Writing an essay on a book
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Tuesday, August 25, 2020
Racism Revealed: Hurricane Katrina Essays -- Personal Essays Natural D
Storm Katrina struck the city of New Orleans, Louisiana on August 29th, 2005. The occasions that followed would leave the entire country in stun until this day. One of the significant subjects of conversation after this catastrophe was whether the administration's moderate response time had anything to do with the way that New Orleans is sixty-seven percent African American. As helicopters circumnavigated a no man's land that was at one time a significant vacation destination, the bigotry of the Deep South, thought to be wiped out, demonstrated it was just lethargic. A similar bigotry against African Americans that could be seen on Bourbon Street in the months preceding the tropical storm popped up again in Gretna, LA and was called attention to on live TV by rapper Kanye West. In February of 2005, Georgian Southern University understudy Levon Jones kicked the bucket of suffocation subsequent to being confined on the ground by three white bouncers at a Bourbon Street bar. Dark pioneers have accused Jones' demise for the across the board supremacist strategies in the French Quarter. Their cases depend on an overview supported by the city of New Orleans in which it was uncovered that fifteen of twenty-nine Bourbon Street bars victimized Blacks by charging fake entrance fees, gouging on drink costs and authorizing inconsistent clothing regulations. Almost five months after Jones' passing, the National Association for the Advancement of Colored People (NAACP) held a walk to fight the supremacist approaches of entrepreneurs in the French Quarter. This demonstrates bigotry against African Americans existed in New Orleans before Hurricane Katrina. After Hurricane Katrina was finished unleashing ruin on the Gulf Coast, casualties of the typhoon from New Orleans looked for food and sanctuary in the neighboring to... ...cuation Route. Nicholas Riccardi. September eighteenth, 2005 pg. 25 Report URL: http://proquest.umi.com/pqdweb?index=0&did=898116091&SrchMode=1&sid=3&Fmt=3&VIns t=PROD&VType=PQD&RQT=309&VName=PQD&TS=1128370496&clientId=10762 Proquest Document ID: 898116091 3. Chicago Tribune. Prejudice charge in moderate progression of help supplies. September sixth, 2005 pg. 9 Archive URL: http://proquest.umi.com/pqdweb?index=0&did=892613891&SrchMode=1&sid=6&Fmt=3&VIns t=PROD&VType=PQD&RQT=309&VName=PQD&TS=1128370816&clientId=10762 Proquest Document ID: 892613891
Saturday, August 22, 2020
Communication and Information Technology Essay Example for Free
Correspondence and Information Technology Essay Mechanical progression have improved and facilitated the correspondence procedure. With the world rotating around innovation, practically the sum total of what assignments have been disentangled therefore diminishing the quantity of hours that one can play out a specific errand. It has helped in the sorting out data, consequently empowering access and recovery of data simple. The utilization of innovation has helped numerous associations cut on costs simultaneously expanding effectiveness and immediacy in administration conveyance. In the clinical field, the majority of the up to the standard emergency clinics or social insurance frameworks have received the utilization of innovation in conveying of their administrations. This has realized easily and the sentiment of thankfulness to the patient or the individual who is being filled in as it gives an atmosphere of significant worth for cash and the feeling of grasp of innovation in this mechanical time. Electronic Medical Records is one of these advances (Kluge, 2001). With the ability to hold boundless data and having the option to be changed to fit the present need, this innovation has helped in the human services experts to convey benefits in an increasingly composed way and without having delays when contrasted with if everything was done physically. Significantly, this decreases costs and improves the image of the association simultaneously encouraging observing capacity of the association of the quantity of customers visiting the human services office. Electronic Medical Record is modernized sort of data keeping in which data is packed as it is changed over in an advanced arrangement. This considers utilization of negligible space while keeping the workplace of activity spotless, clean and alluring (Fins, 2008). This production of room empowers the extension of administrations offered in the human services office as there is more space of activity. Access of data turns out to be simple and helpful consequently expanding the resolve of the staff in administration conveyance. It balances the chance of submitting pointless errors while conveying administrations due to written by hand records which are not readable. This program makes it conceivable exchange data starting with one social insurance framework then onto the next accordingly making it conceivable to treat patients in the most brief time conceivable as their clinical records are conveyed in the most brief time conceivable electronically. By utilization of this innovation, it is feasible for guardians to screen their kidsââ¬â¢ prosperity without having additional expense of making a trip to where they are to keep an eye on their advancement. It additionally makes it workable for patients to survey their clinical record and furthermore get their outcomes absent a lot of issue of holding up till they are given to them physically. Other electronic correspondence conveyance administrations like the utilization of voice over have helped in the decrease