• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
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• pp.1998-2000
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• 2005

The effects of the addition of nanocrystalline Y2O3 powder on the microstructure and superconducting properties have been investigated in YBCO films prepared by TFA-MOD process. Precursor solution doped with extra $Y_2O_3$ Powder was prepared by adding $Y_2O_3$ powder into a stoichiometic precursor solution with a cation ratio of Y:Ba:Cu=1:2:3. Coating solutions with and without $Y_2O_3$ doping were coated on $LaAlO_3(100)$ single crystal by a dip coating method, cacination and conversion heat treatments were performed at the controlled atmosphere containing water vapor Current carry capacity(Jc) of YBCO film was enhanced about 50% by $Y_2O_3$ doping. It is thought that the enhancement of Jc is due to the better connectivity of YBCO grains and/or the flux pinning by the presence of nanocrystalline $Y_2O_3$ Particles embedded in YBCO grains.

• Food Science and Biotechnology
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• 제15권4호
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• pp.564-571
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• 2006

In order to improve the quality and preservation of nabakkimchi, omija was added as an ingredient to determine its effect on the physicochemical characteristics of kimchi during fermentation, as well as the optimum level of omija extract. Omija extract was prepared from omija seeds by extraction with water for 9 hr at room temperature in concentrations (w/v) of 0.5, 1.0, 1.5, and 2.0% for use as an ingredient in nabakkimchi. The physicochemical characteristics of nabakkimchi containing omija extract were analyzed during fermentation of the product for up to 25 days. Delayed fermentation was observed, particularly in the early stage of fermentation, and was dependent on the concentration of the omija extract, as shown by stabilization of pH decreases and increases in the total acidity. An increased concentration of omija extract also raised the initial total vitamin C content and the reducing sugar content, which both then stabilized thereafter. Delayed development of turbidity within the optimum fermentation period of 16 days, increased redness and total color difference, and an electron-donor effect were also promoted by the omija extract. However, the omija extract also triggered extra tannin production, which leads to an astringent taste, especially at the 1.5 and 2.0% treatment levels.

• Structural Engineering and Mechanics
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• 제51권4호
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• pp.663-683
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• 2014

In order to study the dynamic failure mechanism and aseismic measure for high concrete gravity dam under earthquake, the comparative models experiment on the shaking table was conducted to investigate the dynamic damage response of concrete gravity dam with and without the presence of reinforcement and evaluate the effectiveness of the strengthening measure. A new model concrete was proposed and applied for maintaining similitude with the prototype. A kind of extra fine wires as a substitute for rebar was embedded in four-points bending specimens of the model concrete to make of reinforced model concrete. The simulation of reinforcement concrete of the weak zones of high dam by the reinforced model concrete meets the similitude requirements. A tank filled with water is mounted at the upstream of the dam models to simulate the reservoir. The Peak Ground Acceleration (PGA) that induces the first tensile crack at the head of dam is applied as the basic index for estimating the overload capacity of high concrete dams. For the two model dams with and without strengthening tested, vulnerable parts of them are the necks near the crests. The results also indicate that the reinforcement is beneficial for improving the seismic-resistant capacity of the gravity dam.

• Nuclear Engineering and Technology
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• 제40권1호
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• pp.93-98
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• 2008

Several adhesive tapes have been studied in terms of their suitability for securing gold wires into positions for neutron flux measurements in the reactor core and irradiation facilities surrounding the core of the Open Pool Australian Light water (OPAL) reactor. Gamma ray spectrometry has been performed on each irradiated tape in order to identify and quantify activated components. Numerous metallic impurities have been identified in all tapes. Calculations relating to both the effective neutron shielding properties of the tapes and the error in measurement of the $^{198}Au$ activity caused by superfluous activity due to residual tape have been made. The most important identified effects were the prolonged cooling times required before safe enough levels of radioactivity to allow handling were reached, and extra activity caused by residual tape when measured with an ionisation chamber. Knowledge of the most suitable tape can allow a minimal contribution due to these effects, and the use of gamma spectrometry in preference to ionisation chamber measurements of the flux wires is shown to make all systematic errors due to the tape completely negligible.

