convince herself that the gentleman caller Tom has invited for supper is a remarkable young man who will be a fine suitor for Laura. She believes that if she makes Laura look pretty and attractive, if she alters one of her old dresses to wear herself, shines up the three remaining pieces of wedding silver, recovers the furniture, gets a new lamp, and if she herself plays the role of a charming, youthful Southern matron, Lauras gentleman caller will be so captivated that he will become a frequent caller and will eventually marry Laura. The fact is that Him OConnor is only an average fellow, whose moments of popularity and success are fading memories of high school days. He seems to feel sorry for Laura as a brother might rather than enamoured of her as a suitor. What is more, Jim is engaged and when he makes his announcement, Amandas il lusion is smashed. While Him OConnor temporarily becomes an illusion of Lauras salvation in Amandas mind, Jim also has illusions. He has created them in order to believe in a happy and successful future. Jim has faced the fact that he has not achieved the success everyone in high school expected of him, but he believes that he can still capture it. By taking a course in public speaking and thereby gaining social poise, he is certain that with his brains and ability he will be fitted for an executive position. He also believes that by taking a course in radio engineering he will be able to get in on the ground floor of the television industry and go right to the top of the ladder of success. Jims buoyant self-confidence, native sincerity, and boyish insensitivity to many of the things going on around him help him to create his illusions. The various generalizations that he proclaims about life, himself, and other people provide him with a protective cloak but the cloak may well turn out to be threadbare as time passes. Laura, shy and withdrawn as she is, also has illusions. She believes that, when she was in high school and wore a brace on her leg, everyone used to watch her when she was late for chorus practice and had to go clumping to her seat in the back row of the auditorium. In explaining her agonized self consciousness, she tells Jim that, to her, the clumping sounded like thunder. Of course, Jim never even noticed. When Laura talks to Jim about her favouite glass animal, a unicorn, she is really talking about herself. She develops her illusion by saying that the unicorn loves the light, may feel lonesome being different from the other animals, but does not complain about it and get along nicely with the horses that do not have horns. She also says that all of her glass animals like a change of scenery to the movies or to the Jewel-box, where they raise the tropical flowers, instead of going to her classes at business college. When the unicorn falls from the table and loses his horn, Laura s ays that she will imagine that the unicorn had an operation, that the horn was removed to make the unicorn feel less freakish. Similarly, in her brief time with Jim, during which they talk, dance, and kiss, Laura apparently feels less freakish. To explain why Jim has been beyond her reach, Laura has imagined that Jim married Emily Meisenbach. When she learns that he did not, Laura hopes that Jim will call on her again or ask her for a date. Her momentary hope is destroyed, however, when Jim announces that he is going steady with a girl named Betty and that they are in love. Although she has illusions, Laura, nevertheless, seems to have accepted what she is and what life has offered to her. She does not try to gloss over or deny the ways things are as Amanda does. She does not project a happy and successful future for herself, as Jim does for himself. Nor does she quarrel with the way things are, as Tom does. Like the animals in her glass menagerie, Laura remains delicate and vulnerable. In her own way she is hard, as glass is hard, and just as easily damaged if not protected, but she also possesses beauty as fine glass does and an inner light of varying shades of colour. With his apparently clear view of the facts around him. Tom seems, at first, to have not illusions. He believes that by joining the Union of Mrechant Seamen he will even escape the fanciful views and pretensions that others have. As a traveler, he will experience change and adventure first-hand and so dispel what he regards as the harmful illusions about life and the world that surround him in his family and in society. At the end of the play, however, Tom admits that he has been pursued by the memory of his sisters fragile existence. His escape itself was an illusion, and he discovers that he has been more faithful to Laura than he intended to be by continuing to remember and appreciate the fragile, the delicate, the beautiful things that Laura appreciates and comes to represent. Since the play itself and the characters are so obviously immersed in illusions, what is the truth that Tim Wingfield in his opening speech promises to reveal? What is Tennessee Williams theme in The Glass Menagerie? Illusions are deceptions, misinterpretations of the facts, and so would appear to be things to avoid, to be rid of; yet at the same time it is impossible for human beings to escape them. Williams shows us clearly that the various illusions the characters have are their means of coping with the facts of their lives. However foolish and silly their illusions may seem, all of the characters would suffer, perhaps even be broken, if they did not have them. Without pretense and self-deception, Amanda would have no self-confidence or hope for the future remaining after his failure to approach the success people had believed he would have. Laura would wither and die because she could not identify with anything, nor see beauty, delicacy, and truth in small, fragile, even commonpl ace things. Tom would nor escape because he could not hope to experience change and adventure. Unquestionably, illusions are potent things! But Williams does not say that illusions are necessarily better or more pleasant than facts. Just as facts can produce heartache and anguish knowing the clear truth about someone or something can sometimes be unbearable illusions, too, can bring sorrow and pain. Amandas are painful to Tom. Lauras and Toms are painful to Amanda, but perhaps the saddest illusion of all in the play is the one that prompts Tom to say good-bye to Laura. She is a reminder to Tom of an illusion-filled past that impeded his growth by obscuring his view of the way things truly are. To grow and to see things clearly, he had to leave. Moreover, when he says Nowadays the world is lit by lightning, Tim means that the world must be seen not in the soft, delicately flickering candle flame that is Laura but in the electric, dynamic illumination of a force beyond human influence. The force, manifest in lightning, is inexorable, and it blots out any candle flame. A glowing light, soft colour, or nostalgic sound or a shy, lame sister who appreciates such things has no place in the busy and insensitive world Tom sees around him. This belief, which is both Toms and the worlds, is, however, an illusion. That it is an illusion is shown by the very existence of the play. Tennessee Williams shows us that illusions, though hazardous, provide shelter from the hard facts of life. If we, like Tom, earnestly desire to escape the shelter and know these facts truly, we may have to give up out willingness to recognize and preserve the delicacy and beauty in life. This sacrifice may haunt us as it does Tom, but, according to Williams, the belief that we and the world must and will permanently say good-bye to all that Laura is and represents is itself an illusion-a sad deception.

