Applied Mechanics and Materials Vols. 744-746

Abstract: Based on LabVIEW and CompactRIO platform, a strain measurement system was developed for structure monitoring. The design and achieve method of the system is introduced in detailed. The module of NI 9235 is used to realize the multi-channel signal acquisition at the same time. Data processing and storage online is supported. At last, a test is hold to verify the validity of the system. Comparing with traditional strain measurement system, the system proposed in the paper is stable and reliable. And it is easy to carry, simple operation, performance, high efficiency and good expansibility. The new system with those advantages can adapt to all kinds of complicated and special working environment. It is totally possible that virtual instrument replace the traditional system complete. The new system is worth to promote in application.

Abstract: Surface deformation is a slow and irreversible change. It is impacted by topographic, geologic and human activities. To investigate the spatial distribution of surface deformation in Lanzhou, we used PS-InSAR technique. PS-InSAR is a remote sensing method that can be used to detect surface deformation: an indicator of potential hazards. By capturing these deformations over a period of time, we can get valuable information about impending geohazards, such as landslides. This study focused on using this technique to investigate the distribution and cause of surface deformation in the region around Lanzhou, the capital of Gansu Province, China.

Abstract: Definitions of polar Gauss and stereographic projections are introduced, and the two projections sketches of the Arctic Circle are drawed with the help of Geocart software, according to these two projections formulae. From the angles of real and complex numbers respectively, direct transformations formulae between polar Gauss and stereographic projections are derived through series of derivations. Finally, correctness and reliabilities of the formulae are tested and verified by numerical examples by comparing the calculated coordinates of the projections formulae with the calculated coordinates of the projection transformations formulae. The formulae have universal applicability, and it can provide reference for polar mapping and navigation.

Abstract: Topographic mapping and modeling is one of the most basic and important work in hydraulic engineering construction. This paper present a work flow which contains data measurement, pre-process and post-process with three dimensional laser scan technology. By adopting B-tree and its expansion structure, a multi-level point cloud management and storage method has been established. Then propose a contour generation method based on scan data and the equivalent point interpolation data. A self-adaptive mesh Delaunay algorithm is introduced with point cloud data in order to generate triangular irregular network digital elevation model. Finally, the modeling accuracy and error has been analysis, the results proves this method is with high efficient and accuracy and can be provide assistance for the project construction.

Abstract: Deformation of engineering structures is often measured in order to ensure that the structure is exhibiting a safe behavior. The relationship between deformation and environmental factors is often studied through regression to pick out ambient factors which have major impact on the deformation of the engineering structure. One of the regression assumptions is independence of observations. However, when observations are closer to each other, there is spatial autocorrelation in the observations and the assumption does not hold. Thus it is necessary to test for spatial dependencies before regression. Through the study of a deformation data of a viaduct in Shanghai, China, we find that there exists significant spatial autocorrelation in horizontal and vertical directions, and the vertical deformations exhibit especially strong spatial association.

Abstract: This paper describes the collection and processing of campus images and textures imaging data then resulting into the vector data of campus. Importing vector data into CityEngine software then using CityEngine to model objects on campus. Finally, based on the 3D model, using general software developing kits Microsoft Visual Studio 2010 as the developing platform and employing C# language combining the ArcObjects to make the two objects’ integrated development. Realizing roaming, querying and analyzing etc. Of 2D-3D linkage and greatly enhancing the the intuition and convenience of the campus information management.

Abstract: In the modern geodesy and precise engineering surveying, we often choose ITRF reference frame as the measurement benchmark for research. In some special projects, however, it is difficult to directly get the coordinates of points by GPS, and the visibility conditions between points have also been limited. According to this problem, we propose a new method combining GPS survey and gyrostatic orientation technology, to access the ITRF coordinates of control points indirectly, and analysis and research the related important issues.

Abstract: Since the area of Southwest China crosses the first ladder and the second one ,thus it is featured with precipitous terrains. Owing to such complex factors as deep valleys, steep mountains, varied topography and complex geological structures, it is extremely hard for people to obtain exact leveling data about this area. Therefore ,it is necessary to summarize the geodetic datum and tech of Southwestern mountainous areas, which can be of great reference value for the research of the similar places with regards to its hydrology, geology, geological structure and ground. At the same time this essay will contribute to the study of geological disaster such as earthquake ,landslide and debris flow.

Abstract: In recent years, with the development of modern technologies and safety science, catastrophic accidents tend to be avoided successfully. However, general accidents which cause minor loss or casualties still occur occasionally and hence become main part of all accidents. Therefore, to make effective control of general accidents, fault trees are established based on the analysis of historical general accidents. The influencing factors are roughly divided into human factors and equipment system factors. This paper focuses on human factors and the relationships between the factors and general accidents are analyzed using the improved analytic hierarchy process (AHP) and methods of risk identification. The importance of the factors is thus evaluated. Results of the evaluation are helpful to management.

Abstract: According to the nonlinear dynamic characteristic of coal seam floor water inrush, coal seam floor water inrush risk evaluation which includes 4 first level indicators,14 level two indexes was built based BP neural network. According to the test collection of engineering data, coal seam floor water inrush risk evaluation system based VB and MATLAB is reliable. Application to a mine coal seam No.2 working face was verified. The results show that, the evaluation method in water inrush is feasible, reasonable.