Fluoroethylene Carbonate Additives to Render Uniform Li Deposits in Lithium Metal Batteries

Lithium (Li) metal has been considered as an important substitute for the graphite anode to further boost the energy density of Li‐ion batteries. However, Li dendrite growth during Li plating/stripping causes safety concern and poor lifespan of Li metal batteries (LMB). Herein, fluoroethylene carbonate (FEC) additives are used to form a LiF‐rich solid electrolyte interphase (SEI). The FEC‐induced SEI layer is compact and stable, and thus beneficial to obtain a uniform morphology of Li deposits. This uniform and dendrite‐free morphology renders a significantly improved Coulombic efficiency of 98% within 100 cycles in a Li | Cu half‐cell. When the FEC‐protected Li metal anode matches a high‐loading LiNi_0.5Co_0.2Mn_0.3O₂ (NMC) cathode (12 mg cm^?2), a high initial capacity of 154 mAh g^?1 (1.9 mAh cm^?2) at 180.0 mA g^?1 is obtained. This LMB with conversion‐type Li metal anode and intercalation‐type NMC cathode affords an emerging energy storage system to probe the energy chemistry of Li metal protection and demonstrates the material engineering of batteries with very high energy density.     

Policy Based Mobility &; Flow Management for IPv6 Heterogeneous Wireless Networks

We propose a dynamic mobility management framework for Internet Protocol version 6 (IPv6) and policy enforcement enabled heterogenous wireless networks. Policies and policy rules are defined depending on network infrastructure facilities, service agreements and negotiation results. Each traffic is coupled with an identifiable traffic flow while the heterogenous interface flow bindings are regulated by polices. The network selection, flow distribution, handovers and mobility procedures are flexible and we propose to improve the decision making via Multiple Attributes Decision Making (MADM). Techniques considered in the framework include the IPv6 based Network Mobility (NEMO), multihoming capability, transparent vertical handovers, horizontal handovers and dynamic policy enforcement matching process to improve the Quality of Service (QoS), Quality of Experience (QoE) and ubiquitous connectivity. A experiment testbed and simulation models have been constructed to verify the mobility framework performance in a heterogeneous WiFi, WiMax and UMTS hybrid environment.     

数字全息法测量透明物体变形的修正

采用数字全息可以测量透明物体的厚度变形场,但我们此前的研究忽略了应力导致的折射率变化,给测量带来了误差,本文对这个问题进行了讨论,修正了物光的相位变化与物体厚度变形间的关系。相较于修正前的公式,新增加了一个修正项,通过测量带孔有机玻璃试件在均布拉伸载荷作用下的厚度变形,并将测量结果与理论计算结果进行比较,发现用修正前的关系式得到的变形量偏大,而修正后的结果与理论值吻合很好,证明此修正是正确和必要的。     

Research on affine equivalence enumeration of the three families vectorial function

In recent years,Qu-Tan-Tan-Li function,Zha-Hu-Sun function and Tang-Carlet-Tang function have been proposed with differential uniformity 4 and many good cryptographic properties.the counting problem of affine equivalent to the three families cryptographic functions was investigated.By using some properties of finite fields,the upper and lower bound of the number of affine equivalent to the Zha-Hu-Sun function,and the upper bound of the number of affine equivalent to the Qu-Tan-Tan-Li function and Tang-Carlet-Tang function were computed,respectively.Moreover,a conjecture was given about the exact number of affine equivalent to the Zha-Hu-Sun function.Results show that there are at least$2^{53}{\left[{\displaystyle \prod _{i=1}^8(2^i-1)}\right]}^2$cryptographic functions of affine equivalent to the Zha-Hu-Sun function over finite field GF(2⁸),which can be chosen as S-boxes of block ciphers.     

Improved LEACH protocol algorithm for WSN based on energy balance and high efficiency

The improved energy-saving algorithm for the energy efficient and balanced protocol (LEACH-improved) was proposed.In the algorithm,the residual energy factor,the distance factor and the node density factor was added to improve the threshold formula.Moreover,in the various application scenarios of WSN,based on the different effects on the selection of cluster heads caused by the residual energy and geographical location,the weighting factor was introduced.Results of simulation experiments show that the improved algorithm can effectively reduce the network energy consumption and prolong the network lifetime.     

基于FRFT的一维距离像高速运动补偿

为提高高速运动目标的雷达识别性能,需要分析高速运动目标的回波模型,研究高速运动目标参数估计和一维距离像补偿方法.针对目标高速运动引起的回波脉冲压缩展宽,从而严重影响目标一维距离像成像质量的问题,建立了宽带线性调频信号的目标高速运动回波模型,分析了目标高速运动对高分辨一堆距离像的影响,提出了基于分数阶傅里叶变换参数估计的校正方法,消除目标高速运动对一维距离像的影响.通过引入逐级逼近搜索寻优算法,保证参数估计精度的同时提高计算的速度.仿真结果表明,文中提出的方法快速有效,且对噪声具有较好的鲁棒性.     

民机试飞空地一体化综合监控网络系统技术研究

以ARJ21适航审定试飞工程为背景,针对民机适航审定试飞的需求和测试特点,从优化系统架构和平衡系统性能等方面,对机载和地面各系统关键技术进行了分析。解决了新型多路网络化数据采集对机载和地面综合监控带来的一系列问题。提出了一套适合民机适航审定试飞的空地一体化综合监控网络系统解决方案。经过飞行试验证明,完全能够满足适航审定试飞空地一体化综合监控的要求,为今后大型飞机试飞测试及综合监控方法的研究提供了借鉴。     

基于GPS公交车限速报站系统设计

为实现公交车的自动报站功能,提出一种以C8051F040单片机和GPS卫星定位系统的设计方案。首先设置通过录音接口预存各站点具体位置的语音信息,当公交车在行驶时,能自动识别站点并完成语音报站功能,同时可设置公交车行驶的上限速度,当超过该速度值时,系统将完成语音报警提示。该系统定位准确,并可实现全天侯工作。     

直流固态功率控制器控制技术

直流固态功率控制器是智能开关装置,采用功率MOS管作为直流负载接通或断开直流电源的开关器件,能够实现过载、短路、超温等保护功能。通过DC-SSPC对直流负载进行远程控制,可随时获知负载的工作模式和运行状态,具备健康诊断和实时监控功能。主要研究了直流固态功率控制器工作原理及主要关键技术,并通过原理样机验证了直流固态功率控制器设计的可行性。     

基于STM32芯片的电能质量在线检测装置的设计与实现

为保证电能质量,需要对电能质量的各项指标进行全面的检测和分析,为改善电能质量提供决策依据。在参考电能质量国家标准的基础上,设计了一种以STM32芯片为核心的三相电能质量在线检测装置,给出了其硬件系统设计和基于小波变换算法的程序设计流程图,实现了对电能质量高精度的测量,比较于其他装置的设计方式更加简便但测量精度更高。在此将STM32芯片应用于电能质量检测装置中,降低了成本减小了功耗且测量精度提高。实验结果证明了该设计具有很好的的实用价值。