Thursday, October 31, 2019

Cable Wars, Fox News vs MSNBC Term Paper Example | Topics and Well Written Essays - 2500 words

Cable Wars, Fox News vs MSNBC - Term Paper Example There are actually facts and history of how media reportage influenced several nationwide actions and decisions, including the infamous civil war in Rwanda, which was believed to have started as an aftermath of a journalist’s submission on air (Schudson, 2002). In the United States and other advanced countries, the kind of media attention and hype given to politicians have said to go a long way in affecting their political carries greatly. A very popular example can be cited with the role the media played in the election of the first Black person to the position of the president of the United States of America, in the person of Barack Obama. Because of the increasingly noticeable influence of the media, there seem to be a continuous urge among most media houses to be the most noted and post popular when it comes to who has the highest following and thus most influential impact on society. This has created what has come to be known as the cable war. History of Cable News In the United States, Cable news refers to television stations that are dedicated purposely for news broadcast (Shen, 2009). Not until the 1980s, not much was known of media houses in the popularization of news broadcast as a full time journalistic business. But from the early 1980s, the pace set by early television stations that became predominantly focused on news broadcast such as Cable News Network (CNN), brought about the term in its most used sense. With time, there became a more centralized approach to cable news when some television stations started narrowing their focus or definition of news. This means that instead of focusing on news as a general term, there became cable news stations that would look into issues like only business or sports as their specialized area of news broadcast (Sparks, 2007). Apart from CNN, which came in 1980, other equally reputable cable news stations or networks followed such as Financial News Network, which came about in 1981, CNN2 in 1982, and CNBC , which was formed in 1989. It was later that other names suffered, that also came to be considered as powerhouses in cable news stations such as Fox News Channel, MSNBC and ESPNews. Among those who would later come to undertake centralized cable news services were Fox Business Network and Bloomberg Television, which focused predominantly on finance, ESPN, which focused on sports, and The Weather Channel, which does weather news. Today, hardly can anyone talk of cable news without mentioning Al Jazeera America. If the history of the development of cable news is anything to go by, one would say that there remains a bright and competitive future for the industry with more faces to surface with time (Ness, 2006). The Concept of Cable War According to media professor Lance Strate, the issue of cable war between Fox News and MSNBC is more of an ideological war rather than a chaotic media war (Schudson, 2002). What this means is that the two media platforms refuse to agree on the same lev el with it comes to most aspects of political and editorial contents. The height of the war or rivalry was however experienced in the build up to the 2012 General Elections between Democrat Barack Obama and Republican Mitt Romney. Between Fox News and MSNBC, Robbins (2012) sees what was a deliberate attempt to take opposing and biased stands that seemed to favor one political divide against the other. The same

