• Journal of Korean Society of Environmental Engineers
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• v.28 no.12
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• pp.1287-1292
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• 2006

Constructed wetlands are well known as highly efficient system to treat wastewater from different sources. Among the constructed wetlands, upflow types of constructed wetlands have become a common selection of wastewater during the last decade. We conducted a pilot scale study at peen house on treating potential of nutrients by upflow vegetated filter(UVF) pilot wetland which was combined with hydrodynamic separator and used the cattail plant(Typha angustifolia), and operated with artificial nutrients influent. This study evaluate the performances of upflow vegetated fille, in removal of nutrients. The objectives of this study were two-fold: (i) to evaluate the nutrients removal performance of pilot-scale upflow vegetated filter, filled with a mixture of perlite and soil media and planted with cattails and (ii) to design of scale-up upflow vegetated filter using Froude number. Results indicated that, under the condition of the ranges of hydraulic surface load rate were $22.7{\pm}9.6\;m^3/m^2/day$, the average removal of $COD_{Mn}$, and TN, TP were 57.5%, 40.0% and 41.5%, respectively. Computational fluid dynamics, FLUENT 6.0 program was used to predict the distribution of velocity in UVF and hydrodynamic separator. Full scale UVF was designed using the Froude number scale-up method that was assumed geomertic similarity between model and prototype. Result shows that the UVF with 3 m diameter has capacity of design sewage flowrate 75 $m^3/day$.

• Microbiology and Biotechnology Letters
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• v.39 no.2
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• pp.133-139
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• 2011

In this study, we determined the changes in microbial numbers in solar salts according to the manufacturing process and storage duration. The salt samples were harvested from salt farms in Shinan (area 2) and Yeonggwang (area 1). They were serially diluted ten-fold and then placed on 4 kinds of cultivable media (mannitol salt agar, eosin methylene blue, plate count agar, and trypticase soy agar). After incubation, we obtained 62 halophilic isolates from the salt samples. Coliform and general bacteria were not detected in all salt samples. By 16S rRNA sequencing analysis, we found 12 kinds of halophilic bacteria belonging to the genera Halobacillus, Halomonas, Bacillus, Idiomarina, Marinobacter, Pseudoalteromonas, Vibrio, Salinivibrio, Virgibacillus, Alteromonas, Staphylococcus and some un-known stains. In our study, we discovered two novel species that have a 16S rDNA sequence similarity below 97%.

• Journal of the Korean Society of Radiology
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• v.15 no.2
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• pp.165-171
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• 2021

To prevent the secondary hospital-acquired infection (cross-infection) from occurring in the general radiographic room in the department of radiology, the microbial measurement was conducted at the points making direct close contact with radiologists and patients. For the case of radiologists, the microbial measurement and incubation were focused on the x-ray tube handle of the radiation generating device, and, for the case of patients, the microbial measurement and incubation were focused on the chin supporting device, chest-contact point, and handle. Once disinfected with Aniosurf, the sterilized media were gathered and identified, and the microorganisms were confirmed. Based on the identification results, it was confirmed that the points making direct close contact with radiologists showed a value of 103 CFU for Proteus mirabilis, Staphylococcus epidermidis, Bacillus spp. and Candida spp., and that the points making direct close contact with patients showed a value of 103~5 CFU for Proteus mirabilis, Enterococcu faecium, Pseudomonas aeruginosa, NTM(Non-Tuberculosis Mycobacteria) and Candida spp.. It was also confirmed that the types and number of microorganisms gathered from the points making direct close contact with patients were greater. Fortunately, most of the involved microorganisms were observed to be on the skin surface and are known to become extinct when disinfected in accordance with the hospital-acquired infection control rules. However, since even minor exposure to such microorganisms may be lethal for patients with reduced immunity, caution must be taken. In particular, since the points making contact with patients showed a high level of microbial measurement, it was thought that it would be necessary for radiologists and personnel having frequent access to strictly disinfect the parts, such as instruments and handles, making frequent contact with patients. The purpose of this study was to announce the importance of safe microbial control in the radiographic inspection room in hospital, and this study is expected to be used as the baseline data for preventing hospital-acquired secondary infection and Nth infectious diseases.

