• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.641-642
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• 2015

Unlike for other building processes, BIM for earthwork does not need a large variety of 3D model shapes; however, it requires a 3D model that can efficiently reflect the changing features of the ground shape and provide soil type-dependent workload calculation and information on equipment for optimal management. Objects for earthwork have not yet been defined because the current BIM system does not provide them. The BIM technology commonly applied in the manufacturing center uses real-object data obtained through 3D scanning to generate 3D parametric solid models. 3D scanning, which is used when there are no existing 3D models, has the advantage of being able to rapidly generate parametric solid models. In this study, A method to generate 3D models for earthwork operations using reverse engineering is suggested. 3D scanning is used to create a point cloud of a construction site and the point cloud data are used to generate a surface model, which was then converted into a parametric model with 3D objects for earthwork

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2004년도 춘계학술대회 학술발표 논문집 제14권 제1호
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• pp.133-136
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• 2004

This paper proposes a stability condition in affine Takagi-Sugeno (T-S) fuzzy systems with parametric uncertainties and then, introduces the design method of a fuzzy-model-based controller which guarantees the stability. The analysis is based on Lyapunov functions that are continuous and piecewise quadratic. The search for a piecewise quadratic Lyapunov function can be represented in terms of linear matrix inequalities (LMIs).

• Journal of the Korean Data and Information Science Society
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• 제10권1호
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• pp.155-162
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• 1999

This paper is concerned with the empirical Bayes estimation of one of the two shape parameters(${\theta}$) in the Burr(${\beta},\;{\theta}$) type XII failure model based on type-II censored data. We obtain the bootstrap empirical Bayes confidence intervals of ${\theta}$ by the parametric bootstrap introduced by Laird and Louis(1987). The comparisons among the bootstrap and the naive empirical Bayes confidence intervals through Monte Carlo study are also presented.

• 자원ㆍ환경경제연구
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• 제22권2호
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• pp.281-307
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• 2013

조건부 가치측정법 연구에서 제시금액에 대한 지불의사가 없다는 영(0)의 지불의사 비중이 높을 경우 영의 지불의사를 밝히는 응답 자료들을 어떻게 처리해야 하는가를 두고 논란이 있다. 이에 본 연구에서는 이산화탄소 저감정책에 대한 설문조사결과를 활용하여 보다 합리적으로 영의 지불의사를 밝히는 응답 자료들을 처리할 수 있는 모형들을 비교 분석함으로써 학술적 시사점을 제공하고자 한다. 이를 위하여 본 연구에서는 스파이크모형을 포함한 혼합모형 등 모수적 추정법 뿐만 아니라 다양한 비모수적 추정법의 추정결과를 비교분석하고자 하였다. 분석결과, 모형에 따라서 다른 값들이 도출되었으며, 각각의 모형들의 한계점도 확인할 수 있었다. 이러한 점을 볼 때, 향후 CVM 연구에서는 특정 방법론을 이용하는 것 보다는 보다 보수적인 추정치를 제공하는 방법론을 이용하는 것이 적절한 것으로 판단된다.

• 응용통계연구
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• 제30권5호
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• pp.701-717
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• 2017

급속한 고령화로 인하여 미래의 인구와 인구구조에 관해 사회와 정부의 관심이 증가하고 있으며 우리나라의 사망률은 감소하고 있으나 감소폭은 변동적이다. 본 연구에서는 이를 고려할 수 있는 모형을 살펴보고자 LC 모형, LM 모형, BMS 모형 그리고 비모수평활 기법이 적용된 FDM과 Coherent FDM을 비교 분석하여 연령별 사망률과 기대수명 예측의 정확성 측면에서 남녀 사망률 개선 추이를 예측하는데 적합한 모형을 살펴보았다. 또한 우리나라 사망률 예측에 비모수 기법의 활용 가능성을 검토하였다. 분석 결과 최근 자료의 추세를 잘 반영하는 비모수기법을 활용한 인구통계모델인 FDM과 Coherent FDM의 예측력이 우수함을 알 수 있었다. 결과적으로 FDM과 Coherent FDM은 적합이 뛰어나고, 미래에 변화가 크지 않다면 예측력 또한 우수하다 볼 수 있을 것이다.

