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The significant rainfall in October 2018 in northern Iran caused devastating flooding that caused considerable economic losses and claimed at least nine lives. Following the flooding, several bridges have suffered different levels of damage. Immediately after the event, the authors conducted a field investigation to study the performance of RC bridges during the flood. This paper presents the failure modes of flood-affected bridges and provides reasons for every failure case. The results revealed that scour around foundations, pier tilting, flexural failure of piers, and superstructure unseating were the most significant failure modes observed. Pile-supported bridges performed notably better than those with shallow foundations. In addition, observations have revealed that structural integrity plays a crucial role in the general stability of bridges during flooding. Pier ductility is another significant parameter that affects the performance of bridges during flood events. Finally, fragility curves were developed based on the empirical data set provided from the post-flood status of the bridges in the affected region. The river flow velocity (Vs), maximum flow discharge (Qp), and Qp normalized to the 10-year average river discharge (Qm) were considered intensity measures of the fragility analysis. The correlation analyses revealed that despite Vs and Qp/Qm , the flow discharge was not an appropriate intensity measure for generating fragility curves. [ABSTRACT FROM AUTHOR]

The development and expansion of 20th-century urbanization have led to large-scale populated regions that did not exist prior to this era. City-region is a kind of 20-century large-scale concept recognized as the most advanced stage of urban development. Regardless of its long history, the concept of city-region does not enjoy a standard definition. In this vein, the present paper seeks to provide a suitable framework for the primary argument determining the city-region boundary. Indeed, understanding the boundary allows planners to study a precise area, resulting in refining the concept and meticulously planning. Therefore, as applied research, it is aimed to respond to the practical problem in spatial planning by expanding and developing the city-region's knowledge base. The paper has a mixed-method, using content analysis, the Structural Equation Model techniques, and Hot spot analysis. The results introduce six factors for determining the city-region's boundary, including economic self-sufficiency, community relation, regional competitiveness, balanced management, services and infrastructure capacities, and the space of flows. The research's flexible model allows planners to adjust it based on their field of study, inferring that the proposed model is utterly comprehensive; however, having access to different databases, scholars may encounter a challenge to adapt indicators. Accordingly, indicators should be customized based on general ones. In this study, the indicators are customized according to Iran's data sources, and the output framework is tested on the Tehran region that deals with inefficiencies in urban and regional planning. [ABSTRACT FROM AUTHOR]

Population growth and building mechanical devices to achieve thermal comfort have increased energy consumption. The hot and humid climates account for high energy consumption in the building sector. Meanwhile, for centuries, vernacular houses in this climate complied with their environment. This paper examined the vernacular architectural elements of two southern cities of Iran with hot and humid climate conditions on the coast of Makran. However, a comprehensive study of these elements and their role in indoor air quality and the creation of thermal comfort has yet to be discovered. This study incorporated climatic information into a computational fluid dynamics simulation to analyze vernacular architectural elements in the study area. By combining the architectural elements of Bushehr and Chabahar vernacular houses, 13 building models were created, with a component of each element to be investigated. Results showed which elements boost the incoming flow and which models become more effective in developing an enhanced model in terms of ventilation. However, a wind exchanger (Dudkesh) works better than a wind catcher and Taremeh in terms of airflow velocity across the buildings. Additionally, models could establish about 38% comfortable hours during the year with natural ventilation and sun shading in Bushehr. Before HVAC systems and the emergence of technology, people in different cities discovered different ways of ventilating and cooling their homes. Among these strategies was the use of architectural elements in their vernacular dwellings. A tall wind catcher or a central courtyard could change the air condition and was not solely intended for aesthetic purposes. Many of Iran's ancient cities have architectural elements unique to their old vernacular architecture. According to their location, these elements differed in size and shape based on the climate. Chabahar and Bushehr are located near the Persian Gulf and Oman Sea in southern Iran. Although both are located in hot and humid areas, the architectural elements used in their vernacular architecture differ. In this study, we tried to examine their function individually or by combining them to see whether they could work if installed in another environment. [ABSTRACT FROM AUTHOR]

In recent years, mining pollution has become a serious worldwide public health concern. One major issue in this field is concerned with arsenic-contaminated sediment. This paper, therefore, intends to determine the extent to which enhanced electrokinetic (EK) remediation is effective for remedying a case study of arsenic-contaminated sediment. The first section of this paper is devoted to determining the best enhancement agent at various solution concentrations and better discovering soil–metal action and reaction by leaching experiments. The sediment was collected from the zinc processing plant cold filter cake (CFC) in Shams Abad Industrial City, Iran, with a 5,700 mg/kg concentration of arsenic. In the second section of the study, ethylenediaminetetraacetic acid, citric acid, and sodium hydroxide as electrolyte conditioning solutions and sodium hydroxide for pretreatment have been evaluated as enhancement techniques for the remediation of arsenic-contaminated sediment during the electrokinetic method in tests with a duration of 8 days. Also, increasing the voltage gradient from 1 to 1.5 V/cm was assessed as another enhancement technique for improving the electrokinetic removal efficiency of arsenic. Finally, the result of experiments showed no significant increase in arsenic removal efficiency in using pretreatment and increasing the applied voltage; however, interestingly, using citric acid 0.5 M as the catholyte solution enhanced the removal efficiency up to 33.51%. [ABSTRACT FROM AUTHOR]

Despite scattered attempts to frame the processes of population and economic decline in cities of the global South through urban shrinkage, mechanisms identified in the core studies of this concept do not easily translate into the local dynamics and expressions in these cities. This paper investigates the applicability of urban shrinkage as a conceptual tool for analyzing the intertwined processes of population and economic decline in small-size cities of the South. In doing so, we examine the multiscalar production of economic decline and population loss in Kermanshah province in Iran and the small-size city of Harsin in this province. Adopting qualitative and quantitative methods, we identify different economic and political processes at national, provincial, and county scales that play out in shaping variegated geography of population loss and gain in this province and then examine the variegated spatial patterns of population loss and gain in Harsin. The paper suggests that instead of an analytical tool, urban shrinkage can be seen more as an umbrella term for framing such dynamics, at least in small-size cities of the South. Nevertheless, the paper concludes by identifying the ways in which urban shrinkage studies can provide a fruitful contribution to such an analysis. [ABSTRACT FROM AUTHOR]

