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Camera Scheduling and Energy Allocation for Lifetime Maximization in User-Centric visual Sensor Networks

IEEE TRANSACTIONS ON IMAGE PROCESSING 2010年第8期19卷 2042-2055页

作者： Yu, Chao Sharma, Gaurav Univ Rochester Dept Elect & Comp Engn Rochester NY 14627 USA Univ Rochester Dept Biostat & Computat Biol Rochester NY 14627 USA

We explore camera scheduling and energy allocation strategies for lifetime optimization in image sensor networks. For the application scenarios that we consider, visual coverage over a monitored region is obtained by deploying wireless, battery-powered image sensors. Each sensor camera provides coverage over a part of the monitored region and a central processor coordinates the sensors in order to gather required visual data. For the purpose of maximizing the network operational lifetime, we consider two problems in this setting: a) camera scheduling, i.e., the selection, among available possibilities, of a set of cameras providing the desired coverage at each time instance, and b) energy allocation, i.e., the distribution of total available energy between the camera sensor nodes. We model the network lifetime as a stochastic random variable that depends upon the coverage geometry for the sensors and the distribution of data requests over the monitored region, two key characteristics that distinguish our problem from other wireless sensor network applications. By suitably abstracting this model of network lifetime and utilizing asymptotic analysis, we propose lifetime-maximizing camera scheduling and energy allocation strategies. The effectiveness of the proposed camera scheduling and energy allocation strategies is validated by simulations.

关键词： Camera scheduling energy allocation image sensor networks network lifetime visual coverage

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visual sensor network lifetime maximization by prioritized scheduling of nodes

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JOURNAL OF NETWORK AND COMPUTER APPLICATIONS 2013年第1期36卷 409-419页

作者： Hooshmand, M. Soroushmehr, S. M. R. Khadivi, P. Samavi, S. Shirani, S. Isfahan Univ Technol Dept Elect & Comp Engn Esfahan Iran McMaster Univ Dept Elect & Comp Engn Hamilton ON Canada

visual surveillance of a designated air space can be achieved by a randomly distributed camera sensor network spread over a large area. The location and field of view of each battery operated sensor, after a calibration phase, will be known to a central processing node. To increase the lifetime of the network, the density of distributed sensors could be such that a subset of sensors can cover the required air space. As a sensor dies another sensor should be selected to compensate for the dead one and reestablish the complete coverage. This process should be continued until complete coverage is not achievable by the existing sensors. Thereafter, a graceful degradation of the coverage is desirable. The goal is to elongate the lifetime of the network while maintaining a maximum possible coverage of the designated air space. Since the selection of a subset of sensors for complete coverage of the target area is an NP-complete problem, we present a number of heuristics for this case. The proposed methods are categorized in two groups. In one category, the sensors are prioritized based on their visual and communicative properties and the selection is performed according to the prioritizing function. In the other group, we propose traditional evolutionary and swarm intelligence algorithms. The performance of the proposed methods is evaluated through extensive simulations. (C) 2012 Elsevier Ltd. All rights reserved.

关键词： visual sensor network Directional sensors visual coverage Priority based algorithms Genetic algorithm PSO algorithm

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The functional organization of area V2, II: The impact of stripes on visual topography

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visual NEUROSCIENCE 2002年第2期19卷 211-231页

作者： Shipp, S Zeki, S UCL Wellcome Dept Cognit Neurol London WC1E 6BT England

We have examined the visuotopic organization of area V2 of macaque monkeys in relation to its modular construction, comprising repetitive cycles of stripes running perpendicular to the border with area V1. Receptive fields were plotted in anesthetised animals, mainly using long penetrations parallel to the V1 border crossing several stripes in dorsal V2 within the representation of paracentral, inferior visual field. We confirm that each set of modules (thick, thin, and interstripes) mounts an unbroken coverage of the visual field, since there is almost invariably some overlap between the aggregate fields recorded in successive stripes of the same class, at intervals of one cycle. Also as expected, penetrations perpendicular to the stripes record changes in eccentricity along an isopolar visual meridian. We measured the size of the point image along such an isopolar meridian in nine cases, and showed that on average it exceeds the length of a typical cycle;again, this implies that no point in space escapes analysis by any of the functional modules. The representation of eccentricity across a cycle of stripes resembles a "ratchet" model, in which the gradient of eccentricity across a single stripe exceeds the gradient across the full cycle, leading to discontinuities ("switchbacks") at the borders between stripes. The shift in eccentricity across the width of a stripe is sufficient to maintain a virtually continuous map across successive stripes of the same class: when coupled to receptive Field scatter about the mean trend, this creates the overlap of aggregate fields. The presence of topographic discontinuities, in addition to functional ones, at stripe boundaries, reflects autonomy of function at the local level. At a global level, however, the organization of V2 may promote integration across stripes, since the range of visual overlap, and intrinsic connections, exceeds a single cycle. Furthermore, the reduplication of modules along the isopolar axis has the effe

