• Journal of Bio-Environment Control
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• v.11 no.1
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• pp.1-4
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• 2002

The occurrence rate of russet in 'Whangkeumbae' pear showed significant difference by years because the russet occurrence is greatly affected by the amount of rainfall. This study was conducted to analyse the relationship between rainfall and russet occurrence by artificial treatment of high humidity. Under high relative humidity condition, stomatal resistance decreased and average fruit weight was higher since the increased net photosynthesis rate accumulation accelerated fruit growth. The russet occurrence began on July 25, when the growth speed of fruit weight and fruit surface is the most fast. Russet occurrence rate was higher in high relative humidity condition because the fruit growth was accelerated. Since the fruit calcium concentration change is extreme in late July, it is assumed that the deceased calcium content is related to the occurrence of russet in 'Whangkeumbae' pear, When the high relative humidity condition is maintained after rainfall, the amount of net photosynthesis rate increase and fruit growth is accelerated. Therefore, the unbalance in the amounts of transferred photosynthesis assimilation product, water and mineral elements would be one of the reasons for the russet occurrence in 'Whangkeumbae' pear.

• Korean journal of applied entomology
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• v.49 no.3
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• pp.233-239
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• 2010

Seasonal occurrence and suitable time of control of Tetranychus kanzawai along with the control efficacy of the alternative use of natural predator and miticide was investigated in Rubus coreanus (Miquel). T. kanzawai appeared in late May with its peak between June and July, and decreased after August in R. coreanus. In Iksan, T. kanzawai estimates show peaks 2~4 times per year during the investigation periods from 2006 to 2008 in R. coreanus fields. Suitable time of control of T. kanzawai was in early to mid May. And control effects of T. kanzawai was improved with an alternated control plot, treating miticides in early-occurrence of T. kanzawai and then releasing the natural predator (Phytoseiulus persimilis Anthias-Henriot). Also, the yields of R. coreanus was highest in the alternated control plot of 638kg/10a compared to non-treatment of 559kg/10a.

• The Korean Journal of Mycology
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• v.27 no.6 s.93
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• pp.420-423
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• 1999

A Sciarid fly, Lycoriella mali was a serious pest in commercial production of the cultivated mushroom, Pleurotus ostreatus. It was found in light trap and compost samples taken from mushroom houses during all growing seasons. The fly population 'was increased with the development of mushroom growth, the larvae occurred about 30 days after spawn inoculation in compost. The highest population was developed spring cultivation season (March to June) and decreased during summer season (August to September). The larvae feed on mycellium and compost; injury to the growing mushroom mycellium and the subsequent consumption of the primordia; they entered and tunneld sporospore stem and infect pinhead formation which would be resulted in decrease of mushroom yield.

• Journal of Sericultural and Entomological Science
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• v.36 no.2
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• pp.110-114
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• 1994

Abnormally cool and wet weather conditions during the summer of 1993 offered an opportunity to evaluate the effects of abnormal weather conditions on mulberry growth and to develop cultivation practicies to reduce leaf yield loss under the similar abnormal weather conditions. Different methods of nutrient supplementation were evaluated in Suwon and Kongju. Nitrogen was supplemented by foliar spray of urea(1.7%) or composite chemical fertilizer Jamsibiryo #8, or by the application of ammonium sulfate(60kg/ha) to the soil. During the period between the late June and the early September which corresponds to the mulberry growing season after summer pruning, mean temperature was 1.4$^{\circ}C$ lower and precipitation 83mm higher than normal year. This weather condition in 1993 caused reduction in leaf yield by 16.4% than common year. Soil nitrogen content decreased due to higher precipitation. Leaf yield loss was reduced by the supplementation of nitrogen to the soil. Leaf nitrogen content increased with the foliar urea spray and nitrogen supplementation to the soil.

• Journal of Bio-Environment Control
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• v.6 no.3
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• pp.143-150
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• 1997

In order to produce young leaf of butterbur(Petasites japoflicus MAX.) in early spring, the planting date and relationship between abscisic acid(ABA) content and dormancy were investigated. Under open field condition, the dormancy of rootstock was initiated in the beginning of October, was the deepest in the middle of November and was completely broken in the end of December. When those periods were converted by the low accumulation hour below 5$^{\circ}C$, 900 hours were required approximately. This means that the rootstock needs for dormant breaking necessitates under the low temperature. In relationship between growing period and ABA content, the ABA in root-stock did not exist during maximum growing period, from April to September. This means that the ABA together with other substances in rootstock can be transferred to the shoot part with sprouting. While shoot part withered by decreacing the open field temperature since October, the ABA intiated to exist in rootstock. This means that the ABA in the shoot part can be transferred to the rootstock part. Therefore, it was concluded that the ABA which has been known that inhibiting growth and inducing dormancy was closely related with dormancy of rootstock.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.6
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• pp.425-438
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• 1990

