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Sluice gates are commonly used to measure water discharge and to adjust the water level in open canals. Sluice gates can also be used at the crest of dam spillways for controlling floods. Estimation of head loss (∆E/E₀) and discharge coefficients (C_d) for a sluice gate is essential for the design of open canals. Depending on the downstream water level, free or submerged flow conditions may occur. Although there have been some investigations on C_d for sluice gates, a comprehensive literature review shows that there are no studies of ∆E/E₀ (to the best knowledge of the authors). Knowledge of ∆E/E₀ is necessary for the design of intakes and irrigation canal inverts. This study uses the physical model of sluice gate to introduce helpful charts for energy loss estimation. Experiments were conducted in the University of Tabriz, department of water engineering. A rectangular canal with length of 12 m, width of 0.5 m and height of 0.8 m was used. Vertical slide gate was installed at the 6 m from canal inlet to permit flow become uniform. Water circulation is carried out using a submerged pump. Water is pumped in a 4.5 m head tank and then inters to canal with pipes. Water level/depth was measured with a point gauge with 0.1 mm accuracy. Discharge was measured with a calibrated rectangular sharp crested weir. Experiments were carried out with different discharges and gate opening. Results show that ∆E for free flow is greater than that for submerged flow conditions. Meanwhile, discharge coefficients in a free flow are greater than those under submerged flow conditions. Relative energy losses (∆E/E₀) have a minimum value of 0.271 and a maximum value of 0.604. These high energy losses cannot be ignored in intake structures and canal-designing processes and their impact on minor canal inverts receiving water from main canals should be considered. The relative energy loss changed from the minimum value of 0.271 to the maximum value of 0.604. Multivariate regression method was used to calculate the relative energy loss and the average of the residuals was -0.004. The maximum and minimum residuals for ∆E/E₀ are 5 and -0.31, respectively. A mathematical equation with a coefficient of determination of 0.925 was presented to separate the boundary of free flow from submerged flow. To estimate the discharge coefficient in submerged flow, a mathematical equation was obtained. For this equation, the average of the residuals was -0.004. The maximum and minimum residuals for the discharge coefficient are -0.084 and 0.116, respectively. Application of multiple non-linear regression (MNR) models are presented for predicting ∆E/E₀ and C_d. The high energy losses cannot be ignored in intake structures and canal designing processes. Their impact on minor canal inverts receiving water from main canals should be considered. Application of MNR was presented from a simple equation to more sophisticated equations by improving regression relations in each step. The MNR method provides accurate equations for predicting performance for both ∆E and C_d.

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In order to facilitate the release of floods from the dams and to prevent their damage or collapse, a structure called a spillway is used. Due to the natural and variable flow of the input to the reservoirs of the dams, there are times when the river inflow exceeds the consumption amount in the downstream agricultural lands. In these cases, excess water is discharged over the crest of the weir and flows towards the spillway, which causes high velocities. This high velocity creates low pressure areas on the spillway concrete surface, which can cause major damage to the spillway or even endanger the integrity of the dam structure. Therefore, the dam spillway must safely dissipate the kinetic energy. One of the types of weirs is the stepped spillway to facilitate the passage of the flow over the dams. One of the most obvious practical features of stepped spillways compared to other spillways is the considerable energy dissipation along the spillway. Care should be taken in designing and selecting the type of spillway to prevent potential erosion and reduce kinetic energy as the water flow passes over the spillway. One possible solution is to use a stepped spillway instead of a smooth spillway. In this study, a numeral model of a stepped spillway with different steps and slopes is used. For this purpose, ANSYS software is used for modeling free surface with application of k-ε turbulence model. In the present study, numerical simulation using the Volume of Fluid (VOF) model was used to investigate the mixing phenomenon of two phases of air and water of the free surface flow. The flow field was continued until the residuals reached 10^-7. Compared to simpler models such as Mixture, which operates solely on the basis of averaging the properties of two phases, the VOF model, is separating the phases and considering the effects of the interface. The VOF model, is capable of more accurate simulation of phenomena such as fluid mixing, turbulent flows, and heat transfer in multiphase flows. A number of hydraulic specifications which are considered in designing the stepped spillways are the pressure on the surface of the steps, velocity distribution and energy dissipation. The results from the numerical models were compared with experimental studies. They showed acceptable agreement with physical simulations. Results show that discharge and spillway slope increment reduces the amount of energy loss. In the spillway with 5 steps, for a discharge of 0.063 m³/s, the amount of energy dissipation at a slope of 26.6 degrees changes from 85 to 82% at a slope of 45 degrees, which shows a decrease of 3%. With the increase in discharge, the flow depth increases and reduces the effect of the roughness of the steps on the upper layers of the flow. Increasing the height of the steps increases the rate of energy dissipation and also increases the occurrence of negative pressures in stepped spillway. In this case, the contact surface between the main flow and the eddy currents increases. With the increase in the height of the steps, the dimensions of the rotating vortices also increase and cause a larger radius of rotation on the steps. The presence of these large rotating vortices separates the flow from the bottom of the steps and reduces the pressure on the surfaces. The number and dimensions of steps can alter the energy dissipation rate. Increase in the number of steps in a spillway with constant height, reduces the energy loss as the result of steps dimensions being shrunk

