• 대한지구과학교육학회지
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• 제9권2호
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• pp.186-198
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• 2016

연구의 목적은 예비 지구과학 교사들이 이해하고 있는 암석 순환의 구성요소와 과정에 대해 밝히는 것이다. 남부 지역에 소재한 사범대학교 2학년에 재학하면서 지구과학 수업을 수강하는 25명의 예비교사들이 연구대상으로 선정되었다. 암석 순환의 구성요소들을 구조적으로 배열하고, 순환 방향을 화살표로 표시하고, 순환 과정에 대해 서술하는 방법을 적용하였다. 예비교사들이 이해하는 암석순환의 구성요소는 마그마, 화성암, 변성암, 퇴적물, 퇴적암의 5가지로, 순환의 과정은 20가지로 표현되었다. 순환의 유형은 선형, 삼각형, 원형, 복합형의 4가지 기준으로 분석되었으며, 일부 예비교사들은 순환의 고리를 완성하지 못하거나 한 방향의 단순한 순환 구조로 시스템적이지 못한 이해를 표출하였다. 암석 순환은 역동성과 복잡성으로 특징되는 지구계 교육의 주제로서 중요한 의미가 있다.

• 한국의류학회지
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• 제15권4호
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• pp.393-403
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• 1991

The purpose of this study were to explain the difference in body dimensions and body shape between the early in the twenties and the late in the twenties and to get information clothing construction. Subject were 483 Korean males, which were extracted from men's physique investigation on June to August in 1989, consisted of 149 aged $19\~24$ and $25\~29$. T-test and factor analysis were applied to 52 measurement items and 58 indices. The Result of the study were as follow; 1. As regards $19\~24$ aged group, they were taller their waistband level was higher than the late in the twenties. Upper arm and thigh were thick in comparison with trunk. As the difference between shoulder and waist in dimension was great, they showed reverse triangular silhouette. As regard $25\~29$ aged group, their body from variation between individual was greater than that of 19~24 aged group and they were obese on mainly waist and abdominal parts. For that reason, waist band level became low and their shoulder and hip looked slim relatively that reason, waist band level became low and their shoulder and hip look slim relatively to bust and waist parts. 2. Between $19\~24$ aged and $25\~29$ aged groups, as each had charicteristic body from, there was the difference in factor structure. 3. The change of men's body from with age in their twenties was obeseness on the whole body but the increasing rate of upper arm and thigh girth was less than that of trunk girth.

• 정보처리학회논문지B
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• 제17B권3호
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• pp.183-188
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• 2010

본 연구에서는 여러 이미지를 이용하여 사실적인 3차원 장면의 모델을 얻는 방법이 구현되었다. 이미지는 파라메터를 모르는 카메라를 이용하여 여러 위치에서 획득한 것을 사용하였다. 먼저 특징점 추출 및 추적 방법을 사용하여 모든 이미지에 대한 대응점들을 구하고 이 점들을 사용하여 사영복원을 구한다. 그 다음 사영 복원된 값에 여러 제약조건을 사용하여 유클리디언 복원을 하면 특징점들의 3차원 좌표값이 계산된다. 이 좌표값을 이용하여 삼각형 메쉬를 구한 후 이 면에 텍스처 맵핑을 하면 사실적인 복원이 완성된다. 전체 시스템은 C++언어로 구현하였으며, 사용자 인터페이스는 Qt 라이브러리로, 텍스처 맵핑과 모델 가시화 부분은 OpenGL 그래픽스 라이브러리로 구현하였다. 구현된 시스템의 효용성을 보이기 위해 모의 데이터와 실제 이미지 데이터를 이용하여 실험한 결과를 포함하였으며 만족할 만한 복원 결과를 얻을 수 있었다.

• Geomechanics and Engineering
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• 제13권6호
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• pp.929-946
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• 2017