• Asian-Australasian Journal of Animal Sciences
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• 제8권3호
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• pp.275-280
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• 1995

The effect of supplemented high protein diet intake on renal urea regulation in swamp buffalo was carried out in the present experiment Five swamp buffalo heifers weighing between 208-284 kg were used for this study. The animals were fed with a supplementary high protein diet and renal function and kinetic parameters for urea excretion were measured. This was compared to a control period where the same animals had been fed only with paragrass and water hyacinth. For 2 months the same animals were fed a mixed of paragrass, water hyacinth plus 2 kgs of a high protein supplement (protein 18.2% DM basis) per head per day. In comparison to the control period, there were no differences in the rate of urine flow, glomerular filtration rate (GFR), effective renal plasma flow (ERPF), plasma urea concentration and filtered urea. In animals supplemented with high protein intake mean values of urea clearance, excretion rate and the urea urine/plasma concentration ratio markedly increased (p < 0.05) while renal urea reabsorption significantly decreased from 40% to 26% of the quantity filtered. In this same study group urea space distribution and urea pool size increased which coincided with an increase in plasma volume (p < 0.05). Plasma protein decreased while plasma osmolarity increased (p < 0.05). Both urea turnover rate and biological half-life of $^{14}C$-urea were not affected by a supplementary high protein intake. The results suggest that animals supplemented with high protein diets are in a state of dynamic equilibrium of urea which is well balanced between urea excreted into the urine and the amount synthesized. The limitation for renal tubular urea reabsorption would be a change in extra-renal factors with an elevation of the total pool size of nitrogenous substance.

• 대한기계학회논문집 C: 기술과 교육
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• 제2권1호
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• pp.65-72
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• 2014

본 연구에서는 지역난방 공사에서 사용하고 있는 성층 축열조의 불가용 에너지를 줄이기 위해 단열층을 설계하였다. 단열층은 추가적인 장치 없이 고온수와 저온수의 밀도차이로 생기는 부력으로 운용된다. 축열조의 내부 온도분포를 모사할 수 있는 해석모델을 Matlab Simulink 를 이용하여 제작하고 해석 결과를 이용하여 단열층의 소재와 두께를 결정하였다. 또한 축열조의 축소실험을 통하여 단열층의 운용 가능성을 확인하였다. 실험 결과, 단열층이 축열 방열과정에서 고온수와 저온수의 혼합과 열전도로 인한 온도 경계층형성을 효과적으로 억제할 수 있다는 것을 확인하였다. 단열층을 설치한 축소실험에서는 단열층이 없는 축열조보다 약 1540 J 의 추가 가용에너지가 보존되었고 이를 실제 축열조에 적용할 경우 약 6%의 축열효율이 증가될 것으로 예상된다.

• Bulletin of the Korean Chemical Society
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• 제25권5호
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• pp.681-686
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• 2004

Ti-ZSM-5 prepared by secondary synthesis, from the reaction of H-ZSM-5 with vapor phase $TiCl_4$, was characterized with several physicochemical techniques including FT-IR and UV/VIS-DRS. It was found that zeolite structure, surface area and pore volume did not change, and the framework aluminum could not be replaced by titanium atom during the secondary synthesis of Ti-ZSM-5. The incorporation of titanium into the framework might be due to reaction of $TiCl_4$with the silanol groups associated with defects or surface sites. The formation of extra-framework titanium could not be avoided, unless the samples were further treated by water vapor at 550 $^{\circ}C$ or higher temperature. High temperature steam treatment of Ti-ZSM-5 prepared by chemical vapor deposition with $TiCl_4$was efficient to prevent the formation of non-framework titanium species. Ti-ZSM-5 zeolites prepared in this work contained only framework titanium species and exhibited improved catalytic property close to TS-1 prepared by hydrothermal synthesis.

• 한국지반환경공학회 논문집
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• 제12권4호
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• pp.33-41
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• 2011

연약지반상에 설치되는 항만구조물의 경우 편재하중에 의해 지반내의 과잉간극수압이 증가하게 되고, 토립자의 소성화로 인한 측방변형이 발생된다. 본 연구는 부산 ${\bigcirc}{\bigcirc}{\bigcirc}$현장에 설치되는 케이슨의 측방변위 및 침하 계측 데이터와 유한요소 해석 프로그램인 Plaxis를 이용한 수치해석 결과를 비교 분석하였다. 수치해석 시 실제 현장의 지반 물성치와 시공단계 및 기간 설정은 지반 조사 보고서 및 실시설계 보고서를 참고하여 적용하였으며, 현장 계측 단면 1개소 단면을 선정하여 수치해석하였다. 측방변위는 S.C.P.로 지반개량된 구간에 거치된 케이슨 전면부에 설치되어 있는 지중 경사계의 위치를 지점으로 측정하였고, 침하는 케이슨 배후의 여성토부의 중심에 설치되어 있는 지표 침하판의 위치를 지점으로 선정하여 현장계측하였다. 수치해석 결과 측방 변위의 해석 값은 실측치보다 크게 나타났으며, 실측값은 지속적인 완만한 증가양상을 보였지만 해석값은 단계 성토 때마다 큰 변위를 나타내는 계단식 증가를 보였다. 반면에 침하량 변화 양상은 측방변위 양상과 비슷한 거동을 보였고 변화량은 비슷하게 나타났다.

