Six

Background Efficiency is a strong competition tool in businesses; it reduces the cost of production and leads to a more satisfy customers. On the other hand, satisfied customers are an increased business to an organization. When pondering of a system that can point out areas of inefficiency, Motorola, company in 1981 innovated a system called Six-Sigma. Six-sigma is a management tool that approaches management from a scientific angle.Advertising We will write a custom report sample on Six-sigma in Toyota Motor Corporation specifically for you for only $16.05 $11/page Learn More It analyses an entire organizations processes and by creating relationships and data analysis, the area with a deficit is recognized. Six-sigma is implemented in business to improve the efficiency and increase the productivity of the entire organization; when the system is implemented, it focuses on all areas in an organization to have a totality of good results in the organizatio n. Though when implemented is a project that undertakes a number of procedures, it is a continuous process that requires constant improvements and upgrading (Tennant, 2001) The motor vehicle industry is a competitive sector that is not only affected by the player in the industry but also by other external forces in the market. It is one of the industries affected largely by external environment like international trade, global environments and economies and the relationship among countries. Toyota is the world greatest motor vehicle producer and seller; the success of the company has been attributed to an effective processes management. According to the company’s corporate website, its success can be attributed to internal process efficiency and improved products. The process adopted by the company to improve its processes and produces in TQM (Total Quality Management) system. However, the company can improve its operation further and improve its products quality if it adopts a Six-sigma strategy in its operations (Hino, 2006). This paper is a case study of how Toyota Motor Corporation can implement a Six-sigma policy in its processes. Brief History of Toyota Motor Corporation Toyota is a multinational company found in Japan and it is the leading automobile carmakers and seller in the world; other than automobile business, the company offers financial services. It was incorporated in 1937; its founder is Kiichiro Toyoda. Currently, the company’s chairperson of board of directors is Fujio Cho and the Chief Executive Officer is Akio Toyoda, it has its global headquarters at Toyota, Aichi, Japan.Advertising Looking for report on business economics? Let's see if we can help you! Get your first paper with 15% OFF Learn More According to 2009, financial report, the company had employed 71116 directly and other people who indirectly benefit from the company were 259792 in the same year, distributed in 540 consolidated subsidiaries and 226 affiliates. The main market for the company is in North America followed by the home market: its competitors include Mitsubishi, Honda, General Motors and Ford. According to fortune global survey 500 of 2008, it was the fifth largest company in the world and the second largest automobile company. The company is structured in a no extra ordinary way and has departments like any other multinationals in the world; however, the achievement of the company has made it different in performance something that proves that something extra happens. In 2008, it was able to surpass General motor company as the world largest automobile seller in the world. What has made the company go this far? The answer is in the quality of its management and the interaction that brand as well the loyalty that it derives from its customers (see the appendixes for the company’s sales by region). To maintain the leadership role, the company needs to adopt a six-sigma mechanism of controlling different sec tors (Toyota Motor Company corporate website, 2011). The operating strategy of Toyota The company has a framework that works alongside. Operates under five principals, they are Kaizen (continuo’s improvement), team work, Challenges, Respect and Genchi Genbutsu (go and see). Toyota is divided into small teams with team leaders and given certain task that they are supposed to perform and improve accordingly. Innovation is seen as a necessity in the firm both the Japan head quarters and the rest of the subsidiaries. The effectiveness has been seen when the employees has innovated different products that supposed to abide to the general principals of the company. The combinations have lived to the task of continuously improving its processes to a point that it was able to surpass general motors. This is in line with the company’s principal of Kaizen.Advertising We will write a custom report sample on Six-sigma in Toyota Motor Corporation specifically for you for only $16.05 $11/page Learn More In the components statements it has an express statement that is adhered to that is â€Å"adding value to the organization by developing its people† as people are being developed and empowered, they are enthusiastic and come up with the innovations. The company employs people various level of competitiveness. On the other hand, they have their own training school called Toyota Technological Institute at Chicago that among other duties is used as the breeding ground of the employees. It has a policy that enables graduates of different diversities relevant to the particular task to join the company and grow in the company. They also recruit from all over the world. This efficiency is what has made the company such a success, especially in the areas of innovation. In the institution, it offers scholarships to people with potential especially in the motor and designing of motor vehicle this are deliberate measures that are aimed at continuously improving it processes. The technology adopted by the company can be seen from two angles. One in the marketing strategies and two in the continuous improvement of its processes when the company was set up in 1937, it is obvious that the technological advancement has been attained in the entire world. There is a research department that has the aim of undertaking the policy of Genchi Genbutsu (go and see). The company’s first car was a high fuel consuming passenger car called A1 and G1. The vehicles were manually modeled. Today the numerous models in the market are because of computer-aided modeling. All along, we are hearing of Toyota X new model. This shows how they are continually improved their products to remain competitive in the world (Toyota Motor Company corporate website, 2011). Major challenges facing the company that can be improved using Six-sigma system The world is recovering from global financial crisis which started in 2007, the company was a ffected by the crisis and recorded a loss of US$4.2 billion; although the crisis were beyond what the company could control, then if the company had an effective six-sigma policy, then it would have reduced the loss suffered. The next area that the company is facing inefficiency is in faulty automobiles finding their way into the market; between the last quarter of 2009 and first quarter of 2010, the company recalled some faulty cars from different markets to the tune of 8million cars and trucks.Advertising Looking for report on business economics? Let's see if we can help you! Get your first paper with 15% OFF Learn More Due to the recall the United States Congress committees on Oversight and Investigations, seek for explanation on the recall of the country from James Lentz the US Sales Chief; it ended by the company being fined US$16.375 million for the faulty products. In the year ended 31 March 2010, the company recorded that it had suffered a total loss of US$1.93 billion ( ¥180 billion). This loss could have been avoided if the company had an effective Six-sigma policy (Toyota Motor Company corporate website, 2011). Of late, the automobile industry has been affected by changes in environmental policies that are focusing and targeting the industry to ensure that its processes as well as products are environmentally friendly. The company has to company with international standards of pollution emissions; to keep the trend, the company need to increase efficiency in its operations. To remain competitive in the industry, companies in the industry need to improve their internal processes and produ cts. When developing internal process and products improvements, focus is given to all sectors of the company. The industry can have its sectors being divided into administrative and the core line of business, both the sectors should be focused in to have a total improvement of processes and projects (Pyzdek and Paul, 2009). Implementation of Six-Sigma in Toyota Generally, there are six stages of six-sigma that Toyota should implement