• 제목/요약/키워드: Dynamics behavior

검색결과 1,229건 처리시간 0.024초

분자동력학을 이용한 윤활유의 해석적 연구 (An analysis for lubricants via molecular dynamics)

  • 김종억;김용섭
    • 오토저널
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    • 제6권1호
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    • pp.46-54
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    • 1984
  • We applies Molecular Dynamics simulation technics to a system of Lennard-Jones potential interacting Argon liquid to study shear flow behavior. The thermodynamic state of the system is .rho.=35.54 Kg, mole/m$^{3}$, T=86.5.deg. K which is the triple point of Argon liquid. We applies shear rate : .epsilon.=9.26*10$^{9}$ 1/sec in the system. We find the response function, shear viscosity changes, and shear rate build-up as a function of time. We also find the thermal conductivity in a soft-sphere system.

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인과지도의 시뮬레이션 방법론: NUMBER (A Simulation Method of Causal Maps: NUMBER)

  • 김동환
    • 한국시스템다이내믹스연구
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    • 제1권2호
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    • pp.91-111
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    • 2000
  • Causal maps or cognitive maps have been widely used to get insights for complex systems or decision makers. When insights come from the system behavior rather than its structure, we need simulation of causal maps and cognitive maps. In this paper, a method for directly converting causal maps and cognitive maps into stock-flow diagrams that can be simulated in computers in proposed. This method is called as NUMBER. NUMBER is an abbreviation for 'Normal Unit Modeling By Elementary Relationship'. In this paper, NUMBER is applied to a cognitive map of policy maker to show its usefulness.

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3차원에서의 열차 충돌사고 시뮬레이션 연구 (Simulation of Train Crashes in Three Dimensions)

  • 한형석;구정서
    • 한국철도학회논문집
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    • 제5권3호
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    • pp.187-195
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    • 2002
  • It is important to predict the crash behavior of trains to improve their crashworthiness. This paper investigates the simulation of high-speed train crashes in three dimensions using multibody dynamics. At present, little is known about three-dimensional crash simulations. This study shows that it is possible to simulate overriding and lateral buckling, including results from one- or two-dimensional simulations. Several parameters, however, such as computational time and large deformation of structures, need further investigation.

Dynamics of an atomic wave packet in a standing wave quantized field

  • Tak, Jo-Yeong;Won, An-Gyeong
    • 한국광학회:학술대회논문집
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    • 한국광학회 2001년도 제12회 정기총회 및 01년도 동계학술발표회
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    • pp.252-253
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    • 2001
  • The purpose of this work is to investigate the dynamics of an atomic wave packet whose center-of-mass motion is quantized in a resonant standing wave cavity field. The mechanical aspect of the matter-field interaction has been extensively studied In the theme of atomic beam deflection, diffraction, or reflection by a standing-wave field. The effect caused in the behavior of spontaneous emission by the atomic center-of-mass motion, classical and quantized, in a standing wave cavity mode has been studied, and recently the one-atom laser with quantized atomic center-of-mass motion has been investigated. (omitted)

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기가헤르츠 오실레이터를 위한 BN 나노튜브 연구 (A study on a Boron-Nitride Nanotube as a Gigahertz Oscillator)

  • 이준하
    • 반도체디스플레이기술학회지
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    • 제6권1호
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    • pp.27-30
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    • 2007
  • The gigahertz oscillator behavior of double-walled boron-nitride nanotube (BNNT) was investigated by using classical molecular dynamics simulations. The BNNT oscillator characteristics were compared to carbon-nanotube (CNT) and hybrid-C@BNNT oscillators. The results show that the BNNT oscillators are higher than the van der Waals force of the CNT oscillator. Since the frictional effects of BNNT oscillators are higher than that of a CNT oscillator, the damping factors of BNNT and hybrid oscillators are higher than that of a CNT oscillator.

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Leucine Zipper as a Fine Tuner for the DNA Binding; Revisited with Molecular Dynamics Simulation of the Fos-Jun bZIP Complex

  • 최용훈;양철학;김현원;정선호
    • Bulletin of the Korean Chemical Society
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    • 제20권11호
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    • pp.1319-1322
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    • 1999
  • Leucine zipper dynamically tunes the degree of bifurcation of the DNA binding segments in the basic region of the Fos-Jun bZIP complex. Molecular dynamics simulation indicated that site-specific mutagenesis of conserved leucine residues inside the leucine zipper domain caused the change of dynamic behavior of the basic region, and efficient DNA binding occurs only within a certain range of distance between the two DNA binding segments in the basic region. Distribution of α-helices in the hinge region is also suggested to influence the bifurcation of the DNA binding segments.

Verification and Application of MASTER for Load Follow Operation

  • Park, Yong-Soo;Cho, Byung-Oh;Lee, Chang-Ho;Jung, Yil-Sup;Park, Chan-Oh
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1996년도 춘계학술발표회논문집(1)
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    • pp.231-236
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    • 1996
  • The xenon dynamics module in the nuclear design code MASTER was verified through a simulation calculation. The simulation result shows that the xenon dynamics module in MASTER can trace and predict xenon behavior with accuracy under any core transient state and therefore can simulate load follow operations.

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탄소나노튜브의 역학적 거동에 관한 온도와 하중부하속도의 의존성 (Temperature and Loading-Rate Dependence on the Mechanical Behavior of Carbon Nanotubes)

  • 정병우;임장근
    • 대한기계학회논문집A
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    • 제30권7호
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    • pp.809-815
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    • 2006
  • The temperature and loading-rate dependence on the mechanical behavior of single-walled carbon nanotubes under axial compression and torsion is examined with classical molecular dynamics simulation. The critical buckling is found to depend on the temperature and loading-rate. The yielding under torsion is also found to depend on the temperature and loading-rate. But it is shown that the compression and torsional stiffness are independent of the varied temperatures and loading-rates.

차량 윈드실드용 전동 선바이저의 동특성 연구 (Dynamic Behavior of an Electric Sun Visor for Automotive Windshields)

  • 이석우;김권희;김정훈;한재웅
    • 한국정밀공학회지
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    • 제33권10호
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    • pp.857-864
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    • 2016
  • In this study, we proposed a novel concept of electric sun visor comprising a dark, see-through sun shade material that ensures unimpaired driver's vision with continuous control of the shade position. The shade extending from the windshield base along its surface may be subjected to severe vibration during driving unless the design parameters are carefully selected. A prototype was tested to collect acceleration data during driving. Based on the test data, an ADAMS dynamics model was validated. The mechanism of sun visor was optimized to minimize vibration based on the dynamics model, experimental design, and response surface method.

진동 유동장에서 유동공진에 의한 실린더 후류의 와류 특성 변화 (Change of Vortex Dynamics in the Cylinder Wake by the Lock-on to Oscillatory Incident Flow)

  • 김원태;성재용;유정열
    • 대한기계학회논문집B
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    • 제27권11호
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    • pp.1645-1654
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    • 2003
  • When vortex shedding is locked-on to a single frequency oscillatory flow, the variations of vortex dynamics are investigated using a time-resolved PIV system. Wake regions of recirculation and vortex formation, dynamic behavior of the shed vortices and the Reynolds stress fields are measured in the wake-transition regime at the Reynolds number 360. In the lock-on state, reduction of the wake region occurs and flow energy distributed downstream moves upstream being concentrated near the cylinder base. To observe the dynamic behavior of the shed vortices, the trajectory of the vortex center extended to the inside of the wake bubble is considered, which describes well the formation and evolution processes. The Reynolds stresses and their contributions to overall force balance on the wake bubble manifest the increase of the drag force by the lock-on.