서울특별시에서의 공기 오염도 측정

권상욱,김면섭,Kwon, Sang-Wook,Kim, Myon-Sop 대한화학회 1965 대한화학회지 Vol.9 No.3

서울특별시 을지로 입구 네거리에서 1964년 8월 1일과 1965년 3월 6일에 대기의 오염도를 측정하였다. 자동차 폐가스로 오염되리라 생각되는 유해 가스 중 Pb, $SO_2,\;NO2,$ CO 및 $CO_2$의 농도를 측정하였다. 동시에 교통량도 조사하였다. Pb의 농도의 범위는 $21{\sim}2{\mu}./m^3, SO_2는\;0.33{\sim}0.001ppm$., $NO_2는\;1.30{\sim}0.02ppm$., CO는 $40{\sim}<5ppm$., $CO_2$는 $0.040{\sim}0.034%$였다. 평균농도는 Pb $11.3{\mu}./m^3., SO_2 0.08ppm, NO_2 0.09ppm., $NO 0.37ppm., CO 16ppm 그리고 0.038%였다. 일반적으로 Pb, NO2, NO, CO, $CO_2$의 농도는 교통량과 정비례하였다. 또 겨울 철에는 연탄 폐가스로 인해 $NO_2,SO_2 NO, CO, CO_2$의 농도가 여름 철보다 많았다. The degree of atmospheric pollution from automobile engine exhausts has been measured at 1-ga, Eulchiro, Jung-ku, one of the heaviest traffic junctions in Seoul. By determining the concentrations of Pb, $SO_2, NO_2, NO, CO \;and\; CO_2$ in atmospheric air measured are as follows: Pb, $21{\sim}2 {\mu]g./m^3.;\;SO_2,\;0.33{\sim}0.001\;ppm.;\;NO_2,$ $0.20{\sim}< 0.01\;ppm.;\;NO,\;1.30{\sim}0.02\;ppm.;\;CO,\;40{\sim}<\;5ppm$.; and $CO_2,\;0.040{\sim}0.034%$. The mean concentrations determined are as follows: Pb, $11 {\mu}g./m^3.; SO_2, 0.08 ppm.; NO_2,$ 0.09 ppm.; NO, 0.37 ppm.; CO, 16 ppm. and $CO_2,$ 0.038%. Generally, the concentrations of Pb, $NO_2, NO, CO\; and\; CO_2$ are approximately proportional to the traffic density, vehicles passing per hour.

합성 Dawsonite의 물리적, 화학적 성질

권상욱,Kwon Sang Wook 대한화학회 1969 대한화학회지 Vol.13 No.2

$NaAl(OH)_2CO_3$was synthesized using colloidal earth (Allophane) as the starting material and some of its were studied in detail. It was found that Dawsonite was formed in the pH range (pH 12.5~12.0) that the concentration of $HCO_3^-$ was just begun to increase and the presence of $HCO_3^-$ in the product was clarified from the infrared absorption spectrum. The chemical formular of Dawsonite was therefore presumed as $NaAlO (OH) HCO_3$. From toahhe results of X-ray powder diffraction, both peaks at 5.7 $\AA$ and 2.8 $\AA$ were observed, and fibrous crystalline structure was observed from electron micrograph and also found from the microscopic electron diffraction at 5.7 $\AA.$ Therefore the fibrous axis was considered as =Al=O2=Al=O2=Al=(*image) direction. True specific gravity of Dawsonite was 2.44 and its porosity was 91.4%. It was practically insoluble in water, but decomposed in the boiling water to form Pseudo Boehmite. Stable pH range of Dawsonite was about 4.5~11.5. From the results of D.T.A. and T.G.A., it was observed that $CO_2$was liberated at $350^{\circ}C$, and $H_2O$ at $650^{\circ}C$, and converted into strongly hygroscopic $NaAlO_2$, which was easily decomposed in water into $\beta-Al(OH)_3(Bayerite)$ and NaOH.

