• 제목/요약/키워드: fundamental unit

검색결과 434건 처리시간 0.025초

관개용수 수질과 벼 수확량, 미질과의 상관관계 규명 (Correlations of Irrigation Water Quality to Yield and Quality of Rice Grain)

  • 최선화;최호진;장정렬;이승헌;오종민
    • 한국물환경학회지
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    • 제21권2호
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    • pp.169-175
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    • 2005
  • This study was carried out to investigate the effects of irrigation water pollution on the yield and grain quality of rice. It acquires fundamental data to set up water quality standards for irrigation and produce agricultural safety products. The correlations of BOD, T-N, T-P, pH, ECw of the irrigation water with yield, grain appearance quality, and the protein content were evaluated. The field and pot experiments were conducted by using Japonica of Oryza sativa L. during 2 years. BOD concentration in irrigation water effects strongly on grain appearance quality and yield of rice. T-N in irrigation water has strong effect on the yield, appearance, and quality of rice. T-P concentration in irrigation water have not any correlation with yield and quality of rice. pH showed strongly negative correlation with maturity ratio(MTR), 1000 grain weight(TGW), and yield of rice(YLD) as r=-0.803~-0.828(p<0.001) and have no effect on the appearance quality of rice. $EC_w$ indicating salt content showed strongly negative correlation with MTR, TGW, number of grains per panicles(NGP), and number of panicles per unit area(NPM) as r=-0.759~-0.798, and with YLD as -0.753.

Quantum Hall Effect of CVD Graphene

  • Kim, Young-Soo;Park, Su-Beom;Bae, Su-Kang;Choi, Kyoung-Jun;Park, Myung-Jin;Son, Su-Yeon;Lee, Bo-Ra;Kim, Dong-Sung;Hong, Byung-Hee
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2011년도 제40회 동계학술대회 초록집
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    • pp.454-454
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    • 2011
  • Graphene shows unusual electronic properties, such as carrier mobility as high as 10,000 $cm^2$/Vs at room temperature and quantum electronic transport, due to its electronic structure. Carrier mobility of graphene is ten times higher than that of Silicon device. On the one hand, quantum mechanical studies have continued on graphene. One of them is quantum Hall effect which is observed in graphene when high magnetic field is applied under low temperature. This is why two dimension electron gases can be formed on Graphene surface. Moreover, quantum Hall effect can be observed in room temperature under high magnetic field and shows fractional quantization values. Quantum Hall effect is important because quantized Hall resistances always have fundamental value of h/$e^2$ ~ 25,812 Ohm and it can confirm the quantum mechanical behaviors. The value of the quantized Hall resistance is extremely stable and reproducible. Therefore, it can be used for SI unit. We study to measure quantum Hall effect in CVD graphene. Graphene devices are made by using conventional E-beam lithography and RIE. We measure quantum Hall effect under high magnetic field at low temperature by using He4 gas closed loop cryostat.

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남부지방에 있어서 수도수량구성요소 및 수량해석II. 질소시비량에 따른 주요형질 및 수량의 변이 (Analytical studies on the Rice Yield Component and Yield in South Region of Korea. II. Variation in the rice yield component and yield under the different nitrogen fertilizing levels)

  • 김용재;김규진
    • 한국작물학회지
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    • 제29권3호
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    • pp.218-226
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    • 1984
  • 남부 답다모작지대에 있어서 수도적정시비량을 구명하기 위하여 질소시비량을 10a당 10, 15, 20, 25kg의 4수준, 이앙기를 5월 20일, 6월 5일, 6월 20일, 7월 5일의 4시기로하여 수량구성요소및 수량의 변이를 검토하여 다음과 같은 결과를 얻었다. 1. 난지 도작에 있어서 질소의 적정시비량은 서광벼는 20kg/10a, 동진벼는 15kg/10a 수준이었다. 2. 질소의 적정시비량에서 단위면적당 수수와 등숙률 사이에는 부의 유의 상관관계(서광벼 r =-0.6023* 동진벼 r =-0.8581**)가 인정되었다. 3. 시비수준에 따른 1,2차 지경 및 영화의 퇴화율은 서광벼는 질소 25kg/10a 에서, 동진벼는 질소 20kg/10a 이상의 수준에서 컸다. 4. 등숙비율에 있어서 서광벼는 질소증비에 따른 변이가 크지 않았으나 동진벼는 증비에 따른 급격한 등숙비율의 저하 경향을 보여 수량감소의 주요인이 되었다.

