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1 – 10 of 385
Article
Publication date: 14 July 2021

Sakshi Garg, Deepti Mehrotra, Sujata Pandey and Hari Mohan Pandey

This paper aims to determine the network efficient topology for low power and lossy networks (LLNs) using routing protocol for LLN (RPL) with respect to the increase in network…

Abstract

Purpose

This paper aims to determine the network efficient topology for low power and lossy networks (LLNs) using routing protocol for LLN (RPL) with respect to the increase in network size and propose a novel approach to overcome the shortcomings of the existing models.

Design/methodology/approach

The authors have used Contiki OS/Cooja simulator to conduct experiments on primarily four topologies (star, bus/linear, ring/eclipse and random). They have implemented RPL protocol using Sky motes for each topology from 10, 20, 30 and up to 70 nodes. Consequently, after 24 h of experimentation, the readings have been noted and, alongside, a comprehensive comparative analysis has been performed based on the network density and metric parameters: packet delivery ratio (PDR), expected transmission (ETX) and power consumption. Further, a hybrid model is proposed where the additional factors of mobility, multiple sink and a combination of static and mobile nodes are introduced. The proposed model is then compared with the star model (all static nodes and star topology) and the dynamic model (all mobile nodes) to analyze the efficiency and network performance for different network sizes (28, 36, 38 and 44 nodes). The mobility is introduced using BonnMotion tool in Contiki OS.

Findings

Simulation results have shown that the star topology is most network efficient when compared with bus/linear, ring/eclipse and random topologies for low density and high scalable network. But when the same setup is compared with the proposed hybrid model, the proposed model shows a significant improvement and gives the best and efficient network performance with highest PDR (average improvement approximately 44.5%) and lowest ETX (average improvement approximately 49.5%) comparatively.

Practical implications

Also, these findings will benefit the deployment of smart devices used in advanced metering infrastructure, road side units and in various industrial applications such as traffic monitoring system, electronic toll collection and traffic analysis in the smart grid infrastructure.

Originality/value

The impact of topology is significant and detailed analysis is required to understand the impact of different topologies of the nodes in the network for the present and the future scenarios. As very few research studies have discussed this gap, this research paper is quintessential and shall open novel future potential direction. Also, the proposed approach of hybrid model with mobility has not been considered in the literature yet.

Article
Publication date: 1 April 2000

Jian‐Guo Zhang, A.B. Sharma, Yu‐De Ni and Zheng Li

The design issues on network architecture and modulation scheme that can be used to implement reliable MIL‐STD‐1773 avionics optical fiber data buses are discussed. Both…

1281

Abstract

The design issues on network architecture and modulation scheme that can be used to implement reliable MIL‐STD‐1773 avionics optical fiber data buses are discussed. Both single‐star and multi‐star architectures are presented to such optical fiber data buses. Several network configurations based on passive and/or active coupling components are also considered, and they are compared in terms of system complexity and reliability. Moreover, three modulation schemes are presented, i.e. partial trilevel Manchester II bi‐phase coding, extended Manchester II bi‐phase coding with beginning‐stopping flags, and pseudo‐four‐ary pulse width modulation, respectively. Their use can feasibly solve the problem associated with fast identification of correct operation states of an active transmitter at the output of optical receivers.

Details

Aircraft Engineering and Aerospace Technology, vol. 72 no. 2
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 5 January 2015

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

Article
Publication date: 26 January 2010

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. The…

1092

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

Article
Publication date: 1 February 1988

Larry L. Learn

This article provides a broad overview of telecommunications and network‐related technologies. Topics covered include identification and review of network elements, analog and…

214

Abstract

This article provides a broad overview of telecommunications and network‐related technologies. Topics covered include identification and review of network elements, analog and digital signals, synchronous and asynchronous transmission formats, transmission media and equipment, transmission techniques and characteristics, multiplexing, network types, access technologies, network architectures and topologies, local‐area network technologies and attributes, protocols and protocol issues, gateways, internetworking, local networking alternatives, equipment certification, and various aspects of network management. It is intended to provide the practicing professional in the field of library and information science with a broad, up‐to‐date technical review that might serve to support and facilitate further investigation of current developments in networks and networking. Although the broad range of topics is not treated in depth, numerous references are provided for further investigation.

Details

Library Hi Tech, vol. 6 no. 2
Type: Research Article
ISSN: 0737-8831

Article
Publication date: 1 March 1994

Avi Rushinek and Sara F. Rushinek

Suggests that, though local area networking is one of the fastestgrowing segments in the computer industry, the selection of appropriatefeatures for inclusion in local area…

1173

Abstract

Suggests that, though local area networking is one of the fastest growing segments in the computer industry, the selection of appropriate features for inclusion in local area networks (LANs) can be confusing for both vendors and end‐users. Describes a system that measures the degree to which specific LAN features meet end‐user needs and contribute to profitability. Reveals that, in the analysis, the features file security and remote access had positive effects on the overall LAN price. Provides a methodology for selecting the most profitable features, such as remote access and gateways to PC networks, to include in a contemplated LAN product line.

