• 암석학회지
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• 제14권4호
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• pp.237-250
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• 2005

ICP-MS로 화강암질 암석내 희토류원소의 함량 분석시 표준시료의 선택이 어느 정도 영향을 주는 지를 밝혀내기 위해, 상업용 표준시료(ACCU-standard, No. Cal-1), 화강암의 한국산 표준시료(KG-1), 미국산 표준시료(G-2), 일본산 표준시료(JC-1a, JC-2)를 각각 기준시료로 하여 각각의 희토류원소 함량을 측정하였다. 실험결과에 의하면, 경희토류(La-Gd) 분포도는 표준시료의 변화에 관계없이 대체적으로 추천값과 측정값 모두 일치하였다. 그러나 G-2 혹은 JG-2를 기준으로 측정했을 시, 다른 표준시료의 추천값과 측정값에 의한 중희토류(Gd-Lu)의 분포도는 많은 차이가 발생되었다. 이는 표준시료의 추천값의 오류 혹은 표준시료 암석의 지구화학적 특성에 기인된다. KG-1 혹은 JG-1a를 기준시료로 하여 희토류원소 함량을 측정했을 경우에는 G-2나 JG-2를 기준시료로 했을 때보다 추천값과 측정값에 의한 희토류원소의 분포도의 어긋남이 비교적 약한 편이다. 이는 국내 화강암류의 희토류원소 함량분석에 있어서의 표준시료로서 KG-1 혹은 JG-1a가 보다 더 유용함을 지시해준다.

• Annals of Clinical Neurophysiology
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• 제9권2호
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• pp.89-92
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• 2007

A 33-year-old women developed weakness in all limbs 3 days prior to admission. Motor examination showed decreased strength in all limbs, but sensory examination was normal. Deep tendon reflexes were areflexia. Electrophysiological examination showed conduction blocks with nearly normal conduction velocities and terminal latencies in motor nerves and normal amplitudes and velocities in sensory nerves. Her serum was positive for IgG antibodies to gangliosides GM1, GD1b, and galactocerebroside. Acute motor conduction block neuropathy may be another variant of Guillain-Barre syndrome.

• 한국자원식물학회지
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• 제22권6호
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• pp.528-534
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• 2009

The study of germination and seedling growth characteristics of Neem under different soil and environment conditions was undertaken. The seed germination started 8 days after sowing in commercial bed soil, whereas, delayed germination was observed in sandy-loam (15 days) and sandy (19 days) soil. The highest germination (73.33%) was observed in commercial bed soil in green house, whereas, the lowest germination was observed in sandy soil (16.67%) and sandy-loam soil (8.33%). The seeds in the open field (sandy soil) also showed poor (10%) germination. The mean number of germination seed/day (GD) and seed germination vigor rate (GV) both were highest in the commercial bed soil with 0.733% and 16.67% respectively in the green house, whereas sandy and sandy-loam soil in green house and open field (sandy soil) all showed much lower GD and GV values. The seedling characteristics of nursery revealed that the seedling grown in the growth chamber in commercial bed soil was significantly higher in all the parameters comparing to others grown in green house and open field. The growth was nearly 7 fold in the chamber compared to that of the green house nursery observed in three months old seedlings. Likewise, HPLC analysis revealed that the green house grown seedling contain higher quantity of pigments compare to the chamber grown seedlings. Among the soils used the commercial soil alone or in combination with sandy and sandy-loam soil in the ratio of 2:1:1 respectively with the temperature of $27{\pm}2^{\circ}C$ showed better for Neem nursery preparation.

• Transactions on Electrical and Electronic Materials
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• 제15권5호
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• pp.253-256
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• 2014

$Pb(Zr_{0.52}Ti_{0.48})O_3$ thin films of $1.5{\mu}m$ thickness were grown on $Pt/Ti/Gd_3Ga_5O_{12}$ substrate by RF magnetron sputtering at annealing temperatures ranging from $550^{\circ}C$ to $700^{\circ}C$. We evaluated the residual stress, by using a William-Hall plot, as a function of the annealing temperatures of PZT thin film with a constant thickness. As a result, the residual stresses of PZT thin film of $1.5{\mu}m$ thickness were changed by varying the annealing temperature. Also, we measured the hysteresis characteristic of PZT thin films of $1.5{\mu}m$ thickness to evaluate for application of an optoelectronic device.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2012년도 춘계학술발표대회
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• pp.58.2-58.2
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• 2012

