• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.1614-1618
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• 2007

분포형 수문모형은 유역을 격자단위로 세분화하여 매개변수를 부여하고, 증발산, 침투, 지표면유출, 중간유출, 지하수유출, 하도흐름 등 여러 가지 수문요소를 해석하는 종합적인 수문모형이다. 지표면에 내린 강우의 증발 및 침투, 유출은 토양수분의 함량에 크게 의존하게 된다. 따라서 토양수분에 대한 적절한 모의가 분포형 수문모형의 정확도를 좌우하는 핵심이라 할 수 있다. 토양수분은 식물의 생장 및 가용수자원 산정 등에 있어서 중요한 요소로서 토양층 상부의 수 미터 내에 존재하는 수분의 양을 일컫는다. 토양수분의 공간적 시간적 특성들은 증발, 침투, 지하수 재충전, 토양침식, 식생분포 등을 지배하는 매우 중요한 요소라 할 수 있다. 강우로 인한 지면과 지표하에서의 순간적인 포화공간의 형성 및 유출의 생성을 포함하는 과정과 증발산 등은 모두 비포화대(vadose zone) 혹은 토양층에서의 토양수분의 함량에 크게 의존하게 된다(이가영 등, 2005) 본 연구에서는 토양수분에 대한 정밀측정 자료가 있는 설마천 유역 범륜사 사면에 대하여 분포형 수문모형의 토양수분 해석 능력을 평가하고자 하였다. 토양수분 모의에 사용된 격자기반의 분포형 수문모형은 미공병단에서 개발한 GSSHA(USACE, 2006) 모형이다. 모형의 입력자료는 정밀토양도와 현장측정에 의한 토양매개변수를 반영하여 구축하였고, 강우 및 기상자료는 2003년 1월 1일 ${\sim}$ 2004년 12월 31일의 1시간 자료를 이용하였다. 모의기간 중 2003년은 초기 토양수분값 등 초기조건의 영향을 줄이기 위한 웜업 (Warm-up)기간으로 설정하였고, 2004년의 모의결과를 토양수분 관측값과 비교하였다.업지역, 상업지역 등과 같이 지형적 특성에 따른 유량측정망을 구축하는 것이다.의 의사결정 지원 도구가 될 것이다. 따라서, 본 연구에서는 도시유역의 물순환 해석을 위한 일련의 과정, 즉 자료의 조사 및 취득에서부터 물순환 해석 모형을 이용한 정량적 현황파악, 물순환 개선 기법 및 평가를 수행함에 있어 주요 착안점 및 실무에서의 기술적 가이드를 제공하고자 하였으며, 보다 세밀한 도시유역의 물순환 해석을 위하여 우리나라와 일본에서 적용이 활발한 물리적 기반의 분포형 모형(WEP, SHER, SWMM)의 적용사례를 통하여 국내 도시하천의 물순환 해석에 활용함에 있어서의 실질적인 적용절차 등을 제시하고자 하였다. 한다.호강유역의 급격한 수질개선을 알 수 있다.世宗實錄) $\ulcorner$지리지$\lrcorner$(地理志)와 동년대에 동일한 목적으로 찬술되었음을 알 수 있다. $\ulcorner$경상도실록지리지$\lrcorner$(慶尙道實錄地理志)에는 $\ulcorner$세종실록$\lrcorner$(世宗實錄) $\ulcorner$지리지$\lrcorner$(地理志)와의 비교를 해보면 상 중 하품의 통합 9개소가 삭제되어 있고, $\ulcorner$동국여지승람$\lrcorner$(東國與地勝覽) 에서는 자기소와 도기소의 위치가 완전히 삭제되어 있다. 이러한 현상은 첫째, 15세기 중엽 경제적 태평과 함께 백자의 수요 생산이 증가하자 군신의 변별(辨別)과 사치를 이유로 강력하게 규제하여 백자의 확대와 발전에

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.36 no.2
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• pp.59-66
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• 2018

