• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.4
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• pp.331-338
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• 2000

The algicidal effects of marine bacteria were investigated and a strain, which had the strongest algicidal activity against the harmful dinoflagellate, Cochiodinim polykrikoides was selected. The bacterium was isolated in seawater during the period of blooming of C. polykrikoides in Masan Bay. This algicidal bacterium was identified as Micrococcus sp. LG-5 by means of morphological and biochemical tests. The optimal culture conditions of Micrococcus sp, LG-5 were $25^{\circ}C,\;pH 7.0\;and\;3.0{\%}$ NaCl concentration. The algicidal activity of Micrococcus sp. LG-5 was significantly increased to maximum value in the late of logarithmic phase of cell cuture. In addition, the culture filtrate ($pore size,\;0.1{\mu}m$) of Microcoocus sp. LG-5 showed strong algicidal effects. The cell numbers of C. polykikoides were decreased from $1.2{\times}10^4 cells/ml\;to\;less\;than\;2{\times}10^3\;cells/ml$ within 3, 6, 30 hours at the concentrations of culture filtrate $10{\%},\;5{\%}\;and\;1{\%}$, respectively. These results indicated that the algicidal effect was mediated by certain substances released from Microooccus sp. LG-5.

• Journal of the Korean earth science society
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• v.31 no.6
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• pp.573-583
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• 2010

A paleobotanical study of the fossil woods has been carried out from the Tertiary Janggi Group, Pohang Basin. Three species belonging to three genera of Ulmus sp., Prunus sp., and Acer sp. were identified from the Lower Coalbearing Formation, and two species of two genera of Taxodioxylon sp. and Fagus hondoensis (Watari) from the Upper Coal-bearing Formation. As our specimens are mostly poorly preserved, it is difficult to give clear specific names, but mostly are all characteristic constitutional elements of the Miocene fossil woods in Korea. The values of mean sensitivity measured from the fossil woods of Lower and Upper Coal-bearing Formations are 0.367 and 0.370 respectively, but they are more than 0.30. Based on the present two data mentioned above, it stands to reason that there were many changes in the water supply to the roots of the woods or having influence to some degree each year because of the seasonal changes in rainfall.

• Journal of Digital Convergence
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• v.18 no.12
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• pp.285-292
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• 2020

The purpose of this study is a descriptive investigation study to find out the knowledge, awareness and performance of the nurse's standards precaution(SP) and to identify the factors affecting the performance of them. The research method was collected through a questionnaire from nurses at two general hospitals in B city and analyzed with technical statistics, t-test, ANOVA, Person's correlation coefficient and Multiple regression using the SPSS program. As a result of the average level of knowledge of the SP 22.55/25, recognition 3.68/4, and performance 3.77/4. The recognition of SP and implementation of SP(r=.250, p=.003) had a significant amount of correlation. The influence factor on the implementation of the SP was recognition of the SP(β=-.582, p=.001). Therefore, in order to improve the performance of SP and to respond well to new respiratory infections, accurate awareness of the SP of nurses and opportunities for systematic education and participation in education are needed by medical institutions.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.15 no.2
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• pp.68-71
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• 2010

This study was performed in order to obtain basic data of macrobenthic community in continental shelf exclusive economic zone (EEZ), before sand excavation. The species number of macrozoobenthos was 157, mean density was 2,529 ind./$m^2$ and mean biomass was 231.8 $g/m^2$ in November, 2000. The species number of macrozoobenthos was 179, mean density was 3,773 ind./$m^2$ and mean biomass was 391.2$g/m^2$ in February, 2001. Dominant species were Ampelisca sp. and Photis sp. in amphipods, Ophiactis branchygenys in ophiuroids and Nothria sp. and Eunice sp. in polychaetes. In the proportion of feeding types of macrobenthos, surface deposit feeders were most dominant feeding group, and followed by carnivores, subsurface deposit feeders, and filter feeders. Species diversity index (H') was high ranging from 2.5 to 3.5 at most sites.

• KSBB Journal
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• v.11 no.2
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• pp.201-210
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• 1996

The production of polyhydroxyalkanoate(PHA) from glucose by batch and fed-batch culture of Pseudomonas sp. HJ was studied. In batch culture using fermentor, 400 rpm of agitalion speed, 2 vvm of aeration rate, 18 hours of inoculum age, and 5% (vlv) of inoculum size were optimal. PHA production was not increased by deficiency of oxygen. In a batch culture, the final call mass was $6.251g/\ell$, and PHA content was 20% of dry cell weight. In a constant feeding fed-batch culture, cell mass increased to $33.24g/\ell$, and PHA content reached 48.9% of dry cell weight. In an intermittent feeding fed-batch culture, cell mass increased to $37.89g/\ell$, and PHA content reached 53.5% of dty cell weight.

• Microbiology and Biotechnology Letters
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• v.48 no.3
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• pp.337-343
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• 2020

In this study, the medium optimization for cell growth and metabolite formation of Haematococcus sp. under mixotrophic cultivation was investigated. As a result, modified MS medium was selected as the basal medium; glucose was selected as the carbon source, with an optimum concentration of 10 g/l, and potassium nitrate was chosen as the nitrogen source, with an optimum concentration of 1.9 g/l. Under optimum conditions, Haematococcus sp. demonstrated an increase in biomass concentration from 0.18 gDW/l to 5.58 gDW/l in 14 days, after which there was a 31-fold increase in its growth. At the same time, the concentrations of chlorophyll and carotenoids were 172.16 mg/l and 42.33 mg/l, respectively. This work will contribute to the basic data for mass cultivation of microalgae.