of the measure of work that one does in calling patients physically with the goal that they can be taken care of. It is only a basic assignment of simply reporting a patients name and they go to the comparing room in which they will be served. This has expanded productivity and viability in serving customers (Fins, 2008). This sets a sort of a request which they patients follow and taking into account simple spread of data, boisterous enough for everybody to hear, accordingly, patients don't need to endure the frustration of not having heard their names being referenced by a guest genuinely since this framework is fitted with speakers sufficiently noisy to be heard unmistakably. Different innovations like the Practice the board programming guarantee the smooth running of the human services framework giving clinical professionals a modest time in their procedure every day. This wads off potential outcomes of disarray and lets them (clinical specialists) work in a systematic way. The data which this product can deal with is comprehensive and doesn't just incorporate the clientââ¬â¢s bio information yet in addition different parts of the social insurance association like bills and exchanges going on. (Klug, 2001) It works only a similar route as the EMR just that it includes the administration part of medicinal services framework in its day by day activities. Aside from keeping a track on patientsââ¬â¢ conditions and arrangements, the framework is utilized to create bills and keep a record on the equivalent so that thee reports can be utilized at whatever point need emerges. It keeps each exchange and movement on record with the goal that it gets workable for any specialist to realize what was done the earlier day and by who, which patient was taken care of and by who so he/she can know precisely where to begin as concerns a particular undertaking. This similarly as the EMRs has a method of reducing expenses and expanding viability. This is on the grounds that all data as concerns any patient is put away electronically and recovered effortlessly when need emerges, therefore maintaining a strategic distance from the chance of befuddling oneââ¬â¢s clinical information with another people (Fins, 2008). This empowers a clinical professional to endorse the correct medication to the perfect individual while simultaneously taking into account age of data about the correct bills for the customer in understanding to the clinical systems and drug concurred to that person. Different frameworks like the electronic wellbeing frameworks keep a full clinical history of a patient. It keeps basic data that can be utilized by the specialist or any clinical expert to offer snappy and compelling conclusion of a patient. All human services reports about a specific patient are put away in this framework including drugs endorsed to the patient each time he/she goes to that social insurance office. It is likewise comprehensive of all test consequences of that specific patient just as x-beams and the reaction of the patient towards a specific medicine. This data is fundamental for up to level human services treatment of any patient. It keeps off the distress of a patient for responding to dreary inquiries regarding their past clinical history each time they visit a human services office, as data about them is put away electronically and recovered on each visit. This clinical history is refreshed time to time on the events that a customer visits to look for treatment. The utilization of electronic innovation in human services frameworks has a greater number of professionals than cons. This is on the grounds that as listed above, it has points of interest to both the customer and the medicinal services office. The way that it expands productivity and adequacy can not be underscored while simultaneously lessening working expenses of the office. Customers are served just as they would prefer and keeping in mind that their clinical record is kept securely and is recovered during the period of scarcity without hardly lifting a finger (Kluge, 2001). One of the significant weaknesses is that data about a patient can be duplicated perniciously and messed with. On the off chance that the whole framework should separate, at that point volumes and volumes of data are lost. It would be something worth being thankful for if all the above framework could be coordinated into one piece. This will ease activity considerably more as all the tasks are under a single tick of a ââ¬Ëmouseââ¬â¢. It could likewise be improved so that customers can get to their data any place and at whatever point they are. Reference Fins, J. (2008). Web of Care: How Will the Electronic Medical Record Change Medicine? The Hastings Center Report, Vol. 38, pp. 67-88 Kluge, E. (2001). The Ethics of Electronic Patient Record
Sunday, August 9, 2020
December and January Holiday Office Hours COLUMBIA UNIVERSITY - SIPA Admissions Blog
December and January Holiday Office Hours COLUMBIA UNIVERSITY - SIPA Admissions Blog The next two weeks the University and SIPA will be recognizing a number of holidays. Below is important information regarding our office hours. We are keeping very busy as the January 5th deadline approaches but if you contact us on any of the following dates you can expect a short delay due to office closures. Thursday, December 23: Office will close at 1:00 PM Friday, December 24: Office closed for the day Monday, December 27: Office closed for the day Thursday, December 30: Office will close at 1:00 PM Friday, December 31: Office closed for the day Monday, January 3: Office closed for the day
Saturday, May 23, 2020
Relationship Between the Society and the Individual...
