• 대한치과보철학회지
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• 제52권4호
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• pp.279-286
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• 2014

목적: 임플란트가 식립되는 동적과정을 유한요소해석으로 모사하여, 임플란트 나사형상 차이가 변연골의 식립 응력발생에 미치는 영향을 조사하고자 한다. 재료 및 방법: 코어직경 3.5 mm, 매식부 길이 10 mm인 Straumann 임플란트 몸체 외형에 서로 다른 4종의 나사산이 부여된 가상의 임플란트 모델 4개를 CAD 프로그램을 이용하여 각각 제작하였다. 4종 나사산은 buttress 형, v-자 형, reverse buttress 형, square 형이며, 나사산의 높이와 피치는 0.3 mm와 1.0 mm로 모두 동일하다. 각 임플란트가 3.8 mm pilot hole을 갖는, 1.2 mm 두께 치밀골에 식립되는 과정을 $DEFORM^{TM}$ 3D (ver. 6, SFTC, Columbus, OH, USA) 프로그램을 사용하여 모사/해석하였으며, 식립이 진행되는 과정에 인접골에 생성/누적되는 응력(식립응력)을 비교 분석하였다. 결과: 임플란트 식립 초기, 그 하단부가 pilot hole 내로 진입하며 나사산이 골벽을 압박/변형시키는 단계에서 식립 토오크와 응력이 급격히 발생하였으며 그 이후에 토오크와 응력이 모두 감소하는 변화를 보였다. 식립 응력은 임플란트 나사산 형상에 따라 현저한 차이가 있었으며, v-자형 나사산 경우가 가장 낮았고, square 형의 경우가 가장 높았다. 나사산 차이가 인접골 응력에 미치는 영향은 나사산 첨부 보다는 기저부에 인접한 위치에서 더 현저하였다. 결론: 임플란트 식립응력을 낮추어 골융합에 유리한 환경을 조성하는데는 나사산 첨부가 상대적으로 날카로운 v-자형 나사산이 유리하다.

• 패션비즈니스
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• 제24권1호
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• pp.102-116
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• 2020

After its introduction in Korea, nail art is becoming active, especially among women in their 20s and 30s who are interested in fashion and beauty. Although self-nail tips are available online in various designs for each brand that is currently on the market, these designs and sizes of self-nail tips on the market are different for each age group. Since the design or size is not suggested for the different situations, there are difficulties in purchasing products that match the shape and size of nails of consumers. In this study, frequency analysis was performed using 'SPSS statistics 21.0 for windows program' to analyze data obtained by direct measurement method and 3D scanner measurement method for Korean women in their 20s. For comparative analysis between direct and 3D scanner measurements, a corresponding sample, 'T-test', was performed. As a result, we proposed the standardization of nail tip size after comparative analysis between direct measurement and 3D scanner measurement. Previous studies have been proceeding with direct measurement method. However, this study introduced a 3D scanner measurement method in the nail field and attempted the standardization of nail size by age group of Korean women. Importantly, this sutdy suggests standardization of nail tip size among missing body sizes.

• 한국생활과학회지
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• 제24권4호
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• pp.555-569
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• 2015

During a design process of a protective equipment for sports activities, minimizing movement restrictions is important for enhancing its functions particularly for protection. This study presents a three-dimensional(3D) modeling methodology for designing baseball catcher's leg guards that will allow maximum possible performance, while providing necessary protection. 3D scanning is performed on three positions frequently used by a catcher during the course of a game by putting markings on the subject's legs at 3cm intervals : a standing, a half squat with knees bent to 90 degrees and 120 degrees of knee flexion. Using data obtained from the 3D scan, we analyzed the changes in skin length, radii of curvatures, and cross-sectional shapes, depending on the degree of knee flexion. The results of the analysis were used to decide an on the ideal segmentation of the leg guards by modeling posture. Knee flexions to 90 degrees and to $120^{\circ}$ induced lengthwise extensions than a standing. In particular, the vertical length from the center of the leg increases to a substantially higher degree when compared to those increased from the inner and the outer side of the leg. The degree of extension is varied by positions. Therefore, the leg guards are segmented at points where the rate of increase changed. It resulted in a three-part segmentation of the leg guards at the thigh, the knee, and the shin. Since the 120 degree knee-flexion posture can accommodate other positions as well, the related 3D data are used for modeling Leg Guard (A) with the loft method. At the same time, Leg Guard (B) was modeled with two-part segmentation without separating the knee and the shin as in existing products. A biomechanical analysis of the new design is performed by simulating a 3D dynamic analysis. The analysis revealed that the three-part type (A) leg guards required less energy from the human body than the two-part type (B).

