Environmental Pressures Essay Example for Free

Environmental Pressures Essay All companies have moments of growth and decline. As companies age, change in the form of growth is brought about (Palmer, 2009, p.65). Companies look for the increases in revenue and ways to create more revenue. When money is being made growth happens, new jobs are created, expansions begin and technology is heightened. Last week Time Warner Cable announced that there will be a new CEO, as the current CEO, Glenn Britt will be retiring. The new CEO, Rob Marcus talked about the growth pressures concerning Time Warner Cable. Mr. Marcus emphasized the growth potential of selling data services to businesses, which is the fastest-growing sector of the cable industry. He also said Time Warner Cable is working to improve pricing and packaging and is hoping to retain customers by improving products like outdoor Wi-Fi. Identity Pressures Identity Pressures basically deals with the way a company brands themselves. Time Warner Cable brands themselves as a reputable and customer based oriented company. Time Warner Cable is dedicated to making their brand number one in the fields of cable, high speed data and telephony services. A commitment is given to customers to provide them with the best products and services they have to offer. Dish, satellite and ATT U-Verse attempt to compete, but when it comes to quality service, products and the commitment given to the consumers there is no better way to for the company’s identity to be missed. New Broom Pressures Time Warner Cable’s adds new members to the team that attempt to make changes bit it is not necessarily for the better. In the HR Department this past year a new VP was hired and due Environmental PressuresPage 3 to some of her background being shared before she arrived, people began looking for other jobs, all the supervisors that were in place when I was promoted a year and a half ago, have left the company in order not to work under her. There are many people that are not ready for change. Under the new VP, a lot of changes have taken place when the department all for the better of the department. Everything is a work in progress however, the  necessary changes that were needed have been implemented and work has become a great deal easier. Market Decline Pressures Time Warner and AOL were once partnered to together, it appeared that AOL was in a trend of continuous growth, however AOL began to suffer a decline in 2002 due to the pricing of broadband services being charged at $50.00 per month and consumers not wanting to pay that much for broadband services. A need for strategic changes by AOL, including partnering with cable companies and other options that move it away from overreliance on dial-up services, (Palmer, 2009). AOL eventually began providing free services there are still some customers that pay for AOL services plus the benefits they receive for using the technical department of AOL if needed. Hyper-competition Pressures Within my company, hyper-competition forced them to move quickly and audaciously to test their policies and theories. Time Warner Cable decided to change the way they did business when they branched out on their own from Time Warner Cable, Inc. Hyper-competitive can have dynamic and unpredictable environments which requires flexibility, innovation and a creative organization, which can easily adapt quickly to the changing rules of competition. Therefore, Time Warner Cable needed to change and management was pertinent to that change. What was Environmental PressuresPage 4 Challenging to management was how they would combine the need for long-term sustainability with continuous flexibility in terms of how the organization technology would change if at all. Time Warner Cable needed to develop a high degree of dynamic capabilities, which was the center of meeting the tensions of the capability and structural challenge. The organizational aspects and capabilities goes hand in hand as enabler and at the same time facilitate a successful emergent change process in hypercompetitive industries. Flexibility Flexibility can be a reason for changes in the competitive environment in an appropriate and timely way. Flexibility comes from managerial capabilities  (management challenge) and the responsiveness of the organization (organization design challenge).Flexibility requires a constructive discord between change and preservation. Strategic flexibility is an increasingly sought-after competitive element in today’s fast-paced and changing world. (Englehardt, 2002) Reputation and Credibility Pressures Time Warner Cable has pride in their reputation. A company’s reputation can be damaged at the drop of a dime. All it takes is an unsatisfied customer to speak negatively about a company or bring up a potential law suit against a company. Time Warner Cable has a team legal team staffed in house at Corporate however, all attempts are made on the lower levels to diffuse the situation before it gets that far. It a company’s reputation is ruined, there is serious backlash from it, the company loses customers, hence revenue, potential job loss can occur and worst of all the company doors can close. Reputation can be in formation of customer loyalty (Nguyen, 2001). Credibility is major, if consumer cannot count on a company to do what it is Environmental PressuresPage 5 they say they are going to do, consumers will go else and not mind paying a higher rate to get what they want. Customers want to know that the companies / organizations are trustworthy and they can count on them to be there and provide them with the services and products they want. Environmental and Organizational Pressures that exist Time Warner Cable has and does face environmental pressures on a daily basis. There is constant pressure to change strategies. Time Warner Cable is continuing to engage in new markets, corrections of internal issues are made. Basically everything is controllable it may take a little while but things are normally resolved in a 24-48 time period at the latest a 5 day period. One thing that Time Warner Cable has learned as a company is that with organizational change, there may or may not be an innovational change. Financial Perspective From a financial perspective concerning environmental and organizational pressures, things could go either way, we try to predict the way things will work out from a financial view point but the economy plays a major role. Consumers are becoming very careful with their spending. If thing begin to look bleak the finances go down. When the market is going well and profits are in the upswing then finance is great. Environmental and Organizational Pressures Impact The environmental and organizational pressures have impacted me personally as it affected my bonus this past year. I have received bonuses a great deal higher than what I received this year. I was slightly disappointed but still happy to receive a bonus all the same. Part of the bonus is based upon 80% what the company does and 20% is based upon performance. My performance was great, the company did well be not as well as in previous years. Environmental Pressures Page 6 Assessing how the organization has reacted to the organizational and environmental pressures Time Warner Cable’s reaction to organizational and environmental pressures are to regroup, see what we can change and do it better and how can we as an organization best serve our customers. By going back to the drawing board, great emphasis is placed on training, management strategizes on how to best retain current customer and how to gain new customers and customers and providing customers with the latest and greatest products, services and technology available. Time Warner is focusing on customer satisfaction. Reducing Environmental and Organizational Pressures One way Time Warner Cable can reduce their risk is by nurturing their responses when it becomes a little chaotic the pressure may appear to be small but it is all in the way the company decides to handle things. Reduction can be made concerning with organizational pressures by paying close attention to growth pressures. The potential growth of a company can helpful but it is necessary to hire smart. Strategies One strategy I would propose is for Time Warner Cable would be to listen to their customers and their employees. By listening to their customers better  offers and campaigns can be built in order to give them customers what they are asking for. Listening to the employees will help to bring about better services for their employees health and welfare. Environmental PressuresPage 7 Reference Charles S. Englehardt, Peter R. Simmons, (2002) Organizational flexibility for a changing world, Leadership Organization Development Journal, Vol. 23 Iss: 3, pp.113 121 Nha Nguyen, Gaston LeBlanc, (2001) Image and reputation of higher education institutions in students’ retention decisions, International Journal of Educational Management, Vol. 15 Iss: 6, pp.303 – 311 Palmer, I., Dunford, R., Akin, G. (2009). Managing organizational change: A multiple perspectives approach (2nd ed.). New York: McGraw-Hill.

