Original Article
stochastic/Probabilistic/fuzzy/dynamic modeling
Ali Sahleh; Maziar Salahi; Sadegh Eskandari
Abstract
Purpose: The aim of this paper is to present an enhanced variant of Twin Parametric-Margin Support Vector Machine (TPMSVM) that improves classification performance.Methodology: By replacing a variable in the objective function, we keep the samples of one class farther from the parametric margin hyperplane ...
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Purpose: The aim of this paper is to present an enhanced variant of Twin Parametric-Margin Support Vector Machine (TPMSVM) that improves classification performance.Methodology: By replacing a variable in the objective function, we keep the samples of one class farther from the parametric margin hyperplane of the other class.Findings: The enhanced model is convex for both linear and nonlinear cases. Also, numerical experiments on UCI datasets show that the enhanced model performs better compared to two similar models for both linear and nonlinear cases.Originality/Value: The previous studies of TPMSVM that increased the accuracy through approaches such as assigning weights to data sample, converting it into an unconstrained model and adding a new term in the objective function, did not guarantee that all samples will be far and on the negative side of the margin hyperplane. However, this study provides an approach to overcome this disadvantage of TPMSVM.
Original Article
Multi-Attribute Decision Making
Mahsima Rasi; Hossein Mohammadi Dolat-Abadi
Abstract
Purpose: This research provides a framework for identifying the core competencies and consequently the competitive advantage of small and medium-sized manufacturing organizations in conditions of fuzzy uncertainty.Methodology: This research ranks of the core competencies using the group fuzzy TOPSIS ...
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Purpose: This research provides a framework for identifying the core competencies and consequently the competitive advantage of small and medium-sized manufacturing organizations in conditions of fuzzy uncertainty.Methodology: This research ranks of the core competencies using the group fuzzy TOPSIS method, which is a mathematical model.Findings: Research findings show that the core competencies of customer services and advertising are considered as a "competitive advantage" in small and medium-sized manufacturing organizations.Originality/Value: To extract the core competencies, the review conducted showed that the previous models ignore the resource-based condition. Moreover, only four main factors including the value creation, uniqueness, irreplaceability, and imitation are considered for screening the core competencies under competitive condition. Taking a different viewpoint, the framework proposed in this study not only encompass the resource based factors but also it covers the market base condition to identify the core competencies. Therefore, in addition to the four above-mentioned factors for screening core competencies, two more factors including the new market creation and scope of application are considered in this research. Also, as a novel application, a group fuzzy TOPSIS method has been developed to identify the core competencies under resource-based and market-based conditions.
Original Article
Multi-Attribute Decision Making
Ali Mohaghar; Rohollah Ghasemi; Hossein Toosi; Morteza Sheykhizadeh
Abstract
Purpose: The purpose of this study is to provide a model to explain the functions of the Project Management Office (PMO) of City Knowledge (CK) and prioritize their functions based on the importance-performance status.Methodology: The method of this research, In terms of purpose, is functional. In terms ...
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Purpose: The purpose of this study is to provide a model to explain the functions of the Project Management Office (PMO) of City Knowledge (CK) and prioritize their functions based on the importance-performance status.Methodology: The method of this research, In terms of purpose, is functional. In terms of data collection tools, it is descriptive (non-experimental). According to comprehensive literature review regarding to PMO functions, 28 main functions of the CK are identified. Questionnaires are designed and distributed among managers, consultants, facilitators and senior experts of City of Knowledge after content validity and reliability. The data are analyzed using structural equation modeling after measuring the construct validity by exploratory factor analysis. Then the best-worst method is used to prioritize the functions and sub-functions of the model. Then, the performance of each functions is obtained by conducting a survey of experts in the PMO of City of Knowledge. Finally, the functions of the PMO are prioritized using the importance‐performance analysis.Findings: Based on the research findings, 7 functions with 28 sub-functions explain the conceptual model of the research. Also, based on the findings of the importance‐performance analysis , design and documentation of project management system in the form of process diagrams, procedures and instructions, uniform formats and standard formats, transparency and clarity of information provided in project planning and organization, providing training services in the field of concepts Processes-Methods and tools of project management, design and development and deployment of project management information systems in the organization, participation in evaluating the performance of project managers, and project management teams are the first priority of improvemen.Originality/Value: In this study, a model for assessing the prioritize of functions of the PMO to create an innovation center is presented. The proposed framework could be a good guideline for universities' policymakers to proceed with development projects and be a suitable model for others to benchmark development plans.
original-application paper
Multi-Attribute Decision Making
Seyyed Ali Delbari; Alireza Davoodi; Niloofar Firozeh
Abstract
Purpose: The purpose of this research is to identify and prioritize international markets entry strategies in plastics industry.Methodology: The research method of the study is explorative-descriptive and its statistical population includes managers and officers working in small and medium-sized enterprises ...
