http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
광 도파관이 외부로 노출된 구조를 가지는 비분산적외선 이산화탄소 센서
정동건 ( Dong Geon Jung ),이준엽 ( Junyeop Lee ),도남곤 ( Nam Gon Do ),정대웅 ( Daewoong Jung ) 한국센서학회 2021 센서학회지 Vol.30 No.6
In this study, a Non-Dispersive Infrared (NDIR) Carbon Dioxide (CO<sub>2</sub>) sensor with an externally exposed optical cavity is proposed for improving sensitivity. NDIR CO<sub>2</sub> sensors with high performance must use a lamp-type infrared (IR) source with a strong IR intensity. However, a lamp-type IR source generates high thermal energy that induces thermal noise, interfering with the accuracy of the CO<sub>2</sub> concentration measure. To solve this problem, the optical cavity of the NDIR CO<sub>2</sub> sensor is exposed to quickly dissipate heat. As a result, the proposed NDIR CO<sub>2</sub> sensor has a shorter warm-up time and a higher sensitivity compared to the conventional NDIR CO<sub>2</sub> sensor.
부영양화 사전 예방을 위한 휴대용 총인 모니터링 시스템 개발
정동건 ( Dong Geon Jung ),김승덕 ( Seung Deok Kim ),권순열 ( Soon Yeol Kwon ),이재용 ( Jae Yong Lee ),김유성 ( Yu Seong Kim ),이준엽 ( Junyeop Lee ),김재건 ( Jaekeon Kim ),김세완 ( Sae-wan Kim ),공성호 ( Seong Ho Kong ),정대웅 ( D 한국센서학회 2020 센서학회지 Vol.29 No.5
In this study, a portable total-phosphorus (TP) monitoring system utilizing a photocatalytic-reaction-based pretreatment method is proposed, fabricated, and characterized. Commercial TP monitoring systems are only used in laboratories because of their complex monitoring procedure, bulk-size, and high-cost. In particular, pretreatment in commercial TP monitoring systems is performed at high temperatures (> 120 ℃) and pressure (> 1.1 kg cm<sup>-2</sup>) making it difficult to minimize the scale of the systems. The proposed TP monitoring system employs a pretreatment method with a photocatalytic reaction; thus, its size can be reduced, as photocatalytic reactions occur at room temperature and atmospheric pressure. Analytes with various TP concentrations are pretreated using the proposed portable TP monitoring system and are quantitatively measured with an LED and a photodiode.
김승덕 ( Seung Deok Kim ),정동건 ( Dong Geon Jung ),권순열 ( Soon Yeol Kwon ),최영찬 ( Young Chan Choi ),이재용 ( Jae Yong Lee ),구성모 ( Seong Mo Koo ),공성호 ( Seong Ho Kong ) 한국센서학회 2020 센서학회지 Vol.29 No.2
Total organic carbon (TOC) analysis equipment, which was previously used to prevent eutrophication in advance, is heavy, bulky, and expensive; therefore, so it is difficult to be carried and has been used as an experimental unit. In this study, a through-carbon analysis chip that integrates pretreatment through photocatalytic oxidation and carbon dioxide measurement using a pH indicator was investigated. Both the total carbon - inorganic carbon method and the nonpurgeable organic carbon (NPOC) measurement method require an acidification part for injecting an acid solution for inorganic carbon measurement and removal, an oxidation part for total carbon or NPOC oxidation and a measurement part for Carbon dioxide (CO<sub>2</sub>) measurement. Among them, the measurement of oxidation and CO<sub>2</sub> requires physical technology. The proposed TOC analysis chip decomposed into CO<sub>2</sub> as a result of the oxidizing of organic carbon using a photocatalyst, and the pH indicator that was changed by the generated CO<sub>2</sub> was optically measured. Although the area of the sample of the oxidation part and the pH indicator of the measurement part were distinguished in an enclosed space, CO<sub>2</sub> was quantified by producing an oxidation part and a measurement part that shared the same air in one chip. The proposed TOC analysis chip is less expensive and smaller, cost and size are disadvantages of existing organic carbon analysis equipment, because it does not require a separate carrier gas to transport the CO<sub>2</sub> gas in the oxidation part to the measurement part.
