• Korean Journal of Weed Science
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• v.12 no.1
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• pp.16-30
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• 1992

A field experiment was done to evaluate the growth response, rhizobia nodulation and vesicular-arbuscular mycorrhizal fungi (VAMF) infection of soybean treated with the different concentration of three-herbicides, alachlor, simazine, linuron. The results obtained were summarized as follows ; Emergence rate of soybean was non-significantly decreased by increasing the herbicide concentration. In simazine treatment, low emergence rate showed even in recommended concentration, especially the lowest emergence rate in treble concentration of recommended dose was about 50%. The plant length of soybean lowered by increasing the herbicide concentration, but there were almost no differences in recommended dose. Particularly that in a high concentration of herbicides at three weeks after treatment(WAT) was decreased remarkably. In the plant diameter of soybean shoot, no differences in the recommended concentration of alachlor and linuron at 2 WAT, but those of recommended dose was decreased with the lapse of time, and the lowest treatment was simazine-treated plot. Leaf area and fresh weight of soybean tended to decrease over the control even in recommended concentration and it was decreased with the increment of the herbicide dose. Yield component, fresh weight of rhizobia nodule and chlorophyll content of soybean leaves were reduced with the increment of herbicide dose, espicially remarkable tendency was revealed in simazine-treated plot. Seasonal infection rate of VAM showed a slight decrease by increasing of herbicide dose, and the lowest infection was simazine treatment. Significant correlation was realized among the reduction of rhizobia nodulation, VAM colonization and the agronomic characters of soybean and it was considered that the reduction of rhizobia nodulation and VAM colonization by misapplication of the herbicides might be a causal factor for decrease in soybean yield.

• Polymer(Korea)
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• v.38 no.2
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• pp.225-231
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• 2014

The rheological properties of highly concentrated polymer bonded explosive simulant were studied by using poly(ethylene-co-vinyl acetate) with 30 and 60% vinyl acetate (VA) content as a binder, respectively. Calcium carbonate and Dechlorane, whose physical properties are similar to resarch department explosive (RDX)'s, were used as fillers. The suspensions were mixed in a batch melt mixer and it was possible to fill 75 v% at maximum. From dynamic mechanical analysis, Dechlorane showed higher interaction with binder resins than that with calcium carbonate fillers. The effects of microstructural change on the rheological properties of the suspensions were investigated by a plate-plate rheometer with constant shear rate and constant shear stress modes, respectively. The theoretical maximum packing fraction of EVA31/Dechlorane suspension obtained from Krieger-Dougherty equation was 70 v% and it was thought that 2000 Pa was proper shear stress condition for this melt processing.

• Proceedings of the KIEE Conference
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• 2006.10a
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• pp.28-29
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• 2006

To improve Mechanical and Thermal Properties of semiconducting materials in power cable, we have investigated those of semiconducting materials showed by changing the content of carbon black and Carbon Nanotube. Density were measured by EW-200SG. High temperature, heat degradation initiation temperature, and heat weight loss were measured by TGA (Thermogravimetric Analysis). The dimension of measurement temperature was $0[^{\circ}C]$ J to $700[^{\circ}C]$, and rising temperature was $10[^{\circ}C/min]$. Heat degradation initiation temperature from the TGA results was decreased according to increasing the content of Carbon Nanotube. That is, heat stabilities of EVA containing the weak VA (vinyl acetate) against heat was measured the lowest. From the results of the experiment applied in this study, it is evident that a small amount of Carbon nanotube additives significantly improved the Mechanical and Thermal Properties of semiconducting materials.

• Journal of The Korean Society of Grassland and Forage Science
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• v.23 no.3
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• pp.211-218
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• 2003

