Ali Akbar Akhtari

Weirs are among the most important hydraulic structures in water engineering, playing a key role in flow control and measurement, water level regulation, and ensuring hydraulic safety in open channels and hydraulic systems. Among various types of weirs, sharp-crested weirs have always attracted significant attention due to their simple construction, acceptable accuracy in discharge measurement, and wide application in open channels. However, channel width limitations and the increasing demand for higher discharge capacity have made the optimization of the geometric configuration of these weirs increasingly important. One effective approach in this regard is the use of inclined sharp-crested weirs combined with transverse crest slope modification, which can increase the effective crest length and improve hydraulic performance. In this study, the hydraulic performance of an inclined sharp-crested weir with a non-uniform transverse slope was numerically investigated. The main objective of the research was to evaluate the effects of the weir inclination angle and non-uniform transverse slope on flow patterns, velocity and pressure distributions, free-surface behavior, and the discharge coefficient. To achieve this goal, three-dimensional free-surface flow simulations were carried out using the FLOW-3D HYDRO software (version 2023R2). The RNG k–? turbulence model was employed to close the Reynolds-averaged Navier–Stokes equations, as it provides suitable accuracy for simulating three-dimensional turbulent flows, regions with high velocity gradients, and flow separation zones. The computational domain consisted of a three-dimensional model of the sharp-crested weir with different inclination angles and transverse slope configurations. Appropriate boundary conditions for inlet, outlet, walls, and the free surface were defined based on experimental conditions. Prior to the main simulations, a grid sensitivity analysis was performed to select an optimal mesh that ensured sufficient accuracy while maintaining reasonable computational cost. To validate the numerical model, simulation results were compared with available experimental data. Four different weir configurations with varying geometric and angular conditions were simulated. The comparison of upstream water depth between numerical and experimental results showed that the relative error was less than 2% in all cases, confirming the reliability and accuracy of the numerical model. The simulation results indicate that applying a non-uniform transverse slope to the crest of an inclined sharp-crested weir significantly affects flow behavior. Increasing the inclination angle enhances the effective crest length and increases discharge capacity, although a slight reduction in the discharge coefficient was observed in some cases. Furthermore, the results demonstrate that a variable transverse slope can lead to a more uniform flow distribution across the channel width, reduce secondary flows, and improve free-surface stability. Overall, the combined use of an inclined crest and a non-uniform transverse slope can be considered an effective approach for improving the hydraulic performance of sharp-crested weirs in hydraulic structure design.  

  In developing countries, construction waste accounts for a large part of urban waste, which, in addition to being very expensive to dispose of, has adverse consequences on the environment. Recycling construction waste not only helps to preserve natural resources and the environment, but also has economic justification by using scientific methods. In the present study, an attempt has been made to study the mechanical properties of construction waste at the laboratory level and to evaluate the possibility of reusing these materials in road construction as sub-base materials. For this purpose, 19 samples of mixtures including concrete, brick, ceramic and gypsum materials with different weight percentages were selected for the study. The results of the compaction tests showed that with increasing the amount of brick and gypsum in the mixtures, the tendency to absorb water in them and the optimum moisture percentage increase and the dry specific gravity of the mixture decreases. After conducting California bearing ratio tests on the mixtures, it was found that all 19 mixtures could be used as base layers. In addition, mixture 19 could also be used as base layers. Next, the mixtures with the highest and lowest CBR values ??were subjected to direct shear tests, the results of which indicated the existence of an internal friction angle and their high potential for engineering applications, including road construction. Finally, using genetic, particle swarm optimization, and differential evolutionary metaheuristic algorithms, the percentages of materials were determined to achieve the optimal mixture.

  Abstract In developing countries, construction waste accounts for a large part of urban waste, which, in addition to the high cost of disposal, also has adverse consequences on the environment. The volume of construction waste is so large that this issue is now a social and environmental problem not only in Iran but also in developed countries. Recycling construction waste not only helps to preserve natural resources and the environment, but also has economic justification by using scientific methods. Construction waste is the most common type of waste produced in the world. Therefore, insufficient attention to this type of waste can be raised as an environmental problem in the future. Today, the use of materials made from recycled construction waste is an important issue. The use of this type of waste (waste) can reduce the need to exploit natural resources. In the present study, the possibility of recycling these materials and using them directly as base or sub-base materials is investigated. For this purpose, after obtaining the necessary waste from the desired location and determining the waste compositions based on weight percentage (the lowest is 5 percent and the highest is 45 percent), 19 samples of the selected waste compositions were selected with different weight percentages, and then the necessary physical tests including grading, sand equivalent, modified density, elongation and splitting, water absorption, and abrasion were performed on the selected materials to examine the quality of recycled waste as road construction materials. The results show that the selected grading was in the coarse-grained range and it is necessary to modify the grading. The sand equivalent results indicate that it is usable for the sub-base layer. The density shows that the samples containing a higher percentage of gypsum and brick have a higher optimal moisture content and a lower maximum specific gravity. The elongation and splitting results indicate that these compositions are usable for the base and sub-base layer. The results of the water absorption test show that brick and gypsum have a higher water absorption capacity than concrete and ceramics. The abrasion results show that the selected materials with the selected percentage are not of good quality and the amount of concrete should be increased and the amounts of plaster and brick should be reduced. Keywords: waste, base, road construction, recycled materials, construction waste, physical properties.

This study presents a comparative evaluation of the effluent quality of the wastewater treatment plant in Ivan, Iran, over two consecutive years (2020 and 2021), employing the Effluent Water Quality Index (EWQI) based on the standards of the United States Environmental Protection Agency (EPA), the World Health Organization (WHO), and the Iranian National Standards. The EWQI was calculated using a dedicated code developed in the Python programming environment, and the obtained results served as the basis for quality assessment and analysis. Findings indicated that, according to the EPA and WHO criteria, the effluent quality in 2020 consistently remained within the “good” range, whereas in 2021, a substantial improvement in the second half of the year elevated the quality to the “excellent” level. In contrast, the Iranian National Standards, owing to their broader permissible ranges for chemical parameters and heavy metals, >Keywords: Entropy Weighted Water Quality Index (EWQI), wastewater treatment plant, EPA standards, WHO guidelines, Iran   

   Today, the issue of climate change and fluctuations and the anomalies resulting from it is one of the most important global issues. Detecting changes in precipitation and temperature is used as the primary evidence of climate change in many regions of the world. Therefore, in this research, by examining the changes in the rainfall of Kermanshah province in different time scales of the year, season and month, it was done to determine the cause of flooding in the part of the streets leading to Nobahar Blvd. Surface water collection networks are responsible for directing and transferring surface water caused by rainfall and daily use, but nowadays, due to the expansion of urbanization and the significant increase in impervious surfaces, this possibility has already become difficult and effective for them. With these transmission networks, Nobahar Boulevard faces many problems during rainfall and runoff. It is possible to help improve the conditions and satisfaction of the people of Kermanshah. And the unpleasant face of waterlogged streets, which causes people's dissatisfaction and also causes pollution to be removed from the city.

Abstract Research Aim: Tailings dams are built in the mining industry to manage and store the residual waste materials, known as tailings, that remain after the extraction and beneficiation of metallic and non-metallic ores. Tailings often contain toxic materials. This research involves the simulation of a localized tailings dam breach with a water pond, the investigation of the hydraulic characteristics of the flow, and the comparison of a tailings dam breach with and without lateral slopes. It also investigates the impact of different water surface elevations, locations, and breach widths on the flood and the volume of eroded sediment in a tailings dam's local failure. Research method: In this research, the two-dimensional HEC-RAS software, which utilizes shallow water equations, was used for the numerical simulation of laboratory tailings dam failure cases. For the validation of the simulation results against the laboratory data, the Mean Absolute Relative Error (MARE) and the coefficient of determination (R²) were employed. Findings: This research was conducted to investigate the pattern of bed scour, the amount of sediment transport, changes in the hydraulic quantities of the flow, and information about the floods resulting from local failures under different water surface elevations, locations, and breach widths. Conclusion: The Wu as the sediment transport function was most compatible with the experimental results. In the case of local failure far from the abutment, the shear stress and the Froude number were maximized after the localized dam breach in the downstream flow, which decreased over time with the reduction of the water surface elevation and began to increase at the edge of the scoured area. The side slope increased the scour by a factor of 1.3. Unlike the breach location and the lateral slope, the breach width and the water surface elevation significantly impacted the hydrograph pattern of the outflow resulting from the tailings dam failure. Ultimately, HEC-RAS was able to perform the simulation with relatively high accuracy, which could serve as an alternative to costly and time-consuming experiments. Keywords: Tailings dam, Dam break, Scour, Numerical simulation, HEC-RAS 2D

