Advanced Materials Research Vol. 681

Abstract: The spatial electric field tester is mainly used for the measurement of high-altitude electrostatic field. The spatial electric field tester will be electrostatically charged during the period it is sent to a certain height by a micro-rocket. In order to study the charge characteristics, the paper analyzes the charging mechanism of the omni-directional spatial electric field tester and builds mathematics model for the friction charging, which is a main factor of the charging process. The numerical calculation and experimental research demonstrate that the friction introduces a slow charge accumulation process for the electric field instrument in the course of its campaign. Under the testing conditions in this paper, the charge amount is 10-11 C within the 6s duration. In order to improve the accuracy of the electric field measurement, a time-frequency analysis method can be adopted to remove the slow-varying electric field signal.

Abstract: In this paper, the combination of Pro\/E and ADAMS to build a virtual prototype model of gear transmission, the dynamic simulation of the gear meshing process, study on dynamic speed, mesh force bearing load, where, for the gear box of the engineering analysis and optimization design. A 3D modeling and designing software, established a parametric model of a gear box of the rack and pinion drive mechanism, which is used in large gantry milling machine XK2425-600. The data interface module MECHANISM/Pro is used to convert the Pro/E model data to ADAMS, and then the virtual prototype is built in it. The rotational speeds, meshing forces, and reactive loads at bearings are obtained by dynamic simulation of the virtual prototype, which can be used in finite element analysis as boundary condition, helped to calculate the strength and stiffness of the box.

Abstract: In this paper, a novel shot boundary detection algorithm is proposed that operates completely in the compressed domain using macroblock type information. While the proposed algorithm can save a lot of computation cost, extensive experiments support that the proposed algorithm also achieves superior performances. Such technique will provide a range of useful applications for on-line video content analysis, processing, and management. Experimental results show that the proposed shot boundary detection algorithm achieve a high recall, precision and F measure.

Abstract: It was presented how to design a management system under FreeBSD. The system can be used in Mechanical devices to authenticate and charge the client through PPPoE based on RADIUS, and built-in batch card generation, management functions, and can the number of user connections and bandwidth control to achieve powerful management capabilities and user self-management capabilities.

Abstract: Traveling salesman problem based on vehicle routing problem in the case, according to the discrete domain specificity, redefine the problem domain to the mapping relationship between particles and related operation rules, and the introduction of self learning operator so that the PSO algorithm can deal with discrete problem. Vehicle Routing Problem (VRP) is research on how to plan the vehicles routes in order to save the transportation cost. Improved Particle Swarm Optimization (PSO) algorithm is proposed to solve the VRP in this paper. To improve the efficiency of the Particle Swarm Optimization, self-learning operator is constructed. Particles are re coded and operate rules are redefined to deal with the discrete problem of VRP. The effectiveness of the proposed algorithm is demonstrated by the simulations.

Abstract: In-wheel motor is an important power unit of electric drive mining trucks, a variety of dynamic performance and thermal issues have important impacts on the whole vehicle performance. In this paper, a model of permanent magnet brushless DC motor (BLDC) cooling system with water-cooled stator structure of electric drive mine dump truck is built. Considering the actual cooling systems, the author modeled the bldc motor and completed the electromagnetic simulation with ansoft software to determine the motor heat source and boundary conditions. This paper simulates the cooling water jacket temperature field with fluent software, and finally validated the feasibility of the design of the motor and its cooling system by experiments.

Abstract: The environment of humidity and high temperature in underground metal mines is not conducive to the heat transfer of converter on electric drive mining truck, and the drive efficiency and lifetime of the equipment are lowered. The article calculated equivalent thermal resistance of radiator, analyzed main factors affecting thermal efficiency. Finite element software was applied to simulate the radiator temperature field of different inlet directions, and then determined fixing angle of air blower which had best cooling effect.

Abstract: Wireless energy transmitting technology provides MEMS inside body with a new power supplying approach. At present, the efficiency and stability of a single- dimensional wireless energy transmitting system are still handicaps in practical applications and need improving. In present paper, two structures of multi-dimensional wireless power are presented and compared each other. Single dimensional primary-three dimensional secondary structure is applied in further research. At last System efficiency is expressed after deduction.

Abstract: Liquid jets in cross air flows are widely used and play an important role in propulsion systems, such as ramjet combustors. Surface waves on the liquid jets in gaseous crossflows have been observed in numerous experiments. Especially for lower gas Webber number, liquid jets breaks up due to the surface waves. However compared with injecting into gas coaxial flow, liquid jet will be deformed in crossflow due to the transverse aerodynamic force. Deformation of jet is investigated by analyzing stress force equilibrium of the cross-section. Though linear instability analysis, dispersion relation and growth rate of surface waves of liquid jet with deformation were derived. According to the present theoretical analysis, the cross-section shape can be deformed to stable ellipse only if the gas velocity was lower than 9m/s for 1mm diameter jet. The maximum growth rate of disturbances takes place at wave number 0.7 approximately, and it will decrease with increasing the jet diameter. The range of instable wave number will expand and the most instable wave number will grow for the deformed jets.

Abstract: The analysis on a two-dimensional infinite anisotropic magnetoelectroelastic solid containing an elliptic hole subjected to a generalized force on the hole surface is performed in this paper. By employing the Stroh formalism, the method of analytical continuation, the technique of conformal mapping, the concept of superposition and the exact electromagnetic boundary conditions, the Green’s functions are obtained.