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Article
Publication date: 1 June 1996

D. Mukherjee, S. Muralidharan, G.T. Parthiban, D. Jayaperumal, S.P. Manoharan and K. Balakrishnan

Sensitization of stainless steels has been posing serious problems to the industries. Techniques for rapid detection of sensitized surfaces are being probed throughout the world…

72

Abstract

Sensitization of stainless steels has been posing serious problems to the industries. Techniques for rapid detection of sensitized surfaces are being probed throughout the world. Characterization over a wide behavioural range is essential for the above. Characterizes sensitized surfaces of AISI 304 stainless steel using impedance and tafel‐extrapolation techniques. Welded 304 stainless steel interfaces were subjected to dissolution tests, in different media, for assessing the effect of prolonged post‐stress relieving on the mitigation of surface dissolution. The corrosion rate values were correlated with the period of sensitization and Huey test results. The sensitized stainless steels were also subjected to electrochemical tests in different solutions. From the impedance behaviour of the sensitized surfaces in 3 per cent NaCl electrolyte, it was observed that the rate of fall in the polarization resistance may be used to monitor the extent of sensitization in 304 stainless steel, with better accuracy, than that in utilizing the polarization resistance itself.

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Anti-Corrosion Methods and Materials, vol. 43 no. 6
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 10 October 2016

Santosh Kumar Choudhary

The purpose of this paper is to investigate an optimal control solution with prescribed degree of stability for the position and tracking control problem of the twin rotor…

270

Abstract

Purpose

The purpose of this paper is to investigate an optimal control solution with prescribed degree of stability for the position and tracking control problem of the twin rotor multiple input-multiple output (MIMO) system (TRMS). The twin rotor MIMO system is a benchmark aerodynamical laboratory model having strongly non-linear characteristics and unstable coupling dynamics which make the control of such system for either posture stabilization or trajectory tracking a challenging task.

Design/methodology/approach

This paper first describes the dynamical model of twin rotor MIMO system (TRMS) and then it adopts linear-quadratic regulator (LQR)-based optimal control technique with prescribed degree of stability to achieve the desired trajectory or posture stabilization of TRMS.

Findings

The simulation results show that the investigated controller has both static and dynamic performance; therefore, the stability and the quick control effect can be obtained simultaneously for the twin rotor MIMO system.

Originality/value

The articles on LQR optimal controllers for TRMS can also be found in many literatures, but the prescribed degree of stability concept was not discussed in any of the paper. In this work, new LQR with the prescribed degree of stability concept is applied to provide an optimal control solution for the position and tracking control problem of TRMS.

Details

International Journal of Intelligent Unmanned Systems, vol. 4 no. 4
Type: Research Article
ISSN: 2049-6427

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Article
Publication date: 17 January 2018

Balachandar Pandiyan, Sivarajan Ganesan, Nadanasabapathy Jayakumar and Srikrishna Subramanian

The ever-stringent environmental regulations force power producers to produce electricity at the cheapest price and with minimum pollutant emission levels. The electrical power…

143

Abstract

Purpose

The ever-stringent environmental regulations force power producers to produce electricity at the cheapest price and with minimum pollutant emission levels. The electrical power generation from fossil fuel releases several contaminants into the air, and this becomes excrescent if the generating unit is fed by multiple fuel sources (MFSs). Inclusion of this issue in operational tasks is a welcome perspective. This paper aims to develop a multi-objective model comprising total fuel cost and pollutant emission.

Design/methodology/approach

The cost-effective and environmentally responsive power system operations in the presence of MFSs can be recognised as a multi-objective constrained optimisation problem with conflicting operational objectives. The complexity of the problem requires a suitable optimisation tool. Ant lion algorithm (ALA), the most recent nature-inspired algorithm, was used as the main optimisation tool because of its salient characteristics. The fuzzy decision-making mechanism has been integrated to determine the best compromised solution in the multi-objective framework.

Findings

This paper is the first to propose a more precise and practical operational model for studying a multi-fuel power dispatch scenario considering valve-point effects and CO2 emission. The modern meta-heuristic algorithm ALA is applied for the first time to address the economic operation of thermal power systems with multiple fuel options.

Practical implications

Power companies aim to make profit by abiding by the norms of the regulatory board. To achieve economic benefits, the power system must be analysed using an accurate operational model. The proposed model integrates total fuel cost, valve-point loadings and CO2 emission, which are prevailing power system operational objectives. The economic advantages of the operational model can be observed through economic deviation indices, and the performed analysis validates that the developed model corresponds to the actual power operation.

