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Bandwidth-aware Breach-free Barrier Construction with VANET nodes for Realtime Fugitive Search
"... Abstract—In this paper, we introduce a new strategy of using VANET nodes with visual sensors and wireless transceivers to build an instant camera barrier for a given mission period. Given a set of properly equipped VANET nodes whose drivers voluntarily join the protocol by exposing their future trav ..."
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Abstract—In this paper, we introduce a new strategy of using VANET nodes with visual sensors and wireless transceivers to build an instant camera barrier for a given mission period. Given a set of properly equipped VANET nodes whose drivers voluntarily join the protocol by exposing their future travel plans and use onboard equipment to transmit realtime video to the authority, we aim to maintain the barrier of VANET nodes during a given mission period. Under the constraints that the mobility of each VANET node is not controllable and the size of barrier, i.e. the number of concurrent participants, cannot exceed a given number due to the network system capacity limit, we propose a polynomial time algorithm for the problem. To the best of our knowledge, this is the first work to consider the construction of camera barriers in pure mobile camera sensor network. Index Terms—Sensor barrier, sensor networking, VANET, barrier breach, scheduling. I.
Constructing Belt-barrier Providing -Quality of Monitoring with Minimum Camera Sensors
"... Abstract—A wireless sensor network is said to form a belt-barrier for a region if it is able to detect any object moving from outside the region to inside. Recently, Cheng and Tsai found if camera sensors are used to form a belt-barrier, the breadth of the barrier becomes an important quality factor ..."
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Abstract—A wireless sensor network is said to form a belt-barrier for a region if it is able to detect any object moving from outside the region to inside. Recently, Cheng and Tsai found if camera sensors are used to form a belt-barrier, the breadth of the barrier becomes an important quality factor to ensure high quality of monitoring (QoM). Then, they proposed the minimum-breadth belt-barrier construction problem ( (, 1)-B3CP) whose goal is to select a minimum number of camera sensors to form a-breadth belt-barrier, which ensures the width of the picture of any object which moves through the barrier is at least . In this paper, we perform more thorough investigation of the problem and introduce a new polynomial time exact algorithm for the problem under the assumption that the angle of each camera is fixed. Our simulation result shows our algorithm outperforms Cheng and Tsai’s algorithm. We also introduce a variation of (, 1)-B3CP, namely (; k)-B3CP, which aims to construct k node-disjoint-breadth belt-barrier for fault-tolerance purpose, propose a new heuristic algorithm for it, and conduct simulations to evaluate its performance. Index Terms—Wireless sensor network, camera sensor net-work, exact algorithm, graph theory, quality of monitoring. I.
Barrier-coverage for City Block Monitoring in Bandwidth Sensitive Vehicular Adhoc Networks
"... Abstract—Recently, vehicular ad hoc network (VANET) is receiving lots of attentions as this new networking technology is expected to improve our daily driving experience greatly and will enable a number of emerging applications. It is envisioned that the vehicles in VANETs are armed with a number of ..."
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Abstract—Recently, vehicular ad hoc network (VANET) is receiving lots of attentions as this new networking technology is expected to improve our daily driving experience greatly and will enable a number of emerging applications. It is envisioned that the vehicles in VANETs are armed with a number of advanced technologies such as wireless transceiver, video cameras, etc. This paper investigates the potential of the advanced VANET nodes to construct an impromptu surveillance system to surround an area of interest, which can be a city block, such that any suspect of interest leaving the city block can be monitored by a VANET node participating the surveillance system. Such a system can be useful to provide an emergency response system to keep the track of suspects who are leaving the area by walk or by car after committing a crime inside the block, e.g. Boston bombing suspects. We observe that as the network bandwidth is limited, not all vehicles can participate and transmit video to the control center in real time. Therefore, we propose new scheduling algorithms for the VANET nodes, which consider the mobility of each vehicle as well as the network bandwidth and continuously provides barrier-coverage circumventing the city block over a given mission period. Via simulation, we show the efficiency of our algorithms. I.
Critical Density for Coverage and Connectivity in Two-Dimensional Fixed-Orientation Directional Sensor Networks Using Continuum Percolation
"... Abstract: Given an initially uncovered field, and as more and more directional sensors (sensors with sector shape sensing area) are continuously added to the sensor network, the size of partial covered areas increases. At some point, the situation abruptly changes from small fragmented covered areas ..."
