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Article
Publication date: 22 February 2021

Reza Sakiani, Abbas Seifi and Reza Ramezani Khorshiddost

There is usually a considerable shortage of resources and a lack of accurate data about the demand amount in a post-disaster situation. This paper aims to model the distribution…

205

Abstract

Purpose

There is usually a considerable shortage of resources and a lack of accurate data about the demand amount in a post-disaster situation. This paper aims to model the distribution and redistribution of relief items. When the new data on demand and resources become available the redistribution of previously delivered items may be necessary due to severe shortages in some locations and surplus inventory in other areas.

Design/methodology/approach

The presented model includes a vehicle routing problem in the first period and some network flow structures for succeeding periods of each run. Thereby, it can produce itineraries and loading plans for each vehicle in all periods when it is run in a rolling horizon manner. The fairness in distribution is sought by minimizing the maximum shortage of commodities among the affected areas while considering operational costs. Besides, equity of welfare in different periods is taken into account.

Findings

The proposed model is evaluated by a realistic case study. The results show that redistribution and multi-period planning can improve efficiency and fairness in supply after the occurrence of a disaster.

Originality/value

This paper proposes an operational model for distribution and redistribution of relief items considering the differences of items characteristics. The model integrates two well-known structures, vehicle routing problem with pickup and delivery and network flow problem to take their advantages. To get more practical results, the model relaxes some simplifying assumptions commonly used in disaster relief studies. Furthermore, the model is used in a realistic case study.

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Article
Publication date: 16 April 2020

Mohammad Mahdi Ershadi and Abbas Seifi

This study aims to differential diagnosis of some diseases using classification methods to support effective medical treatment. For this purpose, different classification methods…

244

Abstract

Purpose

This study aims to differential diagnosis of some diseases using classification methods to support effective medical treatment. For this purpose, different classification methods based on data, experts’ knowledge and both are considered in some cases. Besides, feature reduction and some clustering methods are used to improve their performance.

Design/methodology/approach

First, the performances of classification methods are evaluated for differential diagnosis of different diseases. Then, experts' knowledge is utilized to modify the Bayesian networks' structures. Analyses of the results show that using experts' knowledge is more effective than other algorithms for increasing the accuracy of Bayesian network classification. A total of ten different diseases are used for testing, taken from the Machine Learning Repository datasets of the University of California at Irvine (UCI).

Findings

The proposed method improves both the computation time and accuracy of the classification methods used in this paper. Bayesian networks based on experts' knowledge achieve a maximum average accuracy of 87 percent, with a minimum standard deviation average of 0.04 over the sample datasets among all classification methods.

Practical implications

The proposed methodology can be applied to perform disease differential diagnosis analysis.

Originality/value

This study presents the usefulness of experts' knowledge in the diagnosis while proposing an adopted improvement method for classifications. Besides, the Bayesian network based on experts' knowledge is useful for different diseases neglected by previous papers.

Details

International Journal of Intelligent Computing and Cybernetics, vol. 13 no. 1
Type: Research Article
ISSN: 1756-378X

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Article
Publication date: 2 May 2017

Omid Momen, Akbar Esfahanipour and Abbas Seifi

The purpose of this paper is to develop a prescriptive portfolio selection (PPS) model based on a compromise between the idea of “fast” and “slow” thinking proposed by Kahneman.

457

Abstract

Purpose

The purpose of this paper is to develop a prescriptive portfolio selection (PPS) model based on a compromise between the idea of “fast” and “slow” thinking proposed by Kahneman.

Design/methodology/approach

“Fast” thinking is effortless and comfortable for investors, while “slow” thinking may result in better performance. These two systems are related to the first two types of analysis in the decision theory: descriptive, normative and prescriptive analysis. However, to compromise between “fast” and “slow” thinking, “overconfidence” is used as a weighting parameter. A case study including a sample of 161 active investors in Tehran Stock Exchange (TSE) is provided. Moreover, the feasibility and optimality of the model are discussed.

Findings

Results show that the PPS recommendations are efficient with a shift from the mean-variance efficient frontier; investors prefer PPS portfolios over the advisor recommendations; and investors have no significant preference between PPS and their own expectations.

Research limitations/implications

Two assumptions of this study include: first, investors follow their “fast” system of thinking by themselves. Second, the investors’ “slow” system of thinking is represented by advisor recommendations which are simple expected value of risk and return. Therefore, considering these two assumptions for any application is the main limitation of this study. Moreover, the authors did not have access to more investors in TSE or other financial markets.

Originality/value

This is the first study that includes overconfidence in modeling portfolio selection for the purpose of achieving a portfolio that has a reasonable performance and one that investors are comfortable with.

