• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 봄 학술발표회 논문집
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• pp.549-556
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• 2002

Geotextile tubes hydraulically or mechanically filled with dredged materials have been applied in hydraulic and coastal engineering in recent years(shore protection structure, detached breakwater, groins and jetty). It can also be used to isolate contaminated material from harbor, detention basin dredging, and to use this unit as dikes for reclamation work. Recently, new preliminary design criteria supported by model and prototype tests, and some stability analysis calculations have been studied. The stability analysis of geotextile tube is composed geotechnical and hydrodynamic analysis. The stability check points are sliding failure, overturning, bearing capacity failure against the wave attack. In this paper presented the construction procedure and in-situ measurement(properties of filling material, effective height variation, stress variation at geotextile tube bottom) of geotextile tube at Young-Jin Bay and stability analysis by theoretical method and hydraulic model tests

• 한국농공학회지
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• 제34권E호
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• pp.45-59
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• 1992

At downstream part of the hydraulic structures such as spiliway or drainage gate, jet flow can occur by gate opening. If stream bed is not hard or bed protection is not sufficient, scour hole will be formed due to high shear stress of the jet flow. We call this primary scour. Once the scour hole is formed, a vortex occurs in it and this vortex causes additional scour. We call this secondary scour. The primary scour proceeds to downstream together with flow direction but the secondary one proceeds to upstream direction opposite to it. If the secondary one continues and reaches to the hydraulic structure, it can undermine the bottom of hydraulic structure and this will lead to failure of structure itself. Thus, it is necessary to know the physical features of the vortex structure in a scour hole, which is the main mechanism of the secondary scour. This study deals with the characteristics of the vortex structure and its shear stress which causes the secondary scour.

• 한국조경학회지
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• 제28권1호
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• pp.1-10
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• 2000

The main purpose of this research is to show the consideration of the geographical effects related with its features and configuration on the height of the wall in Hwasong. The method of this research is based on old documentary records and actual measuring. The result of this research is to take advantage of nature geographical features and configuration. First the castle of wall construction is based on outside defensive protection, mainly it was made of stones or bricks. And took advantage of its natural environment. According to circumstance, there were two kinds of general method to build the wall., Second It was considered, They had so many difficulty to move stones to build wall, especially to rugged hilly steep mountain. Third There were three kinds of stones to build wall, Bottom stones were piled with Big stones, because of its stability. Third There were three kinds of stones to build wall, Bottom stones were piled with Big stones, because of its stability. On top of the wall was built with small stones it shows good harmony with small, middle, big size stones. It is considered not only stability but also beauty of appearance. Fourth Placing ChiSung was able to adjust height of wall low at the same time it was also taken advantage of a active defensive power. The suggestion of this research is to take advantage f nature geographical features and at the same time it was a perfect way to save the cost of construction. The further research of this should be continued to deepen because, it is the early stage, so it is maningful of eoffering a guidance for the furder research. in this research has a number of important question remain unsolved.

• 복식
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• 제56권1호
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• pp.44-55
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• 2006

The purpose of this study is to examine the characteristics of man's boots in the Joseon Dynasty and compared them with those of the Ming and Qing Dynasty to find the influential relationships between them. Boots in the Joseon Dynasty are divided into several kinds such as Heukgwejapihwa, Hheuksapihwa(黑斜皮靴), Heukpihwa(黑皮靴), Mokhwa(木靴), Hyeopgeumhwa(挾金靴), Suhwaja (水靴子), Jeonpihwa, Gijahwa(起子靴), and Baekhwa(白靴). In addition, Jeong(精: footwear) was put inside boots. They tend to be named according to their materials or ornaments on them. First, Jeong put inside the boots is regarded as footwear for the comfort of the feet or protection against cold. Mokhwa appears in literature around the 19th century. As shown by remains and paintings of those days, it is considered to have become the common name of boots as it underwent many changes. On the other hand, a book in the era of King Gojong includes pictures of Suhwaja. Compared to Hukpihwa in the same book. The topside seems to have been raised in order to make the wearer who put on a military uniform feel comfortable when walking, since the bottom piece is hard. Baekhwa is worn not only with funeral garments but also with Sibok(時服), one of official uniforms. Boots in the Joseon Dynasty had been made following the design of the Ming Dynasty since official uniforms were conferred upon King Gongmin in the late Koryo Dynasty. But turning the late Joseon Dynasty its detailed design changed little by little. The topside of the boots became more round, the entrance part became wider, height of the shoes became taller, and the bottom piece became parallel to the ground.

