• Journal of Navigation and Port Research
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• v.46 no.6
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• pp.483-490
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• 2022

Floating LiDAR is a system that provides a new paradigm for wind condition observation, which is essential when creating an offshore wind farm. As it can save time and money, minimize environmental impact, and even reduce backlash from local communities, it is emerging as the industry standard. However, the design and verification of a stable platform is very important, as disturbance factors caused by fluctuations of the buoy affect the reliability of observation data. In Korea, due to the nation's late entry into the technology, a number of foreign equipment manufacturers are dominating the domestic market. The west coast of Korea is a shallow sea environment with a very large tidal difference, so strong currents repeatedly appear depending on the region, and waves of strong energy that differ by season are formed. This paper conducted a study examining buoys suitable for LiDAR operation in the waters of Korea, which have such complex environmental characteristics. In this paper, we will introduce examples of optimized design and verification of ship-type buoys, which were applied first, and derive important concepts that will serve as the basis for the development of various platforms in the future.

• Journal of the Korean Institute of Landscape Architecture
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• v.39 no.6
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• pp.36-45
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• 2011

Public open space(Gong-Gae-Gong-Ji) is an important part of the open-space system in an urban environment. Though part of the private sector, it has a significant public function as there are as always open to the free use of every citizen for rest and amenities. A field survey of the public open space of 71 major buildings was carried out to investigate the actual state of public open spaces in the city of Daegu. As a result of this investigation, several point of issues were discussed. In distribution by 'Gu', newly-emerging sub-centers of Daegu-City, such as Bug-Gu and Dalseo-Gu as well as downtown area have many public open spaces. By the use type of buildings, retail buildings such as shopping centers and SSM account for36.6%, business buildings21.1%, and residential and commercial complexes 15.5%, respectively. Location wise, the front areas accounted for the greatest amount(42.9%) with 1 in side area(20%), and 2 in the front/side area(20%), respectively. Degree of division was 1 spot type(45.7%), 2 division type(35.7%). The misuse of public open space for private use, such as shopping and parking lots, was26.6%. On the basis and analysis of the actual status, 6 improvement devices for public open spaces were suggested: 1) The improvement of the legal regulative system, 2) the establishment of design guidelines and strengthening of deliberation, 3) administrative and financial support, 4) periodic supervision and guidance, 5) installment of signs that shows the space is open for use to every citizen, and 6) the participation of citizens in management of public open space.

• Korean Journal of Environment and Ecology
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• v.17 no.2
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• pp.105-111
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• 2003

To develope reforestation methods for enviromentally sound and ecological forest management, Fraxinus rhynchophylla stand structure and radial growth of the trees were invstigated and compared by study sites. Plantation forest studied on Fraxinus rhynchophylla, was located at Jawoon-ni Nae-myeun, Hongcheon-gun and natural forest studied on Fraxinus rhynchophylla, was located at Jangjeon-ni Jinbu-myeun, Pyeungchang-gun. In 7,8 years after planting, differences of annual diameter increment among three stand origins were significant. The highest mean annual diameter increments of F. rhynchophylla, 4.60 mm/year was measured in sprouting trees, and followed by natural seedlings 4.59 mm/year. The lowest values, 4.18mm/year did in planting trees. Early radial growth of planting F. rhynchophylla was measured lower than that of sprouting or natural seedlings. These facts mean that planting F. rhynchophylla is not proper regeneration methods. Other regeneration methods of F. rhynchophylla forest, by sproutings, direct seeding and natural seeding, might be researched and recommended.

• Proceedings of the Materials Research Society of Korea Conference
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• 1994.11a
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• pp.98-98
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• 1994