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Foothills, plains, alluvial areas, and sloping areas whose soil is geologically susceptible to landslides, can become unstable and dangerous. In Iran, because of their soil type, Mazandaran, Gilan, Lorestan, Golestan and Khuzestan provinces are more vulnerable to landslides than other provinces. But taking into account factors such as earthquakes, extreme weather, and human interference, other parts of the country can also be prone to landslides. In case of rainfall and absorption of water by clay layers, the possibility of landslides increases. If the slope of the land is suitable, the slope will move on the clay layer and the thrust will occur downwards. In many mountains and steep areas, the conditions for slope failure may be available in terms of the slope angle, the type of soil and the presence of clay layers. But in the absence of sufficient soil moisture, this phenomenon is not observed. Landslides occur whenever rainfall happens and water penetrates the clay layer. Cutting down forest trees, destroying vegetation and pastures, along with possible rainfall and soil moisture, cam cause landslides on steep slopes. In fact, land use changes contribute to landslides. By examining the statistics over the last three decades in the northern provinces of Iran, it can be seen that landslides were far less likely when there was proper vegetation. The occurrence of heavy rains can cause failure in a large number of soil slopes. During these heavy rainfalls, the underground water level rises and increases the pore water pressure and reduces the stability of the soil. The purpose of this study is to investigate changes in pore water pressure and the factor of safety for slope stability. The flow of water inside the soil is numerically modeled as a two-dimensional, saturated-unsaturated, unsteady flow. The finite element method (FEM) is used to calculate the pore water pressure and the limit equilibrium method is used to determine the factor of safety for slope stability. To simulate the unsteady flow, time duration of 4 days is used with a time step of 0.1 days. The rainfall duration was assumed to be 24 hours. The intensities of different rainfalls are used as the input flux on the soil surface. The soil moisture curve, which shows the relationship between suction-moisture content and suction-hydraulic conductivity, is used. The results show that different rainfall intensities have different effects on soil moisture profile. As the intensity of precipitation increase, the factor of safety of slope stability decreases. This decrease is steeper for the first 24 hours of rainfall and over the three days after the rain stopped, its slope decreased. For example, for a rainfall intensity of 2.04 mm/hour and the duration of one day, resulted in a factor of safety of slope stability equal to 1.853, and at the end of the fourth day, it was 1.743. In other words, the factor of safety decreased by 5.9%.
 