This study was conducted to select the promising varieties of timothy (va.) Climax, Itasca, Alma, Comtal, Liphlea, Erecta, Argus and Kunpu at Daekwanryong(altitude 800m a.s.l.) and Namwon(altitude 450m a.s.l.) branch, and orchard grass (va.) Potomac, Warrior, Ambassador, Hapsung 2, 20, 93E and Kitamidori at Daekwanryong branch of National Livestock Research Institute, from 1999 to 2002. Among the timothy varieties, leafness of Liphlea, Erecta and Kunpu was greatest. Heading time of Liphlea and Kunpu was earliest and plant length of Kunpu was longest. Also, winter survival of Erecta and Kunpu was greatest with 94.0%. Among the orchardgrass varieties, although heading time of Hapsung 20 was late, it's leafness was the best and plant length was the longest in all varieties. Also, winter survival of Hapsung 20 was the highest in all varieties. In Daekwanryong and Namwon, dry matter yield of timothy(va.), Kunpu was highest(P<0.05) among the timothy varieties with 9,493kg and 13,890kg/ha, respectively. Dry matter yields of orchardgrass(va.), Hapsung 2 and Hapsung 20 were greatest among the varieties with 8,690kg and 8,818kg/ha, respectively. In two areas, average ADF concentration of Climax was lowest with 33.4%, and NDF concentration of Argus was lowest with 65.4% in all varieties. Average crude protein content of Alma was the highest with 16.5% and that of Kunpu was the lowest with 13.9%. Average crude protein yield of Kunpu was the highest with 1,710.5kg/ha in all timothy varieties. The ADF concentration of Hapsung 20 was lowest (33.4%), and NDF concentration of 93E was lowest (67.5%). Crude protein content (13.5%) and crude protein yield (1,173.2kg/ha) of Hapsung 2 were highest. These results indicate that Kunpu and Liphlea would be the promising varieties of timothy in Daekwanryong and Namwon, and also, Hapsung 2 of orchardgrass would be the promising varieties in Daekwanryong.

• Korean Journal of Veterinary Service
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• v.33 no.4
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• pp.375-385
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• 2010

An investigation was conducted to evaluate the effects of supplementing Alisma canaliculatum, Viscum album and Cornus officinalis probiotics on the growth performance and immune response in growing pigs. This experiment was conducted using 120 pigs (crossing of Landrace${\times}$Yorkshire and castrated) which were assigned to 5 treatments in 3 replications with 8 pigs per replications. The dietary treatments were NC group (without antibiotics), PC group (basal+Oxytetracycline 50ppm), AC group (basal+A. canaliculatum 0.5%), VA group (basal+V. album 0.5%) and COP group (basal+C. officinalis probiotics 0.5%). The initial body weights of pigs were 35kg on average and the experiment lasted for 9 weeks. The experimental animals were kept in the pens following a completely randomized design. They were provided the diets adequate for grower stage as recommended by NRC (ME:3,265 kcal/kg and CP:16%). COP fed pigs showed lower weight gain up to 6 weeks of age compared to NC group and other groups without significant differences (P>0.05). The carcass weights of pigs fed VA and COP were significantly higher compared to NC group (P<0.05), Back fat thicknesses groups fed three different additives were higher than NC group and lower then PC group (P<0.05). Crude fat contents in loin meat were significantly lower in groups fed three different additives while moisture contents of those three groups were higher than other groups (P<0.05). The thiobarbituric acid reaction substance (TBARS) value measured at fresh and $2^{nd}$ weeks was lower in additives fed groups but no statistical differences were observed among the treatments (P>0.05). Significantly highest PUFA (16.42g/100g) and ${\omega}$-3 fatty acids (ALA, EPA and DHA) content of meat were observed in COP fed pigs compared to NC group (P>0.05), which might mean that three additives function to enhance serum IgG in pigs. In consequence, it can be suggested that AC, VA and COP may have a potential to replace antibiotics as growth promoter and immune enhancer in the diets for growing pigs.

• Journal of The Korean Astronomical Society
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• v.38 no.2
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• pp.85-88
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• 2005

Construction of the Virtual Observatory (VO) is a great concern to the astronomical community in the 21st century. We present an outline of the concept and necessity of the va and the current status of various VO projects including the 15 national ones and the International Virtual Observatory Alliance (IVOA). We summarize the possible science cases that could be solved by using the VO data/tools, real science cases which are the results of using current VO tools, and our own work of using AstroGrid, the United Kingdom national VO, for a research on star formation history of galaxies.

