Advanced Materials Research Vols. 779-780

Abstract: The control of nonlinear decoupling between the electromagnetic torque and radial levitation force is the key of the stable suspend operation of bearingless induction motor. An optimized algorithm for stator flux oriented control with direct solution of d-axis current is proposed. This method overcomes the problems that the conventional stator flux oriented control which must work with decouple regulator and is influenced by time-delay of decouple regulator. The control of suspend model imports the feedback control of unilateral magnetic-force to reduce the errors about the delay and interference of system. The simulation results show that the motor has excellent dynamic performance and stability.

Abstract: Thickness thinning repair analog simulated using fluid mechanics research tool ANSYS-CFX of mixed-flow turbine runner blade,Through the three-dimensional flow and numerical calculation and analysis of energy distribution on the blade after featheredging. Leaf blade repair thickness thinning after 0.5CM in the cavitation performance, vibration performance and operation performance of the performance indicators to achieve the ideal state, The new method for reducing wheel vibration, vortex row, There is a certain positive significance in improving the efficiency of turbine, make full use of new energy.

Abstract: Port container throughput forecast is an important work for wharf project which has further influence on the development of ports. In this paper, we simply introduce the grey system theory and the grey markov model. Further more, we make a forecast for the container throughput by using grey markov model and the result can offer the decision-making bases for relevant department.

Abstract: On the basis of the theory and method of extenics and to evaluate the safety level of urban road intersections quantitatively, those are selected that infrastructure, signal lamp, conflict rate in all 3 categories of 9 indicators, meanwhile, the matter element model of safety evaluation for urban road intersections is put forward based on extenics, and the objective assessment with multiobjects for urban road intersections safety level is transformed into the single objective decision which is convenient to be estimated and compared. Then by calculating the comprehensive correlative degree it is analyzed that each index factor has influence on intersection safety. The results of numerical analysis shows that the extension method can much better evaluate intersection safety level for improving intersection safety to provide efficient and valued basis for traffic management department to make decision.

Abstract: The principal aim of this paper is to determine the reasonable design parameters of high-speed railway vibration attenuation. The orthogonal test method is used to design the test of ground vibration induced by high-speed train. Four main factors that impact the maximum ground vertical vibration level are selected, and different values are given to each factor, so 8 groups of combinations can be obtained by using orthogonal test technique. Each group test data of the maximum ground vertical vibration level can be obtained by conducting vehicle testing on-track. In this paper, the primary and secondary factors that impact the maximum ground vertical vibration level are determined by range analysis. Moreover, the neural network theory is used to establish a model of the ground vertical vibration level, and this model can be trained and verified by the test data. The impact factors can be predicted by the method of combining orthogonal test and neural network concerning the specified vibration limit, and the value of maximum ground vertical vibration level with the predicted factors meets the requirement of accuracy. The conclusions provide a valuable reference to the vibration attenuation design of the high-speed railway.

Abstract: To solve the brake thermal recession of traditional brake, an integrated brake of double-disc frictional and electromagnetic was proposed. For a certain car, the integrated brake of double-disc frictional with electromagnetic was designed. Through simulation and bench test, torque characteristic of the integrated brake was studied. Results showed that the theoretical designing curve agreed well with the experimental curve. The electromagnetic brake device of the integrated brake can provide a braking torque for 180-202N.m, thus it can effectively improve the brake thermal recession.

Abstract: In order to provide a theory algorithm for simulation and reconstruction analysis of automobile two-dimensional eccentric collision accidents, the applicability problems of the traditional dynamics model and trajectory model in this kind of accident were analyzed in theory respectively. Using PC-Crash software and the traditional models, a real accident case was reconstructed and analyzed. The comparative study between the reconstruction analysis results and the vehicles traces remained in the accident scene was conducted. According to the comparative study, reliabilities of the traditional models were verified.

Abstract: This study takes the long highway as the object, discuss generally fire, ventilation, lighting, tunnel geological and other key technical issues, and analyze the importance of these disasters' prevention and control. Via the study of the tunnel fires' characteristics and damages, this thesis puts forward some views on the construction of fire access doors and maintenance, and works out the corresponding fire prevention measures.

Abstract: Ship navigation performance more and more attention in real sea conditions.To study the properties of ship motion in waves, Applling hydrodynamics calculation software for AQWA-line and AQWA-AGS modules and taking into account the role of random wave load, 2450DWT a small oil tanker in simulation and analysis of a campaign response under sea conditions, Calculate shipping in several waves under the angle of vertical and horizontal swing, heave, pitch, roll and the first rolling response amplitude operators of RAOs, additional parameters such as quality and radiation damping. Application of spectrum analysis method, ITTC wave with two parameters, which strike the spectral density of ship motion, and finally using Excel to calculate sprawling forecast prediction of ship under irregular wave.

Abstract: With the rapid development of the freeway, preventive work of freeway traffic faces larger and larger test. This paper adopts 1561 cases of traffic accidents in the Jiliao-freeway in past 5 years to find out the factors that affect safety. The study found out some factors which cause freeway traffic accidents, they are time, weather, the number of patrol vehicles and monitoring, age and attribution of the accident driver. The paper studies the management problems and puts forward on the countermeasures and suggestions, especially the problem of freeway traffic police burnout. This problem which involves in freeway traffic accident prevention will reach a new level and lay the foundation for the future research work.