Technology Essay Introduction Essay Example for Free

Technology Essay Introduction Essay A rapid development of scientific and technological progress, especially in recent decades, has changed thinking of a modern person. An advent of computers has made a real revolution. They altered our approach to work, study, entertainment and other aspects of life. In hospitals, our organism is scanned by complex tomography. Up-to-grade Internet access devices are located in schools while in institutions there are various tools for carrying out calculations and experiments. Being ordinary things, laptop, mobile communications, a global network, automated production lines – thats far from a complete list of useful information technologies. Probably, people did not possess such a sum of knowledge in different fields. Amazing phenomena surround us. Today, figuratively speaking, you can get news from your pocket, connect to a network, or send a message to an individual who is thousands of kilometers away from you. Thanks to technologies, we may get acquainted with people who live in other countries and cities. Science came up with a lot of interesting and useful stuff from biomaterials to artificial hands. From a factitious kidney to contact lenses that train eye muscles at night. From digital libraries, online universities, and courses to advanced deep earth drilling rigs. Present innovations are designed to serve humanity in its quest for high peaks. However, not all technologies benefit the human being. Frequently, we could observe some reverse. For instance, modern weapons are capable of destroying both nature and human lives in frightening proportions. An industry smokes and discharges toxic waste into the water, invades the earths interior in search of resources. In the Pacific Ocean, a new â€Å"continent† of floating debris has already settled down. On the one hand, electronic pages are good, less harm is done to the environment, and storing a large amount of data is easier and more convenient in such form. On the other hand, humanity is becoming increasingly dependent on technology. Most humans cannot even imagine what they will do if, for example, they forget a phone at home. Facebook, Twitter, and other analogs have a significant influence on the well-being and sense of human satisfaction. A lot of studies noted the more time a person spends in so-called â€Å"social relations†, the higher a risk of loneliness and depression. The question arises: does this mean that global networks mostly address single and unhappy people or they make them so? Live interaction is replaced by a set of letters on the computer as facial expressions are emoticons. People just stopped going to visit and see each other. Thus, technological progress has divided the world into two camps. Some people believe that creation of complex gadgets moves an evolution of our civilization forward. Others are convinced of the extremely negative impact of such devices on human health and psyche. First of all, it is worth noting that a lot of techniques are specially established for performing the most laborious and routine job. Similar developments allow you to economize both time and space. At the same time, opponents of technical innovations are sure that they make a person lazy, deprive him/her of the opportunity to act mentally and physically. Many of our contemporaries spend a significant part of their lives waiting for the moment when robots will do all the activity without their participation. Do not forget about a danger associated with an emission of gadgets and an emergence of psychological dependence. But any phenomenon conceals in itself both positive and negative sides. In the context of technology, it is necessary to observe moderation in their applying and to remember their subsidiary rather than a dominant role in our lives.

Underrepresentation of Women in Canadian Politics

Underrepresentation of Women in Canadian Politics In November 2015, new PM Justin Trudeau made headlines around the world when he chose a cabinet made up of 50% women. Yet this in fact constituted only 30% of the women Liberal MPs elected in 2015. In the 2015 federal election Canadians elected 88 female MPs, or 26% of all MPs in the House. But this represented only a 1% increase from 2011, when 25% of all MPs elected were women. As we can see from this analysis, although PM Trudeau seemed to have figured out a way to bridge the gender gap, it however is only a percentage better than that of women representation in parliament back in 2011. Till today the representation of women in politics is still quite low. Canada is currently ranked 62nd amongst the 193 countries included in the Inter-Parliamentary Unions classification (IPU, 2017). Around the globe there has been progress when it comes to the aspect of bridging the gender gap in politics but Canada has remained stagnant for a very long time even though there have been some period s of progress. The Trudeau government now currently holds the record for greatest percentage of women representation in Canada but this still isnt enough to make significant progress. In this paper, I will be looking at the underrepresentation of women in Canadian politics, as well as reasons for this gender inequality in Canadian politics and barriers to the election of females into politics. In addition to this I will also touch on reforms that could be made to the political system to encourage more women to enter politics. A useful guide to understanding how political candidates are chosen is the demand and supply framework outlined by Pippa Norris and Joni Lovenduski. The demand side being the demand for political candidates by political parties, and the supply side on the other hand is the supply of political candidates that is the result of individual decisions to stand for election. That is the supply of individuals willing and able to step forward to stand for office (Brenda ONeill, 2015). The demand side, which is the selected candidates, suggests that the selected candidate must be the candidate with the least risk, that is, the candidate most likely to win the seat. The electoral system practiced in Canada (the first-past-the-post system) is the cause of this mentality. The electoral system being a winner take all system ensures that political parties have to put forth their best candidates in order to challenge for the seat. Existing networks and past experiences have set a standard for the pe rception of the right candidate and this has influenced choices towards candidates who meet the perception of who is most likely to win. The masculinized environment of Canadian politics that privileges power and competition hinders women from getting into politics because politicians are seen to be assertive, active, and self-confident, all these being male stereotypes. Women would have to go against their stereotypes in order to be selected for seat. Women who go into politics tend to be seen as less feminine than other women but not as masculine as men. They are defined by what they lack, femininity and specific masculine traits (Melanee Thomas, 2013).   