Sunday, September 29, 2019
Unit 4 Essay
Unit 4 assignment instructions This week, our writing assignment focuses on individual definitions of happiness. For this writing assignment, you will prepare and conduct interviews with two people about their definition of happiness, how they gained this view, and whether they feel happiness is achievable. Choose two people who vary in age and experience. Only one of the subjects can be someone you know well. This is an opportunity to learn about acquaintances and strangers as well. These should be face-to-face interviews.Introduce this assignment by introducing each subject one at a time. Who are they? What is the nature of your relationship? Next, ask a variety of questions to get them to consider not just their definition of happiness, but its origins and development. You can use these sample questions to get you started, but should add more questions or change the interview as it develops: Has your definition of happiness changed over time? What experiences have influenced your definition? Do you expect the definition to change again?Follow the Unit 4 template for this assignment in DocSharing. It includes submitting a transcript of your interviews, including your questions, so take notes or record the discussion. Finally, you should draw conclusions about the process and the answers that were given. Compare and contrast the results of the interviews. Discuss what was similar or different in the replies, whether the subjects were honest, or if the concept of happiness was difficult to define. The essay should be at least 750 words and should employ terms from the text.The assignment should be completed in Microsoft Word and should follow the template provided for the sample transcript, essay, and reference page. CLA assessment: This unit 4 assignment corresponds to the CLA rubric for HU300-02; please review the CLA rubrics document available under Course Home. APA formatting: Incorporate APA citations throughout the analysis as well as a references section at the end of the analysis. (The references section does NOT count towards the required word count for the Unit 4 assignment. ) Review the APA quick reference guide on the left-hand sidebar under course home for APA formatting guidelines.
Saturday, September 28, 2019
Propeller
ELECTRICAL ENGINEERING ââ¬â Vol. III ââ¬â Direct Current Machines ââ¬â Edward Spooner DIRECT CURRENT MACHINES Edward Spooner The University Of New South Wales, Australia. Keywords: Electric machines, dc motor, electromagnetic induction, Faraday's Law, commutator. Contents U SA NE M SC PL O Eââ¬â C EO H AP LS TE S R S 1. Introduction 2. Magnetism and Electromagnetic principles 2. 1. Permanent Magnets 2. 2. Magnetic Field around Conductors 2. 3. Magnetic Field around a Coil 2. 4. Electromagnets 2. 5. Magnetic Strength of Electromagnets 2. 6. Electromagnetic Induction 3. Current Carrying Wires and Coils 3. . Force on a Wire in a Magnetic Field 3. 2. Force and Torque on a Coil in a Magnetic Field 4. Basic Motor Principles 4. 1. The Commutator and Motor Action 4. 2. Simplified Version of the dc Motor 4. 3. Sizes of Machines (related to Torque) 4. 4. Construction of Motors 4. 5. The Stator of a dc Machine 4. 6. Rotor 4. 7. The Commutator 4. 8. Electromotive Force (EMF) in d c Machines 5. Machine equations and circuits 5. 1. Basic Equivalent Circuit of a dc Motor. 5. 2. Direct current Motor Operation & Torque generation 5. 3 DC Machine Torque Equations 5. 4. DC Machine Equations and Speed Regulation . 5. Machine Power and Losses 6. Types of dc Machine 6. 1. Permanent Magnet 6. 2 Shunt Wound 6. 3 Separately Excited 6. 4. Series Connected 6. 5. Compound Connected Motor 7. Stepper Motors 7. 1. General 7. 2. Permanent Magnet Stepper Motors 7. 3. Reluctance Stepper Motors 7. 4. Torque ââ¬â Step Rate 8. Conclusions à ©Encyclopedia of Life Support Systems (EOLSS) ELECTRICAL ENGINEERING ââ¬â Vol. III ââ¬â Direct Current Machines ââ¬â Edward Spooner Glossary Bibliography Biographical Sketch Summary This chapter gives a background to the principles behind the operation of dc motors and stepper motors.Permanent magnet, shunt, separately excited, series and compound wound dc motor connections are described. A description of the equations behind the basic behavior of these machines is given and the torque vs speed and speed vs armature (voltage and current) characteristics are illustrated, which gives a background to the control of these motors. U SA NE M SC PL O Eââ¬â C EO H AP LS TE S R S 1. Introduction Electrical machinery has been in existence for many years. The applications of electrical machines have expanded rapidly since their first use many years ago.At the present time, applications continue to increase at a rapid rate. The use of electrical motors has increased for home appliances and industrial and commercial applications for driving machines and sophisticated equipment. Many machines and automated