• Journal of Digital Convergence
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• v.16 no.4
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• pp.231-249
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• 2018

The purpose of this study is analyze the factors affecting the standard precaution(SP) performance on the knowledge, awareness, attitude and safety environment for SP of healthcare workers of general hospitals. The research method was a descriptive research study. The subject were 262 of healthcare workers of general hospitals. The data were analyzed using descriptive statistics, t-test, Chi-square test, ANOVA, Person's correlation coefficient and Multiple regression analysis using the SPSS program. As a result of the correlation analysis SP Performance was positively correlated with attitude (r=.18, p=.003), safety environment (r=.42, p<.001) and awareness (r=.63, p<.001). As a result of the stepwise multiple regression analysis on the factors influencing SP performance were SP awareness and safety environment. Therefore, in order to improved performance of SP, it's important to improve a awareness and safety environment of SP. Different and persistent infection management educational programs that consider the occupational characteristics and monitoring are required.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.4
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• pp.395-400
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• 1991

Effects of Various Chemical Substrates on Heat Resistance of Isolated EnterobTo pursue the various properties of Enterobacter sp. which may give an outbreak of food-borne disease to man, isolated from the meats and the small intestines of wild mice, and to offer the significant data in the fields of food hygiene and public health this study was carreied, 5 strains of Enterobacter sp. were isolated from the above samples. 5 strains isolated from sample sources were 1 strain (E. aerogenes) from the beeves, 2 strains (E. aerogenes, E intermedium) from the pork and 2 strains (E. aerogenes, E. cloacae) from the small intstines of wild mice. Of total isolatd 89 strains, including non-Enterobacter sp., these numbers of 5 isolates were showed as 5.6% of dection rate. On heating at temperature of $55^{\circ}C$ for 30min., these 5 stratins were generally more resisted in the 0.1M phosphate buffer when such chemical substrates as 0.1M glycine, 5% mannitol or 0.5% sorbitol was added to it whereas they were appeared weaker resistances in 0.1M phosphate buffer when 1% sodium citrate, 1% casein, 10% sodium chloride or 0.1M systein was infused into it.cter sp.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.15 no.3
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• pp.1-11
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• 2016

The present study aims to evaluate transfer resistance factors in railway stations and draw new implications. The data used for the model estimation are RP (revealed preference) data and SP (stated preference) data. Two types of models were used for the analysis: integration model which combined line-haul stage, transfer stage and shuttle stage and separation model which assessed the three stages separately. The results revealed that while bulk freight shippers mainly focused on line-haul stage, they put emphasis on transfer stage as well. It's especially notable that transfer stage was considered more important than shuttle stage. Therefore, in future transportation policies concerning rail freight, it would be crucial not only to enhance the competitiveness of line-haul stage but also make improvements in transfer stage regarding railway stations.

• Journal of Korean Society of Transportation
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• v.20 no.4
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• pp.39-48
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• 2002

본 논문의 목적은 교통계획 및 투자 사업의 평가에 있어 대기오염 요소를 고려하기 위해 필수적인 기초자료인 대기오염에 의한 경제적 가치를 추정함에 있다. 이를 위하여 가상적인 주택선호자료를 바탕으로 대기오염 개선에 대한 가구의 지불용의액을 추정하고 이를 바탕으로 대기오염 피해의 화폐적 가치를 추정한다 특히, 국내에서는 적용된 바 없지만 마아케팅 및 교통수요 분석 부문에 있어 시간가치, 교통수단의 안락감 등 비계량적 요소의 경제적 가치 측정에 많이 사용되는 SP(Stated Preference)기법을 사용해서 대기오염 피해에 대한 화폐가치를 추정한다. 연구결과 가구의 점유형태에 따라 대기오염에 대한 경제적 가치가 유의적인 차이가 존재하며 도로교통에 의한 대기오염 1%의 경제적 가치는 240만원/가구.년으로 분석되었다. 대기오염물질별 경제적 가치를 살펴보면 $O_3$ 0.01ppm의 경제적 가치는 55.40만원/가구.년, N$O_2$ 0.01ppm 18.33만원/가구.년으로 추정되었다. 본 연구를 통해 교통투자사업의 평가에 있어 환경적 요소를 고려할 수 있는 기초자료를 마련하였으며, 교통분야 뿐만 아니라 환경관련 정책의 수립 분석에 중요한 기초 결과가 제시되었다. 본 결과가 교통분야에 더욱 유용하게 사용되기 위해서는 교통투자사업 또는 교통관리에 따른 교통량의 변화와 대기오염물질 배출량의 관계에 대한 연구가 추가적으로 필요하다고 판단되며 이 연구가 이루어지면 본 연구가 제시한 결과치는 교통투자사업의 편익/비용 분석에 중요하게 사용될 수 있을 것으로 판단된다. 본 연구의 한계로서는 조사지역이 전국에서 환경오염이 심한 서울지역에서 조사가 한정되었다는 점이며 이에 대한 앞으로의 연구가 필요하다.