• The Transactions of the Korean Institute of Electrical Engineers B
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• v.52 no.2
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• pp.68-79
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• 2003

We estimated harmonics on power system of AC railway based on quantitatively measured harmonics and investigated the need of facilities for harmonics reduction. In order to analysis harmonics which inflow into power system due to increase in collector voltages and harmonic currents generated from the train when the railway is in operation, the railway system Is sectioned into power supply, railway line, AT, sectioning Post and subsectioning post. For analysis of extension of currents resulting from the railway loads, PWM converter, VVVF inverter and the feeder system are modeled based on the dynamic node technique(DNT). In order to test the usefulness of the DNT for analysis of harmonic effects, the measured harmonic currents and harmonic magnification ratios at the S/K substation are compared with simulation results using DNT modelling, which include the results for two cases with and without filters for suppression of harmonic currents. When 8 cars(4M4T) are in operation, the total sum of harmonic currents resulting from the train at M and T phases, which inflow into the substation along with the railway line, is calculated. Using the harmonics analysis program for railway feeder system with these data, the total harmonic distortion factor(710) at the outgoing point of KEPCO substation is computed. The calculation shows that when the maximum THD at the receiving point of H/K substation was 0.0443% which is much lower than 1.5% which is the allowable value of KEPCO at 154kV as well as IEEE-519 above 132kV This result indicates that any measure for harmonics reduction in Incheon International Airport Railway is not needed.

• Korean Journal of Plant Taxonomy
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• v.45 no.3
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• pp.266-271
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• 2015

Elaeagnus pungens Thunb., belongs to the family Elaeagnaceae, was recently recorded for the first time in Mt. Miruk, Tongyeong-si, Gyeongsangnam-do. The native distribution range of this species includes China and Japan in East Asia, while it is considered as an invasive species in North America. Elaeagnus pungens is related to E. glabra, but the species can be distinguished from its congeners by having revolute and repand leaf blades, silvery white and brown scales on the abaxial surface of the leaf, and a campanulate calyx. We propose the new Korean name 'Tong-yeong-bol-re-na-mu,' based on its first collecting site. A detailed description of vegetative and floral characteristics, trichome scanning electron micrographs, dichotomous keys, and the habitat of this species are also provided.

• Journal of the Korea Convergence Society
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• v.8 no.11
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• pp.331-342
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• 2017

The study empirically investigates the effect of mindfulness on their job satisfaction and organizational commitment of flight attendants focused on the mediating effect of job satisfaction between mindfulness and organizational commitment. Data was collected at Incheon and Jeju international airport from flight attendants working on international flight of domestic airlines. The results of this study reveal that concentration among the sub-factors of mindfulness had positive effects on job satisfaction and organizational commitment. And job satisfaction partially mediated between the sub-factor of mindfulness and organizational commitment. In order for flight attendants to avoid habitual behaviors and to increase concentration while on duty, it is important to work together to remind one another of next step of service that immediately follows and complete a checklist at the end of each step of service.

• Journal of the Korean GEO-environmental Society
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• v.7 no.5
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• pp.5-11
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• 2006

A primary factor affecting on the design of soft ground is to determine the soil properties (Compression index, Coefficient of consolidation) and the depth of soft ground. It could be the basic sources to estimate settlement behavior of soft ground. Even though the reliable soil examination equipment was used to examine soil to determine the depth of soft ground, it's very hard to find out the accurate properties of soft ground, because the condition of indoor experiment cannot reproduce the circumstances of ground perfectly. Therefore, this study was re-estimated to find out the most reliable soil properties by using back-analysis with field monitoring data of "Site preparation for Airplane Mooring of Incheon International Airport Phase II Development" for 317days.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.1228-1236
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• 2006

In soft ground, There are many case that Bridge Abutment is constructed after soil improvement in order to reduce the Negative Friction and prevent from Lateral Soil movements of Bridge Abutment. That section of Horizontal Subgrade Reaction $Modulus(K_h)$ derivation has much important mean due to Horizontal Stability of Abutment. It is come from behavior of Pile and Soil within depth of $1/\beta$. After Soil Improvement, however, If Bridge Abutment was construction, It's not impossible to carry out Field Investigation After Ground of Improved at design stage. Therefore, It's not able to derivate Horizontal Subgrade Reaction $Modulus(K_h)$. Therefore, in this case of study compare with Field Construction Test Data in order to derivation of Horizontal Subgrade Reaction $Modulus(K_h)$ and Reliability in terms of ground of Bridge Abutment by Sand Compaction Pile(SCP) during design of The 2nd Bridge Connection Road of Incheon International Airport. In this paper determine, Soil Property(The rate of strength increase, $c_u$ so on) and Horizontal Subgrade Reaction $Modulus(K_h)$ after soil improvement at design stage.

