Advanced Materials Research Vols. 383-390

Abstract: Each transport mode owns itself technical economy. On the basis of multiple transport mode selection, the paper presents the route optimization model for single-task from one origination to one destination in the fourth party logistics, and gives the solution of Genetic Algorithms. In the algorithms, a length-variant encoding scheme of round number is adopted to represent the selected route, and idea that keeps the best individual is used. The results of experiments show that Genetic Algorithms can solve the route optimization problem based on the selection of multiple transport modes in the fourth party logistics conveniently and effectively.

Abstract: Controllable reactor is the common equipment in the modern power system, which plays an important role in voltage control and reactive power compensation. The core structure of reactor effects the magnetic field distribution in the core and the loss of reactor. In this paper, the models of two kinds of classic reactors are built by the ANSYS command flow method, and explain the differences between magnetic valve controllable reactor and common reactor. This paper points out the advantages of command flow compared with the graphical user interface and the important role of ANSYS finite element analysis in the structural design of reactor.

Abstract: His analytical model is carried out based on the one-dimensional fluid transient theory. In view of the micro-compression of the fluid can change its momentum in the transient process, an improved fluid dynamic model of pipeline is proposed. The characteristic method and the finite difference method are adopted for this simulation. In this paper, The fluid transients of the pipes after servo valve shut down are analyzed. The correctness of the simulation is approved by the comparison of calculation data with experiment data .The results showed that these models give more reasonable descriptions for water hammer and flow oscillation during servo valve starting process and could provide guidance for designs and experiments of the hydraulic pipe system

Abstract: In an excitation control system of some DC generator, there are accidents sometimes thanks to the snobbery unit. To solve these bothersome, based on an snubber unit of the excitation control circuit, namely a Buck converter topology with rectifier bridge, with the filter capacitance and the exciting winding impedance parameter assured, the preferences of the resistance and capacitance of the snubber circuit is investigated by simulation. The result is that it can limit the switching-on peak current of the switch when the snubber resistance and capacitance’s parameters are increased suitably, and the former one can lose more energy on the snubber resistance, then the latter one can reduce the striking current in the snubber resistance at the switching-on time. Finally, the simulation results are provided to verify that the exact selection of the snubber resistance and capacitance’s parameters can make excitation controlling circuit more stable and reliable.

Abstract: Currently in various fields systems are widely used. With the increasing of visitors, the number of concurrent processes raise as System response. In order to ensure system stability for business support, this article analyses data management strategy, database design strategy, application server design strategy, web server design strategy, and implements the enhancing system performance.

Abstract: The firing calibration of Artillery fire control system with closed-loop calibration manner can improve the firing accuracy significantly. The miss distance prediction is the theory core of closed-loop calibration. Whether the prediction algorithm of closed-loop calibration corrects or not is directly related to the calibration’s success or failure. Mainly for the external error sources not caused by fire control computer system, this paper established a closed-loop calibration model based on Kalman filtering algorithm, researched the specific implementation process of algorithm model, and applied the MATLAB software simulating the model. Simulation results show that the closed-loop calibration model based on Kalman filtering algorithm can significantly inhibit firing error and is a feasible algorithm and provides a good theoretical basis for forecasting error.

Abstract: The shunt power capacitors are used as a reactive compensator while vacuum circuit breakers are used to switch shunt capacitors in power grid. To research the high over-voltage during switching off the shunt capacitors and a vacuum circuit beaker restriked, the restriking model is built with three-phase vacuum circuit breakers, considering the capacitors’ energy storage characteristic and asynchronous operating. The over-voltage is harmful to the insulation and life-circle of the equipments and even threatens power system safe and stabile operation. The variation trends of both recovery voltage between the contacts and the capacitors voltage are theoretically deduced. The model based on a 220kV substation of Guangdong grid was built and the most serious case that breakers are restriked in two phases are numbered with EMTP. Compared with theoretical results, simulation results are valid and practical.

Abstract: Based on the orthotropic physical properties of coal cleats, the fluid-solid coupling model for stress sensibility coal seams is established. The equations of the coupling model are solved by using the finite element method. The history matching for JS-3 well in Ordos basin is carried on by using the coupling model. The comparison between calculated results based on the coupling model and the measured values indicates their good agreement, which verifies the accuracy and rationality of the model. The effect of the permeability orthotropic coefficient of coal cleats on the pressure distribution in coal seams is analyzed. The results show that the pressure along the butt cleats direction increases with permeability orthotropic coefficient increasing; The pressure along the face cleats decreases with permeability orthotropic coefficient increasing between 0m~30m and 170m~200m, whereas both increases from 30m to 170m.

Abstract: In order to solve the complexity of the power system planning in the low carbon electricity situation, SE-DEA (Super-Efficiency Data Envelopment Analysis) algorithm is firstly applied to the field of program evaluation sequence voltage and described the evaluation process of voltage level sequence. The network size, the total power loss, integrated power supply reliability, cost in investment and integrated area are introduced to improve the distribution network planning of evaluation index system based on the traditional comprehensive evaluation index system and apply this model program by the corresponding calculated, Through comparative analysis the optimal sequence of voltage options, finally verify that the model is reasonable and effective.

Abstract: The chaos sequence generated by the chaotic map methods usually has unsatisfactory performances. To solve this problem, this paper proposes a novel method with chaos sequence, which blends the Chebyshev chaotic map and one-dimensional chaotic map with infinite collapse in finite interval. Both MATLAB simulations and performance analyses results show that the proposed method has much improved chaotic performances than the single Chebyshev sequence or the chaotic sequence with infinite collapses, by analyzing and simulating the sequence of traversal feature, period doubling properties, Lyapunov exponents, initial value sensitivity, autocorrelation, and the uniformity of sequence.