• Earthquakes and Structures
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• v.7 no.6
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• pp.1241-1258
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• 2014

This is paper presents the results of an analytical study aimed at evaluating the effect of narrow-banded mainshock/aftershock seismic sequences on the response of structures built on very soft soil sites. Due to the scarce availability of recorded seismic sequences in accelerographic stations located in the lake-bed of Mexico City, artificial narrow-banded sequences were employed. In the first part of this study, a parametric investigation was carried out to identify the mainshock/aftershock ground motion features that have detrimental effects in the seismic performance of equivalent single-degree-of-freedom systems representative of framed-buildings that house standard and essential facilities. In the second part of this work, the seismic response of two (8- and 18-story) steel-moment resisting frames that house essential facilities is examined. It is concluded that buildings with fundamental periods of vibration longer than the dominant period of the mainshock can experience a significant increment in their inter-story drift demands due to the occurrence of an aftershock.

• The Korean Journal of Zoology
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• v.23 no.3
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• pp.161-194
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• 1980

The authors examined intertidal and sublittoral balanomorph barnacles which were collected from 38 localities in South Korea during the period from 1963 to 1978. 2. Identified and classified materials are composed of 15 species and 2 subspecies, all of which are described, under 10 genera and 5 damilies, of which 2 species and 1 subspecies are new to Korea as follows: Chelonibia patula, Chirona (Striatobalanus) amaryllis, Solidobalanus (Hesperibalanus) hesperius hesperius. 3. As dominant species, Chthamalus challengeri and Tetraclita squamosa japonica are widely distributed in Korea through East Sea, South Sea and Yellow Sea. 4. Balanus albicostatus and B. kondakovi are commonly found in intertidal brackish waters of Yellos Sea and South Sea, whereas, B. trigonus and Megabalanus rosa are typical sublittoral forms.

• Journal of environmental and Sanitary engineering
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• v.19 no.2
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• pp.37-44
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• 2004

Flora and standing crops of the periphyton communities were examined at five sites in the mountainous streams of the Dam of Peace, Korea, from June to November 2003. The attached algal communities comprised totally 76 taxa belong to the 5 classes. In species composition, diatoms and green algae overwhelmingly dominated the periphyton communities although their standing crops were low. During the survey period, major dominant species were Navicula gregaria and Nav. pupla var. capitata, as 11.7% and 8.9% of total standing crop, respectively. Other subdominant species were Scenedesmus ecornis and Spirogyra weberii in green algae, Cymbella affinis, Cymbella minuta. Fragilaria capucina, Melosira varians, Naw. cryptocephala, Nav. exigua var. capitata, Nav. gregaria, Nit. sublineuris in diatom. In the seasonal appearances, S. ecornis and Oscillatoria nigra were occurred in summer, C. affinis and F. capucina in autumn, and N. sublinearis, and species Spirogyra weberii in winter, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.4
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• pp.429-436
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• 2017

The seasonal and interannual variations in fish assemblages in the coastal waters off Gijang were examined with an otter trawl from 2015 to 2016. A total of 59 fish species was collected during the study period. The dominant species were Caelorinchus multispinulosus, Clupea pallasii pallasii and Chelidonichthys spinosus. Seasonal changes in fish assemblages appeared to be distinct in the study area. The fish assemblages in summer and autumn were clearly distinguishable from those in other seasons, and the largest numbers of species and individuals were captured in winter and summer, respectively. Because fish assemblages are closely related to changes in water temperature, long-term changes in water temperature can have a significant impact on the productivity of offshore fisheries by changing fish species composition, habitat migration, and growth rate of fish.

• Journal of Chest Surgery
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• v.25 no.12
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• pp.1516-1522
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• 1992

Thirty patients with myasthenis gravis[MG] underwent transternal extended thymectomy between 1983 and 1992 in Pusan National University Hospital. The age of patients was 11 to 62 years[mean; 35.2 years] with female dominant[M: F=l: 4]. According to modified Osserman classification, group I was in 6, II A in 7, II B in 13, III in 2, IV in 2 patients respectively. Their clinical response to thymectomy was evaluated. The follow-up period ranged from 2 months to 9.5 years[average; 51.3 months]. Fourteen patients[13.3%] had remission and eleven[43.3%] were improved after operation; half of patients were benefited from operation. Twenty patients had thymic hyperplasia and seven had non-infiltrating thymoma. In thymomatous MG one patient had remission and five were improved. Postoperative death was in a female patient. The cause of death was respiratory failure in the severe generalized MG preoperatively.