The Goals of the Declaration of Independence Essay -- Essays Papers

The Goals of the Declaration of Independence The American Revolution was not only a battle between the British and the colonists; it was a historical movement that brought about new ways of thinking. The ideas of liberty and equality began to be seen as essential to the growth of the new nation. The separation of the American colonies from the British Empire occurred for a number of reasons. These reasons are illustrated in the Declaration of Independence. Although Thomas Jefferson wrote the document, it expressed the desire of the heart of each colonist to be free of British rule. British rule over the colonies became unbearable in the early months of 1776, making it clear to the colonists that it was time to either give in to British power or declare their independence. This idea of independence divided the colonies, but it was not long before a revolutionary committee met in Philadelphia and drew up the document that would change American history. The Declaration of Independence was written to separate the American colonies from Britain, but there were many underlying goals. It was written to state the grievances that the colonists held against the British, particularly the king. The colonists wanted a better economy, a new republican government, but perhaps most of all, they simply wanted their misery to end. This is what they set out to explain in the document. John Adams described it as â€Å"a Declaration setting forth the causes which have impelled us to this mighty revolution, and the reasons which will justify it in the sight of God and man† (Friedenwald 182). The forceful wording used in the introduction of the document was used for a reason. Jefferson writes, â€Å"When in the course of h... ... clear that government is subject to the people that it governs. The British realized that they could not write a document that would meet the demands of the colonists (Thomas 334). It was time for the colonists to write their own document. This document, the Declaration of Independence, was not only a stand against Britain; it was a stand for freedom. Works Cited Friedenwald, Herbert. The Declaration of Independence: An Interpretation and an Analysis. New York: Da Capo Press, 1974. Pleasants, Samuel A., III. The Declaration of Independence. Columbus, Ohio: Charles E. Merrill Books, 1996. Thomas, Peter D. G. Tea Party of Independence: The Third Phase of the American Revolution 1773-1776. Oxford: Clarendon Press, 1991. Wills, Garry. Inventing America: Jefferson's Declaration of Independence. Garden City, New York: Doubleday and Co., 1978.

Induction Theory Essay

Karl popper made his contribution on the induction theory in Vienna during the period of Logical Positivism despite the fact that he was not a Positivist. Before Popper’s contribution, Hume, another philosopher had already critised the theory of induction saying that the theory could not provide rational support for their conclusion (Karl, Raimund P. , 2002). His argument was based on assumption that induction assumes unobserved events which follow the pattern of observed events and ultimately it could not be logically justified whether it was deductible or in-deductible(Nelson, 1992). Hume justified that the theory of induction does not hold since it’s not logically true (Marc, 2000). Later Karl Popper supported Hume’s opinion on induction theory by fact that it could not give amicable solution but disagreed with Hume’s suggestion that science yield no knowledge of the nature of the world. On Popper’s side, he strongly felt that induction theory can be replaced by the principle of conjecture and refutation. On the experimentation of conjecture, it’s not possible to give positive inductive reasons for thinking that they are true while we can give justification of thinking that they are false. To experiment this scenario we take Poppers deductive method of conjecture and refutation principle together with induction principle to test scientific hypothesis. We can determine the expected results if the hypothesis is true, we can say the hypothesis is inductively confirmed if our observation agrees with our expectation while using induction theory. Such criteria of reasoning is not deductively correct, hence as an inductive argument, it faces the problem of induction. It therefore provides a convectional justification that ‘H’ is true. And, given this and the truth of the first premise, ‘0’ would follow. But ‘0’contradicts ‘not 0’which is asserted by second premise. From the hypothesis we can conclude that its not possible for premises to be true and conclusion be false. Popper’s method of conjecture and refutation provide us with the global knowledge to avoid the problem of induction. Karl Popper also asserted that there is no rational method that can be used to evaluate scientist’s justification about the hypothesis, further, there is no sufficient and appropriate evidence that can inductively confirm the hypothesis, that it can give us a positive reason to think that our hypothesis are true. Popper Karl contributed too in improving the meaning theory by providing an alternative solution to positivist verification which sorted out the demarcation issues (Nelson, 1992). Before the invention of Positivist verification there was a major problem in differeciating legitimate scientific inquiry from aspects such as religion and pseudo science. His methodology of conjecture and refutation still provides another basis for distinguishing ‘science’ from ‘non science’ since it enables us to take a hypothesis to be scientifically investigated if and only it’s falsifiable (Karl, Raimund P. 2002). For a hypothesis to be false we only highlight any likelihood observable conditions under which one can judge to ascertain to be false. To justify that it is false that all crows are black, we must state some realistic observable situations. By so doing we can categorically be certain that it is surely false, in case we observed a white crow. So, the assertion that all crows are black can be scientifically investigated. Also for a claim that opium makes sleep since it has normative virtue. This is a pseudo-scientific explanation since it’s not possible to state any observation for us to ascertain it is false. It will not be realistic and permissible to assume for instance, that the total population in Texas is 50 people (in millions) while in actual sense its 45 million people. The presumption would only be having some degree of truth which could be realistically correct to around 0. 9 percentage of the total population which can be inherited with questionable justice. If for instance to say that Jack is ‘borderline tall’ so that ‘Jack is tall’ is assigned the value 0. , then there could be a necessarily falsehood that ‘Jack is tall but not very tall’ to get a value of 0. 5. The most definite disadvantage for relying on such logistics is that they do not dispense with any sharp transition for they only accommodate very gradual heap to non heap at the very expense of exposing a sharp transition from heap to borderline, and from bounder line to non-heap (Catherine, 1997). This can be illustrated by the problem of higher-order vagueness as below   Its shows from the above scenario that we avoid assigning more precise numerical figures as degree of truth since such assignment will not have any substance either (Karl, Raimund P. , 2002). This is because true statements ought to be somehow differeciated from true statements or to treat them as neither true nor false, and categorize them as those which could become true or false (Marc, 2000). Goodman was for the idea that no answers which neither nor justifies limitations of induction. This is because we can satisfactorily distinguish between deductive and in-deductive. This is what made Goodman make tremendous efforts towards formulating canons off inductive interference which had to emphasize on ‘Emerald1 is green and Emerald 2 is green’. Goodman’s new riddle approach on induction indicates that this is a false step since not all instances are confirmed by their instances. This pioneered the invention of the predicate ‘grue’which is defined as; an object is grue only and if only the object is (1) green, and has been observed before now,or (2),blue, and has been observed before. Such definition gives a clear definition by the condition on when the word ‘grue ‘applies to an object, nevertheless it creates a problem when used inductive argument. If experiment 2000 green emeralds it provides sufficient evidence of believing that both the next emerald to be experimented will definite be green after observation, and that it will be blue, but this is absurd, to this assumption will worsen the scenario because inductive theory has weakness with the word grue and possibly with inductive arguments involving green Grue, if in the first instance presumed to be illegitimate for it makes reference to a particular time and it’s defined by the outcome color of an observation if observed at the moment. This makes it appear to be artificial while in actual sense it natural which makes its use an illegitimate inductive arguments. By defining grue in of two more other predicates that is green and blue which are not very simple and elaborative makes it unusual. Goodman has also highlighted that differences between properties of being grue and green which is dependent for them to be restricted to properties. In analyzing evaluation techniques in Goodman‘s New Riddle of induction he ascertained that the bold techniques are most likely to attain the goal of reliably arriving at the most right answer, while the most skeptical technique does not at all mean that in skeptic there is violation of canon of rationality or may be false to recognize nature uniformity. The theoretic learning analysis wholly concedes to be skeptic regardless the many ravens observed in the past, the next one could be white(Catherine, 1997). The rationality of this is that if all observed ravens are generally black, the skeptic doesn’t answer the question that all ravens will be black. In generalization of emeralds where green and blue colors were used Nelson puzzled about new riddle induction by performing the following experiment: supposing that all the examined emeralds before a particular time y are green, our evidence statements indicates that emerald n is green and so on†¦Ã¢â‚¬ ¦examining another spices which is less familiar than green it is the predicate ‘blue’ and this could mean that it applies to all items which were examined before y just incase they were green but to other things just incase they are blue. In such scenario the challenge is to we should conjecture that all emeralds are green rather than that all emeralds are grue when we obtain a sample of green emeralds examined before. We can still analyze induction theory in making projections, for instance a natural projection rule which conjectures that all emeralds are green as long as only green emeralds are found, and grue, some rule which keeps projecting the next grue predicate consistency with available evidence (Peter, 2003). The theory of meaning from philosophers’ analysis has been difficult to come up with a very clear definition of meaning theory this has been generally because meaning can only be specified by its wording and syntax. This is because only words or marks put on a paper can generate a meaning. Sentence is a composition of prepositions which indicate satisfactory conditions to make each sentence correct. Aspects such as beliefs, hopes and intention which explain speaker’s nervous system are found in the context of language.

