• Title/Summary/Keyword: Seeding technique

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

  • Lee, Hee-Gyoun
    • Progress in Superconductivity and Cryogenics
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    • v.19 no.2
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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.

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

  • Suh, Hyoung-Min;Kim, Dong-Geun;Lee, Nam-Sook
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.13 no.1
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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-
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1993.10a
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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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Dispersion measurement technique based on a self-seeding laser oscillation of a Fabry-Perot laser (Fabry-Perot 레이저의 자기궤환 레이저 발진을 이용한 색분산 측정법)

  • 윤기홍;송재원;김현덕
    • Korean Journal of Optics and Photonics
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    • v.15 no.2
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    • pp.104-108
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    • 2004
  • A simple dispersion measurement technique has been demonstrated by using a self-seeding laser oscillation of a Fabry-Perot laser through a closed loop. The optical pulses of different wavelengths emitted from the Fabry-Perot laser travel down an optical fiber and the group velocity difference between the pulses due to the chromatic dispersion of the optical fiber is measured through the self-seeding laser oscillation process. The dispersion parameter of the optical fiber is calculated from the measured group velocity difference. The performance of the proposed technique has been confirmed experimentally and the accuracy of dispersion parameter measurement was comparable to that of commercial instruments with expensive equipment and components. The repeatability of the proposed method was better than 0.5%.

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

  • Hwang, Eun Kyoung;Hwang, Il Ki;Park, Eun Jeong;Gong, Yong Geun;Park, Chan Sun
    • Korean Journal of Environmental Biology
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    • v.31 no.4
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    • pp.347-352
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    • 2013
  • Outdoor cultivation experiment was conducted with artificial seeds using free-living gametophytes and zoospores of Ecklonia cava to develop FLG (free-living gametophyte) seeding technique. Growth of thalli between FLG and zoospore seeding groups was compared monthly from May to October 2009 at culture farm in Wando, Korea. In September 2009, thalli in the FLG seeding experimental group were $35.9{\pm}0.8$ cm in length, $24.1{\pm}2.62$ g in weight, $2.32{\pm}0.26$ kg $m^{-1}$ in biomass and $22.0{\pm}2.8$ individuals $m^{-1}$ in density. There were no significant differences in length, weight, biomass and density between FLG and zoospore seeding group. Therefore, the FLG seeding technique could replace the zoospore seeding method which would eventually contribute in restoration and conservation of natural resources.

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

  • 정양희;강성준
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.5 no.6
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    • pp.1128-1135
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    • 2001
  • In this paper, a new HSG-Si formation technology, "seeding method', which employs Si$_2$H$_{6}$-molecule irradiation and annealing, was applied for realizing 64Mbit DRAMs. By using this technique, grain size controlled HSG-Si can be fabricated on in-situ phosphorous-doped amorphous-Si electrode. The new HSG-Si fabrication technology achieves twice the storage capacitance with high reliability for the stacked capacitors. In this technique, optimum process conditions of the phosphorous concentration, storage polysilicon deposition temperature and thickness of hemispherical grain silicon are in the range of 3.0-4.0E19atoms/㎤, 53$0^{\circ}C$ and 400$\AA$, respectively. In the 64M bit DRAM capacitor using optimum process conditions, limit thickness of dielectric nitride is about 65$\AA$.

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

  • Yoon Ki-Hong;Song Jae-Won;Kim Hyun Deok
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.41 no.12
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    • pp.51-57
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    • 2004
  • A simple fiber length measurement technique has been demonstrated by using a self-seeding laser oscillation of a Fabry-Perot laser diode. We induced a self-seeding laser oscillation through a closed-loop by adjusting the modulation frequency of a Fabry-Peort laser diode when the output optical pulse of the laser reinjected into the laser after passing through the closed-loop. The length of a fiber-under-test was calculated from the difference between my two modulation frequencies at which self-seeding laser oscillation occurs at a specific mode. We have experimentally confirmed the technique for various fiber lengths from 0.1 km to 75 km. The relative error between the measurement result of the proposed technique and that of a commercial instrument was less than 0.24 %. The repeatability of the proposed technique was better than 0.1 %.

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
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.44 no.4
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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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Slope Revegetation by Seeding works and Resent Nature Restoration in Japan (일본에 있어서의 파종공에 의한 법면녹화와 자연회복녹화)

  • Hiroshi, Yoshida;Koh, Jeung-Hyun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.8 no.2
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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.

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

  • 정상옥;김지용;안태홍
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2000.10a
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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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