There is no safe place for women who go into politics, they will be criticized one way or the other. Another reason for the under representation of women in Canadian politics is the concept of sacrificial lambs, women who are nominated to run in ridings where the party is not competitive (Melanee Thomas/Marc Andre Bodet, 2 013). The continuing competitiveness of Canadian politics helps notice the effect of the sacrificial lamb hypothesis. Parties are more likely to nominate men than women to run in districts that they believe can be won (Brenda ONeill, 2015). Another point to consider as to why women are under represented is the fact that party systems vary. Parties on the right side of the ideological spectrum have refused to make special opportunities to help enhance women representation. Some examples of these right winged parties with poor women representation; the Wildrose Party in the 2012 Alberta election had 13% female representation; in the 2014 Ontario election, the PC Party had 25% female representation (Brenda ONeill, 2015). The left side of the spectrum in contrast to the right has created sufficient opportunities to enhance female representation. The New Democratic Party in the 2012 Alberta election had 47% female representation and 48% back in 2009 (Brenda ONeill, 2015). The supply side ; an important factor affecting the supply of women is gender norms. In society, today, the expectations from women is quite different to that of men. They both have varying public and private roles. Men are seen to be the bread winners, that is, the person who brings income into the family, so they are brought up in a brute and disciplined manner, they are pressured to go to school in order to get a job in future which would help sustain their families. Females on the other hand are raised in a more pampered manner because they are seen to be more delicate than men and they have specific duties like taking care of their children which require extreme care and attention. Gender norms shape everything in society, from the education and occupations women and men choose to the level of political interest and knowledge that they exhibit (Brenda ONeill, 2015). Along with the existing societal norms comes the willingness of women to participate in politics. Women feel that since the socie ty doesnt deem them fit they shouldnt try to contest for candidacy if not theyll just attract unnecessary back lash from both society and the media. Another factor affecting the supply of women is time. As mentioned earlier, according to norms, women are meant to take care of their children and this eats up a huge amount of their leisure time, especially those women working full time. Research on leisure time availability shows some slight difference between women and men. Womens leisure time is eaten up by child care and unpaid domestic chores while men have theirs eaten up by extra working hours (Melanee Thomas, 2013). In addition to this, research shows that women are less interested in politics than men, so this low level of interest might hamper their willingness to run. And politics being a blood game causes for women to shy away from it. This low level of interest by women in political participation is quite problematic. It is problematic for three reasons. First, women are a historically underrepresented group (Melanee Thomas, 2013). In the past, they were blocked from access to political activities because it was seen as something women werent built for and therefore could not handle. Although these barriers affecting women representation have been removed over time, informal barriers such as media still hamper women representation. These informal barriers stop the Canadian political system from being just and fair. The second reason is that women are a heterogeneous group with a diversity of political opinions and preferences (Melanee Thomas, 2013). They view situations in a different light than men. However, due to the small number of representatives and activists, it is quite impossible for all these diverse political opinions to be represented. The final reason being the result of research. Research shows that in the legislature, womens and mens decision-making behaviour changes with the gender composition of that group (Melanee Thomas, 2013). So, men paired alongside women are more likely to have outcomes that represent both male and female perspectives towards the situation at hand unlike a team made up exclusively of men. Women are more likely to prioritize the wellbeing of the people first and this might affect the society as a whole while men who are more straightforward in making decisions, not looking at how the people would be affected but at how the society will benefit in the long run. This current low participation rate of women in Canadian politics makes us aware of the fact that there are still some barriers hindering women from participating. These barriers exist at the individual, social, and political levels (Melanee Thomas, 2013). Individual barriers include, education and income. Over time, women rights have been advocated for to bridge the existing inequality gap. The earliest studies of political behaviour argued that as womens level of education, income, and occupational status caught up to mens, so to should their levels of political participation and engagement (Melanee Thomas, 2013). This phenomenon is known as the pipeline theory of political representation. This theory assumes that once women take on the same occupations, have similar levels of education, and earn similar incomes to men, their numbers as legislators would naturally increase (Brenda ONeill, 2015). This has not been the case though. Women remain underrepresented and the education of w omen has sky rocketed compared to back in the days but women are pushed towards more feminine areas of study such as family studies, catering, social services, etc. Only a few go into areas of study which would then lead them into politics and this causes for the underrepresentation in the upper echelon of many professions despite the overall education gains. Women still earn lower than men in todays society. Women in comparison to men earn 80 cents to each dollar a man earns.   The lack of campaign finance regulations makes income a barrier. Some provinces and municipalities lack regulation and this requires for candidates to rely on conventional sources of campaign finance, including personal income (Melanee Thomas, 2013). This reliance on personal income therefore affects women because they dont earn as much as men. Social barriers are raised from societal views. As mentioned earlier, womens progress in politics is hampered by the views of society. This view that well paying jobs and jobs that require critical thinking are more masculine. These societal views have pushed women away from these jobs because they do not see themselves as capable of handling those types of jobs. And these jobs are the jobs which most Members of Parliaments held before going into politics. The top occupation for Canadian Parliamentarians in 2011 was businessman. This job does not appear in top 10 for women parliamentarians. Instead, the women who enter politics are most likely to be teachers and consultants (Melanee Thomas, 2013). The media is a major social barrier. They