• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.1
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• pp.17-25
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• 1996

The results identified for bacterial flora 174, Vibrio spp.132, and coliform group 183 strains isolated from the areas of last China Sea and Yosu coastal sea during from August 6th. to 14th. 1992 were as follow: 40 strains among the 74 strains of bacteria flora isolated from fast China sea area were Pseudomonas spp.$(54\%)$ and 60 strains among the 100 strains isolated from Yosu sea area were Enterobacteriaceae $(60\%)$. Four strains were Vibrio alginoliticus and one strain of V, parahaemolyticus among 5 strains of genus Vibrio isolated from last China Sea. While 54 strains were V. alginolyticus $(43\%)$ and V, parahaemolyticus $(17\%)$ among 127 strains genus Vibrio isolated from Yosu coastal sea area. Seventy nine strains among the 156 strains of coliform group isolated from Vosu sea area were Escherichia coli I $(51\%)$ and each one strain Citrobacter freundii I and II. 3 strains among 27 strains isolated from last China sea area were E. coli$(11\%)$ and 1 strain of C. freundii I. Coliform group was grouped into 16 types by IMViC system, $44^{\circ}C$, gelatin liquefaction test.

• Reproductive and Developmental Biology
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• v.35 no.4
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• pp.479-483
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• 2011

The objective of this study was to determine the effects of E. coli isolated from porcine semen on sperm viability, motility, and semen pH. Semen samples were prepared using commercial extender, $Seminark^{Pro}$ (Noahbio Tech, Korea) that did not contain antibiotics. And 4 different levels of E. coli were artificially innoculated to semen with following concentrations; 4,000 of sperms with 1 of E. coli (T1), 400 with 1 (T2), 40 with 1 (T3), and 4 with 1 (T4). Semen samples were preserved at $17^{\circ}C$ for 5 days in semen storage box until analyzed by flowcytometer. Aliquots were subjected to measure the sperm viability (Live/$Dead^{(R)}$ stain), motility (mitochondrial function), and semen acidity (pH) from day 0 (day of semen collection) to day 5. Sperm motility and viability were significantly decreased (p<0.05) on day 0 (4 hrs after preservation at $17^{\circ}C$) in T3 and T4 compared to control groups and were significantly decreased (p<0.05) in all groups from day 3. Sample pH was acidic in T3 (6.90~6.86) and T4 (6.86~6.65) from day 3 to day 5 (p<0.05). On the other hand, sample pH was maintained 7.0~7.1 in control, T1, and T2 during the experimental period. Sperm motility and viability were significantly decreased from day 0 to day 5 compared to control in samples contaminated with E. coli above a value of 40:1 ($20{\times}10^6$ sperm cells/ml : $5{\times}10^5$ cfu/ml). Even on day 1 in T4 and on day 3 in T3, semen pH was acidic probably due to the acidification of dead spermatozoa. These results suggest that E. coli contamination has a concentration-dependent detrimental effect on extended porcine semen quality.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.7
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• pp.37-48
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• 2014

Wireless mesh networks have emerged as a key technology in environment that needs wireless multi-hop communication without infrastructure and IEEE 802.11s mesh network standard have currently been established. One of big differences between this standard and the legacy IEEE 802.11 is that MCCA MAC is included to support QoS. MCCA supports bandwidth reservations between neighbors, so it can satisfy the QoS of bandwidth guarantee. However, MCCA has dis-advantages as follow; 1) it can not guarantee end-to-end bandwidth, 2) in multi-interface multi-channel wireless environments, the IEEE 802.11s does not provide a bandwidth reservation protocol and a wireless channel assignment etc. In this paper, we have proposed MIMC R-HWMP, which expands R-HWMP that was proposed in our previous work[3], to support multi-interface multi-channel. By simulation, we showed end-to-end bandwidth guarantee and the increase in the available bandwidth in multi-interface multi-channel wireless mesh networks.

