EMI滤波器的设计

文章从建立EMI滤波器的共模、差模噪声源等效电路及电路模型入手,进而探讨了EMI滤波器的设计方法及其在实际应用的结构和结构参数的选择问题。     

SEM图像分形维数的影响因素研究

以玻璃光纤、碳纤维纸和两种机加工表面样本的扫描电子显微镜图像为对象,运用盒维法研究了不同的放大倍数和采集过程中受到的噪声干扰对分形维数的影响.研究结果表明,随着放大倍数增大或随着椒盐噪声密度和高斯随机噪声方差的减小,分形维数下降.放大倍数和噪声对分形维数都有较大影响.在扫描电子显微镜图像分形维数的计算中,可以依据试样的结构特征选择合适的放大倍数,进行去噪处理后再计算图像的分形维数.     

加强大学生心理健康指导的实践

大学生出现的心理问题日趋凸显,应充分认识加强心理健康指导的重要性,建立预警制度,加强心理指导和危机干预,发挥多方面作用,引导学生健康成长。     

S-CDMA技术在HFC网络上行信道中的分析应用

在基于CATV的HFC双向网络中,S-CDMA的同步处理技术可以最大限度地克服上行信道中的噪声干扰,提高信道的利用率,确保数据传输的可靠性。     

The Announcement Effect of an Airport Expansion on Housing Prices

The purpose of this study is to examine the influence of the announcement of a new airport hub on housing prices near the airport. While numerous studies of airport noise have found that high noise levels reduce property values, few have been able to measure the announcement effect on values. The results indicate that after controlling to extraneous influences, housing property prices in a 2.5 mile band from the Greensboro/High Point/Winston Salem metropolitan airport declined approximately 9.2% in the post-announcement period. In the next 1.5-mile band, house prices declined approximately 5.7% in the post-announcement period.     

A Tutorial on Palm Distributions for Spatial Point Processes

This tutorial provides an introduction to Palm distributions for spatial point processes. Initially, in the context of finite point processes, we give an explicit definition of Palm distributions in terms of their density functions. Then we review Palm distributions in the general case. Finally, we discuss some examples of Palm distributions for specific models and some applications.     

一种改进的CPFSK信号频率估计方法

针对突发信号解调中多普勒频偏大的问题，提出了一种改进的连续相位移频键控信号(CPFSK)频率估计方法。首先接收信号平方运算使信号的调制指数加倍，再通过一次离散傅里叶变换(DFT)，用搜索信号平方谱谱峰的方法实现突发信号频率估计。仿真实验表明，在低信噪比条件下，该算法的频率估计精度比经典的相位差频率估计算法提高了20%；该算法与广泛用于高动态突发信号的频率插值估计算法相比，同道干扰信道下信干比改善可达4 dB，DFT长度缩短约1/3。     

基于多维频谱地图的干扰规避

针对复杂电磁环境下卫星移动通信系统可靠通信需求，利用频谱地图多维数据呈现优势，提出了基于多维频谱地图的干扰规避方法。通过建立卫星移动通信系统波束、时隙、子频带、干扰强度等多维信息关联的频谱地图，利用数据挖掘方法对频谱可用情况进行预测，基于预测结果及用户QoS(Quality of Service)需求生成干扰规避策略，通过星地联合频谱资源调配实现系统干扰规避。该方法为卫星移动通信系统干扰规避提供了一种全新的思路，可提升卫星移动通信系统干扰防护能力。     

A train of thought in product experientiality: Working memory,distraction, and inconsistencies in cue order effects

The sequence of informational cues and the level of distraction have an impact on the judgment of a product’s quality and preference. Two quasi-experimental studies (N_total = 340) investigate the influence of the force behind the processing of these cues – working memory (WM). Previous research found that, in the presence of a distractor, high WM individuals are more able to recall the initial cue, and thus derive their product judgment from the initial strong cue. Study 1 contradicts these findings and raises important methodological questions regarding the conceptualization of strong and weak cues. Specifically, commonly accepted strong cues (e.g., product reputation) might not influence consumers as expected. Additionally, in a sequence of product evaluation with high vs. low degree of experientiality, study 2 reveals that consumers tend to show a primacy effect that is stronger for higher levels of WM capacity. Moreover, in a sequence of assessing low vs. high degree of experientiality products, consumers reveal stronger recency effects, thus showing that WM reinforces this recency effect. Our findings have important implications for marketers by suggesting that consumers with high WMC are more able to process complex stimuli and retrieve previously presented information on a product quality. These consumers also have a higher tendency to retrieve more information from product scenarios with a high degree of experientiality.     

Social media bots and stock markets

This study examines the link between information spread by social media bots and stock trading. Based on a large sample of tweets mentioning 55 companies in the FTSE 100 composites, we find significant relations between bot tweets and stock returns, volatility, and trading volume at both daily and intraday levels. These results are also confirmed by an event study of stock response following abnormal increases in the volume of tweets. The findings are robust to various specifications, including controlling for traditional news channel, alternative measures of volatility, information flows in pretrading hours, and different measures of sentiment.