• 제목/요약/키워드: Medium strength

검색결과 863건 처리시간 0.022초

둥근마(Dioscorea opposita Thunb.)의 기내증식을 위한 배지조건 (Medium Constituents for in vitro Multiplication of Chinese Yam (Dioscorea opposita Thunb.))

  • 정은아;권순태
    • 한국자원식물학회지
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    • 제24권2호
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    • pp.208-213
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    • 2011
  • 둥근마 기내 식물체의 증식을 위해서는 고체배지보다 액체배지에서 액아수, 초장, 생체중, 괴경형성의 수가 높아 기내식물체 증식에 효과적이었다. 배지의 무기염류 농도는 MS 기본 염류의 배지에서 액아수와 생체중이 각각 28.8개, 3.6 g로 기본 염류의 양을 반으로 줄이거나 두 배로 늘인 배지에서보다 높았다. 당원으로는 sucrose가 glucose 보다 더 효과적이었고, sucrose의 농도는 60 $g{\cdot}L^{-1}$에서 액아수와 괴경형성수가 가장 높아 효율적이었다. 질소원은 $NH_4NO_3$$KNO_3$의 조성 비율이 $1{\times}{\frac{1}{2}}$인 것이 다른 처리에 비해 생육이 우수한 것으로 나타났다. 배지내 수소이온 농도는 pH 4.8 ~ 6.8 범위내에서 pH간에 뚜렷한 유의 차이를 보이지 않았다. 생장시기별 생장량에 있어서 엽수, 마디수 및 초장은 접종후 2주부터 5주까지 급격히 증가하고 12주까지는 서서히 증가하는 유사한 경향을 보였다. 반면, 생체중은 접종 3주에서 11주까지 꾸준하게 증가하여 최고치에 달했다. 괴경은 접종 2주부터 형성되기 시작하여, 5~8주 사이에 높은 증가율을 가지며 11주에 최고 형성수가 되었다.

AHP 기법을 이용한 우리나라 수산업관측사업의 추진방향에 관한 연구 (A Study on Development Strategies of the Korean Fisheries Outlook Project based on AHP)

  • 남종오;노승국
    • 수산경영론집
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    • 제41권1호
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    • pp.25-52
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    • 2010
  • The purpose of this paper is to suggest major strategies and necessary new projects for the medium- and long-term development of the Korean Fisheries Outlook Project. To suggest the Korean Fisheries Outlook Center with the above purpose, this paper employs Analytic Hierarchy Process analysis based on surveys obtained by special groups related with the KFOP. The survey is broadly composed of two goals; the medium- and long-term development directions and setting up of new furtherance projects. Each goal has upper and lower strategies respectively. The first goal, the medium- and long-term development directions, has four factors as upper strategies. The upper strategies are composed of accuracy, efficiency, timeliness, and political effectiveness of the fisheries outlook information. In addition, each upper strategy has three lower strategies respectively. For example, accuracy of the fisheries outlook information includes strength of data collection function, strength of satellite photography function, and strength of data analysis function. The second goal, setting up of new furtherance projects, has three factors as upper strategies. The upper strategies consist of accuracy promotion of outlook information using high-technique, field expansion of outlook species, and strength of analyzing function on oversea fisheries information. Each upper strategy has three lower strategies respectively. For instant, accuracy promotion of outlook information using high-technique has strength of information analysis function covered from production to consumption, strength of satellite information function, and structure of forecasting model on demand and supply by outlook species. The above upper and lower strategies were analytically drawn out through insightful interviews with special groups such as officials of the government, presidents of the producer and distributor groups, and researchers of the Korea Maritime Institute and other research institutes. As a result of AHP analysis, first, priorities of upper strategies with the medium- and long-term development directions are analyzed as accuracy, timeliness, political effectiveness, and efficiency in order. Also, priorities of all lower strategies reflecting priorities of upper strategies are examined as includes strength of data collection function on the fisheries outlook information, delivery of rapid information on outlook products for all people interested, strength of data analysis function on fisheries outlook information, strength of consumption outlook function on fish products, and strength of early warning system for domestic fish products in order. Second, priorities of upper strategies with the setting up of new furtherance projects are analyzed as accuracy promotion of outlook information using high-technique, field expansion of outlook species, and strength of analysis function on oversea fisheries information in order. In addition, priorities of all lower strategies reflecting priorities of upper strategies are examined as building up of forecasting model on demand and supply by outlook species, strength of information analysis function covering all steps from production to consumption, expansion of consumption outlook for consumers, strength of movement analysis function of oversea farming industry, and outlook expansion of farming species.