for the start of the project; then the processes are improved with time and as new policies and dimensions are implemented. The word DMAIC (the acronym for Define, Measure, Analyze, Improve and Control), is used to define the processes that are involved in an effective six sigma operation. Define The automobile industry is facing numerous challenges; Toyota having assumed the leadership in the industry does not guarantee that it will retain the position for the rest of its life. The managers should define the current position and so as it can understan ds business conflicts and business problems the company is undergoing through or the company is likely to undergo through in the future. Understanding a problem encountered in an organization is the first step in developing a solution and develop methodology or combination of methodologies, to solve the business problem at hand. When defining a problem, the managers should use the symptoms or indicators of inefficiency to get to the root course: Six sigma projects should target the root causes and not the symptoms (Snee and Hoerl, 2002). To diagnose a problem, two questions that should be used as the start point, they are: What exactly is the current problem facing the organization for example the quality of its vehicles or the environmentally friendly vehicles? Which areas are affected by the problem and how has this problem affected the operation of the entire organization; is the problem leading to losses? With the full understanding of the problem, then the company adopts a pr oject plan or a team charter; there are different methods of adopting the project plan or a team charter, they include CTQ, (Customer to Quality) among others, the best method will be defined by the problem at hard. The plan adopted should be used to improve all sectors in the organization for examples, marketing, sales and finance (Pande, Neuman and Cavanagh, 2001). Measure At this stage, the Toyota management should find and gather as much information as possibly available to develop different solutions and alternatives (O’Connor, 1989). Generally there are three processes involved in the measure stage, they are: Value Stream Mapping: this involves having a clear analysis of the problem and the project at hand: at the stage the company should aim at analysis the difference between what is expected (the firms goals and objectives) and what the company is really giving. It seeks to establish the missing points, waste areas, areas of inefficiencies, and constraints to achievem ent of the corporate goals. Toyota should have an understanding of the quality of its processes and the products so as it can realize the differences between them. Data Gathering: With the gaps and areas, that needs improvement at hand, and then the management should seek to develop alternatives of solutions so it can choose the best out of the list available. To gather information, the management should adopt five Ws strategy (when, what, who, where and why). Information should be vetted for relevance and applicability in certain areas (Mà ¼nsterberg, 1973). Data measurement validation: with the data at hand, then the management should adopt data management, interpolation and analysis methodologies: some of the tools used are Gauge RR), control charts, time plots or Pareto charts. The main concern of this stage that the company should have is to understand â€Å"where it is† and where it â€Å"should be†, then the difference between the two is the area of focus in th e six sigma policy. Analyze At this stage, the management has reliable information about the problem or areas of potential problem the information should be analyzed to get the root cause of the problems. Cause and Effect Analysis, FMAE (Failure modes and effects), Correlation and regression studies and DOE (design of experiments). This stage marked the project more focused on particular key areas. The areas of concerns have been recognized and the alternatives that the company has known; the best alternative will be the one that will yield expected results in the least time using minimum resources (Keller, 2001). Implement Now the management/implementation team understands the problem at hand, has a well-defined picture of what is going on in an organization, understand departments with inefficiencies and the financial implications of the gaps (Wheelen and Hunger, 1998). The next step is to devise a number of possible solutions to be implemented. Here staffs should be fully include d. Alternatives are derived and the best alternative among the many is considered. After the alternative has been chosen, then there is support from all corners, these will involve management offering direct support to departments in attaining their new set goals. Many are the times that need for frequent meeting at departmental level or the entire company is important to discuss any issue that night has cropped up during the implementation. Periods are important in this stage to ensure that the new goals set attainability is possible. There are times that a short time evaluation for example weekly recording can be made to measure progress of the project. At this level, there is use of Force field diagram, Stakeholder Definition, and FAME to explain progress (Taylor, 2008). Control After implementation of the policy: Toyota Management at different regional offices should develop a control and monitoring team. When controlling there is an already set path, through which processes sho uld follow. They should start from somewhere heading to another area. When under control, there is need to have a well-defined personnel’s who have been recognized to have a certain efficiency level in an area, they should be empowered to conduct their duties. If there was a department that was scrapped, then any effects as a result should be understood and addressed effectively. When controlling and monitoring, managers should establish areas that need improvement should be pointed out, and appropriate actions taken accordingly (Adams, Gupta and Charles, 2003). The implications of a Six-sigma strategy in Toyota After the implementation of the strategy, the company will recognize areas of deficiency and inefficiency, and device appropriate measures to improve their operations. When using the Six-sigma strategy, then routes of efficiency will be developed which lay-down steps that must be followed. The steps are regarded as the path of efficiency; when the company is following these routes, it will benefit from low operating costs and improved products quality. Six-sigma policy consists of competitive moves and business approaches aimed at producing successful performance; it is management’s â€Å"game plan† for running the business, strengthening a firm’s competitive position, satisfying the customers, the stakeholders, share holders and the staffs. It seeks to develop the way into which all those that are a party to the business get satisfied. It aims at going a step further and satisfying the customers beyond their expectations. When the system is fully operation in Toyota, the company is likely to face the world automobile market more rejuvenated and have products that are more competitive. References Adams, W., Gupta, P. and Charles, E. ,2003. Six Sigma Deployment. Burlington, MA: Butterworth-Heinemann. Hino, S.,2006. Inside the mind of Toyota: management principles for enduring growth. Tokyo: Productivity Press. Keller, A. ,200 1. Six Sigma Deployment: A Guide for Implementing Six Sigma in Your Organization. Tucson, AZ: Quality Publishing. Mà ¼nsterberg, H.,1973. Psychology and Industrial Efficiency. New York: Arno Press. O’Connor, P.,1989. Total Quality Management (Book). Quality Reliability Engineering International. April 1989; 5(2),p.183. Pande, S., Neuman, P. and Cavanagh, R. ,2001. The Six Sigma Way: How GE, Motorola, and Other Top Companies are Honing Their Performance. New York, NY: McGraw-Hill Professional. Pyzdek, T. and Paul A. ,2009. The Six Sigma Handbook, Third Edition. New York, NY: McGraw-Hill. Snee, D. and Hoerl, W.,2002. Leading Six Sigma: A Step-by-Step Guide Based on Experience with GE and Other Six Sigma Companies. Upper Saddle River, NJ: FT Press. Taylor, G.,2008. Lean Six Sigma Service Excellence: A Guide to Green Belt Certification and Bottom Line Improvement. New York, NY: J. Ross Publishing. Tennant, G.,2001. SIX SIGMA: SPC and TQM in Manufacturing and Services. Aldershot , UK: Gower Publishing, Ltd. Toyota Motor Company corporate website. (2010). Toyota. Available at  https://www.toyota.com/ [acccessed 20th March 2010] Wheelen, L. and Hunger, J.,1998. Strategic Management and Business Policy: Entering 21st Century Global Society. Massachusetts: Addison Wesley. This report on Six-sigma in Toyota Motor Corporation was written and submitted by user Aniyah Kirby 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.

