3 kW微波源传导电磁干扰测试及分析

微波源工作时内部的电磁干扰可以通过电源输入线耦合出来,干扰其他电力电子设备。研究三相输入电源线的传导干扰文献很多,但分离的共模（CM）和差模（DM）电流局限于相线之间,缺少对中线上干扰的分析。使用电流探头测试3 kW磁控管微波源输入线的传导干扰,利用矢量网络分析仪校准电流探头,从而获得150 kHz~30 MHz频带内相线和中线的传导干扰电流,并分离出CM电流与DM电流。通过对比DM电流和中线上干扰的频谱,分析了中线上传导干扰成分。测试数据表明,在150 kHz~8 MHz频带内差模干扰电流比共模干扰电流大10 dB以上;中线上的干扰与DM干扰幅值一致,表明中线上的干扰主要是差模成分。该干扰分布规律有助于提出有效的干扰抑制手段。     

矢量网络分析仪的时间门功能在吸波材料性能测试中的应用

在利用低频同轴反射法(LCR)进行材料吸波性能的测试过程中，经常会使用矢量网络分析仪的GATE功能来滤除干扰因素对测试结果的影响。本文通过对测试原理的阐述和不同吸波材料的测试结果的分析，说明了如何合理地设置矢量网络分析仪的GATE以及测试过程中应该注意的问题。     

一种EMI电流探头的校准方法

对电流探头进行校准，准确地将探头的转换因子定标，是保证EMC检测中多个项目质量的必要条件。在对EMI电流探头的现状进行介绍的基础上，提出了用微波网络分析仪校准电流探头的方法。该方法具有准确、便捷及自动描绘结果曲线的优点。     

表面电流探头的校准和应用

提出了在电磁兼容测量中应用的表面电流探头的校准方法、设计制作和实际应用。在这种方法中，平行板传输线被用来建立已知的、均匀的表面电流以确定表面电流探头的传输阻抗。文中提供了试验数据和图表，分析了测量的不确定性。最后，介绍了表面电流探头设计的关键特性以及在工程测量中的应用实例。     

用滤波器消除60Hz干扰

本文推荐的电路能滤去低频和低电平信号中的60Hz干扰。该滤波器具有40dB的干扰抑制功能(Q=0.75),并且对于来自单端5V电源的电流,其最大泄漏值为95μA。     

磁环的磁场分布测试研究

探讨了环型结构磁器件的磁场分布与器件的结构形状的关系，分析了理想霍尔传感器探头和有位置误差的实际霍尔传感器探头在环型结构磁器件磁场分布测试中对测试精度的影响。     

浅谈金属氧化锌避雷器带电监测和红外诊断

在由预防性试验向状态检修方式过渡的今天,避雷器安全运行故障诊断的重要性毋庸质疑。开展带电监测和红外诊断工作正是顺应了这一发展趋势。带电监测常用方法为全电流检测和阻性电流检测及红外诊断,但是无论那种技术手段的应用都有其局限性,全电流法在现场大量使用,但是当阻性电流发生变化时,总的泄漏电流变化不是很明显,而且灵敏度也较低;阻性电流的带电测试,灵活方便,但是容易受到相间电场的干扰,造成数据的偏差;而红外诊断的应用也受现场天气环境的影响。因此,在现场实际操作时,需要排除各种干扰和影响,找到真实的数据,才对避雷器的运行状况作出正确的判断分析,对隐患做到早发现、早处理,确保电网的安全运行。     

陶瓷相反应物加入量对等离子熔覆铁基涂层的组织影响

利用等离子弧喷焊技术,在Q235钢表面熔覆了铁基合金涂层以及加入陶瓷相反应物的铁基（Fe50）合金涂层。运用光学显微镜研究了各喷焊层的组织结构。     

对输电线路在运行中突然断线引发的思考——断线故障的防范与切除

断线故障属于纵向故障，是沿着电能传播的方向发生的故障，包括单相断线和两相（多相）断线。电力系统在非全相运行时，虽然不会引起大的短路电流和电压的急剧下降，但会产生大的负序和零序电流。负序电流使发电机绕组过热，零序电流对通信系统产生干扰，它们会引起电压、电流不对称并可能使某些继电保护误动作。     

