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排序方式: 共有2410条查询结果,搜索用时 46 毫秒
1.
针对现有基于视频监控的人流量统计方案成本高、算法复杂且不利于个人隐私保护的局限性,利用毫米波雷达体积小、成本低、分辨率高的特点,提出了一种基于双时间点检测的人流量监测方法。该方法先获取人体目标散射点位置和多普勒频移信息来构成点云数据,然后根据多普勒频移正负来判断人体的运动方向,并筛选具有高多普勒频移值的点云数据以降低干扰点对聚类结果的影响;在双时间点对特定区域内人员数量进行统计,并根据双时间点之间所获取的点云数据聚类结果对所统计人员数据进行修正。实验结果表明,该方法能够用匿名的方式以较高的正确率统计人员进出。  相似文献   
2.
Crowd counting with density estimation has been an active research community due to its significant applications in the fields of public security, video surveillance, traffic monitoring. However, Crowd counting for congested scenes often suffers from some obstacles including severe occlusions, large scale variations, noise interference, etc. In this paper, using the first ten layers of a modified VGG16 and dilated convolution layers as the framework, we have proposed a CNN based crowd counting and density estimation model improved by the attention aware modules with residual connections. To tackle the problem of noise interference, convolutional block attention modules have been introduced into the deep network to segment the foreground and background to focus on interest information, refining deeper features of the input image. To improve information transmission and reuse, residual connections are utilized to link 3 attention blocks. Meanwhile, dilated convolution layers keep larger reception fields and obtain high-resolution density maps. The proposed method has been evaluated on three public benchmarks, i.e. Shanghai Tech A & B, UCF-QNRF and MALL, achieving the mean absolute errors of 64.6 & 8.3, 113.8 and 1.68, respectively. The results outperform some existing excellent approaches. This indicates that the proposed model has high accuracy and better robustness, which is suitable for crowd counting and density estimation in various congested scenes.  相似文献   
3.
We present new parallelization and memory-reducing strategies for the graph-theoretic color-coding approximation technique, with applications to biological network analysis. Color-coding is a technique that gives fixed parameter tractable algorithms for several well-known NP-hard optimization problems. In this work, by efficiently parallelizing steps in color-coding, we create two new biological protein interaction network analysis tools: Fascia for subgraph counting and motif finding and FastPath for signaling pathway detection. We demonstrate considerable speedup over prior work, and the optimizations introduced in this paper can also be used for other problems where color-coding is applicable.  相似文献   
4.
The rainflow counting algorithm for material fatigue is both simple to implement and extraordinarily successful for predicting material failure times. However, it neglects memory effects and time-ordering dependence, and therefore runs into difficulties dealing with highly intermittent or transient stochastic loads with heavy tailed distributions. Such loads appear frequently in a wide range of applications in ocean and mechanical engineering, such as wind turbines and offshore structures. In this work we employ the Serebrinsky–Ortiz cohesive envelope model for material fatigue to characterize the effects of load intermittency on the fatigue-crack nucleation time. We first formulate efficient numerical integration schemes, which allow for the direct characterization of the fatigue life in terms of any given load time-series. Subsequently, we consider the case of stochastic intermittent loads with given statistical characteristics. To overcome the need for expensive Monte-Carlo simulations, we formulate the fatigue life as an up-crossing problem of the coherent envelope. Assuming statistical independence for the large intermittent spikes and using probabilistic arguments we derive closed expressions for the up-crossing properties of the coherent envelope and obtain analytical approximations for the probability mass function of the failure time. The analytical expressions are derived directly in terms of the probability density function of the load, as well as the coherent envelope. We examine the accuracy of the analytical approximations and compare the predicted failure time with the standard rainflow algorithm for various loads. Finally, we use the analytical expressions to examine the robustness of the derived probability distribution for the failure time with respect to the coherent envelope geometrical properties.  相似文献   
5.
朱高建 《中国矿业》2021,30(S1):182-183
针对采厂矿车翻卸人工计数可靠性低、安全风险大等问题,提出一种矿车翻卸自动计数系统设计方案,以JRF33铁路车号识别装置为载体,以RS485为通讯协议,对采集数据进行统计分析。结果显示,计数系统运行良好,翻卸数据采集及时、准确、完整。系统对采矿原料运输数据统计、分析应用和生产指导有一定的指导意义。  相似文献   
6.
Lithium iron phosphate battery (LIPB) is the key equipment of battery energy storage system (BESS), which plays a major role in promoting the economic and stable operation of microgrid. Based on the advancement of LIPB technology and efficient consumption of renewable energy, two power supply planning strategies and the china certified emission reduction (CCER) model are proposed respectively. Based on it, the multi-objective planning optimization model with economic benefits, environmental benefits and power supply stability as the objective function is established for the first time, and the Newton Weighted Sum Frisch method (NWSFA) solution model is adopted. In the planning process, rain flow counting method is used to research the life of BESS, which improves the accuracy of energy storage annual cost calculation. A park in northern China is taken as a case study to demonstrate the application of this model. The simulation results show that the annual economic operating cost of BESS is decreased by 18.81%, the energy supply reliability is increased by 0.15%, and the optimal electricity price adjustment ratio of the system is 15%.  相似文献   
7.
Pedestrianization was an established concept among modernist architects and planners long before the first post-war pedestrian malls were built in North American downtowns. Post-war pedestrian-oriented suburban shopping malls, such as Northland near Detroit, MI and Northgate in Seattle, WA, linked retail success to the pedestrian shopping experience. This propelled the existing but then-untested assumption that planning downtowns to mimic suburban shopping centres by pedestrianizing main streets would revitalize downtown retail districts. Despite the modern origins of the pedestrianization concept, the rhetorical cues of post-war architects and planners in North America mask its modern roots and employ nostalgic imagery of pre-industrial European urbanism, implying European origin of the concept. Although imagery of European charm became a means of packaging modernist ideas of pedestrianization, the design proposals rarely referenced or replicated actual European precedents. Furthermore, while much research implies a linear transfer of pedestrianization ideas from Europe to North America, professionals in Europe also looked to North American shopping malls and pedestrian streets for guidance in addressing their own challenges with accommodating automobiles in downtowns.  相似文献   
8.
二次世界大战后欧洲城市开始进行步行街建设,进入70年代步行街在西方国家大量流行。我国在90年代开始进行城市步行街的规划建设。本文在总结国内外步行街发展的原因以及城市中心步行环境的类型的基础上,提出城市中心步行空间规划设计要点。  相似文献   
9.
本文总结了北京王府井东方广场建设的经验与教训,指出商业步行街是城市特色组成的重要单元,其建设应尊重群体意识,并针对主题性商业步行街的文化特色展示提出相应设计原则。  相似文献   
10.
赵京飞  赵冰  滕熙 《山西建筑》2006,32(1):46-47
从步行街的产生和发展出发,论述了步行街的基本功能和特点,并谈到了在步行街设计中应考虑的相关要素,通过国内几处典型步行街情况的介绍,得出当前我国步行街设计和建设中存在的问题.并针对问题提出了景观空间整合应遵从的原则。  相似文献   
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