• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.738-742
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• 2003

In order to estimate the mass transfer characteristics of absorption into alcohol solution of aroma compounds such as cineol, myrecene and pinene which are major aroma compounds of rosemary, dimensionless Henry's constant in 70% ethyl alcohol concentration and aroma concentration with different ethyl alcohol concentration were analyzed. From the results of measurement of vapor phase concentration of aroma compounds with different ethyl alcohol concentration, headspace concentrations of all of three aroma compounds were decreased as ethyl alcohol concentration increased. But those patterns were slightly different. Dimensionless Henry's constant equation (Hi) of cineol compound with ethyl alcohol concentration (x) was as follows: $Hi=(-5.75+x)/(-7017.6+257.3{\times}x)$. Dimensionless Henry's constants of cineol, myrecene and pinene in 1 atm, $25^{\circ}C$ and 70% ethyl alcohol concentration were 0.0058, 0.0182 and 0.0365, respectively.

• Journal of Animal Environmental Science
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• v.9 no.2
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• pp.69-78
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• 2003

In this study, the energy conversion equipment from the radiation energy to mechanical energy by using n­pentane as the operating fluid was constructed and the performance to pump the water was tested for the utilization of solar powered water pump. The equipment was designed optimally, after the theoretical analyses of the water pumping head and water quantity per cycle were done. The pentane vapour temperature in the condenser and the temperature of the outlet water from the condenser became lowered and the heat transfer rate became higher with decreasing the water inlet level to the condenser. The temperature difference between the condenser and the water tank was significant. Therefore, the distance between the water tank and condenser was recommended to be shorten and the diameter of their connecting pipe was recommended to be narrow in order to reduce the resistance of the fluid passage and improve the heat transfer rate. The amount of water pumped was 1.6­2.4 liters. Mass flow rate of the cooling water became lowered when the cooling water pipe was prolonged from the condenser to improve the heat transfer rate.

• Journal of Animal Environmental Science
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• v.10 no.3
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• pp.141-154
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• 2004

The solar powered water pump is very ideal equipment because solar power is more intensive when the water is more needed in summer and it is very helpful in the rural area, in which the electrical power is not available. The average so]ar radiation energy is 3.488 kWh/($m^2{\cdot}day$) in Korea. In this study, the automatic control logic and system of the water pump driven by the radiation energy were studied, designed, assembled, tested and analyzed for realizing the solar powered water pump. The experimental system was operated automatically and the cycle was continued. The average quantity of the water pumped per cycle was about 5,320 cc. The cycle time was about 4.9 minutes. The thermal efficiency of the system was about $0.030\%$. The pressure level of the n-pentane vapour in flash tank was 150$\%$450 hPa(gauge) which was set by the computer program for the control of the vapour supply. The pressure in the condenser and air tank during cycles was maintained as about 600 hPa and 1,200 hPa respectively. The water could be pumped by the amount of 128kg/($m^2{\cdot}day$) with the efficiency of $0.1\%$ and the pumping head of 10 m for the average solar energy in Korea.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.77-77
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• 2016

Thin films synthesized by plasma processes have been widely applied in a variety of industrial sectors. The structure control of thin film is one of prime factor in most of these applications. It is well known that the structure of this film is closely associated with plasma parameters and species of plasma which are electrons, ions, radical and neutrals in plasma processes. However the precise control of structure by plasma process is still limited due to inherent complexity, reproducibility and control problems in practical implementation of plasma processing. Therefore the study on the fundamental physical properties that govern the plasmas becomes more crucial for molecular scale control of film structure and corresponding properties for new generation nano scale film materials development and application. The thin films are formed through nucleation and growth stages during thin film depostion. Such stages involve adsorption, surface diffusion, chemical binding and other atomic processes at surfaces. This requires identification, determination and quantification of the surface activity of the species in the plasma. Specifically, the ions and neutrals have kinetic energies ranging from ~ thermal up to tens of eV, which are generated by electron impact of the polyatomic precursor, gas phase reaction, and interactions with the substrate and reactor walls. The present work highlights these aspects for the controlled and low-temperature plasma enhanced chemical vapour disposition (PECVD) of Si-based films like crystalline Si (c-Si), Si-quantum dot, and sputtered crystalline C by the design and control of radicals, plasmas and the deposition energy. Additionally, there is growing demand on the low-temperature deposition process with low hydrogen content by PECVD. The deposition temperature can be reduced significantly by utilizing alternative plasma concepts to lower the reaction activation energy. Evolution in this area continues and has recently produced solutions by increasing the plasma excitation frequency from radio frequency to ultra high frequency (UHF) and in the range of microwave. In this sense, the necessity of dedicated experimental studies, diagnostics and computer modelling of process plasmas to quantify the effect of the unique chemistry and structure of the growing film by radical and plasma control is realized. Different low-temperature PECVD processes using RF, UHF, and RF/UHF hybrid plasmas along with magnetron sputtering plasmas are investigated using numerous diagnostics and film analysis tools. The broad outlook of this work also outlines some of the 'Grand Scientific Challenges' to which significant contributions from plasma nanoscience-related research can be foreseen.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.04a
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• pp.77-77
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• 1999

