Journal entry on Cathedral by Raymond Carver

In the story cathedral by Raymond Carver, the author who is also the persona introduces a blind man who is an old friend of his wife (Schneider par 1). He revealed how the old man met his wife some years back. Being the persona in the story, he unfolds how the blind man met his lovely wife and how she died of cancer later.Advertising We will write a custom critical writing sample on Journal entry on Cathedral by Raymond Carver specifically for you for only $16.05 $11/page Learn More The persona felt unease with the blind man since he could not understand some of the things the man would do like smoking and not wearing dark glasses (Carver 187). He also felt uncomfortable with his wife’s relationship with the blind man and experienced a lot of discontent in the discussion. Meanwhile, the persona has used his skills to develop themes and symbols that have substantially created the plot of his story. Being the protagonist in the story, he deliberatel y engages the audience in his narration as he exposes human transformation. It is against this background that this essay explores the character traits of Carver as a person of partial understanding who is ignorant to approach reality by his aptitude to socialize with the blind man. Besides, the essay offers a personal reflection and experience on the entire take from the story. To begin with, it is imperative to note that Carver’s work evokes a feeling of envy and pity in the character of the blind man. The narrator reveals how the blind man’s wife died of cancer yet he never look at her because he could not see. He reveals that the blind man could not understand the TV show and at times Caver was forced to explain it to him. However, this blind man is envied by the persona for his exact outlook of the world than those with sight (Carver 191). The persona is dumbfounded by the kind of liaison the blind man has with his wife. In the phrase† When we first started going out together, she showed me the poem† (Carver 188), indicates that he did not like the relationship at all He is amazed that, though the man is blind he is far exposed beyond the blind world and, like learning new thing as they surface. In the phrase â€Å"I’m always learning something. Learning never ends. It won’t hurt me to learn something tonight. I got ears,† (Carver 193). I get enlightened by the way the blind man appears sharp and optimistic to life’s issues. He seemed not ignorant of emerging issues since he was ready to learn by himself. The narrator opted to dislike the coming of the blind man into his house yet, he never new that he was canopied by his own ignorance. In the quote, â€Å"My idea of blindness came from the movies. In the movies, the blind moved slowly and never laughed. Sometimes they were led by seeing-eye dogs.Advertising Looking for critical writing on american literature? Let's see if we can help you! Get yo ur first paper with 15% OFF Learn More A blind man in my house was not something I looked forward to.† (Carver 186), it is evident that he was agitated by the blind man’s visit in his house. In the first place, he new less about the man and he judged him from his previous experience of a blind man from a movie (Carver 186). Out of his ignorance, he thought that blind men wore black glasses and that they did not smoke (Carver 190). In my opinion, I do not identify with such a character that holds things with ignorance. Instead, it is wise to be of open minded in order to discover more of what we know and not judge things by their appearance. Additionally, one should not be envious when proved ignorant in some issues. My impression has been positively transformed from being pessimistic about other people’s disabilities. I felt the need to be sensitive to new issues in order to wipe away ignorance of past experiences. Moreover, I should not look down upon p eople by their look without a clear evaluation of their potential. There before, I read the story of ‘A doll house’ by Henrik Ibsen and it reflects to the story â€Å"Cathedral† in the fact that, there are characters that are ignorant on issues adjoining them. For example in â€Å"A doll house†, Torvald was ignorant of his wife naivety only to realize later that she was playing on him. The same happened to the persona in the story of â€Å"Cathedral† where the persona is proved wrong of his ignorance about the blind man. The similarity between the two stories is that both the authors are the personas in the plots. The difference arises where â€Å"A doll house† is a play while â€Å"Carver† is a short story. In summing up, it is vital to reiterate the fact that the author managed to develop his plot well by creating themes depicting the nature of modern society. These include ignorance, religion and diversity of beliefs. He also used s ymbolism in his work hence emerged creative. Works Cited Carver, Raymond. Cathedral. New York: Random House. 2009. Print.Advertising We will write a custom critical writing sample on Journal entry on Cathedral by Raymond Carver specifically for you for only $16.05 $11/page Learn More Schneider, Dan. Cathedral by Raymond Carver. 2005. 23 Aug. 2011. Web. This critical writing on Journal entry on Cathedral by Raymond Carver was written and submitted by user Frank V. to help you with your own studies. You are free to use it for research and reference purposes in order to write your own paper; however, you must cite it accordingly. You can donate your paper here.

