BLDC 모터의 속도 제어를 위한 퍼지 가변 구조제어에 관한 연구

진광식,윤태성,박종락 國立 昌原大學校 産業技術硏究所 1998 産技硏論文集 Vol.12 No.-

This paper shows the efficiency of fuzzy integral variable structure controller(FIVSC) with sliding mode which outperforms a traditional variable structure controller(VSC). This approach of the FIVSC solves the chattering problem which has been occurred in VSC and is applied to brushless D.C. motor. The simulation results verify the efficiency of the FIVSC.

차세대 무선 통신 시스템을 위한 안테나 신기술

김형락,권세웅,황광선,윤영중 延世大學校 電波通信共同硏究所 2002 電波通信論文誌 Vol.6 No.1

차세대 통신 시스템에서 공통적으로 요구하는 소형화, 광대역화, 집적화추세에 따라 RF소자는 광대역화, 소형화, 집적화를 향해 발전하고 있으며 안테나 기술도 현재 추세에 발맞추어 소형화, 능동집적화, 광대역화를 통하여 개발 방향을 모색하고 있다. 본고에서는 현재 추세인 소형 안테나, 능동 안테나와 더불어 최근 관심이 집중되고 있는 임펄스 통신에 이용될 수 있는 초광대역 안테나 기술에 대해 소개한다. The technical trends of the next generation wireless communication are miniaturization, broad-band operation, and integration. Thus, in accordance with this trend, RF devices and components are being developed in such way, and same with the antenna. In this paper, technology of small antenna, active antenna, and ultra wideband antenna, which can be applied to impulse communication system, are introduced.

RTA 방법에 의한 Ti-실리사이드 형성과 그 특성

高正大,李光萬,崔致圭,洪性樂 제주대학교 1990 논문집 Vol.30 No.-

A rapid thermal annealing (RTA) apparatus capable of controlling the radiation power density were designed. The titanium silicide grown from thin film Ti (400Å)/Si(111) and TiSi₂.?(700Å)/Si(111) system was processed in an argon ambient by RTA apparatus at the temperature range of 450℃ to 950℃ for 5 to 60 second. The processed specimens had been charaterized by XRD, SEM and AES. From the XRD spectra the phases of the titanium silicides had been changed from Ti?Si₄to TiSi and then TiSi₂by increasing the annealing temperature. XRD and AES results showed that the phase of Ti-silicides was C54 TiSi₂ at annealing temperature of 850℃ for 30 second. The phase of titanium silicides were confirmed by the line shape Si L₂,₃VV and Ti L₃M₂,₃M₂,₃ Auger spectra.

"Dice와 fill" 방식을 이용한 1-3 압전복합재의 제조와 횡방향 단위 크기에 따른 압전특성 평가

김영덕,김광일,정우철,김흥락,김동수 한국비파괴검사학회 2002 한국비파괴검사학회지 Vol.22 No.4

NDT나 의료용 영상장치에 응용되는 압전복합체는 일반적인 세라믹이나 고분자 압전재료에 비하여 많은 장점을 가진다. 이들 응용분야에서는 전기기계결합게수가 높아야 하고, 음향임피던스가 낮아야 한다. 그러나, 압전복합제의 횡방향 단위 크기가 조밀하지 못한 경우 횡방향으로 전행하는 판파에 의한 불필요한 진동이 표면에 발생하게 된다. 횡방향 단위 크기와 세라믹 체적비에 따른 압전 특성을 조사하기 위하여 PMN-PZT 세라믹과 Epofix 에폭시로 에폭시의 폭을 달리하면서 1-3 형 압전복합체를 제작하였다. 제작된 1-3형 압전복합체의 두께방향 진동모드의 전기기계결합계수, 음향임피던스는 각각 0.36~0.64, 9.8~22.7 MRayl로 나타났으며, 횡방향 단위크기가 줄어들수록 횡방향 모드 공진 주파수가 증가하였다. The piezoelectric composites had many adventages in comparison qith conventional piezoelectric ceramics and piezopolymers for ultrasonic transducers used in NDT and in medical ultrasonic imaging. The electromechanical coupling coeffucient should be high and the acoustic impedance should be low in these applications. However, the cross-coupling with spurious oscillations caused lateral spatial scale. The thickness mode electomechanical coupling coefficient of 1-3 type of piezoelectric composites were 0.36 to 0.64, and the acoustic impedance of them were 9.8 to 22.7 MRayl. The lateral resonance frequency of 1-3 type piezoelectric composites shifted to high frequency region with decreasing lateral spatial scale.

