위상잡음 제거에 의한 광섬유망에서의 높은 안정도의 RF 전송

이원규,이대수,김영범,권택용,Lee, Won-Kyu,Yee, Dae-Su,Kim, Young-Beom,Kwon, Taeg-Yong 한국광학회 2006 한국광학회지 Vol.17 No.6

높은 안정도를 가지는 100 MHz의 RF 신호를 23 km의 광섬유망을 통하여 전송하였다. 진동과 온도 변화에 의하여 생기는 광섬유 전송과정에서의 위상 잡음을 측정하고 이를 보상하는 회로를 구성하였다. 광섬유 잡음이 제거되었을 때, RF 신호 전송의 상대주파수 불안정도는 1초 평균시간에서 $6{\times}10^{14}$, 10000초 평균시간에서 $2{\times}10^{-17}$으로서 기준 RF 신호의 안정도와 거의 같은 수준으로 광섬유를 통하여 RF를 전송할 수 있었다. 잡음 보상에 의하여 단측파대 위상잡음은 푸리에 주파수 1 kHz 이하에서 20 dB 이상 감소하였다. We have transferred highly stable 100 MHz RF through a 23 km fiber network. The fiber-induced phase noise due to the vibration and the temperature fluctuation in the optical path is detected and is compensated by configuring a noise-canceling servo. The transfer instability was $6{\times}10^{14}$ at 1 s of averaging time and $2{\times}10^{-17}$ at 10000 s of averaging time. The single sideband phase noise was greatly reduced by more than 20 dB below the Fourier frequency of 1 kHz. The transferred RF has nearly the same stability as the original reference frequency.

광섬유를 통한 광 주파수 전송에서 광 위상 잡음의 능동 제거

이원규,김재완,유한영,김억봉,Lee, Won-Kyu,Kim, Jae-Wan,Ryu, Han-Young,Kim, Eok-Bong 한국광학회 2007 한국광학회지 Vol.18 No.1

광섬유 망을 통해 수 kHz의 좁은 선폭을 가지는 $1.5{\mu}m$ 레이저광원을 높은 전송 안정도로 전송하였다. 525 m 길이의 단일모드 광섬유를 통과하면서 발생하는 광 위상 잡음을 능동적으로 제거하는 실험 장치를 구성하였고, 이렇게 하여 전송된 광 주파수의 전송 안정도는 1 초의 평균시간에서 $2{\times}10^{-17}$로 측정되었다. 전송된 광 주파수의 품질을 주파수 영역과 시간 영역에서 정량적으로 분석하였다. We have transferred a narrow-linewidth $1.5{\mu}m$ laser beam through a 525 m fiber network with excellent transfer stability. The fiber-induced optical phase noise during the fiber transmission is cancelled by configuring a noise-canceling servo. The transfer instability was $2{\times}10^{-17}$ at 1 s of averaging time. We quantitatively analyzed the transferred optical frequency in the frequency domain and in the time domain.

