• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.667-676
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• 2005

In this research, the reasonable local scour estimates considered conditions of the bed material and the flow was accomplished on two piers P14 and P17 of Il-san bridge. Especially, the Il-san bridge was located on the lower Han-river where is influenced by the tides of In-chon, and it has hydraulic condition that can cause the bridge piers local scour because of tides at ordinary times, as well as a flood. Therefore, the local scour depth has been presented influenced by the maximum velocity of the flow when a flood after construction and the tides on construction on the basis of the standards of river design and road design, furthermore, the results was made a comparative analysis. According to the results, the local scour depth on the basis of the standards of river design was higher than it on the basis of the standards of road design(SRICOS), and the local scour depth influenced by the maximum velocity of the flow when a flood after construction was determined the final local scour depth of P14 and P17 at the Il-san bridge. It was ascertained that the local scour depth did not exceed the inserted depth of bridge foundation.

• Journal of Life Science
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• v.13 no.5
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• pp.582-589
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• 2003

The effect of useful rhizobacterium added in bed soil on the early growth promotion of red pepper plug seedlings was investigated. Total 540 colonies of rhizobacteria from 385 samples of eggplant family roots were isolated. Among these, 5 isolates were selected for antifungal activity against pathogenic fungi such as Alternaria solani, Botrytis cinerea, Fusarium oxysporium, Phytophthora capsici, and Sclerotia sclerotiorum. Of all the isolates, MJ-3 having the most pronounced growth-promoting ability for red pepper was finally selected and identified as Bacillus amyloliquefaciens through characterization of biochemical and bacteriological aspects and 16S rDNA sequence. The plant height, stem diameter, root length and fresh weight of red pepper plants which were grown with inoculation of B. amyloliquefaciens MJ-3 were higher than those without inoculation. Especially the root weight of the inoculated red pepper plant increased by 44.3%, the content of endogenous plant hormone (CA$_1$) being 0.556 ng/g (dry weight).

• Proceedings of the Plant Resources Society of Korea Conference
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• 2010.05a
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• pp.11-11
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• 2010

패모(貝母)는 땅속의 뿌리줄기에 있는 2매의 비늘조각(인편(鱗片))이 마치 조개처럼 합쳐 있어 패모라 불리우며, 백합과로 숙근성 다년생 초본의 절패모(浙貝母; Fritillaria thungergii) 및 동속식물의 비늘줄기를 기원으로 하며, 중국의 강소 절강 안휘 등지에서 대량으로 재배되고 있다. 패모의 줄기는 15~40cm정도로 곧게 자라며, 꽃은 4~5월에 피며, 윗부분의 엽액에 1개씩 밑을 향하여 달린다. 종자는 결실률이 매우 낮아 이용을 할 수 없어 번식은 대부분 비늘줄기의 인편이나 자구를 이용한다. 약용부위는 인경(鱗莖)(비늘줄기)이 사용되는데, 인경(鱗莖)에는 알칼로이드물질인 verticine, fritillin, peimisine, peimine 등의 주요 성분을 함유하여 약리작용으로는 중추신경마비, 혈압강하 및 진해작용이 있다. 한방에서는 진해, 거담, 배농, 폐렴, 기관지염 등으로 이용하는 중요한 약초 중의 하나이나, 값싼 중국산 패모의 수입으로 우리나라에서는 재배가 붕괴되어 현재는 재배면적이 거의 없는 자원고갈 약초로 재배면적 확보가 시급한 실정에 있어 이를 되살리기 위한 노력이 절실한 실정이다. 따라서 패모 자구 증식을 위하여 온도와 $GA_3$, 상토의 조건에 따른 시험을 수행한 결과 패모 자구의 증식 효과는 저장온도 온도가 낮을수록 자구의 증식이 많아 $5^{\circ}C$에서 주당 5.5개로 구수의 증식효과가 높았으며, 상토는 모래와 밭흙에서 각각 3.1개, 2.5개로 많았으나, $GA_3$과 온탕처리에 있어서는 차이가 없었다.

• Journal of Korean Society for Atmospheric Environment
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• v.24 no.5
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• pp.538-550
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• 2008

Radon is an invisible, odorless, and radioactive gas. It is formed by the disintegration of radium, which is a decay product of uranium. Some amounts of radon gas and its products are present ubiquitously in the soil, water, and air. Particularly high radon levels occur in regions of high uranium content. Although radon is permeable into indoor environment not only through geological features (bed rock and permeability) but also through the construction materials and underground water, the radiation from the geological features is generally main exposure factor. So there can be a problem in a certain space such as the underground and/or relatively poor ventilation condition. In this study, a GIS technique was used in order to investigate spatial distribution of radon measured from sub- way stations of 1 thru 8 in Seoul, Korea in 1991, 1998, 2001, and 2006. Spatial analysis was applied to reproduce the radon distribution. We utilized spatial analysis techniques such as inverse distance weighted averaging (IDW) and kriging techniques which are widely used to relate between different spatial points. To validate the results from the analyses, the jackknife technique for an uncertainty test was performed. When the number of measuring sites was less than 100 and also when the number of omitted sites increased, the kriging technique was better than IDW. On the other hand, when the number of sites was over 100, IDW technique was better than kriging technique. Thus the selection of analytical tool was affected sensitives by the analysis based on the number of measuring sites.

