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      • Open Access Article

        1 - Assessing the Remedy Policies of “Urmia Lake” Basin Crises By A System Dynamics Approach
        علیرضا  لاری جابر  مهرکار mir saman pishvaee
        The Urmia Lake is the greatest lake in Iran and the second saline lake in the world. This ecosystem contains a wide numbers of animals and plants. Urmia Lake has placed in the northwest of Iran and has economical, social and environmental importance for local people. Un More
        The Urmia Lake is the greatest lake in Iran and the second saline lake in the world. This ecosystem contains a wide numbers of animals and plants. Urmia Lake has placed in the northwest of Iran and has economical, social and environmental importance for local people. Unfortunately, in recent years, various and complex problems have decreased the level of water in Urmia Lake strongly and deteriorate the future life of this lake significantly. However, in the last decade, more than half of the lake area has changed to the salt plains. Many researches address the Urmia Lake crises in recent years; however, most of them are unable to model the dynamism of Urmia basin as a whole system in long-term period. In this paper, the critical factors affecting the reduction of Urmia Lake water level are defined. In addition, a system dynamics model, which is able to illustrate the behavior of the whole system of Urmia Lake, is proposed. The developed model is validated through comparison analysis and the derived results show the high accuracy (around 97%) of the proposed model. Three policies are proposed and evaluated to increase the water inflow and Lake level. The simulation results show that the hybrid policy has more efficiency than the other ones. Also, a prediction of Urmia Lake volume is proposed based on model till 1405. Manuscript profile
      • Open Access Article

        2 - Innovation in combining theory of constraints thinking process with system dynamics (A case study : supply chain management )
        mehdi ghazanfari حسين  محمدي
        Theory of Constraints is a kind of management philosophy that uses a systemic approach for understanding and analyzing the whole system. With this attitude identifying and removing the limitations (contradiction or problem that can limit the output of the system) in a s More
        Theory of Constraints is a kind of management philosophy that uses a systemic approach for understanding and analyzing the whole system. With this attitude identifying and removing the limitations (contradiction or problem that can limit the output of the system) in a systematic process of change is possible. The tools that the theory of constraints uses for identifying, removing and transferring from current adverse conditions to future desirable conditions, is called the thinking process tools. But always there is this need that the effect of various factors on each other in the process is investigated as a feedback loop and in long term. Thus the system dynamics methodology can be used as a complementary tool to this. In fact, This paper aims to describe show to integrate theory of constraints and system dynamics according to their assumptions and their philosophical foundation. To explain how to use these two intersect methods, the problem of inventory management in SCM, which today is known of the challenges, is used. The results show that the combination of these two approaches in terms of theoretical foundation, offer good supplement to understand the problem . Manuscript profile
      • Open Access Article

        3 - The Analysis of Implementing the Objectification of Subsidy Plan on Drug Supply Chain: A System Dynamics Approach
        محدثه  کلانتری زهرا  حیاتی هانی  شاهمرادی مقدم mir saman pishvaee
        Objectification of subsidy plan could be described as one of the best government plans and policies. According to perspective document 2025 that consider the first place in economy for Iran and regarding to government financial limitation on national economy, the reform More
        Objectification of subsidy plan could be described as one of the best government plans and policies. According to perspective document 2025 that consider the first place in economy for Iran and regarding to government financial limitation on national economy, the reform of economic policies is a part of economic necessity for Iran. In this paper, by establishing a suitable system dynamics model, we plan to represent the efficacy of the direct subsidy distribution on level satisfaction of people from drug price changes and also consider the efficacy of this subsidy distribution on total profit of drug supply chain. First, a system dynamics of drug supply chain by considering the direct subsidy distribution have modeled. Then, the model is simulated. To do this, the casual loop diagram is depicted and then with its help, the stock and flow diagram constructed. The simulation results show the unsuitable performance for implementing the subsidy objectification. As a result, two strategies have been suggested to improve the situation. Manuscript profile
      • Open Access Article

