Ahmad Ebrahimi; laya olfat; Maghsood Amiri; Mohammad Taghi Taghavifard
Abstract
The current research has considered the design of the four-level supply chain of perishable goods, including manufacturing factories, distribution centers, wholesalers, and retailers, in conditions of uncertainty in important parameters. The aim is to make strategic and tactical decisions, including ...
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The current research has considered the design of the four-level supply chain of perishable goods, including manufacturing factories, distribution centers, wholesalers, and retailers, in conditions of uncertainty in important parameters. The aim is to make strategic and tactical decisions, including the location, number, and size of distribution centers and wholesalers, stock levels in stocking centers, determining the flow of goods between facilities at different supply chain levels, and choosing the type of means of transporting goods between facilities. This is achieved through a three-objective mathematical model. The goals include minimizing the expected total cost in the supply chain, achieving the shortest travel time of goods in the chain, and at the same time minimizing the amount of deviation from customer demand. The presented model tries to pay attention to environmental uncertainty and consider different operational scenarios, as well as the possible approach in important parameters. This takes into account the product life cycle, the different rate of spoilage of the goods in different storage facilities, the different capacity of the facilities in different scenarios, and considering different methods of product transportation with different rates of product spoilage. All of this aims to cover the lack of previous research in the field of perishable goods supply chain design. Considering the multi-objective nature of the model and the need to create flexibility in decision-making for decision-makers, this research uses Normal Boundary Intersection (NBI), which allows decision-makers to choose the most optimal solution according to the importance of different goals. GAMS 24 software and MILP solver were used to solve the mathematical model.
Materials and Methods
This study presents a multiobjective model for designing a four-echelon supply chain (SC) in the strategic and tactical levels for fixed lifetime perishable products. The targeted SC levels include production plants, distribution centers (DC), wholesalers, and retailers. The locations of the plants and retailers are predetermined, while the locations of DCs and wholesalers will be selected from potential locations. The elaborated model seeks to minimize the total cost and product transportation time in the SC and minimize expected demand deviation as well. The Normal Boundary Intersection (NBI) method is employed for solving the model, and GAMS software is used to determine the optimal values of decision variables.
Results
This study utilizes a case study of an Iranian broad dairy company that produces eleven product groups. Data for the study were collected from historical company records and expert interviews. According to the opinions of the experts, three different operational scenarios have been extracted, and the data related to each scenario, especially the customer demand, has been estimated according to historical data as well as the corrective opinions of the managers. The results of the proposed mathematical programming model showed that changes in demand did not have unexpected effects on the values of the objective function and did not change the general trend of the answer to the problem. On the other hand, changes in the percentage of perishability of the product had far less impact on the values of the objective functions as well as the membership function. The overall result is normal, and as a result, in general, these changes represent the stability of the model against the fluctuations of important parameters. A comparison of optimal results and reality reveals that the examined SC needs a redesign of its DCs and wholesalers' locations, and hybrid transportation methods should be used.
Conclusion
Supply chain design (SCD) of fixed lifetime perishable products at the strategic and tactical levels is indeed an important issue. By considering the research gap, this study developed a multi-objective and multi-level model for SCD of fixed lifetime perishable products, and new concepts such as varying perishability rates in storage and transportation facilities are considered. On the other hand, with regard to environmental uncertainty, important parameters such as demand and capacity of facilities are considered as probable parameters. Adding environmental and social factors as new objectives, hybrid transportation methods, and horizontal interactions in the same SC levels can be considered for model development. In order to solve the proposed model, NBI has been used, which has significant advantages compared to other solution methods. By turning the answer of the optimization model into a kind of decision-making problem, this technique gives flexibility to the decision-maker to choose the best solution for their supply chain design according to the weight of each goal. Also, the decision-maker can redesign and increase the adaptability of the supply chain by changing the important parameters of the problem over time.
