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991.
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993.
Ob ject recognition has many applications in human-machine interaction and multimedia retrieval. However, due to large intra-class variability and inter-class similarity, accurate recognition relying o... 相似文献
994.
In this paper, we present a new solving approach for a class of multi-leader–follower games. For the problem studied, we firstly propose a neural network model. Then, based on Lyapunov and LaSalle theories, we prove that the trajectory of the neural network model can converge to the equilibrium point, which corresponds to the Nash equilibrium of the problem studied. The numerical results show that the proposed neural network approach is feasible to the problem studied.
相似文献995.
996.
为了提高路径规划效率,提出一种改进的分层路网的路径规划算法。首先,城市路网进行分层处理,以经典A*算法为核心,在高层路网上使用改进机制,评估函数做相应调整,然后,对其权值设置上下限阈值,提高算法的搜索精度及搜索效率。实验结果表明,规划的路径并非Dijkstra算法的最短,但是改进的算法使快速路段所占比例达90%以上,实际运行最优。 相似文献
997.
基于Hyperworks的平衡轴支架拓扑优化设计 总被引:2,自引:0,他引:2
拓扑优化是一种根据载荷、约束及优化目标寻求结构材料最佳分配的优化方法,既可用于全新产品的概念设计,又可用于已有产品的改进设计;基于Hyperworks平台采用变密度法进行重卡平衡轴支架的拓扑优化设计,对优化后的重卡平衡轴支架进行有限元分析,将其应力分布、质量与原设计做比较;研究表明,经拓扑优化后的重卡平衡轴悬轴支架,应力大小大幅度减少,应力分布更加均匀,质量大幅度减少,实现了轻量化,为平衡轴支架结构的改进设计提供了重要的技术信息。 相似文献
998.
Though cryptography is being used more and more widely in reality, it seems that there exists no scheme or a concatenation of some existing schemes that could deal soundly with such practical situations as providing a clue, where the provider of the clue may want to reserve his beneficial rights while keeping his identity secret. To address this problem, inspired by the two notions of the ring signature and the authenticated encryption signature, we propose a new type of authenticated encryption scheme, which we call the ring authenticated encryption scheme, which can enable any member of a group of persons to provide a clue to some designated recipient wisely. 相似文献
999.
一种统一的资源预留策略 总被引:4,自引:0,他引:4
资源预留可以保证任务在开始执行时获得资源,而这在网格这样资源动态性很强的环境中是很可贵的,因而资源预留是网格任务调度中一种普遍采用的策略。当前资源预留的研究主要集中在计算资源预留的情况,文中提出了一个网格环境中资源预留的统一策略,该策略对其它资源的预留和计算资源的预留一起加以考虑,经过模拟验证,该策略能够很好地和我们先前设计的一种基于资源预留的任务映射算法结合起来,适用于网格的动态、异构性环境。 相似文献
1000.
Chengdong Li Jianqiang Yi Yisheng Lv Peiyong Duan 《IEEE/CAA Journal of Automatica Sinica》2019,6(6):1487-1498
In lots of data based prediction or modeling applications, uncertainties and/or noises in the observed data cannot be avoided. In such cases, it is more preferable and reasonable to provide linguistic (fuzzy) predicted results described by fuzzy memberships or fuzzy sets instead of the crisp estimates depicted by numbers. Linguistic dynamic system (LDS) provides a powerful tool for yielding linguistic (fuzzy) results. However, it is still difficult to construct LDS models from observed data. To solve this issue, this paper first presents a simplified LDS whose inputoutput mapping can be determined by closed-form formulas. Then, a hybrid learning method is proposed to construct the data-driven LDS model. The proposed hybrid learning method firstly generates fuzzy rules by the subtractive clustering method, then carries out further optimization of centers of the consequent triangular fuzzy sets in the fuzzy rules, and finally adopts multiobjective optimization algorithm to determine the left and right end-points of the consequent triangular fuzzy sets. The proposed approach is successfully applied to three real-world prediction applications which are: prediction of energy consumption of a building, forecasting of the traffic flow, and prediction of the wind speed. Simulation results show that the uncertainties in the data can be effectively captured by the linguistic (fuzzy) estimates. It can also be extended to some other prediction or modeling problems, in which observed data have high levels of uncertainties. 相似文献