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Traditional planning is difficult to collect data from geographic entities. Therefore, planning models often neglect the influence of surface factors (obstacles), and often do not have practicability and operability, resulting in low longitude results. In addition, traditional planning is difficult to achieve visualization and intuition. Therefore, the introduction of Google Earth software in power grid planning is necessary, which aimed at applying geomorphological factors to planning. This paper expounds the principle of power network planning based on GE satellite map. The application adopts C/S mode to store the information and map of power network equipment on the server. After the client connects the server online, the tile map can be downloaded from Google Earth. Then, Tile Technology of GMap is used to integrate the downloaded map into a complete map and the longitude and latitude coordinates of each grid equipment are obtained from the GIS database of the full service data center. After that, the grid equipment graphics are finished by GDI+ technology. Finally, with the chosen planning project, the system can dynamically work out the plan, including the location, graphics, scale, wiring situation, estimation of investment, etc. Results show that Google Earth can improve the efficiency of power grid planning.

Mechanical engraving surface texturing methods are proposed, and pin-on-disc configuration tribological tests are carried out to investigate the effect of microgrooves, with different microgrooved direction and area ratio, on tribological performance of rock bit sliding bearing (RBSB). The RBSB, always working under low-speed and heavy-load conditions, is made of 20CrNiMo /beryllium bronze. Compared with untextured samples, wavy microgrooved tribopairs with area ratio of 5% and reference angle of 15° exhibit lower friction coefficient and wear rate. Experimental results show a reduction of 54% in friction and 78.8% reduction for wear rate, revealing that microgrooves show great potential in improving the service life of RBSB.

The influences of frictional characteristics of textured surface on rock bit sliding bearing have been investigated through unit experiments where the friction couple was equivalent to a pin-on-disc configuration. Cylindrical and elliptical textures are designed with different sizes, densities ratio and depths, fabricated using precision micro-mechanical engraving. Under the identical testing conditions in which the test force is 430 N and average linear velocity is 0.29 m/s, cylindrical texture with diameter of 300 µm, density ratio of 5.04%, and depth of 40 µm, exhibits lower friction coefficient, temperature rise and wear loss than that of untextured unit specimens. Friction coefficient decreased by 56.3%, similarly temperature rise decreased by 51.9%, and wear loss of textured disc specimens decreased by 52.9%. This study presents that the designed texture with relative small size and density ratio has obvious effect of lubrication and antifriction improvement compared with other specimens which has the same texture depth of 40 µm that it is approximately half of rock bearing radial clearance for rock bit sliding bearing under low-speed and high-load operating conditions.