industrial equipment require precise control. Direct current motors are ideal for applications where speed and torque control are required. Direct current motor design and complexity has changed from early times where dc machines were used primarily for traction applications.Direct current motors are used for vario us applications ranging from steel rolling mills to tiny robotic systems. Motor control methods have now become more critical to the efficient and effective operation of machines and equipment. Such innovations as servo control systems and industrial robots have led to new developments in motor design. Our complex system of transportation has also had an impact on the use of electrical machines. Automobiles and other means of ground transportation use electrical motors for starting and generators for their battery-charging systems.Recently there have been considerable developments in electric vehicles and also in hybrid electric vehicles which use a combination of a dc motor and an internal combustion engine for efficient operation. In this chapter machines driven by dc electrical supplies are considered. Since the operation of this type of machine is based upon the flow of current in conductors and their interaction with magnetic fields, common principles that underlie the behavior of dc machines will be examined first. 2. Magnetism and Electromagnetic PrinciplesMagnetism and electromagnetic principles are the basis of operation of rotating electrical machines and power systems. For this reason, a review of basic magnetic and electromagnetic principles will be given. à ©Encyclopedia of Life Support Systems (EOLSS) ELECTRICAL ENGINEERING ââ¬â Vol. III ââ¬â Direct Current Machines ââ¬â Edward Spooner 2. 1. Permanent Magnets Permanent magnets are generally made of iron, cobalt, nickel or other ââ¬Ëhardââ¬â¢ magnetic materials, usually in an alloy combination. The ends of a magnet are called north and south poles.The north pole of a magnet will attract the south pole of another permanent magnet. A north pole repels another north pole and a south pole repels another south pole. The two laws of magnetism are: 1) Unlike poles attract (see Figure 1); 2) Like poles repel (see Figure 2). U SA NE M SC PL O Eââ¬â C EO H AP LS TE S R S The magnetic field patterns when two permanent magnets are placed end to end are shown in Figures 1 and 2. When the magnets are farther apart, a smaller force of attraction or repulsion exists. A magnetic field, made up of lines of force or magnetic flux, is set up around any magnetic material.These magnetic flux lines are invisible but have a definite direction from the magnetââ¬â¢s north to south pole along the outside of the magnet. When magnetic flux lines are close together, the magnetic field is stronger than when further apart. These basic principles of magnetism are extremely important for the operation of electrical machines. Figure 1: Unlike poles attract Figure 2: Like poles repel 2. 2. Magnetic Field around Conductors Current-carrying conductors, such as those in electrical machines, produce a magnetic field. It is possible to show the presence of a magnetic field around a current-carrying conductor.A compass may be used to show that magnetic flux lines around a conductor are circ ular in shape. à ©Encyclopedia of Life Support Systems (EOLSS) ELECTRICAL ENGINEERING ââ¬â Vol. III ââ¬â Direct Current Machines ââ¬â Edward Spooner A method of remembering the direction of magnetic flux around a conductor is the right-hand ââ¬Å"cork-screwâ⬠rule. If a conductor is held in the right hand as shown in Figure 3, with the thumb pointing in the direction of current flow from positive to negative, the fingers then encircle the conductor, pointing in the direction of the magnetic flux lines. U SA NE M SC PL O Eââ¬â C EO H AP LSTE S R S Figure 3: Right-hand rule The circular magnetic field is stronger near the conductor and becomes weaker at a greater distance. A cross-sectional end view of a conductor with current flowing toward the observer is shown in Figure 4. Current flow towards the observer is shown by a circle with a dot in the centre. Notice that the direction of the magnetic flux lines is counter-clockwise, as verified by using the right-ha nd rule. Figure 4: Current out of the page When the direction of current flow through a conductor is reversed, the direction of the magnetic lines of force is also reversed.The cross-sectional end view of a conductor in Figure 5 shows current flow in a direction away from the observer. Notice that the direction of the magnetic lines of force is now clockwise. Figure 5: Current into the page à ©Encyclopedia of Life Support Systems (EOLSS) ELECTRICAL ENGINEERING ââ¬â Vol. III ââ¬â Direct Current Machines ââ¬â Edward Spooner When two conductors are placed parallel to each other, and the direction of current through both of them is the same, the magnetic field lines amalgamate to become one and the two conductors attracted together. See Figure 6. Figure 6: Two parallel conductors U SA NE M SC PL O Eââ¬â C EOH AP LS TE S R S The presence of magnetic lines of force around a current-carrying conductor can be observed by using a compass. When a compass is moved around the o utside of a conductor, its needle will align itself tangentially to the lines of force as shown in Figure 7. Figure 7: Field's effect on a compass When current flow is in the opposite direction, the compass polarity reverses but remains tangential to the conductor. 