• Elastomers and Composites
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• v.8 no.1
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• pp.33-51
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• 1973

We have studied the blending effects of Diene NF 35 R and Alfin 1530 at various blending ratios, 100/0, 70/30, 50/50, 30/70, 0/100, and of carbon black HAF-HS and ISAF-HS at various compounding ratios of 45 PHR, 55 PHR, 65 PHR, for tyre tread rubber. As the results, it was found that; 1. For tyre tread rubber, as the blending ratio, AR 1530/Diene NF 35R, indicated 70/30, the physical properties we examined were most excellent. 2. Excellent result was obtained in the case of carbon black compounding ratio of 55 PHR. The compounding of ISAF-HS made better result than that of HAF-HS for tensile strength, but the compounding of HAF-HS made better result than that of ISAF-HS for tearing strength and best result for abrasion quantity. 3. Heat buildup obtained from compounding carbon black HAF-HS indicated low temperature than that from compounding carbon black HAP-HS. As the compounding amount of carbon black increased, and as the blending amount of AR 1530 decreased, the heat buildup increased. 4. Carbon black was more efficient to AR 1630 than io Diene NF 35 R. 5. In the physical properties, mooney viscosity and mooney scorch time, as the compounding amount of carbon black increased, the values of mooney viscosity increased, but that of mooney scorch time had a max. point at the compoundiug amount of carbon black, 55 PHR.

• Journal of Plant Biotechnology
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• v.3 no.2
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• pp.95-100
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• 2001

To select the section with shoot formation ability, the calli and shoot formation from three sections (first leaf including cotyledonary node, hypocotyl and cotyledon explants) of 5-days-seedlings of soybean were induced on MS medium supplemented with 1.0 mg/L BAP, 3% sucrose, and 0.3% gelrite for one month. The first leaf section exhibited the highest shoot formation rate (51%), followed the hypocotyl section (10%) and the cotyledon section (0%). The shoot formation rates and shoot number of the four excised sections (whole first leaf, a half of the first leaf, a third of the first leaf and only node) of the first leaf were also investigated on the same medium. A half of the first leaf explant and the third of the first leaf explant had higher shoot formation rates (76-80%) and numbers (3-4 / explants) than those in other two explants. Effects of six cytokinins (kinetin, zeatin, BAP, 2iP, PBA, and TDZ) on shoot formation were determined, using the half of the first leaf explants. Zeatin (1.0 mg/L) exhibited the highest in shoot formation rate (94%) and numbers (8 / explant). In addition, the combined effects of three cytokinins (zeatin, BAP, and TDZ; 0.5, 1.0, 2.0 mg/L, respectively) and an auxin (IAA; 0.0, 0.5, 1.0, 2.0 mg/L) were determined. The combination (1:1, v/v) of zeatin (1.0 mg/L) and IAA (1.0 mg/L) exhibited the highest in shoot formation rate (96%) and numbers (16 / explant), twice more than zeatin (1.0 mg/L) alone. The shoot cuttings were transferred and cultivated on the rooting media supplemented with only auxin, IBA at various concentrations. The highest root formation (8 / shoot) was achieved on the medium supplemented with 1.5 mg/L. After 4 weeks of cultivation, the plantlets with an extensive root system were transplanted in pots with a soil mixture of vermiculite and fine sand. Transferred to field, about 75% of the plantlets survived.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.9
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• pp.1257-1263
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• 2010

The naval structure exposes to environmental vibration of shafted propeller propulsion and engine vibration. The shipboard equipments are developed compliance to MIL-STD-167-1A. For this purpose, vibration fatigue life of shipboard equipment for long lives should be estimate via an analytical approach and vibration test. In this paper, High cycle fatigue strength of cast aluminum alloy A356 using shipboard equipment was evaluated by 14 S-N method. The stress applied on the structure is evaluated by an analytical method(frequency response analysis with sinusoidal input and a fatigue evaluation) to simulate a MIL-STD-167-1A test. The frequency with the maximum equivalent stress is shown by Max. test frequency and the vibration fatigue life of shipboard equipment was estimated by Miner's rule.