Biography of Woodrow Wilson, 28th U.S. President

Biography of Woodrow Wilson, 28th U.S. President Woodrow Wilson (December 28, 1856–February 3, 1924) was the 28th president of the United States, serving from 1913 to 1921. Prior to that, Wilson was the governor of New Jersey. Although he won reelection with the slogan He kept us out of war, Wilson was the commander-in-chief when the country finally entered World War I on April 6, 1917. Fast Facts: Woodrow Wilson Known For: Wilson was the president of the United States from 1913 to 1921.Born: December 28, 1856 in Staunton, VirginiaParents: Joseph Ruggles Wilson, a Presbyterian Minister, and Janet Woodrow WilsonDied: February 3, 1924 in Washington, D.C.Education: Davidson College, Princeton University, University of Virginia, Johns Hopkins UniversityAwards and Honors: Nobel Peace PrizeSpouse(s): Ellen Axson (m. 1885–1914), Edith Bolling (m. 1915–1924)Children: Margaret, Jessie, Eleanor Early Life Thomas Woodrow Wilson was born on December 28, 1856, in Staunton, Virginia. He was the son of Joseph Ruggles Wilson, a Presbyterian Minister, and Janet Jessie Woodrow Wilson. He had two sisters and one brother. Shortly after Wilsons birth, his family soon moved to Augusta, Georgia, where Wilson was educated at home. In 1873, he went to Davidson College but soon dropped out due to health issues. He entered the College of New Jersey- now known as Princeton University- in 1875. Wilson graduated in 1879 and went on to study at the University of Virginia School of Law. He was admitted to the bar in 1882. Being a lawyer, however, was not to his liking, and Wilson soon returned to school with plans to become an educator. He eventually earned a Ph.D. from Johns Hopkins University in 1886. Marriage On June 23, 1885, Wilson married Ellen Louis Axson, the daughter of a Presbyterian minister. They would eventually have three daughters: Margaret Woodrow Wilson, Jessie Woodrow Wilson, and Eleanor Randolph Wilson. Career Wilson served as a professor at  Bryn Mawr College  from 1885 to 1888 and then as a professor of history at Wesleyan University from 1888 to 1890. Wilson then became a professor of political economy at Princeton. In 1902, he was appointed president of Princeton University, a post he held until 1910. In 1911, Wilson was elected governor of New Jersey. In this position, he made a name for himself by passing progressive reforms, including laws to reduce public corruption. Presidential Election of 1912 By 1912, Wilson had become a popular figure in progressive politics and actively campaigned for the Democratic Partys presidential nomination. After reaching out to other leaders in the party, Wilson was able to secure the nomination, with Indiana governor Thomas Marshall as the vice presidential nominee. Wilson was opposed not only by incumbent President  William Taft  but also by  Bull Moose  candidate  Theodore Roosevelt. The Republican Party was divided between Taft and Roosevelt, allowing Wilson to easily win the presidency with 42% of the vote. (Roosevelt received 27% of the vote and Taft garnered 23%.) Presidency One of the first events of Wilsons presidency was the passage of the Underwood Tariff. This reduced tariff rates from 41 to 27 percent. It also created the  first federal income tax  after the passage of the 16th Amendment. In 1913, the Federal Reserve Act created the Federal Reserve system to help deal with economic highs and lows. It provided banks with loans and helped smooth out business cycles. In 1914, the Clayton Anti-Trust Act was passed to  improve labor rights. The law created protections for important labor negotiating tactics such as strikes, pickets, and boycotts. During this time, a revolution was occurring in Mexico. In 1914,  Venustiano Carranza  took over the Mexican government. However,  Pancho Villa  held much of northern Mexico. When Villa crossed into the United States in 1916 and killed 17 Americans, Wilson sent 6,000 troops under  General John Pershing  to the area. Pershing pursued