• Food Science and Preservation
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• v.15 no.5
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• pp.642-647
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• 2008

This study investigated the microbiological and sensory characteristics of Kongnamul muchim stored with gamma-irradiated red pepper powder at $4^{\circ}C$. Total aerobic microbes in raw Kongnamul muchim were 5.72 log CFU/g in the red pepper powder and 2.40 log CFU/g in the garlic used during storage, but were not detected n other raw materials. Coliform bacteria and fungi were found, at 3.11 and 3.48 log CFU/g respectively, only n the red pepper powder. Microorganisms in Kongnamul muchim stored with gamma-irradiated (10 kGy) red pepper owder were not detected over 3 days of storage at $4^{\circ}C$. The pH, Hunter's color value, and sensory characteristics id not change significantly on storage. These results suggest that the addition of gamma-irradiated (less than 10 Gy) red pepper powder could improve the microbiological safety of Kongnamul muchim without changing desirable ensory characteristics.

• Journal of Food Hygiene and Safety
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• v.28 no.1
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• pp.19-23
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• 2013

A simple and rapid method has been developed and validated for simultaneous determination of each macrolides residues (spiramycin, josamycin, tilmicosin, tylosin) in chicken muscle by high-performance liquid chromatography- photo diode array (HPLC-PDA). Chicken muscle sample have been extracted with liquid-liquid extraction process; analytes was extracted by acetonitrile, and then defatted with hexane saturated by acetonitrile. The HPLC separation was performed on a Unison UK-$C_{18}$ ($150mm{\times}3.0mm$, $3{\mu}m$) with a gradient system of 0.1% trifloroacetic acid (TFA) and 0.1% trifloroacetic acid (TFA) in acetonitrile as the mobile phase. The drugs were detected at 232 nm for spiramycin and josamycin, and 287 nm for tilmicosin and tylosin. The limits of quantification (LOQs) were between 27 and $59{\mu}g/kg$; and the intra- and inter-day precision (relative standard deviation; RSD) was between 0.9-13.2 and 2.4-13.1%, respectively in chicken muscle sample. The method may has been successfully applied for multiresidue determination of four macrolides below the maximum residue limits (MRLs) established by the European Union (EU).

• Korean Chemical Engineering Research
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• v.54 no.5
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• pp.678-686
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• 2016

The effect of internal and shroud nozzle distributor to bubbling fluidized beds which has the size of $0.3m-ID{\times}2.4m-high$ column was modeled by CPFD (Computational Particle-Fluid Dynamics). Metal-grade silicon particles (MG-Si) were used as bed materials which have $d_p=149{\mu}m$, ${\rho}_p=2,325kg/m^3$ and $U_{mf}=0.02m/s$. Total bed inventory and static bed height were 75 kg and 0.8 m, respectively. Effect of vertical internal on the bubble rising velocity was investigated. Bubbles were split by internal when the axial position of the internal from the distributor, z = 0.45 m. Bed pressure drop and axial solid holdup were not affected by internal. However, in the case that axial distance of internal from distributor was too close to jet penetration length, bubbles were not separated and bypassed internal, and faster than without internal or z = 0.45 m.

• Applied Chemistry for Engineering
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• v.5 no.1
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• pp.160-175
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• 1994

Fibrous potassium hexatitanate whisker with the size of $ID=0.5{\sim}1{\mu}m$ and length=$100{\sim}1000{\mu}m$ (aspect ratio=100~1000) was produced through the reaction between titanium dioxide and potassium carbonate using the slow-cooling calcination followed by water leaching treatment. The optimum condition for the production of fibrous potassium titanate was calcination temperature of $1100^{\circ}C$ for 5hrs, $TiO_2$ mole ratlo to $K_2CO_3$ of 4.5 and slow-cooling rate of $0.5^{\circ}C/min$ to $860^{\circ}C$. Fibrous crystal are grown by the association between the solid potassium titanate and liquid phase during the slow-cooling process. The Proper water leaching condition for removing of K component was leaching time of 10hrs in boiling water. Pressurizing of the mixture of $K_2CO_3$ and $TiO_2$ to be calcinated became effective on the growth of fibrous crystal.

• Journal of the Korean association of regional geographers
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• v.18 no.3
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• pp.326-335
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• 2012

The purpose of this study id to identify service quality of national stone culture festival, to find relationship service quality to festival satisfaction and after behavioral intention of festival participants. To achieve the purpose of this study, 13 elements of service quality was chosen through previous literature study. And 3 factors were extracted by 1st factor analysis, these are hardware, software, and humanware factor. And second factor analysis was performed to identify validity and reliability these factors. And 5th hypothesis was established and adopted in three hypothesis. That is Hardware service quality factor have a influence to festival satisfaction of participants, festival satisfaction of participants have a influence to revisitation and recommendation intention. This paper indicates that results of this study is useful to regional festival planning to settle down as a sustainable events, necessary to retain service quality and satisfaction as a precedent condition.