Originality/value

The realistic operational model is proposed by considering total fuel and pollutant emission, and the ALA is applied for the first time to address the proposed multi-objective problem. To validate the effectiveness of ALA, it is implemented in standard test systems with varying generating units (10-100) and the IEEE 30 bus system, and various kinds of power system operations are performed. Moreover, the comparison and performance analysis confirm that the current proposal is found enhanced in terms of solution quality.

Details

International Journal of Energy Sector Management, vol. 12 no. 1
Type: Research Article
ISSN: 1750-6220

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Article
Publication date: 3 April 2020

Federico Dell'Anna, Marta Bottero, Cristina Becchio, Stefano Paolo Corgnati and Giulio Mondini

The cost-optimal analysis is not able to address the multi-dimensionality of the decision according to the new European objectives and International sustainable development goals…

592

Abstract

Purpose

The cost-optimal analysis is not able to address the multi-dimensionality of the decision according to the new European objectives and International sustainable development goals in the field of the nearly-zero energy building (NZEB) design. The purpose of this paper is to study the role of multi-criteria decision analysis (MCDA) for guiding energy investment decisions.

Design/methodology/approach

The paper explores the Preference ranking organization method for enrichment of evaluations II (PROMETHEE II) application to support the project of transforming a rural building into a NZEB. The evaluation provides an estimate of the effects of alternative energy efficiency measures, involving energy consumption, life cycle costs, carbon emissions, property value and indoor comfort criteria. The study performs a multi-actors analysis in order to understand how different consumers' point of views can influence the final choice of the best investment. Furthermore, a multi-site analysis explores the spatial variation of NZEB building appreciation in the real estate market.

Findings

The PROMETHEE II-based model ranks 16 alternative solutions for the NZEB according to energy, economic and extra-economic criteria. The multi-actors analysis highlights the configuration of the NZEB building that best meets the needs of different end-users, respecting the European directives and national standards. The multi-site analysis concludes that location does not change users' appreciation and not influence the output for the best solution.

Originality/value

The MCDA occurs as a support tool that helps to optimize the preliminary design phase of NZEB through the exploration of the optimal solution considering crucial criteria in the energy and environmental and real estate market rules.

Details

Smart and Sustainable Built Environment, vol. 9 no. 4
Type: Research Article
ISSN: 2046-6099

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Article
Publication date: 14 October 2021

Ankit Kumar Srivastava, A.N. Tiwari and S.N. Singh

This paper aims to accurately estimate harmonics/interharmonics in modern power system. There are several high spectral resolution techniques that have been in use for several…

122

Abstract

Purpose

This paper aims to accurately estimate harmonics/interharmonics in modern power system. There are several high spectral resolution techniques that have been in use for several years like Estimation of Signal Parameters via Rotational Invariance Technique (ESPRIT), Prony methods, etc. but these techniques require prior knowledge of number of modes present in the signal. Model Order (MO) estimation techniques have to make a trade-off between accuracy and their speed i.e., computational burden. Therefore, there is always a requirement of a technique that is fast as well as accurate.

Design/methodology/approach

The proposed standard deviation (SD) method eliminates the requirement of energy validation test and analyses the distribution pattern, i.e. standard deviation of eigenvalues to identify the number of modes present in the signal. Signal is reconstructed using estimated modes and reconstruction error is obtained to show accuracy of the proposed estimation.

Findings

Six test synthetic signals as well as one practical signal have been taken for validating the proposed method. The paper shows that proposed methodology has a better accuracy compared to modified exact model order (MEMO) method in high noise environment and takes very less computation time compared to the exact model order (EMO) method.

Practical implications

The proposed method has been practically implemented for harmonic/interharmonic analysis at a sewage treatment plant at GIFT City, Gujarat, India. Apart from this the proposed method is modeled in python-based tool and is run into low-cost Raspberry Pi like hardware to create an onsite as well as remote monitoring device.

Originality/value

SD-based approach for model order estimation is novel to this area. Further, the proposed method is compared with EMO and MEMO under varying noise conditions to check for accuracy and estimation time.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 40 no. 6
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 23 May 2019

Mohd Imran Khan, Shahbaz Khan and Abid Haleem

Assurance of Halal integrity up to the consumption point requires a supply chain approach. Credence quality attributes of Halal products make adoption and management of Halal…

1262

Abstract

Purpose

Assurance of Halal integrity up to the consumption point requires a supply chain approach. Credence quality attributes of Halal products make adoption and management of Halal practices along the whole supply chain a challenging task. This paper aims to explore and evaluate the barriers in the management of the Halal supply chain.

