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Development of Internet of things (IoT) applications brings a new movement to the functionality of wireless sensor networks (WSNs) from only environment sensing and data gathering to collaborative inferring and ubiquitous intelligence. In intelligent WSNs, nodes collaborate to exchange the information needed to achieve the required inference or smartness. Efficiency or correctness of many smart applications rely on efficient, timely, reliable, and ubiquitous inference of information which may continually change in interaction with other nodes. In this paper, we introduce a framework which provides a generic solution for such common ubiquitous inferences. This framework brings the reliability... 

This paper presents a centralized fault detection algorithm for wireless sensor networks. Faulty sensor nodes are identified based on comparisons between neighboring nodes and own central node and dissemination of the decision made at each node. RNS system is used to tolerate transient faults in sensing and communication. In this system, arithmetic operations act on residues - reminder of dividing original number in several definite modules - in parallel. Consequently computations on these residues which are smaller than the original number are performed, so speed up arithmetic and decreased power consumption is achieved. ©2009 IEEE  

Wireless Sensor Network (WSN) should be capable of fulfilling its mission, in a timely manner and without loss of important information. In this paper, we propose a new analytical model for calculating RRT (Reliable Real-Time) degree in multihop WSNs, where RRT degree describes the percentage of real-time data that the network can reliably deliver on time from any source to its destination. Also, packet loss probability is modeled as a function of the probability of link failure when the buffer is full and the probability of node failure when node's energy is depleted. Most of network properties are considered as random variables and a queuing-theory based model is derived. In this model,... 

The accuracy of the object tracking is dependent on the tracking time interval. Smaller tracking time interval increases the accuracy of tracking a moving object. However, this increases the power consumption significantly. This paper proposes a new adaptive algorithm (AEC) to adapt tracking time interval such that it minimizes power consumption while keeping the required accuracy. Simulation results show that using the proposed algorithm, the tracking network has a good performance with the added advantage of reducing the power consumption significantly when compared with existing nonadaptive methods (like PATES). Moreover, simulation results show that the performance of the proposed... 

Energy distribution to get more lifetime and noninterfering multipath are two major challenges in Wireless Multimedia Sensor Networks (WMSNs) routing. The Greedy Perimeter Stateless Routing (GPSR) is a simple routing protocol which uses minimum geographic distance to forward packets toward sink node. However it does not consider energy level and uses single path. Geographic energy-aware non-interfering multipath Routing (GEAM) overcomes this problem by multipath routing and energy consideration, but keeping state of the multiple non-interfering areas has an overhead. In our proposed routing protocol which is called Energy Aware Greedy Stateless Geographic Routing (EAGSGR) we will introduce... 

Matrix sensing refers to recovering a low-rank matrix from a few linear combinations of its entries. This problem naturally arises in many applications including recommendation systems, collaborative filtering, seismic data interpolation and wireless sensor networks. Recently, in these applications, it has been noted that exploiting additional subspace information might yield significant improvements in practical scenarios. This information is reflected by two subspaces forming angles with column and row spaces of the ground-truth matrix. Despite the importance of exploiting this information, there is limited theoretical guarantee for this feature. In this work, we aim to address this issue... 

Nowadays, wireless sensor networks are known as a new challenge in network science. New features of these networks have made it impossible to use the traditional routing protocols. The most important challenge of these networks is the limited energy of nodes. In this paper, we will introduce MEHR as a multi-hop location-unaware hierarchical routing protocol to decrease the energy consumption in nodes, and to increase the network lifetime, we also apply MEHR to reach to a scalable routing. We will introduce a new factor to select candidate nodes and to send intra-cluster messages. We will use place-advertisement messages of sink, and a limiting parameter and also overhearing concept to create... 

A set of small battery-operated sensors with low-power transceivers that can automatically form a network and collect some desired physical characteristics of the environment is called a wireless sensor network. The communications must be designed to conserve the limited energy resources of the sensors [14].By clustering sensors we can save energy. In this paper, we introduce a new concept called "Center of Energy Mass" which is a combination of both energy level and location of the nodes which is used to form the new factor of "distance of the nodes to the CEM ".Distance of the nodes to the CEM is used together with Probability Density Function of the normal distribution in optimizing... 

Network survivability is one of the main design challenges in wireless sensor networks (WSN). Survivability is the ability of the network to provide essential services in the presence of attacks and/or failures, and recover full service in a timely manner. To the best knowledge of us, survivability for WSN has never been studied considering failure effects on network. We consider the network survivability as a composite measure consisting of both network failure duration and failure impact on the network. In this paper we model network survivability in steady state. In this state, network is affected by predicted failures. This modeling is based on network connectivity and coverage, when an... 