최근 청색반도체레이저의 실현을 위하여 ZnSe가 대표하는 II-Ⅵ족 화합물반도체와 Gan가 대표하는 III족 질화물반도체분야에서 집중적인 연구가 이루어지고 있으며, 아직까지 실용화 되지 않고 있는 청색반도체레이저의 출현에 대하여 많은관심이 모아지고 있다. III족 질화물반도체는 InM(Eg:1.9eV)부터 AIN(Eg: 6.2eV)에 이르기까지 전 조성영역에서 완전한 고용체를 이루며, 실온에서 직접천이형 에너지 대구조를 가지므로 청색 혹은 자외영역에서 동작하는 발광소자를 제작하는데 있어 유망시 되고 있는 소재이다. 특히 GaN와 InN의 3원흔정인 GaInN를 활성층으로 이용하면 그 발전파장을 370nm부터 650nm까지 즉 가시 전 영역으로부터 근 자외영역을 포함할 수 있게 된다. 이 연구에서는 AIGaN/GaInN 이중이종접합(DH) 구조의 고아여기에 의한 유도방출고아의 편광 특성을 조사하였다. 유기금속기상에피텍셜(MOVPE)법으로 성장한 AIGaN/GaInN DH 구조의 표면에 수직으로 펄스 발진 질소레이저(파장: 337.1cm, 주기 10Hz, 폭: 8nsec) 빔을 조사하고 DH구조의 단면으로부터의 유도방출광을 편광기를 통과 시킨 후 스펙트럼을 측정하였다. 입사고아 밀도가 증가함에 따라 약 402nm의 파장에서 유도발출에 의한 가도가 큰 피크가 나타났고, 그 반치폭은 약 18meV이었다. 실온에서 AIGaN/GaInN DH 구조로 부터의 유도방출에 필요한 입사광밀도의 임계치는 약 130㎾/$\textrm{cm}^2$이었다. 한편 편광각이 90$^{\circ}$일때는 발광스펙트럼의 강도가 매우 낮고 단지 자연방출에 의한 스펙트럼만이 나타났다. 편광각이 0$^{\circ}$일 때 최대의 방출광 강도를 나타내었으며, 편광각이 -90$^{\circ}$로 회전함에 따라 발고아강도의 강도가 감소하였다. 이와 같은 결과는 광여기에 의하여 AIGaN/GaInN DH 로 부터의 유도방출광이 GaInN활성층의 단면에 평행한 전기장의방향으로, 즉 TE모드로 선형적으로 편광됨을 의미한다. AIGaN/GanN DH 로 부터의 유도방출이 선형적으로 TE모드로 편광되는 것은 이 구조를 이용한 청색 및 자외선 반도체 레이저다이오드의 실현에 매우 유익한 것이다.

• Journal of Digital Convergence
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• v.14 no.5
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• pp.411-420
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• 2016

Movement of Province Government Office of Chungcheongnam-do is pursued to balance regional development of South Chungcheong Province. The Head Office was built in Naepo area(Hongsung & Yeasan) which is located in the center of Chungnam geographically to promote balanced regional development. Stage two goals for 2015 of city construction is staying at the level of 20 %. The cause is very complicated, but it can be explained by central government agencies in the establishment of the Sejong City and relocation of the central government policy support. This study is looking for new strategies to get competitive power and Regional Festival which leads the mood and industry in the new city, Naepo.

• Journal of the Korean GEO-environmental Society
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• v.13 no.12
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• pp.35-42
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• 2012

There are many large-scale coastal region landfill and land development by loading to use territory efficiently, this regions are mostly soft clay ground. Constructing structures and road on the soft ground bring about engineering problems like ground shear fracture and a big amount of consolidation by bearing capacity. Improvement of soft soil is required to secure soil strength and settlement control. In improvement of soft soil, predict for the amount of settlement based on field surveyed reports are important element for estimating pre-loading banking height and the final point of consolidation. In this study, there is calculating theoretical settlement by analyzing field surveyed report and ground investigation to improvement of soft soil with pre-loading and vertical drain method. And present settlement prediction method reflect soil characteristics in Gimpo Hangang site by analysing prediction settlement and observational settlement during compaction using hyperbolic, ${\sqrt{s}}$, Asaoka method.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.10 no.1
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• pp.72-81
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• 2007

