采用自适应信号恢复算法的非接触式心率检测

目的 心率是反映人体心血管状况和心理状态的重要生理参数。最近的研究表明,光电容积成像技术可以在不接触人体的情况下,利用消费级的摄像机捕获面部表皮颜色的变化进而估计心率。然而,在实际环境中,面部运动带来的干扰会导致心率检测的准确性下降。近年来,国内外学者已经提出了一些方法来去除运动噪声,但是效果均不理想。为了解决上述问题,提出一种可以抗面部运动干扰的新方法。方法 首先检测和跟踪受试者的脸部。然后将脸部区域分块,并提取各块的色度特征建立原始血液容积脉冲矩阵,利用自适应信号恢复算法从原始血液容积脉冲矩阵中分离出低秩矩阵并构建期望血液容积脉冲信号。最后通过功率谱密度估计心率。结果 在环境光作为光源的条件下,利用网络摄像头采集30名受试者的人脸视频进行实验分析。结果显示,提出的方法测得的心率与参考值具有很强的相关性：在静态场景中皮尔森相关系数r=0.990 2,在动态场景中r=0.960 5。并且与最新方法相比,动态场景中的误差率降低了53.90%,相关性提高了7.46%。此外,在10 min的心率检测实验中,方法的测量值与参考值保持着良好的一致性。结论 本文方法优于现有的非接触式心率检测技术,能有效地消除面部运动带来的干扰,长期稳定地检测心率。     

A tradeoff between unit capacity and average production cost in spinning reserve optimization

In power systems the spinning reserve (SR) amount can be determined by deterministic or probabilistic techniques. Probabilistic techniques draw more attention since they can consider the economics and the stochastic nature of system behavior and component failures. In probabilistic techniques, the tradeoff between cost and reliability directly affects the SR deployment and it has been extensively analyzed. However, there is another tradeoff which reflects the compromise between the unit capacity and average production cost in the SR optimization problem. This tradeoff impacts the solution accuracy to a certain extent and influences the complexity of the model, and it has not been explicitly analyzed before. In this paper, a new SR optimization method is proposed in which the tradeoff between unit capacity and average production cost is well respected. The proposed method strikes a good balance between solution accuracy and computation efficiency and can obtain better results within a desirable run time compared with those of the previous methods. Besides, the proposed method can also be used to improve the solution of the reserve constrained unit commitment problem. It can lower the total cost by just redistributing the MW dispatch even when the SSR is fixed. The efficiency and validity of the proposed method are verified using the IEEE reliability test system.     

空调器固体继电器的选用

介绍了空调器固体继电器的基本特性,以及应用选型、布局和在应用中应采取的保护措施,以实现固体继电器在使用中的可靠性。     

内蒙古地区绿豆品种遗传多样性SSR分析及DNA指纹图谱构建

目的:分析内蒙古地区绿豆品种的遗传多样性并构建其DNA指纹图谱,为探明绿豆种质资源遗传背景及真伪鉴定提供科学依据。方法:以内蒙古地区92份绿豆品种为模板,利用筛选得到的10对多态性丰富的简单重复序列(simple sequence repeat,SSR)引物对其进行遗传多样性分析及DNA指纹图谱构建。结果:10对SSR引物共检测到58个等位基因,每对引物检测到3~10个不等;不同引物揭示的多态信息含量变幅介于0.371 4~0.773 7,平均为0.52。92份绿豆种质的遗传相似系数变幅介于0.033 4~1.000 0之间,平均为0.46。非加权组平均法聚类分析结果显示,在遗传相似系数为0.294 4时,可将92份绿豆种质分为两大类群。构建了92份绿豆品种的SSR指纹图谱及分子身份证,除个别品种外,大部分具有唯一性,可用于品种鉴定。结论:内蒙古地区绿豆种质资源的遗传多样性相对较丰富,但存在一定程度的近交现象,有待进一步加强引进基因资源,创新绿豆育种材料;构建绿豆SSR指纹图谱和分子身份证,对绿豆品种真伪鉴定、身份识别、溯源管理及原产地保护具有重要意义。     

青藏高原露天矿山高陡边坡稳定性监控实践

边坡稳定性监测雷达SSR系统是世界先进的亚毫米级精度的持续实时监测技术,也是高精度、长距离边坡稳定性监测设备。该文以西藏华泰龙矿业开发有限公司甲玛露天矿区边坡稳定性监控实践为例,通过引进国外雷达SSR系统,并以该系统为主创建了露天矿山高陡边坡稳定性监测系统,达到了实时监控和预测边坡失稳的目的。对同类露天矿山安全生产管理水平的提高,具有重要的推广价值和广阔的应用前景。     

