• 제목/요약/키워드: Natural Movement

검색결과 714건 처리시간 0.027초

갠트리형 3축 이송계의 동특성 평가 및 개선 연구 (Evaluation and Improvement of Dynamic Characteristics of 3-axis Gantry-type Stage)

  • 박상원;;서용규;홍성욱
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2006년도 춘계학술대회논문집
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    • pp.219-223
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    • 2006
  • This paper presents a gantry type 3-axes positioning system, which is useful to test control algorithms for coordinate measuring machines and industrial cranes. The dynamic characteristics of the system have been investigated through a series of finite element analysis and experiments. In order to minimize the residual vibration during movement, this paper implements input shaping algorithms for the system with the information from the dynamic analysis. The results show that the dynamic performance of the system can be significantly improved by the dynamic analysis and implementation of input shaping

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PRELIMINARY STUDY OF WATER CONTENTS AND SIGNAL BEHAVIOR IN FINGERNAIL/EPR DOSIMETRY

  • Choi, Hoon;Choi, Sul A;Lee, Byungil
    • Journal of Radiation Protection and Research
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    • 제38권4호
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    • pp.185-188
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    • 2013
  • Heating method using electric heater was used to reduce water content in fingernail clippings. Authors found that low water content is helpful to measure EPR signal of fingernail sample with enhanced variability. Generally, natural dehydration happens in normal room condition at least one month and needs much time for using in experiment. So, artificial heating method is applied in this study for time savings. Fingernail samples were tested to find effect of water content to the EPR signal on microwave power levels for dosimetry. Low water content in fingernail reduced variability of EPR signal and makes it possible to measure accurate EPR signal. It also made it possible to measure constant movement of EPR signals on several microwave power levels. Although this method was difficult to apply directly in fingernail/EPR dosimetry, we, authors, believe that this heating method would be useful to differentiate MIS2 and RIS which are generally located at the same g-factor and almost impossible to be identified with each other.

선회류에서 화염 핵 발달에 대한 실험적 연구 (Experimental study on flame kernel development in swirling flow)

  • 유준;배충식
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2001년도 제17회 학술발표회 논문초록집
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    • pp.50-53
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    • 2001
  • Flame propagation during the initial stages of ignition in a non-premixed swirl, having some of characteristics of the primary zone of an aero gas turbine combustor, has been investigated. Nd:YAG laser was adopted as the principal ignition source to allow arbitrary placing of the ignition site i subsequent flame development was monitored using a natural light high speed filming technique for many ignition site at two different swirl ratios and an overall equivalence ratio of 0.9. For ignition offset from the burner centreline, buoyancy force associated with radial pressure gradient produced a strong inward movement of the flame kernel. At the burner exit. flame kernels invariably developed into cylindrical form and a 'radial confinement /axia expansion' (RCAE) process was observed.

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CAPM에서 $\beta$계수이외의 변수가 시장의 이상현상에 미치는 영향 (The effect of the variables with the exception of $\beta$ on and abnormal phenomenon of the stockmarket in CAPM)

  • 이재범
    • 대한안전경영과학회지
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    • 제1권1호
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    • pp.231-239
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    • 1999
  • CAPM explains the rate of return for the risk asset by $\beta$, systematic risk. There are some assumption in CAPM. But CAPM can not explain the movement of stock price sufficiently due to limitation of the assumptions. Therefore many scholars study which variables with the exception of $\beta$ effect on the rate of return of risk asset for supplementing this limitation by using PER, size of firm etc.. But it will be natural that PER, size of firm etc. to be determinant factors of $\beta$ also effect on the abnormal rate of return, because PER, size of firm etc. used in their studies already effect on determination of $\beta$, . That is, the determinant factors of $\beta$ effect on determination of abnormal rate of return according as $\beta$, effects on abnormal rate of return. Therefore, this study tests empirically how the determinant factors of $\beta$, effect on determination of$\beta$, ,and how $\beta$ and the determinant factor of $\beta$ effect on the abnormal rate of return in CAPM.

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터널브라킷 애자류 오염도 분석에 관한 연구 (A research on the Tunnel bracket insulator pollution characteristic in Korea Railroad)

  • 전용주;류영태;박영식;박기범;이태훈
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2009년도 춘계학술대회 논문집
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    • pp.1963-1969
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    • 2009
  • This paper introduces method to estimate pollutant negative influence to polymer type insulator according to the international standard. To accomplish this goal, effective sample collecting method was surface was collected directly with the same dimension. Distilled Through this method pollute is easily and accurately collected. The second step is pollutant analysis. Several analyze item is selected such as quantity, conductivity, contact angle, Optical Microscope(OM), IR spectrometer(FT-IR), Equivalent Salt Deposit Density(ESDD), Thermal Analyzer(TA) and ICP-AES. The third step, best represent tunnel was selected considering location, length and natural surroundings. Also to consider the difference at inside the tunnel, several bracket insulators were selected along to the location. To make the result precise, above procedure was repeated several times at the same target. Finally relation among type of train, numbers of movement, surroundings, length will be considered in combination with the pollution. With this result pollute map for KORAIL could be accomplished and inspect period will be optimized case by case.

