• 제목/요약/키워드: Slow light

검색결과 206건 처리시간 0.031초

종/횡운동 coupling 상태에 대한 비행역학 연구 (Study on dynamics of the cross-couplig phenomenon between longitudinal and lateral motion)

  • 김성관;하철근
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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    • pp.1300-1303
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    • 1996
  • In this paper a typical problem is examined that a light, general aviation airplane, such as Cessna or Navion, in gliding turn flight shows helical-dive phenomenon when pilots try to stop the descent by using elevator only. It is known from pilot's experience that in a certain flight trim it is impossible to recover from helical-dive by using elevator only. From this study it is shown that helical-dive phenomenon is involved with longitudinal/lateral dynamics coupling to airplane's aerodynamics. Also this phenomenon consists of three parts of flight dynamics; first of all, fast longitudinal motion occurs, then is followed by a little slow lateral motion, and finally logitudinal/lateral coupled motion is fully developed.

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CD-ROM 드라이브의 대물렌즈 입자오염이 Laser Diode의 Power와 Photo Diode의 RF Signal에 미치는 영향 (Effect of Particle Contamination on Objective Lens in a CD-ROM Drive on Laser Diode Power and Photo Diode RF Signal)

  • 배양일;황정호
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.1429-1434
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    • 2003
  • A number of dust particles are intruded into ODD(Optical disk drive) due to the flow caused by disk rotation and are adhered to a lens or disk surface. The space between the disk and the lens is being reduced. Someone indicates the problems of this drive that are relatively small data storing capacity and slow access time. In recent, the problems of this optical disk drive mentioned above are being solved by adding the speed of the disk's revolution, making the actuator high-speed or light, and making the beam spot size smaller than making the space narrow between disk and lens. These particle contamination affects seriously RF Signal, readout signal in an ODD. Especially, the affected parts by a particle contamination in an ODD's readout signal are objective lens and media.

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모바일 기기용 게임 개발을 위한 가변 인덱스 컬러 응용 (Applications of Variable Indexed Colors for Game Development of Mobile Devices)

  • 정종필;김치훈
    • 한국콘텐츠학회논문지
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    • 제8권11호
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    • pp.49-56
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    • 2008
  • PC나 콘솔 기반의 게임들은 탁월한 하드웨어 지원에 힘입어 화려한 3D 효과와 이펙트 등을 보여주고 있지만, 다양한 컨버전스 또는 모바일 기기들은 상대적으로 가벼운 하드웨어 사양과 배터리 시간의 한계 때문에 계산양이 적은 가벼운 게임들을 선호하고 있다. 이러한 하드웨어 상의 게임 제작에 있어 최소한의 그래픽 품질을 유지하는 것은 매우 중요하다. 본 논문에서는 인덱스 컬러(Indexed Color) 팔레트를 하드 웨어 사양을 극복하여 발전시킬 수 있는 방법으로 제안 한다.

단일 유연 링크 매니퓰레이터의 복합 퍼지 제어 (Composite Fuzzy Control of a Single Flexible Link Manipulator)

  • 김재승;이수한
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.353-353
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    • 2000
  • To control a light weight flexible manipulator, a composite fuzzy controller is proposed. The controller is designed based on two time scaled models. A singular perturbation technique is applied for deriving the models. The proposed controller, however, does not use the complex equilibrium manifold equations, which are usually needed in the controller based on the two time scaled models. The controller for a slow sub-model and a fast sub-model are T-S type fuzzy controllers, which use 3 linguistic variables for each sub-model. A step trajectory is used in simulations as a reference trajectory of joint motions. The results of simulations with the proposed controller show excellent damping of flexible motions compared to a controller with derivative control of flexible motions.

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分光光度法에 依한 Iodine 의 Pyridine 및 Quinoline 溶液의 硏究 (Spectrophotometric Studies of the Solution of Iodine in Pyridine and Quinoline)

  • 박종회
    • 대한화학회지
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    • 제6권1호
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    • pp.69-72
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    • 1962
  • Spectrophotometric studies have been made on the solutions of elementary iodine in pyridine and quinoline, in the absence of light. The results shown that triiodide ion is produced in both solutions with different rates, and that triiodide ion behaves differently in both solutions. Iodine reacts slowly with pyridine, giving rise to triiodide ion, which is relatively stable in this solvent, hereas, iodine reacts rapidly with quinoline, forming triiodide ion, which interacts further with the medium at slow rate. It has been thought that the difference of the behavior of triiodide ion in both solutions may be due to the stronger basicity of quinoline than pyridine.