The society and the individual have a strong and close relationship. It has been noted that an individual is formed and shaped in relation to the society in which he or she grows in. The society provides the individual with the necessities of life and it is the duty of the individual to use these necessities in the most reasonable way without exploitation. The society provides economic, political, cultural and social structures that help the individual carry out his or her daily duties effectively. The society allows the individual achieve his objectives and wishes that he could have not achieved alone. A society can be defined based on its political structure. The society provides an individual a choice on the kind of politics he isâ⬠¦show more contentâ⬠¦This is found on the fact that Tayo had gone to fight against Japan in the Second World War. The Second World War was triggered by thirst for political power among super power countries. In the film ââ¬ËInto the worldââ¬â¢ the director does reveals some aspect of political structure and its effect in the world of McCandless. This is shown where the park rangers warn McCandless that he may not kayak without a license. This shows some of the requirements within a society such as the society of McCandless. In every society there are ways and means which the individual engage in to raise a livelihood. This is defined by the economical structure within the society. There are many and different economic activities available in the society that the individual can engage in. In the current societies this depends on an individualââ¬â¢s qualification and experience. An individualââ¬â¢s qualification is based on his level of education and experience is based on the period in which he has been working in a particular field. Brett (2006, 155-178) states that the economic activity depends on the societyââ¬â¢s geographical location. Geographical location relates to the climatic conditions and the landscape. For example, agriculture may be the main economic activity of a society in the highlands which experience high rainfall. The two works, ââ¬ËCeremonyââ¬â¢ and ââ¬ËInto the wildââ¬â¢ do not explicitly explain the economicShow MoreRelatedContext Taming of the Shrew1767 Words à |à 8 Pagesattention to married life after the wedding. The other comedies usually conclude with the wedding ceremony itself. Themes (the fundamental and often universal ideas explored in a literary work) included throughout this text include Marriage as an economic institution and The Effect of Social Roles on Individual Happiness. As a romantic comedy, the play focuses principally on the romantic relationships between men and women as they develop from initial interest into marriage. In this respect, the playRead MoreFemale to Male as Nature is to Culture Essay2478 Words à |à 10 Pagesare of great interest to anthropologists. Since the feminist movement in the late 1960s, one question that has been discussed is to what extent the opposition between women and men can be thought of in terms of the dichotomy between nature and culture and what implications this has for the position of women in society. This structuralist perspective was first formulated by Ortner (1974), drawing on Levi-Strauss and de Beauvoir, but has since been criticised for being simplisticRead MoreThe Paleo-Indian Tradition Essay2145 Words à |à 9 Pagesand squash. This time period also marked the beginning of pottery as Early Woodland Indians needed proper materials to cook their crops. They also used their pottery to build human burial mounds during this time. The Middle Woodland Indians lived between 300 BC-AD 400. Most southern Indians during this time built their homes around rivers where they could hunt, fish, and collect plants. The northern Indians built their homes, similarly, around the plentiful lakes. The Hopewell people, from centralRead MoreEssay about Summary of History of Graphic Design by Meggs14945 Words à |à 60 PagesWedged shaped writing, created in 3000BC. Started as pictographs. - With the discovery of cuneiform, there was a knowledge explosion, where libraries were organized filling with tablets about religion, mathematics, and history. Writing enabled society to stabilize itself, and laws were created. - Two by-products of the rise of village culture were the ownership of property and the specialization of trades. - Egyptians used hieroglyphics. - The Rosetta Stone, which was created in 196 or 197Read MoreHumanities11870 Words à |à 48 Pagesappreciate art more fully. HUMANITIES: What is it? â⬠¢ The term Humanities comes from the Latin word, ââ¬Å"humanitasâ⬠â⬠¢ It generally refers to art, literature, music, architecture, dance and the theatreââ¬âin which human subjectivity is emphasized and individual expressiveness is dramatized. 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In my vision for the future of science there is greater fusion between scientific research and global health imperatives, creating a more prosperous world through improved health care delivery in the world s most vulnerable regions. The marriage between science, which seeks to address a fundamental biological question, and global health advocacy, which seeks to reduce worldwide health disparities, is aRead MoreThe Philippine Architecture: Spanish Colonial Period18287 Words à |à 74 PagesSpanish Colonial Period Chapter Review Arch 117 Abegail Imee R. Enriquez 2012-68836 Spanish Colonial Period How does Spanish Colonial architecture reflect Filipino identity? Discuss the various building types and their relationship to pre-colonial architecture in your arguments. Spanish colonial architecture reflects Filipino identity mostly through the Religious Architecture. As what the world knows, Philippines is the only Catholic country in Southeast Asia; thus, most