• Title/Summary/Keyword: 김기웅

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양자 상태 수 변화에 따른 양자 암호키 분배 보안성 분석

  • Go, Hae-Sin;Im, Gyeong-Cheon;Kim, Gi-Ung;Seo, Chang-Ho;Lee, Jun-Gu
    • Information and Communications Magazine
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    • v.31 no.9
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    • pp.70-76
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    • 2014
  • 절대 보안성을 제공하는 양자 키 분배 (quantum key distribution, QKD)는 양자 역학을 이용한 정보통신 응용 중 가장 현실적으로 유망한 분야이다. BB84는 가장 널리 알려진 양자 암호키 분배 프로토콜로써, 4개의 양자 상태를 사용한다. 그 이후, 6개의 양자 상태를 사용하는 six-state 프로토콜이 제안되었으며, 이는 기 제안된 BB84프로토콜 대비 더 높은 보안성을 보이는 것으로 알려져 있다. 또한 QKD의 암호키 전송률 및 보안성 증가를 위해 이중 큐빗 QKD 프로토콜이 제안되었다. 이중 큐빗은 하나의 광자에 편광, 위상, 그리고 주파수 등의 서로 다른 두 개의 변조를 하는 것이다. 이중 큐빗 QKD 프로토콜은 16개의 양자 상태를 사용하며, 심볼 오류율 (Symbol Error Rate, SER)관점에서 앞서 언급한 두 개의 프로토콜 보다 더 높은 보안성을 보장할 수 있다. 본고에서는 앞서 언급한 총 3종류의 QKD 프로토콜의 보안성을 분석하고 비교함으로써 양자 상태 증가에 따른 QKD보안성을 성능을 살펴본다.

Evaluation of network protocols for automotive data communication (차량용 데이터 통신을 위한 네트워크 프로토콜의 평가)

  • Yun, Jung-A;Nam, Sang-Woon;Kim, Kee-Woong;Lee, Suk
    • Journal of Institute of Control, Robotics and Systems
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    • v.3 no.6
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    • pp.632-638
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    • 1997
  • The growing number of electronic components used in automobiles has given rise to problems concerning the increasing number, size and weight of the wiring harnesses. As an approach to resolve these problems, multiplexed wiring systems using automotive communication protocol such as Controller Area Network(CAN), Advanced PALMNET and J1850 have been developed by many automobile companies. In order to compare these protocols quantitatively, this paper presents the performance evaluation of CAN and Advanced PALMNET via discrete event simulation. Through numerous simulation experiments, several important quantitative performance factors such as the probability of a transmission failure, average system delay(data latency), and throughput have been evaluated.

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A study on the diversification in revenue sources for Incheon International Airport Based on other airports in the foreign countries (인천국제공항의 수익원 다양화 방안에 관한 연구 - 해외 공항의 사례를 바탕으로 -)

  • Kwon, Tae-Hoon;Kim, Kee-Woong
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.17 no.4
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    • pp.63-69
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    • 2009
  • Incheon International Airport as the gateway to Korea is having the happiest time with those honorable prizes. But in these days, the trend of aviation is changing rapidly, so many rival airports in the world as well as north-east asian countries are rushing to find new revenue sources not to be turned over. Hence Incheon International Airport should push into fresh fields or create new sources of business keeping innovation by making foreign airports its role model. This study brings up some new profit models of foreign airports; Malaysia's Kuala Lumpur International Airport, China's Xiamen Aviation Industry Zone, German's Frankfurt Fraport Airports Group. This study analyzes the status of listed airports and presents strategies after investigating whether they are suitable for and compatible to Incheon International Airport.