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Modelling of Swimming Ability Limits for Marine Fish

  • KIM Yong-Hae;WARDLE Clement S.
    • 한국수산과학회지
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    • 제30권6호
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    • pp.929-935
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    • 1997
  • The total energy of fish movement and the maximum burst swimming speed were estimated and formulated in accordance with body length and water temperature for several species in fisheries by empirical methods and also by using published results. Under the assumption of swimming energy reserve of a fish at the initial rest state, the swimming endurance of fish with different body lengths, swimming speeds and angular velocity was calculated using the relevant equations under similar conditions in tank experiments as well as natural conditions in field. Relative swimming energy efficiency or the transition swimming speed between red and white muscle for energy consumption was represented as a trigonometric function of swimming speed ratio. Therefore, this model does closely approach the actual swimming abilities and their limits especially in relation to the fishing gear operation and allow for the greater vitality of the wild fish in the fields.

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15 Park Row New York City - 120 Years Later, Still Relevant in Contextualism and Sustainability

  • Karahan, Beyhan
    • 국제초고층학회논문집
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    • 제9권1호
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    • pp.61-70
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    • 2020
  • After the 1884 Home Insurance building in Chicago and 1889 Tower building in New York, 15 Park Row became the tallest building in the USA in 1899 and it held this record for nine years. Completed just before the arrival of the 20th century, this building deserves to be recognized for the sophistication of its architecture with respect to contextual understanding of the 19th century historic texture in Lower Manhattan, its uniquely economical floor plans, and its use of natural ventilation and daylight. The compositional techniques using the proportional analysis of its context reflect the highest level of architectural education of its time by its architect Robert H. Robinson. In addition, it also offers a unique glimpse to the state-of-the-art technology of its time regarding its structure, its use of movement systems that was capable of serving 4000 users.

전자력을 받는 외팔보의 비선형진동 (Nonlinear Vibration of a Cantilever Beam Subjected to Electromagnetic Forces)

  • 최연선;서경석;우영주
    • 대한기계학회논문집A
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    • 제27권1호
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    • pp.48-57
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    • 2003
  • This study presents nonlinear vibration of a cantilever beam subjected to electromagnetic forces. The dynamic responses of the beam show various nonlinear phenomena with the variation of the system parameters, such as the jump phenomenon, multiple solutions, and the movement of the natural frequency. In this study the nonlinear stiffness due to electromagnetic forces which depends on air gap size is measured experimentally, and the system is modeled by a single degree of freedom nonlinear dynamic system and solutions are solved numerically. The numerical results show good agreements with the experimental results, which demonstrate the nonlinearity of electromagnetic force. Finally the occurrences of the jump phenomenon and the first, second and fourth harmonic components are confirmed in using the method of multiple scales.

주관절 운동의 상완·전완좌표계 타당도 및 굴곡/신전과 회내/회외의 상호작용 (The Validity Test of Upper·Forearm Coordinate System and the Exploratory Analysis of the Interactive Effect between Flexion/Extension and Pronation/Supination during Elbow Joint Motion)

  • 김진욱
    • 한국운동역학회지
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    • 제20권2호
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    • pp.117-127
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    • 2010
  • The axes of upper forearm coordinate system have been considered as principal axis of each segment which was component of elbow joint. The purpose of this study was to verify whether the mean direction(principal axis) of instantaneous axes of rotation for pure flexion/extension motion coincided with the flexion/extension axis of upper forearm coordinate system. The same procedure was done for pronation/supination motion. Furthermore, it was tested indirectly that there was an interaction effect between the two rotational motions. The results showed that most segment coordinate axes statistically were not consistent with the mean directions of flexion/extension and pronation/supination axes of rotation. From the results, it would be concluded that the ISB coordinate systems was proved to be a little valid for human movement analysis. There also was an effect of pronation/supination angles on flexion/extension motion.

Swarm Group Mobility Model for Ad Hoc Wireless Networks

  • Kim, Dong-Soo S.;Hwang, Seok-K.
    • Journal of Ubiquitous Convergence Technology
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    • 제1권1호
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    • pp.53-59
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    • 2007
  • This paper proposes a new group mobility model for wireless communication. The mobility model considers the psychological and sociological behavior of each node and the perception of other nodes for describing interactions among a set of nodes. The model assumes no permanent membership of a group, capable of capturing natural behaviors as fork and join. It emulates a cooperative movement pattern observed in mobile ad hoc networks of military operation and campus, in which a set of mobile stations accomplish a cooperative motion affected by the individual behavior as well as a group behavior. The model also employs a physic model to avoid a sudden stopping and a sharping turning.

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