• Transactions of the Korean hydrogen and new energy society
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• v.28 no.5
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• pp.465-470
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• 2017

Sulfonated fluorinated block copolymers having diphenyl units were mixed with the sulfonated cationic conductive polymers at an optimum mixing ratio to form hybrid membranes for fuel cells and their characteristics were studied. 2D and 3D AFM topology analysis confirmed that the number of hydrophilic units in the hybrid membrane was improved. Through the FE-SEM, the microstructure of the hybrid membrane implied hydrogen bonding and pi-pi interactions, and EDAX confirmed carbon, oxygen, sulfur, and fluorine. The thermogravimetric analysis showed that the hybrid membrane was thermally stable and the hydrophilicity of the hybrid membrane was increased by the contact angle of water droplets. As a result, it was confirmed that the cation conductivity increased by a factor of 1.8 times as the number of acidic domains in the hybrid film increased.

• International Journal of Computer Science & Network Security
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• v.21 no.1
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• pp.192-200
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• 2021

In the mid of the December 2019, the virus has been started to spread from China namely Corona virus. It causes fatalities globally and WHO has been declared as pandemic in the whole world. There are different methods which can fit such types of values which obtain peak and get flattened by the time. The main aim of the paper is to find the best or nearly appropriate modeling of such data. The three different models has been deployed for the fitting of the data of Coronavirus confirmed patients in Pakistan till the date of 20^th November 2020. In this paper, we have conducted analysis based on data obtained from National Institute of Health (NIH) Islamabad and produced a forecast of COVID-19 confirmed cases as well as the number of deaths and recoveries in Pakistan using the Logistic model, Gompertz model and Auto-Regressive Integrated Moving Average Model (ARIMA) model. The fitted models revealed high exponential growth in the number of confirmed cases, deaths and recoveries in Pakistan.

• YAKHAK HOEJI
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• v.47 no.5
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• pp.331-338
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• 2003

A butyrolactone ester of cefazolin (CFZ-BTL) was synthesized by the esterification of cefazolin (CFZ) with $\alpha$-bromo-${\gamma}$-butyrolactone. The synthesis was confirmed by the spectroscopic analysis. The CFZ-BTL was more lipophilic than the CFZ when assessed by n-octanol/water partition coefficients at various pH. The CFZ-BTL itself did not show any antimicrobial activity in vitro, but after oral administration of CFZ-BTL to rabbits, exerted significant anti-microbial activity in serum samples when measured by the inhibion zone method in nutrient agar plates, due to conversion of CFZ-BTL to an active metabolite, probably CFZ, in the body. The CFZ-BTL was also converted into CFZ as confirmed by in vitro incubation study, with tissue homogenates (liver, blood and intestine) of rabbits. The liver showed the fastest conversion rate, probably via the hydrolysis mechanism. In vivo metabolism of CFZ-BTL to CFZ was also confirmed in vivo serum samples by HPLC. The oral bioavailability of CFZ-BTL in rabbits was 1.6-fold increased when compared to CFZ, resulting from followed by enhanced lipophilicity increased passive absorption in the intestine.

• Microbiology and Biotechnology Letters
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• v.28 no.1
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• pp.21-25
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• 2000

We have got several clones from Serratia marcescens which stimulated the cells to use maltose as a carbon source in Escherichia. coli TP2139 ( lac, crp). One of the cloned genes, pCKB17, was further analyzed. In order to find whether the increased expression of the gent was under the direction of maltose metabolism, we constructed several recombinant subclones. We have found that the clone, pCKB17AV, codes maltose metabolism stimulation(mms) gene. E. coli transformed with the cloned gene showed increase in the activity of maltose utilzation, The recombinant proteins expressed by multicopy and induction with IPTG, one polypeptide of 29-kDa, was confirmed by SDS-PAGE. The overexpression of maltose-binding proter protein in the presence of mms gene was confirmed by Western blot analysis. Southern hybridization analysis confirmed that the cloned DNA fragment was originated from S. marcescens chromosomal DNA.