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나노 기술의 중요성과 생체 활성 유기 나노 입자의 제조법 (Significance of Nanotechnology and Preparation Methods of Bioactive Organic Nanoparticle)

  • 유지연;최지연;김기현;이종찬;이종휘
    • Journal of Dairy Science and Biotechnology
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    • 제23권1호
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    • pp.9-17
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    • 2005
  • Nanotechnology has penetrated into the various branches of research and development and it is particularly of benefit to the particle size engineering. It has been widely known that the particle size of an active pharmaceutical ingredient (API) is critical in determining the bioavailability and processability of pharmaceutical formulation. However, the window of appropriate particle size has been limited mainly due to related processing difficulties. The windows have been widened by the recent development of nanotechnologies, resulting in diversified drug delivery systems. The impact of this development is far more fundamental than what can be expected from conventional particle size engineering. It is the case that the preparation and use of nanoparticles will soon be a common task in the particle engineering step of pharmaceutical unit operations. In this chapter, the basic principles of variouspreparation techniques will be discussed in detail. Regardless of processing details, the preparation methods of pharmaceutical nanoparticles mainly concern how to deal with the extra energy related with particle size. Depending on the ways of treating the e103 energy, preparation methods can be classified into two major classes, i.e.. thermodynamic and kinetic approaches. The recent progresses have shown the possibilities of much more complex combinations of different approaches and the use of new types of energy and nanostructures.

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비전공자를 위한 알고리즘씽킹 기반 소프트웨어 기초교육 설계 (Design of Algorithm Thinking-Based Software Basic Education for Nonmajors)

  • 박소현
    • 산경연구논집
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    • 제10권11호
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    • pp.71-80
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    • 2019
  • Purpose: The purpose of this study is to design the curriculum of Basic College Software Programming to develop creative and logical-thinking. This course is guided by algorithmic thinking and logical thinking that can be solved by computing for problem-solving, and it helps to develop by software through basic programming education. Through the stage of problem analysis, abstraction, algorithm, data structure, and algorithm implementation, the curriculum is designed to help learners experience algorithm problem-solving in various areas to develop diffusion thinking. For Learners aim to achieve the balanced development of divergent and convergent-thinking needed in their creative problem-solving skills. Research design, data and methodology: This study is to design a basic software education for improving algorithm-thinking for non-major. The curriculum designed in this paper is necessary to non-majors students who have completed the 'Creative Thinking and Coding Course' Design Thinking based are targeted. For this, contents were extracted through advanced research analysis at home and abroad, and experts in computer education, computer engineering, SW education, and education were surveyed in the form of quasi-openness. Results: In this study, based on ADD Thinking's algorithm thinking, we divided the unit college majors into five groups so that students of each major could accomplish the goal of "the ability to internalize their own ideas into computing," and extracted and designed different content areas, content elements and sub-components from each group. Through three expert surveys, we established a strategy for characterization by demand analysis and major/textbook category and verified the appropriateness of the design direction to ensure that the subjects and contents of the curriculum are appropriate for each family in order to improve algorithm-thinking. Conclusions: This study helps develop software by enhancing the ability of students who practice various subjects and exercises to explore creative expressions in various areas, such as 'how to think like a computer' that can implement and execute their ideas in computing. And it helps increase the ability to think logical and algorithmic computing based on creative solutions, improving problem-solving ability based on computing thinking and fundamental understanding of computer coding and development of logical thinking ability through programming.

