• 한국재료학회지
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• 제6권3호
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• pp.333-340
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• 1996

p-type(100) 실리콘 기판과 TiN(50nm)/Si 기판에 dimethylethylamine alane(DMEAA)을 반응소스로 하여 알루미늄을 증착시켜 증착온도와 유량, 반송가스 종류에 따른 방향성, 증착속도, 미세구조 변화에 대해 연구하였다. 알루미늄의 증착속도는 기판온도, 반송가스 종류 및 유량에 따라 100-650mn/min으로 다양하게 조절되었다. DMEAA의 증착 활성화에너지는 TiN 기판에서는 약 0.leV이었고 Si와 SiO2 기판에서는 각각 약 0.23eV, 0.24eV이었다. 알루미늄 박막의 방향성은 증착속도의 감소에 따라 (200)에서 (111)방향으로 변하였다. 증착된 알루미늄 박막의 불순물 함량은 산소의 경우 0.2at%, 탄소의 경우 1.8at.%이었다. DMEAA 소스에 의한 알루미늄의 증착속도는 반송가스가 Ar 일 때 보다 H2 가스를 사용하면 증착속도가 크게 증가하였으며 이는 반송가스에 의해 SiO2표면의 흡착 H 농도가 증가하고 흡착 H가 소스 가스와 반응하여 핵생성 site 로 작용하는 것으로 생각된다. 알루미늄 박막의 비저항은 표면 미세조직에 크게 영향을 받으며 그 값은 약 3-7$\mu$$\Omega$cm이었다.

• Nuclear Engineering and Technology
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• 제52권7호
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• pp.1367-1379
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• 2020

The small modular sodium-cooled fast reactor (SMSFR) is an important component of Generation-IV reactors. The objective of this work is to improve the reactivity control in SMSFR by using innovative systems, including burnable poisons and optimized control rods. SMSFR with MOX fuel usually exhibits high burnup reactivity loss that leads to high excess reactivity and potential fuel melting in control rod withdrawal (CRW) accidents, which becomes an important constraint on the safety and economic efficiency of SMSFR. This work applies two types of burnable poisons in a SMSFR to reduce the excess reactivity. The first one homogenously loads minor actinides in the fuel. The second one combines absorber and moderators in specific assemblies. The influence of burnable poisons on the core characteristics is discussed and integrated into the analysis of CRW accidents. The results show that burnable poisons improve the safety performance of the core in a significant way. Burnable poisons also lessen the demand for the number, absorption ability, and insertion depth of control rods. Two optimized control rod designs with rare earth oxides (Eu₂O₃ and Gd₂O₃) and moderators are compared to the conventional design with natural boron carbide (B₄C). The optimized designs show improved neutronic and safety performance.

• Asian-Australasian Journal of Animal Sciences
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• 제17권8호
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• pp.1139-1144
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• 2004

In Exp. 1, a total of 36 pigs (6.55$\pm$0.10 kg average initial body weight and 21 d average age) were used in a 14 d growth study to determine the effects of replacing spray-dried plasma protein (SDPP) with spray-dried egg protein containing specific egg yolk antibody (SDEP) on growth performance and nutrient digestibility in weaned pigs. The pigs were blocked by weight and assigned to treatments based on sex. There were three pigs per pen and four pens per treatment. Dietary treatments were 0, 3, or 6% SDEP and contained 6, 3, or 0% SDPP, respectively. Through the entire experimental period, average daily gain (ADG), average daily feed intake (ADFI), and gain/feed tended to decrease as the concentration of SDEP increased in the diets. However, there were no significant differences among the treatments (p>0.05). As the addition of SDEP in the diets increased, apparent digestibilities of dry matter (DM) and nitrogen (N) were decreased without significant (p>0.05). For Exp. 2, 36 pigs (2.63$\pm$0.04 kg average initial body weight and 10 d average age) were used in a 14 d growth study to determine the effects of antibiotic replacement with SDEP on growth performance and nutrient digestibility in early-weaned pigs. The pigs were blocked by weight and assigned to treatments based on sex. There were three pigs per pen and four pens per treatment. Dietary treatments included 1) ANTIBIOTIC (corn-dried whey-soybean meal based diet+0.08% antibiotics, 4 mg of tiamuline hydrogen fumarate; 10 mg of sulfadimidine per kg of complete diet), 2) SDEP0.1 (corndried whey-SBM based diet+0.1% SDEP), and 3) SDEP0.2 (corn-dried whey-SBM based diet+0.2% SDEP). ADG and gain/feed of pigs fed the SDEP0.2 diet were higher than for pigs fed the ANTIBIOTIC diet without significant (p>0.05). Pigs fed the diet with SDEP0.2 tended to have increased apparent digestibilities of DM and N compared to pigs fed the ANTIBIOTIC diet without significant (p>0.05). In conclusion, the dietary SDEP seemed to be partial replacing the SDPP portion of high nutrient dense diet for weaned pigs. Also, dietary SDEP seemed to be approximately 0.2% or more when the pigs fed the antibiotic-free diet for early-weaned pigs.

