Introduction Climate change is the greatest threat to humanity, because it is the main factor in increasing the frequency and severity of atmospheric events such as droughts, floods, heat waves, etc. that are experienced today. Climate change can cause a wide range of environmental problems, including severe drought and water scarcity, crop loss, and increased socioeconomic consequences. One way to identify climate change is to evaluate climate and temperature indicators. Based on statistical tests and time series of occurrence of these parameters in the long run, the status of change and its trend can be identified. Given the importance of the impact of climate change on all sectors, the study of the consequences of these changes requires the study of all sectors and effective factors with a systemic approach. One of the concerns of human society is the changes that have caused climate change due to global warming. In this regard, given the importance of climate change on all sectors, the study of the consequences of these changes requires the study of all sectors and factors with a systemic approach. Considering the importance of climate change and its effects, this study seeks to answer the following questions by considering important climatic parameters and vulnerable urban dimensions (economic, social, political, environmental): 1-The trend of climate change changes (Temperature and rainfall, humidity, wind speed) what is it like in Ahvaz? 2-What is the causal relationship between the causes of climate change and vulnerable sectors in the city of Ahvaz? 3-What are the effects and consequences of climate change on the city of Ahvaz? Materials & Methods The research methodology is based on statistical tests and qualitative modeling with a systemic approach. The present study analyzes the trend of changes in climatic parameters including temperature, precipitation, relative humidity, and wind speed for a period of 30 years (1991-2020) in Ahvaz using the statistical Mann-Kendall Test was examined. Then, using the science of system dynamics, the causal relationships between variables and structural modeling of the consequences of climate change in Vensim software are investigated. The main stage of using the system dynamics approach is to try to understand and identify the feedback loops of the system under study, for which purpose diagrams of causal loops are drawn. In this study, inputs are the factors that shape climate change are factors that affect the city system. System outputs will be the consequences of climate change. Results & Discussion Based on the results of the analysis of the trend of climatic parameters, the city of Ahvaz in the study period has faced an increase in temperature, increase in relative humidity, decrease in wind speed, and decrease in rainfall. During the 30-year trend (1991-2020), the average rainfall has been (226) mm, each year (1. 32) mm, has decreased and followed a downward trend. The average temperature has been (25. 38) degrees Celsius, it has increased every year (by 0. 051) degrees, which shows an increasing trend over 30 years. Based on the results, the average relative humidity was (41. 1), which increased every year (0. 007). Also, according to the results, the average wind speed is (2. 65 m/s) and has decreased by about (0. 018) every year. Therefore, the wind speed shows a decreasing trend over 30 years. Given that climate change refers to the spatial-temporal changes in the long-term average of climatic elements, the results of this study clearly showed that climatic parameters (temperature, relative humidity, precipitation, wind speed) in the study area have undergone fundamental changes. The consequences of climate change on all economic, social, political, and environmental aspects were evaluated. The results of qualitative modeling and causal relationship showed that climate change in Ahwaz has a direct impact on different sectors of water resources, agricultural production, and energy consumption. Variables of (reduction of water reserves upstream, extreme heat waves) are the most important leverage points of the model. Different outcomes have complex interactions with each other in such a way that they affect different economic, social, environmental, and political dimensions and ultimately intensify each other's effects on reducing the quality of life and increasing climate migration. Conclusion As a result, climate change has consequences such as increasing unemployment, reducing the quality of life, reducing urban resilience, and ultimately increasing climate migration in the city of Ahvaz, and the urban environment is not equipped to adapt to climate change.

A common method for controlling a group of parallel converters in decentralized control strategy structure in an island microgrid, the use is the droop-down characteristics of frequency ω-P and voltage E-Q. However, the problem with using this method is that the reactive power is not properly distributed (in proportion to the capacity of the micronutrients) between the micronutrients, which may lead to overload in the converters. Microgrids may also suffer from dynamic stability problems such as power fluctuations, which can be increased by switching between active and reactive power control. To avoid this problem, the X / R ratio of transmission lines is an important parameter that should be carefully considered in the design of micronutrient controllers. By linearizing and simplifying conditions, the control system conversion function model becomes a single input-single output system, which is efficient enough to show the relationship between control parameters such as slope of droop characteristics and derivative sentences, virtual impedance, and voltage controllers. Using this model, stability conditions for different parameters are analyzed. Also, to improve power distribution stability, common droop strategies are modified by adjusting the slope as well as adding nonlinear sentence sections. This approach reduces the coupling between active and reactive power control and reduces the dependence of power distribution on grid parameters such as the X / R ratio. To evaluate the reliability of the proposed model, the simulation results in a sample island microgrid in MATLAB software are presented.

