• 제목/요약/키워드: rings with Property (A)

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8인치 Si Power MOSFET Field Ring 영역의 도핑농도 변화에 따른 전기적 특성 비교에 관한 연구 (Characterization and Comparison of Doping Concentration in Field Ring Area for Commercial Vertical MOSFET on 8" Si Wafer)

  • 김권제;강예환;권영수
    • 한국전기전자재료학회논문지
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    • 제26권4호
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    • pp.271-274
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    • 2013
  • Power Metal Oxide Semiconductor Field Effect Transistor's (MOSFETs) are well known for superior switching speed, and they require very little gate drive power because of the insulated gate. In these respects, power MOSFETs approach the characteristics of an "ideal switch". The main drawback is on-resistance RDS(on) and its strong positive temperature coefficient. While this process has been driven by market place competition with operating parameters determined by products, manufacturing technology innovations that have not necessarily followed such a consistent path have enabled it. This treatise briefly examines metal oxide semiconductor (MOS) device characteristics and elucidates important future issues which semiconductor technologists face as they attempt to continue the rate of progress to the identified terminus of the technology shrink path in about 2020. We could find at the electrical property as variation p base dose. Ultimately, its ON state voltage drop was enhanced also shrink chip size. To obtain an optimized parameter and design, we have simulated over 500 V Field ring using 8 Field rings. Field ring width was $3{\mu}m$ and P base dose was $1e15cm^2$. Also the numerical multiple $2.52cm^2$ was obtained which indicates the doping limit of the original device. We have simulated diffusion condition was split from $1,150^{\circ}C$ to $1,200^{\circ}C$. And then $1,150^{\circ}C$ diffusion time was best condition for break down voltage.

폴리머 애자의 End-fitting 설계 및 성능 평가기술 (End-fitting Design and Performance Evaluation of Polymer Insulator)

  • 조한구;이운용;한세원;한동희;지원영;여학규;강두원;천종욱;이형규
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 춘계학술대회 논문집 방전 플라즈마 유기절연재료 초전도 자성체연구회
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    • pp.25-29
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    • 2004
  • Corona on polymer materials causes deterioration by the combined action of the discharge striking the surface and the action of certain chemical compounds that are formed by the discharges. In the design and manufacture of polymer insulators must be sufficiently large to avoid corona discharges, otherwise a shielding or corona ring (grading ring) needs to be installed on the insulator. To conduct this purpose, many researchers have investigated end-fitting of polymer insulator by voltage distribution simulation and electrical test. Grading rings are used to improve the performance of the insulator in multiple ways. They can reduce corona and associated audible noise and radio influence and television interference. The factors determining the uses of a grading ring are line voltage, geometry and dimensions of end fittings, geometry and dimensions of line hardware, and environmental conditions. In this paper, electrical property of polymer insulator with end-fitting design have been investigated by electrical field analysis, various end-fitting design, tracking wheel test, corona inception voltage and extinction voltage. Electrical field analysis is conducted by FEM program and various end-fitting is designed through this result. Designed end-fittings are manufactured and their performance is conducted by electrical performance test.

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구약성서(舊約聖書)에 나타난 히브리인의 복식(服飾) - 두식(頭飾), 신발 및 장신구(裝身具) 중심(中心)으로 - ("A Study on Hebrews Clothing in the Old Testament" - Especially on Hair Styles, Headgears, Footwear and Personal Ornaments -)