1930년대 중국 문서당안 행정개혁론의 이해

이원규,Lee, Won-Kyu 한국기록학회 2004 기록학연구 Vol.0 No.10

Historical interest in China in 1930s has been mostly focused on political characteristic of the National Government(國民政府) which was established by the KMT(中國國民黨) as a result of national unification. It is certain that China had a chance to construct a modern country by the establishment of the very unified revolutionary government. But, it was the time of expanding national crises that threatened the existence of the country such as the Manchurian Incident and the Chinese-Japanese War as well as the chaos of the domestic situation, too. So it has a good reason to examine the characteristic and pattern of the response of the political powers of those days. But, as shown in the recent studies, the manifestation method of political power by the revolutionary regime catches our attention through the understanding of internal operating system. Though this writing started from the fact that the Nationalist Government executed the administrative reform which aimed at "administrative efficiency" in the middle of 1930s, but it put stress on the seriousness of the problem and its solution rather than political background or results. "Committee on Administrative Efficiency(行政效率委員會)", the center of administrative reform movement which was established in 1934, examined the plan to execute the reform through legislation by the Executive Council(行政院) on the basis of the results of relevant studies. They claimed that the construction of a modern country should be performed by not political revolution anymore but by gradual improvement and daily reform, and that the operation of the government should become modern, scientific and efficient. There were many fields of administrative reform subjects, but especially, the field of records and archives adminstration(文書檔案行政) was studied intensively from the initial stage because that subject had already been discussed intensively. They recognized that records and archives were the basic tool of work performance and general activity but an inefficient field in spite of many input staff members, and most of all, archival reform bring about less conflicts than the fields of finance, organization and personnel. When it comes to the field of records adminstration, the key subjects that records should be written simply, the process of record treatment should be clear and the delay of that should be prevented were already presented in a records administrative meeting in 1922. That is, the unified law about record management was not established, so each government organization followed a conventional custom or performed independent improvement. It was through the other records administrative workshop of the Nationalist Government in 1933 when the new trend was appeared as the unified system improvement. They decided to unify the format of official records, to use marker and section, to unify the registration of receipt records and dispatch records and to strengthen the examination of records treatment. But, the method of records treatment was not unified yet, so the key point of records administrative reform was to establish a unified and standard record management system for preventing repetition by simplifying the treatment procedure and for intensive treatment by exclusive organizations. From the foundation of the Republic of China to 1930s, there was not big change in the field of archives administration, and archives management methods were prescribed differently even in the same section as well as same department. Therefore, the point at issue was to centralize scattered management systems that were performed in each section, to establish unified standard about filing and retention period allowance and to improve searching system through classification and proper number allowance. Especially, the problem was that each number syst

Synthetic Pathway of Indole Acetic Acid in Azospirillum Lipoferum

이원규,이정열,강규영,조무제,Lee, Won-Kyu,Lee, Joung-Yeoul,Kang, Kyu-Young,Cho, Moo-Je 생화학분자생물학회 1988 한국생화학회지 Vol.21 No.4

Azospirillum lipoferum SK16에서 tryptophan으로부터 indole-3-acetic acid (IAA)의 생합성 경로를 규명하기 위하여 tryptophan을 첨가하여 배양한 배양액 및 초음파 파쇄한 세포추출물에서 IAA 합성 중간대사물들을 TLC 및 HPLC 로 분석한 결과 tryptophan$\rightarrow$indole-3-pyruvate$\rightarrow$indole-3-acetaldehyde${\rightarrow}$IAA의 주 생합성 경로가 확인됨과 동시에 tryptophan에서 tryptamine을 거치는 부수적인 합성경로도 있는 것으로 추정되었다. The synthetic pathway of indole-3-acetic acid (IAA) from tryptophan in Azospirilium lipoferum SK16 was examined by analysis of IAA intermediates with thin layer chromatography (TLC) and high performance liquid chromatography(HPLC). Analysis of the IAA intermediates from A. lipoferum SK16 culture broth and cell extract by the TLC and HPLC have indicated that the major synthetic pathway from tryptophan to IAA is via tryptophan$\rightarrow$indole-3-pyruvate$\rightarrow$indole-3-acetaldehyde$\rightarrow$IAA. For the confirmation of the pathway, tryptophan aminotransferase, the enzyme catalyzing the first reaction from tryptophan to IAA, was examined in cell free extract and the result of the enzymatic analysis Was well coincided with the data of IAA intermediate analysis in the culture broth. Minor pathway of IAA synthesis via tryptamine was also speculated in A. lipoferum SK16.

공공기록물의 수집·이관과 아키비스트의 역할

이원규,Lee, Won-Kyu 한국기록학회 2000 기록학연구 Vol.0 No.2

The collection and transfer of records is a very basic stage in the whole process of records and archives management. However they are regarded as an non-professional art of work in records management that are performed easily by everyone. Therefore they have been treated not properly in the scholarly discussion of archival sciences in Korea. The collection and transfer of records play an active role in the making of effective administrative system, in accumulating and sharing the knowledge and informations of political, economical, social and cultural values. On the basis of proper collection and transfer of records our democracy can operate regularly and our daily experiences can be preserved as historical resources. For the optimal-functioned collection and transfer of public records the archivists for this task must have a comprehensive understanding of whole process of records management and possess suitable professional skills. Moreover there are many sorts of preliminary works needed for this task, as follows: an accurate defining of administrative organizations and their tasks, thorough understanding of records management institutions on their own competence and ability, and the establishment of technical standards for their tasks. Additionally the archivists are able not only to consider the present informational and evidential values of the records, but also the historical values. It can be said that the collection and transfer of records is a "synthesis of records management skills" exerted by an archivist. According to the newly established law of public records management, the collection and transfer of public records must be registered at first electronically. Through this procedure the whole contents of produced and transmitted records, which are to be transferred, can be reported in detail. By means of this report the archival institutions and the archivists can trace back the each items of records(archives) and the result of their arrangement to identify a certain object. There are also new storage strategies employed to increase the whole sum of stored informations, i. e. records and archives, in spite of reducing the storage costs. It will be achieved by differentiations of the preservation methods for each sorts of records by the criteria of storage-period, -place, and -method. Many supplementary methods are also prepared to help the collection of important records(archives) in a complete structure and form. To let this new concept and system of collection and transfer of records operate properly, a number of professional archivists should be posted in the needed places throughout the whole administrative body. Their training must be also updated for the newly defined task of collection and transfer of records.