Water Assisted Injection Moulding: a Study on the Influence of Melt and Process Parameters on the Residual Wall Thickness and the Occurrence of Part Defects for Pa6.

KATHOLIEKE HOGESCHOOL LIMBURG Departement Industriele Wetenschappen en Technologie Water Assisted Injection Moulding: A Study on the Influence of Melt and Process Parameters on the Residual Wall Thickness and the Occurrence of Part Defects for PA6. Gielen Bjorn, Heynickx Lien, Van den Brink Dominique, Vandersteegen Jochen Water Assisted Injection Moulding: A Study on the Influence of Melt and Process Parameters on the Residual Wall Thickness and the Occurrence of Part Defects for PA6. Gielen Bjorn, Heynickx Lien, Van den Brink Dominique, Vandersteegen Jochen Received 7 March 2011 Abstract Although water assisted injection moulding is a relatively new and advanced technique to produce hollow parts, several problems which reduce the product quality can occur. Namely, water inclusions in the wall, severe fingering and double wall defects reduce the product part stiffness. This study investigated the effect of the process parameters water volume flow rate, water injection delay time and melt temperature on the part defects to obtain a better understanding of the formation of these part defects. The effect on the residual wall thickness and the weight of the products was also investigated. Three materials were used: two polyamides and one polypropylene as a reference. The experiments were carried out on an injection moulding machine equipped with a water-injection unit to produce hollow handles. The parts were weighed before and after drying, their wall thickness was measured and their percentage of defects was calculated in order to determine the influence of the processing parameters. IR images and pressure profiles ware also used to investigate possible detection methods for part defects. It was found that all the investigated parameters have a significant influence on the residual wall thickness and part defects. Their ‘ideal’ settings depend on the material and the desired properties since small wall thicknesses and few part defects do not always correspond. IR images can give an indication for the presence of defects, but the internal structure of the surface can not be examined using this technique. Key words: water assisted injection moulding, polyamide, processing parameters, residual wall thickness, fingering, double wall 1. 1. Introduction The development of the water assisted injection moulding (WAIM) technique has led to a breakthrough in the manufacturing of hollow or partly hollow plastic parts, which is not possible with the conventional injection moulding process [1] [2]. These hollow parts are characterised by the lighter weight of the products, relatively lower resin costs per part and less shrinkage and warpage compared to conventional moulded products [3]. Several techniques are available for the production of hollow parts. Two of the most important techniques for hollow parts are gas assisted injection moulding (GAIM) and water assisted injection moulding (WAIM). The principle of water assisted injection moulding is basically similar to gas assisted injection moulding, but the use of water has some interesting advantages over gas assisted injection moulding such as a shorter cycle time and an average smaller residual wall thickness of the products. This is due to the fact that the thermal conductivity and the heat capacity of water are respectively 40 and 4 times greater than those of gas [1], providing a better cooling of the part and therefore a faster production. Water assisted injection moulding is better to mould larger parts with a smaller residual wall thickness. Another advantage of water assisted injection moulding is the absence of the foaming phenomenon in the internal surface which can occur by using gas assisted injection moulding , since water does not dissolve or diffuse in the polymer melt during injection moulding. Disadvantages of water assisted injection moulding are part defects such as fingering and double wall arising in the internal surface. Also, the process is more complex so experience with conventional injection moulding is no guarantee for understanding water assisted injection moulding. The control f the process is much more critical, the design of the mould is more complicated and requires more knowledge of the dynamic interaction between the polymer and the filling water [4]. In addition, new water related processing parameters (water pressure, water injection delay time, water temperature, †¦ ) are involved and require proper adjustment [5]. The technology can be used to mould a large variety of polymers, includi ng glass fibre reinforced composites. Liu [6] reported the successful moulding of PP, PE, ABS and glass fibre filled polyamide 6 (PA6) composites with water assisted injection moulding. According to our investigation, few researchers have described the moulding of pure polyamide 6 with the water assisted injection moulding technique. By understanding the water assisted injection moulding process for this polymer, one is able to optimize the production and improve the product quality of PA6 parts. The water assisted injection moulding process can be applied in four variations [1] [6], which differ by the amount of injected polymer and introduction and evacuation of the water. In the short shot moulding process the cavity is first partially filled with polymer and in the next sequence, highly pressurised water is injected into the polymer core. The pressure is maintained during the cooling sequence to minimize the shrinkage and to further cool down the part. After cooling, the water is evacuated and the part is ejected. This technique is useful for thick parts, but the important limitation is the switchover mark on the surface [7]. This limitation can be eliminated by using the full shot moulding process in which the cavity is first completely filled with polymer. Next, the injection of water pushes the melt into a cavity positioned outside the cavity of the product. This overspill cavity arises by pulling back a core to enlarge the mould cavity for the overspill polymer which has to be removed from the product afterwards. Full shot moulding makes it possible to mould parts with a more uniform residual wall thickness through the end of the part in comparison to short shot moulded parts. Michaeli et al. [6] stated that the melt-push-back process is also capable to produce parts with a more uniform residual wall thickness distribution. In this process the water is injected in the reversed direction of the polymer injection and pushes the excess of melt back into the plasticizing unit. Finally, the core-pulling process uses a series of steel cores that are pulled back during water injection to increase the cavity volume and the product volume. This method produces parts with more uniform internal profiles in comparison to the former mentioned techniques. The investigated polymer, polyamide 6, is a semi-crystalline material that is classified as an engineering plastic. Beneficial properties of polyamide 6 over a wide range of temperatures and humidity are its high strength, high stiffness and toughness, good wear and abrasion resistance, low coefficient of friction and good chemical and electrical resistance [8], [9], [10], [11]. Further modification can be obtained by adding additives like fillers and plasticizers. Fillers achieve a better strength and stiffness, plasticizers cause higher toughness [12], [13]. Modification of the molecular weight has also a distinguishable influence on the polymer properties. The main drawback of polyamide 6 is the high moisture absorption affecting the rheological properties and deteriorating the processability. High moisture absorption causes part defects and results in a bad internal surface quality reducing the stiffness of the end product [14], [15], [16]. The absorbed water in the polymer has two important roles. Firstly, the water molecules act as plasticizers reducing the hydrogen bond interactions between the polyamide chains. Secondly, due to the hygroscopic nature of polyamide 6, the absorbed water influences the condensation reaction equilibrium depending on the initial moisture content [17], [18]. If the moisture content is less than prescribed thermodynamically, the reaction proceeds towards further condensation and an increase in molecular weight, increasing the viscosity exponentially. If the moisture content is higher than determined