• 센서학회지
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• 제15권3호
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• pp.164-167
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• 2006

Calorimeter is one of widely used biosensors. Conventional or existing calorimeters are realized directly on a silicon wafer which has very high thermal conductivity. It results in decreasing temperature difference between junctions and it makes a sensitivity of calorimeter to be decreased. In this study, the microcalorimeter was made by using MEMS(Micro Electro Mechanical Systems)-technology and hot junctions of the microcalorimeter are released from a silicon substrate to reduce loss of generated heat by reactions between biomolecules. Sensitivity of the released microcalorimeter was 18 mV/M which is 1.5 times higher than another calorimeters on silicon substrate by reactions between biotin and streptavidin.

• Transactions on Electrical and Electronic Materials
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• 제3권2호
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• pp.28-31
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• 2002

The Cdl-xZnxTe film was fabricated by thermal evaporation for the flat-panel X-ray detector. The stoichimetric ratio and the crystal structure of a polycrystalline Cd$_{1-x}$ Zn$_{x}$Te were investigated by EPMA and XRD, respectively. The leakage current and X-ray sensitivity of the fabricated films were measured to analyze the X-ray response characteristic of Zn in the polycrystalline CdZnTe thin film. The leakage current and the output charge density of Cd$_{0.7}$Zn$_{0.3}$Te thin film were measured to 0.37 nA/cm$^2$ and 260 pc/cm$^2$ at an applied voltage of 2.5 V/${\mu}{\textrm}{m}$, respectively. Experimental results showed that the increase of Zn doping rates in Cd$_{1-x}$ Zn$_{x}$Te detectors reduced the leakage current and improved the signal to noise ratio significantly.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 정기총회 및 추계학술대회 논문집 학회본부
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• pp.188-191
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• 1993

Silicon flow sensor which can detect the magnitude and direction of two dimensional air flow was designed and fabricated by CMOS process and bulk micromachining technique. The flow sensor consists of three-layered dielectric diaphragm a heater at the center of the diaphragm and four thermopiles surrounding the heater at each side of diaphragm as sensing elements. This diaphragm structure contributes to improve the sensitivity due to excellent thermal isolation property of dielectric materials and its tiny thickness. The flow sensor has good axial symmetry to sense 2-D air flow with the optimized sensing position in the given structure. Measured sensitivity of our sensor is $18.7mV/(m/s)^{1/2}$.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(2)
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• pp.73-76
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• 2002

In this paper we present an integrated Hail sensor It for fan motors, fabricated in industrial bipolar process. As a discrete Hall sensor and signal processing circuitry In the fan motor system were Integrated into single chip a temperature dependence of Hall sensitivity and Hall offset voltage can be compensated and cancelled by on-chip circuitry. We Propose a novel temperature compensation of Hall sensitivity with negative temperature coefficient (TC) using the differential amplifier gain with Positive TC. After a package of the chip was sealed using a plastic Package 20 Pins, the thermal and magnetic characteristics were investigated. The obtained experimental results are in agreement with analytical predictions and have more excellent performance than\ulcorner conventional the fan motor system using discrete Hall sensor.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 추계학술대회 논문집
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• pp.247-248
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• 2006

• 전자공학회논문지D
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• 제34D권7호
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• pp.30-36
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• 1997

Bump bonded piezoesistive silicon accelerometer was fabricated by the porous silicon micromachining and th eprocess technique of integrated circuit. The output voltage of the accelerometer fabricated on (111)-oreiented Si substrates with n/n$^{+}$n triple layers showed good linear characteristic of less than 1%. The measured sensitivity and the resonant frequency was about 743 .mu.V/g and 2.04 kHz, respectively. And the transverse sensitivity of 5.2% was measured from the accelerometer. Also, to investigate an influence on the output characteristics of the sensor due to bump bonding, the values of the piezoresistors were measured through thermal-cycling test in the temperature variation form -50 to 120.deg. C. Then, there was 0.014% resistance changes about 3.61 k.ohm., so sthe output charcteristics of the sensor was less affected by bump bonding.g.

• 신재생에너지
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• 제10권2호
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• pp.40-47
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• 2014

This study is intended to analyze the appropriate scope for 9.9MW biomass cogeneration, feasibility and sensitivity according to changing market situation. In the study, the heat load is classified into three types to predict heat sales and find out the appropriate scope of thermal business that is operated in CHP 34.42 Gcal/h, PLBwg 70 Gcal/h of cogeneration. the feasibility is estimated based on internal rate of return (IRR) and net present value(NPV). the sensitivity is analyzed in terms of biomass fuel cost, unit price of heating cost, investment cost, SMP unit price and REC unit price.

• 설비공학논문집
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• 제12권6호
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• pp.599-608
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• 2000

One dimensional numerical modeling was carried out for the melting behavior of dry snow and the unsaturated flow when heat was supplied from the bottom surface. Discrepancy between the previous experimental data and the present numerical results is substantially reduced by considering the density change of water permeation layer due to the infiltration of meltwater. In the parametric study for effective thermal conductivity, it was found that the effect of this parameter to the behavior of snow melting is minor. Sensitivity analysis showed that the melting time is most sensitive to changes in supplied heat flux, snow temperature, and bulk density, whereas snow bulk density and residual saturation have a significant effect on the height of water permeation layer in snow.

• 열처리공학회지
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• 제36권4호
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• pp.237-241
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• 2023

Recently, research on flexible sensors for personal health management has been gaining attention. In this study, we fabricated a crack-based flexible sensor in thin film form to measure the pulse on the wrist. We evaluated the characteristics of the sensor based on the curing conditions of the PDMS (Polydimethylsiloxane) film to optimize the sensor's gauge factor. The modulus of PDMS varies depending on the curing conditions. In this case, the modulus of PDMS has a significant influence on crack formation, leading to changes in the sensitivity of the sensor. This study examined the changes in the gauge factor associated with these variations.

• 콘크리트학회논문집
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• 제24권6호
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• pp.651-658
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• 2012

이번 연구에서는 비선형 음향효과를 기반으로 한 비선형 초음파 변조 기법을 통해 열손상 콘크리트의 미세균열 정도를 평가할 수 있는 방법을 제안하였다. 화재 시 콘크리트 구조물은 물리적, 화학적 변화에 따른 콘크리트 내 미세균열이 발생하므로, 기존 초음파 비파괴 기법의 민감도 한계를 극복한 비파괴 기법의 도입이 필요하다. 비선형 초음파 기법은 초음파와 저주파의 변조파로부터 열손상 평가 인자인 비선형인자를 측정하며, 이는 열손상 콘크리트의 미세균열에 적합한 민감도를 가진다. 이 연구에서는 SEM 관측, 열손상 전후 콘크리트의 투수공극량 변화 측정으로부터 수열온도에 따라 미세균열이 급격하게 발생함을 보였으며, 수열온도별 콘크리트의 초음파 전파속도 측정을 통해 제안된 방법의 민감도를 검증하였다. 추가적으로 열손상에 따른 미세균열이 콘크리트의 성능저하에 미치는 영향을 파악하고자 열손상 콘크리트 시편의 압축강도 측정을 수행하였다. 측정값 및 실험값의 연관성을 파악하여 비선형 초음파 변조 기법이 열손상 콘크리트의 미세균열 평가에 적합함을 보였으며, 향후 압축강도 추정에 대한 적용 가능성을 확인하였다.