1 IN2009: Language Processors Coursework Part 3: The Interpreter Introduction This is the 3rd and final part of the coursework. In the second part of the coursework you created a parser for the Moopl grammar which, given a syntactically correct Moopl program as input, builds an AST representation of the program. In Part 3 you will develop an interpreter which executes Moopl programs by visiting their AST representations. For this part of the coursework we provide functional code (with limitations, see below) for parsing, building a symbol table, type checking and variable allocation. Marks This part of the coursework is worth 12 of the 30 coursework marks for the Language Processors module. This part of the coursework is marked out of 12. Submission deadline This part of the coursework should be handed in before 5pm on Sunday 9th April 2017. In line with school policy, late submissions will be awarded no marks. Return & Feedback Marks and feedback will be available as soon as possible, certainly on or before Wed 3rd May 2017. Plagiarism If you copy the work of others (either that of fellow students or of a third party), with or without their permission, you will score no marks and further disciplinary action will be taken against you. Group working You will be working in the same groups as for the previous parts of the coursework except where group changes have already been approved. Submission: Submit a zip archive (not a rar file) of all your source code (the src folder of your project). We do not want the other parts of your NetBeans project, only the source code. Note 1: Submissions which do not compile will get zero marks. Note 2: You must not change the names or types of any of the existing packages, classes or public methods. 2 Getting started Download either moopl-interp.zip or moopl-interp.tgz from Moodle and extract all files. Key contents to be aware of: • A fully implemented Moopl parser (also implements a parser for the interpreter command language; see below). • A partially implemented Moopl type checker. • Test harnesses for the type checker and interpreter. • A directory of a few example Moopl programs (see Testing below). • Folder interp containing prototype interpreter code. The type-checker is only partially implemented but a more complete implementation will be provided following Session 6. That version is still not fully complete because it doesn’t support inheritance. Part d) below asks you to remove this restriction. The VarAllocator visitor in the interp package uses a simple implementation which only works for methods in which all parameter and local variable names are different. Part e) below asks you to remove this restriction. The three parts below should be attempted in sequence. When you have completed one part you should make a back-up copy of the work and keep it safe, in case you break it in your attempt at the next part. Be sure to test old functionality as well as new (regression testing). We will not assess multiple versions so, if your attempt at part d) or e) breaks previously working code, you may gain a better mark by submitting the earlier version for assessment. c) [8 marks] The Basic Interpreter: complete the implementation of the Interpreter visitor in the interp package. d) [2 marks] Inheritance: extend the type-checker, variable allocator and interpreter to support inheritance. e) [2 marks] Variable Allocation: extend the variable allocator to fully support blockstructure and lexical scoping, removing the requirement that all parameter and local variable names are different. Aim to minimise the number of local variable slots allocated in a stack frame. Note: variable and parameter names declared at the same scope level are still required to be different from each other (a method cannot have two different parameters called x, for example) and this is enforced by the existing typechecking code. But variables declared in different blocks (even when nested) can have the same name. Exceptions Your interpreter will only ever be run on Moopl code which is type-correct (and free from uninitialised local variables). But it is still possible that the Moopl code contains logical errors which may cause runtime errors (such as null-reference or array-bound errors). Your interpreter should throw a MooplRunTimeException with an appropriate error message in these cases. The only kind of exception your interpreter should ever throw is a MooplRunTimeException. 3 Testing The examples folder does not contain a comprehensive test-suite. You need to invent and run your own tests. The document Moopl compared with Java gives a concise summary of how Moopl programs are supposed to behave. You can (and should) also compare the behaviour of your interpreter with that of the online tool: https://smcse.city.ac.uk/student/sj353/langproc/Moopl.html (Note: the online tool checks for uninitialised local variables. Your implementation is not expected to do this.) To test your work, run the top-level Interpret harness, providing the name of a Moopl source file as a command-line argument. When run on a type-correct Moopl source file, Interpret will pretty-print the Moopl program then display a command prompt (>) at which you can enter one of the following commands: :quit This will quit the interpreter. :call main() This will call the top-level proc main, interpreted in the context defined by the Moopl program. (Any top-level proc can be called this way). :eval Exp ; This will evaluate expression Exp, interpreted in the context defined by the Moopl program, and print the result. Note the required terminating semi-colon. Testing your Expression visitors To unit-test your Exp visit methods, run the top-level Interpret harness on a complete Moopl program (though it can be trivial) and use the :eval command. For example, to test your visit methods for the Boolean-literals (ExpTrue and ExpFalse), you would enter the commands > :eval true ; > :eval false ; which should output 1 and 0, respectively. For the most basic cases, the Moopl program is essentially irrelevant (a single top-level proc with empty body may be sufficient). For other cases you will need to write programs containing class definitions (in order, for example, to test object creation and method call). Testing your Statement visitors To unit-test your Stm visit methods, write very simple Moopl programs, each with a top-level proc main() containing just a few lines of code. Run the top-level Interpret harness on these simple programs and enter the command > :call main() You will find a few examples to get you started in the folder examples/unittests. As for the Exp tests, simple cases can be tested using Moopl programs with just a main proc but for the more complex tests you will need to write Moopl programs containing class definitions. 4 Grading criteria Solutions will be graded according to their functional correctness, and the elegance of their implementation. Below are criteria that guide the award of marks. 70 – 100 [1st class] Work that meets all the requirements in full, constructed and presented to a professional standard. Showing evidence of independent reading, thinking and analysis. 60 – 69 [2:1] Work that makes a good attempt to address the requirements, realising all to some extent and most well. Well-structured and well presented. 50 – 59 [2:2] Work that attempts to address requirements realising all to some extent and some well but perhaps also including irrelevant or underdeveloped material. Structure and presentation may not always be clear. 40 – 49 [3rd class] Work that attempts to address the requirements but only realises them to some extent and may not include important elements or be completely accurate. Structure and presentation may lack clarity. 0 – 39 [fail] Unsatisfactory work that does not adequately address the requirements. Structure and presentation may be confused or incoherent.

