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Electromagnetic force can seriously damage end windings of large generators, especially involute part of the end windings. This paper focuses on a 1550 MW nuclear generator. 3D time-step finite element method is used to calculate the electromagnetic forces on involute part at both rated and leading phase operation. The most vulnerable parts are pointed out, forces on these parts are analyzed in detail. The difference between forces at rated operation and forces at leading phase operation are presented and the effect of leading phase operation on electromagnetic force is discussed. The conclusions can be references to optimize the design of large generators.

Digital mapping camera is an important tool for modern airborne photogrammetry. Monochromic area CCD which is full frame transfer is selected as image sensor in this paper. Electronic shutter is utilized to eliminate the opening delay of mechanical shutter which will affect the precision of exterior orientation elements acquisition. The equation for calculation displacement of principal point is proposed for TDI forward image motion compensation to compensate principal point shift. Imaging pose control system is designed in order to meet the need for airborne stereo mapping.

Inertia sensing elements are usually adopted as the sensors of velocity stabilization loop in airborne photoelectric equipments, which are constituted stabilized control system, that purpose is reducing the influence of the movement of carrier to visual axis of photoelectric probing system. But gyro, especially the piezoelectricity gyro generates drift, which is the main error source of photoelectric stabilized control system; therefore we need to adopt filtering processing to reduce influence to control system. In this paper, we analyze the characteristic of noise gyro drift, and utilize Kalman filtering technology to conduct filtering processing to output signal of gyro, this method can reduce output noise effectively. The simulation results show that the proposed filtering processing method can improve the low velocity characteristic.

Task allocation is an essential strategy to achieve effective cooperation for swarm robots. Self-organized task allocation strategy is studied and efficient labor division and regulation is realized through local interactions among individual robots based on response threshold model. Local communication mechanism is proposed for the purpose of sharing local sensation information, and the simulation experiments verify that the efficiency of task allocation is improved significantly.

A centralized three dimensional localization algorithm is proposed with the name of NMDS-MEEF, which is based on the location requirements of wireless sensor network used for monitoring large electrical equipment fault. The localization algorithm adopts a changed nonmetric multidimensional scaling in which the iterations process only makes use of the correlated data of one-hop neighbor nodes. The algorithm is more straightforward and practical. The simulation results demonstrate that the algorithm is of great advantages in improving localization accuracy, decreasing the dependence on the density of anchor nodes and reducing the influence by the accuracy of position estimation.

Planar transformers are a good solution for high power density high frequency switching-mode power supplies (SMPS), their research and application are growing in the last decade. Although these kinds of transformers provide a distinct advantage over the traditional transformer, the high frequency parasitic effects have a great influence on the transient performance. This paper presents a method to construct a high frequency planar transformer model with improved accuracy, suitable for design, optimization and circuit simulations. A method of optimizing planar transformerspsila design based on the optimization tool iSIGHT is also presented. Through integrating the circuit simulation tool Saber and the electromagnetic tool Maxwell 3D by iSIGHT, the parasitic effects on planar transformers are studied carefully, and a new method to avoid parasitic oscillations with dangerous high voltage spikes to improve the SMPS performance is established. Simulation results on the optimal design are also included in this paper.

To resolve the problem of complex operation of the linear approximation distance threshold (LADT) algorithm, some improved researches were made to the algorithm by taking the characteristic of electrocardiograph (ECG) signal and the advantages of field programmable gate arrays (FPGA) into account. The paper puts forward a real time compression method with much less mathematical operation and much easier real-time implementation. With the artificial and experimental verification, it turned to be that the arithmetic has the advantages of low distortion and in real time. In the application of improved fast LADT algorithm, the paper designed the hardware system of ECG data compression based on FPGA and the program of the algorithm based on very high speed integrated circuit hardware description language (VHDL). And the experiment results of this system turned to be good performance. The approach can be easily extended to other similar applications.

Distributed artificial intelligence (DAI) has been developed rapidly in industrial application. In this paper, we present a web-based distributed intelligent diagnosis system based on the DAI theory for parallel and cooperative approaches in solving complex diagnostic problems. We first describe the characteristics of the agent and multi-agent systems. Then we analyze the feasibility of applying the agent theory to the diagnosis systems. The characteristics of task processing in the system are described. Four foundation technologies are discussed according to the implementation levels. We presents the general steps of developing a diagnosis system based on the DAI theory.

In the paper, we analyze rejecting periodic interference in partial discharge monitoring on line using a cascade IIR digital wave trap filter. The principle and simple design method are proposed and discussed. Examples and results are given. The results prove the method effective for rejecting periodic interference in lower sampling frequency PD monitoring on line.