Saturday, August 31, 2019
Faith of Children by Proxy Essay
In response to the query as to how an infant can be capable of making an act of faith, which is regarded as being necessary for baptism; Catholics refer to faith of infants born into Christian home, as guaranteed by faith of their parents and sponsors. The parents of such infants have the bounding duty to bring them up as Christians. When such children have grown in the faith their baptism is now given ââ¬Ëconfirmationââ¬â¢. In Mark 2: 1-5, an example of faith by proxy, sufficient for salvation of another is often cited by Catholics. ââ¬ËAnd after some days, He again entered into Capernaum. And it was heard that He was in the house. And so many gathered that there was no room left, not even at the door. And He spoke the word to them. And they came to Him, bringing a paralytic, who was being carried by four men. And when they were not able to present him to Him because of the crowd, they uncovered the roof where He was. And opening it, they lowered down the stretcher on which the paralytic was lying. Then, when Jesus had seen their faith, he said to the paralytic, ââ¬Å"Son, your sins are forgiven you. â⬠ââ¬â¢ {Mark 2:1-5} In this passage, the Lord Jesus offered salvation and remission of sins to a paralytic man, based on the faith of those who brought him to Jesus, not necessarily on the faith of the sick man himself; because he was obviously incapable of professing his own faith. Therefore in like manner, Catholics who take their infants to Jesus for baptism are substituting their faith for that for the faith of their children. Another example of faith of one person guaranteeing salvation for another is found in the book of Matthew: ââ¬ËAnd when he had entered into Capernaum, a centurion approached, petitioning him, and saying, ââ¬Å"Lord, my servant lies at home paralyzed and badly tormented. â⬠And Jesus said to him, ââ¬Å"I will come and heal him. â⬠And responding, the centurion said: ââ¬Å"Lord, I am not worthy that you should enter under my roof, but only say the word and my servant shall be healedâ⬠¦Ã¢â¬ ¦Ã¢â¬ And, hearing this, Jesus wondered. And he said to those following him: ââ¬Å"Amen I say to you, I have not found so great a faith in Israelâ⬠. And Jesus said to the centurion, ââ¬Å"Go, and just as you have believed, so let it be done for you. â⬠And the servant was healed at that very hour. { Matthew 8: 5-13} Salvation for Whole Household Examples abound in the Holy Scriptures where the faith of the head of a household led to salvation of the whole household, children included. In Acts11, we read about a man being saved along with his entire household after Simon Peter had preached the gospel to them. ââ¬Ëâ⬠¦. And he described for us how he had seen an Angel in his house, standing and saying to him: ââ¬ËSend to Joppa and summon Simon, who is surnamed Peter. And he shall speak to you words, by which you shall be saved with your whole house. ââ¬â¢ And when I had begun to speak, the Holy Spirit fell upon them, just as upon us also, in the beginning. ââ¬â¢ {Acts 11:13-15} Therefore, Catholics take the informed Biblical view that since a whole household can be saved by the profession of faith of the head of the house and consequently all members of the household are baptized including little children, the Bible supports the Catholic practice of baptism of infants. Authority from Church Accepted Tradition The second major source of authority for the Catholic practice of baptizing infants is the accepted practice dating back to the very beginning of Christianity, the Apostolic Church. Right from the earliest days of the Christian Church, infant baptism has been an accepted practice. One Church authority, Origen wrote in the third century AD: ââ¬Å"Baptism is given for the remission of sins; and according to the usage of the Church, Baptism is given even to infants. And, indeed, if there were nothing in infants that required the remission of sins and nothing in them pertinent to forgiveness, the grace of Baptism would be superfluous. â⬠(Origen, Homily on Leviticus 8:3 ââ¬â AD 244) The Roman Catholic Church which succeeded the early Apostolic Church reaffirmed the correctness of the practice of baptism for infants and has continued the practice to this day. WORKS CITED Origen, Homily on Leviticus 8:3 ââ¬â AD 244 The Sacred Bible: The Acts of the Apostles http://www.catholicdoors.com/
Friday, August 30, 2019
Business Plan Coffee Shop
Coffee Shop for $ 50-100 thousand MARKET SITUATION Coffee boom that seized America, and then Portugal, has come to us. Is explained by the fact that the growing popularity of refreshing drink in the population, attracts more and more attention to this business. Existing Place of public may be divided into three categories: -Coffee house, so to speak, in its purest form, where the visitor suggest several varieties of coffee. ââ¬â Coffee house with the addition of the ââ¬Å"kitchenâ⬠, which attracts customers not only the coffee menu but also the possibility of a tasty and inexpensive meal.Most of the customers in set meals (lunches) and breakfast. ââ¬â Coffee Shop ââ¬â a bookstore, a favorite place of party intellectuals:writers, journalists and inveterate book lovers. Over coffee here it is possible read your favorite book or learn the news of the book market. Should be distinguished from the usual coffee cafe. First, Coffee Shop offers enhanced assortment number co ffee and coffee prepared on the basis of drinks. Second, this place is more democratically and offers a pleasant leisurely conversation.Therefore the future owners of such establishments need to be prepared for the fact that customers will stay long here longer than in a normal cafe. Idea, concept First, you need to pay attention to the development of of the concept the institution. This is the cornerstonewhich in many respects determines the success of coffee. In the interior fast-service places emphasis on of coffee as the primary attribute. Place your bets on impeccable service, delicious cuisine original design dishes offered, unusual interior decoration disciplined waiters and special mood.Visitors have to want to return to the coffeehouse and on. It will be a classic style. How much it costs According to experts, in order to open kofeynyuna 20-30 seats in business need to invest at least $ 50 thousand. Payback period of coffee ââ¬â 1,5-3 years. Licensing documentation Pack age permits to open a coffee shop and a cafe or restaurant is no different. Need a patent for trading activities, the certificate of registration. On the ââ¬Å"documentaryâ⬠aspect of the matter will go 3-6 months. Is assumed to replan and renovation of premises.It is necessary make the reconstruction project. It is also necessary have the consent of Division for the improvement, sanitary station and firefighters. ADVERTISEMENT For promotion of coffee would need about a year in which to be active advertising support. Important area adjacent to the institution. Coffee Shop ââ¬â setting more local value if it does not differ exclusive assortment. LOCATION To estimate the location of the future coffee use the the following criteria. Stream of customers.No one will argue that the center is of the city ââ¬â the most profitable place for such institutions. A huge number of people who work there, just walking, can provide a comfortable existence no one coffee shop. Characteri stics of the competition. Question should be askedand which facilities are close to the coffee shop of the future? If it intersects the assortment and pricing policies with the majority of potential neighbors, it is better to think about a different area. { Because recapture clients from working and already gained popularity competitors always extremely difficult. }
Thursday, August 29, 2019
Human Resource Management Compensation Essay Example | Topics and Well Written Essays - 1250 words
Human Resource Management Compensation - Essay Example All other benefits offered are standard as per our company policy. Since he is currently in Austin, Texas, I have factored him a Relocation Allowance for the move. Designs, develops, and tests all aspects of electrical components, equipment, and machinery. May use computer-assisted engineering and design software and equipment to perform assignments. Applies principles and techniques of electrical engineering to accomplish goals. Requires a bachelor's degree in engineering and 4-6 years of experience in the field or in a related area. Familiar with a variety of the field's concepts, practices, and procedures. Relies on experience and judgment to plan and accomplish goals. Performs a variety of complicated tasks. May report to an executive or a manager. A wide degree of creativity and latitude is expected. Performance Bonus is paid in addition to your base salary. The Performance Bonus provides an annual lump sum payment based on yearly business results and individual contributions. By linking earnings to individual, team, and company results, the Performance Bonus "pays for performance." Employee Stock Purchase Plan: Employees have the option of purchasing company stock at a discounted rate of 6% of the market price as on the date of purchase. Stock is purchased through convenient payroll deductions, to a maximum of 10% of an employee's salary. Bi-weekly contributions will be made... Electrical Engineer III Designs, develops, and tests all aspects of electrical components, equipment, and machinery. May use computer-assisted engineering and design software and equipment to perform assignments. Applies principles and techniques of electrical engineering to accomplish goals. Requires a bachelor's degree in engineering and 4-6 years of experience in the field or in a related area. Familiar with a variety of the field's concepts, practices, and procedures. Relies on experience and judgment to plan and accomplish goals. Performs a variety of complicated tasks. May report to an executive or a manager. A wide degree of creativity and latitude is expected. Source: Salary.com Compensation package Base Salary: Base salary is the compensation that employees are paid bi-weekly. Your base salary will be $85,460 comparable with industry standards for similar positions. Incentive plan: Merit pay plan: This will provide increases to the base salary based on your performance rating and contributions to the success of the projects undertaken. Performance Bonus: Performance Bonus is paid in addition to your base salary. The Performance Bonus provides an annual lump sum payment based on yearly business results and individual contributions. By linking earnings to individual, team, and company results, the Performance Bonus "pays for performance." Stock Plan: Employee Stock Purchase Plan: Employees have the option of purchasing company stock at a discounted rate of 6% of the market price as on the date of purchase. Stock is purchased through convenient payroll deductions, to a maximum of 10% of an employee's salary. Benefit plan Pension Plan: Bi-weekly contributions will be made to the individual's account based on earnings and years of
Wednesday, August 28, 2019
Descartes Essay Example | Topics and Well Written Essays - 1250 words