Snyder v Phelps Essays

Snyder v Phelps Essays Snyder v Phelps Essay Snyder v Phelps Essay Everyone is entitled to pattern their faith. Everyone has the right to voice their sentiment. The measure of rights provinces that this right could neer be taken off. but does it do it right for a individual to utilize this right to assail a individual? On March 3rd. 2006 a Marine. Lance Corporal Matthew Snyder. died of hurts sustained in a vehicle accident in Anbar state. Iraq. A hebdomad subsequently a funeral service was held in award of this fallen soldier in his hometown of Finksburg. Maryland. As the service began an accretion of people began to piece to riot with marks that say. Thank God for Dead Soldiers. The beginning of this disturbance all comes from the presence of one adult male and his fold. Pastor Fred Phelps and the Westboro Baptist church of Topeka. Kansas. The Westboro church’s actions all stemmed from Phelps and the church’s belief that God is penalizing the United States for leting homophiles into the military. although Lance Corporal Snyder was non homosexual. in fact. Phelps claims he was non aiming the household of the deceased but alternatively was aiming the U. S. Military. merely utilizing Snyder’s funeral as a forum for their protest. These actions carried on by the Westboro Baptist church are nil new to the populace ; the fold has made several visual aspects at funerals since 1955 doing major contentions throughout the universe. but Albert Snyder. the male parent of the asleep Marine decided to take legal action against the wrongdoers. by actioning the church. its Curate and his two girls. Cursing to the public Snyder stated that he wasn’t making it for the money. but wanted to hush the group. Snyder besides stated he was contending to protect the other households emotionally torn from the hurting inflicted by the Westboro church. as he himself felt his son’s memory was disrespected and privateness was evaded on. On February 4th 2008 the instance went to a District degree Court in Maryland which Judge Bennet ruled in favour of Snyder presenting him from a reduced five million dollars by using both federal constitutional and province common jurisprudence criterions to 2. million dollars emotional amendss caused by the church. Three yearss subsequently Phelps filed a statement to the Court of Appeals in the Fourth District On September 24th 2009. the appellant tribunal ruled in Phelps’s favour. siding with his right to pattern freedom of address and faith no affair how hideous. had been protected by the First Amendment. Snyder statement had besides been eakened because he did non really see the protest except for on telecasting. He didn’t even cognize it was traveling on until after the funeral already ended and had returned to his place and viewed it on the intelligence. Bing that both parties are reasoning from different provinces. the United States Supreme Court had to acquire involved. On March 2nd. 2011 The Supreme Court in an 8 to 1 decided. as did the Appellate tribunal sided with Phelps and his fold. The make up ones minding item the caused the determination was Phelps’s protest happening on a public pavement. and is speaking about issue that is good known to the populace. can non be held responsible for the emotional hurt that occurs as a consequence. had Snyder had been in position of Phelps’s protest he would hold been saw as an unwilling hearer to the hateful discourse. Catching up with Albert Snyder after the determination. he states. It’s over and he’s ready to travel on Snyder merely regrets non decently happening closing to son decease after contending a legal war for five old ages the Fred Phelps and his Party.

Analysis And Usage Of Cams And Their Followers Engineering Essay

Analysis And Usage Of Cams And Their Followers Engineering Essay A cam follower, also known as a track follower,[1] is a specialized type of roller or needle bearing designed to follow cams. Cam followers come in a vast array of different configurations, however the most defining characteristic is how the cam follower mounts to its mating part; stud style cam followers use a stud while the yoke style has a hole through the middle.[2] The first cam follower was invented and patented in 1937 by Thomas L. Robinson of the McGill Manufacturing Company.[3] It replaced using just a standard bearing and bolt. The new cam followers were easier to use because the stud was already included and they could also handle higher loads.[ / CAM AND MECHANISMS A cam mechanism consists of three elements: the cam, the follower (or follower system), and the frame. The follower is in direct contact with the cam. The cam may be of various shapes. The follower system includes all of the elements to which motion is imparted by the cam. This may be connected directly to the follower, or connected through linkages and gearing. The frame of the machine supports the bearing surfaces for the cam and for the follower. A CAM changes the input motion, which is usually rotary motion (a rotating motion), to a reciprocating motion of the follower. They are found in many machines and toys WHAT IS THE CONCEPT BEHIND CAM? A CAM is a rotating machine element which gives reciprocating or oscillating motion to another element known as follower. The cam and follower has a point or line contact constitute a higher pair or you can say that it is the mechanicl component of a machine that is used to transmit the motion to the another component of the machine called the follower, through a prescribed program by direct contact.The contact between them is maintained by an external force which is generally provided by the spring or sometimes by the weight of the follower itself ,when it is sufficient. Cam is the driver member and the follower is the driven member. The followe r is in direct contact with the cam. CAM MECHANISM CONSIST OF THREE MECHANISMS CAM:It may be of many shapes FOLLOWER: It includes all the elements to which motion is imparted by the cam.This may be connected directly by the cam.This may be connected directly to the follower, or connected through linkages and gearing. FRAME: The frame of the machine supports the bearing surfaces for the cam and for the follower. APPLICATIONS OF CAM AND FOLLOWERS Cam and follower are widely used for operating inlet and exhaust valve of I C engine. These are used in wall clock. These are used in feed mechanism of automatic lathe Machine. These are used in paper cutting machine. Used in weaving textile machineries. The cam mechanism is a versatile one. It can be designed to produce almost unlimited types of motioning the follower. It is used to transform a rotary motion into a translating or oscillating motion. On certain occasions, it is also used to transform one translating or oscillating motion into a different translating or oscillating motion.

Convinving a friend to stop smoking Essay Example | Topics and Well Written Essays - 500 words

Convinving a friend to stop smoking - Essay Example Wouldn't it be wonderful for you to quit smoking Imagine the improved health, physically and mentally not to mention the extra savings from cigarettes expenses each week. Allow me to show you why you need to stop smoking. The American Heart Association (AHA) in their recent survey indicates that smokers live an average of 14 years less than smokers (Marrow, 2008). There are many reasons for this, one of them being the diseases associated with smoking. Health authorities usually puts a warning on each cigarette box against the would be smokers but I think you need more than this. Listen to this from think.quest.org estimates that over 3000 chemical substances exist in tobacco smoke. Nicotine, carbon monoxide, sulpher dioxide, methanol are just a few. Assuming now somebody comes to you and says "hey you want to inject a dose of sulpher dioxide in your blood stream." Would you deny it Yet that is what you are doing each time you smoke. Diseases such as lung cancer, cardiovascular diseases, pulmonary diseases, asthma, osteoporosis, smokers cough, cancers of lynx and tongue are derived from such chemicals, and the risk is directly proportional to the cigarettes smoked. Apart from the diseases other condit ions can be foul body odor and general ill feeling (Marrow, 2008). So how do you exactly stop smoking Firstly sit down and write a list of thing that compels you to stop smoking then set a date for the action.

