• Resources Recycling
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• v.29 no.5
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• pp.15-27
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• 2020

Microplastics are recognized as critical and serious environmental problem in worldwide. Plastics are inexpensive, lightweight, excellent in processability, and various in material-specific properties. Along industrial development, the production and disposal amount of plastics are also rapidly increasing. In particular, abundant plastic wastes are eventually disposed into marine environment with harmful impacts on the ecosystem. Therefore, lots of relevant studies were recently progressed in various fields. However, many studies are being just conducted due to its difficulty in applying a general treatment method for those small particle sizes and their various characteristics. In the meantime, lots of researches are being conducted on applying methods using physical properties such as specific gravity, magnetic, and electrostatic separation, which are beneficiation processes of minerals. However, since it is still in the laboratory stage, the development of larger scale separation technology for efficient treatment is urgent.

• Korean Journal of Construction Engineering and Management
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• v.19 no.5
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• pp.90-100
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• 2018

Government needs a risk assessment method that is effective in preventing accidents as a part of the three principal projects of the government for protecting the people's lives for establishing preventative measures to prevent accidents in the construction sites, which accounted for more than half of all accidental mortality accidents, and promote the safety-oriented culture for making fundamental changes. Accidents at the medium and small sized construction sites accounted for 88.9% of the total construction accidents. The data indicates that improper management and lack of advanced safety measures due to the absence of a safety supervisor are the biggest problems. It is believed that active measures to evaluate and prevent risks at construction sites are necessary for preventing accidents in the medium and small sized construction sites. The objectives of this study is to identify the key risk items of common accident causes and propose a practical, preemptive, and improved risk assessment method by evaluating the problems in the safety management of construction sites for reducing the accident rate in the medium and small sized construction sites.

• Korean Journal of Construction Engineering and Management
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• v.21 no.4
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• pp.38-49
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• 2020

As the quality of life has been improving, people are getting higher interest and higher expectation for safety. However, the accident rate at the construction site is still high. Therefore, it is urgent to secure the safety at the construction work. Due to the nature of the construction industry, construction sites are directly exposed to the external environment. The possibility of accident occurrence is increased due to various factors such as the always variable processes, the diversity of manpower input, the increase in vulnerable class, and the danger of construction equipment..Particularly, the disasters occurring at the small- or medium-sized construction sites (budget ≤ 12 billion KRW) account for 88.9% of the total disasters at construction sites (73.4% for casualty). It was due to the lack of management caused by the absence of supervisors and insufficient safety measures. Moreover, it is difficult for the small- or medium-sized construction sites to apply basic safety measures such as safety education and safety facility installation by themselves in order to prevent disasters because they don't have sufficient safety organizations. It is because they have relatively less safety personnel and poorer technology system than large-sized construction sites. Therefore, in order to reduce accidents in construction, it is necessary to prevent accidents at the small- and medium-sized construction sites. From this point of view, the objectives of this study were to identify the key risk items causing accidents frequently by analyzing the accidents at construction sites and identifying problems associated with safety management, and to secure the safety at the small- and medium-sized construction sites.

• Journal of Science and Technology Studies
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• v.4 no.2 s.8
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• pp.33-66
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• 2004

In these days, science is too complex and comprehensive scientific practices to be reduced to scientific knowledge. Also it's actors go beyond the limit of scientist society to the broad range of supporting system scientific journalism, education, and business. Science is very important cultural practice of our times. This Study focus on the effect of interdisciplinary approach in understanding modern science culture. First, this paper suggest the approach of public understanding of science(PUS) as a framework PUS has provided new perspectives for the relation of scientific knowledge and understanding. Traditional approach(so-called 'deficit model') regarded understanding as mere transportation of scientific knowledge. So it may be called 'knowledge-oriented approach' to understanding. But PUS consider understanding process of 'dynamic reconstructing' which is occurred in complex socio-cultural context. Second, this article analysis the Korea University STS course(2002-2003) 'Science Technology & Society' as the case study. The case study examine how interdisciplinary approach help students to understand 'sciene in the making'.

