|
Designed by Shandong High Speed Croup, from the was were only available in December 2006 and finished in December 2010, after 14 years of planning researches since 1993, which employed 30,000 workers to develop, and used 450,000 tons of steel and a couple of.3 million cubic meters of concrete, using a total investment of approximately 9 billion yuan. The open from the bridge will decrease traffic time from Qingdao to Huangdao District by at least twenty minutes and release pressure about the Jiaozhou Bay Expressway. Furthermore, the Qingdao Haiwan Bridge will be the starting area of national expressway from Qingdao to Lanzhou and also the key part of high way net of Shandong.
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
New Car Buying Tips--



Copyright ?1998-2017 Technews Corp, All rights reserved
|
