• Proceedings of the Korean Vacuum Society Conference
• /
• 2012.02a
• /
• pp.321-322
• /
• 2012

의료용 방사선 장비는 초기의 아날로그 방식의 필름 및 카세트에서 진보되어 현재는 디지털 방식의 DR (Digital Radiography)이 널리 사용되며 그에 관한 연구개발이 활발히 진행되고 있다. DR은 크게 간접방식과 직접방식의 두 분류로 나눌 수 있는데, 간접방식은 X선을 흡수하면 가시광선으로 전환하는 형광체(Scintillator)를 사용하여 X선을 가시광선으로 전환하고, 이를 Photodiode와 같은 광소자로 전기적 신호로 변환하여 방사선을 검출하는 방식을 말하며, 직접 방식은 X선을 흡수하면 전기적 신호를 발생 시키는 광도전체(Photoconductor)를 사용하여 광도전체 양단 전극에 고전압을 인가한 형태를 취하고 있는 가운데, X선이 조사되면 일차적으로 광도전체 내부에서 전자-전공쌍(Electron-hole pair)이 생성된다. 이들은 광도전체 양단의 인가되어 있는 전기장에 의해 전자는 +극으로, 전공은 -극으로 이동하여 아래에 위치한 Active matrix array을 통해 방사선을 검출하는 방식이다. 본 연구에서는 직접방식 X-ray 검출기에서 활용되는 a-Se을 ITO (Indium Thin oxide) glass 상단에 Thermal evaporation증착을 이용하여 두께 $50{\mu}m$, 33 넓이로 증착 시킨 다음, a-Se상단에 Sputtering증착을 이용하여 ITO를 11 cm, 22 cm, $2.7{\times}2.7cm$ 넓이로 증착시켜 상하부의 ITO를 Electrode로 이용하여 직접방식의 X-ray검출기 샘플을 제작하였다. 제작 과정 중 a-Se의 Thermal evaporation증착 시, 저진공 $310^{-3}_{Torr}$, 고진공 $2.210^{-5}_{Torr}$에서 보트의 가열 온도를 두 번의 스텝으로 나누어 증착 시켰다. 첫 번째 스텝 $250^{\circ}C$, 두 번째 스텝은 $260^{\circ}C$의 조건으로 증착하여 보트 내의 a-Se을 남기지 않고 전량을 소모할 수 있었으며, 스텝간의 온도차를 $10^{\circ}C$로 제어하여 균일한 박막을 형성 할 수 있었다. Sputtering증착 시, 저진공 $2.510^{-3}$, 고진공 $310^{-5}$에서 Ar, $O_2$를 사용하여 100 Sec간 플라즈마를 생성시켜 ITO를 증착하였다. 제작된 방사선 각각의 검출기 샘플 양단의 ITO에 500V의 전압을 인가하고, 진단 방사선 범위의 70 kVp, 100 mA, 0.03 sec 조건으로 X-ray를 조사시켜 ITO넓이에 따른 민감도(Sensitivity)와 암전류(Dark current)를 측정하였다. 측정결과 민감도(Sensitivity)는 X-ray샘플의 두께에 따른 $1V/{\mu}m$ 기준 시, 증착된 ITO의 넓이가 11 cm부터 22 cm, $2.7{\times}2.7cm$까지 각각 $7.610nC/cm^2$, $8.169nC/cm^2$, $6.769nC/cm^2$로 22 cm 넓이의 샘플이 가장 높은 민감도를 나타내었으나, 암전류(Dark current)는 $1.68nA/cm^2$, $3.132nA/cm^2$, $5.117nA/cm^2$로 11 cm 넓이의 샘플이 가장 낮은 값을 나타내었다. 이러한 데이터를 SNR (Signal to Noise Ratio)로 합산 하였을 시 104.359 ($1{\times}1$), 60.376($2{\times}2$), 30.621 ($2.7{\times}2.7$)로 11 cm 샘플이 신호 대 별 가장 우수한 효율을 나타냄을 알 수 있었다. 따라서 ITO박막의 면적이 클수록 민감도는 우수하나 그에 따른 암전류의 증가로 효율이 떨어짐을 검증 할 수 있었으며, 이는 ITO면적이 넓어짐에 따른 저항의 증가로 암전류에 영향을 끼침을 할 수 있었다. 본 연구를 통해 a-Se의 ITO 박막 면적에 따른 전기적 특성을 검증할 수 있었다.

