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A full distribution CNC system based on SERCOS bus is studied in accordance with the limitations of traditional PC-based motion card. The conventional PC-based motion control card is dispersed into several autonomous intelligent servo-control units with the function of servo driver. The autonomous intelligent servocontrol units realize the loop control of position, velocity and current. Interpolation computation is completed in PC and the computational results are transferred to every autonomous intelligent servo-control unit by high speed SERCOS bus. Software or hardware synchronization technology is used to ensure all servomotors are successive and synchronously running. The communication and synchronization technology of SERCOS are also researched and the autonomous intelligent servo-control card is developed byself. Finally, the experiment of circle contour process on a prototype system proves the feasibility. 相似文献
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Most inventory researches assume that production level can fluctuate arbitrarily. However, large fluctuation of the production
level in many firms may be much costly. This paper addresses the coordinating pricing and inventory control problem in a bounded
production system with uncertain yield, in which the production level is constrained between a maximum and minimum level in
each period and the price can be adjusted dynamically. We show that the optimal policy is the interval base-stock-list-price
policy. Also, we study the impact of the production bounds and uncertainty of the yield on the production system. Numerical
experiments are also performed to study the impact of parameters on the system. 相似文献
36.
The reverse construction and analysis of the networks of molecular interactions are essential for understanding their functions
within cells. In this paper, a logic network model is constructed to investigate the complicated regulation mechanism of shoot
genes of Arabidopsis Thaliana in response to stimuli. The dynamics of the complicated logic network is analyzed, discussed,
and simulated. The simulation results show that the logic network of the active genes of shoot eventually evolves into eleven
attractors under the stimuli, including five 1-periodic and six 2-periodic attractors. Our work provides valuable reference
and guidance for biologists to understand and explain Arabidopsis’ response to external stimuli by experiments. 相似文献
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在卫星多目标跟踪的背景下,针对传感器网络的协同问题,首次建立了完整的基于移动动态联盟的多目标协同跟踪模型,并针对协同过程中的移动动态联盟形成问题,提出了基于博弈论的联盟形成算法。该协同模型在跟踪多目标时利用移动动态联盟来交换并协调节点间的信息,使节点的行为一致,具有分布式和自组织的特点。仿真实验验证了该协同模型应用在传感器网络多目标跟踪中的有效性。Abstract: As to the collaborative technique in sensor network,an integrated multi-target collaborative tracking model was constructed based on mobile dynamic coalition under the background of multi-satellite tracking.Then as to the mobile dynamic coalition formation,a coalition formation method was proposed based on game theory.Using mobile dynamic coalition,this collaborative model exchanged and coordinated the information of nodes to accord their action.So it is distributive and self-organizing.Simulation results validate the effectiveness of collaborative model in sensor network tracking multi-target. 相似文献
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在网络仿真中,链路模型的精确性对仿真结果的真实性有着重要影响。基于在无线传感器网络实验中观察到的链路的核心特殊性质——不等向连通性,提出了一个真实的链路仿真模型RLINK.通过对不等向连通性的三个因素进行分析建模,即由遮蔽效应引起的路径衰减的差异、节点硬件的校准差异和天线的方向性差异,该模型实现了无线传感器网络链路的精确模拟。以链路不对称性的累积分布和算数平均值为指标,对比实验和仿真中获得的有关链路特性的统计数据,两者的一致性验证了RLINK的精确性。Abstract: In network simulation,the accuracy of the link model has significant impacts on the credibility of the simulation results.Based on the core feature of links obtained from the recent empirical studies,a realistic link model,named RLINK,was proposed for a more credible simulation of wireless sensor networks (WSNs).RLINK captured the essential non-isotropic feature of the wireless links in WSNs by modeling three main causes: variance of path loss due to shadowing effect,difference in hardware calibration and radio directionality.The accuracy of RLINK model was verified by the high agreement of the statistical results obtained from simulations with those obtained from experiments,in terms of cumulative distribution of link asymmetry and arithmetic average of link asymmetry. 相似文献
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China's aerospace enterprises carry on the multinational operation and participate in the international competition and the international division of labor and cooperation positively. This article first analyzs China aerospace enterprises' binary multinational business control objective and constructes its model. Then the article analyzes the tangible and intangible control mechanism of China aerospace enterprises' binary multinational operation respectively. Finally, the article constructs the model of China aerospace enterprises' binary multinational operation mechanisms. 相似文献