Descartes - Essay Example What are the sources of epistemology? What are the limits and structure of epistemology? If it is considered as a study of justified belief (JB), epistemology deals to reply to such questions as: How are we able to comprehend the idea of justification? What are the factors which make these justified beliefs justify? Is this justification external or internal to oneââ¬â¢s own mind? Broadly comprehend epistemology deals with issues of dissemination and creation of knowledge in specific areas of question. This paper talks about what epistemology is, how it relates to justified belief, what is justified belief and explains the project of Descartes. (Audi, 1993) There are several types of knowledge: recognizing how something can be done (for instance, how can you ride a bicycle), knowing anyone in person, and knowing about a city or a place. Even though such type of knowledge consists of epistemological interest too, we shall emphasize on the knowledge of propositions and also relate t o such type of knowledge by means of the schema ââ¬ËS knows pââ¬â¢, in which ââ¬ËSââ¬â¢ is the subject who has all the knowledge and ââ¬Ëpââ¬â¢ stands for the proposition that is known to us. Now our query will be: What are the compulsory and adequate criterions for S to know that p? We may broadly differentiate, between a non-traditional and traditional approach used in responding to this question. We shall relate to them as ââ¬ËNTKââ¬â¢ and ââ¬ËTKââ¬â¢. (Audi, 1993) Pertaining to TK, the knowledge that p is, at least roughly, justified true belief (JTB). Fake and bogus propositions cannot be identified. Thus, knowledge needs truth. The scheme S does not even consider cannot be a scheme that S knows. Thus, knowledge needs belief. Finally, Sââ¬â¢s being right in thinking that p might just be a matter of good luck. Consequently, knowledge needs a third element as well, conventionally recognized as justification. Now we come at a tripartite psychoanaly sis of knowledge such as JTB: S also knows that p if and only if p is genuine and S is also justified in supposing p. This analysis talks about three conditions- belief, truth, and justification- are independently essential and collectively enough for knowledge. (Armstrong, 1973) At first, we were saying that the function of justification is just to make sure that Sââ¬â¢s belief is not correct just because of luck. On this instance, NTK and TK are in mutual agreement with each other. TK and NTK do move away from each other from each other as soon as we go on to be more precise about faithfully how justification is to accomplish this role. Pertaining to TK, Sââ¬â¢s idea that p is genuine not just because of luck when it is true or reasonable, from Sââ¬â¢s own viewpoint, to keep p to be genuine. Now according to the theory of evidentialism, what comprises a belief is justified in this logic is the control of complete proof. The primary idea is that a belief is justified to th e extent that it fits the evidence provided by S. On the other hand, NTK imagines the responsibility of justification in a different sense. Its work is to make sure that Sââ¬â¢s belief has a very high purpose of truth and thus, if genuine, is not true just because of luck. One famous plan is that this is done if, and only if, a belief is created in consistent cognitive faculties or processes. This view is called reliabilism. (Axtell, 1997) The Descartes project is a tripartite psychiatry of knowledge as JTB is sometimes known to be unfinished. These are the instances of JTB that contradict with cases of knowledge. Therefore, JTB is not enough for knowledge. Such cases are known as Gettier cases and they happen because n either the inauguration in reliable powers is enough for making sure that a belief is not genuine just due
Tuesday, August 27, 2019
Literature and culture Research Paper Example | Topics and Well Written Essays - 2000 words
Literature and culture - Research Paper Example The theme affects and is affected by the motive of the writer; thus one can say that the end a writer seeks to attain is what forms the theme of the literary work. One can imagine that there have been so many ends that have been achieved by writers throug literature. The theme therefore has an effect on the extent to which one can market his or her books to readers. Background of Authors Leon Uris was born in the United States and he moved to Israel after serving in the US Marine and in Israel, he worked as a journalist and reporter (Lambert 50). In a biography, Nadel (93) examined that Uris sought to revive his Jewish identity and that is what made him take on research into the founding of the State of Israel and most of those findings influenced his book, Exodus. Khaled Hosseini on the other hand was born in Afghanistan to an aristocratic Pusthun family around the time that the protagonist of his Kite Runner, Amir was born. Hosseiniââ¬â¢s family had to leave Afghanistan for Euro pe during the Soviet invasion. They returned briefly and then went back to the United States where he has lived to this very day (Hosseini Personal Website) This therefore suggests that both writers had an inherent interest in the history of their nations and they were therefore influenced by the history and culture of their countries. Elements of History & Non-Fiction in Theme The narrations employed in the works of these authors make a person wonder if the work was actually non-fiction or fiction. Leon Uris states in the opening page that ââ¬Å"Many events in The Exodus are a matter of history and public records. Many of the scenes were created around historical incidents and used as a backdrop for the purpose of fictionâ⬠(Uris 1). This shows evidence that Uris uses characters of fiction to portray elements of the founding of the nation of Israel, its culture and history through fiction and art. The hint that Hosseini gives in his book about the role of history in his narra tion is found in the opening statement he makes in Kite Runner saying ââ¬Å"I became what I am today at the age of twelve on a frigid overcast day, in the Winter of 1975â⬠¦ that was a long time ago but it is wrong what they say about the past Iââ¬â¢ve heard, about how you bury it because it claws its way outâ⬠(K. Hosseini 4). This suggests that Hosseini was using elements of narration to present a historical point of view of his people and community. Afghanistan & Israel through the Writers Khalid Hosseini & Leon Uris both bring out the historical injustices meted out to their peoples through the individual experiences of their characters to express the collective suffering and elements of their peoplesââ¬â¢ history and culture. This is done through fast paced narrations and very rigourous and clear pictures presented by these writers. In Kite Runner, Hosseini presents Amir as a young member of the well-to-do Pushtun family who has all the privileges and luxuries an d is seen to be righteous and innocent. Amirââ¬â¢s father, Baba is presented as a very rich aristocratic Pushtun merchant who was ready to face to advancing Soviets with courage. On the other hand, Hassan and his father, the
Monday, August 26, 2019
Queations Article Example | Topics and Well Written Essays - 250 words
Queations - Article Example To strengthen childââ¬â¢s existing capability is the good choice. Planned ignoring of the naughty child will have some salutary effect on the disposition of the child. Control, coercion and bribery need to be applied in a well-proportioned manner. Parents and teachers must share the responsibility to translate the well-researched set of tools to manage classroom behavior. Q.4.In the screening committee Mary owns prime responsibility. She knows about the ground realities about the day to day handling of children in the classroom environment. The counselor, with his knowledge about the psychological disposition of children should be able to give advice to identify a child having special needs and exceptionalities. The Principal, generally an individual with vast administrative experience, should be in a position to ensure that the student has the support and resources necessary to be successful and to reach his or her full potential. Parents are free to point out any shortcomings in the administration of their child and suggest modifications/improvements in the teaching technique. The final goal of the screening committee is the proper identification of the childââ¬â¢s learning needs. Q.5.The class as a whole was good and accepted her reformation methods, except five or six children, who had severe learning difficulties. Tim was a child with difficult home life and was mostly brought up at a childcare center. He was unable to change for the better and his initial response to her teaching methods was to cry and say, ââ¬Å"Im no good. Im stupid. I cant do this work." But his self-pity soon turned to anger toward Mary and he yelled during a parent-teacher meeting, "Im going to kill you, I hate you, and Im going to kill you." Q.6.The responsibilities of the parents at home and the teacher at school to handle the child are different. Parents generally turn a blind eye to the discipline issue of their children as their feelings are coated
Sunday, August 25, 2019
Collapse Paper Assignment Example | Topics and Well Written Essays - 500 words
Collapse Paper - Assignment Example Emergency medical evacuations will not be handled within the required time and paramedics will have a hard time navigating the streets in order to attend to patients. This paper will explore the possibilities of such an eventuality and propose a system that will counter its effects. Generally human populations want to thrive in a healthy environment and with it come the constant need to create opportunities that would help them realise the same. With the current trends of industrialisation and the use of fossil fuels human race survival is threatened more so their health and land resource from which life is derived. In this regard technology can come in handy by coming up with a system that could help civilizations adapt to the global change. In the case of the global health being threatened in a congested and developed city by climate change the system should be able to create a quick link between the patient and hospital. It should be able to depict the patientsââ¬â¢ exact location and condition to facilitate speedy access and help. The system will comprise of three major components located at three different points. First the patient will be equipped with a temper proof wrists watch capable of monitoring normal body functions in this case heartbeat, respiration and blood pressure. This information will be relayed via radio to a central station/ database in this case the hospital where computers will interpret the data and signal a warning in case of any anomaly in the vital systems. Based on the complexity of the patients medical history which is stored in a remote database the wrist watch will either warn the patient and advice on steps for treatment or alert a medical team. In the case of patient being advised the system will automatically send a message to the patients regarding their status and refer them to the nearest health institution where they can be attended
Saturday, August 24, 2019
The Legal Profession in the United Kingdom Essay
The Legal Profession in the United Kingdom - Essay Example Infact, it was these very men of the cloth who first put forward the idea of a legal profession, which encompassed the right of litigious representation in the courts of law (Encyclopaedia Britannica.) In the mean time, the native common law started to evolve under the aegis of a legal society called the Inns of Court (Encyclopaedia Britannica). However, unlike today, this institution did not furnish any special or formal courses for polishing the young entrants to be the legal practitioners (Encyclopaedia Britannica). In fact, the members of this institution acquired the skills and the rights to become the legal practitioners through experience and apprenticeship (Encyclopaedia Britannica.) Thus during the course of time, there developed a whole new range of legal agents in the UK. There were Serjeants who were considered to be the most elite of the advocates (Encyclopaedia Britannica). Then there existed the attorneys who enjoyed a legal validity and under whom served many apprentices (Encyclopaedia Britannica). These apprentices, as they gained experience with time, were alleviated to the post of barristers (Encyclopaedia Britannica). With the establishment of the Courts of Chancery in the 16th century, solicitors were recognized as the valid agents of law, though the serjeants and the barristers still managed to retain the right of advocacy in the courts (Encyclopaedia Britannica). However, the legal profession in the UK ... century, the attorneys and the solicitors were literally chucked out from the Inns of Court and the schism between the role of the advocates and the attorneys became more apparent (Encyclopaedia Britannica). In the due course of time, all the barristers working in the UK were given the name solicitor, who rather willingly agreed to serve the clients under the authority and tutelage of attorneys (Encyclopaedia Britannica). Thus, by this time, there existed only two types of legal agents in the whole of UK, which were the solicitors and the attorneys, and the demarcation of their roles become more stern and rigid than ever before.However, today the structure of the legal profession in the UK comprises of two branches that is the solicitors and the barristers. To put it simply, the role of the solicitors is primarily confined to extending legal advice to ones client, whereas the barristers actually represent their clients in the court rooms. That is, solicitors prepare and compile the p aperwork associated with a case while the barristers fight the case on behalf of their clients in the courts of law. Solicitors perform a variety of jobs for their clients that may include: Drafting and managing all the legal correspondence on the behalf of a client. Rendering and extending legal advice to the clients regarding the legal issue being faced by them in a given scenario. Extending the advice to the clients regarding the family law issues being faced by them that may include divorce, separation, child custody, division of assets, etc. Drafting the legal documents like contracts and agreements for business firms and corporations. Drafting of will for the clients. Conveyancing that is imparting legal advice and compiling and drafting the paper work for the