• Fashion & Textile Research Journal
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• v.16 no.4
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• pp.554-563
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• 2014

The purpose of this study was to investigate the purchase behavior, the level of shopping satisfaction for inbound Chinese tourists buying fashion products and the analysis of the influence of fashion product purchase criteria and effects of store attributes toward shopping satisfaction in Korea. Subjects were selected through convenient sampling technique in Incheon International Airport. A self-administered questionnaire was developed in Chinese by translation and back-translation method. Finally, 284 questionnaire out of 420 were used for data analysis. To analyze data, factor analysis, correlation analysis, regression analysis, etc. were carried out. A used statistical package was PASW 18.0. The analysis results were as follows. First, most of the repondents were women in 20s and 30s, who were purchasing fashion products more than other during the period of travel. Second, the product purchase criteria were identified as 'practicality', 'design and quality', 'memorabilia' and 'hallyu'. As the analysis results, shopping satisfaction was influenced by 'design and quality' and 'hallyu'. Thirdly, the effects of store attributes were identified as 'product', 'environment' and 'employees'. and customer's shopping satisfaction was influenced by all of those. By the end of this paper, For the purpose of achieving more competitive fashion products, the 4P marketing strategies targeting Chinese tourists were discussed based on the results.

• Korean Journal of Agricultural Science
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• v.40 no.4
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• pp.281-287
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• 2013

In Korea, isolated cultivation has been implemented for 102 genera, including about 250 species, each of which has underwent microscopic inspection, cultivation of bacteria in selective medium, analysis of physiology and biochemistry, enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR). The number of isolated microorganisms was 8,307 in the period of 2005-2012, and bulbs and tubers had the greatest diversity of microorganisms, of 5,165 (62.2%), followed by 2,119 (25.0%) sapling, 796 (9.6%) seed, 150 (1.8%) cutting slip, 70 (0.8%) branch graft and 7 (0.1%). The number of cases which were disqualified were 413 (4.97%), after the detection of 47 disease causing species of microorganism. Viruses predominated, with 27 species, followed by 16 fungi, a viroid, a Chromalveolata and 2 further species. Top on the list of detection was Arabis mosaic virus (77 cases), followed by Tobacco rattle virus (70 cases), Lily symptomless virus (46 cases) and Penicillium expansum (46 cases).

• Korean journal of applied entomology
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• v.53 no.4
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• pp.457-460
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• 2014

Toxicity of several insecticides was tested against the brown marmorated stink bug, Halyomorpha halys (Hemiptera: Pentatomidae), and adult Gymnosoma rotundatum (Diptera: Tachinidae) in a sweet persimmon orchard. H. halys was captured using black light traps and G. rotundatum adults were collected using sticky traps lured with an aggregation pheromone, methyl-(E,E,Z)-2,4,6-decatrienoate of Plautia stali. Five insecticides, namely, bifenthrin 2 WP, buprofenzine+dinotefuran (20+15) WP, clothianidin 8 SC, dinotefuran 10 WP, and thiamethoxam 10 WP, were moderately toxic to G. rotundatum, resulting in 55.3% to 74.3% mortality. Bifenthrin 2 WP caused 93.1% mortality at 72 h within cages as a residual toxicity, and others caused varied mortalities.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.3 no.3
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• pp.103-111
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• 1998

This paper reports the sediment geochemistry and its relation to the grain size distribution in Kyeonggi Bay, Korea. Sediment samples were collected from 90 stations during the cruise crossing the bay in December 1995. Variables investigated were the sediment grain size, organic carbon content, and concentrations of AI, Fe, Mn, V, Co, Ni, Cr, Zn and Cu in the sediment. We followed the change in these variables by comparing the data obtained from this region in 1981. Distribution pattern of sediment grain size was modified from that in 1981 in some places. Near the Shihwa Dike which was completed in 1994, sediment had got finer grained. Sediment facies changed from fine to mixed facies near Youngjong Island where the tidal flat has been reclaimed for airport construction. Contents of organic matter and metals in the sediment were mostly dependent upon the sediment grain size, but an exception was found in the harbor area. The sediment in the Incheon North Harbor showed higher accumulation of organic matter and metals such as Ni, Cr, Zn and Cu.

• Research in Plant Disease
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• v.23 no.1
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• pp.82-87
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• 2017

During 2012 to 2014, a survey for the presence of viral diseases in yam plants was carried out in a field of the Institute for Bioresources Research in Gyeongsangbuk-do, Korea. A total of 88 leaf samples were collected and tested by reverse transcription polymerase chain reaction using specific primer sets. Eighty-one samples were positive for Broad bean wilt virus 2 (BBWV2), Chinese yam necrotic mosaic virus (ChYNMV), Cucumber mosaic virus (CMV), Japanese yam mosaic virus (JYMV), and Yam mild mosaic virus (YMMV), whereas Yam mosaic virus (YMV) was not detected. Additionally, seven samples were negative for all viruses. Several samples exhibited mixed (double and triple) infections. Three viruses (CMV, JYMV, and YMMV) were detected for the first time in yam plants in Korea. A BLAST search showed that three viruses shared nucleotide identities with CMV-Ca (98%), JYMV-O2 (91%), and YMMV-TG_NH_1 (86%). Thus, our findings confirmed that yam plants cultivated in Korea were infected with multiple viruses with three of these viruses reported for the first time in Korea.