Current-Fed Push-Pull Type High Frequency Resonant Inverter for Wax-Sealing

Kim, Dong-Hee,Won, Jae-Sun 영남대학교 공업기술연구소 2001 工業技術硏究所論文集 Vol.29 No.1

본 논문에서는 wax-sealing용 전원장치로써 사용되는 부하 공진 방식의 2석형 전류공급 Push-Pull형 인버터 회로를 제안하고 있다. 제안한 인버터는 공진용 커패시터를 ZVS용 커패시터로 사용함으로서 ZVS동작을 실현할 수 있고, 또한 기존의 1석형 전류공급 Push-Pull형 인버터에 비해서 스위치의 전류부담을 감소시킬 뿐만 아니라 부하의 사용범위가 현저하게 넓다는 장점을 가지고 있다. 제안 회로의 해석은 무차원화 파라메터를 도입하여 설계 전 단계에 필요한 특성평가를 무차원화 주파수(μ)와 무차원화 저항(λ) 및 제 파라메터에 따라 범용성 있게 기술하였다. 또한, 이론해석에서 얻은 특성값을 기초로 한 회로 설계 기법의 일 예를 제시하였다. 실험을 통해 이론 해석의 정당성을 입증하였으며, 본회로는 향후 wax-sealing용 전원장지, DC-DC 컨버터 등의 전원 시스템에 응용 가능성을 보여주고 있다.

나일론/면 교직물의 최적 염색기술 개발에 관한 연구

김삼수 嶺南大學校 工業技術硏究所 1994 工業技術硏究所論文集 Vol.22 No.1

The aim of this study is to develop a new and improved method of a dyeing process for nylon/cotton fabrics. The dyeing property was highly dependent on the characteristics of each fabrics, the affinities of the dyestuffs, the concentration of the salts, the levelling agents, and the reserving agents. Results indicated that optimum dyeing method for nylon/cotton fabric was the use of mixed acid dye and reactant-fixable dye with an appropriate concentration of the salt, the reserving agent, and the levelling agent.

순환메모리를 이용한 비디오 데이터 연속저장이 가능한 휴대형 켐코더 전화기의 설계

서영석 嶺南大學校 工業技術硏究所 2004 工業技術硏究所論文集 Vol.32 No.2

A new mobile camcorder type telephone has been designed. The telephone can record continuously the moving picture with the finite volume of memory. The phone has the circular type memory for the continuous video recording. The generated current video data stream is overwritten on the oldest region of the recorded video data. The telephone has an external interface port for the small remote camera module to catch the scene around the user, and has the acceleration sensor to detect the impact on the device. In an emergency, the camcorder phone can record the surroundings of an user and send the video data to the other remote user.

마이크로 광 조형기술과 이를 이용한 3차원 미세구조물의 제작

이인환 嶺南大學校 工業技術硏究所 2004 工業技術硏究所論文集 Vol.32 No.1

Micro-stereolithography is a newly proposed technology as a means that can fabricate a 3D micro-structureof free form. It makes a 3D micro-structure by dividing the shape into many slices of relevant thickness along horizontal surfaces, hardening each layer of slice with a focused laser beam, and stacking them up to a desired shape. To realize micro-stereolithography technology, the micro-stereolithography apparatus which is composed of an Ar+ laser, x-y-z stages, controllers and optical devices was developed. Using this technology, two kind of applications were fabricated and tested: micro-lens and micro-mixers. The focusing ability of the micro-lens was verified by defocusing the He-Ne laser beam after passing the lens. Two mixers are Kenics micro-mixerand BEKM. BEKM is a modified Kenics micro-mixer by introducing barriers on the pipe wall periodically to enhance the mixing via the chaotic mechanism in the helical flow of Kenics micro-mixer. Experimental result shows good mixing performance of developed mixers. Especially, the BEKM shows better mixing performance then Kenics micro-mixer.

Multivariate Analysis for the Factors influencing the Concentrations of Atmospheric Suspended Particulate Matter

Baek, Sung-Ok,Choi, Jin-Soo 嶺南大學校 工業技術硏究所 1993 工業技術硏究所論文集 Vol.21 No.1

본 연구는 대구-포항지역을 대상으로 주거지역, 전원지역 및 공업지역에서 측정된 대기중 부유분진의 농도에 영향을 미치는 각종 분진발생원의 기여도를 정량화하기 위하여 수행되었다. 이를 위하여 다변량해석법의 일환인 절대주성분분석법과 단계식 중회귀분석법을 적용하여 분진발생원을 규명하고 각 발생원별농도기여도를 추정하였다. 대구-포항지역에서 추정된 분진발생원중 주요한 원인은 토사(혹은 도로먼지)의 재비산, 연료연소, 자동차배기가스 및 대기중 이차생성입자들로 나타났으며 이들의 상대적 기여도는 측정지점별로 특징적인 상황을 대변하는 것으로 평가되었다. 본 연구의 결과 분진의 각 발생원별 농도기여도를 보다 정확히 추정하기 위해서는 무엇보다 각 발생원별 분진배출특성에 관한 상세한 자료의 확보가 중요한 과제임을 확인할 수 있었다. The purpose of this study is to quantitatively estimate the source contributions to the atmospheric suspended particulate matter(SPM) measured in urban residential, suburban, and industrial sites in Taegu-Pohang area. In this work, the techniques of principal component analysis(PCA) and stepwise multiple regression were employed to identify and quantify the major source classes influencing the ambient SPM. The mass contributions of the different source classes were estimated by the calculation of absolute principal component scores(APCS), and the subsequent stepwise regression of the SPM concentrations on the APCS. The results indicated that major source classes of ambient SPM in Taegu-Pohang area are soil resuspension, fuel combustion, automotive emissions, and secondary aerosols. It is further emphasized that the compilation of an extensive inventory of such sources is an essential task, so that a more detailed apportionment of their contributions to the SPM can be made in Korea.