In recent decades, rapid urbanization has presented many social, economic, cultural, environmental, and physical challenges and threats in big cities. Sustainable small city development (SSCD) is a sustainable utilised way for reducing the rural–urban population from rural settlements to big cities. In this regard, this research looks to analyze the role of five dimensions—economic, cultural, social, environmental, and physical indicators—in the Golbaf city development in Kerman County, Kerman province, Iran. For this purpose, this paper presents a scientific sustainable model in small cities development using the size of the sample (374 residents). These 374 cases have been selected by the Cochran formula. The SPSS software package 23 has been used to analyze data (T regression test). This research uses the analytic hierarchy process model to prioritize factors affecting the development of Golbaf city. In addition, this research has used the Friedman test to evaluate the similarity of important factors. The results of the research indicate that the environmental indicator is in the first rank and the two indicators of culture and economy are in the next rank of factors affecting the development of Golbaf city. [ABSTRACT FROM AUTHOR]

Structural assessment and seismic vulnerability of ancient masonry buildings is a difficult task even when employing advanced specialized technical skills, which requires a complex study. This paper aims to assess the structural and seismic safety of the Esfahan Shah Mosque in Iran by numerically investigating the nonlinear behavior of the mosque for different scenarios and identifying if there is a correlation between crack patterns resulting from numerical analysis, inspection, and historical evidence. First, the numerical model of the mosque is developed and updated using the experimental parameters obtained from a nondestructive test (NDT) campaign that included ambient vibration and sonic testing. Second, the finite element calibrated model is used to evaluate the structural behavior of the mosque under vertical loading, including the influence of the soil and a sensitivity analysis varying the masonry material properties. Besides, the paper discusses the structural behavior of radial stiffening walls that connect the inner and outer domes of the mosque. Finally, pushover analysis was performed to assess the seismic safety of the building and the efficiency of the structural strengthening implemented in the early 20th century. The different technical observations and analyses lead to a better understanding of the double dome and the eyvan (a rectangular space, usually vaulted, walled on three sides, with one end entirely open) as the most vulnerable parts of the structure, which validates the structural strengthening of the 1930s. Yet, improving the connection between the stiffening walls and the two domes could effectively increase the global structural performance of the building. [ABSTRACT FROM AUTHOR]

Although good water governance (GWG) is a widely accepted concept, mistaking its principles for silver bullet approaches has hindered its successful applications. This highlights the idea that one-size-fits-all thinking does not satisfy the need to navigate toward sustainable outcomes in ever-changing complex water systems. This also indicates that endeavors toward governing water systems must be tailored to the specific context that these systems are nested within. Scholars have pointed out the importance of residents' input in contextualizing water governance practices. With that being said, this paper proposes an innovative approach to tailoring principles of GWG to the context by building an analytical framework upon which survey research was conducted. The survey, it took input from three categories of residents, namely experts, authorities, and experienced locals. Analyzing the data led to a group decision-making problem that was approached using fuzzy risk-based multiple-attribute decision-making methods, including technique for order of preference by similarity to ideal solution and ordered weighted averaging, while considering the amount of consensus among mentioned groups. Furthermore, to validate the results of the decision-making problem analysis, additional interviews were conducted to get a more pragmatic picture of the situation. Sistan Delta in Iran was selected as a case study mainly due to the current undesirable situation and also the international social, political, and environmental significance of the area. This study aims to take the first step of rethinking water governance in the area. The results indicated that to operationalize good governance, the principles of collaboration, legitimacy, adaptability, and trust and engagement must be prior considerations to redefine the water governance structure in the Sistan region. [ABSTRACT FROM AUTHOR]

Natural disasters are responsible for causing significant damage to built environments and its consequent homelessness. This subject is notable in developing countries, specifically when they are located in earthquake-prone areas. After extensive destruction due to such incidents, authorities are confronted with numerous economic, social, and environmental complications in the implementation of housing solutions. Temporary housing (TH) is a short-term solution enabling communities to return to their routine activities by providing a minimum level of housing requirement. To accelerate the recovery procedure, resources should be carefully managed and a sustainable plan concerning economic, social, and environmental complexities should be developed. Therefore, this paper investigates the shortcomings of the existing TH solutions and uses prior experiences to propose a sustainable TH solution for an extensive area of Iran with a hot-arid climatic condition. Accordingly, the result is a TH system using earthquake rubbles in modular gabion containers. It was found that such a method could increase the occupants comfort level up to 8.61% while reducing a project's carbon footprint compared with the existing solutions. The proposed system assists authorities in confronting disasters with a more sustainable TH plan. [ABSTRACT FROM AUTHOR]

A better understanding of the interaction between shield supports, roof, and coal strata, along with the prediction of roof deformation and caving behavior is essential for successful longwall mining operations. The stability of a longwall face can be improved by caving of the roof strata, which can lead to decreasing the load on the powered supports and the magnitude of stress on the abutment pillar of the longwall face. This paper presents the application of the synthetic rock mass (SRM) numerical modeling approach for the simulation of the roof caving mechanism and the load on shield supports in a longwall coal mine in Iran. Using geological and geotechnical data from the mine, a two-dimensional SRM, based on the incorporation of a discrete fracture network into a bonded particle model, was used to simulate the coal seam and the jointed roof strata. The results of the numerical models were validated by comparing the span of first caving, caving height, and load on the support shields to field measurements, observations, and previous studies. The proposed numerical approach can be utilized as a reliable tool in the design and safe operation of a longwall panel with a better understanding of the caved, damaged, and deformed zones above it. [ABSTRACT FROM AUTHOR]

This paper proposes a multiobjective optimization approach for a preventive maintenance scheduling problem. To model this problem, an optimization model was developed by considering two objective functions: minimizing maintenance cost associated with the preventive tamping cost, machine preparation cost, and possession cost during time scheduling, as well as minimizing the total loss of remaining useful life (LRUL) over a given planning horizon. The applicability of the model was tested with the strength Pareto evolutionary algorithm II (SPEA-II) and multiobjective particle swarm optimization (MOPSO) algorithms in a case study on a section of Tehran-Mashhad line in Iran for the planning horizon of three years. Finally, a sensitivity analysis was performed on the possession cost and maximum permitted train speed. The results showed that by increasing the maintenance budget up to 47.32%, the track capacity could be increased by 25% due to increased permitted speed. Moreover, by increasing the cost associated with track possession, the preparation cost was reduced by considering the opportunistic maintenance policy through the grouping track segments. [ABSTRACT FROM AUTHOR]