制动器试验台的控制方法研究

针对制动器试验台上进行汽车制动性能模拟测试问题。本文采用电动机进行能量补偿实现惯量模拟的方法，通过控制电动机电流来补偿待模拟惯量存贮的动能，提出了一套随观测量实时调整电流的计算机辅助控制系统模型，并提出一些合理化建议。     

Does consumer‐firm affiliation matter? The impact of social distance on consumers’ moral judgments

When the leader of a firm commits a professional transgression, how would customers’ judgments of the transgressor's professional performance and immorality differ from those of noncustomers’? This research answers this question by investigating factors that explain the discrepancy in moral judgments between noncustomers and customers affiliated with the firm of a transgressing leader. Drawing on construal level theory, our two experimental studies consistently demonstrate that relative to high social distance (i.e., noncustomers), low social distance (i.e., customers) leads to more positive judgments of the transgressor's professional performance, but differences in the social distance do not directly lead to disparities in judgments of immorality. Social distance, however, affects both performance and immorality judgments when mediating mechanisms (conscious and nonconscious moral reasoning) are accounted for, such that low social distance indirectly influences customers to be more lenient in not only their performance judgments but also their immorality judgments. This research contributes to the topic of morality that permeates the current discourse on ethical business transgressions and, in particular, to an understanding of specific mechanisms that guide consumers’ moral judgments.     

X波段谐波混频频率合成器的设计

本文主要介绍利用谐波混频技术设计的X波段频率合成器。该频率合成器具有跳频速度快、输出频带宽、相噪低、体积小、重量轻等特点 ,同时没有倍频环节 ,降低了系统的设计难度 ,便于实现。     

一种无线异构网络中的分步协作基站分簇方法

为抑制小区间干扰提高系统性能,基于异构网络提出了一种分步基站分簇方法。该方法首先依据期望用户受到的除主服务基站之外的其余基站的信号干扰强度,确定待分簇基站集合;然后根据期望用户接收到待选集合中各个基站的信号强度,确定最终参与协作的基站集合。分步基站分簇方法通过缩小用户选择范围,同时综合考虑用户所在小区的信号强度和周围基站的干扰信号强度进行协作基站分簇。仿真结果表明:相对于现有功率最大法和阈值法,基于分步的基站分簇方法具有更高的用户端传输速率,更好地提升了系统性能。     

DS-CDMA系统窄带干扰的去除技术

在DS—CDMA中，频带内即使有一个窄带干扰存在，所有用户都会受影响，所以希望在DS—CDMA信号检波前除去窄带干扰。研究了利用干扰信号的窄带性和载波频率的事前信息的窄带干扰去除方案，以及对DS—CDMA信号的高功率窄带干扰的去除方法。     

Rewarding customers who keep a product: How reinforcement affects customers' product return decision in online retailing

A lenient product return policy represents the status quo of current return management practice in online retailing because it increases customers' order tendency. However, at the same time, many customers tend to return products under this policy, which incurs considerable costs for retailers. The present research introduces a keep reward (i.e., providing incentives to keep a product) as a new promotion strategy to improve the conventional lenient policy. Drawing on operant conditioning, the authors propose and test the reinforcing effect of a keep reward on customers' keep decision, compared to the conventional lenient policy. Results of a qualitative pilot study suggest that a keep reward is generally feasible in online retailing practice, especially in the low‐ to mid‐price segment and with rewards that are linked to future purchases. Two experimental studies verify the positive effect of a keep reward. Study 1 shows that it substantially increases keep intention compared to a conventional lenient policy. Study 2 shows that the effect on keep intention is moderated by customers' online shopping frequency, and this moderating effect is mediated by repurchase intention. In particular, the keep reward is most effective among frequent shoppers because they are more inclined to repurchase and thus, benefit from the reward. In summary, both studies support the keep reward as a valuable add‐on to the conventional lenient policy because order intention remains comparably high, while keep intention is higher. Theoretical implications and recommendations for online retailers on how to implement a keep reward in different industries are discussed.     