Shima Salehi; Mohammad Taghi Taghavifard; Ghanbar Abbaspour esfeden; a alirezaee
Abstract
The integration of supply chain decisions aims to reduce costs and delivery time for customers. However, uncertainty in supply chain parameters, particularly demand, can disrupt this integration. The increased interest in probabilistic planning and simulation models in supply chain modeling is a response ...
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The integration of supply chain decisions aims to reduce costs and delivery time for customers. However, uncertainty in supply chain parameters, particularly demand, can disrupt this integration. The increased interest in probabilistic planning and simulation models in supply chain modeling is a response to this demand uncertainty. Therefore, the main objective of this study was to develop a multi-level, multi-product, multi-period supply chain network model that considers conflicting objectives such as cost minimization, delivery time minimization, and system-wide reliability maximization. The supply chain network under investigation consisted of four levels or subsystems: suppliers, manufacturers, distributors, and retailers. In this study, it was assumed that demand follows a random probabilistic distribution function. Consequently, simulation techniques were employed to estimate costs, including shipping costs, lost sales costs, and other expenses. After developing the multi-objective model, various scenarios were created based on different perspectives of inventory levels, namely minimum inventory, maximum inventory, and average inventory level. For each scenario, objective-related values were estimated. Ultimately, based on the Pareto optimal solutions obtained for each case of the model, the Vickor decision-making method was used to rank the answers and select the best solution from the proposed model. The results indicated that the second scenario, considering the average inventory level, was identified as the optimal solution for the described model.IntroductionToday, supply chain management (SCM) encompasses the entire production planning process for the supply chain, from raw material suppliers to the final customer. This has become a focal point for numerous researchers. In most supply chain designs, the objective has been to transfer products from one layer to another in order to meet strategic, tactical, and operational demands while minimizing complications arising from interrelationships and uncertainties across the chain. These challenges have posed significant decision-making hurdles in the supply chain domain. Supply chains can be regarded as complex systems wherein various factors interact with each other, resulting in emergent properties. Designing a versatile supply chain to address conflicting and diverse objectives requires considering them simultaneously and striking a balance among different criteria. The dynamic and intricate nature of the supply chain introduces a high level of uncertainty, thereby impacting the decision-making process in supply chain planning and influencing overall network performance. Based on the aforementioned issues, the focus of investigation includes the following: The examined supply chain network comprises four levels or subsystems, namely suppliers, manufacturers, distributors, and retailers. Raw materials are sourced from suppliers and sent to production factories, where each product is manufactured using a specific combination of raw materials. The products are then transported from manufacturers to distribution centers, and subsequently forwarded to retailers. The market is divided into different regions, and customer demands are fulfilled through visits to the retailers. Demand is assumed to be random and follows a probability distribution pattern. Consequently, simulation techniques are employed to estimate costs, including transportation costs, lost sales costs, and other expenses. Scenarios are created based on different perspectives at each level, focusing on inventory levels (minimum, maximum, and average). For each scenario, the values associated with the investigated objectives are estimated.Materials and methods In this research, data collection involved the examination of relevant literature, including articles published in international journals, books, and treatises. Documentary studies were conducted to gather information. To analyze the collected data, simulation and multi-objective programming concepts and methods were employed. Minitab and ED software were utilized for statistical analysis and simulation purposes.ConclusionsConsidering that the model can be solved under different conditions, including the current situation and various scenarios, the answers obtained for each state are Pareto optimal. This means that it is not possible to determine a single best answer for each state of the model. Therefore, before comparing the scenarios with each other, the Pareto optimal answers for each scenario should be ranked to identify the best options. In this research, a model for designing the supply chain network was presented, taking into account demand randomness. To better understand the proposed model and demonstrate its practicality, numerical examples were examined and evaluated using different scenarios and the Lingo software. It is important to note that the developed model in this study is independent of the number of facilities at each level of the supply chain and the parameter values. Therefore, the general form of this model can be applied to any production environment that aligns with the patterns presented in this research. The proposed model initially employed the design of experiments to estimate the mathematical relationship related to the cost objective function. After developing the multi-objective model, the Lingo software was used to solve the sample problem and evaluate the results under different scenarios. Finally, based on the Victor decision-making method, the Pareto optimal solutions for each state of the model were used to rank the answers and determine the best mode for the proposed models. Based on the obtained results, the third option or the second scenario is suggested as the preferred choice for the described model, considering the index values associated with each option
production and operations management
abolfazl Kazazi; Mohammad Taghi Taghavifard; reza kianimavi; mohsen hooshangi
Abstract
Companies, as one of the most prominent features of today's societies, are rapidly changing and evolving, and in the current situation, improving the innovation capabilities is one of the main goals of any living and active organization. The purpose of this study is to investigate the effect of social ...
