Applied Mechanics and Materials Vols. 295-298

Abstract: In order to meet the designed demands of military seabed sediment thematic map, this paper researches the designed methods of sediment symbols on military seabed sediment thematic map. Combined with analyzing the characteristics of sediment elements, this paper studies the restrictive factors and designed principles of seabed sediment symbols on general charts. For the sake of the requirements of marine military affairs, this paper discusses the designed principles and implemented methods of sediment symbols on military seabed sediment thematic map.

Abstract: Spatial data is becoming increasingly important in forestry resource management and decision making. However, huge amount of accumulated spatial data were not fully utilized due to the difficulty of sharing and integration. A forest spatial data sharing and integration system was developed based on GeoServer. A distributed architecture was adopted to address the data storage in different organizations. WMS and WFS were the main service for data sharing and integration. Applications demonstrate that the system can easily share and integrate various spatial data.

Abstract: In this paper, MODIS-250m vegetation index from first 10-day of March to last 10-day of November in 2010and 2011, land use data and the yield data from 9 counties such as Jiangjin, Wanzhou, Fengdu, Liangping, Qijiang, Liangping, Fuling, Yunyang, Kaixian, Wixi in Chongqing were used. Based on GIS，RS technique and NDVI analysis results, the rice planting area was extracted. Four key growth period of rice such tillering, jointing, heading and milk were selected to establish dynamic assessment model. In nine counties, the average relative error of the remaining 8 counties was between 5.36%-17.09%, and the mean was 12.31% except Qijiang that estimation results and actual yield deviation was too large. The results show that building rice yield estimation model using normalized difference vegetation index was feasible that can realize the dynamic yield estimation of rice.

Abstract: Combining remote sensing techniques with GIS, choosing land using, vegetation coverage and slope as the main affecting factors of soil erosion to monitor and evaluate the soil erosion of Hunyuan County. The research result shows that the soil erosion was seriously, and the soil erosion area that intensity was greater than mild erosion in 2009 is 1635km², occupies 83.2% totally. The severely erosion area is including Northern area, Southeastern mountains and the area between the alluvial plains and the mountains.

Abstract: In measurement data processing, tiny disturbance of the design matrix can enlarge the deviation between least squares estimation solution and true value and the solution distortion arises. By choosing the reasonable parameters according to the regularization method, and Under the constraints of two indicators which are the mean square error and the estimating efficiency，disturb the observation data by varying degrees on the design matrix to determine the relationship between regularization method and ill-conditioned problem in measurement data processing.

Abstract: Beginning from the study on influencing mechanism of urbanization on flood risk, various influencing indicators of flood risk in urbanized areas are researched, presenting that the change of land use, lagged underground drainage, urban heat island effect, accumulative population, wealth and public infrastructure which make cities——the hazard bearing bodies more vulnerable and flood risk increase as well. Supported by RS and GIS, taking Changzhou as an example, the indicators of urbanization shown by two landuse type maps extracted from TM in 2001 and 2008 on flood risk are analyzed together with DEM and distance to discharge channel, it found that urbanized degree and flood risk are a positive correlation, flood risk in more highly urbanized areas is greater, as a consequence of vulnerability and exposure of urban areas increasing.

Abstract: Tianjin is now engaged in the drawing up of the latest five-year plan, and taking this opportunity, this article studies the economic and social development of street regions based on GIS analysis techniques. With the case study of Changzhou Road in Hedong District, the author endeavors to explore a new social development pattern by changing the focus to street regions.

Abstract: Gas insulated switchgear (GIS) is the most important equipment in the power system. The partial discharge (PD) is the main detection method for the insulation failure. Especially, for insulation condition assessment, the pattern recognition technology of partial discharge in GIS is the most important. Acoustic detection of GIS PD is the effective method and it has long application history. The acoustic detection method is very suitable for defects detection in GIS, for it has the advantages of on-line detection and easy realization of locating the defects.The PD pattern characteristic is the key factor for the analysis of defect type. The PD pattern characteristics of four typical defects in GIS based on acoustic detection are studied in this paper. The results provide a test basis for the recognition of PD types and a deeper study of the mechanism of PD.

Abstract: Gas insulated switchgear (GIS) will generate vibration during normal operation for the electromagnetic force. There will be generate abnormal vibration when the contacts are undesirable, the guide rod stressed unevenness. Therefore, it can be effective in fault diagnosis of this machineries through the vibration test of GIS in field. The vibration detection method of GIS equipment in field is studied in this paper, the composition of the vibration detection system is described. The field test has been done using vibration detection system and the test results show that through the vibration signal detected from the GIS equipment, the vibration characteristics of GIS can be clarified and make the fault diagnosis effectively.

Abstract: PDA with RFID functionality, integrated GIS (Geographic Information System), GPRS (General Packet Radio Service) wireless communication technology and Embedded Database Technology developed the substation inspection system based on B/S structure. The system quickly identify equipment identity and accurate records of the defect content of substation equipment according the RIDF. Not only real-time learned inspection personnel in place, but also solve the problem of substation equipment inspection data is not real-time upload. Using the RFID technology improved the substation inspection efficiency and ensured the safe operation of the equipment. This has good promotional value in the power inspection.