• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.5
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• pp.404-409
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• 2011

An amorphous $Ge_2Sb_2Te_5$ thin film is one of the most commonly used materials for phase-change data storage. In this study, $Au_x(Ge_2Sb_2Te_5)_{1-x}$ thin film amorphous-to-crystalline phase-change rate were evaluated in using 658 nm laser beam. The focused laser beam with a diameter <10 ${\mu}m$ was illuminated in the power (P) and pulse duration (t) ranges of 1-17 mW and 10-460 ns, respectively, with subsequent detection of the responsive signals reflected from the film surface. We also evaluated the material characteristics, such as optical absorption and energy gap, crystalline phases, and sheet resistance of as-deposited and annealed films. The result of experiments showed that the thermal stability of the $Ge_2Sb_2Te_5$ film is largely improved by adding Au.

• Journal of Korean Society for Atmospheric Environment
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• v.21 no.1
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• pp.83-96
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• 2005

The purposes of this study were to characterize the local levels of VOCs (volatile organic compounds), to develop source profiles of VOCs, and to quantify the source contribution of VOCs using the CMB (chemical mass balance) model. The concentration of VOCs had been measured every 6-day duration in the SRO monitoring site in the Yeosu Petrochemical Industrial Complex from September 2000 to August 2002. The total of 35 target VOCs, which were included in the TO-14 designated from the U.S. EPA, was selected to be monitored in the study area. During a 24-h period, the ambient VOCs were sampled by using canisters placing about 10 ～ 15 m above the ground level. The collected canisters were then analyzed by a GC-MS in the laboratory. Aside from ambient sampling at the SRO site, the VOCs had been intensively and massively measured from 8 direct sources and 4 general sources in the study area. The results obtained in the study were as follows; first, the annual mean concentrations of the target VOCs were widely distributed regardless of monitoring sites in the Yeosu Petrochemical Industrial Complex. In particular, the concentrations of BTX (Benzene, Toluene, Xylene), vinyl chloride were higher than other target compounds. Second, based on these source sample data, source profiles for VOCs were developed to apply a receptor model, the CMB model. Third, the results of source apportionment study for the VOCs in the SRO Site were as follows; The source of petrochemical plant was apportioned by 31.3% in terms of VOCs mass. The site was also affected by 16.7% from wastewater treatment plant, 14.0% from iron mills, 8.4% from refineries, 4.4% from oil storage, 3.8% from automobiles, 2.3% from fertilizer, 2.3% from painting, 2.2% from waste incinerator, 0.6% from graphic art, and 0.4% from gasoline vapor sources.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.460-463
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• 1997

One of the major problems in automation of soybean sprouter is watering method. This study was conducted solve this problem. The soybean sprouter consisted of three parts: water-receiving chamber with siphon, water spraying bowl and sprout cultivating bowl. It functions as automatic-watering without manpower and electric power, and is not noisy and has duration. Watering interval, watering time and amount could be controlled by regulation of dropping times/min from a tap. Chlorine contained in tap water is naturally decreased during its (water) storage in the water receiving chamber. Among three types of sprouter (siphon type, wet paper type and water pump type) the siphon type can be used at $25{\sim}30^{\circ}C$ that is the optimum temperature for soybean sprout.

• Journal of Biosystems Engineering
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• v.41 no.4
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• pp.365-372
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• 2016

Purpose: Tea is the most frequently consumed drink worldwide, next to water. About 75% of the total world tea production includes black tea, and withering is one of the major processing steps critical for the quality of black tea. There are two types of tea withering methods: physical and chemical withering. Withering can be achieved by using tat, tunnel, drum, and trough withering systems. Of these, the trough withering system is the most commonly used. This study focuses on the different types of withering, their effect on the various quality attributes of tea, and other aspects of withering methods that affect superior quality tea. Results: During physical withering, tea shoots loose moisture content that drops from approximately 70-80% to 60-70% (wet basis). This leads to increased sap concentration in tea leaf cells, and turgid leaves become flaccid. It also prevents tea shoots from damage during maceration or rolling. During chemical withering, complex chemical compounds break down into simpler ones volatile flavor compounds, amino acids, and simple sugars are formed. Withering increases enzymatic activities as well as the concentration of caffeine. Research indicates that about 15% of chlorophyll degradation occurs during withering. It is also reported that during withering lipids break down into simpler compounds and catechin levels decrease. Improper withering can cause adverse effects on subsequent manufacturing operations, such as maceration, rolling, fermentation, drying, and tea storage. Conclusion: Freshly harvested leaves are conditioned physically and chemically for subsequent processing. There is no specified withering duration, but 14-18 h is generally considered the optimum period. Proper and even withering of tea shoots greatly depends on the standards of plucking, handling, transportation, environmental conditions, time, and temperature. Thus, to ensure consumption of high quality tea, the withering step must be monitored carefully.

