• Journal of Forest and Environmental Science
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• 제24권3호
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• pp.119-126
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• 2008

Growth and yield prediction methods, ranging from whole-stand models to individual-tree models, have been developed for forest types managed for wood production. The resultant models are used for a host of purposes including inventory updating, management planning, evaluation of silvicultural alternatives, and harvest scheduling. Because of the large investment in developing growth and yield models for improved genotypes and silvicultural practices for loblolly pine (Pinus taeda) in the Southern United States, this region serves to illustrate approaches for modelling intensively managed forests. Analytical methods and computing power generally do not restrict development of reliable growth and yield models. However, long-term empirical observations on stand development, which are time consuming and expensive to obtain, often limit modelling efforts. Given that growth and yield models are used to project present volumes and to evaluate alternative treatment effects, data of both the inventory type and the experimental type are needed. Data for developing stand simulators for loblolly pine plantations have been obtained from a combination of permanent plots in operational forest stands and silvicultural experiments; these data collection efforts are described and summarized. Modelling is essential for integrating and synthesizing diverse information, identifying knowledge gaps, and making informed decisions. The questions being posed today are more complex than in the past, thus further accentuating the need for comprehensive models for stand development.

• 한국자동차공학회논문집
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• 제23권3호
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• pp.254-262
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• 2015

This paper presents 3D collision deformation modelling methodologies using photogrammetry for reconstruction of vehicle accidents. A vehicle's deformation shape in collision provides important information on how the vehicle collided. So effective measurement(scanning) and construction of a corresponding appropriate model are essential in the analysis of collision deformation shape for obtaining much information related to collision accident. Two measurement methods were used in this study: Indirect-photogrammetry which requires relatively small amount of photos or videos, and direct-photogrammetry which requires large amount of photos directly taken for the purpose of 3D modelling. When the indirect-photogrammetry method, which was mainly used in this study, lacked enough photographic information, already secured 2D numerical deformation data was used as a compensation. This made 3D collision deformation modelling for accident reconstruction analysis possible.

• 한국가구학회지
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• 제10권2호
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• pp.79-86
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• 1999

본 연구는 국내가구 디자인 산업의 경쟁력 강화를 위한 사례의 하나로 디자인 작품을 시도하게 되었다. 지존의 디자인 모델링은 소프트 모델 또는 목업(mock up)개념에서 시행되어 디자이너가 직접 제작하기 전에는 3차원의 형상을 구현하기가 어려웠으며, 더욱이 문야의 적용은 실크스크린 또는 인쇄와 같은 처리기법으로 사용되었다. 이 방법은 시간, 경비, 공간, 자료의 보관 및 축적, 기타의 많은 문제점과 생산성 향상에 애로사항이 되어왔다. 요지와 같이 많은 문제점과 렌더링의 데이터베이스 뱅크는 활용 가능한 분야와 직종에 따라서 응용 가능하기 때문에 많은 실험적 시도가 요구된다. 디자인의 발상은 우리나라 전통문화의 가구디자인을 접목시킨 사례로서 시도하였으며, 형태와 문양을 현대적 개념에서 재해석하여 대입시켰다. 적용디자인 사례는 2개의 모델에 10가지의 패턴을 복합적으로 활용한 디자인 작품의 결과물이다. 이러한 결과는 다양한 디자인 연출과 시안을 추출할 수 있으며, 디자인 활동과 설계에 능률을 배가시키는 효과를 검증할 수 있겠다.

• 한국해양공학회지
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• 제10권1호
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• pp.65-74
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• 1996

Up to now, the existing crack growth modelling has used a mathematical approximation but an assumed function have a great influence on this method. Especially, crack growth behavior that shows very strong nonlinearity needed complicated function which has difficulty in setting parameter of it. The main characteristics of neural network modelling to engineering field are simple calculations and absence of assumed function. In this paper, after discussing learning and generalization of neural networks, we performed crack growth modelling on the basis of above learning algorithms. J'-da/dt relation predicted by neural networks shows that test condition with unlearned data is simulated well within estimated mean error(5%).

