One of the important aspects in describing river behavior is its curvature. The production of successive bends in natural rivers is an inevitable component of the process through which the river changes. Understanding the flow behavior in the interaction between the main channel and the floodplain, especially during floods, is necessary to protect soil and water structures. This study was conducted to better understand the hydrodynamics of the middle and turbulent flow in compound meandering channels. According to the natural conditions of most rivers, due to variation of discharge and depth ratios (flow depth in floodplain to flow depth in the main channel), in this study, a rectangular meander laboratory channel with a constant sinuosity 1. 3 for different depth ratios of 0. 35 and 0. 55 was investigated. The results showed that the size of velocity components (u, v, w) at 0. 35 Relative depth was greater than 0. 55, which indicating higher vortex strength and interaction intensity between the main channel and floodplain at lower Relative depth. Also, by investigating the secondary flows, the existence of clockwise and counterclockwise rotational eddy currents in the main channel and floodplains and the location of these currents were determined.

The rivers, as the main watercourse and natural drainages, always play a significant role in the conveyance of flood flows. During floods, the water crosses the main section of the river and enters the floodplains. In this case the river crossing becomes a compound cross section. In present research work, by studying meandering compound channels, the effect of changing Relative depth of flood currents on the hydraulic flow conditions and the rate of discharge are investigated. For this purpose, six channels with different sinusoidal rates at three Relative depths with different flood rates were investigated by FLOW3D software. The results of numerical simulation show that by increasing Relative depths from 0.26 to 0.45 (73% increase), the depth averaged velocity in all channels increased by 25% and the rate of discharge passing through the main channel decreased by 33%. Also, the results of this study show that the bed shear stress near the inner arch of the main channel is more than the outer arch and by reducing the Relative depth in the compound channel, the amount of bed shear stress and flow velocity decreases. And the amount of shear stress of the inner arch wall of the main channel in all channels is higher than that of the outer arch wall, and by increasing the Relative depth the amount of shear stress of the wall is increased.

Flooding of rivers is accompanied with a threat on the population living on their floodplains and on the neighboring settlements. Accurate modeling of such flows is thus imperative to assess flood risks, perform real-time flood routing, or estimate the impact of a mitigation schema. The converging of the compound channel causing the flow become even more complicated. The flow patterns in converging compound channel and free-surface profile has been simulated by using RSM turbulence model and VOF method, respectively. The comparison of the experimental results including longitudinal free surface profiles, depthaveraged velocity distribution and the ratio between floodplains and total discharge confirmed that the numerical simulation can be used to model the flow pattern in converging compound channel. Furthermore, Absolute Percentage Error (APE) for each of these parameters was amounted to 3. 25%, 4. 66% and 9. 72%, respectively. Respectto the numerical simulation capability in anticipating the flow field parameters, we investigated the effect of Relative depth on the flow patterns in a converging compound channel. Moreover, the flow parameters including velocity distribution, depth-average velocity, secondary flows, ratio between floodplain and total discharge, bed sheer stress and energy dissipation were investigated in different Relative depths h* (0. 1, 0. 2, 0. 3, 0. 4 and 0. 5). By evaluating and comparing the flow results in the different Relative depths, we came to conclusion that the longitudinal-average velocity in the main channel increased as the cross section was narrowed. However, the longitudinal-average velocity in the floodplains decreased in the Relative depths of 0. 1 and 0. 2 as the cross section was narrowed. In contrast, this parameter increased in the Relative depths of 0. 3, 0. 4 as well as 0. 5 the floodplains narrowed. Velocity gradient between the main channel and floodplains in the Relative depth of 0. 1 was strong and in the Relative depth of 0. 5 was insignificant. In the smaller shallow depth, this velocity gradient has been resulted in secondary flow in the cross section of converging compound channel. Accordingly, in the Relative depth of 0. 1 and 0. 2 four cells of secondary flows were formed and in the Relative depth of 0. 3 just two cells of secondary flowswere formed. The secondary flows in the Relative depths of 0. 4 and 0. 5 was eliminated. Convergence in the length of main channel get the discharge conveyance copacity of floodpland to decrease. furthemore by decreasing the Relative depth the capability of floodplains to conveance the discharge was significantly dicreasead. This decrease was evident in the depth of 0. 1 in which the ratio between floodplain and total discharge was amounted to 2. 52%. Sheer stress in channel bed increased when the Relative depth of the main channel increased and the maximum amount of bed shear stress was happened at end of the channel. On the other hand, in the floodplains, this parameter decreased along with the converging in the lower Relative depths (0. 1, 0. 2) and for the other Relative depths the bed sheer stress increased along with converging. In channel inlet the maximum and minimum amount of energy dissipation was resulted at the Relative depth of 0. 1 and 0. 5 repectively.

