One fundamental issue in sensor networks is the coverage problem, which reflects how well a network monitored or tracked by sensors. In this paper, we formulate problem as decision whose goal to determine whether every point service area of covered at least k sensors, where predefined value. The sensing ranges sensors can be unit disks non-unit disks. We present polynomial-time algorithms, terms number that easily translated distributed protocols. result generalization some earlier results...

In a multihop mobile ad hoc network, broadcasting is an elementary operation to support many applications. Previously, it shown that naively by flooding may cause serious redundancy, contention, and collision in the which we refer as broadcast storm problem. Several threshold-based schemes are perform better than work. However, how choose thresholds also poses dilemma between reachability efficiency under different host densities. this paper, propose several adaptive schemes, can dynamically...

In mobile ad hoc networks (MANETs), one essential issue is how to increase channel utilization while avoiding the hidden-terminal and exposed-terminal problems. Several MAC protocols, such as RTS/CTS-based busy-tone-based schemes, have been proposed alleviate these this paper, we explore possibility of combining concept power control with protocols further utilization. A sender will use an appropriate level transmit its packets so reuse. The using discrete, instead continuous, levels also...

Power-saving is a critical issue for almost all kinds of portable devices. In this paper, we consider the design power-saving protocols mobile ad hoc networks (MANETs) that allow hosts to switch low-power sleep mode. The MANETs being considered in paper are characterized by unpredictable mobility, multi-hop communication, and no clock synchronization mechanism. particular, last characteristic would complicate problem since host has predict when another will wake up receive packets. We...

The rapid progress of wireless communication and embedded microsensing MEMS technologies has made sensor networks possible. In light storage in sensors, a network can be considered as distributed database, which one conduct in-network data processing. An important issue is object tracking, typically involves two basic operations: update query. This been intensively studied other areas, such cellular networks. However, the processing characteristic posed new challenges to this issue. paper,...

This letter presents a novel steganography scheme capable of concealing piece critical information in host message which is binary image (e.g., facsimile). A matrix and weight are used as secret keys to protect the hidden information. Given size m/spl times/n, proposed can conceal many /spl lfloor/log/sub 2/ (mn+1)/spl rfloor/ bits data by changing, at most, two image. provide higher security, embed more information, maintain quality than available schemes.

Sensor deployment is a critical issue because it affects the cost and detection capability of wireless sensor network. In this work, we consider two related problems: placement dispatch. The former asks how to place least number sensors in field achieve sensing coverage network connectivity, latter determine from set mobile subset be moved an area interest with certain objective functions such that connectivity properties are satisfied. This work targeted toward planned deployment. Our...

One of the research issues in wireless sensor networks (WSNs) is how to efficiently deploy sensors cover an area. In this paper, we solve k-coverage deployment problem achieve multi-level coverage area I. We consider two sub-problems: placement and distributed dispatch problems. The asks determine minimum number required their locations I guarantee that k-covered network connected; schedule mobile move designated according result computed by strategy such energy consumption due movement...

Recently, wireless sensor networks (WSNs) have been widely discussed in many applications. In this paper, we propose a WSN-based intelligent light control system for indoor environments. Wireless sensors are responsible measuring current illuminations. Two kinds of lighting devices, namely, whole and local used to provide background concentrated illuminations, respectively. Users may various illumination requirements according their activities profiles. An requirement is as the combination...

Incorporating the environment-sensing capability of wireless sensor networks into video- based surveillance systems can provide advanced services at a lower cost than traditional systems.The integrated mobile and system (iMouse) uses static sensors to detect then analyze unusual events in environment.

Wireless sensor networks have attracted a lot of attention recently. Such environments may consist many inexpensive nodes, each capable collecting, storing, and processing environmental information, communicating with neighboring nodes through wireless links. For network to operate successfully, sensors must maintain both sensing coverage connectivity. This issue has been studied in wang et al. [2003] Zhang Hou [2004a], which reach similar conclusion that can imply connectivity as long...

With the design of data communications in mind, 3GPP LTE-advanced (LTE-A) is probably most promising technology for Internet Things (IoT). For IoT applications, continuous low-rate streaming may be reported from devices over a long period time, imposing stringent requirements on power saving. To manage consumption, LTE-A has defined discontinuous reception/transmission (DRX/DTX) mechanism to allow turn off their radio interfaces and go sleep various patterns. Existing literature paid much...

Recently, wireless sensor networks have attracted a lot of attention. Such environments may consist many inexpensive nodes, each capable collecting, storing, and processing environmental information, communicating with neighboring nodes through links. In this paper, we survey fundamental problem in networks, the coverage problem, which reflects how well an area is monitored or tracked by sensors. We first study several relevant computational geometric problems. Then, number papers aimed at...

One of the fundamental issues in sensor networks is coverage problem, which reflects how well a network monitored or tracked by sensors. In this paper, we formulate problem as decision whose goal to determine whether every point service area covered at least /spl alpha/ sensors, where given parameter and sensing regions sensors are modeled balls (not necessarily same radius). This 2D space solved (C. F. Huang et al, ACM Int'l W'kshop on Wireless Sensor Networks App., p.115-12 1, 2003) with...

In a mobile ad-hoc networks (MANET), one essential issue is medium access control (MAC) which addresses how to utilize the radio spectrum efficiently and resolve potential contention collision among hosts on using medium. Existing work dedicated multiple channels power improve performance of MANET. We investigate possibility bringing concepts multi-channel together in MAC design problem protocols only address these issues independently. The proposed protocol characterized by following...

In recent years, the wireless mesh network (WMN) attracts interest of many people as a new broadband Internet access technology. However, increasing throughput is still an open and challenging research issue. One potential solution to enable transceivers utilize multiple channels dynamically. most existing works do not consider routing issue, trivially use some popular single-path protocols like AODV DSR. this paper, we exploit benefit multi-path in multi-channel WMNs from aspect end-to-end...

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> Recently, wireless sensor and actuator networks (WSANs) have been widely discussed in many applications. In this paper, we propose an autonomous light control system based on the feedback from sensors carried by users. Our design focuses meeting users' preferences energy efficiency. Both whole local lighting devices are considered. Users' may depend their activities profiles two requirement...