수직형 폴리머 마이크로링 공진기 기반의 글루코스 바이오 센서

김건덕,손근식,이학순,김기도,이상신,Kim, Gun-Duk,Son, Keun-Sik,Lee, Hak-Soon,Kim, Ki-Do,Lee, Sang-Shin 한국광학회 2008 한국광학회지 Vol.19 No.2

본 논문에서는 굴절률 감지 방식의 수직 결합형 폴리머 마이크로링 공진기 기반 글루코스 바이오 센서를 제안하고 구현하였다. 이 센서에서 상부 클래딩 역할을 하는 글루코스 분석 대상물의 농도 변화는 링 공진기의 공진파장 이동을 측정함으로써 얻어진다. 특히, 센서의 감도를 향상시키기 위해 다음과 같은 방법을 사용하였다. 첫째로, 분석 대상물에 근접한 유효굴절률을 갖는 폴리머 도파로 구조를 공진기 센서에 도입하였다. 둘째로, 분석 물질의 접촉면적을 확대하기 위해 측면 클래딩층이 충분히 식각된 pedestal 링 도파로 구조를 사용하였다. 제안된 공진기 센서는 빔전파 방법을 사용하여 설계하고 분석하였다. 사용된 코어 및 클래딩용 폴리머의 굴절률은 각각 1.430과 1.375였으며, 링 반경은 $400\;{\mu}m$였다. 이 때 얻어진 도파로의 유효굴절률은 ${\sim}1.390$였으며 글루코스 수용액의 굴절률 1.333와 매우 근접하였다. 제작된 소자의 기본적인 전달특성은 FSR(free spectral range) 0.66 nm, 대역폭 ${\sim}0.15\;nm$, Q 값 10,000 이었다. 1550 nm 광파장 대역에서 얻어진 측정 결과를 살펴보면, 센서 감도는 ${\sim}0.28\;pm$/(mg/dL)였으며, 이에 따른 굴절률 변화 감도는 ${\sim}200\;nm/RIU$였다. A refractometric glucose biosensor incorporating a vertically coupled microring resonator in polymers was proposed and realized. The ring was covered with a target analyte of glucose solution with a certain concentration, so that its effective refractive index could be altered and, as a result, the resonance wavelength of the sensor was shifted. Therefore the concentration of the glucose solution can be estimated by observing the shift in the resonance wavelength. Two schemes were exploited for enhancing the sensitivity of the sensor. First, the effective refractive index of the polymeric waveguide used for the resonator sensor was adjusted to approach that of the target analyte as best as possible. Second, the ring waveguide, which serves as a crucial sensing part, was appropriately over-etched to enlarge its contact area with the analyte. The proposed resonator sensor was designed with the beam propagation method. The refractive indices of the core and cladding polymer involved were 1.430 and 1.375 respectively, leading to the waveguide's effective refractive index of ${\sim}1.390$, which is faiirly close to that of the glucose solution of ${\sim}1.333$. The prepared ring resonator with the $400-{\mu}m$ radius exhibited the free spectral range of 0.66 nm, the bandwidth of 0.15 nm, and the quality factor of 10,000. For the sensor operating at 1,550 nm wavelength, the achieved sensitivity was as great as 0.28 pm/(mg/dL), which is equivalent to 200 nm/RIU.

폴리머 광공진기 라우터 기반의 4채널 선택 포토닉 마이크로웨이브 대역통과 필터

김건덕,어윤성,이상신,Kim, Gun-Duk,Eo, Yun-Sung,Lee, Sang-Shin 한국광학회 2008 한국광학회지 Vol.19 No.3

본 논문에서는 $1{\times}4$ 스위치와 서로 다른 FSR(free spectral ranges)을 갖는 마이크로링 공진기 배열을 결합하여 구현된 광공진기 라우터를 기반으로 하는 집적광학 방식의 4채널 선택 마이크로웨이브(microwave: MW) 필터를 제안하고 구현하였다. 중심 주파수는 링 공진기의 반지름에 따른 FSR에 의해 결정되며, 이를 통해 얻어지는 10 GHz, 16 GHz, 18 GHz, 20 GHz로 구성된 4개의 채널은 광스위치에 제어 전압을 인가하여 개별적으로 선택할 수 있었다. A four-channel selective microwave filter was demonstrated incorporating an optical resonator router, which is constructed by integrating a $1{\times}4$ space switch with an arrayed ring filters featuring different free spectral ranges. The center frequency of each channel was determined by the FSR of the corresponding ring resonator, and the four channels centered at 10 GHz, 16 GHz, 18 GHz and 20 GHz were individually selected to provide a bandpass filtering via the control voltage applied to the switched resonator.

