• Bulletin of the Korean Chemical Society
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• 제25권8호
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• pp.1151-1155
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• 2004

The chemosenssor that consists of [$Zn_2$(1,3-bis[bis(2-pyridylmethyl)aminomethyl]benzene)]$^{4+}$ (receptor) and pyrecatechol violet (signaling unit) detects with naked eyes di- and tri-phosphates conjugated to nucleosides or in free forms. The blue color of the aqueous solution (pH 7.0) of the sensor turns to yellow upon exposing to the analytes.

• 센서학회지
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• 제10권6호
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• pp.317-327
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• 2001

본 논문에서는 시료가 갖는 pH값의 2차원 분포를 효과적으로 측정하기 위하여, 회전 격자를 이용한 변조 광을 LAPS에 주사함으로써 PH이미지를 검출하는 방법을 제안하였다. 이는 회전 격자를 이용하여 각 픽셀별로 다른 주파수로 변조된 광을 조사하고 이에 따른 광 전류의 주파수 성분별 진폭을 계산함으로써 한 행의 신호 성분을 동시에 측정할 수 있다. 제안된 검출방법을 실험하기 위하여 LAPS의 특성을 고려한 회전격자를 설계 제작하고 제작된 회전 격자와 패턴 영상을 이용한 주파수성분 분석에 의해 이미지를 검출하였다. 실험 결과로부터 회전 격자를 이용한 제안된 검출 방식이 약22-24dB의 PSNR을 가지는 $30{\times}30$화소의 이미지를 기존의 방식보다 30배 빨리 측정할 수 있음을 확인하였다.

• 대한화학회지
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• 제32권4호
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• pp.333-341
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• 1988

Cytosine에 대한 bio-electrode는 $NH_3$ 기체감응기에 Proteus mirabilis 와 Citrobacter freundii 박테리아를 고정하여 조립하였다. cytosine deaminase를 포함하는 박테리아는 cytosine 1분자를 $NH_3$ 1분자로 전환시킨다. Proteus mirabilis 박테리아 전극의 감응은 0.2M phosphate 완충용액, pH 8.4에서 $1.0{\times}10^{-3}\;-\;7.0{\times}10^{-3}$M직선범위와 45-48 mV/decade의 감응기울기를 가진다. Citrobacter freundii박테리아 전극의 감응은 0.05M phosphate완충용액, pH 7.6에서 $7.0{\times}10^{-5}\;-\;7.0{\times}10^{-3}$M 직선범위와 48 mV/decade의 감응기울기를 가진다. 이 전극을 pH, 온도, 완충용액, 박테리아의 양, 방해물질, 무기염류의 영향과 전극의 수명을 조사하였다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 봄 학술발표회 논문집
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• pp.273-280
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• 2000

In recent years there has been a steady increase in geoenvironmental engineering projects where geotechnical engineering has been combined with environmental concerns. Many of these projects involve some investigation of contaminant in the ground. There are many techniques such as geophysical, drilling, sampling, md pushing techniques for investigation of contaminated ground. The most rapidly developing site characterization techniques for geoenvironmental purposes involve direct push technology, that is, penetration tests. The purpose of this study investigated underground oil storage tanks(USTs) using the envi-cone penetrometer system. The electrical resistivity sensor, pH sensor, ORP sensor, and thermometer are installed in envi-cone penetrometer system. This envi-cone penetrometer system provides a continuous profile of measurements, and it is rapid, repeatable, reliable and cost effective for investigation of contaminated ground surrounding the underground oil storage tanks.

• 센서학회지
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• 제21권4호
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• pp.311-317
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• 2012

Disposable amperometric screen-printed biosensor strips have been fabricated by a sol-gel encapsulation for the analysis of glucose. The glucose oxidase(GOx) is entrapped in the gel matrix through sol-gel transition of tetraethoxysliane(TEOS). The biosensor is fabricated by GOx containing thin film of TEOS gel on the surface of screen-printed carbon electrode(SPCE). The GOx-containing thin film of TEOS gel offers a one-step modification process on the surface of SPCE. The optimum conditions for glucose determination have been characterized with respect to the applied potential, enzyme loading ratio, and pH. The linear range and detection limit of glucose detection were from 2.0 mM to 16.0 mM and 0.25 mM, respectively.