• 대한가정학회지
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• 제43권1호
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• pp.145-165
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• 2005

In 1937, most Korean compatriot who lived in Yunhaeju moved to Kazakhstan and Uzbekistan in Central Asia following the deportation policy of Russia. Korean compatriot have kept their traditional life style for 140 years, without a deep relationship with Korea. This study examined the heating systems of Korean compatriot in Yunhaeju, Kazakhstan and Uzbekistan, Russia. A literature review and field research, based on Ethnography as a research method, was employed. The results of the research were as following: 1) Korean compatriot in Yunhaeju use a Pechika, which is a radiator that uses hot water, and a Gudul as the main heating systems, but the use of a Pechika was most common. A Pechika functions for cooking as well as for warming the house. The room with the Gudul was connected to the kitchen, so this space was used as a place for cooking and eating, for family members to meet. Many kinds of fuel, like gas and electricity, were used to power the heating systems. 2) Korean compatriot in Kazakhstan use radiators, with hot water as the main heating system, with ratio using Gudul used in this region being the highest of all the three areas. The most common fuels used for a Gudul were wood and coal, and gas was also used in cooking. The room with the Gudul was planned to be located beside the fireplace, without any walls. The people using a Gudul use that place for eating and meeting, as well as for family members to sleep. 3) The main heating system of Korean compatriot in Uzbekistan was a radiator using hot water, and those with pipes containing hot water buried under the floor were very common. The function is very similar to that of a Gudul, so most people using this type of radiator would sleep on the floor. Those people with a traditional Gudul not using them were mostly in Uzbekistan. The reason for this was that the family members had diminished, so it was hard work for elderly parents to manage an extra building containing a Gudul. Gas was the fuel generally used for heating and cooking in Uzbekistan. 4) Guduls were used in the Korean compatriot's houses in all three areas, even though they have changed in structure to adapt to the Russian life style. However, Guduls have still been functioning to maintain a traditional life style in Korean compatriot's houses for the gathering of family members.

• 핵의학기술
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• 제12권1호
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• pp.49-56
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• 2008

Purpose: Whole body imaging with radioiodine can detect functioning metastases. Non-physiologic I-131 uptake detected on images usually is interpreted as suggesting functioning thyroid metastases. However, extra-thyroidal I-131 accumulation does not always imply thyroid cancer metastases and has been reported in many circumstances. In order to avoid unnecessary therapeutic interventions it is important to distinguish false-positive sites of I-131 localization. We study here to remove false-positive sites around esophagus region on I-131 whole body imaging in patients who were administrated thyroidectomy. Materials and Methods: From April to August in 2007, we had the patients who had visited our department after they received thyroidectomy due to thyroid cancer. They were given I-131, and performed radioiodine body scan after 41 to 50 hours. Patients were whole-body-scanned for the speed of 8 cm per minute. After that, we took anterior and posterior static images around the patients' neck measured by 300 thousand counts per image. We selected 44 patients who had hot spots around neck region, we divided the patients into two groups. One group was given 0.5 L of water and the other group was given 0.5 L of water with 1 g of Vitamin C dissolved. The patients were asked to drink the fluid for one minute in sitting position and after that, we measured 300 kilo counts per image again. We compared prior anterior, posterior static images with anterior, posterior images after the patients had water or water that Vitamin C resolved. Results: In using water, both observer 1 and 2 interpreted 6 patients were washed out. In the water with Vitamin C resolved, observer 1 and 2 interpreted 9 and 8 patients were washed out. Observer 1 and 2 interpreted 6 and 5 patients had 'indeterminate' when they used water. Both observer 1 and 2 interpreted 6 patients had 'indeterminate' when they used water with Vitamin C resolved. When they used water, observer 1 interpreted 10 patients had 'unchanged' and observer 2 interpreted 11 patients had 'unchanged'. Differently, when they used water with vitamin C resolved, observer1 had 8 patients having 'unchanged'and observer 2 had 9. Conclusion: As a result, by making patients drink 0.5 liter of water which has vitamin C resolved helped getting rid of false-positive sites in esophagus. Therefore, based on this study, we believe that drinking water with vitamin C dissolved is very in terms of reducing false-positive hot spot around the esophagus for the iodine-131 whole body scan.