by the equilibrium, a hydrolysis reaction occurs. This causes a decrease in viscosity as well as degradation of the polymer. To properly process polyamide 6, the pellets are preferably dried to small moisture levels. Possible part defects that may occur in water assisted injection moulding are fingering and double wall. Liu and Lin [19], [20] investigated the problem of fingering in water assisted injection moulded composites. The fingering phenomenon comprises the non-uniformly penetration of water bubbles or steam into the polymer wall outside the designed water channels causing the formation of finger-shaped branches and small cavities in the polymer wall, which lead to a bad internal surface quality and a reduced part stiffness of the end product. Fingering depends on the dimension of the part: thick parts usually exhibit less fingering pattern than thin parts. Three factors might affect the formation of fingering. The first one is shrinkage of the polymer during cooling. During post-filling, the polymer undergoes volumetric shrinkage allowing water to penetrate into the parts. The more the polymer shrinks, the more water will penetrate into the part and causes fingering. However, this statement is in contradiction with the statement that thick parts exhibit less fingering, so research is necessary to investigate which conclusion is relevant for PA6. Shrinkage also depends on the crystallinity of the polymer. PA6 is a crystalline polymer and thus expected to show more shrinkage than an amorphous polymer. Also, water injection moulded parts show more fingering than gas injection moulded parts since water has a higher cooling capacity than gas and has a higher cooling rate of the polymer. This leads to a greater non-uniform temperature distribution in the polymer material which worsens the uniformity of water penetration inside the parts, resulting in fingering [20]. This is equal to the statement that more shrinkage leads to more fingering. The second factor is the viscosity of the polymer melt. During water injection, water follows the path with the least resistance. While the water enters into the mould cavity, it cools the polymer melt and increases the viscosity. It then becomes more difficult for the water to penetrate into the core of the parts. The third factor is the flow resistance in the channel and in the polymer. The higher the flow resistance in the channel and the lower the flow resistance in the polymer, the more water fingering will be induced. The researchers [19] concluded that water fingering worsens when a combination of a higher water pressure, a smaller melt short shot size and a shorter water injection delay time is used. Other parameters which need to be paid attention to are the temperatures of the melt, the mould and the water. Increasing these parameters decreases the cooling rate and the viscosity and results in more fingering because it is easier for water to penetrate in the part. Another possible part defect in water assisted injection moulding is double wall [22]. Double wall is the appearance of a second polymer wall inside the hollow product which deforms the wall significantly. During the water hold time water inclusions develop in the wall. The double wall is caused by the pressure drop after the water hold time. The water in the inclusions becomes steam and expands the internal material surface causing a second wall in the polymer. Two important parameters are responsible for the forming of double wall. The first parameter is the water hold time which should be minimized in order to eliminate double wall. Increasing the water hold time compensates the shrinkage in the wall but enlarge the water inclusions in the wall worsening the double wall. The second parameter is the volume flow rate. Increasing the volume flow rate causes more double wall because more water penetrates in the polymer forming water inclusions which expand into double walls after the water hold time. There is not much known about the phenomenon of double wall. A lot of investigators do not even make a difference between fingering and double wall and characterize it as the same part defect. Hollow parts are mainly characterized by their residual wall thickness that should be minimized in order to obtain a good product quality with minimal defects. A decline in wall thickness is mainly obtained by choosing water assisted injection moulding instead of gas assisted injection moulding [4]. However, Michaeli et al. [22] concluded that in some cases gas assisted injection moulding yields parts with a smaller residual wall thickness. Several process settings can be applied for water assisted injection moulding, each having an influence on the residual wall thickness. Huang and Deng [23] concluded that besides the short shot size there are two other main parameters affecting the residual wall thickness in polypropylene samples. The first parameter is the melt temperature. Increasing the melt temperature leads to reduction of the solidified layer thickness and thus to a decrease in wall thickness. The second parameter is the water injection delay time. When increasing the water injection delay time, the residual wall thickness exhibits an increment because the solidified layer of the melt becomes thicker. Liu and Wu [24] researched the effect of the injection pin on the residual wall thickness distribution. In their research they concluded that a pin consisting of a sintered porous surface can mould large parts with a more uniform residual wall thickness distribution. Application of this high flow rate pin could significantly improve the product quality in terms of smaller wall thickness. The non-uniformity of the residual wall thickness distribution usually occurring in curved product sections, was found to be less in water assisted injection moulded parts than in gas assisted injection moulded parts. Fluids try to follow the path with the least resistance; this is the shortest path. However, water has a higher mass inertion than gas and therefore gives a better concentricity of the residual wall thickness over a cross-section. The uniformity of the residual wall thickness could be improved by adopting different mould temperatures [25]. In order to mould PA6 parts with high product quality using WAIM, one has to apply the optimal settings to reduce the part defects (fingering and double wall) and decline the residual wall thickness. The water injection delay time influences fingering and the residual wall thickness. A shorter water injection delay time causes a smaller residual wall thickness but results in more fingering [19] [23]. The water volume flow rate is an important parameter on fingering, double wall and the residual wall thickness. A higher water volume flow rate gives a smaller residual wall thickness but more fingering and double wall [21]. The melt temperature has an influence on fingering and the residual wall thickness. Increasing the melt temperature leads to a smaller residual wall thickness but to more fingering [19] [20] [23]. Further experiments in this research focuses on the influence of the water injection delay time, the water volume flow rate and the melt temperature on the residual wall thickness and the occurrence of part defects for PA6, using a design of experiments. 2. Experimental procedure 2. 1 Materials To investigate the residual wall thickness and part defects like water inclusions, fingering and double wall of water assisted injection moulded products, two polyamides (PA F223-D and PA F130-E1 from DSM) and a polypropylene (PP 400-GA05 from Ineos) were used. The melting and crystallization temperature of the materials were measured with differential scanning calorimetry (TA Instruments 2920 CE). The viscosity was measured with a capillary rheometer (CEAST Smart Rheo 2000 twin bore). The complex viscosity, storage and loss modulus were measured with a parallel plates rheometer (AERES strain controlled rheometer). The measurements show that the zero-shear viscosity of the polypropylene is higher than those of the polyamides. PA F223-D has a higher zero-shear viscosity than PA F130-E1. This indicates that the molecular weight is higher for polypropylene than for PA F223-D and that PA F130-E1 has the lowest molecular weight. The decrease in viscosity at higher shear rates occurs at lower frequencies for polypropylene in comparison with the polyamides. This indicates a higher molecular weight distribution for polypropylene than polyamide. PA F223-D has a higher molecular weight distribution than PA F130-E1. . 