• Plant Resources
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• v.2 no.2
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• pp.81-87
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• 1999

Sixteen isolates showing relatively strong antagonicity against the ginger rhizome rot pathogen, Pythium zingiberum, were selected among the 155 isolates from ginger rhizome surfaces and rhizospheres of ginger cultivation fields in Wanju, Chonbuk. The isolate, 'HB 26-5'showing the strongest antagonicity was finally selected by testing duration of inhibition effect and pathogenicity to ginger. The isolated antagonistic microorganism, 'HB 26-5' was rod shape, gram positive and formed endospore. The isolate produced acids utilizing glucose, arabinose, xylose and mannitol, and acetoin at VP test, and grew anaerobically. Temperature range for growth was from 10 to 4$0^{\circ}C$ . Reaction to catalase and gelatin, hydrolysis were positive, and casein hydrolysis and indol production were negative. Based on the mycological characters and the fatty acid composition, it was identified as Bacillus polymyxa. The pathogenicity test of isolated Bacillus polymyxa 'HB 26-5'on 22 crop cultivars resulted that only the lettuce was influenced in germination, and the others were not affected.

• Korean Journal of Optics and Photonics
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• v.18 no.5
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• pp.333-336
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• 2007

A Strained Layer Multiquantum-Well (SL-MQW) distributed feedback laser at a wavelength of 1.31 um operating from $-40^{\circ}C$ to $85^{\circ}C$ without any cooling is grown by metal-organic chemical vapor deposition (MOCVD). Lasers with high slope efficiency are achieved through careful optimization of a SL-MQW active layer, especiallyoptimizing the amount of strain, the well thickness, the barrier thickness, the number of wells, and the active layer width. In this paper, we obtain the slope efficiencies of 0.38[mW/mA] and 0.26 [mW/mA] at $25^{\circ}C$ and $85^{\circ}C$, respectively. Threshold currents are 7.1[mA] and 19.8[mA] at $25^{\circ}C$ and $85^{\circ}C$, respectively.

• Journal of Industrial Convergence
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• v.20 no.7
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• pp.1-11
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• 2022

In this paper, numerical values are derived using topic modeling among data-based evaluation methodologies discussed by various research institutes. In addition, we will focus on the ICT field to see if there is a difference in policy perception between the national R&D project and standing committee. First, we create model for classifying ICT documents by learning R&D project data using HAN model. And we perform LDA topic modeling analysis on ICT documents classified by applying the model, compare the distribution with the topics derived from the R&D project data and proceedings of standing committees. Specifically, a total of 26 topics were derived. Also, R&D project data had professionally topics, and the standing committee-discuss relatively social and popular issues. As the difference in perception can be numerically confirmed, it can be used as a basic study on indicators that can be used for future policy or project evaluation.

• Korean Journal of Medicinal Crop Science
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• v.2 no.3
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• pp.246-250
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• 1994

This study carried out to induce plant regeneration and callus formation from leaflet in MS medium with 2.4-D, NAL and IAA for in vitro growth of tuber, Kinetin and BA were used for plant regeneration. $NH_4NO_3$ and $KNO_3$ as a nitrogen source and $(NH_4)_2SO_4$, as a sulfate source were tested for in vitro growth of tuber. The resutls ars as fellows : 1. For the callus formation from leaflet and differentiation potency of organ, 2.4-D was more effective than IAA in MS medium under $26^{\circ}C$ and light condition of 8 hours a day. 2. For the plant regeneration from callus, MS medium with $2.0\;mg/{\ell}$ BA was most effective under $26^{\circ}C$ and light condition of $16{\sim}24$ hours a day. 3. For the in vitro growth of tuber, $KNO_3$ by $3.0g/{\ell}$ in MS medium was effective. This condition enhanced the growth of tuber 2.5 times compared with that in MS medium with $2.0\;mg/{\ell}$ BA.

• Journal of Embryo Transfer
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• v.20 no.3
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• pp.233-238
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• 2005

This study was carried out to investigate effects of claw trimming on reproductive efficiency in lactating cow. The results obtained were summarized as follows: 1. Days to 1st postpartum service were 180.9$\pm$47.2 days for control and 111.9$\pm$17.1 days for claw trimming. 2. Conception rate by 1st postpartum service was $25.0\%$ for control and $66.7\%$ for claw trimming. 3. Days to 1st postpartum conception were 258.1$\pm$43.3 days for control and 151.6$\pm$26.2 days for claw trimming(p<0.05). 4. Services per conception were 1.88$\pm$0.23 times for control and 1.44$\pm$0.18 times for claw trimming. 5. Calving interval was 489.3$\pm$47.2 days for control and 430.8$\pm$26.2 days for claw trimming.

