Sunday, January 26, 2020

CAD for Electromagnetic Devices Laboratory Exercise

CAD for Electromagnetic Devices Laboratory Exercise An introduction to numerical modelling techniques for electromagnetic problems using finite element analysis Contents 2. Introduction 3. Simulation Results 3.1 Electric Potential 3.2 Magnetic Flux Density 3.3 Magnetic Flux Density For Single Conductor 3.4 Finite Difference vs Finite Element 3.5 Comb Drive Micro Actuator 3.6 Magnetic Circuit 4. Discussion Finite element analysis (FEA) is the modelling of products and systems in a virtual environment, for the purpose of solving potential (or existing) structural or performance issues. (1) FEA is the practical application of the finite element method (FEM), a numerical technique for approximating solutions to boundary value problems for partial differential equations (2) which cannot be solved analytically. This method works by separating a large system into smaller parts called finite elements, known as discretization (3). The simple equations governing these finite elements are accumulated to form an overall system of equations for the problem, which FEM uses to approximate a solution. Computational Electromagnetics is the process of modelling the interaction of electromagnetic fields with physical objects and the environment. (4) The electromagnetic analysis that this involves is based on solving Maxwells equations subject to given boundary conditions. Maxwells equations can be expressed in general differential form and therefore the solutions to electromagnetic problems governed by these equations can be modelled and solved using FEM. (5) The electromagnetic problems outlined in this report have been modelled and approximated in two-dimensional space using the finite element program pdetool in MatLab. This is done through the use of linear triangular elements. 3.1 Electric Potential The aim of this experiment was to model the electric potential between two circular metallic conductors of radius 30 cm and centre distance 120cm. The left and right conductors were subject to Dirichlet boundary conditions and given potentials of 1 and -1 respectively. The enclosed area was modelled using the Neumann boundary condition (6) and the current source set to 0. The following model was observed: The purple to blue shading demonstrates the varying electric potential across the model, with V = 0 at the midpoint of the two conductors as anticipated due to the equation†¦ The electric field is visualised through the red arrows, confirming the expectation that the current would flow from the positively charged conductor to the negatively charged conductor. 3.2 Magnetic Flux Density This experiment aimed to model the magnetic field between two cylindrical, current-carrying conductors of radius 5cm and centre distance of 60cm. The magnetic permeability of both conductors was set to and the current density set to 1 and -1 respectively. The enclosed area was modelled using Dirichlet boundary conditions with magnetic potential set to 0, and the magnetic potential and current density set to and 0 correspondingly. The following model was observed: The red arrows show the direction of the magnetic field at certain points, while the shading demonstrates the magnitude of the magnetic flux density, clearly highlighting that the strength of magnetic flux decreases with distance away from the conductors. The current in each conductor is given by the equation , where J is the current density and A is the cross sectional area of the conductor. Using this equation yields a current of 7.85mA for the left conductor and -7.85mA for the right conductor. 3.3 Magnetic Flux Density For Single Conductor The experiment from 3.2 was then replicated using a single, circular, current-carrying conductor of radius 0.2cm. The boundary conditions for the enclosed area remained the same while, for the conductor, magnetic permeability was set to and current density to 1. The following model was observed: The magnetic flux density was then measured from the FEM model for a number of distances and compared with results calculated from theory; this comparison can be found in table 1 below. 3.4 Finite Difference vs Finite Element For this electrostatic model, a 16cm x 12cm square was plotted to represent four electric diodes of differing electric potential, shown in figure 4. The dielectric permittivity of the electric diodes was set to 1 and the electric potential and electric field for the system was modelled as shown below: The variation of electric field between the positive and negative diodes is represented through the shading and the electric field lines are shown in black. Values for the electric potential at particular geometric coordinates were then measured from the FEM model and compared against the results calculated from FDM; this comparison can be found in table 2. 3.5 Comb Drive Micro Actuator This experiment aimed to model the electric field distribution of a voltage controlled, comb-drive, electrostatic micro-actuator, consisting of a movable comb and a fixed comb, with the latter containing four fingers. The dimensions of the comb were specified as follows: w=1, d=1, dl=0.6 and Lc=3 (all figures are in mm) and explained through figure 6: The movable comb was given a potential of 5V and the fixed comb a potential of -5V to simulate a 10V applied voltage. The electric potential of the enclosed area was set to 0 and the space charge density to 0 as well. The following model, demonstrating electric field distribution, was observed: 3.6 Magnetic Circuit A model for an electromagnet was created as shown in figure 8 below: The magnetic permeability of the iron was set to 500 and current density 0. The coil was represented in the model by two rectangles either side of where the coil appears in figure 6, one with positive and one with negative current density. Given that the current in the coil is 10 A-turns, the current density is given by the equation, where A is equal to the area of the approximated coil. The magnetic permeability of both the coil and the enclosed area were set to and models for the magnetic flux density and magnetic field were achieved. These are shown below: The experiment was then altered to model the effects of the coil if the material of the magnet was plastic, with a relative permeability of 1, and therefore the magnetic permeability of the magnet was set to . All the other values remained constant. The magnetic flux density and magnetic field were then found and are shown below:

Saturday, January 18, 2020

“The Lemon Tree” Essay

Film Viewing Assignment The film that I watched is called â€Å"The Lemon Tree† directed by Eran Riklis. The actors spoke in both Arabic and Hebrew, as its plot involved both Palestinians and Israelis. The film took place in the West Bank, Palestine. A middle-aged Palestinian widow named Salma Zidane lives on a property that belongs to her great grandparents. On this property is a field of lemon trees planted by her grandparents themselves when they were alive. This field provides her with a steady source of income and, I believe, a hidden sense of pride.In the film, she gets new neighbors living right across from her. They live exactly on the green line border between Israel and the West Bank. To her disadvantage, her new neighbor is the Israeli Defense Minister and his family. Not to my surprise however, the Defense Minister declares Salma’s field of trees as a threat to the Minister’s safety and quickly tries to initiate an order to uproot them. So, in turn, S alma tries to fight this order. She calls upon Ziad Daud, a young lawyer, to help her save her trees.What greatly interested me, however, was the invisible bond that had developed between Salma and the Minister’s wife, Mira Navon. This woman was portrayed as unhappy with her life in her new house and feels bad for Salma and her situation. They come from two separate worlds, yet they share similar feelings as individuals, rather than as Palestinians and Israelis. This was something I had hoped all viewers would notice and take into regard. Most of the time, the Palestinian-Israeli conflict is never viewed as neutral.Both peoples are criticized, and in my belief, the Palestinians are targeted more harshly than the Israelis. Yet my point is that it is refreshing to see representatives from both parties seen as individuals who struggle with everyday problems, rather than entire minorities battling this ongoing situation. For the most part, this film did a great job of capturing l ife in Palestine and some Israel from a physical standpoint. It captured everything that I, as a Palestinian, am used to seeing.The entire plot was unique yet very accurate in its depiction of what the Israelis will do to sabotage the people and land that mark the very existence of a once peaceful Palestinian state. However, I did not appreciate the romance that occurred between Salma and her lawyer, Ziad. This is completely inaccurate of the Palestinian mentality. Since this was an independent film about a conflict that not many people are completely aware of, viewers will subconsciously or even consciously get a solid idea as to how the Palestinians behave from it.As I know them, Palestinians are very respectful people. They respect themselves and as far as being men and women, they know where they stand. Though a person can argue that Salma felt vulnerable due to the situation that she was in and the fact that she had no man in her life to really comfort her, one has to understan d that there are so many Palestinian families that have lost their husbands/wives/ siblings/kids and they do not invoke shame onto whatever is left of their family through romantic affairs.Yes, she was depressed, and yes she is alone, but the typical Palestinian woman will look to God, not another man, to help her get through her problems. Granted, this film does not depict the entire minority as a whole, but it is implied that Salma represents them. So being the representation of the Palestinians, she is scandalous and insecure. Meanwhile, the Israeli family is very clean and well-kept. They are shown as happy and celebrative at their house-warming party; While Salma and the visitors that we see are quite depressing.In class, we have very briefly discussed the Palestinian-Israeli conflict. It is an extremely controversial and sensitive issue, for we couldn’t even make it through twenty minutes on the subject without having a very defensive intruder raise his voice in the cla ss. Though we have learned that both the Jews and the Arabs have inhabited this land since a time that anthropologists cannot even track, it is still appalling to me how such people can be so inhumane. There is so much evidence, when searched for correctly and accurately, that the Palestinian existence is weakening.Cities are being attacked, villages demolished or evacuated, bombings, and families being destroyed are all brutal factors of the evidence. It is distinctly known through the Middle East that Israelis are destroying olive and lemon trees that are hundreds of years old. What is the point of this? To what extent is this humane and indicative of their desire for peace? Just typing about the topic enrages me. This film, produced by an Israeli, could have done a better job of portraying the Palestinians as stronger people. Though there are some nice aspects about the film, there is a lot that I would have changed.

