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Article
Publication date: 6 November 2017

Ishu Sharma and K.R. Ramkumar

The purpose of this paper is to review the existing routing algorithms for wireless ad hoc networks to evaluate the methods according to the current requirements. Wireless ad hoc…

169

Abstract

Purpose

The purpose of this paper is to review the existing routing algorithms for wireless ad hoc networks to evaluate the methods according to the current requirements. Wireless ad hoc network can provide communication in emergency situations. Active nodes in ad hoc network work as sender, receiver and router at the same time. Nodes are equipped with limited bandwidth and energy. Optimal routing method can help in “smart use” of available resources. Evolvement of routing method based on need is a continuous process. Numerous applications of ad hoc network motivates researcher for further development to fulfill the need of society.

Design/methodology/approach

In this paper, routing algorithms for ad hoc network based on ant colony optimization, multipath routing and with multiple input multiple output (MIMO) antenna support have been discussed.

Findings

Comparative analysis has been drawn among existing algorithms of different categories. Transmitting message packets parallel through multiple paths in the network can save overall resource usage in the network.

Originality/value

The authors have discussed the future area of development for optimal routing in ad hoc networks. Considering signal noise ratio and congestion status while selecting path can provide better energy use in the network. Rather than leaving less prioritized route paths, multiple paths can be used for sending data packets parallel.

Details

International Journal of Pervasive Computing and Communications, vol. 13 no. 4
Type: Research Article
ISSN: 1742-7371

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Article
Publication date: 4 September 2017

Shailja Agnihotri and K.R. Ramkumar

The purpose of this paper is to provide insight into various swarm intelligence-based routing protocols for Internet of Things (IoT), which are currently available for the Mobile…

534

Abstract

Purpose

The purpose of this paper is to provide insight into various swarm intelligence-based routing protocols for Internet of Things (IoT), which are currently available for the Mobile Ad-hoc networks (MANETs) and wireless sensor networks (WSNs). There are several issues which are limiting the growth of IoT. These include privacy, security, reliability, link failures, routing, heterogeneity, etc. The routing issues of MANETs and WSNs impose almost the same requirements for IoT routing mechanism. The recent work of worldwide researchers is focused on this area.

Design/methodology/approach

The paper provides the literature review for various standard routing protocols. The different comparative analysis of the routing protocols is done. The paper surveys various routing protocols available for the seamless connectivity of things in IoT. Various features, advantages and challenges of the said protocols are discussed. The protocols are based on the principles of swarm intelligence. Swarm intelligence is applied to achieve optimality and efficiency in solving the complex, multi-hop and dynamic requirements of the wireless networks. The application of the ant colony optimization technique tries to provide answers to many routing issues.

Findings

Using the swarm intelligence and ant colony optimization principles, it has been seen that the protocols’ efficiency definitely increases and also provides more scope for the development of more robust, reliable and efficient routing protocols for the IoT.

Research limitations/implications

The existing protocols do not solve all reliability issues and efficient routing is still not achieved completely. As of now no techniques or protocols are efficient enough to cover all the issues and provide the solution. There is a need to develop new protocols for the communication which will cater to all these needs. Efficient and scalable routing protocols adaptable to different scenarios and network size variation capable to find optimal routes are required.

Practical implications

The various routing protocols are discussed and there is also an introduction to new parameters which can strengthen the protocols. This can lead to encouragement of readers, as well as researchers, to analyze and develop new routing algorithms.

Social implications

The paper provides better understanding of the various routing protocols and provides better comparative analysis for the use of swarm-based research methodology in the development of routing algorithms exclusively for the IoT.

Originality/value

This is a review paper which discusses the various routing protocols available for MANETs and WSNs and provides the groundwork for the development of new intelligent routing protocols for IoT.

Details

International Journal of Pervasive Computing and Communications, vol. 13 no. 3
Type: Research Article
ISSN: 1742-7371

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Article
Publication date: 7 August 2019

Nadjib Benaouda and Ammar Lahlouhi

The purpose of this paper is to present a novel delay-bounded and power-efficient routing for in-network data aggregation, called DPIDA, which aims to ensure a compromise between…

61

Abstract

Purpose

The purpose of this paper is to present a novel delay-bounded and power-efficient routing for in-network data aggregation, called DPIDA, which aims to ensure a compromise between the energy consumed during the collection of data sensed by a set of source sensor nodes and their timely delivery to the sink node.