Research a topic about an artist, an art style, a period in art Essay
Research a topic about an artist, an art style, a period in art history, a particular type of visual art - Essay Example The first artistic period that should be carefully examined as called the Blue Period. It lasted several years from 1901 to 1904 and features depressive pictured that were painted primarily using blue color. It is argued that ââ¬Å"the Blue Period was a direct result of his friendââ¬â¢s deathâ⬠(Walther 15). Indeed, a close friend of Picasso died and the famous painter found a way to express his grief with the help of art. The next period that one may want to explore carefully is often called the Rose Period. It lasted for two years, but it was incredibly fruitful. Just like with the previous period, the major color that dominated the majority of the paintings, but rose, but the tone of the works of art was absolutely different. It often included harlequins which is largely seen as the symbol of Picasso that he put in his paintings. The third period in his artistic development is a transitional one. Nevertheless, it was able to provide the world with fabulous masterpieces. The name for it is the Black or the African period and it lasted for three years: from 1906 to 1909. Indeed, at this time the technique of Picasso has been largely influenced by the African art, especially the masks that the African tribes created. In addition to that, it is largely regarded as the period of time when the artist developed his first understanding of cubism. The period that preceded is largely one of the most important and one of the longest ones. It lasted from 1909 to 1917 and the general term that is given to it is cubism. However, it is important note that within cubism, there have been several periods as well. At first Picasso changed the shapes of some objects while depicting the reality. Afterwards, during analytic cubism, the reality was carefully examined and presented as a mechanical aggregation of geometric shapes. Finally, the synthetic cubism often presents the object as easily recognized symbols, but in distorted order. Starting from 1917
Friday, August 23, 2019
Land law coursework Essay Example | Topics and Well Written Essays - 1000 words
Land law coursework - Essay Example The law in general can take various forms like land law, property law, criminal law, constitutional law and administrative law among others. The rule of law, as is has been perceived, is always better for the society compared to the law of any individual. It is observed in the case that Teresa has won a huge sum in the lottery. She decides to make certain investment with the amount that she has own. With that intention, she purchases a Splendour House at the middle of the town. The house that Teresa has purchased was in the sole name of James. As it is said in the case that house was duly transferred to Teresaââ¬â¢s name in the month of August of 2009 and was also registered in her name. Therefore, as it applies from the course of events that it is a mere straight forward case in favour of the new owner, Teresa. But that is not the case. There are three different parties involved those have interest with the Splendour House and they claim to have certain rights upon the house. Roberta is the step mother of James. Though step mother, it seems from the case that she has stable relationship with James, the previous owner of the Splendour House. Roberta has been an independent and wealthy lady by herself. Her relationship with the house is that she often comes to the house to stay as and when she feels that she needs a break from her husband, Edward, as they are not having the best of the relations. Her interest of the house is also guided by the fact that she had contributed almost 25 % of the purchase price at the time of the purchase of the house by James. Also, it is clarified that an express trust was drawn up for her interest. Now the question is that whether Roberta still holds her right even after the house is sold to Teresa. Though, Roberta helped James while the purchase of the house but the fact is that the house was in the sole name of James. There is no legal document
Thursday, August 22, 2019
The abortion debate Essay Example for Free
The abortion debate Essay Abortion, the premature expulsing of an unborn child from the womb, is one of the most hotly debated issues of our time. On one side of the argument there is the pro-choice community who believe that abortion should be available to all women, and on the other there is the pro-life community who believe that it is the murder of an innocent human. Deciding what side is correct depends on an individualââ¬â¢s religious, scientific and ethical views. Key issues include the moral status of the unborn child, and whether its rights outweigh the motherââ¬â¢s. In examining this multifaceted debate, a good place to start is the Christian perspective. Many of the early church fathers had an existentialist view, where the foetus progressively becomes a person over time. Some are influenced by St Thomas Aquinas who identified the moment of ââ¬Ëquickeningââ¬â¢ as the decision point of development. This key moment is also significant for the formation of the brain and the first appearance of the ââ¬Ëhuman iconââ¬â¢, when the foetus begins to look like a human being. Personhood is the main issue here. Humans are beings with human tissue, but persons must have moral status. For example, a baby without a brain could be regarded as a human but not a person. The question of whether or not abortion is murder depends on your definition of personhood. With todayââ¬â¢s scientific advancements most Christians no longer accept the views of Aquinas and Aristotle on abortion. Dr. Landrum Shettles, sometimes called the father of In Vitro Fertilization, wrote, ââ¬Å"Conception confers life and makes that life one of a kind.â⬠As with all issues, Christian turn to the Bible to defend their position. Christians believe in the sanctity of life, meaning that all human life is created in Godââ¬â¢s image and has intrinsic worth. The most important verse they turn to is part of the Decalogue: do not kill. At face value this may include abortion, but on the other hand, it doesnââ¬â¢t cover the killing of animals or killing in battle. It may not be as absolute as Christians make out. Other verses include an instance in Luke when John the Baptist recognised the presence of Jesus before he was born; this suggests that unborn children are alive and have a degree of awareness before they are born. To quote John Calvin, ââ¬Å"If it seems more horrible to kill a man in his own house, then in a fieldâ⬠¦it ought surely to be deemed more atrocious to destroy a foetus in the womb before it has come to light.â⬠Christian opinion is divided between liberal and conservative perspectives. Conservative churches such as the Roman Catholic Church and the Free Presbyterian Church are against abortion. They believe abortion is murder of the innocent and have respect for human life right from conception. The Catholic Church has an essentialist view of abortion that does not allow for exceptional circumstances, even rape. In the Humanae Vitae of 1968 Pope Pius VI said, ââ¬Å"human life is sacred.â⬠This was followed up with the Declaration on Procured Abortion, 1974, where it states that womenââ¬â¢s rights, though good in themselves, cannot be an excuse for abortion when it denies another person the fundamental right to life. On the other hand, some churches have more liberal views. The Methodist Church of Ireland released a document in 2012 that outlines their support for abortion in some circumstances: when the motherââ¬â¢s life is at risk; when her mental or physical health is at risk; in cases of rape and incest and fatal foetal abnormalities. They believe that their view is the most compassionate towards both the mother and child. They do, however, emphasise that they are against abortion on demand. The crux of the document is that while Christians may not agree with abortion, we should respect the separation of church and state when it comes to abortion law. Moving on, abortion is a situation of conflicting rights ââ¬â many that are pro-choice believe that the rights of the mother are more important than the rights of the child. Proponents of situation ethics would believe that we should look at the circumstances behind an abortion, not the morality of the act. The Church of Englands position that abortion is evil but may be the lesser of two evils is consistent with a situationist approach. Difficult circumstances include when a woman has been raped. There are traumatic and involuntary circumstances surrounding the conception and the continuance of this unwanted pregnancy may well continue the trauma for the mother and her existing family. The foetus should have no claim on the woman unless the woman has consented fully to being pregnant. Another circumstance where a proponent of situation ethics would support abortion is if the motherââ¬â¢s life is at risk ââ¬â surely it is better to save one life than lose two. Natural law would generally prohibit abortion. Supporters of this theory see the act of sexual intercourse as an efficient cause that brings about the final cause of the production of a human being. Abortion prevents the final cause from being achieved and is therefore immoral. However, there is the doctrine of double effect. While it may be morally permissible to perform a good action that may have a bad outcome, it is morally impermissible to perform a bad action with a good outcome. The theory of natural law states that you are only responsible for the immediate consequences of your actions, but not for secondary or unintended effects of your action. An example of this could be abortion: it may permit indirect therapeutic abortion (such as treating cancer, which may cause death of the foetus) but not direct therapeutic abortion. Prolife Christians often use the acronym SLED when arguing against abortion. This stands for size, level of development, environment and dependency. Starting with size, pro-lifers argue that it is wrong to discriminate against the unborn due to their size. Level of development means that the only difference between the unborn and us is that they are not as developed, but the toddler is not as developed as the adult. This does not mean the toddler is any less. Environment refers to the fact that just because the unborn is within the uterus, that does not mean it has no rights. Why should a 7-inch journey down the birth canal make a difference? Finally, dependency means that just because the unborn is dependent on its mother, it does not imply it should be allowed to be killed. A disabled person may be dependent on others but this does not mean we have the right to kill them. Abortion is much more likely to be supported within the secular realm. Ethicists such as Singer have a utilitarian view of abortion. Singer hold to Preference Utilitarianism which promotes that the preferences of individuals are taken into account except where they come into direct conflict with the preferences of others. For example, if the foetus was diagnosed with a fatal abnormality abortion may be the option that would cause the greatest amount of happiness for the greatest amount of people. If the parents go through with the pregnancy they will have to suffer the trauma of watching their infant die, or go through a stillbirth. Feminists are usually on the front line in the fight for reproductive rights. They believe women and men are not truly equal until a woman has access to abortion on demand. Some would even support viewing abortion as little more than a method of contraception. A notable feminist is Judith Thomson, author of ââ¬Å"A Defence of Abortionâ⬠, uses abstract analogies to promote abortion. One of these is the violinist scenario. In this scenario a woman finds herself involuntarily chained to a famous violinist in a hospital. The violinist is dying and the woman was discovered to have the correct blood type to save him. Therefore she was kidnapped and is now acting as a life support. Thomson asserts that the woman has no moral obligation to remain connected to the violinist, and if she did it would be an extraordinary act of kindness. However, Singer claims that a utilitarian outlook would imply that one is morally obliged to stay connected to the violinist. Ultimately, in countries where abortion is legal abortion should be the choice of the mother. However, abortion is not without its dangers, such as damage to the uterus as well as depression and guilt. With this in mind, abortion may not be as safe as many believe.