   Insert text here. Fatigue cracking is one of the main problems of asphalt pavements that affects the durability of the pavement. Self-healing ability is one of the factors that can lead to asphalt resistance against fatigue cracks caused by traffic loading and ultimately increase the fatigue life of asphalt pavement. Every year, a large part of road maintenance and repair costs are spent on fixing the damages caused by these cracks. Therefore, researchers are looking for ways to recognize and increase the use of self-healing capabilities to increase pavement life and reduce road maintenance costs. This research examines the effects of styrene-butadiene-styrene (  ) and carbon fibers (CF) on asphalt self-healing ability through the three-point bending test, and the effect of    and carbon fiber on the microwave heating process. Also, in this research, the temperature of the surface and inside of the asphalt samples has been investigated.   In line with this research, four types of asphalt samples were made, including asphalt without additives, asphalt with    additives, asphalt with CF additives, and asphalt with both    and CF additives. In this research, in order to evaluate and compare the self-healing in different asphalt samples, the ratio of secondary resistance to primary resistance is defined as healing index (HI). The results showed that carbon fibers cause a more uniform distribution of temperature and increase the heating speed of asphalt, but it has reduced the primary and secondary resistance of asphalt to a great extent compared to asphalt without additives.    improved the strength performance of asphalt samples to a great extent, so that the average initial flexural strength of samples made with    is about 180% of the average initial flexural strength of samples made without additives. Also,    decreased the average temperature of the surface and inside of the asphalt samples and made the temperature distribution weaker. These two additives did not increase the asphalt healing index compared to the asphalt without additives.   

   مهمترين قدم در راه آبرساني ساختمان­ها، تامين آب سالم و بهداشتي است. بيماري­هاي ناشي از آشاميدن آب آلوده بسيار خطرناك مي­باشند. كنترل كيفيت آب از نظر املاح محلول، رنگ، بو ومزه و باكتري­هاي موجود از لحاظ بهداشتي واجد اهميت حياتي است. مخازن عموما به منظور ذخيره آب پاك، ذخيره براي توزيع، گندزدايي، تامين فشار، جمع آوري، پمپاژ و يا تركيبي از اين موارد طراحي مي­گردد. مشكلات كيفيت آب در تاسيسات ذخيره­سازي را مي­توان بعنوان مشكلات ميكروبيولوژيكي، شيميايي و يا فيزيكي طبقه­بندي كرد. سن بيش از حد آب در بسياري از تاسيسات ذخيره­سازي احتمالا مهمترين عامل مرتبط با كاهش كيفيت آب است. انباشته شدن رسوب در مخازن مشكلات بالقوه در كيفيت آب وافزايش تقاضاي ضدعفوني كننده، رشد ميكروبي، كدورت آب و پوسيدگي كلر را به دنبال دارد. جهت بررسي بي­خطر بودن آب ذخيره بايد تحقيقاتي صورت گيرد. بسياري از ساختمان­ها داراي مخازن ذخيره آب در زيرزمين يا پشت بام هستند تنها در صورتيكه مخزن به درستي طراحي و نصب شده باشد و در شرايط خوبي نگهداري شود استفاده از آن بي­خطر خواهد بود.   در اين تحقيق با روش مشاهده و بازديد ميداني سعي شده است الزامات مربوط به مخزن ساختمان مورد مطالعه قرار گيرد. نتايج نشان داد كه بسياري از الزامات مربوط به اين مخازن در منطقه مورد مطالعه رعايت نشده است.

      Abstract Risky driving behavior is an important cause of physical, psychological, and financial injuries and is a major threat to public health. The present study aims to investigate the effects of psychological-social-economic pressures on risky driving behavior with the mediating role of resilience. This was a cross sectional design study, in which 219 male drivers aged 18-60 years were recruited from Khorramabad using sampling technique. The Socioeconomic status (SES) Questionnaire, DASS 21, CD-RISC-10, and Road Traffic Behaviours Questionnaire, were used. The analyses were performed using IBM    version 27 and SmartPLS 4 software. The model fit indices were good, SRMR = 0.05 and NFI = 95. The results obtained from structural equation modeling show a significant effect of socioeconomic status on risky driving behaviors (?=-0.199; T=3.04; P<.004), psychological status on risky driving behaviors (?=0.791; T=11.81; P<.001), psychological status on resilience (?=-0.255; T=2.26; P=.024), resilience on risky driving behaviors (?=-0.114; T=2.14; P<.033), and the non-significance of the effect of socioeconomic status on resilience (?=0.068; T=0.601; P=539) in the framework of the conceptual model of the present study.The findings of this study showed that resilience is a critical mechanism for improving residents’ sense of public health safety in drivers in Iran. Some certain guidance measures are provided to reduce public anxiety and fear while driving. Keywords

Purpose: Today, one of the most important problems of cities is the insufficiency of the tra  ortation system and urban traffic. With the expansion of the city of Ilam in the last few decades, the bus organization serves the citizens from the old stations with the same layout and number of buses, which has not been responsive and this has caused people to switch to private vehicles, which itself has led to traffic on the streets and There has been an increase in costs and waste of citizens' time, noise and air pollution, and an increase in fuel consumption, etc. According to the stated contents, in order to provide the best possible services to the citizens and save time and costs and to maximize the coverage of the public tra  ortation (bus) network, the placement of bus stations and the routing of inner-city buses are of special importance. The main purpose of the current research is to investigate and analyze the bus stations in the city and their proper location and routing based on the theory of the traveling salesman and the use of the genetic algorithm and the use of the SWOT technique (case example: Ilam city.( Research Methodology: This research is "applied" in terms of type and is descriptive-analytical in which library and field methods are used. In this research, first the information and data of the existing situation were examined, then Cochran's formula was used to obtain the size of the statistical population, and then the questionnaire was adjusted according to 5-point Likert and the validity and reliability of the questionnaire was confirmed through Cronbach's alpha and analyzed. An exploratory factor was carried out to obtain the factors, which had three output factors, then the questionnaires were analyzed through the SWOT technique, and using this technique, the strengths, weaknesses, opportunities, and threats were obtained and scored and weighted. The criteria for locating and routing bus stations have been achieved. Then, based on the theory of the traveling salesman, which is considered one of the NP-hard problems and is used for the vehicle routing problem, and while being the most difficult problem, it gives us the best answer, meta-heuristic algorithms have been used to solve it on a large scale. The genetic algorithm, which has a lower percentage of errors and has a better response, has been selected, and the appropriate routing of the bus stations in the city of Ilam has been done. Findings: The findings of this research showed that according to the exploratory factor analysis, there are three factors, and the findings showed that according to the SWOT technique, the inner city bus system of Ilam city has many weaknesses and threats, and the most important criteria that people have stated is that the stations Ilam's intra-city buses are not located in a suitable place and do not cover the entire city and routes, and the access of all people to the bus is not possible, and the routes on which the bus travels are not optimal and have maximum coverage. The waiting time of people is very long and the routes do not go back and forth at the same time and the number of buses is very few. Then the location of the stations was done, which was added to the number of existing stations, and finally based on the traveling salesman theory and new routing genetic algorithm, the number of buses was increased.

Road accidents are considered as one of the most influential road hazards that have a direct and significant relationship with economy, culture and politics in any society. Road accidents in suburban roads depend on various factors, and accident reports and analyzes show the occurrence of severe accidents in two-lane roads, which, in addition to the severity of accidents, the number of accidents in such roads has been on the rise due to the increase in traffic. It is that this issue has been more tangible in mountainous and border areas. Therefore, considering the importance of accidents, the use of innovative and intelligent methods in the analysis of accidents can be the missing link in planning and paying attention to it in the studies of road construction and social culture for the benefit of each region. In this research, for prediction and 0.1526 and Kappa = 0.9093 for periodic decision tree algorithm, which was respectively the lowest error and the highest value among other used algorithms  

Abstract Research Aim: Floods cause extreme and irretrievable human and economic loss. Estimating flow of floods leads to designing hydraulic structures in order to prevent flooding. The aim of this thesis is to find a formula to predict the flow of floods using physiological parameters in ungagged stations. Research method: In this research at first the most important and effective factors to estimate peak flow would be investigated. Then the parameters would be probed through Exploratory factor analysis technique and the most sufficient ones would be chosen. In order to increase the accuracy of this investment, dimensionless parameters were used. Afterwards regression analysis relates a dependent variable, which is discharge, to explanatory variables and generates equations for estimating the peak flow. To achieve more complicated and more accurate formula and also increase coefficient of determination utilizing genetic programming algorithm is helpful. Findings: The most important factors to affect floods through some recurrence intervals included 2, 5, 10, 25, 50 and 100 years were examined and some formulas were presented as a way to predict peak flow. Conclusion: Efficacious factors in estimating peak flow are drainage area, storage, lake area, annual runoff and slope of watershed. Implementing dimensional analysis and genetic algorithm gives some equations to predict peak flow which the coefficient of determination is more than using regression. Keywords: Peak flow, Regression, Non-dimensional parameters, Factor analysis, Genetic Programming هدف از اين پژوهش پيش بيني دبي پيك در مناطق فاقد داده‌هاي آماري با استفاده از پارامترهاي بدون بعد مي¬باشد.

