Sajid Hussain and David Lowther
The losses incurred in ferromagnetic materials under PWM excitations must be predicted accurately to optimize the design of modern electrical machines. The purpose of this paper…
Abstract
Purpose
The losses incurred in ferromagnetic materials under PWM excitations must be predicted accurately to optimize the design of modern electrical machines. The purpose of this paper is to employ mathematical hysteresis models (i.e. classical Preisach model) to predict iron losses in electrical steels under PWM excitation without compromising the computational complexity of the model.
Design/methodology/approach
In this paper, a novel approach based on the dynamic inverse Preisach model is proposed to model the iron losses. The PWM magnetic flux density waveform is decomposed into its harmonic component using Fourier series and a weighted Everett function is computed based on these harmonic components. The Preisach model is applied for the given flux waveform and results are validated against the measurements.
Findings
The paper predicts the total iron loss by computing a weighted Everett function based on the harmonics present in PWM waveform. Moreover, it formulates the possibility of utilizing the classical Preisach model to predict iron losses under PWM excitation.
Research limitations/implications
The approach is still limited in terms of its application at high frequencies. This work may eventually lead toward the accurate prediction of iron loss under PWM excitation in electromagnetic machine design.
Practical implications
The paper provides a simple approach applying the Preisach model for the prediction of iron losses under PWM excitation. The proposed approach does not require additional experimental data beyond B-H loops measured under sinusoidal excitation.
Originality/value
A novel approach is presented to incorporate the frequency dependence into a static inverse Preisach model. The approach extends the ability of the static Preisach model to compute total iron loss under PWM excitation using a weighted Everett function.
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Abdelazeem Hassan Shehata Atyia and Abdelrahman Mohamed Ghanim
The accurate modeling of magnetic hysteresis in electrical steels is important in several electrical and electronic applications. Numerical models have long been known that can…
Abstract
Purpose
The accurate modeling of magnetic hysteresis in electrical steels is important in several electrical and electronic applications. Numerical models have long been known that can correctly reproduce some typical behaviours of these magnetic materials. Among these, the model proposed by Jiles and Atherton must certainly be mentioned. This model is intuitive and fairly easy to implement and identify with relatively few experimental data. Also, for this reason, it has been extensively studied in different formulations. The developments and numerical tests made on this hysteresis model have indicated that it is able to accurately reproduce symmetrical cycles, especially the major loop, but often it fails to reproduce non-symmetrical cycles. This paper aims to show the positive aspects and highlight the defects of the different formulations in predicting the minor loops of electrical steels excited by non-sinusoidal currents.
Design/methodology/approach
The different formulations are applied to different electrical steels, and the data coming from the simulations are compared with those measured experimentally. The direct and inverse Jiles–Atherton models, including the introduction of the dissipative factor approach, are presented, and their limitations are proposed and validated using the measurements of three non-grain-oriented materials. Only the measured major loop is used to identify the parameters of the Jiles–Atherton model. Furthermore, the direct and inverse Jiles–Atherton models were used to simulate the minor loops as well as the hysteresis cycles with direct component (DC) bias excitation. Finally, the simulation results are discussed and compared to measurements for each study case.
Findings
The paper indicates that both the direct and the inverse Jiles–Atherton model formulations provide a good agreement with the experimental data for the major loop representation; nevertheless, both models can not accurately predict the minor loops even when the modification approaches proposed in the literature were implemented.
Originality/value
The Jiles–Atherton model and its modifications are widely discussed in the literature; however, some limitations of the model and its modification in the case of the distorted current waveform are not completely highlighted. Furthermore, this paper contains an original discussion on the accuracy of the prediction of minor loops from distorted current waveforms, including DC bias.
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Sajid Hussain, Firdous Kausar, Ashraf Masood and Jong Hyuk Park
As large‐scale homogeneous networks suffer from high costs of communication, computation, and storage requirements, the heterogeneous sensor networks (HSN) are preferred because…
Abstract
Purpose
As large‐scale homogeneous networks suffer from high costs of communication, computation, and storage requirements, the heterogeneous sensor networks (HSN) are preferred because they provide better performance and security solutions for scalable applications in dynamic environments. Random key pre‐distribution schemes are vulnerable to collusion attacks. The purpose of this paper is to propose an efficient collusion resistant security mechanism for heterogeneous sensor networks.