Classic Airlines Marketing Solution Essay Example | Topics and Well Written Essays - 1500 words

Classic Airlines Marketing Solution - Essay Example This is irrespective of a manager’s educational background or their intellectual abilities as problem solving is a nurtured skill. Problems are a part of a business’s routine that helps it to grow. For instance, the objective of this paper will be to solve classic airlines marketing problem using the nine-step model by identifying and defining the problem. Additionally, it will tackle the objectives and obstacles available in the solving of the marketing problem of the airlines marketing department. Issues identification within Classic Airlines Classic airline is the world fifth largest airline with three hundred and seventy five jets in its stable. It has over two hundred and forty flight destinations with at least two--thousand three hundred flights in a day. Its existence is over twenty-five years, which has seen the company grow to having a total number of thirty two thousand employees. Its average turnover per year is between ten million and nine billion. Like any other business structure, Classic Airlines has had its part of challenges. The company witnessed intense plummet of its share price in the stock market because of flying uncertainties. In addition, the negative publicity exhibited by the public, the media and the Wall Street market have gravely affected employee morale hence affecting their overall performance. Problem statement In effect, the consumer confidence on the airline dwindled as the Classic customer reward program membership decreased by an alarming number. The number of flying times that the remaining Classic loyal customers reduced significantly over a short period. Some of the customers jumped ship to access services from the airlines competitors. Moreover, Classic Airline’s inability to meet the rising fuel and labor costs have made the airline unable to compete in a well represented market. In a counter approach move, the airline’s board of directors suggested a cost reduction measure for a period range of one and half years. Under the set period, Classic airline would be able to beef up its frequent flier programs that should bring a significant return on investment. SWOT analysis for the company Strengths Weaknesses Opportunities Threats Long time existence in the market Regular flight delays Investing on the changing customer needs Fierce competition from other players within the travel industry Internationally recognized brand The number of seats that a customer has to have for them to redeem their flier miles The recovery of the travelling industry Fluctuating global currency rates Customer loyalty to frequent flier programs Carelessness of staff leading to loss of client luggage The airlines’ good reputation with the labor unions High fuel and equipment costs Effective implementation of cost reduction measures Poor inter client and staff relationship Venturing in to new destinations both internationally and locally Sanctions imposed by the European Union on carbon emi ssions and the environment Good relations with its employees Reliance to old forms of travelling techniques Steps in problem solving for Classic Airline’s marketing problem Short-term issues Classic Airlines’ service product Ideally, the greatest, selling point of a product or service is the service product itself. In essence, a service is the act of approaching a need or want in an intangible manner where no one claims ownership.