Tuesday, October 29, 2019

Class Conflict Essay Example for Free

Class Conflict Essay Introduction: This essay aims to examine the extent to which class conflict affects education and life opportunities. The following paragraphs seek to illustrate how factors such as class position and parental attitudes affect education and life opportunities among different social classes and the conflict that lies between them. In order to understand the content of this essay it is first necessary to understand all of the possible variables involved. Throughout this essay I will examine the definitions of class, conflict, education and opportunity. The main body of the essay seeks to highlight the reason as to why people are members of certain classes and the effects this has on their chances for education and life opportunities, using the example of education in Britain. In conclusion, a brief synopsis of class conflict will be given and considerations of some of the reasons why this occurs. In answering the question through the use of an example from the social context in which class conflict effects education and life opportunities this essay aims to highlight how the conflict between classes effect a person’s right to an education and equal life opportunities. Class, Conflict, Education, Opportunity: In order to understand the content of this essay it is first necessary to understand all of the possible variables involved. Norman Goodman defines class as â€Å"a term widely used in sociology to differentiate the population on grounds of economic considerations such as inequalities in terms of wealth or income† (Goodman, 1992).In support of this the Concise Oxford English Dictionary defines conflict as â€Å"an incompatibility between opinions† (2004). In light of these two aforementioned definitions Karl Marx argues that â€Å"class conflict is not only inherent but inevitable within capitalism† (Goodman, 1992).Education can be defined as â€Å"the theory and practice of teaching† (2004). To once again quote from the Concise Oxford English Dictionary an opportunity is â€Å"a favourable time or set of circumstances for doing something† (2004). Why do we have social classes? Ultimately social classes are based on economic factors. Dating back to Victorian times, lower, middle and upper classes existed. The lower classes would have been made up of the landless labourers. Middle classes would have included the tradesmen i.e. people with a professional skill/qualification such as a blacksmith. Finally the upper classes would have consisted of the large farmers and business owners. The upper classes would traditionally employed people from the lower classes to run their farms or businesses. Although we have moved on since Victorian times, this social divide hasn’t changed much. There still remains today a prominent divide between the lower middle and upper class people. This can be seen now within the third level education in present days. Due to the economic crisis we are currently experiencing, less and less people are able to afford the luxury of a third level education. Sadly this is hitting the lower and working classes the hardest. Due to government cutbacks grants are being chopped leaving the less fortunate members of our society starved for further education. How does the conflict between different social classes effect education and life opportunities? As mentioned in the introduction class position and parental attitudes play a vital role in the effect that class conflict has on education and life opportunities. It has been proven that class position has a huge effect on parental attitudes in getting involved with their children’s school lives. A.Lareau outlines parental involvement as â€Å"preparing children for school (Lareau, 2000) , this includes assisting the child in learning the alphabet, speaking and reading stories to the child. This is to promote language development. Also parents should attend school event such as parent teacher meetings and comply with the requests teachers make of parents in furthering a child’s education. School success is positively linked with parental invol vement (Lareau, 2000). Through research it has been proven that a lack of â€Å"parental involvement is not random and that social classes have a powerful influence on parent involvement patterns† (Lareau, 2000).For example, â€Å"between forty and sixty per cent of working †¦ and lower-class parents fail to attend parent teacher conferences. For middle-class parents these figures are nearly halved, i.e., about twenty to thirty per cent. (Lightfoot1978, et al.). This is also proven true when we turn to the promotion of language development. These areas include â€Å"reading to children, taking children to the library, attending school events and enrolling children in summer school† (Lareau, 2000). Middle class parents were shown to take a more active role in schooling than the parents of middle and lower class children. Originally to enter the secondary educational system in Britain a fee had to be paid. It was privately organised and based on â€Å"differentiation along lines of socia l class† (McCulloch, 1998). The working and lower classes were only obliged to attend elementary education. Secondary education was intended solely for the wealthier middle class. The very wealthy and sons of landowners attended the â€Å"nine great schools of Eaton, Harrow†¦Merchant Taylors and St. Paul’s† (Sally Power, 2003), these were originally called public schools. Within the middle class there was a differentiation in the line of secondary education. This was shown by the Taunton Commission of the 1860s. Schools were divided into 3 categories depending on their clientele. The first group was catered for the sons of professional men, men in business (â€Å"whose profits put them on the same level as the great majority of professional men† (McCulloch, 1998)).This grade continued to the age of 18 or more. The second grade was much broader in its general curriculum than the first. This continued till the age of 16 and catered for the sons of â€Å"large shopkeepers, rising men of business and the larger tenant farmers† (McCulloch, 1998) .The third group catered for the â€Å"distinctly lower scale† such as small tenant farmers, small tradesman and superior artisans. This grade continued only till the age of 14. Gradually, however, access to secondary education was widened. The 1902 Act introduced a scholarship route which enabled intelligent products of elementary education to â€Å"proceed to free places in secondary education† (Roberts, 1977). Then, all children, â€Å"with exception of approximately five per cent whose parents desired and could afford an independent education† (Roberts, 1977), were given an equal opportunity with entry to different types of secondary schools that were introduced. â€Å"This depended solely on their performances in an impartial selection procedure that became known as the eleven-plus† (Roberts, 1977). At this time (1944) it was believed that society had reached equality in terms of secondary education and that each child was the maker of their own destiny depending only on their own accomplishments and hard work and not upon the socio-economic status of their parents. Now, However it is common knowledge that the 1944 Act was not successful as government reports showed that a â€Å"strong link remained between children’s educational attainments and their social class origins† (Roberts, 1977). Investigation showed that, in what was meant to be an equal opportunity of education for all, working class children seemed to â€Å"fall at every hurdle†. Social class was shown to be related to the allocation of children in primary school streams, their achievement in the eleven-plus selection procedures, â€Å"the streams towards which they gravitated within secondary schools† (Roberts, 1977), their chances of remaining in education passed the statutory age and also their resulting chances of entering higher education. Hence affecting their chance of employment in their future life which would enable them to support their family and hence being amore active member of the society in which they live. Conclusion: To conclude, from my research I do believe that class conflict has an effect on education and life opportunities as mentioned above parental attitudes and class position can have a devastating effect on a child’s life but it can also have a positive effect. This is down to where one’s family lies in the class structure. Trends show that many members of lower classes do not succeed in education as much as the members of the wealthier middle classes. This lack of success in education is often presents itself in further life. Bibliography: 2004. Concise Oxford English Dictionary. s.l. : Oxford University Press , 2004. Goodman, Norman. 1992. Introduction to Sociology. New York : Harper Perennial, 1992. Lareau, Annette. 2000. Home Advantage. Maryland : Rowman Littlefield Publishers , 2000. Lightfoot1978, Ogbu1974, McPherson1972 and Galen1987, Van. McCulloch, Gary. 1998. Failing the Ordinary Child ? Buckingham : Open University Press, 1998. Roberts, Cook, Clark, Semeonoff,. 1977. The Fragmentary Class Structure. London : Heinemann Educational Books Ltd, 1977. Sally Power, Tony Edwards, Geoff Whitty ,Valerie Wigfall. 2003. Education and the Middle Class. Buckingham : Open University Press, 2003.

