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211.
Considering the character of slope resistant engineering invest benefit, in line with security and economy balmaced, combining initial investment and anticipated hazard loss, disaster resistant engineering should be satisfied with the criterion of minimum cost. Decision tree model is adopted as analyzing means, and risk decision-making of slope design is carried out. Project input-output radio adopting dynamic analysis can reflect project investment benefit more accurately. At last this paper analyzes some questions in process of slope resistant engineering with benefits enumerate.  相似文献   
212.
With the development of circulating fluidized bed boiler(CFB),the study field of external heat exchanger(EHE) is greater in extent and degree.In order to research the working process of EHE,the model which deals with flow and heat transfer of EHE for 300MW CFB of Dong Fang Boiler Grou PCo.Ltd.is presented.Based on the cell modeling theory,the EHE is divided into several chamber by heating surfaces.The mass and energy conservation equations of each cell have been developed according to some reasonable assumption.The complete mathematical model has been compiled by Fortran and solved by classical Algorithm of Runge-Kutta.The static test and perturbation experiment of simulating model has been performed.The simulation results show that the model has been reached the steady state rapidly,the dynamic responses are reasonable and the modeling presented in the paper is reliable and appropriate.  相似文献   
213.
214.
This article briefly introduces the principle and the character of the leverage buyouts since the rate of finance lever and the risk is high in the LBO, this article gives a game-theory analysis on the financing process between the purchaser and the investor in LBO by using the ROSS model. It is expected that some beneficial proposal to either side can be put forward by parting the equilibrium.in the last, it poses that LBO can be a way of broadening the financing channel on the annexation between the enterprises in our country.  相似文献   
215.
This paper introduces the modeling of Unified Modeling Language with use case diagram and active diagram based on Rational Unified Process for Equipment Managemet Information System. It discusses the modeling mechanism and character of UML and develops the Computer Equipment management Information System Based Web using Rational Rose of UML CASE Tool. First, it is describe the authors how to analyze the structure of organize and build the model of structure organize. Second, they abstract the workflow of main operation in organize and build workflow model by active diagram. Finally, they abstract actor, use case with case diagram and finish the requirement model.  相似文献   
216.
In this paper, the machine( physical) parameters of the alternator system are on-line estimated on the basis of the derived system continuous-tims model, using Recursive Least-squares Estimation and Inverse Calculation Method proposed by Authors. Therefore, the estimated machine parameters can effectively track the changes of their true values and accomplish the fault detection for the alternator system. This paper gives a new way for machne parameter estimation and fault detection of the alternator systems.  相似文献   
217.
Mathematical model of power frequency electric field is established based on Charge Simulation Method(CSM) to analyze power frequency electric field caused by EHV lines with overhead ground wires and its effect, which are entering the megalopolis. Calculative method on the electric field under the transmission lines is analyzed and validated. According to the criterion of environmental evaluation, the distributing characteristic of electric field is summarized, in case of various arrangement manners of lines. At last, some advice and methods of eliminating electric field under the transmission lines entering the megalopolis is proposed with regard to protecting environment.  相似文献   
218.
Based on the data of dynamic tests of small single-storey steel frames,the suitability of simplified hi-linear restoring force model in earthquake response analysis is discussed, and the Maximum displacement response MD, the sum of squares of the displacements in the whole vibrating history SSD, and the total dissipated energy EI are considered respectively as equivalent object.  相似文献   
219.
In order to overcome some technical difficulties,we adopt ingenously the grey models combined with the quantitative analog method,and select the Dan Jiangkou Project which has accumulated practical operation data for a long time as the analog project to predict the economic influence for the circumjacent reservoir region of the Longtan hydropower project.On the basis of analog we have built various industrial economic grey models,and compare them with the corresponding predictions for the unconstructed reservoir case.The predictions of the former are greatly larger than the later ones.and hence provides a certain scientific basis for the central leaders to make a decision for constructing the huge hydropower project ultimateiy.  相似文献   
220.
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