• Journal of the KSME
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• v.31 no.6
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• pp.512-518
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• 1991

TSI IFA 100 Thermal anemometer와 같이 자동화된 유속계라 할지라도, 사용자가 조정해야 하는 과열비, 인덕턴스 등과 같은 인자가 있다. 이와 같은 조정의 문제 외에도 오차를 고려해야 하는 많은 요소가 있다. 이들 중 주위 유체의 온도 변화에 대한 영향 등에 깊은 이해를 가지고 있어야 정밀계측을 가능하게 할 것이다. 그 예로서 자동차에서 사용되는 정온도형 열선유속계 형의 공기유량계는 주위온도 보상을 위한 회로가 내장되어 동절기와 하절기 사이의 온도차를 보상하고 있다.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2010.04a
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• pp.791-794
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• 2010

고속도로에서 주행속도가 높아지게 되면, 도로의 노면 상태에 따라 차량의 안전과 쾌적한 운전자의 환경이 변화될 수 있다. 이처럼 도로의 노면 상태를 결정하는 주된 인자는 도로의 평탄성과 소성변형에 의한 노면의 요철이라고 할 수 있다. 평탄하지 못한 도로를 자동차가 고속으로 주행하게 되면, 자동차의 속도에 의한 도로와의 마찰이 발생하여 자동차에는 매우 큰 흔들림이 발생하게 된다. 또한, 도로의 경우에도 자동차의 차축과 도로면에서 발생하는 충격에 의해 미세한 진동이 발생하게 된다. 그리고 광섬유 브래그 격자(FBG)센서는 외부에서 작용하는 매우 미세한 물리량에 의한 변화의 측정이 가능한 매우 우수한 계측 센서로 사용이 가능하기 때문에 온도보상형 광섬유진동센서를 제작하였고, 이를 고속도로 포장면의 평탄성 모니터링에 활용하고자 하였다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.4C
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• pp.163-174
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• 2009

Mechanical device using the load cell or strain gage sensor can be influenced by tempearute changes because temperature change can cause a shift in the load cell or straing gage output at zero loading. In this paper, micro cone penetrometers with 1~7mm in diameter, are developed by using an optical fiber sensor (FBG: Fiber Bragg Grating) to compensate the continous temperature change during cone penetration test. Note the temperature compensated method using optical fiber sensor which has hair-size in diameter, and is not affected by environmental conditions because the measured data is the wavelength shifting of the light instead of the intensity of the electric voltage. Temperature effect test shows that the output voltage of strain gage changes and increases with an increase in the temperature. A developed FBG cone penetrometer, however, achieves excellent temperature compensation during penetration, and produces continuous change of underground temperature. In addition, the temperature compensated FBG cone shows the excellent sensitivity and detects the interface of the layered soils with higher resolution. This study demonstrates that the fiber optic sensor renders the possibility of the ultra small size cone and the new fiber optic cone may produce more reliable temperature compensated tip resistance.

• Journal of Sensor Science and Technology
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• v.7 no.3
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• pp.171-178
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• 1998

Silicon piezoresistive absolute pressure sensor for gas leakage alarm system was developed. This sensor must operate normally in the range of $0{\sim}600\;mmH_{2}O$ pressure, and $0{\sim}100^{\circ}C$ temperature. To make the most of this sensor for gas leakage alarm system, gas must not leak from the sensor itself when the diaphragm of the sensor fractures. Thus, the sealed diaphragm cavity was anodically bonded to pyrex 7740 glass under the condition of $10^{-4}$ torr, at $400^{\circ}C$. The sensitivity of developed sensor was $4.06{\mu}V/VmmH_{2}O$ for $600\;mmH_{2}O$ full-scale pressure range. And temperature compensation method of this sensor is to change bridge-in put-voltage linearly in proportion to the temperature variation by using diode(PXIN4001) or Al thin film resistor. By these methods the temperature effect in the range of $0{\sim}100^{\circ}C$ was compensated over 80 % for offset drift, 95 % for sensitivity.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.43 no.6 s.312
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• pp.33-39
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• 2006

Trichromatic LED backlight renders higher colour gamut and panel transmittance to the LCDs than the phosphor-converted white LED backlight. In realization, however, several technical challenges arise, such as colour shift, due to the ambient temperature change, brightness decrease along with the temperature increase, colour mixing, minimizing the total number of chips and so on. In this paper we designed and tested the low cost temperature compensating circuit, using a thermistor as a temperature compensating element, for stabilizing the brightness and maintaining the colour coordinates of the trichromatic backlight units. By applying the temperature compensating circuit, the decrement rate of the brightness and colour shift rate were achieved by 54% and 51% respectively comparing with uncompensated case.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2022.06a
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• pp.50-51
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• 2022

