• Journal of the Korean Institute of Telematics and Electronics A
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• v.29A no.1
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• pp.41-47
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• 1992

In SFB Process, after 110$0^{\circ}C$ annealing in wet OS12T(95$^{\circ}C$ HS12TO bubbling) atmosphere, the existence of the interfacial oxide film in micro-gap at Si-Si bonding interface was identified. The angle lapping/staining and SEM morphologies of bonding interface showed that the growing behavior of interfacial oxide made a contribution to eliminate the micro-gaps having a width of 200-300$\AA$. In case of the diodes composed of p-n wafer pairs made by SFB processes, the annealed one in wet OS12T atmosphere exhibited a dielectric breakdown phenomena of interfacial oxide at 37-40 volts d.c.

• Journal of the Korean Institute of Rural Architecture
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• v.18 no.1
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• pp.39-46
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• 2016

The purpose of this study is to clarify the actual conditions of the floor area of skilled nursing facilities in rural area. The thorough investigation and observation works were made from the viewpoints of floor area of the skilled nursing facilities. This article discusses about the basic condition and the floor area for daily living activities of the elderly in 3 skilled nursing facilities in west gyeongnam province. As the result, There is a wide gap between floor area ratio of skilled nursing facilities. The characteristics of the private establishment skilled nursing facilities in the west gyeongnam province were figured out through the analysis of spatial composition in skilled nursing facilities for the elderly. The skilled nursing facilities in west gyeongnam mainly focus on the living environment orientated toward the bedroom. The difficulty is to encourage the communication between the skilled nursing facility patients because the facilities are composed of small semi-public zone.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.14 no.11
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• pp.1182-1194
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• 2004

This paper addresses the application of an active magnetic bearing (AMB) system to levitate the elevation axis of an electro-optical sight mounted on a moving vehicle. In this type of system, it is desirable to retain the elevation axis in an air-gap between magnetic bearing stators while the vehicle is moving. To eliminate disturbance responses, a disturbance observer based sliding mode control is developed. This control can decouple disturbance observation dynamics from sliding mode dynamics and preserves the robustness of the sliding control. The sliding surfaces are designed in the consideration of scattering of received image. The proposed control is applied to a 2-DOF active magnetic bearing system subject to base motion. Along with experimental results, the feasibility of the proposed technique is illustrated.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.11a
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• pp.224-229
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• 1996

An experimental study on critical heat flux (CHF) and two-phase flow visualization has been performed for water flow in internally-heated, vertical, concentric annuli under near atmospheric pressure. Tests have been done under stable forced- circulation, upward and downward flow conditions with three test sections of relatively large gap widths (heated length = 0.6 m. inner diameter = 19 mm, outer diameter = 29, 35 and 51 mm). The outer wall of the test section was made up of the transparent Pyrex tube to allow the observation of flow patterns near the CHF occurrence. The CHF mechanism was changed in the order of flooding, chum-to-annular flow transition, and local dryout under a large bubble in churn flow as the flow rate was increased from zero to higher values. Observed parametric trends are consistent with the previous understanding except that the CHF for downward flow is considerably lower than that for upward flow.

• 한국초전도학회:학술대회논문집
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• v.10
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• pp.21-21
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• 2000

The Josephson Plasma resonance in single crystalling Bi2Sr2CaCu2O8 has been investigated at a microwave frequency of 35 GHz in a cavity resonator. A sharp resonance is observed in a perpendicular oscillating magnetic field. The former is independent of the sample dimension, shile the latter shift to higher field as the sample size L is reduced, and it disappears when L becomes smaller than the critical length. The longitudinal plasma mode is a Nambu-Goldston mode in a superconductor, the experimental distinction between the longitudinal and the transverse mode leads to the conclusion that the existence of the Nambu-Goldston mod as predicted by Anderson was experimentally confirmed by direct observation of the Josephson plasma resonance with longitudinal excitations. The finite gap found in Josephson plasma resonance also provides a direct proof of the Anderson-Higgs mechanism within the context of the spontaneously broken phase symmetry of the Gauge-field theory in a superconductor.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.39 no.9
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• pp.956-963
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• 1990

The general shapes of prebreakdown pulses in a discharge gap were calculated and the current pulses due to avalanche were detected in SF6 by changing the polarity of the protrusion placed on an electrode at pressures up to about 400 Kpa. The mathematical model of prebreakdown pulse development with a negative protrusion shows agreement with the observed pulses. No evidence of intense bursts of field-emitted electrons was observed. Breakdown probably results from a single avalanche developing to a critical size. However the calculated shape of prebreakdown current pulse does not agree with the observed pulses with a positive protrusion. The breakdown is preceded by multiple avalanche development at pressures less than about 200 Kpa. This observation has been interpreted as due to the formation of negative ions following photoionization in the gas which drift into the critical volume near a positive protrusion.

• The Journal of the Korea Contents Association
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• v.10 no.1
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• pp.87-93
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• 2010

This paper describes an improved location determination scheme based on the triangulation method calculating a target position. The proposed scheme uses coordinates of intersection points of three circles each generated by measurement of an observer. The target position obtained from the proposed scheme has higher accuracy not only at the vicinity, but also at the periphery of the observation area. The maximum error and the average error with the proposed scheme are reduced by 40.89% and 40.30%, respectively, with respect to conventional methods.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.1
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• pp.64.2-64.2
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• 2013

Korea Astnonomy and Space Science Institute (KASI) operates two solar radio observing facilities, the Korean station of the e-CALLISTO and the Korean Solar Radio Burst Locator (KSRBL). The e-CALLISTO station had suffered from tracking problem for past several years. Since 2011, KASI has developed a new tracking system, and recently the antenna has regained the its sun-tracking capability and full day-time coverage. The KSRBL also suffered from the control computer breakdown last year. After one year of operational gap, the KSRBL restored its normal daily observation. We also expanded the data server storage capacity, to store the full original data of 25 ms integration time and 0.25 MHz frequency resolution, amounting to about 80 GB per day.

• Journal of the Korea Convergence Society
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• v.5 no.3
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• pp.45-51
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• 2014

Computer science and computing technologies are applied into mathematical, science, medical, engineering and educational applications. The models are used to solve the issues in all the domains. Educational systems are used top down, bottom up, Gap Analysis model in the educational learning system. Educational learning process integrated with Lerner, content and the methodology. The Learners and content are same in the educational system or similar courses but the teaching methodologies are differing one with another. The determinations of teaching methodologies are based on the factors related to that particular model or subject. The learning model influencing determinations are made by the surveys, analysis and observation of data to maximize the learning outcome. This paper attempted to evaluate the SNE learners cognitive using NASA Scaling.

• Publications of The Korean Astronomical Society
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• v.11 no.1
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• pp.263-277
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• 1996

We have intensively carried out numerical calculations on flare predictions from the solar activity data for photospheric sunspots, chromospheric flare and plages, coronal X-ray intensities and 2800MHz radio fluxes, by using multilinear regression method. Intensities of solar flares for the next day have been predicted from the solar data between 1977-1982 and 1993-1996. Firstly, we have calculated flare predictions with the multilinear regression method, by using separate solar data in growth and decay phase of sunspot area and magnetic field strength from the whole data on solar activities. Secondly, the same operations as above have been made for the remaining data after removal of the data with large deviation from the mean calculated by the above prediction method. we have reached a conclusion that average hit ratio of correct predictions to total predictions of flares with class of M5 over has been as high as 70% for the first case and that of correct prediction number to total observation number has been shown as 61%.