1 IN2009: Language Processors Coursework Part 3: The Interpreter Introduction This is the 3rd and final part of the coursework. In the second part of the coursework you created a parser for the Moopl grammar which, given a syntactically correct Moopl program as input, builds an AST representation of the program. In Part 3 you will develop an interpreter which executes Moopl programs by visiting their AST representations. For this part of the coursework we provide functional code (with limitations, see below) for parsing, building a symbol table, type checking and variable allocation. Marks This part of the coursework is worth 12 of the 30 coursework marks for the Language Processors module. This part of the coursework is marked out of 12. Submission deadline This part of the coursework should be handed in before 5pm on Sunday 9th April 2017. In line with school policy, late submissions will be awarded no marks. Return & Feedback Marks and feedback will be available as soon as possible, certainly on or before Wed 3rd May 2017. Plagiarism If you copy the work of others (either that of fellow students or of a third party), with or without their permission, you will score no marks and further disciplinary action will be taken against you. Group working You will be working in the same groups as for the previous parts of the coursework except where group changes have already been approved. Submission: Submit a zip archive (not a rar file) of all your source code (the src folder of your project). We do not want the other parts of your NetBeans project, only the source code. Note 1: Submissions which do not compile will get zero marks. Note 2: You must not change the names or types of any of the existing packages, classes or public methods. 2 Getting started Download either moopl-interp.zip or moopl-interp.tgz from Moodle and extract all files. Key contents to be aware of: • A fully implemented Moopl parser (also implements a parser for the interpreter command language; see below). • A partially implemented Moopl type checker. • Test harnesses for the type checker and interpreter. • A directory of a few example Moopl programs (see Testing below). • Folder interp containing prototype interpreter code. The type-checker is only partially implemented but a more complete implementation will be provided following Session 6. That version is still not fully complete because it doesn’t support inheritance. Part d) below asks you to remove this restriction. The VarAllocator visitor in the interp package uses a simple implementation which only works for methods in which all parameter and local variable names are different. Part e) below asks you to remove this restriction. The three parts below should be attempted in sequence. When you have completed one part you should make a back-up copy of the work and keep it safe, in case you break it in your attempt at the next part. Be sure to test old functionality as well as new (regression testing). We will not assess multiple versions so, if your attempt at part d) or e) breaks previously working code, you may gain a better mark by submitting the earlier version for assessment. c) [8 marks] The Basic Interpreter: complete the implementation of the Interpreter visitor in the interp package. d) [2 marks] Inheritance: extend the type-checker, variable allocator and interpreter to support inheritance. e) [2 marks] Variable Allocation: extend the variable allocator to fully support blockstructure and lexical scoping, removing the requirement that all parameter and local variable names are different. Aim to minimise the number of local variable slots allocated in a stack frame. Note: variable and parameter names declared at the same scope level are still required to be different from each other (a method cannot have two different parameters called x, for example) and this is enforced by the existing typechecking code. But variables declared in different blocks (even when nested) can have the same name. Exceptions Your interpreter will only ever be run on Moopl code which is type-correct (and free from uninitialised local variables). But it is still possible that the Moopl code contains logical errors which may cause runtime errors (such as null-reference or array-bound errors). Your interpreter should throw a MooplRunTimeException with an appropriate error message in these cases. The only kind of exception your interpreter should ever throw is a MooplRunTimeException. 3 Testing The examples folder does not contain a comprehensive test-suite. You need to invent and run your own tests. The document Moopl compared with Java gives a concise summary of how Moopl programs are supposed to behave. You can (and should) also compare the behaviour of your interpreter with that of the online tool: https://smcse.city.ac.uk/student/sj353/langproc/Moopl.html (Note: the online tool checks for uninitialised local variables. Your implementation is not expected to do this.) To test your work, run the top-level Interpret harness, providing the name of a Moopl source file as a command-line argument. When run on a type-correct Moopl source file, Interpret will pretty-print the Moopl program then display a command prompt (>) at which you can enter one of the following commands: :quit This