The progress and industrialization of human societies in the past century have intensified the concentration of greenhouse gases and led to climatic change of the different parts of the world. The sign of this climatic change is the long-lasting change in the meteorological parameters. Drought is a serious hydrological phenomenon that may happen due to not receiving rainfall in a vast region and in any climatic conditions. This phenomenon has considerable effects on the economy of environment and water sources. Thus, the study of the climatic impacts of drought can play an important role in the planning and management of water source systems, especially during a period of climatic drought. Paying attention to the climatic change and its effects on water sources is of great importance. Unfortunately, it is not studied sufficiently in our country. In this research, we aim to identify the effects of climatic changes on the time and place distribution pattern of drought using system dynamic approach. This approach is used to study several factors and dual relation of the climatic changes with the time and place trends of drought simultaneously.

Many dynamic processes are characterized by parametric or structural uncertainties due to internal and externaldisturbances. Existing deterministic models could not handle the uncertainties inherent in these processes. A valuablealternative to control these processes is the use of a type-3 fuzzy system. Since type-3 fuzzy systems use threedimensionalmembership functions, they have more capacity to model uncertainties. This paper introduces the designof a type-3 fuzzy logic system (FLS) for the control of dynamic plants. Utilizing type-3 fuzzy logic, the architectureof the type-3 fuzzy control system (T3FCS) is proposed. The knowledge base of the controller is constructed and itsdesign stages are presented. The inference mechanism of type-3 FLS is developed using α slices and interval type-3membership functions. The proposed type-3 FLS is utilized for controlling nonlinear dynamic plants. The modelingof the proposed T3FCS is performed and transient response characteristic is derived using different stepwise excitationsignals. A comparison of the designed system with the type-1 FLS-based system is provided. The obtained simulationresult demonstrates the efficiency of using the proposed type-3 FLS in the control of dynamic systems characterized byuncertainties.

Maybe an event can't be modeled completely through one game but there is more chance with several games. With emphasis on players' rationality, we present new properties of strategic games, which result in the production of other games. Here, a new attitude to modeling will be presented in game theory as a dynamic system of strategic games and its some applications such as analysis of the clash between the United States and Iran in Iraq will be provided. In this system with emphasis on players' rationality, the relationship between strategic games and explicitly the dynamics present in interactions among players will be examined. In addition, we introduce a new game called trickery game. This game shows a good reason for the cunning of some people in everyday life. Cooperation is a hallmark of human society. In many cases, our study provides a mechanism to move towards cooperation between players.

Due to the lack of measurements in many regions, wave characteristics are estimated using different methods. Wave climate hindcasting/forecasting is mostly conducted by numerical models or empirical methods. Until now, different empirical methods have been developed for wave hindcasting. However, with the development of high speed processors, several sophisticated numerical models have been developed for wave prediction. These models are mostly phase-averaged spectral wave models developed in three generations. In the last two decades, third generation wave models have been used widely in academic and practical projects. In this regard, Port and Maritime Organization has produced his own model, PMO Dynamic. This model has been developed as a part of first three phases of Monitoring and Modeling of Study of Iranian Coasts project. PMO Dynamic package is a software available for engineering purposes. It has several modules that have been developed for different objectives. Wave model is the module which is used for the generation and transformation of wind waves in coastal areas. In this paper, in order to test the PMO Dynamic model capabilities, it has been applied for the prediction of wave parameters in Bushehr Bay and the results have been compared with MIKE21 SW model and measured data.

This paper presents the different systems that used in suspension and generaly study the benefits and harmful effects of this systems. The first step in analysis of a system is presentation of a sutable physical model. The main aim of model is not necessary a complex model, but is a model that explain the relationsheeps between variabilities of system conditions really, and provide the aims of disigner. From these physical models can be used in analysis of stability, ride quality and stiffness coefficient of sprins, and damping coefficient, influency of road unevenness.