연기/CO 및 연기/열 복합형 IoT 멀티 화재 감지기의 화재감지실험 연구

손근식,소수현,Son, Geun­Sik,So, Soo­Hyun 한국재난정보학회 2021 한국재난정보학회 논문집 Vol.17 No.2

Purpose: The purpose of this study is to develop IoT multi-fire detectors combined smoke/carbon monoxide/heat and wireless IoT communication and to confirm the detect performance by smoke generator fire test and cotton wicks fire test. Method: The IoT multi-fire detector combined smoke and CO and combined smoke and heat were experimented the detect performance by smoke generator test and fire test of cotton wicks. And the case of fire alarm was checked. Result: The IoT multi-fire detector combined smoke and CO rung the alarm at the fire test of cotton wicks, did not ring the alarm at the smoke generator test. In comparison, the IoT multi-fire detector combined smoke and heat did not ring the alarm both at the smoke generator test and the fire test of cotton wicks. Conclusion: The IoT multi-fire detector combined smoke and CO detected the only smoke including the carbon monoxide and the IoT multi-fire detector combined smoke and heat did not ring the alarm for lack of heat. As a result, when the developed IoT multi-fire detector was detected the signal more than the set point, the fire alarm was sounded through cotton wicks fire test and smoke generator. 연구목적: 연기/CO/열 복합형 화재감지기와 무선 IoT통신을 결합한 IoT 멀티화재감지기를 개발하고 화재감지 실험을 통하여 연기/CO/열 복합형 IoT 멀티화재감지기의 화재감지성능을 확인하는 것을 목적으로 한다. 연구방법: 연기/CO 복합형 과 연기/열 복합형의 IoT 멀티화재감지기를 연기발생기와 면 심지 연소를 통하여 화재감지성능을 실험하였으며, 화제 신호를 발하는 기준을 확인하였다. 연구결과: 연기/CO 복합형 IoT 멀티 화재감지기는 면심지 연소 실험에서 화재를 감지하였으나 연기발생기 실험에서는 화재를 감지하지 않았다. 반면 연기/열 복합형 IoT 멀티 화재감지기는 두 실험 모두 화재를 감지하지 않았다. 결론: 연기/CO 복합형 IoT 멀티화재감지기는 CO가 포함된 연기만을 감지하였으며, 연기/열 복합형 IoT 멀티 화재감지기는 열의 부족에 의해 화재를 잠지하지 않았다. 이와 같은 결과로 개발된 IoT 멀티 화재감지기는 면심지 연소 실험과 연기발생기 실험을 통해 2가지 센서의 기준값 이상 신호를 검출하여야 화재 신호를 발한다는 것을 확인하였다.

편광 간섭을 이용한 광도파로 기반의 표면 굴절률 센서

손근식,권순우,김우경,양우석,이형만,이한영,이성동,이상신,Son, Geun-Sik,Kwon, Soon-Woo,Kim, Woo-Kyung,Yang, Woo-Seok,Lee, Hyung-Man,Lee, Han-Young,Lee, Sung-Dong,Lee, Sang-Shin 한국광학회 2008 한국광학회지 Vol.19 No.3

본 논문에서는 폴리머 광도파로 상부에 $TiO_2$(Titanium dioxide)박막이 증착된 굴절률 센서를 구현하였다. 제작된 센서를 이용하여 글리세롤의 굴절률 변화에 따른 출력광의 편광 간섭 변화를 측정하였다. 또한 박막 두께에 따른 편광 간섭의 민감도 변화를 확인하고, 수치해석 결과와 비교하였다. 특히 $TiO_2$가 20 nm 증착된 광도파로에서 $2{\pi}$의 위상차를 갖는 굴절률 변화는 $1.8{\times}10^{-3}$이다. A novel refractive index sensor, which consists of polymer channel waveguide overlaid with $TiO_2$ thin film, is demonstrated. To evaluate the fabricated sensor, we measured the polarimetric interference induced by concentration change of injected glycerol solution. Our experimental results show that thicker $TiO_2$ film improves the sensitivity of the polarimetric interferometer. For the fabricated waveguide with a 20 nm thick $TiO_2$ film, the measured index change to lead phase variation of $2{\pi}$ is $1.8{\times}10^{-3}$.

압전 폴리머 필름을 이용한 소방관의 호흡률 모니터링

손근식(Geun-Sik Son),한상희(Sang-Hee Han),차병준(Byung-Jun Cha),맹준호(Jun-Ho Maeng),신현준(Hyun-Jun Shin),우덕하(Deok-Ha Woo),장재성(Jaesung Jang),이상엽(Sang-Youp Lee) 대한기계학회 2013 대한기계학회 춘추학술대회 Vol.2013 No.12

Firefighters are always exposed to physically and mentally stressful environments resulting in three times higher death rate than any other occupations. Physiological signal monitoring for firefighters is critical and essential to protect firefighters’ lives because more than half of deaths are attributed to stress or overexertion including heart attacks, cerebrovascular events (stroke) or other types of cardio-respiratory system collapse. In current study, we have demonstrated that PVDF wearable sensor can monitor respiration rate successfully. The principle is based on the piezoelectric sensing mechanism to detect the periodical deformations on the chest wall of human body during respirations. For a fabricated sensor involving a 28um thick PVDF film, measured to respiration rate by making the simulator. Respiration simulator at 10 to 90 bpm can make respiration rate. Small changes in the electrical signal output to be punched in the PVDF film. As a result, changes in the length of 1mm were possible to output an electrical signal. PVDF film banding worn on the human body due to aerobic exercise respiration rate was measured. As a whole, this study has developed a PVDF based sensor which was capable of monitoring the respiration rate with high sensitivity. Other distinctive features include its small size, light weight, ease of use and low cost.