As the first need of human life, water is the most important element in nature and has always occupied human thought. The control and optimal use of water has been a manifestation of civilization since the distant past. The creation of old dams and dams and bridges in our country shows the importance of this issue in the country. Rivers are the main source of water for humans and other creatures. In order to control the water resulting from rainfall on the banks of the rivers, especially in the lower regions of the country, he created canals to transfer water to different agricultural, urban and rural areas for industrial, drinking and agricultural purposes. Keep in mind that this itself causes water wastage and land pollution around the canal, to prevent water wastage and land pollution adjacent to the earthen canals, the covering of the canals should be considered, which in this case should be considered. be placed Both economically and in terms of water wastage. From the point of view of the ruling regime, he paid attention to the current. For this purpose, it is possible to mention the application of modeling of hydraulic structures in water transmission channels with the help of HEC-RAS software.   

Purpose: Tailings dams that are built in mines and processing plants are hydraulic structures for collecting and storing waste materials in the form of effluents and waste materials from the concentration process in processing plants and minerals. The discharge of sewage and waste materials stored in the dam due to the leakage or failure of the dam creates an important environmental environment in the region, and its entry into surface water, underground and soil causes irreparable damage to the environment and human life. . comes with Due to the inefficiency of tailings dams, less attention is paid to their proper design and construction, which breaks 2.5 times more than water dams. Waste materials in dams may have a longitudinal slope or both longitudinal and transverse slopes. In this project, an attempt has been made to investigate the effects of the longitudinal slope and the combined lateral and longitudinal slope of the bed on the volume of output material and the shape of the eroded bed. Methodology: Due to the fact that the way waste material is placed in the reservoir of the dam may have an effect on the appearance of the eroded bed and the volume of material removed due to failure. A laboratory study should be done in this case. In this research, in order to investigate the effect of longitudinal slope and combined lateral and longitudinal slope of the bed on the volume of output material and the shape of the eroded bed at the end of the experiment, scans of the topography of the eroded bed were prepared. According to bed topography scans, the volume of output material and the shape of scour hole have been investigated. Findings: When the slope of the bed in tailings is only a longitudinal slope, the volume of removed material has decreased by 8.3% compared to the largest volume of material removed in the case of both longitudinal and transverse slope. Also, the development of the eroded cavity along the width of the reservoir or the dam body during the longitudinal slope of the tailings material is about 12 times the width of the failure. While this amount is about 5 to 6 times in both longitudinal and transverse slopes. Result: When tailings have only a longitudinal slope, the development of the scour hole is across the reservoir or the main body of the dam. When the tailings have a slope of both length and width, the development of the shale hole is along the length of the tank, and there is no significant change in the volume of the external material due to the failure of the bed slope change.   

   As one of the most basic urban infrastructures, water distribution networks are very important for human society, especially in Iran, and considering the water supply in the country in the past few years, it needs to design basic networks. Economy is needed in the country. Therefore, the improvement of water distribution networks is not a step towards the management of water resources and also the basic design of water distribution networks. So that the optimization takes into account economic limitations and water resources and maintenance of the network, etc. Since one of the important factors in the control and management of the network is the application of optimal pressure in the network, and it is also another factor for planning the economic plan or reducing the costs of construction and maintenance of water networks, in this thesis, locating the optimal position of pressure relief valves in the network as a supplier The goal has been to reduce the costs in the network, and the pressure is another goal, taking into account the provision of the desired pressure. Also, the NSDE multi-objective algorithm is used as an optimization model in this research, and the commercial and free EPANET software is used for the hydraulic simulation of the water distribution network. A case study in this research is for Khorramshahr water distribution network. In this research, it has been shown that after the implementation of the model, the results obtained in the improved model are completely superior to the current state, that is, the state without valve breaker. So that for one pressure relief valve, the pressure is 8.616% and for 2 pressure relief valves, this amount of pressure reduction is equal to 39.64%. 39.642% pressure reduction in three pressure relief valves in Khorramshahr water distribution network, 39.839% pressure reduction in 4 pressure relief valves, 55.262% pressure reduction in the network and for 6 and 7 pressure valves a pressure reduction equivalent to 55.287 and 55.456 It was very useful and practical to consider the scenario of firefighting in the network to evaluate the target. On the other hand, it can be said that adjusting the pressure relief valve in accordance with the positions and output options of the proposed models is a significant improvement in the issues, i.e. the pressure is in the desired range and the costs are reduced.

Research Aim: Tailings dams play a critical role in the mining industry, responsible for safely collecting and disposing of tailings while also conserving water and protecting the environment. However, the practice of constructing these structures using the tailings themselves, coupled with inadequate design and supervision, has resulted in a high number of tailings dam failures. This research aims to investigate the potential impact of tailings dam failures in terms of tailings output. The goal is to use this information to prevent future losses and protect against the negative consequences of tailings dam failures. Research method: This research focuses on the specific scenario of tailings dam failure near the support, where a nearby pond is present and the tailings are not prone to liquefaction. In order to conduct a thorough investigation, a large-scale pond was used to ensure that the results are not influenced by the dimensions of the dam reservoir. Additionally, a valve was incorporated into the laboratory model to simulate local failure scenarios. The tests were carried out at varying water levels and repeated three times to ensure the validity of the results. Findings: In this research, the bed erosion pattern and sediment transfer rate were studied in relation to the impact of increasing water levels in the tailings dam reservoir during a local failure near the abutment. Conclusion: The results of the study indicate that over time, as water and sediment are released from the dam reservoir, a pit forms in the sedimentary bed. This pit eventually develops into a submerged hydraulic jump. Additionally, it was observed that the length of the scour hole along the direction of the dam body is roughly twice that of the scour hole's length in the direction perpendicular to the dam body.   

Tailings dams are structures builtto store waste from mining operations as well as mineral extraction operationsfrom ore. Tailings dams are completed over time and raised according to thevolume of tailings produced. The purpose of building these structures is tostore waste materials in order to prevent environmental pollution. In thisresearch, the amount of mineral tailings transferred due to a local gap farfrom the support in tailings dams with water in the reservoir is investigatedin a laboratory manner. It should be noted that three different water levelswere considered in this study. In order to validate the failure of the dam was repeatedthree times in each water level. According to the laboratory results, it wasobserved that three types of flow patterns can be seen in these failures. Thedimensions of the scour hole caused by the failure of the dam in the directionof the failure are 2 to 5 times that of the direction perpendicular to thefailure. It also found that with the increase of the water level, the volume ofthe discharging materials increases.

The stability of seismic earth dams is particularly critical to the integrity of downstream areas. This thesis describes a numerical study related to both the seismic response and the analysis of earth dams using the finite element method. In this thesis, we will study the effect of the hydrodynamic stresses of an upstream reservoir on the elastic seismic response of dams. A methodology will be proposed in which the reservoir field is modeled with a particular focus on the accurate prediction of the hydrodynamic pressures on the upper dam face. The main part of the thesis is related to the study of the design of the Shehabi dam under study and their hydrological and historical seismic data, which will be analyzed in order to validate the numerical model and get a good agreement between the recorded and projected data. Obtaining dam response during an earthquake with different acceleration and duration using Geo-Studio Seep/w and Quake/w software. Subsequently, using as a reference the calibrated model, parametric studies are performed in order to obtain a better insight into the dynamic response and analysis of the response of the embankment of the dam under consideration during an earthquake with different acceleration, duration and water reservoir level. It is better that we will conduct a three-dimensional seismic analysis of the Shehabi dam by adopting the initial values of the shear stiffness. This will enable insight into the effects of the dam-valley interaction it will confirm whether the \\amount" of stiffening adopted in this study is appropriate.

