基于MSPF的实时监控多目标跟踪算法研究

近年来,实时监控下多目标跟踪作为智能交通系统(Intelligent transportation system,ITS)的重要组成部分受到关注.传统多目标跟踪方法通常具有处理速度慢、容易对交叉行进车辆产生误匹配等问题.本文首先对基于贝叶斯规则的车辆视频复杂背景的建模及运动目标的检测进行研究,在此基础上提出一种基于Meanshift粒子滤波(Mean shift particle filter,MSPF)的多目标跟踪算法,首先对每一目标车辆在下一帧可能出现的范围进行预测,对单目标和多目标情况采用不同的检测策略,避免了全局搜索,提高了跟踪速度;通过构造基于最新观测信息的重要性密度函数,提高了MSPF算法在复杂背景情况下追踪部分遮挡及交叉车辆的准确性和鲁棒性.仿真实验结果验证了所提出算法的有效性.     

鱼群启发的水下传感器节点布置

水下传感器网络(Underwater sensor networks, UWSNs)可用于海洋资源勘测、污染监控和辅助导航等领域, 已成为无线传感器网络方向的研究热点. 在开放式复杂的水下环境中监测目标具有高动态和不确定的特点, 节点如何根据环境和目标的变化自主调整位置, 以达到对监测目标的优化覆盖是一个关键问题. 本文描述了水下传感器节点布置问题, 定义了性能评价指标"事件集覆盖效能", 并提出了一种鱼群启发的水下传感器节点布置算法, 通过模拟鱼群行为, 并结合拥挤度控制, 使节点自主趋向并覆盖事件, 同时实现节点分布密度与事件分布密度相匹配. 大量对比仿真实验结果表明该算 法可以有效解决水下传感器节点布置问题, 并具有复杂度低、计算量小、收敛速度快和分布式可实现的优点.     

偏移校正的核空间直方图目标跟踪

针对传统均值漂移算法中核函数直方图对目标特征描述较弱、 跟踪窗不能动态调整容易导致目标跟偏或跟丢的缺点, 提出了一种改进的均值漂移跟踪算法.为提高目标特征描述的可靠性, 采用二阶空间直方图建立目标模型,以Bhattacharyya系数作为相似性度量; 通过偏移校正更新目标区域参数建立新的目标模型; 结合边缘与角点检测选取特征点建立仿射模型实现跟踪窗的调整; 根据卡尔曼残差判断目标是否被遮挡,从而选择卡尔曼滤波或是线性预测来确定目标位置. 实验结果表明,该算法可以准确地跟踪目标,对相似背景干扰、目标大小与方向的变化以及短时遮挡具有鲁棒性.     

Texture analysis of poly-adenylated mRNA staining following global brain ischemia and reperfusion

Texture analysis provides a means to quantify complex changes in microscope images. We previously showed that cytoplasmic poly-adenylated mRNAs form mRNA granules in post-ischemic neurons and that these granules correlated with protein synthesis inhibition and hence cell death. Here we utilized the texture analysis software MaZda to quantify mRNA granules in photomicrographs of the pyramidal cell layer of rat hippocampal region CA3 around 1 h of reperfusion after 10 min of normothermic global cerebral ischemia. At 1 h reperfusion, we observed variations in the texture of mRNA granules amongst samples that were readily quantified by texture analysis. Individual sample variation was consistent with the interpretation that animal-to-animal variations in mRNA granules reflected the time-course of mRNA granule formation. We also used texture analysis to quantify the effect of cycloheximide, given either before or after brain ischemia, on mRNA granules. If administered before ischemia, cycloheximide inhibited mRNA granule formation, but if administered after ischemia did not prevent mRNA granulation, indicating mRNA granule formation is dependent on dissociation of polysomes. We conclude that texture analysis is an effective means for quantifying the complex morphological changes induced in neurons by brain ischemia and reperfusion.     