• Childhood Kidney Diseases
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• v.7 no.1
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• pp.52-59
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• 2003

Purpose : The renin-angiotensin system(RAS) plays an important role in renal growth and development. We have studied the prevalence of renal anomalies and documented the association between karyotype and renal anomalies using IVP and ultrasonography. Furthermore, to investigate the impact of RAS gene polymorphism on renal anomaly in Turner syndrome, we examined the ACE I/D genotype, angiotensinogen(AGT) gene M235T, angiotensin receptor type 1(ATR) gene A1166C. Methods : Cytogenetic analysis was performed in 33 Turner syndrome patients on peripheral blood lymphocytes. Ultrasonography(US) of the kidneys and collecting system and intravenous pyelography(IVP) were perfomed in all patients. Nuclear scintigraphy{Tc 99m dimercaptosuccinic acid(DMSA) scan} was also performed for the definite renal diagnosis if indicated. And, ACE I/D genotype, angiotensinogen(AGT) gene M235T, angiotensin receptor type 1(ATR) gene A1166C were examined by PCR amplification of genomic DNA samples. Results : The prevalence of renal anolmalies in Turner syndrome was 36.4%(12/33). The Karyotype 45, X was observed in 18 of the 33 girls(54.5%), of whom 8(44.4%) had renal anomalies. Mosaic karyotypes were observed in 11(33.3%) and four(12.2%) had a non-mosaic structural aberration of the X chromosome. In this group 4(25.7%) had renal anomalies. More renal anomalies were associated with the 45, X karyotype than those with mosaic/structural abnormalities of X chromosome, but the difference was not statistically significant(P>0.05). And, there was no significant differences in the RAS gene polymorphism and allele frequencies between renal anomaly group and normal group in Turner syndrome. Conclusion : The prevalence of renal anolmalies in Turner syndrome was 36.4%. There is no significant differences in the RAS gene polymorphism and allele frequencies between the renal anomaly group and the normal group in Turner syndrome.

• Journal of Life Science
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• v.32 no.4
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• pp.310-317
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• 2022

Recently, interest in the harmful factors of particulate matter (PM), a major component of air pollution, has been increasing. In particular, PM_2.5 with a diameter of less than 2.5 ㎛ is well known to induce oxidative stress accompanied by autophagy in human lung epithelial cells. However, studies on whether PM_2.5 increases autophagy under oxidative stress and whether this process is reactive oxygen species (ROS)-dependent are insufficient. Therefore, in this study, we investigated whether PM_2.5 promotes autophagy through the generation of ROS in human alveolar epithelial A594 cells. According to our results, cells co-treated with PM_2.5 and hydrogen peroxide (H₂O₂) showed a lower cell viability than cells treated with each alone, which was associated with increased total and mitochondrial ROS production. The co-treatment of PM_2.5 and H₂O₂ also increased autophagy induction, which was confirmed through Cyto-ID staining, and the expression of autophagy biomarker proteins increased. However, when ROS generation was artificially blocked by N-acetyl-L-cysteine pretreatment, the reduction in cell viability and induction of autophagy by PM_2.5 and H₂O₂ co-treatment were markedly attenuated. Therefore, the present results suggest that PM_2.5-induced ROS generation may play a critical role in autophagy induction in A549 cells.

• The Journal of Society for e-Business Studies
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• v.20 no.1
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• pp.217-241
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• 2015

One of the challenges in online community management is what level of perceived anonymity can be granted to encourage active participation from members while discouraging unhealthy activities. Few studies developed a scheme of anonymity and investigated how different levels of anonymity influence community activities. This study develops a classification scheme of anonymity encompassing the following three different levels : (1) real name(no anonymity), (2) nickname (partial anonymity), and (3) random assignment of a temporal ID (complete anonymity). Then, it examines how different levels of anonymity influence trust and perceived risk, which in turn affect virtual team performance. A series of laboratory experiments were performed, manipulating the levels of anonymity, in the context of well-structured communities that allow prior interactions among community members. The data was collected from 364 laboratory participants and analyzed using ANOVA and PLS. The results indicate that the difference of anonymity between (2) and (3) had not be significant and the only (1) could not guarantee the anonymity. The impact of anonymity on trust and perceived risk could not be significant in this situation. These findings could contribute to make more beneficial member identification strategies in online community practice.

• Journal of Internet Computing and Services
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• v.21 no.3
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• pp.29-39
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• 2020

Online communities, such as Internet portal sites and social media, have become popular since they allow users to share opinions and to obtain information anytime, anywhere. Accordingly, an increasing number of opinions are manipulated to the advantage of particular groups or individuals, and these opinions include falsified product reviews and political propaganda. Existing detection systems are built upon the characteristics of manipulated opinions for one particular time period. However, manipulation tactics change over time to evade detection systems and to more efficiently spread information, so detection systems should also evolve according to the changes. We therefore propose a system that helps observe and trace changes in manipulation tactics. This system classifies opinions into clusters that represent different tactics, and changes in these clusters reveal evolving tactics. We evaluated the system with over a million opinions collected during three election campaigns and found various changes in (i) the times when manipulations frequently occur, (ii) the methods to manipulate recommendation counts, and (iii) the use of multiple user IDs. We suggest that the operators of online communities perform regular audits with the proposed system to identify evolutions and to adjust detection systems.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.2
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• pp.85-90
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• 2012

In this paper, we compared and analyzed 3D silicon-oxide-nitride-oxide-silicon (SONOS) multi layer flash memory devices fabricated on nitride or oxide layer, respectively. The device fabricated on nitride layer has inferior electrical properties than that fabricated on oxide layer. However, the device on nitride layer has faster program / erase speed (P/E speed) than that on the oxide layer, although having inferior electrical performance. Afterwards, to find out the reason why the device on nitride has faster P/E speed, 1/f noise analysis of both devices is investigated. From gate bias dependance, both devices follow the mobility fluctuation model which results from the lattice scattering and defects in the channel layer. In addition, the device on nitride with better memory characteristics has higher normalized drain current noise power spectral density ($S_{ID}/I^2_D$>), which means that it has more traps and defects in the channel layer. The apparent hooge's noise parameter (${\alpha}_{app}$) to represent the grain boundary trap density and the height of grain boundary potential barrier is considered. The device on nitride has higher ${\alpha}_{app}$ values, which can be explained due to more grain boundary traps. Therefore, the reason why the devices on nitride and oxide have a different P/E speed can be explained due to the trapping/de-trapping of free carriers into more grain boundary trap sites in channel layer.