• Particle and aerosol research
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• v.11 no.2
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• pp.37-46
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• 2015

Dust particles, which inflow to the subway mechanical ventilation and air conditioning(MVAC) chamber, contain a fair amount of iron compounds, approximately 25.2w/w%. This work attempted to capture those iron containing dust using magnetic filters. Average magnetization value of the test MVAC dust was 0.012 emu on 5,000 Oe, which could correspond sufficiently with the magnetic interaction. External permanent magnets provided with magnetization of iron mesh screen showing high gradient magnetic field(HGM). It resulted in the capture efficiency with 84.0 ~ 99.7% and 81.2 ~ 99.8% for $PM_{10}$ and $PM_{2.5}$ respectively. Magnetic capture was found to be closely associated with the magnetic intensity, mesh opening size and flow velocity.

• Proceedings of the KSME Conference
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• 2000.04b
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• pp.353-358
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• 2000

This paper presents the experimental investigation about miniature heat pipe for notebook PC. The focus of analysis is the operating temperature not to exceed $65^{\circ}C$ maximum allowable CPU surface temperature. Copper is used to heat pipe material and brass is wick material, and working fluid is selected to water. This cooling system is heat spreader method using a aluminum plate, since this method is most commonly used. According to the present study, heat for 3mm heat pipe, 8W, and for 4mm heat pipe, 10W, is found to power dissipation limit respectively, Soon after this investigation, sufficient long term life test should be followed.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.643-646
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• 2002

Sealing of two glass plates composing of PDP panel was done in a vacuum chamber by using an auxiliary heating line(AHL). In order to improve the uniformity of sealing temperature and reduce the panel temperature during sealing, the AHL was introduced by a screen printing method inside a frit glass and used as a part of heating source for the frit melting. By using the AHL technology and the specially prepared frit glass, we have successfully sealed a PDP test panel without bubbles and any leak through the frit glass.

• Proceedings of the KIEE Conference
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• 1999.11d
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• pp.1105-1107
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• 1999

The purpose of termination for high voltage tests of XLPE power cable is to prevent flashover during the breakdown test of specimen as well as to withstand the specified voltage between its conductor and screen without failure. For easier treatment and simpler construction of testing termination, resistivity grading method using semi-conductive material was employed. Based on the fundamental theory, its failure characteristics by changing the resistivity of semi-conductive material on the insulation surface was investigated. With two layers construction by difference resistivity on their surfaces, much improved result than that of one resistivity was obtained through the experiment for MV cable.

• Proceedings of the Korean Society of Food Science and Nutrition Conference
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• 2003.11a
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• pp.74-77
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• 2003

A new health paradigm may be evolving that would place emphasis on the positive aspects of diet, identifying components that are physiologically active and that contribute to the prevention of disease onset. It has been increasingly difficult to evaluate the impact of new bioactive materials and food products on the well being of society. Thus, testing systems for both health function and toxicity have become very elaborate, complex, and interrelated, making their interpretation difficult and open to controversy. To select the proper starting materials, to screen the appropriate health functionality and to determine the efficacy of product, a reliable, reproducible, sensitive and predictive assay is required. Particularly, in uitro assay is the first stage in preclinical test on physiologically active materials and have many advantages in terms of time, cost and convenience. However, several factors as well as some limitations should be considered in this assay system. This presentation, therefore, will address the use of in uitro assays for evaluating physiological functionality of foods coupled with general consideration.

• Proceedings of the KSPS conference
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• 2000.07a
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• pp.241-254
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• 2000

The past decade has witnessed the abundant use of computer in testing language skills such as listening and reading. Compared with these language skills, we have experienced little use of computer in testing a speaking skill including pronunciation. This is largely due to limitations of the current computer technology. One of such limitations for testing pronunciation is to store and automatically evaluate what the learner utters. Due to this limitation, the computer simply stores what the learner utters and raters evaluate it afterward on a certain rating continuum. With the advent of voice recognition technology, however, the computer has been able to test pronunciation in a systematic way. This technology enables the computer to identify, visually show, and evaluate the learner's intonation pattern by means of autocorrection. The evaluation is expressed in terms of the degree in which the learner's intonation pattern overlaps with that of the native speaker of the target language. In particular, the degree is numerically displayed on the screen, and this numeral is considered as the score of the learner's utterance under our testing framework.

• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.202-202
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• 2000

AC-PDP(Plasma Display Paner)는 기체 방전을 이용한 디스플레이로서 기체에 직접 노출되는 MgO 보호막의 2차전자 방출계수(${\gamma}$는 AC-PDP의 방전특성을 결정짓는 중요한 요소이다. MgO 보호막의 이차전자 방출계수는 AC-PDP에 주입하는 기체의 종류, 결정 방향성과 표면오염상태 등에 영향을 받는다. 본 연구에서는 유리 기판위에 Al 전극을 증착, 에칭후 screen printing으로 유전체를 도포, 소성 한 21inch 규격의 test panel에 MgO 보호막을 E-Beam으로 5000$\AA$ 증착한 후 MgO 보호막을 대기에 노출되는 시간간격을 변수로 하여 대기 열처리 한 MgO보호막의 2차 전자방출계수를 ${\gamma}$-FIB(Focused Ion Beam) 장치를 이용하여 측정하였다. 그리고 대기 노출 간격은 1분, 5분, 20분으로 하여 2차 전자방출계수를 측정하였고, 2차전자방출계수 측정 시 가속전압은 50V에서 200V까지 변화를 주었으며, Ne+을 사용하여 1.2$\times$10-4Torr의 진공도를 유지하며 측정하였다. 또한 각각의 MgO막의 에너지 갭을 광학적 방법을 이용하여 구하였다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.37-41
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• 2002

This study has been focused on the development of an open architecture CNC system and integration of core application technology for machine tool such as a remote monitoring/diagnosis system, NURBS interpolation, and cutting process simulation. To do this, we have developed a comprehensive CNC software including the basic HMI, screen editor, ASF, and visual builder. As a control hardware system for machine tool, the universal I/O module and CNC main unit have been developed. Then the remote monitoring/diagnosis system and NURBS interpolation have been implemented in the CNC software. The cutting simulation software will be used for enhancing the productivity of machine tools. Through a simulator and test bed, the whole technology has been verified.

• Journal of Korean Society of Water and Wastewater
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• v.25 no.4
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• pp.519-525
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• 2011

We studied on the effect of faucet cleanliness, faucet conditions (screen, mixing faucet), and flushing time for bacterial detection in tap water. As results, tap water should be left to run to waste for 2 to 3 minutes and if a questionable cleanliness is questionable, disinfect the faucet by using flaming or other methods before sampling. We proposed sampling method to decrease effect of factors associated with bacterial detection in tap water and contributed to be evaluated more accurate water quality.

• Journal of the Korean Wood Science and Technology
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• v.24 no.2
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• pp.42-45
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• 1996

A residue from the newsprint waste was investigated as a filler in adhesive for bonding southern pine plywood. The residue was prepared by drying the wet residue to 8% moisture content and grinding the dry material using a laboratory Wiley mitt with a 75-${\mu}m$(200-mesh) screen. The residue was compared to a commercial filler commonly used in structural plywood adhesives. A total of 48 three-ply panels. 12.7mm nominal thickness and 0.3 by 0.3 m in size, were fabricated at two press times(4 and 5 min) and three assembly times(20, 40 and 60 min). Evaluations of the residue were carried out by performance tension shear tests after two 4-hour boil accelerated aging tests on plywood. The test results included tension shear strength and estimated wood failure values. All plywood made with the residue filler were comparable to the control-bonded plywood. These results indicate that residue from the newsprint waste streams would be suitable as filler for plywood adhesives.