Due to the importance of Tabriz in various historical periods after the Mongol’s invasion to the end of the Qajar period, as continuously being the capital city or the residence city of the prince, entrance to this city has been reflected in various reports. Most of the foreigners who entered Iran from European countries came from Caucasus Road to Tabriz and reported many buildings on their way. Moreover, this road was one of the most significant roadways for Caravans on the Silk Road, where various residential buildings have been constructed. Alaki caravansarai is one of the most important roadside accommodations in Northwest Iran, and so many reports about it and the quality of its façade decorations can be traced in the travelogues of foreigners who traveled to Iran. Its vastitude and elegant entrance gate nevertheless, this building has unfortunately been neglected and was about to be ruined in the 19th century and afterward. However, the beauty of its entrance gate has gained the attention of many people and has been reported in many sources. Based on the ornaments used, recent sources in the history of architecture have estimated its date to the 12th century and Ilkhanid Abū Saʿīd Bahādor Khan and the Timurid period. These sources based their estimation only on the type of ornaments used on its entrance gate and its probable that the existence of dated artworks of the Ilkhanid period nearby, such as the Mihrab of Marand’s Jame Mosque, has influenced this speculation. This article aims to meticulously study this building in various travelogues, al-Wqafīyya al-Rashīdīyya, and other sources in the history of architecture and discusses the ornament types used and their history. The detailed study of the documents and sources indicated that this building could belong to the presidency period of Ḵᵛāja Rašid-al-Din Fażl-Allāh, and based on his emphasis to establish this building, can be dated 1297-1309. The ornaments, moreover, indicate the transient period from brickwork to tilework which happened in the late 13th and early 14th centuries

There are different types of space in each house, which have different positions in terms function. the functional action of each of these spaces has a direct impact on the performance efficiency and consequently allocation of weights to different spaces. one of these spaces that has a great impact on the variation of this area is the space of the ” yard” . The aim of this s tudy is to inves tigate and evaluate the fanctional efficiency of the yard space by emphasizing the concept of functional radius in different types of patterns of traditional Iranian homes. In order to perform the mentioned process, mathematical relations will be used in terms of space syntax, which is specifically applied to the Relative depth decline function in order to analyze and prove the problem. In the s tudy using Relative depth descent function, we need to convert qualitative information to quantitative data. The extraction and conversion of these data is made possible by drawing graphs or briefings, which is actually the use of space syntax method. by examining the Relative depth in different types of house patterns, indicators such as functional radius, effective diffusion domain and optimal space efficiency can also be extracted which is effective in determining the value of the yard space as a service space is effective in dealing with the needy Serve space. The firs t s tep in this s tudy was to draw the explanatory plots or graphs of each house used for this purpose by the "Agraph" software. In this connection, the "courtyard" space is considered as the root zone (server space) and the order of other spaces to the courtyard layout is measured as needly serve spaces. The results show that the decrease in the depth and thus reduce the amount of functional radius and, of course, an increase in effective penetration area is effective in determining the fanctional efficiency in the yard. Furthermore, the results of the s tudy show that, according to the definition of the "optimum fanctional efficiency" index, effective performance radius-which is under the set of operating radius of contract-each of the space (which is defined in the framework of space definition) has a direct relationship with the value of space. At this level, the required information is extracted from the jus tification diagrams and used to use in syntactic relationships. Therefore, the method of research in this s tudy is descriptive analytical. In this research, in order to determine the functional efficiency of space, jus tification graphs and syntactical maths are used. Accordingly, the research ques tion in relation to the research goal is as follows: How does changing the functional radius in space increase or decrease the efficiency of the yard in the Iranian home? Accordingly, the hypothesis on the answer to the research ques tion is as follows: The greater the functional radius of a space in the configuration of the building, the effective radius and the sphere of influence of that space decrease, and thus the efficiency of the space increases.