The aim of my experiment Essay Example for Free

The aim of my experiment Essay Evaluation Although I feel that my experiment was sound overall, I thought there were many points at which the accuracy was not perfect. As I have already stated, my preliminary experiment was not accurate enough to justify being used as my main experiment, mostly due to the fact that I was relying on all the bubbles being the same size, which they clearly werent, however many of the smaller inaccuracies also apply to my main experiment. Firstly, the distance between the light sources and the Canadian Pondweed were not measured to a very high degree of accuracy, especially when you note the fact that the distance should have been measured exactly from the filament of the light bulb to the centre of the plant, and it is possible here to find a percentage error. I estimate that the error could have been up to 0. 5cm and I will find the percentage error for the largest and smallest reading using this estimate: Percentage error = possible inaccuracy total reading % error distance 10 5cm 1 50cm It is clear to see that the percentage error is much less for the larger distances. Although I was not actually using the distances as part of my results, I used them as a marker for where the lamp was placed each time, as I assumed that the light intensity would be the same each time at a particular distance. Therefore, any inaccuracies in measuring the distances, i. e. if a distance was slightly different when doing the actual experiment from the distance at which I earlier measured the light intensity, an error would ensue. The second major inaccuracy was in measuring the volume of oxygen given off. When reading the syringe there could have been an error of 0.25mm, and again it is possible to find a percentage error. % error volume 3. 57 7ml 50 0. 5ml For the smallest volumes this is clearly a massive error, and to improve this, it would be necessary to do the readings over a longer period of time, therefore increasing the volumes, and in turn reducing the percentage errors. Another error would have been due to background light in the vicinity. We tried to reduce this error by closing all blinds in the laboratory, but due to practical reasons, we could not all perform the experiment in a separate room, and we therefore experienced light pollution from other students experiments. This would have had a very marginal effect on my results as a whole, but to eliminate this problem completely, it would have been necessary to perform the experiment in a totally dark room. A further inaccuracy was in the heat generated by the lamp. As I have earlier described, temperature has a very noticeable effect on the rate of photosynthesis, and so any increase in the temperature of the pond water would have had serious effects on the accuracy of my results. To ensure this did not happen, I monitored the temperature of the water before and after every reading, to check that the temperature did in fact not rise. It turned out not to be a problem, as over the short period of time taken by my experimental readings, the temperature did not rise at all. However, if I were to extend the time of my experiment to 5 minutes for each reading for example, which would have the effect of reducing other percentage errors, I would have to find some way of keeping the temperature constant. One way of doing this would be to place a perspex block between the lamp and the plant, which would absorb most of the heat, while allowing the light energy to pass through. As I mentioned in my planning, carbon dioxide concentration could have been an error in the experiment, however, I feel that due to the short period of time taken, there is very little chance that the concentration would ever have been so low as to have become the limiting factor. Again if I were to carry out the experiment over a longer time period, it would have been necessary to add sodium hydrogen carbonate to the water to increase the carbon dioxide concentrations. The last inaccuracy, though a small one, was in the time keeping. The main problem here was in when to begin the minute. If for one reading, the minute was started just after one bubble had been produced, and in another reading it was just before, this could have had a negative effect on the accuracy of my results. I therefore ensured that in each case I started the stopwatch just after a bubble had been produced, thus heightening the accuracy. Overall, I felt that due to the small volumes of oxygen involved, my experiment was not as accurate as it could have been, however I believe it was accurate enough to support and justify my hypotheses. Improvements could have been made as I have stated, mainly by simply increasing the time taken. However, due to practical time constraints in taking the readings for my investigation, and some consequential problems relating to time extension, I could not in fact make these adjustments. The other obvious way of increasing the reliability of my results would be to take many repeat readings and find an average. To extend my enquiries into the rate of photosynthesis, I could perhaps try to link in some of the other limiting factors to the same experiment, as well as investigating them in their own right. It could also be interesting to explore the effects of coloured lights on the rate of photosynthesis, which could lead to the question of whether or not other types of light, such as fluorescent lights or halogen lights, would have a different effect on the rate of photosynthesis.

