• Horticultural Science & Technology
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• v.32 no.5
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• pp.673-683
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• 2014

This study was conducted to establish an efficient screening method to identify cucurbits resistant to powdery mildew. Powdery mildew fungus was obtained from a single lesion of infected cucumber leaf in 2010 at Daejeon. The fungus was identified as Podosphaera xanthii race 1 based on morphological characteristics and resistance responses of four melon differentials. Development of powdery mildew caused by the fungal isolate on 34 commercial cultivars of cucumber was investigated at three plant growth stages in a greenhouse. The degree of resistance of cotyledons of each cultivar to the fungus was not correlated with that of whole plant, but powdery mildew occurrence in the first true leaf was highly correlated with resistance at the level of the whole plant. Based on these results, the first true leaf of cucurbit cultivars can be used for screening of resistance to powdery mildew. In addition, variation of resistance of commercial 12 cucumber and 26 melon cultivars to the powdery mildew fungus due to different growing seasons was tested. In the case of cucumber, the resistance response in some cultivars was influenced by growing season. The resistant cultivars showed higher resistance in the warm season than in the cool season. By contrast, the resistant melon cultivars demonstrated strong resistance in all the tested growing seasons. Interestingly, the tested powdery mildew pathogen, a member of P. xanthii race 1, was not pathogenic on seven cultivars of watermelon (Citrullus lanatus). To follow up on this, diverse race 1 isolates of P. xanthii should be collected and tested.

• Korean journal of applied entomology
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• v.24 no.2 s.63
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• pp.97-101
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• 1985

Pathogenic variations of Xanthomonas campestris pv. oryzae were observed to Korean rice cultivars depending upon isolates in the same pathotype of the pathogen grouped by reactions of Japanese rice differentials. Using 201 Korean isolates of X. campestris pv oryzae 1,307 rice cultivars and promising lines were inoculated, and they were grouped into four varietal groups based on reactions. Of rice cultivars showing similar reactions to X. campestris pv. oryzae, five Korean rice cultivars Milyang 42, Hangangchalbyeo, Pungsanbyeo, Cheongcheongbyeo, and Milyang 23 were selected for classification of the pathogen into races The isolates only virulent to Milyang 23 were designated as race K1, the isolates virulent to Cheongcheongbyeo and Milyang 23 were designated as race K2, the isolates virulent to Pungsanbyeo, Cheongcheongbyeo and Milyang 23 were designated as race K3, the isolates virulent to Hangangchalbyeo, Pungsanbyeo, Cheongcheongbyeo and Milyang 23 were designated as race K4, and the isolates virulent to Milyang 42, Hangangchalbyeo, Pungsanbyeo, Cheongcheongbyeo and Milyang 23 were designated as race K5. Of 201 isolates tested, 114 isolates (56.7%) were classified as race K1, 47 isolates (23.4%) as race K2, 38 isolates (18.9%) as race K3, and 2 isolates (1.0%) as race K4. Reaction in each rice cultivar used as differentials in this test was also compared with that of rice differentials used for classification of X. campestris pv. oryzae into pathotypes in the previous work.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.5
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• pp.311-321
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• 2019

This study was conducted to investigate the relationship between motivation, stress and flow in bicycle race gambling. To accomplish this, data were collected from gambling users of a bicycle velodrome. A total of 347 samples were employed for analysis. The collected data were analyzed through multiple regression analysis. The results of the analysis were as follows. First, the level of flow increased as the motivation for participating in the contest increased. Second, the influence of the motivation to participate in the race on immersion showed that a higher motivation to participate in the race was associated with a higher level of stress. Third, verification of the motive for participating in the race and the mediated effect of immersion between stress revealed that immersion had a mediated effect on stress. Based on the results of these analyses, practical and policy implications were suggested. Accordingly, there is a need to identify the motivation for career participation in counseling of experienced gamblers. Moreover, it is important to establish a system to prevent excessive gambling flow.

• Restorative Dentistry and Endodontics
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• v.46 no.1
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• pp.13.1-13.9
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• 2021

Objectives: This study aimed to evaluate and compare the efficacy of the S1 reciprocating system and the D-Race retreatment rotary system for filling material removal and the apical extrusion of debris. Materials and Methods: Sixty-four freshly extracted maxillary canines were shaped with size 10 and size 15 K-files, instrumented using ProTaper Gold under irrigation with 2.5% sodium hypochlorite (NaOCl), obturated according to the principle of thermo-mechanical condensation with gutta-percha and zinc oxide eugenol sealer, and allowed to set for 3 weeks at 37℃. Subsequently, the teeth were divided into a control group (n = 4), the D-Race rotary instrument group (n = 30), and the S1 reciprocating instrument group (n = 30). After classical retreatment, the canals were subjected to a complementary approach with the XP-Endo Shaper. Desocclusol was used as a solvent, and irrigation with 2.5% NaOCl was performed. Each group was divided into subgroups according to the timing of radiographic readings. The images were imported into a software program to measure the remaining filling material, the apical extrusion, and the root canal space. The data were statistically analyzed using the Z-test and JASP graphics software. Results: No significant differences were found between the D-Race and S1 groups for primary retreatment; however, using a complementary cleaning method increased the removal of remnant filling (p < 0.05). Conclusions: Classical removal of canal filling material may not be sufficient for root canal disinfection, although a complementary finishing approach improved the results. Nevertheless, all systems left some debris and caused apical extrusion.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.6
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• pp.1449-1461
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• 2013

