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In order to analyze the transient performance of the multiple three-phase synchronous motor (MTSM) operating at synchronous speed, according to the complex mathematical model and the stator inductance matrix feature of the MTSM, its complex equivalent circuit was studied, and the parameter formulas of this equivalent circuit are presented in the general form. The complex equivalent circuit of the MTSM proposed in this paper is formed by many reactance branches which contain an armature reactance of the one set of three-phase winding and several equivalent leakage reactances, and the equivalent leakage reactances are related to the stator currents.

In this paper, frequency domain analysis and application of electrochemical noise of X80 Pipeline Steel in Xinzhou Soil is researched. In the frequency data analysis of electrochemical noise, there are three characteristic parameters. It can be seen from experiments that X80 steel buried in Xinzhou soil with14% moisture content shows that metal corrosion is still not change much. And, it can be inferred that corrosion of X80 pipeline steel in Xinzhou soil with 18% moisture, corrosion is uniform while the morphology is not the uniform , it is the morphology that some pitting are connecting into the film. In Xinzhou soil with 22% moisture, potential PSD figure is different after corrosion happened for one day and three days. Thus, the corrosion type can be determined by high-frequency slope of the linear segment of potential PSD figure.

Power industry informational has become the general trend in new era, for power dispatching operation and mainte-nance center, how to ensure that normal operation of various software and hardware resources is a important yet unsolved problem. The paper makes full use of operation and maintence supervision method, presents a information operation and maintenance fault diagnosis model based on FP-Growth association rules algorithm for power grid enterprise. Firstly, information system operation and maintenance supervision model of power grid is described, according to power enterprise regulations and practical experience of operation and maintenance personnel, it makes a series of operation and maintenance indicators. Then above this foundation detailing the fault diagnosis model is constructed, analyzing diagnosis reasoning process under the different the case of non-compliance indicators, and applying it to the actual operation project that the power grid enterprise information system real-time monitoring plat-form (ISRMP). Finally, preliminary application of ISRMP in Information and Communication Company of Jilin Electric Power.

According to the characteristics of the fringe patterns noise, came up with a small area spin filtering noise cancellation algorithm based on parallel marker technology. It means that preprocess the fringe pattern before spin filtering, then did a median filter and calculated the stripe direction, finally used the extract the fringe direction to spin filtering of the original image. The algorithm can marked several targets in scanning process at the same time. So it has a high efficiency. The algorithm can be used in the multi-frequency heterodyne phase shift technology .And we can use the technology to complete the measurement of complex surfaces. Experimental results show that the method has a distinct advantage in measurement accuracy, measurement speed, and noise immunity.

In order to determine the layout of electric car charging stations, a model for optimizing charging stations location is developed after charging-demand districts are divided, the number of electric vehicles and the center of each charging district are ready. This model takes the minimization of electric vehicles charging stations total cost which includes initial fixed investment costs, operating costs and charging costs as the objective function, some related constraints which include service radius, capacity of charging station etc. are considered. Particle swarm optimization based on hybridization is proposed to solve this problem. The example verifies feasibility of this method.

As a class of nonlinear loads in the power system, electric vehicle chargers will produce a certain harmonic pollution for the grid. Before the construction of charging stations, it is necessary for electric vehicle charger (station) connected to the grid to simulate and predict harmonics. The models of single charger and charge station are built separately in order to simulate and analysis the impact of a single and multiple chargers on power quality. The factors of the harmonic current ratio (HRI) and the current total harmonic distortion (THDI) varied with the charging power and the number of the chargers are discussed and analyzed. The generation mechanism of harmonic counteraction and interaction between the chargers are analyzed. The simulation results show that: because of the impedance of the system and the transformer, the harmonic current ratio (HRI) and the current total harmonic distortion (THDI) both increase firstly to some extent and subsequently decrease gently with the increase of the number of the chargers in the same power charging. This phenomenon has nothing to do with the harmonic counteraction and how that happen is discussed and analysis in this paper. And the phenomenon of harmonics interaction and counteraction occurs with the increase of the number of the chargers in different power charging, and the current total harmonic distortion (THDI) declines and tends to maintain a relatively stable value.