UHF 대역의 휴대전화 착신기능 제한 시스템의 설계 및 제작

남효덕,김종석,김병철 嶺南大學校 工業技術硏究所 2001 工業技術硏究所論文集 Vol.29 No.2

As demands grow for restricting use of cellular phones by attendants in the public places such as conference rooms, churches, and playhouses etc., a call blocking system against UHF band cellular signals is developed for other attendants who do not want to be disturbed by the phone rings. The idea of preventing a cellular phone from ringing was developed from the fact that the system radiates interferent signals having 0.1 to 0.05 watts of CW wave, makes it possible to increase the error rates of output signal of PSK modem, and hence makes the cellular phone Impossible to receive the right call signal. The system designed in this study was set up and tested in the several public places and found itself very effective.

집적화 용량성 센서용 인터페이스 회로

崔世崑,李允熙,徐熙敦 嶺南大學校 工業技術硏究所 1993 工業技術硏究所論文集 Vol.21 No.2

본 논문은 용량형 센서의 용량출력 신호를 검출하기 위한 용량-전압 변환 및 용량-주파수 변환 인터페이스 회로를 설계 및 제작한 것이다. 기생용량의 영향을 줄이기 위해 SC형 적분기를 이용한 용량-전압 인터페이스 회로와 슈미트 트리거 및 무안정 멀티바이브레이터를 이용한 용량-주파수 인터페이스 회로를 PSPICE를 이용하여 설계하고 CMOS 기술로 제작 하였다. 설계과정에서 출력특성의 온도의존성 문제를 개선하기 위하여 전원전압 조절방법과 CMOS 차동증폭기를 이용한 새로운 방법을 제안하였다. 이들 회로의 시뮬레이션과 실제 제작된 칩의 특성측정 결과온도의 영향은 전원전압의 약 2V일때 가장 적었으며 차동증폭기를 이용함으로써 훨씬 줄어들었다. 따라서 제작된 인터페이스 회로들은 집적화 용량형 압력센서의 용량검출회로로 사용될 수 있다. This paper describes the design and fabrication of C-F and C-V interface circuitry which convert the absolute capacitance into frequency and voltage in a capacitive sensor. These circuits are designed to minimize the offset of a stray capacitance using a schmitt trigger oscillator, an astable multivibrator and a switched capacitor integrator, respectively, and are fabricated on CMOS process. In order to improve the temperature dependency of the interface circuit, we report supply voltage and temperature unsusceptible method and novel circuit using CMOS differential amplifier. The results of the computer simulation and the experimental measurement show that the temperature shift is minimized when the gate source voltage is about 2V, and improved more and more by the differential amplifier circuit. The interface circuits can be used as the output signal detecting circuit of the integrated capacitive pressure sensor.

Shield Disk 상의 Ag-Cu 공정계 합금 도금기술 개발

윤경도,차동관,심기종,민봉기,최순돈,이상기 嶺南大學校 工業技術硏究所 2003 工業技術硏究所論文集 Vol.31 No.1

The composition and the microstructure of the Ag-Cu alloy electrodeposits electroplated in Succinimide bath were investigated varying the electrolysis conditions such as bath composition, current density and additive agents etc. The cathode overpotential increased with the increase of Succinimide concentration and current density ratio in the bath. The Ag content of the alloy deposits decreased with the increase of current density and pH and temperature in the bath. The optimum condition for 78wt.%Ag-22wt.%Cu code position alloy is an follows : pH10(adjusted by NH_4OH), 0.03M AgNO_3, 0.27M Cu(NO_3)_2 3H_2O, 0.5M Succinimide in bath and 3.5A/dm^2∼5.5A/dm^2 current density.

전도성 충전물을 이용한 도전성 판재의 제조기술 개발

남효덕,이현석,박봉국 嶺南大學校 工業技術硏究所 2003 工業技術硏究所論文集 Vol.31 No.1

As an effort of developing efficient materials for shielding EM waves, a fibrous sheet for shielding EMI is developed by adding conductive filler to fibrous sheet during hardening process. From the aspect that the conductivity is inversely proportional to the square value of the length of added material, the conductive filler is fabricated by electroless plating with nickel and copper to the polymer textile power which has very high anisotropy. The conducting sheet was also fabricated by applying proper amount of highly efficient conductive filler to the fibrous sheet. The results obtained by measuring the shielding characteristics of 1㎒∼1㎓ frequency range showed the EMI suppressing effectiveness of 10∼20 ㏈.

오존 발생기용 탄소복합 적극 제조기술 개발

한주환,이재춘,조수래 嶺南大學校 工業技術硏究所 2002 工業技術硏究所論文集 Vol.30 No.1

Ozone has been widely used in many industrial applications on an environmental pollution, because of its strong oxidation power. However, ozone generating electrodes whose electrolysis is performed in water will be used in environment-affinity products. In this study, on the basis of investigating all the possible materials for electrodes, We tried to develop carbon composite electrodes by various methods. the research was concentrated on the development of carbon-metal composite electrodes for proper price and bio-compatible feature.