• 전기학회논문지
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• 제63권9호
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• pp.1233-1238
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• 2014

In this thesis, it is investigated the characteristics of Dye Sensitized Solar Cell (DSSC) according to variation of $TiO_2$ thickness (6, 12, 18, and $24{\mu}m$) and three distinct $TiO_2$ sintering temperatures (350, 450 and $550^{\circ}C$) by XRD, SEM, I-V and UV-Vis spectrophotometer. According to sintering temperature, $TiO_2$ was transformed into the anatase structure at $350^{\circ}C$, rutile structure at $550^{\circ}C$ and further into the two structure at $450^{\circ}C$. With increasing thickness up to $18{\mu}m$ and sintering temperature up to $450^{\circ}C$, respectively, the irradiance rate increased in the range of 9~26 percent and 2.80~5.10 percent. Whereas a further increase to $24{\mu}m$ and $550^{\circ}C$, the irradiance rate decrease in the range of 4~11 percent and 30~47 percent. The conversion efficiency increased in the range of 2.80~5.01 and 3.03~5.01 with increasing thickness up to $18{\mu}m$ and sintering temperature up to $450^{\circ}C$. By contrast, increase to $24{\mu}m$ and $550^{\circ}C$, the conversion efficiency decreased in the range of 3.31~5.01 and 2.80~3.89, respectively. The DSSC that thickness of $TiO_2$ were $18{\mu}m$ and sintered at $450^{\circ}C$ exhibited the most excellent characteristics, in which open-circuit voltage, short-circuit current, Fill Factor and conversion efficiency are 0.69 V, $11.4mA/cm^2$, 0.64 and 5.01%, respectively.

• Journal of Nutrition and Health
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• 제3권3호
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• pp.149-159
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• 1970

This study is to investigate the status of anemia, especially iron deficiency anemia among pre-school children in rural area in Korea. The survey was conducted in Sang-dae Ri, Yusong Myon, Daedok Gun, Chung Chong Nam-Do from July 30 th to August 12th, 1968. The measurements were done of height, weight, hematologist and biochemical levels on ninety-two pre-school children, 47 male, and 45 female, one to six years of age. Hemoglobin was determined by the method of cyanmethemoglobin and hematocrit by micro hematocrit centrifuge. The determination of serum iron, iron-binding capacity was done by the method of Ramsay using bathophenanthroline and the serum albumin was determined by Biuret Reaction. The results of this study are as follows: 1) 54.4 percent of the pre-school children weighed less than 90 percent of the Korean General Standard Weight level. 2) The average hemoglobin level was $11.0{\pm}1.57gm/100ml$, 38.0 percent of the children were anemic with less than 1.0gm/100ml. Of the anemic children 60 percent were below the Korean General Standard Weight level. 3) 27.5 percent of the pre-school children were found to have below 32 percent of a hematocrit values and 28.0 percent showed less than 33 percent in M.C.H.C. These results showed that the incidence of hypochromic anemia in these pre-school children was high. 4) 37.9 percent of these children had a serum iron level less than $50{\mu}g/100ml\;and\;31.0\;percent\;had\;a\;TIBC\;above\;400{\mu}g$ while 48.3 percent showed a transferrin saturation lower than 15 percent. On the basis of these findings, it is concluded than the cause of this anemia was iron deficiency. 5) In this group there was a little evidence of low total serum protein levels. However, 10.4 percent of the children had a deficient serum albumin level, below 2.80 gm/100ml while 51.7 percent had a low level, less than 3.50gm/100ml, and 34.5 percent of the children had a low level of TIBC, less than $350{\mu}g/100ml$, and considering these facts, it is suggested that some of the anemias have a multiple causes through protein deficiency and repeated chronic infection apart from iron deficiency.

• Asian-Australasian Journal of Animal Sciences
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• 제16권6호
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• pp.794-799
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• 2003

A study was conducted on 2102 records of 808 crossbred cows of various genetic groups maintained under 'All India Coordinated Research Project on Cattle' at C C S Haryana Agricultural University, Hisar, over 25 years period (1968-1993) with an objective to assess and compare the amount of percent improvement and heterotic effect for different performance traits in various genetic groups produced under this programme. Survivability sharply and significantly declined from 1/2 to $3/4^th$ bred and further from $3/4^th$ to inter-se bred. This may be due to periodic and management differences in addition to the higher level of exotic inheritance and decreased heterotic effect over the filial generations. Jersey and Holstein Friesian crosses among 1/2 breds and their 50% inheritance among $3/4^th$ and inter-se breds had highest improvement and heterosis in reproduction and production traits respectively. Among inter se bred genetic groups, BFH (I) had no recombination loss in SP and CI, while FJH (I), JFH (I) and FBH (I) had on recombination loss in AFC, LY, LL and PE. The crossbreeding of zebu cows with exotic breeds brings about spectacular improvement in comparison to the performance of zebu breed, while conventional selection over several generation would lead to only modest improvement. In addition to additive effect, there was sufficient heterosis in Jersey crosses for reproduction and Holstein Friesian crosses for production performance. Three breed crosses with exotic inheritance between 50 and 75 percent incorporating genes (25 to 50%) from both of these breeds is the best combination for stabilization.