Mass Propagation of Sundew, Drosera rotundifolia L. through Shoot Culture

  • Jang, Gi-Won;Park, Ro-Dong
    • Journal of Plant Biotechnology
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    • 제1권2호
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    • pp.97-100
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    • 1999
  • In order to establish in vitro propagation method of sundew, Drosera rotundifolia L., the effects of MS medium concentration, cytokinin type and concentration, pH, and auxin type and concentration on shoot proliferation and root formation were investigated using shoots at 3 month after seed germination. The highest shoot production was obtained with the half strength of MS ($\frac{1}{2}$ MS) medium than with any other strength of MS medium tested. Addition of kinetin or BA in $\frac{1}{2}$ MS medium was strongly suppressed shoot proliferation. The suppression of shoot proliferation was more effective in BA-supplemented $\frac{1}{2}$ MS medium than kinetin-supplemented. The optimum pH of the media for shoot proliferation was pH 5.7-6.7. Shoots were subcultured in $\frac{1}{2}$ MS medium supplemented with 0.5mg/L 2,4-D for rooting every 8 weeks. All subcultured shoots produced extensive root systems after 5 to 6 week culture. Plantlets after root development were planted in plastic pots filled with moss. The survival rate of plantlets was almost 100%. On subculturing every 8 weeks, hundreds of the plants were propagated from a single plant within a year.

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이온강도에 따른 Agar와 공정육묘용 상토에서 기내배양된 딸기 소식물체의 생육 (Growth of Strawberry Plantlets Cultured in Vitro in the Agar or Commercial Plug Medium as Affected by Ionic Strength)

  • 황승재;정병룡
    • 원예과학기술지
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    • 제30권2호
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    • pp.201-207
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    • 2012
  • 본 연구는 딸기 소식물체의 급속대량 증식을 위한 기내배양에서 적정한 지지물과 최적의 MS 배지 이온강도를 구명하기 위해 수행되었다. 딸기($Fragaria$ $ananassa$ 'Houkouwase') 절편체는 지지물로 agar와 Tosilee(상업적 플러그 육묘용 배지) 배지를 사용하고, 공급된 MS 배지는 기본 MS(대조구), 1/2 MS, 1/4 MS의 강도로 공급하여 자가영양배양 하에서 미세증식하였다. Agar 배지에서 생육을 비교했을 때 1/2 MS 강도에서 초장과 근장이 가장 길었다. 또한 1/2 MS 강도에서 지상부 생체중과 건물중, 그리고 엽면적이 1/4 MS와 기본 MS 강도에서보다 우수했다. 기본 MS의 Tosilee 배지에서 딸기 소식물체를 배양했을 때 초장, 근장, 지상부와 지하부의 생체중과건물중이 agar 배지에서 배양했을 때보다 더 양호했다. 자가영양배양을 통한 기내미세번식 딸기 소식 물체는 1/2 MS 강도의 agar 배지에서 배양하기보다는 기본 MS 강도의 토실이배지에서 가장 우수한 생육을 나타냈다.

Effect of Microorganism Sporosarcina pasteurii on the Hydration of Cement Paste

  • Lee, Jun Cheol;Lee, Chang Joon;Chun, Woo Young;Kim, Wha Jung;Chung, Chul-Woo
    • Journal of Microbiology and Biotechnology
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    • 제25권8호
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    • pp.1328-1338
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    • 2015
  • Years of research have shown that the application of microorganisms increases the compressive strength of cement-based material when it is cured in a culture medium. Because the compressive strength is strongly affected by the hydration of cement paste, this research aimed to investigate the role of the microorganism Sporosarcina pasteurii in hydration of cement paste. The microorganism's role was investigated with and without the presence of a urea-CaCl2 culture medium (i.e., without curing the specimens in the culture medium). The results showed that S. pasteurii accelerated the early hydration of cement paste. The addition of the urea-CaCl2 culture medium also increased the speed of hydration. However, no clear evidence of microbially induced calcite precipitation appeared when the microorganisms were directly mixed with cement paste.

다이폴 안테나를 이용한 대지면의 복소 유전상수 측정 (The measurement of the ground complex dielectric constant by using the dipole antennas)

  • 홍성욱;김흥수
    • 한국정보통신학회논문지
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    • 제4권2호
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    • pp.357-363
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    • 2000
  • 가시거리 환경에서 수신 전계강도는 반사매질의 전기적 특성에 의해 변화한다. 매질의 전기적 특성을 구하기 위해 안테나의 편파특성에 대한 반사계수 식과 매질에 대한 복소 유전상수의 관계식을 유도하고 수신전력 식을 이용하여 반사계수와 송수신전력의 관계를 원의 방정식으로 표현하였다. 그리고 측정된 전계강도로부터 매질의 전기적 특성을 구하는 알고리즘을 제시하였다.