Heavy hydrocarbon reforming is a core technology for "Dirty energy smart". Heavy hydrocarbons are components of fossil fuels, biomass, coke oven gas and etc. Heavy hydrocarbon reforming converts the fuels into $H_2$-rich syngas. And then $H_2$-rich syngas is used for the production of electricity, synthetic fuels and petrochemicals. Energy can be used efficiently and obtained from various sources by using $H_2$-rich syngas from heavy hydrocarbon reforming. Especially, the key point of "Dirty energy smart" is using "dirty fuel" which is wasted in an inefficient way. New energy conversion laboratory of KAIST has been researched diesel reforming for solid oxide fuel cell (SOFC) as a part of "Dirty energy smart". Diesel is heavy hydrocarbon fuels which has higher carbon number than natural gas, kerosene and gasoline. Diesel reforming has difficulties due to the evaporation of fuels and coke formation. Nevertheless, diesel reforming technology is directly applied to "Dirty fuel" because diesel has the similar chemical properties with "Dirty fuel". On the other hand, SOFC has advantages on high efficiency and wasted heat recovery. Nippon oil Co. of Japan recently commercializes 700We class SOFC system using city gas. Considering the market situation, the development of diesel reformer has a great ripple effect. SOFC system can be applied to auxiliary power unit and distributed power generation. In addition, "Dirty energy smart" can be realized by applying diesel reforming technology to "Dirty fuel". As well as material developments, multidirectional approaches are required to reform heavy hydrocarbon fuels and use $H_2$-rich gas in SOFC. Gd doped ceria (CGO, $Ce_{1-x}Gd_xO_{2-y}$) has been researched for not only electrolyte materials but also catalysts supports. In addition, catalysts infiltrated electrode over porous $La_{0.8}Sr_{0.2}Ga_{0.8}Mg_{0.2}O_3-{\delta}$ and catalyst deposition at three phase boundary are being investigated to improve the performance of SOFC. On the other hand, nozzle for diesel atomization and post-reforming for light-hydrocarbons removal are examples of solving material problems in multidirectional approaches. Likewise, multidirectional approaches are necessary to realize "Dirty energy smart" like reforming "Dirty fuel" for SOFC.

• 한국세라믹학회지
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• 제45권12호
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• pp.782-787
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• 2008

Ni-ceria cermets have been extensively investigated as candidates for the anode in intermediate-temperature solid oxide fuel cells. We have used the citric method to synthesize nanocomposite powders consisting of NiO (Ni metal content: $40{\sim}60%$ by volume) highly dispersed in $Ce_{0.9}Gd_{0.1}O_{1.95}$ (CGO). The microstructure characteristics and sintering behaviors of the nanocomposites were investigated. No impurity phases were observed and the shrinkage of these substrates matched well with that of a CGO electrolyte with a specific surface area of $11\;m^2/g$. Densification of the CGO electrolyte layer to $<5\;{\mu}m$ thickness was achieved by co-firing the laminated electrolyte with the porous NiO-CGO substrate at $1400^{\circ}C$ for 6 h.

• Journal of Nutrition and Health
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• 제28권4호
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• pp.345-354
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• 1995

Blenderized diets are not recommended because of difficulties in providing a constant content of nutrients, phoblems with viscosity and osmolarity, time needed for preparation, and increased risk of contamination. To determine the possibility of substituting commercial formulas for blenderized diets, 27 unconscious patients were randomized into two different groups : blenderized diet group(n=11) and commercial formula group(n=16). Blenderized diets were composed of food sources such as rice, milk, egg, juices and others, and its energy percentage of protein, fat, and carbohydrate was 15%, 30%, and 55%, respetively. Commercial enteral formulas provided 1 kcal/ml and the energy percentage of protein, fat and carbohydrate was 25%, 20% and 55% in greenbia(G) and 20%, 20%, and 60% in Greenbia-DM(GD), repectively. In commercial formula group, five patients with diarrhea, constipation, and high blood glucose level received GD, and the other eleven patients received G. All patients received their lipuid diet for 4 weeks through 16 French rubber nasogastric tube by bolus feeding 6 times daily. The patients in commercial formula group had a similar mean daily calorie intake to the patient in blenderized diet group, 32-34kcal/kg/d and 30-35kcal/kg/d, respectively. Patients given commercial formula gained an averge of 1.7kg in weight but those given blenderized diet lost an average of 2.6kg. There was a trend toward an increase in percent ideal body weight in commercial formula group(94$\pm$5 vs 99$\pm$6%). However, blenderized diet group showed a trend toward a decrease in percent ideal body weight(106$\pm$5 vs $101\pm$6%). The initial levels of total lymphocyte counts, serum albumin and tranferrin were below the normal rante, The mean daily protein intake was significanlty higher for commercial formula group(2.0-2.1g/kg/d) than for blenderized diet group(1.1-1.3g/kg/d). Patient fed cormmercial formula for 4 weeks showed a trend toward an increase in serum albumin(8.1%) and a significant increase in serum transferrin(32.1%) without increasing the levels of blood glucose. GOT, GPT, blood urea nitrogen and serum creatinine. In the blenderized diet group, however, no significant improvement were obseved in the concentration of serum albumin and transferin, compared to initial value. There was a trend toward a decrese in the level of hemoglobin and hematocrit in blenderized deit group but no significnat change in commercial formulas goups. All patients tolerated both diets well and no significant complications were encountered. The results indicate that the commercial enteral formulas tested in this study can be an effective substitution for blenderized diet in unconscious tube-fed patients.

