• Journal of Environmental Science International
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• v.21 no.11
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• pp.1395-1406
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• 2012

The purpose of this study is to analyze the hydraulic characteristics of the ice-harbor fishway by considering its geometrical form and utilize such analysis results as the foundational database to be used when establishing fishways in the future. first of all, the study realizes the same form as an ice-harbor fishway that is currently implemented via a FLOW-3D model and estimated the parameters that were optimal to the numerical mock test. Then, this study analyzed the level of sensitivity of the flow conditions which fluctuated due to the changes in geometrical changes by adjusting the inclination and pocket spacing by using the estimated optimal parameters. As a result, the study arrived at the following conclusions. The vortical velocity increased and had a significant effect on the inclination of the fishway. Furthermore, as the velocity within the vorticity increased due to the narrowed vortical area, it was determined that further studies on vorticities or the determination of the design method for the decrease in vortical velocity were imperative.

• Journal of Korea Water Resources Association
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• v.55 no.1
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• pp.33-42
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• 2022

In this study, flow patterns in the ice-harbor fishway were analyzed according to fluctuations of the upstream water level, an increase of weir interval, and the presence or absence of orifices using a three-dimensional commercial numerical model, Flow-3D. In order to prove the suitability of the numerical simulation results, the flow velocity and flow rate at the exit of the fishway were observed using a 3D ultrasonic velocimetry on an actual ice-harbor fishway installed downstream of the Daegok bridge in Gyeongan-Cheon. Four types of turbulence modules can be selected for the Flow-3D model. As a result of verification with observation data, the RNG model best described the flow characteristics in the ice-harbor fishway. The velocity structure in the fishway according to fluctuations of the upstream water level was simulated. The results showed that the plunging flow and the streaming flow were mixed at the lowest water level. When the water level increased about 10 cm or more from the lowest water level, the plunging flow disappeared in all pools and only the streaming flow occurred. Contrary to expectations, even when the water level is rose a little, the flow simply occurred mainly on the streaming flow. If the interval between the weirs is increased, both the plunging flow and the streaming flow are showed continued even if the water level rises. In addition, compared to the case where there are no orifices at the bottom of the weirs, the plunging flow tends to be generated in several pools. It is necessary to prevent blocking orifices through active management so that various flow patterns in the fishway can be generated in multiple pools.

• Journal of computational fluids engineering
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• v.20 no.3
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• pp.15-19
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• 2015

A fishway is a structure on or around artificial and natural barriers, such as dams, locks and waterfalls, to help fishes' natural migration. In this paper, a computational fluid dynamics (CFD) code, termed SNUFOAM is used to analyze vertical hydraulic characteristic of rollway of fishway. Volume-of-fluid (VOF) method was used to handle free-surface. It is important to determine the factors influencing flow characteristics in fishway because fish use directional information from the flow characteristics to navigate through fishway. Fishway was modeled in 2-D and the influence of the stream velocity, slope, and weir height of fishway was tested. In results, the transition Reynolds number was $2{\times}10^5{\sim}3{\times}10^5$.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2003.10a
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• pp.635-638
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• 2003

This study was studied in Tamjin liver that is situated jangheung-gun Jeollanm-do. Fishways that was studied with the emphasis on Ice harbour type fishway analyzed efficiencies. In result, Ice harbor type fishway discovered 12species of fish among 13species in Tamjin liver. But, most other fishways have discovered a few fishes. Because most fishways established ill station and managed badly.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.5
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• pp.1841-1850
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• 2013

The various types of fishways are installed at the multi-functional weirs in the four major rivers to minimize the negative effect due to the construction of the transverse structures. The movable weir was installed at the upstream of the ice-harbor type artificial fishway of the Dalseong weir in the Nakdong river, which can control the fishway flowrate regardless of the river flowrate. The incoming flowrate to the artificial fishway is closely related with the hydraulic characteristics that dominate the fish passage efficiency. Thus, it is crucial to find out the weir operation rule for properly sustaining efficient fish-passage, such as the optimized flowrate. In this study, the FLOW-3D was used to analyze and compare the various hydraulic characteristics associated with the passage efficiency, based upon the given different flowrate, and subsequently provide the optimized flowrate for the fishway movable weir to maintain the best efficient flow condition for the fish-passage.

• Korean Journal of Environmental Biology
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• v.33 no.1
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• pp.75-82
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• 2015

To overcome the stream fragmentation and blockage of migration of fishes by dams and weirs, fishways are commonly installed. However, limited studies were conducted for effectiveness and suitability of fishways installed in Korean streams. In this study, we investigated fish usages (by time periods, locations and months) of the Ice Harbor type fishway installed in the Gongju weir using traps. The monitoring were monthly conducted from June to October, 2012. The number of individuals which used fishway in September and October decreased than in June to August. Although no statistical significance was identified, many numbers of species and individuals were occurred at the trap installed at the left end of fishway than others. Fishes of more diverse size classes occurred at this trap as well. The number of collected individuals and water level of weir were positively correlated though they showed low correlation coefficient. Conversely, occurrence rate of fishes smaller than 70 mm of total length decreased with increasing water level of weir. fishway usage time of fish were different depends on ecological characteristics of each species. Various sizes of fishes can use fishway for their upstream migration. These results are useful for establishing management and evaluation plans of Ice Harbor type fishway in S. Korea.