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In vitro Organogenesis and Propagation of Heloniopsis orientalis Thunb

  • Jong-Woo Nam;Yoon-Kyung Choi;Kyeong-Mi Cho;Young-Been Kim;Sung Hwan Yim;Kee Hwa Bae
    • Journal of Forest and Environmental Science
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    • 제39권3호
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    • pp.150-154
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    • 2023
  • Heloniopsis orientalis (Liliaceae) is an important horticultural crop native to Korea. Under natural conditions, germination is poor and plant growth is delayed. Therefore, we have developed a vegetative propagation method to produce plants with vigorous growth characteristics via tissue culture. The regenerated shoots were then initiated directly from leaf explants on an MS medium containing either 0.5 to 2.0 mg/L 2,4-D or 1.0 to 3.0 mg/L BA. Healthy plantlets with adventitious roots were formed on the medium supplemented with 1.0 mg/L BA (81%). BA triggered callus initiation without caulogenesis or rhizogenesis, and callus formation was better on the half-strength MS medium than on the full-strength medium. This in vitro propagation protocol will be useful for conservation, as well as for mass propagation.

Strength Increase of Medium Temperature-carbonized PAN Nano Fibers Made by Mechano-electrospinning

  • Kim, J.H.;Bajaj, B.;Yoon, S.J.;Kim, S.H.;Lee, J.R.
    • Composites Research
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    • 제26권3호
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    • pp.160-164
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    • 2013
  • In this study, the effect of phosphoric acid (PA) as a fiber spinning aid on the strength increase of polyacrylonitrile (PAN) nano-fibers by using modified mechano-electrospinning technologies has been analyzed. The medium carbonization temperature of $800^{\circ}C$ has been selected for the future economic production of these new materials. The concentration of PAN in dimethyl sulfoxide (DMSO) was fixed as 5 wt%. The weight fraction of PA was selected as being 2%, 4%, 6%, and 8% in comparison to PAN. These solutions have been used to make the nanofibers. The mechano-electrospinning apparatus installed in KRICT was made by our own design. By using this apparatus the continous and highly aligned precursor nano-fibers have been obtained. The bundle of 50 well aligned nano diameter continuous fibers with the diametr of 10 microns with 6 wt% phosphoric acid for addition showed maximum mechanical properties of 1.6 GPa as tensile strength and 300 GPa as Young's modulus. The weight of final product can be increased 19%, which can improve the economical benefits for the application of these new materials.

A combined pathway of somatic embryogenesis and organogenesis to regenerate radiata pine plants

  • Montalban, I.A.;De Diego, N.;Igartua, E. Aguirre;Setien, A.;Moncalean, P.
    • Plant Biotechnology Reports
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    • 제5권2호
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    • pp.177-186
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    • 2011
  • This study describes for the first time in Pinus genus a plant regeneration system via a combined pathway of somatic embryogenesis and organogenesis from immature seeds of radiata pine. Somatic embryos were obtained from embryogenic line 2162 of Pinus radiata D. Don on EDM basal medium containing $60{\mu}M$ ABA and 6% sucrose. The explants used for organogenesis experiments were either freshly collected somatic embryos or somatic embryos germinated for 1 week. Germination medium was half-strength LP medium, supplemented with 0.2% activated charcoal. Different induction periods and BA concentrations were assayed for shoot induction. After induction treatments, explants were elongated on the same medium used for germination stage. Rooting medium was quarter-strength LP medium supplemented with three different auxin treatments: $1.5mg\;L^{-1}$ 1-naphthalene acetic acid (NAA), $1.5mg\;L^{-1}$ indole-3-butyric acid (IBA) and $1mg\;L^{-1}$ IBA with $0.5mg\;L^{-1}$ NAA (MIX). The effect of the photon flux ($120mmol\;m^{-2}\;s^{-1}$ and darkness) in the first week of the explants in the rooting media was also tested. This methodology could offer an alternative to overcome some problems associated with somatic embryogenesis such as the seasonality of embryogenic tissue (ET) initiation or a low embryo production from the ET, a particularly important issue in the case of genetically transformed ETs.

중형 디젤엔진용 실린더 프레임에 대한 구조해석 (Structural Analysis of Cylinder Frame for Medium-speed Diesel Engine)

  • 손정호;김무승;안성찬
    • 한국마린엔지니어링학회:학술대회논문집
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    • 한국마린엔지니어링학회 2005년도 전기학술대회논문집
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    • pp.144-148
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    • 2005
  • Cylinder frame manufactured by casting is assembled with the components such as cylinder head, cylinder liner and main bearing cap, etc. The mechanical contact between all of the neighboring components due to bolt tightening was taken into consideration. The loads used in structural analysis were the bolt tightening forces induced by hydraulic jack and the dynamic forces calculated from kinematic analysis. The difference of forces between the neighboring cylinders was taken into account. The maximum stress, stress amplitude and mean stress calculated from the results of structural analyses were used to evaluate the static and fatigue strength. Gray cast iron which is material of cylinder frame has the material characteristics of very small elongation and different strength in tension and compression. Based on such an material characteristics, the strength evaluation of cylinder frame was carried out with in-house program developed internally.

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