以任意高维纠缠态为量子信道的受控隐形传态

目的是利用高维量子纠缠态为量子信道，讨论未知单粒子态的受控隐形传输问题。以三维量子纠缠态为信道，提出一个二维任意单粒子态的受控隐形传输协议。提出了以任意[d]-维量子纠缠态为量子信道，[t]-维任意单粒子态的隐形传输协议[(t相似文献   

Obtaining electrical characteristics of a PV module by FPGA based experimental system

Electrical characteristics of photovoltaic (PV) modules are significant for using in PV array and standalone applications. Therefore, when designing a PV system, these characteristics must be considered. Some methods are developed to achieve the electrical characteristics of PV modules and one of them is using a capacitor where it is connected to output of the PV module as a load. This method based on measuring the current and voltage of the capacitor during its charging. Thus, the electrical characteristics of the module can be obtained by using these measurements. In this article, Field Programmable Gate Array (FPGA) based method with using a capacitor is proposed to get electrical characteristics of the PV module. The method firstly simulated in Matlab-Simulink environment and promising results are obtained. Then, the method is performed by the FPGA based experimental system. At the same time, to prove experimental results, the electrical characteristics are derived by using an electronic load device. The experimental results show that the electrical characteristics can be accurately obtained by the proposed method.     

Numerical investigation of thermal and electrical management during hydrogen reversible solid-state storage using a novel heat exchanger based on thermoelectric modules

In order to reduce the costs generated by the hydrogen solid storage tank's accessories such as the heat exchanger, this work was carried out. It shows thermal and electrical investigations of transient hydrogen (H₂) solid storage in a tank filled with porous medium (LaNi₅) to activate a potential PEM automotive fuel cell. For this purpose, we use a novel heat exchanger with a heat sink combined with thermoelectric modules (TEMs). We realize a simulation that helps us verify if thermoelectric exchanger will be an alternative to the conventional ones. The main results are that a thermoelectric cooler and heater with 127 couples of semiconductors coupled with 19 fins heat sink could be used during the reversible hydrogen solid storage. Also, results show that we can avoid the water freezing at negative temperatures when using a conventional heat exchanger by using TEM during hydrogen absorption. Finally, during the endothermic desorption of the hydrogen, TEG use can avoid boiling water used in the heating system. Also, the hydrogen tank will be lighter and compact without fins and water tubes.     

基于垂直腔面发射激光器的高速率并行光发射模块

报道了关于并行光发射模块的设计与制作.优化设计、制作并测试了12信道并行光发射模块,单信道传输速率可达3Gbit/s.采用波长为850nm的垂直腔面发射激光器作光源,激光器与驱动电路芯片直接用金丝连接.输出光束直接耦合进入12信道的光纤阵列中.采用小型化可插拔封装结构以便在应用中实现热插拔.模块的测试结果表明,在8mA的工作电流下,测到3Gbit/s的清晰眼图.     

岩石断裂面的各向异性分形和多重分形研究

针对表面结构的分形各向异性和奇异性特征，对岩石断裂表面的多重分形性质进行了研究。提出了一种新的分形测量方法---投影覆盖法，直接测量断裂表面的多重分形维数Ｄ∈［２，３），并引入粗糙性概率度量表面不规则性。研究表明，断裂表面的多重分形谱可提供有关断裂机制的更丰富的信息，不同载荷条件和断裂模式下形成的岩石断裂面具有明显不同的多重分形谱函数特征。     

智能地雷爆炸成形弹丸着点偏差分析

智能地雷探测系统发现目标后,由母雷发射攻顶子弹,子弹通过敏感器识别目标并发射爆炸成形弹丸攻击目标。攻击过程时间短且动作复杂,因此有必要分析命中精度。通过研究运动学原理,建立以攻顶子弹、爆炸成形弹丸、攻击目标相对位置为依据的计算模型,计算了爆炸成形弹丸着点的偏差。计算表明:爆炸成形弹丸的命中精度与攻顶子弹的飞行状态、敏感器的性能和目标运动状态有关。研究结果为智能地雷总体设计提供了理论依据。     

基于投影积分的气-电耦合园区综合能源系统动态仿真方法

在充分考虑电力、燃气系统及其相互转化特性的基础上,建立了气-电耦合园区综合能源系统动态仿真模型,并根据动态过程的时间尺度对刚性系统进行划分;在此基础上,基于投影积分理论,提出一种适用于气-电耦合园区综合能源系统的高效率动态仿真方法,采用内部积分器以小步长的显式和隐式欧拉法交替求解来精细刻画快动态过程,采用外部积分器以可变大步长二阶牛顿插值高效求解慢动态过程,且在计算过程中能够有效计及故障扰动等事件的影响;对算法的数值精度进行分析。基于典型算例的算法测试表明,所提方法能够有效实现多场景下的气-电耦合系统快速稳定求解,在保证精度的前提下有效提升仿真效率。     

柔性直流输电功率模块过压保护误动原因分析及优化

针对鲁西柔性直流输电工程中换流器频繁发生功率模块过压保护误动的情况,提出一种防范功率模块过压保护误动的优化策略。分析功率模块在故障前后及旁路开关闭合前后的工作原理,剖析保护误动案例,阐述功率模块过压保护策略存在的电压测量采样异常导致换流器跳闸的风险,提出增加判断旁路开关是否发生拒动的防误判据。该优化策略在功率模块控制板中实现,可有效避免阀控层设备误判、误动作的风险。通过仿真验证了所提优化策略的有效性和可行性,目前该策略已在鲁西柔性直流输电工程中实际应用,取得了良好的效果。     

变电站直流电源系统现状与展望

变电站直流电源系统从20世纪90年代开始采用高频开关电源装置,距今已经20多年历史,虽然目前已经有发展较为成熟的成套系统如GZDW系列高频开关直流电源,但是仍存在谐波含量大、充电模块故障率高和智能化程度不高等问题。而且目前半导体器件已经发展到第三代的宽禁带半导体器件,变电站直流电源系统却仍停留于第一代硅器件的应用阶段,总体发展进程缓慢。针对变电站直流电源系统及其各模块现状进行研究,具体分析了诸如高性能充电模块、均流技术、谐波与功率因数校正等关键部分所存在的问题,并结合当今技术的潮流提出了对新一代变电站直流电源系统的展望。     

Solar stills for production of distilled water

Solar stills have been designed to produce water for use in teaching and research laboratories. Various designs and configurations have been constructed and tested over the past 10 years. The original double-surfaced cascade stills (stills A and B) were constructed in aluminium and were rather expensive. Later models termed Series D and E were of galvanised mild steel with stainless steel distillate drains and safety overflow drains. These galvanised steel units suffered from severe corrosion after a few years of operation. The latest design series F, is built in aluminium with stainless steel distillate drains and automatic feed valves. All of the stills produce very pure distilled water (conductance ～1.5 × 10^?6 Ω^?1 cm^?1; pH 6.8–7.4) at a cost which is below that of conventional electrically heated stills.