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Article
Publication date: 8 November 2019

Mohsen Karimi, Mohammad Pichan, Mehdi Sadri and Seyed Morteza Seyedjafari

This paper aims to investigate an improved control method and digital signal processor-based (DSP-based) digital implementation of three-phase standalone inverter. The…

Abstract

Purpose

This paper aims to investigate an improved control method and digital signal processor-based (DSP-based) digital implementation of three-phase standalone inverter. The proposed method is performance developed of the proportional-resonant controller (PRC) with harmonic injection technique, aiming to improve load voltages quality under different loads, especially nonlinear loads. The advanced proposed multi-loop controller is consisted of current harmonic loops for suppressing odd harmonic, which are analyzed in discrete-time domain. Besides, the voltage loop is also used to compensate the output capacitor voltage.

Design/methodology/approach

The proposed method can effectively enlarge output voltage stability with low total harmonics distortion and improve the dynamic transient response. The other advantage of the proposed PRC is the injection of the selective harmonic without any additional calculation compensator.

Findings

The method is given the opportunity to be controlled exactly all harmful outputs with high-quality voltage referenced of the standalone inverter. The proposed method is implemented using a DSP processor (TMS320F28335) and is verified on the 10 kVA three-phase standalone inverter prototype.

Originality/value

The proposed method is performance developed of the PRC with harmonic injection technique, aiming to improve load voltages quality under different loads, especially nonlinear loads.

Details

World Journal of Engineering, vol. 16 no. 6
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 3 December 2018

Mohsen Karimi, Mohammad Pichan, Adib Abrishamifar and Mehdi Fazeli

This paper aims to propose a novel integrated control method (ICM) for high-power-density non-inverting interleaved buck-boost DC-DC converter. To achieve high power…

Abstract

Purpose

This paper aims to propose a novel integrated control method (ICM) for high-power-density non-inverting interleaved buck-boost DC-DC converter. To achieve high power conversion by conventional single phase DC-DC converter, inductor value must be increased. This converter is not suitable for industrial and high-power applications as large inductor value will increase the inductor current ripple. Thus, two-phase non-inverting interleaved buck-boost DC-DC converter is proposed.

Design/methodology/approach

The proposed ICM approach is based on the theory of integrated dynamic modeling of continuous conduction mode (CCM), discontinuous conduction mode and synchronizing parallel operation mode. In addition, it involves the output voltage controller with inner current loop (inductor current controller) to make a fair balancing between two stages. To ensure fast transient performance, proposed digital ICM is implemented based on a TMS320F28335 digital signal microprocessor.

Findings

The results verify the effectiveness of the proposed ICM algorithm to achieve high voltage regulating (under 0.01 per cent), very low inductor current ripple (for boost is 1.96 per cent, for buck is 1.1) and fair input current balance between two stages (unbalancing current less than 0.5A).

Originality/value

The proposed new ICM design procedure is developed satisfactorily to ensure fast transient response even under high load variation and the solving R right-half-plane HP zeros of the CCM. In addition, the proposed method can equally divide the input current of stages and stable different parallel operation modes with large input voltage variations.

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Article
Publication date: 16 July 2021

Roghayeh Chenary, Akram Karimi-Shahanjarini, Saeid Bashirian, Ghodratollah Roshanaei, Ali Akbar Fazaeli and Mohsen Jalilian

The high prevalence of hypertension is a significant concern worldwide. A decrease in salt intake is a well-known strategy to control hypertension and reduce the risk of…

Abstract

Purpose

The high prevalence of hypertension is a significant concern worldwide. A decrease in salt intake is a well-known strategy to control hypertension and reduce the risk of cardiovascular diseases. Little is known about the factors influencing salt intake behaviors in settings such as Iran where consumption of salt is higher than the recommended amount. The purpose of this study was to find out what factors affect three salt intake behaviors among women: adding salt when cooking, adding salt to prepared food at the table and purchasing salty foods.

Design/methodology/approach

A community-wide cross-sectional survey of 516 women was conducted in Ilam, Iran. Participants were recruited using the cluster random sampling method. The survey included behaviors and variables of an expanded theory of planned behavior. The hypothesized relationships were investigated using structural equation modeling.

Findings

Perceived behavioral control (PBC) (p < 0.001) and habit (p = 0.01) appeared to be significant factors of adding salt when cooking. Determinants of adding salt to food at the table were intention (p < 0.001), PBC (p < 0.001), habit (p < 0.001). Also, PBC (p < 0.001), intention (p < 0.001), habit (p < 0.001) were identified as predictors of the purchase of salty foods. The results did not support the moderating role of Hedonic feeling to salt on the relation between intention and behaviors.