Design/methodology/approach

Based on the ant-colony-optimization metaheuristic, the proposal establishes a routing structure that maximizes the number of overlapping routes and minimizes the total transmission power while ensuring delay-bounded paths and a symmetric transmission power assignment to reliably deliver the sensed data.

Findings

The proposal was extensively compared to two other known protocols regarding different keys factors. Simulation results, including topology snapshots, show the ability of DPIDA to ensure the energy–latency tradeoff. They also show the superiority of DPIDA compared to the two considered protocols.

Originality/value

This paper presents a novel ant-based protocol that uses in-network data aggregation and transmission power-adjustment techniques to conserve the energy of nodes while ensuring delay-bounded paths and a reliable deliverance of data which is ensured by providing a symmetric transmission power assignment.

Details

International Journal of Pervasive Computing and Communications, vol. 15 no. 2
Type: Research Article
ISSN: 1742-7371

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Article
Publication date: 5 April 2024

K.G. Rumesh Samarawickrama, U.G. Samudrika Wijayapala and C.A. Nandana Fernando

The purpose of this study is to extract and characterize a novel natural dye from the leaves of Lannea coromandelica and the extraction with finding ways of dyeing cotton fabric…

53

Abstract

Purpose

The purpose of this study is to extract and characterize a novel natural dye from the leaves of Lannea coromandelica and the extraction with finding ways of dyeing cotton fabric using three mordants.

Design/methodology/approach

The colouring agents were extracted from the leaves of Lannea coromandelica using an aqueous extraction method. The extract was characterized using analysis methods of pH, gas chromatography-mass spectrometry (GC-MS), Fourier transform infrared (FTIR), ultraviolet-visible (UV-vis) and cyclic voltammetry measurement. The extract was applied to cotton fabric samples using a non-mordant and three mordants under the two mordanting methods. The dyeing performance of the extracted colouring agent was evaluated using colour fastness properties, colour strength (K/S) and colour space (CIE Lab).

Findings

The aqueous dye extract showed reddish-brown colour, and its pH was 5.94. The GC-MS analysis revealed that the dye extract from the leaves of Lannea coromandelica contained active chemical compounds. The UV-vis and FTIR analyses found that groups influenced the reddish-brown colour of the dye extraction. The cyclic voltammetry measurements discovered the electrochemical properties of the dye extraction. The mordanted fabric samples showed better colour fastness properties than the non-mordanted fabric sample. The K/S and CIE Lab results indicate that the cotton fabric samples dyed with mordants showed more significant dye affinities than non-mordanted fabric samples.

Originality/value

Researchers have never discovered that the Lannea coromandelica leaf extract is a natural dye for cotton fabric dyeing. The findings of this study showed that natural dyes extracted from Lannea coromandelica leaf could be an efficient colouring agent for use in cotton fabric.

Details

Pigment & Resin Technology, vol. 53 no. 6
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 20 June 2016

M. Ramkumar

The increasing complexity and dynamism of new technology implemented or to implement have imposed substantial uncertainties and subjectivities in the risk assessment process. This…

616

Abstract

Purpose

The increasing complexity and dynamism of new technology implemented or to implement have imposed substantial uncertainties and subjectivities in the risk assessment process. This paper aims to present a risk assessment methodology for e-procurement implementation based on modified analytic network process (ANP) coupled with fuzzy inference systems.

Design/methodology/approach

ANP is modified in such a way that the experts can provide necessary data precise numerical value, a range of numerical values, a linguistic term or a fuzzy number. The proposed methodology incorporates knowledge and judgements obtained from experts to carry out identification of risk factors and to assess the risk magnitude of the identified risk factors based on factor index, risk likelihood and risk severity.

Findings

Risk magnitude of third party systems are found to be minor with a belief of 100 per cent, and for in-house systems, the risk is found to be between minor with a belief of 30 per cent and major of 70 per cent. The results indicate that by using the proposed methodology, the technological risk assessment of new technology can be done effectively and efficiently.

