• Korean Journal of Medicinal Crop Science
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• v.4 no.2
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• pp.114-118
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• 1996

This experiment was carried out to investigate the effect of seeding date on the growth and yield of Cynanchum wilfordii. Hemsley emergence date was May 16 with seeding on March 20 and was June 4 with seeding on April 30, and required days to emergence was shortened as seeding date was delayed. Vine length was longer about 5cm with seeding on March 30 than that of seeding on march 20 and no. of leaves was small about 5 to 16 as seeding date was delayed. Root length was longer about 0. 9cm to 1. 8cm as seeding date was delayed than that of seeding on March 20, but no. of roots had no differences among seeding dates. Yield of root was more increased 18% with seeding on March 30, 10% with seeding on April 10 and April 20 than 207kg/10a with seeding on March 20. As the results of regression analysis, the optimum seeding date of Cynanchum wilfordii Hemsley was considered April 6 in plain area of central inland.

• Journal of The Korean Society of Grassland and Forage Science
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• v.4 no.1
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• pp.62-69
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• 1983

This experiment was carried out to find the effect of seeding rates and herbicides on the weed control, yield and crude protein of sorghum-sudangrass hybrid (Sorghum bicolor (L.) Moench). The variety used in the present study was Pioneer 988. Two different seeding rates were 25 kg/ha and 50 kg/ha and five weed control treatments were weedy check, hand weeded check, alachlor, alachlor+simazine, and simazine of preemergence application. The results of this study are summarized as follows: 1. Forage yield was not influenced by seeding rates. There was no significant difference between forage yield from 25 kg/ha and from 50 kg/ha of seeding rates. But weedy plots showed higher yield from the high seeding rate. Alachlor+simazine treatment showed the greatest yield among the weed control treatments. But there was no difference among the hand weeded treatment, simazine treatment, and alachlor+simazine treatment. 2. Seeding rates did not affect weed yield, but weedy plots showed the tendancy toward higher weed yield from the low seeding rate. Alachlor+simazing preemergence application showed the most effective weed control. But there was no significant difference in weed yield among the treatments of the hand weeded, alachlor+simazine and simazine. The weed yield in alachlor treatment was significantly higher than other three treatments. 3. The height of plant was shortest on the weedy plots and the longest height was obtained from the alachlor+simazine application. But in the first harvest the height was reduced by herbicides. Seeding rates did not affect the plant height. But the height was slightly taller under the low seeding rate than under the high seeding rate. 4. The percent crude protein of the forage did not affected by two seeding rates. Simazine treatments increased the percent crude protein and total crude protein yield. Simazine and alachlor+simazine application showed the significantly higher percent crude protein than hand weeded and alachlor treatments. Simazine increased the percent crude protein without reduction of forage yield. 5. Whereas the number of original stand was greater in the high seeding rate, the number of tillers per stand was higher in the low seeding rate. Weed reduced the number of stands and tillers. There was no significant indifference among the weed control treatments. It is concluded from above results that when sorghum-sudangrass hybrids are broadcasted for forage, 25 kg/ha rate of seeding is appropriate and alachlor+simazine treatment is most effective on weed control, maximum forage yield, and high percent crude protein.

• Korean Journal of Weed Science
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• v.15 no.1
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• pp.19-29
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• 1995

The effect of seeding depth on the growth, mesocotyl elongation and herbicidal response of rice(Oryza sativa L., Japonica type, cv. "Tongjin") and barnyardgrass(Echinochloa crus-galli Beauv. var orizicola Ohwi.) were studied in greenhouse experiments. Barnyardgrass growth as affected by different water depths was briefly tested. Rice and barnyardgrass were broadcast in soil into Oem, 1cm, 2cm and 3cm in seeding depth under dry direct-seeded condition. Butachlor(N-(buthoxymethyl)-2-chloro-N-(2,6-diethylphenyl) acetamide) at dose rate of 1800g ai/ha and thiobencarb(S-[(4-chlorophenyl)methyl] diethyl carbamothioate) at dose rate of 2100g and 4200g ai/ha were soil applied to them at 5 days after seeding. At 10 days after seeding, plants harvested to examine their growth as affected by seeding depth. Root length and shoot fresh weight of rice untreated was greatest in 1cm- and 3cm-seeding depth, respectively, however, mesocotyl did not elongate. While plant height of barnyardgrass grew regardless of seeding depth and water depth, but root length was greatest in 1cm-seeding depth of dry condition and reduced with increased water depth. And mesocotyl was elongated in only dry condition and its length increased with increased seeding depth. At 10 days after application thiobencarb applied pre-emergence inhibited plant height, and shoot fresh weight of rice in only 0cm-seeding depth under dry condition whereas was unaffected in above 1cm-seeding depth, similar to untreated control, and ever increased root length and root fresh weight of rice. On the other hand, shoot, root and leaf growth of barnyardgrass was, severely inhibited regardless of application rates and seeding depths. Reduction of shoot growth by treatment of herbicide was significantly greater than that of root growth. Consequently, reduction of barnyardgrass growth by treatment of thiobencarb did not be associated with seeding depth and mesocotyl elongation as affected by different seeding depth.