  • 박찬부
    • 복식
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    • 제10권
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    • pp.63-80
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    • 1986
  • The Old Testament cotains mention of the history of creation and clothing in ancient Hebrew. This study dealt with Hebrew dress customs especially aimed at the manners of their hair styles, headgears, footwear and personal ornaments. References are Korean Revised Version, English King James Version and Revised Standard Version. There is little mention of hair styles and headgears in the Old Testament. Some sort of turban was worn by priests, and soldiers protected themselves with helmets, but most Israelitish men went bareheaded except on special occasions and often wear simple headbands. It was more common for women to use headwear of some type-turbans, scarves, and veils concealing the face. The veil was the distinctive female wearing apparel. All females, with the exception of maidservants and women in a low condition of life, wore a veil. It was the custom for women to wear a veil entirely covering their head in the public. Through most of the Old Testament periods long and thick hair was admired on men and women alike. The Hebrews were proud to have thick and abundant long hair, and they gave much attention to the care of their hair. The caring of hair was deeply related to their rituals. Nazirites never took a razor to their hair during his vow-days, but instead let it grow long, as an offering to God. Men would not cut their beards, but allow them to grow long. The Israelites' standard footwear was a pair of simple leather sandals. This was one of the items of clothing not highly prized. In a colloquial saying of the time, a pair of shoes signified something of small value, and to be barefoot except in times of mourning or on holy place, was a sign either of extreme poverty or humiliation, as in the case of war prisoners. Because precious stones were not mined in the Palestine-Syria region, Hebrews imported them from foreign country. They were consumer-to a large degree limited by their very modest standard of living-but not producers. Hebrews liked the precious stones and were motivated to acquire and wear jewels. Besides their use for adornment and as gifts, the precious or semiprecious stones were regarded by Jews of property. The Hebrews were not innovators in the field of decorative arts. The prohibition of the Law against making any "graven image" precluded the development of painting, sculpture, and other forms of representational art. Jewish men did not indulge in extravagances of dress, and there was little ornamentation among them. Men wore a signet ring on their right hand or sometimes suspended by a cord or chain around the neck. The necklaces, when worn by a male, also bore any symbol of his authority. Bracelets were extremely popular with both men and women, men usually preferring to wear them on their upper arms. The girdle was a very useful part of a man's clothing. It was used as a waist belt, or used to fasten a man's sword to his body, or served as a pouch in which to keep money and other things. Men often carried a cane or staff, which would be ornamented at the top. Among the women there was more apt to be ornamentation than among the men. Hebrew women liked to deck themselves with jewels, and ornamentation of the bride were specially luxurious and numerous. They wore rings on their fingers or On toes, ankle rings, earrings, nosering, necklace, bracelets. Their shapes were of cresent, waterdrops, scarab, insect, animal or plant. Sometimes those were used as amulets. They were made of ceramics, gold, silver, bronze, iron, and various precious stones which were mostly imported from Egypt and Sinai peninsular. Hebrews were given many religious regulations by Moses Law on their hair, headgears, sandals and ornamentation. Their clothing were deeply related with their customs especially with their religions and rituals. Hebrew religion was of monotheism and of revealed religion. Their religious leaders, the prophets who was inspired by God might need such many religious regulations to lead the idol oriented people to God through them.

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Interaction of Resveratrol and Genistein with Nucleic Acids

  • Usha, Subbiah;Johnson, Irudayam Maria;Malathi, Raghunathan
    • BMB Reports
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    • 제38권2호
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    • pp.198-205
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    • 2005
  • Resveratrol (RES) and genistein (GEN) are the dietary natural products known to possess chemopreventive property and also the ability to repair DNA damage induced by mutagens/carcinogens. It is believed that the therapeutic activity of these compounds could be primarily due to their interaction with nucleic acids but detailed reports are not available. We here explore the interaction of these drugs with nucleic acids considering DNA and RNA as a potential therapeutic target. The interaction of RES and GEN has been analysed in buffered solution with DNA [saline sodium citrate (SSC)] and RNA [tris ethylene diammine tetra acetic acid (TE)] using UV-absorption and Fourier transform infrared (FTIR) spectroscopy. The UV analysis revealed lesser binding affinity with nucleic acids at lower concentration of RES (P/D = 5.00 and 10.00), while at higher drug concentration (P/D = 0.75, 1.00 and 2.50) hyperchromic effect with shift in the ${\lambda}_{max}$ is noted for DNA and RNA. A major RES-nucleic acids complexes was observed through base pairs and phosphate backbone groups with K = $35.782\;M^{-1}$ and K = $34.25\;M^{-1}$ for DNA-RES and RNA-RES complexes respectively. At various concentrations of GEN (P/D = 0.25, 0.50, 0.75, 1.00 and 2.50) hyperchromicity with shift in the ${\lambda}_{max}$ from 260 $\rightarrow$ 263 om and 260 $\rightarrow$ 270 nm is observed for DNA-GEN and RNA-GEN complexes respectively. The binding constant (from UV analysis) for GEN-nucleic acids complexes could not be obtained due to GEN absorbance overlap with that of nucleic acids at 260 nm. Nevertheless a detailed analysis with regard to the interaction of these drugs (RES/GEN) with DNA and RNA could feasibly be understood by FTIR spectroscopy. The NH band of free DNA and RNA which appeared at $3550-3100\;cm^{-1}$ and $3650-2700\;cm^{-1}$ shifted to $3450-2950\;cm^{-1}$ and $3550-3000\;cm^{-1}$ in DNA-RES and RNA-RES complexes respectively. Similarly shifts corresponding to $3650-3100\;cm^{-1}$ and $3420-3000\;cm^{-1}$ have been observed in DNA-GEN and RNA-GEN complexes respectively. The observed reduction in NH band of free nucleic acids upon complexation of these drugs is an indication of the involvement of the hydroxyl (OH) and imino (NH) group during the interaction of the drugs and nucleic acids (DNA/RNA) through H-bonded formation. The interaction of RES and GEN with bases appears in the order of G $\geq$ T > C > A and A > C $\geq$ T > G. Further interaction of these natural compounds with DNA and RNA is also supported by changes in the vibrational frequency (shift/intensity) in symmetrical and asymmetrical stretching of aromatic rings of drugs in the complex spectra. No appreciable shift is observed in the DNA and RNA marker bands, indicating that the B-DNA form and A-family conformation of RNA are not altered during their interaction with RES and GEN.