Saturday, October 26, 2019

Materials Used For Making Gears

Materials Used For Making Gears Tribology has been there since the beginning of recorded history. Tribology is the word basically derived from Greek in which tribos means rubbing. From this we understand that Tribology is the scientific study of interacting surfaces and of related subjects and practices. [1] The 3 factors that are considered to be a major factor in tribology are friction, wear and lubrication. Friction is defined as the opposite force created when 2 surfaces are in contact. Friction can cause damage to the parts in contacts due to the heat generation and this can be studied using tribology. Wear is defined as the irregularities caused in a surface due to the external factors. Running a machine with weared parts can reduce the life of the machine. Lubrication is defined as the viscous liquid applied between two surfaces in contact for better performance and longer life. Fig. 1: Gears [8] Gears are means by which power is transferred from the source to the application. [2] In the present world it has been used in most of the mechanical machines so that power can be transferred in an easier and sufficient way. The gearing technology started at about 100 years before and it was carried out by the Europeans in the Dark Ages to bring out the development in the gears. [2] As years passed by more developed versions of gears were introduced which were lightweight, with high speed and gears that could withstand high loads. The gears are used as an important component in automobiles so that power is transmitted from the engine to the wheels to cause an increase in the speed of the vehicle. Hypoid gears are one of the common gears used in automobiles to do this operation. [2] Transmission which is defined as two or more gears working in tandem is used as an important principle in automobiles. Untitled.jpg In todays world many gears have been developed and these gears are being used for different purposes. These gears have been been divided into 2 such as: External Gears: In these types of gears the teeth can be found outside the cylinder or cone. Internal Gears: These types of gears have teeths in the inner surface of the cylinder or cone. With either internal or external gears a lot of gears have been developed for different purposes and these gears are explained below:Spur Gears Spur gears: This is one of the most common types of gear. These gears have teeth perpendicular to the face of the gear and the edge of the tooth is parallel to the axis of rotation. The disadvantage of these types of gears is that they are a little noisy at low speeds and this reduces to a minimum at higher speeds. [7] Fig. 2: Spur Gear [9] Rack and pinion gears: This type of gears consists of a rack more like a spur gear with infinite radius of curvature and a pinion gear which keeps on rotating over the rack. These types of gears are mainly used to convert circular motion into linear motion. Trains run on railway tracks based on this principle. Racks Gears Fig. 3: Rack and Pinion Gear [9] Helical gears: Helical gears are almost similar to the spur gears. The difference is that the teeths are in a helicoids shape and are not parallel to the axis of rotation. [7] It is less noisy than the spur gears and is widely used in industries. [7] Double helical gears are also used which has helical gears kept inversely on both sides. Helical Gears Fig. 4: Helical Gear [9] Worm gears: These are the type of gears that consists of a concave teeth profile and this teeth is usually engaged to helical gears. It is used where power is to be transferred at 90 degrees. Here sliding motion is caused rather than helical motion. [7] Heavy lubricants with good film thickness is used to prevent contact of the metals because since the teeth is small there is a chance in breakage of the teeth causing higher maintenance of the gears. Worm Gears Fig. 5: Worm Gears [9] Bevel gears: These types of gears have conical shaped teeths. It is mainly used to connect shafts to intersecting lines. The angle between 2 bevel gears can be between 0 to 180 degrees depending upon the purpose. Bevel gears with equal number of teeths and shafts at 90 degrees are called miter gears. Spiral bevel gears also known as hypoid gears are used in automobiles. These gears will always have shafts at 90 degrees. Bevel Gears Fig. 6: Bevel Gears [9] Epicyclic gears: Here 2 or more external gears move inside an internal gear as shown in Fig. 8. These types of gears are mainly used in mechanical differentials. http://t1.gstatic.com/images?q=tbn:plRNuhlKzzM8lM:http://www.monarchbearing.com/images/planetary-gears.gif Fig. 7: Epicyclic Gears [9] In all the types of gears above due to their contact with each other a frictional force is created between them and due to these frictional forces it can cause wear to the gears. Here the tribological factors come into play and reduce the life cycle of the gears. This can also cause the tooth of the gears to break. So lubricants have to be used to an extent to improve the life of the gears and materials have to be used according to the kind of environment in which the gears are to be used. Materials used for making Gears: Gears can be made from a wide variety of materials such as wood to high steel alloys depending on the requirements. Gears in different mechanical machines needs different materials to overcome the surrounding obstacles, for longer life of the equipment and the machine and also to reduce the cost. Due to these the design of gears will always depend on the accuracy level needed for the gears, load to be applied on the gears, speeds to which the gears will rotate, the noise limitations and the material to be used. So the cost of the gear will always depend on these factors. [2] So while selecting materials we should consider the tribological factors that would affect the gear while its operation like: Allowable bending and Hertz stress because as the bending stress is low there is a chance for the gear to get bend at higher temperatures. Wear resistance as the gears and gear tooths should not get weared at higher speed of rotation of the gears. Impact strength as the gears should not break when it is engaged with higher force with another gear. Water and corrosion resistance to resist against corrosion due to lubricant action. Manufacturing cost to make the gears profitable Size and weight so that the gears can be used in all machines Lubricant requirements to see that costly lubricants are not required to maintain the gears. Dimensionally stable and reliable. Stress free structure [3] Depending upon these factors, different materials are used and the details about properties of the materials and the conditions on which these materials are used are given below: Plastics: In the past, gears were made of wood or phenolic-resin impregnated cloth and as years passed