• Journal of Korean Society of Environmental Engineers
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• v.39 no.7
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• pp.391-402
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• 2017

Particulate matter becomes an important issue in the environmental society recently so that it is necessary to evaluate that the commercial application of baghouse systems for effective control of fine particulates is viable. A laboratory-scale baghouse experimental apparatus with filter bags made of PTFE felt or PTFE felt coated with PTFE membrane is used to investigate the filtration performances of fine particulates. Experiments by changing filtration velocity, inlet dust concentration, and average dust particle size show that the dust collection efficiency becomes higher at lower filtration velocity, higher inlet dust concentration and larger average dust particle size. The total pressure drop through the filter media and dust layer becomes higher at higher filtration velocity and higher inlet dust concentration. The dust collection efficiency is higher and the pressure drop is lower at a baghouse with filter bags coated with PTFE membrane than that without membrane coating. From the result that the dust collection efficiency of $PM_{2.5}$ in a reasonable filtration velocity range during off-line pulsing at a baghouse with PTFE felt bag filters coated with PTFE membrane is as high as 99.99%, it is confirmed that the use of baghouse is an effective measure to control the fine particulates.

• Applied Biological Chemistry
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• v.20 no.2
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• pp.228-235
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• 1977

The yeast strain was isolated from food industry waste water and its identification and biological characteristics were investigated. The optimum condition for cultivations and its activities for the reduction of B.O.D. on the food industry waste water were also confirmed. The results are as follows; 1) The isolated was identified as Candida curvata. 2) Candida curvata grew well in all of the experimented media, so and it can be regarded as a useful strain in the treatment of food industry waste water. 3) There was only a slight difference in the induction period between sterilized cultivation and unsterilized cultivation. But in the ice cream waste water, the period was considerably longer in unsterilized cultivation. 4) Specific rate of growth of Candida curvata in sugar waste water was 0.50/hr, ice cream waste water 0.50/hr, and beer waste water 1.0/hr. 5) Increasing of innoculum reduced the induction period in unsterilized cultivation. 6) The amount of dried yeast from sugar waste water were $175mg/{\ell}$, ice cream waste water $628mg/{\ell}$, and beer waste water $857mg/{\ell}$. Crude protein content in the dried yeast from sugar waste water were 52%, ice cream waste water 54%, and beer waste water 54%. 7) The rate of BOD reduction in sugar waste water were 49%, ice cream waste water 80%, and beer waste water 64%.

• Journal of Broadcast Engineering
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• v.14 no.2
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• pp.134-143
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• 2009

In this paper, we propose a new relay selection algorithm for a two-way multiple relay channel. In the two-way multiple relay channel, two users exchange information with each other via multiple relays. The relays use a decode-and-forward or amplify-and-forward protocol, and exploit the combining process of the received packets to reduce the required channel resources. In the multiple relay network, diversity gain is achieved as the number of relays increases, and various schemes are proposed. In this paper, we propose a single best relay selection scheme based on instantaneous channel conditions. First of all, relays obtain the instantaneous channel state information in the handshaking process, and a single best relay is selected in a distributed methods prior to data transmissions. The relay selection metric is proposed so that the end-to-end channel condition is evaluated based on the intantaneous channel state informations. Simulation results show that the proposed relay selection algorithm achieve the increased throughput and diversity order when the number of potential relays is increased.

• Journal of Distribution Science
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• v.13 no.2
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• pp.75-83
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• 2015

Purpose - This study aims to identify the effects of communication cues, anonymity, and social presence on group polarization in computer-mediated communication (CMC) settings. Extant literature has introduced some theoretical backgrounds of social presence and SIDE (Social Identity model of Deindividuation Effects) to explain the effects of communication cues and anonymity. The concept of social presence emphasized the mediating role on communication cues and anonymity. However, most literature did not measure social presence and compare group polarization of all condition groups. This does not sufficiently explain the result of group polarization. Research design, data, and methodology - We believe that the direct impact of anonymity on group polarization can provide a more admissible and clearer explanation for the results. In addition, this study categorizes anonymity into two levels, as anonymity of group and anonymity of self. To justify the anonymity view, a laboratory experiment was conducted. The experiment was conducted in communication cues settings (visual cue; without visual cue) and anonymity settings (identified; anonymous). Each of the four settings has 10 groups consisting of five subjects each (total 200 subjects). The subjects are undergraduates from a large university, majoring in business. All experimental procedures and calculations of choice shift and preference change follow the literature. Results - First, the removal of visual cues does not produce a significant impact on group polarization, which cannot be explained by the social presence view. Second, the anonymous condition does not significantly affect group polarization, which also cannot be explained by the social presence view. However, the anonymous condition directly affects group polarization. Specifically, anonymity of self has a stronger effect on group polarization than anonymity of group. The result explains about the leading factor affecting group polarization. This study examines another view of how computer-mediated communication may be associated with group polarization. The process and outcome data from the experiment reveal that group polarization is not affected by level of social presence, but by level of anonymity. Group discussions conducted with visual cue CMC setting and identified CMC setting result in weaker group polarization. Conversely, group discussions conducted without visual cue CMC setting and anonymous CMC setting lead to stronger group polarization. The results of the study have the following implications. First, they provide clues for business organizations to design the most appropriate media conditions and preemptive social conditions to implement when making group decisions through CMC, to maximize achievements, generate amicable agreements, or actively share information. Second, this study can be useful in analyzing different adverse effects generated through Internet use. Conclusions - This research can help explain discussions and decision-making actions on Internet forums, which have recently increased, as well as providing a foundational basis in newly establishing policies for the forums. Finally, it should be noted that many other factors such as group size, topics, and group history may affect group polarization. These should be examined in future studies.