of our structures allRead MoreRastafarian79520 Words à |à 319 PagesRastafari: From Outcasts to Culture Bearers is that it correctly traces the connection between the emergence of Rastafarianism and the history of resistance and black consciousness that has been part of the Jamaican experience for years. The truth is that there has always been a committed Jamaican counter- culture that celebrates and sees redemption in Africa and rejects the European values that have oppressed a society. But prior to the advent of popular culture and especially the music recording businessRead MoreDeveloping Management Skills404131 Words à |à 1617 PagesPreface xvii Introduction 1 PART I 1 2 3 PERSONAL SKILLS 44 Developing Self-Awareness 45 Managing Personal Stress 105 Solving Problems Analytically and Creatively 167 PART II 4 5 6 7 INTERPERSONAL SKILLS 232 233 Building Relationships by Communicating Supportively Gaining Power and Influence 279 Motivating Others 323 Managing Conflict 373 PART III GROUP SKILLS 438 8 Empowering and Delegating 439 9 Building Effective Teams and Teamwork 489 10 Leading Positive Change
Tuesday, May 12, 2020
I Have Learned About My Writing - 879 Words
I have learned much from this course and I truly believe that I will take much of this information into my future in education. I learned so much about not only how to write in general, but more specifically my writing too. I think that the greatest factor about my writing that I realized I need to work on is preciseness. I have realized that my writing can be ââ¬Å"beating around the bushâ⬠, and instead of making a paragraph too wordy, I should just get to the point and then analyze. I learned that a beneficial writing strategy can be overviewing the topic briefly, stating the argument, and then using supporting details like quotes and examples that back up the original argument. In high school, I took the International Baccalaureate level of English that my school offered a selected amount of students from beginning of my junior year to the end of my senior year. In those two years we focused really on analyzing poems, Shakespearian plays, and a few novels such as Sula, House of the Spirits, and The Scarlet Letter. We studied intensively how to analyze, annotate, break each part of the novel and ask ââ¬Å"why, what if, how.â⬠Everything I took out of IB help me to this very day when I am reading and examining a novel. However, IB did not teach me how to write a structured essay, I feel like I learned more how to analyze and verbally express my thoughts. We did not write much essays and in those two years. Similarly, I read mostly Shakespearian plays and Elizabeth Bishop poems sinceShow MoreRelatedEssay about What I Have Learned in My English Writing Class1064 Words à |à 5 Pages I have learned many things throughout the course of the term, including such things as: how to write an essay and how to improve on essays that I have already written, how to locate and composite better research through the use of numerous resources found at the campus library, the internet, and the ââ¬Å"Common Senseâ⬠textbook, how to cite research, example s, and quotations properly within the contents of my research paper as well as document it accurately according to MLA standards. Through theRead MoreMy First Time Making A Career Goal1516 Words à |à 7 Pages2015 Lesson Learned To me, this semester has gone by pretty fast and during this semester, I learned so much in this course in a short period of time. I learned how to study different methods of writing and writing in different purposes. I also learned different things just by having online discussions and most importantly, I learned how to improve my writing skills and how this course changed my perception of English and apply it in the future. I have gained so much knowledge about writing in this classRead MoreThe Reflective Essay My Writing Essay1598 Words à |à 7 PagesReflective Essay When I was a child, writing was one of my favorite hobbies, so I used to spend many hours to write in my daily journals. However, when I came to America, I felt more difficult to write and express my thoughts in English because I did not know much vocabularies and lacking grammatical knowledge. Then, I decided to go back to school to improve my writing skills because I recognize the significant of writing in my everyday lives. As a college student, my writing are about different typesRead MoreMy Writing Skills Improved Over The Last Semester950 Words à |à 4 Pages My Writing Skills have improved Over the Last Semester While attending writing class, I learned about the 4 steps in writing, bases for revising, organizing, and connecting specific information, and I also learned about the different types of essays such as descriptive, narrative, process, cause and effect and argumentative essay. I have been a student at Milwaukee Area Technical College for 1 semester, and over the course of my enrollment I have grown and learned more that I knew prior to attendingRead MoreMy Writing : The Reflective Essay Essay1666 Words à |à 7 PagesThe Reflective Essay Writing has been one of my favorite hobbies since I was in high school, so I used to spend many hours to writing in my daily journals in Vietnamese. However, when I came to America, I felt more difficult to write and express my thoughts in English because I did not know much vocabularies and lacking grammatical knowledge. Then, I decided to go back to school to improve my writing skills because I recognize the significance of writing in my everyday lives. As a college studentRead MorePersonal Experience: My Weaknesses and Strenghts as a Writer1470 Words à |à 6 Pagesgrow. I have grown so much since I have started the eighth grade in ways that I love, and ways that I have not yet recognized. I have learned and changed