Villa into Mexico, upsetting the Mexican government and Carranza. World War I  began in 1914 when  Archduke Francis Ferdinand  was assassinated by a Serbian nationalist. Due to agreements made among  the European nations, many countries eventually joined the war. The  Central Powers- Germany, Austria-Hungary, Turkey, and Bulgaria- fought against the Allies, Britain, France, Russia, Italy, Japan, Portugal, China, and Greece. America initially remained neutral, and Wilson was renominated to run for the presidency in 1916 on the first ballot along with Marshall as his vice president. He was opposed by Republican Charles Evans Hughes. The Democrats used the slogan, He kept us out of war, as they campaigned for Wilson. Hughes had a lot of support, but Wilson ultimately won in a close election with 277 out of 534 electoral votes. In 1917, the United States entered World War I on the side of the Allies. Two reasons were the sinking of the British ship  Lusitania,  which killed 120 Americans, and the Zimmerman telegram, which revealed that Germany was trying to get an agreement with Mexico to form an alliance if the United States entered the war. Pershing led American troops into battle, helping defeat the Central Powers. An armistice was signed on November 11, 1918. The Treaty of Versailles, signed in 1919, blamed the war on Germany and demanded huge reparations. It also created a League of Nations. In the end, the U.S. Senate would not ratify the treaty and would never join the League. Death In 1921, Wilson retired in Washington, D.C. He was very sick. On February 3, 1924, he died of complications from a stroke. Legacy Woodrow Wilson played a huge role in determining if and when America would get involved in  World War I. He was an isolationist at heart who attempted to keep America out of the war. However, with the sinking of the Lusitania, the continued harassment of American ships by German submarines, and the release of the  Zimmerman Telegram, America would not be held back. Wilson fought for the creation of the  League of Nations  to help avert another world war; his efforts won him the 1919  Nobel Peace Prize. Sources Cooper, John Milton Jr.  Woodrow Wilson: a Biography. Random House, 2011.Maynard, W. Barksdale.  Woodrow Wilson: Princeton to the Presidency. Yale University Press, 2013.

Human Resources Management Assignment Example | Topics and Well Written Essays - 3750 words

Human Resources Management - Assignment Example Human Resources Management From the past quarter, the organization is facing problem in its course of work that is directly related to HRM. The problem pertaining in the organization is related to knowledge management. New recruitment has taken place in the organization, and the new employees are not able to perform up to the expectations of the company. A lot of complaints have been made against the company about which the company came to know from the feedbacks of the customers. The complaints were mostly related to the solutions, which the employees provide to the customers as the employees lacked training and knowledge to do so. In this paper, we will discuss the issues that are pertaining to the organization and give recommendation and action plan so that the organization can work in an efficient manner and achieve its desired goals. The issues of the organization are related to the HRM department as they are responsible for recruiting and training of the employees. Some changes in the policy of HRM must be made to overcome these problems. Fresh employees had hired by the organization few weeks ago. The company had faced many difficulties after hiring because the employees were not capable of giving quick response to the problems of consumers. The feedbacks of the consumers help in analyzing the problems. It was identified through inspection that human resource department is the area where the improvement is needed. Some mismanagement in the department of human resource management is creating the problems to the organization.