2. 3. Magnetic Field around a Coil The magnetic field around one loop of wire is shown in Figure 8. Figure 8: Loop of wire à ©Encyclopedia of Life Support Systems (EOLSS) ELECTRICAL ENGINEERING ââ¬â Vol.III ââ¬â Direct Current Machines ââ¬â Edward Spooner U SA NE M SC PL O Eââ¬â C EO H AP LS TE S R S Magnetic flux lines extend around the conductor as shown when current passes through the loop. Inside the loop, the magnetic flux is in one direction. When many loops are joined together to form a coil as shown in the Figure 9, the magnetic flux lines surround the coil as shown in Figure 10. The field produced by a coil is much stronger than the field of one loop of wire. The field produced by a coil is simil ar in shape to the field around a bar magnet. A coil carrying current, often with an iron or steel core inside it is called an electromagnet.The purpose of a core is to provide a low reluctance path for magnetic flux, thus increasing the flux that will be present in the coil for a given number of turns and current through the coil. Figure 9: Coil formed by loops Figure 10: Cross-sectional view of the above coil 2. 4. Electromagnets Electromagnets are produced when current flows through a coil of wire as shown below. Almost all electrical machines have electromagnetic coils. The north pole of a coil of wire is the end where the lines of force exit, while the south polarity is the end where the lines of force enter the coil.To find the north pole of a coil, use the right-hand rule for polarity, as shown in Figure 11. Grasp the coil with the right hand. Point the fingers in the direction of current flow through the coil, and the thumb will point to the north polarity of the coil. When the polarity of the voltage source is reversed, the magnetic poles of the coil reverse. Figure 11: Finding the north pole of an electromagnet à ©Encyclopedia of Life Support Systems (EOLSS) ELECTRICAL ENGINEERING ââ¬â Vol. III ââ¬â Direct Current Machines ââ¬â Edward Spooner The poles of an electromagnet can be checked by placing a compass near a pole of the electromagnet.The north-seeking pole of the compass will point toward the north pole of the coil. 2. 5. Magnetic Strength of Electromagnets The magnetic strength of an electromagnet depends on three factors: (1) the amount of current passing through the coil, (2) the number of turns of wire, and (3) the type of core material. The number of magnetic lines of force is increased by increasing the current, by increasing the number of turns of wire, by decreasing any air gap in the path of the magnetic flux, or by using a more desirable type of core material. . 6. Electromagnetic Induction U SA NE M SC PL O Eââ¬â C E O H AP LS TE S R S The principle of electromagnetic induction is one of the most important discoveries in the development of modern electrical technology. Electromagnetic induction is the induction of electric voltage in an electrical circuit caused by a change in the magnetic field coupled to the circuit. When electrical conductors, such as alternator windings, are moved within a magnetic field, an electrical voltage is developed in the conductors.The electrical voltage produced in this way is called an induced voltage. A simplified illustration showing how induced voltage is developed is shown in Figure 12. Michael Faraday developed this principle in the early nineteenth century. Figure 12: Faraday's Law If a conductor is placed within the magnetic field of a horseshoe magnet so that the left side of the magnet has a north pole (N) and the right side has a south pole (S), magnetic lines of force travel from the north pole of the magnet to the south pole.The ends of the conductor i n Figure12 are connected to a volt meter to measure the induced voltage. The meter can move either to the left or to the right to indicate the direction and magnitude of induced voltage. When the conductor is moved, the amount of magnetic flux contained within the electrical circuit (which includes the wire and the connections to the meter and the meter itself) changes. This change induces voltage through the conductor. Electromagnetic induction takes place whenever there is a change in the amount of flux coupled by a circuit.In this case the motion of the conductor in the up direction causes more magnetic flux to be contained within the circuit and the meter à ©Encyclopedia of Life Support Systems (EOLSS) ELECTRICAL ENGINEERING ââ¬â Vol. III ââ¬â Direct Current Machines ââ¬â Edward Spooner needle moves in one direction. Motion of the conductor in the down direction causes less magnetic flux to be coupled by the circuit and the meter needle moves in the opposite directi on. The principle demonstrated here is the basis for large-scale electrical power generation.In order for an induced current to be developed, the conductor must be in a complete path or closed circuit, the induced voltage will then cause a current to flow in the circuit. 