• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.5
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• pp.662-669
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• 2022

The purpose of this study is to test the effects of electrolyzed water treatment on dried-laver Pyropia sp. processing facilities to control microbial contamination. Following the progression of the process to the next step, as well as during the lapse between process operating hours, the contamination level of total viable cell counts (TVC) and total coliform (TC) of laver increased. The TVC increased during the aging step, and after the molding-drying steps were completed, it increased by approximately 2.0 log CFU (colony forming unit)/g. Freshwater used for processing in April had a TVC of 4.31 log CFU/mL, which was more polluted than 2.61 log CFU/mL of seawater. Electrolyzed water was used to treat the sponge used in the laver-molding process, which resulted in a 2 log CFU/mL decrease.The TVC of dried-laver decreased by 1 to 2 log CFU/g when electrolyzed water was applied to the process. In conclusion, application of electrolyzed water in dried-laver processing was shown to be effective in reducing the microbiological contamination of the final product.

• Journal of the FoodService Safety
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• v.3 no.1
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• pp.38-44
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• 2022

This study investigated the microbiological hazards in the manufacturing processes of Naengmyeon. Sanitary indicative bacteria, such as aerobic plate counts and coliforms as well as pathogenic bacteria, were examined from raw materials, manufacturing processes, working area, 17 utensils and equipment. The aerobic plate counts for raw materials and arrowroot starch estimated as 0.77±0.68~5.02±0.28 and 5.02±0.28 log CFU/g, respectively. Coliforms were detected from wheat flour, buckwheat flour, and potato starch. Staphylococcus aureus was detected to be 0.61±1.06 log CFU/g in wheat flour and 0.20±0.35 log CFU/g in buckwheat flour. During the manufacturing process, aerobic plate counts for kneading process were 4.54±0.34 log CFU/g. But after the press out and heat process, contamination of aerobic plate counts and coliforms decreased and remained at a low level until the release process. Aerobic plate counts before washing disinfection of screw were 3.28±0.62 log CFU/100 cm², the level of which was high in utensils and equipment that had contact with employees or water. These results represent not only an important indicator for the hygienic level but also a scientific basis for analyzing biological hazards, which lead to the introduction of HACCP for the production of safe and hygienic cold noodles processed by manufacturers.

• Food Science and Preservation
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• v.11 no.4
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• pp.530-537
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• 2004

This study was conducted to determine the inactivation effect of electrolyzed water and organic acids either alone or in combination on L. monocytogenes or natural microflora on lettuce. Acidic electrolyzed water completely inactivated L. monocytogenes in broth system within 60 sec, but alkalin electrolyzed water caused approximate 1.7 log CFU/g reduction. However, acidic electrolyzed water reduced only 2.5 log CFU/g of L. monocytogenes on lettuce, and similar antimicrobial effect was observed with alkalin electrolyzed water. In the meantime, acidic and alkaline electrolyzed water caused approximately 2 log CFU/g reduction compared to control, whereas both electrolyzed water combined with $1\%$ organic acids ranged from 2.6 to 3.7 log CFU/g reduction. Among the organic acids, both electrolyzed water combined with $1\%$ citric acid showed the strongest synergistic antimicrobial effect to reduce L. monocytogenes on lettuce as well as total counts, yeast and molds. When antimicrobials, alone or in combination were treated into L. monocytogenes inoculated lettuce at $5^{\circ}C\;and\;15^{\circ}C$ for designed periods, the combined alkalin electrolyzed water with $1\%$ citric acid showed the greatest potential to inhibit growth of the bacteria. According to Scanning Electron Microscopy(SEM), the treatment of electrolyzed alkali water in combination with $1\%$ citric acid highly reduced the growth of the L. monocytogenes compared to single treatment and resulted in causing the destruction of cell membrane.

