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Pedestrians and cyclists are amongst the most vulnerable road users. Pedestrian and cyclist collisions involving motor-vehicles result in high injury and fatality rates for these two modes. Data for pedestrian and cyclist activity at intersections such as volumes, speeds, and space–time trajectories are essential in the field of transportation in general, and road safety in particular. However, automated data collection for these two road user types remains a challenge. Due to the constant change of orientation and appearance of pedestrians and cyclists, detecting and tracking them using video sensors is a difficult task. This is perhaps one of the main reasons why automated data collection methods are more advanced for motorized traffic. This paper presents a method based on Histogram of Oriented Gradients to extract features of an image box containing the tracked object and Support Vector Machine to classify moving objects in crowded traffic scenes. Moving objects are classified into three categories: pedestrians, cyclists, and motor vehicles. The proposed methodology is composed of three steps: (i) detecting and tracking each moving object in video data, (ii) classifying each object according to its appearance in each frame, and (iii) computing the probability of belonging to each class based on both object appearance and speed. For the last step, Bayes’ rule is used to fuse appearance and speed in order to predict the object class. Using video datasets collected in different intersections, the methodology was built and tested. The developed methodology achieved an overall classification accuracy of greater than 88%. However, the classification accuracy varies across modes and is highest for vehicles and lower for pedestrians and cyclists. The applicability of the proposed methodology is illustrated using a simple case study to analyze cyclist–vehicle conflicts at intersections with and without bicycle facilities. 相似文献
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自动闭塞设计的新理念 总被引:1,自引:0,他引:1
傅世善 《铁路通信信号工程技术》2004,(1):4-6
CTCS 技术规范的制定,对自动闭塞设计的传统理念和方法产生了冲击,探讨采用目标距离模式曲线方式控车后的自动闭塞的设计原则和方法,建议采用闭塞分区等长设计。 相似文献
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声纳目标特征级融合的主要任务是实现信息压缩、目标身份确定(分类) ,以利于实时处理、决策分析。基于数学模型的各种算法,由于情况复杂,往往很难建立。而人工神经网络通过样本的学习,具有存储记忆、在相似输入下能恢复记忆等特性,从而避免了烦琐而复杂的建模。在神经网络声纳目标识别前的噪声预处理方法中,选用了功率谱特征提取、双谱特征提取算法;在研究了提取的特征后,选取反向传播神经网络(BP)模型;在此基础上构造了BP神经网络,并对网络进行训练与测试,给出识别实验结果。仿真模拟分析证明,基于神经网络的声纳特征级信息的融合,对目标分类有一定效果,为进一步实现声纳信息融合奠定了基础 相似文献
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商业流程执行语言的研究与应用 总被引:1,自引:0,他引:1
商业流程执行语言(Business Process Execution Language for Web Services,简称BPEL4WS或BPEL)是一种基于XML的工作流定义语言,它使企业能够描述既能使用又能提供Web服务的复杂的业务流程.介绍BPEL4WS的基本概念,特点及如何利用BPEL4WS来构建商业流程处理系统. 相似文献
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曹虎 《铁路工程造价管理》2007,22(6):45-47,59
介绍目标管理在勘察设计企业的推行情况,充分肯定了推行目标管理的积极意义,并分析了目前目标管理中存在的不足及其主要原因。建议管理者要强力推动目标管理,大力宣传目标管理的理念、原理和方法,完全遵循SMART原则,调动全员参与的积极性,加强目标执行情况的考核。 相似文献
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利用数字图像来测定船模运动参数是一种成本低、精度高的方法。该系统利用数字图像技术实现了船模试验在自然光条件下的实时测量、实时数据处理和自动操纵控制。介绍了一套多CCD摄像机的船模自动测控系统,对电视图像变形修正、船模自动识别与跟踪等关键技术进行了详细的讨论。根据船模试验的特点提出了有别与一般目标识别跟踪的方法。 相似文献
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工作流技术在电网调度管理系统中应用 总被引:1,自引:0,他引:1
单立娟 《辽宁省交通高等专科学校学报》2010,12(6):34-36
本文简要介绍了工作流技术的基本概念及应用,并针对某电网调度管理系统设计并开发了一个工作流平台。通过引入工作流技术使系统的灵活性、可靠性、运行效率等方面得到了全面的改善。此平台已经投入使用,运转状态良好。 相似文献
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