• Nuclear Engineering and Technology
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• 제47권7호
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• pp.924-933
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• 2015

The correlation of the isotopic composition of uranium, plutonium, neodymium, and cesium with the burnup for high burnup pressurized water reactor fuels irradiated in nuclear power reactors has been experimentally investigated. The total burnup was determined by Nd-148 and the fractional $^{235}U$ burnup was determined by U and Pu mass spectrometric methods. The isotopic compositions of U, Pu, Nd, and Cs after their separation from the irradiated fuel samples were measured using thermal ionization mass spectrometry. The contents of these elements in the irradiated fuel were determined through an isotope dilution mass spectrometric method using $^{233}U$, $^{242}Pu$, $^{150}Nd$, and $^{133}Cs$ as spikes. The activity ratios of Cs isotopes in the fuel samples were determined using gamma-ray spectrometry. The content of each element and its isotopic compositions in the irradiated fuel were expressed by their correlation with the total and fractional burnup, burnup parameters, and the isotopic compositions of different elements. The results obtained from the experimental methods were compared with those calculated using the ORIGEN-S code.

• 생약학회지
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• 제50권3호
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• pp.198-204
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• 2019

A facile and convenient method was developed for the mass production of epigallocatechin gallate (EGCG) rich green tea extract (Er-GTE). The Er-GTE was successfully obtained from the crude water extract of green tea by the combination of two step purification, i.e., a simple adsorption process on the cation exchange resins (Trilite SCR-B) followed by the chromatography with Diaion HP-20 resins. The green tea extract produced by water extraction under $45^{\circ}C$ was subjected to adsorb on the strongly acidic cation exchange resin, Trilite SCR-B. The eluate passed through the resin was reabsorbed on Diaion HP-20 resin, which was subjected to elute with a mixture of water and alcohol by conventional chromatographical manner. The EGCG content in Er-GTE was estimated above 97% by HP-LC analysis and the newly developed method was regarded as the most suitable and appropriate process for the mass production of epigallocatechin gallate rich green tea extract (Er-GTE).

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 1997년도 학술발표회 논문집
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• pp.441-446
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• 1997

• Advances in aircraft and spacecraft science
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• 제5권4호
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• pp.499-513
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• 2018

One of the major problems in glass fiber reinforced epoxy (GFRE) composite pipes is the durability under water absorption. This condition is generally recognized to cause degradations in strength and mechanical properties. Therefore, there is a need for an intelligent system for detecting the absorption rate and computing the mass of water absorption (M%) as a function of absorption time (t). The present work represents a new non-destructive evaluation (NDE) technique for detecting the water absorption rate by evaluating the dielectric properties of glass fiber and epoxy resin composite pipes subjected to internal hydrostatic pressure at room temperature. The variation in the dielectric signatures is employed to design an electrical capacitance sensor (ECS) with high sensitivity to detect such defects. ECS consists of twelve electrodes mounted on the outer surface of the pipe. Radius-electrode ratio is defined as the ratio of inner and outer radius of pipe. A finite element (FE) simulation model is developed to measure the capacitance values and node potential distribution of ECS electrodes on the basis of water absorption rate in the pipe material as a function of absorption time. The arrangements for positioning12-electrode sensor parameters such as capacitance, capacitance change and change rate of capacitance are analyzed by ANSYS and MATLAB to plot the mass of water absorption curve against absorption time (t). An analytical model based on a Fickian diffusion model is conducted to predict the saturation level of water absorption ($M_S$) from the obtained mass of water absorption curve. The FE results are in excellent agreement with the analytical results and experimental results available in the literature, thus, validating the accuracy and reliability of the proposed expert system.

• 해양환경안전학회지
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• 제22권7호
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• pp.836-845
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• 2016

본 연구에서는 하계 한국 남동해 간절곶 주변해역의 냉수대 구조와 변동을 CTD 관측과 수층별 수온 장기 연속 모니터링 자료를 이용하여 분석하였다. 냉수대의 표층수온은 냉수기 이전과 $-12^{\circ}C$의 차이를 보였으며 해저지형 효과로 간절곶에서 냉수대 세력이 가장 컸다. 남북해역 간 등온선의 시계열분포에 간절곶을 경계로 공간변화가 발생해 간절곶 주변 해저지형이 언덕(hill)역할을 하고 있음이 추정되었다. 냉수대는 해안에 평행한 풍속이 양(+)의 값일 때 출현하는 연안용승반응을 나타냈고, 수온의 감소와 상승은 풍향이 바뀐 후 하루 이내에 반응하였다. 간절곶 주변은 얕은 수심 주위에서 발생하는 와류효과가 결합하여 바람에 의한 용승효과가 강화되었다. 수온변화는 2~6일 주기의 바람변동에 민감하였으며, 수온감소는 12~36시간의 위상차를 나타냈다. 냉수대가 출현한 7월은 2~3일 주기, 8월은 3~8일 주기에서 바람-수온변화의 상관성이 컸다.