• Journal of dental hygiene science
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• v.9 no.2
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• pp.203-210
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• 2009

The following are the results of questionnaire research targeting 213 people at 4 dental clinics in Geoje region in order to examine recognition on the periodontal health in Inpatients of dental clinic. 1. In the item of recognition on periodontal health, the patients, who know about whether or not recognizing periodontal disease, were indicated to be 62.9%. Women were knowing better than men. The significant difference by gender was indicated(p < .01). As for a route of acquiring information on periodontal disease, a case of obtaining via television and internet was surveyed to be 31.6%. As for recognition on frequency of tooth scaling, a case of recognition as saying of the necessity of doing once a year was indicated to be 43.7%. The significant difference was indicated depending on job and academic background(p < .001). 2. As for the periodontal-health status, the patients of recognizing that the condition in the gums is mostly healthy were indicated to be 75.1%. The more professional job led to showing the significant difference depending on occupation(p < .001). As for a reason for a visit to dentistry, a case of visiting due to smell in the mouth was indicated to be 18.1%. As for kinds of dental treatment, the patients. who received the tooth scaling by visiting a dental clinic. were the largest with 46.5%. The significant difference was indicated depending on job(p < .01), academic background(p < .05), And monthly income(p < .001).

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.11
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• pp.1966-1975
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• 2008

NEMO Basic Support Protocol standardized in IETF provides the seamless communication environment to all nodes within the mobile network regardless of the network movement while the network is moving. According to the standard, when the mobile network moves outside of its home network the network can make use of the binding update message or dynamic routing protocol in order to register the mobility information into the Home Agent(HA). But because these two methods don't consider the route optimization, all packets destined to Mobile Network Nodes(MNNs) attached into the Mobile Router(MR) have to go through HAs of MRs so that they bring on the transmission delay and the waste of the bandwidth. This situation is to be worse and causes the packet fragmentation problem if MRs within the mobile network are nested. Even though there have been some researches about the route optimization to recover the problems, they have problems in the packet transmission performance side. In this paper, we propose a new scheme to improve the network performance by using a dynamic routing protocol and minimizing the number of HAs on the end-to-end path. Various performance evaluations show that the proposed mechanism gives better performance in view of the packet transmission compared to the existing schemes.

• (The)Study of the Eastern Classic
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• no.41
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• pp.187-209
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• 2010

This thesis to be studied conversation by writing between the medical staff of Chosun(朝鮮) and Japan in 1763. Both countries the medical staff and intellectuals meet that communication, confrontation and conflict, exchanges and cooperation in 18C. They met greeting and sing in chorus. Chosun keep checking in western medicine of Japan. They are compared to customs of two countries. Also Japanese increase interest in the Hangeul(한글). Confrontation and conflict resulted from history recognition and difference of viewpoint of two countries. Especially Kokugaku(古學) have many influence on this situation. So battle come and go to study of Ogyu Sorai(荻生?徠) and Dajai Jun(太宰純). But this situation includes Mutual misunderstanding. Because of limitation on conversation by writing. Exchanges and cooperation take shape on the medical staff that a process of ginseng(人蔘), medical treatment. And two countries promote goodwill that method of buying books in Japan and medical treatment. In conclusion, intellectuals of Chosun and Japan have some misunderstanding and distrust. but they are communication with Chinese writing that east asian's common language. Also exchange its views and information.

• (The)Study of the Eastern Classic
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• no.69
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• pp.419-450
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• 2017

This study aims to discover the clue of the current modern postal system development by looking at the delivery patterns of Korean letters during the Joseon Dynasty. A letter is a text medium that the sender sends to a recipient by sending a message of news. The form and contents of the letter are influenced by the various surrounding factors and are adapted to circumstances. The study aims to clear up the method of delivery and the nature of the transmitter among the environmental factors which affects the format and contents of Korean letters. Depending on the public or private matters, the delivery method is divided into a public agency and a private messenger, or divided into one-phase delivery and the multi-phase delivery depending on whether or not a phase is divided into stages. It is also divided into a one-way and a round-transmission depending on whether or not it is round-switched. The transmitter is divided into a verbal communication, the letter and verbal communication, and the letter communication according to whether or not it is by verbal, and divided into the relational and the non-relational person according to the relationship with the sender. Also depending on whether the transmitter is exclusive or not, it is divided into the exclusive messenger and the messenger who deliver a letter incidentally while come and go. In the aspect of the delivery method, We can see the possibility of developing to a modern mail system through the public method, the multi-phase delivery, one-way delivery and in the aspect of the transmitter, we can see the possibility through the letter delivery, non-related transmitter, and the exclusive messenger.