Design/methodology/approach

This paper reviews the contemporary literature regarding Halal and management of Halal supply chain and subsequently identifies significant barriers towards managing the Halal supply chain. Further, these barriers are examined quantitatively using Best Worst Method.

Findings

This study has established significant barriers to Halal supply chain management. Moreover, prioritisation of barriers gives a hierarchy to mitigate these significant barriers. The analysis suggests that reduced demand for Halal products is the highly weighted barrier. Improper laws to regulate the Halal industry and lack of policy framework are hindering the effective management of the Halal supply chain.

Research limitations/implications

This study explored a limited number of barriers; it may be possible that some barriers might not have captured. Further, the identified barriers are generic and validated in the context of multicultural societies. Expert opinion has been used to obtain the weight of barriers which may be biased.

Originality/value

To the best of author’s knowledge, no study has categorically explored and presented a holistic framework to mitigate barriers of managing Halal practices in the supply chain.

Details

Journal of Islamic Marketing, vol. 13 no. 1
Type: Research Article
ISSN: 1759-0833

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Article
Publication date: 16 November 2015

Augustine Adomah-Afari

The purpose of this paper is to investigate the effect of social dynamics on the performance of mutual health organisations (MHOs) exploring the influence of community wealth and…

404

Abstract

Purpose

The purpose of this paper is to investigate the effect of social dynamics on the performance of mutual health organisations (MHOs) exploring the influence of community wealth and community leadership on policy implementation.

Design/methodology/approach

Four operating district mutual health insurance schemes were selected using geographical locations, among other criteria, as case studies. Data were gathered through interviews and documentary review. The findings were analysed using community field and social capital theories.

Findings

Traditional leaders like the Chiefs serve as the pivot around which social and human capital of the communities revolve in the developmental process of the country.

Research limitations/implications

Lack of exhaustive examination of the financial and institutional viability issues of the MHOs. Future studies could assess the interplay between financial, institutional and social viability models when measuring the financial and overall sustainability of MHOs.

Practical implications

Health policy makers need to involve traditional leaders in the formulation and implementation of national policies since their acceptance or rejection of central government policy could have negative consequences.

Social implications

Ghana is a dynamic country and there is the need to utilise existing social networks: inter-family and inter-tribal relationships to ensure the viability of MHOs.

Originality/value

There is and can be a successful interplay between public sector funding and community sector revenue mobilisation for financing the health sector in Ghana. This justifies the complementarity between government funding and community’s resource mobilisation efforts in the health sector.

Details

Journal of Health Organization and Management, vol. 29 no. 7
Type: Research Article
ISSN: 1477-7266

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Article
Publication date: 28 October 2014

Vasundhara Mahajan, Pramod Agarwal and Hari Om Gupta

The active power filter with two-level inverter needs a high-rating coupling transformer for high-power applications. This complicates the control and system becomes bulky and…

285

Abstract

Purpose

The active power filter with two-level inverter needs a high-rating coupling transformer for high-power applications. This complicates the control and system becomes bulky and expensive. The purpose of this paper is to motivate the use of multilevel inverter as harmonic filter, which eliminates the coupling transformer and allows direct control of the power circuit. The advancement in artificial intelligence (AI) for computation is explored for controller design.

Design/methodology/approach

The proposed scheme has a five-level cascaded H-bridge multilevel inverter (CHBMLI) as a harmonic filter. The control scheme includes one neural network controller and two fuzzy logic-based controllers for harmonic extraction, dc capacitor voltage balancing, and compensating current adjustment, respectively. The topology is modeled in MATLAB/SIMULINK and implemented using dSPACE DS1103 interface for experimentation.

Findings

The exhaustive simulation and experimental results demonstrate the robustness and effectiveness of the proposed topology and controllers for harmonic minimization for RL/RC load and change in load. The comparison between traditional PI controller and proposed AI-based controller is presented. It indicates that the AI-based controller is fast, dynamic, and adaptive to accommodate the changes in load. The total harmonic distortion obtained by applying AI-based controllers are well within the IEEE519 std. limits.

Originality/value

The simulation of high-power, medium-voltage system is presented and a downscaled prototype is designed and developed for implementation. The laboratory module of CHBMLI-based harmonic filter and AI-based controllers modeled in SIMULINK is executed using dSPACE DS1103 interface through real time workshop.