Application Of EM Waves In Satellite Communication Computer Science Essay

Application Of EM Waves In Satellite Communication Computer Science Essay This paper deals with the historical development of satellite communication systems. Then the basic elements of satellite communication system along with their features are discussed. Then the working of a satellite communication system and the use of EM waves in this system is discussed and then finally the applications, advantages and limitations of satellite communication system are discussed. Introduction Electromagnetic wave is a wave of electric and magnetic field components which oscillate in phase perpendicular to each other and perpendicular to the direction of energy propagation. Generally, EM radiation (the designation radiation excludes static electric and magnetic and near fields) is classified by wavelength into radio, microwave, infrared, the visible region we perceive as light, ultraviolet, X-rays and gamma rays..The behaviour of EM radiation depends on its wavelength. Higher frequencies have shorter wavelengths, and lower frequencies have longer wavelengths. Spectroscopy can detect a much wider region of the EM spectrum than the visible range of 400  nm to 700  nm. Electromagnetic waves as a general phenomenon were predicted by the classical laws of electricity and magnetism, known as Maxwells equations. If you inspect Maxwells equations without sources (charges or currents) then you will find that, along with the possibility of nothing happening, the theory will also admit nontrivial solutions of changing electric and magnetic fields. Any electric charge which accelerates, or any changing magnetic field, produces electromagnetic radiation. Electromagnetic information about the charge travels at the speed of light. Accurate treatment thus incorporates a concept known as retarded time. At most wavelengths, however, the information carried by electromagnetic radiation is not directly detected by human senses. Natural sources produce EM radiation across the spectrum, and our technology can also manipulate a broad range of wavelengths. Fig. 1 electromagnetic spectrum Satellite Communication A satellite is a physical object that orbits or revolves around some celestial body. In general satellite is an artificial satellite stationed in space for the purposes of communication, military, surveillance, etc. A satellite communications (sometimes abbreviated to Comsat) is an artificial satellite stationed in space for the purposes of telecommunications using microwave frequencies. Most communications satellites use geosynchronous orbits or near geostationary orbits, although some recent systems use low Earth-orbiting satellites. Communications satellites provide a technology that is complementary to that of fibre optic submarine communication cables. Unlike fibre optic communication, satellite communication has a propagation delay (also called a path delay) of at least 270 milliseconds, which is the time it takes the radio signal to travel 35,800 km from earth to a satellite and then back to earth. Satellite Internet connections average a 600-800 millisecond delay, about ten times than that of a terrestrial Internet link. This delay is a challenge to deployment of Virtual private networks over satellite internet connections. HISTORY OF SATELLITE COMMUNICATION The concept of satellite communications was first proposed by Arthur C. Clarke, based on Herman PotoÄ niks pseudonymous work from 1929. In 1945 Clarke published an article titled Extra-terrestrial Relays in the magazine Wireless World. The article described the fundamentals behind the deployment artificial satellites in geostationary orbits for the purpose of relaying radio signal. Thus Arthur C. Clarke is often quoted as the inventor of the communications satellite. The first artificial satellite was the SOVIET SPUTNLK-1 launched on October 4, 1957, and aquipped with an onboard transmitter that worked on two frequencies i.e. 20.005 and 40.002 MHz The first American satellite to relay communications was project SCORE in 1958 which used tape recorder to store and forward voice messages. Telstar was the first active, direct relay communications satellite belonging to AT T. USE OF EM WAVES IN SATELLITE COMMUNICATION The fastest growing and most recent field of communication involves the use of various satellite relays. Let us discuss the space wave communication. In this mode of propagation, electromagnetic waves from the transmitting antenna reach the receiving antenna either directly or after reflections from ground in the earths troposphere region. Troposphere is that portion of the earth which extends up to 16 km from the earth surface. It means in the former, wave reaches directly from the transmitting antenna to receiving antenna and in later, the wave reaches the receiving antenna after reflection from the ground., where the phase change of 180 degree is also introduced due to reflection at the ground, in the ground reflected wave. Although both the waves leave the transmitting antenna at the same time with the same phase but may reach the receiving antenna either in the phase or out of the phase, because the two wave travel different path lengths. The strength of the resultant waves, thu s, at the receiving point may be stronger or weaker than the direct path alone depending upon whether the two waves are adding or opposing in phase. At receiving point the signal strength is the vector addition of direct and indirect waves. Space wave propagation is also called as tropospheric propagation because space wave propagates through troposphere. Space wave propagation is mainly in VHF, and higher frequencies because at such frequencies sky wave and ground wave propagation both fail. Beyond 30 MHz sky wave fails as the wavelength becomes too shorts to be reflected from ionosphere and ground waves are propagating close to the antenna only, as attenuation is very high. Therefore just after few hundred feet ground wave also die due to attenuation and wave tilt. Space wave propagation is also called as the line of sight propagation because at VHF, UHF and microwave frequencies, this mode of propagation is limited to the line of sight distance and is also limited by the curvatur e of earth. Although in actual particle space wave propagates even slightly beyond the line of sight distance due to the refraction in the atmosphere of the earth. In line of sight distance transmitting antenna and receiving antenna can usually see each other. In fact, the line of sight distance i.e. range of communication can also be increased by increasing the heights of transmitting and receiving antennas. The curvature of earth and the height of the transmitting and receiving antennas determines maximum range of communication through direct waves. In fact, the line of sight distance has now been extended by what is known as Space Communication or specially Satellite communication which has facilitated trans-oceanic propagation of microwaves with the potentiality of large bandwidth. By space communication we mean the radio traffic between a ground station and satellite or space probe, between satellites or space probes and also between the ground station itself via man made communication satellites or natural space body( e.g. the sun, the moon, the venus etc. ). Earlier it was not possible to propagate beyond the radio horizon and hence it revolutionized the field of communication engineering and it is possible to show that three geosynchronous satellites can establish