• Journal of the Korean Geographical Society
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• v.35 no.2
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• pp.351-364
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• 2000

1980년 설치 이후 환경부는 환경정책과 환경관리에 대한 주요 업무 중의 하나로 자연환경의 보전에 주안점을 두고 있다. 또한 자연환경보전법에 의거하여 환경부는 자연환경상태에 대한 전국 단위의 자연환경조사를 실시하고 있다. 제1차 전국자연환경조사는 이미 1986-1990년에 실시하였고, 현재 교수 및 연구진의 참여 하에 제2차 전국자연환경조사(1997-2002)ff 실시하고 있다. 제2차 조사에서는 지형경관에 대한 조사가 포함되어 모든 종류의 지질 및 지형환경에 대한 조사가 이루어진다. 예를 들면 호수와 습지, 해안, 하천, 산지. 평야, 주빙하지형, 화산, 카르스트 및 구조지형 등이다. 조사지역은 육지 206개 소권역, 해안 145개 지점으로 나누고 6년에 걸쳐 매년 약 30개의 팀이 이 프로젝트에 참여하고 있다. 조사결과는 “지형경관도”로 편집, 인쇄될 예정이며 현존식생도, 동식물분포도와 함께 생태자연도로 작성될 예정이다. 제2차 조사에서 얻어진 방대한 양의 환경정보를 합리적이고 효율적으로 이용하기 위해서 환경부는 한경관리를 위한 이용과 응용에 환경정보시스템을 구축하고 있다.

• Bulletin of Korea Environmental Preservation Association
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• v.19 no.8
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• pp.64-69
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• 1997

• Korean Architects
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• no.9 s.245
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• pp.60-67
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• 1989

• Journal of KIISE:Software and Applications
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• v.34 no.4
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• pp.368-376
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• 2007

How to represent the search space is as important as which search algorithm to use for finding natural-looking paths for moving NPC (non-player character) in computer games. Recently, various state space representation methods which have been developed for computer games are being used while A* algorithm dominates as the preferred search algorithm. These representation methods show some drawbacks such as the size of state space is too large, there is no guarantee for optimality, the path found is not natural-looking, and the generation of nodes and links is not automatic by depending on a level designer. In this paper the requirements for natural-looking paths are introduced and to find paths satisfying these requirements, the use of the generalized visibility graphs which is the extended version of the visibility graph in Robotics is proposed.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.8
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• pp.739-747
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• 2010

Numerical calculations are carried out for evaluating the natural convection induced by the temperature difference between a hot inner circular cylinder and a cold outer square enclosure. A two-dimensional solution for unsteady natural convection is obtained by using the finite volume method to model an inner circular cylinder that was designed by using the immersed boundary method (IBM) for a Rayleigh number of $10^7$. In this study, we investigate the effect of the location ($\delta$) of the inner cylinder, which is located along the vertical central axis of the outer enclosure, on the heat transfer and fluid flow. The natural convection changes from unsteady to steady state depending on the $\delta$. The two critical lower bound and upper bound positions are ${\delta}_{C,L}$ = 0.05 and ${\delta}_{C,U}$ = 0.18, respectively. Within these defined bounds, the thermal and flow fields are in steady state.

• Fire Science and Engineering
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• v.15 no.4
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• pp.34-40
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• 2001

The spontaneous ignition of hydroxypropyl methyl cellulose(HPMC) was investigated at constant ambient temperature in the oven and minimum ignition temperature of dust clouds with Godbret-Creenwald Furnace respectively, In the experiments of the vessel filled with sample. the larger the vessel was the lower the spontaneous ignition temperature and ambient temperature was calculated from the Frank-Kamenetskii thermal ignition theory. The minimum ignition temperature for the dust cloud state was found under 21% oxygen concentration. At the experiment with the change of oxygen concentration, HPMC was not ignite at 10% $O_2$and so the limiting oxygen concentration was obtained at 10%.

• The Microorganisms and Industry
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• v.16 no.3
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• pp.44-47
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• 1990

Avery, MacLeod, McCarty가 1944년에 세균에서 유전적 재조합이 이루어진다는 사실을 발견한 후 세균은 진화 학자들과 미생물 학자들로 부터 주목을 받기 시작했다. 왜냐하면 세균은 자연생태계에서 또다른 형태의 유전적 적응성을 지니고 그러한 돌영변이 중 일부는 모세포(parent cell)보다도 주변환경에 더 잘 적응되었기 때문이다. 이제까지 GEM들이 생태계에서 유전자들 전이시키는 빈도가 대부분 낮았고, 토양이나 다른 자연생태계애서 유전자의 전이가 지속적으로 일어난다는 실험적 증거는 없었지만 이들을 생태계에 방출한 결과 유전자 전이가 몇몇 실험에서 확인된 적이 있어 토양에서의 유전적 전이의 가능성을 강하게 암시하고 있다. 하지만 어떻게 전이되고 토양의 물리, 화학및 전이에 필요한 최소한의 donor와 recipient의 수와 정확한 감지 방법등이 아직까지 밝혀져 있지 않은 상태이다. 더우기 토양환경에서 미생물의 활성과 생태, 군집 동태에 영향을 줄 수 있는 기능을 나타내려면 얼마만큼의 재조합 세균이 단위면적당 필요한지도 밝혀지지 않은 상태이다. 따라서 이러한 여러가지 문제점을 밝히는 것은 학문적인면 뿐만 아니라 진화론적인 이론에도 도움이 되며 GEM들이 토양이나 다른 생태계에 유출되었을 때의 환경영향평가나 규제를 하는데에도 도움이 될 수 있다고 본다.