3. Current Carrying Wires and Coils The basic requirement of any electrical machine, whether ac or dc, is a method of producing torque. This section explores how two magnetic fields in a machine interact to produce a force which produces a torque in a rotating machine. U SA NE M SC PL O Eââ¬â C EO H AP LS TE S R S ââ¬â TO ACCESS ALL THE 34 PAGES OF THIS CHAPTER, Visit: http://www. eolss. net/Eolss-sampleAllChapter. spx Bibliography Clayton, Albert E. , Hancock N. N. [1959] ââ¬Å"The performance and design of direct current machines. â⬠Pitman Edwards J. D. (1991) ââ¬Å"Electrical machines and drives : an introduction to principles and characteristics. â⬠Basingstoke : Macmillan Fitzgerald A. E. , Kinglsey C. Jr. , (1961) ââ¬Å"Electric Machineryâ⬠2nd Edition, McGraw Hill. [Comprehensive text on electric machines. ] Guru B. S. , Hiziroglu H. R. , (2001) ââ¬Å"Electric Machinery and Transformersâ⬠3rd Edition, New York, Oxford University Press. [Good general text on electrical engineering including machines. Say M. G. (1983). Alternating Current Machines, 5th Edition, London: Pitman. [This covers the more advanced theory of electrical machines] Biographical Sketch E. D. Spooner graduated from the University New South Wales, Australia, and obtained his ME in 1965. He is currently a project leader for Australiaââ¬â¢s Renewable Energy Systems testing Laboratory and Lecturer in Electrical Engineering. His research has covered power electronics and drives and is currently focused in renewable energy systems. à ©Encyclopedia of Life Support Systems (EOLSS)
Friday, September 27, 2019
Services Directive Essay Example | Topics and Well Written Essays - 1750 words
Services Directive - Essay Example Services Directive The first of these is that the implementation of the application of the country of origin principle, which requires that only the law of the country in which the service provider is located should be applicable. Further, it enjoins upon the Member States not to restrict in a discriminatory way services from a provider established in another Member State. Second, empowering citizens to use the services provided by any other Member State without being delayed or discouraged by restrictive measures imposed by their country. Third, creation of a mechanism to provide assistance to citizens who use a service provided by an operator established in another Member State and fourth, the allocation of tasks between the Member State of destination and origin, in respect of the posting of workers. This directive is not applicable to non ââ¬â economic and non ââ¬â remunerated activities. Hence, it is not applicable to the non ââ¬â remunerated activities of the governments of Member states in respect of its cultural, educational, legal and social commitments towards its citizens . The origins of this directive lie in the questions thrown up by the incident described in the next few lines; a liqueur, Crà ¨me de Cassis, was not allowed to be imported and sold in Germany by the importers Rowe-Zentral AG. The reason for this was cited as low alcoholic content for that particular type of alcoholic drink. The importer approached the European Court of Justice, which challenged the validity of national legislation that was attempting to introduce non ââ¬â tariff barriers to trade. ... The importer approached the European Court of Justice, which challenged the validity of national legislation that was attempting to introduce non - tariff barriers to trade.2 One of the main bastions of the free movement of goods within the EU is the principle of mutual recognition. Its genesis lies in the above cited EU Court of Justice famous Cassis de Dijon judgment of February 20, 1979. This principle requires that, every Member State to accept products on its territory which are legally produced and marketed in another community Member State. The right of Member States is restricted to challenging this principle in cases involving risk to public safety, health or the environment. In such cases the measure taken must be in conformity with the principles of necessity and proportionality. On the 4th of November 2003, the European Commission published a communication aimed at illuminating the principle of mutual recognition.3 A businessman is often forced to abstain from selling a product, which does not satisfy the technical rules of that Member State, owing to ignorance as to how to proceed in such a discriminatory situation. A technical rule gives the specifications which define the features necessary in a product like its composition, presentation, packaging, labelling etc. The aim of this communication is to spell out the rights and methods of appeal which economic operators may derive from the principle of mutual recognition, when they encounter such difficulties. On the whole, wherever provisions of a national law are incompatible with the principle of mutual recognition, the national courts and administrations have to guarantee the full impact of the principle by removing, of their own
