• 한국의류학회지
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• 제29권11호
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• pp.1507-1519
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• 2005

The purpose of this study was to compare two methods of measuring body surface area (BSA). The BSA of Korean adults was measured using both three-dimensional (3D) scanning and an alginate method. Two males (one overweight and one lean) and one overweight female participated as subjects. The results were as follows: First, the 3D scanned BSA of all three subjects was smaller than the BSA measured using the alginate method by as much as $6-14\%$. The difference in methods was greater in the overweight participants than in the lean subject. Second, the results comparing the BSA obtained using these two methods and the BSA estimated by 10 previously developed formulas, showed that the 3D scanned BSA was the smallest among the 12 BSAs. Third, in comparing the regional differences between these two methods, the regional BSA of the lean subject (male 2) did not show any significant difference, but the overweight subjects (male 1, female 1) showed a significant difference. Forth, the biggest difference in regional BSA obtained through these two methods was in the hand, for all three subjects. The 3D scanned hand surface area was smaller than the hand surface area measured by the alginate method by as much as $24-34\%$. Fifth, in the percentage of regional BSA, there was no significant difference in these two methods. The reasons for the underestimation in the 3D scanning might be because: 1) the 3D scanner can not recognize the folding and shading of body parts, such as the finger, toe, ear, armpit, crotch and breast, 2) 3D patching and smoothing processes depend on researchers. However, the 3D scanning method is applicable to the estimation of the entire BSA, if the surface area of the hands is known, and the participant is not overweight.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2012년도 추계학술대회
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• pp.447-449
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• 2012

사실적인 3D game을 만들기 위해 여러 가지 필수 요소가 있는데, 그 중 큰 비중을 차지하고 있는 것이 바로 mapping이다. Mapping은 모델링만으로 감당할 수 없는, 혹은 감당하기 힘든 디테일을 쉽게 추가할 수 있으며 파일의 용량을 줄여 게임 엔진 상에 구현하는데 부하를 줄여줄 수 있다. Mapping의 원리는 3D object에 2D 이미지를 정확히 투영시키는 것인데, 2D와 3D의 기본적 속성 차이 때문에 100% 1:1 매치가 되지 않는다는 문제가 있다. 이를 해결하기 위해 각종 mapping 방법이 개발되고 사용되고 있다. 본 논문에서는 이런 각종 Mapping 방법의 특징과 장단점에 대해 비교 분석하고 어떤 방법이 game개발에 있어서 가장 효율적인지 알아보도록 하겠다.

• 한국의류학회지
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• 제44권2호
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• pp.193-208
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• 2020

This study investigated similarities and differences between 2D flat sketch, 3D virtual clothing and real clothing images. Flat sketch, 3D virtual clothing, and real clothing images of T-shirts and dresses were made. Questionnaires were prepared for fit evaluation, sensory evaluation, and location evaluation. A survey of 440 questionnaires was collected from Chinese women in their 20s and 30s. As results of the sensibility evaluation, 3D virtual clothing expressed real clothing images slightly more similar than a 2D flat sketch. As results of the fit evaluation of the dresses, 2D flat sketch and 3D virtual clothing were rated as slightly longer/wider, and real clothing images were rated as slightly shorter/narrower. The results suggested that presenting 3D images with avatars as 3D virtual clothing images will provide more accurate fit evaluation results. This study presented possibilities and methods for apparel companies to utilize 3D system as an effective apparel production tool.