communication over entire world. Role of electromagnetic waves can be seen by studying the different bands available for satellite communication Selection of the band The selection of the band is not something that individual service providers decide, but is rather chosen by large satellite operators based on different factors. These are explained below: C-band is still the most widely available worldwide. Ku-band is becoming more available recently in regions which were less covered in the past (South America, Asia, Africa). C-band is more prone to interference from other transmission services that share the same frequencies (adjacent satellites or terrestrial transmissions) than the higher bands. While the C-band technology is cheaper in itself, it requires larger dishes (1 to 3 m) than Ku- and Ka-band (0.6 to 1.8 m) and therefore imposes relatively higher (installation) costs on the end-user. Ku- and especially Ka-band make better use of satellite capacity. Higher frequency bands (Ku- and especially Ka-) suffer significantly more from signal deterioration caused by rainfall: to ensure availability in bad weather conditions, the signal has to be much stronger. Note that 0.1% of unavailability means in fact that the service will be interrupted for almost 9 hours over a 1-year period. 1% unavailability represents 90 hours or almost 4 full days. Bands of Interest C-band is the oldest allocation and operates in the frequency range around 6 GHz for transmission (uplink) and between 3.7 and 4.2 GHz for reception (downlink). Ku-band is the most common transmission format in Europe for satellite TV and uses around 14 GHz for uplink and between 10.9 and 12.75 GHz for downlink. Ka-band uses around 30 GHz up- and between 18 and 20 GHz downlink frequency. C-band and Ku-band are becoming congested by an increasing amount of users, so satellite service operators are more and more turning to the use of Ka-band. Using C-band and K-band C Band is a name given to certain portions of the electromagnetic spectrum, as well as a range of wavelengths of light, used for communications. The IEEE C band and its variations, in particular, are microwave ranges used for certain satellite television broadcasts, and by some Wi-Fi devices, cordless phones, and weather radars. Typical antenna sizes on C-band capable systems ranges from 7.5 to 12 feet (2.5 to 3.5 meters) on consumer satellite dishes, although larger ones also can be used. Slight variations of C band frequencies are approved for use in various parts of the world. TABLE I C Band Variants Around The World Band Transmit Frequency (GHz) Receive Frequency (GHz) Extended C Band 5.850-6.425 3.625-4.200 Super Extended C Band 5.850-6.725 3.400-4.200 INSAT C Band 6.725-7.025 4.500-4.800 Palapa C Band 6.425-6.725 6.425-6.725 Russian C Band 5.975-6.475 3.650-4.150 LMI C Band 5.725-6.025 3.700-4.000 K band is defined as a frequency band between 20 and 40 GHz (7.5-15 mm). The IEEE K band is a portion of the electromagnetic spectrum in the microwave range of frequencies ranging between 18 and 27 GHz. K band between 18 and 26.5 GHz is absorbed easily by water vapour (water resonance peak at 22.24 GHz, 1.35 cm). The IEEE K band is conventionally divided into three sub-bands:  · Ka band: K-above band, 26.5-40 GHz, mainly used for radar and experimental communications.  · K-band 18-27 GHz  · Ku band: K-under band, 12-18 GHz, mainly used for satellite communications, terrestrial microwave communications, and radar, especially police traffic-speed detectors. MAIN COMPONENTS OF A SATELLITE COMMUNICATION SYSTEM Satellite communications are comprised of two basic elements The satellite The ground station The Satellite The satellite is also known as the space segment. It is composed of the following separate units; the satellite and telemetry controls and the transponder. The transponder comprised of the receiving antenna to catch-up signals from the ground station, a broad band receiver, an input multiplexer and a frequency converter that is used to reroute the received signals through a high powered amplifier for downlink. The main function of satellite is to reflect signals. In case of a telecom satellite, the primary role is to pick up signals from a ground station, which is located, a considerable away from the first. This relay action can be two way, as in the case of a long distance phone call. Another use of satellite is the television broadcasts. Number of programs are first up-linked and then down-linked over wide region. The customer having appropriate devices can receive and watch the programs. One of the modern uses of satellite is getting information along with image (commonly known as space/satellite image) of any desired location on earth. Fig. 2 diagram showing satellite and ground station The Ground Station This is called the earth segment. Earth station is the common name for every installation located on the Earths surface and intended for communication (transmission and/or reception) with one or more satellites. A base band processor, an up-converter, high Powered amplifier and a parabolic dish antenna is involved to transmit the terrestrial data to an orbiting satellite. In the case of downlink, the ultimate reverse operation is being down and up-linked signals are recaptured through parabolic antenna. WORKING OF A SATELLITE Satellite is mainly working on the basis of Electromagnetic waves. In our daily life EM waves are useful for Radio, Internet, T.V etc. For all these electronic equipments are working on the basis of EM waves. Firstly a satellite is keep in the orbit. Then it rotates along the orbit. From the source station it receives signals and spread them to all the electronic equipments. Satellites easily transfer news with in fraction of seconds it means in microseconds. In order send signals the smallest frequency waves are required. At the station the producers send the microwaves to satellite, because microwaves are waves having short frequency when compare to the other waves (Microwaves are electromagnetic waves with frequency from 30MHz to 1GB) ,they can easily penetrate throw the ionosphere, and reaches to satellite. Satellites provide links in two ways. Firstly a satellite provide point to point communication link between one ground station and the other. One ground station transmit signal to the other satellite and next ground station receives them from the satellite. Secondly, satellite receives signals from one ground station and transmits to them to the number of ground receivers. It is illustrated in figure 2. Most satellite use frequency bandwidth through from 5.92 to 6.4GHz from transmission of data from earth to the satellite and a frequency bandwidth from 3.7 to 4.1GHz for transmission from satellite to the earth. A satellite can provide service to a certain part of the earth if it is in sight. This can be done only if the satellite remains stationary with respect to the earth. LOW EARTH ORBITING COMMUNICATION SATELLITE In 1960, the simplest communications satellite ever conceived was launched. It was called Echo, because it consisted only of a large (100 feet in diameter) aluminized plastic balloon. Radio and TV signals transmitted to the satellite would be reflected back to earth and could be received by any station within view of the satellite. Fig. 3 diagram showing Echo satellite Unfortunately, in its low earth orbit, the Echo satellite circled the earth every ninety minutes. This meant that although virtually everybody on earth would eventually see it, no one person, ever saw it for more