Global Positioning System Essays (1057 words) -

Global Positioning System The Global Positioning System. What is GPS? The global positioning system is a satellite-based navigation system, developed and operated by the U.S. Department of Defence, consisting of a network of 24 orbiting satellites that are eleven thousand nautical miles in space, at an inclination of 55 degrees and in six different orbital paths. The satellites are constantly moving, making two complete orbits around the Earth in just less than 24 hours. The GPS satellites are referred to as NAVSTAR satellites. GPS uses these 'man-made' stars as reference points to calculate positions accurate to a matter of metres. Advanced forms of GPS can make measurements to better than a centimetre. GPS now permits land, sea and airborne users to determine their three dimensional position anywhere in the world very precisely and accurately. The user segment consists of receivers, processors and antennas. The vast majority of applications of precision possible with GPS is primarily of scientific and military use, but it is worth noting that these days, GPS is finding its way into cars, boats, planes, construction equipment and a lot more. Principles of Operation of GPS The GPS satellites orbit the Earth twice a day, 11,000 miles above the Earth transmitting their precise position and elevation. In brief, the GPS receiver acquires the signal, then measures the interval between transmission and receipt of the signal to determine the distance between the receiver and the satellite. Once the receiver has calculated this data for at least three satellites, its location on the Earth's surface can be determined. This is the basis of triangulation, which works as follows: -Determining the exact distance to one satellite narrows down the receiver's position to some place on an imaginary sphere. -Knowing the exact distance to a second satellite narrows the position down to the intersection of two spheres or a circle of points. -Knowing the exact position of a third satellite narrows the possibilities down to two points of intersection. The exact position is usually known now because one of the points is usually not on the surface of the Earth. A fourth satellite position can be used to find the one single location without any doubt. (This will be discussed later). This is how position is calculated, but how is the distance measured from the receiver to the satellite? Basically, it is measured by timing how long it takes for a signal sent from the satellite to arrive at the receiver. Both the satellite and the receiver simultaneously generate the same pseudo random code. The time delay before both codes will synchronise, multiplied by the speed of light gives the distance. Diagrammatically, It should be explained that the pseudo random code is just a very complicated code that looks like random electrical noise. The reasons for the complexity are: -It helps make sure that the receiver doesn't accidentally sync up to some other signal. -It guarantees that the receiver doesn't accidentally pick up another satellite's signal as each satellite has its own unique pseudo random code. -The code makes it possible to use 'information theory' to 'amplify' the GPS signal. As well as the GPS signal containing a pseudo random code, every satellite also transmits almanac and ephemeris data. The almanac data is general information on the location and the health of each satellite in the constellation, which can be received from any satellite. Ephemeris data is the precise satellite positioning information that is used by the GPS receiver to compute its position. Each satellite transmits its own ephemeris data. It is of utmost importance that timing is extremely precise. Satellites have atomic clocks that can make precise time measurements, while available GPS receivers don't. To correct this, a fourth satellite distance measurement is made, providing perfect timing or atomic accuracy clock measurements. One consequence of this principle is that any decent GPS receiver will need to have at least four channels so that it can make the four measurements simultaneously. Exact distance has now been obtained and the exact position of the satellite is known due to ephemeris data. Therefore, perfect position calculations could be made. It is worth mentioning that the Department of Defence constantly monitors the GPS satellites. There is a master control station in Colorado Springs and five monitor stations and three ground antennas located throughout the world. The

Samesex Marriage essays

Samesex Marriage essays There are many important issues discussed in public policy today. One of these issues is homosexual marriage. This is an important issue because it deals with a relatively large minority of the United States. This issue is put into many different lights. Those of morals, family values and religion; and those of equality, constitutionality, and right to privacy. The aspect with the most relevance is constantly left up to debate. Homosexuals are 'gay' due to a combination of factors. These factors are environment and society-the outside influences- and genetics. Hence, homosexuals do not decide their own sexuality, nor do heterosexuals. Therefore, homosexuals should have the same rights as heterosexuals, one of these rights being marriage. If it is proven that there is indeed a gene that causes homosexuality, than we can draw a parallel between not allowing homosexuals to marry and not allowing blonds to marry. This is why it is of great importance to public policy whether or not homosexuality is predetermined. Some now believe that homosexuality is genetically predetermined by a gene on the X chromosome. If this is the case, then gays cannot decide their sexual orientation, for it is predetermined. Hence, not allowing those who are genetically inclined to prefer the same sex to marry leaves homosexuals with three choices. The first is to remain celibate their entire lives so as not to "live in sin"; the second is to marry someone they do not truly love or find attractive simply for the marriage benefits; the third and final choice is to live together with their partner and face the dirty looks of fellow citizens, simply because they are living together though they are not married. Marriage goes beyond the benefits, however. The institution of marriage is a very respected one, and holds much sentimental value for many people. If we look at the Declaration of Independence for inspiration, we read that all men...

Should Homosexual Couples be Allowed to Adopt Research Paper

Should Homosexual Couples be Allowed to Adopt - Research Paper Example So, therefore if the same sex couples are in a  monogamous relationship, financially stable and most importantly a loving relationship, they  should be allowed to adopt a child if they decide to do so. Homosexual couples are capable of  raising healthy children, their life style will not be transcended to them and they will not be  psychologically damage as suggested by the traditional family. Being a heterosexual  does not guarantee you being a better parent. This paper will explore why homosexual couples  are fit parents and children that are abandoned can be given a chance at better life with these  parents.  Homosexual couples who are given the right to adopt children can have the same  advantages. The anticipation for health alteration and development as children is same whose parentages  are heterosexual. This is absolutely ridiculously and nonsensical. Our society imposes prejudices and biases  against people who are different and not considered â€Å"no rmal.†Ã‚  The legal procedures and structures throughout the world leave the same sex couples desiring to be parents with two options. Firstly, the couples can always adopt the children of their partners. This is termed as second adoption option which is somewhat an extension of what we call as adoption by step parents. Another has been the traditional options allowing homosexual couples to become foster parents. Already mentioned this law has enforced by the government of Florida. Under this law homosexual couples are devoid of the rights to become legal parents. There is no basis on which to assume that a parental homosexual orientation will  increase the likelihood of or induce homosexual tendencies in the child. The most important  role of any parent, same-sex or heterosexual, is to provide the basic needs, such as food, shelter,  clothing, health-care and love (Patterson, 1025-30).  Public controversies do not stop chasing case of same sex adoption even though the re are enough evidences to suggest that homosexual couples strive to fulfill all the necessities of their children. Homosexual couples are capable of raising healthy children, their life style will not be transcended to them and they will not be  psychologically damaging as suggested by the â€Å"so call traditional family†. Our findings have proved that gay couples are more interested in adoption compared to the heterosexual couples. This point is proven with the help of the statistics from The National Survey of Family Growth which shows that 46.2% homosexual couples are interested in adoption compared to 32.3% in heterosexual couples. 5.7% homosexual couples are even ready to take concrete steps for adoption compared to 3.3% heterosexual couples (Brodzindsky and Pertman, 64). Such a data shows that future of many more children could be secured if eligible homosexual couples are allowed to adopt. In most of the cases it has also been found that such same sex couples are b etter educated and more financially stable. But out of such 3.1 million couples only 1.6 million have been given the right for adoption (Brodzindsky and Pertman, 64). This shows pure discrimination on basis of abnormal sex orientation. When heterosexual couples can still have children with medical assistance, homosexual parents will naturally have more urge towards adoption and this will ascertain security for many orphans. With proper monitoring of their activities for at least a couple of years after the adoption the safety of the