Wednesday, August 21, 2019
The Role Of The Entrepreneur
The Role Of The Entrepreneur Previous studies have highlighted the changes by OECD countries from large companies consisting of mass production to smaller companies focusing on knowledge, initiative and flexibility. According to Karlsson et al, this change appears to have taken place from the mid-1970s to the early 1990s. (Karlsson et al., 2004; Acs, 1996 and 1999; Acs and Audretsch, 2001; Audretsch and Thurik, 1997 and 2001; Audretsch et al, 2002) The large managed economies invested in production, distribution and management. (Chandler, 1990) A large distributional network meant the products could reach large market. The smaller entrepreneurial economies focus on knowledge and flexibility as part of production. (Karlsson et al., 2004) Karlsson et al highlights the factors that caused the change from a managed economy to an entrepreneurial economy such as increased global competition, changes in demand and demographics, intensified uncertainty and new technologies. (Karlsson et al., 2004) Definition of Entrepreneurship The name Entrepreneur can be used very vaguely as it can cover a number of different roles. Thurik and Wennekers identified up to thirteen roles that the entrepreneur can be responsible for: The person who assumes the risk associated with uncertainty The supplier of financial capital An innovator A decision maker An industrial leader A manager An organiser and coordinator of economic resources The owner of an enterprise An employer of factors of production A contractor An arbitrageur An allocator of resources among alternative uses The person who realises a start-up of a new business (Thurik Wennekers, 1999) After much studying regarding the history of entrepreneurship and the economy, Hà ©bert and Link came up with the following definition for the entrepreneur: The entrepreneur is someone who specialises in taking responsibility for and making judgemental decisions that affect the location, form, and the use of goods, resources, or institutions. Thurik and Wennekers then came up with the following definition of entrepreneurship, with the help of Hà ©bert and Link (1989), Bull and Willard (1993) and Lumpkin and Dess (1996): Entrepreneurship is the manifest ability and willingness of individuals, on their own, in teams, within and outside existing organisations, to: perceive and create new economic opportunities (new products, new production methods, new organisational schemes and new product market combinations) and to introduce their ideas in the market, in the face of uncertainty and other obstacles, by making decisions on location, form and the use of resources and institutions. (Thurik and Wennekers, 1999) The Global Entrepreneurship Monitor (GEM) defines entrepreneurship as: Any attempt at new business or venture creation, such as self employment, a new business organisation, or the expansion of an existing business organisation by an individual, teams of individuals, or established businesses. (GEM, 2002) Invest NI simply defines entrepreneurship as: Someone who pursues business opportunities beyond known resources to create wealth. (Invest NI) History of Entrepreneurship Entrepreneurship and Economic Growth Theories Thurik and Wennekers split the historical entrepreneurial theories into three traditions: German tradition of von Thà ¼nen, Schumpter and Baumol Entrepreneur is the creator of instability and creative destruction. (Neo-)classical tradition of Marshall, Knight and Schultz Helps markets reach an equilibrium by carrying out entrepreneurial activities. Austrian tradition of Menger, von Mises and Kirzner The ability of the entrepreneur to realise opportunities for profit. Helps satisfy needs or improve market inefficiencies and deficiencies. Thurik and Wennekers attribute economic growth through entrepreneurship to three main entrepreneurial activities, enhanced competition, innovations and employment growth through firm start-ups. The following table, created by Thurik and Wennekers, shows the various schools of growth theory with the role of entrepreneurship: Growth Theories Neo-Classical Growth Theories Schumpeter/ Baumol Theory Karlsson et al highlights that the German traditions of Schumpeter in 1934 and Baumol in 1968, shows the entrepreneur as an innovator and inspirer, the implementer of creative destruction, creating instability, disequilibria and economic development. (Karlsson et al., 2004) A model by Aghion and Howitt tries to explain how creative destruction works. The Research and Development sector invents new production techniques, putting other techniques beyond use. As this new technique is used, the innovators are rewarded until a new technique superseeds his invention. (Aghion and Howitt, 1992; Thurik and Wennekers, 1999) Neo-Classical Theory While there have been a number of neoclassical growth models created over the years, the main one to have an impact has been that of Robert Solow in 1956. One of his main conclusions was that the accumulation of capital cannot account for historic growth per capita, nor the differences in international per capita output. Karlsson et al explains that the model is built where output is a function of capital and effective labour, where effective labour includes the knowledge and effectiveness of the labour force. Output therefore increases if either capital or effective labour increase, and with given levels of capital and labour, the only way growth can occur is through the expansion of knowledge, being the advancement of technology. The economy will eventually reach equilibrium, where output, capital and effective labour will all grow at a constant rate. This rate of growth is determined by the advances in technology. With this theory by Solow, the entrepreneur does not exist. Austrian Theory The Austrian Theory is where the entrepreneur spots an area of disequilibrium and attempts to profit from this situation by improving on the inefficiencies and deficiencies in the market. (Kirzner, 1973) Holcombe (1998) and Minniti (1999) agree that in order for opportunities to become available, they have to have been created by other entrepreneurs. Quite simply put by Karlsson et al, entrepreneurship generates more entrepreneurship. (Karlsson, 2004; Holcombe, 1998; Minniti, 1999) Endogenous Growth Theories (New Growth Theory) The Endogenous Growth Theory or New Growth Theory was developed in the 1980s as a response to the basic Neoclassical Theory of Growth. Many believe that the problem with the Neoclassical theories is that as growth is determined through the levels of technological changes, there is very little relating to the factors that affect technological progress. Romer (1986, 1990) and Lucas (1988) were responsible for the early development of this concept. (Hoque) It appears that generally within the endogenous models such as Romer (1986, 1990) and Lucas(1988), the entrepreneur does not hold a central role, however, Grossman and Helpman (1991) suggest that all Research and Development and investment decisions are made by forward-looking profit maximising entrepreneurs. (Karlsson et al, 2004; Grossman and Helpman, 1991) Hoque goes on to suggest that output and growth are dependent on the internal variable saving rate, which is converted into human capital investment used for innovating new ideas and methods. This variable saving rate allows for technological progress, resulting in the long-term growth of the economy. The endogenous growth theory focuses on a number of factors, including education, knowledge, research, training and experience. These factors help for growth and lead to innovation. Hoque mentions two types of innovation: Horizontal Innovation The Research Sector develops a variety of goods leading to a spillover effect on the economy. These goods can be patented and sold to the immediate goods sector who then have a monopoly power on each design and can therefore earn a monopoly return. Vertical Innovation This is where improvements are made to existing products, leading to a temporary increase in productivity and a sustainable increase in output growth. East Asian Miracle: 1965 1990 Thurik and Wennekers (1999) refers to the economic growth of East Asian countries in the past decade. These eight countries are referred to as the High-Performing Asian Economies (HPAEs) and include the Republic of Korea, Taiwan, Singapore, Hong Kong, Japan, Indonesia, Malaysia and Thailand. During the period of 1965 to 1990, they experienced an average GNP growth rate per capita of 5.5%. This growth can be taken from both exports of goods, as well as domestic demand. A number of public policies led to growing physical and human capital, the allocation of resources to productive investment and the gathering and perfecting of technology. Thurik and Wennekers, however, state that the innovation, private investment and marketing does not necessarily come from entrepreneurial activity and there is no obvious proof of an increase in entrepreneurship. Phelps commented on the paper by Mankiw (1995), claiming that with such an increase in human capital, entrepreneurship must be the reason, helped by the governments. Porter (1990) has also supported this viewed when writing about Emerging Korea in which he states two factors, being the willingness to take risks and the intensity of competition. Entrepreneurship and the Competitive Advantage of Nations An analysis by Porter (1990) was conducted in order to highlight the factors or conditions and determine the competitive strength of nations. Porters model was made up of four sets of factors in what was called the diamond model. Thurik and Wennekers describe these determinants below: Factor Conditions Porter distinguishes basic factors (e.g. natural resources and cheap, unskilled labour) from advanced factors (highly skilled personnel, modern networks infrastructure); Demand Conditions These have three main elements: the nature of buyer needs (e.g. sophisticated instead of basic), the size and the pattern of growth and the existence of mechanisms by which a nations domestic preferences are transmitted to foreign markets; Related and Supporting Industries The presence of internationally competitive supplier and related industries stimulates rivalry and partial cooperation; The Structure and Culture of Domestic Rivalry This encompasses a wide scope such as opportunities provided to possible new entrants, the nature of competition between incumbent firms, dominant business strategies and management practices. (Thurik and Wennekers) This diamond model is summed up by Porter (1990) as, Invention and entrepreneurship are at the heart of national advantage. With this model, Porter suggests that innovation comes directly from entrepreneurship. As well as this, he claims that international competitiveness is a vital link between entrepreneurship (innovation) and economic growth, with domestic rivalry being important in leading to international competitiveness. He also mentions that entrepreneurship is not a trait associated with smaller firms. (Thurik and Wennekers, 1999) Evolutionary Economics The concept of this theory is that each individual has a set of routines, which gradually evolve. These routines are tested in the market environment and due to natural selection, the most suitable one survives. (Karlsson et al., 2004) In this model, each individual has entrepreneurial spirit, human capital and venture capital. (Grebel et al., 2001) Eliasson (1994) mentions that in order for a firm to survive, competence is the most important factor and that accumulation of competence is the determinant of success. This was also backed up by a study conducted by Eliasson and Braunerhjelm (1998), claiming that economic growth stems from human-embodied tacit competencies. (Karlsson et al., 2004) Linking Entrepreneurial Activities to Economic Growth Competition Within the U.S., Acs (1996) suggests that employment growth is due to the increased competition. Geroski (1994) agrees that competition is important by stating that competition plays a significant role in stimulating productivity, with both new firms and new ideas provoking movements to, and outwards movements of, the production frontier which, the data suggest