• International Journal of Air-Conditioning and Refrigeration
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• 제12권4호
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• pp.206-213
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• 2004

Cycle test for developed phase change material (PCM) is necessary in order to assess the variation of latent heat, which decreases with time by deterioration. T-history method and measurement using heat-flux meter are appropriate for the cycle test in a tube filled with PCM because they do not need an extraction of sample in measuring heat of fusion. In the present study, these methods were applied to a PCM having a melting point below a room temperature, different to the past studies for PCMs melting above a room temperature. As a result of experiment using pure water as specimen, we can obtained rea-sonable values for heat of fusion.

• 설비공학논문집
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• 제15권7호
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• pp.604-610
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• 2003

Cycle test for developed phase change material (PCM) is necessary in order to analyze the variation of latent heat, which decreases with time by deterioration. 7-history method and measurement using heat flux meter are appropriate for the cycle test in a tube filled with PCM because they do not need an extraction of sample in measuring the heat of fusion. In the present study, these methods were applied to a PCM having a melting point below a room temperature, different from the past studies for PCMs melting above a room temperature. As a result of experiment using pure water as specimen, we can obtain reason-able values for heat of fusion by both methods.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2004년도 하계학술연구발표회 논문개요집
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• pp.242-243
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• 2004

• 한국생산제조학회지
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• 제5권1호
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• pp.27-32
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• 1996

This paper deals with the distributions of magnetic flux of an electro-magnetic chuck which is one of the most commonly used chucking attachments in a surface grinding machine. The measured results showed good correspondence with the theoretical results which were previously presented by the same author. The normal and tangential components of the magnetic flux density were measured using the gauss meter. The measured results indicated that the magnetic flux density was periodically changing over the transverse position to the magnetic pole. The normal component of magnetic flux decreases very rapidly for the increased z position.

• 한국연소학회:학술대회논문집
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• 한국연소학회 제26회 KOSCO SYMPOSIUM 논문집
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• pp.261-266
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• 2003

An experimental study has been conducted to evaluate the effects of $CO_{2}$ on heat transfer from hydrogen oxygen-enriched flame. Experiments were performed on flames stabilized by a co-flow swirl burner, which mounted on top of the furnace. Five composition conditions of oxidizer were chosen with replacing $N_{2}$ with $CO_{2}$. In a steady state, total and radiative heat flux rates from the flame to the wall of furnace has been measured using heat flux meters. Temperature distribution in furnace also has been checked. Increasing $CO_{2}$ ratio in the oxidizer, the dominant heat transfer mode was changed into convection from radiation. Temperature in the furnace decreased but total heat flux increased.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 A
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• pp.108-110
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• 1999

In this paper, approximate means of estimating the flux and torque levels in an induction motor is discussed. There exists several method that is used directly by flux meter and flux sensing coils in the airgap. Most of these methods are sensitive to motor parameter value changes. Also, the harmonics in the motor voltage and current due to the nonsinusodial inverter waveform cause errors in the estimated torque. Finally, this result is applicated in arch type linear induction motor for study of noise and vibration.

• 한국화재소방학회논문지
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• 제29권5호
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• pp.34-41
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• 2015

정상 및 비정상상태의 화재조건에서 설치가 용이하고 저가형인 판형 열유속계(PT)의 적용성에 대한 실험적 연구가 수행되었다. 열원으로서 적외선 복사 히터와 C3H8이 적용된 정사각형 버너가 사용되었다. PT의 상대적 측정 정확도는 Gardon-type 열유속 미터를 이용한 측정결과와의 비교를 통해 평가되었다. 정상 및 비정상상태의 화재조건에서 PT의 최적 크기 및 두께는 측정 정확도와 실용적 관점에서 각각 100 mm와 0.6 mm로 확인되었다. 이 결과들은 PT의 크기 및 두께의 변화에 따른 전도 열손실과 열관성에 의해 설명되었다. 또한 Slow보다 빠른 화재 성장속도의 조건에서 PT를 이용한 열유속 측정에는 상당한 주의가 요구됨을 확인하였다.

• Environmental Engineering Research
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• 제12권4호
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• pp.176-193
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• 2007

The ability to measure groundwater contaminant flux is increasingly being recognized as crucial in order to prioritize contaminated site cleanups, estimate the efficiency of remediation technologies, measure rates of natural attenuation, and apply proper source terms to model groundwater contaminant transport. Recently, a number of methods have been developed and subsequently applied to measure contaminant mass flux in groundwater in the field. Flux measurement methods can be categorized as either point methods or integral methods. As the name suggests, point methods measure flux at a specific point or points in the subsurface. To increase confidence in the accuracy of the measurement, it is necessary to increase the number of points (and therefore, the cost) of the sampling network. Integral methods avoid this disadvantage by using pumping wells to interrogate large volumes of the subsurface. Unfortunately, integral methods are expensive because they require that large volumes of contaminated water be extracted and managed. Recent work has investigated the development of an integral method that does not require extraction of contaminated water from the subsurface. We begin with a review of the significance and importance of measuring groundwater contaminant mass flux. We then review groundwater contaminant flux measurement methods that are either currently in use or under development. Finally, we conclude with a qualitative comparison of the various flux measurement methods.

• 마이크로전자및패키징학회지
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• 제18권3호
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• pp.53-57
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• 2011

In the modern packaging technologies highly condensed metal interconnects are typically formed by highcost processes. These methods inevitably require the precise controls of mutually dependant process parameters, which usually cause the difficulty of the change in the layout design for interconnects of chip to-chip, or chip-to-substrate. In order to overcome these problems, the unique concept and methodology of self-assembly even in micro-meter scale were developed. In this report we focus on the factors which influenced the self-formed bumps by analyzing the phenomenon experimentally. In case of RMA flux, homogenous pattern was obtained in both plain surface and cross-section surface observation. By using RA flux, the phenomena were accelerated although the self-formtion results was inhomogenous. With ussage of moderate RA flux, reaction rate of the self-formation was accelerated with homogeneous pattern.

• 천문학회지
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• 제46권2호
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• pp.65-74
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• 2013

We probe the feasibility of high-frequency radio observations of very rapid flux variations in compact active galactic nuclei (AGN). Our study assumes observations at 230GHz with a small 6-meter class observatory, using the SNU Radio Astronomical Observatory (SRAO) as an example. We find that 33 radio-bright sources are observable with signal-to-noise ratios larger than ten. We derive statistical detection limits via exhaustive Monte Carlo simulations assuming (a) periodic, and (b) episodic flaring flux variations on time-scales as small as tens of minutes. We conclude that a wide range of flux variations is observable. This makes high-frequency radio observations-even with small observatories-a powerful probe of AGN intra-day variability; especially, those which complement observations at lower radio frequencies with larger observatories like the Korean VLBI Network (KVN).