This paper adopts the water-energy nexus approach to investigate the economic impacts of costly energy-intensive water supply projects. An integrated modeling framework is proposed for the regional-scale management of water and energy resources that incorporates the energy input-output analysis (EIOA) within a hybrid genetic algorithm-linear programming (GA-LP) optimization model, maximizing the gross domestic product (GDP). As a general framework, the proposed approach captures the trade-offs between water and energy in the technologies used for the production of other goods and services than water and energy. The framework is used to evaluate the economic gains of the nonlocal water supply projects, including water transfer and desalination in the Kerman province of Iran, where water shortages loom. The model determines the optimal allocation of newly supplied water to the economic sectors given the energy and water prices, the structure of production sectors, local resource constraints, and economic sectors' production capacities. The production capacities of all sectors, except water and energy, are exogenously expanded by 50%, which is in line with the projected population growth over 25 years (project's lifetime). Results reveal that in the absence of water supply projects, Kerman's GDP grows at 35% over 25 years. Meanwhile, the implementation of water supply projects increases Kerman's economic growth by 5% but requires around 2 TW · h of additional electricity and 735 mcm of additional water. Results also indicate under the optimal condition found that the GDP is influenced more by water allocation policies and less by the amount of water supplied from the nonlocal water source, which highlights the significance of nonstructural measures. [ABSTRACT FROM AUTHOR]

Water dependencies and agricultural expansion have led to a remarkable increase in water demand. Proper management of water supply and demand is a crucial challenge in planning for sustainable development. Because the prevailing water allocation system in developing countries is based on low tariffs, particularly in the agricultural sector, a robust accounting cannot be implemented. The objective of this paper is to investigate the economic value of a change from gravity to drip irrigation using groundwater resources. It is implemented in the Rafsanjan plain, in central Iran, where the irrigation practices lead to unsustainable use of groundwater. In this area, the allocator (water authority board) is a governmental agency that can receive funding from other governmental agencies to affect water use policies. Considering the benefits accrued to the allocator and farmers (benefit for all agricultural water uses), the optimal investment in converting gravity irrigation systems to drip irrigation is determined. An economic framework is proposed with two simulation models [Water Evaluation and Planning (WEAP) and Vensim] to evaluate the dynamics of the water use benefits. According to the results, with expenditures of $65 million/year over a 25-year horizon, the discounted benefit to allocator and farmers in the year 2011 would be $60.48 and $911.9 million, respectively. The framework outlined can provide a mechanism to allocate water in a more precise way as well as to determine the economic value of water in the agricultural sector. The proposed methodology can be applied to other geographic settings. [ABSTRACT FROM AUTHOR]

Deep excavations are commonly used in urban areas due to the extreme increase in ground worth. Stability and displacement of adjacent structures are two main design criteria in stabilized excavated walls. In this paper, one of the largest excavations in urban areas in Iran, the Farmanieh Project, is examined as a case study. The minimum and maximum depths of the excavation were about 26 and 45 m, respectively. Three different support systems including multistrand anchors, steel piles combined with multistrand anchors, and concrete piles combined with multistrand anchors were used. Owing to the limitation of lateral movement of adjacent buildings and urban facilities, the displacement of the excavated walls was controlled by precise instruments during and after the construction procedure to compare actual displacement and numerical analyses predictions. The results showed that if the construction procedure, including delays during the excavation procedure and vibration of construction machinery during drilling, the groundwater level, and soil properties were not properly taken into account, numerical analysis could be misleading in predicting wall displacement during deep excavations. Therefore, considering the factor of safety against displacement is as important as the factor of safety against failure. [ABSTRACT FROM AUTHOR]

The means for assessing what constitutes successful project delivery is a controversial topic in the literature, with many approaches and frameworks in play. This paper extends an existing three-dimensional (3D) integration model to include an assessment of triple-bottom-line (TBL) performance and applies it, for the first time, to a real-life case study. A subway station megaproject in Tehran, Iran, one of the busiest cities in the world, is retrospectively tested to evaluate its success. The new subway system is an important infrastructure project in Iran, and no research to date has evaluated its delivery from a project-management perspective. This paper provides governmental and private-sector agencies with a procedure to calculate the project delivery success (PDS) score for the construction of this subway or similar infrastructure projects, enabling a unique means to compare performance with other developments in Iran or elsewhere. From field data, it is shown by the researchers and verified by both the site project manager and client's representative that the subway's construction is an unsuccessful project. The findings quantify what could have been done, based on advice generated from the model, to deliver a successful outcome. The benefit of the utilized 3D integration model is its applicability to any project type or context, enabling them to be effectively compared and ranked by the percentage change between planned and actual PDS score. Given the introduction of TBL as a fifth core project constraint, an optimum solution can be found via the application of several heuristics (or rules) that define the boundaries within which a successful solution lies. The extended model contributes to knowledge through its ability to quantify success and optimize performance, ideally during the delivery of the project rather than as a postmortem exercise. [ABSTRACT FROM AUTHOR]

This paper develops an optimal, multistage operation of gated spillways for the Karkheh Reservoir, Iran. In each stage of the proposed method, the opening of the gates is proportional to the water level of the reservoir. Two novelties are introduced in this work. The first one is consideration of the absence of a spillway or the existence of blocked spillway gates as two operation scenarios. The second novelty is attributed to using improvement of dam safety as an objective function rather than a constraint of the optimization problem. A genetic algorithm (GA) was implemented for determining the optimal opening of gates to minimize downstream damages. The nondominated sorting genetic algorithm-II (NSGA-II) was applied to optimize the two objectives of minimizing downstream damages and reducing the probability of dam overtopping. This paper's results reveal that increasing the number of stages of gate opening improved the value of the objective functions. On the other hand, the lack of spillways or blocked spillways increases the risk of dam overtopping for long return periods. [ABSTRACT FROM AUTHOR]

