• Journal of Korean Library and Information Science Society
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• v.45 no.4
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• pp.457-482
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• 2014

The purpose of this study is to derive a major trend through exhaustive search of papers contained in "Journal of Korean Library and Information Science Society" that has been published for 40 years. Therefore, 1,365 papers published in "Journal of Korean Library and Information Science Society" from 1974 to 2013 were analyzed. The analysis criteria include detailed subject and joint research status, research fund supporting, research area etc. The analysis results are as follows. First, as for research topics, papers on library and information science were the most, 452 papers followed by resource organization, 213 papers. The rest was found in the order of information service 188, information science 155 papers, reading guidance 101, library management 91, bibliography 84, collection development 58, archives and records management 20 papers. Through this, it was analyzed that information science is on an increasing trend while bibliography is on an decreasing trend and records management shows sluggish production. Second, as for research fund supporting, it turned out that 428 papers were funded and 315 papers among them were supported by the university while the remaining 108 papers were supported by the government. Third, joint research is on an increasing trend and unlike the fact that there have been no papers for early, papers were found to increase up to 303 papers for recent. Fourth, unlike the early phenomenon concentrated in Daegu, research areas showed even distribution throughout the country in recent years. This showed that it has grown from certain area-based academic journal to nationwide academic journal.

• Journal of Broadcast Engineering
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• v.19 no.4
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• pp.439-452
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• 2014

This paper suggests the method to extend service area by using the transmit offset delay in T-DMB single frequency network (SFN). In general, synchronization of the transmit time of all site can be done by using the reference clock of GPS, which dose not reflect the details geographical characteristics and transmit specifications of each site. Applying the site-specific transmit offset delay, we could extend the service area of SFN T-DMB. Applying the transmit offset delay, it is found that the signal quality in the region of weak receive field strength was improved and upto 4~8 km service area expansion was achieved by satisfying the minimum field strength ($45dB{\mu}V/m$) recommended by the Korea Communications Commission (KCC). Site-specific offset delay was calculated considering the geographic service area characteristics, distribution of electric field strength between neighboring sites and site-specific service target area. Experiments were carried out in order to analyze impact of calculated offset delay on the T-DMB SFN and also to confirm that the offset delay extends T-DMB service coverage. The experiment was done in metropolitan T-DMB service areas.

• Journal of Korean Tunnelling and Underground Space Association
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• v.16 no.6
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• pp.521-531
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• 2014

This paper is a study for behaviour of cavern type anchorage tunnels for suspension bridges with cable tension. Anchorage behaviour, design method for anchorage, and failure surface angle, ${\delta}$ are analyzed by comparing numerical analysis results and ultimate pullout capacities($P_u$) using bilinear corelation equation. Results show that design depths for cavern type anchorage tunnels are easily checked with linear relationships for $P/{\gamma}/H$ vs. displacement and $P_u/{\gamma}/H$ vs. H/b. The analysis results of maximum shear strain distribution and plastic status show that failure shapes are closer to circular arc model than soil cone model which frequently used. To an easy calculation of the ultimate pullout capacity, we propose a simple bilinear failure model in this study. The calculated ultimate pullout capacities from the proposed bilinear corelation equation using two failure angles results are similar to the ultimate pullout capacities from numerical analysis.

• Journal of Korea Spatial Information System Society
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• v.11 no.3
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• pp.73-78
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• 2009

100 households' survey was carried out in 2007 in Chitwan to foresee the people's livelihood and their insight into the forest conservation. This analysis revealed that households' was mainly survived with multiple livelihood categories where 98% citizens belong to food crops and 92% to livestock husbandry. The households' income shared by agriculture (crop and livestock), forest and remittance was 37% and 20% respectively. Results further showed that income distribution was somehow equal with Gini coefficient 0.25 than with the 0.37 of landholdings size. But, average per capita income of households was lower than the national standard with 33% of households below the poverty thresholds and 0.0945 poverty gap index. Similarly, 85% respondents assured for the current degraded status of forest and 83% of households for not participated in forest management activities due to low awareness in 82% households. These findings shows the forest assets could be unduly degraded in the past and forest availability which is extracting from the remaining forest is also decreasing in the area. Thus, tendency of forest dependency has been shifting to the small scale farming, other livelihood sources such as local business and services. This information could be useful in planning and decision-making process in searching of better alternative for the local livelihood as well as sustainable forest conservation strategy.

• Applied Chemistry for Engineering
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• v.29 no.5
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• pp.510-518
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• 2018

Recently, lots of interests have been concentrated on the scrubber system that abates waste gases produced from semiconductor manufacturing processes. An effective design of the thermal decomposition reactor inside a scrubber system is significantly important since it is directly related to the removal performance of pollutants and overall stabilities. In the present study, a computational fluid dynamics (CFD) analysis was conducted to figure out the thermal and flow characteristics inside the reactor of wet scrubber. In order to verify the numerical method, the temperature at several monitoring points was compared to that of experimental results. Average error rates of 1.27~2.27% between both the results were achieved, and numerical results of the temperature distribution were in good agreement with the experimental data. By using the validated numerical method, the effect of the reactor geometry on the heat transfer rate was also taken into consideration. From the result, it was observed that the flow and temperature uniformity were significantly improved. Overall, our current study could provide useful information to identify the fluid behavior and thermal performance for various scrubber systems.