by more light weight, low cost gears were required. With the invention of new polymers in plastics it gave more opportunities for the preparation of light weight, low cost gears. For this the most common plastics used today are acetate and nylon resins. This plastic gear reduces the cost of the gears when produced at large quantities and also is sometimes mixed with metals for longer and quieter operation of the gears. But since these acetate and nylon resins gears are limited to certain conditions such as strength, temperature resistance and accuracy it was required to make a different polymer for the preparation of the gears and a different polymer called Polyamide was developed. This polyamide molded gears could resist higher temperatures and could be used in certain situations in place of metal gears to overcome the tribological factors but due to its higher cost for production its still not used in all situations. [2] Non-ferrous alloys: Titanium is also another material that can be combined with other metals to form a gear. Also the die cast materials like zinc, aluminium, brass, bronze are also used for gears due to its high corrosion property, high strength, less machining. These non ferrous alloys can be used for making gears because it can overcome most of the tribological factors. But these metals cannot be produced at large quantities due to its high cost of production. [2] Cast iron: Cast iron is used for the preparation of gears because of its low cost, machinability and moderate mechanical properties. There are 3 types of cast irons differentiated basically depending on the structure of graphite in these irons. These are gray iron, malleable iron and ductile iron. Out of these the malleable and ductile irons have good shock resisting property and are mostly used in most of the gears by mixing it with other metals so that the gear made from this will be able to overcome most of the external factors affecting tribology. [2] Sintered Powder Metals: These metals are used where high production is required with low cost. The process is simple where powder is put into the suitable high pressure die. A wide variety of selections of powders are available in this section of powdered metals. This sintered powder is also widely used in automotive industries by hot forming process which was recently developed to improve the mechanical properties of gears and resist against the effects of tribology. [2] Hardened steels: This is one the most commonly used material in all industries for the manufacture of gears. These types of materials are used based on the factors like load, time period for which the material will work, lubricants to be used and the surrounding conditions that affect tribology such as temperature, pressure and humidity. When the gears are to be run at moderate temperature a low alloy material will be used for the production of gear and if the work load on the gear is to be high a high alloy material will be used after case carburizing or case nitriding to increase the fatigue strength. Of the 2 processes the case carburizing will have more distortion than the case nitriding process and would require an additional grinding process that would cause an increase in the cost of the gears. [2] Steel alloy is mostly used for the production gears more than normal steels. The materials used for gear preparation are an important factor for the preparation of gears as the working, the life of the gear, strength of the gear will all depend on the material. The material chosen must also be able to withstand the friction, wear and lubrication and have to be overcome to have long lasting and strong gears. If correct material is not chosen according to the criteria the machine can be of a complete failure and may not work properly. While selecting the materials the following factors have to be considered: Surface of the gears: The surface of gear has an important part in the life cycle of the gear as it must be able to withstand friction, wear and it must be able to properly engage with other gears and provide the required power to the required output shaft. For gears the surface texture which is defined as the combinations of imperfections on a surface [11] must be smooth and the gap between two teeths must be of proper size so the the 2 teeths are engaged correctly to each other. Eventhough gears now produced are with poor geometrical perfection or quality of surface texture companies is trying hard to produce gears with reduced surface texture by processes such as honing, lapping and super finishing methods. This is the opposite force caused when one body moves tangentially over another. The force can cause heat between the surface and can lead to the wear of the parts. The quality of the material used and the surface roughness decides the amount of friction that would occur on the surface of gears and this inturn decides the depth of wear that would occur on gears.The different types of wears that occurs on the surface of gears are given below: Adhesive wear: This type of wear occurs on the tooth surface and is very difficult to find. Here the surface of the tooth gets a quashed look due to the long running of the gears. A moderate adhesive wear can also be caused on the gear surface due to variable loading of on the gear at different times. [15] The moderate adhesive wear will appear bright and can be seen with the naked eye 9as shown in fig. 11). Untitled3.jpg Fig. 9: Moderate Adhesive Wear [15] Fig. 8: Adhesive wears [15] Abrasive wear: This type of wear occurs on gear surfaces when fine or severe dust particles are present in the lubricant used to reduce friction between the engaging gear surfaces. This type of wear is mainly seen in machines used at cement factories, road laying machines, mining machineries etc. The abrasives can cause the surface texture of the gear to change which in turn causes the application of more lubricant to the surface for the smooth running of the machine. [15] The abrasives in the lubricant can be of 2 types and cause wear to the gear in 2 methods which are classified as mild abrasion and severe abrasion. Mild Abrasion: This type of wear is caused when mild or fine particles are present in the lubricant and this causes wear on the surface of the gear. This cause only small marks on the surface of the gear and wear increases in the longer run of the gears. [15] Severe Abrasion: This type of wear is caused when large particles are present in the lubricant. It causes a larger wear in the gear and also can cause the breakdown in the machine. [15] Corrosive Abrasion: This type of abrasion is caused when the chemicals in Lubricating oil reacts with the surface. [15] Conformity: It is defined as the degree of agreement between the surfaces.