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261.
262.
ANSYS/LS-DYNA is used to simulate the penetration process of B900FD - 1 bulletproof armor plate, Comparisons and analysis were made between numerical simulation and experiment results. The numerical simulations shows that the Johnson-Cook constitutive model could simulate the physical and mechanical behaviors of ductile materials under shock-loaded. The ultimate-thickness of B9OOFD-1 bulletproof armor plate under 500m/s impact velocity is analyzed by more numerical simulations. 相似文献
263.
Information integrating is the most important key to CIMS,which is the base of the function integrating and all others.Because of so many kinds,so complicated structure,so many different sources and uses that the information in CIMS has,it is necessary to build a popular Information Integrating Model. The model of information integrating in the thesis bases on the enterprise model,which is presented by ISO(International Organization for Standardization).According to the object-oriented method,the process of modeling begins with classifying the information,and then describes the definition of the attributes and the structural relation of those objects. By means of the idea of Encapsulation and Inheritance,the destination of information integrating can be arrive and the model of information integrating can be set up. The model which is based on the share information is helpful to finish the function integrating and the whole CIMS' construction. Moreover,the system which is developed following such program can be reused for many times and the developing circle of CIMS can be apparently shortened,too. 相似文献
264.
In this paper, the water model method is used to optimize the flow behavior of asymmetrical five streams L-type tundish in a steelmaking plant. The results show that the optimization plan is set up with turbulence suppressor T+ vice guide wall D2+ main guide wall with three holes (D1a) which consists of top two holes with 25° inclination and one hole with 30° inclination below. With this plan, the time which the colorants reach to the outlets increases, the difference of response time in all outlets decreases, the peak concentration of the RTD reduces, the existence time of high concentration liquid steel extends, and the ratio of dead zone in each streams reduces. 相似文献
265.
266.
WinSock is a group of API,which is used to transmit data and exchange information on Internet,the Socket Application programme impoldered by users may communicate with other Socket Application programes by Internet. Delphi provides Socket components,which sustains the TCP/IP protocol and makes the Internet programming acquiring much more flexibility.This paper probes that how to realize transmission of files in any format under nonblocking mode between clients and servers by means of Socket components of Delphi. 相似文献
267.
This paper is a part of the research on the lighting techniques of the traditional Chinese buildings in Summer Palace,Beijing,which is a sub-project of the Municipal Research Project on the Correlative Techniques for Beijing's Sustainable Development(Y0604017040391).The work,which the authors took part in,on the most representative Chinese traditional buildings in Summer Palace,is taken as a case study on lighting design and lab simulated experiments and checked by practical result,illustrating a working frame for other similar lighting design works. 相似文献
268.
According to the present research situation of conductive polymer materials- polyaniline (PAN) ,we reviewed the structure and properties of PAN, the effecting factors and the best conditions of electrochemical synthesis and chemical synthesis of PAN , the doping mechanism of PAN, inorganic and organic acid doping,secondary doping, the method of increase soublity and processability of PAN and the broad application of PAN. The development derection and prospect of PAN are pointed out. 相似文献
269.
Fingerprint classification can provide an important indexing mechanism in a fingerprint database. An accurate and consistent classification can greatly reduce fingerprint matching time for large database. In the paper, by combining genetic algorithm and neural network is presented a fingerprint classification algorithm which is able to achieve an accurate classification. By inputting the global feature represented by directional image to three layer neural network trained by genetic algorithm, the fingerprints were classified into six categories: whorl, right loop, left loop, arch, double loop and undiscerning type successfully. 相似文献
270.
The preparation method of transparent film of electrochromism polyaniline on the glass supporter is studied by a dipping polymerization. The electric and optic properities of the resulting film are measured as a function of oxidant,dopant,reaction time and temperature.The optimum technology term is obtained in the normal atmospheric temperature.The experimental result is testified by fuzzy set theory. 相似文献