• Journal of Forest and Environmental Science
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• 제29권3호
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• pp.194-199
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• 2013

The aim of the present study was to assess the effect of transitional boundary on community composition and soil carbon stock. Five vegetation types were recognized horizontally along the transitional strip based on the dominance of tree species i.e., Pure Anogeissus latifolia forest (P.AL), mixed Pinus roxburghii and Lannea coromandelica forest (M.PR&LC), pure Pinus roxburghii forest (P.PR), mixed Pinus roxburghii and Lannea coromandelica (M.PR&LC) and pure Anogeissus latifolia forest (P.AL). The results revealed that Anogeissus latifolia was reported dominant tree in the outer transitional boundaries of the forest, which reduced dominance of trees towards middle where Pinus roxburghii was found dominant. The soil carbon stock was reported higher in the Anogeissus latifolia dominant forest and reduced with the dominance of Pinus roxburghii in the middle site. Both the species are growing close to one another and competing for survival, but the aggressive nature of Anogeissus latifolia particular in this region may change new growth of Pinus roxburghii and will enhance soil carbon stock. But high anthropogenic pressure on Anogeissus latifolia tree species could be limited chance to further its flourish.

• 한국농촌건축학회논문집
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• 제1권3호
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• pp.77-86
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• 1999

Recently the change of social environment has influence on the living of human for the complexity and the variety. And so the relation of architecture and function required the complex space. The government tried to complex the service for healthcare and social welfare by the exhibition model for health and welfare center. In this sence, this study aims to explore the basic data for the planning of location to the community welfare center and the healthcare facility in a district by grasping the difference of level at facility among region. In sum, the useful data were collected, analyzed, and synthesized through this study and could be used in the relevant research in the future as reference informations.

• Geomechanics and Engineering
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• 제21권5호
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• pp.471-487
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• 2020

In this work, the buckling analysis of material sandwich plates based on a two-parameter elastic foundation under various boundary conditions is investigated on the basis of a new theory of refined trigonometric shear deformation. This theory includes indeterminate integral variables and contains only four unknowns in which any shear correction factor not used, with even less than the conventional theory of first shear strain (FSDT). Applying the principle of virtual displacements, the governing equations and boundary conditions are obtained. To solve the buckling problem for different boundary conditions, Galerkin's approach is utilized for symmetric EGM sandwich plates with six different boundary conditions. A detailed numerical study is carried out to examine the influence of plate aspect ratio, elastic foundation coefficients, ratio, side-to-thickness ratio and boundary conditions on the buckling response of FGM sandwich plates. A good agreement between the results obtained and the available solutions of existing shear deformation theories that have a greater number of unknowns proves to demonstrate the precision of the proposed theory.

• Journal of Forest and Environmental Science
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• 제32권2호
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• pp.164-172
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• 2016

This study examined the recognition differences between local residents and national park managers on the adjustment of national parks which are conducted every ten years for the purpose of providing basic information for the park management, according to the Natural Parks Act. Both local residents and national park managers positively perceived the adjustment of national parks, but park managers showed concern towards the damage of natural resources resulting from the cancellation and adjustment of restricted development districts in Korean national parks. Local residents are more likely than park managers to recommend boundary adjustment in other national parks regarding the influence of parks adjustment on local change. While local residents recognized that the boundary adjustment of national parks improves the level of community management, park managers focused on damages on the local environment and the park landscape adjacent to the areas. The result shows the recognition differences of local residents and park managers. Further research into adjustment of national parks is necessary to diminish perception gaps among stakeholders and develop prediction indicators of cancellation effect in response to the future cancellation areas of national parks through the characteristics of cancellation communities, revitalization of local economy, and environmental change of local community.

• 대한토목학회논문집
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• 제35권5호
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• pp.1083-1096
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• 2015

본 연구는 준설매립과정에서의 관중혼합 거동을 3차원 전산유체역학(CFD, Computational Fluid Dynamics)을 통해 분석한 연구로 준설토 배송관과 개질재 주입관이 합류하며 발생되는 이상(2-phase)유체의 혼합효율을 사전 평가함으로써 관중혼합 양상을 고찰하는 물리실험의 시행착오를 줄여 경제성을 증진시키는데 연구목적을 두고 있다. 수치해석에 이용된 CFD 코드는 OpenFOAM$^{(R)}$이고, 몇 가지의 기본가정 하에 배송관-주입관의 관경과 합류각을 변화시켜 총 18가지 경우에 대한 삼상(3-phase)유체 거동을 모의하였다. 그 결과 혼합효율에 대한 우열은 있었으나 그 차이는 미미하였고, 모든 경우에서 각 재료 사이의 경계층이 뚜렷하게 형성되었다. 이러한 현상을 극복하기 위한 보완 실험을 통해 경계층 파쇄(破碎)를 위한 관 내 부속 구조물이 고안되었으며, 본 연구에서 제시된 구조물은 단거리 배송관로 내 준설토와 개질재의 혼합효율을 크게 향상시킬 수 있음을 확인할 수 있었다.