현재 사용되는 2차 전지의 특성상 저온 및 고온에 반응하는 특성이 나타나고 있다. 이러한 특성을 고려하여 충방전제어를 진행하면서 사용 되는 2차 전지의 활용을 최대한 운영이 가능한 방법을 제시 하고자 한다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.4C
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• pp.117-125
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• 2011

The practical use of the electrical resistivity, which can makes the acquirement of the high resolution data in specific area, is increased in order to obtain a reasonable data for a ground investigation. The objective of this study is development of TRPF(Temperature-compensated Resistivity Probe for Field test), and an application in the field test for obtaining a reliable electrical resistivity value about considering the temperature effects. Temperature sensor is attached at 15mm, 30mm, 90mm below from the cone tip in consideration with the results of temperature transient process of cone probe and safety, and the angle of cone tip is $60^{\circ}$ for geometrical reason and minimizing the disturbance during the penetration test. Diameter of the cone probe is equally 35.7mm and penetration rate is 2 cm/sec for a comparison with standard cones such as CPT and SPT, and others. The temperature change is instantly observed around $4^{\circ}C$ when touching the ground, and the comparing results among the other cones indicates that the temperature compensation should be conducted in the ground survey using the electrical resistivity. This study shows that the necessity of temperature effects compensation during penetration test through the development and field verification of TRPF (Temperature-compensated Resistivity Probe for Field test).

• Journal of the Korean GEO-environmental Society
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• v.12 no.1
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• pp.51-60
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• 2011

Electrical resistivity is applied for understanding details about layers and obtaining basic properties of soils to various measurement devices. The objective of this study is development of TRP(Temperature-compensated Resistivity Probe), analysis about effects of temperature changes during cone penetration test, and observation of characteristics of cone penetration. In order to observation of temperature changes according to a diameter difference of resistivity cone probe, the cone which has wedge type cone tip is made to two types, 2mm and 5mm. Temperature sensor is attached at 15mm below from cone tip because of an electrical interference with elecrical resistance probe. Delectrical connector is used to prevent electric disturbance between motor type penetrating machine and electrical resistivity cone probe. Application tests are carried out in acrylic cell whose diameter is 30cm with uniform Jumunjin sand according to densification caused by blows. The test results indicate that the temperature is increased uniformly during penetration and a tendency, characteristics of cone penetration, is discovered during altering state of soils. This study suggests that the temperature effects and characteristics of penetration should be considered in penetrating tests in order to conduct an accurate ground investigation using TRP(Temperature-compensated Resistivity Probe).

• Journal of the KSME
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• v.33 no.9
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• pp.793-802
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• 1993

이 글에서는 부 온도저항계수를 갖는 탄소파이버를 열선으로 이용하고 이를 구동한는 증폭회로의 구성에 관한 연구, 3차원 속도측정용 열선프로브의 접지단자를 3개의 열선이 공통으로 사용하는 공통접지 삼축 열선프로브와 유속계의 특성에 대해 고찰한다. 또한 과열비가 다른 두 개의 저 온도형 열선 유속계를 이용하여 유동장의 온도와 속도를 동시에 측정한는 방법과 임의 형태의 유체온도정보를 이용한 열선유속계의 일반적인 온도보상방법에 관하여 논의하여 열선유속계의 원리와 그 응용 등을 간단히 설명함으로써 관심 있는 분들의 이해를 돕고자 한다.

• Journal of the Korean Institute of Gas
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• v.11 no.1 s.34
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• pp.40-45
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• 2007

This paper describes NDIR $CO_{2}$ gas sensor that shows the characteristics of temperature compensation. It consists of novel optical cavity that has two elliptical mirrors and a thermopile that includes ASIC chip in the same metal package for the amplification of detector output voltage and temperature sensor. The newly developed sensor module shows high accuracy ($less\;than {\pm}40\;ppm$) throughout the measuring concentration of $CO_{2}$ gas from 0 ppm to 2,000 ppm. After implementing the calculation methods of gas concentration, which is based upon the experimental results, the sensor module shows high accuracy less than ${\pm}5\;ppm$ error throughout the measuring temperature range ($15^{\circ}C\;to\;35$^{\circ}C$) and gas concentrations with self-temperature compensation.