• Korean journal of applied entomology
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• v.52 no.4
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• pp.415-425
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• 2013

The yellow tea thrips, Scirtothrips dorsalis (Thysanoptera: Thripidae), has been regarded as a minor pest on citrus on Jeju Island. However, the damage of yellow tea thrips has gradually increased since 2007. This study was conducted to develop a forecasting model for generation peak time of S. dorsalis by using degree-days. Simple linear regression analysis was applied to determine the relationship between the generation number (x, dependent variable) and degree-days (y, independent variable). As a result, two regression models were established: citrus-based model (y = 310.9x + 69.0, $r^2$=0.99) and green tea-based model (y = 285.7x + 84.1, $r^2$=0.99). The models was fitted by independent data sets obtained from 2013 and evaluated using the technique of RSS (residual sum of square) and ${\chi}^2$-test. The green tea based-model showed a good fitting ability. The discrepancy between model outputs and actual data, and the practical application of models were discussed.

• Journal of Embryo Transfer
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• v.31 no.3
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• pp.243-247
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• 2016

Growth traits, such as body weight, directly influence productivity and economic efficiency in the swine industry. In this study, we estimate heritability for body weight traits usinginformation from pedigree and genome-wide single nucleotide polymorphism (SNP) chip data. Four body weight phenotypes were measured in 1,105 $F_2$ progeny from an intercross between Landrace and Jeju native black pigs. All experimental animals were subjected to genotypic analysis using PorcineSNP60K BeadChip platform, and 39,992 autosomal SNP markers filtered by quality control criteria were used to construct genomic relationship matrix for heritability estimation. Restricted maximum likelihood estimates of heritability were obtained using both genomic- and pedigree- relationship matrix in a linear mixed model. The heritability estimates using SNP information were smaller (0.36-0.55) than those which were estimated using pedigree information (0.62-0.97). To investigate effect of common environment, such as maternal effect, on heritability estimation, we included maternal effect as an additional random effect term in the linear mixed model analysis. We detected substantial proportions of phenotypic variance components were explained by maternal effect. And the heritability estimates using both pedigree and SNP information were decreased. Therefore, heritability estimates must be interpreted cautiously when there are obvious common environmental variance components.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.4
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• pp.611-619
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• 2018

Basalt powder sludge (abbreviated BPS) is an inevitable industry by product resulted from the stone processing. Recently, demands for natural materials have been increasing in the construction and landscaping fields, therefore, amounts of BPS have been also increasing. Since most of BPS are used as landfill and earth soil, it is necessary to figure out to expedite their utilization. In this study, by considering the characteristics of precipitation of Jeju, effectiveness of BPS as a filler for asphalt compounds mixed with cement were analyzed. As a result, BPS satisfies quality criterion required in KS F 3501. Marshall mixing designs were performed to determine the optimal asphalt content for the Modified recycling asphalt mixture (27% recycling aggregate) and the Normal asphalt mixture. Effectiveness of BPS were identified by the Marshall Stability Test with the mixing ratio (level 3) of two asphalt compounds and composition ration (level 3) of BPS and cement. Performance of asphalt compounds shown appropriate effect of mixing and composition ratios of the filler were assessed. Test results show that two types of asphalt compounds satisfy the quality standards of the MLIT (2015). Therefore, BPS could be used as filler for asphalt compounds.

• Journal of The Korean Society of Grassland and Forage Science
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• v.35 no.2
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• pp.93-98
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• 2015

This study was conducted to investigate the effect of different stockpiled periods on the nutritive value and productivity of mixed orchardgrass tall-fescue pasture (MOTP). This experiment was conducted at Jeju (island), South Korea, from Sep. 2012 to Nov. 2012. The DM yield of the MOTP had the highest in treatment in late August (2,983 kg/ha). The DM yields of swards were increased significantly by shortening the stockpiled period. The CP of the MOTP was 16.5% to 18.16%, and there did not appear to be a consistent trend in accordance with the duration of the stockpiled periods. The NDF and TDN content of the MOTP increased with the delay of the stockpiled periods, but there is a significant difference between the short- and long-stockpile periods; however, the ADF content of the MOTP decreased with shortened stockpile periods, but again, there is a significant difference between the two periods. In addition, P, Ca, Mg, Na, and Zn of MOTP increased by delaying the stockpile period, but Mn and Cu of MOTP decreased. As shown in the results of this research, the yield of MOTP was not increased by the atrophy of the growth of MOTP due to high temperatures in case where the MOTP was stockpiled from the beginning of August. The stockpile period of MOTP should therefore be started at the end of August to yield a stockpile of MOTP in the autumn.