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Investigating the role of narcissism in the tendency to doping in bodybuilding athletes

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Examining the dimensions of mental strength in the performance of athletes

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Sassanid reign, as one of the most powerful Iranian dynasties, lasted for over four centuries before the Arab Moslems’ attack to Iran. The great Sassanid government managed to convert the Feudal Iran of Parthian era into a united and strong country thanks to its central government and Zoroastrianism nationalism; this not only recreated political power but also hugely revolutionized the cultural and social issues in Iran. However, different factors, after a while, led to the gradual weakness and suppression of this dynasty before the Arab Moslems’ attack. In this research, auditing the historians of all these four centuries of the early Islamic era including Abou- HanifehDinvari, Yaghoubi, Masoudi, Tabari, and EbneMoskouyeh exactly and from all aspects, many attempts have been made to figure out and analyze the reasons of this gradual weakness and overthrown of Sassanid Reign the emnloying a historical-descriptive method. The results of this research reveal that in the view of the historians of all these four centuries of the early Islamic era, the following factors were the most crucial reasons of Sassanid’s downfall and defeat before the Arab Moslems: religious prejudice, high position of Zoroastrian clergymen, well-borns’ increasing power, massacre of the royal family by Shirouyeh, the last Sassanid kings’ lack of authority, a military coup against the kings, long exhausting overseas battles, especially the constant wars against the Rome Empires, toppling the Ale-Lakhm by KhosrouParviz, economic pressures on people and heavy taxes, natural disasters like the Tigris and Euphrates rivers bursting their banks, and hidden helps.

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Horizontal development of the cities has resulted in much destruction environmentally and economically. Two of the major consequences of such destruction is imbalanced development and inappropriate application of lands in the cities that are referred brownfield in this article. Brownfield in the urban planning jargon, a brownfield site (or simply a brownfield), is a type of land formerly used for industrial purposes or some commercial applications. The brownfield concept was first introduced by the British government and was used in accordance with the sustainable development policies which is mostly focused on the environmentally polluted lands. In the last two decades, redevelopment policies of brownfield as a crucial practical solution for preventing disperse growth of cities and also supporting the concentrated growth of cities have been attracted more attention. The main features of the brownfields are: -1 Pollution: each land in which an environmental complication has the occurrence probability. -2 Empty and leaved without using and in general lands and properties that their activities have been closed or not been used anymore. Of course, some of the terms that must be separated from the brownfield areas are: greenfields and grayfields.
Greenfields are those lands that previously has not been developed and often are rural or suburban. These green sites are located in the edge of small or large cities and have better accessibility and more palatability with additional space for future development.
The term grayfield, was defined in 1998 by new urbanism congress. Unlike the famous terms of greenfields (the rural undeveloped) and brownfields (polluted urban sites), the gray lands are called to the large undeveloped sites that have good reasons for redevelopment. The term of grayfield can be used to describe any kind of redevelopment that significantly is not polluted. But regarding the importance of environmental protection and sustainable development and realization their policies, it is essential to eliminate or reduce the environmental pollutions purposefully to achieve the redevelopment of brownfields.
For the sake of importance and novelty of the subject, redevelopment of Brownfield with the objective of efficient applications of lands in cities and reducing the environmental pollution and also improving the social-economical context of these fields is the subject of this article. Brownfield of Kan stream in Tehran was selected as the case study. The field was selected as it is one of the few major barren Brownfield in Tehran. They are not only in the leaved brownfields but also regarding the river-valley nature, the fields has specific ecological and tourism features. Unfortunately, due to lack of planning and management, these brownfields have been converted to the locations of rubbish depot and uncontrolled polluted waters and therefore infected with the environmental pollution. The methodology of this article is descriptiveanalytical using library studies. After studying the theoretical framework, defining features of brownfield, literature review, objectives and the importance and of these fields, the redevelopment process of Kan stream Brownfield are presented. Finally, the conclusion and analysis of the actions are conducted in redevelopment of brownfield with social, economical and tourism approach.
After comprehensive studies, in order to determine the kind of landuses in Kan brownfields, establishing a national and even an international performance scale park is designated as the planning vision. In this context, the objectives of the redevelopment planning process Kan brownfield included:
creating a touristic space to enhance the region›s tourism identity, planning with emphasis on providing recreational services for all social classes, such as children, elderly people and women and people with disabilities (all divisions with regard to sex, age and physical aspects), strengthening of the relationship between people and nature and to replacing normal social activities and improvement environmental conditions; Developing ecotourism in urban environment regarding and it s benefits beyond natural landscapes, enhancing green space for per capita in Tehran city and attainment to the standard limits for
environment qualities by using marginal lands and rivers sanctums.steel plates. In addition these bars are pre- tensioned by means of cable passing through them in order to behave properly to the applied forces.
The way that the bars are moved through the retraction process and the function of the building effects on the selection of the covering materials. In this structure, as the distance between the bars is changed during the deployment process it is required to use a flexible but strong material that can resist repeated retraction. Therefore, a flexible membrane that is strong enough during movement and has a proper foldability such as ETFE is one of the best alternatives for covering the roof. ETFE is also able to penetrate enough light inside of the building when the roof is in fully closed position and this in turn reduce the energy required for running the building.
The membrane is also attached to the bars though the slots that have already been created during fabrication and is fasted by means of pinned curve plate. This is also worth to mention that in this structure, the placement of the moveable components underneath the covering material support the whole structure even in severe weather conditions. Therefore, this increase the life cycle of the system and decrease the maintenance cost.
In summary, this paper proposes a new solution for a retractable curved roof system that can not only be transformed from an open to closed configuration but is also able to support itself structurally even during movement and transformation. In other word, the structural and transformable components are integrated and are able to make the whole structure stable during transformation.