• Analytical Science and Technology
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• v.19 no.2
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• pp.131-141
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• 2006

Hydrobromic acid salt of a $N_2O_2$ tetradentate ligand, N,N'-bis(2-hydroxybenzyl)-ethylene-diamine ($H-BHE{\cdot}2HBr$) was synthesized. $Br-BHE{\cdot}2HBr$, $Cl-BHE{\cdot}2HBr$, $CH_3-BHE{\cdot}2HBr$ and $CH_3O-BHE{\cdot}2HBr$ having Br, Cl, $CH_3$ and $CH_3O$ substituents at 5-position of the phenol group of $H-BHE{\cdot}2HBr$ were also synthesized. $Nap-BHE{\cdot}2HBr$ having naphthalen-2-ol instead of the phenol group was also synthesized. The potentiometry study in aqueous solution revealed that the proton dissociations of the synthesized ligands occurred in four steps and the order of the calculated overall proton dissociation constants (${\log}{\beta}_p$) of each ligand was Br-BHE < Cl-BHE < H-BHE < Nap-BHE < $CH_3$-BHE < $CH_3O$-BHE. The order showed a similar trend to that of Hammett substituent constants(${\sigma}_P$). The order of the stability constants (${\log}K_{ML}$) was CO(II) < Ni(II) < Cu(II) > Zn(II) > Cd(II) > Pb(II). The order in their stability constants (${\log}K_{ML}$) of each transition metal complex agreed well with that of the overall proton dissociation constants (${\log}{\beta}_p$).

• Geophysics and Geophysical Exploration
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• v.10 no.3
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• pp.183-190
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• 2007

The site effects of seismic stations were evaluated by conducting a simultaneous inversion of the stochastic point-source ground-motion model (STGM model; Boore, 2003) parameters based on the accumulated dataset of horizontal shear-wave Fourier spectra. A model parameter $K_0$ and frequency-dependent site amplification function A(f) were used to express the site effects. Once after a H/V ratio of the Fourier spectra was used as an initial estimate of A(f) for the inversion, the final A(f) which is considered to be the result of combined effect of the crustal amplification and loca lsite effects was calculated by averaging the log residuals at the site from the inversion and adding the mean log residual to the H/V ratio. The seismic stations were classified into five classes according to $logA_{1-10}^{max}$(f), the maximum level of the site amplification function in the range of 1 Hz < f < 10 Hz, i.e., A: $logA_{1-10}^{max}$(f) < 0.2, B: 0.2 $\leq$ $logA_{1-10}^{max}$(f) < 0.4, C: 0.4 $\leq$ $logA_{1-10}^{max}$(f) < 0.6, D: 0.6 $\leq$ $logA_{1-10}^{max}$(f) < 0.8, E: 0.8 $\leq$ $logA_{1-10}^{max}$(f). Implication of the classified result was supported by observing a shift of the dominant frequency of average A(f) for each classified stations as the class changes. Change of site classes after moving seismic stations to a better site condition was successfully described by the result of the station classification. In addition, the observed PGA (Peak Ground Acceleration)-values for two recent moderate earthquakes were well classified according to the proposed station classes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.11
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• pp.1632-1638
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• 2012

The effects of combined treatment of aqueous $ClO_2$ and UV-C or electron beam irradiation on microbial growth and quality in chicon during storage at $4^{\circ}C$ were investigated. Samples were treated separately with 50 ppm of $ClO_2$, 5 kJ/$m^2$ of UV-C, 2, 5, 7, and 10 kGy of electron beam irradiation, as well as a combination of $ClO_2$ and UV-C or 2 kGy of electron beam irradiation. The populations of total aerobic bacteria as well as yeast and molds in the chicon samples were determined following each treatment. The populations of total aerobic bacteria in the chicon samples decreased by 1.49~2.92 log CFU/g following combined treatment of $ClO_2$ and UV-C irradiation compared to the control, whereas the populations of yeast and molds decreased by 1.63~1.78 log CFU/g. On the contrary, following combined treatment of $ClO_2$ and electron beam irradiation, the populations of total aerobic bacteria as well as yeast and molds in the chicon samples were undetectable during storage. Color measurements indicated that Hunter $L^*$, $a^*$, and $b^*$ values were not significantly different among the treatments during storage. These results suggest that combined treatment of $ClO_2$ and electron beam irradiation can be useful for improving microbiological safety in chicon during storage.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.25 no.6
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• pp.1465-1475
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• 2015