        4 - Modeling of Foresight for Sustainable Development Using Scenario Planning and System dynamics Approach (case study: Yazd Province)
        حمید بابایی میبدی Gholamreza  Godarzi Adel Azar Firozeh  Azizi
        Nowadays, the wide changes in various dimensions put managers in serious challenges. This issues cause the current plans will no longer be able to response, therefore it is necessary to use new approaches such as foresighting. Meanwhile, one of the main concerns of mana More
        Nowadays, the wide changes in various dimensions put managers in serious challenges. This issues cause the current plans will no longer be able to response, therefore it is necessary to use new approaches such as foresighting. Meanwhile, one of the main concerns of managers is the effect of their decisions on the key variables. This study using a foresight and systematic approaches and design the dynamic sustainable development model to seeks an answer to this important management issue. First we presented a framework for sustainable development and then, using the “Mic Mac” method identified the key drivers of sustainable development. In the next step, by designing a scenario portfolio, future possible scenarios for sustainable development were determined. Finally, by designing a regional sustainable development model, it is possible to simulate scenarios and decisions, and determine the appropriate scenarios from the possible multi-dimensional scenarios Manuscript profile
      • Open Access Article

        5 - Extension of The development methodology for hybrid multi-scale AB-SD simulation modeling in learning organizations
            Alinaghi Mashayekhi
        Performing the concurrent analysis of organizational, departmental and individual scales alongside macro and micro levels of abstraction in temporal, spatial and event-driven contexts may significantly clarify the concept of learning, and develops the opportunities for More
        Performing the concurrent analysis of organizational, departmental and individual scales alongside macro and micro levels of abstraction in temporal, spatial and event-driven contexts may significantly clarify the concept of learning, and develops the opportunities for effective policy making accordingly. It would also help to improve the performance indicators of the system and its involved agents globally. Due to Ignorance of aforementioned concurrent analysis, the relationship between organizational learning and learning in lower scales has been ambiguous, and monitoring the effect of organizational learning on organization performance indicators has been neglected. Hence, whether organizational learning is an effective factor in the amplitude of organization competitive advantages or not has remained a serious question yet. However, a potential solution to this question has got conceivable through the multi-method system modeling perspective. Design and analysis of integrated multi-scale learning in organizations are now possible through hybrid modeling and simulation and the extended methodology presented in this research along with the related architecture. The outcome is a plain platform which embraces lucid modeling of complex abstract concepts including learning in organizations comprehensively. Future case studies may be required to further confirm the applicability of this methodology and underpin its administrative value. Manuscript profile
      • Open Access Article

        6 - A dynamic model of the impact of information and communication technology on GDP growth
        mohammad taghi taghavi fard melika mehrkam Esfandiar Jahangard Ameneh  Khadivar
        ICT plays an important role in accelerating economic growth, especially in today's age of the Internet and mobile telecommunications. Due to the upward trend in the use of information and communication technology in the countries of the world, this part of the economy d More
        ICT plays an important role in accelerating economic growth, especially in today's age of the Internet and mobile telecommunications. Due to the upward trend in the use of information and communication technology in the countries of the world, this part of the economy demands a lot of attention. Improved policies due to the impact of information and communication technology on the economy are one of the top programs of governments in developed and developing countries.A review of the literature shows that few systematic studies have examined the role of information and communication technology in GDP growth and the impact of various variables on the role of information and communication technology has not been sufficiently studied.The present study uses systematic approach and system dynamics methodology and examine interactions of ICT variables including ICT access, ICT development, ICT usage etc. with macroeconomic variables such as GDP, total factor productivity, ICT Capital examines ICT's value-added share of GDP and so on and presents a conceptual model of the role of ICT in GDP growth. The qualitative model designed in this study can be the basis for future quantitative research and mathematical simulation with a systematic approach to information and communication technology and GDP. Manuscript profile
      • Open Access Article

