• 제목/요약/키워드: Normal Design Point

검색결과 167건 처리시간 0.037초

등기하 해석법을 이용한 형상 최적 설계 (Shape Design Optimization using Isogeometric Analysis Method)

  • 하승현;조선호
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2008년도 정기 학술대회
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    • pp.216-221
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    • 2008
  • Shape design optimization for linear elasticity problem is performed using isogeometric analysis method. In many design optimization problems for real engineering models, initial raw data usually comes from CAD modeler. Then designer should convert this CAD data into finite element mesh data because conventional design optimization tools are generally based on finite element analysis. During this conversion there is some numerical error due to a geometry approximation, which causes accuracy problems in not only response analysis but also design sensitivity analysis. As a remedy of this phenomenon, the isogeometric analysis method is one of the promising approaches of shape design optimization. The main idea of isogeometric analysis is that the basis functions used in analysis is exactly same as ones which represent the geometry, and this geometrically exact model can be used shape sensitivity analysis and design optimization as well. In shape design sensitivity point of view, precise shape sensitivity is very essential for gradient-based optimization. In conventional finite element based optimization, higher order information such as normal vector and curvature term is inaccurate or even missing due to the use of linear interpolation functions. On the other hands, B-spline basis functions have sufficient continuity and their derivatives are smooth enough. Therefore normal vector and curvature terms can be exactly evaluated, which eventually yields precise optimal shapes. In this article, isogeometric analysis method is utilized for the shape design optimization. By virtue of B-spline basis function, an exact geometry can be handled without finite element meshes. Moreover, initial CAD data are used throughout the optimization process, including response analysis, shape sensitivity analysis, design parameterization and shape optimization, without subsequent communication with CAD description.

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인쇄회로기판 검사용 프로브시스템의 광학센서 (An optical sensor of a probing system for inspection of PCBs)

  • 심재홍;조형석;김성권
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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    • pp.1742-1745
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    • 1997
  • We have developed a highly responsible probing system for inspection of electrical properties of assemble PCB$_{s}$ (printed circuit boards). However, as the duration of the impact occurring between a probe and a solder joint on PCB is very short, it is very difficult to control the harmful peak impact force and the slip motion of the probe to sufficient level only by its vorce feedback control with high gains. To overcome these disadvantages of the prototype, it needs ot obtain some information of the solder joint in advance before the contact. In addition, to guarantee the reliability of the probing task, the probing system is required to measure several points around the probale target point at high speed. There fore, to meet such requirements, we propose a new noncontaet sensor capable of detecting simultaneously position and normal vectors of the multiple points around the probable target point in real time. By using this information, we can prepare a control strategy for stable contact motion on impact. In this paper, we described measuring priniciple, design, and development of the sensor. The effectiveness of the proposed sensor is verified through a series of experiments.s.

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A REVIEW OF INHERENT SAFETY CHARACTERISTICS OF METAL ALLOY SODIUM-COOLED FAST REACTOR FUEL AGAINST POSTULATED ACCIDENTS

  • SOFU, TANJU
    • Nuclear Engineering and Technology
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    • 제47권3호
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    • pp.227-239
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    • 2015
  • The thermal, mechanical, and neutronic performance of the metal alloy fast reactor fuel design complements the safety advantages of the liquid metal cooling and the pool-type primary system. Together, these features provide large safety margins in both normal operating modes and for a wide range of postulated accidents. In particular, they maximize the measures of safety associated with inherent reactor response to unprotected, doublefault accidents, and to minimize risk to the public and plant investment. High thermal conductivity and high gap conductance play the most significant role in safety advantages of the metallic fuel, resulting in a flatter radial temperature profile within the pin and much lower normal operation and transient temperatures in comparison to oxide fuel. Despite the big difference in melting point, both oxide and metal fuels have a relatively similar margin to melting during postulated accidents. When the metal fuel cladding fails, it typically occurs below the coolant boiling point and the damaged fuel pins remain coolable. Metal fuel is compatible with sodium coolant, eliminating the potential of energetic fuel-coolant reactions and flow blockages. All these, and the low retained heat leading to a longer grace period for operator action, are significant contributing factors to the inherently benign response of metallic fuel to postulated accidents. This paper summarizes the past analytical and experimental results obtained in past sodium-cooled fast reactor safety programs in the United States, and presents an overview of fuel safety performance as observed in laboratory and in-pile tests.