Identification and classification of ERP critical failure factors in Iranian industries

Implementation of Enterprise Resource Planning systems (ERPs) is a complex and costly process, which usually results in serious failures. The majority of previous studies and research projects have been conducted in identifying ERP Critical Success Factors (CSFs) rather than Critical Failure Factors (CFFs). On the other hand, most studies have been devoted to developed countries, while in developing countries, many companies have moved towards using such systems. The majority of IT/IS management standards and guidelines have been developed by technologically-leading countries. But developing countries, which mostly confront with especial challenges, have a different condition from the implicit assumptions of leading countries. Iran is one of these countries that many of its ERP implementation projects led to failure. There is no comprehensive study that identifies ERP CFFs in Iranian industries. The main purpose of this study is to identify such factors and classify them to help other industries, consultants and implementers to prevent failures in the implementation of ERP projects. So, at first, with the semi structured interviews and literature reviews, 47 failure factors were identified. After that a questionnaire developed and sent to ERP project team members in Iranian industries that failed in their ERP projects. Robust Exploratory Factor Analysis (EFA) has been used for data analysis, which finally classified critical failure factors in seven groups named as vendor and consultant, human resources, managerial, project management, processes, organizational and technical. The results of this study have provided a very useful reference for scholars and managers to identify the relevant issues of ERP projects failure in developing countries.     

基于J48决策树算法的水质评价方法

提出一种以J48决策树算法为基础的水质评价方法。通过分析K最近邻法、贝叶斯分类法、向量空间模型法等常用的水质评价方法,针对某地区2008年的水质监测数据,采用J48决策树算法和单因子污染指数法对该地区水质进行计算,并对水质分类数据进行分类、属性清理和J48决策树参数的选择,以此建立模型。实验结果表明,该方法的交叉验证率约为95%,具有较好的分类评估效果。     

子坝布置优化对尾矿坝稳定性影响分析

尾矿库是矿山重要设施,其安全影响周围人员和财产安全.堆积坝子坝布置是影响尾矿坝稳定性的因素之一.利用FLAC软件采用强度折减法分析了子坝高度和子坝坡比对尾矿坝安全系数影响.结果表明,子坝坡比不变条件下,尾矿坝安全系数随堆积坝子坝高度升高而降低.在子坝高度不变条件下,尾矿坝安全系数随子坝坡比增加而增大.分析成果对尾矿坝设计及现场管理具有一定的应用价值.     

齐齐哈尔市粮食增产潜力影响要素分析及产量预测

影响粮食产量的因素众多,各因素之间相互制约,使得对粮食增产潜力的研究变得非常复杂。主成分分析法作为处理变量间多相关性的一种方法,能够将多要素指标重新组合成新的互相无关的几个综合指标,从而以较少的综合指标尽可能多地反映原来指标的信息。应用主成分分析法对齐齐哈尔市粮食产量影响要素进行分析,结果表明,粮食播种面积、粮食单产、农田成灾面积3个要素在齐齐哈尔市粮食增产中起着关键作用。最后通过建立粮食增产回归模型,根据相关规划数据,对齐齐哈尔市未来的粮食产量进行了预测。     

枣棉间作的生态效应对棉花产量的影响

在气候干燥、风沙危害严重的塔里木盆地腹地———阿克苏市研究枣棉间作对棉花的生态环境因子及产量的影响,揭示环塔里木盆地干旱区枣棉间作系统中光照、空气温湿度、风速等生态因子的变化情况以及水平分布特征,探讨间作对棉花产量的影响,分析枣棉间作系统的经济收益.2010年,在枣棉共生期间,使用Vantage Pro2自动气象站和KS4000手持气象站观测光照强度、空气温湿度、风速和风向等气象因子,利用LAI2000冠层分析仪观测光合辐射,棉花采收前进行测产.间作系统的日平均光照为71.78%;光合有效辐射方面表现为距离枣树越远越高,反之则越低,大小关系为：W-165cm〉E-155cm〉W-105cm〉E-95cm;间作系统的日平均气温降低2.7℃,地表温度平均比对照棉田降低4.3℃,空气相对温度高3.0%,土壤水分含量高3.13%～3.62%;间作系统的防风效能达到38.6%;对棉花有一定的减产,但并不明显.枣棉间作作为新疆特有的果农间作模式之一,在很多方面表现出较强的优势,为环塔里木盆地特色林果产业的发展以及枣农间作模式提供借鉴.