[1] The degree of conformity must be maximum for gears to exactly engage and run for a longer period of time. Initial wear can increase the conformity between the gears. If the right amount of lubricant is added during the initial wear period the initial wear will stop by itself and increase the conformity between the gears. High conformity is found mostly between 2 flat surfaces. The lowest conformity is found between a flat surface and a ball.[1] Surface Texture: It is surface condition that depends on the material of manufacture, the way in which the material was processed, the lubricant used on the surface and the type of wear that occurs on the surface. Surface texture is an important factor for gears movement of the gears and the degree at which the gears touch each other depends on this property. Below the figure shows the terms that are used for defining the surface texture: Untitled 2.jpg Fig. 10: Terms used for Surface Texture [3] The irregularities in the surface of gears must be reduced to minimum while making a gear so that the thin film lubricant can run smoothly between gears and reduce the tribological factors between the gears. The surface finish should be smooth and must be free from sharp irregularities to increase the fatigue strength of the gear and this should be maintained throughout the gears to have a quieter operation. [3] The surface of the gear which is to be in contact with the other gear has to be of higher strength so the tooth dont get weared out easily. The precision of the gears structure should be considered for long lasting of the gears. The surface of the gears can be improved using methods like polishing, heat treatment methods, Lubrication for smoother operation of gears: Lubricants are a viscous fluid applied between 2 gears for reducing the heat generated between them and to lubricate the teeth to reduce the friction between the gears. The selections of lubricant have to be correct to in order to provide high efficiency, good reliability, low maintenance and long life for the gears. [4] Generally the gear operates in 3 modes of lubrication mainly boundary, mixed, full film and hydrodynamic lubrication. The boundary condition is attained when the gear is started or stopped. With increase in relative motion the mixed lubrication condition is obtained and with further increase in speed the gear is said to run at full film lubrication.[3] If there is a lubricant between the 2 contact surfaces and it is sufficient to protect the gears from contact then the lubrication is called as hydrodynamic lubrication. [1] The lubricant differs from the normal liquid by the property of viscosity. Viscosity is defined as the measure of the fluids resistance to flow. [ 13] Since gears would be under high pressure and sliding it would require a medium to high grade lubricant. As the viscosity of lubricant increases the lubricant is said to be more reliable for the gears. A gear lubricant is said to have the below factors for obtaining a good performance from the gear: thermal and oxidative stability thermal durability compatibility with seal materials protection against excessive gear and bearing wear high-temperature extreme pressure protection gear and bearing cleanliness emulsibility characteristics rust and corrosion protection, especially to yellow metal components antifoaming characteristics [5] The major tribological factors of the lubricant are: Viscosity: It is a property of the lubricant for providing the lubrication affect to the engaging gears. The viscosity of the lubricant can protect the gear from friction. Higher the viscosity greater the protection to the gears. Additives: It is a chemical substance added to oil to increase the property of oil and protect the gear against wear. Additives can protect the gear from wear and overheating. Better the additives greater will be the protection for the gear. Contamination: It is the addition of an external component in the lubricant that could reduce the property of the lubricant. This is a disadvantage for gears. If the contaminated substance is large it can cause a breakdown to the gears. Degradation: It is the wearing out of some parts of the gear due to chemical reactions. This is also a disadvantage to the gears. More the degradation more the chance for the tooth to break off. The below table explains the factors affecting selection of industrial gear lubricants: Factor Requirement Gearing Type Spur and bevel Helical and spiral bevel Hypoid Worm Low slide, low speed Moderate slide, moderate to high loading High slide, high loading Excessive sliding,moderate to high loading Loading High loaded industrial gear drives requires the use of extreme gear pressure gear lubricants. Surface finish Rougher surfaces requires high viscosity oils Smoother surfaces can use low viscosity oils Transmitted power As load is increased viscosity must be increased. Gear speed The higher the speed of the gear drive the lighter the viscosity needs to be Materials compatibility Some types of extreme pressure additives can attack yellow metals like brass and bronze Temperature The industrial gear lubricants viscosity must be selected based on the lowest and highest operating temperature. Table 1: Factors affecting selection of gear lubricant [6] Types of gear lubricants: There are lots of oil used as lubricant for gears to reduce wear,to protect against corrosion, to protect the gear against oxidation and to prevent the formation of foam between the 2 gears. [12] Inhibited oil: This is a lubricant used to prevent the corrosion and foaming between the gears. [12] Extreme Pressure Oils: These oils contain inhibited oils and chemically active substances and are used for modifying the friction acting between the 2 engaging gears.[12] Compounded oils; These are oils made from steam cylinder stocks compounded with fatless additives. The purpose of this oil is also to reduce friction.[12] Open gear compounds: This lubricant consists of additives and is used for high, slow speed heavily loaded gears. This lubricant protects the gear teeth from damage.[12] Greases: This is one of the commonly used lubricants. It consists thick soap contents. It can only be used on low speed gear surfaces.[12] Methods of lubrication: Grease Lubrication: This type of lubrication is used at gears with0 to 6 m/s tangential speed. It can be applied on all types of gears operating at low speeds. Excess of this lubricant can lead power loss and viscous drag.[5] Splash Lubrication: This type of lubrication is applied to gears with speed of 4 to 15 m/s tangential speed. Here the lubrication is done by running the gear through an oil bath. The lubricant is effective only from 3 m/s speed of the gear and the oil should be prevented from mixing with some other liquid or particles which could cause a damage to the gear teeth.