Advanced Materials Research Vols. 271-273

Abstract: It discourses the methods and procedures of drawing axonometric and intersection while AutoCAD is applied to the complication of drawing teaching material; discusses the techniques of screen-capture and the application of BetterWMF when AutoCAD is inserted into Word Documents. All of the above methods and techniques have great utility value.

Abstract: The difficulty of filtrating network negative information lies in how to classify information correctly. As one of the classification method with the advantage of strong robustness and good understandability in the field of pattern classification, Naïve Bayes has been used widely. A method for filtrating network negative information on the basis of Naïve Bayes, improvement proposals aiming at the disadvantages of Naïve Bayes and amelioration of erroneous judgment of negative information by setting threshold value k have been put forward in this article. The experiment shows that by adjusting threshold value k can the integrity of the system can be optimum and can favorable application effects be achieved.

Abstract: Distributed information resources may fail at any time, thus redundancy can be used to enhance fault tolerant capabilities as a technology. In connection with distributed information resource management, the paper has designed a self-adapted fault-tolerant system taking advantages of redundancy technology. In order to reducing overhead, the system makes use of copy-on-write strategy to find checkpoints and chooses the best checkpoint interval for execution efficiency improvement. The experiment indicates that redundancy system has got good results in application with adaptive, simple, efficient and reliable features.

Abstract: Outline the background and meaning of knowledge base, analyse the role of building it in a virtual community and discuss the problems which will be encountered in the process of building and propose some strategies which can be adopted in the course of structure. In the education field, the virtual community knowledge base is a kind of virtual intellectual resources sharing system in essence that enables individual knowledge into collective. It is a database platform on which college students can display themselves, communicate and share knowledge freely.Currently, ontology-based knowledge base system is the hot topic.

Abstract: To deal with the problem of depletion of iron mine reserves in the area of Xiangshui River in Heilongjiang Province, it is needed to study the geological structure of the region. Through TEM measurements and the corresponding data processing, -350 to -600 m apparent resistivity and the corresponding relationship between different lithologies are set up in the area. According to the regional differences in apparent resistivity lithology, four fracture zones are divided. According to the apparent resistivity difference between rock and ore greater than two orders of magnitude, the spatial location of the ore is explained. With the actual verification of deep drilling, see mine rate reaches 75% so that the efficiency of mining exploration is greatly improved.

Abstract: Synchronization and load balance are the primary problems faced by MMOG server cluster. For synchronization issue, system uses an improved algorithm for optimistic synchronization, at the same time for the contradiction in MMOG between the growing requirements of games resource and the limited load capacity of servers, propose an efficient load balancing algorithm. Experimental results show that the cluster system has higher performance and load balancing capabilities.

Abstract: In order to establish precise grinding cutter model of straight bevel gear, this study projects the spherical involute that forms tooth profile of bevel gear into the involute of circle approximately, and makes a simulation model database of bevel gear according to the principle of mechanical design on the basis of CAD mapping software. With the central projection method, processing devices and cutters of involute straight bevel gear can also be designed which has no concern with modulus. The results show that the establishment of simulation database and processing cutters can greatly facilitate the design and processing of straight bevel gear, greatly reduce the design and finishing costs, and is also helpful to teaching training of gear.

Abstract: With the NDT radioactive isotope widely used in engineering, it puts forward higher requirements for NDT. As the complexity of the device working environment and high reliability requirements, system reliability and security is the focus of the entire design. This NDT uses PT and PLC to operate and control machine and optical encoder to achieve the collection of the source location parameters, DC torque motor drive to ensure jitter-free, long locked rotor, uniform speed drive performance to ensure machine security and stability.

Abstract: Through the study of knowledge management system, combining the current situation of the coal industry information, we have developed a set of Mine Safety Information Management System. The system is a platform that contains the internal knowledge and external knowledge of the coal enterprise management in the era of knowledge economy. The system not only establishes a knowledge map of coal mine safety field, but also includes valuable information collection, automatic classification, information retrieval and relevance association.

Abstract: Founded two input PSS model,by making analysis the theory of Synchro- generator. Use New PSS model to be as a accessorial controlling of Excitation system of Synchro-generator. Founded and simulated the Excitation system including this New PSS in the transient condition based on MATLAB/SIMULINK. Compared the result of simulation, it indicated that the excitation system accessorial controlled by this PSS has nicer roubustness, increased Damp trait of the system,restraining the interference, low frequency oscillation and recover of short cut than the excitation system controlled by PID meth.