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Companies, as one of the most prominent features of today's societies, are rapidly changing and evolving, and in the current situation, improving the innovation capabilities is one of the main goals of any living and active organization. The purpose of this study is to investigate the effect of social capital on innovation capabilities in supplier-buyer relationships by of opportunistic and intellectual property risks. The statistical sample in this study contains 95 of supply chain managers which are active in the escalator and elevator industry. The collected data were analyzed by using partial least squares method and Smart PLS software. The findings illustrate positive and significant effect of social capital on innovation capabilities (and indirectly through intellectual property risk). Opportunistic and intellectual property risks also have a significant negative impact on innovation capabilities. The results of this study for managers reveal the fact that investing in social capital in a buyer-supplier relationship not only does not hurt but also achieves a competitive advantage through innovation capabilities.
Hêriş Golpîra; Erfan Babaee Tirkolaee; Mohammad Taghi Taghavifard; Fayegh Zaheri
Abstract
Although the construction industry, especially because of its relationship with other economic sectors, is one of the most important sectors that plays a key role in a country's economic growth, the construction supply chain has been considered less attention. Therefore, construction supply chain network ...
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Although the construction industry, especially because of its relationship with other economic sectors, is one of the most important sectors that plays a key role in a country's economic growth, the construction supply chain has been considered less attention. Therefore, construction supply chain network design is of great importance for not only the companies but also governments. Thus, presenting an original mixed integer linear programming model, this paper introduces an optimal framework for a multi-project multi-resource multi-supplier construction supply chain network design for large construction companies with a decentralized procurement strategy. The main objective is to design a reliable supply chain model based on the quality of projects under the certain predefined budget, considering the entire supply chain as a single entity. Using a bi-objective approach to formulate the chain and the Lp-metric approach to solve the problem, make it possible to obtain a single-objective structural framework to reliability-quality trade-off consideration. To solve the problem in small and medium scales, GAMS software is employed, and a hybrid algorithm based on Genetic Algorithm (GA) and Simulated Annealing (SA) algorithm is developed to solve the large-scaled problem. The results show the capability of the model to attain optimal size of the chain as well as the quality-reliability trade-off considering a pre-specified budget. And, to the best of authors knowledge this is the first to obtain such a structured integrated framework in the construction supply chain.
Amir Khorrami; Mohammad Taghi Taghavifard; Seyed Mohammad Ali Khatami Firouzabadi
Abstract
Credit risk assessment is one of the key issues for banks and financial institutions and various models have been developed for this. This study uses Case Based reasoning (CBR) Model and considers a database of bank credit customers to assess the credit risk of bank applicants. For this, 9 criteria were ...
