• 제목/요약/키워드: Development Team Size

검색결과 221건 처리시간 0.022초

전자빔 증착을 위한 소결체 지르코니아의 열충격 저항성 연구 (A Study on the Thermal Shock Resistance of Sintered Zirconia for Electron Beam Deposition)

  • 오윤석;한윤수;채정민;김성원;이성민;김형태;안종기;김태형;김동훈
    • 한국추진공학회지
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    • 제19권3호
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    • pp.83-88
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    • 2015
  • 열차폐 코팅(Thermal Barrier Coating) 기술의 하나로 연구되는 전자빔(EB, Electron Beam) 증착에 사용되는 코팅재료는 증착 공정 중에 고출력의 전자빔이 조사되기 때문에, 균일코팅을 위해서는 증착 중 코팅재료의 형상유지 및 안정한 융탕 형성이 필요하며, 이를 위해 적절한 밀도와 미세구조를 갖춘 잉곳(Ingot) 형태의 코팅소스가 요구된다. 본 연구에서는 8 wt%의 이트리아($Y_2O_3$)가 안정화제로 첨가된 지르코니아(8YSZ) 조성을 활용하여, 고출력 전자빔 조사환경에 사용가능한 잉곳제조를 위해 최적의 원료분말 조건을 확보하고자 하였다. 제조된 잉곳시료들에 대한 전자빔 조사 시, 수십 마이크론과 수십 나노 크기의 입자들로 구성된 혼합형 분말로 제조된 잉곳의 경우, 나노크기의 분말만으로 제조된 경우보다 향상된 열충격 저항성을 보였다.

내염성 국화 형질전환 계통 육성 및 저항성 검정과 세포특성 변화 (Development of salt-tolerant transgenic chrysanthemum (Dendranthema grandiflorum) lines and bio-assay with a change of cell specificity)

  • 강찬호;윤성중;한범수;이공준;최규환;박종숙;신용규
    • Journal of Plant Biotechnology
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    • 제38권1호
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    • pp.1-8
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    • 2011
  • 최근 시설재배의 증가나 새만금 간척지의 개발 등 염류 농도가 높은 토양에서의 작물 재배에 대한 수요가 점차적으로 증가하고 있는 상황에서 고염환경 하에서 세포내로 주입된 염 분자를 제한된 구역으로 격리하여 염류내성을 주도록 하는 anti-porter 유전자 TANHX, HVNHX를 우리나라 주요 화훼작물이며 수출유망 작물인 국화로 도입하는 분자육종이 백마 등 5품종에 대하여 이루어졌다. 선발 마커를 이용한 배지선발 과정을 통하여 선발된 기내 식물체 390개체를 대상으로 토양 순화를 거쳐 284계통의 국화 형질전환체가 획득되었으며, 얻어진 식물체 중 임의로 40계통을 선발하고 PCR을 거쳐 진성 여부를 확인한 결과 30계통에서 target band가 검출되어 75%의 배지 발 성공률을 나타내었다. PCR 분석 선발 계통을 포함하여 토양 순화된 284계통을 대상으로 직접적으로 NaCl 0.2 ~ 1.2% (300 mM) 범위로 내염성 생물검정을 실시한 결과 NaCl 0.8% (200 mM) 농도에서도 생존 및 생장이 가능한 15계통이 선발되었으며 이중 7계통은 NaCl 1.2%(300 mM) 내에서도 생존이 가능하였다. 내염성 특성형질 도입을 위하여 anti-porter 유전자 HVNHX가 도입되어 선발된 형질전환 계통의 스트레스 저항성 정도 및 세포 형태적 특성변화가 관찰되었다. 선발된 계통은 NaCl 1.2% (300 mM) 처리 생존가능 7계통을 포함하여 NaCl 0.8% (200 mM) 관수 처리 하에서 생존 및 생장이 가능한 15계통이었다. 세포형태 특성은 전자현미경 (SEM)을 이용하여 형질전환체 및 비 형질전환체의 공변세포를 염 처리 후 관찰함으로서 이루어졌는데 형질전환체, 비형질전환체 모두 무처리에 비해 NaCl 처리한 식물체의 공변세포의 두께가 두꺼워지고 조직 치밀도가 증가하였으며 형질전환체의 경우 비 형질전환체에 비해 두꺼워지는 정도나 조직의 치밀도 증가 정도가 높아 염에 대한 내성이 강화되었음을 알 수 있었고 염 처리 후 세포의 생존정도 비교를 통한 내염 스트레스에 대한 저항성 정도를 측정하고자 TTC 검정을 실시한 결과 강 내염성 계통의 TTC 수치가 높게 나왔으며 NaCl 처리 농도가 높아질수록 TTC 수치가 낮아지는 경향이었으나 강 내염성 7계통은 1.2% NaCl 처리에서도 0.206 ~ 0.331로 비형질전환체의 0.046 중내염성 계통의 0.114 ~ 0.193에 비해 높은 세포생존 비율을 나타내었다. 또한 식물이 스트레스에 대항하기 위하여 분비하는 아미노산인 Proline의 함량을 계통별로 측정한 결과 강 내염성 형질전환 계통이 높게 나왔으며 NaCl 처리 농도가 높아질수록 증가하는 경향을 나타내어 강 내염성 7계통은 1.2% NaCl 처리에서 2.255 ~ 2.638 mg/kg로 중 내염성 형질전환 계통의 1.496 ~ 2.125에 비해 높게 형성되었다.

