Data Communications Essay Example for Free

Data Communications Essay Differentiate between an analog and a digital electromagnetic signal. What are three important characteristics of a periodic signal. What is the relationship between the wavelength and frequency of a sine wave. Define fundamental frequency. What is the relationship between a signals spectrum and its bandwidth. What is attenuation? Define channel capacity. What key factors affect channel capacity? Problems: Figure 1 shows the frequency domain function for a single square pulse. The signal pulse could represent a digital 1 in a communications system. Note that an infinite number of higher frequencies of decreasing magnitudes is needed to represent the single pulse. What implication does that have for a real digital transmission system? Suppose that a digitised TV picture is to be transmitted from a source that uses a matrix of 480 x 500 picture elements (pixels), where each pixel can take on one of 32 intensity values. Assume that 30 pictures are sent per second. (This digital source is is roughly equivalent to broadcast TV standards that have been adopted.) Find the source rate R (bps) Assume that the TV picture is to be transmitted over a channel with 4.5Mhz bandwidth and a 35dB signal-to -noise ratio. Find the capacity of the channel (bps). Discuss how the parameters given in part (a.) could be modified to allow transmission of colour TV signals without increasing the required value for R. What is the channel capacity for a teleprinter channel with a 300Hz bandwidth and a signal-to-noise ratio of 3dB, where the noise is white thermal noise? A digital signalling system is required to operate at 9600bps. If a signal element encodes a 4-bit word, what is the minimum required bandwidth of the channel? Repeat part (a .) for the case of 8-bit words. Given the narrow (usable) audio bandwidth of a telephone transmission facility, a nominal SNR of 56dB (400,000), and a certain level of distortion, What is the theoretical maximum channel capacity (kbps) of traditional telephone lines? What can we say about the actual maximum channel capacity? Given a channel with an intended capacity of 20Mpbs, the bandwidth of the channel is 3MHz. Assuming white thermal noise, what signal-to-noise ratio is required to achieve this capacity? If an amplifier has a 30dB voltage gain, what voltage ratio does the gain represent? An amplifier has an output of 20W. What is the output in dBW? Answers: Short Questions With guided media, the electromagnetic waves are guided along an enclosed physical path whereas unguided media provide a means for transmitting electromagnetic waves but do not guide them. A continuous or analog signal is one in which the signal intensity varies in a smooth fashion over time while a discrete or digital signal is one in which the signal intensity maintains one of a finite number of constant levels for some period of time and then changes to another constant level. Amplitude, frequency, and phase are three important characteristics of a periodic signal. The relationship is ÃŽ »f = v, where ÃŽ » is the wavelength, f is the frequency, and v is the speed at which the signal is traveling. The fundamental frequency is the lowest frequency component in the Fourier representation of a periodic quantity. The spectrum of a signal is the frequencies it contains while the bandwidth of a signal is the width of the spectrum. Attenuation is the gradual weakening of a signal over dis tance. The rate at which data can be transmitted over a given communication path, or channel, under given conditions, is referred to as the channel capacity. Bandwidth, noise, and error rate.