Friday, January 10, 2020

The Key to Successful Sixth Grade Persuasive Essay Samples

The Key to Successful Sixth Grade Persuasive Essay Samples It should demonstrate the principal argument you're trying for. Drunk drivers ought to be imprisoned on the very first offense. As you can readily recognize, it all starts with a suitable argument. A seasoned professional will make an error-free assignment right away and can help you boost your grades. Partner or group work Setting aside a couple of minutes in class for students to speak with one another about their writing can be helpful. Despite the fact that you pay for homework, we provide those options free of charge. Even in the event the deadline is very tight, feel free to get hold of our managers. The Tried and True Method for Sixth Grade Persuasive Essay Samples in Step by Step Detail Likewise, it has to be logically complete and express a particular idea. There's absolutely nothing wrong with the standard school year. The word itself is a nightmare to a lot of students, particularly to those who drea d writing. You will need a strong argument if you wish to find a person to agree with your opinion when you compose an essay. The essay should provide a well-rounded comprehension of all issues before the author shows his personal conclusions and opinions. The debut of each written work ought to have a very clear thesis statement or argument. At the conclusion of reading this kind of essay, the audience should clearly understand the problem or controversy and have sufficient info to make an educated decision about the matter. Providing the reader with the fundamental breakdown of the organization of the discussion makes sure that the stream of thought is understood in the entire essay body. It doesn't matter to us, whether you're too busy on the job concentrating on a passion undertaking, or simply tired of a seemingly infinite stream of assignments. The primary purpose of this form of assignment is to provide an argumentative analysis on a specific topic. Frequently you w ill examine what other folks have already said on the exact subject and include this information utilizing paraphrasing and summarising skills, in addition to correct citations. The Tried and True Method for Sixth Grade Persuasive Essay Samples in Step by Step Detail How can you cite info in an essay How to begin and conclude a gcse english essay effectively extensive subject. however, it can be grouped into english language and literature it's important to refer back to the original question throughout where ever it could be possible. The very first sentence of each paragraph should play off the previous sentence of the prior paragraph to provide a smooth transition. Printable essay outline templates absolutely free pdf word examples writing an essay or an assignment can be an extremely difficult job especially when you've got tons. There are a couple of easy guidelines to follow as a way to be in a position to compose a very good persuasive essay. The actual men and women highly praise our essay help site. You can depend on the ideal essay help online. Professional customized essay writers for hire to make your essay from scratch. The Fight Against Sixth Grade Persuasive Essay Samples Let's install automated hand dryers at our school whenever possible. Ultimately, teachers have to be paid for all of the weeks they're working. Children should have the ability to use cellphones in school. Similarly, they would not be able to go to most summer camps. The True Meaning of Sixth Grade Persuasive Essay Samples Your list will just supply you with a headache if you don't locate a remedy to end your problems. You should have your reasons, and our primary concern is that you wind up getting an excellent grade. You see, very good arguments are the ones that make someone doubt their own beliefs. To begin with, l et's define the varieties of argument available and strategies that you may follow. Whatever They Told You About Sixth Grade Persuasive Essay Samples Is Dead Wrong...And Here's Why The very first paragraph should contain the most significant point which you plan to make about the literary work and ought to give details to support the claim. Remember you will have to produce several essential points that will support your case This ought to be a single sentence statement that's very clear and concise. It's only supposed to give it direction and draw out the key points. Be certain to have more than only one point to support your principal points. Your orders will be carried out exactly as you desire. In this instance, learning numerous sentences has lots of benefits. These words and phrases may be used. The previous sentence needs to be persuasive to the most important point and ought to show that the essay is coming to a finish.

Thursday, January 2, 2020

The Atomic Bomb Of The United States Entered Into The...