소규모 개발 사업지의 정밀 임상도(영급) 작성 방안 연구 (Mapping Method for a Detailed Stock Map Plan(Age-Class) for a Small-Scale Site for Development Work)

  • 이수동;김정호
    • 한국환경생태학회지
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    • 제22권4호
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    • pp.396-408
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    • 2008
  • 국립산림과학원에서 발간된 임상도에 따르면 파주시 광탄면에 위치한 본 연구대상지는 활엽수 Ⅳ영급으로 분류되었으나 식생조사 결과 영급판정이 어려운 활엽수 천연림으로 구성되어 정밀 임상도 작성의 필요성이 제기되었다. 이에 정밀 현존식생 조사와 식생구조 및 연륜 분석 자료를 기초로 한 정밀 임상도 작성방안을 제안하고자 하였다. 정밀 현존식생유형 분석결과 22개 유형이었으며 자연림은 신갈나무림, 굴참나무림 등 11개 유형, 인공림은 밤나무림 등 6개 유형으로 구분되었다. 영급 판정을 위해 정밀 현존식생도를 바탕으로 방형구 42개와 89개 표본목의 목편을 채취하여 수령을 측정한 결과, 저지대에 입지한 인공림, 참나무류 소경목 지역은 II영급(29.8%), 나머지 지역은 III영급(57.6%)으로 토지이용이 가능하였고 Ⅳ영급 이상(8.8%)은 경계부의 급경사 능선부에 분포하여 토지이용은 불가능하였다. 이상과 같이 소규모 개발 예정지가 활엽수 자연림으로 판정된 경우 보전과 이용 판정에 있어 정밀 현존식생 조사, 식물군집구조 및 표본목 분석을 통한 정밀 임상도를 작성하여야 할 것이다. 정밀 임상도에는 식생의 자연성, 희소성, 다양성 등을 종합적으로 판단할 수 있는 자료가 포함되어 소규모 부지의 개발적정성 판단에 유용할 것으로 사료된다.

새로운 폴리(티오우레탄)의 합성 및 특성 (Synthesis and Characterization of Novel Polythiourethanes)

