فهرست مطالب سید احمدرضا شاهنگیان

Paying attention to the conservation of water resources in order to prevent water crises is one of the most important duties of people in the community, including officials. In this regard, the most effective action is water demand management, for which there are different methods. One of these methods is pressure management in order to demand management, which can be used in normal operating conditions as well as in the event of water scarcity. On the other hand, in critical situations where the available water does not meet the total demand, policies such as intermittent water supply are adopted, which are associated with many problems. Therefore, an alternative method is needed to minimize the disadvantages of intermittent water supply,to meet the objectives of demand management and, at the same time is feasible, efficient, and economical. In this research, a combined simulation and optimization model is created by using EPANET2.2 and MATLAB software. With this model, the effects of adopting a water demand management approach using pressure management on the hydraulics of water distribution networks will be investigated. In this research, optimization is done in two approaches. In each case, a different objective function is defined and a genetic algorithm is used for optimization. The developed model has been analyzed on the WDN of Baharestan city located in Isfahan province. The results show that the model is able to reduce the average network pressure by 8 meters by finding the optimal location and adjusting pressure for pressure-reducing valves under normal conditions. Also, during water scarcity, it is able to distribute the available water among the demand nodes considering equity and justice principles. After imposing an 8% deficit on the network, without applying for a pressure management program, 8 demand nodes experienced a shortage between 15 and 30% and 19 experienced a deficit below 5%. However, after optimizing the pressure, only 3 demand nodes experienced a shortage between 15 and 25% and 6 nodes experienced a shortage of less than 5%.

Encouraging households to adopt residential water conservation behaviors, as an efficient strategy for sustainable water supply, has caught the attention of water demand management. However, the success of such policies depends on the voluntary acceptance of these measures by urban households. Considering the important role of psychology in explaining human behavior, the present research explored the key socio-psychological factors underlying the household adoption of WCBs and how these behaviors can be explained by expanding the theory of planned behavior via adding the habit variable to the TPB’s main model. In the current study, which focuses solely on water curtailment behaviors (behavioral conservation), 343 Isfahan citizens participated. In this regard, a cross-sectional survey was conducted using a structured questionnaire, as a research instrument, and the structural equation modeling method was also applied for data analysis. The results revealed that, by adding the habit variable to the TPB's main model, the extended model can predict 75% and 51% in the variance of intention to adopt water curtailment behaviors and water curtailment behaviors, respectively. Based on the findings, the attitude and perceived behavioral control variables had a significant positive relationship with intention, whereby attitude had the most predictive power of intention to adopt water curtailment behaviors. Moreover, the habit and intention variables were significantly and positively related to water curtailment behaviors, of which habit was the most important determinant of behavior. However, subjective norm had no significant relationship with intention, and perceived behavioral control was not significantly related to behavior. Finally, policymakers are advised to develop and implement awareness-raising and education campaigns aimed at (1) creating positive attitude toward WCBs among urban households, (2) increasing their self-efficacy and self-confidence in performing these actions, and (3) improving and/or changing their water conservation habits in order to improve WCBs among urban households.

As the population and urbanization increase, policymakers consider urban water management more often; however, these policies can positively and negatively affect the urban water system. In recent years, following the increase in the water crisis in Isfahan province, pressure management has been applied to reduce access to water as a new water demand management policy in different cities of this province. The present study investigates the environmental effects of such policy in the new city of Baharestan (Isfahan province) during the 2018-2036 period, using a life cycle approach and different percentages of available water shortages. SimaPro software is used to conduct the life cycle assessment for processes such as network failure and energy consumption at the pumping station. The life cycle assessment is performed based on the conditions of the study area. The results show that significant part of the environmental effects in the water supply and distribution network is caused by network failures, which, compared to energy consumption, have many effects on most midpoint and endpoint environmental effects. So that the endpoint environmental effects of network failures are, on average, 2.2 times greater than that of pumping systems. The water distribution network and pumping system can minimize their environmental impact by implementing a pressure management policy. With pressure management, the endpoint environmental effects in both short-term and long-term scenarios are reduced by 14.7% and 20.2%, respectively.

Water demand management policies (WDMPs) are being proposed as a solution to water scarcity. Applying any of WDMPs can have far-reaching consequences even on the urban infrastructures like wastewater systems. However, studies on the effects of WDMPs often focused on the water sector, and there is a research gap in the wastewater section. Therefore, in this study, the impact of the application of WDMPs on sewage systems from a social point of view has been evaluated during different scenarios of demand reduction. For this purpose, the Social Life Cycle Assessment (SLCA) method, which is a subset of life cycle thinking, has been used. In this regard, Baharestan city (located in Isfahan province) is selected. The groups (stakeholders) affected by the social effects of WDMPs on wastewater systems have been identified and their characteristics have been determined. Stakeholders are social and local community, workers and consumers. Then, by compiling a questionnaire and using the opinion of experts in this field, the Analytic Hierarchy Process (AHP) method has been used for scoring. Then, taking into account the intensity of the effects of each indicator in each scenario, the social score of all scenarios is obtained. The results show that social and local community has the biggest weight than other stakeholders (wight of 0.45), and safe and healthy living condition is the most important indicator of it. Also, the scenario that has the least decline in water consumption and sewage production is socially better than others.

