• Korean Journal of Computational Design and Engineering
• /
• v.2 no.1
• /
• pp.1-10
• /
• 1997

Finding the optimum route of ship's pipes is complicated and time-consuming process. Experience of designers is the main tool in this process. To reduce design man-hours and human errors a design expert system shell and a geometric modeler is used to automate the design process. In this paper, a framework of the intelligent CAD system for pipe auto-routing is suggested, which consists of general-purpose expert system shell and a geometric modeler. The design expert system and the geometric modeling kernel have been integrated. The CADDS5 of Computervision is used as the overall CAD environment. The Nexpert Object of Neuron Data is used as the expert system shell. The CADDS5 ISSM is used as the interface that creates and modifies geometric models of pipes. Existing algorithms for the routing problem have been analyzed. Most of them are to solve the 2-D circuit routing problems. Ship piping system, specially within the engine room, is a complicated, large scale 3-D routing problem. Methods of expert system have been used to find the route of ship pipes on the main deck.

• Advances in Computational Design
• /
• v.5 no.1
• /
• pp.13-34
• /
• 2020

As small size and complex metal machining components demand increases, cutting processes in microscale become necessary. Ball-end milling is a commonly used finishing process, which nowadays can be applied in the microscale size. Surface quality and dimensional accuracy are two basic parameters that affect small size components in their assembly and functionality. Thus, good quality can be achieved by optimizing the cutting conditions of the procedure. This study presents a 3D simulation model of ball-end milling in microscale developed in a commercial CAD software and its optical and computing results. These carried out results are resumed to surface topomorphy, surface roughness, chip geometry and cutting forces calculations that arising during the cutting process. A great number of simulations were performed in a milling machine centre, applying the discretized kinematics of the procedure and the final results were compared with measurements of Al7075-T651 experiments.

• Korean Journal of Radiology
• /
• v.21 no.10
• /
• pp.1150-1160
• /
• 2020

Objective: To describe the experience of implementing a deep learning-based computer-aided detection (CAD) system for the interpretation of chest X-ray radiographs (CXR) of suspected coronavirus disease (COVID-19) patients and investigate the diagnostic performance of CXR interpretation with CAD assistance. Materials and Methods: In this single-center retrospective study, initial CXR of patients with suspected or confirmed COVID-19 were investigated. A commercialized deep learning-based CAD system that can identify various abnormalities on CXR was implemented for the interpretation of CXR in daily practice. The diagnostic performance of radiologists with CAD assistance were evaluated based on two different reference standards: 1) real-time reverse transcriptase-polymerase chain reaction (rRT-PCR) results for COVID-19 and 2) pulmonary abnormality suggesting pneumonia on chest CT. The turnaround times (TATs) of radiology reports for CXR and rRT-PCR results were also evaluated. Results: Among 332 patients (male:female, 173:159; mean age, 57 years) with available rRT-PCR results, 16 patients (4.8%) were diagnosed with COVID-19. Using CXR, radiologists with CAD assistance identified rRT-PCR positive COVID-19 patients with sensitivity and specificity of 68.8% and 66.7%, respectively. Among 119 patients (male:female, 75:44; mean age, 69 years) with available chest CTs, radiologists assisted by CAD reported pneumonia on CXR with a sensitivity of 81.5% and a specificity of 72.3%. The TATs of CXR reports were significantly shorter than those of rRT-PCR results (median 51 vs. 507 minutes; p < 0.001). Conclusion: Radiologists with CAD assistance could identify patients with rRT-PCR-positive COVID-19 or pneumonia on CXR with a reasonably acceptable performance. In patients suspected with COVID-19, CXR had much faster TATs than rRT-PCRs.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.18 no.1
• /
• pp.43-56
• /
• 1994

The Purpose of this study was to utilize of CAD System in pattern making process for women's apparel. The automation by the use of CAD System provides the higher accuracy and efficiency in pattern making process. AccuMark 300 System was used. for .this study. The results from this study were as follows . 1. New size spec chart and grading pitch chart were developed based on the data analysis and fitting tests for female college students. 2. New jacket block was developed based on the torso length sloper 3. Automatic grading of jacket block have been developed by creation and modification of grading rules of block pattern. 4. Pattern Design Systyem(P/D/S) were enabled to be constructed directly form a block pattern by modifications to existing styled pattern. 5. Original master pattern was generated by P/D/S menu option. 6. Production pattem added seam allowance, notchs was generated by P/D/S menu option. 7 Interative maker making process have enabled to save a wide range of time and space. 8. Measurement of garment by P/D/S measuring tools is to utilize in garment costing, quality control.

