• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.1009-1020
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• 1996

Direct-seeded rice can have comparable yield with transplanted rice if its inherent problems can be solved. It is a labor-saving technology and can significantly reduce production cost because seedling nursery , pulling , and transplanting are omitted. Turnaround time between cropping is reduced hence the possibility of a third annual crop. But direct-seeded rice is very vulnerable to pest attack (by birds, rats, and golden snails), desiccation, weed infestation, and prone to lodging resulting to unstable crop establishment and inconsistent yield. These problems can be solved by anaerobic seeding (sowing pre-germinated seeds under the soil). It requires precise seed placement into the soil to optimize its benefits. We developed a four-row anaerobic direct seeder (US $ 200 commercial price) for this purpose . It consist of a structural framework mounted with a drum -hopper metering device, flotation type drivewheels, spring-loaded and adjustable furrow closers, and furrow open rs, and a plastic rainguard. It can sow in line pre-germinated seeds into the soil thus permitting the use of mechanical weeders for a chemical-free weed control. Its performance was comparable with the Japanese two-row anaerobic seeder (costing US$400) in terms of seed placement and crop establishment. It was tested with five cultivars. Seeding rate varied from 38 kg/ha to 80kg/ha. Crop establishment ranged from 64 to 99 percent while grain yield varied from 3.0 t/ha to 5.4t/ha. A six-row anaerobic seeder was also developed and adapted to a powertiller for increased capacity , field efficiency , and easier operation. The anaerobic seeder is useful to farmers shifting to direct seeding to reduce rice production cost and to researchers conducting agronomic studies in direct-seeded rice. Blueprint of the machine is available free of charge from IRRI.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.1
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• pp.41-47
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• 2012

The LDS(Laser Direct Structuring) is one of the new direct writing methods to fabricate conductive patterns by energy beam. It uses thermoplastic polymers with an additive compound that serves as plating seed after the activation by laser. The advantages of LDS include the miniaturization of electrical components, design flexibility, and a reduced number of production steps. The purpose of this study is to investigate the fundamental mechanism for LDS and the characteristics of conductive patterns by laser parameters. These results were studied by SEM, EDX, and XPS analysis. We have used a 20W pulse-modulated fiber laser and copper electroless plating to fabricate conductive patterns on polymer. The result showed that electroless copper plating seed caused the laser cracking of additive compound. In particular, the additive compound contained in copper metal oxides atoms will be changed to copper metal elements. Also, the characteristics of conductive patterns were dependent on laser parameter, especially laser fluence.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.3
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• pp.286-291
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• 1997

This experiment was carried out to improve seedling emergence and establishment in paddy rice sown into puddled soil. Rice seed were coated with CaO$_2$, KNO$_3$ and acid sulphate soil. When coated seeds with CaO$_2$, KNO$_3$ and acid sulphate soil were sown into puddled soil, soil redox potential was increased and the period of oxidizing was longer in KNO$_3$ than that of any other soils. pH was higher in control than that of coated seeds with CaO$_2$, KNO$_3$ and acid sulphate soil. It seems that the coated seeds oxidize soil locally, thus prohibit soil reduction. Seedling emergence was improved by seed coating materials. Emergence date was 8 days after seeding(DAS) in CaO$_2$, 14 DAS in acid sulphate soil, 21 DAS in KNO$_3$ coated seed and 20 DAS in uncoated seed, respectively. Emergence rate was highest in CaO$_2$ coated seed(80％) followed by acid sulphate soil coated seed(61％), while control(46％) and KNO$_3$(42％) were very poor. This result would be interpreted as the difference in oxidizing power among coating agents ; CaO$_2$ and acid sulphate soil may oxidize weakly and shortly while KNO$_3$ may oxidize soil strongly and persistantly. Our results suggested that local oxidizing around rice seed sown into puddled soil enhanced seedling emergence and also found a possibility to promote seedling emergence with acid soil.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.6
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• pp.429-433
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• 2001

This study was carried out to investigate the occurrence and characteristics of off-type rice plant according to agronomic conditions. The occurrence density of the off-type rice plant in farmer's paddy field was greater as the years of self-produced seed use increased, and in the direct sowing paddy field it was twice as much as in the transplanting paddy field. When the long-grain red rice and the short-grain red rice in the cultivated field of cultivar were artificially sown, in the direct sowing on a flooded paddy surface culture rather than in the machine transplanting culture the off-type rice plant occurred much more, the culm length was longer, and the number of productive culm per plant increased. These characteristics were more conspicuous in the long-grain red rice than in the short-grain red rice. In the transplanting farmer's paddy fields, the off-type rice plant that occurred outside of the hills of the cultivar rice ranged 0 to 6%. Whereas in was 70.6 to 91.9% when the long-grain red rice and short-grain red rice were artificially sown. Therefore, it was assumed that most of the off-type rice plants occurred in the farmer's paddy fields was caused by seed contamination.