will quit the interpreter. :call main() This will call the top-level proc main, interpreted in the context defined by the Moopl program. (Any top-level proc can be called this way). :eval Exp ; This will evaluate expression Exp, interpreted in the context defined by the Moopl program, and print the result. Note the required terminating semi-colon. Testing your Expression visitors To unit-test your Exp visit methods, run the top-level Interpret harness on a complete Moopl program (though it can be trivial) and use the :eval command. For example, to test your visit methods for the Boolean-literals (ExpTrue and ExpFalse), you would enter the commands > :eval true ; > :eval false ; which should output 1 and 0, respectively. For the most basic cases, the Moopl program is essentially irrelevant (a single top-level proc with empty body may be sufficient). For other cases you will need to write programs containing class definitions (in order, for example, to test object creation and method call). Testing your Statement visitors To unit-test your Stm visit methods, write very simple Moopl programs, each with a top-level proc main() containing just a few lines of code. Run the top-level Interpret harness on these simple programs and enter the command > :call main() You will find a few examples to get you started in the folder examples/unittests. As for the Exp tests, simple cases can be tested using Moopl programs with just a main proc but for the more complex tests you will need to write Moopl programs containing class definitions. 4 Grading criteria Solutions will be graded according to their functional correctness, and the elegance of their implementation. Below are criteria that guide the award of marks. 70 – 100 [1st class] Work that meets all the requirements in full, constructed and presented to a professional standard. Showing evidence of independent reading, thinking and analysis. 60 – 69 [2:1] Work that makes a good attempt to address the requirements, realising all to some extent and most well. Well-structured and well presented. 50 – 59 [2:2] Work that attempts to address requirements realising all to some extent and some well but perhaps also including irrelevant or underdeveloped material. Structure and presentation may not always be clear. 40 – 49 [3rd class] Work that attempts to address the requirements but only realises them to some extent and may not include important elements or be completely accurate. Structure and presentation may lack clarity. 0 – 39 [fail] Unsatisfactory work that does not adequately address the requirements. Structure and presentation may be confused or incoherent.

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Sex, Gender, and Popular Culture Spring 2015 Look through popular magazines, and see if you can find advertisements that objectify women in order to sell a product. Alternately, you may use an advertisement on television (but make sure to provide a link to the ad so I can see it!). Study these images then write a paper about objectification that deals with all or some of the following: • What effect(s), if any, do you think the objectification of women’s bodies has on our culture? • Jean Kilbourne states “turning a human being into a thing is almost always the first step toward justifying violence against that person.” What do you think she means by this? Do you agree with her reasoning? Why or why not? • Some people would argue that depicting a woman’s body as an object is a form of art. What is your opinion of this point of view? Explain your reasoning. • Why do you think that women are objectified more often than men are? • How does sexualization and objectification play out differently across racial lines? • Kilbourne explains that the consequences of being objectified are different – and more serious – for women than for men. Do you agree? How is the world different for women than it is for men? How do objectified images of women interact with those in our culture differently from the way images of men do? Why is it important to look at images in the context of the culture? • What is the difference between sexual objectification and sexual subjectification? (Ros Gill ) • How do ads construct violent white masculinity and how does that vision of masculinity hurt both men and women? Throughout your written analysis, be sure to make clear and specific reference to the images you selected, and please submit these images with your paper. Make sure you engage with and reference to at least 4 of the following authors: Kilbourne, Bordo, Hunter & Soto, Rose, Durham, Gill, Katz, Schuchardt, Ono and Buescher. Guidelines:  Keep your content focused on structural, systemic, institutional factors rather than the individual: BE ANALYTICAL NOT ANECDOTAL.  Avoid using the first person or including personal stories/reactions. You must make sure to actively engage with your readings: these essays need to be informed and framed by the theoretical material you have been reading this semester.  Keep within the 4-6 page limit; use 12-point font, double spacing and 1-inch margins.  Use formal writing conventions (introduction/thesis statement, body, conclusion) and correct grammar. Resources may be cited within the text of your paper, i.e. (Walters, 2013).