In this paper, network resilience is quantified by generalization of various notions used in the mathematical theory of network resilience. This algorithm is then used to create a quantitative framework for the resilience characterization of high-pressure natural gas networks. The key concepts are the notions of a network with associated delivery function and delivery importance. No model is available in the literature to measure the performance of high-pressure natural gas networks. In this paper, a new index measuring delivery importance of a gas network is proposed to evaluate the resilience of the entire network. The methodology can be used to consider and quantify the effects of any type of natural disasters such as earthquake and fire, or artificial hazards such as deliberate attacks on the system that may lead to the disruption of the system. The principles and theories applied to the natural gas supply and distribution network in this study can also be applied to other infrastructures that are interconnected and operate as a network, such as the electrical power and water supply and distribution systems. Furthermore, the present paper shows the characteristics of production and demand of natural gas in Iran and provides a databased estimation of the future growth in production and consumption that is used in assessment of the resilience at a specific time in future. [ABSTRACT FROM AUTHOR]

Increases in greenhouse gases emissions have encouraged the replacement of fossil fuels with renewable energy sources. This paper investigates the potential of wind energy as a renewable resource for producing agricultural water in Eghlid city, Iran. The purpose of the optimization model herein considered is to maximize the net benefit from crop production by selecting an optimal cropping pattern. This paper’s results demonstrate that wind energy can be efficiently applied to provide irrigation water and optimize cropping patterns. Specifically, the application of wind energy to withdraw irrigation water increases agricultural production benefits in the amount of 1,254 million Rials (US$45,000). [ABSTRACT FROM AUTHOR]

Ongoing changes in global climate are expected to alter the hydrologic regime of many river basins worldwide, expanding historically observed variability as well as increasing the frequency and intensity of extreme events. Understanding the vulnerabilities of water systems under such uncertain and variable hydrologic conditions is key to supporting strategic planning and design adaptation options. In this paper, we contribute a multiobjective assessment of the impacts of hydrologic uncertainty on the operations of multipurpose water reservoirs systems in arid climates. We focus our analysis on the Dez and Karoun river system in Iran, which is responsible for the production of more than 20% of the total hydropower generation of the country. A system of dams controls most of the water flowing to the lower part of the basin, where irrigation and domestic supply are strategic objectives, along with flood protection. We first design the optimal operations of the system using observed inflows and evaporation rates. Then, we simulate the resulting solutions over different ensembles of stochastic hydrology to partition the impacts of streamflow and evaporation uncertainty. Numerical results show that system operations are extremely sensitive to alterations of both uncertainty sources. In particular, we show that in this arid river basin, long-term objectives are mainly vulnerable to inflow uncertainty, whereas evaporation rate uncertainty mostly affects short-term objectives. Our results suggest that local water authorities should properly characterize hydrologic uncertainty in the design of future operations of the expanded network of reservoirs, possibly also investing in the improvement of the existing monitoring network to obtain more reliable data for modeling streamflow and evaporation processes. [ABSTRACT FROM AUTHOR]

Identifying the criteria affecting multifamily housing and comparing different construction systems using these criteria to determine the optimal construction method based on a powerful decision-making technique can considerably help optimize multifamily housing, create more incentives for private contractors, and achieve ultimate success in multifamily housing projects. In this paper, 15 effective criteria for industrialized multifamily housing were identified through interviews and questionnaires. The alternatives of multifamily housing were then detected, and a model that could determine the best building method considering the criteria was developed through the analytic network process (ANP) technique. The reason for using the ANP technique was to organize the decision-making process in terms of a scenario affected by multiple independent factors. Contractors, consultants, owners, and those who are concerned with the issues related to industrial building will be the beneficiaries of this study. [ABSTRACT FROM AUTHOR]

This paper evaluates the performances of two long-term prediction approaches for streamflow and riverine total dissolve solids (TDS) and compares their results with observed data and with short-term predicted values. The future values predicted by the first, long-term, prediction approach (Approach 1) depend on data corresponding to time steps prior to the prediction time step. The future values predicted by the second, long-term, prediction approach (Approach 2) depend on data comprised within the observational period. Each long-term prediction approach calculates streamflow and TDS over a 12-month period ranging from April through March (Scheme 1) and by agricultural water year (December through November, Scheme 2). Genetic programming (GP) is implemented for long-term prediction. Prediction is applied to the streamflow and TDS of the Karoon River in southwestern Iran. The long-term Approach 1 was found to be more accurate than the long-term Approach 2 judged by the values of several diagnostic statistics. The root mean square error (RMSE), correlation coefficient (R2), and Nash-Sutcliffe efficiency (E) statistics of long-term predictions of streamflow and TDS with Approach 1 are lower than those obtained with the long-term prediction Approach 2 for April-March and for the agricultural water-year predictions. It is concluded that prediction of the Karoon River's streamflow and TDS is best accomplished using GP in combination with the long-term prediction Approach 1. [ABSTRACT FROM AUTHOR]

This work presents a methodology for extracting optimal operational rules for selective reservoir water withdrawal by considering fixed levels of reservoir water outlets for thermal control. The outlet water temperature of the Karkheh reservoir, Iran, is simulated with the CE-QUAL-W2 model. A data-mining model (the LIBSVM model) is applied as a surrogate model of the CE-QUAL-W2 model and coupled with a genetic algorithm (GA), resulting in the LIBSVM-GA algorithm. The selective withdrawal approach considered four fixed reservoir outlets, located at 120, 140, 163, and 181 m above sea level, to account for reservoir thermal stratification. This paper’s methods are evaluated with nonselective and selective withdrawal operations through different scenarios in which single outlet, fixed withdrawal proportions, fixed monthly variable proportions, continually variable (10-day) proportions using total monthly LIBSVM input data, and continually variable (10-day) proportions using separated monthly LIBSVM input data are considered. The highest outlet (at 181 m) was found to be the best level for the nonselective withdrawal scenario. The best selective withdrawal operations scenario was the continually variable (10-day) proportions using separated monthly LIBSVM input data, which minimize the root-mean-square deviation (RMSD) between upstream and downstream temperatures during the operating period. [ABSTRACT FROM AUTHOR]