• Applied Biological Chemistry
• /
• v.14 no.1
• /
• pp.9-18
• /
• 1971

In order to obtain basic information on the production of single cell protein from petroleum, more than 400 yeast strains were isolated from various soil samples in Korea utilizing petroleum hydrocarbon as the sole carbon source. A yeast strain showing the highest cell yield among the isolated strains was selected and identified. The optimal culture condition was searched in the flasks shaken throughout the procedure. And the growing characteristics for the selected yeast strain and chemical analysis of the yeast cell component were carried out. The results obtained were as follows: 1. The selected yeast strain was identified as Candida curvata and we named it Candida curvata-SNU 70. 2. The composition of the medium proposed for the present yeast strain is: Light Gas Oil 30ml, Urea 400mg, Ammonium sulfate 100mg, Potasium phosphate (monobasic) 670mg, Sodium phosphate (dibasic) 330mg, Magnesium sulfate 500mg, Calcium carbonate 3g, Yeast extract 50mg, Tween 20 0.05ml, Tap water 1,000ml. 3. Other culture conditions employed for the yeast were pH 5.5-7.0, temp. $30^{\circ}C$ under an affluent aerobic state. 4. Addition of light gas oil in portions to the culture media as the growth proceeded was more effective, especially in the cultivation on the higher oil concentration media. 5. Studies on the propagation of the yeast cells in the light gas oil medium revealed that the yeast has the lag phase lasted 16 hours and the logarithmic growth phase covered 16 to 28 hours. The specific growth rate was about $0.22\;hr^{-1}$ and doubling time was 3.2 hrs. during the logarithmic growth phase. 6. Under the cultural condition employed, the cell yield against the amount of light gas oil (wt%) was 16.1% and the protein content of the dried yeast cells was 48.4%.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.15 no.3
• /
• pp.198-206
• /
• 1995

Baled silage making(BS) of selected forage crops was discussed during 1991-1993, to determine the best cutting time of the plants for BS production, BS yields and silage quality. Seven species of forage crops and pasture grasses(rye, barley, spring oat, Italian ryegrass, orchardgrass, alfalfa and grass-legume pasture mixtures) were harvested at different stage of growth from young plant to physiological maturity, and baled in a self constructed square baling chamber. Each bales, measured 90cm length, 60cm width and 50cm height, were wrapped with 0.05mrn thick polyethylene plastic film, and stored in stack silo. Each bales were weighed between 15-20 kg in dry matter basis. The effects of pre wilting and formic acid addition on the silage quality of young plant materials, which contained high water concentration, was also evaluated during the experiment. Rye plant including of barley and spring oat were evaluated as a good materials for baled silage making. Fodder rye produced high quality BS with a value of silage quality point 84(Flieg's point) when the plant harvested at stage of greatest dry matter accumulation by 12.64 tonha. The best quality BS of barley was obtained at stage of hard dough to yellow stage by 11.9 ton/ha dry matter yield and 81 point silage quality. Italian ryegrass and pasture grasses including of orchardgrass, alfalfa and grass-legume pasture mixtures procuced also high quality bale silage by harvesting at stage of late blooming. However pre witting operation and formic acid addition was required for BS production of grass materials because of high water contents. Water contents of Italian ryegrass and other pasture species ranged 18.9%(Italian) to 20.8%(alfalfa). Silage quality point of Italian BS harvested at late blooing was increased from 72 to 88 by 1/2-one day pre wilting and 0.3% formic acid treatment. Silage quality of young plant materials of rye and other forage crops, barley and spring oat were also improved markedly through the pre wilting treatment and formic acid addition.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.37 no.4
• /
• pp.277-282
• /
• 2017