greatly throughout mathematics, science, and history, but I have learned the most about writing properly. Throughout the year, I have changed and recognized my strengths and weaknesses as a writer, my strategies and my progression, and what has caused change and the change to come. My strengths, weaknesses, and preferences as a writer have changedRead MoreReflection About My Writing Process925 Words à |à 4 Pages My writing process have improved thank you to my English 100 level class at Arizona Western College. I feel more confident with my writing style. At the beginning of the class I was very confused with the writing process and the steps to make an essay. I had a difficult time developing an outline and putting together my ideas, so I was not able to write an essay with a good structure. In addition, my grammar was not the best, and some of my sentences were incomplete. During the class period I learnedRead MoreGraduation Speech : My Writing Skills943 Words à |à 4 PagesThroughout the course of DE, I have truly learned a lot and my writing skills have truly improved tremendously. Taking this class has helped me become a better writer and has helped my grammar grow extremely. Another thing that I have gained in this class is stronger sense of vocabu lary words. While writing these papers I have learned the variety of different papers there are. I have learned how to write these papers for future purposes so I will be successful in the long run. My goals as an improvingRead MoreI Feel That I Have Evolved As A Writer In Unimaginable1073 Words à |à 5 Pages I feel that I have evolved as a writer in unimaginable ways. I always had such a difficult time conveying my feelings or sharing them with others; this semester changed that. I started out by writing poems that were very impersonal and lacked depth and emotion. As days and months passed I would remember feelings I had experienced and use those as inspiration and use the numerous techniques learned through this class to form those feelings into a poem. I had dabbled in writing poems prior to takingRead MoreHow I Am My Writing963 Words à |à 4 PagesWhen I looked over my ePortfolio, I couldnââ¬â¢t believe how many pieces of writing I have completed over the course of the semester. I donââ¬â¢t think I have ever written that much in one semester before. When the semester began, I didnââ¬â¢t think this class would change a single thing about my writing. I believed my writing would stay how it has always been. I also believe my writing process wouldnââ¬â¢t change one bit. I have realized that I was wrong. In fact, not only do I think my writing process has changed
Wednesday, May 6, 2020
Reactive Power Based Rotor Resistance Estimation Engineering Essay Free Essays
Abstract-In this paper, a elaborate survey on the Model Reference Adaptive Controller ( MRAC ) using the reactive power is presented for the on-line appraisal of rotor opposition to keep proper flux orientation in an Indirect Vector Controlled Induction Motor Drive. Choice of reactive power as the functional campaigner in the MRAC automatically makes the system immune to the fluctuation of stator opposition. Furthermore, the alone formation of The MRAC with the instantaneous and steady-state reactive power wholly eliminates the demand of any flux appraisal in the procedure of calculation. We will write a custom essay sample on Reactive Power Based Rotor Resistance Estimation Engineering Essay or any similar topic only for you Order Now Therefore, the method is less sensitive to integrator-related jobs like impetus and impregnation ( necessitating no integrating ) . Simulation consequences have been presented to corroborate the effectivity of the technique. THE indirect field oriented ( IFO ) -controlled initiation motor ( IM ) thrust is widely used in high public presentation industry applications [ 1 ] , [ 2 ] due to its simpleness and fast dynamic response. However, feedforward accommodation of the faux pas frequence, which requires rotor opposition, makes this scheme dependant on machine parametric quantities. Of all the parametric quantities, the rotor opposition undergoes considerable fluctuation and if attention is non taken to counterbalance for the alteration, the flux orientation is lost, ensuing in matching between the d- and q-axes variables. As is good known, the yoke makes the public presentation of the thrust system sulky. Attention is focused to implement field orientation through on-line appraisal of the machine parametric quantities [ 3 ] ââ¬â [ 6 ] . Many on-line parametric quantity appraisal strategies are available in literature [ 7 ] ââ¬â [ 20 ] . They are loosely classified as follows Spectral analysis technique Observer based techniques Model mention adaptive system based techniques Heuristic methods Reactive power based technique In one category of method, appraisal of rotor clip changeless is done utilizing the spectral analysis techniques. This group of methods is based on the measured response to a intentionally injected trial signal or an bing characteristic harmonic in the voltage/current spectrum. Stator currents and electromotive forces of the motor are sampled and the parametric quantities are derived from the spectral analysis of these samples. The 2nd categorization of rotor opposition designation strategy used observer based techniques. Most of the methods have used the Extended Kalman Filter, which is a computationally intensive technique [ 11 ] and [ 12 ] . Loron and Laliberte describe the motor theoretical account and the development and tuning of an drawn-out Kalman filter ( EKF ) for parametric quantity appraisal during normal runing conditions without presenting any trial signals. The proposed method requires terminal and rotor velocity measurings and is utile for car tuning an