Sex, Gender, and Popular Culture Spring 2015 Look through popular magazines, and see if you can find advertisements that objectify women in order to sell a product. Alternately, you may use an advertisement on television (but make sure to provide a link to the ad so I can see it!). Study these images then write a paper about objectification that deals with all or some of the following: • What effect(s), if any, do you think the objectification of women’s bodies has on our culture? • Jean Kilbourne states “turning a human being into a thing is almost always the first step toward justifying violence against that person.” What do you think she means by this? Do you agree with her reasoning? Why or why not? • Some people would argue that depicting a woman’s body as an object is a form of art. What is your opinion of this point of view? Explain your reasoning. • Why do you think that women are objectified more often than men are? • How does sexualization and objectification play out differently across racial lines? • Kilbourne explains that the consequences of being objectified are different – and more serious – for women than for men. Do you agree? How is the world different for women than it is for men? How do objectified images of women interact with those in our culture differently from the way images of men do? Why is it important to look at images in the context of the culture? • What is the difference between sexual objectification and sexual subjectification? (Ros Gill ) • How do ads construct violent white masculinity and how does that vision of masculinity hurt both men and women? Throughout your written analysis, be sure to make clear and specific reference to the images you selected, and please submit these images with your paper. Make sure you engage with and reference to at least 4 of the following authors: Kilbourne, Bordo, Hunter & Soto, Rose, Durham, Gill, Katz, Schuchardt, Ono and Buescher. Guidelines:  Keep your content focused on structural, systemic, institutional factors rather than the individual: BE ANALYTICAL NOT ANECDOTAL.  Avoid using the first person or including personal stories/reactions. You must make sure to actively engage with your readings: these essays need to be informed and framed by the theoretical material you have been reading this semester.  Keep within the 4-6 page limit; use 12-point font, double spacing and 1-inch margins.  Use formal writing conventions (introduction/thesis statement, body, conclusion) and correct grammar. Resources may be cited within the text of your paper, i.e. (Walters, 2013).

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Essay list

Essay list

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AUCS 340: Ethics in the Professions Individual Written Assignment #1 Medical Ethics: Historical names, dates and ethical theories assignment As you read chapters 1 and 2 in the “Ethics and Basic Law for Medical Imaging Professionals” textbook you will be responsible for identifying and explaining each of the following items from the list below. You will respond in paragraph format with correct spelling and grammar expected for each paragraph. Feel free to have more than one paragraph for each item, although in most instances a single paragraph response is sufficient. If you reference material in addition to what is available in the textbook it must be appropriately cited in your work using either APA or MLA including a references cited page. The use of Wikipedia.com is not a recognized peer reviewed source so please do not use that as a reference. When responding about individuals it is necessary to indicate a year or time period that the person discussed/developed their particular ethical theory so that you can look at and appreciate the historical background to the development of ethical theories and decision making. Respond to the following sixteen items. (They are in random order from your reading) 1. Francis Bacon 2. Isaac Newton 3. Prima Facie Duties – Why do they exist? LIST AND DEFINE ALL TERMS 4. Hippocrates 5. W.D. Ross – what do the initials stand for in his name and what was his contribution to the study of ethics? 6. Microallocation – define the term and provide an example separate from the book example (You should develop your own example rather than looking for an online example; this will use your critical thinking skills. Consider an application to your own profession as microallocation is NOT limited to the medical field.) 7. Deontology – Discuss at length the basic types/concepts of this theory 8. Thomas Aquinas – 1) Discuss the ethical theory developed by Aquinas, 2) his religious affiliation, 3) why that was so important to his ethical premise and 4) discuss the type of ethical issues resolved to this day using this theory. 9. Macroallocation – define and provide an example separate from the book example (You should develop your own example rather than looking for an online example; this will use your critical thinking skills. Consider an application to your own profession as macroallocation is NOT limited to the medical field.) 10. David Hume 11. Rodericus Castro 12. Plato and “The Republic” 13. Pythagoras 14. Teleology – Discuss at length the basic types/concepts of this theory 15. Core Values – Why do they exist? LIST AND DEFINE ALL TERMS 16. Develop a timeline that reflects the ethical theories as developed by the INDIVIDUALS presented in this assignment. This assignment is due Saturday March 14th at NOON and is graded as a homework assignment. Grading: Paragraph Formation = 20% of grade (bulleted lists are acceptable for some answers) Answers inclusive of major material for answer = 40% of grade Creation of Timeline = 10% of grade Sentence structure, application of correct spelling and grammar = 20% of grade References (if utilized) = 10% of grade; references should be submitted on a separate references cited page. Otherwise this 10% of the assignment grade will be considered under the sentence structure component for 30% of the grade. It is expected that the finished assignment will be two – three pages of text, double spaced, using 12 font and standard page margins.