APJ Abdul Kalam Essay Example for Free

APJ Abdul Kalam Essay Introduction A savanna, or savannah, is a grassland ecosystem characterized by the trees being sufficiently widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to support an unbroken herbaceous layer consisting primarily of grasses.[1][2][3] The oak savanna is a common type of savanna in the Northern Hemisphere. Some classification systems[which?] also recognize a grassland savanna from which trees are absent.[4] This article deals only with savanna under the common definition of a grassy woodland with a significant woody plant component. It is often believed that savannas feature widely spaced, scattered trees. However, in many savannas, tree densities are higher and trees are more regularly spaced than in forest. Savannas are also characterized by seasonal water availability, with the majority of rainfall confined to one season. Savannas are associated with several types of biomes. Savannas are frequently in a transitional zone between forest and desert or grassland. Savanna covers approximately 20% of the Earths land area. Etymology Cerrado savanna, Brazil. Although the term savanna is believed to have originally come from an Arawak word describing land which is without trees but with much grass either tall or short (Oviedo y Valdes, 1535), by the late 1800s it was used to mean land with both grass and trees. It now refers to land with grass and either scattered trees or an open canopy of trees. Spanish explorers familiar with the term sabana called the grasslands they found around the Orinoco River llanos, as well as calling Venezuelan and Colombian grasslands by that specific term. Cerrado was used on the higher savannas of the Brazilian Central Plateau. Distribution Many grassy landscapes and mixed communities of trees, shrubs, and grasses were described as savanna before the middle of the 19th century, when the concept of a tropical savanna climate became established. The Kà ¶ppen climate classification system was strongly influenced by effects of temperature and precipitation upon tree growth, and his oversimplified assumptions resulted in a tropical savanna classification concept which resulted in it being considered as a climatic climax formation. The common usage meaning to describe vegetation now conflicts with a simplified yet widespread climatic concept meaning. The divergence has sometimes caused areas such as extensive savannas north and south of the Congo and Amazon Rivers to be excluded from mapped savanna categories.[5] Barrens has been used almost interchangeably with savanna in different parts of North America. Sometimes midwestern savanna were described as grassland with trees. Different authors have defined the lower limits of savanna tree coverage as 5–10% and upper limits range as 25–80% of an area.[6] Two factors common to all savanna environments are rainfall variations from year to year, and dry season wildfires. In the Americas, e.g. in Belize, Central America, savanna vegetation is similar from Mexico to South America and to the Caribbean. Threats Changes in fire management Savannas are subject to regular wildfires and the ecosystem appears to be the result of human use of fire. For example, Native Americans created the Pre-Columbian savannas of North America by periodically burning where fire-resistant plants were the dominant species.[8] Pine barrens in scattered locations from New Jersey to coastal New England are remnants of these savannas. Aboriginal burning appears to have been responsible for the widespread occurrence of savanna in tropical Australia and New Guinea,[9] and savannas in India are a result of human fire use.[10] The maquis shrub savannas of the Mediterranean region were likewise created and maintained by anthropogenic fire.[11] Prescribed burn; Wisconsin bur oak savanna These fires are usually confined to the herbaceous layer and do little long term damage to mature trees. However, these fires either kill or suppress  tree seedlings, thus preventing the establishment of a continuous tree canopy which would prevent further grass growth. Prior to European settlement aboriginal land use practices, including fire, influenced vegetation[12] and may have maintained and modified savanna flora.[3][9] It has been suggested by many authors[12][13] that aboriginal burning created a structurally more open savanna landscape. Aboriginal burning certainly created a habitat mosaic that probably increased biodiversity and changed the structure of woodlands and geographic range of numerous woodland species.[9][12] It has been suggested by many authors[13][14] that with the removal or alteration of traditional burning regimes many savannas are being replaced by forest and shrub thickets with little herbaceous layer. The consumption of herbage by introduced grazers in savanna woodlands has led to a reduction in the amount of fuel available for burning and resulted in fewer and cooler fires.[15] The introduction of exotic pasture legumes has also led to a reduction in the need to burn to produce a flush of green growth because legumes retain high nutrient levels throughout the year, and because fires can have a negative impact on legume populations which causes a reluctance to burn.[16] Grazing and browsing animals Oak savanna, United States The closed forest types such as broadleaf forests and rainforests are usually not grazed owing to the closed structure precluding grass growth, and hence offering little opportunity for grazing.[17] In contrast the open structure of savannas allows the growth of a herbaceous layer and are commonly used for grazing domestic livestock.[18] As a result much of the worlds savannas have undergone change as a result of grazing by sheep, goats and cattle, ranging from changes in pasture composition to woody weed encroachment.[19] The removal of grass by grazing affects the woody plant component of woodland systems in two major ways. Grasses compete with woody plants for water in the topsoil and removal by grazing reduces this competitive effect, potentially boosting tree growth. In addition to this effect, the removal of fuel reduces both the intensity and the frequency of fires which  may control woody plant species.[21] Grazing animals can have a more direct effect on woody plants by the browsing of palatable woody species. There is evidence that unpalatable woody plants have increased under grazing in savannas.[22] Grazing also promotes the spread of weeds in savannas by the removal or reduction of the plants which would normally compete with potential weeds and hinder establishment.[12] In addition to this, cattle and horses are implicated in the spread of the seeds of weed species such as Prickly Acacia (Acacia nilotica) and Stylo (Stylosanthes spp.).[15] Alterations in savanna species composition brought about by grazing can alter ecosystem function, and are exacerbated by overgrazing and poor land management practices. Introduced grazing animals can also affect soil condition through physical compaction and break-up of the soil caused by the hooves of animals and through the erosion effects caused by the removal of protective plant cover. Such effects are most likely to occur on land subjected to repeated and heavy grazing.[23] The effects of overstocking are often worst on soils of low fertility and in low rainfall areas below 500 mm, as most soil nutrients in these areas tend to be concentrated in the surface so any movement of soils can lead to severe degradation. Alteration in soil structure and nutrient levels affects the establishment, growth and survival of plant species and in turn can lead to a change in woodland structure and composition. Tree clearing Large areas of Australian and South American savannas have been cleared of trees, and this clearing is continuing today. For example until recently 480,000 ha of savanna were cleared annually in Australia alone primarily to improve pasture production.[12] Substantial savanna areas have been cleared of woody vegetation and much of the area that remains today is vegetation that has been disturbed by either clearing or thinning at some point in the past. Clearing is carried out by the grazing industry in an attempt to increase the quality and quantity of feed available for stock and to improve the management of livestock. The removal of trees from savanna land removes the competition for water from the grasses present, and can lead to a two to fourfold increase in pasture production, as well as improving the quality of the feed available.[24] Since stock carrying capacity is strongly correlated  with herbage yield, there can be major financial benefits from the removal of trees,[25] such as assisting with grazing management: regions of dense tree and shrub cover harbors predators, leading to increased stock losses, for example,[26] while woody plant cover hinders mustering in both sheep and cattle areas.[27] A number of techniques have been employed to clear or kill woody plants in savannas. Early pastoralists used felling and girdling, the removal of a ring of bark and sapwood, as a means of clearing land.[28] In the 1950s arboricides suitable for stem injection were developed. War-surplus heavy machinery was made available, and these were used for either pushing timber, or for pulling using a chain and ball strung between two machines. These two new methods of timber control, along with the introduction and widespread adoption of several new pasture grasses and legumes promoted a resurgence in tree clearing. The 1980s also saw the release of soil-applied arboricides, notably tebuthiuron, that could be utilized without cutting and injecting each individual tree. In many ways artificial clearing, particularly pulling, mimics the effects of fire and, in savannas adapted to regeneration after fire as most Queensland savannas are, there is a similar response to that after fire.[29] Tree clearing in many savanna communities, although causing a dramatic reduction in basal area and canopy cover, often leaves a high percentage of woody plants alive either as seedlings too small to be affected or as plants capable of re-sprouting from lignotubers and broken stumps. A population of woody plants equal to half or more of the original number often remains following pulling of eucalypt communities, even if all the trees over 5 metres are uprooted completely. Exotic plant species Acacia savanna, Taita Hills Wildlife Sanctuary, Kenya. A number of exotic plants species have been introduced to the savannas around the world. Amongst the woody plant species are serious environmental weeds such as Prickly Acacia (Acacia nilotica), Rubbervine (Cryptostegia grandiflora), Mesquite (Prosopis spp.), Lantana (Lantana camara and L. montevidensis) and Prickly Pear (Opuntia spp.) A range of herbaceous species have also been introduced to these woodlands, either deliberately or accidentally including Rhodes grass and other Chloris species, Buffel grass (Cenchrus ciliaris), Giant rats tail grass (Sporobolus pyramidalis)  parthenium (Parthenium hysterophorus) and stylos (Stylosanthes spp.) and other legumes. These introductions have the potential to significantly alter the structure and composition of savannas worldwide, and have already done so in many areas through a number of processes including altering the fire regime, increasing grazing pressure, competing with native vegetation and occupying previously vacant ecological n iches.[29][30] Other plant species include: white sage, spotted cactus, cotton seed, rosemary. Climate change There exists the possibility that human induced climate change in the form of the greenhouse effect may result in an alteration of the structure and function of savannas. Some authors[31] have suggested that savannas and grasslands may become even more susceptible to woody plant encroachment as a result of greenhouse induced climate change. However, a recent case described a savanna increasing its range at the expense of forest in response to climate variation, and potential exists for similar rapid, dramatic shifts in vegetation distribution as a result of global climate change, particularly at ecotones such as savannas so often represent.[32] Savanna ecoregions Mediterranean savanna in Alentejo region, Portugal. Savanna ecoregions are of several different types: Tropical and subtropical savannas are classified with tropical and subtropical grasslands and shrublands as the tropical and subtropical grasslands, savannas, and shrublands biome. The savannas of Africa, including the Serengeti, famous for its wildlife, are typical of this type. The Brazilian savanna (Cerrado) is also included in this category, known for its exotic and varied flora. Temperate savannas are mid-latitude savannas with wetter summers and drier winters. They are classified with temperate savannas and shrublands as the temperate grasslands, savannas, and shrublands biome, that for example cover much of the Great Plains of the United States. (See areas such as the Central forest-grasslands transition). Mediterranean savannas are mid-latitude savannas in Mediterranean climate regions, with mild, rainy winters and hot, dry summers, part of the  Mediterranean forests, woodlands, and scrub biome. The oak tree savannas of California, part of the California chaparral and woodlands ecoregion, fall into this category. Flooded savannas are savannas that are flooded seasonally or year-round. They are classified with flooded savannas as the flooded grasslands and savannas biome, which occurs mostly in the tropics and subtropics. Montane savannas are high-altitude savannas, located in a few spots around the worlds high mountain regions, part of the montane grasslands and shrublands biome. The lowland savannas of the Angolan Scarp savanna and woodlands ecoregion are an example.