[5] Spray Lubrication: This type of lubrication is applied to gears with more 12m/s of tangential operating speed. Here the oil for lubrication is sprayed through a nozzle. The nozzle should be engineered properly as there is a chance for the oil to get deflected out of path of flow by centrifugal force or by the air that is flowing out. [5] Lubricants can protect the gears from the tribological factors such as friction and wear. We know what are the types of lubricants to be used, their applications and the types of lubrication processes. It is important that we select the right amount and quality of lubricants for the gears so that they have a longer life and dont get weared out easily. Engineers are still now researching to find the best lubricant for gears so that defects in gears like scoring, scuffing, pitting doesnt occur at all for gears. The gear noise is also prevented to an extend by lubrication. Operating Conditions for Gears: Operating conditions are important tribological factors for gears as this will determine the lubricant to be used, the material to be selected for making gears. The operating conditions of gears are determined by the factors like load applied on the gear, the speed at which the gear is about to rotate,relative motion between the gears, environmental condition, the product of pressure and velocity acting on the gears and the temperature on which the gear is about to work. These operating conditions which are to be considered for operation of gear are applied below: Load: Load is the determining factor for the strength of a gear which determines the material to be used for the gear production, the amount of rubbing that would occur between the gear surfaces, the whole network of surface stresses that would occur in the contact zone of the gear surfaces and the coefficient of friction that would occur between the gears. The load also influences the behaviour of a lubricant or the abrasive particles present in the lubricant which would cause an impact on the gear tooth directly. The other area where the load influence is known is at the bonding between the gears that is directly dependent on the degradation of the surface films, increase in contact area and on temperature. In fact loading has a major impact on the change, age and wear characteristics of the materials. The schematic diagram of the influence of load on the operation of gear is given in the fig. 11.the figure explains the stresses produced due to load applied and the effects of these substances on the element.So in order to keep the gear in good condition and free from wear the following points have to be taken into account: To keep the gears in good condition progressive loading of gears is a best way. Decrease in load variation as it would reduce the rise of cavitation in the gears Decreasing fatigue loading in gears to prevent surface fatigue wear.[14] Speed: Speed of gear is an important factor as it varies from one mechanical component to another and is an important factor for the working of the machine. The parameter of the gears that are greatly influenced by the speed of gears are : Temperature: Temperature is a factor which is greatly influenced by the speed of the gear. As the speed of the gears increases the temperature between the gears also increases leading to more heat dissipation. Inorder to maintain the temperature between the gears we have to consider a good coolant and a good heat conducting surrounding medium. Friction coefficient: The effect of speed on the friction coefficient comes into play especially in a lubricated circumstance, where this factor determines the hydrodynamic load carrying capacity. At very low speed of the gears there is a chance for the stick-slip phenomenon due to the fluctuation in friction coefficient. [14] Load Normal Stresses Tangential Stresses Elastic and plastic deformation Degradation of surface films Chemical and metallurgical bonds (adhesion) Thickness of films Viscosity Lubricant Coefficient of friction Fig.11: Schematic flow chart showing the influence of load [15] Relative motion: The relative motion involves motions like sliding, rolling, spinning and bouncing. These motion can decrease the performance of the gear and also can cause wear in the gear. The use of correct material, lubricant and designing the gear correctly can increase the performance of the gear and also give longer life to the gear. [1] Environment: Environment can cause a decrease in performance of the gear. This is caused by the contamination of the lubricant and also due to the chemical reaction of the lubricant with the gear metals. [1] Product (PxV): Here the quantity of heat generated by friction is calculated from the energy at the contact which is given by the equation E = QVf (where Q = load applied to the contact, V = displacement velocity, f = friction coefficient). Here the term PxV is used as a reference to estimate the limiting conditions for materials such as polymers, solid lubricants, self lubricating sintered materials etc. This in turn can be used as a basis for the selection and comparison of materials. Thus we are able to know the maximum PxV for certain materials and us them for the production of gears. [14] Temperature: Temperature has a major effect on the contact zone of the 2 surfaces of a gear. The temperature increase in the tooth of the gear can cause geometric distortion or loss of clearance in the tooth. It can also cause an increase in the coefficient of friction and wear to the gear. Temperature can also cause deterioration in the mechanical properties of the materials and change the properties of the lubricants. An increase in the interfacial bonds is also caused which lead to a chemical reaction between the materials. [14] Conclusion: Thus the audit of gears using the tribological factors such as material, surface, lubrication and operating conditions was conducted. It is found that gears are useful in most of the mechanical applications and also have a lot of properties that are to be taken care of while the operation of the gear. In todays world, a lot of materials are available for the manufacture of gears. These materials can only be used in different conditions and have their own advantages and disadvantages. So in future a much modern material with zero wearing property and that provides longer life to the gears have to be developed. In the case of surfaces of gears smooth finished gears are already been produced these days. A surface with normal surface texture and conformity will provide smoother running of gears in future. A lots of lubricants are available in todays world. In future a more advanced lubricant can be developed that can reduce wearing of gears completely and also help to increas e the performance of gears to the fullest. All gears today are developed for performing at a particular load and temperature above which the gear can get damaged. So in future gears have to be developed that can operate at maximum temperature and load so that wear of gears due to these characteristics can be reduced to minimum.