• International Journal of Highway Engineering
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• v.11 no.1
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• pp.25-36
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• 2009

Everyday congestion length (distance) and duration (time) data are collected and recorded in Expressway Traffic Information Center. These records are based on the information that the operators watch CCTV and decide traffic condition in order to present information about congestion on VMS. Using VMS message has some merits like that it doesn't need a great lot of cost to construct hardware such like FTMS because operators can check traffic condition by watching CCTV only. Of cause in the aspect of accuracy, using VMS message has the limitation that it is based on subject decision compared with FTMS. However, it can be said that the value of using VMS message is very large. The object of this study is to use the VMS information record (log file) usefully to provide information of traffic condition on expressway for users (drivers) without keeping the VMS information record in dead storage. To do so, in this research, congestion calculation method able to understand traffic congestion condition on expressway was developed.

• Journal of Chest Surgery
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• v.33 no.12
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• pp.929-934
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• 2000

배경: 기관의 동종이식편은 초냉동보관으로 생육성을 유지할 수 있으며 항원성이 줄어든다고 알려졌으나 냉동보관 온도 및 기간에 따른 항원성의 변화는 아직까지 명확히 밝혀져 있지 않다. 따라서 이번 연구에서는 냉동보관 온도의 차이 및 기간이 쥐 기관 동종이식편의 거부반응에 미치는 영향을 연구하였다. 대상 및 방법: 24개의 쥐 기관을 적출하여 12개씩 -8$0^{\circ}C$ 냉동고 및 -196$^{\circ}C$ 질소탱크에 각각 1, 3, 6개월씩 보관하였다. 냉동보관한 기관을 반으로 나누어 48마리의 쥐복강에 대망으로 감싼 다음 이식하였다. 1, 3, 5군은 -8$0^{\circ}C$ 냉동고에 각각 1, 3, 6개월씩 보관한 기관 동종이식편을 이식하였고 2, 4, 6군은 -196$^{\circ}C$ 질소탱크에 각각 1, 3, 6개월씩 보관한 기관 동종이식편을 이식하였다. 7군은 대조군으로 냉동보관하지 않은 동종이식편을 이식하였다. 이식후 14일째 이식된 동종이식편을 적출하여 간질조직의 단세포 침윤정도 및 내강 폐쇄 정도를 관찰하여 거부반응을 정도를 측정하였다. 결과: 7개 군 모두에서 중등도 이상의 심한 단세포 침윤을 보였으며 각군간의 통계학적인 차이를 보이지 않았다. 1, 2, 3, 4, 5, 6군에서 7군에서 보다 내강 폐쇄 정도가 적었으나 통계학적인 의의는 없었다. 모든 군에서 연골주위 단세포 침윤이 심한 경우에도 연골세포는 비교적 생육성을 잘 유지하고 있었다. 결론: 냉동보관 온도 및 보관 기간의 차이에 따른 동종이식편의 거부반응의 차이는 없었으며 모든 군에서 심한 거부반응을 보였다. 따라서 냉동 보관 쥐 동종이식편을 이용한 실험에서는 적절한 면역억제제의 사용이 필수적이라고 생각된다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.10a
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• pp.882-885
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• 2014

The duration and frequency of flooding and not last long, by the time climate change drought. The increased accordingly by reducing stream flow and year variation. This trend is expected to continue, and change towards a comprehensive analysis of such quantity, quality and management of water resources are managed. Flood warning system is called to perform them electronically to the management of water resources such as these to be in the organic water-related basic data acquisition, storage, processing and utilization. Can be divided into hydrological observations and flood warning systems alert system broadcast system. Hydrological observation system is the measurement from the hydrological stations (water level, rainfall, water) that can be observed hydrological status of the dam basin hydrological observation data transmitted to the central office, located at the dam monitoring and control system through a variety of networks including satellite, and the collected defined as the system that sent the K-water head office in 1 minute increments hydrological observation data. Headquartered in support of this decision. Dimensions of the dam are provided in addition to inward. Channeled through various hydrologic analysis and leveraging the data transfer. This paper looks at ways to build out hydrological observation system.