perceive women politicians in a discriminatory light. They feel like they are not fit for the positions which they hold and so they (the press) tend to pick on these women politicians. Womens personal relationships and physical appearance receive fa r more scrutiny from the press and other politicians than do male colleagues, and the tone of the press coverage women politicians receive is disproportionately negative (Melanee Thomas, 2013). After exceeding individual and social barriers, women still have to face political barriers. These political barriers being nomination procedures. Political parties have varying nomination processes. The Conservative Party has very few formal nomination rules. The NDP on the other hand, has a very formal nomination process. Formal nomination processes help with the representation of women in politics, that is because these processes require to seek out qualified candidates from historically underrepresented groups. However, the right-wing parties are the ones in competition for the seat and they are also the majority so they choose to pick out the best possible candidate due to the winner take all nature of the electoral system. And the best possible candidate based on the standards set by history would be a male. The candidate would most likely be male as politics is a masculinized environment and males should be accustomed to such an environment as they were brought up for living i n such an environment (Melanee Thomas, 2013). So, there is a gender bias when it comes to nomination processes. Parties on the left wing of the ideological spectrum (NDP) assist in women representation but in some cases, the strength of women representation held by these parties still leave women underrepresented. provinces with electorally strong parties on the left of the ideological spectrum will often reveal greater gender equality. BC, Quebec, and Manitoba, for example, have enjoyed strong showings amongst parties on the left and rank among the top provinces for women representation in politics. However, Saskatchewan, despite the strength of the NDP in the province, does less well (Brenda ONeill, 2015). A lot of research has gone into figuring out how to deal with this continuing underrepresentation and some solutions have been brought up to help fill in the existing gender gap.   A major solution that has been proposed is, the reform of the political system. This would help encourage more women to enter politics. A change to the current electoral system would be in favour of women representation. The current electoral system practiced in Canada is the first-past-the-post system and this being a winner takes all system is sort of masculinized therefore making sure that political parties view male candidates as the most suitable candidates in such an environment. This discourages women representation. Many of those advocating for reform seem to prefer the proportional representation system. Most countries where women occupy at least 30% of the parliamentary seats use the PR system (Julie Cool, 2011). However, the PR system might not benefit women representation. The PR system where the most widely used form is the list system may contain a lot of bias when these lists are being made. People use their own discretion to choose the names that appear on the list and nothing says that those selecting the names on the list would look to balancing gender inequality when there are more pressing issues, like the well being of the society, to focus on. PR systems need to be supplemented with more incentives in order to ensure impartiality on party lists. While some people believe electoral reform is an efficient means of bridging the inequality gap in parliament, others believe that slight electoral change would be better off. That is, Canada would function the same but with new additional rules that enable them better women representation. Some of these additional rules might include the introduction of quotas. Majority of the countries that reached the 30% mark for women representation in parliament used quotas (22 of 30 countries as at 2009). The core idea behind quota systems is to recruit women into political positions and to ensure that women are not only a few tokens in political life (Drude Dahlerup, 2009). These quotas can either be legislative or voluntary. Legal quotas are mandated in a countrys constitution or by law, usually in the electoral law. All political parties must abide by legal quotas, and may be subject to sanctions in case of non-compliance. Costa Rica, Belgium and Argentina have legislated quotas, which spec ify that a certain percentage of candidates for election must be women. There are firm legal sanctions in place if the provisions are not met (Julie Cool, 2011). Voluntary quotas on the other hand are developed at the discretion of political parties. Other additional rules proposed to help women representation were the introduction of spending limits on nomination campaigns, and tax credits for contributions to support prospective candidates seeking nomination. These rules were to aid women in the aspect of income.   (Julie Cool, 2011). Lastly, the introduction of campaign schools for women and a change in political environment. Women should be encouraged to enrol into campaign schools. These campaign schools help women to be better prepared for the tough nature of the political realm. It teaches these women how to portray themselves and fight against the barriers which stand in their way. These campaign schools are developed mainly by women or equality organizations, based on consultation from academics, civil servants, and elected officials. Some organizations that host these campaign schools in Canada are, the Nova Scotia Advisory Council, Equal Voice Canadian Women Voters Congress, and the College of Continuing Education at Dalhousie University. Although a systematic study on full effects of these campaign schools has not been undertaken in Canada, we can see that they have made significant impact in bridging the inequality gap in places like America (Melanee Thomas, 2013). Alongside these campaign schools there should also be a change in political environment in Canada. It has to be more of a women-friendly environment. The political system being highly masculinized blocks women from freely participating in politics and this causes for the masses in Canada to question the democratic status of the country. Special attention to the values, norms, rules, procedures, and practices in parliament should ensure that, once they are elected, women can apply their unique and diverse perspectives (Julie Cool, 2011). Among other options, parliaments could consider reorganizing their work to become more gender-sensitive, for example, by instituting family-friendly hours, ending parliamentary business at a reasonable time; reorganizing work schedules to allow for family days; or spreading parliamentary business over a number of shorter days (Julie Cool, 2011). Canada has remained stagnant in women representation for a very long time and it is about time to move on from this stagnation. Canadas electoral system doesnt work in favor of women because it is very masculinized and at the