• Journal of Periodontal and Implant Science
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• v.30 no.3
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• pp.553-569
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• 2000

Many natural medicines have been studied for their capacity and effects of antibacterial, anti-inflammatory and regenerative potential in periodontal tissues. Safflower seed has been traditionally used as a drug for treatment of bone fracture in oriental medicine. The purpose of the present study was to compare the effects of safflower seed extract and bone substitute on bone formation and regeneration in artificial defects in mongrel dogs. The bony defects were made with round bur at mandible and tibia. Extracts of safflower seed and bovine bone were placed directly at each defect for experimental group, and the defect of control group was sutured without any other treatment. Experimental animals were sacrificed at 8 weeks. And then histopathologic reading and histomorphometric study was done. There was not significant differences between control and experimental groups in osteoclastic activity and infiltration of inflammatory cells. However, new capillary proliferation, fibrosis and new bone formation were prominent in safflower seed extract group. The mandibular defects of safflower seed extract group were healed with dense connective and bony tissues, and endochondral bone formation was observed in tibial defect of safflower seed extract group only. New bone area of safflower seed extract group was more significantly increased than that of control and that of bone substitute group. These results indicate that direct local application of safflower seed extracts on bony defects seems to reduces the early inflammatory response and to promotes the bone regeneration.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.21
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• pp.9517-9522
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• 2014

Purple rice (Oryza sativa L. var. indica) cv. Kum Doisaket is cultivated in northern Thailand. This study evaluated the mutagenic and antimutagenic properties of hydrophilic and lipophilic components of purple rice using the Ames test. The seed and hull of purple rice were extracted with hexane, methanol, ethanol, and water. The methanol extracts had the highest amounts of phenolic acids and flavonoids, while the hexane extracts contained large amount of tocols and ${\gamma}$-oryzanol. None of the extracts were mutagenic in Salmonella typhimurium strains TA98 and TA100. The hexane extract of rice hull and the methanol extract of rice seed were strongly effective against aflatoxin B1- and 2-amino-3, 4 dimethylimidazo (4, 5-f) quinoline-induced mutagenesis, while aqueous extracts showed weakly antimutagenic properties. All extracts with the exception of aqueous extracts enhanced the number of revertant colonies from benzo (a) pyrene induced-mutagenesis. None of the extracts inhibited mutagenesis induced by the direct mutagens 2-(2-furyl)-3-(5-nitro-2-furyl)-acrylamide and sodium azide. The hull extracts showed more potent antimutagenicity than the seed extracts. Based on a chemical analysis, ${\gamma}$-oryzanol and ${\gamma}$-tocotrienol in the hull and cyanidin-3-glucoside and peonidin-3-glucoside in the seed are candidate antimutagens in purple rice. The antimutagenic mechanisms of purple rice might be related to either modulation of mutagen metabolizing enzymes or direct attack on electrophiles. These findings supported the use of Thai purple rice as a cancer chemopreventive agent.

• The Korean Journal of Ecology
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• v.19 no.4
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• pp.329-340
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• 1996

The extracts of selected plants and analyzed phenolic compounds were used to study the effects of alleloKDICicals on seed germination and seedling growth. HPLC analysis of the aqueous extracts of seven species identified 15 phenolic compounds including caffeic acid. Among them, protocatechuic acid was detected at 65.87ppm and 6.84ppm, in Erigeron canadensis and Pinus rigida, respectively. And the extract of P. rigida showed the strongest inhibitory effect on seed germination. The extract of P. rigida leaves significantly inhibited germination and radicle growth of Raphanus sativus var. hortensis for. acanthiformis in direct proportion to concentration. However, germination of Cassia mimosoides var. nomame was stimulated by the treated extracts at the same concentrations, but root growth was inhibited at high concentrations. Except chlorogenic acid, eleven of the twelve phenolic compounds inhibited the germination of R. sativus var. hortensis for. acanthiformis. In the case of C. mimosoides var. nomame, some phenolic compounds such as chlorogenic acid, vanillic acid, protocatechuic acid, ferulic acid, gallic acid and ${\rho}-coumaric$ acid stimulated germination, while the others reduced it.

• Journal of the Korean Society for Precision Engineering
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• v.27 no.10
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• pp.7-13
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• 2010

We report a hybrid DPSSL with a pulse parameter variable LD seed, all-fiberized polarization-maintained pulsed Yb-doped fiber preamplifier chains, and a bulk Nd:$YVO_4$ power amplifier. Pulse parameter of LD seed was controlled by direct current modulation. The hybrid DPSSL generates 1064 nm laser pulses with an average power of 40W, a pulse duration of 20-40ns, and a repetition rate of 100-500kHz.

• Journal of Ginseng Research
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• v.19 no.2
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• pp.171-174
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• 1995

Freshly harvested American ginseng (Panax quinquefolium L.) seeds were stratified at two locations over each of three years. Seed development and temperature in the stratification boxes were investigated until the seed was removed 12 months later and direct-seeded in the field. During stratification and seeding (14 months) three embryo stages were identified. In Stage I of 250 days (Sept. to mid-May) embryo length increased from about 0.5 to 1.0 mm: in Stage II of 100 days (mid-May to late Aug. when seeded) length increased to 2.0 mm and in Stage III (late Aug. to late Nov.) length increased to 5.3 mm. Excerpt split width could also be placed in three stages. Changes in embryo length correlated with embryo endosperm length ratio. Insertion compression tests showed that the excerpt softened rapidly in late Stage II and throughout Stage III. The stratification box temperatures at all depths (10, 25 and 50 cm) never exceeded -2$^{\circ}C$ even when the air temperatures dropped to -13$^{\circ}C$ and were, therefore not damaging to the seeds.

• Korean Journal of Plant Resources
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• v.14 no.1
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• pp.38-42
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• 2001

This study was conducted to stable direct sowing cultivation with seedling growth promotion by plant growth regulator treatment in onion seed(Allium cepa L.) The emergence percentage of soaked seed in BA, GA$_3$, and kinetin solution were higher than control seed, and those were 93.0, 94.3, 93.8%, respectively. The plant height was significant elongation in growth regulators treated seed, and those effects were high GA$_3$, kinetin and BA in the order, and the extend were high as increasing the growth regulator solution concentration in GA$_3$ and BA, and that was reverse in kinetin. The No. of leaf was increased in growth regulators treated seed, and the extend were similar among the growth regulators. The No. of root was increased significantly in growth regulators treated seed, and the extend were high in GA$_3$, BA and kinetin in the order.