• Proceedings of the Korean Information Science Society Conference
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• 2000.10b
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• pp.12-14
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• 2000

기존 진화 신경망 연구는 마지막 세대에서 최적의 신경망을 찾는 연구가 대부분이었다. 하지만 이 방법은 마지막 세대의 다른 신경망들이 진화와 학습을 통해 얻은 정보를 모두 무시한다. 최근에는 가능한 많은 정보를 이용해서 보다 뛰어난 성능의 시스템을 구축하기 위해, 마지막 세대의 모든 신경망들의 정보를 결합하는 다중 신경망에 관한 연구가 진행되고 있다. 효과적인 다중 신경망을 구축하기 위해서는 다양한 신경망들이 다중 신경망을 구성해서 서로 보완해 주도록 하여야 하는데, 아직까지 효과적인 다중 신경망 구축 방법은 나오지 않고 있다. 본 연구는 유전자 연산에서 다양한 해를 찾기 위해 사용하는 종분화를 이용해서 다양한 신경망들이 생성되도록 하는 다중 신경망 구축방법을 제안하고 실험을 통해 이 방법의 효용성을 보인다.

• Proceedings of the Korean Information Science Society Conference
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• 2012.06c
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• pp.215-217
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• 2012

인터넷 사용이 보편화 되면서, 이를 악용하는 공격도 지속되고 있다. 이와 같이 네트워크를 통해 전파되는 다양한 공격으로부터 시스템을 보호하기위하여 DDoS 공격 대응 시스템과 스캐닝 공격 탐지 시스템, 스팸형 악성코드 탐지 시스템 등 다양한 보안 시스템들이 사용되고 있다. 본 논문에서는 다양한 인터넷 침해사고에 대응하기 위한 이기종 보안 시스템에서 탐지한 공격 로그를 분석하여 각 시스템별 공격 IP의 공격 지속시간을 확인하고, 서로 다른 침해사고 모니터링 시스템에서 탐지된 공격 IP의 연관 관계를 분석한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2011.04a
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• pp.1485-1488
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• 2011

국방 분야의 시스템 개발은 다양한 데이터표준 및 프로토콜로 인해 체계 간 상호 연동에 어려움이 있다. 특히, 다양한 아키텍처가 적용되는 LVC 연동훈련 체계는 적용 프로토콜 간 데이터 교환을 위해서 공통의 표준기술이 필요하다. 본 논문은 이러한 이기종 체계들 간 상호 연동을 위해서 객체 모델 변환 프레임워크를 제시하였다. 제안 프레임워크는 다양한 이기종 체계가 가지는 객체 모델들과 프로토콜들을 구분하여 독립적으로 연동할 수 있도록 하였다. 또한, 체계 간의 종속성을 줄이고 구성 요소의 유연한 설계를 제공하기 위해서 3-Part 지원 모듈의 플러그인 방식 구조로 설계하였다.

• The Journal of the Korean bone and joint tumor society
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• v.18 no.1
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• pp.37-40
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• 2012

Intraosseous ganglion is a benign cystic lesion. It is composed of fibrous tissue with mucoid changes located in the subchondral bone adjacent to a joint. Intraosseous ganglion has been reported in various skeletal sites and most commonly in the lower end of the tibia and femur. However reports of intraosseous ganglion of the glenoid are rare, with only 14 cases in the literature. We repot 2 cases of intraosseous ganglion of the glenoid with literature reviews.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2022.09a
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• pp.24-24
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• 2022