• 대한치과교정학회지
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• 제42권4호
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• pp.169-181
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• 2012

Objective: The purpose of this study was to develop superimposition method on the lower arch using 3-dimensional (3D) cone beam computed tomography (CBCT) images and orthodontic 3D digital modeling. Methods: Integrated 3D CBCT images were acquired by substituting the dental portion of 3D CBCT images with precise dental images of an orthodontic 3D digital model. Images were acquired before and after treatment. For the superimposition, 2 superimposition methods were designed. Surface superimposition was based on the basal bone structure of the mandible by surface-to-surface matching (best-fit method). Plane superimposition was based on anatomical structures (mental and lingual foramen). For the evaluation, 10 landmarks including teeth and anatomic structures were assigned, and 30 times of superimpositions and measurements were performed to determine the more reproducible and reliable method. Results: All landmarks demonstrated that the surface superimposition method produced relatively more consistent coordinate values. The mean distances of measured landmarks values from the means were statistically significantly lower with the surface superimpositions method. Conclusions: Between the 2 superimposition methods designed for the evaluation of 3D changes in the lower arch, surface superimposition was the simpler, more reproducible, reliable method.

• 한국정보과학회논문지:소프트웨어및응용
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• 제32권1호
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• pp.34-40
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• 2005

엔지니어링 정보와 같은 3차원 정보의 시각화에는 CAD, 2D 컴퓨터그래픽, 3D 컴퓨터그래픽, 가상현실(VE)을 이용한 3차원적 표현 등 다양한 정보표현방식이 이용될 수 있으나, 이들 방식의 효과에 대한 비교연구는 매우 부족하다. 본 연구의 목적은 CAD, 2D 컴퓨터그래픽, 3D 컴퓨터그래픽, 가상현실의 한 형태인 증강현실 방식(AR)의 정보표현 방식에 대한 사용자의 호의도 및 심리적, 신체적 업무부하의 차이를 비교하는 것이다. 실험결과 사용자들은 정보제공방식 간에 업무부하의 차이는 없다고 보고하였으나, 2D 정보표현보다 3D 정보표현을 선호하였다 우리가 물체를 인식하는 방식과 동일한 방식으로 정보를 제공하는 AR방식은 인식정보의 병렬처리를 통하여 엔지니어링 정보제공에 유용한 수단으로 사용될 수 있음을 보여 주었다.

• Spatial Information Research
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• 제21권2호
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• pp.73-83
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• 2013

최근 몇 년 사이 3차원 지적에 대한 관심과 관련 연구가 증가하고 있다. 그러나 아직까지는 입체적인 토지 이용과 이를 둘러싼 다양한 권리문제에 대한 정확한 개념이 정립되지 못하고 있으며, 이는 3차원 지적의 적절한 구현과 운영방안의 부재에서도 그 이유를 찾아볼 수 있다. 2차원 지적보다도 더욱 방대한 데이터가 필요한 3차원 지적은 DBMS에 기반하여 구현되어야 하며 이를 위한 적절한 방법론과 프로세스가 필요하다. 본 연구에서는 DBMS를 위한 3차원 지적의 모델링 방법에 대해 제시한다. 먼저 3차원 공간상에서 존재하는 다양한 형태의 구분지상권에 대해 가시적으로 분석한다. 이를 이용하여 UML에 기반한 모델을 예시한 후 관계형 데이터베이스 시스템(RDBMS)을 이용해서 구현하기 위한 O-R Mapping 과정을 제시한다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제16권9호
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• pp.2991-3007
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• 2022

Two dimensional locality preserving projections (2D-LPP) is an improved algorithm of 2D image to solve the small sample size (SSS) problems which locality preserving projections (LPP) meets. It's able to find the low dimension manifold mapping that not only preserves local information but also detects manifold embedded in original data spaces. However, 2D-LPP is simple and elegant. So, inspired by the comparison experiments between two dimensional linear discriminant analysis (2D-LDA) and linear discriminant analysis (LDA) which indicated that matrix based methods don't always perform better even when training samples are limited, we surmise 2D-LPP may meet the same limitation as 2D-LDA and propose a novel matrix exponential method to enhance the performance of 2D-LPP. 2D-MELPP is equivalent to employing distance diffusion mapping to transform original images into a new space, and margins between labels are broadened, which is beneficial for solving classification problems. Nonetheless, the computational time complexity of 2D-MELPP is extremely high. In this paper, we replace some of matrix multiplications with multiple multiplications to save the memory cost and provide an efficient way for solving 2D-MELPP. We test it on public databases: random 3D data set, ORL, AR face database and Polyu Palmprint database and compare it with other 2D methods like 2D-LDA, 2D-LPP and 1D methods like LPP and exponential locality preserving projections (ELPP), finding it outperforms than others in recognition accuracy. We also compare different dimensions of projection vector and record the cost time on the ORL, AR face database and Polyu Palmprint database. The experiment results above proves that our advanced algorithm has a better performance on 3 independent public databases.