슬랙스 패턴의 허리뒤점 설계에 따른 외관 및 동작적합성 평가 (Evaluation of Appearance and Optimal for Motion According to the Back Waist Point of Slacks Pattern)

  • 권숙희;홍지운
    • 한국의류학회지
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    • 제37권6호
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    • pp.750-763
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    • 2013
  • This research suggests pattern design methods for motion through an evaluation of the appearance and motion of three existing kinds of original patterns (K type, N type, and L type) and modified patterns designed by the researcher. The results of the study are as follows. First, the evaluation of appearances showed that the modified patterns of a standing posture received a higher evaluation compared to the original patterns only in N type and in a sitting posture. In addition, the degree of lowering or a natural feel by the pulling of the slacks waist belt in a sitting posture received a higher evaluation than the original patterns. Second, the evaluation of motions showed that modified patterns received a higher evaluation than the original patterns in almost all items. Per each pattern, it showed meaningful differences in questions asking about the degree of comfort as the whole in N type in crouching motions. The L type showed low scores as a whole (both in original patterns and modified patterns) and the K type showed meaningful differences in questions asking about the degree of comfort of the crista iliaca and groin region in the motion of walking at a normal walking pace, ascending stairs and bending the waist 90 degree to the front. Third, the measuring distance the between back waist point of the body and the back waist point of original patterns and modified patterns during motions showed that the modified patterns of all three patterns (N type, L type, and K type) showed less lowering compared to the original forms in the whole pattern as well as individual patterns. The design method of back waist point developed in this research can be regarded as a design method appropriate for motions.

경계면스캔에서의 선택가능한 관측점 시험구조의 개발 (Development of selectable observation point test architecture in the Boundry Scan)

  • 이창희;장영식
    • 한국컴퓨터정보학회논문지
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    • 제13권4호
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    • pp.87-95
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    • 2008
  • 경계면 스캔 구조는 시험대상회로의 출력 값들을 캡쳐하여 스캔경로를 이용하여 TDO로 직렬출력하여 출력 값을 관찰할 수 있는 시험구조이며, Sample/preload명령어를 이용하여 시험대상회로의 특정한 한 순간의 출력만을 캡쳐하여 직렬출력하여 분석할 수 있다. 본 논문에서는 4비트 비동기 카운터회로를 시험대상회로로 선정하고, 정상동작중인 카운터의 특정 출력을 지정하여 특정한 순간의 정적인 출력이 아닌, 연속적인 동적인 출력 값들을 다른 출력결과의 영향 없이 지속적으로 TDO로 출력하여 관찰할 수 있는 선택 가능한 관측점을 가진 시험구조와 시험절차를 개발하였다. 본 논문에서 제안하는 선택 가능한 관측점을 가진 시험구조는 표준에서 정한 시험동작을 정상적으로 수행하며, 관측점의 설정을 위한 명령어가 추가되었다. 4비트 카운터회로에 제안된 선택 가능한 관측점 시험구조를 적용 설계하고, 관측점 설정 명령어를 사용한 시험절차를 Altera의 Max 10.0을 이용한 시뮬레이션을 통해 동작의 정확성을 확인하였다.

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운동 트레이닝 시스템 구축 방안에 관한 연구 (A Study on the Establishment of Exercise Training System)

  • 오은열
    • 디지털융복합연구
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    • 제19권8호
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    • pp.195-203
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    • 2021
  • 본 연구는 사람의 사용자 전신을 촬영한 이미지를 분석하여, 사용자별 움직임에 대한 정상 가동 범위를 영상으로 디스플레이(display)하는 운동 트레이닝 시스템 구축에 관한 것이다. 본 연구는 입점(立點, standing point)을 기준으로 사용자 전신의 정면과 측면을 촬영하는 카메라부(C), 그리고 카메라부의 촬영 이미지를 분석하여 인체의 관절 위치에 노드(node)를 설정하고, 입점을 원점으로 하는 공간좌표계에 노드를 배치하여 그 사용자의 노드 좌표값을 도출하는 이미지 분석부(I·A)와 이미 설정된 표준 노드 좌표값에 매칭된 운동 동작별 정상 노드 가동범위를 사용자 노드 좌표값에 맞추어 보정하여, 상기에서 언급한 사용자 노드 정상 가동 상태를 정면 영상과 측면 영상으로 생성하여 디스플레이하는 재생부(R·P)를 포함하고 있는 시스템으로 구성된다. 따라서 연구의 방법으로는 주요선행연구와 자료조사를 통해 선행 연구와의 차별성을 기할 수 있는 방법을 제시했으며, 이에 따른 운동 트레이닝 시스템을 구축하고자 하는데 연구의 목적을 둔 것이다.