Details

Qualitative Research in Financial Markets, vol. 9 no. 2
Type: Research Article
ISSN: 1755-4179

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Article
Publication date: 27 June 2020

Abbas Doulani, Nasim Ansari, Seyedeh Zahra Mirezati and Mohammad Karim Saberi

The aim of this study is to identify the status of managing gray literature (GL) in medical science libraries in terms of three dimensions, collection development, organization…

379

Abstract

Purpose

The aim of this study is to identify the status of managing gray literature (GL) in medical science libraries in terms of three dimensions, collection development, organization and dissemination.

Design/methodology/approach

In this survey study, a structured questionnaire was used. The questionnaire consisted of 30 questions and consisted of six sections (demographic characteristics, the use of the term GL, types of GL, collection development, organization and dissemination). In total, 50 librarians from 15 medical science libraries participated in this study. The questionnaires were distributed manually to librarians by visiting libraries. All the librarians filled in the questionnaires. It should be noted that descriptive statistics and Excel and SPSS software were used for data analysis.

Findings

The results of using the term GL showed that 68 per cent of librarians use the source name itself. Most GL in libraries were theses (94 per cent). Moreover, a review of the status of GL collection showed that 60 per cent of libraries had written instructions for providing these resources. A total of 62 per cent of librarians stated that there is a GL selection committee in their library and the librarian is the most important member of the collection department. A total of 40 per cent of libraries were weeding GL. The most common way of obtaining GL was through deposition. The analysis of the status of GL organization indicated that 80 per cent of libraries had GL organization. A total of 90 per cent of libraries had digitized GL, and that librarians played a large role in organizing such resources. Evaluation of the dissemination of GL showed that all libraries have enabled users to access GL. In most libraries, users were only allowed to use GL in the library, and it was not possible to copy GL. Students and faculty members were the most important users of GL. Informing through the library website and the parent organization was the most important way of informing about these resources.

Originality/value

GL is one of the most important resources in medical and non-medical academic libraries. In this study, for the first time, the status of GL management in Iranian libraries of medical sciences was investigated. The results of this study can be useful for policymakers and managers of medical and non-medical libraries.

Details

Collection and Curation, vol. 40 no. 3
Type: Research Article
ISSN: 2514-9326

Keywords

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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 supply…

484

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

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Article
Publication date: 20 September 2011

Mehdi Dehghan and Fatemeh Shakeri

Multi‐point boundary value problems have important roles in the modelling of various problems in physics and engineering. This paper aims to present the solution of ordinary…

481

Abstract

Purpose

Multi‐point boundary value problems have important roles in the modelling of various problems in physics and engineering. This paper aims to present the solution of ordinary differential equations with multi‐point boundary value conditions by means of a semi‐numerical approach which is based on the homotopy analysis method.

Design/methodology/approach

The convergence of the obtained solution is expressed and some typical examples are employed to illustrate validity, effectiveness and flexibility of this procedure. This approach, in contrast to perturbation techniques, is valid even for systems without any small/large parameters and therefore it can be applied more widely than perturbation techniques, especially when there do not exist any small/large quantities.

Findings

Unlike other analytic techniques, this approach provides a convenient way to adjust and control the convergence of approximation series. Some applications will be briefly introduced.

Originality/value

The paper shows how an important boundary value problem is solved with a semi‐analytical method.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 21 no. 7
Type: Research Article
ISSN: 0961-5539

Keywords

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Article
Publication date: 18 August 2023

Md. Farijul Islam, M.M. Mofiz Uddin and Md. Mominur Rahman

This study aims to examine the determinants of retailer social responsibility (RSR) in Old Dhaka City and their impact on RSR practices.

593

Abstract

Purpose

This study aims to examine the determinants of retailer social responsibility (RSR) in Old Dhaka City and their impact on RSR practices.

Design/methodology/approach

A cross-sectional design was used to collect primary data from 180 retailers through a questionnaire survey. The study used partial least squares structural equation modeling to analyze the data and examine the relationships among the determinants of RSR.

Findings

The study found that economic and ethical factors positively and significantly affect RSR practices, while social and environmental factors negatively but not significantly affect RSR practices. Cultural factors were also found to positively and significantly affect RSR practices.

Practical implications

This study provides insights for retailers and policymakers to enhance their RSR practices by considering economic, ethical and cultural factors. The findings also contribute to the existing literature on stakeholder theory by highlighting the importance of considering multiple stakeholders in RSR practices.

Originality/value

This study provides insights into the determinants of RSR in a unique setting in associating stakeholder theory and in Bangladesh, which has received limited attention in the literature on RSR.

Details

Social Responsibility Journal, vol. 20 no. 3
Type: Research Article
ISSN: 1747-1117

Keywords

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Article
Publication date: 28 June 2022

Vahid Mohamad Taghvaee, Mehrab Nodehi, Abbas Assari Arani, Mehrnoosh Rishehri, Shahab Edin Nodehi and Jalil Khodaparast Shirazi

This study aims to develop a price policy for fossil fuel consumption, as it is an effective instrument to manage the demand-side of energy economics.