• 한국물환경학회지
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• 제20권3호
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• pp.223-230
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• 2004

The QUAL2E and Box-Jenkins time series model were applied to the Miho river, a main tributary of the Geum river, to predict water quality. The models are widely used to predict water quality in rivers and watersheds because of its accuracy. As results of the study, we concluded as follows: Pollutant loadings in upper stream of Miho river were determined to 57,811 kgBOD/d, 19,350 kgTN/d, and 5,013 kgTP/d. The loading of TN in Mushim river was 19,450 kgTN/d, respectively. As the mass loadings were compared with pollutant sources, it concluded that the farming livestock contributed highly to mass emissions of BOD and TP and the population contributed to TN mass loading. The observed water quality values were applied to the models to verify and the models were used to predict the water quality. The QUAL2E Model predicted the concentrations of DO, BOD, TN and TP with high accuracy, but not for E-Coli. The Box-Jenkins time series model also showed high prediction for DO, BOD and TN. However, the concentrations of TP and E-Coli were poorly predicted. The result shows that the QUAL2E model is more applicable in Miho basin for prediction of water quality compared to Box-Jenkins time series model.

• 한방재활의학과학회지
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• 제20권1호
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• pp.167-182
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• 2010

Objectives : The purpose of this study is to find correlation about 7-Zone-Diagnostic System and Clinical Parameters using Oriental Health Examination. Methods : Subjects of our study were 325 cases who took Oriental Health Examination. We collected the data of body composition analysis, 7-Zone-Diagnostic System, blood analysis and devided by 7-Zone-Diagnostic system to acceleration, normalcy and depression. Results and Conclusions : The values of muscle mass, body fat mass, abdomen obesity rate, right arm water index, left arm water index, trunk water index, right leg water index, left leg water index, BMI, BMR, GOT, GPT, ${\gamma}$-GTP, BUN, TC, triglyceride and hemoglobin were continuous with 7-Zone-Diagnostic system.

• Journal of Advanced Marine Engineering and Technology
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• 제20권5호
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• pp.68-75
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• 1996

The vacuum drying characteristics of water-saturated porous media were studied experimentally. The water-saturated porous media, water-saturated sand layer, was heated by the isothermal bottom wall of the rectangular vessel. The vacuum drying rate and temperature distribution of the sand layer were measured and calculated under a variety of conditions of heated wall temperature, vacuum rate, and thickness of the test material. It was found that the drying rate due to the heat and mass teansfer is greatly influenced by the heated wall temperature, vacuum rate, and thickness of the test material.

• 설비공학논문집
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• 제13권5호
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• pp.422-430
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• 2001

In the present study, an evaporative generation process of ammonia-water solution film on the vertical plate was analysed. For the utilization of waste heat, hot water of low temperature was used as the heat source. The continuity, momentum, energy and diffusion equations for the solution film and vapor mixture were formulated in integral forms and solved numerically. Counter-current solution-vapor flow resulted in the refrigerant vapor of the higher ammonia concentration than that of co-current flow. Eve the rectification of refrigerant vapor was observed near the inlet of solution film in counter-current flow. For the optimum operation of generator using hot water, numerical experiments, based on the heat exchange and generation efficiencies. revealed the inter-relationships among the Reynolds number of the solution film and hot water, and the length of generator. Enhancement of heat and mass transport in the solution film was found to be very effective for the improvement of generation performance, especially at high solution flow rate.

• 한국환경보건학회지
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• 제31권5호
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• pp.387-397
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• 2005

In oder to understand the deposition possibility of water-soluble inorganic ions in the atmospheric fine particulates for the human respiratory tract, the mass size distribution of ion species was measured using an Anderson sampler in the Iksan during fall, 2004. Samples were analyzed for major water-soluble ions using Dionex DX-100 ion chromatograph. The size distribution of water-soluble inorganic ions in the atmospheric particulates appeared bimodal distribution, which were divided around $1-2{\mu}m$ into two groups. Mass site distribution of total ion in the coarse mode was found to be almost similar level during the sampling period, but fluctuations of mass size distribution in the fine mode were observed. Considering the mass size distribution of total ion concentrations for the respiratory deposition region, it was found that about 77.1% of total tons could be deposited in the alveolar region, and which dominated the daily variation of total ion concentrations. The concentration of total ions, which could be deposited in both the head region and the tracheobronchial region, was $3.95{\mu}g/m^3$, whereas that in the alveolar rerion was $13.28{\mu}g/m^3$. Dominant ions which could be deposited in the alveolar region were ${NO_3}{^-},\;{SO_4}^{2-}\;and\;{NH_4{^+}$, accounting for about 40%, 27% and 22% of the total ions, respectively. Although $K^+$ was approximately 3% of total ions, it was shown that most of this could be deposited in the alveolar region due to its high fraction of small size distribution originated from anthropogenic source of biomass burning. The presence of these ions in the fine mode may be of public health significance as they are very biologically harmful to health and have a high probability of being deposited in human lung tissue.