In December of 1941, the United States entered into the second World War after the Japanese attacks on Pearl Harbor. Due to these attacks and the dangerous rumors sprouting of German bomb builders, the U.S. decided to put efforts towards constructing the ultimate weapon of mass destruction: the Atomic Bomb. With billions of dollars and over 100,000 people, the Manhattan Project was founded to affirm these efforts by U.S. military and scientists. By the Manhattan Project we saw the unfortunate destruction of Japanese cities, the incredible advances in the world of science, and the threats of the cold war resulting in measures to protect against modern nuclear threats. The first origins of the Manhattan Project began as early as 1930, with physicists such as Albert Einstein, who knew of the power of the single atom. Though it wasn’t until later in the decade that German physicists were able to take those thoughts produce the first artificial nuclear reaction, and even document t he theory. Due to the publication of the theory, many people began to realize the immense power that could come from such a tremendous reaction of atoms. Then, in 1939, a letter was sent to the Franklin Roosevelt, the President of the U.S. at the time, warning of the German research developments. The letter in question was in-part sent by Albert Einstein, who along with the proceeded warnings, also advised Roosevelt to allow sufficient funding for research and development of the technology on AmericanShow MoreRelatedTruman s Choice Was A Good One989 Words   |  4 PagesOn August 6, 1945, a bomb with the force of 20,000 tons of TNT, was dropped on the Japanese city of Hiroshima. Three days later a similar bomb was dropped on the city Nagasaki. Both cities were effectively eradicated and so was there people. Six days after that, Japan surrendered, thus ending World War II. Americans supported the action of Truman, that is until they saw the images of the destructive power of the bom b. The horrific images showing the victims of radiation and of burns that are causedRead MoreEssay On The Atomic Bomb1048 Words   |  5 Pagesfirst atomic bombs were dropped in a race to end World War II. The first nuclear bomb, ‘Little Boy’, dropped over Hiroshima, Japan wiped out ninety percent of the city and immediately killed thousands. Three days later, a second atomic bomb dropped on this time over the city of Nagasaki. The bombs were created by scientists who worked in secret for years on The Manhattan Project to perfect weapons that would bring an end to the long and traumatizing fight of World War II. The use of the atomic bombRead MoreWorld War I And The Great War915 Words   |  4 PagesWorld War I, also known as the Great War, was one of the most important and traumatic war in history. It left many countries in devastation and chaos. Countries involved in the war, like Europe and America promised to prevent any other future world war because of the milli ons lives taken and the destruction caused to the world in the previous war. However, peace was not enjoyed for long and after two decades, the Second World War began from the issues that were left unresolved from the previous conflictRead MoreThe Manhattan Project1114 Words   |  5 PagesManhattan Project was to see if making an atomic bomb possible. The success of this project would forever change the world forever making it known that something this powerful can be manmade. The Manhattan Project’s success was something that had an impact on everybody involved since they helped create something with so much destructive power it could destroy a city within seconds. The University of Chicago in Illinois had a huge role with the making of the atomic bomb (The Manhattan Project, Sue Hook)Read MoreThe U.s. And Wwi1406 Words   |  6 PagesEssay The U.S. WWI The Great War, or World War I as it has become known as, changed the world in the way everyone had known it to be up until the war started. In June 1914, a nationalist from Serbia assassinated the heir to the throne of the Austro-Hungarian Empire Archduke Franz Ferdinand. The assassination was the first of many events that led to the beginning of the First World War. The war caused a great change in the American stance in the world; it caused the world power nation to turn into aRead MoreNuclear Weapons And The World War II1145 Words   |  5 PagesNuclear weapons were a crucial aspect throughout the history of the Cold War. Scientific and military development in the early 20th Century had demonstrated the potential of atoms and other properties to create large-scale nuclear weapons. The developments of the arms race within the context of World War I and World War II further led to the emergence of nuclear weapons for combat. Countries such as the United States, USSR, and Britain a lso sought to create effective nuclear weapons. SubsequentlyRead MoreThe Dropping Of The Atomic Bomb Essay1734 Words   |  7 Pagesdropping of the atomic bomb was used to save American lives; the most common excuse as to why President Harry Truman decided to drop the atomic bomb on Japan. In Major Problems in the History of World War II it has been discussed in the chapter The Atomic Bomb and the End of World War II that former President Truman recalled how he learned about the atomic bomb project as well as the public opinion on the Atomic Bomb. I believe that the solution that Truman gave when dropping the Atomic Bomb should notRead MoreExaming the Factors That Led To Dropping the Atomic Bomb on Nagasaki1314 Words   |  6 Pagesfactors that led to the United States to drop an atomic bomb on the city of Nagasaki, one can look at the event as a result of two major decisions. The first decision concerned the use of newly developed nuclear weapons in lieu of other military tech niques to secure a timely Japanese surrender. The second decision was to use several of these weapons instead of only one. Although the Truman administration displayed little hesitation or ambivalence over the decision to use atomic weapons (Walker, 51)Read MoreThe Atomic Bomb Of Hiroshima And Nagasaki981 Words   |  4 PagesIn August of 1945, The United States successfully used the Atomic bomb for the first time in the Japanese cities of Hiroshima and Nagasaki, while over 100,000 people died the greater importance of this moment would be played out in history for decades to come. (Lecture) The importance that the creation of the Atomic bomb gave the world was enough to end mankind if the wrong people were capable of finding out how to use it. It would take only a short amount of time for other countries to gain accessRead More Atomic Bomb Essay1536 Words   |  7 Pages On the morning of August 6, 1945, the first Atomic Bomb in history was dropped on the Japanese city of Hiroshima. Three days later, a second bomb was dropped on Nagasaki. Soon after, on August 14, 1945, the Japanese abruptly surrendered, abandoning their ancient customs regarding honor in war. The fact that only two bombs were able to bring an entire country to its knees is a true testament to the awesome power they held. There is nothing in modern warfare that can compete with the devastating