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Combinatory Effects of Benzene, Toluene and Xylene on the Induction of Rat Liver Microsomal Enzymes and Their Metabolites (흰쥐 간의 microsomal enzymes의 유도에 있어서 benzene, toluene과 xylene의 복합적인 영향과 그들의 대사산물)

  • 김기웅;박상신;김태균;문영한;장성근
    • Toxicological Research
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    • v.12 no.1
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    • pp.9-15
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    • 1996
  • We studied the effects of a single, combined and mixed exposure of benzene, toluene and xylene on the activities of rat liver microsomal AHH, ADH and ALDH, and the excretion of their metabolites in urine. The AHH activities of the rats treated in combination and mixture were slightly higher and/or similar to those rats treated with single solvent, while the reverse effects were observed for ADH and ALDH. Similar effects were observed when the metabolites were examined in urine (p < 0.01). These results suggest that each solvent might interJkre the induction and action of ADH and ALDH, and decrease the excretion of their metabolites into urine.

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Isolated PFC using HMF for EV Fast Charger (전기자동차 급속충전기를 위한 HMF기법 절연형 PFC)

  • Lee, Byung Kwon;Kim, Gi Woong;Kim, Young Se;Choi, Kyeong Min;Lee, Jun Young
    • Proceedings of the KIPE Conference
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    • 2019.07a
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    • pp.295-296
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    • 2019
  • 본 논문은 넓은 출력전압 범위와 High Power Density를 위한 절연형 HMF PFC(Isolated Harmonic Modulation PFC)를 제안한다. 제안된 PFC는 변압기 leakage inductance를 회로에 적용시켜 switching device의 voltage stress를 효과적으로 줄일 수 있는 voltage-fed형태의 ful-bridge구조를 기반으로 한다. 출력 측 CV(Constant Voltage) control을 통하여 출력 혹은 link 전압을 load 변동에 상관없이 일정 유지시켜준다. 또한 CC(Constant Current) control 방식을 사용하여 출력 측 battery 특성 조건이 변동되어도 일정하게 충전시켜 줄 수 있도록 한다. HMF 제어방식을 적용한 3.3kW Prototype을 통해 이를 입증한다.

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Study on the Fabrication and Characterization of Hydrophobic Surface with Hierarchical Microstructure using Spray Coating Deposition Method (스프레이 코팅 증착 방식을 이용한 계층적 미세 구조의 발수표면 제작 및 특성 분석에 대한 연구)

  • Jongyun Choi;Kiwoong Kim
    • Journal of the Korean Society of Visualization
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    • v.21 no.3
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    • pp.15-22
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    • 2023
  • This research introduces an innovative approach for fabricating microstructure surfaces using spray-coating deposition. The resulting surface, referred to as Magnetically Responsive Microstructures (MRM), exhibits hierarchically structured micro-pillar arrays with remarkably high aspect ratios. The fabrication process involves precisely mixing PDMS and hexane with Carbonyl iron powders, followed by ultrasonication and spray-coating on the top of a PDMS substrate placed on the neodymium magnet. The MRM surface shows hydrophobic properties, characterized by a contact angle surpassing 150° and an aspect ratio exceeding 10. Through a comprehensive exploration of critical parameters, including spray amount, magnet-substrate distance, and solution ratio enhanced dynamic tunability and exceptional hydrophobic characteristics are attained. This novel approach holds significant potential for diverse applications in the realm of dynamically tunable microstructures and magnetically responsive surfaces.

Study on the Image-Based Concrete Detection Model (이미지 기반 콘크리트 균열 탐지 검출 모델에 관한 연구)

  • Kim, Ki-Woong;Yoo, Moo-Young
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2023.11a
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    • pp.97-98
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    • 2023
  • Recently, the use of digital technology in architectural technology is gradually increasing with the development of various industrial technologies. There are artificial intelligence and drones in the field of architecture, and among them, deep learning technology has been introduced to conduct research in areas such as precise inspection of buildings, and it is expressed in a highly reliable way. When a building is deteriorated, various defects such as cracks in the surface and subsidence of the structure may occur. Since these cracks can represent serious structural damage in the future, the detection of cracks was conducted using artificial intelligence that can detect and identify surface defects by detecting cracks and aging of buildings.