This paper studies energy efficiency of the entire EV charging network.In conjunction with the research, listing first and second level energy efficiency indexs.Determine weight coefficient of the first-level index based on the group-G1 method, with entropy weight method to identify weight coefficient of the second-level index. Finally create the model of energy efficiency assessment of EV charging network with hierarchical synthesis method. Through field measurement and calculation, this model can better impress the energy efficiency level.

In this paper, effects of partial remelting treatment on microstructure and properties of ZL205A alloy were studied in detail. The results show that the grain size of ZL205A alloy decreases at different degree. The grain size increases first and then decreases with increasing of returns content. The average grain size of the primary ZL205A alloy was measured to be about 60 μm, and the good result can be got of the ZL205A alloys with the average particle size of α (Al) phase being about 33 μm after adding 20wt.% returns. The ZL205A alloy with 20 wt.% returns has a considerably high tensile strength and yield strength of 525MPa and 445 MPa, respectively, which is much higher than 501 MPa and 421 MPa of primary ZL205A alloy, meanwhile the elongation level is up to14%.

This paper introduces a novel modeling method using points acquired by a touch probe on a coordinate measuring machine and an optical scanner. An improved iterative closet point algorithm is adopted in order to transform the optical scanning data and the high precision points captured by a touch probe into a common coordinate system. A data merging method is also used to keep the high precision of feature surfaces and then unified into a precise 3D model. Experimental results demonstrate the efficiency of the presented method, which enhances the flexibility of digitization while maintaining the accuracy of feature surfaces.

This paper presents a quantitative method of measuring the volume of material stack.The material stack is divided into many little rectangular columns,then the material stacks volume will be got by calculating each rectangular columns volume.At the same time,a measurement system is designed to achieve the automatic measurement, three-dimensional reconstruction, and volume measurement.

In this paper, the comparation and analysis of the conner detection algorithm used in the three-dimensional reconstruction were made .Also the improvement and optimization to the parameters of harris algorithm were done. It is concluded that the hariis algorithm improved had a better effect ,simpler operation and better stability in the measurement of material stack volume measurement through the experimental results.

In this paper a combined modeling method using digitized points measured by multiple-sensor integrated measuring system with a touch probe and a optical scanning probe is presented. The optical scanning data in the form of triangulated mesh and the high precision data captured by a touch probe on an integrated measuring system are transformed into a common coordinate system by the worktable for registration and improved ICP algorithm. A data merging method is used to keep the high precision of feature surfaces.The merging data is unified into a precise 3D model in CAD software environment based on the strategy for optimization reconstruction. Experimental results demonstrate the efficiency of the proposed method, which enhances the flexibility of digitizing while maintaining the accuracy of feature surfaces.

Two Models for Estimating the Effective Thermal Conductivity (kE) of Multi-Phase Materials Are Comparatively Investigated. the First Model Is the Effective Medium Approximation (EMA), which Is Based on the Extension of the Percolation Theory. the Second Is the Randomly Mixed Model (RMM), a Numerical Method in which All Components Are Seen as Cubech_cubecucube in Shape and Are Randomly Dispersed inside the Space. Two Models Can Be Directly Applied to Multi-Phase Media without Empirical Parameters. Compared with Experimental Data of Food Materials in the Literature, Two Models both Give Good Estimations of the Temperature-Dependent KE.

Hybrid multi-objective particle swarm algorithm is applied to vehicle routing problem and achieved good results, this paper based on the previous work, dynamic inertia weight is added to the particle swarm algorithm with intelligence factors, it improved the global search ability and the capacity of local convergence of the particle swarm algorithm; and the idea of immunity is introduced in the algorithm ,which makes the hybrid multi-objective particle swarm algorithm can effectively discard the repeated solutions in solving vehicle routing problems, this operation can improve the efficiency of the algorithm, and obtain better results under the same conditions.

Aiming at security problem of metal structure of overhead traveling crane, the accident tree is established based on Accident Tree Analysis to further study. The solution of minimizing cut sets and least path sets are obtained by accident tree calculating. Finally several possible measures to prevent structural faults are obtained through final results of the calculation analysis.