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Purpose: The purpose of this research is to identify and prioritize international markets entry strategies in plastics industry.Methodology: The research method of the study is explorative-descriptive and its statistical population includes managers and officers working in small and medium-sized enterprises in the plastic industry, which are the members of the Bojnord Chamber of Commerce, Industries, and Mines. The sampling method of the study consists of snowballing sampling and purposive sampling, and the sample size is equal to 19 experts. Data collection instrument was questionnaire, which its validity and reliability were confirmed using content validity ratio and inconsistency ratio mechanism, respectively. To analyze data, Analytic Hierarchy Process (AHP) technique was used.Findings: The findings indicate that international markets entry strategies in plastics industry consists of seven strategies, including export, license, management contract, contract manufacturing, turnkey operation, foreign direct investment and strategic alliances, and criteria to select these strategies include four categories of factors related to host country, factors related to product, factors related to company, and factors related to home country. Furthermore, the research findings indicate that the most important criterion to select international markets entry strategies is factors related to company and the best international markets entry strategy is export.Originality/Value: The findings of this research help managers to evaluate, prioritize, and select international markets entry strategies using AHP technique in an effective and efficient manner.
original-application paper
Data Envelopment Analyses
Mohammad Khodabakhshi; Zahra Cheraghali
Abstract
Purpose: Due to the importance of productivity index in the economy, in this article we will discuss the different approaches that are used to measure partial and total factor productivity.Methodology: In all economic and social organizations and systems, the concept of productivity is very important ...
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Purpose: Due to the importance of productivity index in the economy, in this article we will discuss the different approaches that are used to measure partial and total factor productivity.Methodology: In all economic and social organizations and systems, the concept of productivity is very important and is examined using different approaches. Without the goal of productivity, no business will find a suitable direction, and without measuring productivity, there will be no control over business. Measurement is the first step towards control and ultimately improvement. Productivity can be divided into two categories, partial and total factor productivity. Total factor productivity in the economy has a significant impact on increasing GDP growth.Findings: According to the results obtained for the Malmquist index of the industrial sector in 2011, the productivity growth of total factor productivity has been desirable, but productivity in the mining sector has had the greatest decrease. The productivity growth of total factor productivity of the economy in 2011 is almost uniform.Originality/Value: By using the real data of Iran in 2011 calculate partial and total factor productivity with different approaches.
Original Article
Data Envelopment Analyses
Mojtaba Karimi Pashaki; Mahnaz Ahadzadeh Namin
Abstract
Purpose: For managers, investors and creditors, it is important to be aware of the continuity of the company. To this end, financial researchers are looking for effective methods to evaluate the company's performance and predict the continuation of its activities in the coming years.Methodology: In previous ...
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Purpose: For managers, investors and creditors, it is important to be aware of the continuity of the company. To this end, financial researchers are looking for effective methods to evaluate the company's performance and predict the continuation of its activities in the coming years.Methodology: In previous research, the standard data envelopment analysis model has been used to predict corporate bankruptcy. The present study aims to provide a model of data envelopment analysis with semi-positive and negative indicators to predict the bankruptcy of companies operating in the Tehran Stock Exchange. The companies listed on the Tehran Stock Exchange constitute the statistical population of the research. To achieve this goal, a sample consisting of 40 non-bankrupt companies and 20 bankrupt companies in the years 1393 to 1397 were selected. The criterion for selecting bankrupt companies is Article 141 of the Commercial Code.Findings: To combine tax ratios that have a more significant correlation with the financial situation of the company, the combined approach of gray relationship analysis and two-level data envelopment analysis has been used.Originality/Value: First, a two-level data envelopment analysis model for semi-positive and negative indices will be developed, then the correct prediction of bankruptcy with its absence will be examined using the results of the proposed model.
Original Article
Data Envelopment Analyses
Mohammad Afzalinejad; Neda Afzalinejad
Abstract
Purpose: The paper addresses the star network structures with centralized management and provides models for evaluating the performance of such structures. Despite the wide range of applications and importance, such structures have not been studied in data envelopment analysis before.Methodology: The ...
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Purpose: The paper addresses the star network structures with centralized management and provides models for evaluating the performance of such structures. Despite the wide range of applications and importance, such structures have not been studied in data envelopment analysis before.Methodology: The Data Envelopment Analysis (DEA) method is used for modeling the problem, and a two-level method for efficiency evaluation is proposed.Findings: The proposed models are developed in both multiplicative and envelopment forms. The required formulas for efficiency decomposition and benchmarking are provided. Some results are proved by mathematical discussions and numerical experimentation.Originality/Value: The star structure is seen in many real-world applications. A new method for modelling and evaluation of such structures is introduced and established. The proposed technique, discussions and analytical examinations have a significant contribution to the field of data envelopment analysis and its applications.
original-application paper
Data Envelopment Analyses
Gholamreza Panahandeh Khojin; Abbas Toloie Ashlaghi; Mohamad Ali Afshar Kazmi
Abstract
The purpose of this study is to combine two methods of data envelopment analysis and neural network in order to provide an optimal model for ranking inefficiency factors in the Iranian banking industry. First, through the study of theoretical foundations and interviews with banking experts, efficiency ...