Composite foundation treated with compaction piles can eliminate collapsibility and improve the bearing capacity of foundation in loess area. However, the large number of piles in the composite foundation leads to difficulties in the analysis of such type of engineering works. This paper proposes two simplified methods to quantify the stability of composite foundation treated with a large number of compaction piles. The first method is based on the principle of making the area replacement ratios of the simplified model as the same time as the practical engineering situation. Then, discrete piles arranged in a triangular shape can be simplified in the model where the annular piles and compacted soil are arranged alternately. The second method implements equivalent continuous treatment in the pile-soil area and makes the whole treated region equivalent to a type of composite material. Both methods have been verified using treated foundation of an oil storage tank. The results have shown that the differences in the settlement values obtained from the water filled test in the field and those calculated by the two simplified methods are negligible. Using stability analysis, the difference ratios of the static and dynamic safety factors of the composite foundation treated with compaction piles calculated by these two simplified methods are found to be 3.56% and 5.32%, respectively. At the same time, both static and dynamic safety factors are larger than the general safety factor, which should be greater than or equal to 2.0 according to the provisions in civil engineering. This indicates that after being treated with compaction piles, the bearing capacity of the composite foundation is effectively improved and the foundation has enough safety reserve.

• 한국재난정보학회 논문집
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• 제15권1호
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• pp.121-132
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• 2019

연구목적:알바알토의 건축적 사고에서 가장 우선시되는 사람과 자연에 대한 해석 및 지역의 전통적 측면을 고려하여 근대의 사회적 특성과 시대변화가 빛, 형태, 재료 측면에서 건축공간에 어떻게 반영되는지 분석하고자 한다. 연구방법: 근대의 북구건축 및 핀란드건축의 특성을 파악하고 모더니즘의 관점에서 알바알토의 건축 어휘를 종합하여 빛, 형태, 재료를 삼각 구도로 잡고 이들의 상호관계를 문헌자료 및 도면을 통해 분석한다. 연구결과:알바알토의 건축작품은 빛, 형태, 재료, 공간의 다양함을 조합한 것이 중심을 이룬다. 사회적인 지각이 강조되고 휴먼스케일과 건물 환경이 연결된다. 건축의 기능에 따라 새로운 적용방식으로 이들 요소는 재창조된다. 결론: 알바알토의 건축은 전통과 모더니즘 사이에서 자연과 문화, 사회와 개인, 표준화와 다양성, 보편성과 지역성, 지적인 것과 감성적인 것, 과학기술과 인간심리적인 것, 합리성과 직관적인 것 등 서로 이질적이면서 상반된 요소들을 건축공간에 종합적으로 적용시키고 사회적 변화를 수용하여 건축적 언어의 네트워크를 통해 재통합하는 특성을 갖는다.

• 한국콘텐츠학회논문지
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• 제22권9호
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• pp.497-509
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• 2022

선(lines)은 인류 역사에서 가장 오래된 시각적 요소이자 인간의 삶과 밀접하게 연관됐으며, 동굴벽화나 바위에 선으로 그려진 그림 및 기호는 인간의 생존을 위한 대체 이미지로 존재해 왔다. 미술에서 선은 단시간 내에 대상의 핵심을 드러내며, 미술치료에서는 내담자의 심리적 상태를 진단하고 치료적으로 개입할 수 있는 매개체가 된다. 그러나 선 그리기, 즉 선화(line drawing)는 진단뿐 아니라 과정상에서 치료적 중요성을 지님에도 불구하고 그 효용성과 치료적 특성을 고찰한 연구는 활발히 이루어지지 못했다. 따라서 본 연구에서는 미술치료에서 선화와 연관된 국내외 문헌을 이론 삼각검증, 질적 내용분석, 공통부분 찾아내기를 통해 우선 도출한다. 그 결과 선화의 핵심적인 치료적 요소인 운동성을 뇌 구조와 연결하여 살펴본다. 이를 통해 선화의 운동성이 신체, 뇌, 마음에 미치는 치료적 메커니즘을 고찰하고 미술치료 안에서 어떻게 치료적으로 활용 가능한가를 검토 및 제안하는 데 학문적 의의를 둔다.

• Steel and Composite Structures
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• 제46권4호
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• pp.471-483
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• 2023

This paper presents an analytical hyperbolic theory based on the refined shear deformation theory for mechanical stability analysis of the simply supported advanced composites plates (exponentially, sigmoidal and power-law graded) under triangular, trapezoidal and uniform uniaxial and biaxial loading. The developed model ensures the boundary condition of the zero transverse stresses at the top and bottom surfaces without using the correction factor as first order shear deformation theory. The mathematical formulation of displacement contains only four unknowns in which the transverse deflection is divided to shear and bending components. The current study includes the effect of the geometric imperfection of the material. The modeling of the micro-void presence in the structure is based on the both true and apparent density formulas in which the porosity will be dense in the mid-plane and zero in the upper and lower surfaces (free surface) according to a logarithmic function. The analytical solutions of the uniaxial and biaxial critical buckling load are determined by solving the differential equilibrium equations of the system with the help of the Navier's method. The correctness and the effectiveness of the proposed HyRPT is confirmed by comparing the results with those found in the open literature which shows the high performance of this model to predict the stability characteristics of the FG structures employed in various fields. Several parametric analyses are performed to extract the most influenced parameters on the mechanical stability of this type of advanced composites plates.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2022년도 춘계학술대회
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• pp.587-588
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• 2022

