• Journal of Korea Water Resources Association
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• 제51권4호
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• pp.347-354
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• 2018

In urban areas, runoff flow is drained through sewer networks as well as surface areas. Therefore, it is very important to consider sewer networks as a component of hydrological drainage processes when conducting urban inundation modelling. However, most researchers who have implemented urban inundation/flood modelling, instinctively simplified the sewer networks without the appropriate criteria. In this research, a 1D-2D fully coupled urban inundation model is applied to estimate the influence of sewer network simplification on urban inundation modelling based on the dendritic network classification. The one-dimensional (1D) sewerage system analysis model, which was introduced by Lee et al. (2017), is used to simulate inlet and overflow phenomena by interacting with surface flow. Two-dimensional (2D) unstructured meshes are also applied to simulate surface flow and are combined with the 1D sewerage analysis model. Sewer network pipes are simplified based on the dendritic network classification method, namely the second and third order, and all cases of pipes are conducted as a control group. Each classified network case, including a control group, is evaluated through their application to the 27 July 2011 extreme rainfall event, which caused severe inundation damages in the Sadang area in Seoul, South Korea. All cases are compared together regarding inundation area, inflow discharge and overflow discharge. Finally, relevant criterion for the simplification method is recommended.

• Journal of Soil and Groundwater Environment
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• 제7권3호
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• pp.45-59
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• 2002

This study is objected to demonstrate the spatial variability of the ground-water recharge by classifying the types of ground-water hydrographs and assessing the recharge ratio(the ratio of the rise of ground-water level to cumulative precipitation) of each type using the National Ground-water Monitoring network data. A total of 5 types were identified by factor analysis on the ground-water hydrographs nationwide. The recharge ratio of each type were estimated to be 6.5% (TYPE I), 4.1 % (TYPE II), 9.2%(TYPE III), 5.8 %(TYPE IV), 15.3 %(TYPE V) in the confidence level of 95.44% and 6% variation was estimated site by site even in the same type. The recharges of Han, Nakdong, Keum, Youngsan·Seomjin river basins were estimated as 10.0 %, 6.1 %, 8.3 %. and 6.6 % respectively. These results were consistent with the results of the existing baseflow method.

• Proceedings of the Korea Water Resources Association Conference
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• 한국수자원학회 2020년도 학술발표회
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• pp.293-293
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• 2020

기후변화로 인해 다양한 재난이 복합적으로 발생하고 있으며, 특히 해안과 인접해 있는 지역은 풍랑, 지진해일 등으로 인해 다양한 위험에 노출되어 있는 실정이다. 이에 따라 각 지자체는 자연재해대책법에 의거하여 자연재해저감종합계획을 수립하고 저감대책을 마련하고 있으나, 수립 절차에 따른 비용과 시간이 많이 소요되고 있다. 따라서 위험지역의 지리적·사회적 조건을 고려한 맞춤형 재해예방기법 도출방안이 필요하다. 이에 본 연구에서는 과거 피해이력과 침수예상도 정보가 반영된 위험성평가 지도를 활용하여 위험지역 유형을 4단계(관심, 주의, 경계, 위험)로 구분하고, 단계별 구조물적 대책과 비구조물 대책의 적용방안을 제시하였으며, 구조물적 대책과 비구조물적 대책의 도출에는 지역맞춤형 요소와 특성요소를 활용하였다. 지역맞춤형 요소는 자연인자, 재해영향인자, 재해원인인자, 지형인자, 사회인자로 구분하였으며, 각 인자별로 세부인자를 선택하여 논리연산에 따라 재해예방기법을 도출하였다. 특성요소는 효율성, 시공성, 공공성으로 구분하였고, 각 구분별 세부요소를 평가하여 재해예방기법의 우선순위를 도출하였다. 본 연구를 통해 향후 해안가 복합재난이 예상되는 지역을 대상으로 지역맞춤형 재해예방기법을 도출할 수 있을 것이며, 자연재해저감종합계획 수립 시에도 활용할 수 있을 것으로 기대된다.

• Proceedings of the Korea Water Resources Association Conference
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• 한국수자원학회 2009년도 학술발표회 초록집
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• pp.442-446
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• 2009

