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1.
环境预警制度蕴含了一项使行政权力合法扩张的"对应性架构",即预警级别与"强制型"或"限制型"措施之间的充分必要关系。在制度运行过程当中,环境行政权力却出现了"选择性失语"和"运动式肆意"的问题,具体表现为:一是预警级别发布时的"隐匿"与"从轻",从而对公民健康权益保护不足;二是预警状态下环境行政权力的扩张过度,使得对个人自由与企业经济自由侵害过度。由于环境治理领域"被害人-加害人"二元对立关系的模糊化、趋同化甚至同一化,传统公法学体系中的权力制约理论无法对预警状态下多样化和多层次性的行政权力进行有效地规制。那么,便有必要对现有的环境预警制度进行修正与纠偏。因此,可以从"对应性架构"的载体及其前后两端入手,对环境预警制度进行法治化建构。具体而言,对环境预警的载体"应急预案"进行形式改造,提高环境应急预案的规范层级,完善环境应急预案制定、修改等程序性规定;明确不同预警级别设定的规范层级,将作为被宪法所保护的客观利益——生态环境利益与经济利益的边界——通过"前端"预警标准予以划分;对预警状态下行政权力的"外部"制约程序予以完善。基于预警级别标准体系的划分,可以通过司法程序对"后端"环境应急预案进行"附带性审查",同时,赋予私主体直接针对预警状态下具有"外化"法效力的内部行政行为提起行政诉讼的诉权。  相似文献   
2.
Most petrochemical units run under extreme conditions, such as high temperatures, pressures, and speeds. Consequently, the equipment operators may commit errors because the startup and shutdown processes usually involve complicated operation steps; moreover, the operators may lack experience in handling abnormal situations. Misoperation can lead to accidents, including fires and explosions. Thus, risk analysis for process operations and the development of preventive measures have become an effective means of avoiding misoperation-related accidents. However, it is challenging to ensure the comprehensiveness of risk-analysis results. In this paper, we present a method for misoperation monitoring and early warning in the startup and shutdown processes of petrochemical units. The mechanisms of misoperation occurrence are summarized based on investigations of serious accidents in the recent past. Knowledge regarding the mechanisms of misoperation is crucial for the risk analysis of petrochemical units. The potential risk information, such as causes, adverse consequences, key monitoring parameters, and prevention control solutions, should be acquired and be employed to construct an early-warning knowledge database. Furthermore, misoperation judgment rules need to be formulated to identify misoperations. The data obtained from the monitoring module, misoperation judgment rules, and analysis results can aid in developing schemes to avoid possible abnormal situations. This paper reports a misoperation monitoring and early-warning system for a hydrogenation unit. As demonstrated, conducting risk analysis to determine the potential operational risks and formulating misoperation judgment rules to analyze the process data are essential for enabling early warning. The application of this method will contribute to operational guidance, economic loss reduction, and accident avoidance.  相似文献   
3.
Objective: The objective of this study is to develop a novel algorithm on a mobile system that can warn drivers about the possibility of a collision with a pedestrian. The constraints of the algorithm are near-real-time detection speed and a good detection rate.

Method: Histogram of gradients (HOG)-based detection is widely used in pedestrian safety applications; however, it has low detection speed for real-time systems. Hence, it has no direct usage for mobile systems. In order to achieve near-real-time detection speed, partial Haar transform predetections are applied to an image before HOG detection. The partial and HOG detections are merged and a score-based confidence level is defined for the final detection phase. In this way, the outcome is prioritized and different warning levels can be issued to warn the driver before a possible pedestrian collision.

Results: The proposed algorithm provides an increase in detection speed (from 46 to 76 fps) and detection rate (from 80 to 91%) with respect to HOG-based pedestrian detection. It also improves confidence of the results by multidetection merging and score assignment to detections.

Conclusions: Performance improvement of the algorithm is compared with respect to state-of-the-art detectors/algorithms. Based on the detection rate and detection speed performance, it can be concluded that the proposed algorithm is suitable to be used for mobile systems to warn drivers about the possibility of collision with a pedestrian.  相似文献   

4.
为研究在道路突发危险场景下先进驾驶辅助系统的不同警告方式对驾驶人应激反应能力的影响,利用自主开发的驾驶人应激反应能力测试软件,以计算机模拟与驾驶模拟器为试验平台,以实际驾驶视频为试验场景,选取操作准确率和反应时间为测试指标,分析不同警告方式下驾驶人的应激反应能力。研究结果表明:视觉警告可有效缩短应激反应时间;视听觉组合警告中,视觉警告占主导作用,听觉警告起辅助作用;在真实场景视频试验环境下,驾驶模拟器模拟试验的操作效果优于计算机模拟试验。  相似文献   
5.
为解决机场实地应急演练中存在的成本消耗高、不安全、扩展性差等问题,研发基于VR技术的机场应急救援虚拟演练平台。平台采用模块化设计方案,并通过定义平台操作流程支持虚拟演练操作。采取分细节度的场景构建方法,运用细节层次模型以3层不同细节度模型方案将虚拟灾害场景划分为3类,同时利用Unity3D粒子系统控制机制实现火灾及灭火粒子特效的模拟,运用双顶层本体模型构建机场应急预案本体模型(AERPO),并利用XML Spy建立存储模型,且支持基于典型场景模型编辑形成整个灾害场景。结果表明:平台模块设置科学、场景效果合理,有助于提升演练人员应急处置能力。  相似文献   
6.
Objective: The objective of this study was to identify and quantify the motorcycle crash population that would be potential beneficiaries of 3 crash avoidance technologies recently available on passenger vehicles.