AUCS 340: Ethics in the Professions Individual Written Assignment #1 Medical Ethics: Historical names, dates and ethical theories assignment As you read chapters 1 and 2 in the “Ethics and Basic Law for Medical Imaging Professionals” textbook you will be responsible for identifying and explaining each of the following items from the list below. You will respond in paragraph format with correct spelling and grammar expected for each paragraph. Feel free to have more than one paragraph for each item, although in most instances a single paragraph response is sufficient. If you reference material in addition to what is available in the textbook it must be appropriately cited in your work using either APA or MLA including a references cited page. The use of Wikipedia.com is not a recognized peer reviewed source so please do not use that as a reference. When responding about individuals it is necessary to indicate a year or time period that the person discussed/developed their particular ethical theory so that you can look at and appreciate the historical background to the development of ethical theories and decision making. Respond to the following sixteen items. (They are in random order from your reading) 1. Francis Bacon 2. Isaac Newton 3. Prima Facie Duties – Why do they exist? LIST AND DEFINE ALL TERMS 4. Hippocrates 5. W.D. Ross – what do the initials stand for in his name and what was his contribution to the study of ethics? 6. Microallocation – define the term and provide an example separate from the book example (You should develop your own example rather than looking for an online example; this will use your critical thinking skills. Consider an application to your own profession as microallocation is NOT limited to the medical field.) 7. Deontology – Discuss at length the basic types/concepts of this theory 8. Thomas Aquinas – 1) Discuss the ethical theory developed by Aquinas, 2) his religious affiliation, 3) why that was so important to his ethical premise and 4) discuss the type of ethical issues resolved to this day using this theory. 9. Macroallocation – define and provide an example separate from the book example (You should develop your own example rather than looking for an online example; this will use your critical thinking skills. Consider an application to your own profession as macroallocation is NOT limited to the medical field.) 10. David Hume 11. Rodericus Castro 12. Plato and “The Republic” 13. Pythagoras 14. Teleology – Discuss at length the basic types/concepts of this theory 15. Core Values – Why do they exist? LIST AND DEFINE ALL TERMS 16. Develop a timeline that reflects the ethical theories as developed by the INDIVIDUALS presented in this assignment. This assignment is due Saturday March 14th at NOON and is graded as a homework assignment. Grading: Paragraph Formation = 20% of grade (bulleted lists are acceptable for some answers) Answers inclusive of major material for answer = 40% of grade Creation of Timeline = 10% of grade Sentence structure, application of correct spelling and grammar = 20% of grade References (if utilized) = 10% of grade; references should be submitted on a separate references cited page. Otherwise this 10% of the assignment grade will be considered under the sentence structure component for 30% of the grade. It is expected that the finished assignment will be two – three pages of text, double spaced, using 12 font and standard page margins.

Francis Bacon was a 16th century ethical theorist who was … Read More...
Explain the relationship between the physical environments and the types of cultures and societies that the various indigenous peoples developed — be sure to use specific examples. Why do you think some Native American societies formed large-scale societies, while most did not? What do the Native American stories in the History 10 Readings reveal about what they valued? (Be sure to refer to the documents by name in your work and explain how the story reveals what they valued. For example, you could say, “In the reading about the Creation of the World, the Zuni saw the importance of both men and women in the roles that Sky-father and Earth-mother play together in determining how their children will find their way in the world by . . . . ” And then use a relevant quote from the story to support your point. ) Unit 3: Unit 1.1: Native Americans – Unit 1 Threaded Discussion 1 You have now read and examined a variety of Native American cultures. Europeans referred to them as “savage” or “uncivilized.” But do cultural differences, shaped by the environments in which people found themselves, make a peoples savage or uncivilized? Unit 1 — Threaded Discussion 1

