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961.
Based on the result of NiMH battery performance experiments, changing trend of maximal temperature and difference in temperature of HEV NiMH battery in different SOC and different charging current is analyzed. Considering the working situation of HEV NiMH battery and the theory of battery quick charging, a control strategy for NiMH battery quick charging is described which adapts to HEV regenerative braking system based on Mascc law. By Modeling and simulating the process of NiMH battery quick charging with this strategy, constant voltage charge method and constant current charge method, validates this control strategy.  相似文献   
962.
In this paper,four models are selected as the representatives and applied to nonlinear dynamic analysis program for space frames which is based on the beam-column elements using the finite element flexibility method and the fiber model.Park's test on combined axial and bending columns under cyclic loading are taken as the calibrations,comparisons to material and structural member level are drawn and the analytical results of various models are discussed.  相似文献   
963.
964.
965.
In this paper, the historical reasons of formation of the village inside the city are analyzed. It is indicated that such situation for the villages inside the city are the result of joint action of both the villagers and the government. The foundation of villages inside the city laid on the simple compensation for farmers in confiscating the rural land and lack of intelligence aids. In this paper, the ideas and measures for their reconstruction are put forward based on consideration of the reasons of their formation and difficulties in the reconstruction.  相似文献   
966.
Critical information system in Interact is in face of increasingly security problems. More attention has been focused on the survivability of information system, which is the capability of system to continue its mission even in the presence of damage to the system. The authors first introduce the definition of survivability. According to four function properties of survivability, which are Resistance, Recognition, Recovery, and Adaption, the authors design a model of survivable system structure and then explain survivability requirement, survivability strategy in this model. Additionally, they provide possible technical solutions for the survivability of systems, categorized by different aspects of our survivability strategy.  相似文献   
967.
In this paper, the selection of type, function and technological requirements of EMCS for Shenzhen Underground has been introduced.Based on the investigation for EMCS's worldwide applications and the analysis of practice in Shenzhen Underground, the comparison and selection of PLC and DDC have been done completely.At the same time,the introduction of EMCS is organized by the center level, station level and the spot level.  相似文献   
968.
Hydrodynamic models have been widely applied to river and coastal engineering projects. Understanding the hydrodynamic process is a prerequisite to modeling the pollution and sediment transport process. Hydrodynamic models of varying degrees of complexity should be selected appropriately according to the object of study, physical properties of the flow domain and hydrodynamic features. The essential procedure of hydrodynamic simulation is described in this paper. The main problems such as selection of model dimension in physical space, choice of variables, boundary conditions, initialization, design of computational grid, model resolution, parameterization of smaller scale fluctuations and sub-grid scale processes, model calibration and verification are investigated.  相似文献   
969.
The basic principle of using chromium leach residue as melting flux of blast furnace is introduced in this paper.The reduction thermodynamics of Na 2CrO 4 and chromium oxides in the process of sintering and ironmaking is studied,and the simulating experiments in the laboratory and industrial experiments in 600 m 3 blase furnace are carried out.The results of thermodynamical study and experimental study show that hexavalent chromium ion in the burden can be well eliminated in the process of sintering and ironmaking.  相似文献   
970.
This peper commentaried some of our country comparatively well-known enterprise informationization estimate theory,point out,there is existing the question of informationization estimates,that the achievement can't guarantee "appropriate informationization" establishing and enterprise informationization sustainable development,It propose the three-dimensional enterprise informationization estimate the theory and method,that includes information-based level,information-based quality and information-based development potentiality.  相似文献   
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