• Mycobiology
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• v.31 no.3
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• pp.139-144
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• 2003

This study was conducted to investigate physiological characteristics of Trichoderma spp. isolated from Pleurotus spp. Damage tests of Pleurotus spp. and mycotoxins tests of Trichoderma spp. were also done. The optimal growth temperature of Trichoderma spp. was $27{\sim}30^{\circ}C$. Although, T. longibrachiatum was able to grow at $37^{\circ}C$ and grew $30{\sim}40$ times faster than Pleurotus. The colony colour on PDA medium of T. cf. virens was yellowish green, T. longibrachiatum was yellow, and T. harzianum was turning to bright green. In damage tests of Pleurotus by Trichoderma, T. cf. virens caused the most severe damage to Pleurotus. T. longibrachiatum and T. harzianum caused less damage on Pleurotus but were able to cause greater damage to P. eryngii. One of the mushroom cultivars, P. ostreatus 8 was the most resistant to all Trichoderma spp.. Chitinolytic mycotoxin released by Trichoderma spp. caused 52.7% damage to Pleurotus. Mycotoxins released by T. longibrachiatum caused the greatest damaged(78.6%) on P. eryngii.

• Journal of the Korea Institute of Building Construction
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• v.5 no.3 s.17
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• pp.117-124
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• 2005

Quality management in construction industry becomes more significant under the existing conditions such as, increasing higher demand caused by the high value of real estate and extension of the warranty period. Therefore, this study presents the alternative idea related to the current quality management conditions of small and medium construction companies, including the difficulties and problems in qualify management, in order to develop the systematical method for the quality management in small and medium construction company.

• Journal of Mechanical Science and Technology
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• v.17 no.10
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• pp.1583-1596
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• 2003

A study of forced convection in a circular pipe with a partially filled porous medium was numerically investigated. The Brinkman-Forchheimer extension of the Darcy model was used to analyze the and temperature distribution in the porous medium. Our study includes two types of porous layer configurations: (1) a layer attached at the tube wall extending inward towards the centerline and (2) a layer at the centerline extending outward. The effect of several parameters, such as Darcy number, effective viscosity, effective thermal conductivity, and inertia parameter, as well as the effect of geometric parameters, were investigated.

• Parasites, Hosts and Diseases
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• v.38 no.3
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• pp.173-175
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• 2000

The present study examined postmetacercarial changes in the excysted metacercariae of Echinostoma caproni maintained in the defined medium Mixture 199 plus 20% calf serum for 7 days at $41^{\circ}C$. The gas phase was atmospheric air. Each culture was inoculated with 25 excysted metacerariae. Cultures were maintained upright in closed 15 ml plastic centrifuge tubes each containing 10 ml of medium plus 200 units of penicillin/ml and $200{\;}\mu\textrm{g}$ of streptomycin/ml. By 4 days in culture, most metacercariae had voided their excretory concretions. Organisms were clumped or solitary at the bottom of the cultures. Many organisms showed flaring of the oral collar and extension of both the collar and tegumentary spines. By 4 days in culture, posterior protuberances or bumps were noted on many of the organisms and some organisms showed abnormal vesicular growths or blebs at their posterior ends. Some mortality was noted in culture by day 5, but most organisms were still alive when the cultures were terminated on day 7.

• Advances in aircraft and spacecraft science
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• v.3 no.3
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• pp.317-330
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• 2016

Nowadays, the interest of aerospace and automotive industries on virtual testing of medium-frequency vibrational behavior of shallow shell structures is growing. The development of software capable of predicting the vibrational response in such frequency range is still an open question because classical methods (i.e., FEM, SEA) are not fully suitable for the medium-frequency bandwidth. In this context the Variational Theory of Complex Rays (VTCR) is taking place as an ad-hoc technique to address medium-frequency problems. It is a Trefftz method based on a weak variational formulation. It allows great flexibility because any shape function that satisfies the governing equations can be used. This work further develops such theory. In particular, orthotropic materials are introduced in the VTCR formulation for shallow shell structures. A significant numerical example is proposed to show the strategy.