Background and Objectives: One of the main reasons for the failure of bridges in the United States and around the world is scouring. The flow characteristics, the base shape and the angle of its deposition Relative to the flow and characteristics of the sediments are all factors that interfere with the complexity of the scouring problem of bridges. It should be noted that the final scour depth created near the bridge base is equal to the total erosion depth due to local, general and narrowing of the flow width. Since the propagation of the scour hole threatens the sustainability of the bridge structure, predicting the amount of dirt and adopting the necessary measures for its containment are considered as common engineering measures in river engineering. Materials and Methods: In this study, the effect of air foil lattice collars on aerodynamic bridge foundations was investigated. In order to investigate the research in this study, a flume was used at Azad University of Ahvaz with the following characteristics. The input and output channels of the flume are a rectangular weirs with a Plexiglas sheet, so that the length of the direct input channels at the beginning of the flume and the output at the end of the flume are 4. 5 and 2. 5 meters, respectively, the width and height of the flume are 0. 5 and 0. 6 meters and the body of the flume is at a height of 0. 7 meters from the ground. Results: By installing the collar at a Relative depth of 0. 1, the length of the collars of the scouring net was reduced compared to the collarless base. By installing the collar at a Relative depth of 0. 5, the lattice collars with Relative lengths of 6, 8 and 10 were 35. 2, 37. 4 and 38. 4 percent, respectively, to reduce scouring compared to the collarless base. Also, by installing the collar at Relative depth (Z/D)=1 with a length (L/D) of 6, 8 and 10, collars were 27. 7, 31. 6 and 31. 4 percent compared with a collarless bridge pier, respectively. By increasing Relative velocity (V/Vc) from 0. 54 to 0. 95, on average, the scouring increased by 113. 8%. By installing the collar at a Relative depth (Z/D) of 0. 1, 0. 5 and 1, 16. 6, 35. 2 and 27. 7 percent lower scouring were observed compared with the collarless base. Also, by increasing the depth of the lattice aerodynamic collars the scour reduction decreased by 22. 3 percent. Conclusion: It can be concluded that the best depth of the collar is about half the diameter of the base of the bridge. Also, simulation with the Flow-3D math model is close to the physical model and has an average of only 4. 5% error, which is acceptable.

Identifying the constraining factors of production and yield gap is very important. Therefore; this research was performed to identify the production constraining factors of local rice cultivars. All management practices from nursery preparation to harvesting stages for 100 paddy fields of local rice cultivars were recorded through field studies, in Sari, from 2015-2016. In the CPA, the actual and calculated potential yield were 4495 and 5703 kg/ha, respectively and the gap was 1221 kg/ha. The yield gap caused by number of top-dressing variables was 324 kg/ha, equal to 27% of the total yield gap. The yield gap related to previous year of legumes cultivation was 218 kg ha-1, equal to 18% of the total yield variation. Among the 10 variables entered in the CPA model, the effects of top-dress fertilizer application and its application frequency and foliar application were remarkable, which could compensate a significant part of the yield gap (444 kg/ha, 37% of total) in the farmers’ fields by managing these variables. According to boundary line analysis (BLA) finding, actual yield mean on the basis of optimal limit related to 12 variables under study was 5369 kg/ha, with 881 kg/ha yield gap . Mean Relative yield and Relative yield gap for 12 variables (transplanting date, seedling age, number of seedlings per hill, planting density, nitrogen and phosphorous per hectare, nitrogen before transplanting, harvesting date, lodging problem, pest problem, diseases problem and weeds problem) were 83.64 and 16.35 kg/ha, respectively. Based on the finding, it can be stated that the model precision is appropriate and can be applied for both estimation of the quantity of yield gap and determining the portion of each restricting yield variables.

