• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2009년도 추계학술대회
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• pp.649-657
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• 2009

The paper presents the measurement split split-plot models for saving the time and cost. The split split-plot designs developed are efficiently used to estimating the gauge R&R(Reproducibility & Repeatability) when the completely randomized design of all factors(such as high pressure and temperature) is expensive and time consuming. The models studied include three split split-plots considering the type of experimental units.

• Korean Journal of Mathematics
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• 제21권2호
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• pp.125-150
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• 2013

The stabilized Gauge-Uzawa method (SGUM), which is a second order projection type algorithm to solve the time-dependent Navier-Stokes equations, has been newly constructed in 2013 Pyo's paper. The accuracy of SGUM has been proved only for time discrete scheme in the same paper, but it is crucial to study for fully discrete scheme, because the numerical errors depend on discretizations for both space and time, and because discrete spaces between velocity and pressure can not be chosen arbitrary. In this paper, we find out properties of the fully discrete SGUM and estimate its errors and stability to solve the evolution Navier-Stokes equations. The main difficulty in this estimation arises from losing some cancellation laws due to failing divergence free condition of the discrete velocity function. This result will be extended to Boussinesq equations in the continuous research (part II) and is essential in the study of part II.

• Restorative Dentistry and Endodontics
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• 제46권1호
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• pp.14.1-14.7
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• 2021

Objectives: The aim of this study was to evaluate the apical pressure generated by 2 endodontic irrigation needles and the GentleWave system in mandibular molars. Materials and Methods: The mesial and distal root canals of 12 mandibular molars were irrigated with a 30-gauge close-end needle or with a 30-gauge open-end needle. Procedures were performed in the mesial and distal canals. The GentleWave procedure and irrigation at 1 mm from the apex in the distal roots using an open-end needle were used, respectively, as negative and positive controls. The apical pressure was measured using a data acquisition pressure setup. Apical pressure exerted by the different needles in the 2 different canal types was statistically compared using 2-way analysis of variance. Results: Significant differences were found in the apical pressure for both needles and the canal type. The lowest values were obtained with close-end needles and in mesial canals. Negative apical pressure values were obtained using GentleWave. Conclusions: The needle and the canal type influenced the apical pressure. The GentleWave procedure produced negative apical pressure.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2002년도 유체기계 연구개발 발표회 논문집
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• pp.363-369
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• 2002

Orifice meter is the most widely used flowmeter in custody transfer between KOGAS and city gas companies. Absolute pressure value is needed to calculate the gas flow of orifice metering system, but the gauge pressure transmitters are mainly used in the field. In case that the gauge pressure transmitters are used, the fixed value as standard atmospheric pressure(101.325kPa) is applied for the absolute pressure value. The real, local atmospheric pressures of each metering station are different from the standard condition as the altitude and weather conditions. In this study the flow calculation errors were quantitatively analyzed through examining the atmospheric pressures of 50 stations of KOGAS. The data for analysis are such like the time data of supplied gas amount, the altitude of each metering station, the time data of atmospheric pressures and altitudes of each weather observatory. The results showed that the local atmospheric pressures were different from the standard value and the gas flow calculation errors were distributed between $-0.024\%{\~}0.025\%$ based on the supplied gas amount in the year 1999 and 2000.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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• pp.888-891
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• 2003

This paper describes on the fabrication and characteristics of micro ceramic thin-film type pressure sensors based on Ta-N strain-gauges for high-temperature applications. The Ta-N thin-film strain-gauges are deposited onto thermally oxidized Si diaphragms by RF sputtering in an argon-nitrogen atmosphere($N_2$ gas ratio: 8 %, annealing condition: $900^{\circ}C$, 1 hr.), Patterned on a wheatstone bridge configuration, and use as pressure sensing elements with a high stability and a high gauge factor. The sensitivity is $1.097{\sim}1.21mV/V.kgf/cm^2$ in the temperature range of $25{\sim}200^{\circ}C$ and the maximum non-linearity is 0.43 %FS. The fabricated pressure sensor presents a lower TCR, non-linearity than existing Si piezoresistive pressure sensors. The fabricated micro ceramic thin-film type pressure sensor is expected to be usefully applied as pressure and load sensors that is operable under high-temperature environments.

