• 제목/요약/키워드: non-planar

검색결과 263건 처리시간 0.026초

사각형 외팔보에서의 일대일 공진 (One to one Resonance on the Rectangular Cantilever Beam)

  • 김명구;박철희;조종두;이흥식
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2005년도 춘계학술대회논문집
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    • pp.424-429
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    • 2005
  • In this paper, the response characteristics of one to one resonance on the rectangular cantilever beam in which basic harmonic excitations are applied by nonlinear coupled differential integral equations are studied. This equations have 3-dimensional non-linearity of nonlinear inertia and nonlinear curvature. Galerkin and multi scale methods are used for theoretical approach to one to one internal resonance. Nonlinear response characteristics of 1st, 2nd, 3rd modes are measured from the experiment for basic harmonic excitation. From the experimental result, geometrical terms of nonlinearity display light spring effect and these terms play an important role in the response characteristics of low frequency modes. Dynamic behaviors in the out of plane are also studied.

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평판형 유전체 장벽 방전 반응기에서 충진물질에 따른 아세토나이트릴의 분해 특성 (Decomposition of Acetonitrile Using a Planar Type Dielectric Barrier Discharge Reactor Packed with Adsorption and Catalyst Materials)

  • 김관태;송영훈;김석준
    • 한국대기환경학회지
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    • 제19권2호
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    • pp.157-165
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    • 2003
  • A combined process of non-thermal plasma and catalytic technique has been investigated to treat $CH_3$CN gas in the atmosphere. A planar type dielectric barrier discharge (DBD) reactor has been used to generate the non-thermal plasma that produces various chemically active species, such as O, N, OH, $O_3$, ion, electrons, etc. Several different types of the beads. which are Molecular Sieve (MS) 5A, MS 13X, Pt/alumina beads, are packed into the DBD reactor, and have been tested to characterize the effects of adsorption and catalytic process on treating the $CH_3$CN gas in the DBD reactor. The test results showed that the operating power consumption and the amounts of the by-products of the non-thermal plasma process can be reduced by the assistance of the adsorption and catalytic process.

UV 임프린트 공정을 이용한 평판형 광도파로 기반의 집적형 분광 모듈 제작 (Fabrication of Monolithic Spectrometer Module Based on Planar Optical Waveguide Platform using UV Imprint Lithography)

  • 오승훈;정명영;김환기;최현용
    • 마이크로전자및패키징학회지
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    • 제22권3호
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    • pp.73-77
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    • 2015
  • 본 논문에서는 저가로 쉽게 제작할 수 있는 구조를 지닌 단일칩 형태의 고분자 기반 평판형 분광모듈을 제안하였다. 제안된 분광모듈은 UV 임프린트 기법에 의해 제작되어진 비등간격 나노회절격자와 오목거울이 포함된 평판형 광도파로로 구성되어진다. 회절효율을 향상시키기 위해 나노회절격자의 구조는 $25^{\circ}$의 블레이징 각도와 100nm의 선폭을 가지도록 설계, 제작되었다. 평판형 분광모듈은 700 nm 대역폭과 10 nm 분해능을 가짐을 확인하였다. 이러한 집적형 고분자 분광모듈은 다양한 센서 시스템에 적용될 수 있을 것으로 기대된다.

미세입자 분사가공을 위한 3 차원 임의형상 모재용 마스크 모델링 (Mask Modeling of a 3D Non-planar Parent Material for Micro-abrasive Jet Machining)

  • 김호찬;이인환;고태조
    • 한국정밀공학회지
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    • 제27권8호
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    • pp.91-97
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    • 2010
  • Micro-abrasive Jet Machining is one of the new technology which enables micro-scale machining on the surface of high brittle materials. In this technology it is very important to fabricate a mask that prevents excessive abrasives not to machine un-intend surface. Our previous work introduced the micro-stereolithography technology for the mask fabrication. And is good to not only planar material but also for non-planar materials. But the technology requires a 3 dimensional mask CAD model which is perfectly matched with the surface topology of parent material as an input. Therefore there is strong need to develop an automated modeling technology which produce adequate 3D mask CAD model in fast and simple way. This paper introduces a fast and simple mask modeling algorithm which represents geometry of models in voxel. Input of the modeling system is 2D pattern image, 3D CAD model of parent material and machining parameters for Micro-abrasive Jet Machining. And the output is CAD model of 3D mask which reflects machining parameters and geometry of the parent material. Finally the suggested algorithm is implemented as software and verified by some test cases.