Flow in compound sections, due to the differences in velocity between the main channel and floodplains, is structurally quite different from that in simple channel sections. In the present research work, FLOW3D software was applied in a rough rectangular compound channel with single floodplain. The model geometry was selected from the experimental channel by Bousmar (2002), and the numerical solution results were validated by comparing the depth-averaged velocity parameter. The purpose of this study was to investigate the effects of roughness, depth and Relative width on flow velocity distribution, bed shear stress variation, and location of maximum stress in compound channel sections and simulated flow for 3 Relative roughness values of 1, 2 and 2. 9. Results showed that flow rate difference between the main channel and floodplain as the generator of shear stress and secondary flows in those sections increased by 3 times. Relative roughness for the Model A, 33. 5% and for Model B, increased by 15. 12%. While the Relative depth parameter increased from 65% (from 0. 2 to 0. 33), the difference for the two models A and B decreased to 36. 32% and 37. 85%, respectively. So, it seems that using Model B is more appropriate for high Relative roughness. Also, by increasing the Relative depth from 0. 2 to 0. 33 in all the Relative roughness values studied, the location of maximum shear stress for both models changed from the main channel to the floodplain.

The present study investigated the characteristics of hydraulic parameters of Sloped Gabion Drops and Simple Drops. Therefore, 120 different experiments were performed on both types of sloped gabion drop and sloped simple drop with three angles and two heights. Results showed that by increasing the Relative critical depth in both tested models, causes a reduction in Relative energy dissipation rate but an increase in Relative downstream depth. Comparing the results for sloped gabion drops and sloped simple drops showed that the use of gabion structures with three angles and two heights which, have been investigated, increases the average energy dissipation efficiency 561% and the average downstream Relative depth 50. 1% compared to the simple drops. So, this results in a decrease in the erosion of the downstream bed of the structure and the length of the pool. The results showed that as the angle of incline increases, the average energy dissipation efficiency decreases and, the average downstream Relative depth increases. The results showed that the change in the angle of the incline in sloped gabion drops had a Relatively small effect, in comparison with the simple drops due to the physical properties and the complex hydraulic effects of the flow through the porous structure. Also, some relationships were presented to estimate the Relative energy dissipation rate and the downstream Relative depth rate in the sloped gabion drops by using 80% percent of laboratory data, and the rest 20% of the data were used to test the relationships with the evaluation criteria.

The communities of the Kura- Araxes cultural complex with their highly distinctive cultural and economic features represent the occupation of some parts of the Near East and Caucasia during the Bronze Age.  Generally, the origin of this culture is sought in the Southern Caucasus. In Iran, the spread of this cultural tradition represents not only a rupture in the cultural development of the Mesopotamian traditions. Environmental changes linked to Rapid Climate Change (RCC) also forced the population to develop new economic strategies. Until about two decades ago, knowledge of the flourishing Kura Araxes occupation was limited to the north-west of the country and to some parts of the Central Zagros, but recent research in the zones south and north of the Alborz Mountain Range, on the northern edge of the Central Plateau allows by now to present a more detailed picture of the Kura Araxes occupation in both diachronic and synchronic perspective. Recent archaeological excavations in the two sites of Qaleh Tepe and Ali Yourd Tepe revealed some important new data from Kura-Araxes settlements in the corridor of the north Central Plateau and northwestern Iran. The two sites are located in the eastern Zanjan Province in the Abhar Rood Basin. This paper aims to update the chronology of the Kura-Araxes culture based on the radiocarbon dates from the two sites of Qaleh Tepe and Ali Yourd Tepe. The stratigraphy and radiocarbon dates of the two sites reveal the beginning of the Kura-Araxes culture in the region from c. 2900 BCE, followed by a quick extension into the northern Central Plateau, where it is represented by sites such as Shizar, Doranabad, Ostur, and Barlekin. Similarity and diversity characterize the Kura-Araxes cultural complex.  However, based on the current data, the ceramic style represents a common feature, but also the architectural remains indicate a common cultural tradition during the first quarter of the third millennium BCE in the Central Zagros, northwestern Iran, and on the Central Plateau