• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.1
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• pp.47-52
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• 2008

As the packing density of IC devices gets ever higher, the thickness of the gate $SiO_2$ layer of the MOS devices is now required to be reduced down to 1 nm. For such a thin $SiO_2$ layer, the MOS device cannot operate properly because of tunneling current and threshold voltage shift. Hence there has been much effort to develop new dielectric materials which have higher dielectric constants than $SiO_2$ and is free from such undesirable effects. In this work, the physical and electrical characteristics of ALD $ZrO_2$ film have been studied. After deposition of a thin ALD $ZrO_2$ film, it went through thermal treatment in the presence of argon gas at $800^{\circ}C$ for 1 hr. The characteristics of morphology, crystallization kinetics, and interfacial layer of $Pt/ZrO_2/Si$ samples have been investigated by using the analyzing instruments like XRD, TEM and C-V plots. It has been found that the characteristics of the $Pt/ZrO_2/Si$ device was enhanced by the thermal treatment.

• Journal of environmental and Sanitary engineering
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• v.22 no.3
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• pp.13-26
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• 2007

Changes in the characteristics of dissolved organic matter was studied at selected stations in the Nakdong river basin using physical and chemical methods. Characteristics of dissolved organic matters were analysed and assessed. Production of disinfection byproducts were also investigated. 1. Result of relatedness study among each items of analyses showed that relatedness on BOD values were highest with cattle excrement treatment facilities where there is no synthetic organic materials and relatedness on $COD_{Mn}$ were highest at the mainstream Nakdong river. In case of $COD_{Cr}$ (which has more oxidative power than $COD_{Mn}$), the values were higher in the sidestreams indicating the higher content of recalcitrant compounds. The relatedness values for the $UV_{254}$ also showed higher values in the sidestreams and treatment facilities than mainstream indicating the presence of organic aromatic compounds. 2. Ratio of DOC on total organic carbon were higher in the mainstream which is attributable to the influent particulate organic materials produced by agricultural activities. The values were 10-15% higher in the mainstream compared with sidestreams. 3. Result of biodegradability test indicate that concentrations of recalcitrant DOC were higher in the sidestreams than in the mainstream. The values of recalcitrant DOC were higher with the forest stream indicating the effect of soil oriented humic substances. 4. Result of THM production test carried out at 10 stations in the Nakdong river show that $CHCl_3$ was detected with the highest value and the value was highest at Waekwan station.

• Fashion & Textile Research Journal
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• v.20 no.1
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• pp.1-9
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• 2018

This study has its purpose in classifying the ways in which transparent materials appear in clothes creating a sample garment on this basis, and studying the formative characteristics of human body expression through materials. The study methods for this study are: first, related documents and precedent theses were researched. Second, the expression methods of transparent materials shown in the clothes collection were classified through objective research. Transparent refers to the lexical definition of being see-through, and the transparency of materials arises from the chemical components and physical characteristics of its raw materials. Transparent materials have been applied to clothes and expressed in diverse ways, revealing the beauty of the human body. Such expression methods of transparent materials are classified by the 'degree of transparency', 'presence of patterns', and 'range of use'. In clothes, transparent materials are depicted through 'revealing' which exposes the body, 'making seemingly lighter' which makes the body livelier, and 'overlapping' which overlaps the body with the structure and patterns of the material. Furthermore, transparent materials express the human body through having the beholder 'peep' into other parts of the body, 'imagine' areas which are covered by looking at the areas which are exposed, and through 'blurring' the boundaries or the shape of the human body, depending on the degree of transparency. As such, the study of the expression methods of transparent materials and human expression has its importance in that it explores the expression methods of materials and formative characteristics of human body expression through these methods.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.10
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• pp.1351-1357
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• 2010

Water monitoring equipments using daphnia can be used to monitor the pollution levels of a country's main rivers. Such equipments should be capable of providing a prompt warning about increase in the contamination levels, which is evaluated on the basis of impulse number or toxicity index. As unmanned remote control equipments, they must provide reliable pollution monitoring results for each season and for the annual physical changes in each river. Two different equipments based on the impulse number and toxicity index showed different results for the operating rates and for the number of emergency checks required even though both were operated at the same conditions. The results are affected by many parameters such as the presence of any air bubbles and the microscopic pressure. The purpose of this study is to develop a method that can reduce the effect of bubbles or microscopic pressure on the monitoring data. We expect to achieve reliable monitoring data for water pollutants irrespective of the location of the equipment setup.