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The purpose of this study is to combine two methods of data envelopment analysis and neural network in order to provide an optimal model for ranking inefficiency factors in the Iranian banking industry. First, through the study of theoretical foundations and interviews with banking experts, efficiency evaluation indicators in the banking industry were identified and finalized. In order to evaluate the efficiency of the units in the statistical population of the study, data envelopment analysis technique was used, especially the modified goal programming data envelopment analysis model, which was identified from 32 managements, 3 efficient managements and 29 inefficient managements. Then, the branches of inefficient management were evaluated and using the information of inefficient branches, the neural network matrix was prepared to identify the causes of inefficiency and the results were analyzed with different neural network models. The model with the lowest mean square error will be selected as the optimal model to determine the inefficiency factors. As a result, the self-organized mapping model with hyperbolic tangent transfer function and 0.9 momentum training rule was selected. By analyzing the sensitivity of this method, the indicators of provincial liquidity share, personnel distribution and operating costs were selected as the most important factors of inefficiency.
Original Article
Data Envelopment Analyses
Zeynab Latifi; Neda Pouyan
Abstract
Purpose: Data Envelopment Analysis, one of the keys subfields in mathematical planning, has found a prominent role in evaluating the efficiency of decision making units in various fields. Methodology: In this research, after analysis and initial processing, based on studies, a parametric and efficient ...
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Purpose: Data Envelopment Analysis, one of the keys subfields in mathematical planning, has found a prominent role in evaluating the efficiency of decision making units in various fields. Methodology: In this research, after analysis and initial processing, based on studies, a parametric and efficient method for ranking intuitionistic fuzzy numbers is selected and proposed. The correctness of the performance of the selected method is obvious due to its formulation in linear structures. The developed model of data envelopment analysis, its mathematical formulation by CCR and IO-BCC methods are expressed in terms of governing the model structure and its implementation approach. A case study is presented to determine the factors affecting safety performance using the model. Based on previous theoretical studies and opinions of experts in the field of safety, the most important influencing factors (work pressure and perception of the supervisors' safety as inputs) and (the rate of physical and mental injuries and unsafe accidents as outputs) were selected. In addition to ranking the units, sensitivity analysis was performed in CCR and IO-BCC methods to rank the specified indicators in the inputs and outputs, and the results have been compared.Findings: The results of the data envelopment analysis model with intuitionistic fuzzy data showed that with increasing k, the number of efficient units increases. On the other hand, in CCR and IO-BCC methods, the lowest and highest efficiencies belong to the pessimistic view (k = 0) and the balanced view (k = 0.5), respectively. Sensitivity analysis also showed that, in CCR and IO-BCC methods, the work pressure is the most safety factor affecting the efficiency results.Originality/Value: Using a Data Envelopment Analysis model with intuitionistic fuzzy data to evaluate the performance of construction sites from a safety perspective can provide significantly better results. Because in the real world, there is uncertainty, and intuitionistic fuzzy data, due to the concept of belonging, non-belonging, and suspicion in the view of decision-makers simultaneously and in data reporting, is of particular importance.
Original Article
Pegah Farhangian; Hadi Mokhtari
Abstract
Purpose: The classic model of economic order quantity was introduced several decades ago to reduce inventory costs in companies and has since been widely used in various areas of inventory control. In recent years, researchers have developed various aspects of the EOQ model; Because the classic EOQ model ...
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Purpose: The classic model of economic order quantity was introduced several decades ago to reduce inventory costs in companies and has since been widely used in various areas of inventory control. In recent years, researchers have developed various aspects of the EOQ model; Because the classic EOQ model does not take into account many important parameters in the real world. The purpose of this paper is to develop a classic EOQ model in order to operationalize and realize the assumptions in the space of simultaneous orders with imperfect quality items.Methodology: In this research, a mathematical modeling is developed for the imperfect inventory system as well as the simultaneous ordering requirement. Finally, a numerical example is provided along with the analysis of the results.Findings: The results show that changing the screening rate can have a significant effect on reducing or increasing costs. This cost effect is due to the cost of maintaining items of poor quality until the end of the inspection period. The faster the screening operation and the faster the defective items are removed from the system, the lower the cost.Originality/Value: In classic models, it is assumed that items of appropriate quality are ordered. In fact, due to the unstable quality of the production process, improper transportation, corruption or other factors, the presence of defective items is inevitable. In the proposed EOQ inventory system, these items are separated by 100% inspection of the consignment, and then these isolated items are sold in a package at a discounted price. Also, in order to reduce the fixed costs of ordering and shipping, the policy of simultaneous ordering has been used for all product categories, which has a high efficiency in reducing costs.