• Title/Summary/Keyword: Special-plant

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Sciaphila nana Blume (Triuridaceae) : Unrecorded species from Korean flora

  • Yim, Eun-Young;Kim, Moon-Hong;Song, Gwanpil
    • Korean Journal of Plant Taxonomy
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    • v.41 no.3
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    • pp.242-245
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    • 2011
  • In this study, we described and illustrated an unrecorded species from the Korean flora, Sciaphila nana Blume, which is included in the order Pandanales and the family Triuridaceae. This taxon was found at Mul Oreum in Namwon-eup, Seogwipo-si, Jeju Special Self-Governing Province for the first time in Korea. The order Pandanales can be distinguished from the order Liliales by the anomocytic or tetracytic stomata and syncarpous or apocarpous gynoecia of the Pandanales. The family Triuridaceae and the other four taxa in the Pandanales, Cyclanthaceae, Pandanaceae, Stemonaceae, and Velloziaceae, are easily distinguished because the Triuridaceae are microtrophic herbs with scaly leaves. S. nana has a subulate style with a glabrous apex, ovate to narrow ovate leaves and bracts, male perianth segments with a knob-like structure at the apex, and a dimorphic perianth. Therefore, it is easily distinguished from S. tenella, S. multiflora, S. secundiflora, S. thaidanica, S. ramosa, and S. arfakiana.

Studies on Juvenile Tissue Grafting of Some Special-use-Trees (II) An Experiment on Inverted Radicle Grafting of Crop-Tree-Species (특용수종의 유대접목에 관한 연구 (II) 유실수종의 임면지유근역위접목 및 유근역위아접에 관하여(예보))

  • 박규수
    • Journal of Plant Biology
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    • v.11 no.3
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    • pp.8-17
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    • 1968
  • A grafting method, cleft grafting of ordinary dormant scion into an inverted radicle of a germinated seed was tested with good success for chestnut as well as for walnut trees. It was seen that verticilate roots which were produced from the cut and of radicle after grafting made a complete union with scion and made healthy development to produce a successful graft. The radicle before secondary rootlets emerged from its rooting zone was proved to be best stock for inverted radicle grafting. The dormant but was also used for grafting scion with success in this method. Though green house grafting gives higher survival, field grafting was also feasible by this method. Those early growing geason after grafting, the later development of root system and the shoot of the graft were to be studied in the future.

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Development of a robot system for removing top dross on a zinc pot (용융아연욕 부유물 제거용 로봇시스템 개발)

  • 임태균;박상덕;이옥산
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.1488-1491
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    • 1996
  • Throughout CGL(Continuous Galvanizing Line) in steel works, zinc-coated steel sheets are produced which are used where long-running corrosion resistivity is required. During the galvanizing process, top dross is created and floated on the zinc pot. Because the dross leaves ill patterns on the coated sheets, it is removed manually with shovel-like tools in about twenty minutes. Because, however, the working environment is very noisy, hot and harmful to human workers, a robot system is developed and implemented on a real plant to automatically remove the top dross. It consists of a robot and its carriage system, a pot level sensor, a system controller, and special tools to collect, pick up, and put the top dross into a dross waste basket. A system software is developed to monitor the system status. A series of tests were performed to verify the robot motion and adaptation to working conditions, and proved successful work.

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Development of a tele-robotic system for steam generator maintenance works (원전 증기발생기 유지보수용 원격로봇 시스템 개발)

  • 황석용;김창회;김승호
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.1519-1522
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    • 1996
  • In this paper, we have developed a tele-robotic system for nozzle dam installation/removal works and tube relating maintenance works inside unclear power plant steam generator. Developed tele-robotic system consists of many hardwares including robot and a control system. Based on the 3 dimensional graphic simulation, a 6 D.O.F. hydraulic actuated robot and a 2 D.O.F. robot install/removal device have been developed. And also we deviced special tools for nozzle dam carry and bolting. For the tele-robot and other devices to be controlled at the nonradioactive area outside reactor containment building, we developed a tele-robot control system consisting of supervisory controller and remote controller.

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Temperature Effect on Seed Germination and Seedling Growth of Angelica acutilobu

  • Choi, Seong-Kyu;Yun, Kyeong-Won
    • Plant Resources
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    • v.5 no.3
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    • pp.192-195
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    • 2002
  • Special objective of this study is to investigate morphological characteristics of seeds and effects of environmental factors such as light and temperature on their germination and seedling growth of Angelica acutilobu in Umbelliferae plants, using them as oriental medicine materials. Seed shape of Angelica acutilobu is ovate. Color of seed coats varied from yellow to dark brown. Seed size was 5.5 mm in length, 4.0mm in width. One thousand-seed weight of Angelica acutilobus was 3,210mg. Optimum temperatures for seed germination and seedling growth ranged from 20 to $25^{\circ}C$.

