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This study aims to solve the operational disruptions caused by some nancial problems of supply chain members. Supply chain coordination is extensively used to enhance the performance and pro tability of the supply chain members and the whole system. Coordination can be achieved by some techniques that persuade the members of a decentralized supply chain to participate in the supply chain optimization plan. Financial problems such as lack of liquidity, high cost of debt, limited nancing capacity, and so on, can negatively impact the operational activities of a rm. In the context of the supply chain, these disruptive eects can spread throughout the supply chain and cause ineciency for other members as well as the involved rm. So, supply chain coordination mechanisms can also be in uenced by these nancial constraints. However, few studies are analyzing the ability of classical supply chain coordination mechanisms to coordinate the supply chain in the presence of capital shortage and nancing costs. The goal of this paper is to propose an ecient coordinating scheme based on the trade credit nancing contract for a multiproduct supply chain consisting of a capital-constrained manufacturer who faces nancing limitations and multiple suppliers. The member's interactions are modeled as a Stackelberg game in the form of a bi-level optimization problem in which the suppliers as leaders form a coalition at the upper level and the manufacturer acts as a follower at the lower level. Two scenarios are considered concerning the contract terms. In the rst scenario, the manufacturer is obliged to pay the suppliers until a certain time before the end of the period. But, in the second scenario, it can extend the repayments to suppliers until the end of the period. The proposed model in both scenarios is solved by two population-based metaheuristics, Genetic Algorithm, and dierential evolution. The results indicate that the trade credit contract in the rst scenario is not able to coordinate the supply chain but if the manufacturer is allowed to postpone its payments until the end of the period, the proposed contract fully coordinates the supply chain.

Due to the large volume of exports and imports of goods, developing the country's ports as the country's communication gateways is a need. A comparative economic study of dierent countries shows that sustainable development in these countries is always been accompanied by investment. This fantastic economic phenomenon has reached signi cant proportions in the world today. This paper aims to present a model for investing in the container terminal of ports with a system dynamics approach and examine various management policies. The proposed model considered these subsystems: growth and investment, capacity, berth, and access channels. According to the proposed model variables, investment data in the container terminal of Shahid Rajaei port for ten years from 1388 to 1397 is entered into the model, and simulation results are presented. The variables that are evaluated are investment per unit of container, entry tari of ships to port, container storage tari, the tari of transport operators in the container terminal, and depth of berth and access channel. In order to con rm the proposed model, rst, the model is approved by the software, and then some important validation tests are used, and the validity of the proposed model is con rmed. Also, to examine the sensitivity of performance variables to changes in policy parameters, policies adopted in the three areas of service quality, revenue, and the capacity of incoming ships to the port, which are: increase of investment per container unit, reduction of port service tari and increase of berth depth, were implemented on the model in the period of 1397-1406. Finally, the selected policies in each area are implemented simultaneously. The results of the simultaneous implementation of the proposed policies are satisfactory. There is a 24% increase in the operating capacity of the container terminal, a 31% increase in equipment capacity, a 30% increase in revenue, and a 96% increase in the capacity of incoming ships. As a result, by adopting the proposed policy of this research, the performance of the container terminal of Shahid Rajaei port can improve.

Today, the method of Build, operation and Transfer of accepted and effective methods for investing in the construction of fast infrastructure projects required by countries. However, several risks may affect the Build, operation, and Transfer contracts.One of the most significant topics in study of BOT is process of its allocation to public and private sections. In this paper, by presenting the position of the risk-sharing process in the formation of Build, operation, and Transfer projects, a guidance framework is developed for how to allocate risk among the project's agents.Therefore, before starting a project and contracting, each of the project risks must be determined according to the appropriate criteria. Study continues by studying risk’s allocation in two quantitative and qualitative levels. Qualitative model uses Bayesian model to allocate risk for employer and contractor in 93.56% and 98.31% levels of significance. In order to identify the risks in the high way project of Tehran-Rasht, we first used 30 action questionnaires and then qualitative assigning and sharing the risk. In quantitative model, game theory used to allocate minimum of total cost while 35% of risk assigned to employer and 65% to contractor.

