• Journal of Microbiology and Biotechnology
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• v.21 no.11
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• pp.1151-1158
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• 2011

In this study, a galactooligosaccharide (GOS) was synthesized using active ${\beta}$-galactosidase (${\beta}$-gal) inclusion bodies (IBs)-containing Escherichia coli (E. coli) cells. Analysis by MALDI-TOF (matrix-assisted laser desorption/ionization-time of flight) mass spectrometry revealed that a trisaccharide was the major constituent of the synthesized GOS mixture. Additionally, the optimal pH, lactose concentration, amounts of E. coli ${\beta}$-gal IBs, and temperature for GOS synthesis were 7.5, 500 g/l, 3.2 U/ml, and $37^{\circ}C$, respectively. The total GOS yield from 500 g/l of lactose under these optimal conditions was about 32%, which corresponded to 160.4 g/l of GOS. Western blot analyses revealed that ${\beta}$-gal IBs were gradually destroyed during the reaction. In addition, when both the reaction mixture and E. coli ${\beta}$-gal hydrolysate were analyzed by high-performance thin-layer chromatography (HP-TLC), the trisaccharide was determined to be galactosyl lactose, indicating that a galactose moiety was most likely transferred to a lactose molecule during GOS synthesis. This GOS synthesis system might be useful for the synthesis of galactosylated drugs, which have recently received significant attention owing to the ability of the galactose molecules to improve the drugs solubility while decreasing their toxicity. ${\beta}$-Gal IB utilization is potentially a more convenient and economic approach to enzymatic GOS synthesis, since no enzyme purification steps after the transgalactosylation reaction would be required.

• Journal of Korea Water Resources Association
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• v.38 no.6 s.155
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• pp.505-515
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• 2005

Two representative river water quality models have been compared in this paper. The steady water quality model, QUAL2E, and the unsteady model, CE-QUAL-RIV1, have been chosen for comparative simulations. Under same reaction coefficients and boundary conditions, the water quality of the Geum river below the Daechung dam has been simulated using two different models, and the water quality equations are compared each other. Since basic model algorithm is very close, the input data required for model run is very similar. Upon the simulation under steady condition, the results of two models show very good agreement especially for BOD, DO, and $NH_3-N$, while the results of specific constituent such as dissolved P is quite different. As a result, dominant water quality parameters to compute each corresponding water quality variables are summarized and tablized through the sensitivity analysis.

• Cross-Cultural Studies
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• v.26
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• pp.405-444
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• 2012

This paper is based on the view that film should be conceived as a form of cultural practice whose meaning is always in the process of being produced within diverse socio-cultural contexts and aims to examine the ways in which the meaning of Korean film is (re)mediated or received in diverse cultural contexts outside the country. In this paper, we employ two theoretical grounds. Firstly, it positions itself in line with the audience studies within the field of cultural studies where the audience is conceived as active agents who produce the meaning of a popular culture text. The recruitment of the theoretical propositions from the audience studies enables recognition of the significance of the reception in film practice which recently seems to be oriented on production and distribution. Secondly, we conceive transnationality of film as that which is being produced in the process of transaction between the film and the audience, that is to say, transnationality is a form of discourse that emerges upon cultural interaction. The empirical work involves examination of a set of reviews of four films--Chihwaseon, Oldboy, Thirt, Poety--that have been published in daily newspapers and some popular film magazines in the U. S., the U. K. and France. Through the analysis of the film reviews, we identify four interpretive schemes or rather discourses recruited via which the Korean films are approached and understood: auteurism, formalism, universal themes, emotional response. We propose that these four kinds of discourse provide a common ground for the audience from different cultural backgrounds to understand Korean film. Furthermore, we also suggest that transnationality of Korean cinema needs to be reconsidered in terms of the reception as the audience from different socio-cultural backgrounds should be understood as active agents who are capable of engaging in Korean cultural texts such as film in their own way producing various meanings and these are also constituent of the meaning of the cultural texts.

• Journal of the Korean Solar Energy Society
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• v.33 no.3
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• pp.58-66
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• 2013

Recently, PV module that the most important part of the photovoltaic system is more widened to lower manufacturing costs for module. However, the broad PV module results to the serious mechanical damage corning from installation circumstances such as snow, wind etc of snow and finally lead to the dramatic degradation of the electrical behavior of PV module. In this paper, 3 kinds of PV modules that consist of the different thickness and area of front glass and the diverse cross sectional structures of the frame are prepared for this experiment. The drooped length and electrical outputs of the PV modules are measured by means of applying 600Pa mechanical load to the PV modules from 1200Pa to 5400Pa base on the mechanical load test procedure of K SC IEG 61215 standard. The simulation data are obtained by the simulation tool as ANSYS and those are validate by comparing with the those experimental results figure out relations between the deformation and the constituent part of PV module.

• Journal of Korean Critical Care Nursing
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• v.12 no.2
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• pp.39-49
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• 2019

Purpose : The purpose of this study was to identify the extent to which intensive care unit (ICU) nurses' perceptions of life-sustaining treatment decisions and "a good death" affect attitudes toward terminal care. Method : Participants included 109 ICU nurses from three university hospitals. Data were collected using structured questionnaires, and collected data were analyzed using a t-test, ANOVA, the $Scheff{\acute{e}}$ test, Pearson correlation coefficients, and a multiple regression analysis (SPSS 24.0 program). Results : Perceptions of life-sustaining treatment decisions and a sense of closeness (a constituent for the awareness of "a good death") were positively correlated with terminal care attitudes. The factors affecting terminal care attitudes were a clinical career in ICU (${\beta}=.20$, p =.035), a sense of closeness(${\beta}=.19$, p =.041), and the perception of a life-sustaining treatment decision (${\beta}=.22$, p =.017). This finding indicates that more than 10 years of experience in ICU, a greater sense of closeness, and a higher view of life-sustaining treatment decisions results in more positive attitudes toward terminal care. The explanatory power of these variables on terminal care attitudes was 14% (F=6.84, p < .001, Adj $R^2=.140$). Conclusion : A sense of closeness and the perception of life-sustaining treatment decisions were identified as the factors affecting terminal care attitudes. Thus, various programs must be developed to raise awareness among ICU nurses of "a good death" and perceptions of life-sustaining treatment decisions.