Thursday, September 26, 2019
Film and Media Studies - History of Broadcasting - Advertising the Essay
Film and Media Studies - History of Broadcasting - Advertising the American Dream - Essay Example Pepsi takes this parable a step further with their commercial. Before drinking the Pepsi, the boy is uninspired and most likely tired of the life he is currently living. After drinking the Pepsi, he is filled with energy and uses this energy to practice drumming around town. He does not have a drum set, probably because of his familyââ¬â¢s economic status and capital, and he does not need one because he drank Pepsi and now he can achieve the once-thought-of-as impossible. A young Hispanic boy starts off in by an apartment complex in this commercial, and by using an urban Hispanic setting with a monotone color scheme, a sense of confinement is instilled and something must be done about it. With this set-up, Pepsi comes in to ââ¬Å"save the dayâ⬠or, in this case, this boyââ¬â¢s life from normality. Pepsiââ¬â¢s product promises to lift this particular Hispanic youth out of a lower-middle class inner-city barrio environment into a drummer for a popular band. Once the boy has tried the product, he becomes inspired giving him confidence and motivation to follow his dream of becoming a drummer. And while everyone else is still living their mundane lives, he has transcended this barrio environment to pursue his dream. He ascends to the high-class stardom status instantaneously in the commercial. He is suddenly taken out of the boring lifestyle he was living in, ages about ten years older, and is put in a rock band on stage entertaining a massive crowd of fans most likely with his professional drumming. The boyââ¬â¢s younger years are portrayed in the sunlight, but not necessarily in a cheerful, happy way. The sun just seems to be part of the whole monotonous picture. When the boyââ¬â¢s dream is finally reached, the whole set-up is changed. Instead of it being day, it is night (or at least in an indoor stadium or concert hall). The only light is the light coming from the stage lights, which represent the
Technology in business Assignment Example | Topics and Well Written Essays - 750 words
Technology in business - Assignment Example Taking responsibility for action would be important where working with the customer to find a solution would help the situation. I would also give discount for the next time they visit the cafà ©. I would explain to them that we understand their concern and take responsibility for any inconveniences caused. In doing so, I would explain to them that the children story hour was created due to the customerââ¬â¢s request that have kids. The customers requested the space to enable the children in the community to build a culture of reading and other kids during the summer can read storybooks. The cafà © is built to serve the community at large and would inquire that if they were willing to understand the cafà © situation and program. I would inform him that the cafà © takes his comment with the seriousness it deserves and would come up with an appropriate solution. Finally, I would apologize for the inconvenience by the children and appreciate tis chance for enabling the cafà © to identify a problem that would lead to its growth. I would inform him the cafà © would try to find a separate area for regular customers and a different area for the children and offer discounts for future visits to the cafà ©. The customers viewpoint is unethical about itââ¬â¢s about the rights. The customer has the right to suggest and request anything they please. However, parents also have the right to bring their children anywhere they would want including the cafà ©. To encourage an open line of communication with the customers and still maintain an open forum for the website it is good to appreciate that the event is unusual and that the cafà © values the customers and that the customers will appreciate the business idea of serving the community. The cafà © may decide to open a free forum where customers can be able to leave their comments and suggestions about any issues regarding the cafà ©. All
Wednesday, September 25, 2019
European Union Law Essay Example | Topics and Well Written Essays - 1500 words