  • 김경만;허영태;박인환;이범재
    • 폴리머
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    • 제27권5호
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    • pp.470-476
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    • 2003
  • 고굴절률을 갖는 플라스틱 재료를 얻기 위하여 1,2-에틸렌디설파닐비스(2-머캅토메틸-1-에탄티올) (ESTT)을 1,2-에틸렌디설파닐비스(2-브로모메틸-1-에탄티올) (ESTB)과 티오우레아의 반응과 암모니아 용액으로 가수분해 반응을 해서 높은 수율로 새로이 합성하였고, $^1$H-NMR, $^{13}$C-NMR, FT-IR및 Mass Specooscopy 등에 의해 1.7 ppm에서 -SH, 28.4 ppm에서 -CH$_2$SH, 2540 $cm^{-1}$ /에서 -SH등의 관능기 구조를 확인하였다. 이어서, 폴리티오우레탄 (PTU)들은 디부틸틴 디라울레이트 존재하에서 ESTT와 4,4'-메틸렌비스(페놀이소시아네이트) (MDI), 톨릴렌 2,4-디이소시아네이트 (TDI), 이소포론 디이소시아네이트 (IPDI), m-자일렌디이소시아네이트 (XDI) 및 1,6-디이소시아네이토헥산 (HMDI) 등을 일정한 틀에 넣고 주형중합을 하고, FT-IR로 N=C=O의 존재를 확인하였다. 이어서, PTU 수지들의 열적, 기계적 및 광학적 성질을 살펴보기 위하여 열주사분석 (DSC)과 열중량분석 (TGA), 경도 및 굴절률 측정 등을 행하여, PTU 시편들이 DSC상에서 융점이 없고 XRD상으로 무정형임을 관찰하였다. 또, 110 $^{\circ}C$ 이상의 유리 전이 온도를 갖는 PTU 수지들은 86∼89 범위의 양호한 경도 (Shore D)를 나타냈으며, 방향족 고리를 함유하는 디이소시아네이트와 ESTT를 원료로 했던 PTU수지들의 내열성이 특별히 양호하였다. 무정형 PTU 수지들은 400∼600 m 범위의 UV-vis 광원에 의한 광투과율 들도 양호하게 나타났다. PTU 수지들은 1.60 이상의 굴절률을 보였으며, 황함량이 증가하면 굴절률도 점차 증가하는 것이 관찰되었다.

Micro파(波) 가열(加熱)이 전분질(澱粉質) 식품(食品)에 미치는 영향(影響)에 관(關)한 연구(硏究) -1. Micro파(波) 가열이 감자전분(澱粉) 조성(組成)에 미치는 이화학적(理化學的) 성질(性質)에 관하여- (A Study on the Effect of Microwave Heating on Starch Food -1. The Physico-chemical Property of the Effect of Microwave Heating on Potato Starch and Purified Potato Starch-)

  • 최옥자;고무석
    • 한국식품영양과학회지
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    • 제13권3호
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    • pp.268-274
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    • 1984
  • micro파(波) 가열(加熱)이 일반성분(一般成分) 조성(組成)이 다른 감자전분(澱粉)에 미치는 영향을 실험(實驗)한 결과(結果)는 다음과 같다. 1. 전분(澱粉)의 일반성분(一般成分)은 전분조성(澱粉組成)에 관계없이 micro파(波) 가열(加熱)에 의해 수분(水分)과 조지방(粗脂肪) 함량(含量)이 감소했으며, 회분(灰分)은 약간의 감소 경향을 보였고, 조단백질(粗蛋白質) 함량(含量)은 거의 변화(變化)가 없었다. 2. 감자전분(澱粉)의 X-ray 회절도(回折圖)는 micro파(波) 가열(加熱)에 의해 결정성을 나타내는 환(環)들이 변화(變化)되기 시작하였는데, 면간격(面間隔)이 큰 1환(環)에서 뚜렷이 나타났고 전분조성(澱粉組成)에 의한 차는 없었다. 3. 주사형전자현미경(走査型電子顯微鏡)으로 관찰(觀察)한 전분입자(澱粉粒子)는 micro파(波) 가열량(加熱量)이 증가됨에 따라 파열되었는데 P.P.S.가 P.S.에 비하여 더 빨리 나타났다. 4. 전분(澱粉)의 호화온도(糊化溫度)는 micro파(波) 가열량(加熱量)이 증가할수록 낮아졌고 팽윤도(膨潤度) 및 용해도(溶解度)는 증가 하였는데, P.P.S.는 P.S.에 비(比)하여 호화온도(糊化溫度)는 더 낮았고 팽윤도(膨潤度) 및 용해도(溶解度)는 더 높았다.