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Analysis of Heat Treatment Process for Large Forgings Considering Phase Transformation (대형 단조품 담금질 과정의 조직 및 응력분포 해석)

  • 이정호;이부윤;전제영;이명렬;조종래
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1996.11a
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    • pp.964-968
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    • 1996
  • The demands of size and quality of large steel shaft forgings for ship building, power plant, steel plant, etc. are rapidly increasing, and some of these productions are manufactured from ingot weighing more than 300 tons. For use as rotating components. shafts require toughness, strength and homogeneity, and therefore are produced through a variety of heat treatments. According to the increase of ingot size, micro- and macrosegregation and also mass effect of the product increase. Thus, special care should be paid to the heat treatment of such large shaft forgings. In this paper, the heat treatment of large shaft forgings such as rotor and back-up roll is calculated using the commercial finite element code SYSWELD. Calculated distributions of temperature and phase are compared with experimental data. The continuous cooling transformation diagram, thermal and mechanical properites of each phase are used. The phase proportion, hardness and residual stress during water quenching are discussed.

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Development Length of High-Strength Standard Hooked Bars (550MPa) in Nuclear Power Plant Structures (고강도철근(550MPa)의 원전구조물 적용을 위한 표준갈고리 정착설계)

  • Lee, Byung Soo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2018.05a
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    • pp.99-100
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    • 2018
  • Because of the congestion problems, the high-strength reinforcements are expected to be used in nuclear power plant structures in the near future. According to ACI 349-13, it is permitted to use the high-strength(550MPa) hooked bars in design of development length, but there is no special equation for high-strength bars. In order to reflect the anchorage capacity and behavior properties of high-strength bars with large-diameter(43 & 57mm), it is necessary to develope the new development length equation for large-size and high-strength bars.

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Features of Foliar Epidermis and Stomata in Some Euphorbiaceae Subfamily Oldfieldioideae

  • Raju, Vatsavaya S.
    • Journal of Plant Biology
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    • v.31 no.2
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    • pp.143-153
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    • 1988
  • The features offoliar epidermis and stomata are studied in nine genera representing all the four tribes of the subfamily Oldfieldioideae of the family Euphorbiaceae. On both sides of the leaf, the cuticle is generally smooth with more or less straight epidermal anticlinal walls. The epidermal cells are polygonal and their size varied with species on both sides. The costal cells are either distinct (Dissiliaria, Oldfieldia, etc.) or indistinct (Caletieae). In the taxa examined, the stomata are confined to the abaxial epidermis and diffusely orientated except in Caletieae. They are basically of brachyparacytic type; however, they are anomocytic in Androstachys and of a special type in Mischodon. A systematic consideraton of these features showed that they aer not only useful in revealing relationships within the subfamily but also of acid in the classification.

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Development Length of High-Strength Straight Bars (550MPa) in Nuclear Power Plant Structures (고강도철근(550MPa)의 원전구조물 적용을 위한 직선철근의 정착설계)

  • Lee, Byung Soo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2018.11a
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    • pp.110-111
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    • 2018
  • Because of the congestion problems, the high-strength reinforcements are expected to be used in nuclear power plant structures in the near future. According to ACI 349-13, it is permitted to use the high-strength(550MPa) straight bars in design of development length, but there is no special equation for high-strength bars. In order to reflect the anchorage capacity and behavior properties of high-strength straight bars with large-diameter(43 & 57mm), it is necessary to find the modified factor or develop the new development length equation for large-size and high-strength bars.

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Methods and Systems for High-temperature Strain Measurement of the Main Steam Pipe of a Boiler of a Power Plant While in Service

  • Guang, Chen;Qibo, Feng;Keqin, Ding
    • Journal of the Optical Society of Korea
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    • v.20 no.6
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    • pp.770-777
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    • 2016
  • It has been a challenge for researchers to accurately measure high temperature creep strain online without damaging the mechanical properties of the pipe surface. To this end, a noncontact method for measuring high temperature strain of a main steam pipe based on digital image correlation was proposed, and a system for monitoring of high temperature strain was designed and developed. Wavelet thresholding was used for denoising measurement data. The sub-pixel displacement search algorithm with curved surface fitting was improved to increase measurement accuracy. A field test was carried out to investigate the designed monitoring system of high temperature strain. The measuring error was less than $0.4ppm/^{\circ}C$, which meets actual measurement requirements for engineering. Our findings provide a new way to monitor creep damage of the main steam pipe of a boiler of an ultra-supercritical power plant in service.