The Demonstration of Anthropomorphism using a range of 3D Animation Essay

The Demonstration of Anthropomorphism using a range of 3D Animation Techniques, Evaluating a Range of Tools, Techniques and Methods - Essay Example The revolution in computer technology relative to animation , has immensely changed the face of animation industry. This animation leads to the attribution of human characteristics to inanimate objects or nonhuman organisms and is generally referred to as called as Anthropomorphism. This anthropomorphism can be demonstrated through the use of various animation tools and techniques including the latest technique of 3D Animation. This project proposes to develop a greater understanding of anthropomorphism and how it is used in the field of animation, also a deeper understanding of how to animate realistic movements, and the steps taken to create animation that is of a professional standard. This leads to the discussion and understanding of a range of suitable techniques, tools and methods that can be employed in the production of such an artefact. All such efforts rely heavily on certain professional animation techniques that are used in portraying a believable message. Much of the concepts related to body language, movement and aesthetics are the controlling factors that instantiate anthropomorphism into a fictional character. To create life like characters , animators must create flawless human-like characteristics which demands thorough understanding of the movement and aesthetics of humans and how these characteristics effect peoples perception of these features. To bring about these effects there has to be a perfect story board design and various animation tools and techniques that render these effects. The important steps in producing a 3D animated shot or animated movie include preparation of digital story board, Modelling, Simulation, Rendering and post production special effects. The above mentioned steps could be accomplished with the aid of special software tools like Autodesk Maya , 3D Studio Max and other rendering and directing tools like Renderman , Diorama, etc. Based on

Three Phase Induction Motors Engineering Essay

Three Phase Induction Motors Engineering Essay Three phase induction motors are one of the most widely used industrial machines. This is mainly due to their simplicity, high reliability and robustness. Although three phase induction motors have the same physical stator as a synchronous machine, they do have different rotor constructions. In addition, three phase induction motors are divided into two groups: squirrel-cage and wound rotor. The magnitude of the flux in the quadrature axis in the stator diminishes, so that the flux will be zero, but the speed is increased above the synchronous speed. The rotor current comes from rotor voltage, so the resultant backward rotating for the flux component provides the magnetomotive force (mmf) so the flux is positive in the quadrature axis. So, the speed at which the magnetic field rotates can be determined. If the motor is connected to rated frequency, the speed of the magnetic field is called the synchronous speed (Ns). The following table shows the relationship between number of poles and synchronous speed when the frequency equals 50HZ. Pole pairs 1 2 3 4 6 Number of poles 2 4 6 8 12 Synchronous speed 3000 1500 1000 750 500 Table (3.1) relationship between number of poles and synchronous The relationship between number of poles and synchronous speed is inversely proportional. 3.2 Equivalent circuit of an induction motor. The per phase equivalent circuit is very important for induction motors and can be used to provide a great deal of understanding and prediction of performance of the induction motor in a stable state. The induction motor needs to provide for operation on the induction voltage and current in the rotor circuit from the stator circuit (transformer action); this is because the voltage and current in the rotor circuit of an induction motor is basically a transformer operation. So the equivalent circuit of the induction motor is similar to the equivalent circuit of the transformer. (In the transformer, primary like the stator in the induction motor, secondary in the transformer like the rotor in the induction motor. In an equivalent circuit per phase of an induction motor, as shown in figure (3.1), Rs and Rr are the stator and rotor winding resistance per phase. Ls and Lr are stator and rotor leakage inductance per phase. However, the aim of test and analysis is to be able to refer the rotor resistance and reactance to the stator circuit and thereby to drive an equivalent circuit referred to the stator. Figure (3.1) induction motor per-phase equivalent circuits. (3.1) (3.2) (3.3) (3.4) (3.5) (3.6) (3.7) (3.8) (3.9) (3.10) (3.11) (3.12) (3.13) In this circuit between a and b apply Thevenin Figure (3.3) Simplification of equivalent circuits of an induction motor Open Circuit voltage at ab (3.14) Short Circuit supply (3.15) (3.16) (3.17) (3.18) Maximum occurs: (3.19) (3.20) . 