Supply chain coordination is extensively used as an effective tool for firms to stay competitive and improve their profitability. However, this solution may fail if the financial problems of the firms are ignored in the operations. To solve this challenge, we have proposed a coordination scheme using internal financing for a three-level supply chain facing some financial constraints. This case is modeled as a bi-objective optimization problem that optimizes both system’s costs and service level. We have solved the model using εconstraint method. The results show that the proposed coordination scheme can provide full service level (100%) to the customer, while the noncoordinated system cannot reach more than 50% of the service level. Furthermore, the system’s operational and financial costs are reduced by coordination.

In this article, which was conducted based on a case study in Iran's New Energy Organization (SANA), an attempt was made to develop sustainable development management strategies and consider the involvement of many positive and negative factors in choosing a wind turbine for a wind farm in the country. Use appropriate MADM methods. In this regard, after calculating the important factors in the evaluation of a wind turbine technology according to the principles of sustainable development management, AHP was used to weight the criteria and sub-criteria and TOPSIS was used to select the best option. In order to obtain the AHP hierarchy, the descriptive-field method was used, and the desired data was collected in line with the design of the model and different levels of the AHP tree, and the weighting process was carried out based on this. Several interviews were conducted to achieve criteria and sub-criteria. Also, a researcher-made questionnaire in this field was prepared and distributed among the people involved in the wind turbine industry, and finally, the agreed criteria and sub-criteria were calculated. Based on the conducted field studies, effective criteria in sustainable development management by choosing the right wind turbine for a wind farm in five general areas including: "Technical specifications and coordinates", "Technology manufacturer (provider) specifications", "Opportunity fields", "Generators" "Cost" and "Risks and Risk Factors" as well as 31 sub-criteria were identified and categorized. Based on the results, Sinovel Wind International Company was introduced as the best option.

One of the most important issues in many project-oriented organizations is the risk management of the ongoing projects of that organization. In this regard, in the first step, the potential risks of projects should be identified under a systematic and comprehensive scheme, and then, using appropriate and desirable methods, they should be evaluated in terms of their probability and their impact on project goals. In this study, considering Bakhtar Petrochemical Company, a holding company, as one of the largest companies that construct and operate petrochemical projects in Iran as a case study, the current and potential uncertainties and risks of petrochemical projects in Iran have been identified and evaluated. Two methods, namely documentation review and interview, have been used to identify risks. This procedure has led to the identification and classification of 104 potential risks in petrochemical projects in two categories and eight sub-categories. Also, since the risk assessment is an evidential, intuitive, and empirical decision-making process, the Evidential Reasoning approach has been used for this stage. Evidential Reasoning, based on the Multi-Attribute Decision-Making approach and Dempster-Shafer's Theory of Evidence, is a useful and effective method to deal with overly intuitive and inaccurate judgments made in this uncertain environment. Using this method, in addition to assessing and ranking the identified risks, has also produced a measurement of the level of recognition of the identified risks.

Raw materials supply costs form more than 60 percent of the price of a product in an organization. Therefore, the raw material supply planning has considerable effect in reducing the cost. Supplier management is one of the most important parts in supply chain management. Most of firms have been spending considerable amount of their revenues on purchasing. Hence supplier selection is one of the most important functions of purchasing management. The aim of this research is providing a linear integer mathematical model for supplier selection and order allocation with shortage and solving the model with three dimensional Fordyce–Webster Algorithm. In this research for the first time, maximum once period backorder cost is added to the three dimensional Fordyce–Webster Algorithm. In order to measuring performance of the proposed model, a high-voltage switches company's data and data from two other examples have been applied to the proposed model and the model has been studied in terms of " changing the ratio of holding cost and backorder cost" and " number of suppliers and number of time period". Finally, to solve the model, maximum once period backorder cost is added to the three dimensional Fordyce–Webster Algorithm.