2 Moulded parts The part that is moulded for this experiment is displayed in figure 1. It contains four curved sections varying in radius of curvature. The polymer and water enter the cavity at the bottom side. Water enters when a movable injector is pushed forward and a core at the end of the part is pulled allowing the polymer to be removed out of the inner core of the part. Figure 1: moul ded part containing four curved sections 2. 3 Equipment The injection moulding was executed with an Engel 80-ton injection moulding machine ES 330H/80V/80HL-2F. The dimensions of the machine are 4,80 m x 2,22m x 2m. The single screw diameter is 50 mm and the plastification unit can operate with a maximum injection rate of 152 cm? /s. A volume flow rate controlled water injection unit brings the water into the mould. It can operate with a maximum water volume flow rate of 30 l/min, delivered by a maximum pressure of 200 bar. During the tests a maximum pressure of 160 bar was applied. Three pressure sensors type Priamus are localized in the mould. An IR-camera type FLIR is used to observe the temperature distribution over the produced handles after moulding. The IR-images were used to compare with the internal section to discover the cause of part defects, because water in the product gives lower temperatures on the IR-image. The dried hollow polymer handles are sawed in lengthwise direction with a band saw. The band saw is type Metabo bas 260 swift. After sawing the hollow polymer handles, the internal section were scanned with a scanner type Cannon FG17500. A metric software 8. 01 plus was applied to analyze the surface quality of the polymer. With the aid of the software, the surface area of the wall and the part defects can be determined. . 4 Method DOE procedure The experiment investigated four processing parameters that were selected after a preliminary literature study, assuming these will have a significant influence on the residual wall thickness and part defects. These parameters are the water volume flow rate, water injection delay time and melt temperature. Using the design of experiments approach, each parameter was measured on a low and high setting; making this a 23 experiment. In addition three centre points were measured bringing the total number of experiments to 11 for each material. Response functions were constructed for residual wall thickness, weight and defects. The significance of each parameter was checked by comparing its effect to the deviation of the centre points, neglecting the parameter if its effect is smaller than the centre point deviation. Experimental procedure After steady state was reached, five shots were produced for each setting of water volume flow rate, water injection delay time, melt temperature. For each last shot of an experiment, a print screen of the pressure evolution and an IR-image was taken. During the process the following parameters were measured: * real injection time; * absolute shot volume; * real cushion; * flow number. After moulding, the parts were dried with compressed air to remove water of the inner- and outer surface of the product. Then the injection side of the product was removed and both halves were weighed. The sawed injection product was controlled on the presence of defects giving a first indication of the quality of the product. Afterwards the handle was dried in a furnace for 44 hours on 90  °C. After drying, the handles were weighed again obtaining the weight of the water inclusions in the product wall. Three representative handles were sawed in lengthwise direction and the breams were removed. The handles were scanned to determine the residual wall thickness and the percentages of defects like water inclusions, fingering and double wall. Table 1: Processing variables and settings used for the experiments | A| B| C| Process parameters| Water volume flow rate (l/min)| Water injection delay time (s)| Melt temperature ( °C)| -1| 10| 1,5| 240| 0| 20| 5| 260| 1| 30| 8,5| 280| A| B| C| Experiment| Water volume flow rate (l/min)| Water injection delay time (s)| Melt temperature ( °C)| 1| 20| 5| 260| 2| 10| 1,5| 240| 3| 30| 8,5| 240| 4| 30| 1,5| 240| 5| 10| 8,5| 240| 6| 20| 5| 260| 7| 30| 8,5| 280| 8| 10| 1,5| 280| 9| 10| 8,5| 280| 10| 30| 1,5| 280| 11| 20| 5| 260| Table 2:Experiment schedule for parameter settings The part defects are calculated as follows: The parameters whic h have an influence on the product quality are the water volume flow rate, the water injection delay time and the melt temperature. The tested parameter settings are presented in table 1. A code using -1 for low, 0 for center point and 1 for high setting is applied. The combination of parameter settings (Table 2) are determined using design of experiments. Using the design of experiments method makes is possible to obtain a better understanding of the formation of the defects and the influence of the processing parameters. Eventually a moulding window will e determined in which the defects are minimized. 2 Results and discussion 3. 1 Effect of water volume flow rate Figure 2 shows the effect of the water volume flow rate on the residual wall thickness and the product defects. Following paragraphs discuss these diagrams. Influence on the residual wall thickness and product weight Considering the residual wall thickness, polypropylene has a smaller residual wall thickness than the residual wall thickness of polyamide for all experiments. Polypropylene has a higher molecular mass, causing a wider water flow front. The higher molecular weight distribution (MWD) of PP causes a block velocity profile of the water resulting in a higher velocity on the polymer- water interface. The higher velocity causes a higher shearing and consequently a lower viscosity, resulting in a higher removal. This results both in a smaller residual wall thickness and a lower part weight. The density of polypropylene is lower compared to compared to the density of polyamide, which is also an explanation for the lower weight of product. Regarding the product weight and the residual wall thickness, the two polyamides do not differ much and correspond to each other. This is probably due to the small difference in molecular mass and molecular weight distribution. Figure 2: Effects of water volume flow rate on water inclusions, residual wall thickness, fingering and double wall The residual wall thickness of polyamide seems not to be significantly affected by the water volume flow rate. Polypropylene however, tends to increase in residual wall thickness by application of a lower water volume flow rate. These results correspond to the suggestion that a higher water volume flow rate gives a smaller residual wall thickness, as was found in preliminary literature study. In general a material with a high MWD, like PP, will be more influenced by the flow rate than other materials like polyamides. Influence on water inclusions In general the water inclusions tend to decline when the water flow rate increases. A higher flow rate provides more shearing, giving a lower viscosity. The water can easily remove the internal polymer and does not penetrate into the walls of the polymer. PP completely corresponds to this theory, but the polyamides show an irregularity during high flow rates. this can be explained by the strong variations in injection time and a chance in the water flow profile to a profile called recirculation flow. It pushes the water into the walls causing an increase in water inclusions. The strong variations that occur with PP are probably caused by its high MWD. This property also played an important role regarding the RWT. Influence on fingering Fingering is probably caused by differential shrinkage, making a material with a high degree of crystallization like polypropylene vulnerable to this defect. The defect diminishes at high flow rates where the wall thickness is smaller, making it more difficult for polypropylene to shrink and for fingering to occur. PA F130-E1 exhibits a low variation in fingering in comparison to the other materials. This material is not in its area of shear tinning when working with low flow rates, resulting in a constant viscosity and residual wall thickness. Because of this low variation in RWT and corresponding shrinkage with changing flow rate the effect of the flow rate will be very small. In general materials with a high MWD and MM like PP show more fingering than materials with low MWD and MM like PA F130E1. PA F223D will take