• 한국통신학회논문지
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• 제17권12호
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• pp.1423-1436
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• 1992

이 논문에서는 멀티태스킹을 지원하는 CAT인터페이스를 구현하였다. 컴퓨터와 계측기를 연결하기 위해 인터페이스 카드를 제작하고 구현하였다. OOP와 CUI를 사용한 컨트롤과 디스플레이는 C++로 프로그램되었다. 스펙트럼 분석기와 전력계가 제어할 계측기로 선택되었다. 9개의 모듈이 여러가지 자원을 공유하도록 구성되었다. 또한, 여러대의 계측기를 동시에 측정하기 위해 멀티태스킹이 구현되었다. 멀티태스킹은 시간분할 DOS환경에서 수행되었다. 멀티태스킹은 프로세싱 기법으로 트레드 방식을 사용하였고 스케줄링으로 라운드 로빈방식을 사용하였다. 다른 목적계측기를 위해서는 목적 계측을 구동할 소프트웨어만 합하면, 시스템은 더 많은 계측기를 컴퓨터에 의해 동시 측정할 수 있다. 사용자는 전문가적인 지식없이 시간과 오차를 줄일 수 있다.

• 한국정밀공학회지
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• 제18권10호
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• pp.84-92
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• 2001

Commercial eddy current dynamometers control the torque of rotating body, power supply machine, with the field coil current being operated as a braking force. In this paper, we studied the relation between field coil current and torque load of eddy current dynamometer. By the torque measuring analysis of eddy current dynamometer it is linear relation between the brake force measured from a torque meter which is installed at the case of dynamometer and the multiplied shaft rpm by the squares of field coil current (N$\times$I$^2$). To prove the relation, it was experimented and showed that the torque operated by the rotating body can be measured with the shaft rpm and the field coil current of the eddy current dynamometer. This result shows a possibility that eddy current dynamometer can measure the torque of rotating body without a torque measuring device. such as load cell.

• 센서학회지
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• 제14권4호
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• pp.244-249
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• 2005

In this study, radiation sensor tips are fabricated for remote sensing of X or gamma ray with inorganic scintillators and plastic optical fiber. The visible range of light from the inorganic scintillator that is generated by radiation source is guided by the plastic optical fiber and is measured by optical detector and power-meter. Two kinds of sensor tips are designed and fabricated such as film type and powder type. Many kinds of inorganic scintillators are used to fabricate both sensor tips, and the different wavelength of emitting lights from them are measured to determine the optimal inorganic scintillator which has maximum light output. As a radiation source X-ray generator and Ir-192 are selected to test a performance of sensor tip. It is expected that the fiber-optic radiation sensor is widely used in nuclear industry and medical applications due to its special characteristics such as good flexibility, easy in processing, long lengths and no interference to electro magnetic field.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권8호
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• pp.3103-3120
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• 2015

This paper presents a single-phase energy metering chip with built-in calibration function to measure electric power quantities. The entire chip consists of an analog front end, a filter block, a computation engine, a calibration engine, and an external interface block. The key design issues are how to reduce the implementation costs of the computation engine from repeatedly used arithmetic operations and how to simplify calibration procedure and reduce calibration time. The proposed energy metering chip simplifies the computation engine using time-division multiplexed arithmetic units. It also provides a simple and fast calibration scheme by using integrated digital calibration functionality. The chip is fabricated with 0.18-μm six-layer metal CMOS process and housed in a 32-pin quad-flat no-leads (QFN) package. It operates at a clock speed of 4096 kHz and consumes 9.84 mW in 3.3 V supply.

• 한국자동차공학회논문집
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• 제5권6호
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• pp.175-182
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• 1997

The purpose of this study is to investigate the effects of intake manifold shapes to improve the engine performance in a 3-cylinder LPG engine with a closed loop fuel supply system. To know the flow resistance of intake manifolds with shape, the intake negative pressure of each runner in intake manifolds were measured by using the digital pressure meter at each driving condition. And, the engine torque and power have been measured with an engine dynamometer while adjusting the optimal fuel consumption ratio with a solenoid driver. As 속 results form this experiment, the torque characteris- tics were more improved with the plenum chamber(B type intake manifold) than with the banana type(A type intake manifold). The torque characteristics were improved at mid-engine speed(rpm) range as the inner diameter of the intake manifold became smaller. And also the optimum volume among the examined plenum chamber volume was 0.74 times(590cc) the displacement of the test engine.

• 한국자동차공학회논문집
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• 제19권5호
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• pp.51-57
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• 2011

Parametric studies based on analysis of lubrication system of a four cylinder gasoline engine are illustrated system in this paper. In development process of engine lubrication system, parts of failure cases are related with oil pull over and oil churning phenomenon. The crankcase & head system pressure by oil churning phenomenon are gradual increased. It cause oil pull over phenomenon at engine breather line and oil over-consumption. In order to improve oil reduction and oil pull over phenomenon are also considered in the developing state. For this study, the characteristics of engine lubrication system are measured at various tilting angle and drain hole sizes. In addition, the oil flow & oil quantity are tested by blow by meter and catch jar. Results are presented to stabilize the oil supply system at sever driving condition. The data from present study are available for the engine lubrication system.