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DGEBA/방향족 아민(DDM, DDS) 경화제의 벤젠링 사이의 관능기 변화가 물성 변화에 미치는 영향에 대한 연구 (Chemo-Mechanical Analysis of Bifunctional Linear DGEBA/Linear Amine (DDM, DDS) Resin Casting Systems)

  • 명인호;정인재;이재락
    • Composites Research
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    • 제12권4호
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    • pp.71-78
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    • 1999
  • 방향족 아민 경화제의 벤젠링 사이의 관능기 변화가 반응특성, 기계적특성 및 열적특성에 미치는 영향을 고찰하기 위하여 양쪽 말단기에 에폭시기를 가지는 대표적 범용 에폭시수지인 DGEBA (diglycidylether of bisphenolA)와 방향족아민 경화제 diaminodiphenyl methane (DDM), diaminodiphenyl sulphone(DDS) 각각을 1:1의 당량비로 혼합하여 동일한 조건으로 경화하였다. 반응특성, 열 안정성, 에폭사이드기의 전환율, shrinkage(%), 유리전이온도와 선팽창계수, 기계적특성 그리고 굴곡 파단특성을 알아보기 위하여 각각 DSC 분석, TGA 분석, FT-IR 분석, 밀도측정, TMA 분석, 인장시험과 3점 굴곡시험, 광학현미경 시험을 행하였다. 그 결과, 에폭시수지 경화물의 분석, 밀도측정, TMA 분석, 인장시험과 3점 굴곡시험, 광학현미경 시험을 행하였다. 그 결과, 에폭시수지 경화물의 특성은 경화제의 벤젠링 사이의 관능기 구조에 따라 매우 큰 영향을 받았다. 즉, 벤젠링 사이에 길이가 길고 bulky한 술폰기를 포함한 DDS는 epoxiderl의 전환율, shrinkage(%), 유리전이온도, 인장탄성율, 인장강도, 굴곡탄성율 및 굴곡강도의 값이 길이가 짧고 compact한 메틸기를 가지는 DDM 경화물계 보다 높게 나타났지만, 최대발열온도, 열안정성, 선팽창계수의 값은 낮게 나타냈다. 이것은 술폰기의 강한 전기음성도와 메틸기의 전기 양성적인 repulsive한 성질의 차이와 epoxide group의 전환율의 영향인 것으로 판단된다. 굴곡 파단면의 관찰 결과는 DDM경화물계의 feather like structure의 각개 grain의 크기가 DDS 경화물계 보다 작은 것을 확연하게 보여준다.gG1 항체 합성은 spleen B cell과는 달리 TGF-$\beta$3에 의해 증가하였다. 본 실험의 결과는 전반적으로 TGF-$\beta$3가 TGF-$\beta$1과 비슷한 정도로 마우스 B cell의 항체합성에 영향을 미침을 보여준다. 그렇지만, 생체 내에서TGF-$\beta$3의 발현조절이 TGF-$\beta$1과 다를 것으로 예상됨으로 과연 TGF-$\beta$3가 B cell 분화에서 중요한 조절인자로 작용할지는 좀 더 연구되어야 할 것이다.적을 볼 때 적극적으로 수술에 임하는 것이 바람직하다고 사료된다.나타나 이의 규명을 위해서는 향후 p53 단백의 유전자 변이와 두 단백의 발현과 환자의 생존율과의 상관관계에 대한 연 구가 요할 것으로 사료된다.을 줄이기 위한 대책이 도움이 될 것으로 사료된다.4.00$\pm$0.14, 2.50$\pm$ 0.31, 4.02$\pm$0.70으로 기준(1.84$\pm$0.21)에 비하여 IP군과 10 mM 칼슘 전처치군에서 유의하게 증가하였다 (p<0.05). 그러나 허혈대조군에서는 두 분획 모두 기준선과 비교하여 큰 차이가 없었다. 결론: 이상으로 적출 관류 토끼심장에서 장시간 동안의 허혈전 높은 농도의 칼슘으로 전처치하면 허혈후 재관류시 심근기능의 회 복증가는 기대하기 어려우나 IP와 유사한 심근괴사 범위 감소효과가 있으며 이러한 효과는 아마도 칼슘의 매개에 따라 PKC활성화가 일어남으로써 나타나는 것으로 생각된다. 점을 함께 고려하면 그룹 B에서의 더 큰 증폭 효과가 광배근의 활성도 및 수축력의 차이로부터 기인한다고 평가할

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