same time a very difficult job. This however defies the status of democracy that Canada holds. In a democracy, everyone is equal but this is not so as women are discriminated against and stereotyped as not being suitable for politics, and those who manage to get into politics are criticized as not being feminine enough and at the same time not cutting the mark for masculinity. Media bashes women politicians for the littlest of reasons, and this is because there is this established view that women are more suited for the home and not jobs that require aggression and critical thinking. All these existing barriers have then led to women looking down on themselves feeling that they are not capable of handling the nature of such a difficult job. However, we need to r ealize that we cannot just bring women into politics just because we want to bridge the gender gap. They have to work for it, just as hard as their male counterparts did. So instead of trying to advocate for a womens agenda in parliament, we should work towards the development of workable, sustainable, dynamic strategies to increase women representation in politics. BIBLIOGRAPHY Facts and figures: Leadership and political participation. UN WOMEN, UN Women, Aug. 2016, www.unwomen.org/en/what-we-do/leadership-and-political-participation/facts-and-figures. Accessed 28 Feb. 2017. Woolf, Nicky. Canadas new parliament is most diverse ever. theguardian, 22 Oct. 2015, https://www.theguardian.com/world/2015/oct/22/canada-new-parliament-most-diverse-ever. Accessed 28 Feb. 2017. Women in national parliaments. Inter-Parliamentary Union, IPU, 1 Jan. 2017, www.ipu.org/wmn-e/classif.htm. Accessed 28 Feb. 2017. Cool, Julie. Women in parliament. Parliament of Canada, Library of Parliament, 10 May 2011, www.lop.parl.gc.ca/content/lop/ResearchPublications/2011-56-e.htm#a9. Accessed 28 Feb. 2017. Brenda ONeill, Unpacking Genders Role in Political Representation in Canada, Canadian Parliamentary Review (Summer 2015), vol. 38:2, pp. 22-29 Melanee Thomas, Barriers to Womens Political Participation in Canada, UNB Law Journal (2013), vol. 64, pp. 218-233 Melanee Thomas and Marc Andrà © Bodet, Sacrificial lambs, women candidates, and district competitiveness in Canada, Electoral Studies (2013), vol. 32, pp. 153-166 Myrna Driedger, Is there such a thing as a Womens Agenda in Parliament?, Canadian Parliamentary Review (Spring 2013), vol. 36:1, pp. 11-12

Fibre optics

Fibre optics ACKNOWLEDGEMENT: History of all great works in to witness that no great work was ever done without either active or passive support of a person surrounding and ones close quarters. Thus is it not hard to conclude how active assistance from senior could positively impact the execution of a project .I am highly thankful to our learned faculty for her active guidance throughout the completion of project. Last but not least, I would also want to extend my appreciation to those who could not be mentioned here but have well played their role to inspire me behind the certain. History:- Daniel Colladon first described this light fountain or light pipe in an 1842 article entitled On the reflections of a ray of light inside a parabolic liquid stream. This particular illustration comes from a later article by Colladon, in 1884. The principle that makes fiber optics possible, was first demonstrated by Daniel Colladon and Jacques Babinet in Paris in the early 1840s. John Tyndall wrote about the property of total internal reflection in an introductory book about the nature of light in 1870: When the light passes from air into water, the refracted ray is bent towards the perpendicular When the ray passes from water to air it is bent from the perpendicular If the angle which the ray in water encloses with the perpendicular to the surface be greater than 48 degrees, the ray will not quit the water at all: it will be totally reflected at the surface. The angle which marks the limit where total reflection begins is called the limiting angle of the medium. For water this angle is 48Â °27, for flint glass it is 38Â °41, while for diamond it is 23Â °42. The groundbreaking event happened in around 1965, Charles K. Kao and George A. Hockham of the British company Standard Telephones and Cables (STC) were the first to promote the idea that the attenuation in optical fibers could be reduced below 20 decibels per kilometer (dB/km), allowing fibers to be a practical medium for communication. They proposed that the attenuation in fibers available at the time was caused by impurities, which could be removed, rather than fundamental physical effects such as scattering. They correctly and systematically theorized the light-loss properties for optical fiber, and pointed out the right material to manufacture such fibers silica glass with high purity. This discovery led to Kao being awarded the Nobel Prize in Physics in 2009. NASA used fiber optics in the television cameras that were sent to the moon. At the time its use in the cameras was classified confidential and only those with the right security clearance or those accompanied by someone with the right security clearence were permitted to handle the cameras. In 1991, the emerging field of photonic crystals led to the development of photonic-crystal fiber which guides light by means of diffraction from a periodic structure, rather than total internal reflection. The first photonic crystal fibers became commercially available in 2000. Photonic crystal fibers can be designed to carry higher power than conventional fiber, and their wavelength dependent properties can be manipulated to improve their performance in certain applications. PROCESS OF MANUFACTURING OF FIBRE OPTICS:- Illustration of the modified chemical vapor deposition (inside) process Standard optical fibers are made by first constructing a large-diameter preform, with a carefully controlled refractive index profile, and then pulling the preform to form the long, thin optical fiber. The preform is commonly made by three chemical vapor deposition methods: inside vapor deposition, outside vapor deposition, and vapor axial deposition. With inside vapor deposition, the preform starts as a hollow glass tube approximately 40centimeters (16in) long, which is placed horizontally and rotated slowly on a lathe. Gases such as silicon tetrachloride (SiCl4) or germanium tetrachloride (GeCl4) are injected with oxygen in the end of the tube. The gases are then heated by means of an external hydrogen burner, bringing the temperature of the gas up to 1900K (1600Â °C, 3000Â °F), where the tetrachlorides react with oxygen to produce silica or germania (germanium dioxide) particles. When the reaction conditions are chosen to allow this reaction to occur in the gas phase throughout the tube volume, in contrast to earlier techniques where the reaction occurred only on the glass surface, this technique is called modified chemical vapor deposition. The oxide particles then agglomerate to form large particle chains, which subsequently deposit on the walls of the tube as soot. The deposition is due to the large difference in temperature between the gas core and the wall causing the gas to push the particles outwards (this is known as thermophoresis). The torch