• 제목/요약/키워드: national characteristics

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국가 융합 R&D 특성 분석에 관한 연구: 텍스트분석을 중심으로 (Feature Analyze and Research of National Convergence R&D: With Focus on the Text Mining)

  • 유기철;이태희;최상현;이정환
    • Journal of Information Technology Applications and Management
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    • 제27권1호
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    • pp.59-73
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    • 2020
  • There is a growing interest in convergence. National R & D is also providing various policies and institutional support to promote convergence research. Convergence research, however, does not clearly specify its characteristics at the academic and government levels. This research proceeds with the process of collecting, refining, analyzing, modeling, verifying and visualizing national R & D data through the National Science and Technology Information Service (NTIS). The method is to derive the convergence research characteristics and to derive through text mining, focusing on the unstructured information of national R & D project data. The study confirmed that there was a difference in perception between the definition of converged research and the research site. In order to improve this, the research suggested that convergence among research subjects, collaboration among research topics reflecting various backgrounds and characteristics of researchers, and analysis of characteristics of convergence research using information were suggested in the process of establishing convergence policy.

A study on the barrier effect with respect to the condition of solid insulation materials in GN2

  • Lee, Hongseok;Mo, Young Kyu;Lee, Onyou;Kim, Junil;Bang, Seungmin;Kang, Jong O;Nam, Seokho;Kang, Hyoungku
    • 한국초전도ㆍ저온공학회논문지
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    • 제17권1호
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    • pp.44-47
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    • 2015
  • High voltage superconducting apparatuses have been developed presently around the world under AC and DC sources. In order to improve electrical reliability of superconducting apparatuses with AC and DC networks, a study on the DC as well as the AC electrical breakdown characteristics of cryogenic insulations should be conducted for developing a high voltage superconducting apparatus. Recently, a sub-cooled liquid nitrogen cooling system is known to be promising method for developing a high voltage superconducting apparatus. A sub-cooled liquid nitrogen cooling system uses gaseous nitrogen to control the pressure and enhance the dielectric characteristics. However, the dielectric characteristics of gaseous nitrogen are not enough to satisfy the grade of insulation for a high voltage superconducting apparatus. In this case, the application of solid insulating barriers is regarded as an effective method to reinforce the dielectric characteristics of a high voltage superconducting apparatus. In this paper, it is dealt with a barrier effect on the DC and AC dielectric characteristics of gaseous nitrogen with respect to the position and number of solid insulating barriers. As results, the DC and AC electrical breakdown characteristics by various barrier effects is verified.

식물 품종 및 종자의 품질평가 기준에 대한 규정현황 (Legal Aspects for Quality Evaluation Standard of Plant Variety and Seed)

  • 최근진
    • 한국작물학회지
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    • 제47권
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    • pp.200-215
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    • 2002
  • There are some international standards and organization controling the quality characteristics of varieties and seeds such as UPOV, OECD, ISTA, AOSA. The National List system to check variety performance such as quality characteristics of plant varieties and seeds was established by each countries. The UPOV (International Union for the Protection of New varieties of Plant) regulates the requirement of plant variety protection that is distinctness (D), uniformity (U), stability (S) (here in after called DUS), Novelty and Denomination, and some quality characteristics are used to examine the requirement of plant variety protection by each crops. OECD (Organization for Economic Cooperation Development) seed scheme regulates the seed certification for seed trade between countries. ISTA (International Seed Testing Association) and AOSA(Association for Official Seed Analyst) regulates the seed analysis standard and methods. Most of the countries in Europe has the National List system, which check the value for cultivation and use(VCU), that is to say, variety performance such as yield, quality and stress to environment. All the seeds should be enlisted in the National List before sell the seed in their country. All the quality characteristics checked variety performance are for instance, amylose and amylopectin content in rice, molting quality, $\beta$-glucan, protein in barley, protein and sugar content in soybean, sugar and amylopectin content in corn etc. Conditions for the protection of new variety of plant are DUS. Quality characteristics may be the important characteristics and used to check DUS in crop by crop. It is very important to develop a new characteristics and establish standard method fur examine the VCU and DUS test for each crop.

원적외선 난방시스템이 방울토마토 생육에 미치는 영향 (Growth Characteristics of Cherry Tomato in Greenhouse using Far Infrared Heating Systems)

  • 김희준;리혁;강태환;녕효봉;한충수;조성찬
    • Journal of Biosystems Engineering
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    • 제34권3호
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    • pp.161-166
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    • 2009
  • This study was conducted to investigate the growth characteristics of cherry tomatoes in greenhouse using far infrared heating system. The far infrared greenhouse heating systems were installed in two ways on the greenhouse side wall and at the greenhouse ceiling. The heating characteristics of far infrared heating system were analyzed by investigating the heating load, internal temperature, energy consumption, growth characteristics and quality evaluation. The results were compared with heated air heating system using kerosene. The results showed that tomatoes grown in the greenhouse with the far infrared heating system had relatively better plant height, leaf length, leaf width, stem diameter than ones from the greenhouse with hot air heating system and both heating methods had no significant difference on Cherry tomato sugar contents. At the same time, the far infrared heating system reduced heating cost from 34.5 to 41.4% on comparing with hot air heating system.

