• Structural Engineering and Mechanics
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• v.38 no.5
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• pp.593-618
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• 2011

This paper deals with the problem of the determination of the response of a viscoelastic Bernoulli-Navier beam, which is resting on an elastic medium. Assuming uniaxial bending, the displacement of the beam axis is governed by an integro-differential equation. The compatibility of the displacements between the beam and the elastic medium is imposed through an integral equation. In general and in particular in the case of a Boussinesq medium, the solution has to be pursued numerically. On the contrary, in the case of a Winkler's medium the compatibility equation becomes a linear finite relationship, which allows finding an original analytical solution of the problem for both hereditary and aging behavior of the beam. Some numerical examples complete the paper, in which a comparison is made between the hereditary and the aging model for the creep of the beam.

• Proceedings of KOSOMES biannual meeting
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• 2017.04a
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• pp.132-132
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• 2017

• Journal of Plant Biology
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• v.14 no.2
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• pp.7-10
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• 1971

Haploid cell obta-ined from microspores of Solanum nigrum were cultured on two kinds of medium, "Callus-inducing medium" and "Differentiation medium", in order to conduct histological studies of callus and examine differentiation of plantlets. On the callus-inducing medium the calli grew rapidly. The bulk of callus mass was light brown colored "Wet callus" covered on the surface with thin layers of rough and gleaming "White callus". The wet callus was consisted of parenchyma and meristematic tissues, while the white callus had no meristematic tissues. Large parenchyma cells, by successive divisions, became multicellular or poly nucleate cells which developed later to be meristematic tissues. The calli embedded on the differentiation medium quickly turned to dark brown color. Plantlets, however, came out later from these blackened callus mass. In the callus sectioned about ten weeks after imbedding on the differentiation medium, radially elongated tissue, concentric tissue, epidermis, tracheid-like structure, and plant jprimordia were observed.ure, and plant jprimordia were observed.

• Korean Journal of Food Science and Technology
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• v.53 no.6
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• pp.815-818
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• 2021

The objective of this study was to develop a differential medium with improved selectivity for the isolation of Bacillus cereus. Mannitol egg yolk polymyxin medium supplemented with D-galactose allowed the differentiation of diarrheal- and emetic-type B. cereus through pH monitoring. The pH of the medium decreased significantly when incubating the emetic-type B. cereus, whereas the pH change was not significant when incubating the diarrheal-type. The addition of pH indicators, such as methyl red and phenol red, to the medium allowed visual differentiation between diarrheal- and emetic-type B. cereus. A solid agar medium was also developed by optimizing the concentrations of medium components such as monosaccharides, agar, egg yolk enrichment, pH indicators, and antibiotics. This study indicates the possibility of applying selective media for the differentiation of diarrheal- and emetic-type B. cereus.

• Journal of the Regional Association of Architectural Institute of Korea
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• v.20 no.6
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• pp.25-32
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• 2018

According to the data released by Korea Occupational Safety & Health Agency, construction workers suffering from falling disaster have been increasing continuously for the last five years, and in fact, small and medium construction companies' falling disaster forms over 97% of all every year. This means that to reduce falling disaster significantly, it is needed to get rid of disaster taking place in small and medium construction companies. Here, this study aims to analyze various causes of falling disaster in small and medium construction companies, examine how those factors are correlated with one another, and suggest how to manage the risk of falling disaster effectively. According to the study results, main factors influencing falling disaster in small and medium construction companies are found as follows: Situational Awareness/Risk Perception, Fatigue/Alertness, Communications, Equipment/Facilities, and Personal Protective Equipment (PPE) in the Direct Level, Management/Supervision, Education/Training, and Planning in the Organizational Level, and Management's Commitment to Safety in the Policy Level.

• Journal of the Chungcheong Mathematical Society
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• v.21 no.1
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• pp.71-78
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• 2008

We introduce the homogenized differential systems for fissured medium equations representing the small temperature variation or densities of a fluid in a system consisting of two components.

• Journal of Mushroom
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• v.14 no.3
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• pp.111-118
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• 2016

The medium used for bottle cultivation of mushrooms is made according to a specific workflow; this includes mixing the raw materials, adjusting the moisture content, placing the mixture into bottles, and sterilizing and cooling the medium. Medium composition should be kept constant throughout the year. placed in the bottle, choice of materials, moisture content, weight of the medium, bulk density, nitrogen content, three-phase medium, such as suitable conditions. To achieve constant medium composition a comprehensive model has been established in accordance with the technology developed in the work process with respect to medium compositions piecemeal. By comprehensively applying the various methods to establish medium composition, our country can expect to grow at over four seasons and overcome the many difficulties in mushroom mycelial growth periods, cultivation periods, quantity, and quality.