Stochastic dual dynamic programming (SDDP) is a widely used technique for operation optimization of large-scale hydropower systems in which reservoir inflow uncertainty is modeled with discrete scenarios produced by statistical time series models, such as the family of periodic auto-regressive (PAR) models. It is a common practice in statistical modeling of hydrologic time series to fit a well-known probability distribution (usually normal distribution) to the data by applying proper transformation. Box-Cox transformation is a commonly used transformation in the case of normal distribution fitting. The convexity requirement of SDDP means that nonlinearly transformed time series cannot be used for statistical inflow model calibration. In this paper, a linear approximation is proposed to estimate the expected value of the next stage inflow. In the proposed approach, next-stage inflows are estimated by a model that uses transformed time series. Furthermore, using the proposed linear approximation, it is shown that it is possible to utilize the time series transformed by Box-Cox transformation for scenario generation in SDDP. The Karoon multireservoir system in Iran has been used as a case study in order to show the effectiveness of the proposed method. Some concluding remarks have also been provided by comparing the results of the two SDDP models, with and without the proposed linear approximation. [ABSTRACT FROM AUTHOR]

Premature deterioration of civil infrastructure structures in the harsh environmental conditions of marine regions (high humidity, high thermal variation, acidic attacks, high reactivity chemical reactions, improper usage, and natural disasters) leads to the reduction of service life of these structures. Failures in the rehabilitation process have been observed are primarily attributable to insufficient rehabilitation treatment, improper selection of repair materials, and incorrect repair implementation on the structures themselves. To design a suitable repair solution, it is essential that the physical, mechanical, chemical, and electrochemical properties of the repair materials and base (substrate) concrete match properly. In this paper, a novel approach for selecting proper mix design for repairing and maintaining deteriorated concrete structures located in the marine regions of southern Iran has been proposed using multi criteria decision making (MCDM) methods. The technique of random generation (RG) has also been used for uncertainty analysis on the final results. The results of the case study showed that the proposed methodology can be used as a proper tool for the decision making process in similar repair projects. [ABSTRACT FROM AUTHOR]

A multiobjective programming model is proposed for optimal allocation of surface and groundwater resources under water deficits in arid and semiarid regions. This paper considers a biobjective problem in water allocation to agricultural areas by using a non- dominated sorting genetic algorithm (NSGAII) as a multiobjective optimization method. Accordingly, there are two maximization objectives: (1) net benefit and (2) relative water use efficiency. Moreover, the optimized results of the aforementioned objectives have been determined to verify NSGAII solutions. Groundwater discharge, economic parameters, and evapotranspiration is formulated as three groups of constraints are linked together by the appropriate linear mathematical functions. The applicability of the irrigation scheduling is evaluated in the ex- perimental field located at Baghmalek plain, Khuzestan province, Iran. The values of crop factors for different growth stages were estimated to obtain the production functions of wheat, barley, rice, maize, melon, tomato, onion, vegetable, and bean. The results showed that the model did not suggest deficit irrigation for melon and tomato during the middle stage. Overall, incorporating multiobjective optimization techniques using NSGAII can effectively improve precision in irrigation scheduling. [ABSTRACT FROM AUTHOR]

In this paper, fluctuation in reservoir water quality is simulated and evaluated upon the sudden entry of a biological load. By using Version 3.2 of the two-dimensional quality simulation software CE-QUAL-W2, Iran's Karaj Reservoir is simulated, and a biological pollutant with coliform index is considered as the level of the pollutant. By considering factors involved in dispersion, advection, and decay of coliform, nine factors (nine sets of scenarios) are defined, and their influences on the pollution behavior are investigated. To investigate further, pollutant behavior is evaluated in various scenarios: water release, level of water withdrawals, input pollutant load volume, coliform decay rate, stored water volume in the reservoir, entry location of pollutant load, effect of water temperature on coliform decay, inflow to reservoir, and coliform sedimentation rate. Results show that some factors affect the pollutant behavior significantly, such as stored water volume in the reservoir and entry location of the pollutant load, so that the main changes in released pollution concentration appear with a decrease and increase of 25% in reservoir storage volume. Also, the closer the pollutant load entry location to the reservoir outlet, the higher the released pollution concentration. Maximum pollution released from the reservoir in the condition of entry of pollutant load in the lower third of the reservoir relative to the entry of pollutant load in the upper third is 15 times more. [ABSTRACT FROM AUTHOR]

This paper addresses a possible decrease in flood damages by using structural methods and determines proper locations (layout) to construct protective levees and height of levees (design of levees) in high-risk areas. Because of discontinuity of the objective function and a large number of decision variables, the optimization uses the genetic algorithm (GA). The simulation of the region is carried out with the Hydrologic Engineering Center's River Analysis System (HEC-RAS) model. The GA is employed to maximize the benefit of flood control and also to minimize the cost of protective levees' construction. Thus, the fitness function of the algorithm maximizes the net benefit of the project. After a sensitivity analysis, mutation and crossover probability are assumed to be 0.03 and 0.7, respectively. Thus, 1,000 generations and 98 chromosomes for each run are considered. The optimization model is run 5 times for floods with return periods of 50 and 100 years. Furthermore, the algorithm is used to evaluate flood damages in the Sarm and Khoor Abad River, located in the Qom province of Iran. Project net benefits resulting from the optimization model for rivers using 100-year flood exceed those for a 50-year flood. Results indicate that construction of protective levees reduces the rate of damages up to 99% in comparison with a nonconstruction of levees scenario. By taking into account the construction cost of levees, net benefits decrease by 0.97% and 1.1% for floods with 50-year and 100-year return periods, respectively. [ABSTRACT FROM AUTHOR]

The original paper used the modified AIC for selection of the best time series model HT ht (3) where HT ht and HT ht are the parameters of the stochastic model; HT ht = time independent uncorrelated series; and HT ht = number of samples for training of testing stages. In Eq. (3), by considering HT ht , these equations will be similar. [Extracted from the article]