Design/methodology/approach
The authors consider a heterogeneous sensor network (HSN) consists of a small number of powerful high‐end H‐sensors and a large number of ordinary low‐end L‐sensors. However, homogeneous sensor network (MSN) consists of only L‐sensors. Since the collusion attack on key pre‐distribution scheme mainly takes advantage of the globally applicable keys, which are selected from the same key pool, they update the key ring after initial deployment and generate new key rings by using one‐way hash function on nodes' IDs and initial key rings. Further, in the proposed scheme, every node is authenticated by the BS in order to join the network.
Findings
The analysis of the proposed scheme shows that even if a large number of nodes are compromised, an adversary can only exploit a small number of keys near the compromised nodes, while other keys in the network remain safe.
Originality/value
The proposed key management scheme described in the paper outperforms the previous random key pre‐distribution schemes by: considerably reducing the storage requirement, and providing more resiliency against node capture and collusion attacks.
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Suhail Ahmad Bhat and Mushtaq Ahmad Darzi
The purpose of this paper is to develop a comprehensive integrated model which helps in explaining the impact of Customer Relationship Management (CRM) dimensions (complaint…
Abstract
Purpose
The purpose of this paper is to develop a comprehensive integrated model which helps in explaining the impact of Customer Relationship Management (CRM) dimensions (complaint resolution, customer knowledge, customer empowerment and customer orientation) on customer loyalty and competitive advantage of a bank. The study also explores the mediating role of customer loyalty in the relationship between CRM and competitive advantage in retail banking.
Design/methodology/approach
The research is based on a theoretical model which consists of four CRM dimensions and two exogenous variables. These have been used for establishing the hypotheses to analyze relationships between the variables constituting the CRM model. The data have been collected from 278 customers of a private bank. The data were analyzed using structural equation modeling (SEM). The scale was developed and purified through factor analysis (exploratory and confirmatory factor analysis). SEM was then used to examine the causal relationships and “model fit” of the proposed model.
Findings
The results provide evidence that the four CRM dimensions have a positive effect on customer loyalty and competitive advantage of the bank. Among the CRM dimensions, customer knowledge is most influential of all the dimensions. Furthermore, customer loyalty acts as the mediator in the CRM model between CRM and competitive advantage.
Research limitations/implications
Since, the study involved a single bank and therefore the results should be generalized cautiously. Only four CRM variables were included in the study; additional variables can be introduced in further studies involving different contexts.
Practical implications
The study highlights and supports the need for mangers to devote additional resources toward developing a better CRM system. Therefore, mangers need to think beyond the technological aspects and should focus on these four dimensions, especially customer knowledge, to enhance the loyalty and competitiveness.
Originality/value
The paper investigated hitherto unexplored relationships between customer-centric CRM dimensions instrumental in providing competitive advantage to a bank through mediational analysis. Thus, it contributes to the information on the implementation of CRM practices valuable for banking sector.
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Mirza Mohammad Didarul Alam, Rashed Al Karim and Wardha Habiba
The present study investigates the moderating role of customer trust in customer relationship management (CRM) components and customer loyalty relationships in the context of the…
Abstract
Purpose
The present study investigates the moderating role of customer trust in customer relationship management (CRM) components and customer loyalty relationships in the context of the baking sector in Bangladesh.
Design/methodology/approach
Data were collected through a survey using a structured questionnaire from 350 customers of commercial banks in Bangladesh.
Findings
The key finding is that all CRM components (customer orientation, customer advocacy and customer knowledge) except customer engagement have positive impact on customer loyalty. Moreover, customer trust only moderates the relationship between customer knowledge and customer loyalty, whereas other CRM components and customer loyalty do not moderate by trust.
Originality/value
The findings of the study add to the substantial pool of knowledge on CRM components, customer trust and customer loyalty literature. More specifically, the moderating role of customer trust between customer knowledge and customer loyalty is the novel contribution of this research which will enrich the existing CRM literature particularly in the banking sector of Bangladesh.