MEMS 기술을 이용한 온도, 압력, 습도 복합 센서

권상욱,원종화,Kwon Sang-wook,Won Jong-Hwa 대한전자공학회 2005 電子工學會論文誌-SD (Semiconductor and devices) Vol.42 No.11

본 논문은 MEMS (Micro-Mechanical-Electronic System) 기술을 이용한 온도, 압력, 습도 복합 센서의 설계와 제작, 그리고 평가에 관한 것이다. 이러한 MEMS 복합 센서는 휴대 전화나 PDA와 같이 가정용 제품에 사용되어 환경을 모니터링하는 건강 측정용 센서로서 사용될 것이다. 이 연구의 범위는 이러한 개별 센서의 연구 및 모든 센서를 하나의 실리콘 웨이퍼 상에서 집적할 수 있는 구조에 관한 연구, 그리고 복합 센서를 MEMS 공정에서 제작할 수 있는 공정 호환성에 대한 연구와 얻어진 센서 prototype의 측정, 평가로 이루어져 있다. 이 연구에서 우리는 온도와 압력 센서의 경우에는 선형성과 이력특성이 $1\%FS$안에 들어오는 특성을 얻었으며 단지 습도 센서의 경우에는 $5\%FS$에 해당하는 선형성과 이력 특성을 얻었다. 다만 원리적으로 습도 센서의 동작 특성은 비선형적이며 우리가 3차로 근사화할 경우에 보다 낳은 결과를 얻을 것을 기대할 수 있다. 이러한 특성을 더욱 개선하기 위한 것은 추후의 연구 영역이 될 것이다. In this paper, we present design and prototyping of a low-cost, integrated multi-functional micro health sensor chip that can be used or embedded in widely consumer devices, such as cell phone and PDA, for monitoring environmental condition including air pressure, temperature and humidity. This research's scope includes basic individual sensor study, architecture for integrating sensors on a chip, fabrication process compatibility and test/evaluation of prototype sensors. The results show that the integrated TPH sensor has good characteristics of ${\pm}\;1\%FS$ of linearity and hysteresis for pressure sensor and temperature sensor and of ${\pm}\;5\%FS$ of linearity and hysteresis But if we use 3rd order approximation for humidity sensor, full scale error becomes much smaller and this will be one of our future study.

膠質土酸, Alkali 處理에 의한 Dawsonite의 合成에 관한 硏究

권상욱,Kwon Sang Wook 대한화학회 1969 대한화학회지 Vol.13 No.2

Aoolphane was treated with 30% Hydrochloric acid at $18^{\circ}C$ for two hows with stirring in order to obtain the insoluble form of SiO2 gel and to extract quantitatively both $Al_2O_3$as and $Fe_2O_3AlCl_3{\cdot}6H_2O Fe$ and $Cl_3{\cdot}6H_2O$ forms, respectively, at the same time. $SiO_2$ gel was filtered and to the filterate Ammonia was added to precipitate $Al(OH)_3[Fe(OH)_3 Contaminated ]$ The precipitate was separated by filteration and the filterate was recovered as the form of $NH_4Cl$. The precipitate was treated with 200g (NaOH)/l Concentration of NaOH a little excessively to the equivalent at $65~70^{\circ}C$ as $Fe(OH)_3$ formed was insoluble, it was filtered of and to the filterate containing $NaAl(OH)_4(OH_2)_2$Carbon dioxide gas was bubbled at $50^{\circ}C~90^{\circ}C$ to obtain the precipitate with excellent filterability and crystallinity. The product was certified to be Dawsonite $(NaAl(OH)_2CO_3)$ by X-Ray diffraction analysis at below $40^{\circ}C$, when $CO_2$ gas was bubbled into the relatively lower concentration of $NaAl(OH)_4(OH_2)_2$ solution, the precipitate of very fine particles was formed, which was hard to filter and with the Composition of $\alpha-Al_2O_3-H_2O$ (Boehmite).

Noise Cancellation Circuit 구조 및 향상된 PSRR Rejection 특성을 갖는 LDO 레귤레이터

권상욱(Sang Wook Kwon),도경일(Kyoungil Do),정장한(Jeong Jang Han),구용서(Yong-Seo Koo) 대한전자공학회 2020 대한전자공학회 학술대회 Vol.2020 No.8

낮은 대기전류 및 빠른 과도응답특성을 갖는 LDO 레귤레이터

권상욱(Sang-Wook Kwon),도경일(Kyoung-Il Do),서정주(Jeong-Ju Seo),우제욱(Jae Wook Woo),구용서(YongSeo Koo) 대한전자공학회 2019 대한전자공학회 학술대회 Vol.2019 No.6

This paper present a Low Drop Out regulator (LDO) that improves the road transient response characteristics by using a voltage regulator. A voltage regulator circuit is placed between the error amplifier and the pass transistor inside the LDO regulator to improve the current characteristics of the voltage line, The proposed Fast Transient LDO structure was designed by a 0.18 um process with Cadence’s Virtuoso simulation. According to test results, the proposed circuit has a improved transient characteristics compare with conventional LDO. The simulation results show that the transient of rising increases from –836.2uV to –123.3uV and the transient of falling decreases from 913.1uV to 715.8uV compared with conventional LDO.

