• The Journal of Engineering Geology
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• v.3 no.2
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• pp.101-114
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• 1993

GIS technique was applied to identify the regional hydrologic units for groundwater exploitation and recharge analysis in a study area. The technique was very effective to identify the potential areas for groundwater exploitation, and for groundwater management & land use planning. GIS database of environmental resources was complied from a variety of sources and scales as the foundation for analysis, including digitizing and scanning of hardcopy maps. A DEM(Digital Elevation Model) was used to dassify slopes, and identify problematic drainage system. Quantitative analysis of environmental resources helps us to develop the scoring system of GIS model, which evaluates each resource in relation to the others and reflects the relative importance of each resource. ARC4NFO was used to construct digital database, and the cartographic simulation techniques were applied in order to create new maps.

• Proceedings of the Korea Contents Association Conference
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• 2007.11a
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• pp.937-941
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• 2007

For Hydrologic analysis of the river, the exact Dividing Watershed and Hydrologic-Topographical Parameters affect enormously Hydrologic analysis of the river basin. Therefore the extraction of Hydrologic-Topographical Parameters as well as Dividing Watershed are stiuied by several ways. However the definite standard of all those means are not settled. Recently GIS is applied to the field of water resources so that we can divide Watershed and calculate Hydrologic-Topographical Parameters of the targeted area easily and objective way for using DEM. Thanks to DEM, we don't have to spend much time as we did before. However other problems are generated such as the parameter value is changed by the precision of established NGIS(National Geographic Information System), etc. In this study, using GIS which is popular recently, we suggested efficient extract method of Hydrologic-Topographical Parameters SCS(Soil Conservation Service) CN(Curve Number) in watershed.

• Journal of Korean Society of Rural Planning
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• v.9 no.1 s.18
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• pp.85-93
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• 2003

Many features of the Single Field version have been enhanced to provide user friendly interface. The County/Watershed version of NAPRA WWW system was further enhanced. The newly developed Web GIS version is an ideal tool for novice users, such as farmers, to simulate the effects of agricultural management for their farms because of its easy-to-use Web GIS interface. The NAPRA WWW system provides an easy to use WWW interface and uses spatial and relational databases to simplify the process of preparing model files. Thus, the NAPRA WWW systems now can be effectively used for nutrient management as well as pesticide management to identify the least impact agricultural management practices.

• Journal of the Korean Society of Groundwater Environment
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• v.6 no.3
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• pp.133-139
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• 1999

The geostatistical method Kriging is used to estimate the areal distributions of the depth to the water table and the altitude of the water table measured from the sea level. A northern part of the city of Pohang, Kyeong-Buk, Korea has been chosen and the digital map of the area with 1:5,000 scale from the National Geographic Information System (NGIS) project by National Geographic Institute has bun used to reproduce the ground surface distribution. The water table depth appears to be in the range between 7 m and 9.5 m except a few localities where mountain tops exist and the use of groundwater for agicultural purposes is believed to be heavy. The overall distribution of the water table altitude shows a monotonic gradual decrease from the west to the east (seaward direction from the inland) and to the south with maximum rate approximately at 90 m over 6 km in horizontal distance and indicates that the groundwater is moving several meters per day there.

• Journal of Mushroom
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• v.18 no.1
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• pp.1-9
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• 2020