Explain the relationship between the physical environments and the types of cultures and societies that the various indigenous peoples developed — be sure to use specific examples. Why do you think some Native American societies formed large-scale societies, while most did not? What do the Native American stories in the History 10 Readings reveal about what they valued? (Be sure to refer to the documents by name in your work and explain how the story reveals what they valued. For example, you could say, “In the reading about the Creation of the World, the Zuni saw the importance of both men and women in the roles that Sky-father and Earth-mother play together in determining how their children will find their way in the world by . . . . ” And then use a relevant quote from the story to support your point. ) Unit 3: Unit 1.1: Native Americans – Unit 1 Threaded Discussion 1 You have now read and examined a variety of Native American cultures. Europeans referred to them as “savage” or “uncivilized.” But do cultural differences, shaped by the environments in which people found themselves, make a peoples savage or uncivilized? Unit 1 — Threaded Discussion 1

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ELEC 2000 Semiconductor Devices Homework #1 Choose the answer that best completes the statement or answers the question. (1) Assume the valence electron is removed from a copper atom. The net charge of the atom becomes a. 0 b. +1 c. -1 d. +4 (2) The valence electron of a copper atom experiences what kind of attraction toward the nucleus? a. None b. Weak c. Strong d. Impossible to say (3) How many valence electrons does a silicon atom have? a. 0 b. 1 c. 2 d. 4 (4) Silicon atoms combine into an orderly pattern called a a. Covalent bond b. Crystal c. Semiconductor d. Valence orbit (5) An intrinsic semiconductor has some holes in it at room temperature. What causes these holes? a. Doping b. Free electrons c. Thermal energy d. Valence electrons (6) The merging of a free electron and a hole is called a. Covalent bonding b. Lifetime c. Recombination d. Thermal energy (7) At room temperature an intrinsic silicon crystal acts approximately a. A Battery b. A conductor c. An insulator d. Copper wire (8) The amount of time between the creation of a hole and its disappearance is called a. Doping b. Lifetime c. Recombination d. Valence (9) A conductor has how many type of flow? a. 1 b. 2 c. 3 d. 4 (10) A semiconductor has how many types of flow? a. 1 b. 2 c. 3 d. 4 (11) For semiconductor material, its valence orbit is saturated when it contains a. 1 electron b. Equal (+) and (-) ions c. 4 electrons d. 8 electrons (12) In an intrinsic semiconductor, the number of holes a. Equal the number of free electrons b. Is greater than the number of free electrons c. Is less than the number of free electrons d. None of the above (13) The number of free electrons and holes in an intrinsic semiconductor decreases when the temperature a. Decreases b. Increases c. Stays the same d. None of the above (14) The flow of valence electrons to the right means that holes are flowing to the a. Left b. Right c. Either way d. None of the above (15) Holes act like a. Atoms b. Crystals c. Negative charges d. Positive charges (16) An donor atom has how many valence electrons? a. 1 b. 3 c. 4 d. 5 (17) If you wanted to produce a p-type semiconductor, which of these would you use? a. Acceptor atoms b. Donor atoms c. Pentavalent impurity d. Silicon (18) Electrons are the minority carriers in which type of semiconductor? a. Extrinsic b. Intrinsic c. n-Type d. p-type (19) Silver is the best conductor. How many valence electrons do you think it has? a. 1 b. 4 c. 18 d. 29 (20) Which of the following describes an n-type semiconductor? a. Neutral b. Positively charged c. Negatively charged d. has many holes (21) What is the barrier potential of a silicon diode a room temperature? a. 0.3 V b. 0.7 V c. 1 V d. 2 mV per degree Celsius

ELEC 2000 Semiconductor Devices Homework #1 Choose the answer that best completes the statement or answers the question. (1) Assume the valence electron is removed from a copper atom. The net charge of the atom becomes a. 0 b. +1 c. -1 d. +4 (2) The valence electron of a copper atom experiences what kind of attraction toward the nucleus? a. None b. Weak c. Strong d. Impossible to say (3) How many valence electrons does a silicon atom have? a. 0 b. 1 c. 2 d. 4 (4) Silicon atoms combine into an orderly pattern called a a. Covalent bond b. Crystal c. Semiconductor d. Valence orbit (5) An intrinsic semiconductor has some holes in it at room temperature. What causes these holes? a. Doping b. Free electrons c. Thermal energy d. Valence electrons (6) The merging of a free electron and a hole is called a. Covalent bonding b. Lifetime c. Recombination d. Thermal energy (7) At room temperature an intrinsic