关键词： cytochrome oxidase stripes retinotopic mapping visual coverage "ratchet model" and "switchbacks" functional specialization functional integration

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coverage optimization of camera network for continuous deformable object

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MECHATRONICS 2023年第1期95卷

作者： Li, Chang Chen, Xi Chai, Li Wuhan Univ Sci & Technol Sch Informat Sci & Engn Wuhan 430081 Hubei Peoples R China Zhejiang Univ Coll Control Sci & Engn State Key Lab Ind Control Technol Hangzhou 310027 Zhejiang Peoples R China

In this paper, a deformable object is considered for camera network deployment with the aim of visual coverage. The object contour is discretized into sampled points as meshes, and the deformation is represented by continuous trajectories for the sampled points. To reduce the computational complexity, some feature points are carefully selected to represent the continuous deformation process. The visual coverage for the deformable object is transferred to cover the specific feature points. In particular, the vertexes of a rectangle that encloses the entire deformation trajectory of every sampled point on the object contour are chosen as the feature points. An improved wolf pack algorithm is then proposed to solve the optimization problem. Finally, both simulation and experimental results are given to demonstrate the effectiveness of the proposed deployment method of camera network.

关键词： Camera network deployment visual coverage Deformable object Wolf pack algorithm

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Same events, two stories: Comparing the photographic coverage of the 2008 anti-China/Olympics demonstrations in Chinese and US newspapers

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International Communication Gazette 2011年第8期73卷 732 - 752页

作者： Ying Huang Shahira Fahmy The University of West Florida USA The University of Arizona USA

A content analysis of photos from four major US newspapers and four major Chinese newspapers depicting the 2008 anti-China/Olympics protests revealed significantly different denoted themes. On one hand, the most prominent dominant visual theme in US newspapers was suppression followed by pro-Tibet demonstrations. On the other hand, in Chinese newspapers the most dominant visual theme was the Olympic torch relay followed by riots and restoring order. Overall, the US dailies visually portrayed a more pro-Tibetan independence slant and the Chinese dailies visually portrayed a more pro-Chinese government slant. Further, the US newspapers portrayed the anti-China demonstrators as non-violent while the Chinese newspapers portrayed them as violent. To give their readers a sense of harmony, Chinese dailies limited the number of images showing anti-China protests, while the US dailies highlighted them, communicating to their readers the suppressive nature of the Chinese government and downplaying the voices of people who supported it.

关键词： Chinese newspapers Olympics demonstrations US newspapers visual coverage

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AN OPTIMIZED PLACEMENT ALGORITHM FOR COLLABORATIVE INFORMATION PROCESSING AT A WIRELESS CAMERA NETWORK

AN OPTIMIZED PLACEMENT ALGORITHM FOR COLLABORATIVE INFORMATI...

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IEEE International Conference on Multimedia and Expo Workshops (ICMEW)

作者： Zhang, Hongguang Xia, Lingnan Tian, Fei Wang, Peng Cui, Jianzhu Tang, Chao Deng, Nana Ma, Na Chinese Acad Sci Shanghai Adv Res Inst Beijing 100864 Peoples R China shanghai key Lab Digital Media Process & Transmis Shanghai Peoples R China Chinese Acad Sci Shanghai Inst Microsyst & Informat Technol Beijing 100864 Peoples R China

ISBN: (纸本)9781479900152

The collaborative information processing is to identify, reconstruct and track targets collaboratively among multiple nodes which can complement each other for sensing capability, tolerate faults, and provide reliable decision. visual coverage and wireless connectivity are the most important two factors for collaborative information processing at a wireless camera network. This paper proposes a novel 3 Dimension (3D) surveillance model, which can solve the blind-area issue caused by the traditional 2D model. Furthermore, an optimal camera placement scheme is presented by using a binary integer programming algorithm on which the restraint of wireless connectivity is applied. Experimental results show that our method can effectively solve the problem of the blind-area issue, while satisfying the demand of the wireless connectivity.