• Journal of the Economic Geographical Society of Korea
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• v.9 no.1
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• pp.97-122
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• 2006

The purpose of this paper is to analyze production and innovation networks of services in the long-live area of Gangwon and Jeju Provinces and to suggest a policy direction for regional development of rural areas where have been neglected in the knowledge-based information society. Four counties in the Honam Region, the long-live belt of Korea and two cities (Jeonju, Gwangju) are surveyed for the purpose of comparison with the Gangwon and Jeju areas. Production and innovation networks of research and supporting activities and tourist services are analyzed based on intensive interview surveys of the regions. The result of the analysis suggests that the innovation networks among the economic actors have considerable impacts on the innovation processes of the service activities and the service functions in the rural area are somewhat developed with local industry after the practice of local autonomy. The processes of innovation networks are progressed differently by the hierarchy of the regions as well as by the function of services such as research and supporting activities and tourist services. The direction of the rural development in the knowledge-based information society seems to be intensifying the networks among the innovative actors and developing virtual innovation networks for the development of rural innovation systems.

• Korean Journal of Plant Taxonomy
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• v.43 no.4
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• pp.319-331
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• 2013

Records found on labels of specimens deposited at Kyoto University (KYO) and references about three Japanese taxonomists, Koidzumi, Gen'ichi (1883-1953), Ohwi, Jisaburo (1905-1977), Kitamura, Siro (1906-2002) were assembled to produce collector's itineraries from 1930 to 1935 in Korea. The quality of data on labels of the specimens varies, but most are only the collector's name and country of collection, often, the locality data are only textual, and the Chinese and Japanese names, as well as the ethnic dialects common to the region, varies widely. It is estimated that approximately 2,000 specimens collected from Korea by three taxonomists are currently held within the collections of Kyoto University herbarium (KYO). Koidzumi, who was the professor of Kyoto University, traversed different northern parts of the country, such as Island Jeju-do, Mt. Keumkang-san, Hamkyongbuk-do during summer (July to August) in 1932, 1933, and 1935. In 1930 and 1932, Ohwi spend three months in the unexplored mountains in northern parts, such as Hamkyeongnam-do, Hamkyeongbuk-do, and Gangwon-do. On the other hand, for two months in the middle of 1935 visited Jeju-do, Mt. Jirisan and travelled through southern parts. Unlike two previous botanists, major collections in Korea by Kitamura took place twice in one major area in northern part and Jeju-do and Mt. Keumgang-san in 1930, 1932, and 1935.

• The Korea Journal of Herbology
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• v.30 no.1
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• pp.43-49
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• 2015

Objectives : In this study, the anti-stress effects of ethanolic extract of Opuntiaficus-indica (OF70E) were investigated. Methods : To determine the effects of OF70E on physical stress, changes in whole-body cortisol level or behavior were monitored in zebrafish. After treatment with 0.9% saline or OF70E for 6 min, all fish underwent net handling stress (NHS), which induced physical stress. And then, we conducted open field test (OFT) or sacrificed fish for collecting body fluid from whole-body. We used the cortisol enzyme-linked immunoassay kit to measure the amount of cortisol in each zebrafish sample. Results : In result, compared with normal group which were not treated by NHS, whole-body cortisol levels were significantly increased in stressed-control group. Compared with control group, pretreatment with OF70E at concentrations of 25, 50 and 100 mg/L for 6min significantly inhibited the increase of whole-body cortisol levels induced by NHS(p<0.05). To anti-stress effects of OF70E on behavior, we conducted OFT after the induction of NHS following pretreatment of OF70E. As results of OFT, compared with unstressed-normal group, distance moved was significantly decreased by induction of NHS in stressed-control group (p<0.05). OF70E-pretreatment blocked decreases of distance moved increased by NHS (p<0.05). And meandering movement, immobility and turn angle were significantly increased by NHS in stressed-control group compared with unstressed-normal group (p<0.05). OF70E-pretreatment prevented the increases of meandering movement immobility and turn angle by NHS (p<0.05). Conclusions : In conclusion these results suggest that OF70E-pretreatment may prevent stress responses.