• Resources Recycling
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• v.27 no.3
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• pp.39-47
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• 2018

According to Vietnam government establishes additional coal-fired power plants to secure generation capacity, emission of ashes is accelerating and processing them is urgent issue. This study targeted utilize fly ashes that occurred in circulating fluidized bed combusion (CFBC) power plant to use ground solidification materials. CFBC fly ashes are used to make solidification with ground granulated blast furnace slag (GGBFS), gypsum and cement. Then produced specimens by mixing with soft ground soil to confirm mixing effect of fly ash in solidification. As a result it was possible to find mixture design that is satisfied 3 MPa compressive strength in age 28 days and reduce weight loss rate over 50% in acid immersion test than plain specimens that using only ordinary portland cement.

• Economic and Environmental Geology
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• v.41 no.1
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• pp.57-62
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• 2008

The application of constructed subsurface-flow wetlands for treatment of wastewater from abandoned mines is being increased. Crushed limestone, oak chips, and mushroom composites are often employed in a bulk form, as the substrates in the bed media. Efficiency of the subsurface-flow treatment system drops with time as the hydraulic conductivity of the wetland soil decreases significantly, presumably due to chemical reactions with the wastewater. The purpose of this study is to investigate the applicability of immobilized beads carrying sulfate reducing bacteria for acid mine drainage treatment system. The ingredients of immobilized beads are organic materials such as mushroom composite and oak chips, limestone powder for a pH buffer, mixed with a modified Coleville Synthetic Brine. It was found that immobilized beads are more efficient than the bulk form for pH recovery, sulfate and heavy metal removal.

• Journal of Wetlands Research
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• v.14 no.2
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• pp.277-288
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• 2012

Estuary is unique habitat ground under substantial changes of water quality, river side, bed material, and micro topography. Construction of SinGok underwater weir with excessive dredging for downstream of weir has changed hydraulic conditions of Han River. This study investigates spatial changes of estuary and expansion process of vegetation on sandbar for JangHang estuary in Han River through analysis of physical and ecological characteristics. As a result of investigation, we found that area of sandbar in JangHang estuary is expanded six times compared between 1985 and 2006, and area of Phragmites australis is gradually decreased while area of Salix subfragilis Anderson. is increased. Also the analysis result of soil layer shows that the Jang-Hang wetlands are created by effect from river, and woody plants are settled from middle part of wetlands, then spread to upper and lower part of wetlands.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.301-304
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• 2008

The purpose of this study is to embody the integrated working management system for public works, focused on the management of surplus soil at a field of public works. The contents and results of this study can be classified into the design of working management DB for public works and the embodiment of working management DB. First, the design of working management DB for public works consists of three DBs - process management to analyze work plan and performance. for backhoe loader, working management and resources management for equipment and labor management - in connection with work and resources classification system. Secondly, the working management system for public works can describe work plan and performance on a floor plan using graphic. Based on this, the status of process and progress report with visual expression had been developed to facilitate the communications and performance of duties among staff in charge at the field of public works. This study is a specialized system for a company specializing in public works and a system that can be put into practical use if practicality is proved through test-bed with regard to business.

• Journal of the Earthquake Engineering Society of Korea
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• v.8 no.3
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• pp.23-32
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• 2004

The local geologic and dynamic site characteristics, which include soil profiles, shear wave velocity profiles and depths to the bed rock were gathered from 148 sites all over the Korean peninsula and those values are compared to those in the western USA. Site response analyses were performed based on equivalent linear scheme using design rock-outcrop acceleration of 0.154g which corresponds to the collapse level of earthquake for seismic category I structure. The results show that the amplification factor based on Korean seismic design guideline underestimates the motion in short-period range and overestimates the motion in mid-period range. It is suggested that the existing Korean seismic guideline based on UBC is required to be modified considering dynamic site characteristics in Korea for the reliable estimation of site amplification.

• Journal of the Korean GEO-environmental Society
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• v.17 no.1
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• pp.21-28
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• 2016

This paper deals with contents on the estimation of rail beam from the geotechnical engineering aspect. Rail beam is reinforced rail installed on the inside and outside of rail to prevent differential settlement during the construction period of railroad crossing construction. Such rail beam is frequently being installed to ensure stability of existing railroad facilities because of increasing constructions of underground structures crossing railroad in recent. However, there is a difficulty in design due to lack of design standard on rail beam length. Furthermore, derailing accidents are also occurring as a result of rail beam length shortage. Accordingly, this paper presented flow chart based on the classification into soil ground and bedrock ground for the rail beam length estimation. In addition, case study was conducted on rail combination and location through which effective rail combination and location were ensured.