인슐레이션을 제거한 소형 초전도 회전자 디자인 (Design of a small size insulationless superconducting rotor)

  • 김광민;정성준;김경훈;김남원;박민원;유인근;박태준;김태원
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2011년도 제42회 하계학술대회
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    • pp.792-793
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    • 2011
  • The purpose of this paper is to study the thermal and mechanical characteristics of HTS (high temperature superconductor) field magnet according to the design of a small size superconducting rotor without insulation. First, basic design data of superconducting rotor were acquired through electromagnetic analysis. Based on these data, analysis regarding mechanical and thermal characteristics of HTS field magnet was executed. Anisotropic condition was considered in the mechanical characteristics of HTS field magnet. Average values of specific heat and heat conductivity up to 30 K were used during the analysis of thermal characteristics. Analysis results show superior mechanical and thermal characteristics of insulationless HTS field magnet compared with insulated HTS field magnet.

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Structural and Optical Characteristics of High Quality ZnO Thin Films Grown on Glass Substrates Using an Ultrathin Graphite Layer

  • Park, Suk In;Heo, Jaehyuk;Baek, Hyeonjun;Jo, Janghyun;Chung, Kunook;Yi, Gyu-Chul
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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    • pp.302.1-302.1
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    • 2014
  • We report the growth of high quality zinc oxide (ZnO) thin films on amorphous glass substrates and their structural and optical characteristics. For the growth of ZnO films, mechanically exfoliated ultrathin graphite or graphene layers were used as an intermediate layer because ZnO does not have any heteroepitaxial relationship with the amorphous substrates, which significantly improved the crystallinity of the ZnO films. Structural and optical characteristics of the films were investigated using scanning and transmission electron microscopy, x-ray diffraction, and variable temperature photoluminescence spectroscopy. High crystallinity and excellent optical characteristics such as stimulated emission were exhibited from the high quality ZnO films grown on glass substrates.

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3상 전압변동발생기의 직렬변압기 바이패스용 SCR의 스위칭 특성해석 (Switching Characteristics Analysis of Bypass SCR for Series Transformer in 3-phase Voltage Disturbance Generator)

  • 송웅협;박해영;노의철;김인동;김흥근;전태원
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2010년도 하계학술대회 논문집
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    • pp.71-72
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    • 2010
  • This paper deals with the SCR thyristor switching characteristics of a 3-phase voltage disturbance generator. The series transformers of the generator require bypass SCR thyristors to provide the source voltage to the output terminal in normal operating mode. The SCR thyristor switching characteristics is quite different according to the connection point to the series transformer. The switching characteristics is analysed and verified through simulation results.

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3상 전압변동발생기의 직렬변압기 바이패스용 SCR의 스위칭 특성해석 (Switching Characteristics Analysis of Bypass SCR for Series Transformer in 3-phase Voltage Disturbance Generator)

  • 송웅협;박해영;노의철;김인동;김흥근;전태원
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2010년도 하계학술대회 논문집
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    • pp.532-533
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    • 2010
  • This paper deals with the SCR thyristor switching characteristics of a 3-phase voltage disturbance generator. The series transformers of the generator require bypass SCR thyristors to provide the source voltage to the output terminal in normal operating mode. The SCR thyristor switching characteristics is quite different according to the connection point to the series transformer. The switching characteristics is analysed and verified through simulation results.

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유한요소법을 이용한 정자계형 Wobble 모터와 정전형 Wobble 모터의 토오크 특성 비교 (Torque Characteristics Comparision of Magnetostatic Wobble Motor with Electrosta1 using Finite Element Method)

  • 우성봉;이은웅;오영웅;윤서진;최재영
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 A
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    • pp.336-338
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    • 1999
  • This paper analyzes the torque characteristics with the structure of magnetostatic wobble motor and then compares the torque characteristics of magnetostatic wobble motor with those of electrostatic wobble motor using F.E.M. Through the results, we investigates how design parameters' change affect torque characteristics.

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1.2kW급 연료전지의 전력변환기의 연계 특성 (The Grid Connected Characteristics of 1.2kW Fuel-cell Converter)

  • 료단건;손경종;조수억;박성준;최준호;문채주
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2007년도 하계학술대회 논문집
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    • pp.438-440
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    • 2007
  • This paper shows a new kind of push-pull switching converter for fuel-cell system and analyses the connected characteristics of it. In these characteristics, we are concerned about the high harmonic rate of output current, we also have designed the filter system for the inverter. Besides, the characteristics should be certified better if the ripple of the fuel-cell output current has been eliminated.

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