• Journal of Korea Foundry Society
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• v.26 no.4
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• pp.184-190
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• 2006

Presence of inclusions in Ti castings imparts detrimental effects on the mechanical performance of castings. However, actual inclusions do not occur very frequently and they are difficult to locate. As a result, acquirement of specimens for mechanical tests and thus in-depth research of the adverse influence of inclusions are challenging. To address this problem, artificial inclusion seeding methodology is developed to emulate actual inclusions in Ti investment castings. Firstly, to validate that this new methodology does not result in inherent mechanical property degradation, Ti specimens with machined, backfilled and HIPed holes are produced and compared to control (unaltered), cast Ti material. Fatigue test results indicate that this 'machine-and-HIP methodology without seeding' does not result in any fundamental mechanical property alteration, which would bias ensuing comparative results. Secondly, based on this result, validation of the artificially seeded inclusions being equivalent to 'as cast' inclusions is performed by comparing their fatigue behaviors. Test specimens created by the novel artificial inclusion seeding methodology are equivalent to Ti casting specimens containing actual cast-in inclusions, and an adverse effect of inclusions in investment castings is confirmed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.2
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• pp.223-229
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• 1996

To investigate the effect of seeding date, seeding rate, and sprouted seeds on seedling establishment, yield and its components of rice in barley /rice reley cropping as a minimum tillage, Gancheokbyeo rice seeds sowed by hand broadcast in various overlapped days befer barley harvest. The highest rice seedling stand was at sowed on the day just before barley harvest and l00kg per hectare of seeding rate with sprouted seeds. Also number of tiller and panicle showed the similar tendency. Delayed rice heading dates were found 2 days at l0-day overlap, 2 days at 5-day overlap, and 4 days at 0-day overlap before barley harvest compared with machine transplanting rice at just after barley harvest using l0-days old seedling. The culm length of broadcast rice shortened 2∼4cm compared with the transplanting rice. The rice plants lodged slightly at seeding rate l00kg per hectare and at sowed on the day of barley harvest. The rice panicle number increased with later date sowing and higher seeding rate. Number of spikelets per panicle and ripened grains decreased at higher seeding rates. Sprouted seeds and higher seeding rates showed higher rice yield at later sowing dates.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.3
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• pp.295-301
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• 1996

This study was carried out to clarify the effect of sprout length, burried depth of seed and CaO$_2$ seed coating on emergence, seedling stand and early growth of rice in puddled-soil drill seeding at Junbuk in 1995. The cultivar tested was Dongjinbyeo(Japonica type). Although the longer sprouted seeds were caused the better seedling stand, 4mm sprout length of seeds appeared to be appropriate for good seedling stand and seeding uniformity, while 6mm sprouted seed resulted in ununiform seedling establishment. Rapid emergence and increased seedling stand were obtained by CaO$_2$ seed coating, which had effect more on soaked seed than on sprouted seed, but the seedling stand of sprouted seeds significantly reduced at deeper than 1cm seeding depth and also emergence rate of sprouted seeds significantly reduced at deeper than 2cm seeding depth.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.445-451
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• 2013

We researched nitrogen and green manure yield of crotalaria by seeding rate; 50, 60, 70, 80, 90 kg $ha^{-1}$ in upland soil to find out crotalaria's optimal seeding rate. Crotalaria's plant height and number of leaves increased when the harvest time was later regardless of its seeding rate. Its nitrogen content of above-ground part was 19.8 g $ha^{-1}$, and C/N ratio was 22.5. The highest nitrogen content (50.3 g $ha^{-1}$) was found in flowers part, followed by its leaves, roots and stems. The green manure yields of crotalaria increased when the harvest time was later. The green manure yield of crotalaria was biggest in 50kg $ha^{-1}$ which was low in seeding rate. It tended to decrease when the seeding rate was higher, and the nitrogen yield had the same tendency. Therefore, the appropriate seeding rate was 50kg $ha^{-1}$ and the time for application to soil was considered to be the flowering stage.