• Korean Journal of Adult Nursing
• /
• v.29 no.1
• /
• pp.32-40
• /
• 2017

Purpose: The purpose of this secondary data analysis was to identify factors influencing a relapse among patients with coronary artery disease (CAD). Methods: Of 250 participants enrolled in the original study 75 were selected as there was no relapse for more than one year following the initial treatment and 54 were selected because there was a relapse. Data were analyzed using ${\chi}^2$ test, t-test or F test to determine if there were any significant differences in the study variables relative to the status of relapse. Predictors were calculated by logistic regression. Results: Autonomy supported by healthcare providers was the significant predictor for relapse in patients with CAD. Patients with low autonomy supported by healthcare providers was 3.91 times more likely to relapse than patients with high autonomy supported. Patients with diabetes were at greater risk of recurrence. Conclusion: Secondary prevention of CAD is a major task for patients with CAD. Behavioral strategies for cardiovascular risk reduction are essential and autonomy supported by healthcare providers should be included in their strategies.

• Journal of the Society of Naval Architects of Korea
• /
• v.43 no.1 s.145
• /
• pp.103-118
• /
• 2006

At the initial design stage, the generation process of the production material information of a building block and the simulation process of the block erection, which are required to perform the production planning and scheduling, have been manually performed using 2D drawings, based on the data of parent ships, and subjective intuition from past experience. To make these processes automatic, the accurate generation method of the production material information and the convenient simulation method of the block erection based on the initial hull structural model(3D CAD model), were developed in this study. Here, the initial hull' structural model was generated from the initial hull structural CAD system early developed by us. To evaluate the developed methods. these methods were applied to corresponding processes of a deadweight 300,OOOton VLCC. As a result. it was shown that the production material information of a building block can be accurately generated and the block erection can be conveniently simulated in the initial design stage.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.27 no.12
• /
• pp.1381-1389
• /
• 2003

컴퓨터와 첨단영상매체의 발달로 디자인 분야에서도 컴퓨터를 사용하여 색을 자유롭게 선택할 수 있는 그래픽 소프트웨어가 도입되고 있으나 영상정보의 색채 재현성과 영상입출력 장치의 다양화로 인한 색채 불일치에 대한 문제들이 극복해야할 시급한 과제로 부각되고 있다. 따라서, 색채 영상정보 입출력장치의 색채구현 성능과 인간의 색채인지 원리이론을 바탕으로 색보정 알고리즘이 발전하여 색보정 엔진의 개발이 국제적으로 활발히 진행되고 있는 연구 분야임에도 불구하고 국내에서는 그 연구사례가 상대적으로 극히 미비한 실정이며, 더욱이, CAD 시스템을 이용한 패션/텍스타일 디자인 분야에서는 이에 대한 연구가 거의 이루어지지 않고 있다. 본 연구에서는 염색 직물의 색을 CAD시스템을 이용하여 soft-copy로 재현하고 이것을 다시 hard-copy로 출력하여 물리적 측정치와 주관적 색채 인지도간의 일치도를 비교하고, 물리적, 주관적 색차의 한계치를 제시함으로써, 패션/텍스타일 디자인 CAD시스템 운용에 기초가 되는 자료를 제공하려 하였다. 연구의 절차는 객관적 측정과 주관적 평가 두 단계로 나누어 진행되었다 연구에 사용된 직물은 7가지 색상의 면 염직물로써, CAD시스템을 이용하여 각 직물당 5개의 soft-copy를 재현하고, 이것을 다시 hard-copy로 출력하여 spectrophotometer를 이용해 물리적 측정(ΔE, ΔL, Δc, Δh)을 실시하였다. 또한 주관적 평가에는 20명의 의류학 전공 학생들이 참여하였다. 결과 분석에는 분산분석과 Friedman분석이 사용되었다. 연구 결과 색차 측정에 대한 물리적 측정치와 1차 주관적 평가치 사이의 일치도는 90.5%로 나타났으며, 2차 주관적 평가치와의 rank order는 거의 일치하는 것으로 나타났다. 또한 주관적 평가에서 피험자들은 색차인지에 있어 CIELAB 색채공간의 각각의 색요소 차이보다는 전체 색차에 더 영향을 받는 것으로 나타났다.녹색콩풍뎅이의 유충에 의하여 피해를 받는 것이 확인되었다. 녹색콩풍뎅이 유충의 피해를 받은 금잔디는 황화되거나 시들음 증상이 있었고, 이듬해 봄에는 잔디의 회복이 지연되었다.ic conductivity. The changes of $varepsilon$′ and $varepsilon$" were well estimated with this modified Havriliak-Negami model.05). 상기의 결과를 토대로, 성장과 전어체내 지방산조성에 있어서 뱀장어 치어의 사료내 EPA와 DHA의 첨가효과 미약한 것으로 판단되며, 사료내 LNA (n-3)와 LA(n-6) HUFA을 각각 0.35%, 0.65% 첨가했을 때 WG, SGR, FE, PER이 가장 높았으나, 이전의 실험(Takeuchi, 1980)과 동일한 수준인 n-3와 n-6를 각각 0.5%씩 첨가한 실험구와는 유의적인 차이를 보이지 않았다. 이렇게 볼 때, 뱀장어 치어의 필수지방산은 LNA (n-3), LA (n-6)이고, 그 적정수준은 각각 0.35-0.5%, 0.5-0.65%임을 보여준다.George W, Bush)가 새로운 지도자로 취임하여 얼마 되지 않은 2001년 9월 11일 사상 초유로 본토에서 알 카에다 테러리스트 조직에 의해 공격받게 되었다. 뉴욕의 세계무역센터 빌딩 2개가 완전히 붕괴되고, 펜타곤에 민간 여객기가 충돌하여 많은 사람이 살상 당하고, 전체적으로 세계 80여 개국으로부터의 6천여 명이 살상되었다. 전 세계와 미국은 국제 테러리스트들의 야만적 행위에 대해 경악하고 이제 미국은 그 대외정책의 최우선순위를 국제 테러를 발본색원하는 것에 두게 되었다. 본 논문은 1998년 한국에서 새로이 출범한 김대중 행정부가 북한에 대해 실시한 포용정책이 어떠한 성과를 거두고 어떠한 문제점을 간과하고 있는가에 대해 논의하고, 대북 정책의 새로운 지평을 논의하는 것을 목적으로 하고