• 대한화학회지
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• 제20권6호
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• pp.525-532
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• 1976

CO2/KOH catalysis에 의해 2-pyrrolidone과 ${\varepsilon}$-caprolactam의 음이온 중합을 시도하였으며 이 polymer의 물리적 성질을 조사하였다. 2-Pyrrolidone 중합의 경우는, KOH의 농도가 8mole%이상이고 $CO_2/KOH$ mole ratio가 0.45일 때 percent conversion이 가장 높았으며 $50^{\circ}C$가 최적의 온도임을 알았다. ${\varepsilon}$-Carprolactam의 중합에 있어서는 80 ∼ $90^{\circ}C$에서 percent conversion이 낮았고, 150 ∼ $180^{\circ}C$의 온도에서는$ CO_2/KOH$ mole ratio에 크게 관계없이 높은 percent conversion을 얻을 수 있었다. 이들 polymer의 고유점도는 대략 2.0 ∼ 5.0dl/g의 높은 값이었다.

• Clinical and Experimental Pediatrics
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• 제48권6호
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• pp.606-613
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• 2005

목 적 : APSGN은 소아에서 흔히 볼 수 있는 급성 사구체 신염의 하나로, 대부분의 환자에서 급성기 이후 완전한 회복을 보이지만, 소수의 환자에서는 급성기 합병증으로 사망하거나, 이후에 만성 신부전으로 진행하기도 하는 것으로 알려져 있다. 최근 과거에 비하여 발생빈도가 줄어들었으나, 여전히 소아에서 흔히 볼 수 있는 신질환으로 최근 10년간의 임상 양상을 살펴보고, 과거의 보고들과의 차이를 알아보고자 하였다. 방 법 : 1994년 1월부터 2003년 12월까지 서울아산병원 소아과에서 APSGN으로 진단받고 입원 또는 외래 치료를 시행한 105명의 환아를 대상으로 후향적으로 의무기록을 검토하여 연구하였다. 결 과 : APSGN으로 진단받은 환아들의 남녀비는 2 : 1이었고, 평균연령은 $8.5{\pm}2.6$세였다. 연평균 발생 비율은 $10.5{\pm}4.9$였고, 연중 발생을 살펴보면 대부분(60.0%)의 환아가 10월에서 1월 사이에 발생하였다. 내원 당시 부종이 82명(78.1%), 육안적 혈뇨 70명(66.7%), 고혈압 50명(47.6%), 핍뇨 22명(20.9%)에서 나타났고, 현미경적 혈뇨 105명(100%), ASO 양성 99명(94%), C3 감소 96명(91.45), 단백뇨 67명(63.8%)에서 나타났고, BUN이 증가한 경우가 38명(26.2%)였다. C3가 감소하였던 96명 중 70명(75.3%)에서 8주째 정상으로 회복되었다. 22명의 환아에서 신장조직 검사를 시행하였다. 급성기 증상은 대부분의 환아에서 1-2주 사이에 소실되었다. 결 론 : APSGN의 임상양상은 과거의 연구들과 비교하여 큰 차이가 없었고, 급성기 회복률 및 단기예후는 우수하였다.

• 미생물학회지
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• 제9권2호
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• pp.55-60
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• 1971

Among 50 yeasts of red pepper paste isolated and identified in the previous report, 12 strains of yeast which possess osmophilic and non-film characteristics were examined their growth rates and alcohol fermentation ability in red pepper medium. 5 strains of yeast possessing powerful growth rates and excellent alcohol fermentation ability were selected as excellent yeasts in this experiment. And their cultural conditions, salt resistance and red pepper concentration upon the growth were examined in this report. The results obtained were as follows ; 1) Among 12 strains of yeast, Saccharomyces cerevisiae group II(strain $D_1$), Saccharomyces oviformis($D_2$), Saccharomyces steineri($M_3$), Saccharomyces rouxii($D_9$) and Saccharomyces mellis($G_8$) were selected as excellent yeasts. 2) Among 5 strains of yeast selected, the strain $D_1$ and $D_2$showed the best alcohol fermentation ability and the best fermentative flavour. 3) The optimum temperature for growth of the strain $D_1$ and $D_2$ was $25^{\circ}C$$M_3$, $D_9$ and $G_8$ $30^{\circ}C$$D_1$ and $D_2$ was $62^{\circ}C$$M_3$,$D_9$ and $G_8$ ws 60.deg.C with treatment for 10 minutes. 4) The optimum pH for growth of all strains was around 5.0. 5) The strain $D_1$ and $M_3$were grown exceedingly well on the emdia containing 3 percent of NaCl and $D_2$,$D_9$ and $G_8$ on the media containing 6 percent of NaCl. 6) In the case of 5 percent of red pepper liquor added 5 percent of glucose was more nutritional than in the case of 5 percent glucose only. However, the growth rates of yeasts were restrained by the increase of red pepper concentration.

