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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]

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]

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]

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]

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]

Frequent catastrophic earthquakes have highlighted the significance of postearthquake recovery and reconstruction (PERR) planning, a dynamic and inclusive process which encourages the building of more resilient communities. This paper aims to provide some meaningful lessons for quake-prone countries through a review, comparison, and discussion of PERR planning success and failure factors in the 1994 Northridge earthquake in the United States, the 1995 Kobe earthquake in Japan, the 2003 Bam earthquake in Iran, and the 2008 Wenchuan earthquake in China. The authors then provide some guidance for PERR planning in key areas such as formulating predisaster planning, enabling participatory planning, capacity building for public involvement, schedule control, process coordination, developing catastrophe insurance, protecting vulnerable groups, and assessing plan quality. Further in-depth studies could be done to conduct broader crossnational comparisons on some important specific aspects, such as predisaster planning, participatory planning, and plan implementation. [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]

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]

Seawater intrusion is a common problem in coastal aquifers and can be intensified by various factors, such as unplanned groundwater extraction. Hence, making appropriate decisions for coastal groundwater management is essential to prevent excessive seawater intrusion, although the uncertainties of this procedure can undermine the reliability of obtained results and consequently affect proposed decisions. To address such challenges, this study presents an uncertainty-based decision model based on a combined simulation-optimization framework and parallel processing technique. In this model, the SUTRA numerical simulation model is combined with an evolutionary algorithm of continuous ant colony optimization, while Monte Carlo simulation is used to consider the uncertainties in the permeability of porous media. Two sets of probabilistic management problems are formulated for maximizing groundwater extraction and controlling the seawater intrusion in a real case coastal aquifer of Ajabshir, Iran. The results indicate that a 46% increase in groundwater extraction is possible for a low-exploitation-stress period of the year. Moreover, using a parallelization technique with 15 threads, the computational time of the decision model is cut in half. [ABSTRACT FROM AUTHOR]

This study aims at identifying suitable sites for underground or subsurface dams using a spatial multicriteria evaluation (SMCE) for water supplies in an arid watershed in southwestern Iran. Specific constraints and three groups of criteria were used in developing a spatial decision model. Constraints included slope, fault, land use, and geology. Site characteristics were classified based on slope, geomorphology, infiltration, precipitation, geology, and distances from roads, from rock materials sites, from faults and springs, from rivers and streams, and from various land uses. A criteria tree was designed and standardized using Boolean logic and fuzzy membership on factors. Factors were weighed by both ranking and direct methods. Finally, the composite index map (CIM) was used to identify three best sites. With valley shape consideration, Site2 was the most suitable for construction of a subsurface dam. Interpretation of valley profile, optimum decisions on subsurface dams, and multicriteria for site selection can be used in water resource planning. [ABSTRACT FROM AUTHOR]

Drought quantification is a decision-making approach for water resources planners and managers. There are different statistical methods for regional quantification of droughts, depending on the event being regionally discrete or continuous. Calculating a drought index in the measured grid points of a given region is a prerequisite for the regionalization process of drought by these methods. The aim of this study is the regional analysis of the streamflow drought using the multivariate technique of principal components analysis (PCA). To this end, the streamflow drought index (SDI) was calculated in the seven hydrometric stations of the Sefid-Rud basin in Iran for the period of 1984-2013 in seasonal (winter, spring, summer, and autumn), semiannual (October-March and May-September), and annual (October-September) time scales. Regional monitoring of the SDI was carried out using the PCA technique summarizing the SDI series of all stations into a new series, the so-called the multivariate streamflow drought index (MSDI). The MSDI series at each time scale were analyzed from several statistical aspects. Results showed that there are relatively high correlations between the SDI series of the stations for given time scales. The first principal component (PC1) explains 58-85% of the regional variations of the SDI series at the mentioned time scales. The MSDI series at multiple time scales follow all stations' SDI fluctuations and appropriately monitor droughts that occurred in the region, especially in long dry periods. The dry and wet severity classes derived from the MSDI series greatly corresponded to those of the SDI time series on different stations. The highest percentage of correspondence between MSDI and SDIs was calculated for the semiannual time scale and the lowest for the spring season. [ABSTRACT FROM AUTHOR]

In this study, the trends in precipitation in the northwest (NW) of Iran were identified using the four different versions of the Mann-Kendall method, i.e., the conventional Mann-Kendall method (MK1); the Mann-Kendall method following the removal of the effect of significant lag-1 autocorrelation (MK2); the Mann-Kendall method after the removal of the effect of all significant autocorrelation coefficients (MK3); and the Mann-Kendall method by considering the Hurst coefficient (MK4). Identification of trends was carried out on different time scales (monthly, seasonal, and annual) using the precipitation data of 50 years from 1955 to 2004 of the sixteen stations selected from the NW region of Iran. The Theil-Sen method was used to estimate the slopes of trend lines of precipitation series. Results showed that: (1) on a monthly time scale, the statistically significant -statistics were negative for all but one (July) month; and the strongest negative (positive) precipitation trend-line slope among all the negative (positive) cases was found to be at Bijar (Kermanshah) station in NW Iran; (2) on a seasonal time scale, the median of trend-line slopes was found to be negative in all four seasons; the winter and spring season's precipitation series witnessed negative trends for almost all the stations using all four different versions of the MK test; and in the summer and autumn seasons, both upward and downward trends were observed for most of the sites of NW Iran; (3) in an annual time scale, all stations had witnessed negative trends using both the MK1 and the MK4 tests. However, application of the MK4 instead of the MK1 reduced the absolute value of the -statistic for most of the time series. The strongest negative annual trend-line slope was at Bijar station. Therefore, the observed decreases in precipitation in NW Iran in the recent half of the past century may have serious implications for water resources management under the warming climate with probably a higher rate of the population growth and the higher consumption of freshwater as a result of the rise in standards of living of the population of NW Iran. [ABSTRACT FROM AUTHOR]