• Journal of Environmental Health Sciences
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• v.50 no.2
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• pp.93-101
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• 2024

Background: As pollutants caused by non-point sources flow into rivers, river water quality monitoring for fecal pollution is becoming increasingly important. Objectives: This study was conducted to investigate the distribution of microbial communities in the Yeongsangang River water system and sewage treatment plants in Gwangju and to evaluate their antibiotic resistance. Methods: In the experiment, samples were distributed to five selective media at each point and then cultured for 18 to 24 hours. When bacteria were observed, they were sub-cultured by size and shape and identified using MALDI-TOF MS equipment. When identification was completed, 17 types of antibiotic susceptibility tests were performed using VITEK II equipment, focusing on gram-negative dominant species among the identified strains. Results: During the study period, a total of 266 strains were isolated from 39 samples. Gram-positive bacteria were 37 strains in four genera, or 13.9% of the total, and Gram-negative bacteria were 229 strains in 23 genera, or 86.1% of the total. Antibiotic susceptibility testing of 23 strains, the major dominant species, showed that one strain (4.3%) was resistant to only one antibiotic, and two strains (8.7%) were 100% susceptible to the 17 antibiotics tested. The other 20 strains (87.0%) were multidrug resistant bacteria resistant to two or more antibiotics. There were various types of multidrug resistance. Among them, penicillin and cephalosporin series showed the highest resistance. Conclusions: Based on the results of this study, it was found that the bacterial community structure changed according to regional and environmental factors, and it was judged that continuous research such as genetic analysis of antibiotic-resistant bacteria present in natural rivers is necessary.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.7
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• pp.991-996
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• 2003

Determination of regional microbial contamination in the process of rice rolled in dried laver (Kimbab) and effects of gamma irradiation on the improvement of hygienic quality and shelf stability were investigated. Total aerobic bacterial distribution of raw materials of Kimbab were; 10$^{6}$ ∼10$^{7}$ CFU/g in dried laver, 10$^3$ CFU/g in cucumber and below 10 CFU/g in steamed rice, ham, fried egg, and salted radish. Total coliform bacteria were 10$^3$ CFU/g in dried laver and detected below detection limit (10 CFU/g) in other raw materials. And it was arithmetically calculated that the levels of total aerobic bacteria and coliform bacteria in Kimbab does not exceed 10$^{5}$ CFU/g and 10$^1$ CFU/g under the aseptic process, respectively. However, microbial contamination levels in just prepared Kimbab in a market were about 10$^{6}$ CFU/g of total aerobic and coliform bacteria. Therefore, it was considered that microbial contamination of Kimbab is mainly originated from environmental uptake during the preparation. The representative media for putrefying bacterial growth were steamed rice. Coliform bacteria were mainly increased in ham and fried egg during storage. The bacteria in dried laver were radio-resistant and survived at 3 kGy of gamma irradiation. Coliform bacteria on EMB agar plate were eliminated at the dose of 2 kGy. The sensory acceptability of 2 kGy irradiated Kimbab was stable and the Kimbab can be preserved for 24 hour at 15$^{\circ}C$. Therefore, it was considered that optimal irradiation dose for radicidation of Kimbab was 2 kGy.

• The Korean Journal of Mycology
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• v.24 no.2 s.77
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• pp.111-126
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• 1996

Transfer of the isolated nuclei from Lentinus edodes into protoplasts of Pleurotus florida was induced with polyethlene glycol (PEG) and $CaCl_2$. The intergeneric transfer products were classified into nuclear hybrid, heterokaryon or synkaryon, and reconstituted cell. These progenies except nuclear hybrids formed mature fruiting bodies on sawdust rice bran medium. Formation of fruit bodies was influenced by several factors such as light, temperature, nutrition and physic state of the culture media. Most of fruiting body characters were similar to those of P. florida in synkaryon and L. edodes in reconstituted cell, respectively. All these basidiocarps had clamp connections though initial heterokaryon colonies were lacking. Isozyme patterns of intergeneric progenies were quite different from those of parents. DNA polymorphisms of transfer products were also compared by random amplified polymorphic DNAs (RAPD) analysis based on polymerase chain reaction. The RAPD patterns were different from those of donor and recipient. DNA fingerprints ranged in size from 0.25 to 4.0 Kb. On the basis of RAPD, the transfer products were classified into five groups. Two synkaryon were analysed with distribution of progenies and segregation of genetic markers by random spore analyses. The genetic markers were segregated into wild type and riboflavine requiring auxotrophs.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.3
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• pp.317-324
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• 2010

Metal-supported solid oxide fuel cells (SOFCs) have been developed to commercialize SOFCs. This new type of SOFC has high mechanical strength, but its mass transfer rate may be low due to the presence of a contact layer. In this study, the mass transfer characteristics of an anode-supported SOFC and a metal-supported SOFC are studied by performing numerical simulation. Governing equations, electrochemical reactions, and ceramic physical-property models are determined simultaneously; molecular diffusion and Knudsen diffusion are considered in mass transport analysis of porous media. The experimental results are compared with simulation data to validate the results of numerical simulation. The average current density of the metal-supported SOFC is 23% lower than that of the anode-supported SOFC. However, because of the presence of the contact layer, the metal-supported SOFC has a more uniform distribution than the anode-supported SOFC.