采用新型馈电结构的双频宽带导航天线设计

基于新馈电结构,设计了一款覆盖全球四大卫星导航系统的双频宽带贴片天线。采用了一种四分八馈电线路,以8个同轴馈电探针两两相连的方式将两路天线馈电信号合为一路,有效简化了馈电网络的复杂性,同时保证了天线辐射的增益、带宽和轴比性能。该双频辐射贴片单元采用正八边形层叠式结构设计,并在每个天线单元边缘对称添加两组矩形调谐单元,有效增加了天线辐射的波束带宽。该双频天线单元在高频1.482~1.617 GHz（波束带宽155 MHz）和低频1.191~1.252 GHz(波束带宽61 MHz）频段范围内,都能保证良好的辐射增益;高低频的3 dB轴比带宽为-130°~130°,具备良好的圆极化性能。经实物样机对比测试分析,实测结果与仿真结果基本吻合。     

Entrepreneurial capacities as antecedents of business performance in Brazilian firms

We investigate the relationship between entrepreneurial capacities and firm performance. More specifically, we investigate the effects of radical innovation and learning orientation on business performance. We test the effects of entrepreneurial orientation on learning orientation and radical innovation. The results suggest that radical product innovation and companies' orientation to learn have a positive effect on organizational performance. Additionally, we find that entrepreneurial orientation positively influences a firm's capability to learn and innovate. Our findings also show a direct effect of learning orientation on radical innovation, which means that companies with a higher proclivity to learn are more likely to create products and processes, representing a major departure from the state of current knowledge. Copyright © 2014 ASAC. Published by John Wiley & Sons, Ltd.     

Employee display of burnout in the service encounter and its impact on customer satisfaction

This study examines if employee display of burnout symptoms in service encounters has an impact on customer satisfaction. An experimental approach was used in which the employee's display of burnout (absent vs. present) and the service performance level (low vs. high) were the manipulated factors. The results show that employee display of burnout had a negative impact on customer satisfaction, that this effect was mediated by customers’ appraisals of the employee's emotional state, and that the effect was stronger under the condition of low service performance.     

The Role of Context Intensity and Working Memory Capacity in the Consumer's Processing of Brand Information in Entertainment Media

Despite the increasing use of entertainment media such as movies, sport telecasts, or video games as a way to get in touch with consumers, the understanding of the cognitive processing of brand information in these environments is still limited. This current research investigates the role of two moderating factors on brand information processing in entertainment media: Context intensity and working memory capacity. Context intensity relates to the perceived level of excitement in a communication environment, while working memory capacity indicates a consumer's ability to control his or her cognitive resources. The results of an experimental laboratory study reveal that context intensity negatively affects visual attention for brand information (i.e., intensity attention assumption), while working memory capacity has a positive influence on memory for brands (i.e., capacity memory assumption). These findings hold important implications for marketing management: First, managers should place brand information in situations where context intensity is rather low in order to facilitate the target group's visual attention. Second, the frequency and duration of brand information should be adjusted to the target group's ability to cognitively process such information.     

深空测控系统1 Hz低相噪频率合成技术

针对深空测控系统高精度测量对于信道附加相噪的要求,采用直接数字频率合成（DDS）正交调制方法设计频率综合器。通过巧妙的试验和外推方法,择优选取电压型鉴相器,在锁相环相噪模型的基础上,全面分析各部分相噪的贡献,综合设计环路带宽,有效控制附加相噪,实现低相噪频综器最理想的目标,即环路带内的相噪完全由参考决定,带外的相噪由压控振荡器（VCO）决定,并采用两源互比的方法完成1 Hz极低相位噪声的测试,测试结果为-73 dBc/Hz,与设计结果完全一致。该方法对于测控站极低相噪的设计具有一定参考价值。