than 10 minutes or so out of every 90 minute orbit. Telstar satellite Telstar is the name of various communications satellites; including the first ever such satellite able to relay television signals. The first two Telstar satellites were Telstar 1, launched July 10, 1962 and operational until February 21, 1963, and Telstar 2, launched May 7, 1963 and operational until May 16, 1965. They were experimental, and nearly identical. Telstar 1 relayed the first television pictures, telephone calls and fax images through space and provided the first live transatlantic television feed. Telstars orbit was such that it could see Europe and the US simultaneously during one part of its orbit. During another part of its orbit it could see both Japan and the U.S. As a result, it provided real- time communications between the United States and those two areas for a few minutes out of every hour. Some of the main advantages of low and medium earth orbit include: (a) the possibility of using hand-held receiver terminals because satellites are closer to the Earth and can therefore provide stronger signals at the receiver and ground stations need to transmit at lower power; (b) the possibility of reusing the frequencies more often than is possible with geostationary orbit because the geographical area covered by low earth orbit satellites is much smaller; (c) the possibility of reduction in transmission delay. Fig. 4 diagram showing Telstar satellite Geostationary Communications Satellites In 1963, the necessary rocket booster power was available for the first time and the first geostationary satellite, Syncom 2, was launched by NASA. For those who could see it, the satellite was available 100% of the time, 24 hours a day. The satellite could view approximately 42% of the earth. For those outside of that viewing area, of course, the satellite was NEVER available. Fig. 5 diagram showing Geostationary satellite INDIAS FIRST COMMUNICATION SATELLITE APPLE Apple stands for Airline Passenger Payload Experiment. It got the name as it was carried as a Passenger by the European space agency. Apple the first Indian three-axis stabilized geo-stationary experimental communication satellite, weighing 673kg was successfully launched on June 19, 1981 from Kourou, French Guyana, by the Ariane Launch Vehicle of European Space Agency on its third developmental flight. After 17 minutes 25 seconds the craft was successfully placed in the transfer orbit. The space craft sub-systems were functioning normally. Test commands have been issued from SHAR to the APPLE space craft successfully. Fig. 6 diagram showing APPLE satellite Launch Date: 19.06.1981 Launch Vehicle: Ariane-1(V-3) Type of Satellite: Geo-Stationary Satellite Mission: Experimental geostationary communication Weight: 670 kg Communication: VHF and C-band Stabilization: Three axis stabilized (biased momentum) with Momentum Wheels, Torques Hydrazine based Reaction control system Mission life: Two years APPLICATIONS OF SATELLITE COMMUNICATION The breakthrough provided by satellites in telecommunications resulted in a major research and development effort in all the related technologies. Most of the early work concentrated on international point to point telecommunications applications. Later, the application of satellite communication was extended to the direct satellite broadcasts (1970s), mobile communications (1980s), and personal communications (1990s). In general, satellites are serving the mobile and broadcast. Radio and Television Broadcasting Satellites have been used since 1960 to transmit broadcast television signals between the network hubs of television companies and their network members. Sometime, a whole set of programs is transmitted at once and recorded at the affiliate, and then broadcast to the local populace according to the appropriate time. In the 1970s it became possible for private individuals to download the same signals that the network and cable companies were transmitting, using C-band reception dishes. This free viewing of the corporate contents by individuals let to scrambling and subsequent resale of the descrambling codes to individual customers, which started the direct-to-home industry. The direct-to-home industry has gathered even greater response since the introduction of digital direct broadcast service. . Business Radio And TV Digital television has made it possible to distribute information within organizations and companies that are geographically dispersed, or to deliver distance education. Similarly, digital radio allows for the delivery of radio services to relatively small closed user groups. Thin Route or Trunk Telephony Telecom operators have been using satellite communications for many years to carry long-distance telephone communications, especially intercontinental, to complement or to bypass submarine cables. To the end-user this is transparent: the phone calls are routed automatically via the available capacity at any given moment. Mobile satellite telephony Mobile telephony allows the user to make telephone calls and to transmit and receive data from wherever he/she is located. Digital cellular mobile telephony such as GSM has become a worldwide standard for mobile communications, but its services lack coverage over areas that are sparsely populated or uninhabited (mountains, jungle, sea), because it is not economically viable or practical for the network operators to build antennas there. Satellite telephony seems to be able to provide a possible solution to the problem of providing voice and data communications services to these other locations Marine Communications In the marine community, satellite communication systems such as Immarsat provide good communication links to ships at sea. These links use a VSAT type device to connect to geosynchronous satellites, which in turn links the ship to a land based point having respective telecommunications system. Global Positioning Services Another VSAT oriented service, in which a small apparatus containing the ability to determine navigational coordinates by calculating a triangulating or the signals from multiple geosynchronous. Military Satellite System For military communications Army, Air force and Navy use both fixed and mobile satellite systems. In addition to the normal communications, military communications are also required for tactical communications from remote and inhospitable locations. The special requirements of military communication terminals are high reliability, ruggedness, compact, operations under hostile environment, immunity to jamming, ease of portability and transportation, etc. Examples of military satellite communications systems are: DSCS (US AF) SKYNET (UK) NATO (NATO) FLTSATCOM (US NAVY) MILSTAR Because of the special frequency band used in Military satellite system and other special requirements, Military satellite Systems are always much costlier and it takes longer time to design and develop compared to commercial satellite communications systems. Realizing that not all communications are strategic in nature, there is a trend now to use commercial communications system as far as possible. US Department of Defence is one of the major users of commercial Iridium satellite system with their own gateway. Broadband Satellite System Broadband satellite service is an emerging service which has caught the fancy of many for meeting the demand of worldwide fibre like access to telecommunications services such as computer networking, broadband Internet access, interactive multimedia and high quality voice. These