• 대한기계학회:학술대회논문집
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• 대한기계학회 2002년도 학술대회지
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• pp.267-270
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• 2002

Combustion instability, which is one of the most undesirable phenomena in the development of liquid Propellant rocket engine, can cause serious damage to the rocket itself, and must be evaded by all means. Unfortunately, KSR-III rocket went through the combustion instability during engine start at the propulsion test article No.2. To resolve the problem, time sequence has been changed, and the baffle system has been applied. In consequence of the change, stable combustion was achieved.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 춘계학술대회논문집
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• pp.1122-1129
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• 2001

In this work, we propose a new type of HDD suspension featuring shape memory ally (SMA) actuator in order to prevent the contact between the slider and disk. The principal design parameters are obtained from the modal analysis using finite element analysis, and then the dynamic model is established to formulate the control scheme for Non-Contact Start/Stop mode drive. Subsequently, a robust Η$_{\infty}$, control algorithm is designed by integrating experimentally-obtained SMA actuator dynamics to the proposed suspension system. The controller is empirically realized and control results for different load/unload profiles are presented in time domain. In addition, the contact signal between the slider and disk is measured by the electrical resistance method.istance method.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1986년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 17-18 Oct. 1986
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• pp.200-204
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• 1986

Particle size distribution in a Continuous Mixed Suspension Mixed Crystal Removal (CMSMPR) crystallizer has been analyzed using the Population Balance (PB) model. This method presents difficulties when the growth rate of crystal depends on the crystal size. Recent studies indicate that in many cases the growth rate is dependent on size when the crystal sizes are small. In this study, a Residence Time Distribution(RTD) model was proposed to take the size dependence into account together with an appropriate numerical scheme. When compared with the approximate results based on PB model, RTD model results showed improvements also a nucleation effect which is normally unimportant for steady state analysis. Start-up data for NaCl-Water-Ethanol system was compared with computed values.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 하계종합학술대회 논문집(2)
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• pp.269-272
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• 2001

In this paper we proposed the format converter design and implementation for real time image processing. This design method is based on realized the large processor-per-pixel array by integrated circuit technology in which this two types of integrated structure is can be classify associative parallel processor and parallel process with DRAM cell. Layout pitch of one-bit-wide logic is identical memory cell pitch to array high density PEs in integrate structure. This format converter design has control path implementation efficiently, and can be utilized the high technology without complicated controller hardware. Sequence of array instruction are generated by host computer before process start, and instructions are saved on unit controller. Host computer is executed the pixel-parallel operation starting at saved instructions after processing start

• JSTS:Journal of Semiconductor Technology and Science
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• 제7권2호
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• pp.94-97
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• 2007

The desin and implementation of a CMOS analog integrated circuit that provides dual-mode modulations, PWM for active clamp reset converter and PFM for LLC resonant converter, is described. The proposed controller is capable of implementing programmable soft start and current-mode control with compensating ramp for PWM and frequency shifting soft start for PFM. Also it provides delay time for both modes. PWM mode is implemented by active clamp reset converter and PFM mode is implemented by LLC resonant convereter, respectively. The chip is fabricated using the 0.6um high voltage CMOS process.

• 한국도서관정보학회지
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• 제11권
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• pp.211-240
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• 1984

The Saemaul Mini-Library system had to start as a purely voluntary grass-roots movement without a tax su n.0, pport. In other words, it had to depend on voluntary contributions in time and labor by the reading club members for its finance and daily maintenance and operation. The purpose of the study is to analyse the actual condition of a Saemaul Mini-Library, which is established in a rural and a fishing village. To meet this purpose, I will survey the function and the meaning of a Saemaul Mini-Library and the main tendency of it-now did it start and how did it develop and I will analyse the general condition of structural factors (establishment, materials, reading club) in a Saemaul Mini-Library.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2006년도 전력전자학술대회 논문집
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• pp.43-45
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• 2006

대부분의 컨버터들은 초기 기동시에 MOSFET 전류와 전압의 과도한 상승을 막아주기 위해서 Soft Start 기능을 갖고 있다. 하지만 제어기 내부의 지연시간이나 LEB(Leading Edge Blanking) 시간 등으로 인해 MOSFET은 무시할 수 없는 상당한 기간의 최소 턴온 시간(Minimum Turn-on Time)을 갖게 되고, 이로 인해 드레인 전류가 과도하게 상승하는 현상을 보이게 된다. 본 논문에서는 이런 현상이 발생할 수 있는 초기 기동이나 출력단 단락시에 과도한 드레인 전류의 상승을 막아주는 방법을 제시하고자 한다.

• 동의생리병리학회지
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• 제19권3호
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• pp.600-604
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• 2005

Following are the view points from the Bioethics on the foundation of the theory of material basis & vital and mental activities (精氣神) ; the whole idenity of the human is observed both materially and morally. The questions of the start and origination on the human life are the principal subject on the bioethics, and therefore the opinions on the bioethics on the foundation of the theory of material basis & vital and mental activities (精氣神) persist that the start and origination on the human life is the time of fertilization. The social issues as the abortion and suicide must judged basically on the bioethics on the foundation of the theory of material basis & vital and mental activities (精氣神).

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
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• pp.1117-1119
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• 2005

The inductance is an important parameter in order to analyze steady state of LSRM(Line-start Synchronous Reluctance Motor). If FEM(Finite Element Method) is used to compute the parameter according to the change of flux barriers and conductor bars, less analysis time is required. Therefore, this paper adopts equivalent magnetic circuit method to simply calculates inductance, and the result is verified by comparing with the results by FEM.

• 대한안전경영과학회지
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• 제25권3호
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• pp.1-7
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• 2023

As the capacity of renewable power generation facilities rapidly increases, the variability of electric power system and gas turbine power generation is also increasing. Therefore, problems may occur that require urgent repair while the gas turbine rotor is stopped. When the gas turbine rotor turning is stopped and then restarted, if the turning period is not appropriate, severe vibration may occur due to rotor bending. As a result of the experiment, it was confirmed that normal operation is possible when the gap data measured at the start of rotor turning after maintenance work is similar to the existing value. And the vibration value at the start of rotor turning was lower as the rotor temperature was lower or the stop period was shorter.