Friday, October 25, 2019

The Old Ball Game :: essays research papers fc

The Old Ball Game An American dream can be defined through an examination of the American lifestyle, and by picking out the most common themes. The most common themes Americans associate with are the basics: graduating at the top of the class, finding a high-paying job, settling down with the perfect spouse, a house in the suburbs with a white picket fence, two children running through the yard chasing the dog and of course apple pie and baseball. Yes, baseball is considered by many to be part of the American dream. It is through baseball that many can relive their childhood. It has been the one daily and constant event that the American society depends on to be there during every summer night. The annual fall classic, the World Series, catches the attention of the entire country. Like the New York Yankees, baseball has become a part of America. After World War II, many countries were completely demolished physically and mentally. Among these countries was Japan. Countless numbers of Japanese people were dead, and land, buildings, and entire cities were destroyed. For the first time in Japan's history, their "God" had spoken to the public destroying his immortal reputation. During the postwar years, Japan looked to the major powers of the world to develop a foundation for a new country. Included in this foundation was a need for new ideas and dreams. Of course Japan did not completely erase thousands of years of tradition and culture, but Japan did take many international ideas and transformed them into her own. In the Movie Mr. Baseball, a Japanese woman describes Japan's borrowing techniques. "Japan takes the best from all over the world and makes it Hers" (Welles). Included in the world powers of the time was America; therefore, Japan borrowed several ideas from the United States. One such idea just happened to be America's National pastime, baseball. The history of Japanese baseball dates back to the middle 1800's. They "adopted baseball from the U.S. as early as 1873" (Constable 23), but the spark for baseball ignited during the post war occupational years. A foreign student from Japan explains, "The thousands of American troops stationed in Japan after the war kindled the passion for baseball that was lacking before the war" (Akutsu). The American soldiers showed the Japanese the American ways of baseball, and the popularity of Japanese baseball has skyrocketed from that time on. Baseball in Japan has reached the top level with its professional standings. Many other countries throughout the world have tried to establish the American sport of baseball but "Japan is the only country in the world to have