• The Journal of the Korea Contents Association
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• v.20 no.5
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• pp.457-466
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• 2020

The purpose of this study is to find out what the main agenda of social formation is and how it changes through the media by utilizing the news big data of COVID-19 which is spreading recently, and to suggest the direction of future reporting. In order to achieve the purpose of the research, 47,816 cases of news big data reported from December 31, 2019 to March 11, 2020 were divided into four periods based on the fourth stage of the crisis warning for infectious diseases, and a total of 20 topics were derived. Based on the results of the Topic Modeling analysis, this study proposed the following. First, it is necessary to refrain from provocative expressions such as "anxiety" and "fear" and use neutral and objective reporting terms. Second, more in-depth and contextual news production is required, breaking away from simple event news production. Third, it is necessary to prepare detailed crisis communication manuals for each situation related to infectious diseases. Fourth, we need reports that focus on citizens-led efforts to overcome the crisis. This research has the academic significance that it is the first paper to analyze news big data on COVID-19 using the Topic Modeling Analysis method, and the policy significance that can be used as the basis for developing national crisis communication policy.

• Nutrition Research and Practice
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• v.1 no.1
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• pp.29-35
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• 2007

Trace mineral studies involving metal ion chelators have been conducted in investigating the response of gene and protein expressions of certain cell lines but a few had really focused on how these metal ion chelators could affect the availability of important trace minerals such as Zn, Mn, Fe and Cu. The aim of the present study was to investigate the availability of Zn for the treatment of MC3T3-E1 osteoblast-like cells and the availability of some trace minerals in the cell culture media components after using chelexing resin in the FBS and the addition of N,N,N',N'-tetrakis-(2-pyridylmethyl)ethylenediamine (TPEN, membrane-permeable chelator) and diethylenetriaminepentaacetic acid (DTPA, membrane-impermeable chelator) in the treatment medium. Components for the preparation of cell culture medium and Zn-treated medium have been tested for Zn, Mn, Fe and Cu contents by atomic absorption spectrophotometer or inductively coupled plasma spectrophotometer. Also, the expression of bone-related genes (ALP, Runx2, PTH-R, ProCOL I, OPN and OC) was measured on the cellular Zn depletion such as chelexing or TPEN treatment. Results have shown that using the chelexing resin in FBS would significantly decrease the available Zn (p<0.05) $(39.4{\pm}1.5{\mu}M\;vs\;0.61{\pm}10.15{\mu}M)$ and Mn (p<0.05) $(0.74{\pm}0.01{\mu}M\;vs\;0.12{\pm}0.04{\mu}M)$. However, levels of Fe and Cu in FBS were not changed by chelexing FBS. The use of TPEN and DTPA as Zn-chelators did not show significant difference on the final concentration of Zn in the treatment medium (0, 3, 6, 9, $12{\mu}M$) except for in the addition of higher $15{\mu}M\;ZnCl_2$ which showed a significant increase of Zn level in DTPA-chelated treatment medium. Results have shown that both chelators gave the same pattern for the expression of the five bone-related genes between Zn and Zn+, and TPEN-treated experiments, compared to chelex-treated experiment, showed lower bone-related gene expression, which may imply that TPEN would be a stronger chelator than chelex resin. This study showed that TPEN would be a stronger chelator compared to DTPA or chelex resin and TPEN and chelex resin exerted cellular zinc depletion to be enough for cell study for Zn depletion.

