Queuing theory in a very simple Definition is a branch of mathematics for analysis and management of waiting lines. It is developed in the first years of twentieth century when telephone waiting Lines were studied. Servers are not necessarily human beings but in queuing systems that human Agents are servers, it is possible to consider the queuing system as a dynamic system. This is because in these systems, elements of system are interactive and they are interacting with each other. In this paper DYNAMICS of a queuing system are presented by a Dynamic model using System DYNAMICS Approach. Afterwards, DYNAMICS of a simple Queuing system is studied by investigating impacts of some elements on other ones.

There exists a strong need to explore simulation techniques that not only represent complex dynamic system in a realistic way but also allow the involvement of end users in model development to increase their confidence in the MODELING process. System DYNAMICS, a feedback-based object-oriented simulation approach, is presented for mode ling reservior operations. The increased speed of model development, the trust developed in the model due to user participation, the possibility of group model development, and the effective communication of model results are main strengths of this approach. The ease of model modification in response to changes in the system and the ability to perform sensitivity analysis make this approach more attractive compared with systems analysis techniques for MODELING reservior operations.In this paper, system DYNAMICS is used to simulate a hydropower reservoir operation. The developed model is applied to the Tang-e-Mashoure reservoir in upstream of Karkhe in Iran.

System DYNAMICS, a feedback - based object - oriented simulation approach, not only represents complex dynamic systemic systems in a realistic way but also allows the involvement of end users in model development to increase their confidence in MODELING process. The increased speed of model development, the possibility of group model development, the effective communication of model results, and the trust developed in the model due to user participation are the main strengths of this approach. The ease of model modification in response to changes in the system and the ability to perform sensitivity analysis make this approach more attractive compared with systems analysis techniques for MODELING water management systems. In this study, a system DYNAMICS model was developed for the Zayandehrud basin in central Iran. This model contains river basin, dam reservoir, plains, irrigation systems, and groundwater. Current operation rule is conjunctive use of ground and surface water. Allocation factor for each irrigation system is computed based on the feedback from groundwater storage in its zone. Deficit water is extracted from groundwater. The results show that applying better rules can not only satisfy all demands such as Gaw khuni swamp environmental demand, but it can also prevent groundwater level drawdown in future.

Several theories have been presented about the corporate capital structure,some researchers believe that the structure of capital and firm value depend on each other. Moreover, others believe that the firm value is not influenced by any changes in the structure of capital, and with the change in the structure of capital, the value of the firm remains constant. The present research studies the historical theories of capital structure and presents the classification of existing theories in terms of the optimal capital structure. This classification is subdivided into two categories: the presence of an optimal capital structure and the absence of an optimal capital structure. With the historical review of theories of capital structure and the presence of an optimal capital structure or the lack of an optimal capital structure, it seems that none has been a complete model and so far, no one has been able to provide an optimal capital structure. In this research, from the system DYNAMICS approach and using VENSIM software, the capital structure and share price of the company have been studied and the results of model simulation with real data are to ensure the correct performance of the model behavior. And the results show that financing through debt in the capital structure of the company has a significant effect on the debt cost rate and capital cost rate and does not have a significant effect on stock prices. Finally, the share price shows little sensitivity to the company's financial structure.

Adaptive cruise control (ACC) and stop-and-go scenarios are example of problems related with longitudinal control. Driver assistant systems currently under development by the most automotive manufactories around the world. This Research describes a vehicle speed & vehicle-to-vehicle distance control algorithm for vehicle cruise control and also vehicle stop-and-go cruise control. So first, a complete dynamic model of car has been simulated that consists of an SI engine, automatic transmission and tire. The vehicle longitudinal control scheme consists of a speed control algorithm and a distance control algorithm and throttle-brake control law. A desired acceleration for the vehicle has been designed using linear quadratic optimal control theory. It has been shown that the two proposed control laws provide good performance.

This paper presents an effective approach for kinematic and dynamic MODELING of high mobility Wheeled Mobile Robots (WMR). As an example of these robots. the method has been applied to the CEDRA rescue robot, which is a complex, multibody mechanism. The model is derived for 6-DOF motions, enabling movements in x, g and z directions, as well as for roll, pitch and yaw rotations. Forward kinematics equations are derived using the Denavit-Hartenberg method and Jacobian matrices for the wheels. Moreover, the inverse kinematics of the robot are obtained and solved for the wheel velocities and steering commands. in terms of the desired velocity, heading and measured link angles. Finally, the DYNAMICS of the rover mechanism have been thoroughly studied and analyzed. Due to the complexity of this multi-body system, especially on rough terrain, Kane's method of DYNAMICS has been used to model this problem. The proposed approach and method can easily be extended to other mechanisms and rovers.

This study aims to design a model to realize real estate income tax in Tabriz city with due attention to the tax collection process. According to the related literature, the variables of "tax payment, " "real estate, " "tax evasion, " "investment incentive, " "rent and real estate speculation, " and "advertisement in tax collection" are considered as key variables, affecting the conceptual model of real estate tax system. According to the dynamic systems method, the interaction and relationships between variables are shown by state-flow diagrams based on the literature and experts' opinions. These relationships are finally simulated by Vensim software. The results show that advertisement has a significant effect on the amount of taxes paid by taxpayers. Tax transparency has also reduced rents for taxpayers and ultimately reduced tax evasion and timely tax collection in the estimated budget of real estate resources and single-occupancy jobs. Scenarios show that lowering the tax rate in the trading and business market and large corporations and businesses' rental income are strongly influenced by tax revenues.