• 대한조선학회논문집
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• 제52권3호
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• pp.187-197
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• 2015

This study aims the development of a semi-analytic method for the parametric roll of large containerships advancing in longitudinal waves. A 1.5 Degree-of-Freedom(DOF) model is proposed to account the change of transverse stability induced by wave elevations and vertical motions (heave and pitch). By approximating the nonlinearity of restoring moment at large heel angles, the magnitude of roll amplitude is predicted as well as susceptibility check for parametric roll occurrence. In order to increase the accuracy of the prediction, the relationship between righting arm(GZ) and metacentric height(GM) is examined in the presence of incident waves, and then a new formula is proposed. Based on the linear approximation of the mean and first harmonic component of GM, the equation of parametric roll in irregular wave excitations is introduced, and the computational results of the proposed model are validated by comparing those of weakly nonlinear simulation based on an impulse-response-function method combined with strip theory. The present semi-analytic doesn’ t require heavy computational effort, so that it is very efficient particularly when numerous sea conditions for the analysis of parametric roll should be considered.

• 한국BIM학회 논문집
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• 제10권3호
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• pp.22-32
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• 2020

Apartment building site planning is one of time consuming and labor-intensive tasks in architectural design field, due to its complexity in zoning regulations, building codes, local restrictions, and site-specific conditions. In other words, the process can be seen as a very complicated mathematical function with layers of variables and parameters, which ironically can be automated using computational methods on parametric tools. In this paper, a practical method of automating site planning of an apartment complex has been proposed by utilizing parametric approaches in Rhino 3D and Grasshopper. Two primary parameters, building heights and positions, determine the efficacy of building layouts under all regulatory standards, thus testing out numerous combinations of the two will produce some successful layout alternatives. For this, equation solver has been used for iterating the parametric model to sort out meaningful results among others. It also has been proven that the proposed process significantly reduced the time in site planning down to less than an hour on most cases, and many successful alternatives could be obtained by using multiple computers. Post evaluation processes such as day light and view shed analysis helped sort out the best performing ones out of functioning alternatives.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집A
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• pp.894-899
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• 2000

An automatic mesh generation system with unstructured quadrilateral elements on trimmed NURBS surfaces has been developed.. In this paper, NURBS surface geometries in the IGES format have been used to represent model shape. NURBS surface is represented as parametric surface. So each surface could be mapped to a 2D parametric plane through the parametric domain. And then meshes with quadrilateral elements are constructed in this plane. Finally, the constructed meshes are mapped back to the original 3D surface through the parametric domain. In this paper, projection plane, quasi-expanded plane and parametric Plane are used as 2D mesh generation plane. For mapping 3D surface to parametric domain, Newton-Rhapson Method is employed. For unstructured mesh generation with quadrilateral elements on 2D plane, a domain decomposition algorithm using loop operators has been employed. Sample meshes are represented to demonstrate the effectiveness of the proposed algorithm.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 Ⅲ
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• pp.1411-1414
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• 2003

In this paper, vehicle tracking is implemented using parametric active contour. Extract objects from the background area is the essential step in vehicle tracking. We focus our algorithm on the situations such that the camera is fixed. However, if a simple and ordinary algorithm is adapted to achieve real-time processing, it produces much noise and the vehicle tracking results is poor. For this reason, in this paper, we propose a parametric active contour model algorithm to achieve better vehicle tracking. Experimental results show that the performance of the proposed algorithm is satisfactory.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1991년도 하계학술대회 논문집
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• pp.31-33
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• 1991

A passive power converter operating on the principle of parametric excitation, called Parametric transformer, is analyzed. The energy transfer from the input to the output is achieved through the double frequency variation of magnetic path reluctance to the input frequency without mutual flux coupling between two windings. Thus, output becomes available which is essentially independant of waveform of excitation. The mathmatical model of the device is developed and its solution is obtained. The outstanding characteristics of the device is explained from the analysis.