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Optical Pipelined Multi-bus Interconnection Network Intrinsic Topologies

  • d'Auriol, Brian Joseph
    • ETRI Journal
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    • 제39권5호
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    • pp.632-642
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    • 2017
  • Digital all-optical parallel computing is an important research direction and spans conventional devices and convergent nano-optics deployments. Optical bus-based interconnects provide interesting aspects such as relative information communication speed-up or slow-down between optical signals. This aspect is harnessed in the newly proposed All-Optical Linear Array with a Reconfigurable Pipelined Bus System (OLARPBS) model. However, the physical realization of such communication interconnects needs to be considered. This paper considers spatial layouts of processing elements along with the optical bus light paths that are necessary to realize the corresponding interconnection requirements. A metric in terms of the degree of required physical constraint is developed to characterize the variety of possible solutions. Simple algorithms that determine spatial layouts are given. It is shown that certain communication interconnection structures have associated intrinsic topologies.

가변 인덱스 컬러를 이용한 뉴 미디어 기기용 게임 제작 방법 (Application of variable indexed colors for game development of portable (hand-held) devices)

  • 정종필;김치훈
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2008년도 춘계 종합학술대회 논문집
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    • pp.131-134
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    • 2008
  • PC나 콘솔 기반의 게임들은 탁월한 하드웨어 지원에 힘입어 화려한 3D 효과와 이펙트 등을 보여주고 있지만, 다양한 핸드헬드 기기들과 컨버전스 기기 그리고 모바일 기기들은 상대적으로 가벼운 하드웨어 사양, 배터리 시간의 한계 때문에 계산양이 적은 가벼운 게임들을 선호하고 있다. 이러한 하드웨어 상의 게임 제작에 있어 최소한의 그래픽 퀄리티를 유지하는 것은 매우 중요하다. 본 논문에서는 인덱스 컬러(Indexed Color) 팔레트를 용량의 변화 없이 하드웨어 사양을 극복하여 발전시킬 수 있는 방법을 제안 한다.

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How Environmental Agents Influence the Aging Process

  • Karol, Meryl H.
    • Biomolecules & Therapeutics
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    • 제17권2호
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    • pp.113-124
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    • 2009
  • Aging is a multifaceted biological process that affects all organs and organ systems of the body. This review provides an up-to-date analysis of this highly exciting, rapidly changing field of science. The aging process is largely under genetic control but is highly responsive to diverse environmental influences. The genes that control aging are those that are involved with cell maintenance, cell damage and repair. The environmental factors that accelerate aging are those that influence either damage of cellular macromolecules, or interfere with their repair. Prominent among these are chronic inflammation, chronic infection, some metallic chemicals, ultraviolet light, and others that heighten oxidative stress. Other environment factors slow the aging process. Included among these agents are resveratrol and vitamin D. In addition, dietary restriction and exercise have been found to extend human lifespan. The various mechanisms whereby all these agents exert their influence on aging include epigenetic modification, chromatin maintenance, protection of telomeres, and anti-oxidant defense, among others. The complex process of aging remains under continued, intense investigation.

Stress Corrosion Cracking Behavior of Cold Worked 316L Stainless Steel in Chloride Environment

  • Pak, Sung Joon;Ju, Heongkyu
    • 한국주조공학회지
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    • 제40권5호
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    • pp.129-133
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    • 2020
  • The outcomes of solution annealing and stress corrosion cracking in cold-worked 316L austenitic stainless steel have been studied using x-ray diffraction (XRD) and the slow strain rate test (SSRT) technique. The good compatibility with a high-temperature water environment allows 316L austenitic stainless steel to be widely adopted as an internal structural material in light water reactors. However, stress corrosion cracking (SCC) has recently been highlighted in the stainless steels used in commercial pressurized water reactor (PWR) plants. In this paper, SCC and inter granular cracking (IGC) are discussed on the basis of solution annealing in a chloride environment. It was found that the martensitic contents of cold-worked 316L stainless steel decreased as the solution annealing time was increased at a high temperature. Moreover, mode of SCC was closely related to use of a chloride environment. The results here provide evidence of the vital role of a chloride environment during the SCC of cold-worked 316L.

나노튜브 전극 기반 양자점 감응 태양전지 구현을 위한 투명한 상대전극 (Transparent Counter Electrode for Quantum Dot-Sensitized Solar Cells with Nanotube Electrodes)

  • 김재엽
    • 한국표면공학회지
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    • 제52권1호
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    • pp.1-5
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    • 2019
  • Anodic oxidized $TiO_2$ nanotube arrays are promising materials for application in photoelectrochemical solar cells as the photoanode, because of their attractive properties including slow electron recombination rate, superior light scattering, and smooth electrolyte diffusion. However, because of the opacity of these nanotube electrodes, the back-side illumination is inevitable for the application in solar cells. Therefore, for the fabrication of solar cells with the anodic oxidized nanotube electrodes, it is required to develop efficient and transparent counter electrodes. Here, we demonstrate quantum dot-sensitized solar cells (QDSCs) based on the nanotube photoanode and transparent counter electrodes. The transparent counter electrodes based on Pt electrocatalysts were prepared by a simple thermal decomposition methods. The photovoltaic performances of QDSCs with nanotube photoanode were tested and optimized depending on the concentration of Pt precursor solutions for the preparation of counter electrodes.