indirect field-oriented accountant or an adaptative direct field-oriented accountant. Zai, DeMarco, and Lipo propose a method for sensing of the reverse rotor clip changeless utilizing the EKF by handling the rotor clip changeless as the 5th province variable along with the stator and rotor currents. The drawbacks are that this method is computationally intensive. The 3rd group of online rotor opposition version methods is based on rules of theoretical account mention adaptative control. This is the attack that has attracted most of the attending due to its comparatively simple execution demands [ 13 ] and [ 14 ] . In add-on to the above methods, there are besides a few techniques proposed which can non be classified in the above three classs. These may be based on the measuring of steady province stator electromotive force, current and motor velocity, the rotor opposition can so be calculated algebraically from the equations derived. These methods are grouped to be Heuristic methods. The chief drawback for the above techniques is that the Rotor Resistance depends on vitamin D and q axis axis rotor flux which in bend depends on Stator Resistance. Therefore if any mistake occurs in the Stator Resistance, the truth of rotor flux deteriorates which in bend affects the truth of estimated Rotor Resistance. Reactive power based rotor opposition calculator [ 1 ] overcomes the disadvantage of above job. Choice of reactive power as the functional campaigner in the Model Reference Adaptive Controller ( MRAC ) automatically makes the system immune to the fluctuation of Stator Resistance. The alone formation of the MRAC with the instantaneous and steady-state reactive power eliminates the demand of any flux appraisal in the procedure of calculation. 2. MRAS based rotor opposition appraisal for vector controlled initiation motor thrusts The parametric quantity can be calculated by the theoretical account mention adaptative system ( MRAS ) , where the end product of a mention theoretical account is compared with the end product of an adjustable or adaptative theoretical account until the mistakes between the two theoretical accounts vanishes to zero. The mistake signal is used to drive an adaptative mechanism ( PI or I controller ) which provides rectification of the rotor opposition. In MRAS, the works ââ¬Ës response is forced to track the response of a mention theoretical account, irrespective of the works ââ¬Ës parametric quantity fluctuation and burden perturbation consequence. Such a system is defined as a robust system. The mention theoretical account may be fixed or adaptative. Choice of reactive power as the functional campaigner in the Model Reference Adaptive Controller ( MRAC ) automatically makes the system immune to the fluctuation of Stator Resistance. The alone formation of the MRAC with the instantaneous and steady-state reactive power wholly eliminates the demand of any flux appraisal in the procedure of calculation. Therefore, the method is independent of Stator Resistance appraisal and integrating impetus jobs. Fig 1 Basic construction of MRAS In the proposed MRAC ( Fig. 1 ) , the mention theoretical account and adjustable theoretical account compute instantaneous reactive power ( ) and steady-state reactive power ( ) severally. Note that the mention theoretical account is independent of slip frequence ( ) whereas the adjustable theoretical account depends on ( ) . The mistake signal ( ) is fed to the version mechanism block, which yields estimated slip velocity ( ) . Rotor opposition ( ) is so computed from ( ) . 2.1 Theoretical Development of the Proposed Scheme The vitamin D and q axis electromotive forces for IM mentioning to the synchronously revolving ( Iâ⬠°e ) mention frame can be expressed as ( 1 ) ( 2 ) The instantaneous reactive power ( Q ) can be expressed as ( 3 ) Substituting ( 1 ) and ( 2 ) in ( 3 ) , the new look of Q is ( 4 ) It is worthwhile to advert that the above looks of Q are free from stator opposition, which is a noteworthy characteristic of any reactive power-based strategy. In steady province the derivative footings are zero. Therefore, the look of estimated reactive power ( ) is obtained as reduces to ( 5 ) 2.2 Evaluations and Parameters of Induction Motor The parametric quantities of the initiation machine used for simulation are given in the Table shown below. Table 2.3 Parameters of 2.2KW 150V, 50Hz 6 Pole Induction Machine Parameters Valuess Stator Resistance ( Rs ) Rotor Resistance ( Rr ) Magnetizing Inductance ( Lm ) Stator Inductance ( Ls ) Rotor Inductance ( Ls ) Inertia Jtot Clash B Rated Current Rated Torque 6.03Ià © 6.085Ià © 0.4893H 0.5192H 0.5192H 0.007187Kgm2 0.0027Kgm2/s 2.9Amps 7.5Nm 2.3 Simulation Consequences The Performance of MRAS based rotor opposition calculator utilizing reactive power method for vector controlled initiation motor thrusts is analyzed with assorted alterations in rotor opposition for the operating status of 415V/50Hz with rated burden torsion of 7.5Nm With 100 % measure alteration in Rotor Resistance. With 100 % incline alteration in Rotor Resistance. With 100 % trapezoidal alteration in Rotor Resistance Fig 2 Actual and Estimated Rotor Resistance for 100 % measure alteration Rr Fig 3 Actual and Estimated Rotor Resistance for 100 % incline alteration Rr Fig 4 Actual and estimated rotor opposition for 100 % trapezoidal alteration Rr From the consequences, it is observed that estimated rotor opposition is tracking with existent rotor opposition. MRAS based Rotor opposition calculator utilizing reactive power method is studied and designed for vector controlled initiation motor thrusts. The public presentation of rotor opposition calculator utilizing reactive power is analyzed extensively for assorted alterations in rotor opposition. From the consequences obtained, it