• Title/Summary/Keyword: Effective medium

Search Result 2,513, Processing Time 0.032 seconds

High Frequency Shoot Regeneration from Leaf Explants of Some Chrysanthemum Cultivars

  • Kim, Young Hoe;Park, So Hyeon;Kim, Gyeong Hee;Jeong, Byoung Ryong
    • Journal of Plant Biotechnology
    • /
    • v.6 no.1
    • /
    • pp.51-54
    • /
    • 2004
  • This study was conducted to examine differences in shoot regeneration among chrysanthemum cultivars. Leaf explants of chrysanthemum cultivars 'Sulhwa', 'Puma', 'Geummokseo' and 'Sulpoong' were used. Explants cultured on the medium for 2 weeks formed calli at the cut surfaces. Shoots regenerated on MS basal medium supplemented with various concentration combinations of NAA and BAP. Explants were cultured under cool-white fluorescent lamps with a light intensity of $40\mu{Mm}^{-2}$.$s^{-1}$ for 16 $hday^{-1}$, at $25^{\circ}c$ and 70-80% relative humidity. 'Geummokseo' and 'Sulpoong' were the most responsive cultivars in shoot regeneration. Most effective medium for 'Sulhwa' and 'Puma' was MS basal medium supplemented with 10.0 $\mu{M}$ NAA and 5.0 $\mu{M}$ BAP and for 'Geummokseo' MS supplemented with 10.0$\mu{M}$ NAA and 20.0$\mu{M}$ BAP. Regeneration of multiple shoots was observed on MS basal medium supplemented with 1.0$\mu{M}$ or 10.0 $\mu{M}$ NAA and 5.0$\mu{M}$ BAP. High frequency regeneration of adventitious shoots from leaf explants and efficient induction of root from these regenerated shoots were obtained.

Effect of Medium Composition on Phalaenopsis Micropropagation Using Lateral Buds From Flower Stalks (액아배양에 의한 호접란 대량번식시 배지조성의 영향)

  • Park, Myung-Joo;Park, Soon-Jung;Kim, Doo-Hwan
    • Horticultural Science & Technology
    • /
    • v.16 no.1
    • /
    • pp.42-44
    • /
    • 1998
  • The effect of medium composition on PLB formation and multiplication and shoot regeneration was studied to establish the micropropagation system of the tropical orchid Phalaenopsis. The highest frequence of PLB formation resulted from the VW medium with 1.2 times ion concentration, 1% sucrose, 1.5g/L PVP or 2.5g/L active charcoal, apple and potato extract and 4g/L gellan gum. The highest ratio of PLB multiplication was obtained from the VW medium with 2% sucrose, apple and potato extract and cotton plate. The shoot regeneration was the most effective with the hyponex medium with 3% apple, 3% potato and 4% banana extract.

  • PDF

A Study On The Characteristics Of The Medium Voltage Power Distribution Line Channel By Wideband Channel Impulse Response Measurement Using PN Sequence (PN 시퀀스 방식의 광대역 임펄스 응답 측정을 통한 고압 배전선로 채널 특성 연구)

  • Oh Hui-Myoung;Choi Sung-Soo;Lee Jae-Jo;Kim Kwan-Ho;Whang Keum-Chan
    • The Transactions of the Korean Institute of Electrical Engineers D
    • /
    • v.54 no.1
    • /
    • pp.56-60
    • /
    • 2005
  • In the power-line communication(PLC) systems, the power line is a wired medium. However, the power line channel has the multi-path fading characteristics like the wireless channel in the wireless communication systems because it has the signal reflection and divergence by the impedance mismatching between many branch lines and loads. So the analysis of the multi-path characteristics is very important, and it has been doing by the several measurement methods for the impulse response between the transmitter and the receiver. PN sequence method has originally been used as a wideband impulse response measurement mettled for wireless channel, but it is recently being applied to not only the wireless channel but also the wired channel like the power line channel. This method is more useful and effective for the long distance communication channel like the medium voltage power distribution line with the multi-paths[1]. In this thesis, we have measured impulse response for the medium voltage power distribution line channel by the wideband measurement method using PN sequence, analytically studied the measured data and presented the results.

An Information Systems Operation Framework for Small and Medium Enterprises (중소기업을 위한 정보시스템 운영 프레임웍)

  • Park, Kwang-Ho;Baek, Dong-Hyun
    • Information Systems Review
    • /
    • v.8 no.1
    • /
    • pp.223-239
    • /
    • 2006
  • In digital economy, information systems are recognized as the most critical survival factor of companies. Companies must launch and expand business based on information systems either developed newly or adopted as ERP. However, successful information systems operation shall face many realistic problems. Especially most small and medium enterprises experience many difficulties in systems operation or even give up operating information systems due to unexpected operational problems. This paper suggests a framework for effective information systems operation for small and medium enterprises. The framework is designed through case studies, consisting of service framework, auditing framework, and risk management framework. It is expected that the framework contributes to successful information systems operation in small and medium enterprises.

