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Article

Leping Huang, Hongyuan Chen, T.V.L.N. Sivakumar, Tsuyoshi Kashima and Kaoru Sezaki

To utilize Bluetooth as a layer 2 multi‐hop subnet for global IP network, there are two missing protocols in current Bluetooth stack: network formation and routing. In…

Abstract

To utilize Bluetooth as a layer 2 multi‐hop subnet for global IP network, there are two missing protocols in current Bluetooth stack: network formation and routing. In this paper, we propose our network formation and routing protocols optimized for such Bluetooth subnset usage scenarios to fill this gap. In this paper, we first present some observations on performance degradations of Bluetooth PAN due to network topologies and topology change when radio independant protocols are implemented. And then we analyze the reason of performance degradation. Based on our analysis, we first propose a flexible scatternet formation algorithm under conference scenario for multi‐hop communication. By using proposed method, scatternet can be formed flexibly with star, mesh, or linked line based on several parameters like number of maximum piconets that a gateway Bluetooth device can participate, and whether loops are needed in the resulting scatternet to achieve better network performance. To utilize topology information in multi‐hop communication, we propose a Cross‐layer Optimized Routing for Bluetooth (CORB) CORB is a QoS‐extended AODV routing protocol with mainly two optimizations between networking layer and underlying Bluetooth MAC layer. The first optimization is to use a new load metric. (LM) in QoS routing protocol instead of number of hops in conventional best effort routing. LM is derived from estimation of nodes’ link bandwidth, which reflects the different roles of nodes in Bluetooth scatternet. This proposal helps routing protocol to bypass heavily loaded nodes, and find route with larger bandwidth. The second optimization is to adjust LM and some MAC layer parameters in response to the unstable network topology caused by movement and change of indoor radio condition. Finally, We present some simulation and experiment results based on implementation, which prove the effectiveness of our protocols.

Details

International Journal of Pervasive Computing and Communications, vol. 1 no. 2
Type: Research Article
ISSN: 1742-7371

Keywords

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Article

D. K. Rawal, Mangey Ram and V. V. Singh

– The purpose of this paper is to find the reliability measures of Linux operating system connected in local area network (LAN).

Abstract

Purpose

The purpose of this paper is to find the reliability measures of Linux operating system connected in local area network (LAN).

Design/methodology/approach

The system has two different topologies, i.e. star topology (subsystem-1) and bus topology (subsystem-2), are placed at two different places, and connected to a server through a hub. Both the topologies have n clients. The system has partial failure and complete failure. The partial failure is of two type’s namely minor partial and major partial. The minor partial failure degrades the system whereas the major partial failure brings the system to a break down mode. The system can completely fail due to failure of server hacking and blocking.

Findings

By using supplementary variable technique and Laplace transformation, by taking different types of failure and two types of repairs the availability, non-availability, mean time to failure and cost analysis (expected profit) of the design system have been obtained.

Originality/value

In this research, a mathematical model of Linux operating system has been discussed from which one can check the behavioral analysis of the designed system.

Details

International Journal of Quality & Reliability Management, vol. 32 no. 1
Type: Research Article
ISSN: 0265-671X

Keywords

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Article

Boris Mitavskiy, Jonathan Rowe and Chris Cannings

A variety of phenomena such as world wide web, social or business networks, interactions are modelled by various kinds of networks (such as the scale free or preferential…

Abstract

Purpose

A variety of phenomena such as world wide web, social or business networks, interactions are modelled by various kinds of networks (such as the scale free or preferential attachment networks). However, due to the model‐specific requirements one may want to rewire the network to optimize the communication among the various nodes while not overloading the number of channels (i.e. preserving the number of edges). The purpose of this paper is to present a formal framework for this problem and to examine a family of local search strategies to cope with it.

Design/methodology/approach

This is mostly theoretical work. The authors use rigorous mathematical framework to set‐up the model and then we prove some interesting theorems about it which pertain to various local search algorithms that work by rerouting the network.

Findings

This paper proves that in cases when every pair of nodes is sampled with non‐zero probability then the algorithm is ergodic in the sense that it samples every possible network on the specified set of nodes and having a specified number of edges with nonzero probability. Incidentally, the ergodicity result led to the construction of a class of algorithms for sampling graphs with a specified number of edges over a specified set of nodes uniformly at random and opened some other challenging and important questions for future considerations.

