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1.
The ability to detect gun and gun held in hand or other body parts is a typical human skill. The same problem presents an imperative task for computer vision system. Automatic observer independent detection of hand held gun or gun held in the other body part, whether it is visible or concealed, provides enhance security in vulnerable places and initiates appropriate action there. Compare to the automatic object detection systems, automatic detection of gun has very few successful attempts. In the present scope of this paper, we present an extensive survey on automatic detection of gun and define a taxonomy for this particular detection system. We also describe the inherent difficulties related with this problem. In this survey of published papers, we examine different approaches used in state-of-the-art attempts and compare performances of these approaches. Finally, this paper concludes pointing to the possible research gaps in related fields.  相似文献   
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本文通过分析反恐视频监控的需求,研究了普通红外线摄像机和激光摄像机的性能、铁路通信传输网通道容量和视频占用的资源量,推荐反恐视频监控方案采用数字激光摄像机。  相似文献   
4.
This study proposes an analytical and flexible terrain risk assessment method for military surveillance applications for mobile assets. Considering the risk as the degree of possibility of insurgent presence, the assessment method offers an efficient evaluation of risk in the surrounding terrain for military combat operating posts or observation posts. The method is designed for unmanned aerial vehicles as the surveillance assets of choice to improve the effectiveness of their use. Starting with the area map and geographical data, the target terrain is first digitized for space representation. Then the data of nine geographical parameters are used to formulate five contributing risk factors. These factors are incorporated in an analytical framework to generate a composite map with risk scores that reveal the potential high-risk spots in the terrain. The proposed method is also applied to a real-life case study of COP Kahler in Afghanistan, which was a target for insurgent attacks in 2008. The results confirm that when evaluated with the developed method, the region that the insurgents used to approach COP Kahler has high concentration of high-risk cells.  相似文献   
5.
The Fourth Amendment to the U.S. Constitution functions as a shield against excess governmental or police power by prohibiting unreasonable searches and seizures. Since its ratification, legal challenges have tempered this shield by frequently disputing the application of investigative processes and tools, including those that bypass the traditional – and simpler – analysis that focused on physical trespass. But recent technological advancements have prompted novel challenges and have forced the U.S. Supreme Court to adopt a parallel inquiry that evaluates society’s expectations of privacy as an alternate path to invoke the Fourth Amendment’s protections apart from any physical trespass. As revolutionary technology continues to present unique issues, this 200-year-old shield manifests a reflective luster as if polished by years of legal discourse that reveals the priorities of those who would interpret its text. Viewing the Fourth Amendment’s shield as a mirror illustrates not only the thoughts of the drafters that revolved primarily around protecting property interests but also the expectations of modern society with its insistence on promoting privacy. And where the drafters channeled their outrage against the loathsome writs of assistance in colonial times, later Americans continued to denounce the similarly invasive general warrants and attempts by investigators to expand the tools in their arsenal beyond constitutional bounds, especially in the surveillance context. Yet, the problems posed by new technology upon privacy concerns are best resolved by relying on the core principles supporting the Fourth Amendment, previous U.S. Supreme Court precedent, and current societal perspectives regarding privacy as a top priority proven by recently enacted legislation both foreign and domestic.

By applying a similar method to address advancing communication technology and its use as a surveillance tool in Carpenter v. United States, the Court turned this shield-become-mirror upon society to conclude that cell phone location information deserves Fourth Amendment protection because of its untiring comprehensiveness and its uniquely detailed nature. Moreover, nearly every American adult carries a cell phone with them almost all the time, making it possible to create a time-stamped map of any cell-phone-carrying-individual’s movements reaching back years and years. Unfortunately, the Carpenter Court did not extend this crucial protection far enough to protect all cell phone location data, and the unmistakable gap in its holding leaves a potential privacy vulnerability the exploitation of which could cause greater harm than all previously disputed surveillance technology combined because of cell phone usage’s general – near universal – applicability. Allowing cell phone location information to be obtained without probable cause and a proper search warrant not only fails to meet the spirit of the Fourth Amendment, it also begins to tarnish that shield such that it no longer reflects historical or current societal values, reducing its goal of protecting Americans to a hollow incantation of words left to languish as time (and technology) marches on.  相似文献   

6.
视频监控系统作为智能化工厂体系架构的子模块,在水泥工厂得到了广泛的部署和应用,为安全、生产流程等管理需求提供了远程可视化的技术支撑手段。为进一步提升工厂智能化水平,提高管理效率,本文提出了基于视频图像分析技术的智能监控预警平台的路线规划,实施步骤和方法,并对该平台的初步应用效果进行了量化评估,为后续平台建设提供科学决策依据。  相似文献   
7.
赵西安 《建筑技术》1997,28(2):126-128
根据国家标准《玻璃幕墙工程技术规范》JGJ102-96(1996年7月30日颁布,12月30日执行)规定的原则,介绍玻璃幕墙工程的监理工作内容、监理工作组织、分是细则  相似文献   
8.
1引言随着社会的进步,视频监控系统正在向全数字化时代发展。视频从前端图像采集设备输出时即为数字信号,并以网络为传输媒介,基于国际通用的TCP/IP  相似文献   
9.
This communication deals with an aspect of occupational hygiene in a factory producing granite cutting diamond wheels by sintering, in moulds, of fine cobalt powder. The factory has been studied between 1988 and 1991; the Department of Preventive and Occupational Medicine of the Local Sanitary Unit of Reggio Emilia has followed the evolution of the local exhaust ventilation equipment supplied by the employer in that period. At the same time, the following measurements and observations were carried out: (a) cobalt exposure by personal sampling, (b) airborne cobalt measurements by area sampling, (c) biological monitoring of cobalt in urine, (d) health surveillance.  相似文献   
10.
针对视频监控的特点与跟踪目标的强机动性,提出了一种新的基于概率模型的目标跟踪框架,从目标表观模型、系统动态模型以及系统观测模型3个方面对当前标准的粒子滤波目标跟踪方法进行了改进。首先,考虑人眼细胞的分布特点,基于人眼分布结构建立目标表观模型来提高跟踪系统抵抗局部遮挡的能力;然后,建立基于自适应目标运动的系统动态模型,提高跟踪算法对快速机动目标的鲁棒性;最后,采用实时更新的系统观测模型,有效避免目标在遇到遮挡、光照变化、剧烈变形等情况下发生的跟踪漂移现象。实验结果表明,本文算法的正确跟踪率可达98%;平均跟踪误差小于6个像元。实验证明本文算法在保证系统跟踪精度要求的同时,具有计算量小、抗干扰能力强等特点。  相似文献   
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