• Journal of Korean Medical Science
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• v.33 no.52
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• pp.336.1-336.12
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• 2018

Background: We aimed to investigate mucosal immunity related to forkhead box P3 ($FOXP3^+$) regulatory T (Treg) cells, T helper 17 (Th17) cells and cytokines in pediatric inflammatory bowel disease (IBD). Methods: Mucosal tissues from terminal ileum and colon and serum samples were collected from twelve children with IBD and seven control children. Immunohistochemical staining was done using anti-human FOXP3 and anti-$ROR{\gamma}t$ antibodies. Serum levels of cytokines were analyzed using a multiplex assay covering interleukin $(IL)-1{\beta}$, IL-4, IL-6, IL-10, IL-17A/F, IL-21, IL-22, IL-23, IL-25, IL-31, IL-33, interferon $(IFN)-{\gamma}$, soluble CD40L, and tumor necrosis factor-${\alpha}$. Results: $FOXP3^+$ Treg cells in the lamina propria (LP) of terminal ileum of patients with Crohn's disease were significantly (P < 0.05) higher than those in the healthy controls. $ROR{\gamma}t^+$ T cells of terminal ileum tended to be higher in Crohn's disease than those in the control. In the multiplex assay, serum concentrations (pg/mL) of IL-4 ($9.6{\pm}1.5$ vs. $12.7{\pm}3.0$), IL-21 ($14.9{\pm}1.5$ vs. $26.4{\pm}9.1$), IL-33 ($14.3{\pm}0.9$ vs. $19.1{\pm}5.3$), and $IFN-{\gamma}$ ($15.2{\pm}5.9$ vs. $50.2{\pm}42.4$) were significantly lower in Crohn's disease than those in the control group. However, serum concentration of IL-6 ($119.1{\pm}79.6$ vs. $52.9{\pm}39.1$) was higher in Crohn's disease than that in the control. Serum concentrations of IL-17A ($64.2{\pm}17.2$ vs. $28.3{\pm}10.0$) and IL-22 ($37.5{\pm}8.8$ vs. $27.2{\pm}3.7$) were significantly higher in ulcerative colitis than those in Crohn's disease. Conclusion: Mucosal immunity analysis showed increased $FOXP3^+$ T reg cells in the LP with Crohn's disease while Th17 cell polarizing and signature cytokines were decreased in the serum samples of Crohn's disease but increased in ulcerative colitis.

• Journal of Biomedical and Translational Research
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• v.19 no.4
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• pp.116-124
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• 2018

Korean Native Pig (KNP) has a uniform black coat color, excellent meat quality, white colored fat, solid fat structure and good marbling. However, its growth performance is low, while the western origin Yorkshire pig has high growth performance. To take advantage of the unique performance of the two pig breeds, we raised crossbreeds (KNP ${\times}$ Yorkshire to make use of the heterotic effect. We then analyzed the liver transcriptome as it plays an important role in fat metabolism. We sampled at two stages: 10 weeks and at 26 weeks. The stages were chosen to correspond to the change in feeding system. A total of 16 pigs (8 from each stage) were sampled and RNA sequencing was performed. The reads were mapped to the reference genome and differential expression analysis was performed with edgeR package. A total of 324 genes were found to be significantly differentially expressed (${\left|log2FC\right|}$ > 1 & q < 0.01), out of which 180 genes were up-regulated and 144 genes were down-regulated. Principal Component Analysis (PCA) showed that the samples clustered according to stages. Functional annotation of significant DEGs (differentially expressed genes) showed that GO terms such as DNA replication, cell division, protein phosphorylation, regulation of signal transduction by p53 class mediator, ribosome, focal adhesion, DNA helicase activity, protein kinase activity etc. were enriched. KEGG pathway analysis showed that the DEGs functioned in cell cycle, Ras signaling pathway, p53 signaling pathway, MAPK signaling pathway etc. Twenty-nine transcripts were also part of the DEGs, these were predominantly Cys2His2-like fold group (C2H2) family of zinc fingers. A protein-protein interaction (PPI) network analysis showed that there were three highly interconnected clusters, suggesting an enrichment of genes with similar biological function. This study presents the first report of liver tissue specific gene regulation in a cross-bred Korean pig.