Originality/value

The measure‐theoretic framework presented in the current paper is original and rather general. It allows one to obtain new points of view on the problem.

Details

International Journal of Intelligent Computing and Cybernetics, vol. 2 no. 2
Type: Research Article
ISSN: 1756-378X

Keywords

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Article

V. V. Singh, Abubakkar Idris Mohhammad, Kabiru Hamisu Ibrahim and Ibrahim Yusuf

This paper analyzed a complex system consisting n-identical units under a k-out-of-n: G; configuration via a new method which has not been studied by previous researchers…

Abstract

Purpose

This paper analyzed a complex system consisting n-identical units under a k-out-of-n: G; configuration via a new method which has not been studied by previous researchers. The computed results are more supportable for repairable system performability analysis.

Design/methodology/approach

In this paper, the authors have analyzed a complex system consisting n-identical units under a k-out-of-n: G; configuration via a new method which has not been studied by previous researchers. The supplementary variable technique has employed for analyzing the performance of the system.

Findings

Reliability measures have been computed for different types of configuration. It generalized the results for purely series and purely parallel configurations.

Research limitations/implications

This research may be beneficial for industrial system performances whereas a k-out-of-n-type configuration exists.

Practical implications

Not sure as it is a theoretical assessment.

Social implications

This research may not have social implications.

Originality/value

This work is the sole work of authors that have not been communicated to any other journal before.

Details

International Journal of Quality & Reliability Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0265-671X

Keywords

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Article

Lixuan Lu and Jianhe Lei

Proper function of landing gear plays a crucial role in the safe operation of an airplane. Traditional landing gear control system utilizes centralized control technology…

Abstract

Purpose

Proper function of landing gear plays a crucial role in the safe operation of an airplane. Traditional landing gear control system utilizes centralized control technology. The relatively heavy wire harness and low reliability accompanied with this technology make it logical to transfer from traditional control to real‐time distributed control. This paper aims to look into a new landing gear control system based on time‐triggered architecture (TTA).

Design/methodology/approach

In this paper, a new landing gear control system based on TTA is proposed. The reliability of the proposed system is investigated using a combination of Markov analysis and MIL‐HDBK‐217 methods.

Findings

The results show that by integration of TTP/C and TTP/A technologies, the advantages of both are achieved. A very high level of reliability is obtained. This increases the confidence when adopting distributed landing gear control technology.

Originality/value

The paper presents a new landing gear control system based on TTA, the reliability of which is very high.

Details

Aircraft Engineering and Aerospace Technology, vol. 82 no. 1
Type: Research Article
ISSN: 0002-2667

Keywords

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Article

Mohammed M. Aman, Wilfred W. Fong and Virgil Diodato

A local area network (LAN) connects computers, printers, modems and other devices located near each other, often in an office environment. The School of Library and…

Abstract

A local area network (LAN) connects computers, printers, modems and other devices located near each other, often in an office environment. The School of Library and Information Science (SLIS) at the University of Wisconsin‐Milwaukee provides a case study of selecting and using a LAN in an academic program environment. Consideration of various types of LANs took place during the selection of a LAN for SLIS. The advantages of having a LAN at SLIS have been the sharing of printers and other devices, the use of electronic mail, improvement in office management and cooperative research, and easier access to information and files available in the school.

Details

The Electronic Library, vol. 8 no. 4
Type: Research Article
ISSN: 0264-0473

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Article

Nai‐Luen Lai, Chun‐Han Lin and Chung‐Ta King

A primary task of wireless sensor networks is to measure environmental conditions. In most applications, a sink node is responsible for collecting data from the sensors…

Abstract

Purpose

A primary task of wireless sensor networks is to measure environmental conditions. In most applications, a sink node is responsible for collecting data from the sensors through multihop communications. The communication pattern is called convergecast. However, radio congestion around the sink can easily become a bottleneck for the convergecast. The purpose of this paper is to consider both scheduling algorithms and routing structures to improve the throughput of convergecast.

Design/methodology/approach

The paper addresses the issue from two perspectives. First by considering the transition scheduling that reduces radio interference to perform convergecast efficiently. Second, by studying the effects of routing structures on convergecast. A routing algorithm, called disjoint‐strip routing, is proposed as an alternative to existing shortest‐path routing.