a intermediate position taking into account that its centre point is not completely representative. This trend for fingering is visible for all parameters. Influence on double wall The influence of the flow rate shows an overall optimum profile. Low and high flow rates cause more double wall than an intermediate setting. A first theory relates this effect to the pressure inside the part. Low flow rates exert low pressure on the polymer melt and the polymer will not form a rigid layer, making it possible for the water to penetrate into the polymer walls. High flow rates cause high pressures inside the part forcing the water into the walls. The second theory is based on the tendency of water to follow the ath of least resistance and can only explain the effect with low flow rates. The low rate will cause almost no shear stress inside the polymer so it will not reach the shear tinning area. The polymer will not easily be pushed back by the water and the water will penetrate the walls where the resistance is much lower. The effect of the water volume flow rate on double wall is the same as for water inclusions, which is explained by the rel ation between water inclusions and double wall. Water inclusions can grow during the water hold time, collapsing into double walls in the product after pressure removal. The higher double wall defects for PAF130-E1 in comparison to PA F223-D are probably caused by the difference in molecular mass. PA F130-E1 has a lower molecular mass and thus a less viscous melt resulting in a more easily penetrable material. Another noticeable result is that of the investigated materials, PA F223-D shows high part defects but relatively the smallest double wall defects. PP, the material with the highest MM shows more double wall at high flow rates for which no explanation can be found. 3. 2 Effect of the water injection delay time Figure 3 shows the effect of the water injection delay time on the residual wall thickness and the product defects. Following paragraphs discuss these diagrams. Influence on the residual wall thickness and product weight A shorter water injection delay time causes a decline in the residual wall thickness and weight of product for polyamide and polypropylene, as was predicted by literature. When the water injection delay time is short, the polymer is still hot and has a low viscosity, giving the water the opportunity to hollow out the polymer more. A higher water injection delay time causes a higher residual wall thickness and weight of product because the melt viscosity increases. The residual wall thickness is higher for polyamide than for polypropylene, for the same reasons as discussed under the previous paragraph. Influence on water inclusions An increase in delay time is accompanied by an increase in viscosity that makes it more difficult for the water to penetrate into the walls. However, if the viscosity is too high, the water can also be forced into the walls, which explains the slight increase in water inclusions for PP 400-GA05 and PA F130-E1. Figure 3: Effects of the water injection delay time on water inclusions, residual wall thickness, fingering and double wall The strong decrease in water inclusions that occurs with polypropylene is caused by the high heat capacity of this material making it cool down faster than the polyamides and increasing its viscosity faster. PA F130-E1 shows less defects in comparison with PA F223-D, probably caused by its strong temperature related viscosity. During the delay time the viscosity strongly increases, making it more difficult for the water to penetrate. Influence on fingering Increasing the delay time increases the residual wall thickness and should result in a higher chance of fingering. In general this trend can be observed from the diagrams. More fingering occurs within PP 400 GA05 caused by its higher degree of crystallization. Furthermore, this polymer is processed at much higher temperatures than its melting point, leading to further shrinkage and corresponding fingering. The presence of defects during processing with long delay times is caused by a greater residual wall thickness, which leads to more differential shrinkage. Processing with short delay times increases the presence even further, but no plausible statement can explain this. Therefore further research will be necessary. The results for the centre point of PA F223-D are probably not representative, since it is based on a single experiment of three shots. Influence on double wall The water injection delay time shows an overall optimum profile, which can be related to the shift of the rigidity in time, caused by the temperature drop over time. Production with a short delay time will push water inside the low viscosity polymer which makes it easy for the water to penetrate. Increasing the delay time also increases the viscosity and thus the rigidity of the polymer making it harder to penetrate the walls. However, if the viscosity is too high, the water will also be forced into the walls. PA F130-E1 shows more double wall because its viscosity is highly temperature related. Longer delay times will lead to larger temperature drops and a corresponding increase in viscosity. 3. 3 Effect of the melt temperature Figure 4 shows the effect of the melt temperature on the residual wall thickness and the product defects. Following paragraphs discuss these diagrams. Influence on the residual wall thickness and weight of product Considering the residual wall thickness, polypropylene has a lower residual wall thickness and weight of product compared with polyamide for all experiments. This might be due to the higher molecular weight and the higher molecular weight distribution of polypropylene. The higher molecular weight distribution shows a square blocked velocity profile causing a higher velocity on the wall and a higher shearing. This results in a lower viscosity and therefore more removal of the polymer decreasing the residual wall thickness and weight of product. PA F130-E1 and PA F223-D are quite similar and do not differ much in residual wall thickness and weight of product. Increasing the melt temperature leads to a smaller residual wall thickness as was suggested by literature, because a higher melt temperature makes the polymer less viscous so more polymer can be removed by the water. The residual wall thickness of PP decreases from 240 °C to 260 °C but increases to 280 °C. The increase of the melt temperature is difficult to explain and is possible a unreliable point. In fact, also for polypropylene a decreasing tendency is remarkable. Influence on water inclusions There is a trend towards higher water inclusions when a higher melt temperature is applied. This parameter thus shows the opposite effect of the delay time. PA F130-E1 differs from the other materials, probably due to the strong variations in injection time during production. Furthermore this polymer shows a lot of internal heating (viscous heating) when Figure 4: Effects of the melt temperature time on water inclusions, residual wall thickness, fingering and double wall high pressure is exerted, leading to a drop in viscosity. This effect usually appears in combination with low melt temperatures where the polymer has a lot of pressure to bear. So low temperatures will lead to viscous heating and therefore to high intern temperatures. The water can then easily enter the walls of the polymer due to the lower vicosity. Influence on fingering When processing the material at low temperatures, the material will have to shrink less and thus less fingering will occur. This trend is clearly visible for the polyamides, taken into account that the centre point of PA F223-D is not representative. In fact, the effects should show an opposite effect from the delay time, but this is not clearly noticeable. Further research will be necessary to explain these irregularities. Influence on double wall A higher melt temperature causes an overall increase in double wall defects for all three materials. This effect is related to the viscosity of the polymer which varies with temperature. High temperatures will lead to a decrease in viscosity making the polymer more penetrable for water. Another theory is based on the water flow profile inside the polymer. Higher temperatures usually correspond to smaller residual wall thicknesses changing the flow profile into a recirculation flow where water will be pulled into the walls. 3. 