• Journal of Radiation Protection and Research
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• v.21 no.4
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• pp.313-327
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• 1996

As an at-reactor(AR) storage method o( spent fuel, there are horizontal concrete module type, metal storage cask type, concrete storage cask type, dual purpose (transportation and storage) cask type and multi-purpose (transportation, storage and disposal) cask type. All other types except multi-purpose one have been already used for AR dry storage of spent fuels after obtaining operation license in various foreign countries. Also the development of multi-purpose type has been continued for operation license. In America, Japan, Germany, Canada, Spain, Switzerland, and Czech Republic, etc., AR dry storage facilities are under operation or on propulsion, and spent fuels are transported to interim storage facility or reprocessing plant after dry storage at reactor temporarily. At Wolsung site, in case of Korea, concrete silo type has already been introduced, and it is believed to be inevitable to store spent fuels at reactor temporarily, considering the reality that storage capacity of spent fuel is approaching to the limit in some nuclear power plants. In this report, the system characteristics, design requirements, technical standards and status of AR storage system, which is suitable for domestic site such as Kori, have been studied. In most cases, the licensed period of storage cask is limited up to 20 years and the integrity of material and maintenance of leaktightness are required during the whole service life.

• Journal of the Korean Society of Visualization
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• v.18 no.2
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• pp.28-34
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• 2020

In this study, we numerically investigated the thermal stratification in solar seasonal thermal storage tanks. The vertical in/out flows were unsuitable for the thermal stratification in a large scale. The effect of an aspect ratio (AR) on the thermal stratification was investigated. When AR was less than 2, water adheres and flows along the upper wall due to buoyance and the surface effect. Thereafter, hot water flows down and a large scale vortex occurs in entire tank. For high AR, jet flows ejected from the inlet pipe impinges to the opposite wall and splits. The divided flows create two vortex flows in the upper and lower regions. These different flows strongly influence temperature and thermal stratification. The thermal stratification was evaluated in terms of the thermocline thickness and degree of stratification. Compared to ARs, the maximum degree of stratification was obtained with AR of 5 having the minimum thermocline thickness.

• Journal of the Korean Society of Visualization
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• v.19 no.3
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• pp.99-105
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• 2021

In this study, the thermal stratification in solar seasonal thermal storage tanks was numerically simulated. The effects of the aspect ratio (AR) and inlet velocity on the thermal stratification in the diffuser type heat storage tank were investigated. The temperature distributions inside the tank were similar with velocity fields. Jet flows from opposite diffusers encountered each other at the tank center region. Thereafter, the downward flows occurred, and this flows strongly affected the thermal stratification. When AR was smaller than 2, these downward flows influenced a further distance and enhanced mixing inside the tank. Thermal stratification was evaluated by thermocline thickness and degree of stratification, and AR of 3 had the highest degree of stratification. The inlet velocity effect was expressed with the ratio (Re/Ri) of Reynolds and Richardson numbers. The second-order approximation was found for the relationship between the thermocline thickness and log Re/Ri.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2015.10a
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• pp.341-342
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• 2015

• Journal of the Institute of Convergence Signal Processing
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• v.21 no.2
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• pp.67-72
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• 2020

AR service using the client-server method and existing physical markers(eg, OR Codes, etc.) causes a delay in the playback time of the contents because the contents download is executed after the marker recognition. In the case of the one-time installation method rather than the client-server method, proactive download of high-capacity contents for playback may cause an inefficiency of the storage space of the device(eg, smartphone, etc.). Therefore, in AR contents playback based on beacon's RSSI to secure the efficiency of the playback device storage space and to quickly play AR contents. The technique for high-speed playback in this study can be applied to various fields such as MICE exhibition using beacon signal.

• Proceedings of the KIEE Conference
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• 2006.07c
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• pp.1438-1439
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• 2006

$Ge_{2}Sb_{2}Te_5$(GST) thin film at present is a promising candidate for a phase change random access memory (PCRAM) based on the difference in resistivity between the crystalline and amorphous phase. PCRAM is an easy to manufacture, low cost storage technology with a high storage density. Therefore today several major chip in manufacturers are investigating this data storage technique. Recently, A. Pirovano et al. showed that PCRAM can be safely scaled down to the 65 nm technology node. G. T Jeonget al. suggested that physical limit of PRAM scaling will be around 10 nm node. Etching process of GST thin ra films below 100 nm range becomes more challenging. However, not much information is available in this area. In this work, we report on a parametric study of ICP etching of GST thin films in $Cl_2$/Ar chemistry. The etching characteristics of $Ge_{2}Sb_{2}Te_5$ thin films were investigated using an inductively coupled plasma (ICP) of $Cl_2$/Ar gas mixture. The etch rate of the GST films increased with increasing $Cl_2$ flow rate, source and bias powers, and pressure. The selectivity of GST over the $SiO_2$ films was higher than 10:1. X-ray photoelectron spectroscopy(XPS) was performed to examine the chemical species present in the etched surface of GST thin films. XPS results showed that the etch rate-determining element among the Ge, Sb, and Te was Te in the $Cl_2$/Ar plasma.

