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231.
To develop the public traffic and setup a city form coordinated with the development of the public traffic has become a common sense in the full achievement of the city sustainable development. Due to the particularity of the exploration procedure and some difficulties in urban development, the policy on developing public traffic has not been realized in our country. Now it is on edge to solve these problems, particularly in the new area of development. In this article, the authors intend to find a practical way of establishing a ciity development mode with adapting the public traffic development by contrasting Lujiazui new area in Shanghai and the new east area in Chongqing. 相似文献
232.
According to the needs of setting up a professional system based on motorcycle design,the CBR(case based reasoning) and RBR(rule based reasoning) methods are introduced.After discussing the difference between the two kinds of reasoning,a method of integrating them into the motorcycle design flow is put forward to realize the design reusable technology and improve the design efficiency,by using the CBR in the step of selecting the similar motorcycle and the RBR in project's modification according to correlative rules. 相似文献
233.
Housing industry is a prop industry with great potential, but it is restricted by shortage of funds. So it is necessary to probe the financing system of housing industrialization in China. This paper puts forward a financing plan for the international cooperative project in industrialized housing in Chongqing. Furthermore, it investigates the concrete financing system of the whole housing industry. 相似文献
234.
235.
The solution of polarization field strength in ellipsoid and a homogeneous dielectric in condition of a constant external field is obtained with strict derivation and ellipsoidal coordinate. The conclusion that some textbooks given: the direction of polarization field strength with the direction of external field holds strict anti-parallel must be supplemented with additive certain conditions, otherwise it will not be correct. By means of the latticework and the step change calculation, the angle value of polarization vector with the external field is calculated and the changing situation about the angle value with the change of three half axes of ellipsoid is analysied. 相似文献
236.
Many factors affect the propagation of ultra high frequency(UHF) signals caused by partial discharge(PD) on the waveforms and energy of signals in transformer.To investigate the relationshi Pof factors and UHF signals,simulation model of transformer for PD study are established.UHF signals in simulation model of transformer caused by PD are calculated using finite difference time domain method.By means of amplitude and cumulative energy plot of simulation signals,and combing the measured result,the following factors:distance between PD source and detection position,different metallic conductor position around detection position and iron core and winding are researched,which contribute to comprehend the propagation characteristic of UHF signals and detect UHF signals accurately. 相似文献
237.
238.
Some conclusions were drawn from two groups of in-site tests on concrete pile composite foundations. In the tests, it was found that the pressure under the rigid loading slab is different, in which the pressure under the center of the slab is the less and under the edge of the slab is the biggest. The pile-soil stress ratio is not a constant; it increases with the adding of the load. Most of the pile-soil ratio vary from 9 to 13 in these tests and the load that the piles share can be more than seventy percent of the whole load. It was proved that the bearing capacity of the concrete pile composite foundation is high with a little settlement, so it will be used more and more in the future. 相似文献
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240.