4 Comparison results of response functions and graphical tendencies Table 3 gives an overview of the best parameter settings to reduce each part defect and the total defects for each material, comparing the results of a response function (before /) and the graphics in figure 1/2/3 (after /). The response functions were constructed using the design of experiments method. Regarding the defects, only one response function was made which ncludes both fingering and double wall. Ideal settings according to response functions Using the response functions several conclusions can be made for the ideal settings of the parameters. A high water injection delay time creates less water inclusions in both polyamides. In addition, the polyamides show the same optimal settings of all parameters for the residual wall thickness. A low water volume flow rate is beneficial for the reduction of the residual wall thickness, fingering and double wall. Other settings conflict to give minimal part defects in polyamide. In general, PA F223-D has minimal part defects for a low water volume flow rate, a high water injection delay time, and a low melt temperature. PA F130-E1 requires a low water volume flow rate as well, but a low water injection delay time and a high melt temperature. The optimal settings for the minimal percentage water inclusions, fingering and double wall are highly contradictory for polyamide and polypropylene. PP 400-GA05 requires a high water volume flow rate for a smaller residual wall thickness but the other parameters have the same optimal settings for the residual wall thickness as polyamide 6. The water volume flow rate and the water injection delay time do not influence fingering and double wall significantly, so no conclusions can be made for these settings to obtain minimal fingering and double wall. If also the water inclusions and the residual wall thickness are taken into account, PP400-GA05 shows minimal part defects for a high water volume flow rate, a low water injection delay time and a low melt temperature. There can be concluded that for all three materials the best parameter settings for residual wall thickness, fingering and double wall are not the same. Since other effects may probably have an influence on the materials, further investigation will be necessary. Ideal settings according to previous diagrams The following best parameter setting are based on the previous graphics. Regarding the residual wall thickness, the best parameters for PP and PA F130D are an intermediate water flow rate, a low water injection delay time and a high melt temperature. For PA 223D, a low water flow rate is required and the other parameters are the same. For fingering, a high water volume rate, an intermediate water injection delay time and melt temperature give the best results for PP. PA F223D gives the best results for a low water volume flow rate and water injection delay time and an intermediate melt temperature. PA F130E1 in contrary, the best parameters setting are a high water volume flow rate and a low water injection delay time and melt temperature. The parameters setting are different for the three materials and show a lot of irregularities. Considering double wall, the best parameter settings are a low water flow rate, water injection delay time and melt temperature. For both polyamides the best parameter setting are equal, an intermediate water flow rate, delay time and melt temperature. For the water inclusions, the best results were observed for a high water volume rate and an intermediate water delay time and melt temperature. PA F223D shows less water inclusions when an intermediate flow rate, a low delay time and in intermediate melt temperature is used. PA F130E1 in contrary gives the best results for a intermediate flow rate and delay time and a low melt temperature. Ideal settings for PA F223-D| | Optimal setting| Response factor| Target figure| Water volume flow rate| Water injection delay time| Melt temperature| Water inclusions| Low| High/High| High/High| Low/Low| Residual wall thickness| Low| Low/High| Low/Low| High/High| Fingering and double wall| Low| Low/High| High/Low| Low/Low| Total| | Low/High| High/Low| Low/Low| Table 3: Overview of ideal settings for the materials for each part defect Ideal settings for PA F130-E1| | Optimal setting| Response factor| Target figure| Water volume flow rate| Water injection delay time| Melt temperature| Water inclusions| Low| Low/High| High/High| High/Low| Residual wall thickness| Low| Low/High| Low/Low| High/High| Fingering and double wall| Low| Low/High| Low/Low| Low/Low| Total| | Low/High| Low/Low| High/Low| Ideal settings for PP 400-GA05| | Optimal setting| Response factor| Target figure| Water volume flow rate| Water injection delay time| Melt temperature| Water inclusions| Low| High/High| Low/High| High/Low| Residual wall thickness| Low| High/High| Low/Low| Low/High| Fingering and double wall| Low| -/High| -/Low| Low/Low| Total| | High/High| Low/Low| Low/Low| Once again, here can be concluded that the best parameter settings for residual wall thickness, fingering and double wall are not the same. Since other effects may probably have an influence on the materials, further investigation is necessary. . 5 Detection of part defects 3. 5. 1 IR-images IR images were tested if they can be used to obtain an indication of the quality of the product. This could be an important tool during production as it can deliver information about the internal structure without damaging the part. It was found that a uniform heat distribution in the part usually corresponds to few defects in the walls. The polymer equally shrinks and cools, causing no stress in the walls which could lead to defects. Figure 5 shows the section and an infrared image of a hollow part from PP 400-GA05 without defects. The corresponding IR picture shows no significant Figure 6: Scan and IR image of PP 400-GA05 product with defects irregularities in the heat distribution. The areas where the part has a higher or lower Figure 5: Scan and IR image of PP 400-GA05 product without defects temperature than the bulk are caused by respectively larger and smaller residual wall thicknesses. Small defects like fingering can occur where colder areas are completely surrounded by larger hot material making it isolated cold regions. If the cold area is gradually spread throughout the part and is therefore no isolated region, fingering is often not present. The isolated colder regions are most likely filled with water which provides more efficient cooling than the rest of the part, resulting in uneven shrinkage and corresponding fingering cavities. Large defects like double wall are often present where a relative large cold area spreads throughout the complete section and is surrounded by hot material. These defects are also likely to occur in regions with higher temperature than the rest of the part. However, the latter can also correspond with a larger residual wall thickness and is thus not conclusive for the presence of double wall defects. Figure 6 shows a part with double wall defects and the corresponding infrared image where the isolated hot (white) and cold areas (yellow) are indicated. The texture of the internal surface can not be judged with an infrared image. PA F130-E1 tends to show a rougher surface in regions with a much lower temperature, but not all parts share this conclusion. Within the other materials a rough surface does not corresponds with lower temperature areas thus the infrared does not delivers clear information about this property. 3. 5. 2 Pressure and injection rate profiles The pressure profiles and the injection rate during the injection of the melt can be used to declare some of the defects shown in the different polymer samples. The injection rate was set on 45 mm/sec and the maximum feasible pressure of the WAIM equipment was 160 bar. For the polyamides, this maximum pressure was exceeded in some cases during filling of the mould. This caused a temporary reduction of the injection rate and possibly some of the part defects of polyamide. Polypropylene does not show this trend because it has a lower flow number than PA. Figure 7 shows an example of this phenomenon in PA F223-D. In general it can be concluded that when the temperature increases the measured pressure and the flow number decrease. This reduction in pressure can be explained by the fact that the viscosity of the material will be lower at a higher temperature, so the polymer can flow easier and less pressure has to be applied. However it is not guaranteed that an irregularity in the injection profile of the polymer results in problems during water injection. This experiment was to limited to make clear conclusions about this effect. Figure 7: Pressure and injection rate profile for PA F223-D (green=pressure, blue=injection rate) 4. Conclusions 4. 