침대 패드 형태의 용량성 전극에서 측정된 심전도 신호를 처리하기 위한 자동 잡음 제거 및 피크 검출 알고리즘

이원규,이홍지,윤희남,정기성,박광석,Lee, Won Kyu,Lee, Hong Ji,Yoon, Hee Nam,Chung, Gih Sung,Park, Kwang Suk 대한의용생체공학회 2014 의공학회지 Vol.35 No.4

Recent technological advances have increased interest in personal health monitoring. Electrocardiogram(ECG) monitoring is a basic healthcare activity and can provide decisive information regarding cardiovascular system status. In this study, we developed a capacitive ECG measurement system that can be included within a cloth mattress pad. The device permits ECG data to be obtained during sleep by using capacitive electrodes. However, it is difficult to detect R-wave peaks automatically because signals obtained from the system can include a high level of noise from various sources. Because R-peak detection is important in ECG applications, we developed an algorithm that can reduce noise and improve detection accuracy under noisy conditions. Algorithm reliability was evaluated by determining its sensitivity(Se), positive predictivity(+P), and error rate(Er) by using data from the MIT-BIH Polysomnographic Database and from our capacitive ECG system. The results showed that Se = 99.75%, +P = 99.77%, and Er = 0.47% for MIT-BIH Polysomnographic Database while Se = 96.47%, +P = 99.32%, and Er = 4.34% for our capacitive ECG system. Based on those results, we conclude that our R-peak detection method is capable of providing useful ECG information, even under noisy signal conditions.

Azospirillum lipoferum 의 Indole Acetic Acid 생합성 경로

이원규,이정열,강규영,조무제 ( Won Kyu Lee,Joung Yeoul Lee,Kyu Young Kang,Moo Je Cho ) 생화학분자생물학회 1988 BMB Reports Vol.21 No.4

The synthetic pathway of indole-3-acetic acid (IAA) from tryptophan in Azospirillum lipoferum SK16 was examined by analysis of IAA intermediates with thin layer chromatography (TLC) and high performance liquid chromatography(HPLC). Analysis of the IAA intermediates from A. lipoferum SK16 culture broth and cell extract by the TLC and HPLC have indicated that the major synthetic pathway from tryptophan to IAA is via tryptophan → indole-3-pyruvate → indole-3-acetaldehyde → IAA. For the confirmation of the pathway, tryptophan aminotransferase, the enzyme catalyzing the first reaction from tryptophan to IAA, was examined in cell free extract and the result of the enzymatic analysis was well coincided with the data of IAA intermediate analysis in the culture broth. Minor pathway of IAA synthesis via tryptamine was also speculated in A. lipoferum SK16.

13 km 광섬유를 통하여 원격지로 전송된 1.4 GHz RF 신호의 위상잡음 제거

이원규,박창용,문종철,유대혁,Lee, Won-Kyu,Park, Chang-Yong,Mun, Jong-Chul,Yu, Dai-Hyuk 한국광학회 2010 한국광학회지 Vol.21 No.3