• Maxillofacial Plastic and Reconstructive Surgery
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• 제33권4호
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• pp.337-345
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• 2011

Purpose: The purpose of this study was to define the relation of the degree of menton deviation and 3-D CT (computerized tomography) measurements of the glenoid fossa and the mandible, which are considered to have an influence on menton deviation. Methods: The CT images were obtained in 60 adults and these were transmitted to a computer and reconstructed using computer software. According to the degree of the menton deviation, which was measured on the posteroanterior cephalogram, the subjects were divided into the menton deviated group (30 adults) and the symmetry group (30 adults). A total of 11 measurements that might have an effect on menton deviation were determined and these were measured in the right and left sides using the function of 3-D measurement in the computer program. The 11 measurements consist of 6 measurements in the glenoid fossa (vertical position of the glenoid fossa and articular eminence, the sagittal position of the glenoid fossa and articular eminence, the depth of the glenoid fossa, and the anterior angle of the glenoid fossa), and 5 measurements in the mandible (ramus length, frontal ramal inclination, lateral ramal inclination, body length, body height). Results: The comparison of the differences between the menton deviated and symmetry groups and correlation analysis on the degree of menton deviation were carried out. The results of comparison of the right and the left difference between the menton deviated and symmetry groups showed that the vertical position and depth of the glenoid fossa were significantly increased in the menton deviated group. Conclusion: The results of the present study show that consideration of the shape and position of the glenoid fossa is necessary for making the diagnosis and administering proper treatment in facial asymmetry patients and especially growing patients.

• 한국기계가공학회지
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• 제19권5호
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• pp.45-52
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• 2020

Recently, design for additive manufacturing (DfAM) technology has become a prominent design methodology for exploiting 3D printing, which leads the Fourth Industrial Revolution. When manufactured by the 3D printing method, it is possible to produce several shapes compared to the conventional casting or cutting process. DfAM-as a newly-proposed design methodology-can be used to specially design products with various shapes to apply functional requirements. Topology optimization verifies load paths to determine the draft design, and a shape-optimized design with objective functions for weight reduction enables efficient lightweight product design. In this study, by using these two DfAM technologies, a lightweight and optimal design is constructed for a node part of a vehicle body with a space frame designed for a lightweight vehicle. DfAM methodologies for concept design and detailed design, and the associated results, are presented. Finally, the product was additively manufactured, a fatigue performance test was performed, and the design reliability was verified.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.378-383
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• 2007

As the Minimally Invasive Surgery (MIS) is developed, an interventional procedure becomes the major of the spine surgery in the world. Despite of the use of the expensive medical equipments, the success chance of the nucleoplasty is about 30%. The reason is that the shape of the cannular needle is similar to that of the conventional injector and looks like the straight. Because the tip of these straight needles is not able to reach in the vicinity of the disc bulging or the protrusion, which are the cause of the low back pain and because the far indirect plasma discharge results in the decompression, the nucleoplasty has the limit. Many incurable diseases has not been solved due to the unexistence of the advanced technique for the MIS human body cannula device. If 3-D direction controllable cannular catheter (whose direction is accurately controlled after inserting into the bodies to cure the lesion) is developed, it is expected that new devised cannular catheter can cure many incurable diseases simultaneously. Therefore, the aims of this research are to develop the new devised cannular catheter of SMA direction controller for the medical situation, which has been produced through many previous trial-error procedures, and to produce the commercial medical device.