1 General This report has studied the influence of melt and processing parameters on the residual wall thickness and the occurrence of part defects of PA6 parts produced with water assisted injection moulding. The study examined two polyamides (PA F223D, PA F130E1) and polypropylene 400 GA05 that was used as a reference material. According to a design of experiments, the water volume flow rate, the water injection delay time and the melt temperature are the investigated processing parameters. The water volume flow rate settings are 10, 20 and 30 l/min, the injection delay time settings are 1,5s, 5s and 8,5s and the melt temperature settings are 240 °C, 260 °C and 280 °C. It was found that the residual wall thickness showed a large distribution for all three materials, even for shots from a single experiment and therefore an extra analysis was made on the weight of the products. The product weight can give an indication for the wall thickness as a low weight usually corresponds to small thicknesses. Based on this theory it was found that the water volume flow rate has little influence on the weight and wall thickness. A larger delay time increases the viscosity of the polymer and leads to higher weight and a larger wall thickness. The melt temperature has the opposite effect, decreasing the viscosity at higher temperatures and therefore decreasing the wall thickness and weight. PP has a lower weight comparing with the two polyamides. This can be explained that PP has a higher molecular weight and molecular weight distribution. A higher molecular weight gives a parabolic velocity profile and a higher molecular weight distribution shows a square blocked velocity profile causing a higher velocity located on the wall. The higher velocity causes a higher shearing giving a lower viscosity. This results in more removal of the polymer and the residual wall thickness decreases. In fact, a lower residual wall thickness exhibits a lower weight of product. The water inclusions for the three materials tend to decline when the water flow rate increases although PP shows some irregularities. The delay time has an overall optimum profile. Intermediate settings exhibit less inclusions in comparison to other settings. The melt temperature has the opposite effect of the delay time so more water inclusions occur when higher temperatures are applied. Other defects like fingering and double wall are also influenced by the investigated processing parameters. The water flow rate shows an optimum profile for double wall, so an intermediate setting will yield the best results. For fingering the three materials all act in a different way to the flow rate. An optimum profile also occurs for double wall when the delay time is investigated. In general, fingering increases when the delay time increases, but the materials show a lot of irregularities. An increase in melt temperature causes an overall increase of fingering and double wall. Comparing PA6 and PP, PP shows an overall smaller residual wall thickness than PA6, but on average the same percentage of part defects. This means that a reduction in residual wall thickness does not influence the product quality for part defects positively. When comparing the different polyamides 6, the investigated low viscosity polyamide 6 PA F223-D show less water inclusions and fingering but more double wall than the medium viscosity polyamide 6 PA F130-D. The best choice for a polyamide depends on the relative importance of the negative influence of each part defect on the product quality. This is discussed in detail in the next paragraph. To get an indication of the quality of the product IR images can be used. It was found that a uniform heat distribution corresponds to few defects and irregularities point to the presence of defects like fingering or double wall. The internal texture of the surface can not be examined with IR. This study concludes that the investigated parameters have a significant influence on the presence of part defects and on the residual wall thickness. However, there are still irregularities in the results of the fingering phenomenon that can not be explained yet with the current knowledge of the water assisted injection moulding process. Therefore further analysis will be necessary to examine this part defect. Further research can be done by expanding the design of experiments and by producing more shots for each experiment. Producing more than three shots of each experiment should give more corresponding results, because the standard deviation of three shots is usually high. 4. 2 Selection of the material for WAIM Three materials were used in this experiment namely PA F223D, PA F130E1 and PP as reference. The residual wall thickness, weight of product, water inclusions and part defects like fingering and double wall must be compared with each other to choose the best material. This by varying the selected parameters like water volume rate, water injection delay time and melt temperature. PP has in general the lowest weight of product and residual wall thickness for the three investigated parameters: water volume rate, water injection delay time and melt temperature. As a result of a smaller residual wall thickness, PP has the lowest weight of product. Considering the water inclusions a decreasing tendency is obtained when a higher water volume flow rate and water injection delay time is used. There is a trend toward higher water inclusions when higher melt temperature are applied. Regarding to fingering and double wall, an opposite effect is noticeable. Increasing the water volume rate and water injection delay time gives a decreasing fingering tendency but more double wall effects. For a higher melt temperature, an increase of fingering and double wall is observed. PA F130E1 and PA F223D are quiet similar to each other in weight of product and residual wall thickness. For the weight of product PA F130E1 and PA F223D correspond to each other and for the residual wall thickness they do not differ much for all three investigated parameters. Regarding the water inclusions, both polyamides decline when water the flow rate increases. The highest flow rate provides more shearing and therefore a lower viscosity resulting in more water inclusions. Increasing the water injection delay time leads to lower water inclusions because the viscosity increases which makes it more difficult for water to penetrate into the walls. When higher melt temperatures are applied, results in a trend towards higher water inclusions because of the lower viscosity. In general, PA F223D shows more water inclusions comparing with PA F130E1 for the water volume flow rate, water injection delay time and the melt temperature. Considering fingering and double wall, different results were observed for the two polyamides. In general it is remarkable that PA F223D shows more fingering then PA F130E1 while PA F130E1 gives more double wall then PA F223D and this for the three investigated parameters. For the water volume flow rate, the polyamides act in different ways towards fingering. Although, for double wall the flow rate shows an optimum for the polyamides so an intermediate setting gives the best results. When the water injection delay time increases there is also an increasing tendency of fingering observed but the materials show a lot of irregularities. Increasing the melt temperature gives an increase of fingering and double wall as well. In this investigation can be concluded that both polyamides have their advantages and disadvantages. A selection of the best polyamide depends on which effect is undesirable. The residual wall thickness are the same for the two polyamides. PA F223D shows more water inclusions and fingering for all investigated parameters. However, PA F223D shows less double wall and therefore the best results. PA F130E1 in contrary gives more double wall effects but less fingering and water inclusions. In fact, PA F223D is preferred when double wall must be reduced and PA F130E1 is preferred when fingering and water inclusions must be reduced. Further investigation is necessary on another type of polyamide which improves the product quality using WAIM. 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