• International Commerce and Information Review
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• v.10 no.1
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• pp.375-393
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• 2008

The purpose of this study is to investigate the Chinese investment environment and analyze the actual investment condition of Korean enterprises in China and examine the points at issue. In general, the investment environment in China shows satisfactory progress. China has a multiple and regional extension policy in investment. And the environment for investment changes to insufficiency of company profit, extension of service market, maintenance of legislative system, and insufficiency of preference about foreign company. There are situations of inclining to manufacturing, inclining of region, preference of independence investment, small-sized investment by small and medium enterprises, difficulty of financial assistance, excess of logistic cost, delay of logistic term, difficulty of settlement of legal dispute and difficulty of taking a relative information in investment of Korean enterprise in China. The results of the study indicate mostly that the investment of Korean enterprise into China needs turnover of service trade-tertiary industry, portfolio of investment territory, cooperation with Chinese enterprise through joint venture investment and a large-scale investment for extension of Chinese domestic market.

• Mycobiology
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• v.39 no.3
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• pp.230-232
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• 2011

In this study, we characterized sporadically occurring sclerotium rot caused by Sclerotium rolfsii in Chinese chive (Allium tuberosum Roth.) in farm fields in Sacheon, Korea. The initial symptom of the disease was water-soaked, which progressed to rotting, wilting, blighting, and eventually death. Further, mycelial mats spread over the lesions near the soil line, and sclerotia formed on the scaly stem and leaves. The sclerotia were globoid, 1~3 mm, and white to brown. The optimum temperature for growth and sclerotia formation on potato dextrose agar (PDA) was $30^{\circ}C$. The diameter of the hypae ranged from 4 to 8 ${\mu}m$. Clamp connection was observed on PDA medium after 5 days of incubation. Based on the mycological characteristics, internal transcribed spacer sequence analysis, and pathogenicity test, the causal agent was identified as Sclerotium rolfsii Saccardo. This is the first report of sclerotium rot in Chinese chive caused by S. rolfsii in Korea.

• Plant Resources
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• v.3 no.2
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• pp.135-137
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• 2000

Callus cultures from leaf explants of Gypsophila paniculata L. cv. 'Bristol Fairy' have been tested their growth and morphogenic capacity on Murashige and Skoog medium supplemented with 0.l, 0.5, 1 and 3 mg/L 2,4-D. The frequency of callus formation ranged from 43.3% to 100%. The optimal 2,4-D concentration for promoting callus formation and growth was 0.5 to 3 ㎎/L. 4.2∼ 5.6% of adventitious roots were obtained with the use of 0.1 and 0.5 mg/L 2,4-D. Calli grown well on 1.0 mg/L 2,4-D was the heaviest among the calli grown in various concentrations.

• Journal of Plant Biotechnology
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• v.35 no.2
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• pp.163-167
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• 2008

Adventitious buds appeared within 2 weeks on the base of the petiole explants and increased for two months. A maximum of regeneration (15.6%) was obtained on the medium containing $1.5\;{\mu}M$ TDZ in combination with $1\;{\mu}M$ IBA. To know which explants are the best for the induction of regeneration, three explants such as leaf, petiole and leaf-petiole were used. Among the explant types, the leaf-petiole explant was significantly more effective than leaf and petiole for promoting adventitious shoots, with leaf-petiole inducing at the highest regeneration frequency (33.7%). The regeneration frequency of adventitious shoots in the leaf-petiole explants was significantly affected by leaf size and the position of explants. The leaf-petiole smaller than 5 mm leaf in width was induced at the highest regeneration frequency (68.9%). The smaller leaf sizes, the greater regeneration frequency. Also when the leaves are nearer to the shoot tip, the regeneration frequency is higher. When the rooted micro-shoots were transferred to the soil after growing for 6 weeks in the media, the survival rate was 90%.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.310-310
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• 2017

'Gawaji 1', an early maturing and low amylose content rice variety adaptable to double cropping system with barley as later winter crop., was developed by the crop breeding team of Crop Research Division, GARES, Hwaseong, Korea in 2016. 'Gawaji 1' was derived from a cross between 'Baegjinju' and 'Sangmibyeo' in 2004. This variety had heading date of August 4 in Gyeonggi Province. It had a semi-elect plant type and resistance to lodging with strong culm. Its culm length was 67 cm. This variety had 15 tillers per hill and 104 spikelets per panicle. It was medium grain variety showing 1,000 grain weight of brown rice of 19.3g. Its protein contents of milled rice was 8.2% which was lower than 'Baegjinju'. Its milling ratio was 75.5% which was higher than 'Baegjinju'. The yield of milled rice was 5.0 MT/ha under the ordinary culture of the local adaptability test in 3 areas of Gyeonggi Province for three years. 'Gawaji1' is highly adaptable to Gyeonggi Province, especially to northern region of Han River.