• 환경위생공학
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• 제16권2호
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• pp.17-23
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• 2001

The objective of this study was to investigate the component ratio of gas generated at closed GD landfill site in MY city and the decomposition status of landfill gas, and was to examine and analyze the properties of the landfill gas. In addition, to provide basic data required to stabilize landfill earlier in the future, the study was to measure gas by landfill gas gauge and to analyze the properties of landfill gas based on documents. As a result of analyzing the properties, acquired follow results. 1. The main elements of landfill gas, $CH_4$ and $CO_2$ were respectively 25.02% and 22.325 on the average. 2. $NH_3$ and $H_2S$ were respectively 1.07 4.97 and 0.75 1.15 on the average. 3. Generated gas was different depending on water, pH properties of MSW(Munticipal Solid Wastes) and their decomposition rate. Furthermore, when measured the temperature of room to inspect landfill gas, the temperature was $22{\;}-{\;}30^{\circ}C$ in the average.

• 한국콘텐츠학회논문지
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• 제15권11호
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• pp.298-306
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• 2015

본 연구는 진단용 X선 검사 시 사용하고 있는 부가필터의 재질(Cu, Ni, CaWO4, Gd+Ba)을 다양화하여 그에 따른 검사실 내의 공간선량을 평가 한 후 적합한 재질을 찾아 제시하고자 하였다. 실험은 몬테칼로 기법을 바탕으로 하는 MCNPX 프로그램을 사용하여 흉부와 복부검사를 선택하여 모의실험을 진행하였다. 그 결과 각 재질별 선량은 모의피폭체가 위치한 곳을 중심으로 반경 50 cm 인 지점의 평균 산란선량은 모의피폭체 표면선량의 약 62%, 반경 100 cm인 지점은 평균 약 47% 정도 측정되었다. 결과에 따라 현재 상용화 되어 있는 Al 재질을 Cu, Ni 재질이 충분히 대체가능 할 것으로 판단된다. 다만 원자번호와 밀도의 차이로 인하여 그 두께를 Al의 약 1/10 정도로 조정을 해서 사용하면 적합할 것이다.

• 한국지능시스템학회논문지
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• 제15권6호
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• pp.720-729
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• 2005

본 논문에서는 미지의 비선형 시스템을 제어하기 위해 웨이블릿 신경 회로망을 이용한 간접 적응 제어기를 설계한다. 제안 된 간접 적응 제어기는 웨이블릿 신경 회로망을 이용한 동정 모델과 제어기로 구성된다. 여기서 동정 모델과 제어기에 사용되는 웨이블릿 신경 회로망은 시간과 주파수에 대한 정보를 동시에 포함하는 웨이블릿의 특성을 가지고 있기 때문에 다층구조 신경회로망과 방사 기저 함수 신경회로망에 보다 더 빠른 수렴특성을 보인다. 웨이블릿 신경 회로망의 학습방법은 경사 하강법, 유전알고리듬, DNA 기법등 여러 가지가 있으나, 본 논문에서는 확장 칼만 필터를 기반으로 한 학습 방법을 제안한다. 확장 칼만 필터 학습 방법은 계산이 복잡하기는 하지만 학습되어 갱신되는 파라미터의 이전 데이터 정보를 이용하는 특성 때문에 매우 빠른 수렴 특성을 보인다. 본 논문에서는 Buffing 시스템과 1축 머니퓰레이터에 대한 컴퓨터 모치실험을 통해 제안한 확장 칼만 필터 학습 방법을 이용한 간접 적응 제어기가 일반적인 경사 하강법을 이용한 경우보다 우수함을 보인다.