باكاهش منابعآب قابل مصرف و تنش آبي رو به افزايش درساير نقاط جهان ، توسعه روش‌هاي مختلف  جهت مديريت كارآمد اين ماده حياتي، اهميت ويژه‌اي پيدا كرده است. كاهش حجم آب به حساب نيامده از مهمترين روش‌هاي مديريت مصرف آب محسوب مي‌شود. نشت كه به عنوان اصلي‌ترين موئلفه آب به حساب نيامده شناخته شده است،   نه تنها يك مساله اقتصادي، بلكه مساله‌اي زيست ‌محيطي و به طور بالقوه يك مساله بهداشتي و ايمني مي‌باشد كه كاهش ميزان آن در سيستم‌هاي آب‌رساني را مي‌توان يكي از اهداف عمده سازمانهاي تأمين و توزيع آب به‌ شمار آورد. در تحقيق حاظر از يك تكنيك هوش مصنوعي تحت عنوان ماشين يادگيري افراطي (ELM) جهت يافتن محل و ميزان نشت در شبكه توزيع آب استفاده شده كه با توسعه اين روش برخي از   محدوديت‌هاي استفاده از تكنيك‌هاي هوش مصنوعي منجمله تعداد خروجي مدل‌هاي‌ يادگيري ماشيني رفع شده و همچنين فرآيند اجرا كه در اكثر اين تكنيك‌ها در مواجه با داده‌هاي با ابعاد بزرگ امري نسبتا زمان‌بر است در مدل   ELM بكار رفته كاهش يافته است. در اين تحقيق همچنين از يك مدل شبكه عصبي پرسپترون چند لايه MLP جهت مقايسه نتايج و عملكرد آن با مدل ELM   استفاده شده است. روش‌ها بر روي يك شبكه توزيع   آب فرضي و كاملا حلقوي موسوم به شبكه توزيع آب پولاكيس اعمال شدند. نتايج بدست آمده نشان مي‌دهد روش بكار رفته كه در آن ماهيت وابسته به فشار نشت حفظ شده است، با حداقل برداشت اطلاعات هيدروليكي از نوع فشار گرهي، علاوه بر شناسايي موقعيت گره‌هاي نشت‌دار، محل و ميزان نشت گرهي كه نشت كمتري را دارد با دقت بالايي پيش‌بيني كند.  

Normal 0 false false false EN-US X-NONE FA استفاده از اطلاعات ماهواره‌اي جهاني ، در دسترس و ارزان‌تر در اندازه گيري ويژگي‌هاي رودخانه‌ها ، كه به‌عنوان جايگزيني براي اندازه گيري‌هاي در محل و گران قيمت مورد استفاده قرار مي‌گيرد. با استفاده از داده‌ها و اطلاعات ماهواره‌اي مطالعات نشان داده است كه مي‌توان دبي رودخانه‌ها را به‌طور دقيق كاليبره كرد. دو روش جديد از توسعه زنجيره‌هاي ماركوف (MC) ، يعني روش‌هاي آنلاين-زنجيره‌هاي ماركوف (O-MC) و زنجيره‌هاي پيشرفته آنلاين ماركوف (EO-MC) در مطالعه حاضر براي افزايش عملكرد پيش بيني MC معرفي شدند. مزاياي روش O-MC نسبت به MC از پياده سازي آنلاين حالت‌هاي صحيح و EO-MC   نسبت به MC مزاياي اجراي هم‌زمان آنلاين حالت‌هاي صحيح و ماتريس ماركوف (MM) به‌روز شده در طي داده‌هاي آموزش است. اين روش‌ها براي پيش بيني سيگنال‌هاي ماهواره‌اي كوتاه مدت رودخانه mohave استفاده شد. در مرحله بعد ، به‌منظور اندازه گيري قابليت اطمينان محاسبات ، تحليل عدم قطعيت مونت‌كارلو براي هر سه روش مبتني بر MC در نظر گرفته شد. براي انجام اين كار ، هر مدل 1000 بار توسعه داده مي‌شود و دو شاخص 95 درصد عدم قطعيت‌هاي پيش بيني شده (95PPU) و ضريب فاصله متوسط (d-factor ) محاسبه مي‌شود. عملكردهاي MC و دو پسوند آن يعني   O-MC و EO-MC نيز در موارد عدم وجود اطلاعات آموزشي مورد بررسي قرار گرفت. براي انجام اين كار، درصد آموزش كل مجموعه داده‌ها از ?? درصد به ? درصد به‌تدريج كاهش‌يافته و عملكرد مدل‌ها در توليد سيگنال‌هاي دقيق آينده در مجموعه داده‌هاي مشاهده‌شده محاسبه مي‌شود.در آخرين مرحله از اين مطالعه، مشكل ورودي متغير ورودي (IVI)براي روش‌هاي مبتني بر MC در نظر گرفته شد و نتايج با رگرسيون خطي، Perceptron Multi (LR)، ماشين يادگيري افراطي (elm)، و روش‌هاي رگرسيون توابع پايه شعاعي (RBF)مقايسه شدند. نتايج نشان داد كه عملكرد EO-MC و O-MC بسيار بهتر از روش MC ساده است. علاوه بر اين ، مي‌توان نتيجه گرفت كه EO-MC و O-MC تقريباً در تحليل عدم قطعيت عملكرد يكساني دارند و هر دو آن‌ها قابل اعتماد و قوي هستند. مزيت اصلي EO-MC در مقايسه با روش O-MC هنگامي ارائه مي‌شود كه عملكرد مدل‌ها در شرايطي مقايسه شود كه تعداد نمونه آموزش بسيار كم باشد. در نهايت ، با توجه به مشكل IVI ، نشان داده مي‌شود كه عملكرد O-MC و EO-MC به‌طور قابل توجهي بهتر از روش‌هاي LR ، MLP ، ELM و RBF است. كليدواژه: داده‌هاي دبي ماهواره‌اي ، دبي روزانه، درياچه موهاو، زنجيره ماركوف، الگوريتم مونت‌كارلو.  

   Hydraulic jump is one of the complex issues of hydraulic science. It is also very important to reduce the energy downstream of hydraulic structures, for which the supercritical current upstream must be converted to the subcritical current downstream. To reduce energy, a phenomenon called hydraulic jump occurs, which is associated with excessive energy consumption. In general, hydraulic jump is divided into two categories: free and submerged. Whenever the downstream water jumps are greater than the secondary depth, the hydraulic jump occurs submerged. This study was conducted to numerically study the three-dimensional vortex flow in the case of a severely submerged hydraulic jump in the case of a sudden opening downstream. In the present study, the question is what part of the channel width should be where the energy dissipation occurs in the submerged hydraulic jump, so by moving the sudden opening from the center of the channel to other coordinates of the channel width and examining the effective parameters in Hydraulic jumps such as horizontal velocity profiles, vertical velocity profiles, pressure, energy dissipation and viscosity by cross-section in the channel have investigated the effect of this displacement on the energy dissipation of hydraulic jumps. In order to numerically study the submerged hydraulic jump, a three-dimensional code developed by (Mahmoudi Nia et al,1391). In accordance with the laboratory model of Zari and Badour (2007) was used. In the next step, numerical modeling validation is performed with laboratory results, and then the parameters that are not addressed in the article Zari and Badour (2007) are studied, and finally by changing the sudden opening from the center of the channel to other coordinates, the rate of change It has been evaluated in hydraulic jump performance. In general, after examining the effective parameters in submersible hydraulic jump and flow patterns, it was concluded that if there is a sudden opening in the center of the channel, due to its centrality and distance from the walls, vortices appear at the beginning of the jump and then at the end. We saw a slow flow pattern jump, but when a sudden opening is located near the walls, we will not see a slow flow pattern due to the impact of the flow pattern hitting the wall and the resulting vortex at the end of the jump.                Keyword: Numerical Simulation, submerged Hydraulic Jump, Vortex Flow, Turbulence Profile, 3D Flow Pattern

The aim of this study was to evaluate the shear stress distribution on the bed of a trapezoidal channel, which is one of the most widely used open duct channels. The flow structure in open ducts is directly affected by how the shear stress is distributed in a humid environment. The equilibrium of uniform currents is due to the shear stress on the wet environment of the channel and in the direction of the flow path. On the other hand, the non-uniform distribution of this stress on the bed and the wall of open ducts causes corrosion of the bed at one point and sedimentation at other points. In this study, laboratory data from a highly accurate article by Tominaga et al. Were used as an indicator for validating a computer model developed with Flow3D software, which obtained a correlation coefficient of 0.92 between the values The laboratory confirmed the accuracy of the numerical model by plotting the shear stress values ??of the channel bed resulting from the software implementation. In the next step, trapezoidal channels with different geometric dimensions were analyzed and for 88 different states, shear stress distribution, flow pattern, velocity field, fluid level, and secondary flow pattern were examined and plotted based on geometric characteristics. Dimensional cross-section and shear stress, the effect of channel dimensions on shear stress distribution were investigated. Responses showed that dimensionless shear stress has a limited range, and the shear stress distribution follows a relatively constant pattern. Finally, certain diagrams and tables were obtained for hydraulic designers to achieve the correct understanding and amount of shear stress and its distribution in the trapezoidal channel bed under similar conditions, by spending the least amount of time.  