Originality/value

This study would be applicable to develop salt reduction interventions. Because altering the hedonic response to food is difficult, the lack of its moderating role could be a promising finding for developing salt reduction interventions.

Details

Nutrition & Food Science , vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0034-6659

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Article
Publication date: 16 October 2018

Vahid Kayvanfar, S.M. Moattar Husseini, Zhang NengSheng, Behrooz Karimi and Mohsen S. Sajadieh

This paper aims to optimize the interactions of businesses located within industrial clusters (ICs) by using a supply-demand hub in ICs (SDHIC) as a conjoint provider of…

Abstract

Purpose

This paper aims to optimize the interactions of businesses located within industrial clusters (ICs) by using a supply-demand hub in ICs (SDHIC) as a conjoint provider of logistics and depository facilities for small- and medium-sized enterprises (SMEs) as producers, where all of these interactions are under supervision of a third-party logistics provider (3PL).

Design/methodology/approach

To evaluate the values of SDHIC, three mathematical models are proposed, optimally solved via GAMS and then compared. Also, a “linear relaxation-based heuristic” procedure is proposed to yield a feasible initial solution within a significant shorter computational time. To illustrate the values of SDHIC, comprehensive calculations over a case study and generated sets of instances are conducted, including several sensitivity analysis.

Findings

The experimental results demonstrate the efficiency of SDHIC for SMEs via combining batches and integrating the holding space of inventories, while the outcomes of the case study are aligned with those obtained from random sample examples, which confirms the trueness of used parameters and reveals the applicability of using SDHIC in real world. Finally, several interesting managerial implications for practitioners are extracted and presented.

Practical implications

Some of the managerial and practical implications are optimizing interactions of businesses involved in a supply chain of an IC containing some customers, suppliers and manufacturers and rectifying the present noteworthy gaps pertaining to the previously published research via using real assumptions and merging upstream and downstream of the supply chain through centralizing on storage of raw materials (supply echelon) and finished products (demand echelon) at the same place simultaneously to challenge a classic concept in which supply and demand echelons were being separately planned regarding their inventory management and logistics activities and showing the positive consequences of such challenge, showing the performance improvement of the proposed model compared to the classic model, by increasing the storing cost of raw materials and finished products, considering some disadvantages of using SDHIC and showing the usefulness of SDHIC in total, presenting some applied findings according to the obtained results of sensitivity analysis.

Originality/value

The key contributions of this paper to the literature are suggesting a new applied mathematical methodology to the supply chain (SC) of ICs by means of a conjoint provider of warehousing activities called SDHIC, comparing the new proposed model with the two classic ones and showing the proposed model’s dominancy, showing the helpful outcomes of collaborating 3PL with the SMEs in a cluster, proposing a “linear relaxation-based heuristic” procedure to yield a feasible initial solution within a significant shorter computational time and minimizing total supply chain costs of such IC by optimum application of facilities, lands and labor.

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Article
Publication date: 8 May 2017

Mahdi Rezaei, Mohsen Akbarpour Shirazi and Behrooz Karimi

The purpose of this paper is to develop an Internet of Things (IoT)-based framework for supply chain (SC) performance measurement and real-time decision alignment. The…

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Abstract

Purpose

The purpose of this paper is to develop an Internet of Things (IoT)-based framework for supply chain (SC) performance measurement and real-time decision alignment. The aims of the proposed model are to optimize the performance indicator based on integrated supply chain operations reference metrics.

Design/methodology/approach

The SC multi-dimensional structure is modeled by multi-objective optimization methods. The operational presented model considers important SC features thoroughly such as multi-echelons, several suppliers, several manufacturers and several products during multiple periods. A multi-objective mathematical programming model is then developed to yield the operational decisions with Pareto efficient performance values and solved using a well-known meta-heuristic algorithm, i.e., non-dominated sorting genetic algorithm II. Afterward, Technique for Order of Preference by Similarity to Ideal Solution method is used to determine the best operational solution based on the strategic decision maker’s idea.

Findings

This paper proposes a dynamic integrated solution for three main problems: strategic decisions in high level, operational decisions in low level and alignment of these two decision levels.

