• 한국정밀공학회지
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• 제17권12호
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• pp.209-216
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• 2000

The lateral behavior of the moving web is critical to the quality of the web products. The alignment of the rollers carrying the web is found to be one of important factors to the lateral behavior of the moving web. But, the study on the effect of the tilting roller in the direction of the normal to the moving web on the lateral behavior has not been reported in the literature yet. For example, the contact roller often contacts the winding roll in a tilted fashion and causes the lateral motion of the winding web, which induces the offset on the wound roll. The lateral dynamics of the moving web induced by a tilted roller in normal direction of a web is investigated in this paper. The two-dimensional dynamic model developed by Shelton is extended to investigate the effect of a titled roller in a normal direction of the moving web on the lateral motion of the moving web. New boundary conditions are developed to solve the extended model. Computer simulation study proved that the model developed can be used to predict the lateral motion of the moving web ？ to a tilted roller in normal direction of the moving web. The lateral deflection is increased exponentially a the tilting angle is increased. As the length of web span is increased, the amount of lateral deflection was increased almost linearly for the same tilting angle. The lateral dynamics turned out to be almost independent to the operating tension. The model developed can be used to solve the offset problem of the staggered winding and also to design a new web guiding mechanism.

• 한국소음진동공학회논문집
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• 제14권12호
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• pp.1304-1313
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• 2004

In this paper a dynamic behavior of a cracked cantilever pipe conveying fluid with the moving mass is presented. It has the results focused on the frequency change. Based on the Euler-Bernouli beam theory, the equation of motion can be constructed by using the Lagrange's equation. The crack section is represented by a local flexibility matrix connecting two undamaged beam segments. The crack is assumed to be in the first mode of fracture and to be always opened during the vibrations. When the velocity of the moving mass is constant, the influences of the crack severity, the position of the crack, the moving mass, and the coupling of these factors on the frequencies of the cantilever pipe are depicted.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 추계학술대회논문초록집
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• pp.315.2-315
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• 2002

The vibrational system of this study consists of a cantilever pipe conveying fluid, the moving mass upon it and an attached tip mass. The equation of motion is derived by using Lagrange equation. The influences of the velocity of moving mass and the uniformly distributed tangential follower force have been studied on the dynamic behavior of a cantilever pipe by numerical method. While the moving mass moves upon the cantilever pipe, the velocity of fluid flow increase, the tip displacement of cantilever pipe conveying fluid is decreased. (omitted)

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 춘계학술대회논문집
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• pp.701-705
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• 2000

On the dynamic behavior of a simple beam subjected to an uniformly distributed tangential follower force, the influences of the velocities and magnitudes of a moving mass have been studied by numerical method. The instant amplitude of a simple beam is calculated and analyzed for each position of the moving mass represented by the time functions. The uniformly distributed tangential follower force is considered in its critical value of a simple beam, and four values of velocity is also chosen. Their coupling effects on the deflections of a simple beam are inspected too. When a moving mass moves after middle zone of a simple beam at the low velocities, its deflection is increased by the coupling of an uniformly distributed tangential follower force and moving mass.

• 한국재난정보학회 논문집
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• 제13권2호
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• pp.258-266
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• 2017

사장교는 특수목적으로 장 경간을 갖는 교량이다. 긴 경간으로 인하여 차량의 이동하중에 대한 동적응답이 매우 특별하다. 거동역시도 비선형을 갖고 있어 설계에 어려움이 많은 형식이다. 연구에서 다양한 차량하중을 고려하여 사장교의 응답을 구하고 장 경간 교량의 이동하중에 대한 거동을 파악한다. 특히, 한 방향과 양방향에 대한 하중이 속도를 가지고 이동할 때 교량의 부재에 대한 거동은 케이블의 유연성에 기인하는 것으로 나타났다. 차량하중의 영향은 케이블의 진동과 함께 수직변형을 증폭하는 경향을 나타내므로 케이블과 바닥판의 동적거동을 포함한 분석이 보다 효과적임을 알 수 있다.