  Assessing thephenomenon of climate change and its possible consequences on the hydrologicalprocesses of the basin will greatly contribute to the challenges of managersand planners of water resources in future periods. The effect of climate changeis investigated by simulating hydrological processes with a physical model ofrunoff precipitation. Hydrological models provide a framework for examining therelationship between meteorology and water resources. The purpose of this studyis to investigate surface runoff using climate change models and SWAT model. Inthis study, the runoff in Pol-e-Shah hydrometric station was first investigatedand using the swat cup software, the statistics of the relevant hydrometricstation and using the sufi2 optimization algorithm, the parameters affectingthe flow and flow rate were calibrated and extracted. Correlation andNash-Sutcliffe values 0.75 and 0.79 were extracted for calibration interval and0.71 and 0.61 for validation. Then, in order to study the statistical indicesof rainfall and temperature under the influence of climate change using larsWG6software and using hadgem and miroc5 climate models under diffusion scenariosof 2.6, 4.5 and 8.5, exponential microscale action and extraction ofprecipitation and temperature data for statistical length 2020 to 2080.Finally, in order to obtain the effect of climate change on runoff, swatsoftware was implemented under each of the scenarios of climate models inrelation to the statistical length of different periods and the diagramsobtained from model runoff changes to simulate runoff discharge on averagemonthly with Climate data were compared and showed a decrease and increase inrunoff in some months of the year.keywords: Runoff - SWAT - lars WG6- Climate change – Pol-ShahBasin- - Climate models - HADGEM2 and MIROC5

Abstract Objective: Compound channels are the hydraulic cross section of rivers. The entry of municipal, industrial and agricultural wastewater, industrial waste, thermal pollution and nuclear power plants as a stream with different densities into the riverbed is a very important issue and has a great impact on human life and the environment. Investigating how this dense stream propagates through the compound channel helps control pollution in riverbeds and preserve the environment. Research Methodology: In this research, in order to simulate the density flow in a compound channel based on Navier-Stokes equations, the Reynolds stress turbulence model (RSM) has been performed using the open-source software OpenFoam. Assuming a density difference The gap between the two fluids is considered to be Bozinsk. Compound channels with shallow, medium and deep floodplains as well as narrow, medium and wide floodplain have been studied. Results: The accuracy of the model in simulating the experimental model of the initial velocity flow in the compound channel and the dense flow in the rectangular channel is shown. Numerical model is capable of simulating experimental models and the results are in good agreement. Conclusion: Numerical simulation of dense flow with compound channel with different depth and width of floodplain has been done. Studies show that floodplains with greater width and depth have more participation in flow transmission and with increasing depth and width of plain floods, more instability is seen in plain floods. It is low. Also, in a wide floodplain, the dense flow behaves similarly to the main channel.   

Abstract: Today, the use of satellite imagery in predicting flow rate In situs stations is of considerable importance. In the present study, a new technique based on artificial intelligence models for predicting satellite signals (S) is presented, which with the introduction of a new indicator called PS, the problem of imitation of input data is greatly solved. Accordingly, a multilayer perceptron (MLP) model in combination with the two-objective evolutionary optimization algorithm (NSGA-II) for predicting S data is introduced and the proposed model in the present study is named IM. Also in the present paper, the actual values ??of the flow rate at local stations of different rivers are calculated by the soil moisture model and compared with the flow rate values ??obtained from satellite signals. Simultaneous decrease of MSE and PS indices in the proposed IM model has been the subject of the present study, which has been neglected in conventional OM methods in predicting time series. In addition, a typical MLP model is presented in the research to evaluate and compare IM performance. Forecasts have been made for six rivers: White, Red, Missouri, Connecticut, Willamette, and PeeDee. Keyword: Satellite signals, River discharge, Multi-objective optimization, Flood forecasting, Soil moisture method  

Abstract In this research, the groundwater level was predicted using GRACE satellite pair and the time series model obtained by this satellite was used using GSGMDH neural network model. The study area of ??this research is the catchment area of ??Lake Urmia located in northwestern Iran. For this purpose, 163 months of GRACE satellite data were used during the years April 2002 to June 2017. To remove the hydrological parameters of GRACE data, the GLDAS hydrological model was used. The output of the satellites includes 6 points located in the selected basin, the results of which show a decreasing trend of groundwater equivalent thickness with a range of changes of -50 to +50 mm for six specific study points in the basin. The satellite results for six study points of Urmia Basin were compared by observing the information of piezometric wells in the area of ??each point. In order to accurately compare the water level, the observation wells were converted to water-equivalent thickness using a special discharge coefficient. Comparing the output of GRACE satellites with observational values ??showed that the value of correlation coefficient in six points is 0.48 on average, which is consistent with the results of similar studies. Also, the values ??of RMSE, MARE and RMSRE are equal to 8.8 on average. It is 1.4 and 1/3, which indicates the proper performance of GRACE satellites in estimating the equivalent thickness of groundwater in the study area. Then, using the GSGMDH model, the time series obtained by GRACE satellites were modeled for six study points. To do this, after removing the trend in the data using ACF diagrams, the delays with the highest autocorrelation were identified and used in the modeling process. Due to the uniformity of the data trend in the six points, the data were modeled together for all points. The results show the appropriate performance of the model so that the correlation coefficient in the training stage is equal to 0.96, which is 86 for the experimental stage. / 0 has been reached. The value of RMSE in the training and testing phase was very close to each other, but the value of MARE in the experimental phase gave better results. Keywords: GRACE satellites, Urmia catchment, GSGMDH model time series, GLDAS hydrological model, groundwater equivalent thickness, piezometric well information.   

  Wastewater treatment plants are among the most important urban facilities, the quality parameters of inlet effluent to the treatment plant to determine the load of inlet pollution to the facility and the selection of the appropriate treatment system and the quality parameters of the outlet effluent. Ensuring environmental constraints and investigating the potential for reuse of wastewater must be constantly monitored and evaluated. Since systematic measurement of these indices is subject to limitations, providing highly accurate software sensors and acceptable generalization power for predicting qualitative indices is crucial. As a result, in recent decades, extensive studies have been done on the modeling and prediction of the aforementioned indicators and increasing the accuracy of existing methods. On the other hand, there is no research that investigates the role and performance of hybrid models in predicting qualitative parameters of effluent, comparing the accuracy of linear, nonlinear and hybrid models, investigating the effect of different pre-processing approaches on modeling accuracy, investigating the effect of pre-order. The processing and role of outliers in the accuracy of time series models is felt. Therefore, for the first time, the present study will examine these cases.