• Horticultural Science & Technology
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• v.29 no.5
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• pp.488-493
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• 2011

Callus culture initiation of strawberry (Fragaria${\times}$ananassa Duch.) was investigated at different Murashige and Skoog (MS) medium strengths, types and concentrations of plant growth regulators, and incorporating a cold pretreatment period to determine the optimal nutritional and environmental conditions. No high quality callus was induced on MS media without auxin regardless of medium strength. When 6-benzylaminopurine (BA) was combined with indole acetic acid (IAA), naphthalene acetic acid (NAA), and 2,4-dichlorophenoxyacetic acid (2,4-D), high quality callus were highly induced compared to medium supplemented with auxin alone. When $0.5mg{\cdot}L^{-1}$ BA was combined with IAA, NAA, and 2,4-D, high quality callus induction was more effective than the medium supplemented with the other BA concentrations. The best combination of auxin and cytokinin for high quality callus induction was $1.0mg{\cdot}L^{-1}$ NAA and $0.5mg{\cdot}L^{-1}$ BA. Although the differences in callus induction were not significant, high quality callus induction at half strength MS medium was more effective than at full strength medium. When $30g{\cdot}L^{-1}$ sucrose was added to the half strength MS medium, the rate of high quality callus induction increased. The optimum cold pretreatment temperature and period for high quality callus induction were $4^{\circ}C$ and 72 h, respectively. Regeneration rate of high quality callus increased in MS medium supplemented with thidiazuron.

• Korean Journal of Plant Tissue Culture
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• v.22 no.1
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• pp.7-11
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• 1995

Protoplasts were isolated from hypocotyl tissues of 5-day-old Brassica oleracea var capitata Green Challenger seedlings. Several media were used for protoplast culture and shoot regeneration. The shoot-regeneration rapacity of protoplast derived callus depended on the initial culture medium. Protoplasts were cultured in liquid medium (B5 medium supplemented with CaCl2, 2H2O 600mg/L, g1ucose 20g/L, D-mannito1 70g/L, NAA lmg/L, BA lmg/L, 2.4-D 0.25 mg/L)at 27$^{\circ}C$ under the dark After 5 to 10 days, cultlues were diluted with medium with a reduced osmotic stabilizer and then transferred to illuminated conditions. The culture medium was changed with the fresh medium at 7- to 10-day-intervals until the formation of microcallus. Hypocotyl protoplast-derived callus proliferated when transferred to MS medium supplemented with NAA lmg/L, BA 1mg/L and GA$_3$ 0.02mg/L. Upon transfer to MS basal medium without growth regulators, roots were produced. In an attempt to increase the regeneration frequency, 10g/L polyvinylpyrrolidone was added to the regeneration medium, but the shoot regeneration was mot improved. The regenerated whole plants were acclimated in a sterized soilless mixture(vermiculite 2;perlite 2;peat moss1) in a culture room.

• Plant Biotechnology Reports
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• v.3 no.1
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• pp.67-74
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• 2009

An efficient micropropagation protocol based on multiple shoot induction and callus regeneration has been standardized in Sarcostemma brevistigma, a rare medicinal plant. The nodal cuttings were cultured on MS medium supplemented with BA ($0.5-8{\mu}M$) or Kn ($0.5-8{\mu}M$) alone or in combination with NAA ($0.5-1.5{\mu}M$). Maximum multiple shoot induction was observed on MS medium supplemented with $4{\mu}M$ BA. On this medium, 100% cultures responded with an average number of 11.3 shoots per explant. However, the average shoot length was limited to only 0.9 cm on this medium. The addition of $1{\mu}M$ NAA along with $4{\mu}M$ BA gave rise to an average number of 10.9 shoots with an average shoot length of 1.8 cm. Luxuriantly growing callus was obtained on MS medium supplemented with BA ($5{\mu}M$) and 2,4-D ($2{\mu}M$). The callus was subcultured on MS medium supplemented with BA ($2-15{\mu}M$) or Kn ($2-15{\mu}M$) alone or in combination with NAA ($0.5-2{\mu}M$) for shoot organogenesis. Optimum callus regeneration was obtained on MS medium supplemented with $10{\mu}M$ BA and $1{\mu}M$ NAA. On this medium, 100% cultures responded with an average number of 13.4 shoots per culture. The shoots obtained via multiple shoot induction and organogenesis were rooted on half-strength MS medium supplemented with NAA ($1-7{\mu}M$) or IBA ($1-7{\mu}M$). IBA was better than NAA in terms of both the percentage of cultures that responded and the average number of roots per explant. The rooted shoots were successfully transplanted to soil with 86% success. This standardized protocol will help to conserve this rare medicinal plant.