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Credit risk assessment is one of the key issues for banks and financial institutions and various models have been developed for this. This study uses Case Based reasoning (CBR) Model and considers a database of bank credit customers to assess the credit risk of bank applicants. For this, 9 criteria were selected based on the experts' opinion and were weighted using the Fuzzy Analytical Hierarchy Process (FAHP). Return check, housing situation and income level are the most important criteria for credit risk assessment of the bank applicants. Then, using the TOPSIS Technique, we could evaluates the similarity of the new item with actual past cases or evaluate the new applicant with the ideal option, and uses a case-based reasoning model to predict the likelihood of default or non-default applicants. Survey research was applied for this study and the research community was the records of previous bank applicants between 1390-94 years. This research is an applied and descriptive and descriptive study. The results show that the accuracy of the CBR model is higher than other validation and ranking methods of bank customers. The use of the CBR model in order to authenticate customers has obtained results far better than the performance of the credit sector experts, which led to the judgment of default or non-default of customers, indicating the high performance of the model used in comparison to the model used by bank and validation experts. CBR leads to the design an expert, specialized and intelligent system which addition to storing data in a database, stores models and templates for use.
Mohamad Taghi Taghavifard; Faezeh Abdoli Masinan
Abstract
The present research has done in Iran Insurance Company (Tehran Branch) in the year of 2016. The aim of this research is to study the effect of organizational social network features (Individual factors including: knowledge self-efficacy, enjoyment of helping and social factors include: social interaction ...
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The present research has done in Iran Insurance Company (Tehran Branch) in the year of 2016. The aim of this research is to study the effect of organizational social network features (Individual factors including: knowledge self-efficacy, enjoyment of helping and social factors include: social interaction ties, norm of reciprocity) on knowledge sharing activities and job performance. This applied research method is descriptive and survey. Literature review and field study have been used to collect information. The statistical population of this study included 230 employees (mainly experts) of Iran Insurance Company staff in Tehran. A group of 143 employees was selected as the sample for research through Cochran’s formula. Data was gathered by questionnaires and regression analysis was performed using SPSS and LISREL software to examine the hypotheses and Variables in quantitative method have been reviewed and evaluated by using structural equation and also confirmatory factor analysis. The results show that knowledge self-efficacy, enjoyment of helping, social interaction ties and norm of reciprocity have a positive effect on knowledge sharing activities which affect a person's job performance. Also, organizational social networks enable individuals to gather and share their work knowledge.
Abstract
This article benefits from the perspective of knowledge management on the organization social networks. This study was an attempt to investigate how employees benefit from organizational social networks in order to create value and expand the knowledge management. It also considers different usage of ...
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This article benefits from the perspective of knowledge management on the organization social networks. This study was an attempt to investigate how employees benefit from organizational social networks in order to create value and expand the knowledge management. It also considers different usage of organizational social networks and its value for knowledge management. Also, five functions of social networks have been studied, which includes: problem solving, generating ideas, updates, task management, and informal conversations. This research is an applied one and data was gathered by questionnaires and regression analysis with SPSS software was used as means of data analysis. The community of this study included 100 employees of " Hamkaran System", who use professional social networks. A group of 75 employees was selected as the sample group for research through Cochran's formula. To evaluate the Content validity and reliability of the questionnaire was used of Comments professors and experts and Cronbach's alpha. Results showed that the organizational social network is able to create value for innovation by helping people in effective use of social networking functions and enrich the abilities of knowledge. Effective participation in organizational social networks can cause to active knowledge management and create value. The purpose of valuation is assessment of the benefits of organizational social network to gain effective knowledge.
Samira Parsaiyan; Maghsoud Amiri; Parham Azimi; Mohammad Taghi Taghavifard
Abstract
The increasing concern about the deteriorating effects of supply chains related activities on the environment has led to the growing attention to develop green closed-loop supply chains in order to minimize greenhouse gases emission. This paper presents a green closed-loop supply chain model developed ...