• Korean Journal of Environment and Ecology
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• v.24 no.4
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• pp.351-362
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• 2010

This study was supposed to offer vegetation plans for functional improvement of the recreational forest by researching Mt. Chukryong which is located at Oebang-li Sudong-Myon Namyangju Kyong-gi Province in Korea. In this study, artificial vegetation and natural vegetation near trails in recreational forest were researched through biodiversity analysis. From this analysis process, a typical management improvement of the biodiversity functions were examined by reviewing functions biotope condition, vegetation structure and wild bird community condition. Typical vegetation system was divided into four detail parts: Managed artificial Pinus koraiensis forest, Not managed artificial Pinus koraiensis forest, Natural deciduous forest and Not managed deciduous forest. As a result of the vegetation structure, the numerical value of the deciduous forest species diversity was higher than that of artificial Pinus koraiensis, and the numerical value of the managed condition was higher than that of not managed condition. As a result of a habitat structure analysis of the wild bird community, managed Pinus koraiensis forests were inadequate structure for wild birds to habit in there because the forests had weak structure layers, but unmanaged deciduous forest and unmanaged Pinus koraiensis that had diverse layers was proper places for birds to in habit. Thus, based on the functional analysis of biodiversity, management patterns of the target area were concluded in two manners: conserving management and restoring management. Deciduous forest protection target areas included natural deciduous forest area and managed deciduous forest area, ecological restoration target area included unmanaged artificial Pinus koraiensis area and restoring management target area includes managed artificial Pinus koraiensis.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.514-514
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• 2013

플라즈마와 혈액의 상호작용 특성을 파악하기 위해 혈액응고 실험을 하였다. 생체에 적용 가능한 바이오 플라즈마 소스를 개발하여 다양한 조건으로 혈액에 플라즈마를 조사하였다. 혈액 응고의 정량적인 측정 방법으로 혈액의 저항을 측정하였다. 본 실험에 사용된 플라즈마 제트 장치는 의료용 바늘과 유리관, 외부 접지로 이루어져 있다. 플라즈마 제트 장치는 고전압 전극이 유리관 안에 위치하고 접지 전극이 유리관 바깥에 위치한다. 의료용 바늘을 통해 Ar gas를 주입하며, 약 2 kV의 전압을 인가하여 방전시켰다. 자연적으로 혈액을 응고시킨 경우, 칼슘 클로라이드를 첨가하여 응고시킨 경우, Ar gas 및 온풍을 단독적으로 불어넣은 경우, 그리고 플라즈마 제트를 조사한 경우로 나누어 실험을 진행하였다. 두개의 떨어진 전극 사이에 일정량의 혈액을 배치시켜 저항을 측정하여 응고 정도를 파악하였다. 플라즈마 제트를 조사하였을 경우 아무것도 처리하지 않은 자연상태의 혈액보다 혈액이 응고되는 속도가 빠르게 나타났다. Ar gas와 온풍을 단독으로 불어넣어 준 경우와 혈액 표면이 응고되었으나, 약 20초가 지나면 다시 원래 상태의 혈액으로 돌아감을 확인하였다. 플라즈마 제트를 혈액에 조사했을 때는 혈액이 이전의 혈액 상태로 돌아가는 경향이 나타나지 않았다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.7
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• pp.4072-4080
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• 2014

The Peltier Module has been used to dissipate the heat from electronic devices and electronic components. In this module, a heat sink is used to release the operating heat into the air outside. This study addressed the heat transfer characteristics for a heat sink with an inner tunnel. Under forced and natural convection conditions, the heat transfer characteristics were different. Therefore, the cooling and heating performances were studied for the heat sink, which has an inner tunnel. The heat transfer conditions were also evaluated by performing an experimental test, which investigated the heat transfer characteristics related to the variance in time and temperature distribution. Experiments on the heat transfer characteristics of the heat sink were conducted based on the forced and natural convection and temperature distribution changes. In the cooling experiment, the A- and B-shaped cooling pin heat sinks decreased the temperature of the forced convection than the temperature of natural convection. In the forced and natural convection, the A- and B-shaped decreased to a minimum of $-15^{\circ}C$. Under the forced and natural convection conditions, A- and B-shaped cooling pin heat sinks decreased the temperature when the voltage was increased. In the heating experiment, the A- and B-shaped cooling pin heat sinks increased the temperature of the forced convection than the temperature of natural convection. In forced convection, when the voltage was $15^{\circ}C$, the temperature of the A-shaped cooling pin heat sink increased to $150^{\circ}C$, and the temperature of the B-shaped cooling pin heat sink increased to $145^{\circ}C$. Under forced and natural convection conditions, the A- and B-shaped cooling pin heat sinks showed an increase in temperature with increasing voltage.