Originality/value

The authors propose a human intelligence-based process for high level decision and machine intelligence-based decision support systems for low level decision using a novel approach. High level and low level decisions are aligned by a machine intelligence model as well. The presented framework is based on change detection, event driven planning and real-time decision alignment.

Details

Industrial Management & Data Systems, vol. 117 no. 4
Type: Research Article
ISSN: 0263-5577

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Article
Publication date: 17 May 2021

Amin Zaheri, Majid Rafiee and Vahid Kayvanfar

This paper aims to study the impact of existence and lack of discount on the relationships between one manufacturer and one retailer under the cooperative and the…

Abstract

Purpose

This paper aims to study the impact of existence and lack of discount on the relationships between one manufacturer and one retailer under the cooperative and the non-cooperative games and the members’ profits are compared.

Design/methodology/approach

In the first approach, the manufacturer’s price function is constant, and in the second approach, this price function is a decreasing function with respect to lot size. These approaches are modeled through three games structure, including two Stackelberg games and one cooperative game.

Findings

Some numerical instances comprising sensitivity analysis are provided, and then the members’ profits in different scenarios are compared. This paper reveals that in the presented models, whether the members are inclined to change their profits.

Practical implications

This paper presents a tool of decision-making for the type of relationships of members in two different circumstances, and an approach is also presented to maximize the members’ profit.

Originality/value

In this paper, the relationships between one manufacturer and one retailer are studied under six different circumstances, where pricing, cooperative advertising and inventory cost are considered simultaneously. Also, a different model is presented to make a balance in individual profits and gain more profit for each member compared to the cooperative and non-cooperative game.

Details

Journal of Modelling in Management, vol. 16 no. 4
Type: Research Article
ISSN: 1746-5664

Keywords

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Article
Publication date: 13 December 2017

Vahid Kayvanfar, Mohsen S. Sajadieh, S.M. Moattar Husseini and Behrooz Karimi

In this paper, a multi-objective multi-echelon supply-distribution model is proposed to optimize interactions of entities located within an Industrial Cluster (IC…

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301

Abstract

Purpose

In this paper, a multi-objective multi-echelon supply-distribution model is proposed to optimize interactions of entities located within an Industrial Cluster (IC) including small- and medium-sized enterprises (SMEs), using a third-party logistics provider (3PL)-managed supply-demand hub in industrial cluster (SDHIC) as a specific public provider of warehousing and logistics services.

Design/methodology/approach

The three considered objectives are minimizing the total logistics costs, maximizing the rate of demand satisfaction and maximizing the quality of delivery. Because some parameters such as “demand of customers” are naturally fuzzy because of incompleteness and/or inaccessibility of the needed information, the triangular fuzzy number is applied for all fuzzy parameters to handle this difficulty. The proposed model is primarily changed into a correspondent supplementary crisp model. To solve such a model, a revised multi-choice goal programming (RMCGP) approach is then used with the purpose of finding a compromise solution.

Findings

Experimental results demonstrate that all enterprises involved in such a supply chain benefit with several advantages using SDHIC by consolidating shipments and merging the storage space of inventories. The applicability of the presented model is shown by conducting these experiments over an applied industrial case study.

Originality/value

The main contributions of this research are proposing a practical mathematical approach to the supply chain of ICs using a specific public warehouse managed by a 3PL, called SDHIC, bridging the existing gaps with respect to the already published researches in this area by applying real-world assumptions such as uncertainty; optimizing the interactions of involved entities in the supply chain of an IC, comprising suppliers, SMEs as manufacturers and customers; minimizing the total incurred logistics costs to such a system through optimum usage of lands, facilities, labors, etc. and boosting the satisfaction of customers through maximizing the service level criteria, illustrating the positive consequences of cooperation of 3PL with the SMEs/manufacturers in an IC, showing the applicability of the adopted approach by implementing it on an applied industrial instance.

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Article
Publication date: 21 September 2018

Mohsen Sadeghi-Dastaki and Abbas Afrazeh

Human resources are one of the most important and effective elements for companies. In other words, employees are a competitive advantage. This issue is more vital in the…

Abstract

Purpose

Human resources are one of the most important and effective elements for companies. In other words, employees are a competitive advantage. This issue is more vital in the supply chains and production systems, because of high need for manpower in the different specification. Therefore, manpower planning is an important, essential and complex task. The purpose of this paper is to present a manpower planning model for production departments. The authors consider workforce with individual and hierarchical skills with skill substitution in the planning. Assuming workforce demand as a factor of uncertainty, a two-stage stochastic model is proposed.