Enhancement of Apx Toxin Production in Actinobacillus pleuropneumoniae Serotypes 1, 2, and 5 by Optimizing Culture Conditions

  • Dao, Hoai Thu;Do, Van Tan;Truong, Quang Lam;Hahn, Tae-Wook
    • Journal of Microbiology and Biotechnology
    • /
    • v.30 no.7
    • /
    • pp.1037-1043
    • /
    • 2020
  • Actinobacillus pleuropneumoniae (APP) is a causative agent of porcine pleuropneumonia. Therefore, the development of an effective vaccine for APP is necessary. Here, we optimized the culture medium and conditions to enhance the production yields of Apx toxins in APP serotype 1, 2, and 5 cultures. The use of Mycoplasma Broth Base (PPLO) medium improved both the quantity and quality of the harvested Apx toxins compared with Columbia Broth medium. Calcium chloride (CaCl2) was first demonstrated as a stimulation factor for the production of Apx toxins in APP serotype 2 cultures. Cultivation of APP serotype 2 in PPLO medium supplemented with 10 ㎍/ml of nicotinamide adenine dinucleotide (NAD) and 20 mM CaCl2 yielded the highest levels of Apx toxins. These findings suggest that the optimization of the culture medium and conditions increases the concentration of Apx toxins in the supernatants of APP serotype 1, 2, and 5 cultures and may be applied for the development of vaccines against APP infection.

A Draft of Hull Piece Fabrication Line for Small and Medium Sized Shipyards by Object Oriented Analysis (객체지향분석에 의한 중소형 조선소 선체외판 생산설비 계획에 관한 연구)

  • 박명규;문귀호;김원돈
    • Journal of the Korean Institute of Navigation
    • /
    • v.23 no.1
    • /
    • pp.29-43
    • /
    • 1999
  • The production process of the compound-curved hull plates includes hull design, definition, fairing, modeling, lofting, cutting, and forming in sequence. Traditional fabrication methods and shop environment caused low level to productivity in medium and small sized shipyards. The most effective solution to solve those problems is to rationalize the layout of facilities. For the well-balanced development of domestic shipbuilding industry, it is urgently required to reduce the gap between modernized large sized shipyards and traditional small and medium sized shipyards in production technologies and efficiencies. For the efficient and accurate hull piece forming, all information from design to forming should be clarified and organized in a systematic manner. Thus, management of the information plays an important role in the computerized and automated of hull piece forming. The object of this paper is to survey the status of the field, to find out the feasibility and to introduce a draft of hull piece fabrication line for small and medium sized shipyards. The development of required system follows the object oriented technology to extend to simulation based system for carrying out physical product flow and facilities layout analysis. It is feasible to operate such a modernized facility for a group of small and medium shipyards who are unable to have each of their own facility because of its large amount of initial investment and insufficient work load.

  • PDF

Effect of Plant Growth Regulators and Medium Salt Strength on In Vitro Propagation of Belamcanda chinensis DC (범부채의 기내증식에 미치는 식물생장조절물질 및 무기염류농도의 효과)

  • 송원섭
    • Korean Journal of Plant Resources
    • /
    • v.10 no.2
    • /
    • pp.114-121
    • /
    • 1997
  • The effects of plant growth regulators on callus formation and organogenesis in shoot tip explant of Belancanda chinensis were examined. Shoot tip explants cultured in full salt strength of MT(Murashige and Tucker) medium containing 2,4-D 1.0 or 2.0mg/l were vigorously formed callus. Full salt strength of MT medium and 1/2 MT medium supplemented with zeatin 1.0mg/l were more effective than that with combination treatments of 2,4-D on the formation of shoots from calli. When shoots regenerated from shoot tips were transplanted into 1/2 MT medium added with 1.0mg/l, 41% of shoots formed roots.

  • PDF

Studies on the Effect of 2-Chloroethylphosphonic Acid (Ethephon) on the Floral Induction in Photoperiodic Plants (광주기식물의 개화유도에 미치는 2-Chloroethylphosphonic Acid(Ethephon)의 효과에 관한 연구 I. Ethephon에 의한 Lemna perpusilla 6746 개화억제)

  • 맹주선
    • Journal of Plant Biology
    • /
    • v.20 no.2
    • /
    • pp.77-82
    • /
    • 1977
  • The inhibiotory effect of ethphon on the flowering in Lemna perpusilla 6746 was shown to be related to sucrose concentrations and dilution factors of Hutner's medium. When grown in 1/10-strength Hutner's medium under 10(14) cycles, the plants have been completely inhibited in the floral induction by ethephon (>5ppm) in the presence of sucrose (>20 mM) in the meduim. However, in a less diluted Hutner's medium (1/2-strength), the inhibition of flowering by ethephon was observed to be partially diminished by sucrose at a high concentration (30mM), while a low concentration of sucrose enhanced the inhibitory effect of ethephon in flowering. As inductive dark periodswere extended, the effects of both compounds were partially nullified. Since no significant amount of ethylene possibly released in ethephon decomposition in the medium was detected, the inhibitory effect of ethephon in flowering was postulated to be exerted only through ethylene production within the plants. Plants were incubated in 10 ppm ethephon-containing medium during either dark or light periods, singly or periodically. The most effective single treatment with ethephon was observed during the 4th dark period, when formation of floral stimulus was assumed to be completed beyond a critical level. This postulation can be partially supported by a fact that the plants should be exposed to at least more than four consecutive 10(14) cycles for flowering.

  • PDF