• Food Science of Animal Resources
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• v.25 no.1
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• pp.7-12
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• 2005

The amino acid contents, physical and sensory properties for the loins of crossbred pigs (JJ90: live weight of 90∼100 kg; and JJ110: live weight of 110∼120 kg) and crossbred Jeju black pig (JB90: live weight of 90∼100 kg) were evaluated to investigate their quality. The total contents of structural amino acid, which were 18.15∼20.22% for all the samples without showing significant differences, included significant amount of glutamic acid, aspartic acid, lysine and leucine. The free amino acid content was 0.486% for JB90, which was greater than JJ90 and JJ110. Also, significant amount of taurine, serine, glycine, alanine, valine, and leucine could be observed in the free amino acid content of the samples. The redness (a/sup */) and yellowness (b/sup */) of JB90 were significantly higher titan those of JJ90 and JJ110. The water holding capacity, hardness, chewiness, juiciness and palatability of JJ110 and JB90 were higher than those of JJ90, but their difference was not significant.

• Korean journal of applied entomology
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• v.53 no.1
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• pp.1-6
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• 2014

The pink citrus rust mite, Aculops pelekassi (Keifer) (Acari: Eriophyoidea), is an important pest in the citrus orchards of Jeju, Korea. This study was performed to investigate the seasonal population abundance of A. pelekassi, and the effects of humidity and citrus leaf age on the multiplication of this pest. Relative humidity (RH) significantly affected the longevity and fecundity of A. pelekassi. Longevity was 7.5, 14.5 and 14.6 d and fecundity was 5.4, 21.5, and 27.1 eggs at 33, 75 and 84% RH, respectively. The leaf age of citrus significantly affected the multiplication of A. pelekassi. The population abundance on 40 day-old leaves was much higher more than 3 times that on 10-day old leaves at 4 weeks after introduction. Overwintered A. pelekassi adults between the bud scales of the citrus trees became active in late April; they were found on newly emerged leaves, followed by their settlement on young fruits in mid-June. The population levels of A. pelekassi peaked on the leaves in late June to July, and on the fruits in early August. The results obtained in this study should be useful for the control of A. pelekassi in citrus orchards in Jeju.

• Korean Journal of Environment and Ecology
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• v.28 no.6
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• pp.697-704
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• 2014

Mt. Hallasan in Jejudo has been well known as a habitat for both northern and southern limited butterflies and attracts the interests of many lepidopterists. In this study, the line transect method was used to monitor the community and similarity of butterflies monthly monitoring from May to September 2013, and the results were compared with the previous data. Through monitoring, 3,397 individuals in 26 species of 5 families were found in the present study. The monitored individuals belonging to 4 species (Aphantopus hyperantus, Eumenis autono, Lethe diana and Melanargia epimede) was 2,578 (75.9%), showing the prevalent species among the butterflies observed in the grassy area of the Mt. Hallasan. The butterflies inhabiting Mt. Hallasan showed higher similarity in the area where the open grassy space and the crowns of tree layer coexist than in landscape consisting of solely the tree layer or open grassy space. The habitation of butterflies by heights showed the altitudes between 1,665 to 1,700 m, located beneath the Baekrokdam (the crater) of Mt. Hallasan, possessed the most species and individuals. And it was also observed that the species that previously inhabited the subalpine zone moved to the area of higher altitudes together with the species that previously inhabited rather lower altitudes than the subalpine zone.