This study examined the correlation among topography, forest type, soil and geology in Inje area where landslides occurred during heavy rainfall from July 11 to July 18, 2006 to assess the landslide susceptibility. In order to assess the susceptibility of future landslides, landslides occurred in Inje area were classified into slide type and flow type, and slope angle, aspect, curvature, ridge and valley were extracted from the area. The landslide susceptibility was assessed by applying diameter class, age class, density, and forest type to Bayesianbased LR (Logistic Regression) model and WOE (Weight of Evidence) model, and the fitness of modeling was verified by predict rate curve. As the results of susceptibility assessment, using all landslides without no distintion, it was found that 75% of the LR model and 73% of the WOE model were fit in terms of the top 20% of the landslides. According to slide type and flow type in the top 20% of the landslides, it was found that 71% of the LR model and 69% of the WOE model were fit in terms of the slide type. Whereas, it was found that 86% of the LR model and 82% of the WOE model were fit in terms of the flow type. That is, the results of the LR model showed higher fitness than the results of the WOE model, and the fitness of the flow type was higher than that of the slide type. Consequently, it suggests that it is reasonable to assess and verify the landslide susceptibility according to the types of landslides.

• Economic and Environmental Geology
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• v.43 no.4
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• pp.381-391
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• 2010

Probabilistic prediction methods of landslides which have been developed in recent can be reliable with premise of detailed survey and analysis based on deep and special knowledge. However, landslide susceptibility should also be analyzed with some reliable and simple methods by various people such as government officials and engineering geologists who do not have deep statistical knowledge at the moment of hazards. Therefore, this study suggests an evaluation chart of landslide susceptibility with high reliability drawn by accurate statistical approaches, which the chart can be understood easily and utilized for both specialists and non-specialists. The evaluation chart was developed by a quantification method based on canonical correlation analysis using the data of geology, topography, and soil property of landslides in Korea. This study analyzed field data and laboratory test results and determined influential factors and rating values of each factor. The quantification analysis result shows that slope angle has the highest significance among the factors and elevation, permeability coefficient, porosity, lithology, and dry density are important in descending order. Based on the score assigned to each evaluation factor, an evaluation chart of landslide susceptibility was developed with rating values in each class of a factor. It is possible for an analyst to identify susceptibility degree of a landslide by checking each property of an evaluation factor and calculating sum of the rating values. This result can also be used to draw landslide susceptibility maps based on GIS techniques.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.10 no.6
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• pp.130-138
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• 2007

To protect the surface of ground-cutting slopes occurring at the national road substitute detour [roundabout road]construction jobsite between Munduk and Wubokgu within the jurisdiction of Pohang-si and environment-friendly road construction, a test execution of re-vegetation measures on the major slopes was done and the results are as follows : As a result of finding out the number of sprouting individuals on the test construction site, the average number of sprouting individuals on the three test spots by the method of revegetation measures D, revegetation measures A, and revegetation measures B was 1,292 number of per square meter, 1,190 number of per square meter, and 1,095 number of per square meter respectively, which statistics were higher than those of test spot by the revegetation measures C. As a result of finding out living plant's breeding index [weight in dried state], the average dried weight of living plant at the test spot by the method of revegetation measures B, in case of foreign herbal species, was the highest marking 8.96 grams per square meter, and the next was 6.86grams per square meter by the method of revegetation measures D, and the next after was 6.80 grams per square meter by the method of revegetation measures A, and the last 5.93 grams per square meter by the method of revegetation measures C. As a result of finding out the covering degree on the slopes, the same average covering degree of 80% and 77.5% in revegetation measures A and revegetation measures D individually, which showed a somewhat higher covering degree than those of revegetation measures B and revegetation measures C. As a result of finding out appearing plants on the test construction site, seeding plant life was found to be sprouting on all test spot while native and foreign herbal species and herbaceous plant as well as shrubs were growing in good harmony with each other. However, in case of revegetation measures B and revegetation measures C method, foreign plant species are dominantly growing. As a result of inspecting rifts on the slopes and the excavated state by water, there existed cracks in some of base materials only in revegetation measures C method applied spot.

