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981.
982.
王培芝 《中南林业科技大学学报(自然科学版)》1992,(2)
本文主要依据弹性体在外力作用下发生变形时,各点处产生弹性应变能的概念,探讨了材料力学教科书中常用的强度理论的提法,提出了主剪应变能强度理论,这一理论除了具有概念较为确切、清晰等优点外,还可以推论到其他强度理论及材料力学的其他内容上。 相似文献
983.
984.
PU Yong-jian 《保鲜与加工》2004,(2):145-149
We have put forward a theory that the probation period mechanism have an information screening function when a company is inviting applications for job, which would be a supplement for the spence model. One of the merits of the model is that it could screen the informations of employee's capacity when there are fewer differences between the capacities of employees. This paper also has proved that option mechanism has a information screening effect and the compose of option and probation period mechanism could decrease the screen cost of a company. We have derived the mathematical Principles of probation period mechanism and the compose of option and probation period mechanism design in the paper. 相似文献
985.
986.
The strategies of portfolio insurance are introduced according to its principles and design thinking.The(authors) give the simple mathematical models and practical processes of option-based portfolio insurance(OBPI),constant mix(CM),constant proportion portfolio insurance(CPPI),and time-invariant portfolio protection(TIPP),and use risky assets containing 180 index's stocks of Shang-hai Stock Exchange and risky-free assets containing bonds to form portfolio to do empirical simulating.Based on the results,they analyze the above strategies comparatively,gives the(related) investment suggestion,and shows how to avoid risk without restriction on profit. 相似文献
987.
Administrative monopoly in China is analyzed with microeconomics tools such as rent-seeking theory, comparative advantage theory and game theory. A rent seeking model is given to study administrative monopoly. Futhermore, the authors propose that the barriers brought by administrative monopoly not only increase consumers burden, but also make enterprises run with high cost and low efficiency, and optimal resource distribution can not be done. Administrative monopoly can not be eliminated unless administrative monopoly is regulated within anti-monopoly law and its legal liability is enhanced, which is proved with game theory. In order to solve administrative monopoly, China should construct a law system concluding anti-monopoly law and administrative law as a reinforce. 相似文献
988.
Wu Ning Zhu Yongjun 《保鲜与加工》1991,(1):19-24
A new model for frequency - domain analysis - the real resistive model which is based on Complex Network Theory is proposed in this paper. The network equations formed with the new model without contain complex numbers because there are only sources and resirtive elements in the model. A CAA algorithm for frequency analysis by using the new model is also given. It is shown that the trouble with the complex operation in the traditional algorithm has been avoided. The algorithm presented in this paper is simple and convenient,hence it is easy to popularize. 相似文献
989.
The authors use the ideas and methods of the game theory to reveal that, under the condition of dissymmetrical information, it can't form an effective cooperative relationship among supervisor organization, the shareholders and the enterprises. In the capital market, we explain the cooperative conditions and determinants researched. Only through strengthening the force of punishment towards providing the false information and increasing the benefit received by providing the real information, the enthusiasm of the founders' providing the false information drops, and the necessity of the supervisor organization's checking decreases. Finally, we give some suggestions about the construction and consummating of the capital market of the enterprise. 相似文献
990.
The key of motor control is to control motor's torque essentially.Direct torque control,which emerged after the field-oriented control,directly stresses the instantaneous torque control of induction machine,which avoids some problems existing in field-oriented control,thus,it gets more attention.In conventional direct torque control system,switch vector is selected directly by the errors of stator flux-linkage and torque,after introducing fuzzy logic,optimal selecting switch state is realized by various strategies by distinguishing the grade of the errors of stator flux-linkage and torque,the dynamic and steady state performances of induction motors are improved.This paper presents a design method of the fuzzy controller.Simulation results demonstrate that it is effective,the stator currents pulsation at start-up and the torque pulsation are decreased. 相似文献