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The water fern weevil, Stenopelmus rufinasus Gyllenhal (Coleoptera: Curculionidae), is considered as the most important biological control agent of Azolla spp. in the world. Azolla spp. was introduced in Iran in 1986. In August 2017, two specimens of S. rufinasus were collected on Azolla spp. in waterways near Anzali lagoon and Rice Research Institute of Iran (RRII) in Guilan province for the first time. Identification was based on molecular sequencing. This is the first record of S. rufinasus from Iran.
 

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Hotels are fundamental elements of tourism industry and provide various services for tourists. Moreover, hotels development has an important impact on tourism industry development. Therefore, an understanding of hotels relative efficiency performance, over a period of time, is important for practitioners, analysts, and policymakers alike. The main objective of this paper is to measure the efficiency of the four and five stars hotels in Tehran. A Data Envelopment Analysis (DEA) is employed to investigate the technical efficiency of eight hotels using the data over the period 1380 - 1384. DEA analysis is a methodology for analyzing the relative efficiency of units having the same multiple inputs and multiple outputs. In this study, the input variables comprise employee, rooms, restaurants and land and the output variables include hotel income and occupancy rate. The results show that technical and scale efficiency scores in all periods are relatively higher but there is no a regular trend over the period under study. Since 1380 to 1384; 75, 62.5, 75, 62.5, and 50 percent of the selected hotels were respectively efficient under the constant and variable to scale assumptions. Moreover, the findings confirm that more scale efficiency (0.997) refers to 1380 and less scale efficiency (0.894) refers to 1381 and 1382. The results also show that more technical efficiency, on average, under variable to scale assumption (0.964) refers to 1380 and less technical efficiency (0.894) refers to 1384. Finally, the efficiency of the five stars hotels is more than the four stars hotels implying the priority of the five stars hotel’s development in Tehran. Overall, the findings indicate that the particular problem is mismanagement in the Tehran’s hotels. Consequently, it caused the average scale efficiency to be more than the average technical efficiency. Since management plays a vital role in the efficiency improvement of hotels, this paper suggests the improvements of managerial systems in the hotels. More specifically, education, employment and Customer Reservation Systems (CRS) are the main factors influencing the efficiency.