is observed the mistake between that existent and estimated rotor opposition is ever found to be less than 0.9 % and the subsiding clip is found to be about 1 sec. 3. Analysis of vector controlled drive public presentation with and without calculator Vector control is besides known as the ââ¬Å" field oriented control â⬠, ââ¬Å" flux oriented control â⬠or ââ¬Å" indirect torsion control â⬠. Using field orientation ( Clarke-Park transmutation ) , three-phase current vectors are converted to a planar rotating mention frame ( d-q ) from a 3-dimensional stationary mention frame. The ââ¬Å" vitamin D â⬠constituent represents the flux bring forthing constituent of the stator current and the ââ¬Å" Q â⬠constituent represents the torsion bring forthing constituent. These two decoupled constituents can be independently controlled by go throughing though separate PI accountants. The end products of the PI accountants are transformed back to the 3-dimensional stationary mention plane utilizing the opposite of the Clarke-Park transmutation. The corresponding shift form is pulse breadth modulated driving a Voltage beginning Inverter. This control simulates a individually exited DC motor theoretical account, which provides an first-class torque-speed curve. The transmutation from the stationary mention frame to the revolving mention frame is done and controlled with mention to a specific flux linkage infinite vector ( stator flux linkage, rotor flux linkage or magnetising flux linkage ) . In general, there exists three possibilities for such choice and hence, three different vector controls. They are: Stator flux oriented control, Rotor flux oriented control and magnetising flux oriented control. As the torsion bring forthing constituent in this type of control is controlled merely after transmutation is done and is non the chief input mention, such control is known as ââ¬Å" indirect torsion control â⬠. The most ambitious and finally, the confining characteristic of the field orientation, is the method whereby the flux angle is measured or estimated. Depending on the method of measuring, the vector control is divided into two subcategories: direct and indirect vector control. In direct vector control, the flux measuring is done by utilizing the flux feeling spirals or the Hall devices. This adds to extra hardware cost and in add-on, measuring is non extremely accurate. Therefore, this method is non a really good control technique. The more common method is indirect vector control. In this method, the flux angle is non measured straight, but is estimated from the tantamount circuit theoretical account and from measurings of the rotor velocity, the stator current and the electromotive force. One common technique for gauging the rotor flux is based on the faux pas relation. This requires the measuring of the rotor place and the stator current. With current and place detectors, this method performs moderately good over the full velocity scope. The most high-performance VFDs in operation today employ indirect field orientation based on the faux pas relation. The advantages of the vector control are to better the torsion response compared to the scalar control, full-load torsion near to zero velocity, accurate velocity control and public presentation nearing DC thrust, among others. This chapter gives complete inside informations about indirect vector control strategy. Fig 4 Vector controlled Induction Motor Drives The indirect field oriented control presented here is rotor flux oriented control. Figure 4 shows the complete schematic of rotor opposition appraisal for indirect field oriented control of initiation motor thrusts. The torsion bid is generated as a map of the velocity mistake signal, by and large processed through a PI accountant. The torsion and flux bid are processed in the computation block. The three stage mention current generated from the functional block is compared with the existent current in the hysteresis set current accountant and the accountant takes the necessary action to bring forth PWM pulsations. The PWM pulsations are used to trip the electromotive force beginning inverter to drive the Induction motor. 3.3 Simulation Consequences The IFOC thrust public presentation is analyzed without and with calculator for the operating status. Reference speed = 100rad/sec Reference rotor flux = 0.9wb Load torsion = 7.5Nm ( invariable ) Rotor Resistance = 100 % measure alteration in rotor opposition is given at 1 2nd. 3.3.1 Simulation consequence for decoupled stator current for runing status I with and without rotor opposition calculator Fig 3.3 vitamin D and q axis of stator current for runing status I without Rr calculator Fig 3.4 vitamin D and q axis of stator current for runing status I with Rr calculator 3.3.2 Simulation consequence for torsion for runing status I with and without rotor opposition calculator Fig 3.5 Actual and mention torsion for runing status I without Rr calculator Fig 3.6 Actual and mention torsion for runing status I with Rr calculator 3.3.3 Simulation consequence for rotor flux for runing status I with and without rotor opposition calculator Fig 3.7 Actual and mention rotor flux for runing status I without Rr calculator Fig 3.8 Actual and mention rotor flux for runing status I with Rr calculator 3.5 Significance of Estimation clip on the thrust public presentation In the execution of the calculators, the clip taken for appraisal is an of import parametric quantity. Faster tracking will take to better dynamic public presentation. The cost of the calculator should be low to maintain the cost of the thrust system within the allowable degrees. Hence a survey on the thrust public presentation has been done for assorted appraisal times and the torsion and the flux responses are observed. The consequences are