최근의 극심한 가뭄현상과 4대강살리기 사업 등 하천과 관련된 국가적인 일들이 진행되고 있어 하천관리에 대한 국민적 관심이 증가하고 있다. 그 동안 하천의 관리는 국가와 지방이 각기 따로 따로 해왔고, 하천 역시 국가하천과 지방하천으로 구분되어 있다. 국가하천 구간은 전체 하천 연장의 10% 이내이기 때문에 대부분의 하천관리는 지방이 담당하고 있다고 해도 과언이 아니다. 그러나 현실적으로 지방행정기관의 하천관리 인력은 턱없이 부족한 실정이다. 기후변화와 물수요 증가 등 하천관리에 대한 중요성과 하천을 행정구역이 아닌 유역 중심으로 관리해야하는 필요성이 증대됨에 따라 최근 국토해양부는 하천법 개정(2008.4)을 통해 국토보전상 또는 국민경제상 중요한 하천을 추가로 국가하천으로 지정할 수 있는 법적 기반을 만들었다. 하천에 대한 등급의 조정은 이해당사자들의 관계 및 지자체간의 문제 등 다양한 변수들이 존재하기 때문에 쉬운 작업은 아니다. 추가로 지정하기 전에 좀 더 세부적인 고민이 요구된다는 것이다. 그렇다면 어떤 하천이 국토의 보전과 국민경제적으로 중요한 하천인지, 어느 정도나 국가하천으로 지정되어야 하는지, 국가하천과 지방하천으로 구분하는 이유는 무엇이고 꼭 그렇게 구분해야 하는지, 국가하천과 지방하천의 관리를 위해 중앙정부와 지자체의 역할과 기능은 무엇이어야 하는지 등이 검토되어야 한다. 하천관리에 요구되는 기능과 역할을 누가 어떻게 책임지고 하는지에 따라 향후 하천관리에 큰 영향을 줄 것이다. 본 연구에서는 하천관리의 효율성 측면에서 이 같은 점들에 대한 답을 하고자 하였다. 특히 국가하천의 추가 지정과 관련된 문제점과 향후의 정책방향을 제시하였다.

• Proceedings of the Korea Information Processing Society Conference
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• 한국정보처리학회 2004년도 춘계학술발표대회
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• pp.1007-1010
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• 2004

본 논문에서는 분산 서비스거부 공격(DDoS)이 발생할 때 네트워크 트래픽의 특성을 분석하기 위해서 트래픽 비율분석법(TRA: Traffic Rate Analysis)을 제안하고 트래픽 비율분석법을 통해서 분석된 다양한 유형의 DDoS 공격의 특성을 기계학습(Machine Learning)을 이용해서 DDoS 공격의 탐지규칙을 생성하고 그 성능을 측정하였다. 트래픽 비율분석법은 감시대상 네트워크 트래픽에서 특정한 유형의 트래픽의 발생비율을 나타내며 TCP flag rate 와 Protocol rate 로 구분된다. 트래픽 비율분석법을 적용한 결과 각각의 DDoS 공격 유형에 따라서 매우 독특한 특성을 가짐을 발견하였다. 그리고, 분석된 데이터를 대상으로 세 개의 기계학습 방법(C4.5, CN2, Na?ve Bayesian Classifier)을 이용해서 DDoS 공격의 탐지규칙을 생성하여 DDoS 공격의 탐지에 적용했다. 실험결과, 본 논문에서 제안된 트래픽 비율분석법과 기계학습을 통한 DDoS 공격의 탐지방법은 매우 높은 수준의 성능을 나타냈다.

• Journal of Plant Biotechnology
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• 제33권4호
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• pp.283-288
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• 2006

Discrimination of 5 rice cultivars (Sangjubyeo , Dongjinbyeo Simbaekbyeo , Hwamanbyeo , and Simbaek-hetero ) using metabolic profiling was carried out. Whole cell extracts from each cultivar were subjected to $^1H$ NMR spectroscopy. When spectral data were analyzed by principal component analysis, 5 cultivars were clustered into 3 groups: SJ, DJ + SB, and HM + SH. Thecultivars showed great difference in carbohydrate region of $^1H$ NMR spectra, suggesting that qualitative and quantitative differences in carbohydrate compounds play a major role in discrimination of the cultivars. In addition, it was readily possible to determine relative quantification of major carbohydrates including sucrose, glucose, maltose from spectral data of the cultivars. SJ showed 2 to 4 times higher content of maltose than the other rice cultivars. Overall results indicate that metabolic discrimination of rice cultivars using $^1H$ NMR spectroscopy combined by multivariate statistical analysis can be used for rapid discrimination of numerous rice cultivars and simple quantitative analysis system of major carbohydrate compounds in rice grains.

• Journal of Korean Society of Forest Science
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• 제79권2호
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• pp.144-161
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• 1990

Pine forest communities developed in Mt. Palgong, southeastern Korea, were studied phytosociologically, with special reference to multiple management of local forests, and were classified into two communities, Pinus densiflora - Quercus mongolica community(I : mountain forest) and P. densiflora-Climbing plants community (II : valley forest) and six subgroups accompanied by several subgroups. Judging from the coincidence method, the division of communities (vegetation units) was closely related to altitude and topography. Based on vegetation units, a vertical distribution map of pine forest communities was prepared. The species composition(%) of pine forest communities under stratification, in upper and lower tree layer, teas I higher than II, in middle and shrubs lacer II higher than I (Total : Upper 15.5%, Middle 28.4%, Lower 34.6%. Shrubs 21.5%. Sum of mean coverage%i of understory vegetation was II twice as high as I (Total. shrubs 28.4%. forbs 11.4%, Graminoids 11.8%, ferns 1.0%). Based on constance, coverage and d.b.h. class etc., an actual growth and occurrence table of tree species and understory vegetation by vegetation unity were prepared, and could assume a criterion for judging potential dominance-growth conditions.