• Journal of The Korean Astronomical Society
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• v.41 no.2
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• pp.17-22
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• 2008

We present an analysis of the soft X-ray emission of MRK 841 to investigate its long-term variation. The light variation of MRK 841 for three different energy bands of soft, medium, and hard values were studied. The maximum variability with a factor of 5 for about two years was confirmed at all three different bands. The light curves exhibit a gradual variation of brightness. In addition to a gradual variation, the short- term or micro variation was also confirmed with a factor of about two for all three different bands. The light variation of each band did not exhibit a correlation between them, but the flare event is strongest in the soft band. The hardness ratio for hard and soft bands shows irregular variation but there was no correlation between them. It was confirmed that there is a gradual decrease of the photon index. Results of our analysis are discussed within the framework of the accretion disk phenomenon.

• Journal of Engineering Education Research
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• v.26 no.1
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• pp.20-26
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• 2023

In this study, as a competency strengthening program to support learner-centered education, we developed the 'Capstone-design competency Program' for the purpose of cultivating the 4C skills and problem-solving ability required as core competencies of the 21st century. The program was based on the project method, and strategies were derived and materialized for each step through core competency analysis. Then, the validity was confirmed through the implementation of the program. As a result of the implementation of the program, it was confirmed that this program was effective in cultivating the core competencies of college students. In addition, it was confirmed that learners showed results such as specific reflection on core competencies, changes in perspective, and action plans, so that the possibility of actual application was high.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.256-257
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• 2017

This paper presented polymerization reactivity of fly ash based geopolymer with alkaline activator type. As a result, the compressive strength development properties of the geopolymer can be confirmed from the combination of the amorphous Si and Al contents in the fly ash and the alkaline activators. Although the direct correlation between the polymerization reactivity of the geopolymer and the development of compressive strength could not be confirmed through an X-ray diffraction analysis, it could be confirmed through scanning electron microscopy.

• Journal of Preventive Medicine and Public Health
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• v.53 no.3
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• pp.168-170
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• 2020

On December 31, 2019, the Chinese government officially announced that the country had some cases of pneumonia with an unknown cause. By February 8, 2020, there were 24 confirmed cases in Korea, and the number of cases has steadily increased since then. On March 9, 2020, the cumulative number of confirmed cases in Korea was 7382, with 51 deaths. This study examines the characteristics of the coronavirus disease 2019 (COVID-19) outbreak from the perspective of the large-scale number of confirmed COVID-19 cases and deaths. This study is significant in that it emphasizes the precautionary principle in preventing and managing infectious diseases, and makes suggestions for urgently needed public health policies.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.207-208
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• 2019

In this study, compressive strength was measured to evaluate the initial strength of cement mortar substituted with coal gasification slag containing desulfurized gypsum, and the reactivity of desulfurized gypsum was confirmed. In order to improve the reactivity, 2% gypsum mixed type and gypsum unfedged type specimens were fabricated and the influence of desulfurization gypsum on compressive strength of coal gasification slag and blast furnace slag fine powder replacement cement mortar was compared and confirmed. As a result of the experiment, it was confirmed that the initial compressive strength of the specimen containing the desulfurized gypsum was improved at the initial stage.

• Journal of Industrial Technology
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• v.26 no.B
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• pp.43-51
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• 2006

Through the result of calculating the deviation between the value calculated from two-dimensional number formula, one-dimensional number interpretation, and curving part water surface type calculation method, we could confirmed that the deviation is reduced more than 50% when we use curving part water surface type calculation method. Also it was confirmed that there occurs the reduction rate of maximum 59% as the result of comparing with one-dimensional number interpretation since the reduction rate of safe room height was 20%, in 500 CMS of flood water quantity when we planted the construction of levee by curving part water surface type calculation method. And therefore, we have confirmed that the curving water surface type calculation method can be used as a simple formula in rivers with water quantity less than 500 CMS that flows in and out in Jess than 90 degree angle.