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Ghulam Hussain, Mian Sajid Nazir, Muhammad Amir Rashid and Maheen Abdul Sattar
This study aims to examine the direct and indirect effects of supply chain resilience enablers on supply chain disruption orientation per supply chain resilience. It conjointly…
Abstract
Purpose
This study aims to examine the direct and indirect effects of supply chain resilience enablers on supply chain disruption orientation per supply chain resilience. It conjointly examined the moderation of supply chain complexity on resilience enablers and supply chain resilience. It further detailed the conditional indirect effects of supply chain resilience enablers on supply chain disruption orientations via supply chain resilience at varying levels of supply chain complexity.
Design/methodology/approach
This study employed a time-lagged design (three-wave) and self-administered surveys to collect data from the supply chain managers of fast-moving consumer goods firms. A sample of 214 responses was used to test the hypothesized relationships.
Findings
The results showed that supply chain resilience significantly mediated on the relationship between supply chain resilience enablers and supply chain disruption orientation. Further, supply chain complexity positively moderated on supply chain resilience enablers and supply chain resilience. The results also supported the moderated mediated hypothesis.
Research limitations/implications
This study contributes to prevalent theory and practices in the wake of recent disruptions faced by the firms. It persuades the managers to emphasize on structuring resilient supply chain system to recover from the disruptions and accumulate and incorporate learning gained from the disruptions to strengthen the firm's response management system.
Originality/value
This study attempted to explore the underlying antecedents and consequences of supply chain resilience in Pakistan and established boundary condition effects of supply chain complexity on the proposed relationships. This research complemented and extended the conceits of resource-based and contingent resource-based views.
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Syed Saqlain Ul Hassan, Mohammad Azam Hussain and Saima Sajid
The efficient and strong financial system is considered as the backbone of the economy to function properly along with to attract international capital flow, investment and…
Abstract
Purpose
The efficient and strong financial system is considered as the backbone of the economy to function properly along with to attract international capital flow, investment and employment. But, on the other hand, weakness in the financial system will create negative impacts on the economy by sabotaging society’s trust in the financial system. In Pakistan, the key component of the financial sector is the banking sector including conventional and Islamic banking. Pakistan is among the pioneer of the Islamic banking sector, its share of 15.6% deposits in the total banking sector. This paper aims to analyze the effectiveness of anti-money laundering (AML) legislation in the Islamic banking sector of Pakistan.
Design/methodology/approach
The study is doctrinal legal research. The semi-structured interview approach for analysis have been adopted to analyze the materials used in the study to attain the objective. The survey approach was used in critically analyzing the effectiveness of AML laws in conjunction with Islamic banking of Pakistan by incorporating the expert’s views and perceptions. The interviews conducted through electronic media including email, WhatsApp and LinkedIn.
Findings
The findings revealed that the State Bank of Pakistan is playing an active role and bringing stringent updates and regulations from time to time for the enforcement of these legislations. The irony is that these laws are not implemented in a proper way due to a lack of coordination among legislative authorities and the banking sector.
Research limitations/implications
As money laundering is an international recognized offense, the study is based on only the Islamic banking sector of Pakistan. This is a very extensive and contentious matter, and this study is impeding money laundering operations and their analysis to the Islamic banks only.
Practical implications
It is recommended that more efficient laws and regulatory environments are a needed in the Islamic banking sector of Pakistan accompanied by proper and timely implementations of these laws with the joint collaboration of national and international agencies.
Originality/value
This is the first study that incorporated the expert’s opinion from diverse background to analyze the effectiveness of AML legislation with special reference to the Islamic banking sector of Pakistan and contribute significantly in providing greater insight in improving AML legislations in Pakistan.
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Zeerak Waryam Sajid, Shayan Ali Khan, Fazal Hussain, Fahim Ullah, Rao Arsalan Khushnood and Nancy Soliman
Infill materials play a pivotal role in determining buildings’ life cycle costing (LCC) and environmental impacts. International standards prescribe LCC and life cycle assessments…
Abstract
Purpose
Infill materials play a pivotal role in determining buildings’ life cycle costing (LCC) and environmental impacts. International standards prescribe LCC and life cycle assessments (LCA) to assess materials’ economic and environmental sustainability. The existing methods of LCC and LCA are tedious and time-consuming, reducing their practical application. This study sought to integrate LCC and LCA with building information modeling (BIM) to develop a swift and efficient approach for evaluating the life cycle performance of infill materials.