• 한국작물학회지
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• 제20권
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• pp.122-133
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• 1975

In recent years, farmers have substituted urea for ammonium sulfate as nitrogen fertilizer in their crop production. Since crops can not take urea itself directly as it is, we attempted to determine the amount of decomposition of urea in soil. It was observed that 25 percent of urea which had initially mixed with soil was decomposed in 10 days at 15$^{\circ}C$ and 80 percent in 2 days at $25^{\circ}C$. Therefore, it was considered that large amount of urea could be lost in cool season and cool areas. In the other experiment, ammonium sulfate, as a source of sulfur, was so mixed with urea that the ratio of sulfur to nitrogen would be 15 percent. Small amount of dolomite was also added to this mixture and the resulting fertilizer was applied on the rice plants. Eight percent of yield increase was obtained together with the increased protein content in brown rice.

• Journal of the Korean Wood Science and Technology
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• 제22권3호
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• pp.32-38
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• 1994

The methods in wood processing are so limited at present that a scope of its utilization is restricted. This often makes wood itself less valuable as a material comparing with other materials, that is, plastics, metals, and glass. Such differences are due to a lack of plasticity in wood, i.e. it cannot be melted, dissolved, or softened sufficiently for molding. However, once plastic properties are added to wood, it becomes more useful material. This further broadens the method in wood processing to a variety of fields. In this way, wooden material which is limited in use can be modified into a high quality product with additional value. Furthermore, utilization of wastes from wood, for example, would be made viable. In this study, thermoplasticization was carried out by benzylation of wood(sawdust). Various factors those affect the reaction were tested to produce benzylated wood with different degrees of substitution. Reaction temperature and time were the quite important factors. Optimum reaction temperature was 110$^{\circ}C$, and weight percent gains(WPG) of final products increased gradually with the increase of reaction time. The pretreatment (or preswelling) of wood with alkaline solution had a critical effect on benzylation. and the concentration of alkaline solution should be above 30% to obtain high weight percent gain. The thermal flow temperature of the benzylated wood decreased with the increase in weight percent gain, that of 80% weight percent gain is about 200$^{\circ}C$.

• 한국수소및신에너지학회논문집
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• 제8권2호
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• pp.91-97
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• 1997

The goals of this research are to understand the $NO_x$ emission in direct injected diesel engine with premixed hydrogen fuel. Hydrogen fuel was supplied into the test engine through the intake pipe. Amount of hydrogen-supplemented fuel was 70 percent basis heating value of the total fuel. The effects of intake air temperature on $NO_x$ emission were studied. The intake air temperature was controlled by flow rate of liquid nitrogen. The major conclusions of this work include : (i) the tested engine was run without backfire under 70 percent hydrogen fuel supplemented. (ii) radicals of nitrogen gas in the intake pipe were increased by 30 percent and cylinder gas temperature was decreased by 24 percent as the intake air temperature were changed from $23^{\circ}C$ to $0^{\circ}C$ ; and (iii) $NO_x$ emission per unit heating value of supplied fuel was decreased by 45 percent with same decrease of intake air temperature.

• 원예과학기술지
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• 제18권3호
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• pp.327-333
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• 2000

Priming시 처리기간과 처리온도가 종자의 발아성에 미치는 효과를 구명하고자 하였다. 이때 사용한 약제는 당근은 -0.50MPa PEG 8000, 상추는 50mM $K_3PO_4$, 양파는200mM $KH_2PO_4$, 파는 100 mM $Ca(NO_3)_2$였으며, 작물별로 처리기간은 12시간에서 5일, 처리온도는 $10^{\circ}C$에서 $25^{\circ}C$까지로 달리하였다. 당근의 발아율은 종자처리와 처리온도에 따른 유의차가 있었으며, $20^{\circ}C$에서 3일 priming시 T50 및 MDG 단축에 효과적이었다. 그리고 $20^{\circ}C$에서 4일처리시 priming 용액속에 유근이 14% 돌출되었다. 상추의 발아율은 종자처리와 처리기간에 따라 유의차가 있었다. $20^{\circ}C$에서 2일 priming시 발아율이 높고 T50과 MDG 단축에 효과적이었으며 유근돌출은 발생하지 않았다. 양파의 발아율은 종자처리, 처리기간 및 처리온도 모두에서 유의차가 있었다. $10^{\circ}C$ 혹은 $15^{\circ}C$에서 3일, 4일 및 5일 처리시 발아율은 향상되지 않았으나 T50과 MDG 단축에는 효과적이었으나, priming 기간이 3일에서 5일로 길어질수록 발아율은 낮아졌다. 파의 발아율은 처리기간 및 처리온도에 따른 유의차가 없었지만, $15^{\circ}C$에서 4일 처리시 T50 및 MDG 단축에 효과적이었고 $15^{\circ}C$ 혹은 $20^{\circ}C$에서 처리기간이 길어질수록 유근돌출이 많이 발생되었다.