• The Korean Journal of Nuclear Medicine
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• v.26 no.1
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• pp.133-139
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• 1992

To improve the quality of $^{99m}Tc-methylenediphonate$ $(^{99m}Tc-MDP)$ for skeletal imaging, different composed $^{99m}Tc-MDP$ complexes were prepared with addition of antioxidants such as ascorbic acid, getisic acid, and p-aminobenzoic acid. To characterize the different $^{99m}Tc-MDP$ preparations, some physical and biochemical properties of $^{99m}Tc-MDP$ such as thermal stability, lipophilicity and bindability to serum protein were studied and organ distribution pattern of these complexes also compared. The thermal stabilities of $^{99m}Tc-MDP$ contained antioxidants were dependant mainly on pH, temperature, and elapsed time after the preparation. $^{99m}Tc-MDP$ complex contained gentisic acid as antioxidant was extremely unstable at alkaline condition. The most stable $^{99m}Tc-MDP$ was found in the presence of p-aminobenzoic acid. $^{99m}Tc-MDP$ complexes with antioxidants were very lipophilic but lipophilicity differences in antioxidants were not observed. The bindability of $^{99m}Tc-MDP$ to serum protein was not affect at pH $5.0\sim9.0$ by the different antioxidants. However, protein binding percentage of $^{99m}Tc-MDP$ with ascorbic acid was relatively low (22.7%) at pH 9.0. In biodistribution studies in mice, bone to muscle ratios of $^{99m}Tc-MDP$ preparations containing ascorbic acid, gentisic acid, and p-aminobenzoic acid were 15.3, 24.5, and 30.1, respectively. Im to our results, p-aminobenzoic acid is fond to be the most promising antioxidant.

• Journal of Preventive Medicine and Public Health
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• v.50 no.4
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• pp.240-250
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• 2017

Objectives: Subjective life expectancy (SLE) has been found to show a significant association with mortality. In this study, we aimed to investigate the major factors affecting SLE. We also examined whether any differences existed between SLE and actuarial life expectancy (LE) in Korea. Methods: A cross-sectional survey of 1000 individuals in Korea aged 20-59 was conducted. Participants were asked about SLE via a self-reported questionnaire. LE from the National Health Insurance database in Korea was used to evaluate differences between SLE and actuarial LE. Age-adjusted least-squares means, correlations, and regression analyses were used to test the relationship of SLE with four categories of predictors: demographic factors, socioeconomic factors, health behaviors, and psychosocial factors. Results: Among the 1000 participants, women (mean SLE, 83.43 years; 95% confidence interval, 82.41 to 84.46 years; 48% of the total sample) had an expected LE 1.59 years longer than that of men. The socioeconomic factors of household income and housing arrangements were related to SLE. Among the health behaviors, smoking status, alcohol status, and physical activity were associated with SLE. Among the psychosocial factors, stress, self-rated health, and social connectedness were related to SLE. SLE had a positive correlation with actuarial estimates (r=0.61, p<0.001). Gender, household income, history of smoking, and distress were related to the presence of a gap between SLE and actuarial LE. Conclusions: Demographic factors, socioeconomic factors, health behaviors, and psychosocial factors showed significant associations with SLE, in the expected directions. Further studies are needed to determine the reasons for these results.

• Journal of Oriental Neuropsychiatry
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• v.25 no.3
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• pp.225-234
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• 2014

Objectives: The purpose of this study is to investigate the effects of M&L Self-Growth Meditation Program with Euro QOL-5 Dimension (EQ5D), Five Facet Mindfulness Questionnaire (FFMQ) and psychological test. Methods: 6 middle-age women have participated in the eight weeks of the M&L Self-Growth Meditation Program, and the program was executed once a week for about two hours. We evaluated EQ5D, FFMQ, Beck Depression Inventory (BDI), State-Trait Anxiety Inventory (STAI), and State-Trait Anger Expression Inventory (STAXI) before and after the program in order to analyze the effects of M&L Self-Growth Meditation Program. Results: 1) EQ5D scores increased significantly (p<0.05), and overall physical condition scale( VAS) increased. 2) In the FFQM scores, value of Nonreactivity increased significantly (p<0.05), and total score increased. 3) Scores of BDI and STAI-S decreased significantly (p<0.05), and STAI-T, STAXI-S, STAXI-T, STAXI-O, STAXI-Su, and STAXI-R decreased. Conclusions: The results suggested that M&L Self-Growth Meditation Program improves the quality of life and mindfulness skill and has a positive responses to psychological problems-depression, anxiety, and anger.