Seasonal demand variation is a somewhat neglected aspect of transit demand. Many cities worldwide experience seasonal variation of passenger demand that deserves not only changes of service frequency, but also and often more importantly, changes in the transit network of routes. Literature dealing with optimal bus networks shows that it is an non polynomial (NP)-hard complexity problem with the demand being the most important variable affecting the network. Thus, the bus network of concern should be robust from the optimization perspective when a new demand arises. This paper introduces a model and a solution algorithm to take into account the variation of passenger demand in the design of bus networks. The solution algorithm developed is a hybrid method that optimizes the design of a bus network at the route and network levels. The model was applied to the city of Mashhad in Iran with a population of over 3.2 million and 20 million visitors annually. The results are promising and demonstrate how to determine the best single network of bus routes to suit variable passenger demand. [ABSTRACT FROM AUTHOR]

Research has revealed the impacts of climate change on the hydrologic cycle. These impacts are intensified in the urban water system due to special characteristics of urban watersheds, such as a high percentage of impervious areas and the presence of a microclimate. A slight change in rainfall intensity and duration can cause severe floods, with a significant incremental increase in life and property losses. Therefore, it is a key issue to modify the urban watershed characteristics in a systematic way to deal with these probable changes. In this paper, a multicriteria optimization model is developed to select best management practices (BMPs) for flood management in urban watershed systems. The addressed criteria include maximizing reliability of the drainage system, as well as minimizing flood damages and BMP costs. A new reliability index for dealing with floods is suggested in this study that considers both severity and duration of flooding. The optimization model is solved using a two-stage multicriteria decision making method which employs the nondominated sorting genetic algorithm II (NSGA II) and data envelopment analysis (DEA) for the selection of best alternatives. The performance of the suggested model is tested in an urban watershed located in the northeastern part of Tehran, the capital of Iran. The drainage system of this watershed is simulated using the storm water management model (SWMM) developed by United States Environmental Protection Agency (USEPA). The climate characteristics of this region are simulated under a climate change scenario based on Hadley Center Coupled Model, version 3 General Circulation Model (HadCM3 GCM) outputs. The rainfall events, with flooding potential, are determined and the optimization model is used to select the best BMPs for flooding conditions. The results show the important value of using the proposed algorithm for reducing flooding volume and increasing the drainage system's reliability. The results show further investigations are needed for real case applications to incorporate the uncertainties in climate change impacts. [ABSTRACT FROM AUTHOR]

The railroad blocking problem (RBP) is an important decision for freight railroad companies. The objective of this problem is to minimize the costs of delivering all commodities by deciding which interyard blocks to build and specifying the assignment of commodities to these blocks. In this paper, a mathematical model is presented for the RBP on Iran Railways. Its decision variables identify blocking scheme and demand assignment to these blocks. The RBP in medium and large sizes is not solvable with any commercial software available in the market. Therefore, a solution method based on tabu search algorithm is proposed for the suggested model. For evaluating the proposed algorithm, several simulated test problems are randomly generated and solved. The obtained results on the test problems are compared with those of solutions generated by CPLEX software. The comparison shows high efficiency and effectiveness of the proposed algorithm. The proposed model and solution method are applied to build a blocking plan for the Iranian railway. [ABSTRACT FROM AUTHOR]

One of the most aggressive environments for concrete is in an industrial area such as a petrochemical complex compound. In this area, exposure to highly corrosive materials such as ammonium nitrate, high carbonation rates (resulting from increased concentration of carbon dioxide (CO2) in industrial environments, and environmental conditions (such as relative humidity and temperature fluctuations) can collectively contribute to weakening the durability of concrete. This paper presents a study of corrosion damage of concrete and the embedded reinforcing steel of a 44-year-old nitrate prill tower of a petrochemical complex located in Shiraz, a city in southern Iran. After a thorough visual inspection and observing different deterioration mechanisms, a comprehensive set of conventional experiments to assess the durability of reinforced concrete was performed. Various degrees of deterioration were associated with different exposure conditions along the tower. Results indicated that the concrete had been severely decalcified up to 3 cm from its surface. However, reinforcement corrosion was negligible. Results moreover show that exposure to ammonium nitrate solutions was the primary reason for the high deterioration of the concrete of the tower. [ABSTRACT FROM AUTHOR]

Coating the walls with reinforced concrete layers is a conventional method of strengthening masonry structures in Iran. However, because of the lack of analytical and experimental information about the behavior of strengthened masonry walls with this method, the design of these walls is generally conducted based on empirical relations and decisions that may result in uneconomical or underdesigned strengthening details. This paper aims to develop a rational method for design and seismic evaluation of unreinforced masonry walls strengthened with reinforced concrete layers. In the proposed method, four failure modes are considered for these walls, and the strength relations and acceptance criteria for each of them are provided in accordance with FEMA 356 and ASCE 41 relations for reinforced concrete and masonry walls. The accuracy of the proposed method in predicting the nonlinear behavior and governing failure modes of the strengthened walls is validated by comparing the results with available experimental and performed numerical results. [ABSTRACT FROM AUTHOR]

Evapotranspiration is an integral part of the hydrologic cycle and an important component in water resource development and management, especially in the arid and semiarid conditions such as those found in Iran in which water resources are limited. The standard Food and Agricultural Organization of the United Nations (FAO)-56 Penman-Monteith (PM) equation requires several meteorological inputs for estimating reference evapotranspiration (ETo) that are not usually available in most of the stations. This paper investigates the potential of the adaptive neuro-fuzzy computing technique (ANFIS) for daily reference evapotranspiration modeling under arid conditions from limited weather data. The gamma test technique is applied to find the best input combination and number of sufficient data points for the model calibration. The training and testing data sets are chosen on the basis of the K-fold method of cross-validation to obtain the optimal classifier. The estimates of ANFIS models are compared with calibrated FAO-56 reduced-set PM ETo approaches and some calibrated empirical ETo equations such as Hargreaves, Priestley-Tailor, Makkink, and Blaney-Criddle equations. The FAO-56 full-set PM is adopted as the reference ETo equation, and it is applied to calibrate other ETo equations and ANFIS models. The comparison results indicate that when similar meteorological inputs are used, the ANFIS models performed better than all the methods pursued. This fact strongly suggests using ANFIS technique as an accurate ETo estimator method even in the absence of complete weather data. The minimum required data to construct a good ANFIS model under arid conditions are the minimum and maximum air temperatures and wind speed data. [ABSTRACT FROM AUTHOR]