고온열전모듈용 금속유리계 페이스트 연구

서승호,손근식,서강현,최순목,Seo, Seung-Ho,Son, Geun Sik,Seo, Kang Hyun,Choi, Soon-Mok 한국전기전자재료학회 2018 전기전자재료학회논문지 Vol.31 No.4

We researched about a bulk metallic glass system as an additive to an Ag paste for high temperature thermoelectric modules. Bulk metallic glass (BMG) ribbons were produced by using a rapid solidification process (RSP) under a cooling rate condition higher than $10^{\circ}C/sec$. We investigated BMG characteristics of the ribbons by means of x-ray diffraction (XRD) and differential scanning calorimetry (DSC) in order to evaluate the glass transition temperature ($T_g$) and the recrystallization temperature ($T_x$) lower than $400^{\circ}C$. A milling process was also developed to apply the BMG ribbons to a commercial Al paste as an additive for lower sintering temperature.

복수 개의 광파장에 대한 상대적 흡광 특성을 이용한 글루코스 농도 측정

김기도,손근식,임성수,이상신,Kim, Ki-Do,Son, Geun-Sik,Lim, Seong-Soo,Lee, Sang-Shin 한국광학회 2008 한국광학회지 Vol.19 No.6

본 논문에서는 복수 개의 측정 광파장 대역에서의 글루코스 수용액의 상대적인 흡광 특성을 이용한 글루코스 농도 예측 방법을 제안하고 검증하였다. 각 측정 파장에서의 상대적인 흡광도는 기준 파장에서의 흡광도를 기준하여 얻어진다. 선정된 기준 파장(1310 nm)과 네 개의 측정 파장(1064, 1550, 1685, 1798 nm) 대역에서는 글루코스에 대한 흡광도가 서로 반대의 부호를 갖도록 하였으며, 이 특성은 측정 정확도를 높이는데 도움이 된다. 최종적인 글루코스 수용액의 예측 농도는 각 측정 파장에서 얻어진 예측 값의 평균으로 결정된다. 5 mm의 광경로와 $0{\sim}1000mg/dL$ 농도 범위에서 실제로 측정된 글루코스의 흡광도를 살펴보면, 기준 파장 1310 nm에서는 $-1.42{\times}10^{-6}\;AU$/(mg/dL), 측정 파장 1685 nm에서는 $+8.12{\times}10^{-6}\;AU$/(mg/dL)로 최대였다. 그리고 제안된 방법을 이용하여 글루코스 용액의 농도를 예측할 경우 얻어진 표준예측오차(SEP: standard error of prediction)는 ${\sim}28\;mg/dL$였다. 또한, 온도와 지방층이 글루코스 농도 측정에 미치는 영향을 조사하였다. 먼저 $26{\sim}40^{\circ}C$ 온도 범위에서 측정된 흡수량 변화율은 기준 파장 1310 nm에서 $-9.1{\times}10^{-5}\;AU/^{\circ}C$였고, 측정 파장 1550 nm에서 $-2.08{\times}10^{-2}\;AU/^{\circ}C$였다. 그리고 글루코스 수용액에 존재하는 지방층 두께에 따른 흡수량 변화율은 1685 nm 파장 대역에서 +1.093 AU/mm로 측정되었다. A scheme for predicting the concentration of a glucose solution based on its relative optical absorbance at multiple probe wavelengths was proposed and verified. The relative absorbance at each of the probe wavelength was obtained with respect to the absorbance at a reference wavelength. The single reference wavelength (1310 nm) and a group of four different probe wavelengths (1064, 1550, 1685, 1798 nm) were selected to exhibit the glucose absorbance with opposite signs, thereby enhancing the accuracy of the prediction. The final glucose concentration was estimated by taking the average of the predicted values provided by the four probe wavelengths. The absorbance of the glucose solution for the path length of 5 mm was $-1.42{\times}10^{-6}\;AU$/(mg/dL) at the reference wavelength of 1310 nm and peaked at $+8.12{\times}10^{-6}\;AU$/(mg/dL) at 1685 nm. The concentration of the glucose solution was decently predicted by means of the proposed scheme with the standard error of prediction of ${\sim}28\;mg/dL$. In addition, the influence of the ambient temperature and the fat thickness upon the prediction of the glucose concentration was examined. The absorption change with the temperature was $-9.1{\times}10^{-5}\;AU/^{\circ}C$ in the temperature range of $26{\sim}40^{\circ}C$ at the reference wavelength, and $-2.08{\times}10^{-2}\;AU/^{\circ}C$ at 1550 nm. And the absorption change with respect to the fat thickness was +1.093 AU/mm at the probe wavelength of 1685 nm.

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.

피난 효율 향상을 위한 제연스프링클러헤드 개발에 대한 연구

이준혁(Joon Hyuk Lee),노호성(Ho Seong Rho),손근식(Geun Sik Son) 한국화재소방학회 2023 한국화재소방학회 학술대회 논문집 Vol.2023 No.1