• 제목/요약/키워드: Seeding technique

검색결과 81건 처리시간 0.024초

Interior seeding combined with top seeding for the fabrication of single grain REBCO bulk superconductors

  • Lee, Hee-Gyoun
    • 한국초전도ㆍ저온공학회논문지
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    • 제19권2호
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    • pp.14-18
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    • 2017
  • This study presents three dimensional (3-D) seeding technique which is a modification of interior seeding. 3-D seeding is beneficial for shortening the processing period and enhancing the magnetic properties of REBCO bulk superconductors fabricated by melt growth. Oxygen channels were provided by using divided powder compacts instead of by using a rubber insert. Microstructure observations revealed that the grains grown from the seeds impinged each other and formed low angle grain boundaries of (001)/(001). It has been shown that the 3-D seeding technique reduces the volume fraction of a-c growth sector and thereby maximizes the area of a-b growth sector which attribute to the high magnetic characteristics of single grain REBCO bulk superconductors.

자생식물 종자칩(seed chip)을 이용한 훼손사면의 복원 공법의 개발 (Development of Restoration Technology Using Native Plants Seed Chip for Various Disturbed Slopes)

  • 서형민;김동근;이남숙
    • 한국환경복원기술학회지
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    • 제13권1호
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    • pp.112-120
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    • 2010
  • This study was carried out to develop the environmental friendly restoration technique for various disturbed slopes using native plants seed chips. As the result of the separated seeding using the developed seed chips of native plant combination, average germination rate and survival rate of trees, shrubs, and herbs were higher than those of the direct seeding, as 79~70%, 83~73%, and 59~53% or so, respectively. Also, the germination rates and the survival rates of trees, shrubs, and herbs in the separated seeding by the native plants seed chips were 10~15 times higher than those of the direct seeding. Numbers of plants survived were at least 10 times of that of the simple seeding. The native plants seed chip technique is more efficient in soil slopes compared with stone slopes. The application of the native plants seed chip technique makes the restoration stabilized through the herbs dominant vegetation to the woody dominant 1 within 3 years, and the Landscapes also changed from herbs to variously combined herbs and woody. The technique using native plants seed chips that can be applicable to various disturbed slops is more efficient than conventional restoration techniques in the respect of economics and landscape.

Development of Direct-Wet-Rice-Seedling Machines in Korea

  • Rhee, Joong-Young;Lee, Chong-Ho-
    • 한국농업기계학회:학술대회논문집
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    • 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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    • pp.256-266
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    • 1993
  • History , achievement and future of direct-wet-rice-seeding technique in Korea and problems encountered in on-farming research were introduced. Some farmers are very eager to lower production cost and save labor. Their effort results in several direct-wet-seeding methods and seeding machines. The design problems and improvement points related to the direct -wet-rice-seeding machines were drawn out of field test.

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Fabry-Perot 레이저의 자기궤환 레이저 발진을 이용한 색분산 측정법 (Dispersion measurement technique based on a self-seeding laser oscillation of a Fabry-Perot laser)

  • 윤기홍;송재원;김현덕
    • 한국광학회지
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    • 제15권2호
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    • pp.104-108
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    • 2004
  • 폐경로를 통한 Fabry-Perot 레이저의 자기궤환 레이저 발진(self-seeding laser oscillation)을 이용하여 구조가 간단하고 경제적인 색분산(chromatic dispersion) 측정법을 제안하였다. 저가의 Fabry-Perot 레이저를 이용하여 광펄스들을 생성하고, 광섬유를 통해 전송되는 광펄스들 사이의 군속도 차(group delay difference)를 Fabry-Perot 레이저의 자기궤환 발진 현상을 통해 감지함으로써 광섬유의 색분산계수를 측정할 수 있도록 하였다. 제안된 측정법에 따라 구현된 측정 장치는 고가의 상용 계측기와 비슷한 수준의 색분산계수 측정 정확도를 제공하고, 재현성은 0.5%보다 좋음을 실험적으로 검증하였다.

자연자원 회복을 위한 감태(Ecklonia cava Kjellman)의 인공양식기법 (Cultivation Technique of Ecklonia cava Kjellman for Restoration of Natural Resources)

  • 황은경;황일기;박은정;공용근;박찬선
    • 환경생물
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    • 제31권4호
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    • pp.347-352
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    • 2013
  • 감태의 인공채묘시 유주자 및 유리배우체를 채묘하여 양성 생장도를 비교하므로써, 유리배우체의 대량양식 이용 가능성을 시험하였다. 2008년 11월에 유주자 및 유리배우체를 채묘한 채묘틀을 이용하여 2009년 5월부터 10월까지 전남 완도군 약산면 시험어장에서 양성 생장도를 비교하였다. 유주자 및 유리배우체 채묘 실험구에서 감태 엽체의 엽장과 생체량 등은 유의한 차이를 보이지 않았다.

Seeding Method를 이용한 인이 도우핑된 Amorphous-Si에서의 HSG형성 조건 (Hemispherical Grained Silicon formation Condition on In-Situ Phosphorous Doped Amorphous-Si Using The Seeding Method)

  • 정양희;강성준
    • 한국정보통신학회논문지
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    • 제5권6호
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    • pp.1128-1135
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    • 2001
  • 본 논문에서는 HSG형성을 위한 Si$_2$H$_{6}$의 조사와 어닐링을 통한 seeding method를 64Mbit DRAM에 적용하였다. 이 기술을 사용함으로서 인이 도우핑된 Amorphous 실리콘의 전극에 HSG grain 크기를 조절할 수 있었고, 이 새로운 HSG형성조건은 기존의 stack 캐패시터보다 약 2배의 정전용량을 확보할 수 있었다. 이와같은 방법을 이용한 HSG형성에서 인농도, 저장폴리 증착온도 및 HSG의 두께에 대한 공정 최적 조건으로는 각각 3.0-4.OE19atoms/㎤ , 53$0^{\circ}C$ 및 400$\AA$이었다. 이들 최적화된 공정조건으로 64M bit DRAM 캐패시터에 적용시 질화막의 두께 한계는 65$\AA$으로 확인되었다.