systems use advanced satellite technology at Ka band or Ku band frequencies to achieve the high bandwidth requirements. Examples of proposed Broadband Satellite systems are: Teledesic, SkyBridge, Spaceway LIMITATIONS OF SATELLITE COMMUNICATION Latency (Propagation Delay) Due to the high altitudes of satellite orbits, the time required for a transmission to navigate a satellite link (2/10ths of a second from earth station to earth station) could cause a variety of problems on a high speed terrestrial network that is waiting for the packets. Poor Bandwidth Due to radio spectrum limitations, there is a fixed amount of bandwidth allocable to satellite transmission. Noise The strength of a radio signals strength is in proportion to the square of the distance travelled. Due to the distance between ground station and satellite, the signal ultimately gets very weak. This problem can be solved by modulation of carrier wave. Conclusion The outer space has always fascinated people on the earth and communication through space evolved as an offshoot of ideas for space travel. The earliest idea of using artificial satellites for communications is found in a science fiction Brick Moon by Edward Evert Hale, published in 1869-70. While the early fictional accounts of satellite and space communications bear little resemblance to the technology as it exists today, they are of significance since they represent the origins of the idea from which the technology eventually evolved. The satellite communication through the EM waves has many applications for the smooth functioning of life and it made the communication with each other very simple. In the area of satellite communications, the technology has been responsive to the imaginative dreams. Hence it is also expected that technological innovations will lead the evolution of satellite communications towards the visions of today. Acknowledgment I would like to express my gratitude to all those who gave me the possibility to complete this term paper. I want to thank department of Electronics and communication of lovely professional university for giving me permission to commence this term paper. I have further more to thank the EMFT faculty member, Mr. Princejeet Singh. I am bound to the physics faculty for their stimulating support. My friends Amit and Sulabh supported me in this term paper. I want to thank them for their help, support, interest and valuable hints. Especially I would like to thank my sister who helped me and enabled me to complete this term paper.

Nomos vs. Physis in Sophocles’Antigone and the Modern World Essay

Nomos vs. Physis in Sophocles’Antigone and the Modern World The Greek play, Antigone, written by Sophocles in the year 441 BCE, honors the Greek god of wine, Dionysus. It is hard to imagine that a play, written century ago for an imaginary god, would still be widely popular and have great significance in today's world. Using two main characters, Antigone and Creon, Sophocles creates a dialogue that examines two very different views of nomos (law) and physis (nature), the focal point of all Greek beliefs. These two terms were often the key in deciding what was considered right and wrong among the Greeks, and people still use nomos and physis in today's society centuries later. Throughout Antigone, Creon and Antigone use nomos and physis to defend their actions taken when Antigone breaks a law made by Creon, because she feels it impedes upon the unwritten laws of the gods, much like anti gay advocates defend their stance on protecting the sanctity of marriage, while gay activists oppose it because it violates their fundamental constitutional ri ghts. Using Creon and Antigone, Sophocles illustrates the way that nomos and physis support their opposing viewpoints. When Antigone's two brothers, Eteocles and Polyneices, kill each other in battle, Creon, her uncle, succeeds to the throne. Once in power, he makes a law that no one can bury Polyneices because he was un-loyal to his native land. If anyone defied his new law by burying him, then the perpetrator would be killed and left unburied. However, Antigone felt that both of her brothers should have a proper burial, and disobeyed Creon's law by burying Polynneices knowing she would have to suffer the consequences. When brought before Creon, she defended her actions through phys... ... constitution. They believe that the law should not decide who people can love, and that it is a persons right to marry whomever they want. Therefore, the terms nomos and physis are still used in today's society in similar ways to that of Creon and Antigone centuries ago. Even though Antigone was written centuries ago, the basic principles of nomos and physis can still be applied in today's world. The way that the two terms are interpreted will vary from person to person, and there is no right or wrong answer. As long as there are controversial issues in the world, peoples opinions of nomos and physis will continue to evolve and change through time. Works Cited Sophocles. Antigone. Exploring Literature: Writing and thinking About Fiction, Poetry, Drama, and the Essay. Ed. Joseph Terry. New York: Addison-Wesley Educational Publishers Inc, 2001. 123-154.

Self-Acceptance is the Key to Happiness :: Happiness Essays

Is life really about the 'money', the 'cash', who has the biggest gold chain or who drives the shiniest or fastest car, who sells the most albums or who has the most respect? Today happiness is viewed in many different ways. Everyone defines happiness according to their personal perpectives. Each individual describes their inner feelings in a way that you can't compare with another. Happiness originally and logically means the inner state of well being or a pleasurable or satisfying experience. It enables you to profit from your highest: thoughts, wisdom, intelligence, common sense, emotions, health, and spiritual values in your life. What makes you happy and what makes me happy are different things. Whatever it is that gives you warm fuzzes is determined by you, and only you. This difference is what makes the world interesting. Most of the happiness that we experience comes from the feeling of love. So many people look to their love relationships,especially marriage to give them the happiness that they cannot find on their own. Love is not enough to provide happiness, then there must be many frustrated lovers in the world. The belief that love gurantess happiness is left over from the ideology of romantic love that tells us we will live happily ever after if we can only find the right person with whom to spend our life with. If we realize that love by itself will not bring happiness, then hopefully we will be more tolerant of the imperfections of those we love. If our relatioships have their problems and if those we love do not always meet our expectations it doesn't mean that we have lost our chance for happiness. When we do not expect love to give us the happiness we seen, there will be more room for forgiveness of the imperfections and problems that always accompany love. What makes us happy is so varied. To be happy is a fleeting thing, which we enjoy so much and often want it back as soon as possible .The things that make me happy in my life can seem boring to others.My happiness is my health,my success and my marriage. My happiness is to have a shoulder to lean on when my days are going bad. Marriage has helped me look forward for my future. It opened my heart and my mind to the true existing world. It's not like I wasn't happy before I got married.

