• Bulletin of the Korean Chemical Society
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• v.31 no.10
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• pp.2849-2853
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• 2010

A method to improve the photocatalytic activity of titanium dioxide by modification with a sensitizer and a metal oxide is proposed. To achieve this goal, we used metal oxides as dopants. In particular, $CaWO_4$ and $Gd_2O_2S$:Tb were used because their 2.6 eV and 2.2 eV band gap energy and optical properties have a large positive effect on photocatalysis. The improvement in the photocatalytic activity of $TiO_2$ modified with $Gd_2O_2S$:Tb under ultraviolet light irradiation is described in a previous study. The present work focuses on the sensitization of metal oxide-modified $TiO_2$. Having observed the ultraviolet-visible absorption spectra of 3,4,9,10-Perylenetetracarboxylic diimide in the wide visible-light region from 400 nm to 650 nm and the broad peaks in its photoluminescence spectra at 695 nm and 717 nm, we decided to use this perylene dye to sensitize modified $TiO_2$ to enhance its activity as a visible-light harvesting photocatalyst. We also explored the positive effects thin-film surface changes stemming from ultraviolet pre-treatment have on photocatalytic activity. Finally, we subjected several metal oxide-modified $TiO_2$ products sensitized by the perylene dye to ultraviolet pre-treatment, obtaining the most active photocatalysts.

• Perspectives in Nursing Science
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• v.13 no.2
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• pp.70-80
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• 2016

Purpose: This study examined the relationship between acculturation stress and health promotion behaviors in the Korean Chinese elderly immigrants living in Korea, focusing on the buffering effects of social support. Methods: We included 132 completed questionnaires in the analysis. The buffering effect was examined using a hierarchical regression analysis by adding interaction terms. Results: Health promotion scores were significantly higher in the group with a higher education level, lower depressive symptom scores, and higher levels of social support. However, no statistically significant differences were found in the health promotion behaviors by gender, age, spouse, job, financial stability, subjective health status, chronic disease, regular health checkups, or acculturation stress. The hierarchical regression analysis demonstrated that social support had a buffering effect on the relationship between acculturation stress and health promotion behaviors in the Korean Chinese elderly immigrants. Specifically, the relationship between the acculturation stress stemming from the difficulties in the workplace and health promotion behaviors was attenuated by social support. Conclusion: These findings indicate that social support significantly moderates the relationship between acculturation stress and health promotion behaviors in the Korean Chinese elderly immigrants living in Korea. A variety of strategies to enhance social support should be incorporated in the health promotion programs to decrease the negative effects of acculturation stress in the Korean Chinese elderly living in Korea.

• Korean Journal of Social Welfare
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• v.42
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• pp.41-82
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• 2000

The purpose of this study is to provide empirical findings about intragenerational and intergenerational discrepancies in eldercare attitude and behavior in Korea. Specifically, intragenerational discrepancies refer to phenomena in which eldercare attitude and behavior diverge from each other within the caregiving and care-receiving generations, respectively. Intergenerational discrepancies, on the other hand, refer to two kinds of phenomena, one in which eldercare attitudes are different between caregiver and care-receiver and the other in which eldercare behavior is differently recognized between the two parties. For the last couple decades, these kinds of discrepancies tended to be simply assumed without any coherent theoretical and/or empirical rationales. Thus, the current study tried to investigate the degree, pattern, and characteristics associated with the discrepancies. Analysis of data collected from 276 matched pairs of caregivers (i.e., daughters-in-law) and care-receivers (i.e., the elderly) in Kwangju and its suburb areas has indicated a substantial amount of both intra- and inter-generational discrepancies. In other words, both caregivers and care-receivers were found to be experiencing huge discrepancies between attitude and behavior in their respective generation: the factual discrepancies in attitude between the two generations were quite salient: the cognitive discrepancies in behavior between them were salient, too. In addition, it was also found' that the extent to which the discrepancies became salient differed for the three subdimensions of eldercare (i.e., emotional, economic, and physical care), and that such discrepancies have intimate relationships with a set of sociodemographic characteristics for caregivers - notably, age, educational attainment, area of residence, household income - on the one hand, and those for care-receivers - notably, gender, age, educational attainment, cohabitation, family size, inheritance, owned property - on the other. A series of theoretical, empirical, and clinical implications stemming from the findings were suggested and fully discussed in the context of Korean society.