• Applied Biological Chemistry
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• 제21권1호
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• pp.58-62
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• 1978

인삼(人蔘)의 연근별(年根別) 건물중(乾物重)과 삼요소(三要素) 흡수량(吸收量)및 기타(其他)미량원소등(微量元素等)을 분석(分析)하여 인삼식물(人蓼植物)의 양분(養分) 요구상(要求相)과 영양생리(營養生理) 연구(硏究)의 기초자료(基礎資料)를 얻고자 과천인삼시험장(果川人蔘試驗場) 산(産) $1{\sim}6$년근(年根) 인삼(人蔘)을 대상(對象)으로 조사(調査)한 결과(結果)는 다음과 같다. 1. 인삼(人蔘)의 건물중(乾物重) 및 T/R율 T/R율은 저년근(低年根)이 적었고 4년근(四年根)이 0.52로 가장컸다. 이는 4년근(四年根)에서 지상부(地上部) 생육신장(生育伸長)이 왕성(旺盛)하기 때문인 것으로 사료(思料)되며 지상부(地上部) 및 근(根)의 건물중(乾物重)도 4년근(年根)에서 현저하게 증가(增加)하였다. 2. 인삼(人蔘)의 무기성분(無機成分)의 함량(含量) 가. 질소(窒素)는 엽근(葉根)에 비(比)해 경(莖)이 적었고 인산(燐酸)은 근(根), 경(莖), 엽순(葉順)으로 많으며 가리(加里)는 각년근(各年根) 공히 경(莖)에 많았고 특(特)히 N.P에 비(比)해 가리(加里)의 함량(含量)이 많았다. 나. 석회(石灰), 고토(苦土)는 엽(葉)과 경(莖)에 많았고 Fe, Mn은 각년근(各年根) 공히 엽(葉)에 많은 경향이며 Fe는 엽(葉)에 $1000{\sim}2000ppm$, 근(根) $350{\sim}750ppm$ Mn은 근(根)에 $40{\sim}80ppm$정도 함유(含有)되어 있었다. 다. Zn, Mn의 함량(含量)이 높은것은 Zn Mn 성분(成分)을 함유(含有)한 다이젠 약제살포(藥劑撤布)에 기인(基因)된 것으로 추측된다. 3. 6년근(年根)까지의 삼요소(三要素) 총흡수량(總吸收量)은 N;10.24kg, $P_2O_5;2.31kg$, $K_2O;14.86kg$으로서 가리(加里)의 흡수량(吸收量)이 대단히 많았다.

• Wind and Structures
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• 제3권1호
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• pp.23-40
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• 2000

In the early morning hours of February 23rd, 1998, seven large tornadoes ravaged central Florida. A total of 42 people were killed and millions of dollars of damage was done. A strip mall and other commercial structures sustained considerable damage and several residential areas were completely destroyed. Based on field observations, the paper examines the causes and sequence of structural failure for the masonry single family homes. Wind speeds are estimated based on the observed damage, and compared to the meteorological data. Finally, recommendations are given that could help to eliminate or reduce similar failures in the future. It was found that with simple, cost effective measures, most if not all of the damage could have been prevented.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.1281-1282
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• 2007

Effect of tension coating on reducing iron losses of thin grain-oriented 3% Si-Fe steel sheets was investigated. Conventional grain-oriented electrical steel sheets have a forsterite coating layer and a tension coating layer in order to apply tensile stress to the rolling direction of the sheets. However the proposed coating method in this paper is to form only a tension coating layer on the both surfaces of the sheets. Iron losses with the tension coating were reduced by 8% under the condition of 1.7 T and 60 Hz. Consequently the proposed tension coating is applicable to $80{\mu}m$-thick 3% Si-Fe steel sheets.

• 한국초전도ㆍ저온공학회논문지
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• 제10권3호
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• pp.14-18
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• 2008

This paper deals with the conceptual design and characteristic analysis of core type superconducting motor using iron cores in the field. As the objective function of conceptual design, the flux quantity per pole is selected. In order to reduce the quantity of superconductors, the variations of flux quantity per pole by changing the design variables and area are investigated. Finally, the quantity of superconductors between air-cored and core type superconducting motor is compared under the same motor capacity. In addition, the dimensions and volumes of motors are compared.

• Applied Biological Chemistry
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• 제15권2호
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• pp.169-173
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• 1972

