Currently in the United States, periodic sensor recalibration is required for all safety-related sensors, typically occurring at every refueling outage, and it has emerged as a critical path item for shortening outage duration in some plants. Online monitoring can be employed to identify those sensors that require calibration, allowing for calibration of only those sensors that need it. International application of calibration monitoring has shown that sensors may operate for longer periods within calibration tolerances. This issue is expected to also be important as the United States looks to the next generation of reactor designs (such as small modular reactors and advanced concepts), given the anticipated longer refueling cycles, proposed advanced sensors, and digital instrumentation and control systems. The U.S. Nuclear Regulatory Commission (NRC) accepted the general concept of online monitoring for sensor calibration monitoring in 2000, but no U.S. plants have been granted the necessary license amendment to apply it. This report presents a state-of-the-art assessment of online calibration monitoring in the nuclear power industry, including sensors, calibration practice, and online monitoring algorithms. This assessment identifies key research needs and gaps that prohibit integration of the NRC-approved online calibration monitoring system in the U.S. nuclear industry. Several needs are identified, including an understanding of the impacts of sensor degradation on measurements for both conventional and emerging sensors; the quantification of uncertainty in online calibration assessment; determination of calibration acceptance criteria and quantification of the effect of acceptance criteria variability on system performance; and assessment of the feasibility of using virtual sensor estimates to replace identified faulty sensors in order to extend operation to the next convenient maintenance opportunity.

关键词：光机电；传感器；核电站；校准监视

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关键词：新《消法》；家电

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关键词：小家电；高端

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In this paper, we implemented discriminating system for various surround illuminants using photo sensor. To discriminate surround illuminants of display device we implemented discriminating system using photo sensor which has output Ye and Cy. Experimental results shows that we could discriminate surround illuminants effectively by using the output voltage ratio (Ye/Cy) of photo sensor in the varying luminous intensity of surround illuminants.

关键词：光机电；传感器；环绕照明；辨识系统

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关键词：变频；空调市场；产品策略

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中国中压配电网以架空线为主，多为小电流系统，单相接地故障占到电网故障总数的80％以上，但中国配网自动化系统基本上没有小电流接地故障定位功能，使配网自动化系统在提高可靠性的作用上大打折扣。给出一种小电流接地故障区段定位新方法，在线路上配置广域相量测量固定测点，获取小电流电网单相接地故障特征信息。基于测点相邻矩阵区段起始测点标识向量和故障路径标识向量概念，提出确定故障区间边界节点算法。物理模拟实验和挂网测试表明：该故障分区分段定位方法能够在线求解小电流接地故障段边界节点，缩小线路维护巡视范围。确定故障区间边界节点算法还可用于确定故障区相关负荷开关，为线路维护和馈线自动化提供依据。

关键词：配电自动化；架空线；小电流接地故障；区段定位；广域相量测量

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无单元伽辽金法（element．freeGalerkinmethod，EFGM）在电磁计算领域已经实现了初步应用。但是，面对结构复杂多介质场域问题时，介质间的交界条件需要额外处理以及建模过程繁琐等缺点，限制了该算法的发展。该文针对电机电磁场域的特点，提出在求解此类场域边值问题时，介质问交界条件近似满足，不必额外处理，并从理论上证明了论点在应用中具有可行性。相对于有限元法，文章分析了算法在复杂结构多介质电磁场应用中的优势，并将其引入到凸极同步电机空载磁场的计算中，结果验证了该文提出的观点是正确的。针对建模繁琐等问题，文章提出了可供参考的处理方案。

关键词：无单元伽辽金法；电机；电磁场；交界条件；数值计算

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纵向磁场对阳极活动的控制效果对于大电流真空电弧成功开断十分关键。采用建模仿真的方法，分析不同纵向磁场强度对阳极活动的影响。基于大电流真空电弧模型，仿真得到不同纵向磁场强度下输入阳极的能流密度分布，并以此作为阳极活动模型的边界条件，得到不同磁场强度下的阳极熔化、蒸发情况。仿真结果表明：对于工频电流（50Hz）电弧，阳极温度的最大值出现7ms时刻附近；随着纵向磁场的增大，阳极表面温度、饱和蒸汽压、阳极蒸汽流量都相应减小；随着纵向磁场的增大，熔化半径增大，但是熔化深度减小，改善了阳极的烧蚀情况。

关键词：真空电弧；阳极活动；纵向磁场；模型；仿真

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为了评价化学链重整制氢系统的性能，针对以CHa为燃料、以化学链技术（基于NiO／NiAl204氧载体）为核心的2种不同工艺重整制氢系统——自热化学链重整制氢系统（autothermal chemical loopingre for ming，CLR（a））#ll蒸汽重整化学链燃烧系统（chemicalloopingsteamreforming，CLR（s）），采用AspenPlus软件进行了过程模拟和热力学分析。以2种系统的产气率、冷煤气效率、CH。转化率等为评判指标，得到了各系统优化的反应条件，并分析了各操作参数（包括燃料／重整反应器温度和压力、CLR（a）~氧载体甲烷摩尔比和空气甲烷摩尔比、CLR（s）中水甲烷摩尔比和燃料甲烷份额）对系统性能的影响，最后对2种制氢系统进行了定量比较和分析。结果表明：2种化学链重整制氢系统具有相近的燃料发热量和CH4转化率（98％），但自热化学链重整制氢系统工艺更为简单，所需氧载体循环流量仅为蒸汽重整化学链燃烧制氢系统的1／3，从而可节约传输能量；而后者重整气中氢含量更高（74．14％对65．81％1，且具有更高的冷煤气效率（85．28％对71．19％）和产气率（4．05对2．97）。

关键词：过程模拟；化学链重整；甲烷；制氢；灵敏性分析

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提出两开关伪连续导电模式（pseudocontinuousconductionmode，PCCM）Buck-Boost功率因数校jE（powerfactorcorrection，PFC）变换器及其控制策略。利用两开关PCCMBuck．BoostPFC变换器电感惯性模态所提供的一个额外控制自由度，可实现单位功率因数控制，并明显改善传统单开关Buck-BoostPFC变换器、两开关连续导电模式（continuousconductionmode，CCM）Buck．BoostPFC变换器和两开关不连续导电模式（discontinuousconductionmode，DCM）Buck-BoostPFC变换器的性能。与两开关DCMBuck．BoostPFC变换器相比，两开关PCCMBuck．BoostPFC变换器减小了电感电流纹波。仿真与实验结果表明，两开关PCCMBuck-BoostPFC变换器的负载动态响应速度明显快于传统的两开关CCM和DCMBuck-BoostPFC变换器。

关键词：动态响应；低电感电流纹波；伪连续导电模式；功率因数校正；两开关Buck．Boost变换器

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