• Journal of Periodontal and Implant Science
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• v.25 no.3
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• pp.603-613
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• 1995

The purpose of this investigation was to evaluate on the biodegradability, biocompatibility and tissue regenerative capacity of synthetic bioabsorbable membranes in beagle dogs. For animal study, 9 adult beagle dogs were used to examination, on the surgical implantation of membranes and histological analysis. In each animal, the 3rd and 4th premolars of the both sides of the mandible were selected as test teeth. Two types of bioresorbable membranes including "Guidor membrane", "S-membranes" were used to examining for biological activity, and also Gore-tex membranes was used for positive control. Surgically created defects were made in 2 premolars of both sides of the mandible at $3{\times}4mm^2$ in size and tested membranes were implanted in the defected area. A plaque control regimen was instituted with daily tooth brushing with a 0.1% chlorhexidine digluconate during experimental periods. All the experimental animals were sacrificed after 2, 4, and 8 weeks from surgery and undecalcified slides were prepared using the "sawing and grinding" technique described by Donath and Breuner". In biodegradability, all the membranes were started their biodegradation from two weeks after implantation and gradually demolished of their frame morphology from eight weeks. However, demolition of membranes in 8 weeks after implantation was highest in Guidor membranes and followed by S-membranes. Biocompatibilityof two kinds of biodegradable membranes including Guidor and S-mambrane were shown to be well tolerated to the surrounding tissue, and were minimal accumulation of inflammatory cell infiltration around the implanted membranes to compare with Gore-tex membrane. Regeneration of defected alveolar bone was initiated from two weeks of membrane implantation and new bone formation was gradually increased from that time. However, pattern of new bone formation on the defected areas of two kinds of biodegrable membranes was almost similar and quite competitive comparing with Gore-tex membrane. These results implicate that bioresorbable membranes should be highly useful tool for guided tissue regeneration of periodontal defects.

• Journal of Bio-Environment Control
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• v.18 no.3
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• pp.258-265
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• 2009

This research was conducted to compare drymatter production and yield pattern between commercial glasshouse (G) and plastic greenhouse (PG) in Korea. In both greenhouses sawing and plating of sweet pepper was 28 August and 27 September, 2007. Destructive measurement and yield of sweet pepper, cv. 'Derby', was obtained from January to May, 2008. Averaged light transmissivity over 20 times observed 65% in G and 51 % in PG. The averaged daily radiation sum of greenhouses during whole growing period was $9.03MJ/m^2/day$ for G and $7.37MJ/m^2/day$ for PG Leaf area index (LAI) in G crop was 36% higher than the crop in PG at the end of experiment (247days after planting: DAP), whereas there was no significantly difference for 212 DAP in both greenhouses. Total dry matter production was $1759.9g{\cdot}m^{-2}$ for G and $1308.5g{\cdot}m^{-2}$ for PG Fruit production observed $14.1kg{\cdot}m^{-2}$ in G and $7.8kg{\cdot}m^{-2}$ in PG. There was slightly difference measurement of dry matter distribution of generative or vegetative parts to total dry matter between G and PG.

• Korean Journal of Soil Science and Fertilizer
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• v.36 no.6
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• pp.429-436
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• 2003

The relationship between seeding depth and apical hook opening was investigated in the hypocotyl hook of soybean (Glycine max Merr., cv. Hwanggeum). Seeds were sawn in different depths (2.5, 5.0, 7.5, and 10.0 cm). The hook opening was slowly progressed with seeding depth. Hook angle opening velocity was negatively correlated with hypocotyl growth at the significant level of P<0.01. It was also clearly observed that seeding depth was positively correlated with hypocotyl growth, suggesting the induction of hypocotyl growth by deep sawing. Futhermore, the contents of fructose and glucose in hypocotyls were about higher than in cotyledons. Both sugars in hypocotyls were highest at the emergence stage. After emergence, their levels were obviously reduced. Total soluble sugar contents continuously retained in cotyledons which were grown at 2.5 and 5.0 cm seeding depths whereas the contents in cotyledons of deep sawn soybean were extremely lowered. It seemed that sugars were actively used to cell construction during the hypocotyl elongation. The results demonstrated that apical hook opening is closely related with light signal after emergence. It implied that the delay of hook opening in deep sawn seeds was resulted from hypocotyl growth in darkness. We suggest that apical hook opening is progressed in sucrose catabolism by light.

