• Journal of the Korean GEO-environmental Society
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• v.24 no.2
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• pp.5-12
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• 2023

In this study, the amount of heaving soil and the heave characteristics of the heaving soil generated at the actual site were quantitatively analyzed through DCM laboratory test construction. By reproducing a series of construction processes of the DCM method in a large-scale soil tank close to the actual site, the amount of heaving soil was predicted and the elevation characteristics such as elevation, diffusion range, diffusion angle and amount of elevation of the heaving soil were evaluated. As a result of the laboratory test construction, the actual elevation in terms of similarity within the DCM improvement section is 0~8.18m, and an average of 3.50m is observed. The actual diffusion range of the heaving soil converted to the similarity ratio is distributed from 28.0 to 38.0m on the left and right sides of the improvement section. The total amount of heaving soil calculated by the SUFFER program based on the results of the laboratory test construction is 19,901m³. Compared with the injected slurry amount of 16,992m³, the amount of heave compared to the injected amount is analyzed as 85.4%. The diffusion angle of DCM heaving soil, which analyzed the results of DCM laboratory test construction with the SUFFER program, is measured to be 30.0~38.0° at a depth of 50.0m, and is evaluated as an average of 34.0°. On the other hand, based on the DCM laboratory test construction and the analysis results using the program performed in this study, the amount of heaving soil at the DCM depths of 40.0m and 60.0m is predicted.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.10
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• pp.737-742
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• 2013

The purpose of this study was to remove sediments obtained from breeding ground using supersonics and micro-air flotation method. Sediments from Tongyong breeding grounds showed no contaminations of heavy metals but had great amount of organics. Thus, efficient removal of sediments was required to preserve water quality near breeding ground. Supersonics treatment for sediments was determined to be essential because higher removal efficiency of sediments was obtained when supersonics treatment was used. In addition, application of coagulants increased removal efficiency because its usage increased particle size of sediments, which enabled easy trapping of sediments particle into micro-air bubbles. Removal efficiency of sediments slightly decreased from 95.8% (1 g/L) to 83.9% (8 g/L) at the tests for different amount of sediments, but most of tiny particles were removed from water where sand size particles were left in the bottom of reactors.

• Digital Contents
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• no.3 s.142
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• pp.102-105
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• 2005

온라인을 통해 각종 정보를 검색, 이용하는 온라인 DB서비스시장이 폭발적인 성장세를 구가하고 있다. 또 가입자 확대와 고기능 단말기 보급에 기댄 모바일 DB서비스가 새로운 DB서비스 시장의 견인차로 부상하며 DB시장 확대를 부추기고 있다. 한국데이터베이스진흥센터는 데이터베이스 산업의 지속적인 성장과 육성지원을 위한 발판을 마련하기 위해 2004년 국내 데이터베이스산업 현황조사를 실시했다.이 결과를 토대로 데이터베이스산업을 위한 정책이나 기업의 사업계획수립에 필요한 기초통계자료에 도움이 되길 바란다.

• Defense and Technology
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• no.2 s.144
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• pp.70-73
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• 1991

일본은 전자산업의 탄탄한 기반을 토대로 하여 민수부문에서 세계 선두권을 확보하고 있으며, 이제는 방위부문에서도 두각을 나타내면서 군사강국으로 부상하고 있습니다. 또한 최근의 걸프(Gulf)전쟁에는 상당한 재정지원과 함께 수송기를 파견하는등 영향력을 발휘하고 있습니다. 이러한 흐름에 맞추어 주변국 자료제공의 일환으로 일본 자위대의 차기(1991-1995) 중기 방위계획(차기방)의 개요를 살펴보았습니다

• Journal of the Korean Institute of Gas
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• v.13 no.3
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• pp.33-42
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• 2009

A numerical analysis of reactive flow in a liftoff flame is accomplished to elucidate the characteristics of liftoff flame. To verify reliance of numerical calculation, the liftoff heights of liftoff flame for various fuel exit velocities are compared between the existing experimental research results and the present calculation results. The flame propagation velocity is conducted at the flow redirection point which is on a stoichiometric line ahead of flame front. This point was selected constant distance from triple point regardless of fuel exit velocity at the previous research. This causes considerable errors for the flame propagation velocity and scalar dissipation rate. The main issue of the present research is to establish the resonable method to select the redirection point and so that to clarify the relationship between flame propagation velocity and scalar dissipation rate, which is the core properties in a triple flame stability.