The recent decrease in physical activity among youth, which has resulted in increasing obesity and in overweight individuals, has attracted global attention and a renewed sense of investigation in both public and academic circles. However, using active modes of transportation (AMT) to and from school can serve as a bulwark against inactivity and the increase in cases of obesity and excess weight. In an attempt to study and counteract this growing phenomenon, more than 4,700 questionnaires were distributed in 92 schools throughout Tehran in a random stratified sampling method according to location and gender differences, and 3,441 responses were received (72% response rate). Significant factors affecting each gender's propensity to choose active modes of transportation to and from school were separated and identified. Among females, 45% chose an AMT to school, and 52% did so for return trips home, both of which are higher than the males' propensity to choose AMT. Among males, 39% chose an AMT to school, and 46% did so for the way back. Female tolerance in active modes of transportation also proved to be greater than that of males such that with an increase in costly factors (e.g., increases in travel time), economic considerations (e.g., household car ownership), and tougher topography, females substituted away from AMT less than males. [ABSTRACT FROM AUTHOR]

A detailed investigation was carried out on a 50-year-old reinforced concrete jetty in a commercial port of Iran to assess the long-term performance as well as the structural condition. Destructive and nondestructive tests such as carbonation depth, electrical resistivity, chloride diffusion, X-ray diffraction, compressive strength, and water absorption were performed. The results revealed that the good quality of the concrete has protected reinforcement from corrosion. However, structural analysis showed minor weakness in some elements of the jetty; thus, consulting engineers finally decided to strengthen some elements with fiber-reinforced polymers. [ABSTRACT FROM AUTHOR]

A lysimeter study was conducted in the field in Karaj, Iran to investigate the effects of water table management on water quality of subsurface drainage effluents. Drain volumes, nitrate-N concentration, phosphorus concentration, and electrical conductivity of drain effluents were monitored during the growing seasons of alfalfa (Medicago scutellata). Totally 12 lysimeters consisted of four treatments were used in this study, of which nine of them were equipped with subirrigation (SI) and the other three with free drainage (FD) systems. Annual alfalfa (Medicago scutellata) was planted in all lysimeters. Water table levels were kept at 30 cm (SI30), 50 cm (SI50), and 70 cm (SI70) below the soil surface in SI-lysimeters and more than 100 cm below the soil surface in FD-lysimeters. The results of this 2-year study showed a significant reduction in nitrate-N concentrations in SI-lysimeters compared to FD-lysimeters. In 2005, the mean nitrate-N concentrations in drainage effluent were reduced by 84% in the SI30 and by 82% in the SI50, relative to FD. Similarly, in 2006, drain water depth and nitrate-N concentrations were significantly reduced relative to FD. The forage dry matter production from SI30 and SI50 were significantly higher than those from FD in both years. In 2006, the average of dry matter production was increased by 69 and 89% by the SI30 and SI50, respectively, relative to FD. The average electrical conductivity of drainage water was reduced in SI lysimeters compared to FD lysimeters that meet Iranian standard level (3 dS/m). There are no statistically significant differences in phosphorous concentration in drainage water of different treatments. Finally, the results of this 2-year study indicate that the water table management practices are economically and environmentally feasible in Iran in order to have a sustainable agriculture. [ABSTRACT FROM AUTHOR]

Presented herein is an attempt to put into practice the multicriteria decision making technique of compromise programming for a real urban water management case study in the city of Zahidan in Iran. Zahidan, the capital of Sistan and Balouchistan Province, faces serious water problems in terms of both quality and quantity. To satisfy future water demands, a long-distance water transmission project is being implemented. Compromise programming is applied to aiding decision makers in selecting the best possible alternatives for distribution of both available and the transmitted water in the city. The results obtained reveal that the method is capable of being employed by decision-makers for comprehensive urban water management studies. [ABSTRACT FROM AUTHOR]

The suitability of the project delivery system (PDS) selected for a project greatly influences the efficiency of project implementation. In Iran, traditional design-bid-build (DBB) is commonly used for highway construction projects; however, DBB leads to problems such as cost overruns, delays, and poor quality. This study aims to compare the performance of DBB with that of alternative contracting methods (ACM), including design-build (DB) and construction manager (CM) methods, for highway projects in Iran. A survey was conducted to determine the most important decision-making criteria for selecting the appropriate PDS to use in highway projects. The survey, conducted by postal questionnaire, aimed to empirically validate the reliability of the model. In the survey, all the conditions for imposing the effective criteria were considered, and ultimately a model using the analytical hierarchy process (AHP) was developed to rank the PDSs for highway construction projects in Iran. The results showed that DB is most often the optimal method. The research can be used to prepare a model that can help project owners make sound decisions about the best PDS. [ABSTRACT FROM AUTHOR]