• Journal of Bio-Environment Control
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• v.18 no.1
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• pp.74-80
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• 2009

This study was conducted to evaluate cultivation to save the production method cost of warm type garlic. The optimum system for producing excellent seed bulbs by using bulbils of garlic has been required. The bigger size bulbils induced fast growth and lower rate of non-cloved bulbs. The ratio of non-cloved bulbs was the highest in the 0.1 g bulbils sowing of 'Namdo' and was low in the big size bulbils sowing. The bulbil growth rate of 'Deaseo' was much faster than that of 'Namdo', but most of 'Deaseo' bulbils showed low rate of non-cloved bulbs and small size scales in bulbs. The higher productivities of "Namdo" bulbils appeared at the September 11th sowing time, but 'Deaseo' bulbils produced small size non-cloved bulbs and got the very low ratio of non-cloved bulb production in all of the treatment, sowing that Jeju Island could not produce the non-cloved bulbs with 'Deaseo' garlic bulbuls. The growth rate such as leave number, leave length, bulb and clove size in the sowing distance of big size bulbils increased as the sowing distance was wider, but the rate of non-cloved bulbils decreased regardless of treatment. More than 3 g clove in the $10{\times}15cm$ distance of bulbs was produced resulted in sowing clove production potentials by using big size bulbil.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.3
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• pp.303-309
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• 1989

Present study was conducted to reveal the effects of the herbicides, Lasso and Devrinol, on the soybean growth and the nodulation in field condition. Emergence rate was reduced positively in proportion to increase in the concentration of herbicides regardless of the herbicidal difference and it was significantly reduced even in the recommended concentration as compared to untreated plot, showing marked abnormal symptom on seedlings. Plant height, fresh weight of the plant, number of internodes, branches, pods, seeds per plant and 100-seed weight were reduced with increase in the concentration of herbicides and were highly significant in difference between the untreated plot and double concentration plot, eventhough most were nonsignificant in difference from the recommended concentration. Nodulation was significantly decreased with increase in the concentration of herbicides. The reduction was remarkably different with soybean varieties and consistently appeared from three weeks to six weeks after sawing. Significant correlation was realized between the reduction of nodulation and the agronomic characters of soybean and it was considered that the reduction of nodulation by misapplication of the herbicides might be a causal factor for decrease in soybean yield.

• Korean Chemical Engineering Research
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• v.50 no.2
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• pp.310-316
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• 2012

The chromaticity of polyethylene glycol (PEG) generated from the recyling of a silicone slurry waste was improved by using activated carbon powder and a carbon filter. The color change of the PEG waste was investigated by changing the amount of adsorbent, adsorption time and temperature. The surface area of activated carbon did not have a significant impact on improving the color of the PEG waste. According to the results for the APHA color variation of the PEG waste changing the amount of the carbon adsorbent, the optimal usage to achieve the low APHA value was 100~150 mg-C/g-PEG. From the investigatnion on the effect of the adsorption temperature range from $25^{\circ}C$ to $100^{\circ}C$, it was found that the optimal temperatures were $40{\sim}50^{\circ}C$ in terms of achieving the lowest APHA value. The variation of the APHA color was investigated by changing the operation condition of the activated carbon filters. The use of ACF was a good way to enhance the chromaticity of the PEG waste. As a result, the APHA value of the PEG waste (APHA=53 at the initial waste) was reduced to be 10 through the ACF purification. It was also confirmed that the performance of the used carbon adsorbent can be recovered by the washing with purified water.

• Korean Chemical Engineering Research
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• v.50 no.3
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• pp.567-573
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• 2012

Compared with the natural marble, the artificial marble has the advantages of excellent appearance, high degree of finish, even color, fine pressure and wear resistance, bear erosion and weathering, etc. It can be widely used in kitchen countertops, bath vanity tops, table tops, furniture, reception desks, etc. However, large amounts of artificial marble waste such as scraps or dust have been generated from sawing and polishing processes in artificial marble industry. Waste from artificial marble industry is increasing according to demand magnification of luxurious interior material. Artificial marble wastes can be recycled as aluminum oxide used as raw materials in electronic materials, ceramics production, etc., and methyl methacrylate(MMA) which become a raw material of artificial marble by pulverization, pyrolysis and distillation processes. The characteristics of artificial marble wastes was analyzed by using TGA/DSC and element analysis. Crude aluminum oxide was obtained from artificial marble waste by pulverization and thermal decomposition under nitrogen atmosphere. In this work, Box-Behnken design was used to optimize the pyrolysis process. The characteristics of crude aluminum oxide was evaluated by chromaticity analysis, element analysis, and surface area.

