Applied Mechanics and Materials Vols. 457-458

Abstract: It will stir up the vibration of asphalt deck surfacing when the Vehicles pass through the steel bridge deck. The research of the moving vehicles vibration characteristics of the deck surfacing has been one enthusiastic concern. By the time history analysis method of finite element, the paper studied the dynamic response of the deck surfacing in different speeds of vehicles, and then analyzed the effect of the deck surfacing by different speeds.

Abstract: Error modeling and analysis can provide some important direction to the machining precision control. According to the characteristics of topology structure on machine tool, a space error model of machine tool and detailed modeling method are presented in this paper, which are based on three-dimensional vector chain. Taking a lathe as an example, the application method of this model in error sensitivity analysis is introduced. By this model, the relationship between the relative error of workpiece-tool and each source error can be solved by ordinary vector operation, and the analysis efficiency should be enhanced greatly.

Abstract: Fortunately recent years the developments of CAD/CAE technique in the mold industry have been obtained great progress and large-scale application due to its low-cost, high-efficient, all-position and all-procedure parameters designing and simulation function. According to the structural characteristics of the Rubik's cube center shaft, using Moldflow software to analyze and simulate the injection molding process, including gate location, filling, cooling and warping. Through comparison analysis under different conditions of injection molding process, the optimum technological parameter is determined. Finally, UG software is used to build up the model of injection mold.

Abstract: The stability, comfort and safety of vehicles depend largely on the aerodynamic characteristics of the vehicle in high speed. As the turbulence model plays a decisive factor in the numerical simulation of aerodynamic characteristics, a simulation analysis of Ahmed model with a slant angle of is carried out by the XFlow software. Then the paper presents the changes of aerodynamic parameters relative to the experimental values with four turbulence models: Spalart-Allmaras model, WALE model, Dynamic Smagorinsky model and Smagorinsky model. It is found that the result of simulation with Smagorinsky model is in good agreement with experimental value, and the simulation of the wake vortex separation is consistent with the actual phenomenon. The Smagorinsky turbulence model has a good simulation precision.

Abstract: At present, large section conductors applied in domestic ±800kV ultra-high DC power transmission line consist of 6×720mm², 6×900mm² and 6×1000mm² conductors. This paper analyzes initial engineering investment and mechanical performance of 6×JL1/G2A-720/50, 6×JL1/G3A-900/40, 6×JL1/G3A-1000/45, 6×JL1/G2A-1250/70 and 6×JL1/G2A-1520/125 conductor plans, carry out economic comparison of the whole life period of these 5 conductor plans, demonstrate economic of 6×JL1/G2A-1250/70, and 6×JL1/G2A-1520/125 conductor plans in ±800kV ultra-high DC power transmission line is more advantageous when annual loss hours is too high, and the 6×JL1/G2A-1250/70 plan can save initial investment of engineering compared to the 6×JL1/G2A-1520/125 plan.

Abstract: Multivariate statistical analysis explains the huge and complicated current situation of the original data efficiently, concisely, and explicitly. It simplifies the original data into representative factors, or bases on the similarity between data to cluster and identify clustering outcome. In this study, the statistical software SPSS 12.0 was used to perform the multivariate statistical analysis to evaluate characteristics of groundwater quality at an industrial park site located in Kaohsiung, Taiwan. Results from the principal component analysis (PCA) and factor analyses (FA) show that seven principal components could be compiled from 20 groundwater quality indicators obtained from groundwater analyses, which included background factor, salt residua factor, hardness factor, ethylene chloride factor, alkalinity factor, organic pollutant factor, and chloroform factor. Among the seven principal components, the major influencing components were salinization factor and acid-base factor. Results show that the seven principal component factors were able to represent 89.6% of the total variability for 20 different groundwater quality indicators. Groundwater monitoring wells were classified into seven groups according to the partition of homogeneity and similarity using the two-phase cluster analysis (CA). The clustering results indicate that chlorides such as 1,1-dichloroethylene, 1,1-dichloroethane, and cis-1,2-dichloroethylene had the highest concentrations among the clusters. This indicates that groundwater at nearby areas may be polluted by chlorinated organic compounds. Results from the correlation analysis by Fisher coefficient formula show that the cluster results of seven groups of groundwater wells had 100 and 80% accuracies using discriminant and cross-validation analyses, respectively. This implies that high accuracy can be obtained when discriminant and cluster analyses are applied for data evaluation.

Abstract: Aiming at the situation of the low power factor of coal mine power system, this paper puts forward an integrated distribution scheme of reactive power compensation based on SVG. In this paper, not only the disadvantageous influences of reactive power of coal mine power network are analyzed, but also the working principle and advantages of SVG are introduced. This paper proposes a distribution scheme of three-level reactive power compensation, which is to compensate in the sides of high voltage, high-low voltage power distribution and the long-distance high-power loads. According to the results of theoretical calculation and MATLAB simulation, the scheme can reduce the power loss and increase the power factor, so the power quality of coal mine can be improved.

Abstract: This article gathers 16 factors which influence the duration of public construction project on the basis of research and analysis, and forms hierarchical relationships and causal relationships of the factors through improved interpretive structural model. Finally, comes up with several recommendations on the issue, further，the research and discussion on public construction project control and optimization of construction duration of our country are carried out.

Abstract: According to the Intricate Dynamic Relationship of the Duration Management System，the Paper Identified Risk Factors for the Object.Then Established a Comprehensive Integrated Public Construction Project Duration Risk Assessment Model with the Application of Game Theory-Based Weighting Method. the Model is Validated Effective and Reasonable through Simulation Analysis. and it also Provides a New way of Thinking in the Duration Risk Assessment.

Abstract: For the characteristics of serious formation damage and insufficient injecting in injection wells in the water flooding development process in low permeability oilfield, it carries the analysis of reasons for forming low efficient injection wells and the development of acidizing disentanglement agent. Through core damage experiment of wellhead sewage in S oilfield, formation damage is mainly caused by excessive levels of suspended matters and the multiple of exceeding standards is 45.3. Based on the result of core damage experiment and actual oilfield production data, the variation of apparent injectivity index in low efficient injection wells is researched. The research result indicates that formation damage radius of pollution wells is about 20m in this oilfield. Based on formation damage condition of this oilfield, compound acid is developed, which has the properties of strong penetration, retarding reaction velocity and strong-chelating. Plug removal experiment indicates that the recovery rate of core permeability is about 100% using developed compound acid.