Technology is the Solution to Overpopulation Essay -- Environment Envi

Technology is the Solution to Overpopulation About ten years ago while in a science museum, I saw a counter that estimated what the world population was at that given moment. Innocuous at first glance, since a number in excess of five billion is difficult to comprehend, what became alarming after watching the counter for a minute was the continual increase in the population. Thinking about the circumstances related to the population rise logically made the problem seem apparent. The earth is finite both in terms of physical size and in resources but the population is growing towards an infinite value. At some point the steadily rising population will move from being a problem that is geographically distant to one that is immediate and more salient than just an increasing value on a faceless counter. This problem of population growth leads to a number of solutions that could have significant implications on the quality of life. Taking no action and allowing population to grow unchecked could possibly risk the entire human species if food or clean water were to become unavailable worldwide. Aiming for zero population growth would in theory maintain the existing quality of life since a stable population would not increase their use of resources. However not all resources are renewable, so scarcities could still occur with a fixed population size. In an extreme case permanent resource depletion under zero population growth could have the same extinction effect that unchecked growth can lead to. Despite the escalating risk of unchecked population growth, technological advances necessitated by the increase in population will at least maintain the quality of life and could possibly improve conditions. Southwick in â€Å"Global Ecol... ...ould accept the fact that not all people of the world will be able to have a high standard of living but the potential for improved quality exists. This potential cannot be reached immediately since resources and population remain geographically separate and faster transportation would increase the spread of fatal diseases. Improvements in resource production such as increased crop yields makes it possible to support higher populations and improve the quality of life at least at a local level. References Southwick, C. H. Global Ecology in Human Perspective, Chapter 15. Oxford Univ. Press. (1996). World Health Organization â€Å"Frequently Asked Questions on Severe Acute Respiratory Syndrome (SARS),† Communicable Disease Surveillance & Response (CSR), March 24. (2003). World Health Organization . Retrieved March 29, 2004.

