• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.47-49
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• 2007

This paper deals with the generating characteristic analysis of permanent magnet (PM) machines with multi-pole rotor and 3-phase stator windings considering losses such as copper loss, iron loss and mechanical loss. First, using d-q transformation, dynamic equations of PM machines are established. And then, characteristic equations for losses, power and efficiency are also derived. On the basis of d-q dynamic equations and characteristic equations, dynamic simulation algorithm is achieved by the MATLAB/SIMULINK. The simulation results are validated extensively by finite element (FE) analyses.

• Tribology and Lubricants
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• 제17권2호
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• pp.116-123
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• 2001

A theoretical analysis has been undertaken to show the influence of bearing geometry on the steady state characteristics of air lubricated spherical tilting pad bearings. The geometry variations considered are the number of pads, the eccentricity ratio, the direction of load, and the preloading. Dynamic characteristic equations are derived with pad assembly method.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2012년도 춘계학술대회 논문집
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• pp.748-754
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• 2012

In this paper free vibration analysis of symmetric and cross-ply elastic laminated shells based on FSDT was performed through discretization of equations of motion and boundary condition. Model of laminated composite shells subjected to a combination of magnetic and thermal fields is developed. These coupled equations of motion are based on the electromagnetic equations (Faraday, Ampere, Ohm, and Lorenz equations) and thermal equations which are involved in constitutive equations. Dynamic characteristic of composite shells for change of magnetic fields is investigated.

• 한국도로학회논문집
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• 제7권2호
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• pp.57-67
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• 2005

거의 대부분의 문헌에서 아스팔트바인더의 유동거동을 다룰 때, 단일상 균일 유체로 일률적으로 취급하는데 이로 인한 오류가 심각하다. 본 연구에서는 개질이던 스트레이트이던 아스팔트바인더의 유동과 관련된 특성방정식을 모두 소개하고, 특히 다상 불균일 유체의 특성방정식을 새로이 소개한다. 이러한 식들의 특징 이 무엇인지를 실제 측정된 아스팔트바인더의 동전단시험 데이터를 이용하여 설명한다 특히 단일상 균일 유체와 다상 불균일 유체와의 거동차이전과 특성방정식의 차이점에 대해 집중 부각한다. 이러한 차이는 아스팔트유체를 다룰 때 어떠한 특성방정식을 사용해야 하며,특정 바인더를 분석하기 위해서는 어떤 물성을 조사해야 하는 지에 대해서 이해하게 한다. 본 연구는 개질바인더의 분석과 등급제정에 필수적인 정보를 제공한다.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1993년도 제18회 학술대회 초록집
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• pp.63-69
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• 1993

In this paper the characteristics of Hydrostatic Bearing of piston of cylinder are investigated . The dynamic characteristic equations of piston considering both parallel and rotational motion and time dependent modified Reynolds Equation are analyzed and the dynamic pressure distribution of oil film is numerically calculated by perturbation method and finite difference method. and the atatic analysis is carried out. so, the influence of design parameter of piston on the characteristic of bearing is analyzed.

• Journal of Electrical Engineering and Technology
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• 제2권3호
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• pp.346-352
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• 2007

In this paper, we present an analysis of dynamic characteristics of an electromagnetic actuator for circuit breakers. It is indispensable to simultaneously analyze magnetic, electric, and mechanical phenomena to obtain the dynamic characteristics of the electromagnetic actuator because these phenomena are closely related to each other in an electromagnetic actuator system. The magnetic equations are computed by using the finite element method (FEM). The electric equations and the mechanical equations, which include the time derivative terms, are calculated by using the time difference method (TDM). The calculated results, which have been obtained by means of the FEM and the TDM, are presented with experimental data.

• 한국자기학회지
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• 제10권1호
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• pp.42-47
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• 2000

본 논문에서는 원관내 횡방향 자장을 인가한 경우에 자성유체의 유동을 이론적으로 연구하였다. 이론식 도출에 있어서 Eringen의 극성이론과 Shliomis에 의해 유도된 지배방정식을 사용했다. 자기적 응답으로서 속도, 와도, 각속도의 분포 및 이론식을 통해서 자성유체는 비뉴우톤 유체임을 나타낸다. 또한, 인가자장이 종방향일때와 비교해서 자성유체의 동적특성을 조사한다. 즉, 자성유체에 영향을 주는 자장의 범위를 극성, 치수 및 자성효과 파라미터를 이용해서 조사한다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 춘계학술대회 논문집
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• pp.565-568
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• 2002

Welding variables and conditions in gas metal arc welding (GMAW) effect on the weld quality and productivity, extensive research efforts have been made to analyze the welding variables and conditions. In this study dynamic behavior of GMAW system is investigated using the characteristic equations of the power supply, wire and welding arc. Characteristic equation of wire is modified to include the effect of droplets attached at the electrode tip. The dynamic characteristics of arc length, current, voltage with respect to the step, ramp inputs of CTWD was simulated, seam tracking procedure using arc sensor was simulated with variable V-Groove geometries and weaving frequencies. From results of simulation, some predictions about dynamic characteristics of GMAW and welding process are available. The proposed simulator and results appear to be utilized to determine the proper welding conditions, to be improved by considering power supply dynamic characteristics.

• 한국산업융합학회 논문집
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• 제4권2호
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• pp.207-213
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• 2001

Welding variables and condition in gas metal arc welding (GMAW) effect on the weld quality and productivity, extensive research efforts have been made to analyze the welding variables and conditions. In this study dynamic behavior of GMAW system is investigated using the chararcteristic equations of the power supply. wire and welding arc. Characteristic equation of wire is modified to include the effect of droplets attached at the electrode tip. The dynamic characteristics of arc length, current, voltage with respect to the step, ramp inputs of CTWD was simulated. From results of simulation, some predictions about dynamic characteristics of GMAW and welding process are available. The proposed simulator and results appear to be utilized to determine the proper welding conditions, to be improved by considering power supply dynamic characteristics.

• 한국소음진동공학회논문집
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• 제17권7호
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• pp.579-586
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• 2007

Analytical method to analyze the effect of tolerance on the modal characteristic of multi-body systems in dynamic equilibrium position is suggested in this paper. Monte-Carlo method is conventionally employed to perform the tolerance analysis. However, Monte-Carlo method spends too much time for analysis and has a greater or less accuracy depending on sample condition. To resolve these problems, an analytical method is suggested in this paper. Sensitivity equations for damped natural frequencies and the transfer function are derived at the dynamic equilibrium position. By employing the sensitivity information of mass, damping and stiffness matrices, the sensitivities of damped natural frequencies and the transfer function can be calculated.