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991.
In this work, we propose a highly efficient binary tree‐based anti‐collision algorithm for radio frequency identification (RFID) tag identification. The proposed binary splitting modified dynamic tree (BS‐MDT) algorithm employs a binary splitting tree to achieve accurate tag estimation and a modified dynamic tree algorithm for rapid tag identification. We mathematically evaluate the performance of the BS‐MDT algorithm in terms of the system efficiency and the time system efficiency based on the ISO/IEC 18000‐6 Type B standard. The derived mathematical model is validated using computer simulations. Numerical results show that the proposed BS‐MDT algorithm can provide the system efficiency of 46% and time system efficiency of 74%, outperforming all other well‐performed algorithms.  相似文献   
992.
介绍了圆片级可靠性技术产生的背景,对其特点和作用作了详细的论述。测试内容上着重介绍了金属化完整性测试、氧化层完整性测试、连接完整性测试和热载流子注入测试,根据测试数据,对1.0μm工艺线单一失效机理的可靠性进行了评价,对不同测试结构的作用进行了说明。  相似文献   
993.
With the development of social media, television viewing is perceived no longer as an isolated activity. This study explores the underlying mechanism of the effects of social viewing discussion networks (i.e., bridging and bonding social viewing networks) on emotions (i.e., anger, fear, and enthusiasm), and moreover on opinion consolidation as well as opinion weakening in the context of the 2017 South Korean presidential debates. Overall, the main results are: a) Social viewing discussion networks influenced emotional states of social viewers, b) Emotions influenced attitude formation during social viewing, and c) Enthusiasm served as a catalyst that links bonding and bridging social viewing, and opinion consolidation. Implications and theoretical contributions are discussed.  相似文献   
994.
基于感知的视频编码方法综述   总被引:2,自引:0,他引:2  
基于感知的视频编码方法是目前视频编码的研究热点。该文综合论述了基于感知的视频编码方法,重点阐述了基于感知的3维视频编码方法。首先,对目前利用人类视觉系统中的亮度、对比敏感度、中心凹等视觉感知特性的单视点视频编码方法进行分析并指出其存在的问题。然后,对基于立体感兴趣区域和双目敏感度特性的3维视频感知编码方法进行了分析和论述。最后,就基于感知的视频编码方法的进一步发展提出了若干技术与研究方向的展望。  相似文献   
995.
云广平  郭万振 《电子科技》2011,24(2):115-118
研究了镀锌板无铬钝化工艺技术,用以取代传统的高毒性铬酸盐钝化处理.以钼酸盐为主要成分,对镀锌钢板钝化工艺技术进行了系统的研究.讨论了钝化温度、钝化处理时间、钝化液pH值等对钝化成膜及膜层耐蚀性的影响.通过醋酸铅点滴试验,电化学测试等方法对无铬钝化样品的耐蚀性进行了研究.实验结果表明,该无铬钝化膜具有较好的耐腐蚀性,但与...  相似文献   
996.
电信业务融合的发展趋势探讨   总被引:5,自引:0,他引:5  
电信业务融合与网络融合是存在关联的两个不同概念。一方面.网络融合不是业务融合的必须;另一方面,业务融合产生的降低业务承载成本的内在要求推动异构网络向同一方向发展。时当前多方面因素推动下的电信业务融合发展趋势进行了初步探对。  相似文献   
997.
汪凤玲  吴贇  支佳 《电子科技》2019,32(10):13-16
利用毫米波MIMO系统的稀疏特性,信道估计可以转化为稀疏信号重构的问题。解决毫米波MIMO稀疏信道估计问题时,传统的OMP方法需要信号的稀疏度作为先验信息,实际系统难以满足此需要。文中引入StOMP算法,根据信号已知的稀疏先验信息确定阈值,并结合动态的阈值调整,提出一种新的StOMP-D算法,实现了稀疏度自适应的毫米波MIMO信道估计。仿真结果表明,所提的方法与传统的LS方法比较,信道估计性能显著提高,并且与稀疏度已知的OMP方法性能十分接近,在稀疏度未知时有明显的优势。  相似文献   
998.
The fluorobenzotriazole (FTAZ)‐based copolymer donors are promising candidates for nonfullerene polymer solar cells (PSCs), but suffer from relatively low photovoltaic performance due to their unsuitable energy levels and unfavorable morphology. Herein, three polymer donors, L24 , L68 , and L810 , based on a chlorinated‐thienyl benzodithiophene (BDT‐2Cl) unit and FTAZ with different branched alkyl side chain, are synthesized. Incorporation of a chlorine (Cl) atom into the BDT unit is found to distinctly optimize the molecular planarity, energy levels, and improve the polymerization activity. Impressively, subtle side chain length of FTAZ realizes a dramatic improvement in all the device parameters, as revealed by the short‐current density (Jsc) improved from 7.41 to 20.76 mA cm?2, fill‐factor from 36.3 to 73.5%, and even the open‐circuit voltage (Voc) from 0.495 to 0.790 V. The best power conversion efficiency (PCE) of 12.1% is obtained from the L810‐based device, which is one of the highest values reported for FTAZ‐based PSCs so far. Notably, the corresponding external quantum efficiency curve keeps a very prominent value up to 80% from 500 to 800 nm. The notable performance is discovered from the reduced energy loss, improved molecular face‐on orientation, the down‐shifted energy levels, and optimized absorption coefficient regulated by side‐chain engineering.  相似文献   
999.
Low‐melting liquid metal is a hugely promising material for flexible conductive patterns due to its excellent conductivity and supercompliance, especially low‐cost and environmental liquid processing technology. However, the ever‐present fluidity characteristic greatly limits the stable shape and reliability of prepared liquid metal conductive electronics. Herein, a novel solidification strategy of liquid GaIn alloys by Ni doping and heat treatment is first reported, which can efficiently create a solid phase in the liquid metal and provide an effective solution for practical applications. Particularly, the liquid characteristic is preserved for conveniently fabricating different flexible electronic circuits, and then the solidification is carried out on prepared conductive patterns by heat treatment. The solidification mechanism is revealed by the interface chemical reaction between Ni and GaIn, creating the solid phase of intermetallic compound (Ga4Ni3 and InNi3) during heat treatment. Moreover, a biphasic GaInNi can be obtained by regulating the atomic ratio of gallium, indium, and nickel. As a result, the obtained GaInNi possesses extremely low sheet resistance (15 ± 4.5 to 135 ± 2.5 mΩ sq?1) and the variation of ΔR/R0 exhibits low level (0–2) when strained up to 100%, which offers a promising strategy to prepare stretchable and reliable liquid metal electronics.  相似文献   
1000.
For future wireless communication systems, Power Domain Non-Orthogonal Multiple Access (PD-NOMA) using an advanced receiver has been considered as a promising radio access technology candidate. Power allocation plays an important role in the PD-NOMA system because it considerably affects the total throughput and Geometric Mean User Throughput (GMUT) performance. However, most existing studies have not completely accounted for the computational complexity of the power allocation process when the User Terminals (UTs) move in a slow fading channel environment. To resolve such problems, a power allocation method is proposed to considerably reduce the search space of a Full Search Power (FSP) allocation algorithm. The initial power reallocation coefficients will be set to start with former optimal values by the proposed Lemma before searching for optimal power reallocation coefficients based on total throughput performance. Step size and correction granularity will be adjusted within a much narrower power search range while invalid power combinations may be reasonably discarded during the search process. The simulation results show that the proposed power reallocation scheme can greatly reduce computational complexity while the total throughput and GMUT performance loss are not greater than 1.5% compared with the FSP algorithm.  相似文献   
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