is then traversed up and down the length of the tube to deposit the material evenly. After the torch has reached the end of the tube, it is then brought back to the beginning of the tube and the deposited particles are then melted to form a solid layer. This process is repeated until a sufficient amount of material has been deposited. For each layer the composition can be modified by varying the gas composition, resulting in precise control of the finished fibers optical properties. In outside vapor deposition or vapor axial deposition, the glass is formed by flame hydrolysis, a reaction in which silicon tetrachloride and germanium tetrachloride are oxidized by reaction with water (H2O) in an oxyhydrogen flame. In outside vapor deposition the glass is deposited onto a solid rod, which is removed before further processing. In vapor axial deposition, a short seed rod is used, and a porous preform, whose length is not limited by the size of the source rod, is built up on its end. The porous preform is consolidated into a transparent, solid preform by heating to about 1800K (1500Â °C, 2800Â °F). The preform, however constructed, is then placed in a device known as a drawing tower, where the preform tip is heated and the optic fiber is pulled out as a string. By measuring the resultant fiber width, the tension on the fiber can be controlled to maintain the fiber thickness. Principle of operation:- An optical fiber is a cylindrical dielectric waveguide (nonconducting waveguide) that transmits light along its axis, by the process of total internal reflection. The fiber consists of a core surrounded by a cladding layer, both of which are made of dielectric materials. To confine the optical signal in the core, the refractive index of the core must be greater than that of the cladding. The boundary between the core and cladding may either be abrupt, in step-index fiber, or gradual, in graded-index fiber. Index of refraction: The index of refraction is a way of measuring the speed of light in a material. Light travels fastest in a vacuum, such as outer space. The actual speed of light in a vacuum is about 300,000 kilometres (186 thousand miles) per second. Index of refraction is calculated by dividing the speed of light in a vacuum by the speed of light in some other medium. The index of refraction of a vacuum is therefore 1, by definition. The typical value for the cladding of an optical fiber is 1.46. The core value is typically 1.48. The larger the index of refraction, the slower light travels in that medium. From this information, a good rule of thumb is that signal using optical fiber for communication will travel at around 200 million meters per second. Or to put it another way, to travel 1000 kilometers in fiber, the signal will take 5 milliseconds to propagate. Thus a phone call carried by fiber between Sydney and New York, a 12000 kilometer distance, means that there is an absolute minimum delay of 60 milliseconds (or around 1/16th of a second) between when one caller speaks to when the other hears. (Of course the fiber in this case will probably travel a longer route, and there will be additional delays due to communication equipment switching and the process of encoding and decoding the voice onto the fiber). Total internal reflection: When light traveling in a dense medium hits a boundary at a steep angle (larger than the critical angle for the boundary), the light will be completely reflected. This effect is used in optical fibers to confine light in the core. Light travels along the fiber bouncing back and forth off of the boundary. Because the light must strike the boundary with an angle greater than the critical angle, only light that enters the fiber within a certain range of angles can travel down the fiber without leaking out. This range of angles is called the acceptance cone of the fiber. The size of this acceptance cone is a function of the refractive index difference between the fibers core and cladding. In simpler terms, there is a maximum angle from the fiber axis at which light may enter the fiber so that it will propagate, or travel, in the core of the fiber. The sine of this maximum angle is the numerical aperture (NA) of the fiber. Fiber with a larger NA requires less precision to splice and work with than fiber with a smaller NA. Single-mode fiber has a small NA. TYPES OF FIBRE OPTICS:- Multi-mode fiber:- Fibers which support many propagation paths or transverse modes are called multi-mode fibers (MMF). Multi-mode fibers generally have a larger core diameter, and are used for short-distance communication links and for applications where high power must be transmitted. Fiber with large core diameter may be analyzed by geometrical optics. Such fiber is called multi-mode fiber. from the electromagnetic analysis . In a step-index multi-mode fiber, rays of light are guided along the fiber core by total internal reflection. Rays that meet the core-cladding boundary at a high angle , greater than the critical angle for this boundary, are completely reflected. The critical angle (minimum angle for total internal reflection) is determined by the difference in index of refraction between the core and cladding materials. Rays that meet the boundary at a low angle are refracted from the core into the cladding, and do not convey light and hence information along the fiber. The critical angle determines the acceptance angle of the fiber, often reported as a numerical aperture. A high numerical aperture allows light to propagate down the fiber in rays both close to the axis and at various angles, allowing efficient coupling of light into the fiber. However, this high numerical aperture increases the amount of dispersion as rays at different angles have different path lengths and therefore take different times to traverse the fiber. Single-mode fiber:- Those which can only support a single mode are called single-mode fibers (SMF). Single-mode fibers are used for most communication links longer than 550meters (1,800ft). The structure of a typical single-mode fiber. Core: 8Â µm diameter Cladding: 125Â µm dia. Buffer: 250Â µm dia. Jacket: 400Â µm dia. Fiber with a core diameter less than about ten times the wavelength of the propagating light cannot be modeled using geometric optics. Instead, it must be analyzed as an electromagnetic structure, by solution of Maxwells equations as reduced to the electromagnetic wave equation. The electromagnetic analysis may also be required to understand behaviors such as speckle that occur when coherent light propagates in multi-mode fiber. As an optical waveguide, the fiber supports one or more confined transverse modes by which light can propagate along the fiber. Fiber supporting only one mode is called single-mode or mono-mode fiber. The most common type of single-mode fiber has a core diameter of 8-10 micrometers and is designed for use in the near infrared. The mode structure depends on the wavelength of the light used, so that this fiber actually supports a small number of additional modes at visible wavelengths. Multi-mode fiber, by comparison, is manufactured with core diameters as small as 50 micrometers and as large as hundreds of micrometers. The normalized frequency