Findings

The paper shows that constructing a shortest‐length conflict‐free schedule is equivalent to finding a minimal vertex coloring. To solve the scheduling problem, a virtual‐node expansion is proposed to handle relay operations and then coloring algorithms are utilized. Regarding the routing structures, a disjoint‐strip algorithm is proposed to leverage possible parallel transmissions. Proposed algorithms are evaluated through simulations.

Originality/value

This paper separates the problem for optimizing data‐collection throughput into two stages: constructing a routing structure on a given deployment; and scheduling the activation time of each link. Determining routing topologies and communication schedules for optimal throughput are shown to be hard, so heuristics are applied in both stages. VNE is proposed, which makes traffic information visible to coloring algorithms. The advantage of VNE is verified through simulations. VNE can be applied to any coloring algorithm and any deterministic traffic pattern. It is shown that routing structures set a limit on the performance of scheduling algorithms. There are two possible ways in routing algorithms to improve convergecast throughput: first, by reducing the total number of transmissions during data collection; second, by transferring data in parallel. The shortest‐path routing addresses the first point while DS addresses the second one. As expected, when the deployments are even and balanced, minimizing the number of transmissions is more effective than parallelizing them. On the other hand, when the deployments are unbalanced and conflicts are not strict, parallel transmissions can improve the throughput.

Details

International Journal of Pervasive Computing and Communications, vol. 6 no. 1
Type: Research Article
ISSN: 1742-7371

Keywords

Abstract

Details

Library Hi Tech News, vol. 18 no. 6
Type: Research Article
ISSN: 0741-9058

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Article

Bengi Aygün and Vehbi Cagri Gungor

The purpose of this paper is to provide a contemporary look at the current state‐of‐the‐art in wireless sensor networks (WSNs) for structure health monitoring (SHM…

Abstract

Purpose

The purpose of this paper is to provide a contemporary look at the current state‐of‐the‐art in wireless sensor networks (WSNs) for structure health monitoring (SHM) applications and discuss the still‐open research issues in this field and, hence, to make the decision‐making process more effective and direct.

Design/methodology/approach

This paper presents a comprehensive review of WSNs for SHM. It also introduces research challenges, opportunities, existing and potential applications. Network architecture and the state‐of‐the‐art wireless sensor communication technologies and standards are explained. Hardware and software of the existing systems are also clarified.

Findings

Existing applications and systems are presented along with their advantages and disadvantages. A comparison landscape and open research issues are also presented.

Originality/value

The paper presents a comprehensive and recent review of WSN systems for SHM applications along with open research issues.

Details

Sensor Review, vol. 31 no. 3
Type: Research Article
ISSN: 0260-2288

Keywords

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Article

Danilo Ferreira de Carvalho and Carmelo José Albanez Bastos‐Filho

Particle swarm optimization (PSO) has been used to solve many different types of optimization problems. In spite of this, the original version of PSO is not capable to…

Abstract

Purpose

Particle swarm optimization (PSO) has been used to solve many different types of optimization problems. In spite of this, the original version of PSO is not capable to find reasonable solutions for some types of problems. Therefore, novel approaches to deal with more sophisticated problems are required. Many variations of the basic PSO form have been explored, targeting the velocity update equation. Other approaches attempt to change the communication topology inside the swarm. The purpose of this paper is to propose a topology based on the concept of clans.

Design/methodology/approach

First of all, this paper presents a detailed description of its proposal. After that, it shows a graphical convergence analysis for the Rosenbrock benchmark function. In the sequence, a convergence analysis for clan PSO with different parameters is performed. A comparison with star, ring, focal, von Neumann and four clusters topologies is also performed.

Findings

The paper's simulation results have shown that the proposal obtained better results than the other topologies for the benchmark functions selected for this paper.

Originality/value

The proposed topology for PSO based on clans provides a novel form for information distribution inside the swarm. In this approach, the topology is determined dynamically during the search process, according to the success rate inside each clan.

Details

International Journal of Intelligent Computing and Cybernetics, vol. 2 no. 2
Type: Research Article
ISSN: 1756-378X

Keywords

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