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Effects of Seeding Date and Planting Spaces on Growth and Yield of Swordbean (Canavalia gladiata DC.)

  • Lee, Jae-Wung;Kim, Ik-Je;Ryu, In-Mo;Park, Seong-Gyu;Choi, Gwan-Soon;Kwon, Yong-Woong
    • 한국작물학회지
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    • 제44권4호
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    • pp.364-367
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    • 1999
  • Swordbean was recently introduced to Korea, and cultural technique for stable production, e.g. optimum seeding date and planting space, has not been established. This experiment was conducted to elucidate the changes of growth characteristics, yield components, and yield as affected by different seeding dates and planting spaces. Days to flowering was shortened by 4∼28 days as seeding was delayed. Stem diameter, number of pods per plant, number of seeds per plant, 100-seed weight, and seed yield tended to increase with delaying seeding up to 5 April and then to decrease with further delaying seeding. These results indicate that optimum seeding date of swordbean in unheated polyvinyl house would be early April. Although, the swordbean exhibited large increases in plant height, number of branches per plant, and stem diameter at the wider spacings, planting space could be decreased to the 60 cm plant-spacing and 30 cm row-spacing with no deleterious effect on yield.

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Fabry-Perot 레이저의 자기궤환 레이저 발진을 이용한 광섬유 길이 측정법 (Fiber Length Measurement Technique based on a Self-Seeding Laser Oscillation of a Fabry-Perot Laser Diode)

  • 윤기홍;송재원;김현덕
    • 대한전자공학회논문지SD
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    • 제41권12호
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    • pp.51-57
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    • 2004
  • 본 논문에서는 폐경로를 통한 Fabry-Perot 레이저의 자기궤환 레이저 발진 현상을 이용하여 새로운 광섬유 길이 측정 방법을 제안하였다. Fabry-Perot 레이저에 변조전류를 인가하여 생성된 광펄스를 피측정 광섬유를 포함하는 폐경로를 통과한 후 다시 레이저로 입사시키면 특정 변조주파수에서 자기궤환 레이저 발진이 유도될 수 있다. 제안된 측정법에서는 특정 모드에서 자기궤환 레이저 발진을 유도하기 위한 변조주파수들을 측정하고, 이 변조주파수들 사이의 차를 이용하여 광섬유의 길이를 계산하도록 한다. 제안된 측정법을 이용하여 0.1 ∼ 75 km 범위의 피측정 광섬유의 길이 측정을 수행하였고, 측정결과는 기존의 상용 계측기를 사용한 측정 결과와 잘 일치함을 실험적으로 검증하였다. 상용 계측기와의 상대 오차는 0.24 % 이하였고, 반복측정오차(repeatability)는 0.1 % 보다 작았다.

일본에 있어서의 파종공에 의한 법면녹화와 자연회복녹화 (Slope Revegetation by Seeding works and Resent Nature Restoration in Japan)

  • 요시다 히로시;고정현
    • 한국환경복원기술학회지
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    • 제8권2호
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    • pp.83-89
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    • 2005
  • The historical changes of seeding work in Japan, the typical slope revegetation method, is possible to divide into five periods as follows; 1) The early period after creation(1927-1948) 2) The spreading period of modern revegetation work with manpower(1947-1958) 3) The spreading period of rapid revegetation technique using exotic grasses with machineries(1959-1985${\dots}$) 4) The spreading period of rapid reforestation technique by fast growing species mainly using leguminous shrub species(1986-1995${\dots}$) 5)The developing period of nature restoration technique using endemic arborous species(1996-) The evaluation basis of vegetated condition after slope seeding has been described to a official guide book, "The Standards of Slope Stabilizing Works" It was mainly revised three times after first edition in 1972, and also the point of evaluation basis changed from the vegetation coverage to the density of woody plant through the 3rd period and the 4th period Recently main purpose of slope seeding has been developing from the erosion protection to the nature restoration in the current of the 5th period, and "The tentative guidelines of slope nature restoration" was announced by The Slope Revegetation Section of Japanese Society of Revegetation Technology in 2004. It was proposed the planning techniques of using suitable seeds/plants based on the preservation level at the real each construction sites Consequently, at present the importance of advanced monitoring methods for vegetation maintenance and plant sociologic survey to evaluate the plant succession is increasing.

직파재배 벼의 영농기법 및 비용 절감 효과 - 현장 사례 연구(관개배수 \circled1) (Cropping techniques and cost reduction of direct seeded rice - A case study)

  • 정상옥;김지용;안태홍
    • 한국농공학회:학술대회논문집
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    • 한국농공학회 2000년도 학술발표회 발표논문집
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    • pp.144-150
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    • 2000
  • A field case study was performed to investigate optimum cropping technique of direct seeded rice. In addition, an economic analysis was made to see the effect of this method. Field study was performed at a 2.1㏊ paddy field in Kimjae city, Chonbuk province from 1991 to 1999. Various direct seeding method such as dryland seeding, wetland seeding, and no-till wetland seeding were introduced. Optimum cropping techniques such as when and how to manage the rotary till, water supply, herbicide application, and ponding depth were developed for different cropping methods. Based on this study ₩640,000 per ㏊ can be saved by direct seeding due to no nursery cost, and ₩l,220,000 per ㏊ can be saved by no-till and no nursery cost. With further study these cropping techniques including the no-till direct deeding proves to be advantageous these can be adopted for the most of the paddy fields in Korea.

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