• The Journal of the Convergence on Culture Technology
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• v.6 no.1
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• pp.171-178
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• 2020

Amid public's growing interest on garden and more leisure time of modern life-style, there is an effort by the government to utilize forest as public garden. In order to utilize forests as pubic garden, a new concept of "Forest Garden" should be defined and introduced first. Furthermore, introducing a new concept requires academically analyzing values of a new concept before a new concept is widely used. Thus, we aimed to clarify the concept of forest garden by conducting Delphi technique research and factor-analysis of survey results. More specifically, delphi technique research was conducted to extract composition elements and explanation elements of forest garden. Factor analysis was conducted on the top 25 elements and 5 values were extracted as a result. They are form, scenery, ecology, history/cuture and usefulness which are essential values required of forest garden. Forest garden should have all of 5 values and be capable of function as both forest and garden which would also need continuous maintenance. We believe this study is the first one to establish definition of forest garden and more specific and realistic definitions need to be built through continuous research, 000 experiment and on-site evaluation. We also believe that this study will serve as foundation for further efforts in building forest garden in various space and in defining proper concept of forest garden.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.11 s.114
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• pp.1073-1081
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• 2006

In this paper, a phased array antenna based on thin-film dielectric technology at 60 GHz is designed. In order to reduce dividing/combining loss and avoid high loss of phase shifters, Rotman Lens has been employed as a feeder of antenna. The lens has 3 beam ports and 5 array ports with 2 dummy ports. The simulation for the design was performed by simulator using MoM(method of moments). The measured results of fabricated lens show magnitude deviation less than ${\pm}2dB$ and phase aberration less than ${\pm}5^{\circ}$ over $58{\sim}62GHz$. The antenna shows ${\pm}7^{\circ}$ of scan angles.

• Journal of radiological science and technology
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• v.39 no.1
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• pp.43-49
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• 2016

In this study, equivalent dose and LET (Linear Energy Transfer) calibration of CR-39 SSNTD (Solid State Nuclear Track Detector) were performed using 400 MeV/u C heavy ions in HIMAC (Heavy Ion Medical Accelerator in Chiba) for high LET radiation therapy. The irradiated CR-39 SSNDTs were etched according the etching condition of JAXA (Japan Aerospace Exploration Agency). And the etched SSNTDs were analyzed by using Image J. Determined frequency mean dose (${\bar{y_D}}$)and dose-mean lineal energy (${\bar{y_F}}$)of 400 MeV/u C are about 8.5keV/mm and 10.1 keV/mm, respectively by using the CR-39 SSNTD. This value is very similar to the results calculated by GEANT4 Monte Carlo simulation and measured with TEPC (Tissue Equivalent Proportional Counter) active radiation detector. We could determine the equivalent dose and LET calibration factors of CR-39. And we confirmed that the CR-39 SSNTD was useful for high LET radiation dosimetry in hadron radiotherapy.

• Korean Journal of Veterinary Service
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• v.43 no.2
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• pp.79-88
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• 2020

The aim of this study was to investigate the prevalence of CTX-M β-lactamase and plasmid-mediated quinolone resistance (PMQR) genes, and the pattern of antibiotic resistance in cefotaxime-resistant gramnegative bacteria. A total 126 gram-negative bacteria were isolated from hospitalized dogs and cats between 2018 and 2019. The most predominant isolates were E. coli (n=41), followed by Pseudomonas aeruginosa (n=25), Proteus mirabilis (n=14), Klebsiella pneumoniae (n=9), Sphingomonas paucimobilis (n=7), and Enterobacter cloacae and Serratia marcescens (respectively, n=5). Cefotaxime-resistant isolates were identified in 26.2% (33 isolates) of 126 gram-negative bacteria. CTX-M type β-lactamase were found in 15 isolates (10 E. coli, 1 Ent, cloacae and 4 K. pneumoniae, respectively). Among the CTX-M producing gram-negative bacteria, CTX-M-1 and CTX-M-9 were detected in 10 (66.7%) and 5 (33.3%) isolates, respectively. While, CTX-M-2 and CTX-M-8 were not found. PMQR genes were detected in 12 (36.4%) isolates (4 E. coli, 2 Ent, cloacae and 6 K. pneumoniae, respectively), and the predominant PMQR gene was aac(6')-lb-cr (n=9), followed by qnrB (n=8) and qnrS (n=1) alone or in combination. qnrA and qepA were not found. Additionally, 9 (60%) of 12 PMQR positive isolates were co-existence with CTX-M-1 or CTX-M-9. CTX-M or PMQR producing isolates showed highly resistance to penicillins (100%), cephalosporins (100~66.7%), monobactams (72.2%), and non-β-lactam antibiotics (94.4~61.1%) such as quinolones, trimethoprim/sulfamethoxazole, tetracycline and gentamicin. These findings showed CTX-M-1, CTX-M-9, aac(6')-lb-cr and qnrB were highly prevalent in cefotaxime-resistant Enterobacteriaceae isolates from companion animals in our region. Moreover, PMQR genes were closely associated with CTX-M type β-lactamase.