Cheating detection models in the online games can be divided into two parts. The one is on client based model, which is designed to detect malicious programs not to be run while playing the games. The other one is server based model, which distinguishes the difference between benign users and cheaters by the server log analysis. The client based model provides various features to prevent games from cheating, For instance, Anti-reversing, memory manipulation and so on. However, being deployed and operated on the client side is a huge weak point as cheaters can analyze and bypass the detection features. That Is why the server based model is an emerging way to detect cheating users in online games. But the simple log data such as FPS's one can be hard to find validate difference between two of them. In this paper, In order to compensate for the disadvantages of the two detection model above, We use the existing game security solution log as well as the server one to bring high performance as well as detection ratio compared to the existing detection models in the market.

• Journal of Communications and Networks
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• v.16 no.2
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• pp.227-237
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• 2014

Throughput scaling laws for two coexisting ad hoc networks with m primary users (PUs) and n secondary users (SUs) randomly distributed in an unit area have been widely studied. Early work showed that the secondary network performs as well as stand-alone networks, namely, the per-node throughput of the secondary networks is ${\Theta}(1/\sqrt{n{\log}n})$. In this paper, we show that by exploiting directional spectrum opportunities in secondary network, the throughput of secondary network can be improved. If the beamwidth of secondary transmitter (TX)'s main lobe is ${\delta}=o(1/{\log}n)$, SUs can achieve a per-node throughput of ${\Theta}(1/\sqrt{n{\log}n})$ for directional transmission and omni reception (DTOR), which is ${\Theta}({\log}n)$ times higher than the throughput with-out directional transmission. On the contrary, if ${\delta}={\omega}(1/{\log}n)$, the throughput gain of SUs is $2{\pi}/{\delta}$ for DTOR compared with the throughput without directional antennas. Similarly, we have derived the throughput for other cases of directional transmission. The connectivity is another critical metric to evaluate the performance of random ad hoc networks. The relation between the number of SUs n and the number of PUs m is assumed to be $n=m^{\beta}$. We show that with the HDP-VDP routing scheme, which is widely employed in the analysis of throughput scaling laws of ad hoc networks, the connectivity of a single SU can be guaranteed when ${\beta}$ > 1, and the connectivity of a single secondary path can be guaranteed when ${\beta}$ > 2. While circumventing routing can improve the connectivity of cognitive radio ad hoc network, we verify that the connectivity of a single SU as well as a single secondary path can be guaranteed when ${\beta}$ > 1. Thus, to achieve the connectivity of secondary networks, the density of SUs should be (asymptotically) bigger than that of PUs.

• 한국지구물리탐사학회:학술대회논문집
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• 2010.10a
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• pp.189-190
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• 2010

• Journal of Digital Contents Society
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• v.12 no.2
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• pp.241-252
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• 2011

During the last decades, other parts of operating systems, storage devices, and media are changed steadily, whereas filesystem is changed little. As data is grown bigger, the number of files to be managed also increases in geometrically. Researches about new filesystem schemes are being done widely to support these files efficiently. In web document search area, there are many researches about finding meaningful documents using semantic search. Many researches tried to apply these schemes, which is been proven in web document search previously, to filesystems. But they've focused only on higher layer of filesystem, that is not related seriously to storage media. Therefore they're not well tuned to physical characteristics of new flash memory based SSD which has different features against traditional HDD. We enhance log structured filesystem, that is already well known to work better in SSD, by putting semantic search scheme to and with multi logging point.