• Parasites, Hosts and Diseases
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• v.36 no.4
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• pp.227-234
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• 1998

Actin and tropomyosin of Cryptosporidium muris were localized by immunogold labeling. Two kinds of antibodies for actin labeling were used. The polyclonal antibody to skeletal muscle (chicken back muscle) actin was labeled on the pellicle and cytoplasmic vacuoles of parasites. The feeder organelle has showed a small amount of polyclonal actin antibody labeling as well. Whereas the monoclonal antibody to smooth muscle (chicken gizzard muscle) actin was chiefly labeled on the filamentous cytoplasm of parasites. The apical portion of host gastric epithelial cell cytoplasm was also labeled by smooth muscle actin together. The polyclonal antibody to tropomyosin was much more labeled at C. muris than host cells, so it could be easily identified even with low magnification (${\times}2,000$). The tropomyosin was observed along the pellicle, cytoplasmic vacuoles, and around the nucleus also. The skeletal muscle type actin seems to play a role in various celluar functions with tropomyosin in C. muris; on the other hand, the smooth muscle type actin was located mainly on the filamentous cytoplasm and supported the parasites firm attachment to host cells. Tropomyosin on the pellicle was thought to be able to stimulate the host as a major antigen through continuous shedding out by the escape of sporozoites or merozoites from their mother cells.

• Journal of the Korea Concrete Institute
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• v.22 no.5
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• pp.633-640
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• 2010

This study was performed to get basic information about properties of high blaine cement for shotcrete use. Particle size distribution, setting time and compressive strength test, analysis like as SEM, DSC thermal analysis, XRD was carried out to investigate principle properties of high blaine cement. Setting time of high blaine cement was shorter and compressive strength was higher than those of ordinary portland cement (OPC). Results of analysis showed early hydration products of high blaine cement is smaller and spread widely due to increased specific surface. From the SEM observation and analysis of DSC and XRD results, it was seen that the aluminates accelerators promoted calcium aluminium hydrates while the alkali free accelerators increased ettringite and monosulfates formation. Strength and setting time measurement of cement paste with aluminate accelerator is more effective than the alkali free accelerator in reducing the setting time and increasing early strength while alkali free accelerator is more effective in increasing the strength after 7 days.

• The Journal of the Korea Contents Association
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• v.20 no.2
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• pp.36-50
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• 2020

YouTube as a news channel is gaining popularity because it offers more interesting and in-depth news than traditional news media. However, YouTube has been criticized for its distribution of false information (or fake news) in Korea. Politicians are actively proposing a variety of bills to regulate YouTube's false information and a lot of studies proposed how to regulate YouTube's false information. This study looked at the users' experience and perception of false information and identified factors that affected the regulation of YouTube news. The results showed that the conservatives and the moderate groups were exposed to false information more than the progressives, and those in their 60s believed that false information was distributed on YouTube rather those in their 20s to 50s. The more people value freedom of expression, the more people trust TV Chosun news, the more people tend to oppose the regulation of information on YouTube. On the other hand, it turns out that the more people trust the news on both terrestrial broadcasting networks and JTBC, and the more people value the enlightening aspects on the news, the more they approve of Youtube regulation.

• Journal of Navigation and Port Research
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• v.38 no.6
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• pp.607-614
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• 2014

This article aims to explore and discuss research trends in global cruise industry using keyword network analysis. We visualize keyword networks in each of four groups of 1982-1999, 2000-2004, 2005-2009, 2010-2014 based on the top 20 keyword nodes' degree centrality and betweenness centrality which are selected among four centrality measurements, comparing them with frequency order. The article shows that keyword frequency collected from 240 articles published in international journals is subject to Zipf's law and nodes degree distribution also exhibits power law. We try to find out research trends in global cruise industry to change some important keywords diachronically, visualizing several networks focusing on the top two keywords, cruise and tourism, belonging to all the four year groups, with high degree and betweenness centrality values. Interestingly enough, a new node, China, connecting the top most keywords, appears in the most recent period of 2010-2014 when China has emerged as one of the rapid development countries in global cruise industry. Therefore keyword network analysis used in this article will be useful to understand research trends in global cruise industry because of increase and decrease of numbers of network types in different year groups and the visual connection between important nodes in giant components.

• Korean Chemical Engineering Research
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• v.51 no.6
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• pp.692-699
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• 2013

In this study, isothermal (350, 375, 400, 425, 450, 500, $850^{\circ}C$) experiments were carried out using a custom-made thermobalance to analyze the thermal decomposition properties of refuse plastic fuel (RPF), which is to be used as a cofiring fuel with a sub-bituminous coal at commercial circulating fluidized bed (CFB) boiler in Korea. In isothermal pyrolysis results, no change in the reaction model was observed in the temperature range of $375{\sim}450^{\circ}C$ and it was revealed that the first order chemical reaction (F1) is the most suitable among 12 reaction models. The activation energy shows similar results irrespective of application of reaction model in that the activation energy was 39.44 kcal/mol and 36.96 kcal/mol when using Arrhenius equation and iso-conversional method ($0.5{\leq}X{\leq}0.9$) respectively. Mean-while, the devolatilization time ($t_{dev}$) according to particle size (d) of RPF could be expressed as $t_{dev}=10.38d^{2.88}$ at $850^{\circ}C$, operation temperature of CFB and for even distribution and oxidation of RPF in CFB boiler, we found that the relationship of average dispersion distance (x) and particle size was $x{\leq}1.58d^{1.44}$.