폴리머 링 공진기 기반의 스위치를 이용한 집적광학 채널 선택 마이크로웨이브 대역통과 필터

김건덕,이상신,Kim, Gun-Duk,Lee, Sang-Shin 한국광학회 2007 한국광학회지 Vol.18 No.1

A reconfigurable photonic microwave (MW) channel selective filter was demonstrated incorporating a $1{\times}2$ switch based on two tunable polymeric resonators with different free spectral ranges. Each resonator, consisting of two cascaded rings with an electrode formed on one of them, plays a role as an on/off switch through the thermooptic effect. The optical signal carrying the MW signal is routed to either port of the switch and detected to show the filtered output at the frequency determined by the free spectral range of the corresponding resonator. When the channel centered at 10 GHz was chosen, the extinction ratio was ${\sim}30dB$, the bandwidth 1 GHz, and the electrical power consumption 4.1 mW. For the other channel located at 20 GHz, we have achieved the extinction ratio of ${\sim}30dB$, the bandwidth of 2 GHz, and the required power of 8.0 mW. Finally the crosstalk between the selected and blocked channels was higher than 24 dB. 본 논문에서는 서로 다른 FSR (free spectral range)을 갖는 두 개의 가변 (tunable) 폴리머 링 공진기 기반의 $1{\times}2$ 스위치를 이용하여 광학적 방식의 채널 선택이 가능한 재구성형 (reconfigurable) 마이크로웨이브 (microwave: MW) 필터를 제안하고 구현하였다. 각 링 공진기는 두 개의 링이 연결되어 있으며 한 개의 링 위에 전극이 형성되어 있으며, 이 전극에 전압을 인가함으로써 열광학효과를 통해 On/Off 스위치로서 동작된다. 입력 MW 신호에 의해서 변조된 광신호를 이 스위치를 통해 특정 포트로 라우팅(routing)하고 광검출기를 통해 복원함으로써 두 개의 채널이 선택되는 MW 대역통과 필터 특성을 얻었다. 중심주파수가 10 GHz인 채널 I 이 선택된 경우, 소멸비는 ${\sim}30dB$, 대역폭은 1 GHz, Q값은 10, 최대 소비전력은 4.1 mW였다. 그리고 중심주파수가 20 GHz인 채널II가 선택된 경우에는 소멸비는 ${\sim}30dB$, 대역폭은 2 GHz, Q값은 10, 최대 소비전력은 8 mW였으며, 각 채널 간의 격리도는 24 dB 이상이었다.

전기적으로 가변되는 전달특성을 갖는 폴리머 링 광공진기를 이용한 마이크로웨이브 대역통과 필터

김건덕,이상신,Kim, Gun-Duk,Lee, Sang-Shin 한국광학회 2006 한국광학회지 Vol.17 No.5

본 논문에서는 폴리머 링 광공진기를 이용하여 집적광학형 K-band용 마이크로웨이브 대역통과 필터를 제안하고 구현하였다. 특히, 열광학 효과를 이용하여 광공진기의 공진파장을 변화시킴으로써 대역통과 필터의 전달특성을 전기적으로 조절하였다. 측정된 필터의 중심주파수는 20 GHz, 소멸비는 약 15 dB, 3 dB 대역폭은 2 GHz, 그리고 Q값은 10이었다. 마이크로웨이브 필터에서 중심주파수의 출력특성을 27 dB범위 내에서 ${\sim}6.7dB/mW$로 조절할 수 있었다. 전기적으로 조절되는 전달특성을 갖는 이 필터는 마이크로웨이브스위치 등으로 응용할 수 있을 것으로 기대된다. An integrated photonic K-band microwave bandpass filter has been proposed and demonstrated by incorporating a polymeric ring resonator. Its transfer characteristics were adjusted by shilling the resonance wavelength of the ring resonator via the thermooptic effect. The achieved performance of the filter includes the center frequency of 20 GHz, the attenuation of ${\sim}15dB$, the bandwidth of 2 GHz, and the corresponding quality factor of 10. The microwave output power within the passband of the device was adjusted at the rate of about 6.7 dB/mW in the range of 27 dB. This kind of device with electrically controllable transfer characteristics can be applied to implement microwave switches and other devices.