Details

Industrial Management & Data Systems, vol. 94 no. 2
Type: Research Article
ISSN: 0263-5577

Keywords

Article
Publication date: 1 August 2004

Renuganth Varatharajoo and Mohamad Tarmizi Ahmad

Flywheels can serve not only as attitude control devices, but also as energy storage devices, thereby eliminating the need for conventional batteries. Hence, a combined energy and…

Abstract

Flywheels can serve not only as attitude control devices, but also as energy storage devices, thereby eliminating the need for conventional batteries. Hence, a combined energy and attitude control system (CEACS) consisting of a double counter rotating flywheel assembly is proposed for small satellites in this paper. The energy level in CEACS depends mainly on the flywheels' speeds. Therefore, a specific flywheel energy management strategy has to be implemented to take into account the limitations of the flywheels, which has not been established until today.

Details

Aircraft Engineering and Aerospace Technology, vol. 76 no. 4
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 1 June 2005

Oghenevwogaga Benson Adogbeji and Esharenana E. Adomi

The study reports on the decision to go forward with plans for library automation, and its details, including the number of computers/their capacity, the networking pattern used…

1591

Abstract

Purpose

The study reports on the decision to go forward with plans for library automation, and its details, including the number of computers/their capacity, the networking pattern used in the automation of the Delta State library and the operating systems. A review of the library software currently in use – X‐LIB, and the general features of the software, the required training in general computer application and how to use the X‐LIB, and handle data entry and retrospective conversion is covered. The article also speculates about the future plan of the library and the constraints it may experience due to the automation plan.

Design/methodology/approach

The work was based on the report/experience of the Delta State University library in implementing automation with the use of X‐LIB. The researcher adopted a descriptive method to reveal the state of automation of the university library and the experience to date. This is a descriptive case study about implementation of X‐LIB software.

Findings

Automation requires intensive staff training and forces future planning for subsequent phases and developments. Research limitations/implications The obvious implications are scale and financial resources, staff development and how far in the future a library wants to stage this phase of implementation. Many libraries already have invested in this process and refined it but in cases like this institution, library automation is still young.

Practical Implications

Useful, practical insights based on local experience is what is described.

Value

As a case study other libraries considering this product or going in this direction will find this submission of interest.

Details

Library Hi Tech News, vol. 22 no. 5
Type: Research Article
ISSN: 0741-9058

Keywords

Article
Publication date: 2 April 2021

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. The…

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. 39 no. 2
Type: Research Article
ISSN: 0265-671X

Keywords

Article
Publication date: 26 August 2021

Sujata S.B. and Anuradha M. Sandi

The small area network for data communication within routers is suffering from storage of packet, throughput, latency and power consumption. There are a lot of solutions to…

Abstract

Purpose

The small area network for data communication within routers is suffering from storage of packet, throughput, latency and power consumption. There are a lot of solutions to increase speed of commutation and optimization of power consumption; one among them is Network-on-chip (NoC). In the literature, there are several NoCs which can reconfigurable dynamically and can easily test and validate the results on FPGA. But still, NoCs have limitations which are regarding chip area, reconfigurable time and throughput.

Design/methodology/approach

To address these limitations, this research proposes the dynamically buffered and bufferless reconfigurable NoC (DB2R NoC) using X-Y algorithm for routing, Torus for switching and Flexible Direction Order (FDOR) for direction finding between source and destination nodes. Thus, the 3 × 3 and 4 × 4 DB2R NoCs are made free from deadlock, low power and latency and high throughput. To prove the applicability and performance analysis of DB2R NoC for 3 × 3 and 4 × 4 routers on FPGA, the 22 bits for buffered and 19 bit for bufferless designs have been successfully synthesized using Verilog HDL and implemented on Artix-7 FPGA development bond. The virtual input/output chips cope pro tool has been incorporated in the design to verify and debug the complete design on Artix-7 FPGA.

Findings

In the obtained result, it has been found that 35% improvement in throughput, 23% improvement in latency and 47% optimization in area has been made. The complete design has been tested for 28 packets of injection rate 0.01; the packets have been generated by using NLFSR.

Originality/value

In the obtained result, it has been found that 35% improvement in throughput, 23% improvement in latency and 47% optimization in area has been made. The complete design has been tested for 28 packets of injection rate 0.01; the packets have been generated by using NLFSR.

Details

International Journal of Pervasive Computing and Communications, vol. 18 no. 2
Type: Research Article
ISSN: 1742-7371

Keywords

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