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Circadian Rhythms of Plasma MHPG and HVA Concentrations in Healthy Young Adults (혈장(血漿) MHPG와 HVA 농도(濃度)의 24시간(時間) 주기성(週期性) 변화(變化)에 관한 연구(硏究))

  • Kim, Ki-Woong;Lee, Jung Hie;Woo, Jong Inn
    • Korean Journal of Biological Psychiatry
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    • v.2 no.2
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    • pp.266-274
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    • 1995
  • We invesigated whether the circadian rhythms of plasma MHPG and HVA concentrations exist in 11 healthy young adults, and analyzed the patterns of their circadian rhythms. The results were as follows : 1) The change in the mean plasma MHPG concentrations analyzed by repeated measures ANOVA was not statistically significant. Five subjects showed significant circadian rhythms of plasma MHPG concentrations of each individual, and 4 of those had the acrophases between 17PM and 24PM. 2) The change in the mean plasma HVA concentrations analyzed by repeated measures ANOVA was not statistically significant. Six subjects showed significant circadian rhythms of plasma HVA concentrations of each individual, and 4 of those had the acrophases between 21PM and 6AM. In conclusion, the circadian rhythm pattern of plasma HVA concentrations in our result is consistent with the previous study. It was suggested that plasma MHPG and HVA concentrations should be measured more frequently, and the physical activities of subjects be controlled more strictly for the following study.

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A Study on Balanced Airport Slot Allocation Model Applying AIP Model -Focused on Incheon International Airport- (AIP 모델을 응용한 균형적 공항 슬롯 배정 모델에 관한 연구 -인천국제공항 사례 연구-)

  • Park, Hak-Soon;Kim, Kee-Woong
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.26 no.1
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    • pp.25-36
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    • 2018
  • This paper presents a new airport slot allocation model that uses AIP model to balance the use of airport slots within existing capacity based on the limitation of capacity expansion of airport slots. This new model is called a 'balanced airport slot allocation model', which integrates the airport facility usage system, which is applied independently without linkage, with the airport slot allocation system, introducing the market logical characteristic of 'administered incentive pricing. In this paper, we propose a new proposal to dramatically change the airport slot allocation system in the current situation where the expansion of facilities is limited in the urgent problem of the airport slot shortage, and it is necessary to balance the airport slot allocation. Airline paying for the use of an airport slot can determine the slot of the desired time slot based on the costs incurred by differentiating in the new airport slot allocation model. This is a system that allows the airlines that are willing to pay a lot of money in the market to use preferred airport slots.

A Study on the Effect of Airline Pilot's Organizational Identification, Emotional Exhaustion and Perceived Justice on Tunrover Intention and Negative Word-of-Mouth (소속감과 정서적 고갈 그리고 지각된 정의가 이직의도와 조직에 대한 부정적 구전에 미치는 영향 - 파업 후 복귀한 A항공사 운항승무원을 대상으로 -)

  • Kim, Y.S.;Park, S.B.;Kim, K.W.;Oh, B.C.;Hossan, M.A.
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.16 no.3
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    • pp.38-49
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    • 2008
  • Recently industries have started to recognize the importance of word-of-mouth marketing and human resource management especially for airline industries who suffer from pilot shortage. Pilots are very important component of airline company and require a lot of money and time to assession, training and maintaining certified license validity. This study is to test the effect of airline pilot's organizational identification, emotional exhaustion and perceived justice on turnover intention and negative word-of-mouth on airline union pilots returned from the strike. This study used both literary method and empirical method. The researcher did literary study based on the previous study, designed the research model and hypothesis, did questionnaire survey to the Union member pilot from year 2005 strike for the subject of study to verify hypothesis and analysed empirically the finding using SPSS12.0 program. The major findings of this study may be summarized as follows, (1) organizational identification has a negative effect on turnover intention and negative word-of-mouth, (2) emotional exhaustion has a positive effect on turnover intention and negative word-of-mouth, (3) perceived justice has a negative effect on turnover intention and negative word-of-mouth.

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