Acoustic and ichthyoplankton data collected from Shelikof Strait in 1981, 1984 and 1985 were examined to determine spawning ground and period of walleye pollock, Theragra chalcogramma. Walleye pollock in the Gulf of Alaska migrated into Shelikof Strait for spawning during late winter and early spring. They entered Shelikof Strait via the warm and saline deep layer (continental slope water mass) in the southwestern channel, and major fish schools concentrated for spawning along the deep trough (250~300m) in the western part of the central strait. Peak spawning activity occurred there from late March to early April. Peak spawning time and area in Shelikof Strait varied little between years, despite difference in hydrography. Geographical advantages together with some oceanographic phenomena (reduced water transport and reduced mixed layer depth in spring) made that area an optimal spawning ground in the Gulf of Alaska during early April. After early April, spawning intensity decreased rapidly and the spawning area tended to expand to the northeast and southwest.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.6
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• pp.507-512
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• 1993

Pre-sowing treatments of tobacco seeds (cv. NC82) were evaluated as a means of improving the speed of emergence, early seedling growth and uniformity of the seedlings. Seeds were treated through the use of polyethylene glycol 6000(PEG), solid matrix priming(SMP), chilling and dark-preincubati(DPI). Under the laboratory condition of 15$^{\circ}C$, all the treated seeds germinated more rapid and the time to 50% germination(T50) reduced than control. Among the treatments, SMP was the best to reduce the T50 for germination. All the treatments did not affect the final germination percentage, while the chilling showed of little benefit for germination and T50. Under the greenhouse condition, seedling from SMP emerged earlier and more uniformity and also greater mean fresh and dry weight showed than other treatments. The advantage of T50 from SMP was affected more in temperature than in water content of Agro-Lig during the treatment.

• Current Research on Agriculture and Life Sciences
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• v.23
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• pp.1-8
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• 2005

The purpose of this study was carried out to determine the optimum sowing date and days after sowing (DAS) in automatic facility located at Uiseong of Gyeoungbuk province. The seedling height was rapidly increased with a delay of sowing time from April to May. The 10-day old seedlings with suitable plant height (> l0cm) for machine transplanting in the facility were obtained when the seeds sowed after May 20 at Uiseong in Gyeoungbuk province. The dry weight-height ratio of 10-day old seedlings was significantly decreased when the seeds sowed after June 20, and 15-days old seedlings did after May 10. No. of panicles/hill was reduced with increasing of days after seeding. But there were no significant difference among other yield components such as no. of grains/panicle, ratio of ripened grains, and 1,000 grain weight. The highest grain yield, 748kg/10a, was attained from the 10-day old seedlings transplanted at May 27 in comparision with those of 15-day and 20-day old seedlings. The grain yield of 10-day old seedlings transplanted at June 26 was also higher than that of 15-day old seedlings.

• Journal of KIISE:Computing Practices and Letters
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• v.16 no.4
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• pp.507-511
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• 2010

In this paper, we propose to enhance the performance of software transcoder by using GPGPU for scaling filters. Video transcoding is a technique that translates a video file to another video file that has a different coding algorithm and/or a different frame size. Its demand increases as more multimedia devices with different specification coexist in our daily life. Since transcoding is computationally intensive, a software transcoder that runs on a CPU takes long processing time. In this paper, we achieve significant speed-up by parallelizing the scaling filter using a GPGPU that can provide significantly large computation power. Through extensive experiments with various video scripts of different size and with various scaling filter options, it is verified that the enhanced transcoder could achieve 36% performance improvement in the default option, and up to 101% in a certain option.

• Journal of Sericultural and Entomological Science
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• v.47 no.2
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• pp.62-67
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• 2005

Much attention has been focused on the activity of the natural antioxidants present in fruits and vegetables, because potentially these components may reduce the level of oxidative stress. Especially, mulberry leaves containing many natural components are considerable resource far natural antioxidants. The antioxidant capacity of mulberry leaves was investigated with minilum L-100 device and ARAW-KIT (anti-radical ability of water-soluble substance), in comparison to the ascorbic acid. The appropriate conditions for pre-treatments of mulberry leaves were 80% MeOH, 30 sec. vortex mixing. The antioxidant capacity of 16 varieties was 3303.4 nmol (ascorbic acid equivalents) at opening stage of five leaves in spring. The highest stage of antioxidant capacity (3708.0 nmol) and yield rate was just before the coloration stare with anthocyanin in fruits, whereas the lowest stage was middle of June (2231.6 nmol) and about two months growing stage after summer pruning (2064.6 nmol). But after summer pruning, the antioxidant capacity of mulberry.