담배용 필터에 사용되고 있는 재료는 아세테이트, 종이, 폴리프로펼렌, 부직포등이 주로 이용되고 있으 며 담배연기의 흡착능을 향상시키기 위한 방법으로 활성탄 제오라이트와 같은 흡착제를 담배필터에 첨가하여 사용하고 있다. 본 실험에서는 펼터에 가장 보편적으로 많이 사용하고 있는 활성탄을 종이 제조과정에 첨가하여 나타나는 물리적 특성을 관찰하였고 제조된 종이를 담배필터에 적용하기 위하여 현행 습식 크림핑(crimping)방법과는 달리 건식 크림핑(crimping)방법을 이용한 적합한 조건을 검토하 였으며 이에 따른 담배필터에서의 연기흡착능을 분석한 결과는 다음과 같다. 1. 시트의 물리적 특성과 담배 연기성분 홉착능을 예측하기 위하여 펄프의 불성과 uv 홉착능을 분 석한 결과 Sw-BKP가 Hw-BKP에 비하여 강도적 성질이 우수하였고 또한 메틸렌불루(methylene b blue) 흡착능도 높은 경 향을 나타내 었다. 2. 활성탄 함량의 증가에 따라 섬유간의 결합력이 약화됨에 따라서 시트의 인장강도 및 파열강도가 감 소하는 경향이 가장 크게 나타났으며 평량이 펼프 배합비보다 높은 인자로 작용하였다. 또한 인자 간의 교호작용에서는 평량과 활성탄 함량에 따라서 크게 나타났으며 평량, Sw-BKP의 함량이 증가할 수록 인장강도는 증가하였다. 3. Stiffness는 활성탄 함량 펄프 배합비 평량의 순에따라 중요한 인자로 작용하였고 활성탄 함량 이 많을수록 stiffness는 감소하였으며 평 량 Sw-BKP의 함량이 높을수록 증가하였다 인자간의 교 호작용은 평량과 활성탄 함량이 다른 요인에 비하여 높은 경향을 보였다. 4. 인열강도는 활성탄 함량이 증가함에 따라 가장 크게 감소하였고 시트의 평량이 펄프 배합비보다 높은 인자로 작용하였으며 평 량 Sw-BKP의 함량이 높을수록 증가하였다 인자간의 교호작용에서는 펄프 배합비와 활성탄 함량에 따라 크게 나타났다. 5. 종이 필터지에서 시트의 평량이 bulk에 가장 큰 인자로 작용하였는데 이는 같은 두께에서 평량올 변화시킨 요인으로 판단되며 시트의 평량이 높을수록 감소하였고 활성탄 함량, Sw-BKP의 배합비 가 높을수록 증가하였다. 또한, 인자간의 교호작용은 평 량과 활성 탄 함량에 따라 크게 작용하였다. 6 6. Crimp index는 관능검사 결과로서 활성탄 함량이 증가함에 따라 현저하게 저하되었으며 평량 및 S Sw-BKP의 배합비가 높을수록 양호한 결과를 나타내었다. 인자간의 교호작용에서는 평량과 펄프 배합비에 따라 가장 높은 경향을 나타내었다. 7 활성탄을 첨가하여 제조한 종이필터의 담배 연기성분 흡착능은 acetate tow에 charcoal을 첨가한 필터에 비하여 tar흡착능이 6% 이상 향상되었고, 특히 증기상 물질(vapour phase)중 aldehyde류에 대한 제거율(removal efficiency)이 높게 나타났다. 8. 건식 크림핑 방법에 의한 담배필터 제조시 펼프의 홉착능, 시트의 강도적 특성, 크림핑 조건 및 담 배 연기성분 흡착능 등을 고려하여 적정조건을 선정하였으며, 펄프 배합비(Sw-BKP따w-BKP)는 6 65/35, 시트의 평량은 40g/$m^2$ 활성탄 함량은 10% 이었다.

• Nuclear Engineering and Technology
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• v.56 no.3
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• pp.803-811
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• 2024