한국산(韓國産) 유자(柚子)의 지역별산물(地域別産物) 5종(種)에 대(對)하여 일반성분(一般成分)과 총산(總酸) 및 무기성분(無機成分)을 분석(分析)하여 부위별(部位別)로 함유량(含有量)을 조사검토(調査檢討)하였고 유자원토양(柚子園土壤)의 이화학적성질(理化學的性質)을 분석(分析)하여 토성(土性)을 조사(調査)하고 pH 및 유기물(有機物)을 비롯하여 몇 가지 성분(成分)을 분석비교(分析比較)하여 다음과 같은 결과(結果)를 얻었다. 1. 과피(果皮)와 과육(果肉)의 구성비율(構成比率)은 과피(果皮)가 49%로서 전과(全果)의 약(約) 반량(半量)을 점유(占有)하고 있으며 일반적(一般的)으로 타감귤류(他柑橘類)에 비(比)하여 과피율(果皮率)이 크다고 볼 수 있다. 2 총산(總酸)의 함유량(含有量)은 평균(平均) 과피(果皮)가29.29me, 과육(果肉)이 39.79me로서 과육(果肉)에 더 많이 함유(含有)되어 있다. 3. 과피(果皮), 과육중(果肉中)의 무기성분(無機成分)은 양자(兩者)가 다음과 같은 순위(順位)로 함유(含有)되어 있다. $CaO>K_2O>MgO>P_2O_5>SO_4$ 4. MgO와 $SO_4$ 함유량(含有量)이 많은 것은 조단백질(粗蛋白質)과 조지방(粗脂肪)의 양(量)이 많이 함유(含有)되어 있음을 알 수 있다. 5. 과피형성(果皮形成)에 토양중(土壤中) 가리량(加里量)이 크게 영향(影響)을 미친다는 것은 감귤(柑橘)에 뿐 아니라 유자(柚子)에도 해당(該當)됨을 확인(確認)하였다. 6. 유자(柚子)가 생육(生育)할 수 있는 조건(條件)은 여러 가지 환경조건(環境條件)에 따라 영향(影響)을 받으나 그 중(中) 토양(土壤)에 관(關)하여는 식양토(埴壤土)가 가장 적당(適當)함을 알았다. 7. 토양(土壤)의 pH는 범위(範圍)가 일정(一定)한 것이 아니나 분석결과(分析結果) $pH\;5.05{\sim}7.2$의 범위(範圍)로 대체(大體)로 미산성(微酸性)이었다. 8. 토양중(土壤中) 유기물(有機物)과 전질소(全窒素)의 함유량(含有量)이 많은 것은 유자일반성분중(柚子一般成分中) 조단백질(粗蛋白質)과 조지방(粗脂肪)의 양(量)이 많이 함유(含有)되어 있었다.

• 한국진공학회지
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• 제20권2호
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• pp.135-140
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• 2011

Be을 도핑한 p형 GaSb:Be 에피층의 광여기 발광(PL) 스펙트럼(20 K)의 도핑밀도에 따른 변화를 조사하여, Be 억셉터의 근원을 분석하였다. 도핑을 증가시키면 PL 피크가 고에너지로 변위하고 반치폭은 줄어드는 경향을 보이다가, 밀도가 ${\sim}10^{17}cm^{-3}$ 이상에서 피크 에너지는 오히려 저에너지로 변위하고 반치폭이 늘어나는 현상을 관측하였다. 3개 피크로 분리한 PL 스펙트럼의 적분 PL 강도 변화를 통하여, 도핑 증가에 따라 $Be[Be_{Ga}]$ 준위(0.794 eV)는 감소하는 반면 진성결함에 기인한 $A[Ga_{Sb}]$ 피크(0.778 eV)와 함께 Be과 A 사이에 위치하는 새로운 $Be^*$ 준위(0.787 eV)가 증가하기 때문으로 분석되었다. 이것은 Be을 도핑한 p-GaSb:Be 에피층에는 Be 얕은준위(${\Delta}E=16meV$)와 Be과 A 결함준위가 결합한 $Be^*[Ga_{Sb}-Be_{Ga}]$의 복합준위(${\Delta}E=23meV$)가 공존하기 때문으로 논의하였으며, ${\sim}10^{17}cm^{-3}$ 이상 도핑할 경우에는 Be 준위가 다소 감소할 수 있음을 보였다.

• Asian Pacific Journal of Cancer Prevention
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• 제17권5호
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• pp.2565-2571
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• 2016

A cross-sectional survey was conducted among 730 participants from 4 rural districts of Nakhon Ratchasima province, Thailand, with a reported high incidence of liver fluke infection. This study was aimed to examine and evaluate the nutritional status in relation to Opisthorchis viverrini infection. Participants were purposive selected from Chum Phuang, Mueang Yang, Bua Yai, and Kaeng Sanam Nang districts. Stool samples were prepared by Kato Katz technique and then assessed by microscopy. Anthropometry was evaluated according to the body mass index from weight and height. Descriptive statistics and Spearman rank correlation coefficients were used to evaluate the association between the nutritional status and O. viverrini infection. Of 1.64% infected with O. viverrini the highest proportions were found in age groups ${\geq}61$ and 41-50 years old, Mueang Yang district. The majorities of participants had normal weight (32.2%), followed by class II obesity (28.1 %), class I obesity (21.8%), underweight (10.3%), and class III obesity (8.63%). Nutritional status with class II obesity (rS=0.639, p<0.01) and class I obesity (rS=0.582, p<0.05), had moderately statistical significant correlations with O. viverrini infection. Meanwhile, normal weight (rS=0.437, p<0.05) and class III obesity (rS=0.384, p<0.05) demonstrated lower statistical significance. These findings raise the possibility that infection with O. viverrini may contribute to fat deposition and thereby have long-term consequences on human health. Further studies are needed to better understand whether O. viverrini contributes directly to fat deposition and possible mechanisms.