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In this study, pulsating hydroforming of tube in a box die is simulated using the three dimensional finite element method to investigate the mechanism of improvement of the corner filling. In addition, the results obtained from the simulation are compared with experimental observations, and the validity of the simulation results is verified. Based on a better understanding of the mechanism of improvement of the corner filling, a new pulsating pressure path is proposed to increase the corner filling. It has been shown that the proposed pulsating pressure path is more effective in increasing the corner filling of the box shape tube hydroforming process.

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The aim of this paper is twofold. It first investigates the demand for international reserves using panel data for 32 developing countries during the period 1975 – 2004. To this end, an Error Correction Model (ECM) approach is employed to estimate the empirical model and then a capital asset pricing model (CAMP) is used to determine the composition of the foreign exchange reserves. A dummy variable is included in the model to consider the effect of changing exchange rate system on the demand and the composition of international reserves. The results show that there is a negative relationship between exchange rate flexibility and the demand for international reserves.

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Aluminum alloys are desirable in industry due to their excellent high-strength to weight ratio, corrosion resistance, and weldability. However, at room temperature, the formability and the surface quality of the final product of these alloys are low. So in recent decade, new process, hot metal gas forming, has been introduced. This paper investigated new method of hot aluminum alloys forming using gas. Experimental test for bulge forming was designed and made. In addition to experimental test, finite element analysis of process was done. Results showed that hot metal gas forming provides highest forming temperature for aluminum alloy blank and with increasing blank temperature up to optimum temperature of hot forming, there is reduced pressure forming and significant improvement of formability. Results of experimental test and finite element analysis including determination of optimum temperature for forming of special aluminum alloy, maximum formability in this process, required forming pressure, minimum thickness, thickness and temperature distribution were conformed.

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In this study, the effects of powder and leaf extract of Moringa oleifera on hemolymph factors of Litopenaeus vannamei in response to salinity stress were evaluated. After 8 weeks of feeding with powder (25, 50 and 100g / kg) and extract (0.25, 0.5 and 0.1 g/kg) leaves of Moringa and control treatment without Moringa, all treatments were exposed to short-term salinity stress (5 and 55 ppt). There was a statistically significant difference in total and differential count of homocytes in different dietary treatments in all three normal conditions and under salinity stress of 5 and 55 pp (p<0.05). Under normal conditions and high salinity, shrimps fed with Moringa leaf extract showed higher number of homocytes than other treatments. In stress-free conditions, the number of semi-granular cells in powder and extract treatments was higher than the control group. At 5 ppt, Moringa powder treatments had higher semi-granular and at 55 ppt salinity, the leaf powder group (100 g/kg) and the leaf extract (0.25 g/kg) showed the highest values, respectively. Overall, the results of this study showed the positive effects of using Moringa leaf powder and extract on innate immune system function and exposure to salinity stress in shrimp
 

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Abstract
Urinary tract infection is one of the most common and common bacterial infections, accounting for a significant proportion of hospital admissions (about 30-40%). Silver nanoparticles work by releasing silver ions against various bacteria. The fact that bacteria are not resistant to nanoparticles is very important and therefore will affect a wide range of bacteria.
Materials and Methods
In this study, 50 specimens of positive cultures with urinary tract infection referred to Imam Reza Hospital Laboratory in Bojnourd were studied. Resistance and susceptibility of the isolates were determined by disk diffusion method. In this study, antibacterial effects of silver nanoparticles were investigated by microdilution method using aqueous extract of Ganoderma leucidum. Vegetative electron microscopy was used to measure the size and shape of silver nanoparticles. In addition, infrared spectroscopy analysis was performed to investigate possible organic compounds involved in the synthesis of nanoparticles.
Results: The highest antibiotic resistance was related to ampicillin (84%). The resulting nanoparticles were 20 to 45 nm in size.
Conclusion:
The produced nanoparticles have antimicrobial activity and can be a good alternative in the treatment of antibiotic resistant infectious diseases.
 