지붕경사각 변화에 따른 막구조의 풍압 변화 특성

길용식,김동우,하영철,이광렬,김종락 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.1(구조계)

This paper describes on the results of 1:400 geometrical laboratory modeling of wind-induced point pressure on the membrane roof structure of Stadium with variable roof slopes. The wind flow for flat ground surface was simulated in a boundary wind tunnel at Kumoh National Institute of Technology. The roof slope of membrane structure changed into 5 types. The locations of wind pressures taps are distributed on the same upper and lower part of membrane roof. The resultant wind pressure for each measurement points are analysed on 2 categories. One is acting on upper direction, the other is lower direction. The results showed that in the case of upper direction the changes of wind pressures on the membrane roof are not dominant in regard to changing roof slope, but in lower direction wind pressures are increased at the rear part of roof with changing roof slopes.

FET형 마이크로센서 개발

손병기,박이순,서화일,고광락 경북대학교 센서기술연구소 1997 연차보고서 Vol.1997 No.-

FET형 마이크로센서 개발

손병기,박이순,서화일,권대혁,고광락 경북대학교 센서기술연구소 1996 연차보고서 Vol.1996 No.-

소수성 촉매를 이용한 수소동위원소 교환 반응 측정을 위한 순환 반응기

최희주,이한수,안도희,강희석,김광락 한국공업화학회 2002 응용화학 Vol.6 No.2

The catalytic rate constants of hydrophobic catalysts developed for the removal of tritium mainly generated in the pressurized heavy water reactors should be measured. A recycle reactor was designed and built for characterzing the long-term behavior of the catalyst performance at the various temperatures and gas velocities.The catalytic rate constants were measured at the apparent gas velocity of 0.5 m/s and the temperature of 60℃. The initial catalytic constant was 8.44×10^-4mol/g.sec. This value is much greater than that considered in the design of Wolsong Tritium Removal Facility.

FET형 반도체센서 및 시스템 개발

손병기,조진호,최평,박이순,서화일,권대혁,고광락 경북대학교 센서기술연구소 1996 연차보고서 Vol.1996 No.-

기존의 센서들의 난점을 극복할 수 있는 새로운 형태의 FET형 전해질(electrolyte :H^+, K^+, Ca^2+, Na^+)센서소자 및 분석 시스템의 개발을 중점적으로 추진하였으며, FET형 포도당센서 및 압력센서의 개별 FET형 센서에 관한 연구도 병행하였다. FET형 전해질센서를 이용한 휴대용 전해질 측정기와 desktop형 4채널 전해질 분석기를 제작하였다. 또한 이 시스템을 소형화하기 위한 주문형 아날로그-디지탈 변환기 내장형 CMOS 프로세서를 설계하고 검증하였다. The main object of this research is to develope a new FET type electrolyte(H^+, K^+, Ca^2+, Na^+) sensors and analysis system which can overcome the problems of the conventional sensors. Parallel researches on FET type sensors such as glucose and pressure humidity are also in progress. A portable electrolyte meter and desktop 4-channel electrolyte analysis system is fabricated. A customized CMOS processor with built-in analog-to-digital converter is designed and verified.

Morphological characteristics of plantaris tendon width, thickness, and length: Cadaveric study

Kwang-Rak Park,Digud Kim,Hyung-Wook Kwon,Mijeong Lee,Yu-Jin Choi,Jaeho Cho,Jeong-Hyun Park 대한체질인류학회 2021 대한체질인류학회 학술대회 연제 초록 Vol.64 No.-

The plantaris tendon is used by surgeons as a donor for hand tendon reconstruction and repair of knee or ankle ligaments. The purpose of this study is to identify the morphological characteristics of plantaris tendon thickness, width, and length in the Korean population and to provide anatomical basic data to help surgeons determine their suitability as donor for tendon graft. The dissection was performed on 108 lower limbs (65 male, 36 female) fixed in formalin mixture. Three points were set for measuring the width and thickness of the tendon; point A, the junction of the belly and tendon; point B, Center of length between point A and point C; point C, the point where the tendon begins to extend. The height of the cadavers was measured from the head to bottom of the heel, and the leg length from the anterior superior iliac spine to the tip of the lateral malleolus. The length of the tendon was measured from point A to the point where it was inserted into the calcaneal bone. As a result of comparing the tendon width and thickness at each point according to gender, the tendon thickness in male were significantly thicker than female (p = 0.39) only at point C. The tendons of male were significantly longer than female. As a result of calculating the ratio between height and leg length by converting the length of the plantaris tendon to 1, it was found to be 1: 2.48: 4.96, and there was no gender difference. In the plantaris muscle, the length proportion of muscle belly and tendon was 21.0%: 79.0%, and there was no gender difference. In this study, the width and thickness of the tendon were not different according to gender in the results except for thickness at the point C. There was a significant difference in the length of the tendon according to the gender, but there was no difference in the ratio or ratio according to the gender. This result will be useful as a basis for the surgeon to judge the suitability of the harvest for tendon graft.