• Journal of Korean Society of Forest Science
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• v.107 no.1
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• pp.59-70
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• 2018

The objective of this study was to develop erosion control dam for preventing disaster in consideration of characteristics of forested catchment near urban area, and to assess its stability and functionality to see its practicability in the field. Two types of hybrid erosion control dams were developed including debris flow prevention dam by using pillar and float board screen type and debris flow control dam by using groyne. Also, review about their static (sliding, overturning, bearing capacity) and dynamic (member force) stability was carried out. According to the result, most of the assessed items met standard safety level although there were some cases where assessed items were short of stability criteria against impact. Also, after miniature flume experiments based on the developed erosion control dam to prove structure function (material catch, deposit), it turned out the dam decreased flow sediment amount and velocity while increasing sediment-capturing capacity by 3.5 times on average compared to the one controlled without erosion control dam. When function of erosion control dam for forested catchment near urban area is quantified based on future flume experiments in a variety of conditions, the dams can be practically used in the urban area, contribution to effectively reducing debris flow damage.

• Journal of Korean Society of Forest Science
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• v.101 no.3
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• pp.412-425
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• 2012

Concrete Soil Erosion Control Dam, which blocks flow of debris flow in torrential stream, are reported to lose expected functions due to structural failure and collapses, caused by poor construction, material deterioration and external impacts. In this paper, an integrity assessment technique for debris barriers was proposed, which allows preliminary detection of problems inherent in debris barriers. The proposed integrity assessment technique is a non-destructive method based on SASW method, one of surface-wave tests. In this paper, a practical procedure and analysis guidelines in applying the SASW technique to debris barrier was proposed and its validity was verified using five decrepit debris barriers older than 20-year old. As a result, the SASW method was validated for the reliable grade evaluation method for concrete soil erosion control dam, and the resulting grades turned out to agree with the results determined by Sabang Associations.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.39 no.6
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• pp.725-733
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• 2019

Sand dams are structures that can be used as auxiliary water resources in case of drought as sand accumulates due to barriers crossing valley rivers and valley water is stored in the voids, increasing the water level. This structure, which is mainly used in arid regions such as Africa, has not been installed in Korea. In Korea, there are only a few cases where water is taken from debris barriers that prevent debris flow. The purpose of this study is to evaluate the effect of water supply when the sand dam is installed downstream of the existing intake barrier in Seosang-ri valley, Chuncheon. For this purpose, modeling was performed by linking the basin hydrologic model and reservoir routing model. Changes in the water level, storage and discharge in the sand dam reservoir according to the size and intake of the sand dam are presented on a case-by-case basis. As a result of application, it was found that the water supply capacity due to the sand dam installation was improved at 95% reliability. Especially, when the size is L × B × H_o = 25 m × 15 m × 1 m and the pumping rates from intake barrier and sand dam are (Q₁, Q₂) = (30, 20), (35, 15) ㎥/day, the efficiency was the best for water supply of 50 ㎥/day.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.592-599
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• 2004

Talus topography is that weathered rock clasts were accumulated dropping in steep slope to action of gravity. Rock fall talus is formed by the accumulation of rock debris falling as individual particles from a cliff. If the collapse is produced in talus slope. it will be possible the loss of manpower and country. Despite correct access about talus is required, domestic research was scientific access about talus short because of short resolution of aerophoto and difficulties of research about huge talus. In this Study, Our research team analgize the wetness index using the geomorphogical data. Lineament through wetness index is simillar with distribution of the talus. And, the aim of the present study is to review and compare fabric data derived from rock fall talus about orientation, distribution and morphology. These deposits tend to have approximately equal amounts of clasts oriented parallel and perpendicular to the dip direction of the slope. And, platy- shaped clasts dominate the proximal and intermediate parts of the talus, wheres blocky-shaped clasts is more common in the distal part. we carry out Rock Fall Simulation. And, We install criteria of the rockfall protective barrier using talus and geomorphological characteristics.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.752-757
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• 2009