대학기숙사 교육기능공간의 매개변수를 통한 인과분석 (Causal Analysis of Education Function Space Parameters of University Dormitory)

  • 박행자;박성진;노영란
    • 한국주거학회논문집
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    • 제21권4호
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    • pp.23-31
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    • 2010
  • This study aims to examine the educational function space of university dormitories at local universities with corridor centered structure in Honam area regions based on direct and indirect parameters on the whole satisfaction of users in residential environment factors and personal characteristics. First, according to relations among parameters, educational and cultural activities of four major activities within the dormitory had indirect influences on social activities, eating and sleeping activities had no direct influence on other activities. And social activity had direct influence on the general satisfaction as an important parameter and educational and cultural activities had indirect influence on the whole satisfaction through social activities. Detailed results show that, in the first educational activities directly affecting the lighting and air conditioning facilities (0.22), safety (0.326), Territoriality (0.327), the space density (-0.167), directions (-0.166) and yeohyang having personal characteristics and the safety of the second cultural activities (0.183), Territoriality (0.361), Aesthetics (-0.13) and the personal characteristics Sex (-0.179), the direct effect, third, and erosion has a direct impact on activity The flexibility of the space factor (-0.128) and Territoriality (0.38) and the personal characteristics grade (0.172), respectively. Fourth in social activities directly affecting the pathfinding (-0.104), and parameter, education (0.388) and cultural activities (0.445), and some of the factors affecting the indirect lighting and air conditioning facilities, safety, and Territoriality, the space density, directions, grade, they could influence through educational activities to be analyzed. That is, territoriality in educational function space is the important factor that users react very sensitively in educational, eating and sleeping activities and educational function space must secure area and division considering personal and public use as the space accommodating activity which is lacking in unit residential space. Accordingly, the safety of educational function space in university dormitory is considered as the fundamental safety matter on the fire prevention, hygiene and cleanness for users in the satisfaction of educational and cultural activities.

Electrical Properties of the Epoxy Nano-composites according to Additive

  • Shin, Jong-Yeol;Park, Hee-Doo;Choi, Kwang-Jin;Lee, Kang-Won;Lee, Jong-Yong;Hong, Jin-Woong
    • Transactions on Electrical and Electronic Materials
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    • 제10권3호
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    • pp.97-101
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    • 2009
  • The use of a filler material in epoxy composite materials is an essential condition for reducing the unit cost of production and reinforcing mechanical strength. However, the dielectric strength of insulators decreases rapidly due to interactions between the epoxy resin and filler particles. In contrast to existing composite materials, nano-composite materials have superior dielectric strength, mechanical strength, and enduring chemical properties due to an increase in the bond strength of the polymer and nano material, It is reported that nano-fillers provide new characteristics different from the properties of the polymer material. This study is to improve the insulation capability of epoxy resins used in the insulation of a power transformer apparatus and many electronic devices mold. To accomplish this, the additional amount of nano-$SiO_2$ to epoxy resin was changed and the epoxy/$SiO_2$ nano composite materials were made, and the fundamental electrical properties were investigated using a physical properties and an analysis breakdown test. Using allowable breakdown probability, the optimum breakdown strength for designing an electrical apparatus was determined. The results found that the electrical characteristics of the nano-$SiO_2$ content specimens were superior to the virgin specimens. The 0.4 wt% specimens showed the highest electrical properties among the specimens examined with an allowable breakdown probability of 20 %, which indicates stable breakdown strength in insulating machinery design.

Flat Dilatometer 현장시험을 통한 점토 지반의 공학적 성질 추정 (Evaluation of Engineering Properties of Clays Through Flat Dilatometer Tests)