tabulated in Table 3.2 and 3.3. The appraisal clip decides the transeunt public presentation indices like settling clip and peak wave-off in both torsion and flux responses of the vector controlled thrust. The appraisal mistake has less impact on the transeunt public presentation. However the steady province mistake in both torsion and flux response chiefly decided by the appraisal mistake. The thrust public presentation is analyzed with assorted calculators in which the appraisal mistake is kept changeless at 1 % and clip of appraisal is varied. The appraisal mistake and appraisal clip of the vector controlled initiation motor thrust is analyzed for the operating status for mention velocity 100rad/sec, mention rotor flux 0.9wb, the rated burden torsion ( 7.5Nm ) is reduced to 5.5Nm,40 % measure alteration in rotor opposition is given at 2 second.From this the transeunt response in torsion and flux are studied. Table 3.3 Flux Response for Various Estimation Times Table 3.2 Torque Response for Various Estimation Times ESTIMATION TIME ( sec ) Settling TIME ( sec ) PEAK OVERSHOOT ( % ) No hold ââ¬â ââ¬â 8*10-3 0.2 0.45 20*10-3 0.23 1.55 30*10-3 0.25 4.95 80*10-3 0.27 6.75 100*10-3 0.55 8.29 1 1.2 11.25 ESTIMATION TIME ( sec ) Settling TIME ( sec ) PEAK OVERSHOOT ( % ) No hold ââ¬â ââ¬â 8*10-3 0.11 2.95 20*10-3 0.14 6.55 30*10-3 0.17 10.72 80*10-3 0.2 16.33 100*10-3 0.55 16.55 1 1.15 16.65 Table 3.5 Flux Response for Various Estimation Mistakes Table 3.4 Torque Response for Various Estimation Mistakes ESTIMATION ERROR ( % ) Steady STATE ERROR ( % ) 0 0 0.4 0 1 0.26 1.5 0.44 2 0.65 3 0.71 5 1.03 ESTIMATION ERROR ( % ) Steady STATE ERROR ( % ) 0 0 0.4 0 1 0.39 1.5 0.50 2 0.70 3 0.95 5 1.11 Similarly with same runing conditions the steady province analysis of the torsion and flux response of the thrust can be done by holding the appraisal clip as changeless with assorted appraisal mistakes. The public presentation is studied with a changeless appraisal clip of 20ms. The Torque and the flux responses for the above conditions are tabulated in Table 3.4 and 3.5. The bold Numberss shown in table 3.2, 3.3, 3.4 and 3.5 are the optimal allowable values of the appraisal clip and appraisal mistake. It is obvious that as the appraisal clip and the appraisal mistake are increased the thrust public presentation is being deteriorated. However it is quiet appealing to settle down with the maximal allowable appraisal clip and appraisal mistake, so that the thrust public presentation is satisfactory. Therefore from the consequences it can be concluded that the public presentation of the thrust is satisfactory with the maximal appraisal clip of 20ms and an appraisal mistake of 1.5 % . 4. Decision The MRAS based Rotor opposition calculator utilizing reactive power method is studied and designed for vector controlled initiation motor thrusts. The public presentation of rotor opposition calculator utilizing reactive power is analyzed extensively for assorted alterations in rotor opposition. From the consequences obtained, it is observed the mistake between that existent and estimated rotor opposition is ever found to be less than 0.9 % and the subsiding clip is found to be about 1 sec. The public presentation of Vector Controlled Induction Motor Drive with and without Rotor Resistance calculator is studied. From the consequences, it is observed that the without rotor opposition calculator, the decouple control is lost which leads to important deteriorates in the public presentation of vector controlled initiation motor thrusts while with rotor opposition calculator, the decouple control is achieved and the public presentation of IFOC is truly enhanced. The maximal allowable appraisal mistake and appraisal clip for rotor opposition appraisal that does non deteriorate the public presentation of IFOC is found to be 1.5 % and 20ms severally. How to cite Reactive Power Based Rotor Resistance Estimation Engineering Essay, Essay examples
Saturday, May 2, 2020
Effects Of The Treaty Of Versailles On Germany Essay Example For Students
Effects Of The Treaty Of Versailles On Germany Essay The Effects of the Treaty of Versailles on GermanyWorld War I was one of the bloodiest and deadliest wars of all time. Many agreed that there were to be no more wars hence a treaty was signed. However, the contents of the treaty were not to Germanys favour. The treaty of Versailles had a great role in Germanys decision and desire to enter into war. After Germany had surrendered and WWI was at an end, many, especially France, wanted to punish Germany. At the Paris peace conference, which the Germans were not invited to , ideas for a treaty were presented. There were many articles, 440 to be exact, that were included in the treaty. Germany was forced to give up all foreign businesses. Germany was not able to have soldiers within 100 kilometers of the border. As a result they could not defend themselves well enough. Germanys navy, army, and airforce was destroyed. Any remaining ships and planes were blown up and/or sunk. Germany was only allowed to keep 24 ships and no submarines. They were also to limit their naval personnel to 15,000 people. Germany was to stop inporting, exporting, and producing war related material. The German army was reduced to 100,00 soldiers which was lower than the number of soldiers that they had in WWI. France decided that they would take back their old land of Alsasce and Lorraine. Germany was ordered to pay reparations for the damage that they caused in WWI. Theses reparations were not only payed with money but also in the form of ships, trains, livestock, and valuable resources. According to W.M. Jordan, these were the most important parts of the treaty of Versailles.BibliographythertMythology Essays
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