silicon crystal acts approximately a. A Battery b. A conductor c. An insulator d. Copper wire (8) The amount of time between the creation of a hole and its disappearance is called a. Doping b. Lifetime c. Recombination d. Valence (9) A conductor has how many type of flow? a. 1 b. 2 c. 3 d. 4 (10) A semiconductor has how many types of flow? a. 1 b. 2 c. 3 d. 4 (11) For semiconductor material, its valence orbit is saturated when it contains a. 1 electron b. Equal (+) and (-) ions c. 4 electrons d. 8 electrons (12) In an intrinsic semiconductor, the number of holes a. Equal the number of free electrons b. Is greater than the number of free electrons c. Is less than the number of free electrons d. None of the above (13) The number of free electrons and holes in an intrinsic semiconductor decreases when the temperature a. Decreases b. Increases c. Stays the same d. None of the above (14) The flow of valence electrons to the right means that holes are flowing to the a. Left b. Right c. Either way d. None of the above (15) Holes act like a. Atoms b. Crystals c. Negative charges d. Positive charges (16) An donor atom has how many valence electrons? a. 1 b. 3 c. 4 d. 5 (17) If you wanted to produce a p-type semiconductor, which of these would you use? a. Acceptor atoms b. Donor atoms c. Pentavalent impurity d. Silicon (18) Electrons are the minority carriers in which type of semiconductor? a. Extrinsic b. Intrinsic c. n-Type d. p-type (19) Silver is the best conductor. How many valence electrons do you think it has? a. 1 b. 4 c. 18 d. 29 (20) Which of the following describes an n-type semiconductor? a. Neutral b. Positively charged c. Negatively charged d. has many holes (21) What is the barrier potential of a silicon diode a room temperature? a. 0.3 V b. 0.7 V c. 1 V d. 2 mV per degree Celsius

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Course: PHYS 5426 — Quantum Statistical Physics Assignment #1 Instructor: Gennady Y. Chitov Date Assigned: January 15, 2014 Due Date: January 29, 2014 Problem 1. Prove [a; f(a†)] = @f(a†) @a† (1) [a†; f(a)] = −@f(a) @a (2) for arbitrary function f of operator which admits a series expansion. The Bose creation/ annihilation operators satisfy the standard commutation relations [a; a†] ≡ aa† − a†a = 1 (3) Hint: From Eqs.(1,2) one can figure out the corresponding commutation relations for the powers of creation/annihilation operators and then prove them by the method of mathematical induction. Note that for an arbitrary operator Aˆ: @A^n @A^ = nAˆn−1. Problem 2. In the presence of a constant external force acting on a one-dimensional oscillating particle its Hamiltonian becomes that of the so-called displaced oscillator, and the Schr¨odinger equation ˆH (q) = E (q) of the problem (cf. lecture notes) can be written in terms of dimensionless variables as ( − 1 2 d2 d2 + 1 2 2 − √ 2  ) () = ” () ; (4) where q = √ ~ m! and E = ~!”. a). Write the Schr¨odinger equation (4) in terms of the creation/annihilation operators of the harmonic oscillator ( = 0)  = √1 2 (a + a†) (5) d d = √1 2 (a − a†) (6) 1 Via a linear transformation to the new creation/annihilation operators ˜a†; ˜a preserving the bosonic commutation relations for ˜a†; ˜a map the problem (4) of the displaced oscillator onto that of a simple harmonic oscillator with new operators (˜a†; ˜a). b). Find the spectrum (eigenvalues) ” (E) of the displaced oscillator. c). Write the normalized eigenstates |n⟩ of the displaced Hamiltonian (4) via a† and the vacuum state |Θ◦⟩ of the new operators, i.e. ˜a|Θ◦⟩ = 0 (7) d). As follows from the completeness of the oscillator’s eigenstates, the vacuum state of the displaced oscillator |Θ◦⟩ can be related to the simple oscillator’s vacuum |0⟩ (i.e., a|0⟩ = 0) as |Θ◦⟩ = Ω(a†)|0⟩ (8) Find (up to a normalization factor) the operator function Ω(a†) relating two vacua. Hint: in working out Eqs.(7,8), employ Eqs.(1,2). Problem 3. Prove from the standard commutation relations ([ai; a † j ]∓ = ij , etc) that ⟨0|aiaja † ka † l |0⟩ = jkil ± ikjl (9) the sign depending on the statistics. Also calculate the vacuum expectation value ⟨0|ahaiaja † ka † l a† m |0⟩. Problem 4. In the formalism of second quantization the two-particle interaction term of the Hamiltonian for spinless fermions is given by ˆ V = 1 2 ∫ ∫ dxdy ˆ †(x) ˆ †(y)V(x; y) ˆ (y) ˆ (x) (10) For the short-ranged interaction V(x; y) = V(|x−y|) ≡ V(r) = e2 exp(−r)=r find ˆ V in the momentum representation. The field operators and the creation/annihilation operators in the momentum representation are related in the usual way, i.e., ˆ †(x) = ∫ dp (2)3 a†(p)e−ipx (11) Note that the limit  → 0 recovers the Coulomb (long-ranged) interaction V(r) = e2=r. What is the Fourier transform V(q) of the Coulomb interaction? 