포스트 코로나 시대에 드라이브 스루 카페를 활용한 도시공원 디자인 제안 (A Proposal of Urban Park Design Using DT Cafe in Post-COVID Era)

  • 길수연;신해민;최주현;김유선
    • 한국화예디자인학연구
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    • 제45호
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    • pp.31-46
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    • 2021
  • 본 연구에서는 포스트코로나 시대의 방역을 위한 사회적 거리두기는 유지하되, 그 이전의 삶을 향유할 수 있는 공간을 재탄생 시켜야 한다는 목적을 가지고 드라이브 스루를 활용한 도시공간 디자인 뉴노멀 계획안을 제시하고자 하였다. 유동인구가 높고 드라이브 스루가 가능한 공간이 있는 곳으로 올림픽공원을 대상으로 카페와 오륜기를 상징하는 5공간의 공원을 디자인한 결과는 다음과 같았다. 올림픽의 오륜기의 색인 파랑, 노랑, 검정, 초록, 빨강을 이용해 카페의 이름인 CUPPY(Cup+Coffee)에 하나씩 입혀 카페 로고를 표현했다. 올림픽의 5대륙(Europe, Asia, Africa, Oceania, America)을 나누어 5개의 공간으로 공원 안이 구성되어 있으며, 드라이빙 루트도 5개의 공간에 맞춰 오륜기 모양으로 구성하였다. 포스트코로나 시대를 살아가기 위한 여러 분야에서의 변화와 적응이 필요하게 되었다. 그 시대마다의 뉴노멀은 달랐고 달라야만 했던 것 같이 코로나 사태 이후의 도시공원 디자인의 뉴노멀을 제시할 수 있는 연구로 도시공원 디자인에 좋은 예시가 될 것으로 기대하며 더 다양한 환경에 적용한 계속적인 제안과 연구가 필요할 것으로 판단된다.

The Design of Photobiological Active Molecular Model For Photodynamic Therapy

  • Choi, Chang-Shik
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2019년도 춘계학술대회
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    • pp.521-524
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    • 2019
  • The design of photobiological active photosensitizing molecular model for photodynamic therapy has been attracted as a research for the development of cancer treatment, and has been interested in the effective method for cancer treatment and the photosensitizer having more stable wavelength. Furthermore, the development of photosensitizer has been already carried out from the first generation molecule to the third one, and the research of smart photosensitizer as the fourth generation has been requested. As a fact, the selective killing of the only cancer cell is very difficult problem, and the present photodynamic therapy has the problem of killing of the normal cell. So, I have designed the new modelling of photosensitizer having the smart recognizing unit and the magnetic nanoparticle as well as having the several effective recognizing unit. In particular, the new model design of the photosensitizer having lanthanide metal has suggested for the development of photodynamic therapy. The model design of these new photosensitizing molecules will be introduced in the poster section for the new turning point of the development of photosensitizer.

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소형비행기 조종실 평가에 대한 인증방법 연구 (Certification on cockpit evaluation for small airplane)

  • 김필수;정봉구
    • 항공우주시스템공학회지
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    • 제6권2호
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    • pp.1-6
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    • 2012
  • On this study, as a Human Factor(HF)'s point of view, typical PVI(Pilot Vehicle Interface) evaluation for small airplane cockpit design, PVI evaluation items and procedures to show compliance to KAS Part 23 "Airworthiness Standards : Normal, Utility, Acrobatic, And Commuter Category Airplanes" are introduced and reviewed. This study is based on the experience of Korean small civil airplane development and certification program.

계절에 따른 생리와 심리의 변화가 의복색 선호에 미치는 영향 (Effect on clothing color preference of seasonal variations in physiology and psychology)

  • 김숙희;이원자
    • 한국의상디자인학회지
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    • 제7권3호
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    • pp.75-81
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    • 2005
  • The experiment aimed at knowing the effect of physiology and psychology according to season on color preference. Two tests, one of the spring and the other of the autumn was conducted. Seventy subjects with normal color vision served as subjects. The subjects entered a bioclimatic chamber controlled at a temperature of $25\pm1^{\circ}C$, a relative humidity of $50\pm5\%$ and a light of 1000 1x. The subjects wearing white shirts and trousers sat quietly on a sofa for one our. Sensation from warm to cool colors might be possibly different individually Therefore, a subject asked to array 41 randomly placed cloth colors from very warm to very cool colors during rest quietly for one our. All subjects arrayed these cloth colors in the order from red through yellow and green to blue, which had the reproducibility. After rest, they were instructed to choose a single one out of 41 cloth colors, preferred by themselves, every 10min during one our 0-ring test were measured to red, yellow, white, blue, black, favorite color, and dislike color. Most subjects preferred warmer color in April than in December. Tympanic temperature was significantly lower in December than in April. Finger presser was significantly higher in like color than in dislike color but it was no significant differences between spring and autumn. The preferring the warm color in April toward summer when basal metabolic rate is decreased than in December toward winter when it is increased can explain that physiology reaction by load error between actual core temperature and set-point induces psychological reaction to pursue visual alliesthesia. Our present experiment revealed that the preferred color could be determined by the relationship between the internal temperature and its set point according to season. It should be emphasized that the alliesthesia was observed also in the realm of visual system.

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