• Journal of the Korean Society of Tobacco Science
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• v.17 no.1
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• pp.57-61
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• 1995

Black shank(Phytophthora parasitira roar. nicotianae) resistant burley tobacco (Nicotiana tabacum L.) germplasms, KB 104 and KB 106, were developed by Korea Ginseng & Tobacco Research Institute. KB 104 was developed from the single cross of Burley 21$\times$Newton 77, using a modified pedigree method. KB 104 was highly resistant to black shank, and its agronomic characteristics and chemical contents were comparable to those of Burley 21, and value per 10a was slightly higher than Burley 21, KB 106 is a maternally derived doubled haploid made by N. africana method from the single cross of Burley 21$\times$ Va 509. KB 106 was also highly resistant to black shank, had two more harvestable leaves per plant and flowered three days later than Burley 21 did. Total alkaloid and nicotine contents of KB 106 were significantly lower than those of Burley 21. But its nornicotine content was higher than Burley 21 5. Key wads : Burley tobacco germplasm, Black shank resistance.

• Biomolecules & Therapeutics
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• v.23 no.6
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• pp.525-530
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• 2015

Ceramide is the most abundant lipid in the epidermis and plays a critical role in maintaining epidermal barrier function. Overall ceramide content in keratinocyte increases in parallel with differentiation, which is initiated by supplementation of calcium and/or vitamin C. However, the role of metabolic enzymes responsible for ceramide generation in response to vitamin C is still unclear. Here, we investigated whether vitamin C alters epidermal ceramide content by regulating the expression and/or activity of its metabolic enzymes. When human keratinocytes were grown in 1.2 mM calcium with vitamin C ($50{\mu}g/ml$) for 11 days, bulk ceramide content significantly increased in conjunction with terminal differentiation of keratinocytes as compared to vehicle controls (1.2 mM calcium alone). Synthesis of the ceramide fractions was enhanced by increased de novo ceramide synthesis pathway via serine palmitoyltransferase and ceramide synthase activations. Moreover, sphingosine-1-phosphate (S1P) hydrolysis pathway by action of S1P phosphatase was also stimulated by vitamin C supplementation, contributing, in part, to enhanced ceramide production. However, activity of sphingomyelinase, a hydrolase enzyme that converts sphingomyelin to ceramide, remained unaltered. Taken together, we demonstrate that vitamin C stimulates ceramide production in keratinocytes by modulating ceramide metabolicrelated enzymes, and as a result, could improve overall epidermal barrier function.

• The Transactions of the Korean Institute of Power Electronics
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• v.10 no.3
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• pp.233-240
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• 2005

In this paper, AC electric vehicle propulsion system(Converter/Inverter) using high power semiconductor, IPM is proposed. 2-Parallel operation of two PWM converter is adopted for increasing capacity of system and the harmonic content is eliminated by the phase shaft between two PWM converters switching phase. VVVF inverter control is used a mixed control algorithm, where the vector control strategy at low speed region and slip-frequency control strategy at high speed region. The proposed propulsion system is verified by experimental results with a 1,350kW converter and 1,100kVA inverter with four 210kW traction motors.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.5
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• pp.663-670
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• 2008

The effect of supplementing the diet of grazing dairy cows with fish oil (FO) and linseed oil (LSO) on milk conjugated linoleic acid (CLA) was investigated. Sixteen Holstein cows (17019 DIM) were assigned into two groups and fed a grain supplement (8.0 kg/d; DM basis) containing 800 g of saturated animal fat (CONT) or 200 g FO and 600 g LSO (FOLSO). All cows grazed together on Sudan grass pasture ad libitum and were fed the treatment diets for 3 wks. Cows were milked twice a day and milk samples were collected during the last three days of the trial. Milk production (24.89 and 22.45 kg/d), milk protein percentage (2.76 and 2.82) and milk protein yield (0.68 and 0.64 kg/d) for the CONT and FOLSO diets, respectively, were not affected (p>0.05) by treatment diets. Milk fat percentage (3.90 and 2.86) and milk fat yield (0.97 and 0.64 kg/d) were lower (p<0.05) with the FOLSO diet compared with the CONT diet. The concentration and yield of milk cis-9 trans-11 CLA were higher (p<0.05) with the FOLSO diet (2.56% of total FA and 16.44 g/d, respectively) than the CONT diet (0.66% of total FA and 6.44 g/d, respectively). The concentrations of milk trans C18:1 and vaccenic acid (VA) were higher (p<0.05) with the FOLSO diet (13.53 and 7.48% of total FA, respectively) than the CONT diet (3.69 and 2.27% of total FA, respectively). In conclusion, supplementing the diet of grazing cows with FO and LSO increased milk cis-9 trans-11 CLA content but reduced milk fat content and yield.