24 채널 경락 전위 측정 시스템 개발에 관한 연구

이우철,사공석진,Lee, Woo-Cheol,SaKong, Sug-Chin 대한전자공학회 2005 電子工學會論文誌 IE (Industry electronics) Vol.42 No.3

The 24 channel meridian electric-potential measuring System consists of a main cpu module, bio-signal analog module, interface module, power module, personal computer. The graphic user interface program conveniently allows user to setup, calibrate, measure, store, and control the meridian electric-potential measuring system. This system and program will continually be evolved using a database of clinically correlated meridian electric-potential. A variety of system configurations gives it the ability to make a user-favorable environment for measuring. 개발된 24 채널 경락 전위측정 시스템의 구성은 마이컴 제어부, 생체신호 아날로그 증폭부, 인터페이스부, 전원장치, personal computer 등 이다. 사용자 인터페이스 프로그램은 이용자를 편리하게 구성하였으며, 측정의 편리성으로 calibration기능 및 자료의 저장 과 검색 기능을 하게 하였다. 경락 전위를 측정하기 위한 프로그램을 구성하여 제어 할 수 있게 하였다. 측정된 생체 전기 신호 자료의 분석을 통하여 각각의 위치에 대한 전위의 상호 분포를 비교하여 결과를 체계적으로 나타낼 수 있게 프로그램 처리 하였다. 다양한 종류의 측정 조건을 변화 할 수 있게 구성하여 경락 전위를 측정을 위한 이용자에게 유리한 측정 환경이 되게 하였다.

A Study on DC Changing Algorithm of the Line-Interactive UPS with Dual Converter Structure

이우철,유동상,Lee, Woo-Cheol,Yoo, Dong-Sang The Korean Institute of IIIuminating and Electrica 2005 조명·전기설비학회논문지 Vol.19 No.3

본 논문에서는 2개의 컨버터 구조를 갖는 삼상 계통 연계형 UPS에 대하여 연구한다. 삼상UPS시스템은 2개의 능동 전력 보상기 구조로 이루어져 있다. 하나는 직렬형으로 .전원전압과 동상의 전압원으로 동작하여 전원전압의 변동, 왜곡시에도 정현파 전원전류와 고역률을 갖도록 동작한다. 병렬형은 전원전압과 위상을 맞춘 종전의 정현파 전압원으로 동작하여 부하에 안정되고 낮은 THD를 갖는 정현파 전압을 공급한다. 본 논문에서는 직렬형, 병렬형 능동보상기에서 전원전압의 크기에 따라 충전 방법에 대하여 제시한다. 종전의 계통 연계형 UPS는 DC 충전과 출력전압을 동시에 제어하였는데, 2개의 컨버터 구조를 갖는 UPS 시스템에서는 직렬형 보상기도 DC 충전을 할 수 있어 직렬형과 병렬형을 사용한 충전 알고리듬을 연구할 필요가 있다. 따라서 DC link단의 전압을 안정시켜 본래의 직렬형, 병렬형 구조의 보상기의 안정성 향상에 기여할 수가 있다. 제안된 방법의 타당성은 시뮬레이션과 실험 결과를 통하여 입증된다. This paper presents a three phase Line-Interactive uninterruptible power supply(UPS) system with dual converter structure. The three phase UPS system consists of two active power compensator topologies. One is a series active compensator, which works as a voltage source in phase with the source voltage to have the sinusoidal source current and high power factor under the deviation and distortion of the source voltage. The other is a parallel active compensator, which works as a conventional sinusoidal voltage source in phase with the source voltage, providing to the load a regulated and sinusoidal voltage with low total harmonic distortion(THD). This paper presents in the series and parallel active compensator charging method depending on the amplitude of the source voltage. The conventional Line-Interactive UPS system is responsible for the DC charging and output voltage regulation at the same time, but UPS system with dual converter structure, a series active compensator can also charge the DC link. Therefore the charging algorithm using the series and parallel compensator needs to be researched. Therefore, by making the DC link voltage stable it can contribute the stability of series and parallel compensator. The simulation and experimental result are depicted in this paper to show the effect of the proposed algorithm.

A study on Reactor Parameter of Atmosphere Plasma Power Supply

Woo-Cheol Lee(이우철) 전력전자학회 2011 전력전자학술대회 논문집 Vol.2011 No.11

鐵原,春城 및 華川地域의 線地自然度 査定에 關한 硏究

이우철(Lee Woo-Tchul),백원기(Paik Weon-Ki),이철환(Cheol- Hwan Lee) 강원대학교 기초과학연구소 1989 기초과학연구 Vol.6 No.-

