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151.
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153.
Jinshajiang River, which has a drainage area of 485,100 Km 2, average flux of 142.9 billion m 3, and soil conveyance of 247 million t/a, is the largest branch of Changjiang river. It is also the largest soil resource of the Three Gorges reservoir and upper reach of Changjiang River. To research the development and trend of Jinshajiang sediment not only has a relation to Jinshajiang water resource strategy, but also has important meaning to control the silt in Three Gorges reservoir and the Changjiang water resource development. The paper statistically analyses the flux and sediment conveyance of the Pingshan station, which is the primary hydrological station in the Jinshajiang River Drainage Area. Through several non-parameter statistical methods such as Spearman order correlativity check, Kendell order correlativity check, and linear regression check, the paper concludes that the sediment evolvement trend of Pingshan station is not distinct. 相似文献
154.
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
155.
The vendor selection directly relatives to the procurement quality and influences the competition of the corporation in the supply chains. It is important and practical to study the vendor selection method. The measuring criteria and the method for vendor selection are analyzed. The authors put forward an new method which is combined with both the advantage of analytic hierarchy process (AHP ) and random disposal of data envelopment analysis ( DEA) for vendor selection. It introduces a random variable which solves the disadvantage of the weigh value in DEA which convert subjective estimation to objective opinion in the course of the vendor selecting. The method can improve the reliability of the vendor selection. 相似文献
156.
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
157.
With the rapid increase of the Internet user and widely application of Web,the current network technology is facing great challenge. More and more multimedia operations occupy plenty of bandwidth,and result in the network congestion. Therefore,people begin to use QoS to utilize the bandwidth effectively,and ensure the transport of the emergent operation data. The paper introduces the protocols and basic components of QoS,then expatiates the conception and the basic principles of policy control QoS, moreover,emphasizes the structure model of policy control QoS and how it runs. At last,it introduces the transport process of data packets under the control of policies in a policy control QoS system,and how to make the policies in the real world. 相似文献
158.
In general, the process of synthesis the refractory nanoparticles Is classified as solid state, liquid state and gaseity. The new progress and development in the study of refractory nanoparticles are investigated. The synthesis technology of the refrectory nanoparticle in liquid state is discussed mostly. The refrectory nanoparticles is synthesized by the liquid state. The characteristics and the structure of the refrectory nanoparticles have been studied in this paper. 相似文献
159.
Adopting the element SOLID65 and LINK8 in the general finite element analysis software ANSYS and fiber model beam-column element based on finite element flexibility method respectively, the comparative analysis of the cross, L and T-shaped RC columns under compression, bending, shear and torsion with flange width-thickness ratio of 4:1 is carried out. The applicability of plane section assumption in the nonlinear analysis is discussed primarily, which shows that it is feasible on the whole for shaped RC columns with flange width-thickness ratio equal to or smaller than 4:1. 相似文献
160.
This paper empirically discusses the mechanism of China Neutral Technology by Embodied Spillovers from North America, and the effect on China economic growth. The simulations show that the effects of technology spillovers on both the innovating and the receiving economies depend on SS and AC. The three sectors spillovers of North America can improve China's Hicks-neutral technological progress, but only the third industry can increase the output of same industry of China, and decrease the output of other two industries. Based on the simulations, some advices are given on China trade policy. 相似文献