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The increasing concern about the deteriorating effects of supply chains related activities on the environment has led to the growing attention to develop green closed-loop supply chains in order to minimize greenhouse gases emission. This paper presents a green closed-loop supply chain model developed under the demand uncertainty aiming at minimizing total cost and total CO2 emission across the supply chain, and maximizing the product’s market share in the presence of a competitor. In this regards, an agent-based market model is developed to estimate the demand’s parameter function then a hybrid simulation model which integrates agent-based and discrete event simulation modelling approaches is designed to simulate the closed-loop supply chain which is the novelty of this paper. Then, scenarios are created using Taguchi design of experiments (DOE) method, and are executed with the market model and the supply chain model to capture total cost, total CO2 and market share. A decision matrix is configured using scenarios and recorded results for three mentioned criteria and ELECTRE and SAW methods are used to rank scenarios and select the best one. The other contribution of this research is its comprehensiveness in considering variables related to three categories of inventory replenishment policy, marketing mix (price and advertisement) and transportation. An automotive industry case is provided to demonstrate the capabilities of the model and its applicability and effectiveness in resolving real-world problems.
Kaveh Khalili Damghani; Mohammad TaghaviFard; Kiaras Karbaschi
Abstract
The main goal of this paper is to evaluate the relative efficiency of each level of customer services in MELLI bank branches. A three stage process is defined as consecutive results of service provision to the customers. This process consists of sub-process such as customer expectations, customer satisfaction, ...
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The main goal of this paper is to evaluate the relative efficiency of each level of customer services in MELLI bank branches. A three stage process is defined as consecutive results of service provision to the customers. This process consists of sub-process such as customer expectations, customer satisfaction, and customer loyalty. A hybrid method based on Multi-criteria Satisfaction Analysis (MUSA) and network Data Envelopment Analysis (DEA) is proposed to evaluate the relative efficiency of 30 branches. In this way, first the customer satisfaction was measured through a direct questionnaire based on customers perceptions analysis and quantified using MUSA method. Then, the customer satisfaction scores and the other important evaluating criteria such as number of employees, average evaluation scores of staff, operating costs, the amount of deposits, total credit facilities, the number of new checking accounts, expectations and customer loyalty were considered in DEA model as inputs and outputs. A three-stage DEA model was used to evaluate the efficiency of bank branches. The proposed DEA model was based on multipliers perspective, output-oriented with constant return to scale. The proposed three-stage DEA model quantified and assessed the efficiency of customer expectations, customer satisfactions, and customer loyalties in branches. The results showed that the mean relative efficiency of selected branches in three sub-processes namely customer satisfaction, operational results and customer loyalty were 83%, 94%, and 90%, respectively. The mean efficiency of the overall process is 89%.And four branches (about 13% of sample) were placed on efficient frontier for all sub-processes. Based on research findings, the branches which have been efficient in customer expectations were also efficient in other sub-processes and the main process.
Mohammad Taghi Taghavifard; Ahmad Nadali
Volume 9, Issue 25 , July 2012, , Pages 85-107
Abstract
This research study aims at using Data Mining and Fuzzy Logicapproaches to classify the credit scoring of banking system applicantsas to cover uncertainties and ambiguity connected with applicantclasses and also variables that affect their behavior.The methodology, according to a standard Data Mining ...
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This research study aims at using Data Mining and Fuzzy Logicapproaches to classify the credit scoring of banking system applicantsas to cover uncertainties and ambiguity connected with applicantclasses and also variables that affect their behavior.The methodology, according to a standard Data Mining process, is tocollect and refine the client data, then those variables which are inlinguistic forms are converted to fuzzy variables under the supervisionof banking experts and final data are modeled using Fuzzy DecisionTree, subsequently. The unfuzzy data are also modeled using the otheralgorithms.The results of the study suggest that as far as client distinctionaccuracy is concerned Fuzzy Decision Tree produces better resultscompared to Traditional Trees, Neural Networks, and statisticalprocedures such as Logistic Regression and Bayesian Network.However, it is not as accurate as Support Vector Machine and GeneticTree. On the other hand, Fuzzy Decision Tree technique has gainedbetter prediction than prediction performance of bank credit scoringexperts.
Mohammad Taghi Taghavifard; Amir Mahdi Malek
Volume 9, Issue 22 , September 2011, , Pages 135-165
Abstract
Key Performance Indicators, help an organization to define and measure the progress of organization toward organizational goals. Key Planned Performance Indicators (KPPI) are the tools for measure the progress of organization toward goals and strategic. Since the Decision Makers are concerned with these ...
