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Mobile Networks and Applications - Thompson sampling is one of the most effective strategies to balance exploration-exploitation trade-off. It has been applied in a variety of domains and achieved... 相似文献
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数据库管理信息系统是一个主要以人为主导的,利用电子计算机硬件、通过他软网络通讯设施和其他一些办公室设备集合起来进行信息收集、信息传授、价格、信息储存以及信息的更新和维护,要以企业战略优化出发,为了提高经济效益和企业效率为主要目的的,并且是支持企业高层决策、中层控制以及基层运作的一个集成化的人机系统。 相似文献
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The prohibitive - exponential in the number of users - computational complexity of the maximum-likelihood multiuser detector for direct-sequence code-division multiple-access communications has fueled an extensive research effort for the development of low-complexity multiuser detection alternatives. We show that we can efficiently and effectively approach the error rate performance of the optimum multiuser detector as follows. We utilize a multiuser zero-forcing or minimum mean-square error (MMSE) linear filter as a preprocessor and we establish that the output magnitudes, when properly scaled, provide a reliability measure for each user bit decision. Then, we prepare an ordered, reliability-based error search sequence of length linear in the number of users; it returns the most likely user bit vector among all visited options. Numerical and simulation studies for moderately loaded systems that permit exact implementation of the optimum detector indicate that the error rate performance of the optimum and the proposed detector are nearly indistinguishable over the whole predetection. signal-to-noise ratio range of practical interest. Similar studies for higher user loads (that prohibit comparisons with the optimum detector) demonstrate error rate performance gains of orders of magnitude in comparison with straight decorrelating or MMSE multiuser detection. 相似文献
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Bo Qiao Di Zhou Zhenyu Dai Weikang Zhao Qiming Yang Yanan Xu Xiangjie Li Jun Wu Shuquan Guo Dianming Jiang 《Advanced functional materials》2019,29(22)
Bone plates have been applied to fix fractures for over a hundred years. Metal plates are the gold standard. However, an increasing number of clinical practices and animal experiments have shown that metal plates have had incidents of failure due to their rigid fixation and long‐term complications. Degradable composites present the advantages of a lower elastic modulus and absorbable properties but are unsuitable for load‐bearing applications. Nondegradable bone plates composed of a nanohydroxyapatite/polyamide 66/glass fiber (n‐HA/PA66/GF) composite are prepared, which have enough strength and a low elastic modulus for an internal fixation device. To better assess its function as a bone plate, animal experiments are conducted using a canine load‐bearing femur fracture model. The results show that the n‐HA/PA66/GF plate can fix fractures effectively. Gross observation, radiographic films, and histological analysis all show that the n‐HA/PA66/GF plate leads to a secondary (indirect) union with obvious callus formation, whereas the titanium plate leads to primary (direct) union due to rigid fixation. Furthermore, the histological results reveal that new bone grows at the interface and that the n‐HA/PA66/GF plate can integrate with native bone tissue. Consequently, the n‐HA/PA66/GF composite shows good potential as a bone plate to fix loading‐bearing bone fractures. 相似文献
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Optimization algorithms are proposed to maximize the desirable properties while simultaneously minimizing the undesirable characteristics. Particle Swarm Optimization (PSO) is a famous optimization algorithm, and it has undergone many variants since its inception in 1995. Though different topologies and relations among particles are used in some state-of-the-art PSO variants, the overall performance on high dimensional multimodal optimization problem is still not very good. In this paper, we present a new memetic optimization algorithm, named Monkey King Evolutionary (MKE) algorithm, and give a comparative view of the PSO variants, including the canonical PSO, Inertia Weighted PSO, Constriction Coefficients PSO, Fully-Informed Particle Sawrm, Cooperative PSO, Comprehensive Learning PSO and some variants proposed in recent years, such as Dynamic Neighborhood Learning PSO, Social Learning Particle Swarm Optimization etc. The proposed MKE algorithm is a further work of ebb-tide-fish algorithm and what’s more it performs very well not only on unimodal benchmark functions but also on multimodal ones on high dimensions. Comparison results under CEC2013 test suite for real parameter optimization show that the proposed MKE algorithm outperforms state-of-the-art PSO variants significantly. An application of the vehicle navigation optimization is also discussed in the paper, and the conducted experiment shows that the proposed approach to path navigation optimization saves travel time of real-time traffic navigation in a micro-scope traffic networks. 相似文献
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针对税控领域中发票数据的防伪问题,设计了一种基于FPGA的税控算法加密卡。该加密卡以FPGA为控制核心,通过嵌入式PCI-IP核实现了PCI总线的接口逻辑,并利用状态机控制税控密码算法芯片高效运行,另外,设计的DMA控制器实现了数据的快速传输。通过仿真验证,该设备应用于税控行业,可保证发票数据的正确加密和可靠存储。 相似文献
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Hard–Soft Composite Carbon as a Long‐Cycling and High‐Rate Anode for Potassium‐Ion Batteries 下载免费PDF全文
Zelang Jian Sooyeon Hwang Zhifei Li Alexandre S. Hernandez Xingfeng Wang Zhenyu Xing Dong Su Xiulei Ji 《Advanced functional materials》2017,27(26)
There exist tremendous needs for sustainable storage solutions for intermittent renewable energy sources, such as solar and wind energy. Thus, systems based on Earth‐abundant elements deserve much attention. Potassium‐ion batteries represent a promising candidate because of the abundance of potassium resources. As for the choices of anodes, graphite exhibits encouraging potassium‐ion storage properties; however, it suffers limited rate capability and poor cycling stability. Here, nongraphitic carbons as K‐ion anodes with sodium carboxymethyl cellulose as the binder are systematically investigated. Compared to hard carbon and soft carbon, a hard–soft composite carbon with 20 wt% soft carbon distributed in the matrix phase of hard carbon microspheres exhibits highly amenable performance: high capacity, high rate capability, and very stable long‐term cycling. In contrast, pure hard carbon suffers limited rate capability, while the capacity of pure soft carbon fades more rapidly. 相似文献