Nuclear accidents such as Fukushima Daiichi have highlighted the potential of passive safety systems to replace or complement active safety systems as part of the overall prevention and/or mitigation strategies. In addition, passive systems are key features of Small Modular Reactors (SMRs), for which they are becoming almost unavoidable and are part of the basic design of many reactors available in today's nuclear market. Nevertheless, their potential to significantly increase the safety of nuclear power plants still needs to be strengthened, in particular the ability of computer codes to determine their performance and reliability in industrial applications and support the safety demonstration. The PASTELS project (September 2020-February 2024), funded by the European Commission "Euratom H2020" programme, is devoted to the study of passive systems relying on natural circulation. The project focuses on two types, namely the SAfety COndenser (SACO) for the evacuation of the core residual power and the Containment Wall Condenser (CWC) for the reduction of heat and pressure in the containment vessel in case of accident. A specific design for each of these systems is being investigated in the project. Firstly, a straight vertical pool type of SACO has been implemented on the Framatome's PKL loop at Erlangen. It represents a tube bundle type heat exchanger that transfers heat from the secondary circuit to the water pool in which it is immersed by condensing the vapour generated in the steam generator. Secondly, the project relies on the CWC installed on the PASI test loop at LUT University in Finland. This facility reproduces the thermal-hydraulic behaviour of a Passive Containment Cooling System (PCCS) mainly composed of a CWC, a heat exchanger in the containment vessel connected to a water tank at atmospheric pressure outside the vessel which represents the ultimate heat sink. Several activities are carried out within the framework of the project. Different tests are conducted on these integral test facilities to produce new and relevant experimental data allowing to better characterize the physical behaviours and the performances of these systems for various thermo-hydraulic conditions. These test programmes are simulated by different codes acting at different scales, mainly system and CFD codes. New "system/CFD" coupling approaches are also considered to evaluate their potential to benefit both from the accuracy of CFD in regions where local 3D effects are dominant and system codes whose computational speed, robustness and general level of physical validation are particularly appreciated in industrial studies. In parallel, the project includes the study of single and two-phase natural circulation loops through a bibliographical study and the simulations of the PERSEO and HERO-2 experimental facilities. After a synthetic presentation of the project and its objectives, this article provides the reader with findings related to the physical analysis of the test results obtained on the PKL and PASI installations as well an overall evaluation of the capability of the different numerical tools to simulate passive systems.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.88-89
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• 2013

A variety of influenza A viruses from animal hosts are continuously prevalent throughout the world which cause human epidemics resulting millions of human infections and enormous industrial and economic damages. Thus, early diagnosis of such pathogen is of paramount importance for biomedical examination and public healthcare screening. To approach this issue, here we propose a fully integrated Rotary genetic analysis system, called Rotary Genetic Analyzer, for on-site detection of influenza A viruses with high speed. The Rotary Genetic Analyzer is made up of four parts including a disposable microchip, a servo motor for precise and high rate spinning of the chip, thermal blocks for temperature control, and a miniaturized optical fluorescence detector as shown Fig. 1. A thermal block made from duralumin is integrated with a film heater at the bottom and a resistance temperature detector (RTD) in the middle. For the efficient performance of RT-PCR, three thermal blocks are placed on the Rotary stage and the temperature of each block is corresponded to the thermal cycling, namely $95^{\circ}C$ (denature), $58^{\circ}C$ (annealing), and $72^{\circ}C$ (extension). Rotary RT-PCR was performed to amplify the target gene which was monitored by an optical fluorescent detector above the extension block. A disposable microdevice (10 cm diameter) consists of a solid-phase extraction based sample pretreatment unit, bead chamber, and 4 ${\mu}L$ of the PCR chamber as shown Fig. 2. The microchip is fabricated using a patterned polycarbonate (PC) sheet with 1 mm thickness and a PC film with 130 ${\mu}m$ thickness, which layers are thermally bonded at $138^{\circ}C$ using acetone vapour. Silicatreated microglass beads with 150~212 ${\mu}L$ diameter are introduced into the sample pretreatment chambers and held in place by weir structure for construction of solid-phase extraction system. Fig. 3 shows strobed images of sequential loading of three samples. Three samples were loaded into the reservoir simultaneously (Fig. 3A), then the influenza A H3N2 viral RNA sample was loaded at 5000 RPM for 10 sec (Fig. 3B). Washing buffer was followed at 5000 RPM for 5 min (Fig. 3C), and angular frequency was decreased to 100 RPM for siphon priming of PCR cocktail to the channel as shown in Figure 3D. Finally the PCR cocktail was loaded to the bead chamber at 2000 RPM for 10 sec, and then RPM was increased up to 5000 RPM for 1 min to obtain the as much as PCR cocktail containing the RNA template (Fig. 3E). In this system, the wastes from RNA samples and washing buffer were transported to the waste chamber, which is fully filled to the chamber with precise optimization. Then, the PCR cocktail was able to transport to the PCR chamber. Fig. 3F shows the final image of the sample pretreatment. PCR cocktail containing RNA template is successfully isolated from waste. To detect the influenza A H3N2 virus, the purified RNA with PCR cocktail in the PCR chamber was amplified by using performed the RNA capture on the proposed microdevice. The fluorescence images were described in Figure 4A at the 0, 40 cycles. The fluorescence signal (40 cycle) was drastically increased confirming the influenza A H3N2 virus. The real-time profiles were successfully obtained using the optical fluorescence detector as shown in Figure 4B. The Rotary PCR and off-chip PCR were compared with same amount of influenza A H3N2 virus. The Ct value of Rotary PCR was smaller than the off-chip PCR without contamination. The whole process of the sample pretreatment and RT-PCR could be accomplished in 30 min on the fully integrated Rotary Genetic Analyzer system. We have demonstrated a fully integrated and portable Rotary Genetic Analyzer for detection of the gene expression of influenza A virus, which has 'Sample-in-answer-out' capability including sample pretreatment, rotary amplification, and optical detection. Target gene amplification was real-time monitored using the integrated Rotary Genetic Analyzer system.