In the last decade, many methods such as greet chamber, reservoir, or debris barrier, have been utilized to manage and prevent muddy water problem. The Vegetative Filter Strip (VFS) has been thought to be one of the most effective methods to trap sediment effectively. The VFS are usually installed at the edge of agricultural areas adjacent to stream or drainage ditches, and it has been shown that the VFS effectively removes pollutants transported with upland runoff. But, if the VFS is installed without any scientific analysis of rainfall-runoff characteristics, soil erosion, and sediment analysis, it may not reduce the sediment as much as expected. Although Soil and Water Assessment Tool (SWAT) model has been used worldwide for many hydrologic and Non-Point Source Pollution (NPSP) analysis at a watershed scale. but it has many limitations in simulating the VFS. Because it considers only 'filter strip width' when the model estimates sediment trapping efficiency, and does not consider the routing of sediment with overland flow option which is expected to maximize the sediment trapping efficiency from upper agricultural subbasin to lower spatially-explicit filter strip. Therefore, the SWAT overland flow option between landuse-subbasins with sediment routing capability was enhanced with modifications in SWAT watershed configuration and SWAT engine. The enhanced SWAT can simulate the sediment trapping efficiency of the VFS in the similar way as the desktop VFSMOD-w system does. Also it now can simulate the effects of overland flow from upper subbasin to reflect the increased runoff volume at the receiving subbasin, which is what is occurring at the field if no diversion channel is installed. In this study, the enhanced SWAT model was applied to small watershed located at Jaun-ri in South Korea to simulate diversion channel and spatially-explicit VFS. It was found that approximately sediment can be reduced by 31%, 65%, 68%, with diversion channel, the VFS, and the VFS with diversion channel, respectively.

• Journal of Acupuncture Research
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• v.24 no.6
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• pp.137-148
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• 2007

Objectives : Following central nervous system (CNS) injury, inhibitory influences at the site of axonal damage occur. Glial cells become reactive and form a glial scar, know as gliosis. As well,myelin debris such as MAG inhibits axonal regeneration. Astrocyte-rich gliosis relates to up-regulation of GFAP and CD81, and eventually becomes a physical and mechanical barrier to axonal regeneration. It is postulated that when the astrocytic reaction is absent, regeneration of axons can occur. It was reported that treatment with anti CD81 antibodies enhanced functional recovery in rats with spinal cord injury. Methods : MAG is one of several endogenous axon regeneration inhibitors that limit recovery from central nervous system injury and disease. It was reported that molecules which block such inhibitors enhanced axon regeneration and functional recovery. Results : In this current study, the author investigated the effect of the water extract of Ginseng Radix on the regulation of CD81, GFAP and MAG which increases when gliosis occurs. MTT analysis was performed to examine cell viability, and cell based ELISA, Western Blot and PCR were used to detect the expression of CD81, GFAP and MAG. Immunohistochemistry was also performed to confirm in vivo. Conclusions : We observed that Ginseng Radix significantly down-regulates the expression of CD81, GFAP and MAG by means of cell based ELISA, Western Blot and PCR. In immunohistochemistry, expression of CD81, GFAP and MAG also decreased. Taken together, these results suggest that Ginseng Radix can be a candidate for regenerating CNS injury.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.170-174
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• 2011

홍수시 저수지 상류로부터 유입되는 다량의 오염물, 협잡물은 저수지의 경관 및 수질에 악영향을 미친다. 이러한 오염물질은 홍수시 일시에 유입되어 표층에 부유하므로 수거를 위한 시간 및 비용이 비교적 크게 발생된다. 따라서 이러한 부유쓰레기를 효과적으로 차단할 수 있는 시설물 설치는 필연적이다. 이렇게 부유쓰레기 수거를 위한 방법 중, 저수지 내부에 선 차단 시설을 설치하여 부유쓰레기를 홍수터로 유도하여 수거하는 방법은 일시에 많은 양의 부유쓰레기를 차단하게 되는데 유지관리, 경제적 측면에서 유리하다. 본 연구에서는 부유쓰레기 수거를 위한 선 차단시설 운영 방안을 검토하기 위하여 홍수시 저수지 내로 유입되는 유속흐름을 2차원 수치해석 모형인 RMA-2 모형으로 해석하고, 저수지의 내 외부 지형분석을 통하여 시범 지구의 선 차단시설 설치 위치를 선정하였고, 3차원 수치해석 모형인 FLOW-3D 모형으로 검증하였다. 선 차단시설 설치 시범지역 위치 선정을 위하여 저수지의 규모, 접근성, 시공 장비의 대여 편이성 등을 종합적으로 고려하여 기흥저수지를 시범예정 구역으로 선정하였다. 저수지 내로 유입되는 유속특성을 2차원 수치해석 모형인 RMA-2 모형으로 해석하여 시범 지구의 선 차단시설 설치 위치를 제안하고 홍수터 부지를 결정하였다. 부유쓰레기 유도를 위한 선차단시설은 저수지 급확대로 인한 유속 감소구간과 와류발생 구간이 적절한 것으로 분석되었으며 시범설치 지역인 기흥저수지 상류 급확대부에 선 차단시설을 제안하였다. 홍수터의 규모는 Armitage와 Rooseboom(2000)이 제안한 경험식을 바탕으로 $5,300m^2$을 제안하였으며, 기흥저수지 상류부 우안에 항아리 모양으로 설치하도록 계획하였다. 또한, 3차원 수치모형실험을 통하여 검토한 결과, 차단막 설치로 부유 쓰레기의 하류 이송은 차단되고, 원활하게 홍수터로 유도됨을 확인하였다.