• Korean Journal of Organic Agriculture
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• v.19 no.spc
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• pp.174-177
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• 2011

Green manure crops play an important role in organic farming. Field experiment was conducted at paddy soil (fine loamy, mixed, nonacid, mesic family of Aeric Fluvaquentic Endoquepts) in 2008/2009 to 2009/2010 at the National Institute of Crop Science (NICS), RDA, Suwon, Gyeonggi province, Korea. This experiment was carried out to evaluate the biomass of hairy vetch (Vicia villosa) and growth of rice (Oryza sativa) by different seeding rates. Seeding rates of hairy vetch consisted of 30, 60, and 90 kg $ha^{-1}$ by broadcasting before rice harvesting. The biomass and nitrogen production of hairy vetch were not significantly different between 60 kg $ha^{-1}$ and 90 kg $ha^{-1}$ of seedinq rates. Also, rice yield was not significantly different between seeding rate 60 kg $ha^{-1}$ of hairy vetch and conventional practice for two years. Therefore, we suggested that seeding rate of hairy vetch should be reduced by continuous cropping and incorporation of hairy vetch under rice-based cropping system.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.4
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• pp.378-383
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• 1997

Bird damages are often occurred at the seeding and seedling stages of crops. What the bird damage is preventing from the seeding and seedling of rice in the paddy would be very important to get high yield. Methiocarb was formulated as a bird repellent of crop seeding and seedling. Its effects on the seedling growth, related to the chemical injuries and the bird damages, were examined at the seeding and seedling growth stages of Anjungbyeo(Oryza sativa L.) with different types and amounts of methiocarb treatment in both pot and field experiments. In the pot experiment, bird damages were not occurred at all treatments of methiocarb, while bird damages were occurred at the control; 30, 85, and 100％ of damages at 5, 10, and 15 days after seeding, respectively. The ratio of seedling stand was not significantly different among all of treatments, methiocarb, methiocarb＋thiram, and control. However, the plant height and the number of seedling leaves at 15 days after seeding was shortened and lowered statistically more at treatment of methiocarb 15g than those of methiocarb 10g and control. The plant height at 35 days after seeding, showing the recovery degrees of chemical injuries, was significantly lowered in treatment of methiocarb＋thiram 15g, whereas the plant height of methiocarb FS 15g was not significantly differed from that of the control. In the field study, the bird damages were significantly reduced in treatment of methiocarb compared to that of the control. The plant height and the number of leaves at 25 days after seeding were not differed statistically among all of treatments. The chemical injuries were occurred in all treatments of methiocarb at 10 days after seeding, while they were not shown at 20 days after seeding.

• Korean Journal of Materials Research
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• v.6 no.7
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• pp.723-732
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• 1996

Cu films were deposited by chemical wapor deposition on the as-received substrates (TiN/Si) and three kinds of Cu-seeded substrates (Cu/TiN/Si) which had seeding layer in the thick ness of 5 ${\AA}$ and 130 ${\AA}$ coated by ICB(Ionized Cluster Beam) method. The effect of Cu seeding layers on the growth rate, crystallinity, grain size uniformity and film adhesion strength of final CVD-Cu films was investigated by scanning eletron microscopy(SEM), X-ray diffractometry and scratch test. The growth rate was found to incresase somewhat in the case of ICB-seeding. The XRD patterns of the Cu films on the as-received substrate and ICB Cu-seeded substrates exhibited the diffraction peaks corresponding to FCC phase, but the peak intensity ratio($I_{111}/I_{200}$) of Cu films deposited on the ICB Cu-seeded substrates increased compared with that of Cu films on the as-received substrate. The resistivity of final Cu film on 40 ${\AA}$ seeded substrate was observed as the lowest value, 2.42 $\mu\Omega\cdot$cm compared with other Cu films. In adhesion test, as the seeding thickness increased from zero to 130 ${\AA}$, the adhesion strength increased from 21N to 27N.