성병목 ( Byung Mok Sung ),정동건 ( Dong Geon Jung ),방순재 ( Soon Jae Bang ),백선민 ( Sun Min Baek ),공성호 ( Seong Ho Kong ) 한국센서학회 2015 센서학회지 Vol.24 No.4
An infrared (IR) bolometer measures the change of resistance by absorbing incident IR radiation and generates a signal as a function of the radiation intensity. Since a bolometer requires temperature stabilization and light filtering except for the infrared rays, it is essential for the device to be packaged meeting conditions that above mentioned. Minimization of heat loss is needed in order to stabilize temperature of bolometer. Heat loss by conduction or convection requires a medium, so the heat loss will be minimized if the medium is a vacuum. Therefore, vacuum packaging for bolometer is necessary. Another important element in bolometer packaging is germanium (Ge) window, which transmits IR radiation to heat the bolometer. To ensure a complete transmittance of IR light, anti-reflection (AR) coatings are deposited on both sides of the window. Although the transmittance of Ge window is high for IR rays, it is difficult to use frequently in low-price IR bolometer because of its high price. In this paper, we fabricated IR window by utilizing silicon (Si) substrate instead of Ge in order to reduce the cost of bolometer packaging. To enhance the IR transmittance through Si substrate, it is textured using Reactive Ion Etching (RIE). The texturing process of Si substrate is performed along with the change of experimental conditions such as gas ratio, pressure, etching time and RF power.
TiO<sub>2</sub>/GOD 혼합물 기반의 글루코스 바이오 센서의 제작과 표면 처리를 통한 감도개선
이준엽 ( Junyeop Lee ),정동건 ( Dong Geon Jung ),이재용 ( Jae Yong Lee ),김재건 ( Jae Keon Kim ),정대웅 ( Daewoong Jung ),공성호 ( Seong Ho Kong ) 한국센서학회 2018 센서학회지 Vol.27 No.3
In this paper, the TiO<sub>2</sub>/glucose oxidase (GOD) mixture has synthesized through simple and low-cost fabrication methods. The physical properties of the mixture were proved using an FT-IR/NIR spectrometer, an X-Ray diffractometer, and a Raman spectrometer. GOD maintained its bioactivity during all fabrication process. The current characteristics of the glucose biosensor were proportional to the glucose concentration and effective surface area of square pyramid on a silicon substrate. The maximum current change was measured in a pH 7.0 buffer solution. The simple and low-cost fabrication process and surface treatment can be used widely in previous research for improvements in effective surface area.
투명 유연 박막 트랜지스터의 구현을 위한 열처리된 산화아연 박막의 전사방법 개발
권순열 ( Soon Yeol Kwon ),정동건 ( Dong Geon Jung ),최영찬 ( Young Chan Choi ),이재용 ( Jae Yong Lee ),공성호 ( Seong Ho Kong ) 한국센서학회 2018 센서학회지 Vol.27 No.3
Zinc oxide (ZnO) thin films have the advantages of growing at a low temperature and obtaining high charge mobility (carrier mobility) [1]. Furthermore, the zinc oxide thin film can be used to control application resistance depending on its oxygen content. ZnO has the desired physical properties, a transparent nature, with a flexible display that makes it ideal for use as a thin-film transistor. Though these transparent flexible thin-film transistors can be manufactured in various manners, manufacturing large-area transistors using a solution process is easier owing to the low cost and flexible substrate. The advantage of being able to process at low temperatures has been attracting attention as a preferred method. However, in the case of a thin-film transistor fabricated through a solution process, it is reported that charge mobility is lower. To improve upon this, a method of improving the crystallinity through heat treatment and increasing electron mobility has been reported. However, as the heat treatment temperature is relatively high at 500°C, an application where a flexible substrate is absent would be more suitable.
다양한 동작신호의 사용에 따른 연동형 마이크로 펌프의 성능 향상
홍표환 ( Pyo Hwan Hong ),정동건 ( Dong Geon Jung ),표대승 ( Dae Seong Pyo ),이종현 ( Jong Hyun Lee ),조찬섭 ( Chan Seob Cho ),김봉환 ( Bong Hwan Kim ) 한국센서학회 2013 센서학회지 Vol.22 No.6
This paper described the development of electrostatically driven peristaltic micropump. The proposed micropump consists of a flexible membrane and a single chamber which electrodes are inserted. The single chamber is divided into smaller cells by the electrodes. The fabricated micropump was operated with four electrodes in the membrane and a various phase sequencing actuation. We studied the changes in the flow rate corresponding to the actuating signal applied to the micropump under the zero hydraulic pressure difference between lnlet port and outlet port. The pump was operated from 60 to 130 V. Whereas the maximum flow rate in basic actuating signal is about 83 μ1/min at 15 Hz, the maximum flow rate in optimized actuating signal is about 114 μl/min at 10 Hz.
