2,202 research outputs found
Wireless communication, identification and sensing technologies enabling integrated logistics: a study in the harbor environment
In the last decade, integrated logistics has become an important challenge in
the development of wireless communication, identification and sensing
technology, due to the growing complexity of logistics processes and the
increasing demand for adapting systems to new requirements. The advancement of
wireless technology provides a wide range of options for the maritime container
terminals. Electronic devices employed in container terminals reduce the manual
effort, facilitating timely information flow and enhancing control and quality
of service and decision made. In this paper, we examine the technology that can
be used to support integration in harbor's logistics. In the literature, most
systems have been developed to address specific needs of particular harbors,
but a systematic study is missing. The purpose is to provide an overview to the
reader about which technology of integrated logistics can be implemented and
what remains to be addressed in the future
On the Construction of Load-Balanced (k,r-hop)-Connected Dominating Set for WSNs
International audienceConnected Dominating Sets (CDS) are selected to construct a virtual backbone in Wireless Sensor Networks (WSNs). Indeed, CDS are used for fault tolerant broadcasting, routing and even efficient gathering of data. On the other hand, r-hop connected k-dominating sets ((k,r-hop)-CDS) are introduced to reduce the size of CDS and the total amount of information to be transmitted. Unfortunately, no work considers the load-balance factor of (k,r-hop)-CDS. Recently, there is a proposition of constructing load-balanced CDS for WSNs. In this paper we re-use the same concept of selecting load-balanced CDS to construct a Load-Balanced (k,r-hop)-CDS (LB(k,r-hop)-CDS). Then, the allocation of dominatees to the appropriate dominators is done. Through simulations, the proposed method of constructing LB(k,r-hop)-CDS extends network lifetime by an important rate compared with the most recent (k,r-hop)-CDS construction method
Smaller Connected Dominating Sets in Ad Hoc and Sensor Networks based on Coverage by Two-Hop Neighbors
In this paper, we focus on the construction of an efficient dominating set in ad hoc and sensor networks. A set of nodes is said to be dominating if each node is either itself dominant or neighbor of a dominant node. This set can for example be used for broadcasting, so the smaller the set is, the more efficient it is. As a basis for our work, we use a heuristics given by Dai and Wu for constructing such a set and propose an enhanced definition to obtain smaller sets. This approach, in conjunction with the elimination of message overhead by Stojmenovic, has been shown (in recent studies) to be an excellent compromise with respect to a wide range of metrics considered. In our new definition, a node u is not dominant if there exists in its 2-hop neighborhood a connected set of nodes with higher priorities that covers u and its 1-hop neighbors. This new rule uses the exact same level of information required by the original heuristics, only neighbors of nodes and neighbors of neighbors must be known to apply it, but it takes advantage of some knowledge originally not taken into account: 1-hop neighbors can be covered by some 2-hop neighbors. We give the proof that the set obtained with this new definition is a subset of the one obtained with Dai and Wu's heuristics. We also give the proof that our set is always dominating for any graph, and connected for any connected graph. Two versions were considered: with topological and positional information, which differ in whether or not nodes are aware of links between their 2-hop neighbors that are not 1-hop neighbors. An algorithm for applying the concept at each node is described. We finally provide experimental data that demonstrates the superiority of our rule in obtaining smaller dominating sets. A centralized algorithm was used as a benchmark in the comparison. The overhead of the size of connected dominating set was reduced by about 15% with the topological variant and by about 30% with the positional variant of our new definition
Public safety and cognitive radio
This book gives comprehensive and balanced coverage of the principles of cognitive radio communications, cognitive networks, and details of their implementation, including the latest developments in the standards and spectrum policy. Case studies, end-of-chapter questions, and descriptions of various platforms and test beds, together with sample code, give hands-on knowledge of how cognitive radio systems can be implemented in practice. Extensive treatment is given to several standards, including IEEE 802.22 for TV White Spaces and IEEE SCC41
Construction of Pipelined Strategic Connected Dominating Set for Mobile Ad Hoc Networks
Efficient routing between nodes is the most important challenge in a Mobile Ad Hoc Network (MANET). A Connected Dominating Set (CDS) acts as a virtual backbone for routing in a MANET. Hence, the construction of CDS based on the need and its application plays a vital role in the applications of MANET. The PipeLined Strategic CDS (PLS-CDS) is constructed based on strategy, dynamic diameter and transmission range. The strategy used for selecting the starting node is, any source node in the network, which has its entire destination within a virtual pipelined coverage, instead of the node with maximum connectivity. The other nodes are then selected based on density and velocity. The proposed CDS also utilizes the energy of the nodes in the network in an optimized manner. Simulation results showed that the proposed algorithm is better in terms of size of the CDS and average hop per path length
Recommended from our members
Adding the reliability on tree based topology construction algorithms for wireless sensor networks
Topology control is a technique used in wireless sensor networks to maximize energy efficiency and network lifetime. In previous literature, many tree based techniques have been proposed to save energy and increase the network lifetime. In tree based algorithms, the most promising solution is the formation of a network backbone, which serves on behalf of rest of the nodes in the network and therefore leading towards Connected Dominating Set (CDS) formulation. However, one imminent problem with all tree based solution is a compromise on network reliability. Therefore, to address reliability issues in tree based solutions, in this paper, we propose Poly3 which maintains cliques of size three in order to achieve network reliability on top of the CDS algorithm. This makes the network more robust to link removal. Our empirical and mathematical analysis reveals that Poly3 provides better reliability than algorithms of the same kind
- …