2 Problem 5. The matrix elements of a two-particle interaction from the previous problem can be written as ⟨k3k4|V|k1k2⟩ = (2)3(k1 + k2 − k3 − k4)V(q) (12) where q ≡ k3−k1 is the momentum transfer. Show that the diagonal part of the interaction operator ˆ V found on the previous problem in the k-representation, arises from momentum transfers q = 0 and q = k2−k1. Write down the two interaction terms and identify them as direct (q = 0) and exchange (q = k2 − k1) interactions. Draw the corresponding Feynman diagrams. Problem 6. Find the first correction to the temperature dependence of the chemical potential  of the degenerate ideal electron gas, assuming constant particle concentration ⟨N⟩=V . Express the result in terms of T and the zero-temperature chemical potential ◦. For the calculations the following formula (we set kB = 1) can be used: I ≡ ∫ ∞ 0 f(“)d” e(“−)=T + 1 = ∫  0 f(“)d” + 2 6 T2f′() + O(T4) (13) 3

Course: PHYS 5426 — Quantum Statistical Physics Assignment #1 Instructor: Gennady Y. Chitov Date Assigned: January 15, 2014 Due Date: January 29, 2014 Problem 1. Prove [a; f(a†)] = @f(a†) @a† (1) [a†; f(a)] = −@f(a) @a (2) for arbitrary function f of operator which admits a series expansion. The Bose creation/ annihilation operators satisfy the standard commutation relations [a; a†] ≡ aa† − a†a = 1 (3) Hint: From Eqs.(1,2) one can figure out the corresponding commutation relations for the powers of creation/annihilation operators and then prove them by the method of mathematical induction. Note that for an arbitrary operator Aˆ: @A^n @A^ = nAˆn−1. Problem 2. In the presence of a constant external force acting on a one-dimensional oscillating particle its Hamiltonian becomes that of the so-called displaced oscillator, and the Schr¨odinger equation ˆH (q) = E (q) of the problem (cf. lecture notes) can be written in terms of dimensionless variables as ( − 1 2 d2 d2 + 1 2 2 − √ 2  ) () = ” () ; (4) where q = √ ~ m! and E = ~!”. a). Write the Schr¨odinger equation (4) in terms of the creation/annihilation operators of the harmonic oscillator ( = 0)  = √1 2 (a + a†) (5) d d = √1 2 (a − a†) (6) 1 Via a linear transformation to the new creation/annihilation operators ˜a†; ˜a preserving the bosonic commutation relations for ˜a†; ˜a map the problem (4) of the displaced oscillator onto that of a simple harmonic oscillator with new operators (˜a†; ˜a). b). Find the spectrum (eigenvalues) ” (E) of the displaced oscillator. c). Write the normalized eigenstates |n⟩ of the displaced Hamiltonian (4) via a† and the vacuum state |Θ◦⟩ of the new operators, i.e. ˜a|Θ◦⟩ = 0 (7) d). As follows from the completeness of the oscillator’s eigenstates, the vacuum state of the displaced oscillator |Θ◦⟩ can be related to the simple oscillator’s vacuum |0⟩ (i.e., a|0⟩ = 0) as |Θ◦⟩ = Ω(a†)|0⟩ (8) Find (up to a normalization factor) the operator function Ω(a†) relating two vacua. Hint: in working out Eqs.(7,8), employ Eqs.(1,2). Problem 3. Prove from the standard commutation relations ([ai; a † j ]∓ = ij , etc) that ⟨0|aiaja † ka † l |0⟩ = jkil ± ikjl (9) the sign depending on the statistics. Also calculate the vacuum expectation value ⟨0|ahaiaja † ka † l a† m |0⟩. Problem 4. In the formalism of second quantization the two-particle interaction term of the Hamiltonian for spinless fermions is given by ˆ V = 1 2 ∫ ∫ dxdy ˆ †(x) ˆ †(y)V(x; y) ˆ (y) ˆ (x) (10) For the short-ranged interaction V(x; y) = V(|x−y|) ≡ V(r) = e2 exp(−r)=r find ˆ V in the momentum representation. The field operators and the creation/annihilation operators in the momentum representation are related in the usual way, i.e., ˆ †(x) = ∫ dp (2)3 a†(p)e−ipx (11) Note that the limit  → 0 recovers the Coulomb (long-ranged) interaction V(r) = e2=r. What is the Fourier transform V(q) of the Coulomb interaction? 2 Problem 5. The matrix elements of a two-particle interaction from the previous problem can be written as ⟨k3k4|V|k1k2⟩ = (2)3(k1 + k2 − k3 − k4)V(q) (12) where q ≡ k3−k1 is the momentum transfer. Show that the diagonal part of the interaction operator ˆ V found on the previous problem in the k-representation, arises from momentum transfers q = 0 and q = k2−k1. Write down the two interaction terms and identify them as direct (q = 0) and exchange (q = k2 − k1) interactions. Draw the corresponding Feynman diagrams. Problem 6. Find the first correction to the temperature dependence of the chemical potential  of the degenerate ideal electron gas, assuming constant particle concentration ⟨N⟩=V . Express the result in terms of T and the zero-temperature chemical potential ◦. For the calculations the following formula (we set kB = 1) can be used: I ≡ ∫ ∞ 0 f(“)d” e(“−)=T + 1 = ∫  0 f(“)d” + 2 6 T2f′() + O(T4) (13) 3

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