• Korean Journal of Environment and Ecology
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• v.30 no.2
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• pp.214-227
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• 2016

This study was conducted to classify the vegetation structure of the Geumsan in Namhae-gun. Using the phytosociological method and DCCA ordination, the vegetation was classified into 10 communities of natural forests (Quercus serrata, Carpinus tschonoskii, Q.mongolica, Pinus densiflora, P.thunbergii, C. turczaninowii, Q. variablis, Zelkova serrata, C.laxifora and Corylopsis gotoana var. coreana) and 2 communities of plantation forests (Chamaecyparis obtusa and Cryptomeria japonica). Among the communities other than the plantation forests, the importance value of Q. serrata (45.7) was found to be the highest. According to the results of DBH analysis among the species with high importance values, Q. serrata, Q. mongolica and C. tschonoskii showed normal patterns in the size-frequency distribution, suggesting that these species will continue to hold their current dominance. The average soil pH in the communities ranged from 4.28 to 4.76. The results of DCCA ordination analysis showed that Q. serrata was evenly distributed in the high and low elevation habitats. P. thunbergii and P. densiflora communities were mainly distributed in the lowest elevation habitats on the southern slope.

• Korean Journal of Environment and Ecology
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• v.29 no.4
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• pp.605-614
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• 2015

This study was carried out to maintain, manage and restore the trails by assessing the physical conditions, the patterns of deterioration and the impact rating class of the major trails of Juwangsan National Park. The major trails followed 4 routes including Jubong, Gamaebong, Janggunbong~Geumeungwangi and Woloe. The route length of Jubong was 4.6 km; it was 3.6 km for Gamaebong, 5.6 km for Janggunbong~Geumeungwangi and 5.9 km for Woloe. As for the physical conditions, Jubong was the widest and Janggunbong~Geumeungwangi was the narrowest in trail width. In terms of the bared trail width, Jubong was the widest and Janggunbong~Geumeungwangi was the narrowest. As for the depth of erosion, Gamaebong was the deepest and Woloe was the shallowest. Janggunbong~Geumeungwangi was the steepest and Gamaebong was the gentlest in the slope. Further, Gamaebong showed the highest soil hardness, and Woloe had the lowest hardness. In terms of the times of appearance of deterioration patterns, Jubong recorded 71 times, Gamaebong 62 times, Janggunbong~Geumeungwangi 63 times and Woloe 78 times. In case of the impact rating class, the trail erosion was similar to grades I and II grade; the rest were mostly I grade and hence considered to be in a generally good condition. For the ongoing management of trails, a comprehensive study needs to be conducted in the light of various environmental factors. Also, a restoration plan for damaged trails should be established with consideration for the surrounding environment and ecosystem.

• Journal of Korean Society for Geospatial Information Science
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• v.11 no.1 s.24
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• pp.21-28
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• 2003

This study was aimed at suggest a proper planning method to select a optimal forest road network in mountains forest using GIS(Geographic Information System). To examine the field applicability, the method was applied to the National Forest at Mt. Kumsan in Namhae-gun, Gyungsangnam-do. The main results from altogether six alternative road route plans were derived from these criteria obtained the alternative route plan No.2 has two layout criteria, longitudinal gradient and earth work volume, and it showed similar pattern of existing forest road network which was designed mainly ground slope and longitudinal gradient. The alternative route plan No.6 has four criteria, longitudinal gradient, earth work volume, investment effect and landscape impact. It was different for the lowest forest road density among the alternatives and the pattern of the forest road layout was radial form, which was also quite different to other alternatives. For optimal forest road network planning, GIS provide the efficient and resonable solutions for decision making to provide the support for evaluation about various alternative road networks. If detailed inventory and relevant data are provided and also clear and objective indicators for evaluations are set up, it could be applied to preliminary analysis and detail planning stage to prevent undesirable effect such the land slide and soil erosion due to inadequate planning for forest road network.

