폴리머 결합 링 반사기를 이용한 하이브리드 집적 파장 가변 레이저

박준오,이태형,정영철,Park, Joon-Oh,Lee, Tae-Hyung,Chung, Young-Chul 한국광학회 2008 한국광학회지 Vol.19 No.3

광대역 파장 가변 레이저를 구현하기 위하여, 폴리머 결합 링 반사기를 반사형 반도체 광증폭기와 하이브리드 집적하여 광대역 파장 가변 레이저를 구현하였다. 도파로 폭과 높이의 제작 오차로 인하여 방향성 결합기의 결합 비 조합이 설계 값에서 다소 벗어나더라도 단일 피크 조건이 유지되도록 설계함으로써, 제작 수율을 높이도록 하였다. 구현한 파장 가변 레이저는 파장 가변 범위가 35 nm, 부모드 억제 비가 30 dB 이상 보임을 확인하였다. To realize a widely tunable laser diode, a polymer coupled-ring reflector is hybrid- integrated with reflective semiconductor optical amplifier. Even though ring-ring and ring-bus coupling ratios are changed by fabrication errors in waveguide width and height, they remain very close to the single peak condition, ensuring high yield in fabrication. The tuning range is observed to be about 35 nm, maintaining the side mode suppression ratio of about 30 dB.

5G 이동통신 적합 IETF QUIC 프로토콜 보안고려사항 검증

박준오,김진영,양윤모,유승태,강현우,유일선 순천향대학교 부설 산업기술연구소 2020 순천향 산업기술연구소논문집 Vol.26 No.2

The study to deliver data faster and more safely from 5G Mobile Communication has been made. The current TCP communication has structural problems, so it‘s not suitable for ultra-speed, ultra-low latency, and hyper-connectivity. IETF has standardized QUIC to deliver faster and more safely, but further study on security is needed. It has verified the possibility of attacks by writing and experimenting attack scenario for the three items out of 11 security considerations presented by IETF QUIC Draft - Handshake Denial of Service Attack, Amplification Attack, Version Downgrade Attack.

Clinical characteristics and the role of molecular tests in NTM musculoskeletal infections

박준오,위유미 대한내과학회 2021 대한내과학회 추계학술대회 Vol.2021 No.1

소아에서 뇌수두증의 단락술 이후 발생한 석회화된 만성 경막하 혈종 - 증례보고 -

박준오,권택현,박윤관,정흥섭,이훈갑,서중근,Park, Juno,Kwon, Taek-Hyun,Park, Youn-Kwan,Chung, Hung-Seob,Lee, Hoon-Kap,Suh, Jung-Keun 대한신경외과학회 2000 Journal of Korean neurosurgical society Vol.29 No.7

Post-shunting subdural hemorrhages are usually small and self-limited, and they can be recognized on the routine post-operative CT examinations. However, delayed subdural bleeding may occur without any clinical symptoms or signs. Thus the hematoma remains undetected, and it can be increased in size and sometimes become calcified with time. We experienced a case of 15-year-old male with a large calcified subdural hematoma who had undergone shunt operation 10 years previously. With pertinent review of the literatures, we discuss the possible mechanism of calcification and the proper way of treatment in calcified chronic subdural hematoma.

비행체의 상대적 측위 추정을 위한 Epipolar Geometry 기반의 ROS 시스템

박준오,엄태욱,안효성 제어로봇시스템학회 2022 제어로봇시스템학회 국내학술대회 논문집 Vol.2022 No.6

성형결합기 및 광도파로열 격자 파장 필터 손실특성 개선

박준오,정영철,백수현,이형종 한국광학회 2002 한국광학회지 Vol.13 No.1

기존의 성형결합기는 광파가 자유전파영역에서 회절에 의해 전파되는 사실이 잘 알려져 있다. 본 논문에서는 손실을 줄이기 위하여 회절에 의한 광파의 전파가 아닌 W-테이퍼 도파로에 의한 광파의 전파를 하는 새로운 개념의 성형결합기를 제안하였고, 이를 광도파로열 격자 파장 필터에 적용시켜 여러 가지 특성을 조사하였다. 새로운 개념의 저 손실 성형결합기 및 이를 이용한 광도파로열 격자 파장 필터는 기존의 성혈결합기 및 광토파로열 격자 파장 필터와 같은 성능을 나타내면서도 손실이 작음을 확인하였다. In the conventional star coupler, a certain amount of loss should be expected because lateral diffraction is used for the power distribution. In this paper, we propose a new design of a low loss star coupler which employs UV-written tapered waveguides and an AWG based on the low loss star couplers, and investigate their various characteristics. The loss of the UV-written star coupler is lower than that of the conventional star coupler, and the AWG device based on the UV-written star couplers shows low loss characteristics.

20세기 커스텀주얼리의 형성과 전망에 대한 연구

박준오 사단법인 한국조형디자인협회 2009 조형디자인연구 Vol.12 No.1

Until the mid 1900’s, Costume Jewel교 was lead by Gabriel Coco Chanel or the same fashion designers like her in France. Chanel made a new vogue by a fashion attaching importance to the women’s movement, and she filled up the simplicity of her garments. Dior made a huge success by showing the feminine beauty which was concealed under the military look of women who worked instead of men during the war. His design was more sensual and showy than those of Chanel. Schiaparelli, who presented a remarkable and endless changing ornaments under surrealism when the core was moving to the United States because of the World war, Gustavo Trifari of Napoli, who succeed by processing materials and technology development, Coppola e Toppo from Milan who was famous for a spectacular biz necklace, Hatte Carnegie, Fernand Steinberger from Austria, who made colorful animal shaped custom jewels Lea stein, made of synthetic resins, Stanly Hangler from U.S. who is famous for his ornaments made by colorful glasses braided densely lead the time. At that time America could have prosperous days because of the cheap manpower from different countries, the technology of ornament industry and a capital for it from the Jews who avoided the Nazi. However, in the later 20th century, as the industries of U.S grew, the economic structure changed from manufacturing industry to service industry and financial business, and the U.S began to produce by outsourcing, and during the 1980’s and 1990’s, Korea was an important outsourcing country. However, these days, the China, which is led by cheap labor, is a representative jewel producer. Our Costume Jewelry enterprises have enough technology and knowledge accumulated by an old OEM export system, and Korea is throwing up the largest amount of ornament majored University graduated students in the world every day because of enthusiastic education, having the largest labor. Therefore, now we also should make our own high classed brand in the custom Jewel industry.