• 수산해양기술연구
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• 제34권2호
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• pp.200-211
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• 1998

Heat transfer performance improvement by fin and groovs is studied for condensation of R-11 on integral-fin tubes. Eight tubes with trapczodially shaped integral-fins having fin density from 748 to 1654fpm(fin per meter) and 10, 30 grooves are tested. A plain tube having the same diameter as the finned tubes is also used for comparison. R-11 condensates at saturation state of 32 $^{\circ}C$ on the outside tube surface coded by inside water flow. All of test data are taken at steady state. The heat transfer loop is used for testing singe long tubes and cooling is pumped from a storage tank through filters and folwmeters to the horizontal test section where it is heated by steam condensing on the outside of the tubes. The pressure drop across the test section is measured by menas pressure gauge and manometer. The results obtained in this study is as follows : 1. Based on inside diameter and nominal inside area, overall heat transfer coefficients of finned tube are enhanced up to 1.6 ~ 3.7 times that of a plain tube at a constant Reynolds number. 2. Friction factors are up to 1.6 ~ 2.1 times those of plain tubes. 3. The constant pumping power ratio for the low integral-fin tubes increase directly with the effective area to the nominal area ratio, and with the effective area diameter ratio. 4. A tube having a fin density of 1299fpm and 30 grooves has the best heat transfer performance.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전력기술부문
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• pp.146-148
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• 2001

This paper discusses the optimal sizes of BESS. The goal must be optimized electricity charge of the customers-side with choosing the time-of-use rates. Therefore the cost is minimized by BESS installed the customers-side. Feasible ROR that means the ratio of capital costs to economic effect owned the optimal BESS sizes is determined the suitable domestic condition based on the battery cost and power converter system cost. Payback period times can be presented by BESS through the ROR. Multi-Pass Dynamic Programming(MPDP) algorithm is applied to the customer for the optimal sizes determination in this paper. It is to solve the optimal solution under the constraints. To investigate the efficiencies of the constraints, it is applied the typical load curve to the high-voltage customer owned Time-Of-Use(TOU) whether BESS is installed or not. Well, The result is obtained that feasible BESS sizes can be achieved the suitable customers-side of meter through the ROR.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2016년도 추계학술대회 논문집
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• pp.116.1-116.1
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• 2016

반도체 가스센서에서는 가연성 및 탄화수소계 가스를 감지 하기 위해서 $100{\sim}500^{\circ}C$ 이상의 동작온도를 필요로 한며, 이에 따라 반도체식 가스센서의 마이크로 히터 소재는 고온에서 열적 안정성이 있는 소재가 요구된다. 현재 상용화되고 있는 반도체식 가스센서는 실리콘(Silicon) 기반의 MEMS 기술을 이용한 가스센서이며, 구조적으로나 성능적 한계가 드러남에 따라 실리콘 이외의 다양한 재료의 MEMS 응용기술 개발이 필요한 실정이다. 본 연구에서는 이러한 실리콘의 재료적 한계를 극복하기 위해 다공성 알루미늄 산화물(AAO)을 기판으로 사용하여 마이크로 히터를 제작하였다. AAO의 제작에 앞서 CMP, 화학연마, 전해연마를 이용하여 적합한 전처리 공정을 선정하였고, AAO 제작 시 온도, 시간, 전압의 변수를 주어 마이크로 히터 기판에 적합한 공정을 탐색하였다. 마이크로 플랫폼은 MEMS 공정으로 제작되었으며, PR(Photo Resist)을 LPR(Liquid Photo Resist)과 DFR(Dry Film Resist)로 각각 2종 씩 선택하여 AAO에 적합한 제품을 선정하였다. 제작된 마이크로 히터는 $1.8mm{\times}1,8mm$로 소형화 하였고, 열손실의 제어를 위해 열확산 방지층을 추가하였다. 구동 온도, 소비전력, 장시간 구동시 안정성의 측정 및 평가는 적외선 열화상 카메라와 kiethly 2420 source meter를 이용하여 측정하였으며, 열확산 방지층의 유 무에 따른 온도 분포 및 소비전력을 비교평가 하였다. 최종적으로는 현재 사용화 되어있는 가스센서들의 소비전력과 비교 평가 하여 논의 하였다.

• 드라이브 ㆍ 컨트롤
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• 제14권1호
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• pp.35-40
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• 2017

Whereas fuel economy of a vehicle is measured using a chassis dynamometer, that of construction machinery such as an excavator shall be presumably measured using simulated work cycle. In order to measure fuel consumption under a simulated work cycle, a measurement methodology, while excavator operates in dynamic(transient) motion, needs to be examined and developed. In this work, three methods (gravimetry, ECU CAN signal and mass flow meter) are studied and compared. This work reveals that when ECU CAN signal is properly calibrated and evaluated, compared to gravimetry or mass flowmeter, it could be used to measure fuel consumption with accuracy and thus for approval of the fuel economy of construction machinery.