• Metals and materials international
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• v.24 no.6
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• pp.1376-1385
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• 2018

Ultrasonic melt treatment (UST) was applied to an A390 hypereutectic Al-Si alloy in a temperature range of $750-800^{\circ}C$ and its influence on the solidification structure and the consequent increase in strength was investigated. UST at such a high temperature, which is about $100^{\circ}C$ above the liquidus temperature, had little effect on the grain refinement but enhanced the homogeneity of the microstructure with the uniform distribution of constituent phases (e.g. primary Si, ${\alpha}-Al$ and intermetallics) significantly refined. With the microstructural homogeneity, quantitative analysis confirmed that UST was found to suppress the formation of Cu-bearing phases, i.e., $Q-Al_5Cu_2Mg_8Si_6$, $Al_2Cu$ phases that form in the final stage of solidification while notably increasing the average Cu contents in the matrix from 1.29 to 2.06 wt%. A tensile test exhibits an increase in the yield strength of the as-cast alloy from 185 to 208 MPa, which is mainly associated with the solute increment within the matrix. The important role of UST in the microstructure evolution during solidification is discussed and the mechanism covering the microstructure-strengthening interrelationship of the ultrasonically treated A390 alloy is proposed.

• Journal of the Korean Society of Earth Science Education
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• v.12 no.2
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• pp.151-164
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• 2019

The purpose of this study is to find out the effects of reconstructing unit 'Seasonal Change' using step-by-step questioning for concepts changes to adjusting misconceptions of elementary school students. Most students have pre-conceptions at describing seasonal changes based on their experiences. Therefore, in newly developed unit, we reconstructed unit to include core teaching and learning contents by finding out common pre-conceptions of students and specifying purpose of teaching at misconceptions found in pre-conceptions as 'constituent of class for conceptual change'. After the scientific concept test, the result of 24 students in experimental group is statistically significant. Also, according to the result of qualitative analysis, the number of activated conceptional resources and degree of specificity in explaining seasonal changes are higher than that of control group.

• Korean Journal of Pharmacognosy
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• v.52 no.3
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• pp.192-201
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• 2021

Dangguisu-san (DGSS) is widely known traditional herbal medicinal formula in Korea for treatment of traumatic injury by traffic accident, ecchymosis, abdominal distension and anti-thrombosis of blood. This study was conducted to develop the simultaneous analyze method using high performance liquid chromatography (HPLC) and examine the effect of anti-inflammatory activity of DGSS-dry extract (DGSS-DE) and DGSS-mix extract powder (DGSS-MEP). Physicochemical characteristics of DGSS-DE and DGSS-MEP showed that there is no significant difference in pH, titratable acidity, total soluble solid content and browning degree except for color value (L, a, b). 15 functional constituents of DGSS were identified and the correlation coefficient values of DGSS-DE and DGSS-MEP were conformed 0.950. Also, DGSS-DE and DGSS-MEP significantly decreased the secretion of nitric oxide (NO), prostaglandin E₂ (PGE₂), interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) through inhibited expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), IL-1β, IL-6, and TNF-α. From these result, DGSS-MEP showed similar chemical composition and anti-inflammatory effect to DGSS-DE. Therefore, DGSS-DE and DGSS-MEP may be useful as potential source of drug to prevent inflammation.

• Korean Journal of Metals and Materials
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• v.47 no.9
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• pp.523-532
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• 2009

In this study, four API X80 linepipe steel specimens were fabricated with varying cooling rates and finish cooling temperatures, and their microstructures and crystallographic orientations were analyzed to investigate the effects of cooling conditions on their tensile and Charpy impact properties. All the specimens consisted of acicular ferrite, granular bainite, and secondary phases such as martensite and martensiteaustenite constituent. The volume fraction of secondary phases increased with increasing cooling rate, and the higher finish cooling temperature resulted in the reduction in volume fraction and grain size of secondary phases. According to the crystallographic orientation analysis data, the effective grain size and unit crack path decreased as fine acicular ferrites having a large amount of high-angle grain boundaries were homogeneously formed, thereby leading to the improvement of Charpy impact properties. The specimen fabricated with the higher cooling rate and lower finish cooling temperature had the highest upper shelf energy and the lowest energy transition temperature because it contained a large amount of fine secondary phases homogeneously distributed inside fine acicular ferrites, while its tensile properties well maintained.

• Journal of the Korean Society of Propulsion Engineers
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• v.25 no.4
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• pp.43-52
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• 2021

In this study, performance modeling and simulation of a gas turbine engine, a constituent module, was performed for the integrated control of the CODOG structure, mechanical propulsion systems. The engine model used MATLAB/Simulink to facilitate integration with the host controller and other components, and was configured to enable input/output settings suitable for the system configuration and purpose. In general, engine manufacturers do not provide performance data for the engine and components. Therefore, as a modeling method for a gas turbine, a CMF method that obtains performance data by scaling the map of components was applied. Using the generated model and simulation program, steady-state and dynamic simulation analysis tests were performed, and reliability within 5% of the maximum error was secured for the final output of power.