수생태계 부영양화 분석을 위한 비색법 기반의 광학식 센서 신호처리회로(ROIC)구현
구성모 ( Seong Mo Koo ),정동건 ( Dong Geon Jung ),최영찬 ( Young Chan Choi ),김경규 ( Kyung-kyoo Kim ),공성호 ( Seong Ho Kong ) 한국센서학회 2020 센서학회지 Vol.29 No.4
In this study, a read-out integrated circuit (ROIC) that can be applied to a colorimetry-based optical sensor for analyzing total phosphorus and total nitrogen was developed and characterized. The proposed ROIC minimizes the effect on temperature fluctuation, improves sensitivity, and extends the dynamic range by utilizing a dual optical path and feedback control circuit. Using a dual optical path makes it possible to calibrate the output signal of the optical sensor automatically, along with the temperature fluctuation. The calibrated voltage is fed back into the measurement stage; thus, the output current of the measurement is adaptively controlled. As a result, the sensitivity and dynamic range of the proposed ROIC are improved. Finally, a total-phosphorus analysis was conducted by utilizing the ROIC. The ROIC was found to operate stably over a wide temperature range.
이산화탄소 감지를 위한 4.26 μm 필터용 poly-Si/SiO<sub>2</sub> 다층 박막 기반의 패브리 페로-필터
도남곤 ( Nam Gon Do ),이준엽 ( Junyeop Lee ),정동건 ( Dong Geon Jung ),공성호 ( Seong Ho Kong ),정대웅 ( Daewoong Jung ) 한국센서학회 2021 센서학회지 Vol.30 No.1
In this study, the relationship between the transmitted light intensity and full-width-at-half-maximum (FWHM) of a Fabry-Perot filter was investigated. The measured refractive indices and absorption coefficients of the fabricated thin films were applied to the Fabry-Perot filter via simulations using optical software. Although considerable research has been conducted on Fabry-Perot filters, this study focused on the usefulness of 4.26-μm infrared filtering in carbon dioxide detection. Optical analysis was performed considering the effects of the thickness, refractive indices, and number of thin films in a distributed Bragg reflector. Ultimately, a clear trade-off relationship was observed wherein the transmitted light intensity decreased as the number of multilayers increased; however, the FWHM was observed to be narrower.
분산 반사경 기반 패브리-페로 필터를 이용한 비분산적외선 CO<sub>2</sub> 센서의 감지 특성
도남곤 ( Nam Gon Do ),이준엽 ( Junyeop Lee ),정동건 ( Dong Geon Jung ),공성호 ( Seong Ho Kong ),정대웅 ( Daewoong Jung ) 한국센서학회 2021 센서학회지 Vol.30 No.6
Non-dispersive infrared (NDIR) gas sensors typically use an optical filter that transmits a discriminating 4.26 μm wavelength band to measure carbon dioxide (CO2), as CO2 absorbs 4.26 μm infrared. The filter performance depends on the transmittance and full width at half maximum (FWHM). This paper presents the fabrication, sensitivity, and selectivity characteristics of a distributed Bragg reflector (DBR)-based Fabry-Perot filter with a simple structure for CO2 detection. Each Ge and SiO2 films were prepared using the RF magnetron sputtering technique. The transmittance characteristics were measured using Fourier-transform infrared spectroscopy (FT-IR). The fabricated filter had a peak transmittance of 59.1% at 4.26 μm and a FWHM of 158 nm. In addition, sensitivity and selectivity experiments were conducted by mounting the sapphire substrate and the fabricated filter on an NDIR CO2 sensor measurement system. When measuring the sensitivity, the concentration of CO2 was observed in the range of 0-10000 ppm, and the selectivity was measured for environmental gases of 1000 ppm. The fabricated filter showed lower sensitivity to CO2 but showed higher selectivity with other gases.