• Journal of Bio-Environment Control
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• v.20 no.4
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• pp.263-268
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• 2011

This study was carried out to investigate the effect of nursery period and block size on seedling quality and fruit yield of paprika (Capsicum annuum L. 'Cupra'). Seeds of paprika (Capsicum annuum L., Cupra) were sown in rockwool plugs. Seedlings were transferred and grown to the rockwool block different sizes: $5{\times}5$, $7.5{\times}7.5$ and $10{\times}10cm$ at sowing after 15 days. The plants were transplanted by 25, 30, 35, 40, 45 and 50 days we planted the seeds to the rockwool slabs. Seedling growth was not influenced by block size in the 25 day old plant, since then growed poorly with increasing nursery period in the $5{\times}5cm$ block size, plant height, stem diameter, fresh weight, dry weight have no difference from $10{\times}10cm$ and $7.5{\times}7.5cm$, but leaves and leaf area were higher $10{\times}10cm$ than the $7.5{\times}7.5cm$ block size. Growth of the paprika in field 80 days after sawing did not differ from nursery period and block size below 35 days old, but decreased with increasing nursery period and decreasing block size beyond 40 days old. Flowering did not differ from nursery period and block size below 35 days, but delayed with increasing nursery period and decreasing block size beyond 40 days old. The highest yield was obtained from 30 and 35 days old, and decreased with increasing nursery period and decreasing block size beyond 40 days old.

• Journal of the Korean Wood Science and Technology
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• v.48 no.1
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• pp.61-75
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• 2020

In this study, the environmentally friendly material charcoal was added to ricehusk, an agricultural by-product, and sawdust, which emerges during the sawing process, to produce board by mixing ratio and concentration levels of ricehusk and charcoal; it then investigated its physical properties for development purposes and achieved the following results. The water absorption and thickness swelling of the compounded board produced per adding ratio of ricehusk and charcoal showed a gradually decreasing tendency along with the increase in adding ratio of the charcoal, and as the density of the compounded board increased, the water absorption decreased, while the thickness swelling increased. The internal bond strength of the compounded board had indicated its highest value of 0.49N/㎟ at the density of 0.7g/㎤. This satisfied the quality standard for KSF 3104 Particleboard. The internal bond strength of the compounded board manufactured per adding ratio of ricehusk and charcoal showed a steady decrease with the decrease in the adding ratio of ricehusk, and an increase in the addingratio of the charcoal. Also, in cases when the ratio of the ricehusk and charcoal by KSF 3104 quality standard were 35:5 and 30:10, it satisfied the quality standard of 15.0-type, whereas it satisfied the 13.0-type quality standard if the ratios were 25:15 and 20:20. It showed a tendency of increasing hardness of the compounded board with the increase in density, and decreasing hardness with the increase in the adding ratio of the charcoal.

• Korean Journal of Breeding Science
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• v.43 no.3
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• pp.180-183
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• 2011

'Yeomyeong', a new welsh onion (Allium fistulosum L.) variety, is developed by the Bioenergy Crop Research Center, NICS, RDA in 2004. This variety, as interspecific $F_1$ hybrid, is developed by a cross between onion (Allium. cepa L.) and welsh onion (A. fistulosum L). The first cross was conducted in 2003 between MOS8, onion male sterile line and G2, welsh onion inbred line. Horticultural and yield characteristics of this hybrid $F_1$ line was investigated in greenhouse for 2 years from 2004 to 2005 with fall cropping cultivation. It has a single pseudostem plant type, anthocyanin-colored pseudostem, and male sterile umbel. It showed intermediate plant type of the maternal parents in overall plant characteristics. 'Yeomyeong' is fall sawing variety and has higher plant height and pseudostem length than that of check variety 'Gumjang'. The yield potential of this variety was about 130.1MT/ha in greenhouse in spring harvseting season. This variety would be adaptable to the fall sowing cultivation in green house.