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Article
Publication date: 12 August 2021

Wasiq Ullah, Faisal Khan, Muhammad Umair and Bakhtiar Khan

This paper aims to reviewed analytical methodologies, i.e. lumped parameter magnetic equivalent circuit (LPMEC), magnetic co-energy (MCE), Laplace equations (LE), Maxwell…

Abstract

Purpose

This paper aims to reviewed analytical methodologies, i.e. lumped parameter magnetic equivalent circuit (LPMEC), magnetic co-energy (MCE), Laplace equations (LE), Maxwell stress tensor (MST) method and sub-domain modelling for design of segmented PM(SPM) consequent pole flux switching machine (SPMCPFSM). Electric machines, especially flux switching machines (FSMs), are accurately modeled using numerical-based finite element analysis (FEA) tools; however, despite of expensive hardware setup, repeated iterative process, complex stator design and permanent magnet (PM) non-linear behavior increases computational time and complexity.

Design/methodology/approach

This paper reviews various alternate analytical methodologies for electromagnetic performance calculation. In above-mentioned analytical methodologies, no-load phase flux linkage is performed using LPMEC, magnetic co-energy for cogging torque, LE for magnetic flux density (MFD) components, i.e. radial and tangential and MST for instantaneous torque. Sub-domain model solves electromagnetic performance, i.e. MFD and torque behaviour.

Findings

The reviewed analytical methodologies are validated with globally accepted FEA using JMAG Commercial FEA Package v. 18.1 which shows good agreement with accuracy. In comparison of analytical methodologies, analysis reveals that sub-domain model not only get rid of multiples techniques for validation purpose but also provide better results by accounting influence of all machine parts which helps to reduce computational complexity, computational time and drive storage with overall accuracy of ∼99%. Furthermore, authors are confident to recommend sub-domain model for initial design stage of SPMCPFSM when higher accuracy and low computational cost are primal requirements.

Practical implications

The model is developed for high-speed brushless AC applications.

Originality/value

The SPMCPFSM enhances electromagnetic performance owing to segmented PMs configuration which makes it different than conventional designs. Moreover, developed analytical methodologies for SPMCPFSM reduce computational time compared with that of FEA.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 40 no. 3
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 5 January 2022

Basharat Ullah, Faisal Khan, Bakhtiar Khan and Muhammad Yousuf

The purpose of this paper is to analyze electromagnetic performance and develop an analytical approach to find the suitable coil combination and no-load flux linkage of…

Abstract

Purpose

The purpose of this paper is to analyze electromagnetic performance and develop an analytical approach to find the suitable coil combination and no-load flux linkage of the proposed hybrid excited consequent pole flux switching machine (HECPFSM) while minimizing the drive storage and computational time which is the main problem in finite element analysis (FEA) tools.

Design/methodology/approach

First, a new HECPFSM based on conventional consequent pole flux switching permanent machine (FSPM) is proposed, and lumped parameter magnetic network model (LPMNM) is developed for the initial analysis like coil combination and no-load flux linkage. In LPMNM, all the parts of one-third machine are modeled which helps in reduction of drive storage, computational complexity and computational time without affecting the accuracy. Second, self and mutual inductance are calculated in the stator, and dq-axis inductance is calculated using park transformation in the rotor of the proposed machine. Furthermore, on-load performance analysis, like average torque, torque density and efficiency, is done by FEA.

Findings

The developed LPMNM is validated by FEA via JMAG v. 19.1. The results obtained show good agreement with an accuracy of 96.89%.

Practical implications

The proposed HECPFSM is developed for high-speed brushless AC applications like electric vehicle (EV)/hybrid electric vehicle (HEV).

Originality/value

The proposed HECPFSM offers better flux regulation capability with enhanced electromagnetic performance as compared to conventional consequent pole FSPM. Moreover, the developed LPMNM reduces drive storage and computational time by modeling one-third of the machine.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 41 no. 5
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 18 September 2019

Ghobad Moradi, Amjad Mohamadi-Bolbanabad, Sonia Darvishi, Fatemeh Azimian Zavareh, Bakhtiar Piroozi, Bushra Zareie, Mohammad-Mehdi Gouya and Mehrzad Tashakorian

The purpose of this paper is to determine patterns of sexual behaviors and related factors among prisoners in Iran, 2015.

Abstract

Purpose

The purpose of this paper is to determine patterns of sexual behaviors and related factors among prisoners in Iran, 2015.

Design/methodology/approach

This cross-sectional study was a part of a bio-behavioral surveillance survey conducted on 6,200 prisoners in 26 prisons in Iran. The subjects were selected through multi-stage sampling. Questionnaires and interviews were used to collect data on participant’s demographics and history of sexual behaviors. Using STATA-12 software, the collected data were analyzed through descriptive statistics, and crude and adjusted logistic regression.

