• Journal of Applied Biological Chemistry
• /
• 제57권4호
• /
• pp.301-305
• /
• 2014

On-line screening high performance liquid chromatography (HPLC)-$ABTS^+$ assay를 이용한 청호로부터 chlorogenic acid, caffeic acid, vitexin, queretin, aremisinin의 항산화 활성을 온라인스크리닝 하였다. 이때 침적방법을 적용한 추출시간과 추출용매 조성으로부터 추출효율을 확인하였다. 이 결과 100% 물 추출물에서 수율이 가장 좋왔고 chloroenic acid의 항산화 활성이 가장 높았다. 또한 on-line screening HPLC-$ABTS^+$ assay 분석은 천연물에서 항산화 활성을 신속하게 탐색하는데 효율적이다.

• 한국생산제조학회지
• /
• 제7권1호
• /
• pp.51-57
• /
• 1998

In order to minimize vibration problems of rotating machinery rotors have been assembled through balancing machines. Since perfect balancing is impossible, residual unbalances cause serious vibration while the rotor is in high speed region. To minimize unbalance effects of magnetic bearing systems (AMB) during rotation on-line balancing methodology was studied. Unbalances were considered as disturbances of the system. The disturbance observer was used to estimate unbalance force from measurable state and input variables. Balancing inputs computed according to LQR and outputs of the observer were applied to eliminate unbalances during high speed rotation of the AMB. the effectiveness of the on-line balancing was verified through numerical simulations.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
• /
• pp.3052-3058
• /
• 2011

A high-speed train is the system that the electric power is supplied through the overhead contact line and drives motors. In this case that the de-wiring beteen the overhead contact line and the pantograph of a high-speed train, the occasion that smooth power supply is not accomplished occurs sometimes. If the de-wiring occurs, the arc discharge may damage the overhead contact line or the pantograph, and the falling-off in power quality may cause the damage and malfunctioning of motor block. This paper presents the methodology that the arc discharge by de-wring between overhead line and pantograph is discriminated through measuring the PT and CT in the vehicle, and measures the current collection characteristics for a high speed train.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
• /
• pp.22-24
• /
• 2004

This paper proposes a printing quality inspection system of film-type envelopment. Since the printing system is running at very high-speed (140m/min.) and the line error has very narrow width, we have to choose one-dimensional high-speed and high-resolution line scan camera. The vibration of the printing machine and the illumination environment make the inspection problem more harder. To obtain reliable inspection results, many software image processing techniques are applied and many parameters are tuned. The performance of the proposed system is proved by many simulations and long time real-plant experiments.

• 전기학회논문지
• /
• 제65권9호
• /
• pp.1605-1609
• /
• 2016

The measurement of current collection performance between pantograph and contact wire of overhead catenary system is intended to prove the safety of operation and the quality of the current collection system. The results of interaction performance of current collection system are required for approving with commercial operation on railway lines. The methods of interaction performance of current collection system are defined on interactional standards such as IEC 62486 and EN 50317. In this paper, the interaction performance is evaluated by the percentage of arcing on Honam high-speed line and the results are used for adjustment of the overhead catenary line structure. The experimental results in Honam high-speed line confirm that the duration of an arc lasting longer 25 ms between pantograph and contact wire was depended on the conditions of overhead contact line after installation.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2004년도 춘계학술대회 논문집
• /
• pp.192-198
• /
• 2004

KTX is the high speed train which is designed for 300km/h in maximum operation speed. But its long train set may cause unstable characters as swaying of the tail of a train and when the train is running on conventional line not on the high speed line, its funning safety is a point to be considered cautiously. In this study, we evaluated the running safety by the numerical analysis using VAMPIRE and compared the result with the test result of KHST, which is being in performance tests, for verifying the validity of analysis results.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2002년도 하계학술대회 논문집 A
• /
• pp.115-117
• /
• 2002

In general, it is supposed that load characteristics of high and low voltage distribution line are always coincidence. But in practical distribution system, voltage variation characteristics of high and low voltage distribution line are not same. Then in this paper, we proposes a voltage regulation method considering load variation characteristics of high and low voltage distribution line in distribution system.

• 센서학회지
• /
• 제14권6호
• /
• pp.438-443
• /
• 2005

In this paper, we introduce the on-line test of the current collection characteristics for HSR 350x(Korea High Speed Train project) that have been performed in the Kyoung-bu high-speed line since 2002. Through the analysis of measured data during on-line test, the variation trends of contact force between pantograph and catenary according to the track conditions and driving patterns are reviewed. This study shows that the track conditions do not affect on the dynamic performance between pantograph and the driving patterns are important factors in determining the good interaction of them.

• International Journal of Railway
• /
• 제6권2호
• /
• pp.64-68
• /
• 2013

In recent years, the speed of a train has been recognized as one of the important factors to determine the competitiveness as a mean of transportation. In line with this, infrastructure improvements and enhancements are being made with increases in the speed of train. Accordingly, there is a need to establish plans for infrastructure improvements through a comprehensive analysis of signals, track/civil engineering, catenary and environment, etc. to improve the speed of a train of high-speed train service sections in Korea. This study proposes improvement plans for catenary systems by investigating the possibility of improvements through performance analysis of catenary equipment by speed increase based on the analysis on catenary systems in Gyeongbu high-speed line, and analysis the applicability of catenary improvements and economic feasibility.

• 조명전기설비학회논문지
• /
• 제27권5호
• /
• pp.61-66
• /
• 2013

In this paper, a control scheme with the capability of high efficiency, which is realized by predicting the conditions of a load power and an input power, is proposed for the uninterruptible power supply (UPS). Generally, on-line UPS system supplies a constant voltage and a constant frequency (CVCF). However, the efficiency of the On-line UPS system can be reduced due to the switching losses of semiconductor devices during the power conversion. The these losses are improved by the proposed smart UPS with the high efficiency drive system, which is realized by analysing and predicting the conditions of a load power and an input power.