Wednesday, October 23, 2019

Cultural Interviews and Assessment Essay

I am interviewing a 32-year-old male (X) from the India who has been a resident of the San Jose in the US state of California since the last 10 years. He is employed as a Software engineer in one of the software MNCs in urban parts of California. Regarding, the Asian and Pacific Islander Americans (APIA) population in the US, they are one of the fastest growing population in the US. In the year 1999, the population was about 11 million and it is expected to grow to about 20 million by 2020. In 1999, 4 % of the US population was APIA, 12 % Hispanics and 11 % African-Americans. The APIA come from several parts of the world including India, China, Pakistan, Polynesia, Micronesia, Papua New Guinea, Hawaii, Japan, Philippines, Indonesia, Korea, Vietnam, etc. One of the favorite locations in the US, the APIA population would like to settle is in the state of California. The APIA make up for about 12 % of the California population in 1999. They come from various cultural backgrounds and have diverse needs. They are one of the most diverse groups in the US, and it is difficult to fulfill their health problems due to diverse healthcare needs. Let us now go through the entire interview process: – Socio-economic factors – Mr. X earns about 45, 000 US dollars every month. He is employed in a software-MNC. None of his other family members are working. He is married and has one child. Although he came to the US in 1997, he brought his family down to the US about a year back. Mr. X feels happy that he is able to earn a good income in the US and is more or less settled. He feels that many of the Indians in the US are earning far less and are belonging to the poverty groups. However, he also feels that the organization he is working in is a small organization and the income provided is less compared to other organizations. Lifestyle – MR. X is not leading a very healthy lifestyle. Earlier as his family was not with him, he used to eat his food in eat-outs and restaurants. Due to this, he is unable to lead a healthy life. However, once his family has come home, he is able to eat a traditional Indian meal and due to this, his nutritional status has improved. He is now able to consume a balanced diet. Mr. X and his family members consume a vegetarian diet. Mr. X smokes about 5 cigarettes a day and consumes about 2 servings of alcohol (especially whisky and rum) on Saturdays and Sundays. He is able to sleep only for about 6 to 7 hours a day. This is due to excessive workload. Although his duty timings are only 8 hours, he puts in an extra 5 hours work at home. During the weekend, he has to work from home at least for 5 hours on Saturdays and Sundays. He usually gets together in family meeting and religious ceremonies on Saturdays and Sundays. Family Values – Mr. X has not had much of a family life in the US. This is because his wife and child were staying back in India, as they were unable to come to the US earlier. However, in the last one-year his wife and child have come down to California and are staying with him. His son is an 8-year-old kid, who has just joined a US Elementary school. The child goes to school for about 4 hours in a day, from Monday to Friday. Prior to this one-year, the only members of his family in the US were his cousins, uncles and aunts, who reside about 20 miles from his home. Mr. X feels that in India, family values are given a great amount of importance. Down in India, people stay in a common house with the family members. This is especially seen in villages and small towns. Family meetings are conducted every day and usually food is consumed and prayers are said in a family. During the earlier days when he had just come to the US, Mr. X had stayed with one of his maternal aunt in California. However, as his condition began to improve and his job was settled, he shifted to a separate residence. However, he continues to meet his family members during weekends. Mr. X also makes important decisions after taking the advice of the elders in the family. This is also the case in India, where elders are given a lot of respect and value. In case of any personal problem, he would first call up his uncle, a man of 67 years, and explain his problem to him. Religious preferences – Mr. X belong to a high caste Hindu family in India, and actively practice his religion. During the weekends, he attends for prayers in a temple in California. He usually makes a trip along with family members. He does follow intricate religious practices at home and at his workplace. He consumes a vegetarian diet and would take care especially whilst eating out. During the morning and before starting work, Mr. X chants a few short prayers. This he also does after he finishes work and before going to bed. His wife and child are also religious like him. He accompanies his family members during the weekends for a trip to their local temple. The local temple is about 25 miles away from their home. They also consume a vegetarian diet. In California, the number of vegetarian restaurants and eat-outs are less, due to which he has experienced problems. Health and practices – Mr. X enjoys a good state of health compared to the other APIA’s in the US. It is also important to note that the APIA’s enjoy a much better health status compared to the Whites, African-Americans and the Hispanics. In the year 1999, Mr. X suffered a bout of malaria. He suffered from the illness for about 15 days, and required admission in the Hospital. During his earlier days in the US, Mr. X did not have health insurance. Hence, he had to pay for his hospital bills. In the year 2000, the organization he was working with provided him with health insurance, which helps him to meet with his health expenditure. As Mr. X smokes excessively and due to his work-related habits, he suffers from asthmatic attacks frequently. He uses a small pump that provides Broncho-dilators. He has to consume two puffs twice a day as suggested by the physician. He also follows the advice on food and exercises suggested by the physician. Sometimes during winter months, Mr. X requires hospitalization for difficulty in breathing. This has occurred frequently in the last 4 years. His hospital bill is now covered by health insurance. The physician has repeatedly suggested to give up smoking and to follow better work-related practices, which Mr. X has ignored. The access to health is good, as Mr. X resides in an urban area. He has a hospital providing ultra-modern facilities located about 1 mile from his residence. The hospital also has physicians, specialists and nurses who are from an Indian background. This makes him a special patient at the hospital. He does feel that his physician is able to communicate with him appropriately and understand his health problem. As Mr. X has his family come in newly into the US, they do not have health insurance. However, he plans to subscribe to health insurance for them within the next six months. So far his wife and child did not require hospitalization. However, MR. X frequently takes his son for health checkups and immunizations to the pediatrician. His wife visits a female gynecologist frequently, to ensure that problems with her periods are addressed properly. She does prefer going to an Indian female gynecologist, but is unable to do so as there is a shortage of medical staff from other cultures in the US. Due to problems with financing (uninsured), she is unable to afford seeing an Indian gynecologist from another hospital. MR. X’s physician and pediatrician both belong to the Indian community. Child-bearing/parenting practices – Mr. X has just one son, and he plan to have one more child in the near future. However, he says that during the pregnancy period, he plans to send his wife and son back home to India, as he may be unable to take appropriate care of his wife. As family values are give great importance in India, Mr. X wishes that his son stays with him even after crossing the age of 16 or 18. He wants his soon to mix about with other children in the US, but at the same time follow Indian traditions regarding religion, diet and customs. Other issues – Mr. X and is family members do understand English and do not have any problem communicating with the people in the US. Mr. X may not consider preventive medical care. However, he does visit the local physician frequently to take medical advice and go in for routine checkups. Mr. X feels that more physicians, nurses and specialists from the Indian communities should be available to fulfill the need of the Indians in California. Mr. X also feels that the local government and the Federal government have not addressed several of the problems faced by the APIA communities in the US. This is with regards to health insurance, health access, education, working conditions, immigration status, etc. References: Ro, M. â€Å"Overview of Asian and Pacific Islanders in the United States and California. † Center for Alternative Policies. 1999. 9 Nov 2007. http://www. communityvoices. org/Uploads/om3gfk55hhzyvrn00n4nerbf_20020828090003. pdf Srinivasa, S. â€Å"Toward Improved Health: Disaggregating Asian American and Native Hawaiian Pacific Islander Data. † American Journal of Public Health 90. 11 (2000): 1731-1734. http://www. ajph. org/cgi/reprint/90/11/1731. pdf

Tuesday, October 22, 2019

gandhifighter without a sword essays

gandhifighter without a sword essays Gandhi, one of the worlds greatest figures, has already become a legend. In this book Jeanette Eaton shows him as a human being. While still a young man, Gandhi adopted the austere way of living that was until the day he died. He did not want comforts and luxuries when so many of his countrymen lived in terrible poverty. He ate only the most frugal diet and in his later years wore a peasants costume. But he himself was anything but austere. Laughter was to him lifes most healing gift, even when it was directed against himself. When young Indian children become a certain age and their body is mature enough they are allowed to get married. Gandhi was described very short and skinny with his dark eyes. He had noticed everything in his path and along the way. It was very hard for the people in the village to do anything near early dawn because only oil lamps gave off light. Gandhi had a younger brother. Before Gandhi had gone to high school he had been used to putting the jasmine wreaths on the images of Shiva and Krishna and Radha. Now every day that he has gone to school he snatchs his breakfast and leaves. Everyday before he enters the temple him and his brother slip their slippers of before they enter the temple. In this way the day began in a small town in western India. Although it was many years ago, the majority of Indian people live in much the same way now. The climate is so warm that as much work as possible is done in the early hours. Therefore many schools open soon after daybreak and, like shops and offices, close in the heat of the day. Gandhi, like any other Indian boys took being married, and going to school for granted because education was very hard for people to learn and to get a good job to not work on the fields day and night. Gandhi was very happy for that he was married to Kasturbai (his wife) because she had changed his life in both work wis ...