• Safety and Health at Work
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• v.7 no.2
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• pp.156-160
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• 2016

Background: Workers in pesticide manufacturing industries are constantly exposed to pesticides. Genetic biomonitoring provides an early identification of potential cancer and genetic diseases in exposed populations. The objectives of this biomonitoring study were to assess DNA damage through comet assay in blood samples collected from industry workers and compare these results with those of classical analytical techniques used for complete blood count analysis. Methods: Samples from controls (n = 20) and exposed workers (n = 38) from an industrial area in Multan, Pakistan, were subjected to various tests. Malathion residues in blood samples were measured by gas chromatography. Results: The exposed workers who were employed in the pesticide manufacturing industry for a longer period (i.e., 13-25 years) had significantly higher DNA tail length ($7.04{\mu}m$) than the controls ($0.94{\mu}m$). Workers in the exposed group also had higher white blood cell and red blood cell counts, and lower levels of mean corpuscular hemoglobin (MCH), MCH concentration, and mean corpuscular volume in comparison with normal levels for these parameters. Malathion was not detected in the control group. However, in the exposed group, 72% of whole blood samples had malathion with a mean value of 0.14 mg/L (range 0.01-0.31 mg/L). Conclusion: We found a strong correlation ($R^2=0.91$) between DNA damage in terms of tail length and malathion concentration in blood. Intensive efforts and trainings are thus required to build awareness about safety practices and to change industrial workers' attitude to prevent harmful environmental and anthropogenic effects.

• Safety and Health at Work
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• v.10 no.2
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• pp.229-236
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• 2019

Background: Emerging reports suggest the potential for adverse health effects from exposure to emissions from some additive manufacturing (AM) processes. There is a paucity of real-world data on emissions from AM machines in industrial workplaces and personal exposures among AM operators. Methods: Airborne particle and organic chemical emissions and personal exposures were characterized using real-time and time-integrated sampling techniques in four manufacturing facilities using industrial-scale material extrusion and material jetting AM processes. Results: Using a condensation nuclei counter, number-based particle emission rates (ERs) (number/min) from material extrusion AM machines ranged from $4.1{\times}10^{10}$ (Ultem filament) to $2.2{\times}10^{11}$ [acrylonitrile butadiene styrene and polycarbonate filaments). For these same machines, total volatile organic compound ERs (${\mu}g/min$) ranged from $1.9{\times}10^4$ (acrylonitrile butadiene styrene and polycarbonate) to $9.4{\times}10^4$ (Ultem). For the material jetting machines, the number-based particle ER was higher when the lid was open ($2.3{\times}10^{10}number/min$) than when the lid was closed ($1.5-5.5{\times}10^9number/min$); total volatile organic compound ERs were similar regardless of the lid position. Low levels of acetone, benzene, toluene, and m,p-xylene were common to both AM processes. Carbonyl compounds were detected; however, none were specifically attributed to the AM processes. Personal exposures to metals (aluminum and iron) and eight volatile organic compounds were all below National Institute for Occupational Safety and Health (NIOSH)-recommended exposure levels. Conclusion: Industrial-scale AM machines using thermoplastics and resins released particles and organic vapors into workplace air. More research is needed to understand factors influencing real-world industrial-scale AM process emissions and exposures.

• The Journal of the Convergence on Culture Technology
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• v.8 no.5
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• pp.561-568
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• 2022

The purpose of this study is to explore the narrative of VR disaster and safety Education introduced by disaster film narrative. VR(Virtual Reality) is be suitable technology for disaster and safety Education due to media characteristics as 'immersion', 'presence', 'interactivity', 'pleasure'. Disaster film narrative is able to be worth VR disaster and safety education as a variety of stories and educational effect. For this study, examine a theoretical study and a visiting research of 'Busan 119 Safety & Experience Center'. This study concludes that Firstly need to introduce catharsis effect, Secondly, build 'interactive narratives' that ensure active participation of users, Thirdly, introduce an 'adventure game' narrative element, Fourthly, introduce a hero-shaped narrative in which the user becomes a one-man hero, And lastly, need education as use user's multiple access and group experience learning. Therefore, This thesis is of academic value in that it suggest a desirable new direction of narrative in VR disaster and safety education.