John Updikes A&P :: essays research papers

Bathing Beauties   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   John Updike’s â€Å"A&P† is a short story about a nineteen year old boy during the 1960’s that has a summer job at the local A&P grocery. The main character in the story, Sammy, realizes that life isn’t always fair and that sometimes a person makes decisions that he will regret. Sammy sees that life doesn’t always go as planned when three young girls in bathing suits walk in and his manager Lengel gives them a hard time, and he comes to term with that sometimes you make bad decisions. Sammy is astounded by three young girls that walk into his store in their bathing suits. He follows their every move as they peruse over the cookies and other goods. The first thing this typical nineteen boy recognizes is the one girl’s â€Å"can†. But then he goes on to say that this girl is one that other girls seems to think has potential but never really makes it with the guys. One girl though especially catches his eye. He starts to call her â€Å"Queenie† because of the way she carries herself and that she seems to be the leader of the pack. Sammy does nothing but watch her every move as they parade about the store. He even daydreams about going into her house with her rich family at a cocktail party. He notices everything about her and thinks there was nothing cuter than the way she pulls the money out of her top. His immature infatuation with this girl is one of the reasons Sammy makes the hasty decision to quit in the end. Lengel, the manager of the store, spots the girls and gives them a hard time about their dress in the store. He tells them, â€Å"Girls, this isn’t the beach.† He says that they are not dressed appropriately to come into this grocery store. Lengel’s words cause Queenie to get embarrassed and start to blush. Sammy cannot believe this and gets frustrated at his boss. He doesn’t believe that it is right to prosecute these innocent girls for the way they are dressed. He also states at this point that the sheep are piling up over in Stokesie line trying to avoid all the commotion the scene has caused. I believe Sammy takes this as the last straw in a long string of aggravations. Sammy confronts Lengel and tells him that he didn’t have to embarrass them like that, but it does no good.

Brazil and India business environment comparison Essay

The United States and Brazil entered into a common agreement targeting to improve democracy in the Western Hemisphere and to bring an accelerated growth in regional trade and development so that the governments of the region can ensure its citizens better scope for greater prosperity. (Common Goals and Challenges in Brazil-US’s Agenda) The prospects for conducting business in Brazil are tremendous in view of its 150 million possible consumers, a hugely diversified economy and a gross domestic product worth of US$447 billion. However, till the nation attains improved market and economic reforms, majority of the opportunities for US companies are prone to hover around particular sectors and projects. (Jennings, 14) The closed markets and heavy government interventions marked the economic development of Brazil during the last thirty years. During the 1960s and 1970s, such policies of import substitution and huge levels of international debt generated accelerated growth and industrialization however, giving rise to long term problems like long term economic difficulties, inclusive of high inflation, foreign debt difficulties and non-competitive industries. During the year 1990 the Government of Brazil initiated remarkable market liberalization measures including reduction of trade and investment barriers, declining import duties over 100% to a high of 35% inclusive of an average of 14%. Market liberalization also incorporated several tax and regulatory variations that have been of advantage to the foreign investors. The reduction of taxes on profit remittances and simplification of procedures and withdrawal of some of the disincentives to reinvest the profits have provided increasing scope for business activities in Brazil. As a result, the trend of the reaction of US companies was seen to be remarkable. (Jennings, 14) US companies exported goods of worth $6 billion enabling Brazil to be among the top 20 export markets of the world. The United States tends to maintain the position of being the single country supplier to Brazil constituting about one-third of the total of the Brazilian imports. The telecommunication and informatics market of Brazil extends fabulous prospective for US business, for the equipment manufacturers as well as for the service providers. The Telecommunication sector provides a market worth of $3 billion in Brazil. The US companies have presently extended limited involvement in the telecommunication sector and are exploiting the benefits of extending private networks as well as equipments. The energy sector in Brazil also entails good prospects for US technology as well as equipment. The current agreements and subsequent legislations at higher government levels and the private sectors assures for future prospects. The US equipment manufacturers are encouraged to actually take benefit of the opportunities that already prevail and are prone to expand with regard to the internal demand that promotes the expansion of this sector. (Jennings, 15) The Indian markets along with its over one billion population, provides profitable as well as diverse opportunities for US exporters with the right kind of products, services as well as commitment. Such opportunities are accelerated with the depreciation of dollar in the recent years in relation to its competitive currencies. The infrastructure, high-tech, energy, health care, environmental, transportation as well as defense sector are prone to surpass the tens of billions of dollars mark in the mid-term as the Indian economy tend to globalize as well as emerge stronger. In the year 2005, the total bilateral trade was $26. 77 billion. The US exports to India in 2005 was enhanced to $7. 96 billion, which was a 30. 