• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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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.

• Korean Journal of Computational Design and Engineering
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• v.18 no.5
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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.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.15 no.4
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• pp.237-242
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• 2022

Acquiring high-quality images in control and measurement systems is one of the important factors. Among image acquisition technologies, SFF (Shape from Focus) is a technology for recovering a 3D shape by acquiring 2D images with different focus levels by moving an object at a predetermined step size along the optical axis. For SFF, when an object is moved at a constant step size, mechanical vibration, referred as jitter noise, occurs in each step along the optical axis. In this paper, a new state estimation filter is designed and applied for reducing the jitter noise. For the application of the proposed method, the jitter noise and focus curves are modeled as Gaussian function. Experimental results demonstrate the effectiveness of proposed method.

• Nuclear Engineering and Technology
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• v.55 no.12
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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.

• Journal of Sasang Constitutional Medicine
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• v.18 no.2
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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.

• Journal of the Korean Society of Costume
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• v.64 no.4
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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.

• Korean Journal of Agricultural Science
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• v.47 no.4
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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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• v.10 no.8
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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.

• Journal of the Korean Home Economics Association
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• v.43 no.6 s.208
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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.

• Journal of Korea Multimedia Society
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• v.14 no.6
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• pp.742-751
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• 2011

This paper presents a robust 3D model hashing dependent on key and parameter by using heat kernel signature (HKS), which is special shape feature descriptor, In the proposed hashing, we calculate HKS coefficients of local and global time scales from eigenvalue and eigenvector of Mesh Laplace operator and cluster pairs of HKS coefficients to 2D square cells and calculate feature coefficients by the distance weights of pairs of HKS coefficients on each cell. Then we generate the binary hash through binarizing the intermediate hash that is the combination of the feature coefficients and the random coefficients. In our experiment, we evaluated the robustness against geometrical and topological attacks and the uniqueness of key and model and also evaluated the model space by estimating the attack intensity that can authenticate 3D model. Experimental results verified that the proposed scheme has more the improved performance than the conventional hashing on the robustness, uniqueness, model space.