We study a constrained version of the shortest path problem in polygonal domains, in which the path must visit a given target polygon. We provide an efficient algorithm for this problem based on the wavefront propagation method and also present a method to construct a subdivision of the domain to efficiently answer queries to retrieve the constrained shortest paths from a single-source to the query point. © 2008 Springer-Verlag Berlin Heidelberg  

This paper introduces an analytical method for approximating the performance of a two-class priority M/M/1 system. The prioritized class-1 jobs are real-time, served either with the preemptive or non-preemptive Earliest- Deadline- First (EDF) policy and can preempt the non real-time class-2 jobs. The preempted service of the class-2 job is resumed from the time in instances where no class-1 job is in the system. The service discipline of class-2 jobs is FCFS. The required mean service times may depend on the class of the jobs. The real-time jobs have exponentially distributed relative deadlines until the end of service. The system is approximated by a Markovian model in the long run, which... 

Wireless Sensor Network (WSN) should be capable of fulfilling its mission, in a timely manner. Therefore, we propose a quantitative real-time model for multihop WSN. "Real-time degree" describes the percentage of real-time data that the network can deliver on time from any source to its destination. Most of network properties are considered as random variables and a queuing-theory based model is derived. In this model, the effect of network load on the packets ' delay and the "real-timeliness" of the network are considered. Simulation results are used to validate the proposed model. The simulation results agree very well with the model. © 2007 IEEE  

Localization of an emitting or reflecting target is one of the most important issues in a wide range of applications including radar, sonar, wireless communication and sensor networks. Due to significant effect on the positioning accuracy, designing the optimal sensor-target geometry has been considered as an important problem in the localization literature. The existing sensor placement methods mainly solve the problem in the cases without any constraints on the sensors locations. In the realistic scenarios, however, the sensors cannot be placed simply in arbitrary locations due to such constraints as the geographical limitations, communication problems between the sensor pairs and the... 

In this paper, a new method is proposed utilizing a diversity scheme to reduce power consumption in large scale sensor networks. Sensor networks are composed of large number of battery powered nodes. Energy consumption is the most important design objective in sensor networks while delay and throughput are taken less into account. Wireless transmission is the other important characteristic of these networks. Small-scale fading decreases wireless communication performance. In a fading channel higher SNRs is needed and consequently more energy is consumed in fading channels. Another important characteristic of sensor networks is the necessity of fault tolerant protocols. Node-to-node links are... 

In this paper a modified neighbor aware medium-access control protocol is proposed designed for wireless sensor networks. Wireless sensor networks are generally comprised of battery powered nodes. These nodes are densely deployed in an ad-hoc structure. The main objective for sensor networks is low power consumption while latency is less important. This leads different MAC layer design for wireless sensor networks compared to conventional ad hoc protocols. In this paper we propose a neighbor aware medium access control to reduce power consumption. This protocol is derived from Modified Distributed mediation device (MDMD) protocol and uses useful properties of this protocol while improves the... 

The wide range of wireless sensor network applications has made it an interesting subject for many studies. One area of research is the controlled node placement in which the location of nodes is not random but predetermined. Controlled node placement can be very effective when either the price of the sensor nodes is high or the sensor coverage is of a specific type and it is necessary to provide special characteristics such as coverage, lifetime, reliability, delay, efficiency or other performance aspects of a wireless sensor network by using the minimum number of nodes. Since node placement algorithms are NP-Hard problems, and characteristics of a network are often in conflict with each... 

The emerging multimedia applications of Wireless Sensor Network (WSNs) impose new challenges in design of algorithms and communication protocols for such networks. In the view of these challenges, error control is an important mechanism that enables us to provide robust multimedia communication and maintain Quality of Service (QoS). Despite the existence of some good research works on error control analysis in WSNs, none of them provides a thorough study of error control schemes for multimedia delivery. In this paper, a comprehensive performance evaluation of Automatic Repeat Request (ARQ), Forward Error Correction (FEC), Erasure Coding (EC), link-layer hybrid FEC/ARQ, and cross-layer hybrid... 

Ease of use, high flexibility and variety of applications have made wireless sensor networks very popular. Node placement in a sensor network is very critical since it affects important network attributes such as coverage, lifetime, and reliability. Therefore, controlled node placement is necessary for achieving specific network features with minimum number of nodes. Since node placement is an NP-hard problem, many placement algorithms have been proposed based on heuristic and meta-heuristic methods. Most of those algorithms assume a uniform event pattern (UEP) throughout the area under investigation. However, in practice some networks deal with non-uniform event pattern (NEP). Optimization... 

In wireless sensor networks (WSN), individual sensor nodes are inherently unreliable and have very limited capabilities to ensure real-time properties. In fact, one of the most predominant limitations in wireless sensor networks is energy consumption, which hinders the capacity of the network to provide real-time guarantees (e.g. low duty-cycles, low transmission range). Many approaches have been proposed to deal with energy/latency trade-offs, but they are likely to be insufficient for the applications where reduced delay guarantee is the main concern. We present and evaluate a packet scheduling policy and routing algorithm called RACE that inherently accounts for time constraints. We show...