Gene Krantz Leadership Case Study

Gene Krantz Leadership Case Study According to many theories and best practices, leadership extensively affects the organisational performance. Moreover, many studies suggest that leadership is either a trait (e.g. Stogdill, 1974) or driven by behaviour ( e.g. Shamir and Howell, 1999). In our assessment of Krantzs leadership role Traits theory In Apollo 13, elements of traits related to leadership was included and strongly demonstrated by Krantz with a compelling vision and strong culture. This included seven values: drive, desire to lead, honesty and integrity, emotional maturity, and intelligence. However, integrity was found to be a superordinate value without having the other values far less significance. Given the stress and contiguity of the Apollo 13 crisis, it is noticeable that the traits of a true leader differ depending on time and context. (Ahn, Ettner, and Loupin, 2012) Drive Krantz was perceived as highly driven and capable of prioritising and communicating issues and needs during unsettled situations as he provided guidance and psychological safety for his team members. (McDermott, Kidney, and Flood, 2011). He was also directing the actions of the team towards a specific goal of getting the astronauts safely home. Desire to lead and good judgment Krantz has a distinctive desire to lead with effective decision making which was far more about accumulated wisdom he had but more of him building an open environment with openness, accountability and honesty (Sonnefield, 2002) Honesty and integrity Integrity can be explained as the unwavering devotion to a specific ethical or moral value. (Ahn, Ettner, and Loupin, 2012). The significance of integrity of Krantz towards the Apollo 13 crisis was essential even when the team was devastated he ensured that all obligations are met to work on the astronauts safe journey home. Self Confidence It is the leaders awareness of his/her inner-competencies. This includes self- assurance and self-esteem that s/he can make a difference. This allows the leader to influence others effectively in the appropriate and right ways. This characteristic affects attitudes; tendencies and emotional influence to others. (Belasen and Frank, 2008) Again, Krantz was a very self-confident leader. When he described that they will not fail in bringing the astronauts safely back home although his team thought it was impossible. But he never doubted that the mission will be accomplished successfully, and despite the resistance of many team members, he did things the way he thought best. Emotional Maturity Krantzs emotional intelligence had a great impact for his leadership role. According to ( Mayer and Salovey,1997) it is the skill to connect or disconnect from emotions relying on the efficiency of emotions in a specific situation. And Krantz demonstrated that clearly by engaging in his self- reflection which enabled him to contribute to a stronger sense of self identity and understanding his team and their actions. (McDermott, Kidney, and Flood, 2011) Intelligence Gene Krantz is an intellectual leader but his IQ was not higher than his followers. But he had strong perceptional, reasoning and verbal abilities which lead to a productive outcome as he didnt have any difficulties communicating with his subordinates. Job Related Knowledge Not only Krantz the engineer -had the job related knowledge as he was a flight director for many years, but also the ability to learn from his subordinates experiences and applied that learning to new and different situation. He was able to derive meaning from all kinds of experience in the NASA team with his learning agility -which is different from basic intellect- according to the changing circumstances during the crisis. (Povah, 2012b) Determination A sense of urgency was clearly identified by Krantz during the Apollo 13 crisis which gave the capacity to impart an action- orientation towards achieving results. He has the desire to get the job done as he was persistent and dominant. He battled against pessimism and focused on solving the problem despite all obstacles faced them. He was proactive with his team but still directing his team to achieve the goal. Trust Integrity Competence Conisistency Loyalty Openness Leadership Behaviours Style The leadership Style Krantz used was more Democratic rather than Autocratic or Laissez-Faire Style. He listened to his team and encouraged different point of views. However, there was a time limitation to do more analysis. Krantz pulled one flight control team out of its normal role to work on solutions for the crisis. He moved staff from team to team to bring specific skills, knowledge and expertise. He kept directing them towards the goal as his leadership was the key factor of successfully accomplish the mission although it was considered the successful failure. Managerial/Leadership grid (Blake and Mouton) One of the most well-known approaches to leadership The Managerial Grid developed by Robert Blake and Jane Mouton (1964) was used to analyse the leadership style of Krantz. He had to achieve the goal of getting the astronauts safely back home (Task) and at the same time, manage his team (People). His main concern was to ensure that his subordinates get the job done without failure based on obedience, trust, respect and support. His team was responding with involvement and enthusiasm. Using the grid which forms a matrix of possible leadership styles to analyse how he used his skills and intelligence in working with and through other people for results as shown in Figure 1. (Sui Pheng and Lee, 1997) Figure 1.1: Krantzs Leadership style associated with Managerial Grid Source: (Sui Pheng and Lee, 1997)   Ã‚   According to the managerial Grid, Krantz was an effective team leader. He was contributing to the crisis and committed to getting the job done. Although he was concerned about the result of getting astronauts back home and pushed his subordinates to the limit, he was motivating the team while empowering them with trust, respect and commitment. This sound leadership style is also inspired by the McGregor Y theory. Situational Approach Fiedlers Contingency Model Leader- Member exchange theory Authentic Leader Transformational Leadership Apollo 13 movie told the story of a crisis that could have ended tragically. It required transformational leaders to articulate a clear vision that would allow the constituents to take on leadership roles based on their experiences, needs, values, morale and strengths. Through innovation and creative problem solving they were able to collaboratively work towards their new vision to getting the astronauts home safely. This was successfully achieved as the leaders used idealised influence, inspirational motivation, intellectual stimulation and individual consideration to lead constituents through this catastrophe. In summary, this report reflects the leadership demonstrated in Apollo 13 using many leadership theories. Our use of the Leadership Trait Theory, Situational Leadership and leadership grid provided a more behaviour- specific focus on interpersonal skills concepts.  