V for this fiber should be less than the first zero of the Bessel function J0 (approximately 2.405). Special-purpose fiber: Some special-purpose optical fiber is constructed with a non-cylindrical core and/or cladding layer, usually with an elliptical or rectangular cross-section. These include polarization-maintaining fiber and fiber designed to suppress whispering gallery mode propagation. Photonic-crystal fiber is made with a regular pattern of index variation (often in the form of cylindrical holes that run along the length of the fiber). Such fiber uses diffraction effects instead of or in addition to total internal reflection, to confine light to the fibers core. The properties of the fiber can be tailored to a wide variety of applications. APPLICATIONS OF FIBRE OPTICS:- Optical fiber communication: Optical fiber can be used as a medium for telecommunication and networking because it is flexible and can be bundled as cables. It is especially advantageous for long-distance communications, because light propagates through the fiber with little attenuation compared to electrical cables. This allows long distances to be spanned with few repeaters. Additionally, the per-channel light signals propagating in the fiber have been modulated at rates as high as 111 gigabits per second by NTT, although 10 or 40Gb/s is typical in deployed systems. Each fiber can carry many independent channels, each using a different wavelength of light (wavelength-division multiplexing (WDM)). The net data rate (data rate without overhead bytes) per fiber is the per-channel data rate reduced by the FEC overhead, multiplied by the number of channels. For short distance applications, such as creating a network within an office building, fiber-optic cabling can be used to save space in cable ducts. This is because a single fiber can often carry much more data than many electrical cables, such as 4 pair Cat-5 Ethernet cabling. Fiber is also immune to electrical interference; there is no cross-talk between signals in different cables and no pickup of environmental noise. Non-armored fiber cables do not conduct electricity, which makes fiber a good solution for protecting communications equipment located in high voltage environments such as power generation facilities, or metal communication structures prone to lightning strikes. They can also be used in environments where explosive fumes are present, without danger of ignition. Wiretapping is more difficult compared to electrical connections, and there are concentric dual core fibers that are said to be tap-proof. Fiber optic sensors :- Fibers have many uses in remote sensing. In some applications, the sensor is itself an optical fiber. In other cases, fiber is used to connect a non-fiberoptic sensor to a measurement system. Depending on the application, fiber may be used because of its small size, or the fact that no electrical power is needed at the remote location, or because many sensors can be multiplexed along the length of a fiber by using different wavelengths of light for each sensor, or by sensing the time delay as light passes along the fiber through each sensor. Time delay can be determined using a device such as an optical time-domain reflectometer. Optical fibers can be used as sensors to measure strain, temperature, pressure and other quantities by modifying a fiber so that the quantity to be measured modulates the intensity, phase, polarization, wavelength or transit time of light in the fiber. Sensors that vary the intensity of light are the simplest, since only a simple source and detector are required. A particularly useful feature of such fiber optic sensors is that they can, if required, provide distributed sensing over distances of up to one meter. Extrinsic fiber optic sensors use an optical fiber cable, normally a multi-mode one, to transmit modulated light from either a non-fiber optical sensor, or an electronic sensor connected to an optical transmitter. A major benefit of extrinsic sensors is their ability to reach places which are otherwise inaccessible. An example is the measurement of temperature inside aircraft jet engines by using a fiber to transmit radiation into a radiation pyrometer located outside the engine. Extrinsic sensors can also be used in the same way to measure the internal temperature of electrical transformers, where the extreme electromagnetic fields present make other measurement techniques impossible. Extrinsic sensors are used to measure vibration, rotation, displacement, velocity, acceleration, torque, and twisting. Other uses of optical fibers:- Light reflected from optical fiber illuminates exhibited model Fibers are widely used in illumination applications. They are used as light guides in medical and other applications where bright light needs to be shone on a target without a clear line-of-sight path. In some buildings, optical fibers are used to route sunlight from the roof to other parts of the building . Optical fiber illumination is also used for decorative applications, including signs, art, and artificial Christmas trees. Swarovski boutiques use optical fibers to illuminate their crystal showcases from many different angles while only employing one light source. Optical fiber is an intrinsic part of the light-transmitting concrete building product, LiTraCon. Optical fiber is also used in imaging optics. A coherent bundle of fibers is used, sometimes along with lenses, for a long, thin imaging device called an endoscope, which is used to view objects through a small hole. Medical endoscopes are used for minimally invasive exploratory or surgical procedures (endoscopy). Industrial endoscopes used for inspecting anything hard to reach, such as jet engine interiors. In spectroscopy, optical fiber bundles are used to transmit light from a spectrometer to a substance which cannot be placed inside the spectrometer itself, in order to analyze its composition. A spectrometer analyzes substances by bouncing light off of and through them. By using fibers, a spectrometer can be used to study objects that are too large to fit inside, or gasses, or reactions which occur in pressure vessels. An optical fiber doped with certain rare earth elements such as erbium can be used as the gain medium of a laser or optical amplifier. Rare-earth doped optical fibers can be used to provide signal amplification by splicing a short section of doped fiber into a regular (undoped) optical fiber line. The doped fiber is optically pumped with a second laser wavelength that is coupled into the line in addition to the signal wave. Both wavelengths of light are transmitted through the doped fiber, which transfers energy from the second pump wavelength to the signal wave. The process that causes the amplification is stimulated emission. Optical fibers doped with a wavelength shifter are used to collect scintillation light in physics experiments Optical fiber can be used to supply a low level of power (around one watt) to electronics situated in a difficult electrical environment. Examples of this are electronics in high-powered antenna elements and measurement devices used in high voltage transmission equipment. USES:- Optical fibers are widely used in fiber-optic