3.3 Overview on control of Induction motors. Induction motors with squirrel-cage motors are used in industry because the advantage of these types of motors is their relatively low cost and simple construction. Induction motors always work at a nearly constant speed. However, power electronic converts; it can work to vary the speed of an induction motor. The induction motor drives can be divided into groups based on their applications: (a) Adjustable-speed drive. One important application of this drive is in process control by controlling the speed of fans, compressors, pumps. (b) Servo drive: by means of sophisticated control, induction motors can be used as servo drives in computer peripherals, machine tools, and robotics [reference]. I would like to give a brief explanation of two methods that are used in the control of induction motors and I will go into more detail about these methods later. Vector control is a method of control of induction motors so the stator current is controlled in the field rotating reference using PWM inverter [Reference]. The rotor flux and stator flux linkages are represented by ÃŽÂ »ar (t) and ÃŽÂ »as(t) depends on the angle of the rotor Ó ¨m because the mutual inductance between the stator windings and rotor windings position is connected. However, the main reason for the q and d axis analysis in machines like the induction machines is to control them properly, for example: vector control [reference], the method of vector control of induction motor drives produces better dynamic performance than scalar control [reference]. The following block diagram shows the direct torque control system of an induction motor. Figure (3.4) shows direct torque control of induction motors. This alternative type of control of an induction motor is very simple and basic in terms of construction. It consists of a switch table, hysteresis controllers, flux estimator and torque. It is much easier to represent in a block diagram compared to the block diagram representing the vector control system due to the absence of coordinate transformation between the synchronous frame and stationary frame and also it does not need a pulse width. Direct torque control drives are controlled by the method of a close loop system without using a current regulation loop and are also related to use of a stationary d-q reference frame as well as having the d-axis aligned with the stator q axis. Moreover, the flux and torque are controlled by the stator voltage space vector defined in this reference frame[reference]. Scalar control is another method of control of induction motors and is also the first method of control before the vector control method. The advantage of this method is simple cont rol and ease of use. The motor drive is described by three factors: (a) frequency (b) voltage (c) parameters of the motor and its power supply [reference]. The scalar variable is strictly one represented by magnitude alone. This method uses either close loop or open loop control and any feedback loop such as that for speed. This use of scalar quantities gives the basic characteristics of satisfactory steady state behaviour, but poorly controlled transient response. 3.4 Description of the Induction motor drive Since a motor drive plays a big part in the control system, it is necessary to have some background information about it. In a typical induction motor drive, power electronic devices are used to operate AC motors at frequencies other than the supply one. It consists of two main sections, a controller to set the operating frequency and a three-phase inverter to generate the required sinusoidal three-phase system from a DC bus voltage. Therefore, an induction motor requires a variable-frequency three-phase source for variable speed operation by using a power converter system consisting of a rectifier connected to an inverter through a DC link. The next figure shows a block diagram of the power circuit of a typical variable-frequency induction motor drive. Figure (3.5) shows Variable-Frequency Induction Motor Drive The rectifier converts the power grid AC voltage into a fixed DC voltage. An LC filter to provide a smooth DC voltage, which is then applied to the inverter input, filters out the harmonics. 3.5 Induction Motor Control Methods 3.5.1 Vector control The vector control of induction motors has been widely used for high performance drives. There have been many studies developed and presented which allow an overview of vector control (reference). Many proposals for the theory of electric machines discuss using space vector control to represent sinusoidal distribution in the air gap and they also discuss types of control of ac drives including induction motor drives, permanent-magnet ac drives and switched reluctance drives (reference). Induction motor drives have performance control as the same high performance four-quadrant DC drive. In 1960 field-oriented control (FOC) was used in the area of induction motors, but in the past decades, induction motors have been controlled by using scalar control methods like the voltage/hertz. However, this manner is an old way used before vector control in the area of induction machines, but it was an easy method of controlling an induction motor (Reference). 3.5.1.2 Concept of vector control The concept of vector control of AC drives is related to a space phaser which provides a means of representing three phase variables in a machine, voltage, current and flux (Reference). Both flux and torque (DTC) are basically controlled by methods of closed loop; so are methods of control of an induction motor, using closed loop without current loop, similar to the conventional vector control drives (Reference). So the stator current will be utilizing transformation to the d q synchronize system and direct axis with the rotor flux space factor; therefore, the stator d q axis current is controlled dependently and the d q-axis for rotor flux will be zero. (3.21) The relationship between the stator current, rotor flux and electromagnetic are shown by this equation: (3.22) Where Is rotor flux linkage, Rr , Lr , Lr are rotor resistance, and Lm magnetizing inductance. (Reference). However, the space vector in the three phase inverter will produce eight output states [1 0 0] switch states, upper in switch phase is represented by à ¡ and b- is closed and c are open. The eight space vector represented by V0 [ 0 0 0] and V7 [ 1 1 1 ] are null and continuing six are of equal magnitude and arranged 600 part in space diagram as shown in figure. (Reference). Figure (3.6) shows witching voltage space vectors. 