• Proceedings of the KIEE Conference
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• 1995.11a
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• pp.376-378
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• 1995

A method is presented for the design and fabrication of the temperature compensation circuits on the Clark electrodes for measuring the dissolved oxygen(DO) concentration. The discussion includes a method of the sensor interface circuits for the DO sensor. Typical polarograms for the DO probes under test using this sensor circuits are presented. High accuracy over 99 % of the I to V conversion using the proposed circuit is verified. Temperature dependence for the test DO probe is well compensated automatically using the thermistor($2k\Omega,\;25^{\circ}C$) in series with correction resistor in the feedback loop of the op-amp circuit in the temperature range of the 0-50$^{\circ}C$.

• Journal of Sensor Science and Technology
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• v.9 no.4
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• pp.268-273
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• 2000

This paper represents a hot-film flow sensor which is compensated by a noble temperature compensation method using the initial unbalanced voltage. The resistance value of the sensor is determined by using the graph of the initial unbalanced voltage of an open-loop circuit against the air temperature. The compensation is accomplished by applying the unbalanced ratio of the resistors in the Wheastone bridge circuit. In the range of air temperature of $-20^{\circ}C{\sim}120^{\circ}C$, the error is about ${\pm}1%$.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.06a
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• pp.528-531
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• 2007

This paper presents development of a 4-inch WVCA OCB (Optical Compensated Bend)-mode display panel. The developed panel has a built-in circuit of the LTPS (low temperature poly-Si)-integrated gate driver circuit with the function of black data insertion. The function of black data insertion makes it possible to realize rapid response time of 4ms and wide viewing angle of $160^{\circ}$. We also applied the RGBW pixel structure for the brighter image with relatively low power consumption. The developed panel showed improved optical efficiency and driving capability of stable image quality for OCB mode. We developed high efficiency OCB-mode panel with built-in integrated gate driver circuit using LTPS on panel without any external driver IC.

• 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.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.43 no.5 s.311
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• pp.28-35
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• 2006

This paper presents a new 3.3-1 V synchronous buck DC/DC converter that employs CMOS operational transconductance amplifiers (OTAs) as circuit-building blocks. An error amplifier OTA in a PWM circuit is compensated for to improve temperature stability. The temperature coefficient of the transconductance gain of the compensated OTA is less than $150\;ppm/^{\circ}C\;over\;0-100^{\circ}C$. The HSPICE simulation results of the $0.3{\mu}m$ standard CMOS technology show that the efficiency of the proposed converter is as high as 80% in the load current range of 40-125 mA. These results show that the proposed converter is adequate for use in battery-operated systems.

• Journal of Sensor Science and Technology
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• v.5 no.5
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• pp.63-68
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• 1996

In order to implement the integrated capacitive pressure sensors, which contains integrated interface circuits to detect the electrical output signal, several main factors that have a bad effect on the characteristics of sensors must be improved, such as parasitic capacitance effects, temperature/thermal drift, and the leakage current of a readout circuitry. This paper describes the novel design of the dedicated CMOS readout circuitry that is consists of two capacitance to frequency converters and 4 bit digital logic compensating circuits. Dividing the oscillation frequency of a sensing sensor by that of reference sensor, this circuit is designed to eliminate the thermal/temperature drift and the effect of the leakage currents, and to access a digital signals to obtain a high signal-to-noise(S/N)ratio. Therefore, the resolution of this circuit can be increased by increasing the number of the digital bits. Digital compensated circuits of this circuits, except for the C-F converters, are fabricated on a FPGA chip, and fundamental performance of the circuits are evaluated.

• Journal of Satellite, Information and Communications
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• v.3 no.1
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• pp.1-7
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• 2008

This Paper studied the design and measured results of a flight model for Ku-Band Linearized Channel Amplifier (LCAMP) for communication satellite onboard system. All MMICs, i.e. Variable Gain Amplifier (VGA), Variable Voltage Attenuator (VVA) with analog/digital attenuator, Branch line Hybrid Coupler and Detector for Pre-distorter are fabricated using Thin-Film Hybrid process. The performance of the fabricated module is verified through Radio Frequency circuit simulations and electrical function test in space environment for flight model at 12.25 to 12.75 GHz.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.158.3-158
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• 2001

In this paper, an instrumentation amplifier, which the voltage gain can be electronically adjusted, is proposed. The realization method is based on the use of operational transconductance amplifiers (OTAs) as active circuit elements. The common mode rejection ratio (CMRR) of the proposed scheme is better than 93dB at the frequency of about 70kHz. The temperature effect to the circuit performance is also compensated. Experimental and simulation results demonstrating the characteristics of the proposed scheme are also included.

• Journal of Sensor Science and Technology
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• v.4 no.2
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• pp.29-36
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• 1995

A constant solid state flow velocity/mass sensor has been fabricated and its characteristics were measured according to flow velocity and fluid temperature. Parameters of the sensor circuit were obtained by simulation using finite difference method. Sensitivity was 10mW/(cm/sec) in the range of flow velocity 0-45cm/sec and response time was within two seconds. For the experiment of fluid temperature variation, the sensor output was compensated at the rate of temperature variation $0.1^{\circ}C/min$, however, with the rate of $0.2^{\circ}C/min$ it took two minutes to be compensated. Since it is not quite often to have such a rate of temperature variation of $0.2^{\circ}C/min$ or more, the developed sensor output can be used for most applications to detect small amount of flow-rate.

• Journal of Veterinary Clinics
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• v.21 no.3
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• pp.270-275
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• 2004

Anesthetic machines may be equipped with either a precision or nonprecision vaporizer. A precision vaporizer is designed to deliver an exact concentration of anesthetic agent. Goldman vaporizer is a low-flow, closed-circle circuit with a low resistance vaporizer, in circuit. Vaporizers used within circle system(VIC) are not usually temperature compensated and this is generally thought to be a disadvantage. As the volatile agent is vaporized, heat is extracted from the liquid and temperature decreases. This cooling of the liquid leads to a decrease in concentration of the anaesthetic agent delivered by the vaporizer. The purpose of this study is to examine the mechanical consistency of the delivery of isoflurane from Goldman vaporizer and precision vaporizer at various gas flow rates and temperatures. And we first studied isoflurane concentration according to room temperature changes delivered by a Goldman vaporizer and precision vaporizer using different gas flow. The room temperature of $15^{\circ}C,$ $20^{\circ}C,$ $28^{\circ}C$ and fresh gas flow rates of 0.5, 1.0, 1.5, 2.0, 3.0 l/min were used. The inspired agent concentration was measured using a Datex-Ohmeda multigas analyzer. As rose in room temperature, the isoflurane concentration of precision vaporizer approximated the dial setting. On the other hand, at a dial setting concentration of 5.0 percent the delivered isoflurane concentration of precision vaporizer was more than the dial setting in high temperature. The isoflurane concentration of precision vaporizer remained constant despite the increase in temperature. The isoflurane concentration of Goldman vaporizer was increased with rise in room temperature and decreased with rise in gas flow.