Literary Comparison Of A Clock Essay -- essays research papers

A Literary Comparison Of A Clockwork Orange and The Crucible   Ã‚  Ã‚  Ã‚  Ã‚  The existence of evil in the world is a universal question that is often contemplated. Anthony Burgess and Arthur Miller in their novels A Clockwork Orange and The Crucible address this question of evil. One of these stories is set in the future, and the other in the past confirming the belief that the human struggle between good and evil is timeless and applies to every person in society. Throughout history numerous examples of leaders have attempted to control the nature of people within their society through systems of punishment and reward. This system had failed continuously to control the entire population because people still retain their ability to choose. It is said that once a person loses his free will, he ceases to be a person. This is the struggle confronting the protagonists in both A Clockwork Orange and The Crucible. The fifteen-year old rebel Alex and the respected farmer John Proctor refuse to conform to the rules of their oppressive societies, a nd as a result are denied the freedom to choose between good and evil, therefore becoming less than human.   Ã‚  Ã‚  Ã‚  Ã‚  Both Alex and John Proctor live in highly oppressive societies from which they feel alienated, and therefore decide to rebel against. The futuristic setting of A Clockwork Orange is one of a constructive, depersonalized society where the government has far too much control over people’s lives. They are forced to live in strictly regimented communities, and their daily life is dreary. “Alex’s England is a socialized nightmare.'; (De Vitis, 106) It is because of this meaningless life that Alex chooses to rebel against his society, committing so many brutal acts of violence that he soon becomes desensitized to the horror he is creating. When questioned by his correctional officer as to why he acts this way, Alex replies “…badness is of the self, the one, the you or me. They of the government and the judges and the schools cannot allow badness because they cannot allow they self… what I do, I do because I like to do it. (Burgess, 34 ) Alex fully Bisson 2 realizes that the controlled society he lives is one that tries to eliminate all individuality. This causes him to act out in violence against authority as a means o... ... since it is the only way he will be allowed to remain true to himself. Proctor realizes that life without free will is a subhuman existence and not worth living. Both Alex and john, unable to choose between right and wrong for themselves, cease to have a normal existence, and both choose death over a life without choice. This is the only way they have of affirming their humanity.   Ã‚  Ã‚  Ã‚  Ã‚  Both Anthony Burgess and Arthur Miller believe that it is more important to remain true to oneself then to always choose good over evil. They show a person must maintain their free will in order to function properly as a human being. They prove this in their works A Clockwork Orange and The Crucible by showing the negative things which befall the protagonists when their right to choose is taken from them. Basically, a free will is essential to every human being, and to take it away is to dehumanize an individual. The two novels function as notable warnings to those that would sacrifice their individuality to please authorities. In addition, they remind the reader that what makes a person is their ability to choose, and so it is necessary that people be allowed that choice.

The Characters of Tennessee Williams A Streetcar Named Desire :: A Streetcar Named Desire Essays

The Characters of A Streetcar Named Desire  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   Tennessee Williams was one of the greatest American dramatists of the 20th century. Most of his plays take us to the southern states and show a confused society. In his works he exposes the degeneration of human feelings and relationships. His heroes suffer from broken families and they do not find their place in the society. They tend to be lonely and afraid of much that surrounds them. Among the major themes of his plays are racism, sexism, homophobia and realistic settings filled with loneliness and pain.1 Tennessee Williams characters showed us extremes of human brutality and sexual behavior.2   One of his most popular dramas was written in 1947, and it is called A Streetcar Named Desire.   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   The drama is basically about a married couple -Stella and Stanley Kowalski- who are visited by Stella's older sister, Blanche. The drama shows the caustic feelings of these people putting Blance DuBois in the center. The drama tells the story of the pathetic mental and emotional demise of a determined, yet fragile, repressed   and delicate Southern lady born to a once-wealthy family of Mississippi planters.3   No doubt that the character of Blanche is the most complex one in the drama. She is truly a tragic heroine.   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   First she is introduced as a symbol of innocence and chastity.4   She is aristocratic and intelligent, and sensitive and fragile at the same time, also beautiful and this delicate beauty has a moth-like appearance. But these positive characteristics are overshadowed by the fact that Blanche arrives to Elysian Fields, which is a poor section of New Orleans, on two streetcars, Desire and Cemeteries. These misterious expressions, which can be considered to be the main symbols of the play, suggest that something is is not clear around Blanhe or that something wrong will happen towards the end. Elysian Fields symbolizes paradise beyond death from ancient lore,3   Desire expresses Blanche's desire to be loved and Cemeteries represents her fear of death.4   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚     Ã‚  Blanche represents a deep-seated attachment to the past.5   Her life is a lesson how tragic events events in the past can ruin a person's future. Her husband's death affects her the most. Blanche was only a young girl without any experience when she got married. She married Allan Grey, who was only sixteen. Their marriage started well, but later the young wife found out that Allan was homosexual.