European Union Law - Essay Example In its logical form, the treaty seeks to promote free movement of goods to bridge the cross-border gap that exists between different European Union countries. Even regardless of such laws and treaty, some countries have been found to be putting undue restrictions on fellow European Union countries so that there would be a concentration of market in those countries. The strategy used by those who put the restrictions has been to place huge charges on cross border goods to discourage free movement. In response, Articles 23(1) and 25 (9(1) and 12) ECT of the treaty touches on prohibition of charges having an effect equivalent to that of customs duties, which discourages all such charges to the exclusion of a similar domestic product (European Parliament Fact Sheets, 2012). Relevant primary and secondary legislation From CJ Case 8/74, 11 July 1974, it could be seen that with reference to Olio Nuovo, Article 28(30), ECT of the Treaty on the Functioning on the functioning of the European U nion (TFEU) can be applied to its logical conclusion to give him a lot of legal redress to the current situation in which he finds himself. In the first play, there is a primary legislature on the free movement of goods and services within the European Union region (Kuyper, 1993). As a marketer from Greece to Italy, Olio Nuevo is covered by this primary legislation because both countries are within the European Union zone. This is a very strong basis for Nuevo to begin any legal process with an ambition of putting forth legal damages for any losses that he might have recorded. This is because according to the case in which Nuevo finds himself, there is being an unconstitutional attempt of hindering, directly or indirectly, actually or potentially, intra-Community trade, which the European Parliament Fact Sheets (2012), states that ââ¬Å"are to be considered as measures having an effect equivalent to quantitative restrictions.â⬠What is more, there are secondary laws such as th ose that specify the kind of products and materials that could cross European Union neighbouring borders. Examples of such European Union laws are those on the forbidding of arms and drugs trade. Since Nuevo did not attempt to trade any of such illegal products, there also is a very strong legal case to be heard should Nuevo decide to pursue the case to its legal conclusion. Exceptions to the Rule As it is literary said, to every rule there are exceptions. The Treaty on the Functioning on the functioning of the European Union (TFEU), which makes previsions for free movement of trade across European Union members States borders also have its own legal limitation or exceptions as far as the application of the rules are concerned. Under Article 30 (36) of ECT of the treaty, factors such as protection of public health, public morality and public security are all captured as exemptions under which Member States may take personal measures on having effect equivalent to quantitative (Europ ean Parliament Fact Sheets, 2012). This means is that the interest of the consumer always comes first when dealing with the movement of good (Eeckhout and Govaere, 1992). The legal implication here is that the host country where Nuevo wants to start
Tuesday, September 24, 2019
Packet Data Transmission Essay Example | Topics and Well Written Essays - 2500 words
Packet Data Transmission - Essay Example The transport layer establishes a session management between the two hosts. Data received from the application layer is segmented into packets. Each packet is given a unique label before being transmitted. The packets contain the necessary information that is sent to the host computer to fetch a web page; these packets are transmitted to the internet layer. The internet layer constitutes the Internet Protocol (Parziale, 2006). Data is packaged into Internet Protocol datagrams, which hold the address details of the client and server. The addresses of the client and server side are referred to as IP addresses (Osterloh, 2001). The packets are then transmitted to network interface layer. The network interface layer is responsible for determining how data is transmitted over the network (Rufi, 2008). The transmission of data is dependent on the network medium used, for example, Ethernet and the optical fiber. TCP/IP protocol stack In order for communication to be effective, the internet protocol is based on the TCP/IP model. The TCP/IP constitutes protocols, mainly the Transmission Control Protocol (TCP) and the Internet Protocol (IP), hence the name but there exist other protocols as well. The TCP/IP is a hierarchical model composed of interactive modules where each module is assigned a specific task (Bonaventure, 2011, p.75). The layers in the model are composed of protocols that can relate to each other depending on the system type. In terms of hierarchy, a number of layers below the higher layer protocols support it.
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