• 한국통신학회논문지
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• 제36권6B호
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• pp.697-709
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• 2011

차량과 같은 이동환경에서 무선 인터넷 서비스를 사용할 때, 불필요하게 발생하는 핸드오버는 서비스 품질 저하와 시그널링 오버헤드를 유발하여 실시간 멀티미디어 서비스 제공에 단점으로 작용한다. 본 논문에서는 Mobile Node (MN)가 일정한 이동패턴을 가지고 있을 때, Mobility behavior profile을 이용하여 생성한 DTMC을 이용하여 핸드오버의 발생 횟수를 감소시켜 무선 인터넷 서비스를 향상시킬 수 있는 핸드오버 방법을 제안한다. 기존 핸드오버 방법을 반복적으로 수행하며 Mobility behavior profile을 학습하고, Mobility behavior profile 에 충분한 양이 학습되면 Mobility behavior profile을 이용하여 DTMC의 1-step & 2-step transition probability matrix를 생성한다. 그 이후에는 DTMC의 1-step & 2-step transition probability matrix를 이용하여 핸드오버를 수행하며 Mobility behavior profile을 계속 업데이트한다. 4개의 Mobility model에서의 실험을 통하여 평균 핸드오버 횟수와 평균 RSSI값, 그에 따른 Throughput을 비교한다.

• Journal of international Conference on Electrical Machines and Systems
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• 제3권4호
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• pp.394-397
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• 2014

This paper deals with the comparison and dynamic behavior of a moving-coil linear oscillatory actuator (MCLOA) with/without a mechanical spring. On the basis of a dynamic simulation model, the dynamic characteristics such as a current and a stroke of the MCLOA without the spring are predicted for various values of frequency. And then, dynamic test results are given to confirm the dynamic simulations. Finally, this paper describes the influence of the spring on the dynamic behavior of the MCLOA from the dynamic experiments of the MCLOA with/without the spring.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 춘계학술대회논문집
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• pp.689-694
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• 2003

An iterative modal analysis approach is developed to determine the effect of transverse open cracks on the dynamic behavior of simply supported pipe conveying fluid subject to the moving mass. The equation of motion is derived by using Lagrange's equation. The influences of the velocity of moving mass and the velocity of fluid flow and a crack have been studied on the dynamic behavior of a simply supported pipe system by numerical method. The presence of crack results in higher deflections of pipe. The crack section is represented by a local flexibility matrix connecting two undamaged beam segments i.e. the crack is modelled as a rotational spring. Totally, as the velocity of fluid flow and the crack severity are increased, the mid-span deflection of simply supported pipe conveying fluid is increased. The time which produce the maximum dynamic deflection of the simply supported pipe is delayed according to the increment of the crack severity.

• 대한기계학회논문집A
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• 제27권11호
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• pp.1815-1823
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• 2003

The vibrational system of this study consists of a cantilever pipe conveying fluid, the moving masses upon it and having an attached tip mass. The equation of motion is derived by using Lagrange's equation. The influences of the velocity and the inertia force of the moving mass and the velocities of fluid flow in the pipe have been studied on the dynamic behavior and the natural frequency of a cantilever pipe by numerical method. The deflection of the cantilever pipe conveying fluid is increased due to the tip mass and rotary Inertia. After the moving mass passed upon the cantilever pipe, the amplitude of pipe is influenced by energy variation when the moving mass fall from the cantilever pipe. As the moving mass increase, the frequency of the cantilever pipe conveying fluid is increased. The rotary inertia of the tip mass influences much on the higher frequencies and vibration mode.

• 설비공학논문집
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• 제10권1호
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• pp.33-43
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• 1998

Dynamic behavior of a scroll compressor has been investigated analytically. The equations of motion of moving elements of the scroll compressor such as the orbiting scroll, anti-rotation device, slider bush, and the crank shaft with eccentric crank pin have been set up. As the solutions of these equations, reaction forces between the moving elements, and also between the moving elements and the compressor frame have been calculated. The reaction forces from the moving elements to the frame are the unbalanced forces, which produce accelerations of the compressor body. These accelerations can be used as a measure of the compressor vibration. The major contributions to the unbalanced forces come from the orbiting movement of the orbiting scroll.