Methods: Two-vehicle crashes between a motorcycle and a passenger vehicle that occurred in the United States during 2011–2015 were classified by type, with consideration of the functionality of 3 classes of passenger vehicle crash avoidance technologies: frontal crash prevention, lane maintenance, and blind spot detection. Results were expressed as the percentage of crashes potentially preventable by each type of technology, based on all known types of 2-vehicle crashes and based on all crashes involving motorcycles.

Results: Frontal crash prevention had the largest potential to prevent 2-vehicle motorcycle crashes with passenger vehicles. The 3 technologies in sum had the potential to prevent 10% of fatal 2-vehicle crashes and 23% of police-reported crashes. However, because 2-vehicle crashes with a passenger vehicle represent fewer than half of all motorcycle crashes, these technologies represent a potential to avoid 4% of all fatal motorcycle crashes and 10% of all police-reported motorcycle crashes.

Discussion: Refining the ability of passenger vehicle crash avoidance systems to detect motorcycles represents an opportunity to improve motorcycle safety. Expanding the capabilities of these technologies represents an even greater opportunity. However, even fully realizing these opportunities can affect only a minority of motorcycle crashes and does not change the need for other motorcycle safety countermeasures such as helmets, universal helmet laws, and antilock braking systems.  相似文献   

7.
本系统基于气体浓度光学分析方法理论朗伯-比尔(Lambert-Beer)定律、光谱气体检测技术开发,实现了对煤矿火灾与瓦斯灾害超前预警、灾害产生的有毒有害气体实时监测和煤矿环境气体爆炸危险性辨识,对于煤矿灾害防治、救灾过程中杜绝次生灾害,保障煤矿工人及救护队员的生命安全,促进煤矿安全生产具有重要意义。  相似文献   
8.
为实现人群密集场所客流安全隐患早发现,辅助管理人员早决策,人群聚集风险区早疏散,提升对灾难的预见性和主动性。在国内外人群异常聚集监测预警现状分析基础上,对比分析得出监控视频分析技术是解决人群密集场所精准预警难题较为理想的解决方案;构建以视频智能分析的人群计数、密度估计、行人追踪、活动烈度识别为核心技术的人群密集场所风险预警技术框架;将该技术框架应用到某大型商圈的商业街区,获得监控区域内的人群总数、密度分布、行人轨迹和异常活动等特征。结果表明:提出的基于视频分析的人群密集场所风险预警技术框架可为城市大型商圈、交通枢纽、大型活动场所等城市公共场所的安全管理提供参考和借鉴。  相似文献   
9.
我国高速公路周边土壤重金属污染现状及研究进展   总被引:2,自引:0,他引:2  
以我国高速公路周边土壤重金属为研究对象,综述了我国高速公路周边土壤重金属污染特征、影响因素、来源、环境风险及其研究进展。高速公路周边土壤主要受Pb、Cd、Cr、Cu、Zn等重金属污染,主要呈现指数分布、偏态分布和两者混合分布等特点,并且受到土地利用、风向、地形、车流量等多种因素的综合影响。土壤重金属的来源除了受成土母质等自然因素影响以外,公路交通和周边工农业活动也会对其来源产生较大影响。传统的土壤重金属评价方法主要采用单因子指数法、地累积指数法、生态风险评价法等对重金属的污染等级和环境风险进行评价。未来的研究应将重金属形态分析、空间和地统计分析、重金属稳定同位素示踪和源解析模型以及预测模型等多种手段相结合,开展高速公路周边土壤重金属的污染特征、时空分布、来源及预测预警研究等,为我国高速公路沿线工农业生产布局及其土壤重金属污染防控提供科学依据和决策支撑。  相似文献   
10.
一种新的海洋生物地球化学自主观测平台:Bio-Argo浮标   总被引:1,自引:0,他引:1  
借助于强大的全球海洋观测网络——Argo计划,生物光学浮标Bio-Argo将成为一种全新的海洋生物地球化学自主观测平台,对未来的海洋观测与海洋研究将产生巨大的影响。本文以法国的PROVBIO为例,详细介绍了Bio-Argo浮标的结构设计、观测数据、工作模式、传输与通讯、以及数据质量控制等方面的问题,为我国的Argo计划和海洋观测方法提供有益的借鉴。  相似文献   
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