• 한국자동차공학회논문집
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• 제19권5호
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• pp.113-117
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• 2011

The frame for automotive assembly can be deformed and remained on the residual stress due to high temperature thermal attacks when in welding. The frame deformation can be made to problems when in assembly with body and the residual stress can affect the negative effect on durability performance of the automobile. In order to analyze the frame deformation, the simplified test frame which had the similar shape (form) of the real automotive frame was fabricated. The contactless optical 3D scanner was used for the shape difference measurement of the frame between before and after the welding. The FE-model of the test frame was composed and the heat transfer and thermal stress simulation were performed. The simulated results were compared with the measured results for the reference of the frame design. The deformation shape of the frame by simulation was in good agreement with that by the experimental measurement.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1988년도 한국자동제어학술회의논문집(국제학술편); 한국전력공사연수원, 서울; 21-22 Oct. 1988
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• pp.826-831
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• 1988

This paper presents an approach to segment an image into areas of surfaces, and to compute the surface properties from a gray-scale image in order to describe the surfaces for reconstruction of the 3-D shape of the objects. In general, an rigid body has several surfaces and many edges. But if it is not polyhedoron, it is necessary not only to describe the relation between surfaces, i.e. its line drawings but also to represent the surfaces' equations itself. In order to compute the surfaces' equation we use a probability of edge distribution. At first it is extracted edges from a gray-level image as much as possible. These are not only the points that maximize the change of an image intensuty but candidates which can be seemed to be edges. Next, other character of a surface (color, coordinates and image intensity) are extracted. In our study, we call the all feature of a surface as "texture", for example color, intensity level, orientation of an edge, shape of a surface and so on. These features of a surface on a pixel of an image plane are mapped to a point of the feature space, and segmented to each groups by cluster analysis on this space. These groups are considered to represent object surface in an image plane. Finally, the states of object surface in 3-D space are computed from distributional probability of local and overall statistical features of a surface, and from shape of a surface.a surface.

• 한국의류산업학회지
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• 제21권4호
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• pp.480-487
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• 2019

This study used 3D technology to develop a multi-functional sports brassiere with increased comfort and fit that can be worn as a base layer during exercise or as underwear. A 75A size industrial lingerie figure was used to develop a standard pattern. 3D tools for scanning and pattern making, such as Vivid 910, Geomagic Design X, 2C-AN and Yuka CAD were used. The sports brassiere was designed as a tank top style with dual structure and linings attached to a pad utilized with a sport brassiere mold cup. 3D outer and lining's pattern was differently developed in consideration of the body's curvature with pad's shape and structure. Shoulder and neck part reduction rates were adjusted to increase the neck areas fit that considered the nude pattern's structure due to uncomfortableness felt by wearers who were uncomfortable with the neck areas fit on existing brand products. The reduction rate was also set differently on each part. For example, the reduction rate on outer side panel was set strongly to increase the breast's volume. Two products, developed by a 3D sports brassiere and previously released product, were worn on 8 subjects in their 20's to evaluate fit, comfort, and purchase preferences. The evaluation proved that newly developed 3D products were superior to comparative products. The results of the clothing pressure measurement indicate that the newly developed sports brassiere's front part had less pressure on upper bust and shoulder areas compared to comparative products as well as showed less pressure on the back side, which shows improved wearing comfort compared to comparative products.

• 한국의류학회지
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• 제30권11호
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• pp.1598-1607
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• 2006

The purpose of this study was to analyze the proportion of gathered skirts using a three-dimensional measurement system. And in this experiment, we have attempted to accumulate three-dimensional data of wearing model and find out adequate methods for analyzing shape of clothes. The experimental design consists of two factorial designs. We established three different kinds of fabrics, ratio of gathers. The measurement tool for three-dimensional model was whole body 3D scanner(Exima-WBS2H). Analysis program used in experiment is RapidForm 2004 PP1 and Pattern Design 2000. Data analysis utilizes SPSS WIN 10.0 Package. As the results show, there were different effect of gather and proportion of shapes among the measurements of width, thickness and areas made by different lines of vision in cross-sectional silhouette. And there were difference shapes of section area at each part of gathered skirts between vertical-outline silhouette and vortical-plane silhouette made by gathering conditions. And also the cross-sectional silhouettes and vertical silhouettes were related to shape of clothes.