Polytope와 graph에 관하여 (On polytopes and graphs)

  • 김연식
    • 한국수학교육학회지시리즈A:수학교육
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    • 제10권2호
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    • pp.4-8
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    • 1972
  • We consider the class (equation omitted) of all k-degenerate graphs, for k a non-negative integer. The class (equation omitted) and (equation omitted) are exactly the classes of totally disconnected graphs and of forests, respectively; the classes (equation omitted) and (equation omitted) properly contain all outerplanar and planar graphs respectively. The advantage of this view point is that many of the known results for chromatic number and point arboricity have natural extensions, for all larger values of k. The purpose of this note is to show that a graph G is (P$^3$)-realizable if G is planar and 3-degenerate.

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굴곡진 도로에서의 구간 선형 모델을 이용한 차선 검출 (Lane Detection on Non-flat Road Using Piecewise Linear Model)

  • 정민영;김경환
    • 한국통신학회논문지
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    • 제39A권6호
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    • pp.322-332
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    • 2014
  • 본 논문에서는 굴곡진 도로를 구간 선형 모델로 근사화한 차선 검출 알고리즘을 제안한다. 기존의 차선 검출 알고리즘들은 지표면이 평면이라는 가정을 이용하기 때문에, 도로면이 굴곡진 실제 도로에서는 강건한 차선 검출이 어렵다. 제안하는 방법에서는 이 문제를 전체 차로를 구간으로 분할하고, 각 구간 내에서 차로를 가장 잘 근사하는 평면 차로를 구함으로써 해결한다. 이를 위해 각 구간 내에서 다양한 각도와 위치를 가지는 평면 형태의 구간 차로 후보들을 생성하였다. 구간 차로 후보들의 연결 조합 중 실제 차로에 가장 가까운 조합을 다이나믹프로그래밍을 이용하여 찾음으로써 굴곡진 차로를 근사한다. 평면 도로 뿐 아니라, 상하, 좌우의 굴곡이 있는 도로 영상으로 구성된 데이터세트에 대하여 제안하는 방법의 차선 검출 성능을 검증하였다. 평면 도로를 가정한 기존의 방법들이 80%에서 90% 초반의 검출률을 보이는 반면, 제안하는 방법은 90% 후반의 검출률을 보임을 통해 굴곡진 도로에서의 차선 검출의 강건성을 입증하였다.

평판형 유전체 장벽 방전 반응기에서 Acetonitrile의 분해 특성 (Decomposition of Acetonitrile by Planar Type Dielectric Barrier Discharge Reactor)

  • 송영훈;김관태;류삼곤;이해완
    • 한국군사과학기술학회지
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    • 제5권3호
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    • pp.105-112
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    • 2002
  • A combined process of non-thermal plasma and catalytic techniques has been investigated to treat toxic gas compounds in air. The treated gas in the present study is $CH_3$CN that has been known to be a simulant of toxic chemical agent. A planar type dielectric barrier discharge(DBD) reactor has been used to generate non-thermal plasma that produces various chemically active species, O, N, OH, $O_3$, ion, electrons, etc. Several different types of adsorbents and catalysts, which are MS 5A, MS 13X, Pt/alumina, are packed into the plasma reactor, and have been tested to save power consumption and to treat by-products. Various aspects of the present techniques, which are decomposition efficiencies along with the power consumption, by-product analysis, reaction pathways modified by the adsorbents and catalysts, have been discussed in the present study.

아세톤 PLIF를 이용한 가스터빈 연소기 버너 출구 연료분포의 정량적 측정 (Quantitative Acetone PLIF Measurement of Fuel Distribution in a Gas Turbine Combustor Burner)

  • 전우진;김형모;이강엽;양수석
    • 한국연소학회지
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    • 제15권4호
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    • pp.43-52
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    • 2010
  • A non-intrusive measurement, Planar Laser Induced Fluorescence was employed to visualize and measure the fuel distribution of the non-reacting field at the burner exit of gas turbine combustor. Measurement techniques, image processing method and quantification procedure were presented. Also, concentration measurement with gas analyzer was carried out to verify the propriety of PLIF result. The PLIF result coincides well with gas analyzer measurement result. PLIF test result for several other conditions are mentioned as well.

이산와류법을 사용한 비평면 지면 와류전개 연구 (Study on the Wake Evolution on the Non-Planar Ground Using a Discrete Vortex Method)

  • 한철희
    • 융복합기술연구소 논문집
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    • 제6권2호
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    • pp.21-24
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    • 2016
  • Accurate simulation of wakeshapes behind a wing is important for the performance prediction of the aircraft and the wake hazard problem in the airport. In the present study, wakeshapes behind a wing inside tunnels are simulated in regard to the development of wing-in-ground effect vehicles. A discrete vortex method with a nonplanar ground modelling is used for the simulation. It was found that the wingtip vortices move toward outboard directions when the wing is in ground effect. When the wing is placed inside tunnels, the wingtip vortices move along the tunnel wall with counter clockwise direction. As the gap between the wingtip and the tunnel decreases, the wingtip vortices move further along the tunnel wall. Both vortices from bothsides of the wing will murge, which will be studied in future using a viscous computation.