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Key Performance Indicators, help an organization to define and measure the progress of organization toward organizational goals. Key Planned Performance Indicators (KPPI) are the tools for measure the progress of organization toward goals and strategic. Since the Decision Makers are concerned with these attributes and indices in uncertain environments, selection of these indices is a Multiple-Attribute Decision-Making problem. In the past, several methods such as the linear weighting methods, AHP, TOPSIS, Fuzzy Logic and Mathematical programming have been used to solve the indices selection problem. In this thesis, we give a new grey-based approach to deal with the indices selection problem with regards to organizational strategic plans. Firstly, the weights and ratings of strategic- base attributes for all alternatives are described by linguistic variables that can be expressed in grey numbers. Secondly, using a Grey Possibility Degree (GPD), the ranking order of all alternatives is determined. Finally, an example of indices selection for instruction and research department of IRIB is used to illustrate the proposed approach.
Mohammad Reza Taghva; Mehrdad Kazeruni; Mohammad Taghi Taghavifard; Mohammad Rahmani
Volume 4, Issue 12 , March 2006, , Pages 183-211
Abstract
One of the important aspects of ERP both for practitioners and researchers are the “implementing considerations”. While companies worldwide have spent considerable investments on the ERP systems, but they've confronted unexpected problems and realization of its final benefits is blurred. ...
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One of the important aspects of ERP both for practitioners and researchers are the “implementing considerations”. While companies worldwide have spent considerable investments on the ERP systems, but they've confronted unexpected problems and realization of its final benefits is blurred. In order to implement ERP with minimum risk and assured ROI, it’s necessary' to identify the organizational parameters affecting it positively or negatively. This study aims at describing proper organizational conditions for this organizational system, for Iranian manufacturing industries, and Irankhodro Company as a case. This organizational condition has been investigated in an organizational Architecture framework. OA has been viewed from a plan/design view and the research model has been developed as a variable called design coherence and its effect on the ERP success. Design coherence, is the coherence between HR attitudes about the dimensions of the organization and the real design. The results show that in the proper OA for ERP there exists design coherence. This finding is verified through existing evidences obtained from past studies. Regarding the case company, Irankhodro we can say that the aforementioned organization should move toward this coherence in order to preparation for ERP. Managing the system reliability regarding the organizational information systems (EISs) is an important consideration which merit attention for maximizing the benefits of investigation on such an expensive information system called ERP.
Mohammad Taghi Taghavifard; Isaq Saeidi Robat
Volume 3, Issue 9 , June 2005, , Pages 1-27
Abstract
This research paper has focused on the deployment of Information Technology (IT) in the health sector. The main goal is to determine the key factors for the implementation ...
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This research paper has focused on the deployment of Information Technology (IT) in the health sector. The main goal is to determine the key factors for the implementation of IT in a service establishment (i.e. Imam Khomeini Hospital Emergency Room). In this regard, Donabedian Methodology is used for the ranking of the factors and Eriksson-Penker Method was utilized for the modeling of the existing as well as the ideal processes. For the purpose of integration between modeling processes and software deployment, a service-oriented architecture has been applied. For the purpose of data and information collection to answer the research questions, questionnaires were distributed and collected and interviews were performed. Four basic questions to be answered are as follows:
1- What are the stumbling blocks for the conversion of existing processes (processes which are directly or indirectly affected by IT) to the ideal ones toward the implementation of IT? (More specifically in Imam Khorneini Hospital Emergency Room).
2- What are the solutions for removing the identified problems in the current processes of a sector (say emergency room)?
3- How can IT affect on the performance of the emergency room?
4- How are the outcome indicators for the deployment of IT In the emergency room classified and utilized?
At the end, for the purpose of validation and verification, the proposed node I was implemented. The result obtained indicates that the proposed nodel is quite valid and proper.