Design/methodology/approach

To solve the proposed mixed-integer model in the real-world cases and large-scale problems, a Benders’ decomposition algorithm is introduced. Some test instances are solved, with scenarios generated by Monte Carlo method. For some test instances, to find the number of suitable scenarios, the authors use the sample average approximation method and to generate scenarios, the authors use Latin hypercube sampling method.

Findings

The results show a reasonable performance in terms of both quality and solution time. Finally, the paper concludes with some analysis of the results and suggestions for further research.

Originality/value

Researchers have attracted to other uncertainty factors such as costs and products demand in the literature, and have little attention to workforce demand as an uncertainty factor. Furthermore, most of the time, researchers assume that there is no difference between the education level and skill, while they are not necessarily equivalent. Hence, this paper enters these elements into decision making.

Details

International Journal of Intelligent Computing and Cybernetics, vol. 11 no. 4
Type: Research Article
ISSN: 1756-378X

Keywords

Content available
Article
Publication date: 14 February 2020

Nima Golghamat Raad and Mohsen Akbarpour Shirazi

This research proposes a framework by which universities can define and implement projects that transform them into entrepreneurial universities. The framework helps…

Abstract

Purpose

This research proposes a framework by which universities can define and implement projects that transform them into entrepreneurial universities. The framework helps decision-makers identify suitable goals and strategies, gather a list of projects to fulfill the goals and strategies and prioritize the projects and form a portfolio.

Design/methodology/approach

In the proposed framework, importance–performance matrix, hierarchical strategic planning, Delphi technique, DEMATEL-based ANP and a multi-objective model are used. The mathematical model consists of four objective functions including efficiency, quality and balance maximization and also cost and risk minimization. The proposed framework is applied to Amirkabir University of Technology, Tehran, Iran, and the results are brought in this paper.

Findings

The output of the proposed framework is a portfolio of projects that aims to transform a traditional university into a third-generation one. Although the final portfolio must be customized for different universities, the proposed steps of the framework can be helpful for almost all cases.

Originality/value

The suggested framework is unique and uses both qualitative and quantitative techniques for project portfolio selection.

Details

Journal of Industry-University Collaboration, vol. 2 no. 1
Type: Research Article
ISSN: 2631-357X

Keywords

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Article
Publication date: 11 October 2019

Mohsen Shafie Nikabadi and Delshad Hoseini

The production of a good or service requires that the supplier performs a wide range of activities. Many companies are trying to fit outsourcing with the dimensions of…

Abstract

Purpose

The production of a good or service requires that the supplier performs a wide range of activities. Many companies are trying to fit outsourcing with the dimensions of their organization. Outsourcing is increasingly being used among Iranian companies in the field of the electric power industry. Human resources are among the factors that consider outsourcing as an obstacle for their growth because staffs declare that the development of outsourcing is a serious threat for unemployment of them and ultimately expulsion from work. Thus, this study surveys the dynamic effects of human resources and work experience on outsourcing decisions. This paper aims to propose a model for dynamic strategic outsourcing focusing on human resource and work experience.

Design/methodology/approach

Presenting a model for strategic outsourcing can help organizations to resolve their outsourcing problems. The data needed for examining the dynamic impact of human resources and work experience on outsourcing have been compiled using library and field studies. The method used in this study is an integrated approach, so the model could consider the general effects of manpower and present a systematic view. After interviewing with experts in power industry, the causal relationships of the variables were determined, and a dynamic model based on the applications of the dynamic system was developed in VENSIM software. The research model will be completed in a three-year period (2016-2019) in the power industry of Iran.

Findings

For completing projects in an organization, cooperation between internal employees and external contractors is needed; thus, results based on both external contractors and internal staff have shown that outsourcing through working of a number of contractors will be more effective than frequent use of one contractor. On the other hand, improving the quality of projects could be done by training new employees using skilled and expert employees.

Originality/value

Existence of one-dimensional models (only with qualitative factors or only with quantitative factors) in the context of outsourcing in the past studies has prompted to study different types of factors together as a dynamic model. This paper presents a quantitative and qualitative model in the field of strategic outsourcing with emphasis on human resources and work experience. In the past studies, there was no way to formulate the qualitative factors, and they simply used the data from the organization, and the only formulation in their works was based on quantitative factors. But in this study, both factors with dynamic modeling have been formulated.

Details

Kybernetes, vol. 49 no. 9
Type: Research Article
ISSN: 0368-492X

Keywords

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