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Nonlinear characteristic of servo value is the important factor influencing hydraulic system, the model of electro-hydraulic servo pressure control system is designed. In this model, flux-equation of servo valve is specially applied and some non-linear characteristics are considered. Furthermore, SIMULINK toolbox of MATLAB language software is applied to solve mathematic model and simulation curves of some variables are obtained. The calculation results are in good agreement with the experimental results. 相似文献
85.
The green is as a symbol of no pollution,no public harm and environmental protection. The green automobile is the inevitable results that the automobile technique continuously developes. A new style vehicle--the green automobile is the urgent solicit of environmental protection is developed. The automobile industry can develop continuously. This article mainly discusses the importance of the green auto_mobile's research and development,the development status in quo and prospect of the green auto_mobile technique in the world,and states the relationship between the green automobile technique and environmental protection from green technical system theoretically clarify the study of green automobile,including its design and the system,the manufacture and its technology,the energy,the rebuild engineering and a series of subjects. How to evaluate the cycle and the evaluable mark of the green automobile,the prospect of green automobile are pointed out. 相似文献
86.
A novel edge detection algorithm is proposed by implementing fuzzy image enhancement at different scales.The implement of this algorithm can reduce the negative influence bring from the non-maximum suppression algorithm which select only one threshold.The success of the approach depends on the selection of a general fuzzy operator(GFO) for the enhancement of contrast of region after smoothing of image at different scales.Consequently,it is more obvious that coarse intensity changes are obtained at a large scale whereas the fine details of intensity changes are obtained at a small scale.A pretty performance is obtained by used this work. 相似文献
87.
The research theme of this paper is about how third-party logistics provider design a kind of effective incentive mechanism which can not only avoid the moral hazard behavior of the subcontractor , but also promote subcontractor to raise the serving performance constantly, until obtaining the best TPL performance .Through building bilevel programming model where constructing the Nash equilibrium model this paper, the anthors assume subcontract decision variable as endogenetic variable first, and then analyze the optimal solution with the restraint of Nash equilibrium at the time of decision variable as exogenous variable, push the subcontract relationship research at the principal-agent level into the lay that principal-agent combining with whole contract performance optimal decision. 相似文献
88.
As a key resource, the knowledge management is becoming a research field interested by many researchers. In order to study the mathematics theory base of knowledge expression, in this paper, a knowledge expression model is given. In this model the knowledge system is expressed by multi-tuple, the single knowledge object is expressed by the tuple, a structural expression of knowledge is given using token as example and the application of the model in city water supply pipe network is presented in this paper. 相似文献
89.
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
90.
The policy of public participation in urban planning was first practiced in Europe in the 1960s. After 40 years of development, the policy has become the essential step of city planning in Western countries where as is just at the elementary step in China. For the purpose of knowing the situation about the policy performing in local cities and discussing the feasibility of public participation in urban planning, several kinds of investigation have been done. From the investigation, it is found that although the public participation has already been the important step of urban planning in some city during just several years,there are still many problems. This paper shows a panorama view of this issue. Th describe the future of public participation in e authors will offer some solutions according to the problems and the urban planning. 相似文献