• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2003년도 추계학술대회
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• pp.271-276
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• 2003

In this study, we compared backpropagation neural network(BPNN) with probabilistic neural network(PNN) as shape recognition algorithm of welding flaws. For this purpose, variables are applied the same to two algorithm. Here, feature variable is composed of time domain signal itself and frequency domain signal itself, Through this process, we comfirmed advantages/disadvantages of two algorithms and identified application methods of two algorithms.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 B
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• pp.1024-1026
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• 2003

This paper deals with the characteristic analysis of round shape core of transformer compared with conventional EI core transformer. The round shape has specific configuration to reduce leakage magnetic flux. Characteristics such as B-H characteristic curve and in-rush current, etc. are compared.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 G
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• pp.3165-3168
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• 1999

When a input image is extensively magnified on the computer system, it is almost impossible to replicate the original shape because of mismatched coordinates system. In order to resolve the problem, the shape of the magnified image has been reconfigured using the bilinear interpolation method, low pass special filtering interpolation method and B-spline interpolation method. Ferguson curve interpolation method based on the CAD/CAM curve interpolation algorithm.

• 한국해양공학회지
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• 제11권1호
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• pp.36-43
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• 1997

Weld bead shape is an important measure for evaluation of weld quality. Many welding parameters have influence on the weld bead shape. The quantitative relationship between welding parameters and bead shape, however, is not determined yet because of their high complexity and many unknown factors. Fuzzy expert system is an advanced expert system which uses fuzzy rules and approximate reasoning. It is a vert useful tool for welding technology because is can process rationally the uncertain and inexact information such as the welding information. In this paper, the empirical and the qualitative relationship between welding parameters and bead shape are analyzed and represented by fuzzy rules. They are converted to the quantitative relationship by use of approximate reasoning of fuzzy expert system. Weld bead shape is estimated from the welding parameters using fuzzy expert system. The result of comparison between measured values of weld bead by welding experiments and the estimates values by fuzzy expert system shows a good consistancy.

• Journal of Electrical Engineering and Technology
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• 제7권3호
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• pp.330-335
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• 2012

The shape optimization of a Thomson coil actuator used in an arc eliminator is done for fast response by adopting topology modification method. The displacement of the plate in a fixed calculation time is taken as the objective function. The objective function and contribution factor are calculated by using an adaptive equivalent circuit method which has been proved accurate and efficient. Both shape optimization and performance analysis are accomplished based on the segmentation of plate. Through the refinement of the sensitive segments a precise optimal plate shape can be obtained. The effectiveness of the proposed method is proved by the comparison of results before and after the shape optimization.

• Journal of Electrical Engineering and Technology
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• 제7권1호
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• pp.58-63
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• 2012

The shape optimization of a Thomson coil actuator used in an arc eliminator is done for fast response by adopting topology modification method. The displacement of the plate in a fixed calculation time is taken as the objective function. The objective function and contribution factor are calculated by using an adaptive equivalent circuit method which has been proved accurate and efficient. Both shape optimization and performance analysis are accomplished based on the segmentation of plate. Through the refinement of the sensitive segments a precise optimal plate shape can be obtained. The effectiveness of the proposed method is proved by the comparison of results before and after the shape optimization.

• Nuclear Engineering and Technology
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• 제49권1호
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• pp.29-42
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• 2017

The purpose of the present study is the presentation of the appropriate element and shape function in the solution of the neutron diffusion equation in two-dimensional (2D) geometries. To this end, the multigroup neutron diffusion equation is solved using the Galerkin finite element method in both rectangular and hexagonal reactor cores. The spatial discretization of the equation is performed using unstructured triangular and quadrilateral finite elements. Calculations are performed using both linear and quadratic approximations of shape function in the Galerkin finite element method, based on which results are compared. Using the power iteration method, the neutron flux distributions with the corresponding eigenvalue are obtained. The results are then validated against the valid results for IAEA-2D and BIBLIS-2D benchmark problems. To investigate the dependency of the results to the type and number of the elements, and shape function order, a sensitivity analysis of the calculations to the mentioned parameters is performed. It is shown that the triangular elements and second order of the shape function in each element give the best results in comparison to the other states.

• 한국CDE학회논문집
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• 제11권4호
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• pp.315-325
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• 2006

It is very often necessary to search for similar parts during designing a new product because its parts are often easily designed by modifying existing similar parts. In this way, the design time and cost can be reduced. Thus it would be nice to have an efficient similarity comparison algorithm that can be used anytime in the design process. There have been many approaches to compare shape similarity between two solids. In this paper, two parts represented in B-Rep is compared in two steps: one for overall appearances and the other for detail features. In the first step, geometric information is used in low level of detail for easy and fast pre-classification by the overall appearance. In the second step, feature information is used to compare the detail shape in high level of detail to find more similar design. To realize the idea above, a multi resolution algorithm is proposed so that a given solid is described by an overall appearance in a low resolution and by detail features in high resolution. Using this multi-resolution representation, parts can be compared based on the overall appearance first so that the number of parts to be compared in high resolution is reduced, and then detail features are investigated to retrieve the most similar part. In this way, computational time can be reduced by the fast classification in the first step while reliability can be preserved by detail comparison in the second step.

• 한국멀티미디어학회논문지
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• 제12권4호
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• pp.492-501
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• 2009

동영상에서 객체의 동작 정보는 장면의 내용을 분류하고 구분하는 중요한 정보로 이용될 수 있다. 본 논문에서는 동영상에서 객체의 동작을 효과적으로 찾기 위한 모양기반 동작 검색 방법을 제안한다. 객체의 동작 정보는 동영상 프레임에서 객체 영역을 추출하여 연속된 2차원 모양 정보로 표현되고, 각각의 2차원 모양 정보는 모양 기술자를 이용하여 1차원 모양 특정값으로 변환된다. 순서에 따라 나열된 모양 기술자 시퀀스를 이용하여 개별 동작의 분할 과정 없이 문서에서 단어를 검색하듯이 동영상에서 객체의 동작을 검색할 수 있다. MPEG-7 모양 변화 기술자와의 성능 비교 실험을 통하여 제안된 방법이 객체의 동작 정보를 보다 효과적으로 표현할 수 있으며, 동작 검색 및 분석 응용에 적용할 수 있음을 보였다.

• 혜화의학회지
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• 제20권1호
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• pp.51-63
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• 2011

There are two methods in inspection diagnosis(望診), the viewing shape(觀形) and the inspecting color(察色). Acquiring proper analysis from viewing shape(觀形) requires several standards of shape that can be compared with. We can identify major defects and flaws of the shape from comparing it with the standards that is defined as very normal shape. Also, It can eventually provide us interpretation of health related meanings of the objective shapes. Those standards need symmetrical and proportional details. In this research, I put some physiognomy and inspection diagnosis related documents, and standards for restorative plastic surgery together to suggest standards on viewing shape diagnosis of nose which is one of the most important spot in facial inspection. It is expected to improve delicacy of Oriental medine's inspection diagnosis, as the result of the comparison between plastic surgery and inspection diagnosis.