원가절감형 면발광 개발

김건덕(Kim, Gun-Duk),이혁민(Lee, Hyuk-Min),김정영(Kim, Jung Young) 한국자동차공학회 2017 한국자동차공학회 학술대회 및 전시회 Vol.2017 No.11

수직 결합형 폴리머 마이크로디스크 공진기를 이용한 광학적 글루코스 센서

金乾德(Gun-Duk Kim),孫根植(Geun-Sik Son),李鶴淳(Hak-Soon Lee),金基道(K-Do Kim),李相信(Sang-Shin Lee) 대한전기학회 2008 전기학회논문지 Vol.57 No.8

A glucose biosensor using a microdisk resonator in polymeric waveguides was developed by observing either the shift in the resonant wavelength or the variation in the optical power. The deformation in the transfer curve of the vertically coupled resonator sensor resulting from the variation in the disk-to-ring coupling, which was incurred by the application of the target analyte, was suppressed. And the refractive index of the polymeric waveguide was devised to closely follow that of the analyte itself for enhancing the sensitivity of the sensor. The sensitivity and measurement range were observed to be respectively 0.14 pm/(㎎/dL) and 1500 ㎎/dL (theoretically up to 4700 ㎎/dL), for the wavelength shift method and 0.04 ㏈/(㎎/dL) and 140 ㎎/dL the power variation scheme.

제련소 주변토양 중금속 존재형태

우상덕,김건하,김영진,남경필,Woo, Sang-Duck,Kim, Geon-Ha,Kim, Young-Jin,Nam, Kyoung-Phile 한국지하수토양환경학회 2010 지하수토양환경 Vol.15 No.5

Heavy metals in soils exist in various forms dependent upon surrounding conditions. As the Janghang smelter area is of concern for its high elevated heavy metal concentrations, Korean government decided to remediate the area. Main objectives of this research were; to analyze heavy metal concentrations and their existing forms in the vicinity of the smelter; and to understand differences made by analysis techniques of heavy metals. Top soils of rice field, crop field, bare field, and forestry in the area were sampled and analyzed for their physicochemical characteristics. Concentrations of Cu, Cd, Pb, and As were analyzed with two pretreatment techniques adopted using 0.1 N HCl and aqua regia. To analyze existing forms of heavy metals, Tessier's schemes for sequential extraction technique were adopted. Exchangeable fraction and carbonate bound fraction of heavy metals may pose potential threat to environment and were in the order of Pb > As > Cu > Cd. If assessing mobile fraction of heavy metals by land uses, the order was forestry > bare land > crop field > rice field. When analyzed using Tessier's scheme, high ratio of residual fractions to total arsenic concentration should be considered for remediation design of the area.

OneSAF 모델을 위한 명중률 데이터 변환 방법

김건인,강태호,서우덕,변재정,Kim, Gun In,Kang, Tae Ho,Seo, Woo Duck,Pyun, Jae Jung 한국시뮬레이션학회 2020 한국시뮬레이션학회 논문지 Vol.29 No.3

OneSAF 모델의 활용이 본격화될 것으로 판단되는 현재 시점에서 가장 중요한 요소는 입력 데이터의 확보이다. 특히 모델 운용자들이 가장 결정하기 어려운 입력 데이터는 명중률과 살상률 데이터이다. 이러한 데이터들은 개발시험평가와 운용시험평가 기간 중에 실시되는 실사격 실험들을 통하여 결정되므로 많은 자원과 시간이 소요된다. 따라서 상대적으로 효율적이면서 비교적 정확한 방법들이 필요하다. 본 논문에서는 명중률 데이터를 확보할 수 있는 가능한 방안들을 검토하고, 방안별로 어떻게 데이터를 산출할 것인가에 대한 방법론을 소개하였다. 먼저 JMEM 도구들을 사용하여 산출된 결과로부터 OneSAF 모델의 명중률 데이터로 변환하기 위하여 필요한 방법을 제시하였다. 다음은 기존의 분석용 모델인 AWAM 모델에 입력 데이터로 존재하는 %로 표시된 명중률 데이터를 오차(mil)형태로 변환하는 방법인 오차요소법을 적용할 수 있음을 보였다. 더불어 소개된 오차요소법을 사용하여 명중률을 산출한 결과를 수행하였다. 오차요소법을 사용하여 공개된 사진 자료로부터 투사면적을 계산하여 보다 정확한 명중률을 계산하였다. 최종적으로 정확한 명중률 산출의 중요성을 명중률이 전투효과에 미치는 민감도 분석을 실시하여 입증하였다. 본 논문에서는 명중률 데이터 결정의 중요성과 꾸준한 명중률 데이터의 수집 및 분석으로 M&S 체계의 신뢰성이 향상되어야 하는 것을 강조하였다. To use the OneSAF model for the analysis of Defence M&S, the most critical factor is the acquisition of input data. The model user is hard to determine the input data such as the probability of hit(P_h) and the probability of kill(P_k). These data can be obtained directly by live fire during the development test and the operational test. Therefore, this needs more time and resources to get the P_h and P_k. In this paper, we reviewed possible ways to obtain the P_h and P_k. We introduced several data producing methodologies. In particular, the error budget method was presented to convert the P_h(%) data of AWAM model to the error(mil) data of OneSAF model. Also, the conversion method which can get the adjusted results from the JMEM is introduced. The probability of a hit was calculated based on the error budget method in order to prove the usefulness of the given method. More accurate data were obtained when the error budget method and the projected area from the published photo were used simultaneously. The importance of the P_h calculation was demonstrated by sensitivity analysis of the P_h on combat effectiveness. This paper emphasizes the importance of determining the P_h data and improving the reliability of the M&S system though steady collection and analysis of the P_h data.