        7 - Designing a Model for Assessing Effective Factors in the Excellence of Human Resources with the Approach of System Dynamics(Case study: Yazd Province Ceramic tile Industry)
        amirehsan eshaghiyeh firuzabadi hossein eslami hadi hematian
        Abstract Background: In the ceramic tile industry, like other industries and companies, in order to increase competition in the market, they need capable human resources to comply with the requirements and principles of professional ethics. Based on this, the purpose o More
        Abstract Background: In the ceramic tile industry, like other industries and companies, in order to increase competition in the market, they need capable human resources to comply with the requirements and principles of professional ethics. Based on this, the purpose of this study was to design a model to evaluate the effective factors in the excellence of human resources in order to develop professional ethics in the tile and ceramic industry of Yazd province. Method: This research is applied in terms of purpose and analytical-descriptive in terms of data collection from the survey branch. First, the initial and proposed model was drawn based on the research background and literature. The statistical population in the present study includes three groups of experts and specialists, information and data and personnel of the ceramic tile industry in Yazd province.At first, a panel of experts (15-20) people were selected and dynamic and key variables affecting the model were identified through semi-structured interviews.While collecting statistical data and financial information, a questionnaire was prepared using the opinion of experts and measured using factor analysis, and then distributed among the personnel of the ceramic tile industry (about 22,000 people).Using Morgan table, 373 people were selected as a sample. Then, according to the data collected using powerful Wesim software, the model was simulated in three stages and then validated. Results: The results of nonlinear mathematical model, which was analyzed by computer simulation using Vensim software, show: Factors affecting the excellence of human resources are factors inside and outside the organization, and accordingly, scenarios were described in order to promote the variables affecting the excellence of human resources and with the aim of developing professional ethics. Conclusion: The simulation results show that managers can increase the ability of employees, futures research, attention to exports and reduce the influence of the supervisor by presenting policies such as Employment control, strong and modern marketing, and the policy of eliminating growth patterns and the perspective of developing professional ethics achieve this important goal. Also, attracting managers with ethical leadership styles and having appropriate educational and research experiences and increasing the excellence of human resources based on the development of principles of professional ethics in the industry leads to Increase commitment and loyalty to the system, service motivation and ultimately improve the performance of ceramic tile personnel. Manuscript profile
      • Open Access Article

        8 - Designing an evaluation model of the effective factors on customers’ satisfaction with a system dynamics approach in the ceramic tile industry of Yazd province
        amir ehsan Ishaqiyeh Firouzabadi
        Abstract IntroductionTherefore, the purpose of this study is to present a simulated model of factors affecting customer satisfaction based on dynamic methodology in order to analyze the factors and also improve customer satisfaction. Method:This research is applied More
        Abstract IntroductionTherefore, the purpose of this study is to present a simulated model of factors affecting customer satisfaction based on dynamic methodology in order to analyze the factors and also improve customer satisfaction. Method:This research is applied in terms of purpose and analytical-descriptive in terms of data collection from the survey branch. First, the initial and proposed model was drawn based on the research background and literature. The statistical population in the present study includes three groups of experts and specialists, information and data and personnel of the ceramic tile industry in Yazd province. At first, a panel of experts (15-20) people were selected and dynamic and key variables affecting the model were identified through semi-structured interviews.While collecting statistical data and financial information, a questionnaire was prepared using the opinion of experts and measured using factor analysis. Results: through simulation by Vensim, show that factors that increase customer satisfaction include quality, product diversity, and on-time delivery and factors that decrease customer satisfaction include ceramic tile import from other countries, low quality, high price, and lack of on-time delivery. Conclusion: Therefore, companies' attention to the model presented in this study can have a significant effect on increasing customer satisfaction. Managers can also play an effective role in increasing customer satisfaction by adopting strategic and creative policies. Manuscript profile
      • Open Access Article

        9 - Evaluation of Policies for the Timely Implementation of Iran's Government Infrastructure Construction Projects Using System Dynamics (SD) Approach
        Mehrdad HajiEsmaili Ali mohammad Ahmadvand Marzieh  Samadi-Foroushani
        Objective: One of the major challenges in the management of construction projects is the lack of understanding of the mechanisms that cause delays in construction. In the meantime, government infrastructure construction projects have a more complex situation, so that th More
        Objective: One of the major challenges in the management of construction projects is the lack of understanding of the mechanisms that cause delays in construction. In the meantime, government infrastructure construction projects have a more complex situation, so that the success in the timely implementation of a construction project within the framework of government laws is one of the biggest goals and concerns of managers and agents involved in these types of projects. Methodology: It can be the present study identifies the mechanisms of project time delay risks based on system dynamics in order to identify and evaluate policies for the timely implementation of construction projects. For this purpose, first the literature and background were examined and during the semi-structured interview with the participants of the research, the effective factors on the timely implementation of the Iranian government construction project were identified. In the continuation of the dynamic model of the timely implementation of the Anrani project, the simulation was carried out using the data of the infrastructure operation project of the first section of Mobarakeh railway, Sefidasht, Shahrekord. Conclusion: After validation; According to the results of the sensitivity analysis of the system dynamics model, the exploitation policies during the construction project were identified in three strategies of providing project financial resources, project planning and control, and accountability of the project beneficiaries. In the following, it was also designed and applied to the model with selected combined policies. comparing the behavior of key model The combined selected policy Manuscript profile