시그마 수준과 계산 방법에 대한 고찰

박준오,박성현 한국품질경영학회 2003 품질경영학회지 Vol.31 No.2

It is very important to understand and interpret the meaning of the sigma level correctly through the Six Sigma project. Especially, the confusion over the relation between sigma level from the short-term point of view and defective proportion or DPMO from the long-term point of view may make a big gap between expected results of the Six Sigma project and real results in the field. The one-tail approximation is commonly used to calculate the sigma level both in most literatures introducing Six Sigma and actual cases of the Six Sigma project. Since the one-tail approximation undervalues the sigma level of the fields such as business and service of which the sigma level is generally low, however, there can be misleading results of the explanation of the sigma level and inappropriate project evaluation. This paper describes the relation between sigma level and defective proportion in detail and clears the difference between the one-tail and two-tail approximation.

Wide Angle BPM 을 이용한 광도파로열 격자 파장 필터의 해석

박준오,정영철,Park, Jun-O,Jeong, Yeong-Cheol 대한전자공학회 2002 電子工學會論文誌-SD (Semiconductor and devices) Vol.39 No.2

광도파로열 격자(AWG :Arrayed Waveguide Grating) 파장 필터는 전광 네트웍(All Optical Network)을 실현하는 매우 중요한 핵심 소자 중에 하나이다. 광도파로열 격자 파장 필터와 같은 광도파 소자를 해석 및 설계시 수학적인 해석이 필요하며, 가장 대표적인 방법은 BPM(Beam Propagation Method)이다. 본 논문에서는 Paraxial BPM과 Wide Angle BPM을 InP/InGaAsP/InP 광도파로열 격자 파장 필터 해석에 적용시켜 정화도의 차이를 고찰해 보았다. WA-BPM을 구현하기 위하여 저차의 Pade Approximant를 적용하였다. 광도파로열 격자 파장 필터의 SLL(Side Lobe Level)과 삽입손실(Insertion Loss)을 비교하여 분석하였다. 광도파로열 격자 파장 필터를 정확하게 해석 및 설계하기 위해서는 고차의 WA-BPM을 사용해야 함을 확인하였다. The key component to accomplish the WDM all optical network is an Arrayed Waveguide Grating(AWG) wavelength filter Numerical analysis is necessary for design and analysis of optical components like AWG wavelength filter. Beam Propagation Method(BPM) is the most widely-used method. In this paper, we analyze the difference between the paraxial BPM and the WA-BPM when they are applied to the analysis of InP/InGaAsP/InP AWG wavelength filter. The paraxial BPM is based on paraxial approximation, and the WA-BPM is based on the low order Pade approximant. The side lobe level(SLL) and insertion loss calculated from both methods are compared. The high order Pade approximant will to used to more accurate design and analysis of AWG.

전 교통 동맥 동맥류 치료의 예후인자

박준오,권택현,박윤관,정흥섭,이훈갑,서중근,Park, Juno,Kwon, Taek-Hyun,Park, Youn-Kwan,Chung, Hung-Seob,Lee, Hoon-Kap,Suh, Jung-Keun 대한신경외과학회 2001 Journal of Korean neurosurgical society Vol.30 No.5

Objective : The anterior communicating artery(ACoA) is known to be the most frequent location of intracranial aneurysms, but the complex arterial anatomy of the ACoA region makes this aneurysm among the most difficult one to treat. In the treatment of ACoA aneurysms, the direction of aneurysmal fundus is known to be very important in the surgical tactics. All ACoA aneurysms in our series were classified according to its direction, and analyzed the clinical features in order to investigate the prognostic factors influencing upon the surgical outcome. Methods : The authors reviewed 236 cases of ruptured ACoA aneurysms that were operated from 1990 to 1997, were classified according to Pia's classification. Results : The incidence rate of the ACoA aneurysm was 35.1%(236/672). Ventral group was more common than dorsal group, especially in ventro-caudal projection subgroup(36.0%). Poor preoperative clinical grade(Hunt-Hess grade IV and V) patients were more common in dorsal group(13.1%) than ventral group(2.6%). Rebleeding and intracerebral hematoma were more commonly seen in ventral group. However, vasospasm, hydrocephalus, hyponatremia, and intraventricular hemorrhage were observed more frequently in dorsal group. Worse outcome was more common in dorsal group than ventral group, especially in dorso-caudal projection subgroup. Also, poor outcome was identified in patients with intracerebral hematoma, intraventricular hemorrhage, hyponatremia, and hypertension, although statistically insignificant. In cases with the A1 dominancy, there was no difference in surgical outcome between the right and left side approach. The higher the aneurysmal neck from the planum sphenoidale, the worse outcome via pterional approach. Conclusion : It seems that the preoperative clinical grade, aneurysmal direction, and the height of aneurysmal neck, especially in the pterional approach, would be the major prognostic factors, and that intracerebral hematoma, intraventricular hemorrhage, hyponatremia, hydrocephalus and the intraoperative aneurysmal rupture would be the minor prognostic factors.