关键词： Camera Placement visual coverage Wireless Connectivity 3D Surveillance Model

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In-Vehicle Camera Sensing: Hardware, Urban Applications and Research Trends 22

In-Vehicle Camera Sensing: Hardware, Urban Applications and ...

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IEEE 22nd Mediterranean Electrotechnical Conference (MELECON)

作者： Carvalho, Sara B. Costa, Daniel G. Univ Porto Fac Engn Porto Portugal Univ Porto Fac Engn SYSTEC ARISE Porto Portugal

ISBN: (纸本)9798350387032;9798350387025

Nowadays, camera technology is a common reality in the automobile industry, enabling functionalities that enhance the safety of vehicles and the understanding of the surrounding urban landscape. Such cameras can be integrated in various ways and for diverse purposes, paving the way for impressive transformation in mobility services. This paper delves into the vast realm of in-vehicle camera technology, tracing its evolution until the supporting of advanced driver assistance systems and as sources of important visual data of cities. We will examine different applications, including the presence of dashcams and the empowerment of self-driving cars through visual processing, unveiling the indispensable role of in-vehicle cameras for the evolving smart urban scenarios.

关键词： Embedded cameras Self-Driving Cars visual sensing visual coverage

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Picturing destruction at home and abroad: a comparative visual analysis of icons and news values during disaster

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MEDIA INTERNATIONAL AUSTRALIA 2021年第1期181卷 197-216页

作者： Thomson, Tj Queensland Univ Technol Kelvin Grove Qld Australia

This study uses news photographs and interviews with journalists to explore how Australia's unprecedented 2019-2020 bushfire season was depicted for Australian and non-Australian audiences in order to extend transnational understanding of iconicity's tenets and how news values vary across contexts. It does so first by examining the Sydney Morning Herald's coverage over 3 months and then by contrasting this with international coverage that began in early 2020 once the issue spilled onto the world stage. Australia's coverage focused intensely on human actors involved in the disaster while the vast numbers of affected animals were virtually absent. In contrast, international media visually depicted the disaster as an environmental and ecological issue with global consequences. The results suggest a need for a definition of iconicity that is inclusive to non-human actors and to inanimate forces that are personified. It also extends our cross-cultural understanding of the visual expression of news values.

关键词： Australian bushfires comparative media studies iconic imagery natural disaster coverage photojournalism press photography visual coverage visual journalism visual media visual news values

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Fotografie prezidentských kandidátů v českém tisku před prezidentskými volbami 2013

Fotografie prezidentských kandidátů v českém tisku pře...

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作者： Bednaříková, Barbora Charles University of Prague

Masters thesis Photographs of Presidential Candidates in Czech Newspapers ahead of Elections of 2013 compares the visual coverage of nine presidential candidates in the photographs published in three national broadsheet newspapers Lidové noviny, Právo and Hospodářské noviny during the period of four weeks before the first Czech direct presidential elections in January 2013. The theoretical part of the thesis summarizes literature probing the visual framing of politics and the influence of photographic images in media on audiences and their decisions in elections. The quantitative content analysis compares the number of each candidates pictures in the Czech press in order to determine whether the visual coverage was balanced or not and whether this could have affected the election results. It also verifies the hypothesis that newspapers tend to publish more pictures of the candidates with similar political orientation. Besides that, the thesis also compares how each of the journals uses photography illustration by examining the size, placement, type, caption length and authorship of the pictures.

关键词： Presidential election visual framing visual coverage portrait photography quantitative content analysis Miloš Zeman Karel Schwarzenberg

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Emerging Alternatives or Traditional News Gates: Which News Sources Were Used to Picture the 9/11 Attack and the Afghan War?

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International Communication Gazette 2005年第5期67卷 381 - 398页

作者： Shahira Fahmy

This study examines news sources used to visually portray the 11 September 2001 attack and the war in Afghanistan in the English-language newspaper The International Herald Tribune and the Arabic-language newspaper Al-Hayat. Differences were noted between news sources of images depicting the 9/11 attack and the Afghan War. However, despite these differences, the vast majority of photographs were from the main western news agencies: AP, AFP and Reuters. Results overall suggest, while there is no indication of changes in patterns of information flow, western news agencies provide a variety of news to be framed differently by different media.

关键词： 9/11 attack Afghan War framing news sources transnational media visual coverage

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