• Journal of Mushroom
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• v.16 no.4
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• pp.299-303
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• 2018

Flammulina velutipes, which is a white rot fungus, is a commercially important edible mushroom and is produced in large quantities with the help of an automated and mechanized cultivation system in Korea. F. velutipes has the lowest distribution rate among domestic cultivars, estimated at about 20 percent. As most white cultivars of F. velutipes produced and exported to Korea were introduced from Japan, farmers pay large amounts of royalties. Therefore, we have developed a new, purely domestic cultivar, "Baeke," to substitute for Japanese cultivars, which has improved storage characteristics for export. Baeke was bred by mating two monokaryotic strains isolated from ASI 4216-18 (Hansol) and ASI 4217-26 (Baekjung). Baeke showed faster mycelial growth and higher mycelial density upon incubation for seven days at $25^{\circ}C$ on PDA media than the control variety. The mycelial growth of Baeke was even maintained at $30^{\circ}C$ unlike the control. The lengths of pilei and stipes in Baeke harvested in the optimal stage were $11.2{\pm}0.5mm$ and $125{\pm}5.4mm$, respectively, and they were $11{\pm}0.5mm$ and $141.9{\pm}5.7mm$, respectively, in the control harvested in the optimal stage. The yields of Baeke ($257.4{\pm}13.5g$) and control ($270.7{\pm}17.8g$) per 1,100ml in bottle cultivation showed no significant difference. Overall, our results showed that Baeke was at par with foreign varieties of Flammulina velutipes in terms of quality and yield and had a uniformly shaped fruitbody, which added to its commercial value.

• Trans-
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• v.5
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• pp.1-27
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• 2018

What is 'analyzing a movie'? And, what is 'its role in film studies'? The question required a systematic and scholarly answer, and filmologie was making a clear place for itself. Through psychology, aesthetics, text theories and of course semiotics, the conceptualization of 'film' has been formed. Deleuze, who has been continually writing about 'movies' in his philosophical essays, ended the debate in defining the relationship between 'image and essence' when he released 《Movie 1, Movement-Image》 in 1983. 'Film' rapidly became the topic of the century and became a 'device' that leads the way of thinking. The reason why Jean-Louis Boissier labeled this 'film' as 'device (le dispositif)' was not part of film studies. What should be noted is that the mention of 'film' became a key part of the debate of 'reproduction', which was the most popular subject of philosophy and humanities. In the digital era, the film is once again questioned about its definition. In retrospect, themes of core debates of 'History of cinema' have always been driven by simple and superficial technological changes. With the emergence of CG (Computer Graphics), the question of 'cinema' in the 21st century is not only a philosophical discussion on the problem of 'reproduction', but also a crucial change that shifted the focus of the debate on the nature of the film from 'production' to 'distribution'.

• Journal of the Korean earth science society
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• v.35 no.1
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• pp.29-40
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• 2014

A DC resistivity survey was performed to detect anomalies beneath concrete pavement. A set of high conductive media and planar electrodes were used to lessen the effect's a high contact resistance of concrete. Results of the resistivity survey were analyzed and compared with those of other geophysical surveys such as Ground Penetration Radar (GPR), Impulse Response (IR), and Multi-channel Analysis of Surface Waves (MASW), which were carried out in the same location. The results of resistivity survey showed a high resistive distribution in the section of sink and pavement where a pattern of reinforcement was observed through the GPR survey. Also, a comparison of results between the IR and resistivity surveys indicated that the high resistivity was produced by the high dynamic stiffness in the reinforced section. The co-Kriging of both the results of DC resistivity and MASW surveys at the same location showed that an integrated geostatistical analysis is able to give more accurate description on the anomalous subsurface region than can a separate analysis of each geophysical approach. This study suggests that the integrated geostatistical approaches were used for a decision-making process based on the geophysical surveys.