communications, which permits transmission over longer distances and at higher bandwidths (data rates) than other forms of communications. Fibers are used instead of metal wires because signals travel along them with less loss, and they are also immune to electromagnetic interference. Fibers are also used for illumination, and are wrapped in bundles so they can be used to carry images, thus allowing viewing in tight spaces. Specially designed fibers are used for a variety of other applications, including sensors and fiber lasers. Light is kept in the core of the optical fiber by total internal reflection. This causes the fiber to act as a waveguide. ADVANTAGES OF FIBRE OPTICS: We knowthe electrical signals travel pretty well in metal cables but nothing compares to light inoptical fibre. If we have to list the most outstanding advantages of using light as a carrier and optical fibres as transmission channels these may be some of them: Great bandwidth available to transmit information. You can easily use many GHz of bandwidth limitations being mostly related to electronics in the transmitters and the receivers. Low attenuation of the light travelling through optical fibres. Light can travel many kilometres in an optical fibre with little attenuation and without using amplifiers/repeaters or having them spaced a lot more than amplifiers in coaxial cables for example. Immunity to interferences. Optical fibres are made of glass not of any metal which makes them immune to any kind of electromagnetic interference. Galvanic isolation. Since they are not metallic they dont establish electrical contactbetween emitter and receiver nor create any capacitance along the length of the cable. REFERENCES:- http://en.wikipedia.org/wiki/Optical_fiber http://www.educypedia.be/electronics/cablingfibers.htm http://www.protelturkey.com/teknik/fo/IntroToFOMeas.pdf

Colonialism in India Essay -- British Invasion, Massive Boycotts

The British invasion formed into a historical development of British colonialism in India. Despite India under the British rule, Mahatma Gandhi played an important role in gaining Independence. He not only changed India but also strongly fought for India's independence, using various strategies. The British Empire ruled as long as they could to reform India both politically and socially. India was the first major Asian civilizations to fall victim to European predatory activities (Duiker 31). With conquering India, the British had various purposes behind it. Their main purpose was to achieve a monopolistic trading position (The Economic and Social Impact of Colonial Rule in India). The second purpose was the control of India; this was a key element in the world power structure, in terms of geography, logistics and military manpower (The Economic and Social Impact of Colonial Rule in India). When the East India Company continued to trade under the British, huge armies were created, largely composed of Indian sepoys (Marshall). The armies were used to defend the Company’s territories protect the Indian states (Marshall). With major control over India, the British used a combination of firepower & guile to consolidate their power over the country by expanding from their base areas along the coast into the interior (Duiker 31). Some territories were also taken over the privately run East India Company, which at the time was given authority to administer Asian territories under British occupation, while others were ruled by local maharajas (Duiker 31). British governance brought order and stability to a society that had recently been wrecked by the wars from the different empires (Duiker 31). Since the British wanted to refo... ...tween the Hindus and Muslims, Jinnah felt that Muslims had no future in India (Overfield 216). With the end of British rule in 1947, not only did India gain its independence but also along with it was born an other country, Pakistan where Jinnah served as the first governor (Overfield 216). With the gain of India’s independence, Gandhi was shot the following year in 1948 by a Hindu zealot who resented his commitment to Hindu – Muslim harmony (Overfield 212). Despite numerous conflicts with the British and with the Muslims, India fought for its rights by doing what they felt was right. India under the British rule had some benefits as the new school system and outlawing sati but they did manage to trouble the Indians with taxation and other laws. Gandhi who was an outstanding, important figure in India’s way for independence who taught to fight with nonviolence.

Greed - Vital to Human Welfare Essay -- Expository Essays

Greed - Vital to Human Welfare What's the noblest of human motivations? Some might be tempted to answer: charity, love of one's neighbor or, in modern, politically correct language: giving something back to the community. In my book, these are indeed noble motivations, but they pale in comparison to a much more potent motivation for human action. For me the noblest of human motivations is greed. I don't mean theft, fraud, tricks, or misrepresentation. By greed I mean people being only or mostly concerned with getting the most they can for themselves and not necessarily concerned about the welfare of others. Social consternation might cause one to cringe at the suggestion that greed might possibly be seen as a noble motivation. "Enlightened self-interest" might be a preferable term. I prefer greed since it is far more descriptive and less likely to be confused with other human motives. That human greed is the greatest of human motivations should be obvious to all; however, a few examples will make it more concrete. Texas cattle ranchers make enormous sacrifices to husband and insure the safety and well-being of their herds: running down stray cattle in the snow to care for and feed them, hiring veterinarians to insure their health, taking them to feed yards in time to fatten them up prior to selling them to slaughter houses. The result of these sacrifices is that New Yorkers can enjoy having beef on their supermarket shelves. Idaho potato farmers arise early in the morning. They do backbreaking work in potato fields, with the sun beating down on them and maybe being eaten by bugs. Similarly, the result of their sacrifices is that New Yorkers can also enjoy having potatoes on their supermarket shelves. Why do Texas cattl... ...ng an endangered species. Such a decree reduces the private use-value of the land and hence weakens incentives to care for the land. Similarly, if there were high transfer taxes for land sales, it too would weaken incentives to care for the land. In fact, anything that weakens the owner's private property rights in the land weakens his incentives to do the socially responsible thing - conserve on society's scarce resources. While human motivations such as charity, love, or concern for others are important and salutatory, they are nowhere nearly as important as people's desire to have more for themselves. We all know that but we pretend it is not. That unwillingness to acknowledge personal greed as vital to human welfare, and instead view it with disapproval, makes us easy prey to charlatans and quacks who'd take away our liberties in the name of combatting greed.