Ecological and social science researchers have long faced the challenge of modeling the intrinsic complexity of socio-ecological systems. A popular approach to understand and investigate these systems is agent-based modeling, which has been used not only in ecological sciences but in many other disciplines over the years and has become a widely used tool nowadays. Despite the importance of this modeling approach, there was no standard protocol to make and present these models by 2006. Hence, several expert modelers who covered a wide range of areas in ecology suggested the ODD protocol (Overview, design concepts, and details) as a standard for describing individual-based models (e.g., agent-based models) in 2006. After that, some providers of the first version of the ODD protocol have developed an updated version of this protocol in 2010 to resolve problems and ambiguities of the original version, as an alternative for the previous version, by reviewing research that used this protocol. Then, considering the fundamental role of human decisions in agent-based modeling, a new version of this protocol named ODD+D was introduced in 2013, specifically for this modeling approach. The purpose of the ODD+D protocol was the development and modification of the ODD protocol to create a standard for describing agent-based models so that it can consider human decision-making within itself. Due to the importance of applying this protocol in the structure of agent-based modeling studies, the present research introduces the ODD protocol, reviews its evolution over recent years, and addresses the detailed description of different versions.

In recent years due to water resources scarcity and increase in water extraction costs, more attention has been given to water consumption; specifically, urban water consumption as a more sensitive and high priority demand with high costs of supplying. Accordingly the water and wastewater authorities are directed to modern water management methods including water demand management policies and water conservation. These practices and policies not only have widespread positive and negative effects in different aspects, but also by affecting the different components of the system, can make more severe and immense effects. Amongst the most important aspects related to such policies are the social aspect and the main stakeholders of the urban water management, i.e. households. Thus, the purpose of this paper is to address these different aspects by reviewing the requirements and obligations of the integrated framework in assessment of water demand management policies. To this end, firstly the importance and necessity of assessing the water demand management policies has been discussed. Then, different approaches for integrated environmental assessment and management have been introduced by demonstrating the main implications. Also, some illustrative examples are presented. Finally, the agent-based model is introduces as the integrated approach for investigating the micro-level social interaction and assessment of macro-level aggregated impacts.

Ensuring water security in the face of population growth and resource scarcity has posed a serious challenge for policymakers in urban areas and led them to water demand management (WDM) approaches. Water conservation as a key factor in WDM is an effective solution to the sustainable urban water supply that includes two categories: water curtailment behaviors and water-efficiency behaviors. Given that the voluntary acceptance of water conservation behaviors by individuals, understanding the psychological determinant processes of these behaviors is an important aspect in designing effective policies and interventions in this area. Therefore, the purpose of this study was to investigate factors affecting water conservation intentions and behaviors among Tehran citizens using the theory of planned behavior (TPB). The data collected using both online and offline surveys (N=820) in Tehran by a structured questionnaire, which its validity was confirmed by experts, and its reliability was confirmed by Cronbach's alpha coefficient. Data analyze conducted through the structural equation modeling. Based on the results, the TPB can explain 83% and 40% of the variance in water curtailment intentions and behaviors, respectively, and 57% and 37% of the variance in water-efficiency intentions and behaviors, respectively. The results also suggested attitude and perceived behavioral control affect the intention regarding both behaviors, but subjective norm does not affect the intention for both behaviors. In addition, the results revealed that both behaviors influenced by intentions and perceived behavioral control. Finally, based on the results, implications for improving residential water conservation and suggestions for future research are provided.

Water demand management policies have widespread positive and negative effects on various aspects and can affect the severity and extent of these effects by affecting various components of system. Also, the application of these policies to social systems, which are composed of adaptable factors with complex behaviors (indirect effects) and interact with each other on micro-scale, causes emerging phenomena at system-level (macro-scale). In addition to the complicates of inner nature of socio-ecological systems and urban water supply-demand cycle, the complicates of urban infrastructure behaviors also present another challenge in this area. Therefore, urban water system is known as a complex adaptive system that requires integrated evaluation and modeling of system complexities in different dimensions. So, this article reviews the two main concepts regarding evaluation and modeling of environmental policies, including urban water management policies, namely (1)modeling of complex adaptive systems and (2)integrated evaluation and modeling and the types of common approaches of them. By reviewing these concepts and previous researches in the field of urban water management, the interactive cycle and modeling process in this field is extracted. This paper begins with an introduction to the importance of urban water management, especially demand management, and continues with an overview of the basic requirements and concepts in the structure of assessment and modeling of environmental policies. The proposed framework is then presented based on past researches. At the end, agent-based modeling as a powerful tool in evaluation and modeling of urban water management has been investigated using the two approaches above.

Few studies are made about the effect of environmental conditions on the leakage flow rate. Some of these researches show that environmental conditions play an important role in leakage flow rate. On the contrary, there are other researches opposing this idea. The purpose of this research is to investigate evidence of the effect of environmental conditions on leakage flow rate. Based on this idea, some tests were carried out in the college of engineering at the university of Tehran, using a circular experimental set up at high pressure discharging to the atmosphere. Various ranges of pressure up to 50 m of water were imposed on a 110 mm diameter aged steel pipe with some holes on the pipe surface. In the next step, by using the experimental results, an analytical model in ANSYS software was developed and outputs were compared with experimental data. Later a proper mathematical turbulent model was derived. Furthermore, the effect of submerged conditions was investigated by this appropriate numerical model. The results of this research showed that static pressure fluctuations in submerged jet had significant effect on discharge and the rate of leakage was reduced in comparison with atmospheric discharge. According to the results, pressure reduction in 5 m head pressure could affect the leakage discharge under submerged condition up to 55 percent when compared with the case of discharging to the atmosphere. With pressures above 20 m, smaller changes were observed. These changes were limited to less than 10 percent. The aforementioned reduction depended on the imposed head of water at leakage point and pressure value inside the pipe. Finally, a relationship between leakage outflow and internal pressure of pipe was proposed.