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China to help Europe Develop GPS Rival
China is to contribute to a new global satellite navigation system being developed by European nations. The Galileo satellite system (51) a more accurate civilian alternative to the Global Positioning System(GPS), operated by the US military. China will provided 230m Euros (USD 259m) in (52) and will cooperate with technical, manufacturing and market development. "China will help Galileo to (53) the major world infrastructure for the growing market for location services, " said Loyola de Palacio, EU transport commissioner.
A new center that will coordinate co-operation was also announced (54) ) the European Commission, the European Space Agency (ESA) and the Chinese Ministry of Science and Technology not long (55) . The China-Europe Global Navigation Satellite System Technical Training and Cooperation Center will be (56) at Beijing University. China has a substantial satellite launch industry and could potentially help the Galileo satellites.
The US has claimed that Galileo could interfere (57) the US ability to downgrade the GPS service during military conflicts. European officials say this is unfounded and counter that US opposition (58) the commercial challenge Galileo would present to GPS. Galileo will be precise to within a meter, while civilian GPS service is accurate to around 10 meters.
The Galileo satellite constellation will (59) 27 operational and three reserve satellites orbiting the Earth at an altitude of 23,600 km. The satellites will be strung along three medium-Earth orbits at 56 degrees inclination to the equator and will provide global coverage. The system should be operational by 2008 and the entire project is expected to (60) around 3.2 billion Euros(USD 3.6 billion).
The European Commission has said Galileo will primarily be used for transportation technology, scientific research, land management and disaster monitoring.
Galileo will provide two signals: a standard civilian one and an encrypted, wide-band signal (61) the Public Regulated Service (PRS). This second signal is designed to withstand localized jamming and will be used by police and military services in Europe. European Commission (62) have said China will not be given access to the PRS.
The first Galileo satellite is scheduled to launch late in 2004, Clocks on board the (63) Will be synchronized through 20 ground sensors stations, two command centers and 15 uplink stations.
Receivers on the ground will use time signals from the satellites to precisely calculate their (64) . A "search and rescue" function will also (65) distress signals be relayed through the constellation of satellites.
(51)
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Very few go out into the world knowing exactly what they want and realizing their own abilities. The reason behind all this confusion is that there never has been a proper vocational guidance in our educational institution. Nearly all grope (摸索) in the dark and their chief concern when they look for a job is to ask what salary is like. They never bother to think whether they are suited for the job or, even more important, whether the job suits them. Having a job is more than merely providing yourself and your dependants with daily bread and some money for leisure and entertainment. It sets a pattern of life and, in many ways, determines social status in life, selection of friends, leisure and interest.
In choosing a career you should first consider the type of work which will suit your interest. Nothing is more pathetic than taking on a job in which you hive no interest, for it will not only discourage your desire to succeed in life but also ruin your talents and ultimately make you an emotional wreck (受到严重伤害的人) and a bitter person.
The reason why some people are unlikely to succeed in life is that they ______.
Which of the following statements is true？
Why do researchers develop a new device to monitor signs of landsides？
Egypt Felled by Famine
Even ancient Egypts mighty pyramid builders were powerless in the face of the famine that helped bring down their civilian around 2180 BC. Now evidence gleaned(搜集) from mud deposited by the River Nile suggests that a shift in climate thousands of kilometers to the south was ultimately to blem -- and the same or worse could happen today.
The ancient Egyptians depended on the Niles annual floods to irrigate their crops. But any change in climate that pushed the African monsoons(季风)southwards out of Ethiopia would have diminished these floods.
Dwindling(逐渐变少；使变少)rains in the Ethiopian highlands would have meant fewer plants to establish the soil. When rain did fall it would have washed large amounts of soil into the Blue Nile and into Egypt, along with sediment(沉积；沉积物)from the White Nile.
The Blue Nile mud has a different isotope signature(签名；特征) from that of the White Nile. So by analyzing isotope(同位素；核素)differences in mud deposited in the Nile Delta, Michael Krom of Leeds University worked out what proportion of sediment came from each branch of the river.
Krom reasons that during periods of drought, the amount of the Blue Nile mud in the river would be relatively high. He found that one of these periods, from 4,500 to 4,200 years ago, immediately predates the fall of the Egypts Old Kingdom.
The weakened waters would have been catastrophic for the Egyptians. Changes that affect food supply dont have to be very large to have a ripple effect in societies, says Bill Ryan of the Lamont Doherty Earth Observatory(天文台)in New York.
"Similar events today could be even more devastating, " says team member Daniel Stanley, a geoarchaeologist(地质考古学家) from the Smithsonian Institution in Washington, D. C. "Anything humans do to shift the climate belts would have an even worse effect along the Nile system because the populations have increased dramatically. "
Why does the author mention "pyramid builders"？
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