RAPD and SSR Polymorphisms in Mutant Lines of Transgenic Wheat Mediated by Low Energy Ion Beam

Two types of markers-random amplified polymorphic DNA （RAPD） and simple sequence repeat DNA （SSR）-have been used to characterize the genetic diversity among nine mutant lines of transgenic wheat intermediated by low energy ion beam and their four receptor cultivars. The objectives of this study were to analyze RAPD-based and SSR-based genetic variance among transgenic wheat lines and with their receptors, and to find specific genetic markers of special traits of transgenic wheat lines. 170 RAPD primers were amplified to 733 fragments in all the experimental materials. There were 121 polymorphic fragments out of the 733 fragments with a ratio of polymorphic fragments of 16.5%. 29 SSR primer pairs were amplified to 83 fragments in all the experiment materials. There were 57 polymorphic fragments out of the 83 fragments with a ratio of polymorphic fragments of 68.7%. The dendrograms were prepared based on a genetic distance matrix using the UPGMA （Unweighted Pair-group Method with Arithmetic averaging） algorithm, which corresponded well to the results of the wheat pedigree analysis and separated the 13 genotypes into four groups. Association analysis between RAPD and SSR markers with the special traits of transgenic wheat mutant lines discovered that three RAPD markers, sl, opt- 16, and f14, were significantly associated with the muticate trait, while three SSR markers, Rht8 （Xgwm261）, Rht-Blb, and Rht-Dlb, highly associated with the dwarf trait. These markers will be useful for marker-assistant breeding and can be used as candidate markers for further gene mapping and cloning.     

NGH次同步谐振阻尼方案及其改进措施的研究

针对串联补偿系统次同步谐振的抑制及防止措施,对NGH次同步谐振阻尼方案作了详细的理论分析和仿真研究,并在此基础上对原NGH方案作进一步的改进,提出了带有次同步谐振检测和预触发功能的NGH方案。通过具体算例的仿真分析说明,NGH次同步谐振阻尼方案对提高暂态转矩稳定和有次同步谐振问题系统的稳定性是非常有效的。采用改进方案后,NGH控制在次同步谐振发生时能自动投入,比原方案更迅速有效地抑制振荡,在次同步谐振基本抑制后又能自动平滑地退出。     

含TCSC的电力系统次同步谐振的复转矩系数分析法

经推理证明,对于采用固定串联电容补偿的电力系统,如果对发电机转子角度施加一微小正弦扰动,则按系统线性化方程求得的电磁转矩稳态增量的正弦和余弦分量的幅值分别与电气弹性系数和电气阻尼系数成正比,从而提出了一种计算复转矩系数的微小扰动稳态响应算法。然后将这种算法推广到采用晶闸管控制的串联电容补偿电力系统的次同步谐振分析中,给出了具体的计算公式和步骤。采用IEEE典型系统进行计算,所得结果与采用EMTP时域仿真的结果相吻合。     

超高压输电系统可控串补(TCSC)动态模拟

以东北电网拟建的５００ｋＶ伊敏－冯屯交流输电系统所需可近串联补偿电容装置（ＴＣＳＣ）为研究目标,建立了包括ＴＣＳＣ的整个系统的动态模拟装置。在此基础上,进行了ＴＣＳＣ整体动模装置的基本运行方式,潮流控制以及暂态响应的试验,所得结果与理论分析一致,此外,单一回线运行时,在接近谐振点的某一补偿度上,观察到了次同步谐振（ＳＳＲ）现象,并对此现象进行了分析。     

大规模双馈风电场次同步谐振的分析与抑制

已有的运行经验表明,风电场接入含有固定串补的系统时,存在诱发次同步谐振(SSR)的风险.因此,有必要对风电场发生SSR现象的机理做深入分析,以便提出相应的抑制措施.文中首先根据国内某地区风电场的实际参数建立了应用于SSR分析的等值模型,通过仿真呈现了该模型发生SSR的情形;然后,利用特征值法分析了风速、并网风力发电机台数以及双馈感应发电机(DFIG)控制参数等对系统SSR频率和阻尼特性的影响;并进一步推导了等值模型用于SSR分析的等效电路,详细分析了风速、发电机台数和DFIG控制参数等影响SSR特性的机理;综合所有的分析指出,风电场的SSR现象与轴系扭振无关,是一种特殊的电气谐振.最后,提出了抑制风电场SSR的方案,并通过仿真和特征值分析进行了验证.