• Journal of Oriental Neuropsychiatry
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• v.27 no.4
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• pp.235-248
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• 2016

Objectives: The aim of this review was to investigate whether evidence of complementary and alternative medicine (CAM) was reflected in clinical practice guidelines (CPGs) for insomnia based on relevant clinical trials. Methods: We conducted a systematic search on domestic and international CPG databases and medical databases. In addition, we conducted manual searches of relevant articles. Three authors independently searched and selected relevant studies; any disagreement was resolved by discussion. We extracted and analyzed the following data: published language, country, development group, participants, interventions, presence or absence of recommendations for CAM, level of evidence, grade of recommendation for CAM, and methods of development. Results: We identified 8,241 records from domestic and international databases, and 22 CPGs were included. Eleven of the 22 CPGs mentioned CAM interventions including herbal medicine, relaxation, acupuncture moxibustion, Tai Chi, meditation, hypnosis, biofeedback, Tuina, and external herbal medicine. However, most of the CPGs indicated 'no recommendation' or 'weak recommendation' for CAM interventions. Only Valeriana dageletiana Nakai and relaxation were considered to have experimental evidence. Valeriana dageletiana Nakai was recommended for improvement of sleep latency, sleep maintenance, total sleeping time, and sleep cycle. Relaxation was recommended as effective intervention for relieving physical and psychological arousal. Conclusions: Despite systematic reviews and randomized controlled trials on CAM for insomnia, most of the CPGs for insomnia did not reflect the evidence obtained. Further CPGs for insomnia should be developed by considering the current advanced studies in the field of CAM.

• Journal of the Korean Society of School Health
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• v.33 no.1
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• pp.28-38
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• 2020

Purpose: This study aimed to identify the prevalence of alcohol and cigarette use and assess its relationship with socio-environmental, psychological, violent and behavioral factors among a sample of high school students from Lima and Callao, Peru. Methods: We utilized the data from a cross-sectional study conducted by the Yonsei Global Health Center in collaboration with the Korea International Cooperation Agency (KOICA) Peru office in November 2016. The total sample size of this study was 1,477 students. For analysis, we used bivariate and multivariate logistic regression to calculate the unadjusted and adjusted odds ratios and their respective 95% confidence intervals. Results: The current prevalence of alcohol and cigarette use among adolescents was found to be 24.2% and 12.1%, respectively. Alcohol use was affected by age, friends' alcohol use, experience of physical fighting, and involvement in other risk behaviors (smoking, drug use, and sexual intercourse). Cigarette use was affected by perceived academic performance, friends' cigarette use, and involvement in other risk behaviors (drinking, drug use, and sexual intercourse). Furthermore, students who received affection from their parents and whose parents monitored their activities were less likely to report using both alcohol and cigarettes. Conclusion: Alcohol and cigarette use among Lima and Callao adolescents is affected by socio-environmental, violent and behavioral factors. Alcohol and cigarette use prevention initiatives should promote positive parenting practices, family togetherness, and a supportive school climate. In addition, it is needed to establish peer-led programs that promote behavioral changes in students and strengthen social relations without the presence of alcohol, cigarettes, and other harmful substances.

• Journal of Conservation Science
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• v.36 no.1
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• pp.15-27
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• 2020

The Main Hall of the Fengguo monastery in Yixian county, Liaoning province, China, is the best preserved and largest wooden Buddhist structure, typical of the Liao dynasty style, in China. However, some degradation to the timber frame of the Main Hall has been noted, and this is causing concern in terms of the long-term preservation of the structure. In this study, wooden pillars showing the degradation phenomena of whitening, for areas in contact with the stone floor, and extensive surface damage at higher locations(mostly above 1 m) have been examined. Samples taken from wooden pillar surfaces were analyzed using X-ray powder diffraction, Fourier-transform infrared spectroscopy(FTIR), ion chromatography, and pH measurements. With respect to the whitening phenomenon, we found inorganic calcium precipitates and oxalate ions, along with higher pH values. These symptoms indicated that chemical changes were taking place in response to alkaline conditions, suggesting that alkaline mixtures with calcium content in the foundations may be responsible. Regarding the upper surface-damaged areas, no valid evidence for chemical degradation was found using FTIR analysis, while damaged areas exhibited the presence of more bat guano-related materials than which were apparent in undamaged areas. The occurrence of this surface-damaged phenomenon has therefore been attributed to physical damage caused by bat activity over long periods of time.