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211.
Yang YuZhe 《保鲜与加工》2005,(3):5
By review of region study in recent development of history science, geography and Sciences of Human Settlements, this paper points out that material collecting without interrelated analyzing as well as focusing on main question and assumption without enough argumentation are main problems in this field now. The method renovation & combination with related subjects are discussed, this paper concludes that strengthen interdisciplinary study with Geography is a key issue in the future development of region study in Sciences of Human Settlements and possible approach to "technical development' and "humanity concern'. 相似文献
212.
The Lexicographic method has subjective and empirical character,so a weighting coefficient is introduced by considering the importance and proportion of each individual object,the preferable result of every individual object can be confirmed by comparing the degree of similarity between the perfect one and the ecumenic one and the Fuzzy optimization will be perfect.The effectiveness of these methods is illustrated by a fuzzy optimal design of the three-bar truss. 相似文献
213.
The tensile strength of high strength bolt is affected by many factors, including prying force. The prying force can result in the increment of bolt force, for which the connection failed ahead of time. Several methods are presented for calculating the prying force. In the China's "Code for Design of Steel Structure" (GB50017), there is no formula for calculation of prying force and a factor of 0.8 is considered in formula for tensile strength of bolt for taking the prying force into account. It is proposed that the design value of tensile resistance for high strength bolt should be increased. 相似文献
214.
WU Wen xue 《保鲜与加工》2001,(5):124-129
For the stability analysis of the reinforced earth retaining wall with cohesive backfill, this paper assumes that the state of failure surface is circular sliding surface and the bearing capacity is straight line relation with capacity and length of the reinforcement strip. These formulas agree with actual state of the reinforced earth retaining wall with cohesive backfill and result in saving reinforcement material in the design. 相似文献
215.
216.
The author introduces a method and experimental procedures that determine dn/dc,molecular weight and its distribution of the hyroxyethyl starch(HES) by means of Gel Permeation Chromatography-Refractive index-Multi-angle laser light scattering detection(GPC-RI-MALLS)techniques.The key experimental technique and results are discussed.The method takes CH3COOH/CH3COONa as mobile phase and solvent.The experiment gets satisfactory results.It can be used as a routine method to determine the hyroxyethyl starch(HES) molecular weight and its distribution. 相似文献
217.
The conjugate direction method for solving the unconstrained optimization problem is extended to solving the constrained optimization problem by method of differential geomtry.By inducing a new class of affine connections on a constrained sub-manifold, the primary constrched optilnhation problem is converted to a unconstrained local quadratic programming problem.Based on the definition and construction of a new class of generalized conjugate directions, it isproved that optimum value of the primary constrained optimization problem must be located on thegeodesic line which is formed by the conjugate directions mentioned above and can be reached withinfinite searching step. Therefore a new curve search algorithm with generalized conjugate directions isput forward. 相似文献
218.
219.
In this paper, a new method of researching; the site dupleface dynamic balance of machine rigid rotator, namely duple test weightmethod is presented. Weight the new method against the existing method,namely single test weight method [1], both the efficiency increasing and theenergy-consumming dicreasing would be forty percent and over, with thebasic points of vibration theory, the formula of calculating weight andposition of the duple face dynamic unbalance of a rotator by means ofapplying the duple test weight is developed in detail. The method in handll-ing distinct bearing form is also discussed. Rightness of the new method isproved out by the living example of the simulant contrast testing carried outn the dynamic balance test machine and the site balance for a rotatorsystem of motor. 相似文献
220.
Luo Jizhang Chongqing Institute of Architecture EngineeringLiu Zhengbao Nanyang University 《保鲜与加工》1991,(2)
In this paper,the interaction between foundation withcavern and frame structure is studied by the coupling methods of BEMand FEM.On the interface between the foundation and structure,thecoupling analysis needs to satisfy both the condition of displacementcompatibility and force equilibrum.A calculating program for two-dim-ensional problem is worked out in the computer,SIEMENS 7570C.Twoengineering examples are calculated and the results are compared withthose obtained by the comventional simplified method and with the observedresults from the engieering structures.It indicates that it is necessaryfor the weak rock foundation with shallow cavern,in the buried depth,to take the interaction into account. 相似文献