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81.
Hu Lide Yang Dan Wang Shilong 《保鲜与加工》1993,(6):58-64
After researching the function requirements of the planning and scheduling in manufacturing cells, the paper advanced a control structure with three phases, i. e. planning , scheduling and dispatching. The paper represented in detail the main purposes, requirements and scheduling actions in each phase. It suits to general machining FMSs. 相似文献
82.
Wang Yongyue 《保鲜与加工》1996,(1):27-31
The secant rigidity is used for the are-length method to solve the nonlinear finite elements problems. The advantage of this method is unnecessary of calculating the initial resistance term caused by the incremental step. The computational work is less and the programing is easier as compared with initial are-length method. This method can be widely used to solve nonlinear problems. 相似文献
83.
84.
Polylactide,a biodegradable polymer, is an important biomedical meaterial. The synthesis of lactide from lactic acid is the key dimer of polylactide,unevitably affacting the polymerized process and the quality. Present work improves synthesis process of lactide. The synthesized factors are discussed, the reactive time is shortened and the quality of resultant is also raised. 相似文献
85.
Based on the analysis and study on some existed models for two-dimensional Guillotine Cutting-Stock problem, it is pointed out that some kinds of the models may miss some good cutting patterns,and some may result in inadequate solutions because of only considering the patterns with the smallest waste. A kind of revised two-dimensional cutting-stock models are developed,which transform the two-dimensional problem into the one-dimensional one using the dimension-decreasing heuristic method and whose initial patterns are considered comprehensively. In this kind of models, not only the least waste,but also the other constraints,such as the demands and the relative area of the order plates are considered. 相似文献
86.
This poper sets up a new Neural Network Fuzzy inference Cooperation system which is based on fuzzy inference principle in Expert Systems,take advantage of the powerful learning function, the little sensitivity to input layer's samples,and the fast convergence and so on in FCBP and take advantage of the good sort property and good suit property to fuzzy value in MFART Network. 相似文献
87.
This paper presents a new practical criterion for voltage stability based on the real-time information at the substation and the quasi-time information from power system.By using the criterion,it is effective to predict the bus voltage stability margin.This is of great importance to raise the security operation level and prevent voltage collapse.The practical criterion for voltage stability is tested on the IEEE-14-bus test system.It needs less calculation time and is very suitable for real-time control of power systems. 相似文献
88.
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
89.
The adsorption quantities of methane on anthracite and its char at different tem-perature and time were measured by using volumetric niethod. The corresponding adsorption formula-is presented. The experimental results have shown that the diffusion acti-vation energies of methane in the anthracite and its char are 14.3 kJ/mol and 26. 3 kJ/mol.It issuggested that the diffusion process of methane could be the flow through the micropores in the an-thracite and its char. 相似文献
90.