This thesis presents a novel method for thedevelopment of an optimal water supply plan showcased using data from the Gamasiab basin, located in Kermanshah province, Iran, concerning new dams that are being constructed in this semi-arid region. In this research, a new group multi-criteria decision-making [MCDM] plan is proposed by combining two MCDM methods based on the Fuzzy Delphi and Fuzzy ELECTRE III methods that convert the experts’ opinions to triangular fuzzy numbers TFNs] based on the level of uncertainty associated with various quantitative] and qualitative criteria. Considering the opinions of non-stakeholders and data analysis using the Fuzzy Delphi method, the criteria were evaluated. Then, by analyzing the results using the Fuzzy ELECTRE III method, the final ranking of scenarios is obtained. A sensitivity analysis was conducted to assess the effect of uncertainty on the performance of the decision-making [DM] system in scenarios ranking. To calculate the importance weight of criteria, Expert choice software and empirical method were used. In addition, a hierarchical model based geographic information system [GIS] and Analytic Hierarchy Process [AHP] was used to determine the importance weight of quantitative criteria. Then, by comparing the result of GIS-based model with the quantitative criteria weight obtained from two other ones, it was found the importance weight of the criteria in the GIS-based hierarchical model due to the high ability to store and integrate information layers, has a higher value. Furthermore, the total expense criteria, the environmental impacts, transmission and water diversion, and geographical conditions of the region played significant role in selecting the optimal scenario. Additionally, the result of a WEAP model was used to evaluate the performance of the optimal scenario in terms of hydrological parameters. The data indicated that there was a good agreement between the results obtained from the hydrological model and the scenario ranking by employed method. Altogether, comparison of the proposed method with other MCDM methods, including Fuzzy AHP and .Fuzzy TOPSIS, indicated that the results of the employed method matched more closely to the local experts’ opinion. Keywords: Optimal Water supply, Gamasiab basin, Group Decision-Making, Fuzzy Delphi, Fuzzy ELECTRE III, Triangular fuzzy number, GIS

  Abstract  ources of fresh water are limited. In high-resource countries with rich resources and highly developed technical infrastructure, there are many ways to protect, recycle and reuse it. In many other areas, however, the availability of water for further development is higher than the satisfactory level, and it is essential for the rapid growth of the population to survive even existing communities or to meet the ever-growing demand. In these areas, humans can not be dumped from the dams and water reservoirs exploiting water resources.The study and interpretation of precise instrument data is one of the most important dams monitoring and safety assessment processes during the operation period of the dam. In spite of the great importance of these equipment, the data obtained during the operation of the dam, little attention has been paid to this category, and few studies are available in this area.In addition to designing and implementing them, the most important challenges in development projects are safety and stability of various components throughout the building. To achieve this, in all large dams, installing necessary tools for pore volumes, soil pressures and changes The shapes are measured during the three years of construction, the first dewatering and the operating time, and the performance of the dam is evaluated and analyzed. In this thesis, the results of the designed tool in Jamishan Dam were evaluated and the structural performance and stability were evaluated. For the instrument installed in different parts of the dam body, FLAC software was used to determine the numerical model.The behavioral models used in the analysis are linear elastic model and elastic-plastic elastic model of Moore-Coulomb. In order to make the model more realistic, the step-by-step technique of the dam layers has been considered. Horizontal and vertical displacement, vertical stress and cavity water pressure were interpreted and the results showed the correctness of the Jamyshan dam performance and the elements of the sealant. Also, the results of modeling and instrumentation suggest that its dam is in a stable and safe condition.  Comprehensive review of dam failures in dams, different causes of soil dams destruction and recognition of leak phenomena as the main causes of soil dams destruction are other important parts of this research.

  Abstract Investigating and studying the flow characteristics at the confluence of the rivers has been one of the topics discussed in the last decade, where the region is known as the one with high turbulence and three-dimensional motion. Due to changes in the amount and direction of velocity, flow rate and sediment discharge, phenomena such as bed erosion and bank erosion occur. The sepration zone immediately forms a junction down stream and causes flow contraction. which this leads to an increase in velocity and thus to bed erosion. In addition, the resulting vortex flow creates problems for shipping. Therefore, numerous field and laboratory studies have been done to investigate the pattern of flow and sediment conditions at the confluence. These studies have investigated the effects of various parameters such as the discharge ratio, Froude number, and the angle of junction on the hydraulic conditions of the flow. However, no significant studies have been done to reduce the velocity and decrease the dimensions of the separation zone at the open channels junction. The present study aims at investigating the effect of nonsubmerged guide walls on the separation region and velocity variations. Firstly, a numerical model was written utilizing the flow3d software, which, according to the previous studies, was verified. Then, the effects of the guide walls on the junction flow pattern were investigated. In addition, the effect of the guide walls on decreasing dimensions or removing the separation zone as well as the velocity reduction at the open channel junctio   were investigated. The results showed that the application of the guide wall decreases the velocity at the open channel junction. Also, in models where the wall was spaced b/2 (b is the width of channels) from the inner wall of the main channel, the separation zone was not omitted, but its length was reduced. And in models with wall b/4 spaced from the inner wall of the main channel, the separation zone was removed.

development of hydrologic models for flow routing in multiple-branches systems

Climate change and increased harvesting of water resources cause environmental problems and major changes in lakes and wetlands. In recent years, this has caused many lakes to face a complete drought. The Bakhtegan and Tash Lakes is one of the most important environmental assets and the second largest lake in the country is almost dried up. In this study, to determine the process of drying the lake, using the LandSat satellite images and image processing by ILWIS and ArcMap software, the time series of water surface of the Bakhtegan Lake were prepared monthly for a thirty year period. Then, the equation was extracted between the annual average area of the lake and the annual discharge of the Khor River at the site of the Paul Khan Hydrometric Station. According to the fifth report (AR5) of the IPCC, in order to assess the effects of climate change the Outputs of the General Climate Model (GCM) on the three the sub catchment of Droudezan, Sivand and Hasanabad (Korr), have been downscaled. Among the selected models, after review, the BCC-CSM 1.1 model was used as the preferred model in each of the three sub catchment for downscaling in order to produce more appropriate results. The results of downscaling in accordance AR5 in the form of the average of four scenarios indicate a decline in precipitation by 2050 compared to the long-term average for the Droodzene sub catchment of 23 mm, Sivand   ub catchment 12-mm and Hassan Abad (Khor) sub catchment is 10 mm. During this period, the average long-term temperature is increased for the Droudezn sub catchment is 1.05 degrees Celsius, Sivand sub catchment 1.06 degrees Celsius and Hassan Abad 0.6 degrees Celsius. In order to apply the effects of climate change on the amount of runoff entering the lake, the water resource planning model of Bakhtegan watershed was created and calibrated in WEAP software. By modifying the discharge, for conformed to the climate change conditions (rainfall reduction), predicted the annual forecast of the runoff Khor River in the Pul Khan site by 2050, and finally, using the governing equation between the annual average area of the lake and the annual yield of the Khor River, The area of the lake in the period from 2020 to 2050 is projected to be annual average. By the year 2050, the average annual of the lake will be 20% of the past area. The largest predicted area of the lake is related to the Rcp60 scenario in 2038 with a value of 568 square kilometers (equivalent to 40 percent of the lake area), and the least is the Rcp85 scenario in 2038 with a value of 77 square kilometers (equivalent to 7 percent of the lake area).Water resources management is very important in preventing environmental crises and losing national resources. Climate change or any other risk can be controlled by correct recognition of the phenomenon, and short-term and long-term planning, control adverse consequences and minimize losses. The results of this research can be used to manage and plan water resources in the Bakhtegan Basin, in allocating the water necessary to maintain the Lake Bakhtegan and Tashk as a national capital.

  Pipelines are one of the most important engineering structures and systems. These systems are very significant from the economic and strategic point of views, and are widely used all over the world. Therefore, they must be investigated more accurately. Since the length of the pipelines is very long and may exceed several hundred kilometers, a more precise study of the flow patterns such as velocity, pressure, friction as well as feasible deformation may lead to a more economical and accurate design of mentioned systems. Although investigation of the related equations is complicated, costly, and time consuming, these difficulties may be overcome using engineering software. In this article, a robust analytical software of fluid mechanics Ansis Fluent 15 is employed to verify validity and accuracy of turbulence models k-omega, k-epsilon, and Reynolds stress. The results obtained in this study have good agreement with those reported in the literature.