• Journal of Food Hygiene and Safety
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• v.36 no.6
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• pp.504-509
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• 2021

The objective of this study was to develop dynamic model to describe the kinetic behavior of E. coli in sliced smoked duck. E. coli was detected in 2 sliced smoked duck samples (16.7%) at 1.23 log CFU/g. The maximum specific growth rate (𝜇_max) of E. coli ranged from 0.05 to 0.36 log CFU/g/h, and lag phase duration (LPD) ranged from 4.39 to 1.07 h, depending on the storage at 10-30℃, and h₀ value ranged from 0.24 to 0.51. The developed model was validated with observed values obtained at 13℃ and 25℃. The model performance was appropriate with 0.130 of root mean squared error (RMSE), and the dynamic model also described properly kinetic behavior of E. coli in sliced smoked duck samples. These results indicate that E. coli can contaminate sliced smoked ducks and the models developed with the E. coli isolates are useful in describing the kinetic behavior of E. coli in sliced smoked duck.

• Nuclear Engineering and Technology
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• v.56 no.3
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• pp.993-1001
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• 2024

The TANDEM project is a European initiative funded under the EURATOM program. The project started on September 2022 and has a duration of 36 months. TANDEM stands for Small Modular ReacTor for a European sAfe aNd Decarbonized Energy Mix. Small Modular Reactors (SMRs) can be hybridized with other energy sources, storage systems and energy conversion applications to provide electricity, heat and hydrogen. Hybrid energy systems have the potential to strongly contribute to the energy decarbonization targeting carbon-neutrality in Europe by 2050. However, the integration of nuclear reactors, particularly SMRs, in hybrid energy systems, is a new R&D topic to be investigated. In this context, the TANDEM project aims to develop assessments and tools to facilitate the safe and efficient integration of SMRs into low-carbon hybrid energy systems. An open-source "TANDEM" model library of hybrid system components will be developed in Modelica language which, by coupling, will extend the capabilities of existing tools implemented in the project. The project proposes to specifically address the safety issues of SMRs related to their integration into hybrid energy systems, involving specific interactions between SMRs and the rest of the hybrid systems; new initiating events may have to be considered in the safety approach. TANDEM will study two hybrid systems covering the main trends of the European energy policy and market evolution at 2035's horizon: a district heating network and power supply in a large urban area, and an energy hub serving energy conversion systems, including hydrogen production; the energy hub is inspired from a harbor-like infrastructure. TANDEM will provide assessments on SMR safety, hybrid system operationality and techno-economics. Societal considerations will also be encased by analyzing European citizen engagement in SMR technology safety.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.6
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• pp.137-148
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• 2008

There have been many cases of using wetlands as an alternative in controlling stormwater, treating mining leachate, and agricultural discharge, and so on, recently. The reality is, however, that the wetlands are not properly applicable because of the lack of enough longterm data for wetlands due to the difficulty of long-term monitoring. Therefore, this study tries to analyze the storage of Upo, Mokpo, Sajipo, and Jjokjibeul in Topyeong watershed using SWAT(Soil and Water Assessment Tool) model, one of the long-term runoff hydrologic model, for the purpose of generating the long-term data and analyzing the hydrologic behavior of wetlands based on the generated data. Also, the changes in runoff at the outlet are analyzed after applying the simulation of constructing washland in Topyeong watershed and the storage in Upo is analyzed. The result shows that the runoff at the outlet of the watershed is decreased in rainy season from July to August and increased in dry season from December to February. In addition, the analysis of Upo storage concludes that Upo can be influenced by the construction of the washland. The duration curve of washland is then analyzed in order to evaluate the wetland's sustainability in terms of washland and it appears that the runoff of washland is simulated to be less than that of the existing wetland. Moreover, runoffs of some washlands are simulated to be less even in wet season. These results lead to the fact that there should be further hydrologic management for constructed washland. Then, the changes in loads (TN and TP) because of constructing washland are analyzed. The result shows that the loads are reduced because of the construction. Also, the changes in loads due to the construction of buffer strips are analyzed to compare the load reductions caused by a washland. Finally, REMM model, a riparian management model, is applied to overcome the hydrologic ambiguousness of SWAT model, and then, the SWAT model results are compared to those of REMM.