• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 D
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• pp.2591-2593
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• 2005

본 연구는 물체의 좌우측 상단에 연결된 와이어로프를 모터 및 드럼을 통하여 감아 올리거나 내려 놓는 과정에서 물체가 수평상태를 유지하여 이동될 수 있도록 Two Motor-Two Drum 형식의 권양기를 제어 하는 권양기의 밸런스제어장치에 관한 것이다. 본 연구에 Two Motor-Two Drum 형식의 권양기 제어장치에 있어서, 물체의 상단에 연견된 일측 와이어로프와 타측 와이어로프의 이동길이를 실시간으로 검출하는 와이어로프 이동길이검출부와, 이 와이어로프 이동길이검출부를 통하여 검출되는 일측 와이어로프와 타측 와이어로프의 이동길이를 비교하여 물체의 기울어진 좌 우 편차를 검출하는 편차검출부와, 이 편차검출부를 통해 검출되는 좌우 편차를 제거하기 위하여 일측 또는 타측 와이어로프가 감겨있는 드럼을 회전시키는 모터의 구동속도를 조절하여 물체를 수평상태로 보정하는 밸런스제어부로 구성 되어 있다.

• 자연과학논문집
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• 제18권1호
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• pp.29-38
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• 2007

호 알칼리성이며 고온성인 Bacillus cereus TA-11이 세포내로 생성하는 invertase의 생합성 조절 양상을 조사하였다. Bacillus cereus TA-11의 세포내 invertase는 10 mM sucrose의 180분 처리와 25 mM raffinose의 90분 처리에서 각각 효율적으로 유도되었다. 또한 glucose는 sucrose에 의한 invertase의 유도를 억제하였고 cAMP첨가는 catabolite repression을 감소시키지 못하였다.

• 한국컴퓨터정보학회지
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• 제14권2호
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• pp.123-127
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• 2006

이 논문에서는 현재 모바일 단말기 중 국내에 가장 많이 보급되어 있는 휴대폰을 이용하여 가정 내에 위치하고 있는 여러 가전 기기를 원격에서 또는 가정 내에서 안전하게 모니터링하고 제어할 수 있는 원격 제어 홈 게이트웨이 시스템을 설계 및 구현하였다. 제안한 시스템은 디지털 가전기기 및 디바이스들과의 Zigbee 통신을 지원하며 Linux 환경의 셋톱박스 내의 흠 서버는 네트워크를 통해 외부 휴대폰과 통신하여 원격지에서 가정내의 디바이스들의 상황 정보를 확인하고 상태를 변경할 수 있도록 설계함으로써 홈 오토메이션 홈 네트워크, 스마트오피스 등의 실내 환경 및 다양한 유비쿼터스 환경에서 홈 네트워크 미들웨어로 적용될 수 있을 것으로 보인다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2011년도 춘계학술발표대회
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• pp.30.1-30.1
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• 2011

Multiferroic thin films with composition $0.9BiFeO_3-0.1Ba(Cu_{1/3}Nb_{2/3})O_3$ were epitaxially grown by pulsed laser deposition on $SrRuO_3(001)/SrTiO_3$ (000) substrate $0.9BiFeO_3-0.1Ba(Cu_{1/3}Nb_{2/3})O_3$, which is assumed to be morphotropic phase boundary (MPB), that showed superior dielectric, ferroelectric and magnetic properties in our study on polycrystalline films. The structures of epitaxially grown films were characterized by means of XRD. From P-E measurements, samples exhibited typical ferroelectric hysteresis loops and large remnant polarization, whose value is much larger than those of pure BFO film. The enhancement of dielectric, ferroelectric, magnetic properties was attributed to the structural distortion induced by the BCN addition and the high physical stress effect.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2006년도 춘계학술대회 논문집
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• pp.363-366
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• 2006

The delivery system such as sprue, runner and gate is a waste of resin in injection molding operation. In this study the reduction of runner size has been investigated using injection molding CAE softwares, Moldflow and Moldex, and commercial CFD Softwares, Fluent and Polyflow. To verify the computational results experiment was performed. There were three considerations in deciding optimal runner size in this study: minimum pressure at the gate that makes resin fully filled in the cavity, minimum runner size that compensates shrinkage of resin in the cavity, and frozen layer thickness formed in the runner during injection. Through the computer simulations the optimal runner size that satisfies those three considerations has been decided. Although the computational results among the softwares were slightly different, it was enough to predict, the optimal runner size. The previous runner diameter was 8 mm and predicted optimal size was 5 mm. This was verified by injection molding experiment. Thus, the way of CAE application in deciding optimal runner size adapted in this study would be appropriated.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 춘계 학술발표회
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• pp.448-456
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• 2010