• Journal of Microbiology
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• v.39 no.4
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• pp.305-313
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• 2001

The spr D gene encoding Strptomyces griseus protease D(SGPD); a chymotrypsin-like proteae, was cloned from Strptomyces griseus IFO13350 and sequence. Most of the amino-acid sequence deduced from the nucleotide sequence is idential to that Strptomyces griseus IMRU3499 except that one amino acid has been deleted and Trp 369 has been substituted into Cys369 in the SGPD from S. griseus IFO13350 without affecting the protease activity. The spr D gene was overexpressed in Streptomyce liv-idans TK24 as a heterologous host. Various media with different compositions were also used to max-imize the productivity of SGPD inthe heterologous host. The SGPD productivity was best when the transformant S. lividans TK24 was cultivated in R2YE medium. The relative chymotrypsin activity of the culture broth measured with an artificial chromogenic substrate, N-scuccinyl-ala-ala-pro-phe-p-nitroanilide, was 16 units/ml. A high level of SGPD was also produced in YEME and SAAM medial but it was relatively lower that in R2YE medium and negligible amounts of SGPD were produced in GYE, GAE and Benedict media. The growth of S. lividans reacted the maximum level of cell mass at days 3 and 4 of the culture, but SGPD production started in the stationary phase of cell growth and kept increase in till the 10$^{th}$ day of culture in R2YE and YEME medium, but in GYE media the productivity reached maximum level at 8days of cultivation. The introduction of the spr D gene into S. lividans TK24 triggered biosyntheis of the pigmented antibiotic , actinorhodin, which implies some protease may paly a very improtant role in secondary-metabolite formation in sStreptomyces.

• Journal of Magnetics
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• v.9 no.4
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• pp.101-104
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• 2004

The crystallization behaviours of nanocomposite made by a function of quenching rate (roller speed) were studied. The results showed that there was one step c$\mathbb{r}$ystallization process for the alloy quenched at roller speed of 32 m/s, which could be shown as, Am (amorphouse) + ${\alpha}-Fe/Nd_2Fe_{14}B$ ${\rightarrow}$ ${\alpha}-Fe/Nd_2Fe_{14}B$ . For the alloy quenched at roller speed of 40 m/s, there was steps crystallization process taking place at different temperatures, which could be shown as, Am ${\rightarrow}$ ${\alpha}-Fe/Nd_2Fe_{23}B_3+Nd_2Fe_{14}B+Am`$ ${\rightarrow}$ ${\alpha}-Fe/Nd_2Fe_{14}B$. The presence of transition phase ($Nd_2Fe_{23}B_3$) was harmful to get fine and uniform grain size during crystallization process. Uniform microstructures and high magnetic properties could be attained for the as-quenched alloy containing less amorphous phase and no presence of transition phase during annealing treatment. For the alloy prepared at roller speed of 32 m/s, the following properties were obtained, $B_r= 0.904 T,_iH_c = 801 kA/m, (BH)_{max} = 122 kJ/m^3 and M_r/M_s = 0.6$.

• Korean journal of applied entomology
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• v.14 no.4 s.25
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• pp.185-192
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• 1975

Various plant species, as many as 145 species in 43 families, were tested for susceptibility to the ordinary strain of the cucumber nosaic virus for two years from 1973 to 1974. Inoculations were made by mechanical method using carborundum. Plants in 71 species belonging to 27 families were infected. Of these species, systemic mosaic developed on the new leaves of plants in 57 species belonging to 24 families. Twenty-four species of plants, previously not reported as hosts of the CMV, were found to be infected in this experiment. These are Stellaria aquatica, Achyrauthes japonica, Agerratum houstonianum, Centipeda minima, Gillardia pulchella, Henisteptalyrate, Ixeris dentata, Saussurea uchiyamana, Brassica campestris, Lepidiumapetalum, Lobelia chinensis, Chenopodium bryoniaefolium, Carex neofilipes, Acalypha austalis, Amphicarpaea edgeworthii, Lotus corniculatus var japonicus, Phaseolus angularis, Sedum aizoom var heterodontum, Mosla punctulata, Perilla frutescens var japonica, Teucrium japonicum,. Linum usitatissimum, Mazus japonicus, Verbena hybrida. Twenty-three species reported to be susceptible by previous workers, but negative results were obtained in our experiment with Allium cepa, Celosia cristat, Daucus carota var. sativa, Artemisia asiatica, Callistenphus chinensis, Erigeron canadensis, Helianthusannuus, Tagetes eracta, Impatiens balsamina, Raphanus sativus, Ipomea batatas, Glycine max, Phaseolus vulgaris, Lilium longifolium, Papaver gomniferum, Sorghum vulgare, Triticum aestivum, Zea mays, Rumex coreanus, Potulaca grandiflora.