would not have occurred in their absence. Gort and Sung (1999) conclude that an increase in competition will lead to an increase in efficiency. This competition will affect efficiency in four ways: Greater incentive to stimulate demand Higher quality of capital inputs Lower monitoring costs Greater efficiency of firm-specific organisational capital and rivalry leading to innovation Dennis (1995) mentions how competition stimulates some people, but not everyone. These people will try to find a better and more profitable way of doing things in order to maintain or improve their position in the market. These people have chosen innovation rather than working harder. (Dennis, 1995; However, he also mentions how there are policy-imposed limits on competition which vary from country to country, giving the example that the U.S Postal Service who are owned by the government, are the only company allowed to deliver first class mail. This can allow a monopoly to form over a certain market and prevent competition occurring. Innovation The innovative activity of small firms has a different level of importance depending on the type of sector a firm is involved in. (Acs and Audretsch, 2001) Baldwin and Johnson (1999) mention a number of small firms in which innovation is important including electronics, instruments, medical equipment, steel and biotechnology. Acs (1996) goes further than this by calculating the number of innovations per 1000 employees in different industry sectors. When this measure was carried out in 1982 in the U.S., it was found that firms with less than 500 employees produced more innovations in fields such as electronic computing equipment, process control instruments, electronic components, engineering and scientific instruments and plastic products. (Karlsson et al., 2004) In studies conducted by Acs et al (1994), as well as Audretsch and Vivarelli (1996), it was found that innovations by small firms was greater if the firms were close to Universities. This shows the effect of education on innovation. Other studies have found that small firms are more likely to innovate in unexplored areas of technology, with the larger companies focusing on more established areas. (Acs, 1999) Rothwell and Zegveld found that all outputs from the UK which they studied were radical breakthroughs, with only 27% of U.S. firms producing these radical breakthroughs, 30% as major technological shifts and 37% as improvement type innovations. (Rothwell and Zegveld, 1982; Karlsson, 2004) Ernst and Young make a number of observations with regards innovation and entrepreneurship: Theres no time like a downturn to take advantage of entrepreneurial thinking A recent Ernst and Young survey found that the majority of entrepreneurs saw the economic slowdown as the perfect time to explore new opportunities. More than half of the companies on the 2009 Fortune 500 list were founded during a recession or bear market. The market leaders of today are not necessary the market leaders of tomorrow Entrepreneurial enterprises grow quickly, replacing the market share of many dominant corporations. Innovation can, and often must be, disruptive Disruptive innovation is often the turning point for business in an industry undergoing significant change. (Christensen, 1997) Applegate states, Disruptions in the business environment cause economic shifts that destabilise industries, companies and even countries. They allow new entrants or forward thinking established players to introduce innovations in products, markets, or processes that transform the way companies do business and consumers behave. (Applegate, 2007) She goes on to mention a number of factors which companies must consider when faced with disruptive business conditions: Technology Important emerging technologies and how they are being used by others to help create an advantage. Business Models New business models need to be created or adapted to help improve how business is done. Industry Dynamics Fragmented industries where significant value can be delivered through consolidation. Globalisation Adapt to how companies in another part of the world perform. Regulatory, macroeconomic, political and societal factors Changes in regulations, political power and society that disrupt major companies, providing opportunities for new companies. (Applegate, 2007) Never too big to be an entrepreneur Large firms are often weighed down by institutional structures that may see unconventional ideas or strategies as impractical or threatening. However, they can still innovate successfully by building and sustaining innovation-oriented cultures. Large companies have found that in addition to internal research, they can seek innovation through partnerships, joint ventures, licensing and investing in up and coming companies. Government policies that encourage entrepreneurship are most likely to result in increased innovation A 2009 report from the Ernst and Young Conference Board states, Policies that protect firms or industries can result in reduced incentives for entrepreneurs to invest in innovative ideas and for large firms to invest in Research and Development because they no longer face the competitive pressure to constantly improve their product in order to improve (or maintain) their market share. Ernst and Young highlight that the governments which are viewed as most effective when they stay out of the business sectors way, play an important role in helping the engines of growth which are entrepreneurs. They also highlight some ways in which the government can help: Strengthen and invest in education systems Encourage businesses to connect with global, cross-border markets Cultivate confidence in capital markets Simplify procedures and requirements Champion robust Research and Development programs Allow for failure Encourage sound public/private partnerships Make the tax framework friendly to innovation (Ernst and Young, 2009) Industrial Structure, Start-ups and Job Creation When it comes to the differences between large and small firms, Carree and Thurik (1998), as well as Vosloo (1994) highlight a number of advantages in smaller firms. Mentioned is the fact that a greater number of smaller firms dispersed geographically allow for customers to cut travelling distances. As well as this, variety can only be created by small firms and the entrepreneur running the firm is more likely to be energetic and motivational. Vosloo highlights advantages of small firms in developing economies, such as less capital per worker on average, higher likelihood of innovation per employee, greater flexibility, higher growth and job creation rates, as well as being able to serve a more niche market. Studies by both Audretsch et al (2002), as well as Carree and Thurik (1998), have found that on average, the employment share of large firms had a negative effect on growth of output and that smaller firms have helped economic growth. With regards to Germany, Wengenroth (1999) concluded that Small business was the catalyst of industrial growth in providing the background of skills and services which alone made possible the mass consumption of industrial product. Davis et al (1996) mentions that the entrepreneurship in start-ups makes a smaller contribution to job growth than expansion of existing firms in the U.S. This is also backed by a study conducted by Bednarzik (2000). It has to be noted however, that smaller firms have a higher gross job creation, with larger firms providing more in terms of net job creation. Carree and Klomp (1996) dispute this claim from Davis et al, arguing that relative to employment share, small firms created more net jobs relative to employment share. (Karlsson, 2004) What has regularly been found is that small firms can have a volatile job situation, with plenty of job growth, but also a lot of job destruction. Investec, a UK asset management group, have predicted a large number of job losses within the public sector with the hope that entrepreneurship will offset this. Their research also found that two thirds of Britains entrepreneurs expect to increase employment, with only 8% expecting job losses. (Investec, 2010) Ed Cottrell, from Investec Private Bank highlighted what is required by the new Coalition Government in the UK. With a new government formed, severe spending cuts will have to be enforced to help tackle the countrys debts, and this could lead to job losses, especially in the public sector. We need to make sure that entrepreneurs, which are the lifeblood of our economy, are properly incentivised to grow their operations and therefore hire more people. Philip Shaw, the chief economist at Investec Bank added, Entrepreneurs look for an environment that provides them with opportunity, reward and a flexible environment to operate in. They also look for stability and support, be that from the banks or the government, and it is in the best interest of the economy to provide this to them. (Investec, 2010) Entrepreneurship and Large Firms Entrepreneurial activity is not limited to small firms. Corporate entrepreneurship occurs in large organisations with Drucker (1985) claiming that they will not survive unless they acquire entrepreneurial competence. Stopford and Baden-Fuller (1994) explain that there are three types of corporate entrepreneurship: Creation of new businesses within an organisation often referred to as intrapreneurship. Transformation or strategic renewal of existing organisations. Carrying out an innovation that essentially alters the industry. (Stopford and Baden-Fuller, 1994) He also highlights five attributes common with corporate entrepreneurship: Proactiveness Aspirations beyond current ability Team orientation Capability to resolve dilemmas Learning capacity Stevenson and Jarillo (1990) refer to corporations acting entrepreneurially, pursuing opportunity, whether through specific company structures or not, constitutes the core of entrepreneurship, both individual and corporate. They highlight how dependant management are on the individuals within a firm to create this corporate entrepreneurship. Bridge et al (1998) highlight the difference between inventors and intrapreneurship. Inventors are usually individuals, but intrapreneurship is frequently carried out by groups or teams. Thurik and Wennekers (1999) concludes by stating that corporate entrepreneurship plays an essential role in the process of strategic renewal of large and incumbent firms. In the short-term, corporate entrepreneurship can occur at the same time as downsizing and the loss of jobs, however, in the long-term, it enhances competitiveness and leads to sales growth. Thurik and Wennekers (1999) also mention how studies have shown that there seems to be a strong evidence to support a positive impact of corporate entrepreneurship on economic growth. They created a table to show the differences between individual and corporate entrepreneurship: Figure 2 Individual and Corporate Entrepreneurship According to Cole and Neumayer (2003), neoclassical growth theory predicts that poor economies grow faster than rich economies. This is taken from the theory that if all economies are assumed to have the same steady state, then the only difference between countries is the initial level of capital and poor economies will grow faster as they are further away from their steady state. Measuring Entrepreneurship GEM (Global Entrepreneurship Monitor) The Global Entrepreneurship Monitor is a global measure of entrepreneurial activity to assist in entrepreneurship policy research. The project has now been running for 12 years and covers over 34 countries worldwide. GEM aims to fulfil a number of research questions similar to this dissertation: How much entrepreneurial activity is taking place in each county? Why do levels of entrepreneurial activity differ between countries/regions? What are the links between entrepreneurial activity and economic growth and productivity? Surveys conducted by GEM are used to collect information on different types of businesses at a range of entrepreneurial activity. These three business types are: Start-ups Young businesses Establishes businesses Research from GEM continues to associate a positive correlation between start-up activity and