3.5.1.3 Control Characteristics Vector control has allowed the dynamic performance of AC drives so that they better DC drives; the flux and the torque can be controlled separately by using vector control producing components of the supply current. The terminal voltage cannot be directly monitored, but can be using the dc link voltage and switching function of the inverter supplying the motor. Currently, the drive dynamic is largely used with the inverter control of the stator current of the induction machines; this in turn is determined by the supply voltage and inductance of the machine. The main features of the direct torque control (DTC) are direct control of the torque and flux, and indirect main control of voltages and currents. This type of control has a number of advantages: sinusoidal stator current and reduced torque oscillations; excellent torque dynamics; and the main advantage of (DTC) direct torque control, absence of coordinate transformations which related to vector control implementations. However, in this type of control there are some disadvantages: possible problems during starting and low speed operation and also during change in torque command; it also requires flux and torque estimators (Reference). The vector control theory provides independent control between torque and flux; torque is controlled by the q-axis component of current if the flux is constant and oriented along the d-axis of the referred frame. The referred frame can be rotor flux-oriented control, stator flux-oriented control or air gap flux-oriented control. Thus, the phase angle and the modulus of the current or current vector have to be controlled. Figure 2.1(a), [Reference], shows the rotor angle  Ã‚ ±r with respect to the stator. Since the vector control is to be implemented in the rotor flux oriented reference frame, the induction machine is fixed in that reference frame by rotating the variable as appropriate. Figure (3.7) shows that the rotor flux reference frame rotates at speed (angle  Ã‚ ±e) with respect to the stator reference and the d-q axes are fixed to the rotor flux space phasor. This results in decoupling of the flux and torque which are separately controlled by stator direct-axis current i ds and quadrature-axis current iqs. [Reference] (B) Vector rotation Figure (3.7) (A) Rotor angle 3.5.2 Direct and Indirect Rotor Flux-Oriented Control The vector controls can be divided into two groups, indirect and direct, for the indirect (slip frequency controlled) and the direct (field oriented). The characteristics of these two controllers have been considered to be the same, but there are some differences between these methods. However, the direct control type is a modern control theory and also has high performance and it is more well-known than indirect control (Reference). In this two methods above are considered of voltage and current of a stator. The first method, indirect, is related to stator current control and the second method is related to stator voltage control. In both cases the system inputs are torque and flux reference which is required current values for isd and isq. Field oriented control to induction motor operation in a synchronously rotating d-q reference from that is aligned with one of the motor flux. So, control of the torque and flux is decoupled such as the d- axis component of the stator current and rotor flux magnitude and the q-axis component control , the output torque , where the ids stator current of d-axis component and is the rotor flux magnitude demand, so can be given in equation as (3.23) Where, Lm = magnetizing inductance. For the q-axis component of the stator current iqs, the torque demand as (T* em) so can be determined as the equation: (3.24) The d-axis of the synchronously rotating reference frame to be aligned with the rotor flux, the slip relation. (3.25) Direct rotor flux-oriented control (RFOC) has a control loop for flux where the measurement is performed using flux sensing coils (or Hall-effect devices) or by the flux model. In indirect rotor flux-oriented control (RFOC), the rotor flux angle is not measured but is estimated from the equivalent circuit model. One of the techniques for estimating the rotor flux angle ( Ã‚ ±e) is based on the slip relation, which requires measurement of the rotor speed () and slip frequency (). The slip frequency is dependant on rotor time constant ( Ã‚ ´r) and estimated rotor flux amplitude. This indicates that indirect methods are easier to implement since they do not require a flux model, but are less accurate. Nevertheless, if the model were perfect, the performance obtained would be identical to direct torque control. In [6], the relationships between direct and indirect approaches have been analyzed. It proves that they have the same control but have differences in coordinate of state va riable, the rotor flux and stator currents. A new indirect vector control with an observer has been presented which has the same characteristic as the conventional direct torque control. Figure (3.8) direct vector control Figure (3.9) indirect vector control 3.5.3 Scalar control method Scalar Control manner is related to AC machines and can use voltage fed-inverters. In addition, the scalar control is related to control of the magnitude of a variable only, also using of applications for constant voltage/hertz supply at the motor terminals are given constant air gap flux, so it could be that the stator voltage is dropped. (Reference) The scalar control methods are considered just for study state behaviour, but have poorly controlled transients. (Reference) This method applies to use in either close loop or open loop, and in any feedback loop such as that of speed. The scalar control method was basically developed for study state operation. However, it is a method also used in variable speed applications. (Reference) In this curve, the voltage and frequency are applied on the stator, therefore, when the supply frequency is constant, the speed will be constant, but the torque can be changing as the square of the applied voltage. I will give more details about scalar control in another chapter. 