화생방 테러의 양상과 예방대책 (A preparation and Strategy against Chemical and Biological Terrorism)

  • 김경회
    • 시큐리티연구
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    • 제5호
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    • pp.19-40
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    • 2002
  • For front, aspect of terror may have to prepare indeed even chemical terror or rocket and small size missile and radioactivity terror because is predicted to become various. Furthermore, when see motion of every countries about nuclear engineerses' bringing round and illicit sale of plutonium, our country may have to prepare in terrorism which is expected thus. So that can finish international event successfully because the United States of America supports great manpower and budget since New York's World Trade Center terror and when see that is considering terror prevention countermeasure, we operate temporarily bursting tube state complete charge team such as terror by each field specialist such as a concern interested including special CBR complete charge moving team among 2002 World Cups soccer game period ahead of international event, must consider safety countermeasure. Specially, biology weapon of chemical weapon and cholera etc. 13 kinds of 5000ton that North Korea plans CBR terror society confusion that North Korea that to terror support nation as well as nuclear weapons development suspicion is defending South Korea communization strategy as real condition that is amplified as well as is saving production brand gets imprinted uses CBR terror at normal times, when see that is planing powerlessness communization unity using CBR weapon at time of war, must operate until bias 2002 World Cups international event finishes cooperation safety countermeasure utensil safely under closer talk between the South Korea ${\cdot}$ Japan ${\cdot}$ North Korea. As for us which must serve 2002 World Cup successfully to accomplish perfectly preparedness of CBR terror firstly, all inhabitants knows well CBR protection trick, and secondly, CBR existing formation that solidify realignment CBR complete charge moving team which of course is consisted of CBR specialist compose and keeping immediate going out attitude operating, by third, that expand CBR individual protection equipment and CBR evacuation equipment and establish individual and group protection attitude naturally, supplement as there is main room that actualize CBR pollution patient's slogan countermeasure by fourth, and develop standard model for CBR terror provision by fifthBecause constructing infra of CBR safety establishing CBR preparedness that utilize it, must minimize damage and contribute inhabitants' life and property protection.

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AQS: An Analytical Query System for Multi-Location Rice Evaluation Data

  • 프란코 나자레노;정승현;강유진;이경희;조완섭
    • 한국산업정보학회논문지
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    • 제15권2호
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    • pp.59-67
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    • 2010
  • Rice varietal information exchange is vital for agricultural experiments and trials. With the growing size of rice data gathered around the world, and numerous research and development achievements, the effective collection and convenient ways of data dissemination is an important aspect to be dealt with. The collection of this data is continuously worked out through various international cooperation and network programs. The problem in acquiring this information anytime anywhere is the new challenge faced by rice breeders, scientist and crop information specialists, in order to perform rapid analysis and obtain significant results in rice research, thus alleviating rice production. To address these constraints, we propose an Online Analytical Query System, a web query application to provide breeders and rice scientist around the world a fast web search engine for rice varieties, giving the users the freedom to choose from which trial it has been used, trait observation parameters as well as geographical or weather conditions, and location specifications. The application uses data warehouse techniques and OLAP for summarization of agricultural trials conducted, and statistical analysis in deriving outstanding varieties used in these trials, consolidated in an Model-View-Controller Web framework.