제주는 면적에 비해 생물종다양성이 높은 지역으로 평가된다. 한반도 자생 관속식물은 4,500여종으로 이 중 50%에 달하는 2,200종이 제주에 분포하고 있으며 최근 30년간 80여종의 미기록 식물이 출현하였다. 이러한 특성은 선태식물과 산림버섯 분야에서도 유사하게 나타나는 것으로 지리적 위치, 기후적 조건, 한라산으로 인한 수직 식생 분포, 특이산림생태계로 인한 입지 환경의 다양성과 관련이 있다. 동시에 제주는 희귀 및 유용 산림생명자원의 보고이다. 제주에서 수집하여 종의 실체를 확인한 2,167종을 대상으로 희귀성과 유용성을 평가한 결과 제주고사리삼, 구상나무, 갯취 등의 희귀·특산 식물이 400종, 흑오미자, 제주백서향, 황칠나무 등의 유용식물이 781종에 달하였다. 또한 제주는 우리나라에서 기후변화에 가장 민감한 지역으로 동북아시아 기후변화의 요충지로 전망되고 있다. 한라산의 구상나무가 쇠퇴하는 등 이상 징후가 지속적으로 증가하고 있으며 동북아시아 아열대 최북한계지로서 한반도 생물지리의 징검다리 역할을 하기 때문이다. 따라서 나고야의정서 발효와 기후위기로 산림생명자원의 보존과 활용의 중요성이 더욱 강조되고 있는 현재의 시점에서 제주는 우선 연구 대상지라 해도 과언이 아니다. 이에 국립산림과학원 난대·아열대산림연구소는 절멸 위기에 처한 종의 보존과 유용 산림생명자원의 활용 기반 마련을 위해 수집 및 탐색-빅데이터 기반 구축-증식기술 개발-현지내·외보존원 조성 및 관리 기술 개발 등의 일련의 연구를 20년 이상 수행해 왔다. 여기에서는 제주지역 산림생명자원의 가치와 함께 보존과 활용 연구 성과를 소개하고 향후 연구 방향을 제안함으로써 산림 바이오 소재 산업화와 관련된 학계와 임업인 및 기업에 도움이 되고자 한다.

• Korean Journal of Heritage: History & Science
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• v.42 no.1
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• pp.72-87
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• 2009

This research is insect diversity analysis on the basis of survey results and bibliographies of Hongdo Island, Mts. Seoraksan, Hallasan, Daeamsan & Daeusan, Hyangnobong peak & Geonbongsan nature reserves and Dokdo Protected Natural Area among 10 designated nature reserves. The Mt. Hallasan nature reserve has 1,867 species in 22 orders and shows the highest species diversity. The species diversities of Mt. Seoraksan, Mt. Hyangnobong peak & Geonbongsan, Hongdo Island, Mt. Daeamsan & Daeusan, and Dokdo Protected Natural Area reveal 1,604 species in 19 orders, 704 species in 18 orders, 474 species in 19 orders, 468 species in 16 orders, and 114 species in 11 orders, respectively, in descending order. The order Lepidoptera shows as dominant taxa in Hongdo, Seoraksan, Hallasan, Hyangnobong peak & Geonbongsan, whereas the order Coleoptera as subdominant taxa in these areas. On the other hand, in Mt. Daeamsan & Daeusan, and Dokdo Protected Natural Area, the order Coleoptera appears as dominant taxa whereas the order Lepidoptera as subdominant taxa. The order Ephemeroptera has been shown the highest species diversity in Seoraksan which is reported to 25 species, Odonata in Hallasan to 28, Dermaptera in Seoraksan to 9, Orthoptera in Hallasan to 51, Hemiptera in Hallasan to 175, Homoptera in Seoraksan to 126, Hymenoptera in Hallasan to 183, and Diptera in Hallasan to 206. The species diversity is generally poor in Daeamsan & Daeusan, Hyangnobong peak & Geonbongsan, and Dokdo Protected Natural Area. Maybe this result is caused by the lack of various academic surveys compared to the other areas. It is needed to study systematic academic investigation on insect in the nature reserve areas in Korea, and to plan appropriate management and conservation on natural environment considering biodiversity of each nature reserve area.

• Journal of Life Science
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• v.16 no.2 s.75
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• pp.213-218
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• 2006

The study of genetic diversity and population structure was carried out in the Codium fragile using allozyme analysis. Although this species has been regarded as a ecologically and economically important source, there is no report on population structure in Korea. Starch gel electrophoresis was used to investigate the allozyme variation and genetic structure of four Korean populations of this species. Of the 15 genetic loci surveyed, nine (60.0%) was polymorphic in at least one population. Genetic diversity was high at the species level ($H_{ES}$=0.144), and, that of the population level was relatively low ($H_{EP}$=0.128). Nearly 87% of the total genetic diversity in C. fragile was apportioned within populations. The predominant asexual reproduction, population fragmentation, low fecundity, geographic isolation and colonization process are proposed as possible factors contributing to low genetic diversity in this species. The indirect estimated of gene flow based on $G_{ST}$ was 1.69. The moderate level of gene flow in C. fragile populations is mainly caused by thallus developed from isolated utricles dispersal via sea current.