This study mainly aims at suggesting plans applicable to the outdoor of environment-friendly communities in Korea by leveraging more natural conditions and materials when creating an outdoor biotop for an environment-friendly community and generating material types and development techniques enabling a natural circulation system. To this end, materials used in the outdoor of environment-friendly communities and traditional residential areas in Korea and biotop materials found in natural areas were examined. First, when the case examples of environment-friendly communities were reviewed, biotop spaces and materials that may function as habitats were hardly found. Materials used in biotop were mainly man-made structures made of artificial or processed materials, such as concrete, stones, bricks, woods and steels. Meanwhile, the outdoor space of traditional Korean villages had stone walls, soil walls, rock piles and composite piles, which composed of natural materials such as rocks, soil and plants, that naturally formed porous spaces along with the introduction of plants and provided habitats for a variety of insects. In natural areas, naturally created biotop spaces, such as rock piles, log piles, old tree deployment, branch piles, hay stacks and defoliated leaves, were found. Meanwhile, when spaces and materials available for biotop creation were reviewed to create an environment-friendly residential complex, they were divided into fences and hedges, green spaces between parks and residential buildings, ponds and waterscape spaces, zones separating pedestrian walks and roadways, breast walls and slope boundary, plant box and pergola. For each space, materials used for creating biotops and that were found in traditional Korean residential areas and natural areas were applied and suggested.

• Journal of the Korean Geosynthetics Society
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• v.12 no.4
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• pp.45-56
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• 2013

Recently, offshore wind farms are increasingly expected, because there are huge resource and large site in offshore. Jeju island has optimum condition for constructing a wind energy farm. Unlike the mainland, Jeju island has stratified structure distribution between rock layers sediments due to volcanic activation. In these case, it can be occur engineering problems in whole structures as well as the safety of foundation as the thickness and distribution of sediment under top rock layer can not support sufficiently the structure. In this paper, the settlement and stress distribution is predicted by numerical analysis when the mono-pile base are constructed on various soft layer between stratified structure. To determine the settlement of the pile foundation supported on stratified rock layer, the geological investigation at the 3 regiions and the results of laboratory experiments of the stratified rock layer is required.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.10
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• pp.4869-4876
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• 2012

This study was performed to propose a improvement guide for the region of Seosan located at the north-west part of Chungnam province. Thus, this study recognizing that urban revitalization design of Seosan should be established based on inheritance of regional history and traditional culture. This study was processed with following procedures and methods. First, this study drew the recent trends and effective ways as proportion system of urban revitalization design through collecting and analyzing literatures. Second, performed to the survey of the consciousness consider urban environmental settlement of residents in Seosan using a statistical method. Third, carried out case studies as urban revitalization design of central area in Seosan.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.219.1-219.1
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• 2010

매립지에서 유기물의 분해로 발생되는 매립가스는 악취 등으로 인한 대기오염뿐만 아니라 온난화지수가 21인 메탄이 약 50vol% 포함되어 있어 지구온난화에 큰 영향을 미친다. 하지만 매립가스를 에너지원으로 활용하면 대기오염저감, 지구온난화 감소, 대체에너지원 확보뿐만 아니라 CDM사업 등과 연계하여 부가수익창출이 가능하다. 현재 국내에는 약 242개의 폐기물매립지가 있는데, 이중 매립가스를 활용하는 곳은 단지 14개소로 개별 경제성이 있는 대형매립지에서만 자원화시설을 설치하여 운영 중이며 그 외 매립지에서는 매립가스를 소각 또는 단순 대기 방출하여 대기오염유발과 동시에 대체에너지원 미활용으로 국가차원에서 큰 손실이므로 이를 활용할 수 있는 기술개발이 시급하다. 본 연구에서는 중소규모 매립지에서 발생하는 매립가스를 중심적환장으로 이송하여 경제성을 가지는 에너지원으로 활용할 수 있는 기술개발을 목표로 하이드레이트 기술을 접목한 기초연구를 수행하였다. 매립지에서 매립가스가 생성되는 과정에 표층부의 균열 및 차수막의 손상과 포집하는 공정에서 블로워 등의 사용으로 질소가 다량 포함되며 질소의 경우 상당히 높은 압력과 낮은 온도에서 하이드레이트를 형성하므로, 매립가스 하이드레이트 형성시 질소의 영향에 대해 알아보았다. $CH_4+CO_2$ System과 $CH_4+O_2+N$ System에 대하여 각각의 실험조건에서 Kinetic을 측정하였으며, 실험전후의 가스 조성을 Gas Chromatography로 정성, 정량 분석하였다. 실험결과 매립가스에 공기가 유입될 경우, 질소의 영향으로 하이드레이트 생성조건이 가압되었고 하이드레이트 내 메탄의 함량비율이 줄어들었다.