伯努利滤波在单站无源跟踪中的应用

外辐射源雷达系统具有隐蔽性好、反隐身能力及抗干扰能力强等优点，但其中高频频段信号普遍存在距离分辨率较差的问题。通过建立仅利用目标多普勒信息的测量模型，将基于随机有限集的伯努利滤波算法应用于以多个视距外短波广播发射站、单个近距离接收站为背景的单站无源雷达系统中，同时克服了传统跟踪方法中复杂的数据关联，进而提高了跟踪效果。仿真结果表明，该方法能在大量虚警下仅利用多普勒信息实现对运动目标的有效跟踪和定位。     

融合梯度和色度信息的分块均值漂移目标跟踪

针对在相似颜色干扰场景下传统均值漂移目标跟踪鲁棒性差的缺陷,提出Prewitt梯度和色度信息融合的分块均值漂移跟踪算法。首先,对跟踪框进行分块,并提取当前帧各子块特征;其次,利用Bhattacharyya距离计算参考目标区域与候选区域间各子块对应的相似程度,根据其相似程度分配各子块的权值,并通过融合规则对各子块相应特征进行融合构成新子块特征,在此基础上,将子块特征选择串接方式作为最终目标特征;最后,采用均值偏移原理迭代估计最终目标位置信息。实验结果表明,当场景中存在相似颜色干扰的情况下,相对于经典均值漂移算法,其准确度提高了84%左右。     

强跟踪Unscented滤波器及其在无源跟踪中的应用

本文研究用递推算法实现只测量到达角和多普勒频移的无源双基地雷达的目标运动分析。基于Unscented卡尔曼滤波器和强跟踪滤波器,提出了一种新的强跟踪Unscented滤波器算法。新算法在无源双基地雷达目标跟踪的仿真实验中显示了高精度鲁棒滤波的性能。     

基于电子标签的物流信息管理系统设计与实现

针对物流企业对货物跟踪和仓储盘点管理难的问题,采用GPS和ZigBee技术设计了物流信息管理系统,系统由货物节点、货车节点、仓库节点和物流信息管理中心组成。设计的专业物流信息管理软件功能强大、操作简便,能够对仓库内所有货物进行盘点,实现了物流企业对运输货物的实时跟踪,大大提升了物流行业的工作效率和管理水平。     

二次监视雷达跟踪近程目标的新方法

针对近程目标的机动特性以及在近距离询问信号饱和使应答机抑制等因素造成二次监视雷达不能稳定跟踪目标的现象，提出了一种新的跟踪方法，采用询问编排、功率控制等措施让应答机能有效应答，并通过近程跟踪滤波、航迹融合来实现对近程目标的稳定跟踪。该方法提高了系统的跟踪效能，近程目标的应答率提高到了80%左右，适合于二次监视雷达系统对近距离目标跟踪要求严苛的场合。该方法已在实际工程中成功应用。     

Improving carbon offsetting appeals in online airplane ticket purchasing: testing new messages,and using new test methods

ABSTRACT

Voluntary carbon offsetting by air passengers could help counteract environmental damage caused by air travel. But adoption rates among air travellers are low. This study (1) develops new communication messages which counteract barriers to carbon offsetting identified in prior studies, and (2) tests their effectiveness using psychophysiological and attitudinal measures, a technique new to sustainable tourism research methodologies. Results point to low levels of traveller awareness of carbon offsetting schemes, the primary need for any message to attract the air passengers’ attention, the superiority of pictorial and short textual information as well as the identification of particularly effective content. The study makes three key contributions: (1) it highlights the critical importance of awareness raising as a precursor of behavioural change, (2) it offers tangible recommendations for improving carbon offsetting messages, and (3) it demonstrates the usefulness of psychophysiological measures for pre-testing alternative social marketing messages aimed at increasing environmentally sustainable tourist behaviour across a range of applications. Findings of considerable practical importance include refinements of current messages to increase both attention levels and emotional arousal, and the positive impact of promoting additional social co-benefits alongside environmental benefits. Future valuable research themes using psychophysiological and attitudinal measures are suggested.     

