• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1995년도 추계학술대회 논문집
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• pp.1173-1176
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• 1995

We design and analyze two type stators for brushless DC linear motors by the experiment and the computational analysis. For a U-shape stator, the maximum manetic flux density by the finite element method(FEM) is large than that by the experiment by 1.0~2.2%. The result by the FEM is so accurate that it can be applied to the geometric design for the optimization. To increase the maximum magnetic flux density, we suggest an improved stator and analyze it by the 3-D and 2-D models. The maximum magnetic flux density of the improved stator is large than that of the U-Shape stator by 2.7%. Considering the size of the improved stator and maximum magnetic flux density, we determine that the optimized thickness is 5mm for a given specification.

• 한국CDE학회논문집
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• 제18권5호
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• pp.367-373
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• 2013

In this study, the penetration characteristic from the cubic and cylindrical penetrator consisting of tungsten material with the velocity of 2,300 m/s is evaluated and the penetration possibility into the target is confirmed. The design of shape and size of penetrator is directly related to space and weight of the warhead. AUTODYN-3D simulation is used to study the penetration effect of penetrator. The purpose of numerical analysis is to verify the penetration characteristic with various L/D penetrator. The penetration performance of penetrator with identical weight due to the shape is also confirmed. The cylindrical and cubic penetrator has enough penetration energy on constant target body. Because the possibility of 2'nd penetration is important factor after 1'st penetration into target body, residual velocity of residual mass must be existed as much as possible. As geometrical shape ratio increases, penetration performance is confirmed to improve.

• 한국정보전자통신기술학회논문지
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• 제15권4호
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• pp.237-242
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• 2022

관제 및 측정 시스템 등에서 고품질 영상을 획득하는 것은 중요한 요소 중 하나이다. 영상 획득 기술 중에서 SFF (Shape from Focus)는 물체를 광축 방향으로 사전에 결정된 스텝 사이즈로 이동시킴으로써 초점 정도가 다른 2D 영상들을 획득함으로써 삼차원 형상을 복원하는 기술이다. SFF를 위해 일정한 스텝 사이즈로 물체를 이동시킬 때 각 스텝에서 광축 방향으로 기계 진동, 즉 지터 노이즈가 발생한다. 본 논문에서는 이 지터 노이즈의 영향을 줄이기 위해 새로운 상태 추정 필터를 설계 및 적용한다. 제안된 방법의 적용을 위해 지터 노이즈와 초점 커브는 가우시안 함수로써 모델링한다. 실험 결과들을 통해 제안된 방법의 효율성을 증명한다.

• Nuclear Engineering and Technology
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• 제55권12호
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• pp.4678-4684
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• 2023

Using the Monte Carlo method, the impact of the angular distribution of the electron source on the dose distribution for the 2.5 MeV ELV electron accelerator was explored. The experiment measured the 3-D dose distribution in the irradiation chamber for electron energies of 1.0 MeV and 2.5 MeV. The simulation used the MCNP6.2 code to evaluate three angular distribution models of the source: a mono-directional beam, a cone shape, and a triangular shape. Of the three models, the triangular shape with angles θ = 30°, φ = 0° best represents the angle of the scan hood through which the electron beam exits. The MCNP6.2 simulation results demonstrated that the triangular model is the most accurate representation of the angular distribution of the electron source for the 2.5 MeV ELV electron accelerator.

• 사상체질의학회지
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• 제18권2호
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• pp.41-49
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• 2006

1. Objectives The Face is an important standard for the classification of Sasang Contitutions. We are developing 3D Face Automatic Recognition Apparatus to analyse the facial characteristics. So We should examine a shape demobilization error of 3D Face Automatic Recognition Apparatus. 2. Methods We compared facial shape data be demobilized by 3D Face Automatic Recognition Apparatus with facial shape data that be demobilized by 3D laser scanner. The subject was two korean men. And We analysed the average error and the maximum error of two data. In this process, We used one datum point(the peak of nose) and two datum line(vertical section and horizontal section). 3. Results and Conclusions In each this comparison, the average error of vertical section was 1.962574mm and 2.703814mm. and the maximum error of vertical section was 16.968249mm and 18.61464mm. the average error of horizontal section was 4.173203mm and 21.487479mm. and the maximum error of horizontal section was 3.571210mm and 17.13255mm. Also We complemented this apparatus a little and We reexamined a shape demobilization error of 3D Face Automatic Recognition Apparatus again. Accuracy of a shape demobilization was improved a little. From now on We complement accuracy of a shape demobilization in 3D Face Recognition Apparatus.