Evaluation of the quality of urban transportation services is vital to improve productivity, profitability and customer satisfaction. All of the transportation organizations evaluate various parameters related to the quality of transportation services, such as performance, reliability, security, and convenience, on a regular basis. This evaluation can be done by customers, service personnel and transportation experts. Since the assessment of the quality of the metro lines has not been carried out in Iran by fuzzy MCDM method, in this paper, we present a hybrid approach for evaluating the service quality of metro lines in Tehran based on SERVQUAL and fuzzy TOPSIS. Our proposed approach consists of two steps. The first one involves development of a SERVQUAL based questionnaire to collect data for measuring transportation service quality and in the second step; fuzzy TOPSIS method is used to select the best alternative. Fuzzy TOPSIS generates an overall performance score for each alternative. The alternative with the highest score is finally chosen. The final ranking results show that the red metro line is the best of four metro lines in terms of service quality, followed by green line, yellow line and blue line.

Water scarcity is now one of the most critical challenges in most countries around the world, especially in Iran. One of the key ways to control and manage this issue is the investigation of the water demand. Qom city has always been encountered with a threat due to its location in the dry area of the country and in the absence of proper management in the near future, there will be serious dangers in this field. The purpose of this thesis is investigation of water demand dynamics from method of system dynamics in Qom city. Dynamic of various variables such as population, water demand, surface water resources, ground water, water supply in this model has been used by Vensim software. The maximum relative difference (%) of this model for estimation of water demand was found to be 7%. The change of birth rate from 4% to 2% resulted in 29% reduction of water demand level in 1405 compared with current trend. . Base on this result, the policy of population control had the most important effect on water demand. The price effect on water demand is negligible, so that, 20% increase of price leaded to 2.04% reduction in level of water demand in 1405 compared with current trend.

Determining a unique goal in Goal Programming (GP) method for each objective function due to restriction of information is dicult and inecient. To overcome this problem, a type of goal programing methods called multiple-choice goal programing has been developed, in which multiple levels introduced for each objective. In this paper, the goals are considered as alternatives, which decision-makers express their agreement or disagreement with them through interval-valued intuitive fuzzy numbers (IVIFNs). In the complex multi-attribute largegroup decision making problems where attribute values are interval-valued intuitionistic fuzzy numbers, the number of decision attributes is often large and their correlation degrees are high, which increase the diffb01culty of decision making and thus infb02uence the accuracy of the result. To integrate multiple opinion with a high degree of correlation and choosing a goal, a principal component analysis algorithm for interval-valued intuitive fuzzy numbers (IVIF-PCA) is applied. IVIF-PCA model represents major information of original attributes, effectively reduces the dimensions of attribute spaces, and synthesizes original attributes into several relatively independent comprehensive variables. The proposed approach has enabled to consider the opinions of decision makers with dierent interests in large groups and the degree of their Doubt in the model, also it can reduce the computational complexity through selecting a limited number of goals through a scienti c and accurate method based on IVIF-PCA Algorithm. To evaluate the performance of the proposed mechanism, a numerical example is presented and solved. Previous approaches, in addition to their inability for considering the decision makers' doubt degree in goal de nition, require to identify several variables to take into account the aspirations set by a large group of decision makers, which increase the computational complexity. In contrast, the proposed approach in addition to considering the decision makers' doubt degree in goal de nition, reduce the computational complexity through IVIF- PCA Algorithm.

The results of dynamic efficiency evaluation not only help managers to realize their business' position in competitive market, but also enable them to compare current company’s performance with previous periods and do strategic planning properly. For doing so, network data envelopment analysis is a logical approach. Hence, the main objective of this illustration is to measure dynamic efficiency by means of network data envelopment analysis technique. Although different approaches in network DEA are introduced recently, the need for a comprehensive methodology in this area is remained because of the defects of previous methodologies. Consequently, a novel approach based on multi-objective optimization is introduced in this paper in order to measure the efficiency of a network structure. Finally, the case of Machine Made Carpet Industry (MMCI) is used and the dynamic performance of MMCI's companies in the period of four years is measured. Efficiency results of case data showed that the methodology proposed in this paper is able to eliminate defects of previous approaches and evaluate both total and annual efficiency simultaneously

Kanban control systems used to optimize inventory levels just in time (JIT) production systems. Evaluation of kanban systems are based on flow control principles and it plays a very important role in production systems. This article presents a new dynamic card control methodology in order to keep a high level of performance measures. The main advantage of the proposed method is easy to adjust parameters. A simulation model for generalized kanban control system with dynamic adjustment of kanban size is proposed. Simulation experiments designed to test the effect of kanban sizes on performance measures such as total production time and amount of work in process, as well. The results of the simulation model indicate the improvement in production rate and reduction of backlog demand by automatic and dynamic adjustment of kanban size.