This study was carried out to determine degree of geeen naturality, in Cheolweon- gun, Hwacheon-gun, and Chunseong- gun, to surveyed the floristic composition of Mt. Myeongseong in Cheolweon- gun, Mt Seokryong in Hwacheon-gun, and Mt. Obong in Chunseon- gun, concentrated on this studied areas. The squre of studied areas were 2, 820㎢ and this area composed of 2, 665 meshes Nine different grades of green naturality; (1),(2),(3),(4),(5),(6),(7),(8),(9),(0) have been registered 1,673 meshes (62. 78%) out of 2, 665 were classified as the grade 8 and 389 meshes (14.6%) were the grade 7. The above data indicate that this areas composed of 20-50 years forests. Plant biomass, net production and oxygen production were estimated to be 15, 657, 330ton/year, 1,609, 590 ton/year, 1,706, 165.4ton/year in this area. Floristic composition of Mt. myeongseong (922.6m) was revealed to be 372 taxa, and that of Mt. Seokryong(1300m) wes 471 taxa, and that of Mt. Obong was 562 taxa. Among them 24 species were indigenous to Korea, including genera of Hanabusaya. It is interesting that north hemispheric plant. Astilboides tabularis was distributed at Mt. Seokryong.

한자와 중국어의 모사성과 이거(理據) 연구

이우철(Woo Cheol Lee) 언어과학회 2006 언어과학연구 Vol.39 No.-

원거리 공진 기동시 과전압 방지 HID 안정기

이우철(Woo-Cheol Lee) 한국조명·전기설비학회 2015 조명·전기설비학회논문지 Vol.29 No.1

The electronic ballast for HID lamps needs to ignite lamps even though the length from the ballast to lamp is far away. Therefore, it needs to do the research on a resonant ignition to turn on the HID lamps because the reduction of ignition voltage is not much depending on the distance. However, the parasitic capacitance is increased depending the length of the cable, and it affects the resonant frequency. The ignitor voltage can be increased drastically under the resonant ignition through frequency sweep, and it is the main reason of blowing up . Therefore, the clamping diode is proposed to suppress the voltage of the primary winding during resonant ignition.

단상 인버터 시스템에서 영 전압 근처 전압 강하 검출 기법에 관한 연구

이우철(Woo-Cheol Lee) 한국조명·전기설비학회 2014 조명·전기설비학회논문지 Vol.28 No.1

The all pass filter generates a virtual q-axis voltage component with 90° phase delay but the virtual q-axis voltage cannot detect the voltage depending on the phase of the grid voltage. To overcome the problem, q-axis voltage component is generated from difference between the current and previous value of d-axis voltage component in the stationary reference frame. However, the difference voltage between the current and previous value around the zero crossing voltage is not enough to detect the voltage sag. Therefore, the new detection scheme which can detect the sag around the zero crossing voltage is proposed.

중국어 서술성 주어의 명물화와 그 생성기제

이우철(Woo Cheol Lee) 언어과학회 2010 언어과학연구 Vol.54 No.-

프로그램 로직 기반의 스마트 최대 전력 관리 시스템에 관한 연구

이우철(Woo-Cheol Lee),권성현(Sung-Hyun Kwon) 한국조명·전기설비학회 2014 조명·전기설비학회논문지 Vol.28 No.2

The paper is related to smart maximum power system based on program logic. Especially, this system compares the total demand power with the target power by using the signal from the digital kilo watt meter. Based on the power information by the maximum power control equipment the consumed future power is anticipated. In addition, through consumed future power the controllable target power is set, and it applies on the maximum power control equipment. User or manager would control the load efficiently through the simple programming which could control load based on the control sequence and relay. To begin with the conventional maximum power control algorithm is surveyed, and the smart maximum power control system based on program logic is used, and the new algorithm from full load to proportion shut down is proposed by using PLC program. the validity of the proposed control scheme is investigated by both simulation results.

경락 임피던스 측정 시스템 개발에 관한 연구

李雨哲(Woo-Cheol Lee),印昌植(Chang-Shik Yin),閔庚基(Kyoung-Kee Min) 대한전기학회 2009 전기학회논문지 Vol.58 No.2

Meridian which used as the basic theory of acupuncture treatment, is an important functional connection system of acupuncture point in oriental medicine. Yangdorak and EAV have lack of precision because of using 2-electrode method, occurring high non-uniformed current density and electrode contact status on electrode placement spot. Therefore we implemented a meridian impedance measurement system for measuring meridian impedance using 4-electrode method. In order to confirm the precision of developed system, we made an constant current characteristic experiment using standard resistor. As a results of clinical study with 18 subjects, the meridian impedance showed that reproductivity and repeatability of HTI acupuncture point are 0.515[㏀]±0.000(mean±standard deviation} and 0.515[㏀]±0.002, respectively. And reproductivity and repeatability of PC7 are 0.521[㏀]±0.000 and 0.52l[Ω]±0.001, respectively. The proposed system was stable and reliable. Therefore this study proved AC impedance method to valid in measuring meridian impedance, and also verified precision and repeatability of the proposed meridian impedance measurement system. The proposed system will serve as more effective method of measuring meridian phenomena as a bioelectric signal in clinical practice.