In this study, We analyzed whether the quality of marine leisure sports experience have effects on participants satisfaction, immersion and 5motive for reparticipation. We also investigated effect of participants' pre-experience of participating race on satisfaction, immersion and motive for reparticipation. Sense of freedom and social interaction appeared to affect satisfaction of participants significantly, but the sense of control did not. Sense of freedom had effect on immersion, whereas sense of control and social interaction had no effect on immersion. Significant relationship between motive for reparticiaption and participants' satisfaction and immersion was observed. Interaction effect between participant's satisfaction and was significant. Immersion mediates relation between reparticiaption and participants' satisfaction, participants experienced yahct race before showed more effect of satisfaction on motive for reparticiaption than participants with no race experience, who showed no significant effect of satisfaction on motive for reparticiaption. Immersion have effect on motive for reparicipation in both groups, but effect size was greater in the group with race experience. Thus, satisfaction and immersion of participants who have pre-experience of participating race showed greater effect on reparticipation than who haven't.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.4 no.3 s.8
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• pp.45-50
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• 2005

In this paper, a broadband single balanced mixer is presented using a wideband rat-race implementation by vertical coupling. Frequency is selected as $1.5{\sim}3$ GHz for RF, $1.64{\sim}3.14$ GHz for LO, and 140 MHz for IF signals. When LO signal with 6 dBm at 2.7 GHz is injected, a conversion loss of 7.5 dB and RF to LO isolation of 30 dB are obtained. Also, an average conversion loss of 10 dB, RF to LO isolation of 30 dB, and LO to IF isolation of 45 dB are obtained for frequency band of $1.5{\sim}3$ GHz.

• Korean journal of applied entomology
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• v.34 no.2
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• pp.83-88
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• 1995

Soybean has been cultivated in China for 5,000 years. The soybean cyst neamtode (SCN), Heterodra glycines, was recongnized in Northeastern China in 1899. Currently, it is known to occur in 12 provinces. The biology of SCN was investigated in several provinces. Six races of SCN were identified (race 1, 2, 3, 4, 5 and 7). About f10,000 soybean germplasm lines were evaluated for their resistance to race 1, 3, 4 and 5 of SCN. At least two black-seeded cultivars are resistant to all four races. Several tolerant soybean cultivars with yellow seed coat were released and are in production. Additional resistant cultivars are being developed. Nematicides were not applied in production Potential biocontrol agents and related aspects are being investigated.

• International Journal of Industrial Entomology and Biomaterials
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• v.8 no.1
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• pp.117-121
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• 2004

Soluble proteins of silkworm hemolymph were investigated by means of isoelectric focusing (IEF). The protein spectra during ontogenesis of races and inter-races hybrids kept in Bulgaria was studied. A total of 51 protein bands in the hemolymph from fourth larval instar to imago were ascertained. Stage specific expression was established. The specific expression of some protein bands in the individual spectra manifest phenotype of gene determinate polymorphism (HP F, HP J, HP K, HP L, HP Q - in the zone with pH gradient 3.5-6.2 and HP K, HP L, HP N, HP P, HP T - in the zone with pH gradient 9.5 - 6.2). Breed specific expression was observed. On the basis of the obtained results, it was established that the investigated breeds are heterogeneous and the isoelectric focusing method is successful when specifying the inner-race and inter-race polymorphism in silkworm.

• Journal of the Korean Society of Costume
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• v.51 no.5
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• pp.95-111
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• 2001

The purpose of this study is to analyze the costumes of the master in Yuantaizi(원대자) tumulus murals and to examine the relation to the costumes of Koguryo(고구려). The Master appeared in Yuantaizi Tumulus Murals wear Wuguan(무관), Pingshangze(평상장) and Pao(포) These costumes were used as chaofu(조복) by Han race(한족) at that time. It is believed that Yuantaizi tumulus belongs to a tomb of Qian Yan(전연). So we can conclude that Qian Yan accepted costume systems of Han race. And similar costumes appear in Tumulus Murals of Koguryo built around Pyungyang(평양) and Anak(안악) in 4∼5 century. Especially the master's costumes of Anak Tomb No.3(안악3호분) are nearly the same as Yuantaizi's. Maybe it is closely related to the fact that the master of Anak Tomb No.3 is Dongsu (동수) who defected from Qian Yan.

• Journal of Sericultural and Entomological Science
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• no.12
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• pp.17-20
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• 1970

Occasionally, We make mistake of discrimination of sex since a pair of small spots around tile abdomen of 9th abdominal of males and posterior spots of females of the silkworms larvae are found at almost same position. As already have reported, more larvae which have the small spots were found in Chinese race than the Japanese. This research has been conducted in order to grasp the rate of appearance of the small spotted larvae hereditarily when hybridize with different race (F$_1$) 1. According to the first report, average 17,8％ of the small spotted larvae are found in the Japanese race and 57.0％ in the Chinese, but my re-invested data which was carried out recently shows that average 13.6％ in the former case and 37.8％ in the latter. Those new data are supposed to be come to a conclusion that the figures are flexible but in any case high frequency of appearance of the larvae were found in the Chinese race than the Japanese (Reference Table 1 ) 2. Miscalculated ratio of the larvae from males to females are 1.2-2.6％, and from females to males are found 0.5％-0.9％ in the Japanese race, In case of the Chinese race, 7.1-9.4％ in tile former and 2.9-3.4％ in the latter. Those data also shows that more of the larvae found in Chinese race. 3. The larvae of small spotted and non-spotted are also seperated when hlybridize with different mating types and races. 4. More small spotted larvae are seen when hybridize with less appeared of the small spots of females and males which have the small spots than more appeared of the small spots of females with none spotted of the males (Reference Table 2. C.G.)B.F.). 5. More larvae of the small spots and found in case of hybridize in a group of having small spots than none of the spots (H>E). 6. With the exception of the case (A.B), in the same type of cross breeding (C.D, E.F, G,H), more larvae of the smal1 spots are also found in case of hybridize with males of having the spots than none of the spots.