• Resources Recycling
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• v.6 no.2
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• pp.22-28
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• 1997

In recent yean thc problem of wastc plastics arc greatly incrcascd with ihe result uf lndushial growth. As a rcsult the amount of wastc plaslics in domestic area is appraxhnately 2,300,000 t<~nin 1996 base and contmuously increasing more than 12% cvcry ycar. Thc disposal way of these waste plastics arc dlLl malnly rely~ng on landill1 or partially incinuralion So that it hss become a senous social problem due to the second envirnmentd pollution. The tcchnologics iar prducing oil from the waste plastics have hccn dcvelopcd far along pennd and currently some of them are in a commercialiration stage Pyrolysis process in one of the major process m heating waslc plaslics bul still has some restlichons for the cammcrc~dizatian duc lo 11s emnom~cal problems assaciated with a systcmiltlc lecd collcctionidispnsJ ways. Cansldenng cnvaomcnld problems, thc inclease m the charge for waste matcds trcatmcnt and thc lmlitarion ni disposal area, it is inteicstcd that the wastc plastics treabncnt by pyrolysn. which would be the safest and the most eilic~ent process for cnnvcrting fecd wastc to rc-usablc rcsourccs. would he predomhant m ihe near h~lurc Thc shldy aims inr the development of haslc ted~nolagy for scaling up to a com~nercial sire through pyrolys~s process which is cnnduclcd under the absence of air. Furthern~orc the waste plastics can be recycled as iual gas or oil wilhout harmful effects in enviroment, The waste w e d plastics arc pyrolyzed in (he fluidized bcd rcaclor under continuous way and thc ail ylcld gives approx~marcly 47 4%.

• The Korean Journal of Emergency Medical Services
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• v.1 no.1
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• pp.100-111
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• 1997

This is the first Korea study to evaluate the effects od the safety of ambulance driving and the occurrence of ambulance traffic accidents and to provide basic informaion for the description of various factors to reduce the ambulance traffic accidents. The major insturment of this study were Krean Self-Analysis Driver Opinionnaire. Questionnaire contains 8 items which measure driver's opinions or attitudes : driving courtesy, emotion, traffic law, speed, vehicle conditions, the use of drugs, high-risk behaviors, and human factors. To take the analysis of data, the total of 350 divers were investigated ambulance divers and others in Taejon City and others (6 City) from 1996. 1. July to 1996. 31. July. The data were analyzed by the descriptive statistics and the logistic regression - path analysis - with SPSS and SAS package program. The result are as follows : 1. There was desirable attitude group(16.2%) and undesirable attitude group(17.6%) on safety ambulance driving. 2. It have suggested that risk factors of ambulance traffic accidents much affected with emotion and speed control on safety ambulance driving < Y(Accdient) = -2.64 + 0.57 $X_1$ (Emotion Control) + 0.30 $X_2$(Seed control) + E > and motor traffic acident much affected with emotion control and high-risk behavior on safety driving < Y(Accident) = -1.11 + 0.33 $X_1$(Emotion Control) + 0.29 $X_2$(High-risk Behvior) + E > 4. The primary emphassis of ambulance drivers was make us realized that improthatnt factors on safety ambulance driving were 1)making way for emergent ambulance, 2)driver's career, 3)The ability of emergency medical technics, and the knowledge or under standing of ambulance way difficut(or easy) of accdess. 5. Almost 96.6% of respondents have agreed to necessity of emergency medical technics for ambulance drivers. 6. Almost 94.6% of respondents have consented to necessity of emergtency medical technicians for ambulance driving. 7. It have suggested that the proportion of traffic accident proportion by desitable attitude group(16.7%) was much less than that of undesirable attitude group(30.8%) on safety ambulance driving(P < 0.05)/Ps) Accidents are unplanned, unforesen incidents which can lead to harmful or unfortunate outcomes, Collisons are not accidents, since the basic cause of the majority of collisons invovles high-risk human behavior. Although there are many factors which contribute to accident causation, four basic factors seem to predominate in most traffic related situations. These four factors include: the human factor, the vehicle factor, the environmental factors and destination factor(Peto G. et al. 1995).