• Journal of Astronomy and Space Sciences
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• v.26 no.4
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• pp.693-702
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• 2009

A computational fluid analysis was performed on an LOx line system of a liquid rocket engine. The model was created with 3D CAD and imbedded to the 3D CFD program. Before the full scale analysis on the system was carried out, each components with simplified models was analyzed to save time and cost. As a result, the inlet pressure of the gas generator should be compensated with a certain device unless the inlet pressure of the line system is sufficiently high. The flow pattern of the exit of the system was dependant upon the location of the orifice as well as the size. As a whole the line system analyzed met the requirements, and will be tested and confirmed after being manufactured.

• Journal of the Korean Chemical Society
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• v.26 no.5
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• pp.310-319
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• 1982

Cobalt(III) complexes with sexidentate ligands, N,N,N',N'-tetrakis(2-amino-ethyl)-1,2-ethanediamine (ten), -1,3-propanediamine (ttn), -1,4-butanediamine (ttmd), -(R,R)-and -(R,S)-2,4-pentanediamine (tptn) were prepared, and the characterization of d-d absorption band on the variation of chelate ring size and conformation of these complexes were studied by means of electronic spectra. The first d-d absorption bands of $[Co(L)]^{3+}$ complexes are shifted to smaller wave numbers in the order. ttn > (R,R)-tptn > ten > ttmd${\simeq}$(R,S)-tptn for (L). The UV, $^{13}C$ NMR, and Circular Dichroism studies indicate that the R,S-tptn ligand of $[Co(R,S-tptn)]^{3+}$ complex coodinates to cobalt(Ⅲ) ion as a sexidentate with one methyl group in axial position.

• Journal of Embryo Transfer
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• v.22 no.2
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• pp.111-114
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• 2007

This study was carried out to investigate the reproductive performance of average (less than 10,000 liters milk in 305 days) and high yielding (more than 10,000 liters milk in 305 days) Holstein cattle at commercial dairy herds (n=22). Data on milk progesterone (10 to 60 days postpartum), days to post-partum estrous, days to post-partum conception, service per conception and calving interval were recorded for two consecutive years. Post-partum milk progesterone concentration and days to reach peak milk progesterone concentration were similar in high and average yielding cows. High yielding cows took more days to show signs of first postpartum estrous than average yielding cows. Post-partum conception was 20 days earlier in average yielding cows than high yielding cows. Artificial insemination per conception was similar between average and high yielding cows. Calving interval was 26.9 days longer in high yielding cows compared to average yielding cows. In conclusion, better reproductive and feeding management may help improve the reproductive performance of high yielding dairy cattle in commercial dairy farms.

• Korean Journal of Ichthyology
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• v.22 no.3
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• pp.201-205
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• 2010

One specimen of a natural hybrid of an Oplegnathus (Oplegnathus fasciatus $\times$ Oplegnathus punctatus) was found in Tongyeong, Korea in August 2008. We, herein, describe its morphological and genetic characteristics and compare them with those of O. fasciatus and O. punctatus. In morphology, the hybrid showed many distinctive black rounded blotches on body sides and four faint vertical bars, being in those features similar to O. punctatus. Although the counts and measurements of the hybrid mostly overlapped between O. fasciatus and O. punctatus, the Oplegnathus hybrid resembled O. punctatus in the ratio of pelvic-fin length in standard length: Oplegnathus hybrid (26.7%) was closer to O. punctatus (26.4%) than to O. fasciatus (17.2~23.6%). In genetics, as a result of analysis of 510 base pair sequences of mitochondrial DNA 16S rRNA, the hybrid was closer to O. fasciatus (d=0.000~0.010) than to O. punctatus (d=0.020). Our results suggest that the natural hybridization represented by the subject specimen occurred between an O. fasciatus female and an O. punctatus male.

• The Korean Journal of Mycology
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• v.43 no.4
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• pp.267-271
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• 2015

Significant differences in annual precipitates on Jeju island have been reported depending on the location. We collected soil samples from east and west areas of Jeju Island to identify yeasts by plating on yeast peptone dextrose plates and subsequent analysis for the polymerase chain reaction amplified D1/D2 region of 26S rDNA of colonies. As a result, 20 yeast strains of 12 species were isolated from 7 different sampling sites in east area and 13 yeast strains of 6 species from 5 different sampling sites in west area. Some differences in yeast flora were observed depending on the sample collection sites having different annual precipitates.