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Abstract

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Abstract- This research develops a Lamb wave technique to determine the dispersion curves of a two layered bonded component: an aluminum sheet attached to a composite layer by means of a cohesive. A commercial finite element code (ABAQUS Explicit) is used to determine the dispersion curves of the Aluminum-cohesive-composite multilayer component. The finite element model includes three plain strain layers that the middle one is cohesive. Then a lamb wave is propagated in the model and some output signals are received. The dispersion curves are obtained by using 2D Fourier transformation of finite element model output signals. In addition, to produce various modes, experiments are carried out on a composite-aluminum assembly using two 2 MHz variable angle transducers. Comparison of modes obtained from finite element method and experiments shows that group velocities are almost identical. Hence, good agreement between finite element method results and experimental results indicates that finite element is reasonably accurate for determination of dispersion curves.

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This paper evaluates the efficiency of using surface water simulation results to improve the accuracy of groundwater simulation due to improving the accuracy of its input boundary conditions. The three most important data sets of boundary conditions in groundwater flow simulation are groundwater recharge, evapotranspiration rates and their regional distributions that little information is usually available about them. Moreover, the incorrect definition of these values can lead to uncertain groundwater modeling that is not applicable for groundwater resources management. In the most of previous studies done in Iran, percentage of the average regional precipitation and the local pan evaporation data (available from local weather stations) are used as the regional groundwater recharge and evapotranspiration rates, respectively but they have high uncertainty in their quantities and spatial distributions. In this research in order to solve this problem, the values of groundwater recharge and evapotranspiration rates and their regional distributions, obtained from SWAT modeling results, were used as the related input boundary conditions data in groundwater flow simulation using MODFLOW model. SWAT model is a comprehensive watershed model that calculates these values in each Hydrologic Response Unit (HRU). The study aquifer in this research was Silakhor shallow aquifer with the area of 590 km2 located in Lorestan province of Iran. The annual water table depth in different locations of this aquifer had been reported from 0.75 to 40 meter. Using this approach for improving boundary conditions in groundwater simulation and its evaluation was carried out for first time in Iran. The SWAT model was run for a period of 7 years from 2002 to 2008. After calibration and verification of the model using hydrodynamic data of Silakhor and Tire-Doroud gauging stations, the values of groundwater recharge and evapotranspiration rates in each HRU were extracted. The MODFLOW model was run for the period of 9 months of 2009 using these simulated boundary conditions and the other required information. For comparison of the calculated values with the observed values of water table depths in the 20 piezometers for the period of 9 months of 2009, the Root Mean Square Error (RMSE) and Mean Absolute Errors (MAE) were obtained 1m and less than 1m, respectively. In continuous of this research, the values of 5, 10 and 15 percent of regional average precipitation and the evaporation data in Silakhor pan evaporation gauging station were used as usual boundary condition for groundwater simulation using the MODFLOW model. For comparison of the simulated values of water tables depths obtained from this usual approach with the observed ones, the both of RMSE and MAE values were calculated more than 1 meter. Therefore this research showed that using integrated SWAT-MODFLOW models was more applicable in the groundwater simulation in the study aquifer.

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A consistent implicit Incompressible Smoothed Particle Hydrodynamics (ISPH) method based on projection approach is proposed for solving violent free surface flow problems. In this way, two consistent discretization schemes are employed for first and second spatial derivatives. In this study, it is shown that in explicit ISPH solvers, the field variables and the positions of particles in the process of numerical differentiation are estimated at two different time steps. So, the incompressibility is not completely satisfied. In the present approach, an iteration loop is implemented, in each time-step. Thus, at the end of each time-step both velocity and the positions used in divergence estimation are at the new time-level. The proposed ISPH method is validated in free surface flow problems involving 2-D dam break benchmarks in which both wet and dry beds are considered. Among the advantages of the present implicit method is being more accurate and stable than the explicit one, despite use of lower number of particles and greater time-step sizes. Also, it provides significant improvement in free surface simulations and pressure distribution results.