• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 C
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• pp.1668-1670
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• 2003

This paper deals with a development of the high precise measuring device of resistive leakage current for the deterioration and diagnosis of ZnO arresters. The resistive leakage current increasing with time leads to a thermally unstable state that may even experience a disaster. So, the resistive leakage current can be used as an indicator to discriminate whether the ZnO arrester blocks is in good state or in bad. The resistive leakage current measuring system with an analysis program operated with micro-processor using the time delay addition method was designed and fabricated. The proposed measuring systems for the resistive leakage current can effectively be used to develop the techniques of forecasting the deterioration of ZnO arresters in electric power systems.⨀ᔌ?؀㔳㤮㈻Ԁ䭃䑎䷗ᜒं6〰Ԁ䭃䑎䴀

• 한국정밀공학회지
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• 제17권8호
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• pp.60-70
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• 2000

In this paper a 3D position measuring device that finds the 3D position of an arbitarily placed object using a camersa system is introduced. The camera system consists of three stepping motors and a CCD camera and a laser. The viewing direction of the camera is controlled by two stepping motors (pan and tilt motors) and the direction of a laser is also controlled by a stepping motors(laser motor). If an object in a remote place is selected from a live video image the x,y,z coordinates of the object with respect to the reference coordinate system can be obtained by calculating the distance from the camera to the object using a structured light scheme and by obtaining the orientation of the camera that is controlled by two stepping motors. The angles o f stepping motors are controlled by a SGI O2 workstation through a parallel port. The mathematical model of the camera and the distance measuring system are calibrated to calculate an accurate position of the object. This 3D position measuring device can be used to acquire information that is necessary to monitor a remote place.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 신호처리소사이어티 추계학술대회 논문집
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• pp.549-552
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• 2003

The electrical current generated by heart creates not only electric potential but also a magnetic field. We have observed electrophysiological phenomena of the heart by measuring tangential components of magnetocardiogram(MCG) using 61 channel superconducting quantum interference device(SQUD) system. In this paper, we developed a new analysis method, which is based on the theory of electromagnetic field. We show some differences of the current direction between the normal MCG and the abnormal(ischemic heart disease) MCG.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.2357-2364
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• 2011

Diesel locomotive operates the generator with the power from the diesel engine, and it consists of the typical serial-hybrid system which operates the train wheels by converting its generated electric energy into the torque of DC (or AC) motor. However, the technology of locomotives is only focused on trains' controlling power generation mechanism. Hence, it is a current issue that the efficiency of its engine and its generator is relatively lower than that of auto vehicles'. Particularly, since there are no proper equipment to measure the amount of fuel which is essentially necessary for the efficient use of fuel, it is not easy to confirm the instant amount of fuel use as well as the exact average fuel consumption per an hour. Due to those difficulties, it is urgent to develop the device that measures the fuel consumption. Plus, this use of the developed measuring device allows the various and useful analysis relating to the fuel consumption, and this could lead to establishing the efficient driving pattern regarding to fuel saving. This device consists of two flux (fuel level) measuring censors, MCU for calculating the measured values, the information recorder for saving measured values, and the display device for indicating the fuel amount consumed during driving.

• 한국안전학회지
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• 제30권6호
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• pp.117-121
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• 2015

$O_2$-deficiency related accidents occur every year and the most effective way to prevent them is to measure $O_2$ concentration in air with a properly-calibrated $O_2$ monitoring device before entering low-$O_2$ areas. An electro-chemical sensor, Texas Instrument gas platform, and iPhone are used to construct a smartphone-based $O_2$ monitoring device. The smartphone based $O_2$ measuring approach offers advantages of small size, accessibility, internet-connectivity, and programmability in comparison to conventional $O_2$ measuring devices. Multiple gas sensors can be conveniently interfaced to single smartphone, allowing for creating a network of gas sensors distributed across workplaces and remote monitoring via existing mobile communication network. To check proper function of the $O_2$ monitoring device the sensor was exposed to shallow and deep human breaths. The readings decreased immediately after being exposed to exhalation and recovered during inhalation to a calibrated level of 20.9%. When readings decreased below a preset warning value of 19.5%, a low $O_2$ warning was successfully activated on the smartphone.