Mycorrhiza refers to the association between a plant and a fungus colonizing the cortical tissue of the plant's roots during periods of active plant growth. The benefits afforded by plants from mycorrhizal symbioses can be characterized either agronomically, based on increased growth and yield, or ecologically, based on improved fitness (i.e., reproductive ability). In either case, the benefit accrues primarily because mycorrhizal fungi form a critical linkage between plant roots and the soil. The soilborne or extramatrical hyphae take up nutrients from the soil solution and transport them to the root. This mycorrhizae-mediated mechanism increases the effective absorptive surface area of the plant. There are seven major types of mycorrhizae along with mycoheterotrophy: endomycorrhizae (arbuscular mycorrhizae, AM), ectomycorrhizae (EM), ectendomycorrhizae, monotropoid, arbutoid, orchid, and ericoid. Endomycorrhizal fungi form arbuscules or highly branched structures within root cortical cells, giving rise to arbuscular mycorrhiza, which may produce extensive extramatrical hyphae and significantly increase phosphorus inflow rates in the plants they colonize. Ectomycorrhizal fungi may produce large quantities of hyphae on the root and in the soil; these hyphae play a role in absorption and translocation of inorganic nutrients and water, and also release nutrients from litter layers by producing enzymes involved in mineralization of organic matters. Over 4,000 fungal species, primarily belonging to Basidiomycotina and to a lesser extent Ascomycotina, are able to form ectomycorrhizae. Many of these fungi produce various mushrooms on the forest floor that are traded at a high price. In this paper, we discuss the benefits, nutrient cycles, and artificial cultivation of mycorrhizae in Korea.

• Spatial Information Research
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• v.8 no.2
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• pp.301-315
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• 2000

Every, year, a great amount of site investigation data is collected on site to obtain sufficient conditions. Investigation of subsurface conditions is prerequisite to the design and construction of structures and also provides information on ground properties such as geologic formation and types of soil. This data set, which portrays real representation of ground conditions over the existing geologic and soil maps, could be further utilized for analyzing the subsurface conditions. It is therefore necessary to develope a subsurface exploration analysis system which is able to extract the valuable information from the heterogeneous, non-normalized subsurface investigation data. This paper presents the overall design scheme and implementation on a subsurface exploration analysis system. The analysis system employs one of data set such as bore-hole data. The clustering technique employed in the developed system makes a large volume of bore-hole data into several groups in terms of ground formation and geographical vicinity. As a result of clustering, each group or cluster consists of bore-hole data with similar characteristics of subsurface and geographical vicinity. In addition, each clustered data is displayed on digital topographical map with different color so that the analysis of site investigation data could be performed in more sensible ways.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.1607-1611
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• 2009

본 연구에서는 현재 가뭄을 관측하는데 주로 이용되는 가뭄지수의 단점 등을 보완하고자 가뭄에 관련되는 식생지수를 연계한 공간해상도 높은 가뭄지수를 제시하였다. 우리나라 지상관측을 통해 산출할 수 있는 PDSI(Palmer Drought Severity Index)와 SPI(Standardized Precipitation Index) 같은 가뭄지수는 기온과 강수량 등의 기후자료만을 이용하여 산정할 수 있다. 두 가뭄지수는 관측하기 어려운 가뭄의 시기와 심도를 설명하고자 여러 연구를 통해 개발한 지수이지만, 두 가뭄지수만을 가지고 우리나라 전역의 가뭄의 공간적인 분포를 설명하기에는 다소 무리가 있다. PDSI의 경우 강수량과 기온과 토양의 수분함유량을 가지고 산출하는데, 전 관측지점을 똑같은 토양수분함유량을 가지고 있다는 가정 하에 계산되고, SPI의 경우 강수량만을 이용하여 산정한다. PDSI의 경우 과거의 가뭄의 정도를 판단하는데 매우유용하다고 알려져 있다. 하지만, 현재의 가뭄정도를 나타내는 데는 문제를 가지고 있고, SPI의 경우는 누적강수량을 가지고 시간단위로 계산한다는 점에서 다양한 가뭄의 정도를 예측할 수 있지만, 입력 자료로 강수량만 들어간다는 점에서 약점을 가진다. 이런 기후지수만을 이용한 가뭄정보 생산이 공간정보를 구현하는데 한계를 가지는 문제점을 개선하고자 가뭄에 직간접적으로 관련이 있는 보다 세밀한 공간정보를 가진 식생, 토지이용, 고도 등의 자료와 기후정보로부터 산정된 가뭄지수간의 관계를 분석하였다. 나아가 기존의 기후지수보다 고해상도를 가진 위성의 정규식생지수(NDVI; Normalized Difference Vegetation Index)와 같은 식생지수를 이용하여 기존보다 더 향상된 해상도의 가뭄지수를 산정하고자 하였다. 우리나라 지상관측소 76개 지점 중에 MODIS(Moderate Resolution Imaging Spectroradiometer) 정규식생지수 자료와의 관계를 분석하고자 자료의 보유기간이 짧은 지점과 섬지점 등을 제외한 57개 지점을 선정하고, 연구기간동안의 강수량과 기온자료를 이용하여 PDSI와 SPI를 산출하였다. PDSI와 SPI자료를 고해상도 가뭄지수 산정의 기본 변수로 사용하기 위하여 역거리가중평균법을 이용한 연구기간동안의 한반도 지역 PDSI와 SPI 가뭄지수 지도를 생산하였다. 각각의 가뭄지수와 식생 상태를 나타내는 NDVI와의 상관특성과 계절 변화에 따른 변화특성을 분석하고, CART(Classification and Regression Trees) 알고리즘을 이용하여, 지상 자료만을 사용한 가뭄지수가 가지는 시공간적 변화 특성 제시에 대한 문제점을 개선한 보다 해상도가 높은 조합가뭄지수를 제시하였다.