• 센서학회지
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• 제19권5호
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• pp.356-360
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• 2010

Due to the high surface-to-volume ratio, the 3-dimensional(3D) nanostructures of metal oxides are regarded as the best candidate materials for the chemical gas sensors. Here we have synthesised flower-like 3D zinc oxide nanostructures through a simple hydrothermal route. Specific surface area of the 3D zinc oxide nanostructures synthesised in different pH values from 9.0 to 12.0 were evaluated by using a BET analyzer and the results were compared with that of a zinc oxide thin film fabricated by rf sputtering. Using interdigitated electrodes, superior CO gas sensing properties of the 3D zinc oxide nanostructures on the ZnO thin film to those of the ZnO thin film were demonstrated.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전기물성,응용부문
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• pp.37-39
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• 2002

UHF method is very effective to diagnosis for partial discharge of GIS. In generally, inner UHF sensor can be attached on sheath cover of GIS under construction for periodic inspection. However, there is no inner UHF sensor for GIS of the domestic substation. We used the outer UHF sensor attached on spacer for GIS of existing substation. In this paper, we report the diagnosis result of partial discharge on 800kV GIS in domestic substation. From these results, we can find the quantity, reason and location of PD and certificate the performance of UHF method for partial discharge diagnosis of GIS.

• 소성∙가공
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• 제31권2호
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• pp.103-108
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• 2022

Systematic quality control based on real time data is required for modern factories. This study introduced a method of predicting punch wear in the trimming process of automobile parts. Based on monitoring data of the mass production process using a bolt-type piezo sensor, it was shown that precursor symptoms of die wear could be predicted from the change in load pattern with respect to production volume. The load pattern that changed according to the wear of the die was verified by numerical analysis.

• 센서학회지
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• 제32권6호
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• pp.487-495
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• 2023

Over the past few decades, considerable research has been conducted on field-effect transistor (FET) biosensors; however, other than electrochemical sensors for pH, they have not reached the commercialization stage and still remain at the basic research level. Although several reports have been published on experiments with real biological samples, no reports exist of developments that have reached commercialization or finalized approval for use. In this paper, we explain the reason for the experiments of FET biosensors to induce spurious signals in an experimental setup and explain the existence of misunderstandings regarding the operating principle of FET biosensors owing to the spurious signals. Based on the thoughtful review of the results of previously published papers, we show that the electrochemical read-out principle of FET biosensors requires our intensive understanding of the interfacial potential between the solution and the sensor electrode for further progress in the FET biosensor research.

• 한국전자통신학회논문지
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• 제12권3호
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• pp.477-484
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• 2017

기존의 순환여과식 양식장에서는 전문 인력의 부족, 수입 측정 장비에 대한 높은 의존도 등으로 인하여 많은 어려움을 격고 있다. 이에 본 논문에서는 최신 IoT기술을 적용한 광학식 센서(pH, DO)를 이용하여 양식장 수조 내 오염도를 빠른 시간내에 측정할 수 있는 자동 수질 측정 시스템을 구현하고자 한다. 기존 시스템의 문제점은 양식장 수조를 사람이 일일이 확인하거나, 측정 장비를 수조 속에 넣고 직접 측정을 하여 물고기의 생육에 좋지 않은 영향을 주는 것이다. 본 논문에서는 시스템은 측정 장비를 수조 속에 담그지 않고 간접 측정을 하는 방식을 제안하고 염분 및 다수의 오염 물질이 포함된 환경에서도 양식장 내의 물고기의 생육에 영향을 주지 않고 지속적인 측정이 가능한 시스템을 개발하였다.