• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 춘계학술대회논문집
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• pp.892-896
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• 2001

백색잡음 불규칙 과정으로 모델링된 난류형태의 유체운동에 의하여 가진되는 비선형 시스템의 특성과 제어기법에 대해 연구하였다. 고려된 물리적인 모델은 주질량과 끝단 집중질량을 갖는 보형태의 구조물이다. 그 지배방정식은 확률론적 관점에서 F-P-K 접근법으로 유도되었고, 비선형 해석법으로 Gaussian Closure방법을 이용하였다. 비선형 시스템의 제어기법으로는 슬라이딩 모드 제어기를 최초로 확률영역에서 설계하고 그 효과를 확률영역 및 시간영역에서 고찰하였다.

• 한국식품영양학회지
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• 제20권4호
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• pp.369-377
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• 2007

An investigation evaluating the preparation and physicochemical properties of sauce with various herbs(sancho, sage, and rosemary) derived from soy sauce was performed. The effects of the different kinds of herbs added to sauce for roasted mackerel were assessed using physiochemical, sensory, flavor, and texture analysis properties. This fish was then compared to, fish with salt. The moisture, crude protein, crude fat, and crude ash content of the roasted mackerel were significantly higher than the control(p<0.05, p<0.001). The salinity content of the herb sauce added samples were significantly higher than the control(p<0.05). Conversely, the pH and peroxide value of the herb sauce added samples were significantly lower than the control(p<0.001). A positive trend was observed for color value with sancho added sauce(p<0.001). The another positive effects on the texture of fish was observed for texture analysis, adhesiveness, springiness, gumminess, and chewiness with herb sauce added samples(p<0.05). In the flavor profile, the fishy smell was disappeared and antifungal flavor was improved with herb added sauce. Flavor, taste, texture, and overall preference of herb sauce were significantly highest in sancho added sauce(p<0.05, p<0.001). Results suggest that the best herb sauce for roasted mackerel was sancho added sauce.

• Journal of Power Electronics
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• 제17권5호
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• pp.1268-1277
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• 2017

Three-phase pulse width modulation (PWM) rectifiers are usually designed under the assumption of ideal ac power supply and input inductance. However, non-ideal circuit parameters may lead to a voltage collapse of PWM rectifiers. This paper investigates the mechanism of voltage collapse in three-phase PWM rectifiers. An analytical stability boundary expression is derived by analyzing the equilibrium point of the averaging state space model, which can not only accurately locate the voltage collapse boundary in the circuit parameter domain, but also reveal the essential characteristic of the voltage collapse. Results are obtained and compared with those of the trial-error method and the Jacobian method. Based on the analysis results, the system parameters can be divided into two categories. One of these categories affects the critical point, and other affects only the instability process. Furthermore, an effective control strategy is proposed to prevent a vulnerable system from being driven into the instability region. The analysis results are verified by the experiments.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.271-272
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• 2006

This paper presented a new experimental gain tuning technique for a Multi-Axis Servo System. First, the investigation for proportional gain of velocity control loop by using a Dynamic Signal Analyzer (DSA) was performed. Using the FUNCTION characteristic of DSA based on the Bode plot, the Bode plot of open loop transfer function was obtained. In turn, the integral gain of a servo controller can be found out by using the Integration time constant extracted from the Bode plot of open loop transfer function. In the meanwhile, the positional gain of the servo controller has been obtained by using the Bode plot of the closed loop transfer function. We have also proposed the technique to find out an optimal parameter of a notch filter, which has a great influence on vibration reduction, by using the damping factor extracted from the Bode plot of closed loop transfer function.