This study was conducted to evaluate on agronomic characteristics, forage quality and dry matter (DM) yields of mugwort (Artemisia princeps Pamp.) collected different region at Seongju in Kyeongbuk from 2014 to 2015. The experiment was arranged in randomized complete block design with three replications. Mugwort was planted on $17^{th}$ March, 2014 and harvested on $13^{th}$ September, 2014 and on $25^{th}$ May and $9^{th}$ September, 2015. DM yields of Dalsung(1), Seongju B.(1), Dalsung(2) and Sajuarissuk were 17.3, 16.8, 16.7 and $16.7(MT\;ha^{-1})$, respectively and the DM yields of those were higher (p<0.05) than the other mugworts in 2014. In 2015, DM yields of Dalsung(1), Dalsung(2), Seongju B.(1), and Sajuarissuk were 19.5, 19.3, 18.4 and $18.4(MT\;ha^{-1})$, respectively and DM yields of those were higher (p<0.05) than the others. DDM(digestable dry matter) content of mugworts was a range of 56.4 to 60.8% and that of Sajabalssuk, 60.8% was the highest. Seongju B.(1) 58.8% was higher than Seongju B.(2) 56.4% but there were no difference among the Dalsung(1) 58.4%, Dalsung(2) 58.1%, Sajuarissuk 57.7% and Yeongcheon. The result of this study indicated that Dalsung(1), Dalsung(2), Sajuarissuk and Seongju B.(1) would be recommendable for forage production.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.2 no.3
• /
• pp.10-17
• /
• 1999

In order to confirm the effectiveness of the natural river improvement technique, the analysis of vegetation was carried out in Yangjae stream between 1996 and 1998. The results of this study showed the numbers of riparian plants had increased from 41 species to 53 species, and the dominant species had changed from annual and biannual(Humulus japonicus, Persicaria thunbergii, Persicaria hydropiper, Panicum dichotomiflorum, Echinochloa crus-galli) to perennials (Phragmites communis). The variation in biomass and biodiversity index were measured and calculated according to the rehabilitation method. Biomass were varied 302 to $828g/m^2$ and biodiversity index was varied 1.53 to 1.52 at point bar plots(A treatment plots) from 1996 to 1998. In conclusion, the natural river improvement technique which has operated in Yanjaecheon for three years has contributed to restoration of riparian plants. Additionally, subsequent study using this technique should be followed in the near future.

• Journal of Hospice and Palliative Care
• /
• v.7 no.2
• /
• pp.221-231
• /
• 2004

Purpose: The purpose of this study was to analyze the need for child hospice care programs in families of children with cancer. Methods: The survey of 104 families who were taking care of children with cancer was conducted. This survey was conducted from February 2004 to July 2004 at two general hospitals in Seoul. The data were collected through a self-reporting questionnaire of 22 items. The items were classified into five areas by factor analysis to identify the construct validity. The reliability of the tool was established by Cronbach's alpha as .94 and the data collected were analyzed by descriptive statistics, t-test and ANOVA. Results: 1) The degree of need for hospice care of the subjects showed a high average of 3.40 (${\pm}3.8$). The need for 'emotional care of children' showed the highest mean (M=3.55), 'management of terminal physical symptoms'(M=3.49), 'control of secondary physical problems' (M=3.41), 'acceptance of the family's difficulty' (M=3.20), 'spiritual care for preparing for death'(M=3.17), respectively. 2) With respect to the demographic characteristics of the subjects, there were statistically significant differences in hospice care needs, according to the child's mother's age (F==4.980, P=.009), whether or not there were cancer patients among their siblings or relatives (t=2.423, P=.017). Conclusion: The family of children with cancer have a heavy burden of ambivalence, especially in relieving the anxiety and fear of their children, communicating about death, and managing physical symptoms. Child hospice care must be provided considering the needs of families of children with cancer. Thus popular needs as well as hospice nurses' higher concern and support for hospice care of children require further education and program development to meet the current demands.

• Journal of Life Science
• /
• v.20 no.1
• /
• pp.103-112
• /
• 2010

Pemetrexed has demonstrated clinical activity in non-small cell lung cancer (NSCLC) as well as other solid tumors. It transports into the cells via reduced folate carrier (RFC) and is polyglutamated by folypolyglutamate synthetase (FPGS). Pemetrexed directly inhibits several folate-dependent enzymes such as thymidylate synthase (TS), dihydrofolate reductase (DHFR), and glycinamide ribonucleotide formyltransferase (GARFT). We investigated the effects of genetic variations and the expression of RFC, FPGS, TS and DHFR enzymes on drug sensitivity to pemetrexed in NSCLC cells. Polymorphisms in RFC, FPGS, and DHFR were genotyped in four NSCLC cells - A549, PC14, HCC-1588, and H226. Real-time RT-PCR and Western blot was performed to evaluate mRNA transcripts and protein of these genes. The cytotoxicity of pemetrexed was measured by SRB assay. In PC14 and H226 cells, increased mRNA expressions of RFC and FPGS were associated with higher cytotoxicity to pemetrexed. 2R/2R genotype of TS and its increased mRNA expression were associated with drug resistance to pemetrexed in A549 cells, whereas 3R/3R genotype in TS with decreased mRNA expression was associated with higher sensitivity in H226 cells. After pemetrexed treatment, an inverse change of DHFR mRNA and protein expression was found. The strongest linkage disequilibrium (LD) was discovered between-1726C>T and -1188A>C SNP of DHFR gene. Our findings suggest the cytotoxic effect of pemetrexed may be associated with genetic polymorphisms and the expression level of genes involved in pemetrexed metabolisms in NSCLC cells.