Stack 기술을 이용한 높은 홀딩 전압과 향상된 감내 특성을 갖는 ESD 보호회로에 관한 연구

권상욱(Sang-wook Kwon),채희국(Hee-guk Chae),도경일(Kyoung-il Do),구용서(Yong-Seo Koo) 대한전자공학회 2018 대한전자공학회 학술대회 Vol.2018 No.11

In this paper, we propose an ESD protection circuit with high holding voltage and improved tolerance characteristics using stack technology. The stacked new ESD protection circuit has a higher tolerance characteristic than a typical LVTSCR. The simulation was performed using the TCAD simulator of the synopsys company. The single device has a holding voltage of 0V and has better robustness characteristics than LVTSCR

Push-Pull 패스 트랜지스터 구조 및 향상된 Load Transient 특성을 갖는 LDO 레귤레이터

권상욱(Sang-Wook Kwon),송보배(Bo Bae Song),구용서(Yong-Seo Koo) 한국전기전자학회 2020 전기전자학회논문지 Vol.24 No.2

본 논문에서는 Push-Pull 패스 트랜지스터 구조로 인하여 향상된 Load Transient 특성을 향상시킨 LDO(Low Drop-Out)를 제안하였다. LDO 레귤레이터 내부의 오차증폭기의 출력단과 패스 트랜지스터의 게이트단 사이에 제안된 Push-Pull 회로와 출력단에 Push-Pull 회로를 추가하여 전압 라인에 들어오는 Overshoot, Undershoot를 개선시켜 기존의 LDO 레귤레이터보다 개선된 Load Transient 특성의 델타 피크 전압 값을 갖는다. 제안하는 회로는 Cadence의 Virtuoso, Spectre 시뮬레이션을 이용하여 삼성 0.13um 공정에서 특성을 분석하였다. In this paper present a Low Drop-Out(LDO) regulator that improves load transient characteristics due to the push-pull pass transistor structure is proposed. Improved load over the existing LDO regulator by improving the overshoot and undershoot entering the voltage line by adding the proposed push-pull circuit between the output stage of the error amplifier inside the LDO regulator and the gate stage of the pass transistor and the push-pull circuit at the output stage. It has a delta voltage value of transient characteristics. The proposed LDO structure was analyzed in Samsung 0.13um process using Cadence’s Virtuoso, Spectre simulator.

전류 스위칭 회로를 이용한 빠른 과도응답특성을 갖는 Capless LDO 레귤레이터

권상욱(Sang-Wook Kwon),도경일(Kyoungil Do),서정주(Jeong-Ju Seo),구용서(Yong-Seo Koo) 대한전자공학회 2019 대한전자공학회 학술대회 Vol.2019 No.11

This paper present a capless low drop out regulator (LDO) that improves the load transient response characteristics by using a current switching circuit. A voltage regulator circuit is placed between the error amplifier and the pass transistor inside the LDO regulator to improve the current characteristics of the voltage line, The proposed fast transient LDO structure was designed by a 0.18 um process with cadence’s virtuoso simulation. according to test results, the proposed circuit has a improved transient characteristics compare with conventional LDO. the simulation results show that the transient of rising increases from 1.054 us to 118 ns and the transient of falling decreases from 12.48 us to 3.2 us compared with conventional capless LDO. this Result has improved response rate of about 78%, 40%.

N-Stack 기술이 적용된 추가적인 기생 NPN 바이폴라 트랜지스터로 인한 높은 홀딩 전압을 갖는 ESD 보호소자에 관한 연구

권상욱(Sang-Wook Kwon),서우열(U-Yeol Seo),구용서(Yong-Seo Koo) 대한전자공학회 2023 대한전자공학회 학술대회 Vol.2023 No.6

In this paper, we propose an ESD protection device with higher holding voltage characteristics than existing ESD protection devices. The proposed ESD protection device increases the holding voltage by operating an additional parasitic NPN bipolar transistor. As a result, it was confirmed that the proposed ESD protection device has a holding voltage of 5.9V. In addition, it is expected that through Stack technology, it will be possible to design ESD protection devices corresponding to the voltages required by various applications.