• 한국항해항만학회지
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• 제28권7호
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• pp.619-627
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• 2004

Introduction of wave model, considered the effect of shoaling, refraction, diffraction, partial reflection, bottom friction, breaking at the coastal waters of complex bathymetry, is a very important factor for most coastal engineering design and disaster prevention problems. As waves move from deeper waters to shallow coastal waters, the fundamental wave parameters will change and the wave energy is redistributed along wave crests due to the depth variation, the presence of islands, coastal protection structures, irregularities of the enclosing shore boundaries, and other geological features. Moreover, waves undergo severe change inside the surf zone where wave breaking occurs and in the regions where reflected waves from coastline and structural boundaries interact with the incident waves. Therefore, the application of mild-slope equation model in this field would help for understanding of wave transformation mechanism where many other models could not deal with up to now. The purpose of this study is to form a extended mild-slope equation wave model and make comparison and analysis on variation of harbor responses in the vicinities of Ulsan Harbor and Ulsan New Port, etc. due to construction of New Port in Ulsan Bay. We also considered the increase of water depth at the entrance channel by dredging work up to 15 meters depth in order to see the dredging effect. Among several model analyses, the nonlinear and breaking wave conditions are showed the most applicable results. This type of trial might be a milestone for port development in macro scale, where the induced impact analysis in the existing port due to the development could be easily neglected.

• 한국전산유체공학회지
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• 제21권4호
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• pp.33-39
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• 2016

Generally, thermal analysis of spent fuel storage cask has been conducted using the porous media and effective thermal conductivity model to simplify the structural complexity of spent fuel assemblies. As the fuel assembly is composed of two regions; active fuel region corresponding to UO2 pellets and unactive fuel region corresponding to the top and bottom nozzle, the heat transfer performance can be influenced depending on porous media application at these regions. In this study, numerical analysis on concrete storage cask of spent fuel was performed to investigate heat transfer effects for two cases; one was porous media application only to active fuel region(case 1) and the other one was porous media to whole length of fuel assembly(case 2). Using computational fluid dynamics code, the three dimensional, 1/4 symmetry model was constructed. For two cases, maximum temperatures for each component were evaluated below the allowable limits. For the case 1, maximum temperatures for fuel cladding, neutron absorber and baskets inside the canister were slightly higher than those for the case 2. In particular, even though the helium flows with low velocity due to buoyant forces occurred at the top and bottom of unactive fuel region, treating only active fuel region as the porous media was ineffective in respect of the heat removal performance of concrete storage cask, implying a conservative result.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2004년도 Asia Navigation Conference
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• pp.217-225
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• 2004

Introduction of wave model, considered the effect of shoaling, refraction, diffraction, partial reflection, bottom friction, breaking at the coastal waters of complex bathymetry, is a very important factor for most coastal engineering design and disaster prevention problems. As waves move from deeper waters to shallow coastal waters, the fundamental wave parameters will change and the wave energy is redistributed along wave crests due to the depth variation, the presence of islands, coastal protection structures, irregularities of the enclosing shore boundaries, and other geological features. Moreover, waves undergo severe change inside the surf zone where wave breaking occurs and in the regions where reflected waves from coastline and structural boundaries interact with the incident waves. Therefore, the application of mild-slope equation model in this field would help for understanding of wave transformation mechanism where many other models could not deal with up to now. The purpose of this study is to form a extended mild-slope equation wave model and make comparison and analysis on variation of harbor responses in the vicinities of Ulsan Harbor and Ulsan New Port, etc. due to construction of New Port in Ulsan Bay. This type of trial might be a milestone for port development in macro scale, where the induced impact analysis in the existing port due to the development could be easily neglected.

• 디지털융복합연구
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• 제13권9호
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• pp.129-136
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• 2015

본 논문은 학제간 연구의 대표적인 사례인 빅데이터 연구가 어떤 주제로 구성되어 있는지를 상향식 접근법을 이용하여 분석한다. 분석을 위해서 연구재단에서 제공하는 학술지 인용색인시스템을 이용하였다. 영문 키워드 "big data"로 모든 등재지와 등재후보지를 대상으로 검색을 하여 이것을 원천 데이터로 하였다. 논문 저자가 직접 제공하는 키워드를 본 연구에서 사용하기 위해서 정제작업을 거친 후, 주요 키워드 분포, 참여 저널의 성격 분포, 참여저자 수의 분포, 연도별 키워드 분포 등을 이용하여 빅데이터 연구주제의 구조를 설명하였다. 식별된 주요 키워드들은 사회네트워크 분석, 하둡, 맵리듀스, 개인정보/보호, 클라우드 컴퓨팅, 시각화, 데이터마이닝 등이다. 또한 빅데이터가 지속가능하고 융복합적인 경영혁신 도구로 사용되기 위해 향후 추가적으로 보완되어야 할 연구 키워드들을 제안한다.