고장력 강판 부분용입 맞대기 용접부의 피로균열진전수명 평가 (Fatigue Crack Propagation Life of Partially Penetrated Butt Welds in High Strength Steel)

  • 한승호;신병천;이웅;최전호
    • Journal of Welding and Joining
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    • 제21권1호
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    • pp.72-79
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    • 2003
  • Fatigue behaviour of partially penetrated butt-welded joints in high strength steel plates, in which crack-like structural defect, i.e. lack of penetration(LOP), is inevitably introduced during welding processes, was investigated. Fatigue lives of two types of welded joints, namely X-grooved and K-grooved joints, were experimentally determined first. Observed fatigue crack propagation behaviours of the partially penetrated butt-welds were interpreted through considering 3-dimensional semi-elliptical crack shape in front of the LOP. Based on such interpretation, a fracture mechanical method to estimate stress intensity factors at the crack tip was proposed. Since the fatigue lift of the partially penetrated butt-welds was strongly influenced by the ratio of size of the LOP to thickness, D/t, the D/t was used as a main parameter to calculate the fatigue lift by using the proposed method. Comparison of the fatigue lift obtained experimentally and analytically agreed well with each other. Hence it is suggested that the method used in this work to predict fatigue lift of the partially penetrated butt-welds can be applied to real cases with improved lift-prediction capability.

Advances in blue and white Light Emitting Diode using AlInGaN mesa structure and Display Module

  • Park, Book-Sung;Kim, Sung-Woon;Jung, In-Sung;Lee, Seon-Gu;Son, Sung-Il;Lee, Jee-Myun;Kim, Eun-Tae;Kim, Chul-Ju
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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    • pp.347-348
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    • 2008
  • The main goal of this work is advances in 1.0mm $\times$ 0.5mm light emitting diode using AlInGaN cell structure and display module. In the first place, we proposed $200{\mu}m{\times}200{\mu}m$ cell structure using AlInGaN. Secondly, we describe new type 1.0mm $\times$ 0.5mm blue and white LED fabrication procedure and results of an examination include mobile application.

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도시 균형발전을 고려한 지속가능한 도심활성화 방안 연구 (시흥시를 중심으로) (A Study on Sustainable Downtown Activation Plan Considering Balanced Development of City (Focused on Siheung City in Korea))

  • 박훈;양성민
    • 한국산학기술학회논문지
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    • 제12권10호
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    • pp.4648-4659
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    • 2011
  • 우리나라는 경제의 고도성장으로 급격한 도시화를 맞이하였으며, 경제적 혜택을 위한 이촌향도로 도시규모가 팽창하면서 전국토의 불균형 발전을 초래하게 되었다. 또한 이는 전국적인 현상에서 국지적 시단위의 개발에까지 다양한 양상으로 나타나고 있으며, 특히 수도권지역에 위치하는 도시에서 사회적 문제로 까지 되는 경향이 초래되고 있다. 이에 대한 해소방안으로 도시균형발전 측면에서의 지속가능성에 대한 이론적 고찰과 함께 시흥시의 분석을 통해 방안을 제시하였으며, 결론은 다음과 같다. 첫째, 지속가능성을 전제로 한 종합적 접근이 요구되며, 사회 문화 및 경제적 측면으로 확대하여 도시의 균형발전을 유도할 필요성이 있다. 둘째, 신개발과 함께 원도심에 대한 통합적 관리 정책이 요구된다. 이는 다양한 사회적, 물리적 접근과 병행해야 한다. 셋째, 도시공간구조의 연계와 평면적 도시확산에 대한 고려를 통한 도시계획적 측면에서의 접근방안 모색이 필요하다. 넷째, 도시균형발전을 도모하기 위해서 이해 관계자 간의 조정과 함께 특히, 지역주민, 민간사업자, 그리고 지역사회의 비영리 시민단체 등 다양한 그룹의 참여를 통한 도시 불균형 해결방안 모색이 요구된다. 그리고 이와 함께 위와 같은 환경이 조성될 수 있도록 행정관청의 지속적인 지원이 수반되어야 하겠다.