• Plant Resources
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• v.3 no.3
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• pp.184-193
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• 2000

Soybean [Glycine max (L.) Merr.] seed weight is a important trait in cultivar development. Objective of this study was to identify and confirm quantitative trait loci (QTLs) for seed weight variation in the F2 and F2:3 generations. QTLs for seed weight were identified in F2 and F2:3 generations using interval mapping (MapMaker/QTL) and single-factor analysis of variance (ANOVA). In the F2 plant generation (i.e., F3 seed), three markers, OPL9a, OPM7a, and OPAC12 were significantly (P<0.01) associated with seed weight QTLs. In the F2:3 plant row generation (i.e., F4 seed), five markers, OPA9a, OPG19, OPL9b, OPP11, and Sat_085 were significantly (P<0.01) associated with seed weight QTLs. Two markers, OPL9a and OPL9b were significantly (P<0.05) associated with seed weight QTLs in both generations. Two QTLs on USDA soybean linkage group C1 and R were identified in both F2 and F2:3 generations using interval mapping. The linkage group C1 QTL explained 16% of the variation in seed weight in both generations, and the linkage group R QTL explained 39% and 41% of the variation for F2 and F2:3 generation, respectively. The linkage group C2 QTL identified in F2:3 generation explained 14.9% of variation. Linkage groups C1, C2 and R had previously been identified as harbouring seed size QTLs. The consistency of QTLs across generations and populations indicates that marker-assisted selection is possible in a soybean breeding program.

• Journal of Pharmaceutical Investigation
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• v.32 no.1
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• pp.27-33
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• 2002

A self-microemulsifying drug delivery system(SMEDDS) composed of Cremophor $EL^{\circledR},\;Labrasol^{circledR}$, and Lauroglycol $FCC^{circledR}$ was prepared for the enhancement of solubility, dissolution rate and bioavailability of ibuprofen(IBP), which is water-insoluble but soluble in oils and surfactants. Phase diagram with various regions including microemulsion area was depicted. The SMEDDS was encapsulated in soft gelatin capsules and their dissolution characteristics in various media were observed in comparison to the generic products commercially available in the market. Soft capsules of SMEDDS formulation showed better dissolution profiles, especially in acidic condition, than the others. For the period of 1 hr dissolution in pH 1.2 medium, it reached over 70% dissolution from soft capsules, compared to less than 40% dissolution from commercial reference tablets. On the other hand, in vivo pharmacokinetic parameters were obtained after oral administrations of different IBP preparations to Sprague Dawley rats. SMEDDS formulation showed higher $C_{max}$ and greater $AUC_{0-5hr}$ than the suspension of reference tablet or IBP powder. Therefore, it is possible to conclude that a newly developed soft capsules employing SMEDDS provides an alternative preparation to improve oral bioavailability of IBP.

• The Korean Journal of Applied Statistics
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• v.6 no.2
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• pp.371-381
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• 1993

When the multicollinearity presents in the standard linear regression model, ridge regression might be used to mitigate the effects of collinearity. As the prediction-oriented criterion, the integrated mean sqare error criterion $J_w(k)$ was introduced by Lim, Choi & Park(1980). By noting the equivalent relationship between the $C_k$ criterion and $J_w(k)$ with a special choice of weight function $W(x)$, we propose a more reasonable selection rule of k w.r.t. the $C_k$ criterion than that given in Myers(1986). Next, to find the $\beta(k)$ which behaves reasonably well w.r.t. competing criteria, we adopt the minimax principle in the sense of maximizing the worst relative efficiency of k among competing criteria.

• Korean Journal of Remote Sensing
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• v.20 no.3
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• pp.175-188
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• 2004

The objectives of this study were to estimate leaf area index (LAI) as a function of image-derived vegetation indices, and to compare measured and estimated LAI to the results of crop model simulation. Soil moisture, crop phenology, and LAI data were obtained several times during the 2001 growing season at monitoring sites established in two central Missouri experimental fields, one planted to com (Zea mays L.) and the other planted to soybean (Glycine max L.). Hyper- and multi-spectral images at varying spatial. and spectral resolutions were acquired from both airborne and satellite platforms, and data were extracted to calculate standard vegetative indices (normalized difference vegetative index, NDVI; ratio vegetative index, RVI; and soil-adjusted vegetative index, SAVI). When comparing these three indices, regressions for measured LAI were of similar quality $(r^2$ =0.59 to 0.61 for com; $r^2$ =0.66 to 0.68 for soybean) in this single-year dataset. CERES(Crop Environment Resource Synthesis)-Maize and CROPGRO-Soybean models were calibrated to measured soil moisture and yield data and used to simulate LAI over the growing season. The CERES-Maize model over-predicted LAI at all corn monitoring sites. Simulated LAI from CROPGRO-Soybean was similar to observed and image-estimated LA! for most soybean monitoring sites. These results suggest crop growth model predictions might be improved by incorporating image-estimated LAI. Greater improvements might be expected with com than with soybean.