Japan Essay -- Geography Geographical Japan Essays

Japan Geographical Setting Japan is an island country in the North Pacific Ocean. It lies off the northeast coast of mainland Asia and faces Russia,Korea, and China. Four large islands and thousands of smaller ones make up Japan. The four major islands- Hokkaido,Honshu,Kyushu and Shikoku form a curve that extends for about 1,900 kilometres. Topography Japan is a land of great natural beauty. mountains and hills cover about 70% of the country. IN fact, Japanese islands consist of the rugged upper part of a great mountain range that rises from the floor of the North Pacific Ocean. Jagged peaks, rocky gorges, and thundering mountain waterfalls provide some of the country's most spectacular scenery. Thick forests thrive on mountansides, adding to the scenic beauty of the Japanese islands. Forests cover about 68% of the country's land. Japan lies on an extremely unstable part of the earth's crust. As a result, the land is constantly shifting. This shifting causes two of Japan's most striking features-- earthquakes and volcanoes. The Japanese islands have about 1500 earthquakes a year. Most of them are minor tremors that cause little damage, but severe earthqaukes occur every few years. Underseaquakes sometimes cause huge, destructive tidal waves, called tsunami, along Japan's Pacific coast. The Japanese islands have more than 150 major volcanoes. Over 60 of these volcanoes are active. Numerous short, swift rivers cross Japan's rugged surface. most of the rivers are too shallow and steep to be navigated. Their waters are used to irrigate farmland, and their rapids and falls supply power for hydroelectric plants. Many lakes nestle among the Japanese mountains. Some lie in the craters of extinct volcanoes. A large number of hot springs gush from the ground throughout the country. The Japanese islands have a total land area of about 337,708 sqkm. The islands , in order of size, are Honshu, Hokkaido, Kyushu and Shikoku. The sea of Japan washes the country's west coast and the Pacific ocean lies to the east. Climate Regional climates in Japan can be compared to those of the East Coast of the United States. Kyushu and Shikoku have a climate much like that of Perth. They have long hot summers and mild winters. The island Honshu's generally has warm,humid summers. Winters are mild in the south and cold and snowy in the n... ...ies of the language for use in different social contexts; these varieties are called social styles of speech. A large number of dialects are spoken throughout Japan's four main islands (Hokkaido, Honshu, Shikoku, and Kyushu), as well as on the smaller islands, such as the Ryukyu Islands. Some dialects-for instance, those spoken in the southern parts of Japan, notably on the islands of Kyushu and Okinawa-are virtually incomprehensible to the speakers of other dialects. As a result of this diversity of dialects, the Japanese use a standard, or common, dialect to facilitate communication throughout the country. The two dialect families with the largest number of speakers are the dialect spoken in and around Tokyo, which is the common dialect, and the dialects of the Kansai region in western Japan, spoken in cities such as Kyoto, Osaka, and Kobe. Due to the spread of the common dialect through television and radio, most people outside the Tokyo region speak the common dialect as well as a local dialect. Refrences: World Book Encyclopedia (Cd Rom) Grolier Encyclopedia (Cd Rom) Encarta 96 Encyclopedia (Cd Rom) JETRO (Internet Site) CIA World Factbook (Internet Site)

