• 한국주거학회:학술대회논문집
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• 한국주거학회 2002년도 추계학술발표대회
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• pp.321-326
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• 2002

To design mechanical ventilation for bathroom of apartment houses where air supply and exhaust are taken Into consideration, mock-ups of ventilation systems, widely used in bathroom of apartment houses with an area of 100$m^2$, were made and installed in a laboratory, These ventilation mock-ups were available for control of air supply and exhaust, and the size of supply openings were 40cm$\times$1cm, 40cm$\times$3cm, 40cm$\times$5cm. They were installed at five positions, spaced 40cm at a height of 25cm from the floor. and the position of exhaust fans were four corners and center Exhaust fan established each one on corner of the ceiling and one in center. As result that measure ventilation effect by each condition, size of hole that supply air is big, and ventilation effect took effect to be good establishment location is low, Also, distance of exhaust fan is far with hole that supply air, ventilation effect took effect by superior thing.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 추계학술대회 논문집 학회본부
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• pp.159-161
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• 1994

A new control technique which generates high-quality sinusoidal output voltage from a single-phase resonant do link inverter suitable for the UPS systems is presented. The inverter output voltage control system has the PID controller with a minor loop of the filter inductor current and tile feedforward controller. The proposed control scheme also solves resonant voltage overshoot without any additional switch or passive component, resulting in pulses with uniform amplitude and high efficiency. Experimental results in the case of linear and nonlinear loads are presented to confirm the usefulness of the Proposed control algorithms.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 F
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• pp.2013-2015
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• 1997

Elevator stops emergently when power failures happen during operation. In that case, the passenger should wait with frightened in the car untill they are rescued by repair man or power resumes. This paper describes an automatic landing device for power-failure(ALP) that consists of UPS and battery charge control system. The excellence of the ALP operation is verified by experiments in elevator test tower.

• 벤처창업연구
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• 제19권1호
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• pp.119-133
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• 2024

정부가 공공기술 사업화와 벤처창업 생태계 활성화를 위해 대규모 투자를 한 결과, 지난 2006년부터 1,600호 이상의 연구소기업이 등록, 21년 기준 1.1조원 규모의 매출이 발생하는 등의 양적 성과가 있었다. 그러나 이 성과는 연구소기업 1개당 평균 매출액 등이 지속하락하는 등 질적측면에서 문제가 발생하였으며 이 원인 진단으로 경영자의 기술지향성과 시장지향성 여부에 주목하게 되었다. 본 연구는 연구소 기업의 기술지향성과 시장지향성이 경영성과에 미치는 영향과의 관계에서 마케팅 비용과 연구개발 비용의 조절 효과가 어떠한 영향을 미치는지 분석하여 기업생존율 향상을 도모함으로써 연구소기업의 질적성장 개선에 시사점을 제시하는 것을 목적으로 하였다. 본 연구는 선행연구와 실증분석을 통해 크게 3가지 연구결과를 도출하였다. 첫째, 기술지향성의 기술우수성, 기술혁신성은 경영성과에 유의한 영향을 미쳤으나 기술집약도는 유의한 영향을 미치지 않은 것으로 확인되었다. 둘째, 시장지향성의 고객지향성, 경쟁지향성은 경영성과에 유의한 영향을 미쳤으나, 진입장벽 단일 항목으로는 경영성과에 유의한 영향을 미치지 않았다. 셋째, 일반현황을 통해 확보한 마케팅 비용과 연구개발 비용을 조절변수로 투입한 결과 다른 변수에는 영향을 미치지 않았으나 유일하게 진입장벽과 상호작용하여 재무적 경영성과에 영향을 미쳤으며, 연구개발비용은 음(-)의 완충효과를, 마케팅비용은 양(+)의 강화효과를 미치는 것으로 확인되었다. 이를 통해, 본 연구는 기술지향성과 시장지향성 모두 연구소기업 경영성과에 직접적 영향을 미치며, 연구소기업 성장에 영향을 미치는 중요 요인임을 확인하였다. 또한, 기업의 마케팅 및 연구개발 투자가 연구소기업의 초기 진입장벽 해소와 재무적 성과 향상에 유의한 영향을 미치는 요인임을 확인하였다. 이에 연구소기업 특성을 고려한 기술지향성과 시장지향성 강화에 대한 필요성을 시사하였으며, 다섯가지 이론적 기여점을 제시하였다. 첫째, 연구소기업의 기술사업화 및 기술혁신을 위한 제도적 지원체계를 강화할 필요가 있다. 둘째, 연구소기업 선정을 위한 검토위원회에서 기술성 외에 시장성 등을 질적 평가할 수 있도록 지표 등 개선이 필요하다. 셋째, 연구소기업 발굴 시점에서부터 투자 관점에서 기술성과 시장성을 고루 분석하고 판단하여 발굴할 필요가 있다. 넷째, 연구소기업의 원활한 초기시장 진입을 위해 마케팅 교육이나 컨설팅 등의 지원 강화가 필요하다. 다섯째, 각 연구소기업의 산업적 특성을 효율적인 연구개발 및 마케팅비용 투자를 할 수 있도록 지출전략과 마일스톤 수립 등을 지원할 필요가 있다.