• Journal of the Korean Society of Groundwater Environment
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• v.3 no.2
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• pp.101-109
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• 1996

DRASTIC system was used in this study that was developed by U.S. EPA and is widely used for evaluating relative groundwater pollution potential by using hydrogeological factors. The DRASTIC system can be used for selection of well sites, selection of waste disposal sites and basic data of landuse for groundwater protection, and monitoring purpose and efficient allocation of resource for remediation. This study analyzed regional groundwater pollution potential around Chungju Lake using the DRASTIC system. Hydrogeological factors used in this study are depth to water, net recharge, aquifer media, soil media, slope and hydraulic conductivity. For accurate analysis, lineament density that is extracted from image processing of satellite image is overlaid to the DRASTIC system. Results of this study are mapped so groundwater pollution potential and risk degrees can be understood easily and quickly. A graphic user interface is developed to process the data conveniently.

• The Korean Journal of Mycology
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• v.44 no.1
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• pp.16-22
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• 2016

Five islands (Sinjindo, Mado, Daenanjido, Wonsando, and Sapsido) and the coastal area (Muchangpo) in Chungnam, Korea, were selected to determine the diversity of arbuscular mycorrhizal (AM) fungi. Soil-inhabiting AM fungi were isolated and identified on the basis of morphological characteristics and sequence analyses of 18s rDNA. The differences in the fungal community structures were compared among sites. As a result, 24 species of AM fungi were identified, of which two species of AM fungi, Acaulospora brasiliensis and Redeckera fulvum, were isolated for the first time in Korea. This study revealed that AM fungal spore abundance was low and the genus Acaulospora was dominant in most of the islands. AM fungal community structures in five Islands were highly similar. However, the coastal area, Muchangpo, had different AM fungal community structure from the islands.

• Journal of Korean Society for Geospatial Information Science
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• v.17 no.2
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• pp.61-69
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• 2009

In mid-July, 2006 the torrential rainfall across Gangwon-do region caused 48 casualties and 1,248 houses submerged, resulting in damages with the restoration costs of 3 trillion and 512.5 billion won. This was because the topographic characteristics of Gangwon-do region for which mountainous areas mostly account increased the effects of landslide. In this study, the landslide region was shot using the PKNU No.4 system immediately after the occurrence of landslide in order to analyze it as objectively, exactly, and rapidly as possible. 1,054 areas with landslide occurrence were extracted by digitizing the shot images through visual reading after orthometric correction using ERDAS 9.1. Using the Arc GIS 9.2, a GIS program, hydrologic, topographic, clinical, geologic, pedologic aspects and characteristics of the landslide region were established in database through overlay analysis of digital map, vegetation map, geologic map, and soil map, and the status and characteristics of the occurrence of the landslide were analyzed.