Research limitations/implications

Using the results of this study, the practitioners can better know the pros and cons of implementing both in-house and third party e-procurement systems.

Originality/value

The modified ANP is used mainly to structure and prioritize the diverse risk factors. Finally, an illustrative example on technological risk assessment of both in-house and third party e-procurement systems is used to demonstrate the applicability of the proposed methodology in real life situations.

Details

Strategic Outsourcing: An International Journal, vol. 9 no. 2
Type: Research Article
ISSN: 1753-8297

Keywords

Available. Open Access. Open Access
Article
Publication date: 31 October 2018

Mahalingam Ramkumar

The purpose of this paper is to examine the blockchain as a trusted computing platform. Understanding the strengths and limitations of this platform is essential to execute…

3423

Abstract

Purpose

The purpose of this paper is to examine the blockchain as a trusted computing platform. Understanding the strengths and limitations of this platform is essential to execute large-scale real-world applications in blockchains.

Design/methodology/approach

This paper proposes several modifications to conventional blockchain networks to improve the scale and scope of applications.

Findings

Simple modifications to cryptographic protocols for constructing blockchain ledgers, and digital signatures for authentication of transactions, are sufficient to realize a scalable blockchain platform.

Originality/value

The original contributions of this paper are concrete steps to overcome limitations of current blockchain networks.

Details

Journal of Capital Markets Studies, vol. 2 no. 2
Type: Research Article
ISSN: 2514-4774

Keywords

Available. Open Access. Open Access
Article
Publication date: 16 July 2020

Tomasz Matusiak, Arkadiusz Dabrowski and Leszek Golonka

The purpose of this paper is to present the properties of thick-film resistors made of novel pastes prepared from glass and graphite.

1515

Abstract

Purpose

The purpose of this paper is to present the properties of thick-film resistors made of novel pastes prepared from glass and graphite.

Design/methodology/approach

Graphite-based resistors were made of thick-film pastes with different graphite-to-glass mass fraction were prepared and examined. Sheet resistance, temperature coefficient of resistance, impact of humidity and short-term overload were investigated. The properties of the layers fired in atmospheres of air at 550°C and nitrogen at 875°C were compared.

Findings

Graphite-based resistors with various graphite-to-glass ratios made possible to obtain a wide range of sheet resistance from single O/square to few kO/square. These values were dependent on firing atmosphere, paste composition and the number of screen-printed layers. The samples made of paste with 1:1 graphite-to-glass ratio exhibited the temperature coefficient of resistance of about −1,000 ppm/°C, almost independently on the firing atmosphere and presence of a top coating. The resistors fired in the air after coating with overglaze, exhibited significantly lower sheet resistance, reduced impact of humidity and improved power capabilities.

Originality/value

In this paper, graphite-based resistors for applications in typical high-temperature cermet thick-film circuits were presented, whereas typical graphite-based resistors were fabricated in polymer thick-film technology. Owing to very low cost of the graphite, the material is suitable for low-power passive circuits, where components are not subjected into high temperature, above the typical temperature of operation of standard electronic components.

Details

Circuit World, vol. 47 no. 2
Type: Research Article
ISSN: 0305-6120

Keywords

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Article
Publication date: 12 December 2022

Mohit Goswami, M. Ramkumar and Yash Daultani

This research aims to aid product development managers to estimate the expected cost associated with the development of cost-intensive physical prototypes considering transitions…

150

Abstract

Purpose

This research aims to aid product development managers to estimate the expected cost associated with the development of cost-intensive physical prototypes considering transitions associated with pertinent states of quality of the prototype and corresponding decision policies under the Markovian setting.

Design/methodology/approach

The authors evolve two types of optimization-based mathematical models under both deterministic and randomized policies. Under the deterministic policy, the product development managers take certain decisions such as “Do nothing,” “Overhaul,” or “Replace” corresponding to different quality states of prototype such as “Good as new,” “Functional with minor deterioration,” “Functional with major deterioration” and “Non-functional.” Under the randomized policy, the product development managers ascertain the probability distribution associated with these decisions corresponding to various states of quality. In both types of mathematical models, i.e. related to deterministic and randomized settings, minimization of the expected cost of the prototype remains the objective function.

