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Distribution network is an important part of power system, the biggest feature of the structure is that the end of power network is directly connected to the users, demanding for safety and quality. This article introduces the low voltage distribution network operation theory, designs a low-voltage wiring mode, and by analyzing the disadvantages of this kind of connection, the optimal switching looped network operation is put forward; at the end of the low voltage distribution network flow calculation, by comparing the results of the loop closing operation with the open loop operation, the feasibility and advantages of loop operation is proved.

This paper proposes a scheme of the looped network applied to low-voltage distribution network and introduces the control strategy for looped network in the normal event of a distribution network failure. Besides, the paper shows the superiority of the looped network in reducing the outage time and improving the power distribution reliability.

For energy-saving and consumption-reducing, new energy-saving transformer becomes more and more important. Via an economic evaluation methodology called Total Owning Cost (TOC), this article compares energy-saving transformer with high-energy transformer for examples in the angle of transformer loss and picks up the optimum energy-efficient transformer which can be expected to gain more benefit during transformer life cycle. This article also analyses cost of silicon steel sheet used in the transformer core and benefit in Total Owning Cost (TOC) of upgrading silicon steel sheet which primarily reduces no-load loss. Based on calculated results of Total Owning Cost (TOC) and payback period, the new energy-efficient transformer replacement plan, economic discussion and promotion proposal are brought up.

This paper introduces the method of braking system design for FSAE racing car. Based on the rules of FSAE, the requirements of braking performance were analyzed and the layout was confirmed. The forces of the braking system were analyzed under different braking strengths. The simulation results show that the ?design of the braking system ?can ?meet the strength requirements. Key words: Design ; Simulation ;FSAE; Racing car

This paper presents a novel image trading mechanism based on hybrid watermarking techniques. The removable visible watermarking technique is used to provide the safe preview of the protected media. The fingerprinting is used to trace the illegal distributor. Two kinds of watermarking techniques embed watermarks in DCT domain in order to conform to compression techniques. Experimental results show that image trading mechanism based on hybrid watermarking techniques can protect the image with high quality.

This paper analyzes user needs for active statistical map cartography service and puts forward standardized methods for different class of user needs based on user needs classifying, including the specific user mapping needs, the temporary user input mapping needs as well as active service initiative to provide mapping services based on user characteristics. On this basis, the paper puts forward a unified user needs standardized method by integrating the different standardized method, which gives the unified user need description for the active statistical map cartography service.

Base on the study of interactive collaborative learning system, a construction program of a knowledge-centric interactive collaborative learning system is proposed. The program adopts the knowledge point as the smallest element of teaching resource library, and constructs knowledge model through the relationship between knowledge points. In this paper, the course Computer Organization Principles is taken as an example to build knowledge point repository which is with a certain applicable value and be of guiding significance for the subsequent collaborative learning research.

With the development and formation of networked and digital campus, the characteristic of diversification and complicated have been founded in student’s learning behavior. At the same time, for more broad application of web technology, promoted the ascension of teaching effect and reformation on education teaching method. In this paper a new evaluation analysis model about student's study quality based on web was proposed, and in this model, and in this model the correlation analysis algorithm has been used to verified the danamic relationship between analysis model and student performance, with the description of core technology in this model the validity and practicability of teaching quality monitoring process in the level student was proved.