Findings

A total of 5,508 prisoners with a response rate of 88.8 percent participated in this study. Of all prisoners, 55 percent (n=3,027) had a history of “unsafe sex in the lifetime” of whom 53.4 percent (n=1,549) never used condoms during unsafe sex in the lifetime. Based on the results of multivariate analysis, risk factors for “unsafe sex in lifetime” were the following: higher level of education (AOR=1.79, CI: 1.41–2.28), being single (AOR=1.32, CI: 1.18–1.47), unemployed before imprisonment (AOR=1.45, CI: 1.06–1.97), having history of previous imprisonment (AOR=1.31, CI: 1.17–1.47) and history of drug use in the lifetime (AOR=1.53, CI: 1.35–1.75).

Originality/value

Prisoners are high-risk groups that are prone to practice unsafe sex. Prisoners who are single, unemployed before imprisonment, a drug user, with a higher level of education and with a history of imprisonment are likely to be sexually active in their lifetime. Thus, they are a priority for receiving suitable interventions.

Details

International Journal of Prisoner Health, vol. 16 no. 1
Type: Research Article
ISSN: 1744-9200

Keywords

Executive summary
Publication date: 5 October 2018

PAKISTAN: U-turn betrays China’s control of corridor

Details

DOI: 10.1108/OXAN-ES238977

ISSN: 2633-304X

Keywords

Geographic
Topical
Article
Publication date: 20 October 2021

Pantea Hakimian and Azadeh Lak

The purpose of this study is to develop a conceptual framework for defining the notion of “physical integration” regarding the Iranian bazaar as the main component in the…

Abstract

Purpose

The purpose of this study is to develop a conceptual framework for defining the notion of “physical integration” regarding the Iranian bazaar as the main component in the structure of traditional Iranian cities. Applying this conceptual framework to the historical bazaars in the cities of Kerman and Shiraz, this study seeks to pave the way for restoring the physical integrity of such historical districts.

Design/methodology/approach

The research was conducted in two phases. First, there was a review of the theoretical background of physical integration followed by the analysis of the corresponding qualitative contents and the validation of the proposed conceptual framework as confirmed by 15 local experts. The second phase tested the validated framework in two case studies based on maps, historical documents and field observations.

Findings

The findings show that the physical integration of historical bazaars can be undertaken in morphological, visual-aesthetic and functional aspects. The proposed conceptual framework is capable of dealing with the different aspects of physical integration in historical districts on a meso-scale.

Research limitations/implications

The theoretical implications of this study concerning the physical integration of traditional bazaars address urban design, urban planning and multi-disciplinary historical geography. The study also has practical implications for the integration of bazaars in historical urban regeneration projects via design guidelines.

Originality/value

This study emphasizes the importance of physical integration as a multi-dimensional concept, facilitating it to deal with the physical quality and the characteristics of historical districts, particularly bazaars. It also highlights the role of the Iranian bazaar as a unifying structure in the historical districts.

Details

Journal of Cultural Heritage Management and Sustainable Development, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2044-1266

Keywords

Article
Publication date: 9 August 2021

Zuraidah Mohd-Sanusi, Yusarina Mat-Isa, Ahmad Haziq Ahmad-Bakhtiar, Yusri Huzaimi Mat-Jusoh and Tarjo Tarjo

This study aims to examine the direct and indirect effects of professional commitment, customer risk and independence pressure on money laundering risk judgment among bank…

Abstract

Purpose

This study aims to examine the direct and indirect effects of professional commitment, customer risk and independence pressure on money laundering risk judgment among bank analysts.

Design/methodology/approach

This study uses a within-subjects experimental research design and collects primary data via a questionnaire distributed to bank analysts in banking institutions in Malaysia.

Findings

Results show that professional commitment, customer risk and independence pressure significantly influence money laundering risk judgment (i.e. customer due diligence and money laundering reporting). The results also show significant interaction effects between customer risk and independence pressure in influencing money laundering risk judgment.

Practical implications

Professional commitment and situational factors are crucial in putting pressure on bank analysts responsible for performing a thorough check and due diligence to minimize money laundering risk to the bank.

Social implications

As money laundering is lifeblood of crimes, understanding the factors influencing money laundering risk judgment would assist the affected institutions to manage the risk better and contribute towards the fight against crimes.

Originality/value

This study focuses on money laundering risk judgment. It contributes to understanding the competency of the gatekeepers, such as bank analysts, in practicing professional commitment and dealing with situational factors.

