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221.
基于视频识别技术开发无信号交叉口安全预警系统原型,在Visual Studio 2010开发环境下,借助halcon8.0图像处理算子,应用背景差法识别与跟踪运动车辆,实时采集车速、加速度、距离等微观交通信息,建立无信号交叉口安全通行模型实现动态安全预警功能,利用模型车辆测试系统的预警可靠性,在参数设置合理的条件下取得了87%的预警成功率。  相似文献   
222.
SCE(Service Control Engines)为Cisco服务控制引擎产品,是软硬件结合的服务控制平台,支持互联网IP流量的分类、分析和控制。简单介绍了SCE在网络中的组网方案,并详细阐述该设备在宽带网络中的不同应用。  相似文献   
223.
王佐  吴蔚 《世界海运》2006,29(4):27-28
通过介绍ISM规则所要求船公司管理复查的目的、内容、信息输入及管理复查的实施步骤,强调管理复查作为安全管理体系自我完善的重要性,以引起船公司的足够重视。  相似文献   
224.
ISM规则下有关船舶适航的法律适用问题   总被引:1,自引:0,他引:1  
郑曦 《世界海运》2006,29(4):47-49
海事司法实务中,作为国际公约的ISM规则在国内适用,势必对船舶适航的认定产生重大影响。肯定了ISM规则对航行于国际航线的我国船舶适用所具备的条件,并阐明在船舶适航方面ISM规则适用的法律依据。  相似文献   
225.
移动总机业务是一种基于移动智能网技术实现的增值业务。本文就其业务特征及实现进行了探讨,并与综合VPMN业务做了比较。  相似文献   
226.
《珠江三角洲地区改革发展规划纲要》的颁布实施,对珠三角地区经济社会的发展具有重要战略意义,为珠三角地区船舶工业和航运业的发展提供了历史机遇。本文以珠江三角洲地区相关的船检分支机构[主要以广州海事局(广东省船舶检验局广州分局)为例]如何把握这一历史时期,更好地履行船舶检验职责和体现公共服务职能,发挥专业优势为船舶工业和航运业发展服务,在服务地方经济建设的同时实现自身科学发展为课题进行思考,提出了相应的对策建议。  相似文献   
227.
Exposure to fine particulate matter from vehicle exhaust is associated with increased health risk. This study develops a new approach for creating spatially detailed regional maps of fine particulate matter concentration from vehicle exhaust using a dispersion model to better evaluate these risks. The spatial extent, diurnal, and seasonal patterns of concentration fields across Los Angeles County, California are evaluated and population exposure and exposure equity by race and income are investigated. The results demonstrate how this modeling approach can create new knowledge about vehicle emissions exposure. This approach also provides a method for proactively screening out regional plans, or specific projects within these plans, that are likely to cause air quality concerns. A proactive and regional air quality assessment can identify potential problems earlier in the planning process and a wider range of solutions, saving time, money and protecting public health. The detailed concentration maps can also be used to improve the siting of regulatory air quality monitors and provide more accurate exposure data for epidemiology studies.  相似文献   
228.
Mobile sensing enabled by GPS or smart phones has become an increasingly important source of traffic data. For sufficient coverage of the traffic stream, it is important to maintain a reasonable penetration rate of probe vehicles. From the standpoint of capturing higher-order traffic quantities such as acceleration/deceleration, emission and fuel consumption rates, it is desirable to examine the impact on the estimation accuracy of sampling frequency on vehicle position. Of the two issues raised above, the latter is rarely studied in the literature. This paper addresses the impact of both sampling frequency and penetration rate on mobile sensing of highway traffic. To capture inhomogeneous driving conditions and deviation of traffic from the equilibrium state, we employ the second-order phase transition model (PTM). Several data fusion schemes that incorporate vehicle trajectory data into the PTM are proposed. And, a case study of the NGSIM dataset is presented which shows the estimation results of various Eulerian and Lagrangian traffic quantities. The findings show that while first-order traffic quantities can be accurately estimated even with a low sampling frequency, higher-order traffic quantities, such as acceleration, deviation, and emission rate, tend to be misinterpreted due to insufficiently sampled vehicle locations. We also show that a correction factor approach has the potential to reduce the sensing error arising from low sampling frequency and penetration rate, making the estimation of higher-order quantities more robust against insufficient data coverage of the highway traffic.  相似文献   
229.
为了提高培训质量,对新公约下海上医疗救护培训现状及存在的问题进行分析.从统一教材、题库、实训项目及考评标准中内容、要求及运用情况进行实证对比.结果显示教材过于专业化和理论化;题库缺乏综合性、全面性和实用性;实训内容简单;评估形式复杂.指出教材应简单通俗而不失弹性;题库应强化案例及技能练习;实训内容应够用实用;考评应兼顾学员综合表现.  相似文献   
230.
This paper investigates punctuality at bus stops. Although it is typically evaluated from the point of view of bus operators, it must also account for users, as required in recent service quality norms. Therefore, evaluating punctuality at bus stops is highly important, but may also be a complex task, because data on both bus arrivals (or departures) and users must be taken into account and processed. Data on buses can be collected by Automatic Vehicle Location (AVL) systems, but several challenges must be addressed in order to use them effectively. Passengers data at bus stops cannot be derived from AVL, but they can be used to derive passenger patterns and need to be integrated into processed AVL data. This paper proposes a new punctuality measure defined as the fraction of passengers who will be served within an acceptably short interval after they arrive. A method is proposed to determine this measure: it provides (i) several rules to handle AVL collected data, (ii) a procedure integrating processed AVL data and potential passengers’ patterns and (iii) a hierarchical process to perform the punctuality measure on each bus route direction of a transit network, as well as for every bus stop and time period. The paper illustrates the experimentation of this method on more than 4,000,000 data of a real bus operator and represents outcomes by easy-to-read control dashboards.  相似文献   
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