  • 이승래;김윤태;김준석
    • 한국지반공학회지:지반
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    • 제8권3호
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    • pp.23-36
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    • 1992
  • Flat DMT는 널리 사용되어지고 있는 현장시험기구로서 간단하고, 경제적이면서도 다양한 지반의 응력-변형-강도특성을 추정할 수 있으나, 이들 현장시험의 결과들은 지역적 특성에 의존하는 경향이 있기 때문에 기준값과 비교하여 많은 연구와 검증을 필요로 한다. 본 연구에서는 기존의 제안된 상관관계식의 우리나라 점토지반에 대한 적용성을 검토하기 위하여 FV 및 CPT의 현장시험을 실시하고, thin-walled tube sampler로 채취된 시료에 대한 비압밀비배수(UU) 실험. oedometer 실험 및 다른 기본적인 물성실험을 수행하여 DMT의 결과들 쏙 비교하였다. 세 장소의 점토지반에서 구한 DMT 결과들로부터 흙의 종류, 단위중량, 정지토 압계수, 과압밀비, 비배수 전단강도 및 변형계수를 추정하였으며 다른 시험결과들과 비교분석하여 우리나라 점토 지반에 대한 적용성을 검토하였다.

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건설시뮬레이션 사이클론 기법을 활용한 시스템 철골계단 공법의 현장적용성 평가 (Construction Performance Evaluation of Steel Staircase Systems based on Construction Simulation CYCLONE Techniques)

  • 이정훈;이경석;김현미;김영석;한승우
    • 한국건축시공학회지
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    • 제10권6호
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    • pp.19-26
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    • 2010
  • 건설 신기술은 현장적용에 대한 불확실성, 기술적 우위의 확신결여 등으로 활성화가 어렵고 신기술 활용실적은 미흡하다. 따라서 건설신기술 현장 적용에 따른 문제를 해결하기 위해 신기술 예측자료가 필요하며, 성능평가 모델이 요구된다. 본 연구의 목적은 의사결정도구로서 건설시뮬레이션을 활용한 신기술의 현장 적용시 예측되는 생산성과 비용을 평가할 수 있는 방안을 도출하는 것이다. 이를 위하여 시스템 철골계단 공법을 선정하였다. 본 공법이 실제 적용 중인 현장에서의 데이터 수집을 기반으로 건설시뮬레이션을 적용하였으며, 이에 본 계단 공법의 1개층 1개소 설치에서부터 6개소 설치 시의 다양한 사례에 대한 시간당 생산성 및 단위비용을 예측하였다. 위의 과정을 통하여 건설시뮬레이션 기법은 현장데이터가 부족한 건설신기술의 현장적용성 평가를 위한 적용의 가능성을 제시하고 있음을 알 수 있다.

Hall 센서를 이용한 엘리베이터 와이어 로프의 비파괴 검출시스템의 개발 (Development of Nondestructive Detecting System for Elevator Wire Ropes using Hall-effect Sensors)

  • 김성덕
    • 센서학회지
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    • 제10권1호
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    • pp.33-41
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    • 2001
  • 와이어 로프는 무거운 중량을 안전하게 운반하거나 기계적인 에너지를 빠르게 전송하는 곳과 같은 산업응용 분야에 광범위하게 사용되어 왔다. 특히, 운전 중 엘리베이터의 와이어 로프가 파손되면 큰 재산 상 손실과 주변 인명의 심각한 상해를 초래할 수 있다. 따라서, 와이어 로프의 정기적인 검사는 매우 중요하다. 와이어 로프의 고장 검출은 로프의 구조, 특성, 결함 특성, 검출방법과 신호처리 방법에 대한 기본적인 이해가 요구된다. 이 연구에서는 엘리베이터에 노화된 와이어 로프에 대한 마모, 단선, 부식과 형붕괴와 같은 결함을 검출하기 위하여, Hall 센서를 결합한 새로운 결함 검출시스템의 개발에 대하여 다룬다. 휴대용 계측기로서 검출기를 사용하기 위하여, Hall 센서를 가진 센싱 부분과 아날로그 신호처리 및 프로그램의 제작에 대한 몇 가지 특성들이 서술되었다. 제작된 검출시스템에 대한 실험과 실장시험 결과 역시 제시되었다. 그 결과, 검출시스템은 사용 중인 노화된 와이어 로프의 결함을 검출하는데 양호한 효율성을 갖는다는 것을 확인하였다.

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