432

Abstract

Purpose

This study aims to develop a price policy for fossil fuel consumption, as it is an effective instrument to manage the demand-side of energy economics.

Design/methodology/approach

This research estimates the demand elasticities of diesel, gasoline, fuel oil and kerosene by using static, dynamic and error-correction models in log-linear form.

Findings

The findings show that fossil fuel demand responds to price changes less than income changes, as fuel price is inelastic, but income is elastic. In that respect, the impact of price change decreases constantly with increasing energy price, followed by subsidy reform. Subsidy removal and price policy reformation is the UN recommendation for subsidizing countries, including Iran, to reduce fossil fuel consumption, whose intensity depends on the price elasticities.

Practical implications

As a result of this price policy, diesel, gasoline and liquefied petroleum gas prices should increase at least 1.8%–7.3%, 4.4%–6.4% and 7%–8.6%, respectively, and gradually within 2018–2030. The price policy improves all the pillars of sustainable development, including economy, environment and social (health). Overall, such a target can potentially save 3%–29% of diesel, 34%–56% of gasoline and 15%–20% of liquefied petroleum gas, as well as reduce 15%–40% of CO2 emissions annually, and can save potentially more than 510,000 lives annually. Thus, the energy price policy can fundamentally improve sustainability.

Originality/value

The estimated elasticities outline the required prices to decrease the fossil fuels, according to the UN mitigation targets, as price policy recommendation.

Graphical abstract

Details

International Journal of Energy Sector Management, vol. 17 no. 2
Type: Research Article
ISSN: 1750-6220

Keywords

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Article
Publication date: 2 October 2017

M. Mustafa, T. Hayat and A. Alsaedi

The purpose of this paper is to analyze the heat transfer effects on the stretched flow of Oldroyd-B fluid in a rotating frame. Cattaneo–Christov heat conduction model is…

74

Abstract

Purpose

The purpose of this paper is to analyze the heat transfer effects on the stretched flow of Oldroyd-B fluid in a rotating frame. Cattaneo–Christov heat conduction model is considered, which accounts for the influence of thermal relaxation time.

Design/methodology/approach

Based on scale analysis, the usual boundary layer approximations are used to simplify the governing equations. The equations so formed have been reduced to self-similar forms by similarity transformations. A powerful analytic approach, namely, homotopy analysis method (HAM), has been applied to present uniformly convergent solutions for velocity and temperature profiles.

Findings

Suitable values of the so-called auxiliary parameter in HAM are obtained by plotting h-curves. The results show that boundary layer thickness has an inverse relation with fluid relaxation time. The rotation parameter gives resistance to the momentum transport and enhances fluid temperature. Thermal boundary layer becomes thinner when larger values of thermal relaxation time are chosen.

Originality/value

To the authors’ knowledge, this is the first attempt to study the three-dimensional rotating flow and heat transfer of Oldroyd-B fluid.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 27 no. 10
Type: Research Article
ISSN: 0961-5539

Keywords

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Article
Publication date: 24 August 2018

Anika Meyer and Ina Fourie

The purpose of this paper is to report on an exploratory study of third-year architecture students’ information behaviour. It focusses on information activities, personal…

1006

Abstract

Purpose

The purpose of this paper is to report on an exploratory study of third-year architecture students’ information behaviour. It focusses on information activities, personal experience, resource usage, preferences in working individually or collaboratively, preferences for information resources inspiring creativity and physical spaces to be creative.

Design/methodology/approach

It was a mixed methods study with a strongly qualitative component and limited descriptive quantitative data. Data were collected in October 2016 at a South African university using individual self-administered questionnaires and semi-structured individual interviews; 19 out of 60 (response rate 32 per cent) third-year architecture students doing a design project participated.

Findings

Creativity is important in architecture projects, as is information resources in stimulating creativity. Students preferred to work individually during their design projects; at times collaboration was needed for idea generation. Information activities included: information gathering, encountering, use and sharing. A range of theoretical, technical, artistic and practical skills and knowledge must be integrated to produce creative outcomes, in addition, to information searching and information usage. Factual information is also required. Students can benefit from a supportive information rich creative space (physical or virtual).

Research limitations/implications

The study was conducted at only one institution with a small number of participants. Although generalisation of findings is not possible, issues for further research can be noted.

Practical implications

Designers of physical and virtual creative spaces must take into account different facets of information behaviour and the information resources and services required during creative information-seeking activities.

Originality/value

Although there is literature on information behaviour and creativity, the authors could not find any that explores architecture students’ information behaviour in academic spaces of creativity.

Details

Aslib Journal of Information Management, vol. 70 no. 4
Type: Research Article
ISSN: 2050-3806

Keywords

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