Our Time Essay

In Mary Louise Pratt’s essay, â€Å"Arts of the Contact Zone,† we are introduced to the idea of contact zones, autoethnography, and new ways of looking at common ideas. I wanted to see some examples of what she was really talking about. After reading John Edgar Wideman’s â€Å"Our Time† we can see that Pratt’s ideas and terms are accurate because they can be applied to this reading as well as others. â€Å"Our Time† is an autoethnography because it uses diffeerent points of view, not just oneself, to give information about someone’s upbringing and cultural growth. In Pratt’s essay, she often referred to the term autoethnography. These emerge from contact zones. Autoethnographies are used as a method to oppose the views of oneself that everyone else sees. For example, if there are people in your neighborhood that have a label on your home and family, you might go back and tell them how your life actually is. Mary Louise Pratt goes on to tell us that a contact zone is a place where people from different cultures and communities come together. Here, these different people share ideas and interact with each other. It is almost a type of hybridization. Multiple cultures or societies come together, and mash. They can join together, or exchange some values, or be overrun by one another. Within these contact zones, people are able to see the way others see them and interpret them. From there, they would be able to see themselves through different eyes, and from a different perspective. In relation, autoethnographic texts are â€Å"texts in which people undertake to describe themselves in ways that engage with repre sentations others have made of them† (Pratt 487). They are not texts written to Bolduc 2 explain how the writer sees themselves, but how they are seen by others. This is to maximize the credibility, and that there isn’t too much bias. Writers put together these texts from others’ understandings and viewpoints of them, as well as interpretation of others. Similarly, Pratt also refers to the term transculturation frequently in her essay. The definition of transculturation is when values or ways of life and habits from the dominant culture are passed down to smaller subordinate cultures. From there, those cultures choose what materials they would like to use as well as trying to  persuade the dominant culture to use some of their ideas. In Pratt’s essay, she uses Guaman Poma’s New Chronicle to back up her claims. She refers to the reading as an autoethnographic text. This text â€Å"involve[s] a selective collaboration with appropriation of idioms of the metropolis or the conqueror† (Pratt 488). In the New Chronicle, Poma’s story is written in two languages, Spanish and Quechua which is an Incan language. Spanish is considered the dominant language, or culture, whereas the Incan language is considered to be the subordinate language and culture. Poma writes his story from the Incan point of view where he attempts to rewrite history through their eyes rather than the Spanish. Transculturation is represented because he uses the main ideas from the dominant culture, such as Adam and Eve, and then in turn incorporates the Incan culture while pushing some of their ideas back on the dominant culture. This is where you see two cultures interact, and form very different cultures from their origina l state, but more similar to each other. On the same note, Poma writes the story based on representation others’ have made of them, and by incorporating both cultures, the story can be considered an autoethnographic text. Similarly, Wideman’s text can also be considered an autoethnographic text. We see both of these terms represented in Wideman’s â€Å"Our Time,† as well as the ideas from Poma’s story. Wideman does a great job of incorporating different idioms to represent Bolduc 3 himself, as well as his brother Robby, in order to paint an accurate picture of the community and culture in which they are each a part of. For example, in the preface, the terms â€Å"ghetto† and â€Å"gangster† are used to describe their black community of Homewood— which can be referred to as indigenous idioms. Indigenous idioms are the common way of speaking within ones’ own community. A quick example of this would be how some stated refer to soda as soda, or pop, or coke, while they are all referring to the same thing. In the text, the community of Homewood is considered to be the subordinate culture. This culture stems from the dominant culture of Pittsburgh showing how the story can be considered an autoethnographic text. This is because Wideman is using the autoethnography to sort of push back against the typical Pittsburgh  culture, and show people how it actually is. John and Robby’s family moved from the dominant culture to Homewood. Wi th them they brought ideas from both communities together creating a contact zone. Due to them growing up in a white community, Robby became intrigued with the black community from a very young age. This is because he grew up surrounded by whites who would never tell him about it. As he says in the text, â€Å"I decided I’d find out what it was all about. Didn’t care if it killed me, I was going to find out† (Wideman 678). This helps us see why Robby immersed himself in the culture of Homewood, while also getting in touch with Robby’s voice in the text. Because of Robby’s fascination, he gets sucked down a path of crime, which eventually leads to jail. On the other hand, Wideman finds himself more immersed in the dominant culture. He goes through a series of very fortunate events, leading him to becoming a successful, established writer. Both brothers grow up in similar communities but found themselves going down very separate paths, showing the diversity within the contact zone. Wideman’s goal in this story is to try and figure out why Robby and himself turned out so differently. Therefore, he wants to go through specific events in order to figure this out. He Bolduc 4 writes â€Å"Our Time† in a way that most readers are not used to. Instead of writing a basic story of his brother’s life, he instead incorporates himself into it, as well as his thought processes throughout. Because he writes his story based on his brother, parts of this reading can be considered ethnography. Ethnography can be defined as a text that is based on someone other than the writer, just as Wideman writes about Robby. Wideman’s goal is persuade us to find value is his project. Readers also mix his ideas with theirs, in which they develop their own ideas based on Widman’s story, as well as give feedback. This gives a sense of transculturation, because just listening to Wideman’s points allow us to adopt some of his culture. Wideman explains to us the different ways he thought about starting the story as well as certain habits he must overcome in order to make his project successful. He ends up starting off with a story explaining the death of his brothers’ friend, Garth who died of a disease because he did not receive proper treatment, due to being black. This can be considered a contact zone  because the dominant culture represents themselves as the superiors in this situation, showing the diversity of the contact zone. Not only does this paint a picture of the world they live in, but also gives us some back round on reasons why Robby ended up living a life of crime that eventually lead him to jail. Garth’s death shook Robby and his community. They knew he had been treated unfairly and because of that they had hatred towards the dominant culture. This could be a reason why Robby chose to rebel against it, and dive into the Homewood community and culture— which showed him the life of crime. Garth’s death is one of the many instances in which we see the community that the brothers lived and grew up in. Wideman writes this section using Robby’s point of view as a way to try and understand why Robby ended up like he did, which is an example of ethnography. For instance, Wideman shows Robby’s point of view when he describes Garth. Explaining that he â€Å"looked bad. Real Bad. Inchabod Crane anyway, but now he Bolduc 5 was a skeleton† (Wideman 658). Here, Robby is providing us with a description of what Garth looks like, but Wideman is writing it, making it ethnography since it is not from Garth’s person. Along with that, Wideman shares with us another moment in time which he considered starting the story from. His other way was with the day Robby was born. Robby’s birthday was surrounded by times of death and sadness. It was almost as if it was completely overshadowed by it, almost as if there was a low gloomy storm cloud above it. Wideman shows us the effect it had on his brother by saying that â€Å"Robby cried a lot on his birthdays† (Wideman 684). This instance could have a lot to do with the way Robby ended up in jail. He was never truly celebrated on his special day; instead it contained tears and depression. Wideman uses this as an example of the factors that lead to his life of crime. He uses his own view of Robby to portray autoethnography. He writes it so that we see the way others view Robby in this situation, as well as they way Robby feels viewed, and then puts it into his words. I wondered why he switches points of view mid story. But then I realized that the whole reason he included Robby in his story was to counter ideas about Robby, whether they be his own, or other people in town. By switching to Robby’s voice, it gives a different insight. One that Is from Robby, and this helps strengthen the  autoethnographic element by opposing whatever claims and judgments that Wideman or even the reader may have, and shows us how things actually are. Throughout the story we see examples of what we can call Indigenous texts, where Wideman is trying to connect to what Robby is saying. In order to connect with Robby in the way that he wants, Wideman realizes that he has to overcome some of his habits. The biggest habit he had to overcome was â€Å"listening to [himself] listen to him† (Wideman 672). He had the tendency to hear Robby in his words rather than really listen to Robby’s point of view, which is important in order to create and autoethnographic text. Therefore, when putting material together Bolduc 6 he had to focus on breaking this habit. He had to see Robby through Robby’s eyes in order to make his project successful, which he did. Another habit Wideman had to overcome was to avoid having his story sound poetic and fictional. He wanted us to truly hear Robby’s voice and get an accurate idea of his community, and to do that; he had to drop some of the fancy words and phases so it didn’t overshadow the true point of his project. A third habit he had to overcome was the feeling of guilt about success and luck he has received throughout his life. He questions multiple times in the text why they turned out so differently. He feels guilty that his brother ended up in jail and he turned into such a successful writer. In conclusion, Wideman shows his side of the story along with his brothers, creating a piece of writing that differs from what we may consider to be usual, or conventional writing. Wideman steps out of the norm by describing his process of writing thr oughout the story. By doing this, along with providing different perspectives, he was able to create an autoethnographic text while also incorporating ethnography. Also, by giving us a glimpse of different cultures and communities that they grew up in, Wideman was able to create transculturation as well as show us the contact zones that come up within the story. All of these ideas lead back to Pratt’s ideas of contact zones, as well as Guaman Poma’s New Chronicle, providing us with instances to portray Pratt’s significance as well as Wideman’s. Wideman’s goal was to show us the ways in which he and his brother turned out so differently, and I think he succeeded. He was able to verify Pratt’s idea of contact zones  and show us his personal experience of the diversity within them. Also, he was able to help us understand the background behind Robby’s life of crime and accurately show why they ended up on different paths. This is what made Wideman’s project successful. Bolduc 7 Works Cited Wideman, John. â€Å"Our Time.† Ways of reading. 9th ed. Editor David Bartholomae & Anthony Petrosky. Boston: Bedford/St. Martin, 2011. 655-694. Print Pratt, Mary. â€Å"Arts of the Contact Zone.† Ways of reading. 9th ed. Editor David Bartholomae & Anthony Petrosky. Boston: Bedford/St. Martin, 2011. 655-694. Print

Propeller

ELECTRICAL ENGINEERING – Vol. III – Direct Current Machines – 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 E– 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 – Step Rate 8. Conclusions  ©Encyclopedia of Life Support Systems (EOLSS) ELECTRICAL ENGINEERING – Vol. III – Direct Current Machines – 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 E– 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.  ©Encyclopedia of Life Support Systems (EOLSS) ELECTRICAL ENGINEERING – Vol. III – Direct Current Machines – Edward Spooner 2. 1. Permanent Magnets Permanent magnets are generally made of iron, cobalt, nickel or other ‘hard’ 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 E– 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 magnet’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.  ©Encyclopedia of Life Support Systems (EOLSS) ELECTRICAL ENGINEERING – Vol. III – Direct Current Machines – Edward Spooner A method of remembering the direction of magnetic flux around a conductor is the right-hand â€Å"cork-screw† 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 E– 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  ©Encyclopedia of Life Support Systems (EOLSS) ELECTRICAL ENGINEERING – Vol. III – Direct Current Machines – 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 E– 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  ©Encyclopedia of Life Support Systems (EOLSS) ELECTRICAL ENGINEERING – Vol.III – Direct Current Machines – Edward Spooner U SA NE M SC PL O E– 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  ©Encyclopedia of Life Support Systems (EOLSS) ELECTRICAL ENGINEERING – Vol. III – Direct Current Machines – 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 E– 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  ©Encyclopedia of Life Support Systems (EOLSS) ELECTRICAL ENGINEERING – Vol. III – Direct Current Machines – 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 E– C EO H AP LS TE S R S – 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] â€Å"The performance and design of direct current machines. † Pitman Edwards J. D. (1991) â€Å"Electrical machines and drives : an introduction to principles and characteristics. † Basingstoke : Macmillan Fitzgerald A. E. , Kinglsey C. Jr. , (1961) â€Å"Electric Machinery† 2nd Edition, McGraw Hill. [Comprehensive text on electric machines. ] Guru B. S. , Hiziroglu H. R. , (2001) â€Å"Electric Machinery and Transformers† 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 Australia’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.  ©Encyclopedia of Life Support Systems (EOLSS)