Walking has an important role in improving public health. In the last decade, there has been a growing body of literature in public health, transportation, and urban design, which has analyzed the role of the built environment on physical activity, typically walking. Although these issues have received considerable attention in developed countries, few studies exist in developing countries such as Iran. The present study is the first study in the capital city of Iran: Tehran. This paper aims to analyze the objective measuring of the built environment in relation to walking in some neighborhoods of Tehran city. The results are then compared with the level of self-reported walking among elderly people in the study area. The results revealed that elderly people who live in high-walkable neighborhoods walk more frequently than those who live in low-walkable neighborhoods regardless of their socioeconomic status. [ABSTRACT FROM AUTHOR]

Estimation of evaporation, a major component of the hydrologic cycle, is required for a variety of purposes in water resources development and management. This paper investigates the abilities of genetic programming (GP) to improve the accuracy of daily evaporation estimation. In the first part of the study, different GP models, comprising various combinations of daily climatic variables, namely, air temperature, sunshine hours, wind speed, and relative humidity, were developed to evaluate the degree of the effect of each variable on daily pan evaporation. A dynamic modeling of evaporation was also performed, with the current climatic variables and one of the previous variables, to evaluate the effect of their time series on evaporation. In the second part of the study, the estimated solar radiation data were used as input vectors instead of recorded sunshine values. Statistics such as correlation coefficient (R), root mean square error (RMSE), coefficient of residual mass (CRM) and scatter index (SI) were used to measure the performance of models. Tthe dynamic model approach was shown to give the best results with relatively fewer errors and higher correlations. To assess the ability of GP relative to the neuro-fuzzy (NF) and artificial neural networks (ANN), several NF and ANN models were developed by using the same data set. The obtained results showed the superiority of GP to the NF and ANN approaches. The Stephen-Stewart and Christiansen methods were also considered for comparison. The results indicated that the proposed GP model performed quite well in modeling evaporation processes from the available climatic data. The results also showed that the estimated solar radiation data can be applied successfully instead of the recorded sunshine data. [ABSTRACT FROM AUTHOR]

Dependency of water demands on the climate variation occurs especially in regions where agricultural demand has a significant share of the total water demands. The variability between demands that are based on annual climate conditions may be larger than the uncertainty associated with other explanatory variables in long-term operation of an irrigation dam. This paper illustrates certain benefits of using variable demands for long-term reservoir operation to help manage water resources system in Zayandeh-rud river basin in Iran. A regional optimal allocation of water among different crops and irrigation units is developed. The optimal allocation model is coupled with a reservoir operating model, which is developed based on the certain hedgings that deals with the available water and the water demands mutually. This coupled model is able to activate restrictions on allocating water to agricultural demands considering variation of inflow to the reservoir, variation of demands, and the economic value of allocating water among different crops and irrigation units. Using this model, long-term operation of Zayandeh-rud dam is evaluated considering different scenarios of inflow to the reservoir as well as agricultural demands. The results indicate that the use of operating rules which consider variable demands could significantly improve the efficiency of a water resources system in long-term operation, as it improves the benefit of Zayandeh-rud reservoir operation in comparison with conventional water supply approaches. [ABSTRACT FROM AUTHOR]

The consideration of delay at signalized intersections improves the accuracy of equilibrium flows obtained from traffic assignment models. This delay depends not only on physical specifications of the intersection, intersection signal timing, and traffic volume and its composition but on drivers’ behavior and specific traffic culture in each country. This paper proposes a delay function for traffic assignment models, which considers the special drivers’ behavior in Iran. Unlike the existing models such as the Highway Capacity Manual model, the proposed delay function has modest data requirements on intersection characteristics, and this ensures the easy use of this function in a real traffic assignment model. To evaluate the proposed function in a real network, the traffic assignment model of the city of Mashhad, Iran is used. In two different scenarios, the equilibrium flows obtained when the proposed function is applied and those obtained when a simple uniform delay function is used are compared to the observed traffic flows. In a comparative sense, the results show the better performance of the proposed function in estimating the equilibrium flows. [ABSTRACT FROM AUTHOR]

Six water authorities share the Sefidrud watershed in the northwestern region of Iran and resolving the conflict among them is one of the major challenges of the water division of the government. In this paper a group decision support system will be developed for identifying the criteria and their weights, needed for ranking water resource projects in this watershed. This model will be based on extending the ordered weighted averaging (OWA) as an aggregation operator. The order weights of this operator will be determined first by using the minimal variability method. Second, a new measure will be developed to quantify consensus among the stakeholders. It guides the supervisor of the group decision making problem to negotiate with stakeholders effectively in the conflict resolution process. Using extended OWA, 13 water resources projects in the Sefidrud watershed will be ranked. A simulation study will also be reported, where the dependence of the optimal decision on the uncertainty level is examined. In addition, a new sensitivity analysis model will be introduced for the combined goodness measures of the projects with respect to the optimistic degree of the supervisor. A new composite measure of goodness will also be defined to obtain reliable solutions. [ABSTRACT FROM AUTHOR]

A common method for assessing the energy potential of hydropower systems in Iran is the sequential streamflow routing with control on the energy-yield reliability. The method results in developing a reliability-based simulation (RBS) model that is used to analyze single-reservoir hydropower systems. In most of the cascade hydropower systems in the country, a single-reservoir RBS model is usually employed in the design and operation of each of the systems reservoirs. This paper presents a multireservoir RBS model considering the integrated operation of the systems. The model employs the general algorithm of the single-reservoir RBS model; however, with a single-period optimization submodel in determining releases from reservoirs during the system simulation. The objective function of the submodels minimizes the sum of reservoir releases and/or maximizes the sum of reservoir storages in each of the time periods, subject to a reliability constraint on the system’s energy yield. The single and multireservoir RBS models are applied in the Khersan hydropower system located in Iran as a case study. The multireservoir RBS, compared to the single-reservoir model, results in 7.9% excess firm-energy yield in reliability of 90%. [ABSTRACT FROM AUTHOR]