The Management of 21st Century: Hong Kong Essay -- essays research pap

Hong Kong is the most suitable place for business. It is characterized by its high degree of internationalization, business friendly environment, rule of law, free trade and free flow of information, open and fair competition. Therefore, the business management is a very important part in the business. The management of Hong Kong includes the external environment and the internal environment. The external environment includes the economic environment, labour market and social environment. In the economic environment, Hong Kong has faced the Asian financial turmoil in 1997. But now, the overall economic condition progressively improved. Later, China will be a member of the World Trade Organization (WTO). Hong Kong will gain a lot of business opportunity in different trades, such as banking, insurance, telecommunication. Those businesses need the new management for their future. For example, they must plan the new organization ¡Ã‚ ¦s goals, or they estimate the demand of human resources in the future. However, this phenomenon will disappear very soon when China would be a member of WTO after two years. It is because Hong Kong may not be the intermediate between China and the world since China will open their market for the world. Therefore, the Hong Kong companies may plan how to reduce the labour supply within an organization at that time. In the labour market, manpower is Hong Kong ¡Ã‚ ¦s most treasured asset. Because of much labour supply, it does no...

Comm/215 Persuasive

Technology Aaron Ivanovich Kevin Maevers November 16, 2010 As the world moves on, technology gets better and better. As we have all heard, technology is the future. Well if we continue down the path technology is setting for us then it might not be much of a future. Laziness is one of the huge problems that technology has brought about. Americas dependency on technology has left us crippled in a sense. When searching for a job for instance. You no longer even need to leave the house to apply for a job. Used to be you would have to go get a newspaper so you could browse through the job ads.Then you would have to go to the company in order to receive an application. Now you don’t ever have to step out of the house. You can wake up and take two steps to a computer and do it all online. It is more â€Å"convenient† for the employer as well. â€Å"all the employer has to do is put in a specific set of skills in a software, and the software does the rest. They do not have to read the resume† (Logan, 2010. P. 1). So in the end the employer never gets to meet a lot of the people applying unless their software matches them. In the end the computer system does a lot of the man hours that that specific employee would be doing.The employee still comes to work for the same amount of hours a day but sits around bored doing nothing most of that time. Computers cannot compute all factors of a person either though. At one time products were manufactured by people. Now almost everything you buy is done by a machine. Sure machines might be able to have a higher output but you lose the craftsmanship of a product. â€Å" There is more value placed on the quantity of things that we can do, rather than the quality of our output† (Freyda, 2010. Para. 2). Higher output means more money. Less workers, more machines, means more money.When did producing a good product go out the window. People are now even to lazy to build things on our own. We need a machine t o do it for us at a more efficient rate. America is one of the most obese nations right now. Technology is a big part to blame for that situation. â€Å"The washing is done automatically, meals can be cooked in the microwave at the press of a button, mobile phones allow us to send instant messages, the internet lets us see family and friends in other countries, and while this all takes place the obesity crisis escalates† (Waldron, 2010. Para. 2).There is no way that this is a coincidence. Since you do not have to leave the house anymore to do anything, people don’t. just getting out and walking to the mailbox to send out a letter is some exercise. â€Å"You can go shopping by seat of your comfy computer chair† (Logan, 2010. P. 1). Even grocery shopping has become an online task. In theory this should free more time up for people so they could go for a run a run or hit the gym. But like I said, in theory. By using these systems people have become dependant and la zier. They don’t want to leave the house for anything.They sit around and find new ways to get out of everyday tasks that require you to go outside. You cant say that technology is the bad guy here though. In such fields as medicine for example. New breakthroughs in technology are keeping people alive. Finding new cures and safer operations. Plus, â€Å" there’s a saying that goes â€Å"don’t work harder†¦ work smarter†. I believe that’s what technology allows us to do and disguises itself as laziness† (GlahES, 2007. Para. 3). The ultimate goal in creating technology is to make hard, strenuous tasks into simple ones. This provides less work for people so in turn makes them look lazy.So in the end what I am trying to say is that technology is making us lazy. It makes tasks to easy to accomplish. There is no more pride in a job well done. No overwhelming feel of accomplishment because we didn’t really even complete anything. We wat ched a machine do it. Staying in shape was not necessarily a chore either. Going to work and doing your job was exercise. You were moving around all day, not just standing there. You should not hate technology though. It is not the whole problem. People are the problem really, we need to realize not to rely on technology for everything.RESOURCES Freyda, T. 2010, Month Day). Is Technology Making us Lazy? []. Message posted to http://www. helium. com/items/1611489-technology-is-making-us-lazy GlahES, . (2007, Month Day). Technology: creating lazy or smart humans? , []. Message posted to http://www. abovetopsecret. com/forum/thread312869/pg1 Logan, T. (2010, Month Day). Is Technology Making us Lazy? []. Message posted to http://www. helium. com/items/1673497-is-technology-making-us-lazy Waldron, R. (2010, Month Day). Is Technology Making us Lazy? []. Message posted to http://www. helium. com/items/1779365-technology-is-technology-making-us-lazy? page=2