Design/methodology/approach
The BIM model for a case study was prepared using Autodesk Revit®, and the study included four infill materials (lightweight aggregate concrete block (LECA), autoclaved cellular concrete (AAC), concrete masonry and bricks). LCC was conducted using Revit® and Autodesk Insight 360® to estimate costs incurred across different project phases. LCA was conducted using “One Click LCA®,” a BIM-based platform featuring a comprehensive material inventory. Carbon emissions, acidification, and eutrophication were chosen as environmental impact factors for LCA.
Findings
LECA was the preferred choice due to its lower cost and environmental impact. Its lifetime cost of $440,618 was 5.4% lower than bricks’, with 2.8% lower CO2 emissions than AAC’s, which were second-place options, respectively. LECA had 6.4 and 27% lower costs than concrete blocks, and AAC’s carbon emissions were 32 and 58% lower than concrete blocks and bricks, respectively.
Originality/value
BIM has been employed for life cycle analysis in existing literature, but its efficacy in evaluating the lifetime costs and environmental impacts of infill materials remains unexplored. The current study presents a BIM-based approach for conducting LCC and LCA of infill materials, facilitating informed decision-making during the planning phase and promoting sustainable construction practices.
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Muhammad Sajid Nawaz, Saif Ur Rehman Khan, Shahid Hussain and Javed Iqbal
This study aims to identify the developer’s objectives, current state-of-the-art techniques, challenges and performance evaluation metrics, and presents outlines of a…
Abstract
Purpose
This study aims to identify the developer’s objectives, current state-of-the-art techniques, challenges and performance evaluation metrics, and presents outlines of a knowledge-based application programming interfaces (API) recommendation system for the developers. Moreover, the current study intends to classify current state-of-the-art techniques supporting automated API recommendations.
Design/methodology/approach
In this study, the authors have performed a systematic literature review of studies, which have been published between the years 2004–2021 to achieve the targeted research objective. Subsequently, the authors performed the analysis of 35 primary studies.
Findings
The outcomes of this study are: (1) devising a thematic taxonomy based on the identified developers’ challenges, where mashup-oriented APIs and time-consuming process are frequently encountered challenges by the developers; (2) categorizing current state-of-the-art API recommendation techniques (i.e. clustering techniques, data preprocessing techniques, similarity measurements techniques and ranking techniques); (3) designing a taxonomy based on the identified objectives, where accuracy is the most targeted objective in API recommendation context; (4) identifying a list of evaluation metrics employed to assess the performance of the proposed techniques; (5) performing a SWOT analysis on the selected studies; (6) based on the developer’s challenges, objectives and SWOT analysis, presenting outlines of a recommendation system for the developers and (7) delineating several future research dimensions in API recommendations context.
Research limitations/implications
This study provides complete guidance to the new researcher in the context of API recommendations. Also, the researcher can target these objectives (accuracy, response time, method recommendation, compatibility, user requirement-based API, automatic service recommendation and API location) in the future. Moreover, the developers can overcome the identified challenges (including mashup-oriented API, Time-consuming process, learn how to use the API, integrated problem, API method usage location and limited usage of code) in the future by proposing a framework or recommendation system. Furthermore, the classification of current state-of-the-art API recommendation techniques also helps the researchers who wish to work in the future in the context of API recommendation.
Practical implications
This study not only facilitates the researcher but also facilitates the practitioners in several ways. The current study guides the developer in minimizing the development time in terms of selecting relevant APIs rather than following traditional manual selection. Moreover, this study facilitates integrating APIs in a project. Thus, the recommendation system saves the time for developers, and increases their productivity.
Originality/value
API recommendation remains an active area of research in web and mobile-based applications development. The authors believe that this study acts as a useful tool for the interested researchers and practitioners as it will contribute to the body of knowledge in API recommendations context.