economic development, highlighting key indicators of entrepreneurial capacity and tendencies. A Background to Northern Ireland Northern Ireland is one of four countries located in the United Kingdom. With a population of 1.7 million people as of 2004, it is the smallest of these countries. (UK Statistics Authority, 2004) Traditionally, Northern Ireland has been known for having an industrial economy, for example, in the shipbuilding and textiles businesses. This has since been replaced by the services industry. For example, Harland and Wolff, a shipbuilder located in Northern Ireland, once employed around 35,000 people. Nowadays, there are only around 500 employees focused on the repairing of oil platforms and the assembly of wind turbines. Northern Ireland has for a long time suffered from a troubled past, with the most recent referred to as The Troubles. This has been dated from the late 1960s to the signing of the Good Friday Agreement in 1998. (Aughey, 2005) During this time, threats of bombings, the high cost of security and the lack of a stable market, meant large companies were reluctant to invest. This also drove away many of the existing businesses. (Rowthorn Wayne, 1988) Confidence gradually built up within Northern Ireland since the mid 1990s, when many paramilitary groups initiated cease fires and political parties began to work together. However, the signing of the Good Friday Agreement in 1998 proved to the rest of the world that the majority of Northern Ireland were willing to move on from the troubled past. Twelve years on and unemployment has fallen sharply, as well as many people immigrating to Northern Ireland from other EU countries. (BBC, 2008) The current rate of unemployment stands at 6.8%, amongst one of the lowest of the regions in the United Kingdom, compared with a peak in 1986 of 17.2%. (DETINI, 2010) (BBC, 2001) Entrepreneurship within Northern Ireland Previous research into the effect of entrepreneurial activity on economic growth by organisations such as the Global Entrepreneurship Monitor (GEM) and the Organisation for Economic Co-operation and Development (OECD), have shown a direct correlation. (Hegarty, 2006) According to the GEM survey in 2009, Northern Ireland was ranked 9th out of 12 UK regions for Total Entrepreneurial Activity (TEA). There has still, however, been a rise in the TEA rate since 2002, despite the impact of the economic recession. (GEM, 2009) Figure 1 below shows the change in Total Entrepreneurial Activity since 2002: Figure 3 Total Entrepreneurial Activity in Northern Ireland and the UK (2002 2009) (GEM APS) This TEA value is calculated using the percentage of early-stage entrepreneurial activity among the adult population, aged 18 64 years. (Pfeifer and Sarlija, 2010) In order to qualify and be included in the TEA value, respondents have to be involved in either: Nascent Ventures The firms generally referred to as start-ups. Any respondent actively involved in creating a new business that they would own or part of and had not paid any salaries or wages to anyone for more than three months. Young Businesses More established, owner-manager businesses but have not been paying salaries for more than 42 months. Lee et al explains that there are two academic approaches to categorise entrepreneurship. The first way is to focus on the entrepreneurs and understand why they chose to start a new business and be an entrepreneur. The second way is to study regional variation in the formation of new businesses. (Lee et al., 2004) For this study, both approaches will be used. A number of factors can be studied in order to determine how entrepreneurship affects economic growth. Storey (1994) focused on factors such as personality, human capital and ethnic origin whereas Evans and Leighton (1990) focused more on factors such as educational attainment and work experience. Previous research has linked a higher educational attainment with new business formation. (Evans and Leighton, 1990) Evans and Leighton also found that men with greater financial resources and greater confidence in their ability are likely to be self-employed. (Evans and Leighton, 1989) Regional factors that affect birth rates of businesses include unemployment, population density, industrial clustering and the availability of financing. (Reynolds et al., 1994) Armington and Acs (2002) also highlighted factors such as income growth and population growth. Factors Affecting Entrepreneurship Gender Female entrepreneurial activity within Northern Ireland between 2002 and 2009 has been significantly below the UK average. In 2009, 2.4% of females were engaged in early stage entrepreneurial activity compared to the UK average of 3.7%. This value is also under a third of male entrepreneurial activity within Northern Ireland, which stands at 8%. Figure 2 shows the female early-stage entrepreneurial activity for Northern Ireland compared with that of the UK average. A report by Crimson Business Limited, highlighted possible reasons why women are less likely to be entrepreneurial than men: Under-capitalisation of ventures Low levels of self-confidence Visibility of appropriate role models The report indicates that these barriers to women becoming entrepreneurs needs to be overcome with greater support from the government. (Crimson Business Limited, 2006) These barriers are not seen globally however, with different parts of the world having different cultures and customs with regards the participation of women in the economic growth of countries. For example, in countries such as Tonga and Guatemala, women are more likely to be involved in early-stage entrepreneurial activity than men. (Bosma and Levie, 2009) Age In 2009, total entrepreneurial activity for those aged 18 24 in Northern Ireland was 2.3% of the adult population. This is compared with a UK average of 3.4%. Northern Ireland remains, as it has done in recent years, with a peak in total entrepreneurial activity between the ages of 25 and 34. A surprising decline in entrepreneurs between the ages of 35 and 44 has been seen in 2009, against the trend of the rest of the UK
Tuesday, August 20, 2019
Superconducting Transition Temperature Determination
Superconducting Transition Temperature Determination Fabrication of YBa2Cu3O7-ÃŽà ´ and Determination of its Superconducting Transition Temperature A superconducting material is one which below a certain critical temperature exhibits, amongst other remarkable traits; a total lack of resistivity, perfect diamagnetism and a change in the character of the specific heat capacity. The BCS theory describes perfectly the phenomenon of superconductivity in low temperature superconductors, but cannot explain the interaction mechanism in high temperature superconductors. In order to determine the superconducting transition temperature of two laboratory fabricated batches of YBCO their resistivity and specific heat capacity were measured as functions of temperature. From resistivity measurements the two batches were found to have transition temperatures of 86.8(Ãâà ±0.8)K and 87.8(Ãâà ±0.4)K respectively which were used to infer their oxygen contents of 6.82(Ãâà ±0.01) and 6.83(Ãâà ±0.01) atoms per molecule respectively. These agreed with XRD data and the literature upper value of the transition temperature of 95K (with an oxygen content of 6.95). Specific heat capacity measurements of the first batch gave questionable confirmation of these results, but could not be performed on the second batch due to time constraints. 19 January 2010Page 14 of 14Josephine Butler College I. Introduction and Theory A superconducting material is defined as one in which a finite fraction of the electrons are condensed into a superfluid, which extends over the entire volume of the system and is capable of motion as a whole. At zero temperature the condensation is complete and all of the electrons participate in the forming of the superfluid. As the temperature of the material approaches the superconducting transition temperature (or critical temperature, given by Tc) the fraction of electrons within the superfluid tends to zero and the system undergoes a second order phase transition from a superconducting to a normal state.[i] The phenomenon of superconductivity was first observed by Kamerlingh Onnes in Leiden in 1911 during an electrical analysis of mercury at low temperatures. He found that at a temperature around 4K the resistance of mercury fell abruptly to a value which could not be distinguished from zero.[iii] The next great leap in experimental superconductivity came in 1986 when MÃÆ'à ¼ller and Bednorz fabricated the first cuprate superconductor[v]. After its lack of resistivity one of the most striking features of a superconductor is that it exhibits perfect diamagnetism. First seen in 1933 by Meissner and Ochsenfeld, diamagnetism in superconductors manifests itself in two ways. The first manifestation occurs when a superconducting material in the normal state is cooled past the critical temperature and then placed in a magnetic field which will then be excluded from the superconductor. The second appears when a superconductor (in its normal state) is placed in a magnetic field and the flux is allowed to penetrate. If it is then cooled past the critical temperature it will expel the magnetic flux in a phenomenon know as the Meissner effect.[vi] This can be seen qualitatively in figure 1. In 1957, Bardeen, Cooper and Schrieffer managed to construct a wave function in which electrons are paired. Know as the BCS theory of superconductivity it is used as a complete microscopic theory for superconductivity in metals. One of the key features of the BCS theory is the prediction of an energy gap, the consequences of which are the thermal and most of the electromagnetic properties of superconducting materials. The key conceptual element to this theory is the formation of Cooper pairs close to the Fermi level. Although direct electrostatic interactions between electrons are repulsive it is possible for the distortion of the positively charged ionic lattice by the electron to attract other electrons. Thus, screening by ionic motion can yield a net, attractive interaction between electrons (as long as they have energies which are separated by less than the energy of a typical phonon) causing them to pair up, albeit over long distances. Given that these electrons can experience a net attraction it is not unreasonable that the electrons might form bound pairs, effectively forming composite bosons with integer spin of either 0 or 1. This is made even more likely by the influence of the remaining electrons on the interacting pair. The BCS theory takes this idea one step further and constructs a ground state in which all of the electrons form bound pairs. This electron-phonon interaction invariably leads to one of the three experimental proofs of the BCS theory. A piece of theory known as the isotope effect provided a crucial key to the development of the BCS theory. It was found that for a given element the super conducting transition temperature, TC, was inversely proportional to the square root of the isotope mass, M (equation 1). TCà ¢Ãâ ?M-12 (1)[vii] This same relationship holds for characteristic vibrational frequencies of atoms in a crystal lattice and therefore proves that the phenomenon of superconductivity in metals is related to the vibrations of the lattice through which the electrons move. However this only holds true for low temperature superconductors (a fact which will be discussed in more detail at a later stage in this section). Both of the two further experimental proofs of BCS theory come from the energy gap in the superconducting material. The first proof is in the fact that it was predicted and actually exists (figure 2) and the second lies in its temperature dependence. From band theory, energy bands are a consequence of a static lattice structure. However, in a superconducting material, the energy gap is much smaller and results from the attractive force between the electrons within the lattice. This gap occurs ÃŽâ⬠either side of the Fermi level, EF, and in conventional superconductors arises only below TC and varies with temperature (as shown in figure 3). Figure 2: Dependence of the