Details

COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, vol. 33 no. 6
Type: Research Article
ISSN: 0332-1649

Keywords

Available. Open Access. Open Access
Article
Publication date: 20 May 2024

Kesavan Manoharan, Pujitha Dissanayake, Chintha Pathirana, Dharsana Deegahawature and Renuka Silva

Productivity increase is correlated with profitability, sustainability and competitiveness of the construction firms. Recent studies reveal that the primary causes of productivity…

707

Abstract

Purpose

Productivity increase is correlated with profitability, sustainability and competitiveness of the construction firms. Recent studies reveal that the primary causes of productivity decline are poor usage of scientific and technological advances, ineffective supervision strategies and poor apprenticeship facilities/opportunities. Accordingly, the purpose of this study was to evaluate how well construction supervisors can utilise fundamental science and technological concepts/ideas to increase the efficiency and productivity of construction activities.

Design/methodology/approach

A new strategic layout was designed with the use of potential training guide tools. Based on the designed layout, a new supervisory training programme was developed, and 62 construction supervisors were selected, trained and evaluated in line with six parts of competencies and the relevant learning domains. An assessment guide with different levels of descriptions and criteria was developed through literature analysis and expert interviews. The research tools were verified using comprehensive approaches.

Findings

The overall mean values of supervisors’ performance scores indicate proficient-level grades in the competency characteristics related to taking measurements, generating drawings/designs using manual techniques and computer-aided tools, involving Bill of Quantities (BOQ) preparations and preparing training plans/materials for improving the competencies of labourers on estimation, measurements and understanding drawings. Their proficiency was notably lower in the use of information and communication technology application tools in construction tasks compared to others. The findings point to a modern generalised guideline that establishes the ranges of supervisory attributes associated with science and technology-related applications.

Research limitations/implications

The study outcomes produce conceptualised projections to restructure and revalue the job functions of various working categories by adding new definitions within the specified scope. This may result in constructive benefits to upgrading the current functions associated with urbanisation, sustainability and society. The implementation of the study’s findings/conclusions will have a significant impact on present and future practices in other developing nations and developing industries, even if they are directly applicable to the Sri Lankan construction industry.

Originality/value

Up to certain limits/stages, the study fills not only the knowledge gap in the field of creating protocols and application techniques connected to lifelong learning and skill enhancement/upgrading but also the existing gaps in work attributes and roles of construction supervisors associated with the utilisation of fundamental science and technological concepts/ideas towards reinforcing sustainable and productive site operations.

Details

Urbanization, Sustainability and Society, vol. 1 no. 1
Type: Research Article
ISSN: 2976-8993

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Article
Publication date: 17 February 2022

Kesavan Manoharan, Pujitha B.G. Dissanayake, Chintha Pathirana, Dharsana Deegahawature and K.D. Renuka Ruchira Silva

The performance-based utilisation of labour resources is a decisive function for developing characteristics of the next normal in the construction industry. Based on the industry's

339

Abstract

Purpose

The performance-based utilisation of labour resources is a decisive function for developing characteristics of the next normal in the construction industry. Based on the industry's needs, this study aims to develop a framework for the systematic process of labour performance evaluations and labour grading towards achieving higher productivity in construction operations.

Design/methodology/approach

Both qualitative and quantitative methods were applied through a comprehensive literature review, surveys and experts' discussions to develop a set of labour training elements of outcomes. Problem-focused and action-oriented communication approaches were used throughout the study to produce detailed steps for the systematic evaluations of labour performance.

Findings

The study has presented a framework consisting of a set of labour training elements of outcomes with the relative weights, as well as the detailed procedures to assess labour competencies towards the calculations of labour performance score values and labour grading.

Research limitations/implications

Although the scope of the study is limited to the Sri Lankan context, the findings may be tested in other countries for upgrading their performance improvement practices of labour operations.

Practical implications

The study outcomes will strengthen the construction management practices for the successful implementation of labour training and performance evaluations at construction sites, and also contribute to upgrading the vocational training programmes in the country towards the next sustainable normal.

Originality/value

The developed framework can be a functional tool for the construction industry that provides a mechanism to show the detailed cross-section of each labourer's performance and values, and also displays their roles and responsibilities to accelerate the next normal in the construction industry.

Details

Built Environment Project and Asset Management, vol. 13 no. 1
Type: Research Article
ISSN: 2044-124X

Keywords

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