• Journal of Science and Technology Studies
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• v.19 no.3
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• pp.119-166
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• 2019

The risk of electromagnetic field(EMF) from power lines has been heavily disputed whenever high-voltage power line towers were built in South Korea. Local communities and civic groups had regarded burying the lines in the ground as an alternative to building power line towers. In 2014, however, when an elementary school science teacher reported the results of EMF measurements over the underground power lines to the Asian Citizens' Center for Environment and Health (ACCEH), the risk controversy over underground power lines took a whole new turn. The level of EMF from underground power lines turned out to be higher, and therefore more harmful than that from power line towers. In the debates that took place from then on over the EMF risk, ACCEH and NIER(National Institute of Environmental Research) presented conflicting topographies of EMF risk. This paper examines measuring practices of ACCEH and NIER by analyzing the measuring sites, measuring devices, and measuring heights chosen by each organization. This paper further examines how ACCEH and NIER mobilized various standards(EMF exposure limit, measurement guideline, categorization of carcinogens) differently. This controversy on the EMF from underground power lines of Seoul has raised concerns on the non-thermal effects of EMF in the long-term exposure and has led people to question whether burying the power lines is the safe alternative to building power line towers. Furthermore, this suggests conflicting answers on whether Seoul, where 90 % of transmission lines were already buried, is a safely managed place or not.

• Journal of agriculture & life science
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• v.45 no.6
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• pp.115-124
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• 2011

This study was conducted to find a useful alternative herbivore system with which to study the effects of ultraviolet exposure on the pathogenicity and survival of Korean isolated entomopathogenic nematodes (Heterorhabditis sp. 202 strain, Heterorhabditis sp. Gyeongsan strain, Steinernema sp. 223 strain, S. carpocapsae Pocheon strain, S. glaseri Dongrae strain and S. longicaudum Nonsan strain). Pathogenicity of entomopathogenic nematodes against silkworm, Bombyx mori, differed depending on the nematode species and strain and instar of silkworm challenged. Steinernematidae were relatively more pathogenic to the 5th instar silkworms, whereas Heterorhabditidae were more pathogenic to the 1st instars. UV-C exposure was harmful to entomopathogenic nematodes. All nematodes were killed within 60 minutes of exposure of UV-C, and after 10 min of exposure they caused only 6.7% corrected mortality of silkworms. Silkworms were not infected when they were fed S. carpocapsae Pocheon strain treated mulberry leaves which were exposed to UV intensity of about $2.3mW/cm^2$ for 4 hours in the field. Pathogenicity of S. carpocapsae was not significantly reduced after 1 hour of exposure to $4.0mW/cm^2$ UV intensity on the mulberry leaves against silkworms.

• Korean Journal of Social Welfare Studies
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• v.43 no.1
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• pp.389-411
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• 2012

A new era of research has focused on examining the growth of change in drinking problems among the elderly. Thus, the purpose of the present study was two fold: (1) to investigate trajectories of drinking problems(CAGE) among the Korean elderly(age$${\geq_-}65$$); and (2) to identify the predicting factors for the intercept and the slope of alcohol problems using multi-level growth curve model. Data come from three waves(1st wave(2006)~3rd wave(2008) of the Korea Welfare Panel(KWP) study. The results indicated that the levels of drinking problems decreased over time and that age, gender, marital status, religion, poverty, self-rated health, and social relationship satisfaction were associated with the baseline CAGE. Further analysis showed that social relationship satisfaction affected the declining slope of drinking problems over time. Specifically, among those who satisfied social relationship, there was a sharp decline of CAGE over time. Overall findings highlight the importance of developing and implementing effective alcohol prevention programs for the elderly in the community settings to mitigate the harmful effects of various psycho-social stressors. Especially, programs to maintain and form healthy social support network are suggested as critical interventions for prevention as well as recovery of alcohol problems in late life.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.9 no.6
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• pp.711-718
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• 2019

Spectrum analyzer and electromagnetic field meter were used to investigate the EM generation behaviour in different types of home electrical appliances. During microwave oven operation, the EM power measured at a point 30cm apart was measured in the range of 8~11mW/㎡, the strength of the low frequency magnetic field was 60~80mG and the electric field strength was measured at 150~160V/m. For smart phone wireless charging pad, it was measured at an electromagnetic power of 0.4mW/㎡, an electric field of 160 V/m and a magnetic field of 1mG at a point 10cm away. For microwave oven and wireless charging pad, if used within 10cm, the size of the electric field has been measured at a large value that exceeds the human body protection standard and may be hazardous to humans. On the other hand, home appliances such as TVs, hairdryers and refrigerators all showed very low levels of electromagnetic waves, electric fields and magnetic fields, with no harmful effects seen. For electromagnetic shielding, the metal Cu fabric and metal foil had a high level of EM shielding, while polymer films had a low EM shielding characteristic.