• Proceeding of EDISON Challenge
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• 2015.03a
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• pp.618-622
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• 2015

어도(fishway)란 강이 댐과 같은 인공물로 막혀있을 때 물고기가 지나갈 수 있도록 만든 통로이다. 본 연구에서는 전산유체해석 프로그램인 EDISON_CFD 시스템을 활용하여 아이스하버식 어도 내 월류부(rollway)에서 유체의 수직흐름특성을 분석하였다. 어류는 소상과 강하시 어도 내의 흐름에 민감하므로, 흐름에 영향을 주는 요인을 분석하는 것은 중요한 문제이다 어도는 2차원으로 간략화하여 모델링하였으며, 강의 유속, 어도의 기울기, 월류부 높이를 변화시키며 이들이 어도 내의 흐름특성과 어떤 관계가 있는지 분석하였다. 또 속도 증가에 따른 수면파의 파장 변화를 프로우드수와 연관지어 설명하였고, 레이놀즈수가 어도 내의 흐름특성과 밀접한 관련이 있음을 확인하였으며 기 설치된 어도의 문제점을 보완할 수 있는 방법을 제시하였다.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.19 no.4
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• pp.61-79
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• 2016

This study aims at examining the structural and managemental problems of the existing fishways which affect the migrations of fishes, and at suggesting alternatives to improve the fishways' efficiency. The study focuses on the fishways constructed in the diversion weirs in the lower reaches of 41 rivers(2 national rivers and 39 rural rivers) in the eastern coast of Korea. Most of water-using facilities in Korean rivers are diversion weirs, and fishways are established as subsidiary facilities of most of the weirs. Among the 58 or so fishways examined in this study, only a few are doing their proper function, and most of them need improvement. This study aims at strengthening those fishways function and increasing their economic efficiency and migration efficiency. Based on the results of this study, the followings are suggested. In case the fishway sticks out downstream from the apron, a subsidiary fishway diverging from the main is suggested to attract fish. The entrance to the subsidiary should head below the raised part of the apron and a pool should be constructed in the connecting part with the main. To attract fish and let the upstream migrators rest for a while, an entrance pool should be constructed in the fishway. Most of the examined fishways have low side walls, which allow the upstreamers to jump out of the fishway. Those side walls are suggested to be raised above the jumping height of target fishes. The exit parts of most fishways are too shallow, or have no grass to protect the fish from the birds. Protective facilities are suggested to keep the birds from entering the fishway. By the time Ice-harbor type and Vertical-slot type fishways are scientifically proved to be defective, the fishway should not diverge from the standard design.

• Journal of Korea Water Resources Association
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• v.52 no.spc2
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• pp.855-863
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• 2019

The efficiency of fishway installed in rivers can be directly evaluated by means of fish monitoring. On the other hand, when it is difficult to monitor the fish in certain conditions, or when planning a fishway, the efficiency can be evaluated indirectly through the hydraulic analysis. In this study, the hydraulic analysis technique for evaluating the efficiency of a fishway was presented. The River-2D model with the fish physical habitat module was used for the analysis of the attraction efficiency, and the weighted usable area was proposed as an index of the efficiency. In the analysis of passage efficiency, the three-dimensional model, Flow-3D, was used as an evaluation tool to describe the fluid behavior on a hydraulic structure with free surface. The ice-harbor type fishway at Baekgok weir in the Deokcheon River was selected as a test-site, and the efficiency was estimated using the hydraulic analysis. And then it was compared with fish monitoring data acquired from the river. As a result, it is difficult to replace the hydraulic analysis results with the efficiency quantitatively, but it can help to grasp the general tendency.

• Korean Journal of Environmental Biology
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• v.38 no.1
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• pp.30-39
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• 2020

The changes in fish stock and biomass before and after fishway renovation located in a Korean estuary were studied and fluctuations in the economic value of the fish resources were estimated. The target fishway located in the east coast area in Korea was renovated in 2014 from the small fish ladder to the ice-harbor fishway. Monitoring was continued for five consecutive years after the renovation(2015 to 2019). Since the renovation of the fish passage, the economic values increased with increases in the fishery resources, except for in 2016 when the drought impact was severe. The yearly average incremental increase in the five years after the renovation was about 227%. The increase in economic value is believed to be due to the increased population of migratory fish as a result of habitat expansion. The exponential rise model showed an increase in economic value with increasing fishery resources (R²=0.896). The model coefficient contributing to economic analysis was 0.582 and the maximum economic value after the renovation was estimated at about 30.4 million. The economic value would be a useful index for quantitative comparison in terms of ecosystem services before and after renovation.