• Journal of Korean Society of Forest Science
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• v.85 no.4
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• pp.565-570
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• 1996

The landslide survey in an area of about 10 ha was carried out in Hyuseok-dong. Youngchoon-myeon, Danyang-gun, Choongcheongbuk-do. The results showed that there were many indications on geographical changes, such as scars, depressions, upheavals, cracks and destructions of the construction features. The mean degree of slope of the study area was $28^{\circ}$. The results of surface displacement in this area showed that landslide mass is moving in the direction of SE~SEE, and horizontal and vertical movement rate of the center of moving mass was about 1.2m/year and 0.86m/year, respectively. It was estimated that the amount of the soil erosion in the cliff at the lower edge of this area was 0.823m due to the caving erosion by the Namhangang(River) from June through November, 1995.

• Journal of the Korean GEO-environmental Society
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• v.17 no.6
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• pp.23-31
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• 2016

Nowadays abnormal coldness happens frequently in Korea and frost heaving causes unexpected ground deformation which results in severe problems for structures such as roadway, railroad and cutoff slope. 'Frost heave' as one of the primary phenomenon is considered to be an important factor together with 'adfreeze bond-strength' and 'creep deformation' for structural design process in permafrost area. Therefore, the fundamental study for frost heave has to be preceded for design of geo-structures in cold region. While various experimental apparatuses have been developed, there still exist a certain level of limitation to evaluate the frost-heave characteristics as design parameters. There are no standard testing method and criteria for analyzing frost heaving in Korea because temperature controlled testing apparatuses including a freezing chamber are expensive. In this paper, a new standard freezing and thawing testing apparatus is introduced, which simulates various freezing and thawing conditions in a soil specimen by using a temperature controlled triaxial cell. Frost heaving tests were performed to assess the new testing apparatus and experimental procedure to evaluate frost heaving for soils is proposed.

• Geotechnical Engineering
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• v.8 no.2
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• pp.5-20
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• 1992

The physical-based and lumped-parameter hydrologic groundwater flow model for predicting the rainfall-triggered rise of groundwater levels in hillside slopes is developed in this paper to assess the risk of landslides. The developed model consists of a vertical infiltration model for unsaturated zone linked to a linear storage reservoir model(LSRM) for saturated zone. The groundwater flow model has uncertain constants like soil depttL slope angle, saturated permeability, and potential evapotranspiration and four free model parameters like a, b, c, and K. The free model parameters could be estimated from known input-output records. The BARD algorithm is uses as the parameter estimation technique which is based on a linearization of the proposed model by Gauss -Newton method and Taylor series expansion. The application to examine the capacity of prediction shows that the developed model has a potential of use in forecast systems of predicting landslides and that the optimal estimate of potential 'a' in infiltration model is the most important in the global optimum analysis because small variation of it results in the large change of the objective function, the sum of squares of deviations of the observed and computed groundwater levels. 본 논문에서는 가파른 산사면에서 산사태의 발생을 예측하기 위한 수문학적 인 지하수 흐름 모델을 개발하였다. 이 모델은 물리적인 개념에 기본하였으며, Lumped-parameter를 이용하였다. 개발된 지하수 흐름 모델은 두 모델을 조합하여 구성되어 있으며, 비포화대 흐름을 위해서는 수정된 abcd 모델을, 포화대 흐름에 대해서는 시간 지체 효과를 고려할 수 있는 선형 저수지 모델을 이용하였다. 지하수 흐름 모델은 토층의 두께, 산사면의 경사각, 포화투수계수, 잠재 증발산 량과 같은 불확실한 상수들과 a, b, c, 그리고 K와 같은 자유모델변수들을 가진다. 자유모델변수들은 유입-유출 자료들로부터 평가할 수 있으며, 이를 위해서 본 논문에서는 Gauss-Newton 방법을 이용한 Bard 알고리즘을 사용하였다. 서울 구로구 시흥동 산사태 발생 지역의 산사면에 대하여 개발된 모델을 적용하여 예제 해석을 수행함으로써, 지하수 흐름 모델이 산사태 발생 예측을 위하여 이용할 수 있음을 입증하였다. 또한, 매개변수분석 연구를 통하여, 변수 a값은 작은 변화에 대하여 목적함수값에 큰 변화를 일으키므로 a의 값에 대한 최적값을 구하는 것이 가장 중요한 요소라는 결론을 얻었다.