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Abstract: Given an initially uncovered field, and as more and more directional sensors (sensors with sector shape sensing area) are continuously added to the sensor network, the size of partial covered areas increases. At some point, the situation abruptly changes from small fragmented covered areas to a single large covered area. This abrupt change is called the sensing-coverage phase transition (SCPT). Likewise, given an originally disconnected sensor network, as more and more sensors are added, the number of connected components changes such that the sensor network suddenly becomes connected. This sudden change is called the network connectivity phase transition (NCPT). Such phase transitions occur in a certain density which is called critical density and finding it is a central topic of Percolation Theory. In this paper, we introduce fixed-orientation directional sensor networks (FIODSNs) and analytically compute critical density of nodes for both SCPT and NCPT in FIODSNs, for all field-of-view angles between
Vehicle Witnesses as a Service: Leveraging Vehicles as Witnesses on the Road in VANET Clouds
"... Abstract—Inspired by the dramatic evolution of VANET-clouds, this paper proposes a new VANET-cloud service called VWaaS (Vehicle Witnesses as a Service) in which vehicles moving on the road serve as anonymous witnesses of designated events such as a terrorist attack or a deadly accident. When confro ..."
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Abstract—Inspired by the dramatic evolution of VANET-clouds, this paper proposes a new VANET-cloud service called VWaaS (Vehicle Witnesses as a Service) in which vehicles moving on the road serve as anonymous witnesses of designated events such as a terrorist attack or a deadly accident. When confronted the events, a group of vehicles with mounted cameras collaborate with roadside stationary cameras to take pictures of the site of interest (SoI) around them, and send the pictures to the cloud infrastructure anonymously. The pictures are sent to the cloud in a way that the privacy of the senders can be protected, and kept by the cloud for future investigation. However, for the case that the pictures are used as an evidence of court trial, we made the privacy protection to be conditional and thus can be revoked by authorized entity(s) if necessary.
Digital Object Identifier 10.1109/ACCESS.2013.2282613 Wireless Video Surveillance: A Survey
"... the video capture and preprocessing; 2) the video compression and transmission in wireless sensor networks; and 3) the video analysis at the receiving end. A myriad of research works have been dedicated to this field due to its increasing popularity in surveillance applications. This survey provides ..."
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the video capture and preprocessing; 2) the video compression and transmission in wireless sensor networks; and 3) the video analysis at the receiving end. A myriad of research works have been dedicated to this field due to its increasing popularity in surveillance applications. This survey provides a comprehensive overview of existing state-of-the-art technologies developed for wireless video surveillance, based on the in-depth anal-ysis of the requirements and challenges in current systems. Specifically, the physical network infrastructure for video transmission over wireless channel is analyzed. The representative technologies for video capture and preliminary vision tasks are summarized. For video compression and transmission over the wireless networks, the ultimate goal is to maximize the received video quality under the resource limitation. This is also the main focus of this survey. We classify different schemes into categories including unequal error protection, error resilience, scalable video coding, distributed video coding, and cross-layer control. Cross-layer control proves to be a desirable measure for system-level optimal resource allocation. At the receiver’s end, the received video is further processed for higher-level vision tasks, and the security and privacy issues in surveillance applications are also discussed. INDEX TERMS Video surveillance, wireless sensor networks, multimedia communications, cross-layer control, video analysis. I.
Deploying Sensors for Gravity Measurement in a Body-Area Inertial Sensor Network
"... Abstract — This paper deals with human posture tracking by deploying accelerometers on a human body. One fundamental issue in such scenarios is how to calculate the gravity. This is very challenging especially when the human body parts keep on moving. Fortunately, it is likely that there is a point ..."
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Abstract — This paper deals with human posture tracking by deploying accelerometers on a human body. One fundamental issue in such scenarios is how to calculate the gravity. This is very challenging especially when the human body parts keep on moving. Fortunately, it is likely that there is a point of the body that touches the ground in most cases. This allows sensors to collaboratively calculate the gravity vector. Assuming multiple accelerometers being deployed on a rigid part of a human body, a recent work proposes a data fusion method to estimate the gravity vector on that rigid part. However, finding the optimal deployment of sensors that minimizes the estimation error of the gravity vector is not addressed. In this paper, we formulate the deployment optimization problem and propose two heuristics, called Metropolis-based method and largest-inter-distance-based method. Simulation and real experimental results show that our schemes are quite effective in finding near-optimal solutions for a variety of rigid body geometries. Index Terms — Accelerometer, deployment optimization, modeling of systems and physical environments, wireless sensor network. I.
