• Journal of the Korean Magnetics Society
• /
• v.6 no.6
• /
• pp.375-381
• /
• 1996

This study is conducted to develop the high frequency inductor with ferro-yoke for the surface shape control. A 3- Dimensional simulation program based on the finite element method is developed for calculating electromagnetic field of the high frequency inductor. The validity of the program and the capability to control the liquid metal shape are confirmed by comparison between the results from calculation and those from measurement.

• Macromolecular Research
• /
• v.12 no.4
• /
• pp.427-430
• /
• 2004

Calix[4]crown-6-2,4-bis(2-hydroxyethyl ether) (2), which has crown-6 moieties at the 1- and 3-positions and hydroxyethyl functions at the 2- and 4-positions, was prepared for the syntheses of polyester 3 and polyurethane 4 by reactions with adipoyl chloride and hexamethylene diisocyanate, respectively. The ion binding characteristics of monomer 2 and polymers 3 and 4 toward alkali and alkali earth metal ions were measured by liquid-liquid extraction from the aqueous phase into the organic phase. We observed that the polyurethane 4 has a higher binding affinity toward various metal cations when compared to polyester 3, which exhibits cesium ion selectivity.

• Proceedings of the Korean Nuclear Society Conference
• /
• 1998.05a
• /
• pp.291-296
• /
• 1998

The DAta management and Communication NETworks (DACONET), Which it is designed as a subsystem for Man-Machine Interface System of Korea Advanced LIquid MEtal Reactor(KALIMER MMIS) and advanced design concept is approached, is described. The DACONET has its roles of providing the real-time data transmission and communication paths between MMIS systems, providing the quality data for protection, monitoring and control of KALIMER and logging the static and dynamic behavioral data during KALIMER operation. The DACONET is characterised as the distributed real-time system architecture with high performance, Future direction, in which advanced technology is being continually applied to Man-Machine interface System Development of Nuclear Power Plants, will be considered for designing data management and communication networks of KALIMER MMIS

• Proceedings of the Korean Nuclear Society Conference
• /
• 1998.05a
• /
• pp.118-123
• /
• 1998

The neurotics analysis of a liquid metal reactor fur burning minor actinides has shown that uncertainties in the nuclear data of several key minor actinide isotopes can introduce large uncertainties in the predicted performance of the core. A comprehensive sensitivity and uncertainty analysis was performed on a 1200 MWth actinide burner designed for a low burnup reactivity swing, negative doppler coefficient, and low sodium void worth. Sensitivities were generated using depletion perturbaton methods for the equilibrium cycle of the reactor and covariance data was taken ENDF-B/V and other published sources. The relative uncertainties in the burnup swing, doppler coefficient, and void worth were conservatively estimated to be 180%, 91%, and 46%, respectively.

• Nuclear Engineering and Technology
• /
• v.33 no.4
• /
• pp.423-440
• /
• 2001

For sodium cooling liquid metal reactors during the last 25 years, it was most important to verify the safety of the steam generator, which absolutely requires a water leak detection system with fine sensitivity and response. This study describes the structure and leak classification of the HAMMER (Korea Advanced Liquid Metal Reactor) steam generator, compared with other classifications, and explains the effects of leak development. The requirements and experimental situations for the development of the KALIMER acoustic leak detection system (KADS) which detects micro leaks, not intermediate leaks, are introduced. We proposed four frequency bands, 1∼8kHz, 8∼20kHz, 20∼40kHz and 40∼200kHz, split effectively for analyzing the detected acoustic leak signals obtained from the sodium-water reaction model or water model in the mock-up system.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2013.02a
• /
• pp.97-97
• /
• 2013

The exterior structures of natural organisms have continuously evolved by controlling wettability, such as the Namib Desert beetle, whose back has hydrophilic/hydrophobic contrast for water harvesting by mist condensation in dry desert environments, and some plant leaves that have hierarchical micro/nanostructures to collect or repel liquid water. In this work, we have provided a method for wettability contrast on metals by both nano-flake or needle patterns and tuning of the surface energy. Metals including steel alloys and aluminum were provided with hierarchical micro/nanostructures of metaloxides induced by fluorination and a subsequent catalytic reaction of fluorine ions on metal surfaces in water with various ranges from room to boiling temperature of water. Then, a hydrophobic material was deposited on the structured surfaces, rendering superhydrophobicity. Plasma oxidization induces the formation of superhydrophilic surfaces on selective regions surrounded by superhydrophobic surfaces. We show that wettability contrast surfaces align liquid water within patterned hydrophilic regions during the condensation process. Furthermore, this method could have a greater potential to align other liquids or living cells.