• 한국해양학회지:바다
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• 제19권1호
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• pp.66-75
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• 2014

본 연구는 동해 남부 이산화탄소 해저지중저장 후보지 주변 수심 100-500 m 해역에서 저서생태계의 공간분포와 이를 결정하는 환경요인을 이해하기 위해 수행되었다. 2012년 8월-9월 총 16개 정점에서 대형저서동물군집과 환경요인을 조사하였다. 총 158종의 저서동물이 채집되었으며, 평균 서식밀도는 $843indiv/m^2$, 평균 생물량(습중량)은 $26.2g\;WW/m^2$로 나타났으며, 생물다양성이 높은 지역에서 주로 서식밀도가 높았다. 측정된 33개 환경변수를 대상으로 주성분분석을 실시한 결과 조사해역의 저서환경은 크게 퇴적물환경, 저층해수환경, 수심에 의해 지배된다. 저서동물의 분포는 세 가지 주성분과 밀접한 관련을 보였는데, 특히 사질함량이 많은 정점일수록 출현종수가 많아지고 생물량은 적어지는 경향이 관찰되었다. 조개 2종을 포함한 우점종 6종은 ${\Omega}$ aragonite, ${\Omega}$ calcite 농도가 높은 곳을 선호하였는데, 이 종들은 이산화탄소 유입으로 인해 해양산성화가 진행되면 가장 먼저 피해를 입을 수 있는 생물로 판단된다. 저서동물 상위 1% 우점종의 종조성을 바탕으로 집괴분석한 결과 지리적으로 뚜렷하게 구분되는 4개의 정점군이 분류되었다. 각 정점군은 고유의 저층해수 및 퇴적물 환경을 보이고 있으며, 대표적인 특성종으로는 A) Ampelisca miharaensis, (B) Edwardsioides japonica, (C) Maldane cristata, (D) Spiophanes kroeyeri을 들 수 있다. 측정이 용이한 5개의 환경요인(수심, 사질함량, 수온, 염분, pH)을 이용하여 4개의 정점군을 정확도 100%로 예측할 수 있는 판별함수모델을 제시하였다. 조사지역의 저서동물군집은 환경요인과 밀접한 관계를 보이고 있으며, 이는 환경변수에 기반하여 저서동물 분포를 예측할 수 있는 통계적모델 개발 가능성을 시사한다.

• 헤리티지:역사와 과학
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• 제48권3호
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• pp.80-95
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• 2015

본 연구의 목적은 서남해안 갯벌의 보호 및 관리 체계 모델을 제시함으로써 세계유산 신청을 위한 효율적인 보호 및 관리 체계를 구축하는데 있다. 서남해안 갯벌은 유네스코 세계유산에서 강조하고 있는 탁월한 보편적 가치에 대한 잠재적 가능성을 가지고 있다고 판단된다. 서남해안의 갯벌이 세계유산으로 등재되어 체계적으로 관리된다면 자연자원의 현명한 사용(wise use)을 통한 인간과 자연의 조화에 의해 전 세계 모든 인류가 지향해야할 지속가능한 발전을 이룩하는 대표적인 모범 사례가 될 수 있을 것이다. 이러한 관점에서 현재 서남해안 갯벌 대상지역의 보호 및 관리체계를 조사하고, 해외 유사 유산의 관리 사례 조사를 통해 서남해안 갯벌의 관리방향과 체계를 위한 현재의 관리정책을 수정하고 보완사항을 도출하여 우리의 실정에 맞는 모델을 제시하는 것은 세계유산 등재 추진을 위해 반드시 필요한 일이다. 서남해안 갯벌에 해당되는 전체 잠정목록 대상지에 대한 조사 결과, 세계유산의 보호를 위한 합리적인 관리체계를 개발하기 위해서는 보호지역의 추가 지정 및 확대가 필요한 상태이다. 또한 현재의 관리체계는 등재 추진부서(예 : 문화관광과)와 실제 갯벌 관리부서(예 : 해양수산과)로 이원화되어 있다는 문제점이 있다. 이러한 관리부서의 이원화는 세계유산을 합리적으로 추진하기 위한 중장기적인 관리계획을 수립하고 단위사업을 수행하고, 또한 향후 세계유산을 효율적으로 관리하기에 상당한 문제를 야기할 수 있다. 따라서 서남해안 갯벌의 세계유산 등재를 위해서는 보호지역의 확대와 지자체별 이원화된 관리체계의 통합, 그리고 중장기적 통합관리 계획을 수립하는 것이 필요하다. 이를 위해서는 서남해안 갯벌의 효율적이고 지속가능한 보호 및 관리를 위한 관 학 민 NGOs 등 다양한 이해 당사자들의 통합을 위한 협업체계를 구축하는 것이 필수적이다. 즉, 와덴해의 사례와 같이 민관산학의 협의체를 구성하여 유산의 보호 및 관리의 핵심주체인 지역주민의 토착지식과 의견을 기반으로 다양한 이해 당사자들의 의견을 모아, 이를 지역 또는 국가의 정책으로 입안하여 채택하는 상향식 구조를 갖는 것이 필요하다. 중장기적 관점의 통합계획에 있어서는 서남해안 갯벌의 자연 문화유산 보전 및 관리 통합계획 '서남해안 갯벌의 자연과 문화유산 보전 및 관리 통합계획(Integrated Plan for Conservation and Management on Natural and Cultural Heritages in Southwestern Coast Tidal Flat)'의 수립을 제안한다.