• Journal of Life Science
• /
• v.24 no.7
• /
• pp.728-736
• /
• 2014

The purpose of this study was to improve and strengthen the function of eel extract prepared with 5 brix eel extract (EE), 5 brix eel and plant mix (black garlic, ginseng, black jujube) 0.35 ml extracts prepared and treated with the extract (EIM-1), and 0.7 ml (EIM-2) divided group. The extracts were administered to rats for five weeks during running training, and the lipid profiles and antioxidant enzyme activities were tested. The lipid content in liver and serum were lower than the normal group difference was not significant between groups. Serum total cholesterol was lower in the experimental group than the control group the mixed extract significantly lower level. HDL-cholesterol levels in the eel extract and eel mixed extract significantly increased by feeding the EIM-1 is 2.0 times, EIM-2 is increased by 2.3 times. Liver glycogen content in the experimental group performed the exercise group compared with the normal control group was significantly lower than in EIM is significantly higher than the control group. The TBARS content in the liver and serum was significantly higher than the normal group was lower than the control group. GOT and GPT were significantly decreased compared to the control group. Hepatic catalase activity was significantly increased in the EIM-1 group, and SOD and GSH-px activities were increased in the EIM-1 and EIM-2 groups. Supplementation with the eel and plant mix extract increased the activities of antioxidant enzymes. Thus, intake of the eel and plant mix extract could improve the antioxidant status and combat different types of oxidative stress.

• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• autumn
• /
• pp.305-310
• /
• 2001

The purpose of this study is to calculate delay damages for contractors. The study has been performed by investigation of delay cost occurrence status and the analysis of subway construction cases. The results of this study are as follows: 1. Delay cost( 1day) equivalent to $0.005\%$ of total construction cost by analysis case studies. 2. Including bank interest, dealy cost is analysed as the following; $1.1\~9.2\%$ of total construction cost in part extension period, $3.3\~11.0\%$ of total construction cost in total extension period. 3. In comparison between liquidated damages and delay cost, liquidated damages account for average 20.1 times of delay costs. 4. Acceleration cost will be calculate on the basis of delay cost calculation method. In the result of this method, acceleration cost is equal to delay cost at least or must be large than delay cost

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.43 no.7
• /
• pp.980-988
• /
• 2014

Seungmagalgeuntang (SG) is broadly used in traditional Oriental medicine especially in Korea, China, and Japan, for its many pharmacological effects. This study was carried out to investigate the antioxidative, antimicrobial, and anticytotoxic activities of SG and fermented seungmagalgeuntang (FSG). DPPH radical scavenging activities of SG and FSG were 70% and 74%, respectively, which increased slightly by fermentation. Nitrite scavenging activities were strongly altered at pH 1.2, (36.4% in SG and 38.3% in FSG) by addition of $200{\mu}g/g$. Superoxide dismutase-like activities were from 21.5% to 23.3% at a concentration of 0.4 mg/mL, and the highest value were observed in FSG. Total flavonoid contents of SG and FSG were 47.1 and $52.1{\mu}g/L$, respectively which shows an increase upon fermentation. In the antimicrobial activity test, $MIC_{50}$ values of SG and FSG were $800{\mu}g/mL$ for Candida albicans and 3,200 and $1,600{\mu}g/mL$ for Staphylococcus epidermidis and Staphylococcus aureus, respectively. Antibacterial effects were higher in FSG compared to SG. Anticytotoxic cadmium toxicities ranged from 63.5% to 76.1% at $10{\mu}g/mL$ of SG and FSG, and the highest value was observed in FSG. In the sensory evaluation, color, flavor, and overall preference values were higher in FSG.