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1 – 10 of 32Wasiq 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 stress…
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.
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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 the…
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.
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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.
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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.
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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.
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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 of…
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.
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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.
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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.
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