基于多种视频特征的镜头边界检测算法

针对固定场景的视频,提出一种基于时空分割的视频分割算法.该算法在时域中利用Tophat形态学滤波得到视频对象的精确位置,在空域中采用基于t混合模型和贪婪EM的聚类算法进行单帧图像分割.将时域定位和空域分割结果结合,可以准确地将视频序列中感兴趣的运动目标分割出来.实验表明,该算法能够得到完整的视频对象,有一定的理论意义和实用性.     

四自由度并联跟踪台的软件关键技术

研究四自由度并联跟踪台中的软件关键技术,编写Matlab仿真程序对并联跟踪台进行参数化设计,利用Solidworks与ADAMS联合仿真软件获取并联跟踪台的运动学和动力学性能参数,通过对操纵杆的编程实现对并联跟踪台的手动控制。实验结果表明,四自由度并联跟踪台设计合理、运动灵活、手控效果好。     

交互式凸组合法的混合时滞不确定中立系统的稳定性

针对带分布时滞和离散时滞的不确定中立型系统进行稳定性研究. 基于交互式凸组合方法和下界引理, 通过构造恰当的李雅普诺夫泛函, 适当分割时滞区间, 处理一组由凸参数逆加权的正函数线性组合(交互式凸组合), 给出线性矩阵不等式形式的系统鲁棒稳定性判据. 该方法允许离散时滞为变时滞, 增强了系统的鲁棒性能. 数值算例验证了所得结果的有效性和合理性.

     

谈话节目语料库的构建与会话结构分析

口语语料库的建设是口语研究的基础工作,该文选择具有代表性的交谈式谈话节目《锵锵三人行》和对谈式谈话节目《鲁豫有约》作为语料,建立了一个小型的谈话节目语料库,并构建了包含五大类16小类的会话结构标注体系,对语料进行了会话结构的标注。统计得到打断结构309例,插入结构141例,重复结构111例,问答结构653/589例,阻碍—修正结构51/21例,反映了会话结构在数量上的不均衡分布,节目的形式、性质以及交际任务是会话结构分布的主要影响因素。会话结构组合具有模式性,该文使用Trigram方法对其组合情况进行了分析,发现语料中的高频组合是问答毗邻对,此外有大量的非毗邻性组合。会话结构组合模式不但反映出谈话节目的风格特点,还有助于分析会话中的功能性模块、会话策略的形成,进而更加深入地了解会话的运作机制。     

A model for simulating the performance and irrigation of green stormwater facilities at residential scales in semiarid and Mediterranean regions

Impervious areas change hydrological processes, reducing infiltration and evapotranspiration, and increasing direct runoff. Stormwater practices using green infrastructure are implemented locally to control runoff and preserve the hydrological cycle. Applying these techniques in semiarid and Mediterranean regions requires accounting for aspects related to the maintenance of green areas. This study develops the Integrated Hydrological Model at Residential Scale, a continuous model for representing the performance and irrigation of green stormwater facilities at residential scales. Among other relevant process, the model simulates evaporation from bare soil and redistribution between soil layers. Different components of the model were tested using laboratory and numerical experiments, and then an application to a case study and a sensitivity analysis were carried out. The model identifies significant differences in the performance of a rain garden with different vegetation, climate and irrigation practices and provides good insight for the maintenance needs of green infrastructure for runoff control.     

Design optimization of resource combination for collaborative logistics network under uncertainty

Collaborative logistics networks (CLNs) are considered to be an effective organizational form for business cooperation that provides high stability and low cost. One common key issue regarding CLN resource combination is the network design optimization problem under discrete uncertainty (DU-CLNDOP). Operational environment changes and information uncertainty in network designs, due to partner selection, resource constrains and network robustness, must be effectively controlled from the system perspective. Therefore, a general two-stage quantitative framework that enables decision makers to select the optimal network design scheme for CLNs under uncertainty is proposed in this paper. Phase 1 calculates the simulation result of each hypothetical scenario of CLN resource combination using the expected value model with robust constraints. Phase 2 selects the optimal network design scheme for DU-CLNDOP using the orthogonal experiment design method. The validity of the model and method are verified via an illustrative example.     

一种基于颜色特征的感兴趣目标提取方法

针对现有的感兴趣区域(ROI)提取方法边缘不清晰、区域不完整等问题,提出一种ROI提取方法.首先采用颜色局部特征的信息量大小衡量兴趣度的大小,然后融合颜色特征信息量图获得图像的显著图(SM),再进行阈值分割,得到显著值大的区域,即ROI.实验结果表明,该方法能有效地提取出感兴趣的对象,SM中目标区域的显著值均匀、边缘清晰;与人工标记的ROI比较,该方法召回率为79.71％,精度为78.53％,优于已有的ROI提取方法.     

AMSR-E卫星反演土壤湿度与ECWMF,NECP再分析土壤湿度比较分析

土壤湿度是气象学、气候学研究领域的重要环境因子和过程参数。AMSR-E可提供全球范围的较长时序的卫星反演土壤湿度产品,将ECWMF和NECP再分析资料与AMSR-E土壤湿度产品进行时空比较,在评价三者一致性的同时对AMSR-E土壤湿度进行检验,并进一步使用站点观测资料(土壤湿度、降水量)对中国区域的AMSR-E、ECWMF以及NECP土壤湿度进行检验。结果表明：全球及中国区域AMSR-E、ECWMF与NECP土壤湿度空间分布特征一致性较好,但与ECWMF、NCEP相比AMSR-E土壤湿度在数值上明显偏小,尤其当AMSR-E土壤湿度数值较小时,与另两者的差距较大;三者土壤湿度均与降水量有较好的对应关系,比较而言,ECWMF和NECP土壤湿度与降水量的对应关系更好;与站点土壤湿度相比,ECWMF和NECP土壤湿度偏大,AMSR-E土壤湿度偏小,全国范围内2009年159个站点统计结果显示:ECWMF、NECP与站点的均方根误差(0.107、0.124)小于AMSR-E的均方根误差(0.127)。     

基于概率算法的混流式水轮机转轮叶片组合优化模型

讨论了混流式水轮机转轮厂内制作时各叶片组合形式对转轮静平衡的影响,并在VB环境下基于概率算法的寻优方式,建立了叶片组合优化模型。该模型以各叶片的不平衡力矩为目标函数,使用概率算法进行搜索寻优[1],找出可接受的满意解。应用该模型进行叶片组合优化设计,并与已有机组相比,优化设计结果有明显的优越性,证明了该组合优化模型的有效性和实用性。     

Comparing three methods for modeling the uncertainty in knowledge discovery from area-class soil maps

Knowledge discovery has been demonstrated as an effective approach to extracting knowledge from existing data sources for soil classification and mapping. Soils are spatial entities with fuzzy boundaries. Our study focuses on the uncertainty associated with class assignments when classifying such entities. We first present a framework of knowledge representation for categorizing spatial entities with fuzzy boundaries. Three knowledge discovery methods are discussed next for extracting knowledge from data sources. The methods were designed to maintain information for modeling the uncertainties associated with class assignments when using the extracted knowledge for classification. In a case study of knowledge discovery from an area-class soil map, all three methods were able to extract knowledge embedded in the map to classify soils at accuracies comparable to that of the original map. The methods were also able to capture membership gradations and helped to identify transitional zones and areas of potential problems on the source map when measures of uncertainties were mapped. Among the three methods compared, a fuzzy decision tree approach demonstrated the best performance in modeling the transitions between soil prototypes.