• Transactions of the Korean Society of Mechanical Engineers
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• v.13 no.2
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• pp.271-276
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• 1989

Flame spreading over a hydrocarbon fuel surface has been investigated for liquid fuels such as kerosene and diesel, using thermocouple. Without forced convection, it was clearly found that the flame spreading was mainly controlled by the liquid fuel surface flow. Furthermore, the radiative heat transfer was dominant over a conductive heat transfer in kerosene. But in diesel the latter was found to be more influential than the former, when the direction of windflow was the same as that of flame spreading. The oscillation period and amplitude of the flame spreading velocity increase if the windflow is blowing in the direction of the flame spreading velocity, and decrease if the direction of windflow is blowing against the flame spreading direction.

• Korean Journal Plant Pathology
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• v.14 no.5
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• pp.496-501
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• 1998

Incidence of rice blast on new rice cultivars and elite lines was observed from 1995 to 1997 in Icheon, Chuncheon, Jecheon and Naju areas. The observation was made in the nurseries and fields. In the nurseries, three cultivars Grubyeo, Sangjuchalbyeo and Suwon 414 showed moderate levels of resistance to leaf blast, with the disease index 0 to 5. From the field observation, it was found that cultivars Heugjinjubyeo and Unbong 18 were highly resistant to leaf blast, but susceptible to neck blast. In general, there was a great variation yearly and regionally in the incidence of neck blast within the same cultivar, ranging from 0 to 100%. However, the range of neck blast infection was relatively narrower in the cultivars Yunghaebyeo (0∼2.4%) and Suwon 414 (0∼2.2%) during observation period. Races of rice blast fungus were variable at different areas. Among them dominant races were KI-409, KJ-201 and KJ-301.

• Ocean Science Journal
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• v.43 no.3
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• pp.135-146
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• 2008

The monthly distribution of zooplankton communities in Han River estuary was investigated at two stations from July 1998 to June 1999. Monthly mean abundance of total zooplankton varied remarkably, with the range from 20 $indiv.{\cdot}m^{-3}$ to 19,600 $indiv.{\cdot}m^{-3}$. During the study period, dominant species of zooplankton community were dinoflagellate Noctiluca scintillans, copepods Paracalanus indicus, Paracaanus crassirostris, Acartia hongi, Acartia ohtsukai, and meroplanton cirriped larvae. According to tidal states, relative high abundance occurred at high tide without regard to season. The temporal distribution of abundance implied that the reduced salinity probably limited the zooplankton populations and the fluctuations of salinity were an important factor in the variation of abundance. However, the results of salinity tolerance test shows that the variations in salinity do not directly influence the decrease of abundance. This study shows that the relatively high abundance of zooplankton near high tide seems to be related with the expansion of abundant zooplankton inhabiting Incheon coastal waters through tidal currents.

• Journal of Surface Science and Engineering
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• v.36 no.3
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• pp.272-283
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• 2003

Mild steel and zinc specimens were tested in five atmospheric testing sites of Vietnam in order to collect the corrosion databank as well as to study the corrosion mechanism in tropical conditions, in period of 1997-2000. The results obtained showed that the corrosion rate of steel is in the range of $10-50\;{\mu}m/year$ and of zinc is of $1-5\;{\mu}m/year$. They are interpretable in the comparison with the data obtained in different countries in the South East Asian as well as previous reports of Vietnamese nation project In atmospheric corrosion. The main factors affecting the corrosion in Vietnam tropical conditions are TOW (time of wetness) and salinity. The relationship between sulfur dioxide and corrosion of metals, particularly, zinc was not found clearly. An explanation was suggested about the complex effect of different pieces present in tropical atmosphere and about the alternative of the dominant factors such as humidity, salinity or temperature.

• Bulletin of the Korean Chemical Society
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• v.23 no.6
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• pp.799-803
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• 2002

Partial oxidation of methane has been conducted over $CeO_2$and it has been found that $CeO_2$has an extraordinary catalytic activity in the reaction. Its activity was strongly dependent on the $CH_4/CO_2$ ratio. Total combustion was dominant with stoichiometric feed ratio$(CH_4/O_2=$ 2.0) but partial oxidation was achieved between the $CH_4/O_2$ ration of 3.8 4.3 and the period depended upon the feed composition. The proposed raaction mechanism it that oxygen vacancies in raduced deria are supplied with oxygen molecules from the reactant, and then activate adsorbed oxygen, followed by releasing activated axygen species reacting with methane to produce $H_2$ and CO.