13 km 광섬유를 통해 1.4 GHz의 기준 주파수를 전송할 때, 광섬유에서 발생하는 위상잡음을 제거하는 시스템을 구성하였다. 전송된 주파수의 안정도 성능은 실험장치의 온도변화폭에 의존하였다. 실험실의 온도변화폭이 $0.3^{\circ}C$ 이내로 유지되는 동안에는 광섬유의 위상잡음을 제거했을 때, 원격지에 전송된 신호가 0.8초의 평균 시간에서 $4.6{\times}10^{-14}$, 1000초의 평균 시간에서 $2.5{\times}10^{-16}$의 상대주파수 전송 안정도를 보여 만족할 만한 결과이었으나, 실험실의 온도가 $3.5^{\circ}C$ 범위로 변할 때에는, 1.2초의 평균 시간에서 $6.8{\times}10^{-14}$, 1000초의 평균 시간에서 $3.0{\times}10^{-15}$의 전송 안정도를 보였다. 이 결과로부터 1000초의 평균시간에서 $10^{-16}$ 수준의 상대주파수 안정도를 얻기 위해서 요구되는 실험장치의 온도 안정도 조건을 제시할 수 있었다. A fiber-phase-noise compensating system was constructed for a 1.4 GHz reference frequency transferred through a 13-km-long fiber spool. The transfer instability was dependent on the temperature variation of the compensating system. With the room temperature variation stabilized within $0.3^{\circ}C$, the transfer instability was $4.6{\times}10^{-14}$ at 0.8 s of average time and $2.5{\times}10^{-16}$ at 1000 s of average time with the fiber phase noise compensated. However, with the room temperature changed by $3.5^{\circ}C$, the transfer instability was $6.8{\times}10^{-14}$ at 1.2 s of average time and $3.0{\times}10^{-15}$ at 1000 s of average time. From this result, the temperature stability condition for the experimental setup could be determined to obtain a transfer instability of $10^{-16}$ at 1000 s of average time.

초공진기를 이용한 노란색 레이저의 선폭 축소 및 초공진기의 예리도 측정

이원규,박창용,박상언,유한영,유대혁,문종철,서호성,Lee, Won-Kyu,Park, Chang-Yong,Park, Sang-Eon,Ryu, Han-Young,Yu, Dai-Hyuk,Mun, Jong-Chul,Suh, Ho-Suhng 한국광학회 2010 한국광학회지 Vol.21 No.3

이터븀 광격자 시계의 검색 레이저로 쓰기 위하여, WG-PPLN를 사용하여 1319 nm 파장의 Nd:YAG 레이저와 1030 nm 파장의 Yb 도핑된 광섬유 레이저의 합주파수 (578.4 nm)를 발생시켰다. 이터븀 광격자에서 시계 전이선을 분광하기 위해서는 1 Hz 수준의 선폭을 가지는 검색 레이저가 필요하기 때문에, 합주파수로 발생된 노란색 레이저의 주파수를 초공진기에 안정화하여 선폭을 축소하였다. 초공진기는 선팽창 계수가 낮은 ULE로 제작되었고, 진동으로 인한 영향이 작은 받침점에서 능동형 제진대 위에 설치되었다. 공기 굴절률의 영향을 제거하기 위하여 이 초공진기를 진공 체임버 내부에 설치하고, 온도를 1 mK 수준에서 안정화 하였다. 또한, 이 장치들을 방음 체임버 안에 설치하여, 소리로 인한 잡음을 막아 주었다. 실험에 사용된 초공진기의 광자 수명시간으로부터, 그 예리도가 380 000으로 측정되었다. Sum frequency generation was utilized to obtain a yellow laser with the wavelength of 578.4 nm for a probe laser of an Yb lattice clock. The output of an Nd:YAG laser with wavelength of 1319 nm and that of an Yb-fiber laser with wavelength of 1030 nm were passed through a waveguided periodically-poled lithium niobate (WG-PPLN) for sum frequency generation. It is required that the probe laser has a linewidth of the order of 1 Hz to fully resolve the Yb lattice clock transition. Thus, the linewidth of the probe laser was reduced by stabilizing the frequency to a super-cavity. This was made of ULE with a low thermal expansion coefficient, and was mounted on an active vibration-isolation table at the optimal point for the reduced sensitivity to vibration. Also, this was installed in a vacuum chamber, and the temperature was stabilized to 1 mK level. This system was installed in an acoustic enclosure to block acoustic noise. The finesse of the super-cavity was measured to be 380 000 from the photon life time of the cavity.

진공유중건조를 이용한 유기성슬러지 건조 연료화 기술

이원규(Won-kyu Lee),서범문(Beom-moon Seo),유정근(Jung-kun Yoo),강희생(Hi-saeng Kang),박봉천(Bong-chun Park) 한국열환경공학회 2010 한국열환경공학회 학술대회지 Vol.2010 No.춘계