• Women's Health Nursing
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• v.6 no.4
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• pp.549-565
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• 2000

Comprehensive review of the literature was conducted to determine 1) selected risk factors and its impact that affect pregnancy outcome such as smoking, alcohol consumption, and substance abuse 2) these factors can facilitate future strategies for health promotion and prevention for both pregnant women and fetus. Review of literature were extracted from searching MEDLINE(1966 - Oct. 2000). CINAHL (1982 - Oct. 2000) and the domestic literature. The following factors were identified: 1. The effects of risk behaviors on pregnancy. ${\cdot}$Maternal smoking was associated with the occurrence of premature or LBW delivery, fetal growth retardation, extremities defects, heart defects and sudden infant death syndrome. ${\cdot}$Maternal alcohol consumption was associated with spontaneous abortion, premature or LBW delivery, morphologic/neurologic problems, especially fetal alcohol syndrome. ${\cdot}$Heroin was associated with withdrawal after birth in which were born to heroine addicts for gestational age and lung maturation in animal studies. ${\cdot}$Cocaine was associated with spontaneous abortion, abruptio placenta and a poor response to environmental stimuli. ${\cdot}$So far, the effects of caffeine on pregnancy was controversial, but severe caffeine consumption was associated with premature or LBW delivery, spontaneous abortion, still birth and dystocia. 2. Intervention methods and its effects identified were as follows ${\cdot}$Conducted intervention for smoking, alcohol and drug consumption were single or combined. ${\cdot}$Intervention methods were counseling, phone contact, mailing, use of educational videotape, booklet, support person and alternatives such as nicotine patch. ${\cdot}$The interventions increased the rates of smoking cessation during pregnancy and awareness of the risk of drug consumption, and decreased amount of alcohol consumption. ${\cdot}$The intervention outcome found positive effect on birth weight and length. 3. Our recommendations were as follows ${\cdot}$The personal and social cognition should be enhanced through education and the mass media. ${\cdot}$It's necessary to educate and give information of preconceptional care, planned pregnancy and early prenatal care for optimal pregnancy outcome. ${\cdot}$It's necessary to develop comprehensive assessment tool which is reliable and valid on smoking, alcohol consumption and substance abuse to identify supportive or interventional program.

• Cartoon and Animation Studies
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• s.40
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• pp.177-209
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• 2015

The purpose of this study is to determine the meaning and function of black and white in the comic strip, which are mounted on the book pages. The role of space in comic strip, compared to the role of time in the cinema, enable to feel the role of the time in the book. Therefore storytelling of comic strip has been placed in the inseparable relationship with space. My aim is to think about the black and white meaning in the visual media, especially the use of black and white which is highlighted in the comic strip. Black and white doesn't mean a loss of color in the comic strip but it works around 2 important notions : readability, modernity (with minimalism). In comic strip, 'black and white' is not a true colour but it is complex items which indicate symbolic significances. Moreover it is also a notion which enhance 'existence and absence' and 'visible and invisible'. That's why to analyze and to understand how the space is organized in comic strip page, i chose several examples extract from black and white comic strip.

• The Journal of the Korea Contents Association
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• v.14 no.6
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• pp.34-43
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• 2014

Young Chinese audience can select and watch TV dramas, movies and entertainment programs from many different nations, such as Korea, America, Japan, England, Thailand, India, and so on, through multiple channels, such as online video sites - iQiyi, Youku, LeTV, PPTV, and many others - which were induced by changes in media environment. Various genres of Korean popular culture have recently become popular in China, but this phenomenon differs from the early Korean Wave. During the earlier period (from 1997 to the early 2000s) of the Korean Wave, soap operas were popular among middle-aged women, but now various other genres, such as K-pop, entertainment programs, etc., are also popular in China. The purpose of this study is to explore how young Chinese audiences use foreign pop culture, including their preferred genres, reasons for preferring these genres, and the relationship between the preferred pop culture and national image in Korean, American, and Japanese pop culture were analyzed. According to the study results, similarities and differences between preferred genres and the reasons for preferring these genres, and also a close correlation between preferred pop culture and national image were found. These findings will be fundamental for supporting the continual development of the Korean Wave in China.

• The Journal of the Korea Contents Association
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• v.20 no.7
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• pp.66-85
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• 2020

The purpose of this study is to explain and predict trends the AI development process based on AI technology patents (total) and AI reporting frames in major newspapers. To that end, a summary of South Korean and U.S. technology patents filed over the past nine years and the AI (Artificial Intelligence) news text of major domestic newspapers were analyzed. In this study, Topic Modeling and Time Series Return Analysis using Big Data were used, and additional network agenda correlation and regression analysis techniques were used. First, the results of this study were confirmed in the order of artificial intelligence and algorithm 5G (hot AI technology) in the AI technical patent summary, and in the news report, AI industrial application and data analysis market application were confirmed in the order, indicating the trend of reporting on AI's social culture. Second, as a result of the time series regression analysis, the social and cultural use of AI and the start of industrial application were derived from the rising trend topics. The downward trend was centered on system and hardware technology. Third, QAP analysis using correlation and regression relationship showed a high correlation between AI technology patents and news reporting frames. Through this, AI technology patents and news reporting frames have tended to be socially constructed by the determinants of media discourse in AI development.