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Spacecraft flew hundreds of thousands to hundreds of millions of kilometers from the earth, injecting speed when the size and direction of a slight error, arrived at target planets will appear large deviation error, for example, when Mars probe injecting speed 1 m/s speed (about one over ten thousand), arrived at Mars, about 100000 km distance deviation. Therefore, precise control and navigation must be carried out during the long flight. Flying to the moon is usually controlled by the orbital control system of the ground and space probe (see orbit control). Interplanetary flight distances, radio signal transmission time is long, the real-time remote control, can't so planets and interplanetary spacecraft orbit control system shall have the ability of autonomous navigation (see interstellar travel navigation and control). The United States, for example, "pirates" spacecraft in space flight of more than eight hundred million km, for 11 months of 2000 times of autonomous orbit adjustment, the final surface to achieve a soft landing on Mars, placement accuracy up to 50 km. In addition, in order to ensure the accuracy of the orbit control engine, the communication antenna is always aimed at the earth, and other systems work normally, and the detector has the autonomous attitude control ability
Teamwork inspires the incredible potential of team members and enables everyone to exert their greatest strength. However, one plus one results are more than two, which means that team work can often exceed the sum of individual performance.
It?s been a long time since people in Japan?s Nissan boiler rooms attended with a design value luxury and sports bravado. But our car lease specials radar have picked up on what appears to be the new Nissan GT-R which has been first put into the idea car category almost ten years ago. So can it finally be released?
Designed by Shandong High Speed Croup, the construction was entered December 2006 and finished in December 2010, after 14 a lot of planning researches since 1993, which employed 30,000 workers to develop, and used 450,000 plenty of steel and 2.3 million cubic meters of concrete, having a total investment of approximately 9 billion yuan. The open of the bridge will decrease traffic time from Qingdao to Huangdao District by at the very least 20 minutes and release pressure for the Jiaozhou Bay Expressway. Furthermore, the Qingdao Haiwan Bridge is the starting section of national expressway from Qingdao to Lanzhou and the key part of high way net of Shandong.
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