One of the major error sources in the global positioning system (GPS) is ionospheric delay (refraction). This delay is frequency dependent and therefore can be removed by dual frequency receivers. Using eight coefficients transmitted as part of the navigation message a correction can be provided for single frequency users called the Klobuchar model. This model is expected to remove up to 50% of ionospheric delay. On the other hand all receivers cannot recover coefficients. This paper is a report on our attempt at the GPS site of Esfahan University to model the zenith ionospheric delay from weighted observation of the L1 code and carrier phase, made with a 12-channel Leica System 500 receiver. The results will be compared with IGS and Klobuchar model estimates. [ABSTRACT FROM AUTHOR]

This paper reports on a study undertaken to investigate the earthquake performance and assess the seismic vulnerability of post-Islamic monumental structures in Iran. These structures are primarily of brick masonry construction, though some notable stone and mud-brick structures also exist. The structures are first classified according to their structural forms. A review of the available historical and recent sources on the earthquake behavior of different structural forms is then conducted. A second classification of the structures is subsequently made according to their seismic vulnerability. By estimating the location intensity for a large number of past and present structures, subjected to earthquakes in the last millennium, “damage” and “survival” intensity levels are calculated for different structural groups. Based on the estimated damage and survival intensity levels, an intensity scale is proposed for the post-Islamic historical structures in Iran. [ABSTRACT FROM AUTHOR]

The Tehran metropolitan area is one of the mega cities of the world and has an annual domestic water consumption close to one billion cubic meters. The sewer system mainly consists of traditional absorption wells. Therefore, the return flow from the domestic consumption has been one of the main sources of groundwater recharge. Some part of this sewage is drained into local rivers and drainage channels and partially contaminates the surface runoff and local flows. These polluted surface waters are used in conjunction with groundwater for irrigation purposes in the southern part of the Tehran. In this paper, a systematic approach to surface and groundwater resources modeling in the study area, with its complex system of water supply, groundwater recharge, and discharge, is discussed. A dynamic programming optimization model is developed for conjunctive use planning. The objective function of this model is developed to supply the agricultural water demands, to reduce pumping costs, and to control groundwater table fluctuations. To develop the response function of the aquifers located in the study area, a mathematical model for simulation of the Tehran aquifer water table fluctuations has been developed and calibrated with the available data. Different scenarios are defined to study the long-term impacts of the development projects on conjunctive use policies and water table fluctuations. Comparison of the results showed how significant is the effects of an integrated approach to the surface and groundwater resources allocation in Tehran metropolitan area. The proposed model is a useful tool for irrigation planning in this region. [ABSTRACT FROM AUTHOR]

Design of water distribution networks (WDNs) is classified as a large combinatorial discrete nonlinear nondeterministic polynomial-hard (NP-hard) optimization problem. The main concerns associated with the optimization of WDNs are related to the nonlinearity of the discharge–head loss relationships for pipes and the discrete nature of pipe sizes. This paper proposes a new evolutionary algorithm, called fittest individual referenced differential evolution (FDE), which is significantly more efficient and reliable than other algorithms for optimization of WDN designs. The fundamental structure of FDE is similar to conventional differential evolution (DE), although the functions of the mutation and crossover operators are to exploit good solutions, and explore very different solutions, respectively, and counting and restarting mechanisms are introduced to identify and avoid local optima. These features are beneficial in WDN design because such problems may have an array of local optima that are far from one another, making finding the global optima difficult. The mutation and crossover operators are developed to accelerate convergence and, although the optimal mutation and crossover parameters may vary among networks, the efficiency of the algorithm reduces the need for adaptive parameters or population size. A sensitivity analysis is conducted for algorithm parameters, as well as counting and restarting limits, based on eight evolutionary algorithm (EA) benchmark test problems, and the efficiency of the FDE for solving 2- and 10-dimensional versions of these problems is demonstrated using the most effective values of the parameters and limits. FDE-based optimal designs of four benchmark networks—the Two-loop, Hanoi, and New York WDNs and the Balerma Irrigation Network—show that on average, a minimal number of function evaluations (or hydraulic simulations) is required to reach the best known optimum, which is less than or equal to 600 in all cases for the first three networks. Furthermore, a detailed application of FDE to a large-sized network, that for the City of Farhadgerd, Iran, shows that FDE is significantly more effective than other EAs in terms of its speed of convergence and reliability. [ABSTRACT FROM AUTHOR]

Gonbad-e Qābus, with a height of 52.8 m that makes it the tallest pure-brick tower in the world, located in the northern part of Iran, represents one of the most magnificent structures of the early Islamic centuries. This structure is still standing among the chaos of urban life and construction, catching the eyes of beholders even from far distances. This paper summarizes the historical and architectural background of this monumental structure and the important restorations carried out mainly in the past century. Various types of existing and potential structural and architectural damages are classified and elaborated in detail, and for each problem, a series of proposed solutions are presented. Utilizing the nonlinear finite-element simulations and equivalent lateral static force method, it is concluded that Gonbad-e Qābus is vulnerable to seismic demands with a return period of 475 years; therefore, retrofit strategies should be considered to improve its seismic performance. [ABSTRACT FROM AUTHOR]

Water resources management is a challenging problem in Iran and in many other locations because of the unbalanced temporal and spatial distribution of available water and demands. Interbasin water transfer, in which water is transmitted from a basin with high water availability to a neighbor basin with high water use, has been proposed as a solution to water scarcity. Because of the various decision-making factors, studies of interbasin water transfer projects have been presented as complex and difficult in the literature. In this paper, an optimum design for the capacities of the Behesht-Abad interbasin water transfer system, from the upstream Karoun basin to the Gavkhooni basin in central Iran, has been studied using a simulation-optimization approach in which particle swarm optimization (PSO) is coupled with the river basin simulation model, to find the optimum values for decision variables. In another approach, by use of multicriteria decision making (MCDM) and quantifying selected criteria in the source and target basins, the most beneficial scenario for water transfer is selected by prioritizing six possible alternatives. Results obtained by both PSO-MODSIM and MCDM approaches are close to each other and show that under conditions consistent with recent drought years, the optimum capacity of the water transfer tunnel is obtained to be a maximum of 45% of the capacity under conditions consistent with long-term historical discharges of the rivers. [ABSTRACT FROM AUTHOR]