• 센서학회지
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• 제27권6호
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• pp.386-391
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• 2018

To analyze the film cooling in a liquid rocket engine, it is necessary to understand the characteristics of the wall-impingement liquid film. We designed an optimal two-dimensional device for measuring the thickness of the liquid film thickness. This device quantitatively measures the liquid-film thickness distribution. In previous liquid-film thickness measuring devices, the liquid film was formed over the entire area of the sensor. However, its formation depended on injection conditions. To compensate for this, optimal resistors are selected. Additionally, saturation variations with partial saturation are analyzed. Furthermore, calibration using the enhanced plate method is conducted with improvements in spatial resolution. The device designed here can be used to analyze the properties of an impingement liquid film with a slit injector. This study can be used for film-cooling analysis in liquid rocket engines.

• 콘크리트학회논문집
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• 제24권5호
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• pp.535-542
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• 2012

매스 콘크리트에서 발생하는 수화열을 예측하기 위한 단열온도상승시험은 시험 비용이 고가이고 시공간상 제약으로 인해 한계가 있는 실정이다. 이에 신속하고 경제적이며 간편한 간이 수화열 측정 장치의 개발이 필요한 실정이다. 이 연구에서는 간이 수화열 측정 장치를 완성하기 전 단열 성능이 뛰어난 보온병에 콘크리트를 타설하고 열손실량을 보정하여, 간이 수화열 측정 장치의 타당성을 입증하고자 하였다. 열손실량을 정확히 예측하기 위해서는 측정 장치의 정확한 열손실계수를 추정하는 것이 필수적인데, 열손실계수는 단열 장치 내부의 수온 변화를 이용하여 추정하였다. 시험 결과 장치 고유의 열손실계수는 외부 온도와 습도, 내부 온도 변화에 크게 변하지 않는 것으로 드러났다. 실제 단열온도상승시험과 열손실량이 보정된 보온병의 단열온도상승량과의 검증 시험을 통해 이 연구의 객관성과 타당성을 입증할 수 있었다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2015년도 제51회 KOSCO SYMPOSIUM 초록집
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• pp.307-308
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• 2015

• 한국임상수의학회지
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• 제13권2호
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• pp.140-143
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• 1996

In this paper the development of an automatic body temperature measuring system which can be attached to the milking machine has been studied. Since the disease is highly related to the body temperature of the cattle, early detection of the abnormal temperature would prevent the severe problems which may occur in dairy farms. The electronic component AD590 is used as a temperature sensor for the system. The device is highly robust against the noise since the output signal is the current. So it can be applied to the long distance sensing. The resolution of the signal is $0.1{\circ}C$ and the current is 10 mV. Also the A/D converter is designed for interfacing the sensor with a computer. A temperature measuring experiment using the developed system has been done for measuring the temperature of human beings and the system was proven to be useful for measuring the body temperature of the dairy cattle properly.

• 반도체디스플레이기술학회지
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• 제18권1호
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• pp.15-20
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• 2019

Inspection and measurement of surface quality is one of the most critical processes for manufacturing products such as semiconductor wafers, sapphire substrates, and display panels. The vibrations of the inspection and measurement devices are supposed to be the most dominant factors for severe measurement errors and longer measuring time. In this study, dynamic characteristics of an inspection and measurement device are analyzed through frequency response experiment and computer simulation to obtain parameters such as frequencies, magnitudes, mode shapes, and periods of vibrations. And then an active damper which consists of sensor, interface board, and actuator is designed based on the parameters to formulate the most effective reaction signal to suppress the vibrations which is generated by an interface board, and provided by an actuator. If the vibrations are measured by the sensor, the active damper immediately generates and provides the corresponding reaction signal to inspection and measurement device. The result shows that the active damper can suppress structural vibrations effectively and reduce measuring time of the device and enhance the productivity.