본 논문에서는 다수의 모션 캡처 카메라의 2D 패시브마커 영상을 이용한 3차원 공간에서의 리지드 바디(Rigid Body) 추적 방법을 제안한다. 1차로 개별 카메라의 내부 변수를 구하기 위해 체스보드를 이용한 칼리브레이션 과정을 수행하고, 2차 보정 과정에서 3개의 마커가 있는 삼각형 구조물을 모든 카메라가 관찰 가능하도록 움직인 후 프레임별 누적된 데이터를 계산하여 카메라간의 상대적인 위치정보의 보정 및 업데이트를 진행한다. 이 후 각 카메라의 좌표계를 3D월드 좌표계로 변환하는 과정을 통해 3개 마커의 3차원 좌표를 복원하여 각 마커간 거리를 계산하여 실제 거리와의 차이를 비교한 결과 2mm 이내의 오차를 측정하였다.

• Geomechanics and Engineering
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• 제32권4호
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• pp.375-385
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• 2023

There are many joint fissures distributed in the engineering rock mass. In the process of geological history, the underground rock mass undergoes strong geological processes, and undergoes complex geological processes such as fracture breeding, expansion, recementation, and re-expansion. In this paper, the damage-stick-slip process (DSSP), an analysis model used for rock mass failure slip, was established to examine the master control and time-dependent mechanical properties of the new and primary fractures of a multi-fractured rock mass under the action of stress loading. The experimental system for the recemented multi-fractured rock mass was developed to validate the above theory. First, a rock mass failure test was conducted. Then, the failure stress state was kept constant, and the fractured rock mass was grouted and cemented. A secondary loading was applied until the grouted mass reached the intended strength to investigate the bearing capacity of the recemented multi-fractured rock mass, and an acoustic emission (AE) system was used to monitor AE events and the update of damage energy. The results show that the initial fracture angle and direction had a significant effect on the re-failure process of the cement rock mass; Compared with the monitoring results of the acoustic emission (AE) measurements, the master control surface, key blocks and other control factors in the multi-fractured rock mass were obtained; The triangular shaped block in rock mass plays an important role in the stress and displacement change of multi-fracture rock mass and the long fissure and the fractures with close fracture tip are easier to activate, and the position where the longer fractures intersect with the smaller fractures is easier to generate new fractures. The results are of great significance to a multi-block structure, which affects the safety of underground coal mining.

• 대한치과교정학회지
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• 제53권4호
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• pp.254-263
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• 2023

Objective: The evidence on the accuracy of bite registration using intraoral scanners is sparse. This study aimed to develop a new method for evaluating bite registration accuracy using intraoral scanners. Methods: Two different types of models were used; 10 stone models and 10 with acrylic resin teeth. A triangular frame with cylindrical posts at each apex (one anterior and two posteriors) was digitally designed and manufactured using three-dimensional (3D) printing. Such a structure was fitted in the lingual space of each maxillary and mandibular model so that, in occlusion, the posts would contact their opposing counterparts, enforcing a small interocclusal gap between the two arches. This ensured no tooth interference and full contact between opposing posts. Bite registration accuracy was evaluated by measuring the distance between opposing posts, with small values indicating high-accuracy. Three intraoral scanners were used: Medit i500, Primescan, and Trios 4. Viewbox software was used to measure the distance between opposing posts and compute roll and pitch. Results: The average maximum error in interocclusal registration exceeded 50 ㎛. Roll and pitch orientation errors ranged above 0.1 degrees, implying an additional interocclusal error of around 40 ㎛ or more. The models with acrylic teeth exhibited higher errors. Conclusions: A method that avoids the need for reference hardware and the imprecision of locating reference points on tooth surfaces, and offers simplicity in the assessment of bite registration with an intraoral scanner, was developed. These results suggest that intraoral scanners may exhibit clinically significant errors in reproducing the interocclusal relationships.