• Journal of Advanced Marine Engineering and Technology
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• 제19권3호
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• pp.99-106
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• 1995

PWM(Pluse Width Modulation) induction motor drives are being used in greater numvers through a wide variety of industrial and commercial applications. In this paper, a new speed control algorithm (hybrid algorithm) for induction motor drives that uses regular sampled PWM and harmonic elimination PWM is presented. The hybrid algorithm in implemeted on the computer to obtain solutions from the calculation equations of the width of the pulses and the firing angles for the selected harmonic elimination. this paper describes the time delay effects and the suitable compensating methods moreover, optical transmission system for driving signals is proposed and is compared with general trnasmission system. The hybrid inverter was tested with induction motor, and these test results are shown that this hybrid inverter closely approximates and exhibits many of the desirable performance characteristic distortions and eliminated the objectionable harmonics. Finally, detailed experimental investigation of the proposed hybrid scheme in presented.

• Journal of Acupuncture Research
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• 제20권2호
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• pp.1-10
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• 2003

Objective : It is limited to verify existence and a part of characteristic of MS(Meridian system) in modern MS hypothesis. Because it is that an object of scientific approach is to prove a structure of MS. Then according to DMMS, we will research on a subject of MSs rules. This is a paper on the investigation of DMMS in aspects of propriety and supplement. Results : DMMS is composed of organizational anatomy system, MS, signal system. This means that the contents of classic MS theory divide into three dimensions. It includes classic MS theory and explains modern MS hypothesis with DMMS. But is has two problems that one is the difference between the right side and the left in the same meridian and the other is a lack of dynamic idea(動態觀念). After apply this ti analysis system, it will be reasonable to DMMS. It indicates to use various ways of a science, especially, mathematics, system theory, information theory, control theory to supplement the DMMS. Conclusions : Although the scientific study of MS is stagnant, the approach of this DMMS will provide us with a new result of MS.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.670-677
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• 2003

Although Gas Tungsten Arc Welding (GTAW or TIG welding) is considered as high quality and precision welding process, it also has demerit of low melting rate. Narrow-gap TIG welding which has narrow joint width reduces the groove volume remarkably, so it could be shorten the welding time and decrease the overall shrinkage in heavy wall pipe welding. Generally Narrow-gap TIG welding is used as orbital welding process, it is important to select the optimum conditions for the automatic control welding This paper looks at the application and metallurgical properties on Narrow-gap TIG welding joint of heavy wall large austenitic stainless steel pipe to determine the deposition efficiency, the resultant shrinkage and fracture toughness. The fracture toughness depends slightly on the welding heat input.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 1997년도 춘계학술대회논문집; 경주코오롱호텔; 22-23 May 1997
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• pp.55-59
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• 1997

Investigation is performed on the stability of general form of dynamic system whose damping and stiffness are varying in irregular manner along time, which is a preliminary result in the course of research on the characteristic and the control of the stochastic system. The governing equation of the 'parametric' system is derived via F-P-K approach in stochastic sense. The influence on the stability due to the magnitude of auto power spectral density and cross power spectral density of random variation of system parameters is studied and the region is surveyed.

• 센서학회지
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• 제15권6호
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• pp.449-456
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• 2006

The purpose of urodynamic investigation is to obtain the information on the function of the urinary system. The aim of this study is to acquire the useful information of lower urinary tract symptom (LUTS) diagnosis through void force signal as noninvasive method. The system which could evaluate the function of compensatory hypertrophy with noninvasive and comfortable method was implemented to measure uroflow and void force during urination. The implemented system composes of the sensor parts, signal conditioning parts and PC monitoring program. For the evaluation of the implemented system, the simulation of control part of the system was performed and the model system for the lower urinary system was designed. The superiority of a measuring characteristic of the implemented system was verified using the model system. From the evaluation of the model system, we have found out that the void force was dependent on the occlusion degree and compensatory hypertrophy significantly.

• 한국군사과학기술학회지
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• 제17권2호
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• pp.258-264
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• 2014

In terms of chemical detection performance related with chemical material sampling, this investigation shows optimized values, resulted from minimizing loss from air turbulence and other reasons when pressure changes on the basis of sampling flow rate Based on simulations and pressure control of the outside conditions it became possible to obtain ion mobility detection optimum values, and to derive standard pressure conditions that is appropriate for DMS characteristic.