Findings

Employing an illustrative case of the operator cabin from the construction equipment domain, the authors ascertain that randomized policy provides us with better decision interventions such that the expected cost of the prototype remains lower than that associated with the deterministic policy. The authors also ascertain the steady-state probabilities associated with a prototype remaining in a particular quality state. These findings have implications for product development budget, time to market, product quality, etc.

Originality/value

The authors’ work contributes toward the development of optimization-driven mathematical models that can encapsulate the nuances related to the uncertainty of transition of quality states of a prototype, decision policies at each quality state of the prototype while considering such facets for all constituent subsystems of the prototype. As opposed to a typical prescriptive study, their study captures the inherent uncertainties associated with states of quality in the context of prototype testing, etc.

Details

International Journal of Quality & Reliability Management, vol. 40 no. 7
Type: Research Article
ISSN: 0265-671X

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Article
Publication date: 5 May 2015

Busi Rambabu and Y. Srinivasa Rao

The purpose of this paper is to study high-voltage interactions in polymer thick-film resistors, namely, polyvinyl chloride (PVC)-graphite thick-film resistors, and their…

156

Abstract

Purpose

The purpose of this paper is to study high-voltage interactions in polymer thick-film resistors, namely, polyvinyl chloride (PVC)-graphite thick-film resistors, and their applications in universal trimming of these resistors.

Design/methodology/approach

The authors applied high voltages in the form of pulses and impulses of various pulse durations and with different amplitudes to polymer thick-film resistors and observed the variation of resistance of these resistors with high voltages.

Findings

The paper finds that high voltages can be used for trimming of polymer thick-film resistors in both directions, i.e. upwards and downwards.

Research limitations/implications

The research implication of this paper is that polymer thick-film resistors can be trimmed downwards or upwards practically using this method.

Practical implications

The practical implications of this paper is that one can trim the polymer thick-film resistors, namely, PVC–graphite thick-film resistors, in both directions, i.e. upwards and downwards, by using this method.

Originality/value

The value of the paper is in showing that high voltages can be used to trim downwards and also upwards in the case of polymer thick-film resistors. This type of trimming is called universal trimming, developed first time for polymer thick-film resistors.

Details

Microelectronics International, vol. 32 no. 2
Type: Research Article
ISSN: 1356-5362

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Article
Publication date: 1 October 2018

Tunde Isaac Ogedengbe, Taiwo Ebenezer Abioye and Augusta Ijeoma Ekpemogu

The purpose of this study is to conduct gas tungsten arc dissimilar welding of AISI 304 stainless steel and low carbon steel within a process window so as to investigate the…

262

Abstract

Purpose

The purpose of this study is to conduct gas tungsten arc dissimilar welding of AISI 304 stainless steel and low carbon steel within a process window so as to investigate the effects of current, speed and gas flow rate (GFR) on the microstructure and mechanical properties of the weldments.

Design/methodology/approach

The welding experiment was carried out at different combinations of parameters using WN-250S Kaierda electric welding machine. A combination of scanning electron microscopy and energy dispersive X-ray spectroscopy was used to examine the microstructure of the weldments. Micro-hardness and tensile tests were performed using Vickers hardness tester and Instron universal testing machine, respectively. ANOVA was used to analyze the significance of the parameters on the mechanical properties.

Findings

The microstructure of the weld region is characterized with dendritic structure with the existence of ferrite and austenite phases. The utilized parameters show significant effects on the ultimate tensile strength (UTS) of the weldments. The current and GFR were found to be the most and least significant factors, respectively. Both the grain size and weld penetration contributed to the UTS of the weldments. The UTS (427-886 MPa) increased with decreasing current and welding speed. In all samples, the weld region exhibited higher hardness (297-396 HV) than the HAZ in the base metals (maximum of 223 Â ± 6 HV). All the three factors show significant effect with the welding speed contributing mostly to the hardness of the weld region.

Originality/value

The parametric combination that gives the optimum mechanical performance of the dissimilar gas tungsten arc weldments of AISI 304 stainless steel and low carbon steel was established.

Details

World Journal of Engineering, vol. 15 no. 5
Type: Research Article
ISSN: 1708-5284

Keywords

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