3.5.4 Comparison of vector control (VC) and scalar control (SC). Induction machines are widely used in various industries as prime workhorses to produce rotational motions and forces. However, the squirrel-cage type is a simple and rugged electrical machine with low cost and minimal maintenance; this is reason that the squirrel-cage types are most widely used in industrial electrical motors [reference]. With regard to the scalar control methods for an induction machine, only the motor model is considered for steady state and the scalar control methods are controlled based of the induction motor, but this method will not give good performance transients for an induction motor and it is also poor in terms of dynamics; but the vector control methods considered above are valid for transient conditions and the vector control will give a dynamic performance far superior to that of scalar control [reference]. The scalar control method to control an induction motor is simple to execute and easy to programme, but the vector control is related to the varyin g magnitude and phase alignment of the vector quantities of the motor. Moreover, the scalar control is related to the voltage per hearts v/f control and is usually used for low cost drives where high dynamic performance is not a key requirement. The applications include fans, blowers and pumps where the applied load is known. In this method, the form is simple, the control does not require any sensors and the control algorithm can be implemented in a relatively low performance microprocessor. Vector control is related to a mathematical model which deals with voltage, current, flux torque and the motor parameters. We can control the instantaneous stator currents, control the magnitude and position is. The following diagram shows a feedback control system for measuring currents. When the controller has a fast response then is vector can be imposed on the stator rapidly. Advantages and disadvantages of vector control and scalar control [reference] Method Advantages Disadvantages SC Simplest method of obtaining variable speed. Low cost and easy to implement solution. Is widely used. Is not as complicated as other control methods. Poor transient performance and poor dynamic. It cannot control torque directly. The transit response such as control is not fast. VC For those d component and q component are two decouple components can be independently controlled by passing through separate PI controller. This control method has an excellent torque and speed curve. It has excellent dynamic performance. Sensitive parameter variation use PI current regulators that decrease transient performance. Is more complicated than any other control method. Cannot control torque before transformation is done. Table (3.2) advantages and disadvantages of scalar control and vector control

Caferoma’s Marketing Manager Essay

In the last two years, caferoma’s share of the quality ground coffee market has declined by almost 30 % (see chart). there are several reason for this: brand loyalty: consumers have become less loyal to brands and more price conscious. they are willing to buy lower-priced coffee product. price: supermarket are selling, under their own label, similar products to caferoma at much lower prices. Copycat producto: competing products of italian-style ground coffee are selling at price 30 to 40% lower than caferoma Brand Image: the caferoma brand no longer seems to be exciting and up-to-date. Repositioning the products: change caferoma’s image to appeal to a different market segment. (which segment? what changes to taste, quality, packaging, logo labelling, distribution?) princing reduce the price by, say. 20% to 30% so that it is in the medium range of price. advertising develop a new advertising campà ¡ing to relaunch the brand. multiple brand: sell caferoma, with small changes to product, under different brand names at lower prices. own brand label product: allow supermarket to sell Caferoma under the supermarket own brand label’s. Continue to market the Caferoma brand at the same time. A new product: Bring out an instant coffee or decaffeinated product under the caferoma brand as soon as possible. Stretching the brand: Allow some makers of coffee equipament (cafetieres, percolators, coffee, machines, etc.) to use the caferoma brand on their goods, for a licensing fee. Claudia, Caferoma’s Marketing Manager, has some recent new from one of Caferoma’s biggest customers, Majestic Hotels, a major European hotels chain. She discusses the news with Caferoma’s Sales Director, Pietro. Listen to their conversation. how does this new inormation affect your decisions? writing write an e mail to Caferoma’s Managing Director, Mario Cumino. Summarise what action you agreed to take at the meeting to solve Caferoma’s problem Explain your reasons. task as members of PEFD’s marketing team, hold an informal meeting. consider the advantages and disadvantage of each solution. then decide what to do stop the decline in the product’s market share and to increase profits

French Silent Letters - Lettres Muettes