• Membrane Journal
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• v.31 no.2
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• pp.101-119
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• 2021

The demand for clean water is virtually present in all modern human societies even as our society has developed increasingly more advanced and sophisticated technologies to improve human life. However, as global climate change begins to show more dramatic effects in many regions in the world, the demand for a cheap, effective way to treat wastewater or to remove harmful bacteria, microbes, viruses, and other solvents detrimental to human health has continued to remain present and remains as important as ever. Well-established synthetic membranes composed of polyaniline (PANI), polyvinylidene fluoride (PVDF), and others have been extensively studied to gather information regarding the characteristics and performance of the membrane, but recent studies have shown that making these synthetic membranes conductive to electrical current by doping the membrane with another material or incorporating conductive materials onto the surface of the membrane, such as allotropes of carbon, have shown to increase the performance of these membranes by allowing the adjustability of pore size, improving antifouling and making the antibacterial property better. In this review, modern electrically conductive membranes are compared to conventional membranes and their performance improvements under electric fields are discussed, as well as their potential in water filtration and wastewater treatment applications.

• Korean Journal of Organic Agriculture
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• v.28 no.4
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• pp.591-604
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• 2020

The objectives of this study were to find out the best condition of extracting methods of limonene from citron and to determine effects of limonene on immune modulation activity by measuring cytokine secretion using RAW 264.7 mouse macrophage cells. When distilled water was used as a solvent instead of organic solvents to extract limonene from citron, addition of refluxing process to simultaneous steam distillation extraction method was found to be much effective in extracting limonene. However, it required longer extraction time than using other organic solvents. Limonene extracts showed increased IL-β and IL-6 but decreased the TNF-α gene expression in limonene concentration dependant manner. However oral administration of limonene extracts to mice did not influence significantly compared to control in in vivo experiment. It might be due to that the mice were kept in well controlled and complete environment. Limonene, a natural material from citron has been approved to have a immune-modulation activity in the present study and have a potential as a feed additive that is environmentally friendly and no harmful. Further study with protected limonene, for example, for the protection of limonene from oxidation or bypass the ruminal degradation in order consequently to increase immune-modulation activity might be useful as a further research.

• Cross-Cultural Studies
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• v.46
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• pp.1-20
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• 2017

This study tries to examine the emotion of the elite characters in Son Jangsoon's early novel, The Koreans. In this novel, most characters are found to have an envy feeling, except for two female characters, Heeyeon and Sue Han. Although the writer does not consciously explore the envy feeling here, she excellently represents the harmful effects of the envy feeling. In this novel, the envy feeling is related to the desire for success and its frustration. In 1960's, people had high expectation of improvement in their individual lives. The elite groups were more likely to have a successful life with good education. But in this novel, these elite people suffer from frustration of their desire and experience of the envy feeling. The impressive point in this novel is that not only females but also males are shown to have the envy feeling. Envious people have the tendency to compare themselves with people around them, to feel shame in an inferior position and to aspire for superiority. In these envious characters, the feeling of envy reveals their lack, their inferiority and it never provides them with the way to escape from their suffering situation. The writer suggests that the envy feeling can be overcome by pursuing other valuable things and focussing not on other people's desire but on their own desire.

• Korean Journal of Clinical Laboratory Science
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• v.50 no.4
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• pp.391-398
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• 2018

Mesenchymal stem cells (MSCs) are an attractive resource for refractory patients because of their anti-inflammatory/immunomodulatory capability and multi-lineage differentiation potential. The transplantation of MSCs has led to positive results in preclinical and clinical application to various diseases, including autoimmune disease, cardiovascular disease, cancer, liver cirrhosis, and ischemic stroke. On the other hand, studies have shown that paracrine factors, not direct cell replacement for damaged cells or tissue, are the main contributors in MSC-based therapy. More recently, evidence has indicated that MSC-derived exosomes play crucial roles in regulating the paracrine factors that can mediate tissue regeneration via transferring nucleic acids, proteins, and lipids to the local microenvironment and cell-to-cell communication. The use of these exosomes is likely to be beneficial for the therapeutic application of MSCs because their use can avoid harmful effects, such as tumor formation involved in cell transplantation. Therefore, therapeutic applications using MSC-derived exosomes might be safe and efficient strategies for regenerative medicine and tissue engineering. This review summarizes the recent advances and provides a comprehensive understanding of the role of MSC-derived exosomes as a therapeutic agent.