  در تونل هاي آبگيري سدها از دريچه هايي با مدخل ورودي بيضي گون جهت كاهش افت و احتمال وقوع كاويتاسيون استفاده مي شود اين دريچه به وسيله شبكه آشغالگيري كه در ابتداي دهانه نصب مي گردد جهت جلوگيري از ورود آشغال هاي بزرگ كه امكان آسيب رساندن به سيستم انتقال از جمله دريچه ها، شيرها و توربين را دارد محافظت شود. طراحي مدخل و شبكه آشغالگير مناسب نيازمند شناخت جريان در اطراف شبكه آشغالگير و اطراف مدخل بيضي گون مي باشد، همچنين ضروري است بررسي گردد كه شبكه آشغالگير و دريچه آبگيري   بر مشخصات جريان تا چه طولي از تونل، پنستاك، دريچه ها و خروجي تونل تاثيرگذار بوده و مقدار اين اثرگذاري در طرح بهينه اقتصادي، ايمني و عمر سازه مورد بررسي قرارگيرد. در اين پژوهش به بررسي مقدار اثر تغيير دماي جريان و مقدار هواي سيال در جريان دوفازي ماندگار و دائمي در حالت هاي مختلف بازشدگي دريچه كشويي به عنوان پارامترهاي متغير سيال پرداخته شد كه نتايج آن نشان داد كه اثر تغيير دما و غلظت هوا برفشار جريان اثري بسيار جزئي و بر خصوصيات سرعت اثري تقريبا جزئي دارد. اثر تغيير زبري ديواره ميله هاي شبكه آشغالگير، ديواره تونل، تغيير قطر ميله هاي شبكه آشغالگير، اثر انسداد شبكه آشغالگير به وسيله تنه هاي درخت و تغيير شرايط ورودي و خروجي سرعت و فشار جريان در     بازشدگي هاي مختلف دريچه كشويي از پارامترهاي مهم به عنوان پارامترهاي متغير مقادير اوليه و شرايط مرزي است كه تحليل شدند. مي توان نتيجه گرفت اثر تغييرات جزئي در شرايط مرزي و مقادير اوليه بسيار بيشتر از اثر تغييرات قابل ملاحظه ي محدود در مشخصات سيال خواهد بود. از نتايج ديگر اين پژوهش مي توان به تحليل رفتار سه بعدي جريان در اطراف     ميله هاي شبكه آشغالگير و دريچه كشويي اشاره كرد كه در حالت انسداد يا بسته بودن بيش از يك حد مشخص ( سرعت و فشار اعمالي) موجب پس زدن جريان، آشفتگي ها و نوسانات شديد و در بعضي حالات عدم پايداري و همگرايي معادلات خواهد گشت.

بررسي عددي روش هاي مختلف استهلاك انرژي جريان پايين دست شيب شكن هاي واقع در كانال هاي باز

  AbstractIn this research, we study the effects of climate change on climatic variables of precipitation and temperature in the upcoming period and the effect of predicted changes on Chaghchmal plain groundwater levels in the next two 20-year periods. For this purpose and in order to simulate the aquifer, the GMS subterranean water model has been used. During the calibration period for the 18 month period (March 2009 to September 2008), the error rates for the two Mangram and non-stable models are MEX and MAE respectively. Also, verification The model was also carried out during the 18 month period (September 2011- April 2010) and the amount of RMSE and MAE indicators were obtained respectively. Also, to study the effect of climate change on the fluctuations of groundwater level of the region in the upcoming period, six AOGCM models under three scenarios A2, A1B and B1 and two probability levels of 90 and 50%, and with regard to the uncertainty of the general circulation models, prediction of climatic variables And temperature were paid. The LARS_WG model and the proportional method were used for mapping and localization of climate parameters. The predicted climatic variables for scenarios A2, A1B and B1 and two probabilities of 90% and 50% respectively, changes for the mean long-term temperature of 0.65 +, 0.653 +, 0.653 +, -0.04 and +0.6 ° C, and the long-term average changes The precipitation was -0.15.2.06 -, + 2.25, -30.2 and -0.095 percent during the period of 2011-2030, and the same for long-term changes in temperature +2, + 2.2.1.55 +, + 0.98 and +2.3 ° C, and average long-term variations of rainfall -17, -23.7, -18.3, -46 and -13.8% during the statistical period of 2065-2046. Ultimately, fluctuations due to climate change on aquifer levels were identified under scenarios. Based on the results, groundwater level under the scenarios A2, A1B and B1 and two probabilistic levels of 90 and 50 percent for the periods 2011-2030 and 2046-2046 compared to the period 1996-2015 averaged between -1.55 to -1.83 meters Drop showed In view of these changes in order to adapt and reduce the negative effects of climate change on the region, using the proper management of water resources and taking into account all aspects of agriculture, drinking, industrial and environmental uses, the effects of climate change on the water resources of the region Castells, in order to keep these resources as good aspossible.   Key word: Groundwater balance, Climate change, AOGCM general circulation model, Climate scenarios, Uncertainty, GMS model, LARS_WG model.

بررسي عددي مشخصات جريان در امتداد سرريز جانبي، دركانال همگرا شونده

  Unbonded fibre-reinforced elastomeric isolator (U-FREI) is a relatively new seismic base isolator in which fiber layers are used as reinforcement to replace steel shims as are normally used in conventional isolators. Further, the top and bottom end steel connector plates of conventional isolators are also removed. In general, the horizontal response of U-FREI is nonlinear because of reduction in contact area due to rollover deformation and reduction in shear modulus of isolator under large deformation. Thus, evaluation of horizontal stiffness of U-FREI is a challenging problem. The unbonded application leads to rollover deformation that results in advantages such as decreasing the demand tension stress between internal layers and increasing efficiency of the bearing as a seismic isolator. Most of the previous finite element analysis studies on FREIs only have addressed the simulation of the monotonic behavior of this type of isolators. In this thesis, the main objective is to simulate the laterl load-displacement hysteresis loops of U-FREIs. The combination of an effective hyperelastic behavioral model in large deformations with viscoelastic behavior, the hyper-viscoelastic model will be produced that has the ability to consider the time dependency in the finite element analysis of isolator. The hyperelastic parameters are evaluated by curve fitting of theoretical curve to three uniaxial tension test of elastomer dumble-shaped specimens. The viscoelastic behavior is simulated using the Prony Series, and its parameters are determined by using the Nelder-Mead simplex method optimization algorithm, and the cyclic experimental results. The results show that the use of viscoelastic material model in conjunction to hyper-elastic material model leads to the effective simulation of horizontal stiffness and hysteresis load-displacement loops of FREIs. As another component of this thesis, The lateral response of isolator under various vertical compression stresses is studied using the finite element model that is developed in this study. Results show that both the effective horizontal stiffness, and equivalent viscous damping are increased by increasing vertical compression stress.

Many systems have been used for this purpose including seismic base-isolators which are among the most important ones. In this method, structures move isolated from the ground by placing a flexible lateral structure between the structure and the foundation. Isolators have several types, the most common of which are Steel Reinforced Elastomeric Bearings (SREBs). These isolators are made of intermittent and bonded  elastomer layers and reinforced steel plates. Such isolators currently lack required economic justification for many conventional structures due to high expenses. In the last fifteen years, new elastomeric isolators have been developed called Fiber Reinforced Elastomeric Bearing (FREBs). In these isolators fiber reinforced layers are used, instead of heavy metal plates, to control the lateral strains of the elastomeric layers and to provide the necessary hardness along the vertical axis. In terms of bonding to the bearing, the isolators are categorized into three groups of "bonded", "partially bonded" and "unbonded". In unbonded mode, isolators lack the upper and lower steel plates, which reduce the expense and weights of isolators. In unbonded mode, no mechanical connection is made between bearing surfaces. In this situation, shear force is transmitted through friction at contact surface of the isolator with the bearing. These detachers undergo a unique deformation under rollover lateral displacement, which leads to the contact of the initial vertical surface of isolator with the upper and lower bearing of the isolator.   Following a rollover deformation, the effective lateral hardness of the isolator has been reduced further, which means increasing the vibration isolation period and, in fact, increasing the seismic isolation efficiency. In this research, the finite element analysis has been used to model the behavior of force- one-way lateral deformation of Fiber Reinforced Elastomeric Bearing (FREBs) isolators. The modeling of these isolators is conducted in 3D format using MCS MARC finite element software. Providing a 3D model of Fiber Reinforced Elastomeric Bearing isolator with material specifications and geometric dimensional scaled with real dimensions in finite element analysis allows us to avoid some costly and time-consuming laboratory studies. The focus of this thesis is on the modeling of three-dimensional finite elemental behavior of the Fiber Reinforced Elastomeric Bearing circular isolators. Research literature in this area has nothing to say. In the analysis, the effect of the geometry of the rubber layers on horizontal and vertical responses of elastomeric isolators was studied. The effect of thickness is investigated by (

پيش بيني سيل با استفاده از تلفيق تصاوير ماهواره اي و مدل بارش-رواناب در مناطق فاقد آمار