• Journal of Electrical Engineering and Technology
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• 제8권4호
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• pp.704-711
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• 2013

Data center is an information hub and resource for information-centric society. Since data center houses hundreds to ten thousands servers, networking and communication equipment, and supporting systems energy saving is one of the hottest issues for green data center. Among several solutions for green data center this paper introduces higher voltage direct current (DC) power feeding system. Contrary to legacy alternating current (AC) power feeding system equipped with Uninterruptible Power Supply (UPS), higher voltage DC power feeding system is reported to be a more energy efficient and reliable solution for green data center thanks to less AC/DC and DC/AC conversions. Main focus of this paper is on reliability issue for reliable and continuous operation of higher voltage DC power feeding system. We present different types of configuration of the power feeding systems according to the level of reliability. We analyze the reliability of the power feeding systems based on M/M/1/N+1/N+1 queueing model. Operation of the power feeding system in case of failure is also presented.

• BMB Reports
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• 제54권12호
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• pp.592-600
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• 2021

Parkinson's disease (PD) is one of the most common neurodegenerative diseases in the elderly population and is caused by the loss of dopaminergic neurons. PD has been predominantly attributed to mitochondrial dysfunction. The structural alteration of α-synuclein triggers toxic oligomer formation in the neurons, which greatly contributes to PD. In this article, we discuss the role of several familial PD-related proteins, such as α-synuclein, DJ-1, LRRK2, PINK1, and parkin in mitophagy, which entails a selective degradation of mitochondria via autophagy. Defective changes in mitochondrial dynamics and their biochemical and functional interaction induce the formation of toxic α-synuclein-containing protein aggregates in PD. In addition, these gene products play an essential role in ubiquitin proteasome system (UPS)-mediated proteolysis as well as mitophagy. Interestingly, a few deubiquitinating enzymes (DUBs) additionally modulate these two pathways negatively or positively. Based on these findings, we summarize the close relationship between several DUBs and the precise modulation of mitophagy. For example, the USP8, USP10, and USP15, among many DUBs are reported to specifically regulate the K48- or K63-linked de-ubiquitination reactions of several target proteins associated with the mitophagic process, in turn upregulating the mitophagy and protecting neuronal cells from α-synuclein-derived toxicity. In contrast, USP30 inhibits mitophagy by opposing parkin-mediated ubiquitination of target proteins. Furthermore, the association between these changes and PD pathogenesis will be discussed. Taken together, although the functional roles of several PD-related genes have yet to be fully understood, they are substantially associated with mitochondrial quality control as well as UPS. Therefore, a better understanding of their relationship provides valuable therapeutic clues for appropriate management strategies.

• 전기학회논문지P
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• 제59권2호
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• pp.158-162
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• 2010

PSD is automatically opened and closed when subway train arrive on the station. This system was designed to control electric automatic system. These doors will provide passenger safety, energy saving and a good environment in subway. The monitoring and control systems of PSD are configured so that they can be operated in automatic mode in connection with ATO through the composite control panel in the station control room. The objective of this paper is to obtain high reliability that is essential for monitoring and control systems of PSD. The power supply is based on protection circuit using DC power bridge from two UPS. Also, stable communication system consists of CAN communication line redundancy and RF cross protection algorithm. Monitoring state display results show the validity of the proposed high reliability monitoring and control systems of PSD.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 학술대회 논문집 전문대학교육위원
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• pp.110-112
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• 2003

Harmonics happened due to nonlinear systems such as UPS, SCR controlled motors, and fluorescent lighting in distribute power system is very important subject to optimal operate and control of power system. Harmonics sometimes takes place incorrect operation of protective relaying system under normal condition on power system. This paper presents the actual recording data of transformer located at substation of industrial installation for harmonic analysis in detail.

• Ocean Systems Engineering
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• 제4권3호
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• pp.201-213
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• 2014

Wave run-up is an important issue in offshore engineering, which is tightly related to the loads on the marine structures. In this study, a series of physical experiments have been performed to investigate the wave run-up around a vertical cylinder in transitional water depth. The wave run-ups of regular waves, irregular waves and focused waves have been presented and the characteristics in frequency domain have been investigated with the FFT and wavelet transform methods. This study focuses on the nonlinear features of the wave run-up and the interaction between the wave run-up and the cylinder. The results show that the nonlinear interaction between the waves and the structures might result wave run-up components of higher frequencies. The wave run-ups of the moderate irregular waves exhibit 2nd order nonlinear characteristics. For the focused waves, the incident waves are of strong nonlinearity and the wavelet coherence analysis reveals that the wave run-up at focal moment contains combined contributions from almost all the frequency components of the focused wave sequence and the contributions of frequency components up to 4th order harmonic levels are recommended to be included.

• Journal of Information Display
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• 제6권1호
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• pp.28-32
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• 2005

The electronic structures of Al/RbF/tris-(8-hydroxyquinoline)aluminium ($Alq_3$) and $Al/CaF_2/Alq_3$interfaces were investigated using x-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS). For both systems, the UPS showed a significant valence band shift following the deposition of the thin fluoride layers on $Alq_3$. However, the formation of gap state in valence region and the extra peak N 1s core level spectra showed different trends, suggesting that the alkali fluoride and alkali-earth fluoride interlayer have different reaction mechanisms at the interface between Al cathode and $Alq_3$. In addition, the deposition of Al has considerably less effect on the valence band shift compared to the deposition of both RbF and $CaF_2$. These results suggest that the charge transfer across the interface and the resulting gap state formation may have lesser effect on the enhancement of organic light-emitting device performance than the observed valence band shift, which is thought to lower the electron injection barrier.