• Transactions of the Korean Society of Pressure Vessels and Piping
• /
• v.7 no.3
• /
• pp.30-39
• /
• 2011

URANUS (Ubiquitous, Robust, Accident-forgiving, Non-proliferating, Ultra-lasting and Sustainer) has been developed with 35MWe (100MWth) operating without primary coolant pump, capitalizing on natural circulation capability of lead-bismuth eutectic (LBE) for long-life small and robust power units. To ensure the structural integrity, the large safety margin against Safe Shutdown Earthquake, 0.3g, and furthermore the cost effectiveness for URANUS, three-dimensional seismic base isolation design has been developed. The analytical model has been developed and seismic time history analyses have been carried out. The advantage for using three-dimensional seismic base isolation for URANUS has been discussed.

• Journal of Korea Foundry Society
• /
• v.30 no.5
• /
• pp.187-195
• /
• 2010

In this study, in order to obtain a useful guide line for design and production of automotive heat exchanger components made of 4343/3003/4343 aluminum clad sheets, it was aimed to improve the understanding about the grain refinement effect on brazing characteristic of the clad sheets. Al-10Ti master alloy was used for grain refinement of 3003 core alloy, and the Ti inoculation level was systematically changed up to 0.1 wt%. The three-layer aluminum clad sheets were fabricated by hot roll bonding process. The effect of grain refinement on brazing characteristic of the clad sheets was investigated by evaluating wettability, bonding strength and sagging resistance.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 2005.05a
• /
• pp.360-363
• /
• 2005

본 연구에서는 인듐 액체금속이온원을 제작하여 빔 특성에 대해 연구를 하였으며, 기존의 연구를 하였던 갈륨 액체금속 이온원의 빔특성과 비교분석 하였다. 빔특성 분석을 위해 빔 안정도, 전류-전압특성곡선, 에너지 퍼짐을 측정하였다. 액체금속이온원에 사용되는 액체금속 저장소 및 바늘전극(tip)은 $500{\mu}m$의 직경을 갖는 텅스텐을 사용하였으며, 국내에서 제작된 제품을 사용하였다. 액체금속 저장소의 구조는 이전에 구상하여 연구가 이루어진 6개의 pre-etching된 텅스텐와이어(wire)가 묶여진 형태를 사용하였다.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
• /
• 2003.12a
• /
• pp.45-49
• /
• 2003

본 논문에서는 gate 산화막을 위한 Hf oxide 박막을 $Hf(dmae)_4$ (dmae=dimethylaminoethoxide) 전구체로 Direct Liquid Injection Metal Organic Chemical Vapor Deposition (DLI-MOCVD)방법을 이용하여 p-type Si(100) 기판 위에 증착하였다. 이 전구체를 이용하여 $150^{\circ}C$의 낮은 증착 온도에서도 낮은 carbon 농도와 roughness를 가지는 양질의 박막을 증착할 수 있었다. 증착된 박막은 비정질 구조를 나타내었지만 annealing 온도를 증가시킴에 따라서 결정성(monoclinic phase)을 나타내었다. $500{\AA}$으로 증착한 박막을 C-V 와 I-V curve를 통하여 전기적 특성을 평가하였다. 열처리 온도가 증가함에 따라 유효유전상수(k)는 증가하지만 열처리 온도가 $900^{\circ}C$ 이상이 되면 계면층의 형성에 의해 유효유전상수는 감소하게 되고 이에 따라 누설 전류도 감소하게 된다. 산소분위기 $800^{\circ}C$에서 annealing한 $HfO_2$ 박막의 유전상수는 20.1이고, 누설 전류 밀도는 SV에서 $2.2\times10^{-6}A/\textrm{cm}^2$ 로 좋은 전기적 특성을 가진다.