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51.
针对操作人员难以在有限的光学运动捕捉设备捕捉范围内自由运动的问题,开展了协同虚拟维修过程中的虚拟人体维修操作控制研究。基于光学运动捕捉设备对操作人员的下肢动作进行捕捉,根据实时识别结果控制虚拟人体进行大范围运动。针对维修操作过程中的虚拟人体手部运动控制,分析了虚拟人体的手部交互过程,提出了一种基于动态贝叶斯网络的维修操作智能辅助方法。以某液压缸协同式虚拟维修操作仿真平台为例验证了方法的有效性。该方法实现了对虚拟人体维修操作过程的有效控制,具有实时性好、交互性与感知性强等优点。 相似文献
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The discrete-time model of plague is deduced by zero-order holder based on the continuoustime model. Due to the existence of stochastic disturbances, the stochastic model is given corresponding to the discrete-time model. The state estimation and noise reduction of the stochastic model are achieved by designing Kalman filter. Nuclear norm minimization is to structure the low-rank matrix approximation instead of the singular value decomposition in the process of subspace system identification. According to the plague data from the World Health Organization, the system matrices and noise intensity of the model are identified. Simulations are carried out to show the higher approximation capability of the proposed method. 相似文献
56.
Facing with increasing competition, many ports are taking innovative approaches to improve productivity and profits. Among a variety of methods, introducing external terminal operators(ETOs) while the port acts as a landlord to collect "rents" from those operators for conducting terminal activities inside the port is regarded as an effective way and is commonly observed in practices.This paper analyzes the decisions of two competing ports about whether to introduce their respective ETOs using a three-stage non-cooperative game model when there already exists a port's self-operation terminal operator(STO). At the first stage, the two ports simultaneously decide whether to introduce an ETO. If a port decided to introduce an ETO, at the second stage, it will further decide the unit fee to charge from the ETO. At the third stage, the two ports and the introduced ETO(s) simultaneously decide their respective profit-maximizing output levels. The findings indicate the equilibrium is both ports will introduce their respective ETOs, but when the ports and ETOs are substitutable in the sense of having the same level of productivity, the equilibrium solution is only one port should introduce an ETO. And simulation results show that even if one of ETOs is inefficient this still hold true. 相似文献
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Since 2010, Chinese government has introduced a series of administrative policies to limit speculation in the housing market to stabilize price fluctuations and keep the housing market in a healthy state of development. In order to investigate whether administrative policy can play its due role, this paper constructs a comprehensive bottom-up housing market heterogeneous households multiagent model(HHMAM) to undertake research on the differentiated effect of administrative policy in different cities. The empirical studies find that: 1) Administrative policy that increases interest rates will cause housing prices to continue to decline in the long term, but they will resume a rising trend after reaching the lowest point; 2) If the government cancels a property-purchasing limitation, housing prices will continue to rise; and 3) investors tend to invest in 1~(st)-tier cities due to the high demand and greater likelihood of appreciation in these cities. 相似文献
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Journal of Systems Science and Complexity - Nonlinear feedback shift registers (NFSRs) are widely used as building blocks in the design of stream ciphers. Let NFSR(f) be an NFSR with the... 相似文献
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In social networks, the structural balance is a state of a group of individuals(nodes) with established mutual relationships(connection relationships) between them. It is easy to see that a social network can be described by a complex dynamical network model composed of the nodes subsystem(NS) and the connection relationships subsystem(CS), where the two subsystems are usually coupled with each other. It implies that the dynamic changes of nodes' states may cause the structural balance in CS. However, few papers have discussed the relationship between the structural balance and the specific dynamic changes of the nodes' states. This paper proposes a model of complex dynamical networks, and mainly focuses on the dynamic changes of states in NS which can lead to the structural balance in CS. It is proved that if each state in NS is doing a specific dynamic motion via the controller with the parameter adaptive law, then the CS can track a given structural balance matrix via the effective coupling and the structural balance can be achieved. Such a result can be regarded as an explanation of the relationship between the structural balance and the specific dynamic changes of the nodes' states. Finally, the simulations verify the effectiveness of the proposed method. 相似文献
60.
Robust fuzzy filterings for a class of nonlinear stochastic systems with infinite Markov jump are explored based on T-S fuzzy model approach in this paper. First of all, the exponentially mean square stable filter with a prescribed H∞ performance is designed via linear matrix inequalities(LMIs). Secondly, H2/H∞ fuzzy filtering is solved in terms of LMIs by minimizing the estimation error energy under the worst case fuzzy disturbance. The corresponding fuzzy filter parameters can be received by convex optimization algorithms. And lastly, two illustrative examples are performed to manifest the validity of the proposed methods. 相似文献