• 전자공학회논문지SC
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• 제48권6호
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• pp.15-23
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• 2011

스테레오 비젼 방식의 단점을 보완하기 위해 단일 카메라를 이용한 3차원 정밀 거리 측정 및 물체 인식방법을 제안하였다. 단일 카메라, 레이저 광 그리고 회전 평면경을 사용하여 정밀한 3 차원 거리 정보를 얻을 수 있다. 거리정보로 표현된 물체 영역에 간단한 문턱치 처리를 사용하면, 물체의 윤곽을 얻을 수 있으며, 그 윤곽에 대한 시그니처를 데이터베이스와 비교 함으로써, 물체와 그 자세까지 인식할 수 있다. 정밀 거리측정에 의한 물체 인식률 향상을 보이기 위해 시뮬레이션 결과를 제시하였다.

• International Journal of CAD/CAM
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• 제6권1호
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• pp.105-115
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• 2006

Thickness is a commonly used parameter in product design and manufacture. Its intuitive definition as the smallest dimension of a cross-section or the minimum distance between two opposite surfaces is ambiguous for intricate solids, and there is very little reported work in automatic computation of thickness. We present three generic definitions of thickness: interior thickness of points inside an object, exterior thickness for points on the object surface, and radiographic thickness along a view direction. Methods for computing and displaying the respective thickness values are also presented. The internal thickness distribution is obtained by peeling or successive skin removal, eventually revealing the object skeleton (similar to medial axis transformation). Another method involves radiographic scanning along a viewing direction, with minimum, maximum and total thickness options, displayed on the surface of the object. The algorithms have been implemented using an efficient voxel based representation that can handle up to one billion voxels (1000 per axis), coupled with a near-real time display scheme that uses a look-up table based on voxel neighborhood configurations. Three different types of intricate objects: industrial (press cylinder casting), sculpture (Ganesha idol), and medical (pelvic bone) were used for successfully testing the algorithms. The results are found to be useful for early evaluation of manufacturability and other lifecycle considerations.

• 동력기계공학회지
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• 제19권4호
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• pp.11-16
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• 2015

Welding is very popular method for joining two or more metals. In this paper, the three-way factorial design was adopted for obtaining the optimum friction stir welding conditions of Al 5052 alloy. Tools of shoulder diameter of 9, 12, 15 mm and pin length of 1.5 mm were used. Also the material's dimension for welding was $100{\times}100{\times}2mm$, and the tensile specimens were worked by water-jet technique. Welding variables were shoulder diameter, rotating speed of tool and welding speed. As far as this work is concerned, optimum condition for friction stir joint of Al 5052 alloy was predicted as the shoulder diameter of 15 mm, welding speed of 500mm/min and rotating speed of 1000 rpm. In addition, the presumed range of tensile strength under the optimal conditions is estimated to be $208.3{\pm}5.7$ MPa with 99% reliability.

• KCI Concrete Journal
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• 제12권2호
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• pp.73-84
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• 2000

A new form of construction utilizing structural steel as the boundary elements in ductile flexural concrete walls is proposed to solve the bar congestion problems in such a heavily reinforced region, while maintaining the ductility and energy absorption capacity comparable to their traditional form. Two wall specimens containing rectangular hollow structural sections (HSS) and channels at their ends respectively, and one companion standard reinforced concrete wall specimen with concentrated end reinforcement were constructed and tested under reversed cyclic loading to evaluate the construction process as well as the structural performance. Initially, all three specimens were chosen and detailed with some caution to have approximately the same flexural capacity without change of the original shape and dimension of a rectangular cross section correction. Analysis and comparison of test results indicated that the reversed cyclic responses of three walls showed similar hysteretic properties, but in those with steel boundaries, local buckling of the corresponding steel webs and flanges following significant yielding was a dominant factor to determine the hysteretic response. The monotonic and cyclic responses predicted based on a sectional approach was also presented and found to be in good agreement with measured results. Design recommendations considering local instability of the structural steel elements and the interaction between steel chords and a concrete web member in such a composite wall are presented.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.1885-1890
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• 2008

3-D heterogeneous nucleation was simulated by classical molecular dynamics (MD), where the Lennard-Jones (LJ) gas and solid cluster-seed molecules have argon and aluminum properties, respectively. There are three shapes of cluster-seeds, cube, rod, and sphere, and three classes of masses and the simulation took place under nine supersaturation ratios, making a total of 81 calculations. Results show that the dimension of the cluster-seed highly affects the rates of cluster development. In order to analyze heterogeneous nucleation above and below the critical supersaturation ratio, growth rate and liquefaction rate were separately defined to supplement the investigation. Design of experiments (DOE) was used for analysis which displayed that the shape and mass of the cluster-seed are prominent for the growth rate, while the supersaturation ratio is most significant followed by the mass for liquefaction rate. The significance of the supersaturation ratio for overall liquefaction suggests that thermal diffusion is more dominant than mass interactions for this system.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2005년도 추계 종합학술대회 논문집
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• pp.548-551
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• 2005