• Journal of the Korean Data and Information Science Society
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• 제13권2호
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• pp.97-104
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• 2002

K-Means modelling has been tried for finding major DNA marker of ILST035 microsatellite loci in Hanwoo Chromosome 6 linkage map. Major DNA markers are obtained from the ILST035 microsatellite through quantitative trait loci(QTL) and data mining modelling.

• 대한의용생체공학회:의공학회지
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• 제9권1호
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• pp.17-24
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• 1988

This paper describes a neural network modelling of a vertebrate retina using a discrete-time and discrete-space approach based on neuro-anatomical data, and the computer simulations of the model which approximate the frog/amphibian negro-physiological data. It then compares them and describes how such a model can be beneficially used for confirming the hypothesis of a given neural system and further predict yet unknown experimental data.

• 터널과지하공간
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• 제24권2호
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• pp.131-142
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• 2014

본 연구는 정확한 단차부여가 가능한 전자뇌관을 사용하여, 모델링을 통한 진동예측과 실제 발파진동의 결과를 상호 비교함으로써 발파 작업 시 발생하는 진동을 예측하고 설계에 반영할 수 있는지의 가능성을 연구하였다. 모델링의 회귀분석 결과와 실제 획득한 진동 데이터의 회귀분석 결과를 비교하여 볼 때 유사성이 있는 것으로 확인되었고, 따라서 다양한 조건에서의 진동 추정이 보다 정밀성을 가질 수 있을 것으로 기대된다.

• Nuclear Engineering and Technology
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• 제44권8호
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• pp.871-888
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• 2012

This paper aims at presenting the state of the art, the recent progress, and the perspective for the future, in the modelling of two-phase flow in the horizontal legs of a PWR. All phenomena relevant for safety analysis are listed first. The selection of the modelling approach for system codes is then discussed, including the number of fluids or fields, the space and time resolution, and the use of flow regime maps. The classical two-fluid six-equation one-pressure model as it is implemented in the CATHARE code is then presented and its properties are described. It is shown that the axial effects of gravity forces may be correctly taken into account even in the case of change of the cross section area or of the pipe orientation. It is also shown that it can predict both fluvial and torrential flow with a possible hydraulic jump. Since phase stratification plays a dominant role, the Kelvin-Helmholtz instability and the stability of bubbly flow regime are discussed. A transition criterion based on a stability analysis of shallow water waves may be used to predict the Kelvin-Helmholtz instability. Recent experimental data obtained in the METERO test facility are analysed to model the transition from a bubbly to stratified flow regime. Finally, perspectives for further improvement of the modelling are drawn including dynamic modelling of turbulence and interfacial area and multi-field models.

• 한국산학기술학회논문지
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• 제13권12호
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• pp.5716-5720
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• 2012

현재 산업체에서 그 수요가 늘어나고 있는 3차원 제품 모델과 관련하여 군에서의 3차원 모델 활성화 방안을 연구하였다. 우리 군은 전통적으로 기계분야 중심의 제조업이 활성화되어 있어 기본적으로 2차원 도면을 기반으로 한 제품 설계가 주를 이루고 있으며, 이에 관련 지침 또한 2차원 도면 형태의 자료에 대해서만 규정하고 있다. 따라서 본 연구에서는 '국방규격 서식 및 작성에 관한 지침'으로 대표되는 현재 우리 군에서의 기술자료 관리 지침을 분석하고, 제품의 수명주기관리(Product Lifecycle Management) 관점에서 우리 군에서의 3D 제품모델 활성화를 위한 방안을 모색하고자 하였다.

• 지구물리
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• 제8권3호
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• pp.153-157
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• 2005

A discussion of a method has been used with success in terrain modelling to estimate the height at any point on the land surface from irregularly distributed samples. The special requirements of terrain modelling are discussed as well as a detailed description of the algorithm and an example of its application.