• Korean Journal of Environment and Ecology
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• v.30 no.3
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• pp.353-368
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• 2016

This study surveyed the diversity and distributional characteristics of benthic macroinvertebrates and freshwater fish during the period from April to October, 2015 in Seonun Mountain Provincial Park. As a result, a total of 78 species of benthic macroinvertebrates belonging to 50 families, 16 orders, and four phyla were observed in Seonun stream; additionally, 25 species of freshwater fish belonging to six families were identified in all the investigated sites. Among benthic macroinvertebrates, Ephemeroptera(13 spp.: 22.81%) was the largest group in terms of species richness. In the FFGs, gathering-collectors(30 spp.: 36.14%) were relatively larger as represented by Ephemeroptera that usually inhabit fast flowing streams. In the HOGs, clingers(23 spp.: 29.49%) and burrowers(17 spp.: 21.79%) were the dominant groups. For both EPT ratio and ESB index, site 8 appeared to be the highest with 44.44% and 72 marks respectively, while the sites 4 and 9 showed relatively lower rates and indices. According to the results of evaluation, site 8 needs to be designated as the highest protection area while the sites 4 and 9 may be designated as target areas for preferential improvement. According to the analysis of fish community, the dominant species was Zacco teminchkii(333 inds.: 36.80%), and the dominant index was the lowest(0.24) and diversity index was the highest(1.81) at site 8, which therefore represents a stable freshwater fish community. In this survey, six Korean endemic species were identified: Ephemera separigata, Neoperla coreensis, Rhodeus uyekii, Squalidus gracilis majimae, Microphysogobio yaluensis, and Iksookimia koreensis. Also, three species belonging to the management of exportable group(Davidius lunatus, E. separigara, N. coreenis) were observed. Two habitat specific species: Thraulus grandis and Anguilla marmorata, were found for the first time in Gochang area and marked on the Korean distribution map through discussion.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.33 no.4
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• pp.27-34
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• 2005

The paper discussed on the stability of cantilevered pipe conveying fluid subjected to distributed follower force. Governing equations of motion are derived by extended Hamilton's principle, and the numerical scheme using finite element method is applied to obtain the discretized equations. The critical flow velocity as a function of the distributed follower force for the various mass ratio is determined. The flutter configurations of the pipes at the critical flow velocities are drawn graphically at every twelfth period to define the order of quasi-mode of flutter configuration The critical mass ratios, at which the transference of the eigenvalue branches related to flutter take place, are definitely determined. Also, the effect of damping on the stability of the system is considered.

• Korean Journal of Environment and Ecology
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• v.29 no.6
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• pp.907-916
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• 2015

The purpose of this study was to identify characteristics of vegetation structure, vegetation succession, and species diversity of artificially planted Chamaecyparis obtusa (CO) stands. The study was carried out by performing vegetation survey for eight CO stands located in Jeollanam-do Province, Korea. Analysis on vegetation classification and ordinations of the stands was conducted using the data from the vegetation survey, and as a result, the stands were classified into five types of communities. Community I showed a considerably lower index of species diversity when compared to other communities because the canopy of the dominant CO was so highly dense that the low-height vegetation was not able to develop or the low-height vegetation almost disappeared due to elimination of weed trees. Meanwhile, the Community II - IV had relatively higher indices of species diversity because various native tree species mixed with the low-height vegetation and competed with each other in the understory and shrub layers to some degree of stability or in their early stage of vegetation development. Community V, lastly, showed higher use intensity as a recreational forest, thus developing simpler vegetation structure on account of artificial intervention. There was positive correlation between photosynthetically active radiation entering the forest floor, number of observed species and index of species diversity. Such characteristics of vegetation structure in CO stands are closely associated with forest management and prescription for planting reforestation, thinning, and brush cutting in the past. There was a slight difference in vegetation structure and species diversity by communities, based on rotation time of the vegetational succession, process of disturbance frequency and disturbance, development, and maturity by planting CO stands. However, when compared to natural forests, the CO stands showed simpler vegetation structure. Because artificial forests are vulnerable in ecosystem service with lower species diversity, a drive for ecological management is needed for such forests to change into healthy ecosystems that can display functions of public benefit.