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.679-681
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• 2002

본 논문에서는 해석적 기법을 적용하여, 추진력과 부상력을 동시 제어하는 Planar Motor의 정밀 특성 해석을 나타내었다. 특히, 본 해석 모델은 가동자의 요크를 제거하기 위한 Halbach Array를 적용하였으며, 이에 대한, 정밀한 특성 해석을 위해 공간고조파 해석법도 제안한다. 또한, 해석해 검증을 위하여 유한 요소해석법에 의한 결과와 비교 분석을 하며, 이를 토대로 한 해석 모델의 동작 특성을 살펴본다.

• Science of Emotion and Sensibility
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• v.23 no.3
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• pp.37-46
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• 2020

This study was aimed at investigating the activities of a badminton club and designing smart wear to prevent sports injuries during badminton club activities. Everyone is familiar with sports in an aging society and clubs are gradually developing. Popular badminton club activities lead to frequent sports injuries, especially ankle injuries, which are a serious problem that hampers members' participation in sports. Therefore, this study aims to propose a prototype design for smart wear to prevent sports injuries, including ankle injuries. First, we identified the characteristics and considerations of members of badminton clubs, and the components of smart wear to prevent sports injuries. Second, members of the badminton clubs and an elite badminton player participated in a survey on the issues and requirements associated with wearing smart wear. Third, usage scenarios for smart wear were created based on literature reviews and the user assessment lists. Fourth, a prototype of the smart wear to prevent sports injuries including ankle injuries was created based on the scenarios. With the proposed smart wear, members of badminton clubs who may require assistance with sports injuries will be able to monitor said injuries, as well as their health condition, as avatars in visual games through a smart terminal. The visual game system will provide easier access to information about sports injuries and health. This smart sportswear will allow members of badminton clubs to prevent sports injuries and review their performance. This study can be utilized to design smart wear to prevent sports injuries and monitor sporting activities or bio-signals.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1990.10a
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• pp.193-198
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• 1990

전자기 베어링은 기계적 접촉이 없고 전기적 제어가 가능하여 최근 고속 정 밀 회전기에 사용되고 있다. 본 논문에서는 능동 자기베어링을 모형화하고 제어 이득에 따른 계의 안정성 판별 및 응답특성의 변화를 고찰하였다. 이를 토대로 두개의 반경방향 베어링과 회전체를 제작하고 아날로그 제어회로를 구성하여 안정되게 회전체를 부상시킬수 있었으며 이로부터 계의 응답특성 을 구하였다.

• Proceedings of the Korean Information Science Society Conference
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• 2001.04b
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• pp.175-177
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• 2001

최근에 웹(Web) 사용의 지속적이 증가로 인하여 정보가 급증하고, 이로 인하여 웹은 정보교환의 의미뿐아니라 정보 저장이라는 중요한 의미를 지니게 되었다. 하지만 현재 많은 웹 페이지들이 HTML(Hyper Text Markup Language)문서로 제작되어 있어 정보관리의 의미에서 많은 부족함이 있고 이를 보완하기 위한 방법 중에 하나가 구조적이고 기능적 언어로 부상하고 있는 XML(exTensive Markup Language)을 기반으로 하여 문서를 제작하거나 변환하는 것이다. 본 논문은 HTML문서를 XML문서로 변환하는데 있어HTML문서 구조를 분석하고 분석결과를 토대로 형성되는 웹 스키마(Schema)를 이용하여 구조 중심의 변환이 이루어지도록 하는 방법에 대해서 제안한다.

• The Journal of the Acoustical Society of Korea
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• v.22 no.5
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• pp.337-344
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• 2003

In DC/DC converter and VVVF inverter, which are the must dominant noise sources of Maglev train, noise is radiated from core and coil excited by MS(Magnetostriction). The main noise source of DC/DC converter is transformer whose spectrum shows strong peaks associated with harmonics of exciting frequency, On the other hand, LIM/VVVF noise is dominated by the harmonics of switching frequency, whereas harmonics of exciting frequency are not significant. As switching frequency is increased in VVVF inverter, it is shown that the harmonics are shifted to higher frequency range. If switching frequency is increased from 700㎐ to 2 ㎑, It is measured that noise can be reduced by 5 to 6 ㏈. Since complete mathematical description of MS phenomena is far beyond the present technology, vibration spectrum is investigated qualitatively in this paper, where effect of increasing switching frequency is confirmed.