Matthew B. Brady essays

Matthew B. Brady essays Mathew B. Brady: Civil War Photographer Mathew B. Brady: Civil War Photographer was written by Elizabeth Van Steenwyk. Elizabeth Van Steenwyk has written many good books for young people including: Saddlebag Salesmen, The California Missions, Frederic Remington, The California Gold Rush: West with the Forty-Niners, and Ida B. Wells-Barnett: Woman of Courage. Elizabeth now lives in San Marino, California with her husband. Mathew B. Brady was born somewhere between 1823 and 1824. His early life is somewhat a mystery. He was born in Warren County in New York and his parents might have been Irish immigrants. His middle name was even a mystery, when asked what the B stood for he said that he inserted it because it seemed more distinguished. When he turned 16 he met William Page, a man wanting to become an artist. The both of them worked together, and Pages artistic abilities were most likely Bradys starting interest in becoming a photographer. In 1839 or 1840 Brady and Page moved to New York City. Meanwhile, a French inventor named Louis-Jacques-Mand Daguerre was inventing something that would change Bradys life. In 1839 Daguerre invented his camera. Samuel F. B. Morse went over to France to check out Daguerres camera. He wrote back to a magazine saying that it was perhaps the greatest invention in this age. When Samuel Morse returned to New York City and started a school for learning how to use the camera. Brady, very interested in the camera, signed up for lessons. Several years later Brady graduated and started his own little photography business on Broadway. In 1844 Brady won first place in the first photographic contest in America. Winning the contest also won Brady a lot of clients. He became very popular in New York. He took pictures of twenty-five famous people and therefore published The Gallery of Illustrious Americans. He opened an ...

Cultural Anthropology Essay Example | Topics and Well Written Essays - 250 words

Cultural Anthropology - Essay Example In fact, the latter part of the Neolithic Age showed that these people also developed pottery especially those group found in the Near East. When it comes to society, the Hunter society is considered flat since there is no hierarchical authority and the social structure is egalitarian. The hunters are usually grouped in a band that has an average of 15 members. On the contrary, the Neolithic Man are usually grouped in tribes with at least â€Å"150 up to 2000 members† ( Rigby, 2000). However, like the hunter society, studies about Neolithic Man also revealed that hierarchy is not evident in their society. Many scholars believed that both societies had â€Å" primitive communism† wherein they all equally worked hard for the benefit of the community. Also, the social life of these groups mainly focused on the home and their families. The â€Å" primal religion† of these two groups are similar. These societies believed in a concept of â€Å"god† that existed in nature. God was magical for them since he existed in forms such as thunder, fire, lightning which they showed much respect. These two groups also believed that people have spirits and that they travel into another dimension. Even in the hunter society, burial was practiced which illustrated their respect for the dead body. Shamans or witchdoctors were also recognized as people who can heal or communicate with spirits. In short, religious beliefs already pervaded the life of early man.

Assessment For The Financial Accounting Essay Example | Topics and Well Written Essays - 5500 words

Assessment For The Financial Accounting - Essay Example Info: EasyJet Plc along with its subsidiaries ‘EasyJet Airline Company Limited' and ‘EasyJet Switzerland', is the second largest low-cost carrier within all of Europe. Formed only in 1995, that makes it much younger than most of its direct competitors; yet the company has been able to make a great name for itself in a very short duration of time (EasyJet Plc, 2010). Following are some achievements of the company (EasyJet Plc., 2011): Info: EasyJet Plc along with its subsidiaries ‘EasyJet Airline Company Limited' and ‘EasyJet Switzerland', is the second largest low-cost carrier within all of Europe. Formed only in 1995, that makes it much younger than most of its direct competitors, yet the company has been able to make a great name for itself in a very short duration of time. Following are some achievements of the company (EasyJet Plc., 2011):   48.8 million passengers flew by EasyJet in 2010 (out of 56 million flight seats).   The fleet of 196 aircraft   509 routes   Was amongst the very first companies to start e-commerce, they started selling online seats in 1997. As of today, easyjet.com remains "UK's most visited airline website".   Gargantuan revenues worth  £ 2,973.10 million. (Moneycentral; Thomson Reuters, 2011)The aforementioned figures are absolutely remarkable, especially considering the fact that this was a very bad year for airline carriers to the UK as the Eyjafjalla volcano in Iceland erupted and many flights were canceled during April-May (2010);... mpany Backgrounds EasyJet plc Company 1: EasyJet Plc Industry: Airline Info: EasyJet Plc along with its subsidiaries ‘EasyJet Airline Company Limited’ and ‘EasyJet Switzerland’, is the second largest low cost carrier within all of Europe. Formed only in 1995, that makes it much younger than most of its direct competitors; yet the company has been able to make a great name for itself in a very short duration of time (EasyJet Plc, 2010). Following are some achievements of the company (EasyJet Plc., 2011): 48.8 million passengers flew by EasyJet in 2010 (out of 56 million flight seats). Fleet of 196 aircrafts 509 routes Was amongst the very first companies to start e-commerce, they started selling online seats in 1997. As of today, easyjet.com remains â€Å"UKs most visited airline website† (EasyJet Plc., 2011, pp.6-8). Gargantuan revenues worth ? 2,973.10 million. (Moneycentral; Thomson Reuters, 2011) The aforementioned figures are absolutely remarkable , especially considering the fact that this was a very bad year for airline carriers within UK as the Eyjafjalla volcano of Iceland erupted and many flights were cancelled during April-May (2010); EasyJet executives place the estimate of damage and loss to be around ? 30 million. And then there was the air traffic control strike, which significantly affected the profits by increasing the overheads and costs. (EasyJet Plc., 2011, p.17) And even after such incidents, EasyJet managed to bring about an increase in its YoY net and gross profits, whilst increasing the revenues slightly. Tullow Oil Plc Company 2: Tullow Oil Plc Industry: Oil or Gas Exploration / Production Info: For a company with such a humble beginning, the progress that Tullow Oil has made from its inception in 1985 is nothing short of a miracle.