Minimization of costs and maximization of product quality are key factors for success in a supply chain network (SCN).The SCN is considered four echelons: suppliers, middle assemblers, final assembler and retailers that supply a single type product consists of four components. In this paper in addition to the supplier selection, the assemblers and warehouses are selected. The assembly process of the products such as automobile, tractor, consist of multiple stage, therefore in this paper, the assemblers are divided in two groups: multiple middle assemblers (which assemble the component of the product), a final assembler (assembles the final product). In this paper an integrated approach for middle assemblers selection based on multi attribute decision making (MADM) and suppliers selection based on multi objective decision making (MODM) is proposed. First the weight of the attributes (cost, quality, delivered time and warranty) is determined by ENTROPY method and then the middle assemblers are selected by TOPSIS method. The model consists of two minimization of costs and maximization of quality which is solved by CHEBYSHEV goal programming to select suppliers. Application of proposed method is shown by numerical example and optimal solutions have been compared considering one objective and two objectives.

Scheduling plays an important role in project management. However, in addition to providing suitable scheduling, constraints during project implementation should also be noted. This paper proposes bi-objective resource-constrained project scheduling model with the objectives of minimizing project completion time, as well as minimizing the leveling cost of the used resources, in accordance with the employer demands and the contractor developed. To better study this model performance, a real case study related to the topic, were selected. Since the proposed research problem has been proven to be NP-hard as well as large-scale case study, after analyzing the landscape, genetic algorithm to solve problem were offered. Finally, the results of solving real-world algorithms were compared with the results. Results show that the model and algorithm can be used in other similar projects as well.

In today's competitive environment, performance evaluation plays an important role in developing better strategic plans and improving efficiency of any organization. Due to the importance of insurance industry in socioeconomic growth and development of societies, it is notable to take into account the fact that the improvement in efficiency and effectiveness of the industry relies on the efficiency of the inner active insurance companies, this is one of the major necessities of any country. In addition, over the last decade, Iran insurance industry has implemented significant changes including the involvement of private sector in this industry and departure from government domination. These developments also clarify the necessity and importance of using appropriate methods to assess the effectiveness of different organizational levels. The purpose of this study is to design a comprehensive framework to combine the balanced scorecard (BSC) and data envelopment analysis (DEA) approaches for evaluating performance of insurance companies. The advantages of the proposed model are its weighted evaluation and maintenance of the balance among BSC perspectives, providing a holistic view and flexibility in involving factors and its outstanding power in detecting the efficient and inefficient units. In this study, first by studying the documents and interviewing with experts in insurance industry, the most important performance indexes in four areas were determined based on BSC method, i.e., financial, customer, internal processes, and learning and growth. Subsequently, by applying the DEA technique, the efficiency of a sample of 18 private Iranian insurance companies was measured. The results of the proposed model indicate that the performance of the aforementioned companies is quite satisfactory through BSC perspective. Also, in the performed aggregated ranking, the companies, i.e., Parsian, Arman, and Sina, obtained the highest scores, respectively. Ultimately, using the generated performance scores (in each area of BSC), after determining the reference groups, the optimal solutions for improving the efficiency of the inefficient companies were determined.

