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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
Glasses, also known as eyeglasses or spectacles, are devices consisting of glass or hard plastic lenses mounted in a frame that holds them in front of a person's eyes, typically using a bridge over the nose and arms which rest over the ears. Glasses are typically used for vision correction, such as with reading glasses and glasses used for nearsightedness. Safety glasses provide eye protection against flying debris for construction workers or lab technicians; these glasses may have protection for the sides of the eyes as well as in the lenses. Some types of safety glasses are used to protect against visible and near-visible light or radiation. Glasses are worn for eye protection in some sports, such as squash. Glasses wearers may use a strap to prevent the glasses from falling off during movement or sports. Wearers of glasses that are used only part of the time may have the glasses attached to a cord that goes around their neck, to prevent the loss of the glasses.
In addition to the basic detection and alarm functions, the current metal detectors provide special functions specially developed by various manufacturers, such as:
It?s a truth, buildings move. Tiny shifts in underground stability or building settlement may cause cracks within your shower or bathroom. There are other causes, but a crack inside wall and floor junctions or even in between grouting and tiling causes massive problems to the wall and floor behind them. By using the DiaOSeal system developed by Shower Repairs Plus, they are able to repair, re-seal and still provide a water-tight shower or bathroom with a very long lasting finish. The DiaOSeal Hydro-barrier can be a clear liquid that seals the tiled area, stops further leaks which is totally non-invasive.
Of course, repairing a damaged alloy wheel might be tricky. Many think that a cracked or bent wheel can simply be bent back into place, nonetheless it isn't that simple. Fortunately, we of experts carries a method of safely repairing a damaged wheel that may remove even unnoticeable cracks and other weak spots. The wheel is installed on a vehicle simulator, and as heat, pressure and lightweight vibrations are applied to the wheel the alloy moves back in place without cracking. The wheel retains its original strength once it cools. It is also washed thoroughly, since brake dust and rust can hide small cracks. Once the wheel is restored and cleaned, it can be inspected thoroughly by all of us of experts.
New Car Buying Tips--


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