• Journal of the Korean Society for information Management
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• 제35권4호
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• pp.37-50
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• 2018

The purpose of this study is to analyze the first edition of Brown's Subject Classification and to understand the implications of today's library classification. For this purpose, the first edition of the Subject Classification published in 1906 was analyzed. The analysis results are divided into three main areas. First, SC is divided into eleven main classes and each class is subdivided into enumerated subdivisions from 000 to 999. Second, As a method of synthesizing the classification numbers, there were three methods of synthesis. There was a flexibility to insert a new classification number at the appropriate location when a new topic that does not appear in the main table appeared. Implications for classification studies can be divided into four main categories. First, SC proposed a method of classification number synthesis for composite topics, which is an innovative method that was not available in previous library classification. Second, the subject matter was explained in various aspects through the operation of auxiliary tables supporting the facets. Third, it is possible to easily insert a new topic into the classification system by using the SC that can have a flexible classification system for each library, or to use a short classification number according to the size of the library collection. Fourth, it provided a directory that can be considered as access points for digital materials.

• Journal of Legislation Research
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• 제41호
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• pp.43-85
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• 2011

Child and youth welfare law in Korea is vague and complex. In a narrow sense it means the research on the provisions of the Child Welfare Act. In a broad sense it embraces all of the social welfare system regarding to the protection for children and youth. Regardless of the scope of child and youth welfare law it should be cleared what the term of child and youth means in Korean legal regulation. Historically, child protection in Korea was based on the good intentions of individuals to protect war orphan children from poverty or danger after the end of the Korean War. It is the story of the evolving status of children from being viewed as dependant of the parents to becoming rights-based citizens, even not in Constitution. In Korea neither parents nor children have constitutionally recognized right. According to Korean Constitution the parents have only the obligation to educate their children. And the state ist obliged to improve the welfare of the youth(section 34). In compliance with this article there are lots of statutes regulating youth welfare. This article reviews the legal definition of child and youth to test the uncertain definition of child and youth welfare in relation to the treatment of children's and youth's legal status in Korea. According to the Child Welfare Act child is the person under age of 18, while the legal definition of youth oscillates between the person under the age of 19 and the person over the age 9 to the age of 23. As a result child welfare is often used as the synonym of youth welfare, and vice versa. The lack of the arrangement of the legal definition of child and youth is based on the historical reasons that the legal definitions of youth (under the age of 19 or over the age 9 to the age of 23) newly appeared in the statutes regulating youth welfare, whereas the Child Welfare Act still maintained the definition of child under the age of 18. In order to get rid of the confusion of the definition of the child and youth, a part of certain statues should combine with another Act according to the purpose of the individual amended statutes. And the definition of child and youth should be subdivided into 3 or 4 classes, namely infant(0-6), child(7-13), youth(14-18) and young adult(19-26). Furthermore this article proposes a reform of the existing legal system pursuant to the nature of the law, i.g. whether the issued or amended Act takes on a selective(residual) or universal character.

• Journal of Korean Society of Forest Science
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• 제84권2호
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• pp.247-257
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• 1995

This research carried out forest community classification on the basis of the methods of ZM school, in order to furnish useful information needed for forest management, and for afforestation and preservations of Abies koreana forest which was Korean native species, and the research results could be summarized as follows. Abies koreana forest was divided into 10 vegetation units ; This forest was divided into Abies koreana-Quercus mongolica community and Abies koreana-Sasa quelpartensis community. Abies koreana-Quercus mongolica community was divided into Tripterygium regelii group, Patrinia saniculaefolia group, and Typical group, and Tripterygium regelii group seas divided into Typical subgroup. Pimpinella brachycarpa subgroup, and Hemirocallis fulva subgroup. Abies koreana-Sasa quelpartensis community was divided into Berberis koreana group, Trachelospermum asiaticum var. intermedium group, and Typical group. Berberis koreana group was divided into Typical subgroup and Hepatica asiatica subgroup, and Tranchelospermum asiaticum var. intermedium group was divided into Hepatica asiatica subgroup and Typical subgroup. According to the results of the analysis by coincidence method, Abies koreana-Quercus mongolica community represented in Mt. Chiri, Mt. Deokyu and Mt. Kaya which were located in the Sobaek mountains, Abies koreana-Sasa quelpartensis community represented in Mt. Hanla. Therefore it was thought that Abies koreana forest was classified by geographical position, and vegetation units of Abies koreana forest tended to be classified by the altitude and topography. As for DBH and height of Abies koreana, mean DBH and height of Abies koreana-Quercus mongolica community were each 28.4cm, 10.6m that were larger than mean DBH and mean height(each 23.6cm, 6.3m) of Sasa quelpartensis community. Among Abies koreana-Quercus mongolica community, Patrinia saniculae-folia group had the smallest mean DBH and mean height(20cm, 5m), and among Abies koreana-Sasa quelpartensis community, Typical group had the smallest mean DBH and mean height(4cm, 3m).