基于混合高斯和HOG+SVM的行人检测模型

为了提高行人检测系统的检测率,提出了一种基于混合高斯背景建模结合方向梯度直方图(histogram of oriented gradient,HOG)+支持向量机(support vector machine,SVM)的行人检测模型.首先,采用混合高斯模型进行前景分割,有效提取出运动目标区域;然后,在行人识别部分通过缩小检测窗口尺寸来降低HOG特征维数;另外,利用误识别区域,对样本库的信息进行二次更新,以优化SVM分类器;最后,以随机视频帧为测试样本进行模型性能验证.结果表明,在保证检测率和检测速率的情况下,该混合高斯结合HOG+SVM模型的误检率仅为4%,说明该模型能够在复杂场景下实时准确地进行行人检测.     

一种邻帧匹配与卡尔曼滤波相结合的多目标跟踪算法

传统目标跟踪算法很难在户外视频中进行行人实时跟踪及人流量统计,针对该问题,提出一种联合邻帧匹配与卡尔曼滤波器的多目标跟踪算法。该算法首先以方向梯度直方图(HOG)为特征的自适应推进(Adaboost)分类器进行行人人头检测,进而采用卡尔曼滤波进行行人轨迹预测,并应用邻帧匹配算法对该目标运动轨迹进行校正。在邻帧匹配法中,本文新颖的将跟踪过程中的目标匹配问题转化为基于匈牙利算法的指派问题。因邻帧匹配法能更好地区分不同待匹配目标的特征,较传统跟踪算法,能更好的避免误匹配、漏匹配等问题,提高了目标跟踪的准确率,实验证明,该监控系统准确率高,且能满足扶梯监控系统应用场景下的鲁棒性、实时性要求。     

采用HOG特征和机器学习的行人检测方法

针对基于方向梯度直方图(HOG)/线性支持向量机(SVM)算法的行人检测方法中存在检测速度慢的问题,提出一种将HOG特征与Adaboost-BP模型相结合的行人检测方法.利用边缘检测技术快速检测出行人候选区域,提取出多尺度多方向的HOG特征,利用Adaboost算法训练多个反向传播神经网络用于构建强分类器,实现对测试样本图像的检测识别.结果表明:文中方法具有更高的检测率、更低的误报率和漏检率,具有较好的检测效果.     

利用Camshift与TLD框架的多目标视频跟踪算法

由于跟踪器采用的是基于金字塔Lucaks-Kanade光流法,需要在相邻帧之间对目标的运动进行跟踪,运算量较大,因此提出了采用轻量级跟踪算法Camshift作为TLD算法框架中的跟踪器模块,来提高跟踪模块运行效率。而TLD框架的检测器在跟踪器追踪失败时需要检测大量数目的子窗口,因此利用背景差分方法进行前景检测,可以减小检测范围和数目。TLD算法本身是对单目标的长时间跟踪,提出基于多线程机制TLD算法,针对每一个跟踪目标建立相应的线程对其跟踪。经过实验验证,与原算法相比,优化算法使得对多目标实时跟踪性能得到一定提升。     

基于三帧差分法与质心匹配的行人自动计数算法

为了实现对视频序列中人流量进行实时、准确的检测与跟踪,提出了一种基于三帧差分法的行人质心匹配的行人检测与跟踪算法.采用改进的三帧差分法实现对运动目标信息的检测,然后根据运动目标的信息进行行人面积与质心的计算,并根据质心最近距离匹配、运动方向一致性、越界检测的原则对行人进行跟踪.实验结果表明,该算法在不降低检测效果的情况下明显提高了行人检测与追踪的效率.     

基于多个相关滤波器的行人跟踪尺度算法

外观、尺度变化是行人跟踪的难点，解决行人多尺度跟踪问题是增强算法实用性的关键因素.在KCF(kernel correlation filter)算法的基础上，本文采用多个相关滤波器(如头部、臀部)辅助身体躯干滤波器的匹配跟踪.通过获得图像帧(除第一帧外)与初始帧的行人头部和臀部之间的距离变化率来缩放搜索面积，解决目标定位不准确和时间浪费的问题;通过调整目标框的尺寸，解决目标模板逐渐包括背景特征或者逐渐被局部特征取代的问题.在VOT2016的18个有明显尺度变化的行人场景视频序列上进行了测试，实验结果表明所提算法具有更高的跟踪准确率.     

结合特征点匹配的在线目标跟踪算法

提出一种结合特征点匹配的目标跟踪算法.首先,通过显著区域跟踪方法,解决算法对初始化目标框大小敏感的问题,提高样本选取质量,并降低背景杂波对跟踪器的影响.其次,采用中值流法跟踪和特征点匹配相结合的方法估计目标的尺度变化,并通过层级聚类方法剔除干扰点,解决跟踪器漂移及目标平面旋转跟踪失败等问题.最后,提出一种简单的检测器自适应尺度快速搜索目标方法加快检测速度.结果表明:所提方法有效地提高了TLD目标跟踪算法的跟踪鲁棒性,并在标准数据集上得到了很好的效果.     

输电线红外图像超分辨率复原方法

针对因相机抖动而影响输电线红外图像超分辨率复原效果的问题,提出结合SIFT(Scale Invariant Feature Transform)特征配准信息对低分辨率的输电线红外图像进行超分辨率复原.以4个相邻图像帧为例,首先选定一帧作为参考帧,将其他3帧与该帧图像进行SIFT特征配准,配准过程为特征点检测与初配准、RANSAC (Random Sample Consensus)去除误配准点和图像重采样.然后,对参考帧与图像重采样后的3帧图像进行超分辨率复原.实验结果表明,该算法与传统的超分辨率复原算法相比,重影率下降41％,具有更好的超分辨率复原效果.     

基于改进的HOG与Sobel-LBP融合的快速行人检测

行人检测是目标识别领域的一大难题,针对行人检测存在特征维度高、检测耗时和精度低等问题,文章提出使用多尺度分块方式将样本图片在3个尺度下分别分割成5个区域,在每个区域中根据行人轮廓置信模板和梯度方向量化权值进行二次加权统计得到梯度直方图(histogram of oriented gradient,HOG),并将其与Sobel边缘局部二元模式(Sobel edge local binary pattern,Sobel-LBP)算法相融合作为特征,然后采用线性支持向量机(support vector machine,SVM)分类方法学习得到行人检测分类器,最后使用滑动窗口法检测出行人。在MIT和INRIA库上的实验证明,该特征在学习和检测速度上都比HOG等方法有明显优势,能有效、准确、快速地检测行人。     

基于SVM和序列联配的攻击特征提取方法

针对序列联配应用于攻击特征提取时的碎片和噪声干扰问题,采用SVM分类器将多攻击样本转换成单一攻击样本,以减少联配过程中的噪声序列;在两序列联配Smith-Waterman算法的基础上,改变空位罚分方式,引入连续匹配字符奖励,提出一种改进的Smith-Waterman(ISW)算法.结合SVM分类器与ISW算法构建攻击特征提取模型.研究结果表明:该模型的联配结果能准确地表达攻击特征,降低检测系统的误报率.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with     

Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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An on-line scaling method for improving scalability of a database cluster

The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.     

An improved R-tree based on childnode''s probability

R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).     

Integrating GIS Web services based on mediating architecture

The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.     

Tracking data management using topology of moving object database system for moving object constrained trajectory in LBS application

Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.