The mechanical behavior of granular soils is affected by particle bonding including natural cementation. This study addresses a simple model of small strain stiffness and salt concentration based on wave measurements of salt-cemented particulate media. Published models of artificially cemented soils with different curing methods and several types of cementation agents are reviewed. Glass beads with the median diameter of D50 = 0.5mm are prepared in rectangular cells using the water-pluviated method in salt water with different concentrations. Piezo disk elements and bender elements embedded in the cell are used for the measurements of compressional and shear waves. The relationships between elastic wave velocities and salt concentration show an exponential function. The measured small strain stiffness matches well the predicted small strain stiffness based on micromechanics for simple cubic monosized sphere particles. This study demonstrates that the salt concentration in salt-cemented specimen may be evaluated by using elastic wave velocities.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 춘계 학술발표회
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• pp.607-614
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• 2010

Shear behavior of granular soils largely affects the safety and stability of underground and earth structures. This study presents the characteristics of shear zone in a direct shear test using shear wave and electrical resistivity measurements. An innovative direct shear box made of transparent acrylic material has been developed to prevent direct electric current. Bender elements and electrical resistivity probe are embedded in the wall of direct shear box to estimate the shear wave velocities and the electrical resistivity at the shear and non-shear zones. Experimental results show that the void ratio and shear wave velocity at shear zone increase during shearing while the values remain constant at non-shear zone. The results demonstrate correlation among the contact force, small strain shear modulus, and void ratio at shear zone. This study suggests that the application of the modified direct shear box including shear wave and electrical resistivity measurements may become an effective tool for analyzing soil behavior at shear zone.

• Journal of Radiation Protection and Research
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• 제27권2호
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• pp.89-94
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• 2002

IAEA 안전시리즈 109에 제시된 정당화 및 최적화 절차에 따른 비용-이득 접근법을 적용하여 우리나라에 적합한 방사선비상시 식품섭취제한 개입준위 값을 제안하였다. 관심 핵종은 예탁유효선량 기여도를 고려하여 세 그룹으로 구분하였고 대상식품은 가격에 따라 두 그룹으로 분류하였다. 아울러 제안된 개입준위를 실제 상황에 적용함에 있어서 고려해야할 사항에 대해 논의하였다.

• 한국세라믹학회지
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• 제47권2호
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• pp.195-198
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• 2010

It has been considered to apply GDC ($Gd_{0.1}Ce_{0.9}O_{1-X}$) for low-temperature SOFC electrolytes because it has higher ionic conductivity than YSZ at low temperature. However, open circuit voltage with using GDC ($Gd_{0.1}Ce_{0.9}O_{1-X}$) electrolyte in SOFCs, becomes lower than using YSZ (8 mol% Yttria stabilized Zirconia) electrolyte because GDC has electronic conductivity. In this work, the effect of changing GDC electrolyte thickness on the open circuit voltage has been investigated. Ni-GDC anode-supported unit cells were fabricated as follows. Mixed NiO-GDC powders were pressed and pre-sintered at $1200^{\circ}C$. And then, GDC electrolyte material was dip-coated on the anode and sintered at $1400^{\circ}C$. Finally the LSCF-GDC cathode material was screen-printed on the electrolyte and sintered at $1000^{\circ}C$. Electrolyte thickness was controlled by the number of dip-coating times. Open circuit voltage was measured depending on electrolyte thickness at $650^{\circ}C$ and found that the thicker GDC electrolyte was, the better OCV was.

• 대한전기학회논문지:전력기술부문A
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• 제51권11호
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• pp.544-550
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• 2002

This paper describes a strategy of a daily optimal operational scheduling on the industrial cogeneration system. The cogeneration system selected to establish the scheduling consists of three units and several auxiliary devices which include three auxiliary boilers, t재 waste boilers and three sludge incinerators. One unit generated electrical and thermal energy using the back pressure turbine. The other two units generate the energy using the extraction condensing turbine. Three auxiliary devices operate to supply energy to the loads with three units. The cogeneration system is able to supply enough the thermal energy to the thermal load, however it can not sufficiently supply the electric energy to the electrical load. Therefore the insufficient electric energy is compensated by buying electrical energy from utility. In this paper, the evolutionary algorithms was applied to establish the optimal scheduling for the cogeneration systems. Also the GUI System was developed using established mathematics medeling and evolutionary algorithms in order that non-experts are able to establish operational scheduling. This results revel that the proposed modeling and strategy can be effectively applied to cogeneration system for paper mill.