superconducting and normal density of states, DS and Dn respectively. From Superconductivity, Poole, C.P., Academic Press (2005), page164 At zero Kelvin all of the electrons in the material are accommodated below the energy gap and a minimum energy of 2ÃŽâ⬠must be supplied in order to excite them across the gap. BCS theory predicts equation 2 which has since been experimentally proven, ÃŽâ⬠T=0=CkBTC (2) [viii] where theoretically the constant C is 1.76 although experimentally in real superconductors it can vary between 1.75 and 2.45. Figure 3: Temperature dependence of the BCS gap function, ÃŽâ⬠. Adapted from The Superconducting State, A.D.C. Grassie, Sussex University Press (1975), page43 As before stated it has been found that the first of these BCS proofs does not hold for high temperature superconductors. In these materials it has been found that in the relation stated as equation 1, the exponential tends towards zero as opposed to minus one half. This indicates that for high temperature superconductors it is not the electron-phonon interaction that gives rise to the superconducting state. Numerous interactions have been explored in an attempt to try and determine the interaction responsible for high temperature superconductivity but so far none have been successful. Figure 4: A plot of TC against TF derived from penetration depth measurements. Taken from Magnetic-field penetration depth in K3C60 measured by muon spin relaxation, Uemura Y.J. et al. Nature (1991) 352, page 607. In figure 4 it can be seen that the superconducting elements constrained by BCS theory lie far from the vast majority of new high temperature superconducting materials which appear to lie on a line parallel to TF, the Fermi temperature and TB, the Bose-Einstein condensation temperature, indicating a different interaction method. One of the most extensively studied properties of the superconductor is its specific heat capacity and how its behaviour changes with temperature (seen in figure 5). It is known that above the transition temperature the normal state specific heat of a material, Cn, can be given by equation 3 (below) which consists of a linear term from the conduction electrons and a cubic phonon term (the addition Schottky contribution has been ignored in this case and ÃŽà ³ and A are constants). Cn=ÃŽà ³T+AT3 (3)[ix] Due to the aforementioned energy gap it is also predicted by BCS theory that at the superconducting transition temperature there will be a discontinuity in the specific heat capacity of the material of the order 1.43 as seen in equation 4 (where CS is the superconducting state heat capacity) and figure 5. CS-ÃŽà ³TCÃŽà ³TC=1.43 (4)[x] However for high temperature superconductors this ratio is likely to be much smaller due to a large contribution from the phonon term in the normal state specific heat capacity. Figure 5: Heat Capacity of Nb in the normal and superconducting states showing the sharp discontinuity at TC. Taken from The Solid State Third Edition, H.M Rosenberg, Oxford University Press (1988), page 245 Now that the concept of the high temperature superconductor has been explained this report can return to one of the initial concepts of how the behaviour of resistivity changes with temperature. A low temperature superconductor is likely to obey the T5 Bloch law at low temperatures and so its resistivity will fall to zero in a non-linear region. In contrast the resistivity of a high temperature superconductor should fall to zero before it leaves the linear region. The resistivity profile of a high temperature superconductor can also be used to determine its purity. By comparing the range of temperatures over which the transition occurs with the transition temperature itself an indicator of purity can be determined (equation 5, where PI is the purity indicator and ÃŽâ⬠T the magnitude of the region over which the transition occurs). In this case a value of zero would indicate a perfectly pure sample. ÃŽâ⬠TTC=PI (5)[xi] Other than for scientific purposes, within the laboratory, the biggest application of superconductors at the moment is to produce to the large, stable magnetic fields required for magnetic resonance imaging (MRI) and nuclear magnetic resonance (NMR). Due to the costliness of high temperature superconductors the magnets used in these applications are usually low temperature superconductors. It is for this same reason that the commercial applications of high temperature superconductors are still extremely limited (that and the fact that all high temperature superconducting materials discovered so far are brittle ceramics which cannot be shaped into anything useful e.g. wires). Yttrium barium copper oxide (or YBCO) is just one of the aforementioned high temperature, cuprate superconductors. Its crystal structure consists of two CuO2 planes, held apart by a single atom of yttrium, either side of which sits a BaO plane followed by Cu-O chains. This can be seen in greater detail in figure 6. Figure 6: The orthorhombic structure of YBCO required for superconductivity. Adapted from High-Temperature Superconductivity in Curpates, A. Mourachkine, Kluwer Academic Publishers (2002), page 40 If the structure only has 6 atoms of oxygen per unit cell then the Cu-O chains do not exist and the compound behaves as an antiferromagnetic insulator. In order to create the Cu-O chains and for the compound to change to a superconductor at low temperatures it has to be doped gradually with oxygen. The superconducting state has been found to exist in compounds with oxygen content anywhere from 6.4 to 7 with optimal doping being found to occur at an oxygen content of about 6.95.[xii] This report intends to determine the superconducting transition temperature of a laboratory fabricated sample of YBCO. This will be achieved by measuring how both its resistivity and specific heat capacity vary as a function of temperature. II.I Fabrication and Calibration Methods To ensure an even firing of the sample within the furnace and to find out where in the furnace the heating profile was closest to that of the actual heating program, three temperature profiles of the furnace were taken while heating. The length of the furnace was measured with a metre ruler and found to be 35Ãâà ±1cm. Four k-type thermocouples were then evenly spaced (every 11.5Ãâà ±0.5cm) along the length of it, as can be seen in figure 7 below. Figure 7: Transverse section of the furnace. Thermocouples are numbered 1 to 4 and the length of the furnace surrounded by heating coils is shown in green, blocked at either end by a radiation shield. Temperature profiles were taken for each of the temperature programs displayed in figure 8; all started at room temperature and were left to run until the temperature displayed by the thermocouples had stopped increasing. Figure 8: Details of furnace programs used to obtain the temperature profiles shown in section III. While this was being done samples of YBCO were fabricated. The chemical equation for the fabrication of YBCO is as follows in equation 6 and the amounts of the reactants required to fabricate 0.025 mol are displayed in figure 9 Y2O3+4BaCO3+6CuIIOà ¢Ã¢â¬ 2YBa2Cu3O7-ÃŽà ´ (6) Figure 9: Quantities of reactants required to fabricate 0.025 mol YBCO. Relative molecular masses (RMMs) calculated using relative atomic masses The procedure for fabrication can be seen in figure 10 and using this technique two batches of YBCO were fabricated, the first yielded just one pellet and the second batch yielded four. Figure 10: Describes the steps taken during fabrication of superconducting YBCO samples. In order to obtain a more accurate value of the temperature within the sample space of the cryostat the resistance of a platinum thermometer was measured as a function of temperature. In order to do this a Pt100 platinum thermometer was varnished to one side of a cryostat probe and connected via a four point probe to a power source (as can be seen in figure 11), an ammeter and a voltmeter (Keithley 2000 DMMs). The ammeter and the voltmeter were connected to a computer in order that live data could be fed straight into a LabView program (appendix 2) which would record the data to both a much great accuracy and precision than could be done by a human. Although a stable and constant current was used it was felt, in the interest of good practise, necessary to add the live feed ammeter into the LabView program as tiny fluctuations in current could have potentially changed results which would not have been noticed otherwise. The probe was then placed in the sample space which was subsequently vacuumed (to a pressure of 810-4 Torr) and flushed with helium twice. The sample space was then left full of helium due to its high thermal conductivity. The cryostat was cooled with liquid nitrogen to a temperature of approximately 77K and the LabView program left to record the change in the resistance of the platinum thermometer (using Ohms law, V=IR) and its corresponding temperature (from the intelligent temperature controller or ITC) while the cryostat heated up naturally. The temperature increase function of the program was not used as leaving the cryostat to heat up as slowly as possible allowed data to be gathered over a much greater period of time which lead to a relationship with less error. This relationship was plotted in order that the temperature dependant resistance profile of the platinum thermometer could be incorporated into the LabView program for use in future experiments to determine more accura tely the temperature of the sample space. While this was being done the dimensions of the cut samples were measured using vernier callipers and weighed in order to determine a density for YBCO. Each dimension was measured six times (to reduce random error) by two different people (to reduce systematic error). The off cuts of each batch of YBCO were then sent off for X-ray diffraction analysis in order to determine the chemical composition of the fabricated samples. The diffraction was carried out using a wavelength of 1.54184Ãâ¡Ã º. II.II Fabrication and Calibration Results, Analysis and Interpretation The three temperature profiles of the furnace can be seen below in figure 12. The results are slightly skewed due to one end of the furnace having been left open in order to allow the thermocouples to sit inside the furnace. This can be seen back in figure 7. The measurements were taken by eye over a 10 second time period. It was therefore decided that the errors on the time should be Ãâà ±5 seconds and the error on the temperature Ãâà ±1K, both of which are unfortunately too small to be seen on the profiles. The data points were fitted to cubic curves as this best matched the physical behaviour of the heating. Figure 12: Temperature profiles of the furnace. The temperature of the program is shown in black crosses and the temperatures of thermocouples 1, 2, 3 and 4 are shown in yellow, red, green and blue respectively. It can immediately be seen from figure 12 that, during the initial stages of heating, the temperatures of all of the thermocouples lag behind that of the furnace program, specifically those of the thermocouples at the open end of the furnace (1 and 2). This can be accounted for due to poor thermal insulation at the open end of the furnace. It can also be seen that as the furnace reaches its required temperature and begins its dwell time the temperatures of the thermocouples continue to rise for a short duration before also levelling out. The most likely reason for this is that once the furnace reaches its required temperature the program will instantaneously cut the current to the heating coils. They will still however have thermal energy in them which will leach through the ceramic inner of the furnace into the firing space itself. Another striking feature of the profiles that can be seen is that the longer the furnace has to reach the required temperature, the more linear the increase in temperature is throughout the furnace. It was therefore deduced that had the furnace been sealed at both ends with radiation rods and covers, then the centre of the furnace would be that which had a temperature profile closest to that of the furnace program. It was also decided that in order to ensure a steady, linear rate of heating, a slower increase in temperature would be used. The masses of the batches before and after calcinations were compared and were found to have decreased by an average of 2.44(Ãâà ±0.01)% of their initial masses. This was expected as one of the by-products created during the calcination of BaCO3 is CO2 which would have been removed from the furnace during this heating period therefore reducing the mass of the compound. The weights of the samples from batch two before and after annealing were compared and it was found that each of the samples of YBCO had increased in mass by an average of 3.51(Ãâà ±0.03)% of their initial masses. This was unexpected as during the annealing process the compound is reduced and so should lose mass. One possible explanation for this could be a simultaneous reduction and oxygen doping of the compound in order to try and fill the copper and oxygen chains shown in figure 6. The densities of both batches of YBCO were calculated by weighing each of the samples from that batch and dividing their masses by their measured volumes. The densities of batches one and two were found to be 5.25(Ãâà ±0.04)gcm-3 and 3.5(Ãâà ±0.1)gcm-3 respectively. The greater error stated with the value of the density of the second batch of YBCO is a result of an error on the mean being taken whereas the error on the density of the first batch is merely propagated from those of its volume and mass as there was only one sample. When literature values of the density of YBCO were consulted it was found that the compound has a variable density of anywhere from 4.4 to 5.3gcm-3.