With entering container into transportation area, this area has experienced a huge change. However, the imbalance problem between the input and output containers exists in ports until now. This imbalance between import and export of goods has created a problem called Empty Container. In this paper, due to the theoretical and practical issue challenges in the problem, the reposition of empty containers under certain and uncertain conditions of some problem parameters is investigated. At first, a new model of two-objective planning of reposition of empty containers under certain conditions was presented for the first time in the literature. Thereafter, in order to reduce the effects of uncertain parameter fluctuation under various scenarios in the real world, a combinational approach of robust optimization and risk management is used. The reposition of empty containers robust model is presented by considering uncertainty of several problem parameters like demand and supply as well as loading and unloading capacity under three different scenarios which those probable scenarios are determined using risk management method. In order to evaluate and validate the both presented models, the data from Iran maritime port network are used. The computational results indicate the appropriate performance of proposed deterministic model, efficiency of proposed robust model under uncertainty conditions, and also the importance of using robust optimization approach in creating reposition of empty containers robust plans under uncertain conditions.

Road crashes are one of main death causes in Iran. Therefore, studying accident records and roads’ safety problems are of significant importance. Human, environment and vehicles are three principal factors that may affect each crash individually or with others. The road factor is solvable by identifying and eliminating road troubles on time. The main goal in road safety audit is to solve environment and road problems. The detected points do not contribute to accidents and casualties equally. Thus, the points; risk level should be ranked in order to efficiently provide suggestions. A step-by-step method is introduced for road sections’ safety prioritization using 6 parameters of number of accidents, road side conditions, traffic signs, road markings, pavement status, and access point density. It’s the first time that five safety audit and accident factors are used in such models. Steps include field inspection, crash statistics analysis, expert interview, entropy, and TOPSIS. The case study is chosen as Sanandaj-Kamyaran road (Primary two-lane road) in Kordestan province due to its high traffic, importance and high number of accidents. The results reveal that the segments which are rich in accidental history and, also, suffer from important safety audit factors such as high intersection density and poor pavement quality, are of the highest risk.

In this paper, a new algorithm based on the framework of the imperialist competitive algorithm for solving resource constrained project scheduling problem (RCPSP) will be proposed. In this problem, the activities are scheduled based on the resource and precedence relationships constraints in a way that the makes pan will be minimized. In order to model the assimilation process, a uniform crossover has been used, and to avoid premature convergence of the proposed algorithm, two revolution operators including one point revolution and multi-point revolution will be introduced. Also, in order to enhance the exploitation ability, a combined local search including permutation based local search (PBLS) and forward-backward improvement (FBI) is performed. The algorithm parameters are determined by designing Taguchi experiment, and the efficiency of proposed ICA is demonstrated by solving PSPLIB problems. Computational results and comparisons with some existing algorithms show that the proposed algorithm can produce near-optimal solution for small problems and competitive solution for large ones.

With entering container into transportation area, this area experienced a huge change; however, the imbalance problem between input and output container in ports has been standing until now. This imbalance between import and export has made a problem called Empty Container, as the import and export ports are facing surplus and shortage of empty container. In this paper, to solve the desired problem, the empty containers transportation planning model with two goals, minimizing total costs including transportation, storage, shortage, loading and unloading cost of empty containers, and maximizing availability of empty container formulated by minimizing sum of the maximum shortage of empty containers at the export ports in all periods, has been developed. Then the proposed model was linearized, and with using weighting method was converted to a single objective of the minimizing costs. Finally, to verify the proposed model, a numerical example by considering a time-space network of Iranian maritime ports has been solved applying the Lp-metrics method, using GAMs software. The computational results indicates the efficiency of the proposed model in making the problem balance, reducing the total cost with 66% compared to the real world, and optimality of set targets.

Avalanches are of highly probable natural disasters on mountain roads during cold seasons. This natural phenomenon is also a usual reason of road closures and casualties in Iran especially in roads between Tehran and northern cities and western and north-western roads. In order to preventing or reducing avalanche incidents, first, more risky points should be identified and next, suitable safety actions must be considered. Previous studies mainly use regional and geological data based on field inspections, whereas, several other parameters are considered in this study and a combined model is developed. The parameters are snow depth, side slope, vegetation, avalanche frequency, vehicle collision possibility, daily traffic count, and expert interview. Ten avalanche-prone points are identified in Karaj-Chalous road and are prioritized using method of TOPSIS. The results show that avalanche frequency is the most effective factor. Moreover, the results show that sections of 62퍍63퍍, 63퍍68퍍, and 70퍍74퍍 are the most risky ones and safety solutions should be considered in these points.