• 한국식품과학회지
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• 제22권6호
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• pp.686-689
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• 1990

김치의 발효상태를 monitoring할 수 있는 압력측정 sensor와 감시장치를 설계, 제작하였다. 본 시스템은 밀폐형 발효관(31.5 ml)과 strain gauge 타입의 압력 sensor, 741 Op. Amp.와 ADC0809를 사용하여 제작한 신호가공 장치로 구성하였으며 퍼스널 컴퓨터와 접속하여 사용하였다. 배추김치는 플라스틱 용기에 담가 $25^{\circ}C$와 $30^{\circ}C$에서 발효시켰으며 발효상태는 김치를 넣은 발효관으로 monitoring하였다. 압력곡선 형태의 김치발효 곡선을 얻을 수 있었으며 이는 2단 압력증가 양식을 갖는 김치숙성 곡선을 보여주었다.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2006년도 정기 학술대회 논문집
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• pp.71-76
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• 2006

In this paper, a long gauge Fiber Bragg Grating (FBG) sensor system is described and long gauge FBGs are well, suited for measuring the upper parts of the bridge piers under the extremely severe movement conditions. In the experiments, we used more than 30m long FBG sensors to measure the movement of top part of the bridge piers which are separated from the main bridge by cutting the decks. With the actuator, the deck and girders were pushed and released. We checked the movement of the top of the pier while releasing the pressure of the actuator with the long gauge fiber sensor. In order to measure the movement of the upper part of the pier, the reference point must be outside of the pier. Using the optical fiber sensors, one end of the sensor is attached to the top of the pier and the other end is attached to the bottom of the next pier. The fiber sensors showed good response to the release loading and we could calculate the movement of the top part of the pear.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1996년도 추계학술대회 논문집
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• pp.342-345
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• 1996

This paper presents the basic characteristics of thin-film strain gauges using Cr thin-films, in which the Cr thin-films were deposited by DC magnetron sputtering. The optimized deposition conditions as a strain gauge were the input DC power was 7 W/$\textrm{cm}^2$ and the Ar vacuuming pressure was 9 mTorr. The characteristics of fabricated Cr thin-film strain gauge were the gauge factor(GF) was 5.86 in longitudinal strain and -2.04 in transverse one, the TCR was under 400 ppm/$^{\circ}C$ and the TCS was around 0 ppm/$^{\circ}C$.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2006년도 추계학술대회 논문집
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• pp.1-6
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• 2006

The gauge - adjustable wheelset system in the transcontinental railway represents a more effective way in comparison with other techniques for overcoming difference in track gauges. Moreover, freight trains having the gauge - adjustable wheelsets will be run various curved tracks of Eurasian railroad network such as TKT, TCR and TSR. Therefore, to assure the safety of the gauge - adjustable adjustment wheelset system, it is necessary to evaluate durability of locking parts in the system during freight trains' service in the curved track. In this study, it was performed to estimate fatigue life of locking parts under lateral wheel pressure by using durability simulator.

• International Journal of Naval Architecture and Ocean Engineering
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• 제6권4호
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• pp.788-799
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• 2014

This study conducted four field measurements of local ice pressure during the icebreaking voyage of the icebreaking research vessel "ARAON" in the Chukchi and Beaufort seas from July to August of 2010. For measurements, 14 strain gauges, including 8 strain gauge rosettes, were set on the bow of the port side. Influence coefficients were determined using a finite element model of the instrumented area and they were used to convert the measured strains on the hull structure to local ice pressures. The converted maximum pressure was calculated as 2.12 MPa on an area of $0.28m^2$. Pressure-area curves were developed from the surveyed pressure data and the results were compared with previously measured data. The study results are expected to provide an understanding of local ice pressures and thus be useful in the structural design of ice class ships.