분말법과 주조법으로 제조한 coated conductor용 Ni 기판 개발 (Fabrication of textured Ni substrates for coated conductor prepared by powder metallurgy and plasma arc melting method)

  • 임준형;김정호;김규태;장석헌;주진호;나완수;홍계원;지봉기;김찬중
    • Progress in Superconductivity
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    • 제5권1호
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    • pp.70-74
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    • 2003
  • We fabricated cube textured Ni substrate for YBCO coated conductor and evaluated the effects of processing parameters on microstructural evolution and texture formation. Ni-rods as an initial specimen were prepared by two different methods, i.e., powder metallurgy(PM) and plasma arc melting(PAM). Subsequently, the rods were cold rolled to 100 $\mu\textrm{m}$ thick substrate and annealed at temperatures of $700∼1200^{\circ}C$. The texture of the substrate was characterized by pole-figure. It was observed that the texture of substrate made by P/M did not significantly varied with annealing temperature of 600∼$l100^{\circ}C$ and the full-width at half-maximums (FWHM) of both in-plane and out-of-plane were 9$^{\circ}$$10^{\circ}$. On the other hand, the texture of substrate made by PAM was more dependent on the annealing temperature and the corresponding values were $9^{\circ}$$13^{\circ}$ at the temperature range. In addition, recrystallization twin texture, (221)<221>, was formed as the temperature increased further. OM profiles showed that the grain size of substrate made by P/M was smaller than that made by PAM and this difference was correlated to the microstructure of initial specimens.

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한국인의 성별, 연령별, 지역별 콜린 섭취 추정량 (Estimation of Dietary Choline Intake of Korean by Gender, Age and Region)

  • 정한옥;김초일;이행신;정영진
    • Journal of Nutrition and Health
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    • 제38권4호
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    • pp.320-326
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    • 2005
  • This study was conducted to estimate dietary choline intake of Koreans according to gender, age and region by using the data on per capita food intake in 1998 and 2001 and the data on choline contents of foods customarily eaten by Koreans. Sixty-four and 97 kinds of food items were used for the estimation of choline intake in 1998 and 2001, respectively. And these corresponded to approximately $90\%$ of the total amount of food intake and energy intake. Based on these food items and choline content, per capita choline intake of Koreans was estimated to be 623.0 mg and 602.4 mg in 1998 and 2001 respectively , 687.2 mg and 659.1 mg in 1998 and 2001 for male, 560.2 mg and 551.0 mg in 1998 and 2001 for female. While the number of foods considered in estimation was higher in 2001 than 1998, choline intake was lower in 2001. The estimated per capita choline intake of male population was higher than that of female population by 108-127 mg, possibly due to the difference in total amount of food intake. The age group with the highest choline intake was different between 2 time points. Although adolescents of 13- 19 years showed the highest intake (712.0 mg) in 1998, mid-aged adults of 30-49 years showed the highest choline intake (662.2 mg) followed by adolescents (645.7 mg) in 2001. In regional comparison, choline intake of the rural population (588.7 mg and 588.3 mg in 1998 and 2001 respectively) was lower than that of population in small to medium-size cities (625.1 mg and 603.9 mg) or in metropolitan cities (637.7 mg and 602.8 mg). This result revealed that per capita choline intake of the Korean population falls within the adequate range with some differences by age, sex and residing area.

Pulse-reverse도금을 이용한 다층 PCB 빌드업 기판용 범프 생성특성 (Characteristics of Plated Bump on Multi-layer Build up PCB by Pulse-reverse Electroplating)

  • 서민혜;공만식;홍현선;선지완;공기오;강계명
    • 한국재료학회지
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    • 제19권3호
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    • pp.151-155
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    • 2009
  • Micro-scale copper bumps for build-up PCB were electroplated using a pulse-reverse method. The effects of the current density, pulse-reverse ratio and brightener concentration of the electroplating process were investigated and optimized for suitable performance. The electroplated micro-bumps were characterized using various analytical tools, including an optical microscope, a scanning electron microscope and an atomic force microscope. Surface analysis results showed that the electroplating uniformity was viable in a current density range of 1.4-3.0 A/$dm^2$ at a pulse-reverse ratio of 1. To investigate the brightener concentration on the electroplating properties, the current density value was fixed at 3.0 A/$dm^2$ as a dense microstructure was achieved at this current density. The brightener concentration was varied from 0.05 to 0.3 ml/L to study the effect of the concentration. The optimum concentration for micro-bump electroplating was found to be 0.05 ml/L based on the examination of the electroplating properties of the bump shape, roughness and grain size.