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1.
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
2.
Sebastián López Gustavo M. Callicó Félix Tobajas Valentín de Armas José F. López Roberto Sarmiento 《ETRI Journal》2008,30(6):862-864
This letter presents a novel approach for organizing computational resources into groups within H.264/AVC motion estimation architectures, leading to reductions of up to 75% in the equivalent gate count with respect to state‐of‐the‐art designs. 相似文献
3.
In this article, we describe a knowledge-based controlled platform using program supervision techniques. This platform eases
the creation and the configuration of video surveillance systems. Several issues need to be addressed to provide a correct
system configuration: (1) to choose, among a library of programs, those which are best satisfying a given user request, (2)
to assign a correct value for each program parameter, (3) to evaluate performances and to guarantee a performance rate which
is satisfactory regarding end-user requirements. This platform is composed of three main components: the library of programs,
the knowledge base and the control component. The knowledge is either given by experts or learnt by the system. The control
is generic in the sense that it is independent of any application. To validate this platform, we have built and evaluated
six video surveillance systems which are featured with three properties: adaptability, reliability and real-time processing. 相似文献
4.
5.
数字电视系统在提高图像质量方面已显示出极大的优越性。因此,世界各国电视台都已开始数字化的进程,中国也不例外。本文详细介绍了中央电视台第一个数字化演播室-800m^2演播室的视频系统,包括视频系统数字信号格式的确定,主要设备的特点以及演播室数字视频系统的主要特点等,供广大同行参考。 相似文献
6.
7.
提出了一种用双边带深侧槽的小尺寸圆形紧凑拉伸试样评定核压力容器(RPV)钢断裂韧性的单试作试验方法,给出了用该方法测定的两个厂家生产的核压力容器用A508CL3钢的断裂韧性参数,还与Charpy试样的试验结果及大尺寸标准试样的试验结果进行了比较。研究结果表明:用双边带深侧槽的小尺寸R-CT试样测得的断裂韧性值比相同恻槽深度预制疲劳裂纹Charpy试样的测试值更接近有效断裂韧性值,所以,用于核压力容器断裂韧性的监测是可行的。 相似文献
8.
Sanghoon Lee Chris Podilchuk Vidhya Krishnan Alan C. Bovik 《The Journal of VLSI Signal Processing》2003,34(1-2):149-166
By exploiting new human-machine interface techniques, such as visual eyetrackers, it should be possible to develop more efficient visual multimedia services associated with low bandwidth, dynamic channel adaptation and robust visual data transmission. In this paper, we introduce foveation-based error resilience and unequal error protection techniques over highly error-prone mobile networks. Each frame is spatially divided into foveated and background layers according to perceptual importance. Perceptual importance is determined either through an eye tracker or by manually selecting a region of interest. We attempt to improve reconstructed visual quality by maintaining the high visual source throughput of the foveated layer using foveation-based error resilience and error correction using a combination of turbo codes and ARQ (automatic reQuest). In order to alleviate the degradation of visual quality, a foveation based bitstream partitioning is developed. In an effort to increase the source throughput of the foveated layer, we develop unequal delay-constrained ARQ (automatic reQuest) and rate compatible punctured turbo codes where the punctual pattern of RCPC (rate compatible punctured convolutional) codes in H.223 Annex C is used. In the simulation, the visual quality is significantly increased in the area of interest using foveation-based error resilience and unequal error protection; (as much as 3 dB FPSNR (foveal peak signal to noise ratio) improvement) at 40% packet error rate. Over real-fading statistics measured in the downtown area of Austin, Texas, the visual quality is increased up to 1.5 dB in PSNR and 1.8 dB in FPSNR at a channel SNR of 5 dB. 相似文献
9.
10.
提出了一种利用PCM基群信道进行视频信号传输的方法,介绍了传输系统的工作原理,对视频编码器进行了较为详细的分析,并采用数字信号处理器作控制器,实现了视频信号的实时传输。 相似文献