• 복식
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• 제64권4호
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• pp.106-117
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• 2014

The purpose of this study is to provide basic information for the development of well-fitting and comfortable brassieres for women in their 30s, based on the classification of breast shapes by utilizing 3D body measurement data of women in the age group. The result of processing the measurements from the 3D body scan data through RapidForm 2006 shows that while the vertical body measurements decrease, the horizontal measurements, which indicates the degree of obesity, increase proportionally with age. Also, the relevant measurements for upper breasts increase proportionally with age, while the measurements for lower part of the breasts decrease as the degree of sagging increases. Four composition factors of the breasts were identified through the factor analysis: Factor 1 is the level of volume in the breasts and the surrounding area; Factor 2 is the position of nipples and the shape of upper part of breasts; Factor 3 is the position and vertical length of the breasts; Factor 4 is the shape of lower part of breasts; and Factor 5 is the shape of inner part of breasts and degree of width between both breasts. The breasts have been categorized into three distinctive shapes: Breast Shape 1, Breast Shape 2 and Breast Shape 3. According to the results of the cluster analysis, the largest percentage (36.68%) of women in their 30s falls into the category of Breast Shape 2 with small volume and flat upper breasts, followed by Breast Shape 1 (32.66%) with large volume in the upper and lower parts of breasts, and large side to side area, and Breast Shape 3 (30.65%) with average volume and width between breasts.

• 농업과학연구
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• 제47권4호
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• pp.753-767
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• 2020

The commercial value of strawberries is affected by various factors such as their shape, size and color. Among them, size determined by weight is one of the main factors determining the quality grade of strawberries. In this study, image technology was developed to predict the weight of strawberries using the shape characteristics of strawberry cultivars. For realtime weight measurements of strawberries in transport, an image measurement system was developed for weight prediction with a charge coupled device (CCD) color camera and a conveyor belt. A strawberry weight prediction algorithm was developed for three cultivars, Maehyang, Sulhyang, and Ssanta, using the number of pixels in the pulp portion that measured the strawberry weight. The discrimination accuracy (R2) of the weight prediction models of the Maeyang, Sulhyang and Santa cultivars was 0.9531, 0.951 and 0.9432, respectively. The discriminative accuracy (R2) and measurement error (RMSE) of the integrated weight prediction model of the three cultivars were 0.958 and 1.454 g, respectively. These results show that the 2D imaging technology considering the shape characteristics of strawberries has the potential to predict the weight of strawberries.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권8호
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• pp.3806-3825
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• 2016

This paper brings out a neoteric frame of reference for visual semantic based 3d video search and retrieval applications. Newfangled 3D retrieval application spotlight on shape analysis like object matching, classification and retrieval not only sticking up entirely with video retrieval. In this ambit, we delve into 3D-CBVR (Content Based Video Retrieval) concept for the first time. For this purpose we intent to hitch on BOVW and Mapreduce in 3D framework. Here, we tried to coalesce shape, color and texture for feature extraction. For this purpose, we have used combination of geometric & topological features for shape and 3D co-occurrence matrix for color and texture. After thriving extraction of local descriptors, TB-PCT (Threshold Based- Predictive Clustering Tree) algorithm is used to generate visual codebook. Further, matching is performed using soft weighting scheme with L₂ distance function. As a final step, retrieved results are ranked according to the Index value and produce results .In order to handle prodigious amount of data and Efficacious retrieval, we have incorporated HDFS in our Intellection. Using 3D video dataset, we fiture the performance of our proposed system which can pan out that the proposed work gives meticulous result and also reduce the time intricacy.

• 대한가정학회지
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• 제43권6호
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• pp.13-25
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• 2005

The purpose of this study was to analyse craniofacial shape by 3D scanner for Korean adult head shape by age group. The heads of 836 adults were measured by 3D scanner, and the 25 obtained measurements were analyzed by statifical methods. The results can be summarized as follows. 1. From the basic statistical data analysis, the vertex-tagion and the length between the pupils were the longest in the subjects in their twenties, and decreased in elderly groups. 2. According to the analysis of the craniofacial proportion, the typical adult Korea head type was short-headed. 3. Statistically noticeable differences were found in the ectocanthion- opistcranion by the measurement of the left and the right sides of face in the age groups of the 20s, 30s, 40s, and 50s. 4. The order of factor analysis was as follows: the horizontal length, the perpendicular length and the width from the highest in the age group of the 20s, 30s, 40s, and 50s.

• 한국멀티미디어학회논문지
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• 제14권6호
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• pp.742-751
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• 2011

본 논문에서는 형상 특징자인 열 커널 인증 (Heat Kernel Signature, HKS)를 기반으로 강인한 3D 모델 해싱을 제안한다. 키와 매개변수에 의존한 형상 특징자 기반 3D 모델 해싱을 제안한다. 제안한 방법에서는 Mesh Laplace 연산자의 고유치와 고유벡터에 의하여 각 꼭지점에 대한 전역 및 국부 타임 HKS 계수를 구한 다음, 이 계수들을 정방형 2D 셀로 군집화한다. 그리고 각 셀에 할당된 HKS 계수 쌍의 거리 가중치 기반으로 정의된 특징계수와 랜덤 계수 키와의 조합에 의하여 중간 해쉬 계수를 생성한 다음, 이진화 과정에 의하여 최종 이진 해쉬를 생성한다. 본 실험에서는 3D 범용 툴을 이용한 다양한 기하하적 공격과 위상학적 공격을 통하여 강인성을 평가하였고, 모델과 키 조합에 대한 해쉬의 유일성을 평가하였다. 또한 인증 범위를 만족히는 공격 세기를 측정함으로써 모델 공간성을 평가하였다. 실험결과로부터 제안한 3D 모델 해싱이 기존 해싱에 비하여 강인성 모델 공간성 및 유일성이 우수함을 확인하였다.