• 한국군사과학기술학회지
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• 제8권3호
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• pp.11-17
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• 2005

In this paper, the mathematical model of the underwater discharge system using a linear pump is derived and the suitable opening pattern of a flow control valve which satisfies the discharge performance requirements is obtained through the underwater discharge simulations. The simulation results show that the dynamic characteristics of a projectile are greatly affected by the opening pattern of the flow control valve, however, hardly by the diving depth. It is anticipated that the simulation model can be used to derive the design parameters and analyze the performance of the designed underwater discharge system using a linear pump.

• Journal of Electrical Engineering and Technology
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• 제6권1호
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• pp.123-127
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• 2011

To clarify the relations of optical properties to the main factors responsible for the loss and damage of luminous efficacy, a 20 min turn-on/turn-off test for 2,000 h for a ceramic metal halide lamp is conducted. The corrosion rates of the arc tube wall and electrode are estimated based on thermal stress. Wall blackening is attributed to the tungsten being transported from the hot electrode tips to the relatively cold arc tube wall. Furthermore, the grain boundaries of the arc tube are changed by the degradation. Distortion of the electrode is observed, and the ignition and the driving voltage of the load both increase. Finally, the color rendering index and the color coordinates are changed after the degradation. The luminous flux and the intensity of the luminous distribution are decreased significantly.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.371-372
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• 2008

In this paper, we experimentally investigated discharge phenomena inside vacuum interrupter at 1 to 20 Torr to simulate the vacuum leakage. We used glass type of vacuum interrupter where the internal pressure and the type of gasses can be varied according to requirement. The experiment is conducted under ac applied voltage and the experimental circuit is constructed to simulate the actual circuit used in cubical type insulated switchgear. We used two types of gases such as air and $SF_6$. The use of glass type vacuum interrupter allowed us to measure discharges occurring in vacuum interrupter optically. We measured and discussed the discharge occurring in both gases with a current transformer and ICCD camera. We also revealed that electromagnetic wave spectra emitted by the discharge have same frequency range for both gasses.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2001년도 Proceedings ICPE 01 2001 International Conference on Power Electronics
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• pp.261-265
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• 2001

In this paper, a current-source type parallel indudor compensated load resonant high-frequency soft switching inverter using IGBTs for driving the newly-produced silent discharge type ozone generating tube and excimer lamp for UV generation which incorporate a single switched capacitor resonant snubber between the port in DC busline side is presented, together with its pulse modulated unique output power regulation characteristics.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 추계학술대회논문집
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• pp.875-880
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• 2002

It is necessary to determine the vibration source and its transmission paths in order to develop a low-noise compressor. Through the use of multiple-input/single-output(MISO) mode1, the transmission paths of vibration within a reciprocating compressor have been investigated. In order to identify the transmission path, we measure the accelerations of the block and transverse vibrations of the line discharge tube. As outputs, vibrations of compressor shell were measured at three positions; cylinder head, one near the suction line, and the top of upper shell. The partial coherence function and transfer function are obtained ken the measured data, and the results are observed in order to determine vibration source and its influence on the shell vibration.

• Journal of the Optical Society of Korea
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• 제12권1호
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• pp.31-37
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• 2008

To increase output power of a He-Ne laser we propose to use the capacitive rf discharge and implement four channel structure. Most of experiments were carried out with a single laser tube from this structure to optimize the output mirror transmission, pressure and composition of the mixture. A laser tube of 2.8 mm inner diameter and 50 cm discharge length can give an output power of above 5.5 mW at 3.39 ${\mu}m$. Four such tubes in "matrix" structure let us obtain 20 mW of output. Simplified models which can be used to evaluate the behavior of an equivalent electrical circuit with laser plasma and qualitative characteristics of output power of He-Ne laser were also described.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 추계학술대회논문초록집
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• pp.386.1-386
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• 2002

It is necessary to determine the vibration source and its transmission paths in order to develop a low-noise compressor Through the use of multiple-input/single-output(MISO) model, the transmission paths of vibration within a reciprocating compressor have been investigated. In order to identify the transmission path, we measure the accelerations of the block and transverse vibrations of the line discharge tube. (omitted)

• Journal of Chest Surgery
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• 제33권10호
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• pp.812-816
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• 2000

Background ; To evaluate the efficacy of Fibrin glue to decrease recurrence in video-assisted thoracoscopic surgery(VATS) for a treatment of spontaneous penumothorax. Material and Method : All medical records of 17 patients who underwent a thoracoscopic wedge resections of bullae with stapling device with Fibrin glue in our institute between May 1998 and December 1999 were reviewed. variables analyzed include affected sites primary indication of VATS. duration from admission to discharge duration of postoperative stay duration of chest tube drainage recurrence and complication. There were 16 men and 1 woman. Result : There was no evidence of hemodynamic instability or arterial blood gas abnormalities encountered during the procedure. Mean age at the time of the VATS was 26.9 years (range 15 to 61 years) The mean duration from admission to discharge was 7.8 days and mean postoperative stay was 5.1days mean chest tube indwelling period was 4..0 days. There was no recurrence of pneumothorx. Conclusion : Thoracoscopic wedge resections with introduction of fibrin glue are safe and effective and requires only a short hospital stay. We believe that this thoracoscopic technique will further simplify the surgical treatment of pneumothorax.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 C
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• pp.1063-1065
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• 1999

Recently the ozone generation system is well used for cleaning the contaminated water by using the strong oxidization effects. Accordingly, with the purpose of improving ozone yield at the peak of ozone concentration, this paper describes the stracture and characteristics of ozonizer, and focused on the development of a 3E-3G discharge tube.

• 조명전기설비학회논문지
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• 제20권10호
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• pp.94-99
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• 2006

기존의 오존 발생 시스템과 차별화하기 위해 연속적으로 오존 농도 발생 특성을 분석하여 오존발생량을 실시간으로 제어가 가능하도록 하였다. 파이렉스 방전관의 수집부에서는 랩뷰 프로그램을 사용하여 방전관의 오존 농도 및 유량을 측정하여 저장한다. 그리고 조절부에서는 정리된 데이터를 이용해 오존 발생량을 조절한다. 따라서 오존 발생량을 환경에 따라 투입하여 에너지 효율을 증가시키고자 하였다.