The Significance of Adult Education

Adult education encompasses planned and organized activities that consists of classes, lecture series, group study and systematic discussions and conference which involves mature men and women acquire new knowledge, understanding, attitudes, interests and values as a means of adapting and coping up with dramatic changes happening in the modern society and environment. It is dedicated to learning improvement and extension of opportunity for adults (encyclopedia Americana). Adult education is a form of continuing education that serves as a way of expanding horizons, developing understanding, creating meaningful activities and bridging the gap between generations. It has a critical role in a rapidly changing world by providing information and knowledge that people need in dealing with changing conditions. It is of great help in perceiving and solving crucial issues of the times. It can be a tool also for sustaining social relationship among aged adults. Adult education is the practice of teaching and educating adults. Adult education takes place in the workplace, through ‘extension' or ‘continuing education' courses at secondary schools, or at colleges or universities. Other learning places include folk high schools, community colleges, and lifelong learning centers. The practice is also often referred to as ‘Training and Development ‘and is often associated with workforce or professional development. It has also been referred to as andragogy (to distinguish it from pedagogy). Adult education is different from vocational education, which is mostly workplace-based for skill improvement; and also from non-formal adult education, including learning skills or learning for personal development. Programs provide one to one tutoring and small group sessions for adults at the 6th grade level or below. Public libraries, nonprofit organizations and school systems administer these programs across the country. Many adult education centers from community colleges receive grants from Welfare and Unemployment departments to offer training to welfare and unemployment recipients to help these individuals gain life and work skills to facilitate their return to the mainstream. They also provide programs for ex-offenders to reintegrate to society. There are underlying factors and forces which paved way for the development and improvement of Adult education. Changes in technological processes, in communication, in knowledge in social organization and in patterns of living implies that a modern man must constantly learn new ideas, new facts, new skills and new attitudes to keep up with the progress of the society. Through this kind of formal literacy education, adults develop the sincerity and aim to learn those things they need to know in order to cope effectively with the real life situation. Adult education is simply a continuation and way of improving prior knowledge of matured individuals. It believes and wanted to prove that adults are pragmatic learners. Adults frequently apply their knowledge in a practical fashion to learn effectively. They must have a reasonable expectation that the knowledge recently gained will help them further their goals. One example, common in the 1990s, was the proliferation of computer training courses in which adults (not children or adolescents), most of whom were office workers, could enroll. These courses would teach basic use of the operating system or specific application software. Because the abstractions governing the user's interactions with a PC were so new, many people who had been working white-collar jobs for ten years or more eventually took such training courses, either at their own whim (to gain computer skills and thus earn higher pay) or at the behest of their managers. Adults by social definition, individual need, and institutional expectation are responsible people that seek to enhance their identity through learning that further develop their competence. They have a strong need to apply what they have acquired and in order for them to be competent in that application, there is a reciprocal needs of interaction between them and the rapidly changing environment to produce a powerful desire for more knowledge.

Exams Should Be Abolished Essay

Exams – a word that many students dread to hear, a word that many students fear of, a word that seems to have the magical power to transform a happy and cheerful person into a frustrated and nervous wreck. What are exams and should they been done away with entirely? Exams are longer and more comprehensive versions of tests held every term. Initially created to monitor and check how a student was performing academically, they now have so much more pressure on them that students are burning the midnight oil to study for an exam. This results in some students becoming ill due to stress and lack of sleep. They have become more and more stressful and, even worse, a constriction to the ideal of learning. It is a well known fact that when it comes to exams, students compete, not only with themselves, but with other students. They no longer want to see an increase in their knowledge, but want to beat other people to the top of the class. Even parents take exams as a race to see whose children are more intelligent. Read more: If There Were No Exams Students shouldn’t be judged on their performance on one day when they might be ill. The exams might not be completely representative of the student’s skills as everyone can have a bad day. They are a poor method of assessment as they don’t reflect the use of knowledge in a practical environment. They don’t reflect how well you’ll be able to use your knowledge in real world occupations. Many successful individuals are bad at exams but can perform well under other methods of assessment such as essays and oral presentations which still prepare students in coping with pressure. Some people would argue that exams are not a fair assessment of intelligence and aren’t favourable to those with poor memory skills, those who suffer under pressure, and those who get so nervous in such situations that they shut down in exams. It’s  very easy to know content but to completely fail an exam because you are nervous. They aren’t an accurate representation of a student’s knowledge as some people are just better at taking exams than others. If you happen to mess up in your exams due to stress or panic then your goals can disintegrate leaving you unable to reach your full potential and having to settle for second best.