• Applied Biological Chemistry
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• v.37 no.1
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• pp.1-8
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• 1994

This study was carried out to investigate the changes in volatile constituents concerning with the flavor of the green ginger (Zingiber officinale Roscoe) during storage in underground pit ($15^{\circ}C$, RH 95%). And the constituents of essential oil of etiolated shoots formed on the mother rhizomes during the five months storage in the dark under same conditions were compared with those of mother rhizomes. The essential oils of Korean domestic ginger (Bong-dong cultivar) were isolated by simultaneous steam distillation and extraction method (SDE). Then the compositions of the essential oils were analysed by GC and GC-MS spectrometry. The major compounds of essential oil from the fresh rhizomes were zingiberene, $citronellol+{\beta}-sesquiphellandrene$, ${\beta}-phellandrene$, camphene, geranial, ${\gamma}-bisabolene$, ar-curcumene+geranyl acetate, ${\alpha}-pinene$, ${\beta}-gurjunene$, limonene and neral. The content of monoterpene hydrocarbons increased with a concomitant lowering in the amounts of sesquiterpene hrdrocarbons and oxygenated sesquiterpenes during storage of rhizomes although contents of the oxygenated monoterpens changed little or slightly during the storage. During the storage the content of such monoterpenes as camphene, ${\beta}-phellandrene$ and citral (neral and geranial) increased whereas the content of such sesquiterpenes as zingiberene and $citronellol+{\beta}-sesquiphellandrene$ decreased. The composition of shoot oil differed from that of mother rhizome oil in having higher content of terpene hydrocarbons and also in the higher content of bornyl acetate, ${\beta}-gurjunene$ and ar-curcumene+geranyl acetate and lower in citral (neral and geranial).

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.3
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• pp.762-767
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• 2013

Recently, researches on augmented reality(AR) are actively being conducted, and on addition of AR in social network system has become a necessity. In this paper, we propose GPS-based AR system for social network. This proposed system adds the recent check-in coordinates by automatically synchronizing a friend list in facebook and represents those added location coordinates in a real-world environment by using AR. Marker-based AR system that was commonly used by existing users consumes too much storage space and processing frequency for driving handle devices. But, location-based AR application can solves the disvantages of the standard marker=based AR system. Therefore, this proposed system allows an user with iOS hand devices to use GPS-based AR system by automatically searching the optimal speed for wifi and 4G. This will improve social network service.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.903-905
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• 2012

Recent research on Augmented Reality is Actively expand and Augmented reality feature added to the social network system (Social Network System) has become a necessity. In this paper, GPS-based Augmented Reality System for Social Network is introduced, is proposed. This system can add recent check-in friends in facebook by automatically to synchronizing the location coordinate, and it could also adding location coordinates system is represented in a real-world environment by AR, is Marker-based AR system that was Commonly used AR system is a huge cost by handheld devices in processing and storage space, the disadvantages of the marker-based AR systems can be solved by using Location-based AR applications. Therefore, the proposed GPS-based Augmented Reality System for Social Network, automatically searches for the optimal speed for Wifi and 4G network to iOS Hand AR system was desired in future.

• Food Science and Biotechnology
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• v.16 no.5
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• pp.817-821
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• 2007

The effect of acetylated rice (AR) starch at different concentrations (0, 4, 6, and 8%) on rheological properties of surimi sols and gels was studied. Dynamic frequency sweeps of surimi-AR starch sols at $10^{\circ}C$ showed that the magnitudes of storage moduli (G') decreased with an increase in starch concentration while those of tan ${\delta}$ increased, indicating that the effect of AR starch on the viscoelastic properties of surimi sols depended on starch concentration. In general, the G' thermograms of surimi sols showed the similar sol-gel transition pattern and they were also influenced by the addition of AR starch. The presence of AR starch in the surimi gel system reduced the gel strength and expressible moisture content (EMC). Surimi-AR starch gels showed better freeze-thaw stability compared to the control (0% starch concentration). The effect of AR starch on the rheological properties of surimi sols and gels appeared to be related to the swelling ability of starch granules in the presence of limited water available for starch.