Are people emotionally aroused by hypothetical medical scenarios in experiments? An eye tracking study with pupil dilation

Background: Many studies on the communication of medical risks use hypothetical medical scenarios. The results of these scenarios should have sufficient predictive accuracy to be generalized to real life; thus, it is important to know whether hypothetical medical scenarios work and whether there is a relationship between risk level and emotional arousal. Methods: In an eye tracking experiment (N = 67), we investigated the influence of a simple hypothetical medical scenario on pupil dilation, a measure of emotional arousal. In this medical scenario, the participants were shown three risk levels (low, middle, and high) and had to estimate the probability that a hypothetical patient has colon cancer. They were also given a non-medical scenario that controlled for changes in illumination and cognitive workload. Therefore, we supposed that the difference in pupil diameter between the medical and the non-medical scenario was due to emotional arousal. Results: We found that our hypothetical medical scenario had a significant effect on pupil diameter. The mean values of the mean pupil diameter in the first fifth of the fixations were higher for all risk levels in the medical scenario than in the non-medical scenario. In a more detailed analysis of the difference in pupil diameters between the two scenarios, we detected that, for the high-risk level, the emotional difference values (between the medical and non-medical scenarios) differed significantly from zero. Furthermore, we found that higher risk levels lead to higher emotional arousal and higher probability estimates. Conclusions: Even simple hypothetical medical scenarios cause emotional arousal. Thus, hypothetical medical scenarios work, and the results of studies not using real patients can be generalized to real medical situations.     

中小型制造业订单追踪与供应商选择支持研究

从企业采购角度出发,分析了中小型制造业现有采购流程并找出制约其发展的因素,提出了一种基于时间节点的订单追踪方法和供应商选择方法,为中小型制造业提高按期交付能力和质量控制能力提供一种新的解决思路。     

Validating Bluetooth logging as metric for shopper behaviour studies

The ability to track shoppers as they move through retail environments using signals emitted by their communication devices kindles the interest of practitioners and researchers. This data collection method is cheap and has the ability to supply big data for shopper insights. However, this non-probabilistic sampling method can possibly under- or over-represent certain groups of the shopper population. This study assesses the validity of the data describing the length of shopping trips and representativeness of the sample of shoppers carrying Bluetooth-enabled devices. The authors track unique Bluetooth logs in-store and compare to simultaneously collected data from a manual, systematic sample of 324 shoppers observed and interviewed in the same supermarket. A comparison of the results obtained from the two samples (auto-logging and manual systematic) drawn from the same population indicates automated Bluetooth tracking produces very similar (r=.92, p<.001) trip lengths to that observed manually. Basket size, spend and occupation of Bluetooth trackable shoppers are similar to those with no Bluetooth-enabled devices. These findings present compelling evidence that the Bluetooth auto-logging method holds great potential for retail practice and research. An expected under-representation of the oldest demographic (66 y.o. and over) in the Bluetooth discoverable sample calls for complementary methods of data collection to minimise representation bias in real-time tracking technologies for shopper research. The benefits of using auto-logging data describing shopping trip length for retail practitioners and researchers are discussed.     

电流法在天线传动系统故障及跟踪性能分析中的应用

分析了天线传动系统影响电机电流特性的因素。提出了天线正常跟踪卫星的电流特性 标准,电流在6 A以下属于正常范围。利用电机电流分析法,对测控天线传动系统的周期性 故 障、阻尼增大故障以及系统级故障进行定位判断,提出了产生故障的因素。同时,分析了上 述 三类故障对测控天线的跟踪性能的影响。结果表明,电机电流分析法可以对天线传动系统的 故障进行预判断,有效避免系统级故障的发生,确保天线运行在良好的跟踪状态。