• Journal of Pharmacopuncture
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• v.12 no.1
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• pp.67-76
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• 2009

Objective : Following central nervous system(CNS) injury, inhibitory influences at the site of axonal damage occur. Glial cells become reactive and form a glial scar, gliosis. Also myelin debris such as MAG inhibits axonal regeneration. Astrocyte-rich gliosis relates with up-regulation of GFAP and CD81, and eventually becomes physical and mechanical barrier to axonal regeneration. MAG is one of several endogenous axon regeneration inhibitors that limit recovery from CNS injury and disease. It was reported that molecules that block such inhibitors enhanced axon regeneration and functional recovery. Recently it was reported that treatment with anti-CD81 antibodies enhanced functional recovery in the rat with spinal cord injury. So in this current study, the author investigated the effect of the water extract of Uncariae Ramulus et Uncus on the regulation of CD81, GFAP and MAG that increase when gliosis occurs. Methods : MTT assay was performed to examine cell viability, and cell-based ELISA, western blot and PCR were used to detect the expression of CD81, GFAP and MAG. Then also immunohistochemistry was performed to confirm in vivo. Results : Water extract of Uncariae Ramulus et Uncus showed relatively high cell viability at the concentration of 0.05%, 0.1% and 0.5%. The expression of CD81, GFAP and MAG in astrocytes was decreased after the administration of Uncariae Ramulus et Uncus water extract. These results was confirmed in the brain sections following cortical stab injury by immunohistochemistry. Conclusion : The authors observed that Uncariae Ramulus et Uncus significantly down-regulates the expression of CD81, GFAP and MAG. These results suggest that Uncariae Ramulus et Uncus can be a candidate to regenerate CNS injury.

• Journal of Korean Society of Forest Science
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• v.100 no.3
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• pp.483-493
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• 2011

Erosion control dams play a primary role in preventing or controlling natural disasters (landslide and debris flow etc.) and also conserve ecosystem in forested watersheds. This study examines structural characteristics of the dams such as the height of ecosystem control and the ecosystem permeability of the erosion control dams under standard drawings and the existing construction works. The objective of this study was to characterize the type classification of erosion control dams as ecosystem. Average permeability was highest on eco-piller dam (63.0%), followed in increasing order by wire rope (13.9%), silt dam (10.9%), multifunctional dam (7.2%), and gravity dam (0.4%). The height of ecosystem control was highest on gravity dam (3.2 m), followed in increasing order by multifunctional dam (1.7 m), wire rope dam (1.2 m), silt dam (0.6 m), and eco-piller dam (0.0 m). Criteria for defining the height of ecosystem control was indefinite. We grouped erosion control dams into three functional types (eco-connection, eco-semi connection, and eco-disconnection) by considering physical and structural characteristics such as the ecosystem permeability and the height of ecosystem control. The type of eco-connection (permeability > 20%) had connection areas from streambed to adjacent riparian areas, and these connection areas serve as ecosystem corridors for fauna and flora. Typical wildlife species includes mammals, reptiles, amphibians, and fishes. The type of eco-semi connection (5% < permeability < 20%) had < 2 m in the eco-barrier height from streambed, however, this type of dams partially serve as wildlife corridors and often provide fish ways. The type of eco-disconnection (permeability < 5%) had > 2 m in the eco-barrier height from streambed, thereby preventing wildlife movement.