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.35 no.6
• /
• pp.1367-1375
• /
• 2015

The purpose of this paper is to suggest 10 mm aggregate specification for thin layer asphalt pavement using steel slag. Aggregate gradations of conventional dense-graded asphalt mixtures were made by fuller's model, whereas 10 mm dense-graded asphalt mixture was obtained tender mix due to close to the maximum density line. The proposed aggregate gradation specification was made to have enough VMA and well-interlocking refer to foreign standards. The correlation between the proposed aggregate gradation and the properties of mixtures were analyzed using Gradation Ratio (GR) and Compacted Aggregate Density (CAD). The CAD index has a high $R^2$ of 0.86-0.99 because the CAD index is able to reflect various aggregate properties. As the results of evaluation by CAD index the proposed aggregate gradation provides more reliable stability and VMA. The percent passing (%) of aggregate size smaller than 0.3 mm was limited 10% or more for improving crack resistance. This limitation increased for 15% of the asphalt mixture's toughness.

• Journal of KIISE:Software and Applications
• /
• v.32 no.1
• /
• pp.34-40
• /
• 2005

Despite the wide range of information and engineering visualization techniques available, studies in investigating the effectiveness of the techniques in visualization has been rare. The typical visualization techniques were CAD, 2D and 3D computer graphics, and virtual environment (VE) that use 3D displays of 3D. space. The objects of this study is to analyze the user preferences and workload changes according to the visualization methods of engineering drawings such as 2D CAD, 2D computer graphics, 3D computer graphics, and augmented reality which is a variation of VEs. The results showed that users preferred 3D visualization techniques to 2D visualization techniques, though there were no workloads differences. Furthermore, the 3D perspective of AR which analogies the real world could facilitate the interpretation of engineering drawings.

• International Journal of CAD/CAM
• /
• v.8 no.1
• /
• pp.21-28
• /
• 2009

In the present work, an attempt has been made to construct branching surface from 2-D contours, which are given at different layers and may have branches. If a layer having more than one contour and corresponds to contour at adjacent layers, then it is termed as branching problem and approximated by adding additional points in between the layers. Firstly, the branching problem is converted to single contour case in which there is no branching at any layer and the final branching surface is obtained by skinning. Contours are constructed from the given input points at different layers by energy-based B-Spline approximation. 3-D curves are constructed after adding additional points into the contour points for all the layers having branching problem by using energy-based B-Spline formulation. Final 3-D surface is obtained by skinning 3-D curves and 2-D contours. There are three types of branching problems: (a) One-to-one, (b) One-to-many and (c) Many-to-many. Oneto-one problem has been done by plethora of researchers based on minimizations of twist and curvature and different tiling techniques. One-to-many problem is the one in which at least one plane must have more than one contour and have correspondence with the contour at adjacent layers. Many-to-many problem is stated as m contours at i-th layer and n contours at (i+1)th layer. This problem can be solved by combining one-to-many branching methodology. Branching problem is very important in CAD, medical imaging and geographical information system(GIS).