공압실린더의 위치제어

서정덕(Jung-Duk Seo),이성구(Seong-Ku Lee),김건회(Gun-hoi Kim) 한국기계가공학회 2006 한국기계가공학회 춘추계학술대회 논문집 Vol.2006 No.-

The hydraulic/pneumatic pressure products are applied widely in current industrial area such as in the automation of products assembly, automation of equipment assembly, high-tech machine tool, aircraft, and train, and as the industry development is on progress, the development of the hydraulic/pneumatic pressure products is necessary and it is required in every industrial area. This research developed a position control system of the pneumatic cylinder using a pneumatic cylinder, four two-port valves, two three-port valves, two pressure valve, a check valve, two proximity sensors, and a program logic controller (PLC) to minimize the allowable error on the position control of pneumatic cylinder system and to develop a pneumatic cylinder valve system for further study. The maximum air pressure used for the position control test was 5 ㎏/cm2 and the displacement accuracy of the pneumatic cylinder was measured using a dial gauge. The supply and discharge air pressure and the length of the stroke of the pneumatic cylinder were controlled and set before experiment. The test of the position control of the pneumatic cylinder was carried out 50 times and replicated three times at each condition of the supply and discharge air pressure (2.5/3.5, 3.0/4.0, 3.5/4.5, and 4.0/5.0 ㎏/cm2) and selected stroke length of the pneumatic cylinder. The accuracy of the position control of the pneumatic cylinder increased as the supply and discharge air pressure increased at the stroke length was fixed as 133 ㎜, and increased as the stroke length increased with the fixed supply and discharge air pressure of 3.5/4.5 ㎏/cm2 of the pneumatic cylinder. The most accurate position control of the pneumatic cylinder (i.e., standard deviation of 0.01 ㎜) was obtained at the supply and discharge air pressure of 4.0/5.0 ㎏/cm2 and the stroke length of 170 and 190 ㎜.

연료전지 성능 개선 및 제어에 대한 연구

김건회(Gun-Hoi Kim),최승훈(Seung-Hun Choi),서정덕(Jung-Duck So) 한국기계가공학회 2007 한국기계가공학회 춘추계학술대회 논문집 Vol.2007 No.-

In developing new generation vehicles, the fuel cell hybrid vehicle has become more important as environmental standards become more stringent. This paper details the Fuel Cell Hybrid Radio Control Car (FCHRC) with proton exchange membrane fuel cell stack(75×55×65㎜, 6V, 5A) and a secondary battery(7.4V, 2A) charged up by a solar cell(61㎜ x 110㎜, 1.7V, 450㎃). The design work of the FCHRC was made progress by CATIA modeling & assembling before manufacturing it. In this paper, we will focus on the automatic conversion of a power source between the PEMFC and the secondary battery, and finding the optimum conditions (temperature, humidity, airflow rate and hydrogen pressure) through thousands of performance tests in the humidity-temperature program controller. Included are diagrams of the dynamo, fitting the model for the performance test, that we constructed specifically for this research, to turn out the hybrid control system having the efficiently automatic conversion in the different modes (accelerated motion, uniformly accelerated motion, steeply accelerated motion, decelerated motion). The purpose is that the models and data from the experiments we conducted will contribute to the ongoing development of the fuel cell hybrid car.