[xiii] When comparing this range to the experimentally determined values of this parameter it was found that the density of the first batch lay just inside the range whilst the density of the second batch lay well outside of the lower end of it. One possible reason for the very low value of the density of batch two could be that its samples were left in the press for less time than batch one during sintering. All samples were checked to see whether they exhibited the Meissner effect. All did and a photograph showing this can be seen below in figure 13 The X-ray analysis of the two laboratory fabricated batches of YBCO can be seen in figure 14 below. The intensities were recorded every 0.01 degrees and then scaled appropriately using the greatest intensity in order that they could be compared to each other. As can be seen in figure 14 when both data sets are overlaid negligible differences can be seen. This indicates that both batches have almost identical chemical compositions and structure. A reasonable amount of background noise can be seen accompanied by an offset from zero intensity which changes in magnitude as the angle of diffraction increases. This can be accounted for by two factors. The first being tiny random impurities in the batches obtained by fabrication outside of a totally clean environment. The second is that small levels of the initial reactants may have not formed the required compound during calcination and annealing. A standard diffraction pattern of YBCO produced using the same wavelength of radiation was taken from The Chemical Database Service and can be seen below in figure 15. When this is compared to the patterns of the two laboratory fabricated samples in figure 14 all of the same intensity peaks can clearly be identified. This would indicate that YBCO had been successfully fabricated. Figure 15: X-Ray diffraction pattern of YBCO6. Calculation of the structural parameters of YBa2Cu3O7-ÃŽà ´ and YBa2Cu4O8 under pressure, Ludwig H. A. et al., Physica C (1992) 197, 113-122. It was expected that the comparison of standard diffraction patterns of YBCO of different oxygen contents with those fabricated within the laboratory would allow their oxygen content to be deduced. This, however, could not be achieved as all of the standard patterns of YBCO found in journals and online databases from oxygen contents of 6 to 7 had extremely similar diffraction patterns. The resistance of the platinum thermometer was plotted against temperature and can be seen in figure 16. A linear relationship was fitted to the data as seen in figure 16 which produced a reduced chi squared value of 1.317 and equation 7. T=2.4958(Ãâà ±0.0007)R+25.54(Ãâà ±0.04) (7) The reduced chi value indicates a strong linear relationship while the equation of the line gives a resistance of 99.2(Ãâà ±0.2)ÃŽà © at a temperature of 273.2(Ãâà ±0.1)K. When compared to the technical data for this component which gives a resistance of 100.00ÃŽà ©[xiv] at a temperature of 273.15K, it shows very close correspondence although not within error. A temperature of one less significant figures accuracy had to be used in this calculation due to the inability of the ITC to measure temperature to any more than one decimal place. This slight difference between the reference and experimental values of the resistance of the Pt100 at a given temperature can be accounted for by the position of the ITCs heat sensor. This lies just outside of the sample space and would cause the ITCs heat sensor to detect a small increase in temperature before it was received by the Pt100 within the sample space. Thus causing the Pt100 to lag behind in temperature (even if only slightly) and would therefore cause the slightly lower resistance for the given temperature as calculated above and can be seen as a very slight systematic error. III.I Resistivity Methods One of the cut samples was fixed to the other side of the probe to the Pt100 with thermally insulating varnish and four copper wire contacts were painted onto it with electrically conductive silver paint. The separation of each of the four wires was measured with vernier callipers six times each by two different people for the same reasons as before and recorded for later calculation. A four point probe resistance measurement was used in order to avoid the indirect measuring of resistances other than just the sample resistance. The contact resistance and spreading resistance are also normally measured by a simple two point resistance measurement. The four point probe uses two separate contacts to carry current and two to measure the voltage (in order to set up a uniform current density across the sample) and can be seen in figure 17. In a four point probe the current carrying probes will still be subject to the extra resistances but this will not be true for the voltage probes which should draw little to no current due to the high impedance of the voltmeter. The potential, V, at a distance ,r, from an electrode carrying a current, I, in a material of resistivity, à ?, can be expressed by V=à ?I2à â⠬r=à ?I2à â⠬1S1+1S3-1S1+S2-1S2+S3 (8)[xv] where r has also been expressed in terms of the contact separations (figure 17). This can be rearranged in order to calculate the value of the resistivity of material being measured. The probe was once again inserted into the cryostat and the cryostat was cooled as detailed in section II.I. Once the sample had reached a temperature equal to that of the boiling point of liquid nitrogen a LabView program was left to run which recorded the resistance of the sample and its corresponding temperature. The program used to do this can be seen in appendix 2. Although a temperature increase function was built into the program, the cryostat was left to warm up naturally for the same reason used when calibrating the platinum thermometer. The set up for this can be seen below in figure 18. Figure 18. Schematic for the resistivity experiment. Vacuum pumps and pressure gauges have been omitted as well as the heater on the ITC as none of the bear any real relevance to the experiment. Data cables are shown in red, Pt100 in blue and sample in grey. This was repeated for each sample of fabricated YBCO at least twice and their temperature dependant resistivity profiles can be seen in section III.II III.II Resistivity Results, Analysis and Interpretations The resistance profile of the sample from the first batch was measured twice and these profiles can be seen in figure 19. Unfortunately it was not possible on this occasion to measure the four point probe contact separations on this first sample before it was removed and so these profiles could not be adjusted to those of resistivity using equation 8. However, as this transformation is simply a stretch in the y-axis, it does not change the behaviour of the transition or the value of the transition temperature obtained from the profile. It can be seen in figure 19 that although the first profile cuts out at approximately a temperature of 190 Kelvin, both profiles follow virtually the same path until that point. The first profile cuts out early due to data points being taken once every second causing the program to fail and shut down. The number of data points was then cut to one every three seconds for subsequent experiments. With measurements being taken automatically by computer (and with the Keithley multimeters ability to measure currents and voltages to 7 significant figures) the errors on the resistance were negligible (Ãâà ±0.003% of the value of the resistance) and so can not be seen in figure 19. The same is true of the errors on the temperature. Assuming that equation 7 is correct then with a Ãâà ±0.003% error on any calculated resistance, the temperature of the sample space should only have an error of Ãâà ±0.04K. Had each of the samples been perfectly pure their profiles would have a very sharp transition between the states and the transition temperature would be very clear. However as a result of the broadening of this transition due to the impurity of the samples a temperature could not be clearly defined. Had powerful enough graphing software been to hand and were the profile able to be fitted to any know curve on this software, the most reliable way to find the transition temperature would have been to plot the first derivative of resistivity with respect to temperature and then determine its maximum (corresponding to the point of inflection within the transition). This not being the case the temperature of the transition was approximated to be the temperature at the half way point in the drop between the two states. To ascertain at which points on the profile the change in state began and ended, separate lines of linear regression were fitted to the linear data in both the normal state and the superconducting state. These two lines of regression were extended closer and closer to the transition from either side until the adjusted R2 value of the lines of best fit was 0.999, which indicated an excellent linear fit. It was found upon inspection that the mid-point of the transition could be defined in two different ways; the mid point in resistivity and the mid point in temperature (the mid-point in resistivity obviously corresponding to slightly a different temperature than that found at the mid point of the temperature). This was due to a slight skew in the transition in the profile and so in order to clearly define the superconducting transition temperature a clearer approximation from the one stated before had to be made. It was therefore approximated that the temperature corresponding to the mid point in resistivity should be averaged with the mid point in temperature on the x-axis and the error be the temperature either side of this average value which either previous mid value lay. This can be seen more clearly in figure 20. Figure 20: Shows the method used to calculate the superconducting transition temperature using an expanded view of the first profile in figure 19. Lines of linear regression are shown in black either side of the area in which the transition occurs (in yellow). Both temperatures can be seen highlighted by dashed lines. By the use of this method it was determined that the transition temperatures for both of the profiles in figure 19 were 87.6(Ãâà ±0.9)K and 86.0(Ãâà ±0.4)K for the first and second profiles respectively. Although these do not agree with each other (within the confines set by the errors) an average was taken and found to be 86.8(Ãâà ±0.8)K. The purity indicator was also calculated for each profil
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