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Flow pattern is an important factor affecting fish collective behavior. In the reproductive season, schizothorax prenati will choose suitable flow area for migration, but the water conservancy project caused serious damage to its migration channel. The purpose of this study was to study the response of the collective behavior of Schizothorax prenati to the flow velocity and turbulent kinetic energy, to optimize the flow pattern and water management of the fish crossing facilities. In this paper, the Nearest Neighbor Distance (NND) and collective area were used to evaluate the cohesion of fish, and the Separation Swimming Index (SSI) was used to evaluate the repulsion of fish. In the experiment, 10 Schizothorax prenati with an average age of 3 years were selected from each group, a total of two groups, and each group was tested for 6 times. Each time allowed the fish to swim in a 3 m×14 m rectangular flume physical model (flow velocity decreased from 0.17 m/s on the left to 2.5 m/s on the right, and the turbulent energy was 0-0.225 m² /s2 ) and (16±1) ℃ water temperature. After shooting with the camera, the graph was collected to extract and analyze the swimming trajectory of the fish, at the same time, we observed the formation of fish in moving water and all collective indicators were calculated at 10-second intervals during the analysis of the fish. All coordinates recorded in a total of 12 tests were plotted as heat map, the darker the color, the more likely the fish were to cluster in that area, meanwhile, we calculated the NND, collective area and SSI of fish at all recorded times. Finally, by coupling the above three collective indexes with flow velocity and turbulent kinetic energy, the collective indexes under different hydraulics conditions were analyzed to evaluate the collective behavior of fish. The results showed that Schizothorax prenati had obvious collective behavior under specific hydraulic conditions, and its collective behavior was closely related to hydraulic factors. In this experiment, the fish mainly swam in the formation of “schooling” mode, and fish usually swam in a single partition in the experimental flume, showing a neatly arranged polar structure, and all individuals tended to swim in the same direction when the flow velocity was 0.27-0.70 m/s and the turbulent kinetic energy was 0.004-0.018 m² /s², the NND, collective area and SSI of the fish were 0-0.80 m, 0-5.00 m² and 0-1.20, and the collective behavior was the most compact and close, with better cohesion and repulsion. In the two typical swimming upstream routes, the average flow velocity and turbulence kinetic energy were basically consistent with the compact collective behavior hydraulic conditions of the Schizothorax prenati summarized in this paper, which verified the accuracy of this study. Therefore, it is recommended that engineering measures be taken to create a flow velocity of 0.27-0.70 m/s and a kinetic energy of 0.004-0.018 m² /s² in order to make the Schizothorax prenati mass migration, which allowed for a smaller flow velocity range than traditional fishway design methods. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Engineering Geology / Gongcheng Dizhi Xuebao is the property of Journal of Engineering Geology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Engineering Geology / Gongcheng Dizhi Xuebao is the property of Journal of Engineering Geology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ordnance Industry Automation is the property of Editorial Board for Ordnance Industry Automation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chemical Engineering of Oil & Gas / Shi You Yu Tian Ran Qi Hua Gong is the property of PetroChina Southwest Oil & Gas Field Company and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Yellow River is the property of Editorial Board of Yellow River and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Yellow River is the property of Editorial Board of Yellow River and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The plants in the river not only purify the water quality, but also increase the resistance of the river and raise the water level. Therefore, the resistance of river with plants is one of the current research hot spots. Plastic grass was used to simulate vegetation, and an open channel with trapezoid cross section was built to study the influence of water depth, velocity and plant spacing to the resistance of open channel with submerged vegetation in this paper. Through the force analysis of the research water body, the calculation formula of the average shear stress of the bed surface was derived. According to the test results, the average shear stress of the boundary under different conditions was calculated and the change rule of the shear stress of the open channel under different flow conditions and different plant densities was analyzed. The results show that the flow velocity and plant spacing have a great influence to the boundary shear stress, while the water depth has a relatively smaller influence to the boundary shear stress. [ABSTRACT FROM AUTHOR]

In this paper, the causes of mass loss of throwing materials in flood control of the Yellow River were analyzed and the stress analysis model of throwing body in moving water was established with gabion as the research object. Based on the force analysis of gabion, the influence of the velocity and depth of the dangerous section to the stability of the throwing materials was studied. The results show that increasing velocity and water depth can lead to poor stability of the throwing materials in the dynamic water and increasing weight (size) of throwing materials can effectively reduce the displacement and enhance its stability. Finally, some measures are put forward, such as designing a reasonable weight throwing materials, reserving enough throwing distance or using linked gabion system to ensure the stability. [ABSTRACT FROM AUTHOR]

In order to study the diversion effect of repeatedly assembled diversion pile dam in the lower Yellow River and to control the abnormal river regime in the lower Yellow River, the paper took an impervious pipe pile dam as the research object and adopted the method of moving bed model test to analyze the velocity distribution and the shape of the main flow line of the impervious pile dam under different flood conditions (Q=800, 4 000,8 000 and 12 000 m3/s)and the position of top wash. The results show that with the increase of peak discharge, the velocity of the river section is increased, and the top scour position of the flow is gradually moved downward and the main flow is close to the pile dam. The impervious pipe pile dam can control and guide the river regime of the lower Yellow River. [ABSTRACT FROM AUTHOR]

In order to solve the nonlinear problem of runoff concentration caused by excess rainfall intensity,a method deriving time-variant distributed unit hydrograph (TVDUH) based on the SCS's velocity equation was presented in this paper. A reference rainfall intensity is introduced to represent the hydraulic conditions corresponding to k values. A dimensionless factor formed by the ratio of duration excess rainfall intensity to reference rainfall intensity is added in SCS's equation to make up a new velocity equation that can take into account of the influence of excess rainfall intensity on flow velocity. The modified SCS's equation is used to derive the TVDUH of each rainfall duration during a rainfall event. A rainfall-runoff hydrological model is constructed of TVDUH and the runoff generation module of Xin'anjiang model. The rainfall-runoff hydrological model is used in Peihe River basin to calibrate the reference rainfall intensity. Application is performed in Tanjiahe River basin for validation. Results show that the number of events whose coefficient of efficiency being greater than or equal to 0.9 increases from 42% of time-invariant unit hydrograph to 83%. It is concluded that the presented method can contribute to increase the rainfall-runoff simulation capabilities of watershed hydrologic models observably. [ABSTRACT FROM AUTHOR]

In this paper, The FLUNET numerical simulation software was used to establish two-dimensional model, loading velocity, pressure and wall roughness. The flow field of the channel was calculated by using FLUENT numerical simulation software to calculate the flow field of the same flow rate and section velocity profile. The relationship between flow rate, flow velocity and roughness was studied in order to provide the basis for choosing the roughness coefficient correctly in practice. The results show that for the concrete bag lining channel, flow velocity and discharge are the factors of roughness. Through data correlation analysis, roughness is negatively correlated with velocity and discharge,the velocity gradually increases along the direction of the channel's bottom, but the maximum velocity occurs below the water surface and the lateral flow from the channel wall to the central flow, resulting in a larger velocity concentrated in the middle area. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)