3 percent growth in comparison to the previous year. (India – Market of the month) The potentiality of India for US companies is promising since India is the second largest small car market of the world; India is one among the three countries that manufactures its own supercomputers; India is the one among the six nations that is able to launch its own satellites and; India is having the second biggest group of software developers immediately after the US. The Indo-US relation is presently growing through a remarkable transition. The two nations which were having a gap between them in political and economic terms during the latter part of the 20th century, presently consider their national goals converging on several areas. (India – Market of the month) Indian tariffs have been decreased considerably since the early part of the 1990s. Irrespective of the fact that the tariff and poor infrastructure entails remarkable challenges for foreign investment and development, the infrastructure needs in India also entail trade and investment facilities for US companies. The best prospects for US firms and US exports on the basis of estimated Indian imports from the US has been earmarked to be â€Å"Airport & Ground Handling, Computer and Peripherals, Education Services, Electrical Power Generation, Transmission & Distribution Equipment, Food Processing & Cold Storage Equipment, Oil & Gas Field Machinery, Pollution Control Equipment, Safety and security equipment, Telecommunication equipment, Textile Machinery, water etc†. (India – Market of the month) Condoleezza Rice, Secretary of State for United States and Celso Amorim, Brazilian Foreign Minister in their meeting on 26th April, 2005 in Brazil had a discussion in relation to the common agenda of the two nations as well as that of the unique challenges which were confronting the entire hemisphere. (Common Goals and Challenges in Brazil-US’s Agenda) Brazil as well as Argentina poses certain particular business challenges to be confronted by the US firms. For example, legal provisions with regard to importing technology materials require payment of duties, tariffs and a value added tax — VAT which is as much as 22 percent of the total cost in Brazil. The business is even more complex in Brazil due to the variation of importation laws from one province to another. The fluctuating currency exchange rates as well as local economic issues pose grave challenges for conducting business. (Business Spotlight: Arrow South America) Franklin L. Lavin, Under Secretary of Commerce for International Trade, American Chamber of Commerce, New Delhi on May 1st, 2006 remarked that the Indo-US relationship have improved on many fields and have great prospects in the sphere of trade. However, US face remarkable challenges as well. Irrespective of the fact that India has exhibited good trade statistics and the progress in the sphere of economic reforms and are opening markets during the last one and half decade there still need to be improvement in several spheres in order to reflect India’s important part in the world economy. The economic philosophies of Fabian socialism as well as third world nationalism are holding India hostage for many years. As a result of this it has been pointed out that even with 30 percent growth in US exports to India during the last year, India could constitute only 1 percent of all exports of US. The economic reforms in India is in relation to world reforms as a result of this the momentum of India is not impressive in the context of the competition for global attention. (Remarks by Franklin L. Lavin Under Secretary of Commerce for International Trade, American Chamber of Commerce, New Delhi) The annual US exports of $8 billion dollar is what the US ships to Canada within two weeks. In terms of the US foreign direct investment in India the cumulative figure is only $6. 2 billion at the end of 2004, US being the largest investor while the US FDI in Singapore remains amounts to be $56. 9 billion. Irrespective of the fact that tariff for non-agricultural products have significantly reduced, it still remains at 40% in case of agricultural products. The vibrant IPR regime is considered critical to the enhancement of a creative, technologically advanced economy. Irrespective of the fact that India has opened up a silver of its retail sector to foreign investment, presently, the sector is still considered to be closed to most of the American retailers. US companies required to obviate the aggressive competition exerted by the companies from Europe, Canada, Korea and Japan by knowing how to adapt their products as well as facilitate their activities in order to take advantage of the huge potential in India. (Remarks by Franklin L. Lavin Under Secretary of Commerce for International Trade, American Chamber of Commerce, New Delhi) The trading companies are generally prone to four types of risk such as strategic risk, operational risks, internal financial risks and compliance risks. (Sadgrove, 83) The trading risks in Brazil are considered substantially greater in comparison to the developed nations. The political risks like dismissal or appointment of a key government minister can exert influence on the value of the share of the company to have fluctuations. The purchase of shares of Brazilian companies is subject to increasing risks of fluctuations in the exchange rates that may exert considerable losses. Exchange rates also have a tremendous impact on the profitability. Inflationary trends also influence much on the profitability by making the services of the company more expensive. (Sands, 27) For US Government, for over several years Brazil has been a bastion of anti communism while the other states of South America seem to be leaning towards communistic. Moreover, the US companies in Brazil never desire to take the risk by means of their operations being disrupted by that of the shipping turmoil. (Fitzgerald, 20) The US companies engaged in outsourcing of their software development to India are prone to be hurt by the industrial espionage and poor intellectual property safeguards. However, India is seen to have a far outstanding cultural and legal climate for IP protection than many other nations offering offshore coding. (Pedraja; Toman, 164) References Business Spotlight: Arrow South America. Retrieved from http://www. arrow. com/media_center/news/BusinessSpotlightArrowSouthAmerica. htm Accessed 11 December, 2006 Common Goals and Challenges in Brazil-US’s Agenda. 27 April, 2005. Retrieved from http://www. brazzilmag. com/content/view/2207/ Accessed 10 December, 2006 Fitzgerald, Michael. Intellectual property protection. CIO Magazine. 15 November, 2003. pp: 18-21 India – Market of the month. US Commercial Service India. Retrieved from http://www. buyusa. gov/india/en/motm. html? print=1 Accessed 10 December, 2006 Jennings, Horace. Brazil: slowly emerging giant offers enormous potential. Business America. March, 1994. Vol: 115; No: 3; pp: 14-16. Pedraja, Rene de La; Toman, Rene De La Pedraja. Latin American Merchant Shipping in the Age of Global Competition. Greenwood Press. 1999. Remarks by Franklin L. Lavin Under Secretary of Commerce for International Trade, American Chamber of Commerce, New Delhi. 1 May, 2006. Retrieved from http://www. ita. doc. gov/press/speeches/lavin_050106. asp Accessed 11 December, 2006 Sadgrove, Kit. The Complete Guide to Business Risk Management. Gower Publishing, Ltd. 2005. Sands, Gary. The Risks and Rewards of Investing in Brazil. Brazzil Magazine. 23 March, 2005. pp: 27-30