본 연구에서는 3푹 가속도센서를 소형 센서모듈로 구성하고 이를 사람의 신체 부위에 부착하여 센서의 3차원적 방향에 구애되지 않고 동작에 의한 중력방향의 가속도를 계산할 수 있는 장치와 알고리즘을 개발하였다. 센서모듈을 이용하여 컴퓨터 시스템에 의해 사람의 보행 및 동작을 측정하기 위해서는 정량적인 처리가 가능하도록 데이터를 가공하여야 한다. 센서 모듈로부터 데이터의 획득, 가능한 범위의 직교 좌표계로 변환, 중력방향의 단일 스칼라 값 변환의 과정으로 센서 출력 데이터를 정규화 하였다.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.II
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• pp.139-145
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• 2000

The mechanism of the inner resistance in a rubber crawler system has been investigated to reduce the power requirement (Kitano et al. 1994). The rolling resistance of the track roller, which is one of the major inner resistances, was measured for seven different vertical loads. The rolling resistance changed periodically and could be classified into three types. In case of the vertical load less than 500N, the rolling resistance was almost constant. For the vertical load greater than 500N, the maximum value of the rolling resistance increased. Further more in case of the vertical load greater than 1200N, negative resistance appeared. Analytical simulation of the travel resistance based on experimental results and static equilibrium equations derived from three-dimension mechanical model for the rubber crawler system. It was found that the simulation method was carried out to evaluate the travel resistance occurred by the rolling resistance of the track roller. The rolling resistance for each track roller arrangement and effects of the lug phase in the right and left rubber crawler could be estimated quantitatively.

• Journal of the Korean Wood Science and Technology
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• 제34권1호
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• pp.7-14
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• 2006

국산 소나무 간벌재를 이용한 수심 정각새(단면치수 $150{\times}150mm$)의 안전하고 신속한 건조를 위하여 열풍건조와 마이크로파건조중 수심 정각새의 함수율 분포와 그 변이를 3차원적으로 탐색하였다. 실험결과 마이크로파건조를 통하여 72시간 이내에 함수율 10% 미만까지 건조가 가능하였고 표면할열 발생도 최소화할 수 있었다. 건조 중 함수율 분포는 마이크로파건조의 경우 초기함수율 분포에 영향을 크게 받았다. 그러나 열기건조의 경우 초기함수율 분포가 건조초기에만 영향을 미치는 것으로 나타났다.

• 패션비즈니스
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• 제20권5호
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• pp.30-44
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• 2016

In this study, we used the Q methodology, which is considered an effective way to identify and assess the characterization of the human subjective consciousness, and we intended to carry out a scientific approach to classify cosmetics consumers in a department store. The purpose of this study is to identify the dimension of recognition and the characterization of Korean women who use a department store, as well as to classify cosmetics consumers in a department store. The analyzed data was divided into the top 10 questions and 10 sub-items, and it was then classified into six consumer types, depending on typicality of three factors. The three factors were 'effectiveness', 'goal' and 'congestion of shopping'. We named and analyzed the features of each type through in-depth Q workshops in which 22 professionals participated. This study is meaningful as it used the Q-methodology instead of statistics which had been used before to classify the consumers, so that the 'subjective' estimation was analyzed into 'objective' types. The results of this study are expected to be useful for creating a marketing strategy for the cosmetics industry.

• 한국의류학회지
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• 제21권8호
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• pp.1365-1375
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• 1997

Jacket is the basic formal dress for working women, and one of the most frequently worn by them. It has, however, some problems caused by movement, depending on how well it fits. To improve fitness of jacket, this study compared and evaluated the state of fitness objectively by employing a numerical system in relation with clothing and body. We made three experimental jackets based on the previous jacket patterns and used Moire Photo-graphy to measure the amounts of space between clothes and body from the overlap cross section map. The results obtained from this study were summarized as follows; 1. According to the measurement result of the pattern by using the One-dimension measurement, the amount of ease in girth item for pattern B was larger than the other two patterns. The amounts of space of each part showed the difference of the positions of princess lines, and the different sizes of the darts. 2. From the result of Moire Photography, the wearing shapes of the experimental jackets were influenced by the characteristics of somatotype. In addition, we could analyze the differences of the patterns with Moire Photography. 3. The amounts of space for waist part was larger than those for other parts. Pattern B scored the largest amount of space for all parts compared with pattern A and C. 4. For only waist part, there existed a significant difference in the average amount of space for the three patterns.