Details

Journal of Money Laundering Control, vol. 25 no. 3
Type: Research Article
ISSN: 1368-5201

Keywords

Article
Publication date: 12 March 2018

Sepideh Yazdekhasti, Kalyan Ram Piratla, John C. Matthews, Abdul Khan and Sez Atamturktur

There has been a sustained interest over the past couple of decades in developing sophisticated leak detection techniques (LDTs) that are economical and reliable. Majority…

Abstract

Purpose

There has been a sustained interest over the past couple of decades in developing sophisticated leak detection techniques (LDTs) that are economical and reliable. Majority of current commercial LDTs are acoustics based and they are not equally suitable to all pipe materials and sizes. There is also limited knowledge on the comparative merits of such acoustics-based leak detection techniques (ALDTs). The purpose of this paper is to review six commercial ALDTs based on four decisive criteria and subsequently develop guidance for the optimal selection of an ALDT.

Design/methodology/approach

Numerous publications and field demonstration reports are reviewed for evaluating the performance of various ALDTs in this study to inform their optimal selection using an integrated multi-criteria decision analysis (MCDA) framework. The findings are validated using interviews of water utility experts.

Findings

The study approach and the findings will have a broad impact on the water utility industry by identifying a suite of suitable ALDTs for a range of typical application scenarios. The evaluated ALDTs include listening devices, noise loggers, leak-noise correlators, free-swimming acoustic, tethered acoustic, and acoustic emissions. The evaluation criteria include cost, reliability, access requirements, and the ability to quantify leakage severity. The guidance presented in this paper will support efficient decision making in water utility management to minimize pipeline leakage.

Originality/value

This study attempts to address the problem of severe dearth of performance data for pipeline inspection techniques. Performance data reported in the published literature on various ALDTs are appropriately aggregated and compared using a MCDA, while the uncertainty in performance data is addressed using the Monte Carlo simulation approach.

Details

Management of Environmental Quality: An International Journal, vol. 29 no. 2
Type: Research Article
ISSN: 1477-7835

Keywords

Article
Publication date: 4 August 2021

Asieh Bakhtiar, Seyed Sepehr Ghazinoory, Alireza Aslani and Vahid Mafi

The purpose of this paper is to present and evaluate the performance of innovation systems by considering two indicators of efficiency and effectiveness. The scope of the…

Abstract

Purpose

The purpose of this paper is to present and evaluate the performance of innovation systems by considering two indicators of efficiency and effectiveness. The scope of the evaluation is globally and due to the situation of each country, the suggested strategies are proposed to maintain the status quo or move toward the desired situation for countries.

Design/methodology/approach

The approach is to compare and benchmark the countries in terms of the efficiency and effectiveness of their innovation system. The Global Innovation Index report’s input-to-output ratio and the global competitiveness report are used for the assessment.

Findings

The findings indicate that countries such as China, Switzerland and the USA have an efficient and effective innovation system. However, the innovation systems in countries such as Brazil and Zimbabwe are not only inefficient but also ineffective. The findings also indicate that the innovation systems of countries such as Iran, Armenia and Egypt are efficient but ineffective. Finally, the authors can name Australia, Qatar and Russia as countries with effective but inefficient innovation systems.

Originality/value

Assessment of national innovation system using efficiency and effectiveness performances is done for the first time at the global stage.

Details

Journal of Science and Technology Policy Management, vol. 13 no. 3
Type: Research Article
ISSN: 2053-4620

Keywords

Article
Publication date: 1 February 2022

Syed Tehseen Jawaid, Lubna Khan and Imtiaz Arif

Despite the reasonable surge of remittances and imports in Pakistan, very less attention has been given to this area. To bridge the gap, this study aims to explore the…

Abstract

Purpose

Despite the reasonable surge of remittances and imports in Pakistan, very less attention has been given to this area. To bridge the gap, this study aims to explore the relationship of worker’s remittances and imports of Pakistan at both aggregate and disaggregate levels. Also, this research focuses on investigating whether remitted income substitute or complement imports of the country.

Design/methodology/approach

To achieve these goals, the authors use annual time-series data from 1974–2016.

Findings

Empirical findings obtained from the autoregressive distributed lag model method suggest that remittances substitute imports in Pakistan. It is also found that remittances not only substitute aggregate imports but also act as a substitute at different disaggregated levels. Further, it is documented that higher economic growth increases imports, whereas the real exchange rate for imports is inversely related to imports at both levels.

Originality/value

These empirical findings also draw some substantive policy implications for the state owners and policy advisers.

Details

Journal of Chinese Economic and Foreign Trade Studies, vol. 15 no. 1
Type: Research Article
ISSN: 1754-4408

Keywords

Content available
Article
Publication date: 1 May 2006

104

Abstract

Details

Disaster Prevention and Management: An International Journal, vol. 15 no. 3
Type: Research Article
ISSN: 0965-3562

1 – 10 of 31