• Journal of Oral Medicine and Pain
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• 제20권2호
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• pp.497-513
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• 1995

Human genomic Deoxyribonucleic acid(DNA) was extracted from teeth by boiling, salting-out, phenol, boiling-phenol methods. The author compared DNA concentration and its purity, the accuracy of sex determination and the results of the D1S80 locus detection among above 4 methods. The following results were obtained : 1. DNA concentration was the highest in pulp with salting-out method and DNA purity was higher in pulp with salting-out and phenol methods than other 2 methods. 2. Sex determination was possible using of the pulp and the dentin of the teeth with four methods but, it was impossible in the enamel and some pulp with boiling method. 3. Amplification of D1S80 locus occurred from pulp and dentin with salting-out, phenol, and boiling-phenol methods. 4. There are no differences among the amplification of X-Y homologus amelogenin gene by application of 4 methods and salting-out, phenol methods efficiently makes available to amplification of D1S80 locus. From the investigation DNA extraction, sex determination, amplification of D1S80 locus was successfully accomplished with salting-out, phenol, boiling-phenol methods Therefore above 3 methods are available and applicable as forensic odontology for individual identification.

• 한국정보통신학회논문지
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• 제13권12호
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• pp.2693-2700
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• 2009

본 논문에서는 렌즈 배열에 의한 대용량의 3차원 집적 영상을 활용하기 위한 효율적인 압축 방법을 제안한다. 기존의 정지영상 압축 기법은 각 요소 영상간의 상관도를 적절하게 제거하지 못하여 압축 효율 및 화질 측면에서 낮은 성능을 보인다. 또한, 각 요소 영상을 1차원 스캔방법에 의해 분리하여 동영상 압축기법을 이용할 경우 요소 영상간 상관도를 효과적으로 제거하는 데 한계가 있다. 제안하는 방식에서는 2차원 참조기법에 의해 각 요소 영상을 분리하고, 이를 H.264/AVC의 다중 프레임 참조 기법을 이용하여 효과적으로 압축한다. 제안하는 2차원 참조 기법은 요소 영상의 수직, 수평 및 대각 방향의 상관도에 따라 최적의 참조 영상을 선택할 수 있어 가장 좋은 압축성능을 나타낸다. 실험 결과는 정지 영상 압축 방법에 비해 요소 영상을 분리하는 방법이 압축 성능을 향상시킴을 보이고, 제안하는 2차원 참조 기법이 1차원 스캔 방식에 비해 주관적 화질 및 객관적 성능에 있어 뛰어남을 보인다.

• Current Optics and Photonics
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• 제6권2호
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• pp.161-170
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• 2022

Three-dimensional (3D) geometric models are introduced to correct vignetting, and a downhill simplex search is applied to determine the coefficients of a 3D model used in digital microscopy. Vignetting is nonuniform illuminance with a geometric regularity on a two-dimensional (2D) image plane, which allows the illuminance distribution to be estimated using 3D models. The 3D models are defined using generalized polynomials and arbitrary coefficients. Because the 3D models are nonlinear, their coefficients are determined using a simplex search. The cost function of the simplex search is defined to minimize the error between the 3D model and the reference image of a standard white board. The conventional and proposed methods for correcting the vignetting are used in experiments on four inspection systems based on machine vision and microscopy. The methods are investigated using various performance indices, including the coefficient of determination, the mean absolute error, and the uniformity after correction. The proposed method is intuitive and shows performance similar to the conventional approach, using a smaller number of coefficients.