  Nowadays, dams are one of the most important sources   of water supply in drinking, agricultural, industrial sections, energy generation and other water related activities. The development of reservoirs operating policies to meet each of the water requirements is vital. operating policies are in fact guidelines that,   specify the amount of storage, and also the waterrelease to meet needs, seasonal flood control, and other reservoir operating purposes in the intended steps. In reservoirs operating , a high percentage of system reliability is a positive factor, but in arid and semi-arid regions where the amount of discharge into the reservoir has   evere fluctuations, it is reasonable to reduce the system reliability and dercrease the amount   water allocation to the Consumption points ,to prevent the occurrence of critical conditions such as emptying the reservoir. According to the above, optimization of operating policies has become more important as demand grows, especially in dry years, taking into account hedging. Reservoir optimization models have different approaches that the modeling and their assumptions can be   determinative in reservoir operating. In models where the input data of the reservoir is the recorded river data and were assumed definitive, the results of the model are limited to historical data and should be calibrated for new input flows to the reservoir. In these models, ignoring the rules of hedging in arid and semi-arid regions can lead to severe failures in the operating of the reservoir. In this study, which was carried out on Balaroud reservoir dam located in Khuzestan province, the optimization model was based on the new PSO (parametrization-simulation-optimization) method. In this method, considering the stochastic flow conditions, the optimal reservoir ration parameters are determined through the reservoir simulator link (WEAP model) to the NSGA-II multi-objective optimization algorithm. In order to apply the stochastic flow conditions, the inflow into the reservoir ,initially 4800 synthetic monthly times series was generated for each Bootstrap, Thomas and Fiering, Fragment and Valencia-Schaake methods. Then the statistical parameters of the produced series of each method were compared with the historical river series. The results showed that the Fragment method was better than other methods, and the series produced by this method were used to apply the stochastic conditions in the PSO model. In the model, 4800 months for calibration and 372 months for the validation of the model are included. At the end, the results of the PSO model were compared with the results of the standard operating policy (SOP). The results show that the proposed model has been able to manage the allocation in needs of dry months and prevent the reservoir from emptying.

بررسي تاثير پيش پردازش داده هاي هيدرولوژيكي بر نتايج انواع مدل هاي   پيش بيني سري هاي زماني   هيدرولوژيكي

  Open channels from the past are the most effective and optimal sections used in water transmission systems. Among the various methods of water transfer, the use of gravity and the movement of water in a free-flow flow, along with the construction of appropriate canals and hydraulic structures, such as valleys and overflows, are the most commonly used methods for watering and irrigation. Considering channel characteristics, including type, gender, as well as the geometric shape of the channel section, is essential. The most important axis is the design of water channels, the transfer of water from the place of extraction to consumption, with the least losses and the lowest cost of exploitation, which the issues above have made the experts persuaded to revise the design and construction of water channels in scientific circles. This has led to studies on floor coverings and channel walls, manning roughness determination and critical depth determination, since channel deformation increases with sedimentation at the channel floor.  In this research, in order to obtain a clear understanding of the effect of wall and bed roughness on the flow pattern (longitudinal velocity and transverse flow), experiments were conducted on the flow in a direct trapezoidal channel. Variables in this test series are the average velocity (discharge 5, 6.6 and 8.2 L/S), roughness mode (all without roughness, only rough wall and all surface of the roughness channel), roughness (9, 12 and 15 mm) and depth of flow (13 and 16 cm). Speed measurements were made by a two-dimensional electromagnetic speedometer, accurate to 0.001 m/s. An inventive method has been used to measure vertical velocity, which is described in full in Chapter 3. By analyzing and analyzing the results of the experiments, it was found that with increasing average flow velocity, an accidental increase in roughness occurs, and velocity contours rotate away from the rough parts. When the only wall is rough, the contours tend to the middle of the channels width toward the bed, and with the addition of the roughness of the substrate, these contours are removed from the bed and somewhat back to the wall. The increase in average velocity increases the effect of the depth of flow on roughness, which is more tangible for a situation where the only wall of the roughness channel is rough. By increasing the size of the roughness and adding the roughness of the bed, it is observed that the secondary vortex flow moves toward the free surface of the stream and sometimes moves towards the wall, but there are also examples of defects indicating that it is not predictable The phenomenon of product is turbulence

تأمين آب موردنياز كشاورزي، صنعت و آشاميدني نيازمند برنامه­ريزي­هاي دقيق و درازمدت است. با توجه به مشكلاتي از قبيل خشك­ سالي­ها، كمبود بارندگي و مصرف بي­  hy;رويه­ي آب­هاي زير زميني در سال­هاي اخير، اهميت اين موضوع بيشتر شده است. از اين رو پيش­بيني متغيرهاي هيدرولوژيكي به ­منظور مديريت بهره­برداري از منابع آب امري ضروري است كه در اين بين تراز سطح درياچه­  hy;ها به­عنوان يك ميراث طبيعي اهميت ويژه­اي دارد. بدين­منظور استفاده از روش­هايي كه با صرف كمترين وقت و هزينه به دقيق­ترين نتيجه برسد بسيار حائز اهميت است.در اين پايان­نامه مطالعه­اي در رابطه با پيش­بيني تراز سطح درياچه انجام شده­است. اين مطالعه به اين شرح صورت گرفته­است. در ابتدا نرمالسازي داده­هاي تراز سطح درياچه در محدوده   انجام گرفت. پس از آن به انتخاب تركيب ورودي­هاي مختلف با استفاده از همبستگي­نگارها پرداخته شد. نتيجه آن شامل 16 نوع تركيب ورودي متفاوت است. پس از آن با اين 16 نوع تركيب مدلسازي بوسيله روش ELM صورت گرفت. سپس با استفاده از شاخص­هاي آماري، نمودارهاي رگرسيوني و نمودارهاي سري زماني اين 16 مدل با يكديگر مقايسه شدند و بهترين مدل برگزيده شد. مدل برتر در اين پژوهش مدل 3 معرفي شد و در نهايت نتايج اين پژوهش با نتايج ارائه شده محققين در گذشته مقايسه شد. نتيجه اين مقايسه به برتري مدل ارائه شده در اين پايان­نامه انجاميد.

  The dependence of the soils behavior on time may lead to structural and chemical changes in chemical and mechanical processes that lead to softening, hardening, loss of adhesion between particles, cementation, or changes in conductivity properties. The need to predict the properties and behavior that will occur in months or years will be a major engineering challenge. Time dependence can be attributed to the effect of long-term structural summation on the density of the earth, the deformation of ground structures, natural movements, and the drilling of slopes. In this study, the stability of sand gravel that is exposed to water flow has been evaluated over time. This analysis has been performed using both laboratory and numerical methods that have good and acceptable compliance. Also, the effect of resistance parameters (adhesion and friction angle) and slope angle have been evaluated by numerical modeling. The new relation presented from numerical results by using multiple regression shows an acceptable match, so that the overall relation presented with R ^ 2 = 0.86 shows good results.

  AbstractCollision of two flow in open channelsand its three-dimensional dynamic effectonthe on the sedimentation and distribution of water is a common phenomenon in natural rivers, irrigation and drainage networks, collect and guideof surface water systems, sewer and etc. Junctio  ecause of the effects on the flow structure including sediment tra  ort, results of measurement and pollutiondistribution in flow have an important effect in hydraulic engineering and this factorshave becomejunctionto the routine structures.Complex hydrodynamic of flow at the junctionsare dependent on many geometry and hydraulic parameters such ascollision of two channels angle, channel shape, slope, Froude number, Reynolds number, discharge ratio and the ratio of channel width.In this study, in order to reach a clear understanding of the physics governing on the flow field in open channel junction by a FLOW-3D software, VOF method and the RNG k-? turbulence model flow field in 90   junction in open channel numerical simulation and by using results of experimental studies, the results of numerical solution has been validated.Comparison between numerical results and laboratory measurements indicatedthe capability of numerical model for simulation of three-dimensional flow pattern in open channel junctions.The purpose of this studyputting obstaclein tributary channelto prevent sediment tra  ort from tributary-channel to main channel and reduce pollution in the main channel.In this study, aobstacle placed in the tributary-channel and to examine the various parameters of flow and compare this model to the simple junction.In this thesis tried that the influence of the obstaclewith 10 cm width at three points of tributary-channelsand at a height of 0.1, 0.2 and 0.3 m have be monitored on velocity parameters, shear stress, Froude number, water level changesAnd is trying to with transfer the obstacle with 10 cm width at various points of tributary-channelsand changes elevation that lead to an optimal model to be more appropriate hydraulic conditions.At first aobstaclewas placed at the end of tributary-channels by adding different width and 0.1 height and0.25 ratio of discharge that modeling and analysis by Flow-3d software and to more analyze and evaluate after the specified width, height change effects in different points of the tributary-channel is checked.After reviewing the results of model with obstaclein height and different point of tributary-channels,the model by the obstacle height determined where the hydraulic conditions more efficient than mode simple junction was selected.