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991.
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   
992.
993.
A optimal design with whole structure parameters and its program are carried out. A reasonable model is established. Using the method a optimal design with whole structure parameters by original parameters of American P&H2300xp excavator was calculated. The size,carried out by the method,approximates to the size of P&H2300xp excavator very well.  相似文献   
994.
This paper presents a matrix structural analysis of variable stiffness on the complete loading history of prestressed concrete grids with unbonded tendons. A model of torsional rigidity affected by moment is derived by the analogy of space truss, and the effect of torque on flexural rigidity is also studied. In order to calculate the increment of stresses in tendons, a corresponding equation is created. Comparison of calculation shows well agreement with the experimental results.  相似文献   
995.
Based on the optimal control theory and Lagrange interpolation an optimal design model of plane cascades of 3D blade in an arbitrary surface of revolution is established. Using wavelet theory to solve the model, and lots of numerical results are obtained. The results show that the wavelet method is more effective than the conventional methods.  相似文献   
996.
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   
997.
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   
998.
We present an adaptive algorithm for sequential diagnosis in the PMC model,which can directly identify a faulty processor without first identifying a fault-free processor.  相似文献   
999.
A raseach has been done on the possibility of producing nitriochumic acid fromweathered coal of Nantong,Sichuan,oxidised by nithic acid.The optimun reacting conditions,whichare found through the way of orthogonal experiment,are suggested as follows:concentration ofHON3 35%,rate of HON3 to coal 3.5,reacting take 15 min,and reaction temperature 369 K. Thecomposition of product is Wf 2. 91 %;Ag 14.06%;HAg 78.28%;Ng 1.62%.  相似文献   
1000.
The inherent fault tolerance of multilayer neural networks (MLNs) is due to thedistributed properties of information processing and information storage in an MLN , and the inher-ent fault-masking capability of every neuron. Also,the concept of inherent fault tolerance of MLNsis formalized, Finally, perceptrons and three-layer nets are shown inherently fault tolerant underreasonable statistical conditions,respectively.  相似文献   
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