• 한국유통학회지:유통연구
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• 제14권1호
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• pp.1-25
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• 2009

본 연구의 목적은 소비자 관점에서 할인점의 사회적 책임 활동과 점포태도간의 관계를 실증함과 동시에 그러한 관계의 경계 조건으로 지역애착도의 조절효과를 규명하는데 있다. 1,118명의 할인점 이용 고객을 대상으로 수집된 자료가 분석에 이용되었으며, 분석 결과 사회공헌활동, 소비자보호, 환경보호와 같은 사회적 책임 활동이 점포태도에 영향을 미치는 것으로 나타났다. 아울러 지역사회공헌활동과 소비자보호는 지역애착도가 높은 소비자의 경우에 점포태도에 미치는 영향력이 증가하는 조절효과를 보여 주었다. 이러한 결과에 대한 이론적 및 실무적 시사점과 향후 연구 방향이 제시되었다.

• Nuclear Engineering and Technology
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• 제55권5호
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• pp.1911-1923
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• 2023

The nuclear safety assessment involving large transient simulations is forcing the community to develop methods for coupling thermal-hydraulics and neutronic codes and three-dimensional (3D) Computational Fluid Dynamics (CFD) codes. In this paper a set of dynamic boundary conditions are implemented in OpenFOAM^Ⓡ in order to apply zero-dimensional (0D) approaches coupling with 3D thermal-hydraulic simulation in a single framework. This boundary conditions are applied to model pipelines, tanks, pumps, and heat exchangers. On a first stage, four tests are perform in order to assess the implementations. The results are compared with experimental data, full 3D CFD, and system code simulations, finding a general good agreement. The semi-implicit implementation nature of these boundary conditions has shown robustness and accuracy for large time steps. Finally, an application case, consisting of a simplified open pool with a cooling external circuit is solved to remark the capability of the tool to simulate thermal hydraulic systems commonly found in nuclear installations.

• 한국환경과학회지
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• 제25권7호
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• pp.1029-1042
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• 2016

The initial and boundary conditions are important factors in regional chemical transport modeling systems. The method of generating the chemical boundary conditions for regional air quality models tends to be different from the dynamically varying boundary conditions in global chemical transport models. In this study, the impact of real time Copernicus atmosphere monitoring service (CAMS) re-analysis data from the modeling atmospheric composition and climate project interim implementation (MACC) on the regional air quality in the Korean Peninsula was carried out using the community multi-scale air quality modeling system (CMAQ). A comparison between conventional global data and CAMS for numerical assessments was also conducted. Although the horizontal resolution of the CAMS re-analysis data is not higher than the conventionally provided data, the simulated particulate matter (PM) concentrations with boundary conditions for CAMS re-analysis is more reasonable than any other data, and the estimation accuracy over the entire Korean peninsula, including the Seoul and Daegu metropolitan areas, was improved. Although an inland area such as the Daegu metropolitan area often has large uncertainty in PM prediction, the level of improvement in the prediction for the Daegu metropolitan area is higher than in the coastal area of the western part of the Korean peninsula.

• 한국경제지리학회지
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• 제7권2호
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• pp.157-170
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• 2004

경기도 접경지역은 저개발로 인해 청정한 환경을 유지해 왔으나 개발압력과 주민들의 개발 욕구로 인해 환경훼손에 취약한 지역이다. 이 논문은 경기 접경지역의 토지이용 변화패턴과 지역정서, 환경관리 기반시설의 현황을 분석하여 이 지역이 직면한 환경부하의 실태를 규명하고자 하였다. 분석 결과 김포, 파주, 동두천, 양주 등 서울과 근접한 서남부 접경지역을 중심으로 개발 압력이 높아지고 있으며, 토지규제 기반의 생태서식지 보전정책에 대한 저항 정서가 높은 것으로 드러났다. 한편 오염배출 시설의 입지가 서부 접경지역을 중심으로 높아지고 있으나 수질$.$폐기물 관련 환경관리 기반시설이 미비하여 환경훼손을 유발할 가능성이 높은 것으로 나타났다. 접경지역의 환경부하에 대한 체계적인 대책이 요청된다.

• 한국해안·해양공학회논문집
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• 제35권2호
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• pp.41-48
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• 2023

본 연구에서는 바닥의 움직임에 따른 파랑의 생성 및 변화를 모의할 수 있는 간단한 선형 수치해석 기법을 소개한다. 연속방정식과 선형의 동역학적 및 운동학적 자유수면 경계조건, 선형의 운동학적 바닥 경계조건을 공간에 대해 푸리에 변환한 후 파수 영역에서 수치해석을 수행하며, 결과는 푸리에 역변환을 통해 공간영역에서 표현된다. 파수 영역에서 동역학적 자유수면 경계조건과 운동학적 자유수면 경계조건이 수치적으로 계산되며, 이 때 평균수면 (z = 0)에서의 속도포텐셜은 연속방정식과 운동학적 바닥 경계조건을 만족한다. 삼각형 및 사각형 형상의 바닥이 주기적으로 움직이는 경우의 파랑 생성 및 전파에 대해 검토하였다. 간편 수치해석 기법을 이용한 결과는 기존의 선형 해석해와 비교하였으며, 거의 일치하는 결과를 보였다. 계산 시간간격(Δt)과 계산 파수간격(Δk)에 따른 수치해석 결과의 안정성에 대해서도 검토하였다. 검토 결과 Δt ≤T(주기)/1000, Δk ≤ π/100 일 때 수치해석에 의한 결과가 적절하게 도출되는 것으로 나타났다.