• Nuclear Engineering and Technology
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• v.44 no.5
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• pp.551-560
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• 2012

The Wolsong-1 (W-1) Phase-B pre-simulations were carried out in preparation for tests to be conducted for the restart of the reactor after a major refurbishment project that included replacement of the pressure tube. These pre-simulations for Wolsong-1 Phase-B differ from those in the past that were performed for the Wolsong-1,2,3,4 tests in that these tests use the WIMS/DRAGON/RFSP-IST code suite for verification of the tests and gadolinium instead of the traditional PPV/MULTICELL/RFSP code system and boron as poison in the moderator system. The use of gadolinium is deemed not to have domestically accumulated experience gained from the previous Phase-B tests. Thus, it is appropriate to conduct a study in order to gain a correct understanding and interpretation of potential differences in test results stemming from using gadolinium rather than boron. Although the calibration of the reactivity device will not be noticeably different using boron and gadolinium at a constant moderator temperature, the temperature dependency of the neutronic behavior due to the presence of gadolinium in the moderator system might be pronounced. The results of the pre-simulations using gadolinium revealed that the moderator temperature reactivity coefficients indeed showed significant differences in comparison with those with boron. In order to secure the validity of the analysis results, the newly acquired WIMS/DRAGON/RFSP-IST code suite was verified against the W-2,3,4 Phase-B test results. The results of the new code suite verifications revealed some overall improvements in accuracy; justification of the use of the code can be claimed for the validation of the W-1 Phase-B test results.

• KIEAE Journal
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• v.10 no.1
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• pp.73-83
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• 2010

In urban regeneration, resident participation and respect of residents' need have become a major important issue. The purpose of this study is to identify residential area improvement characteristics expected by local residents. Data used for this study were collected from survey which used questionnaire and village image map construction tool kit, developed for facilitating the residents' participation in an actual housing improvement area at Kwngjoo, Korea. The major contents surveyed through questionnaire were first, future images of the area second, directions of improvement third, preferred architectural types such as high or low rise buildings. and a total of 335 data was collected within 4 days during 12-14 December, 2008. The kit was used by parents of students at a local elementary school, and 205 image maps were collected. Content analysis was to analyse characteristics of villages shown in the constructed image maps. Lynch's five elements were utilized to select areas for analysis. As a result, types of buildings desired by residents at the selected four local areas were identified. In general, residents desired their village to be improved with low and mid rise buildings, respecting existing cultural assets. This study showed that there is certain characteristics in relation to the selected areas. Besides, the tool kit used this study showed the effectiveness in collecting opinions from young households in the improvement area within a short time. The tool is expected to be useful in attracting residents and in facilitating participation of wide range of local residents by improving the constraints stemming from time and space.

• Journal of the Microelectronics and Packaging Society
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• v.19 no.2
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• pp.55-59
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• 2012

Defects such as voids or seams are frequently found in TSV via filling process. To achieve defect-free copper via filling, organic additives such as suppressor, accelerator and leveler were necessary in a copper plating bath. However, by-products stemming from the breakdown of these organic additives reduce the lifetime of the devices and plating solutions. In this research, the effects of levelers on copper electrodeposition were investigated without suppressor and accelerator to lower the concentration of additives. Threelevelers(janus green B, methylene violet, diazine black) were investigated to study the effects of levelers on copper deposition. Electrochemical behaviors of these levelers were different in terms of deposition rate. Filling performances were analyzed by cross sectional images and its characteristics were different with variations of levelers.

• Journal of the Korean Society of Clothing and Textiles
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• v.27 no.3_4
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• pp.343-353
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• 2003

In this research, the fashion images, which expressed the same theme during the same season in four different fashion collections, were interpreted as emotional characteristics stemming from different factors according to the emotions and images of the regions where the collections were held. The theme, futurism appeared to be hackneyed and oppressive in Paris fashion which emphasized artistic representation of the theme. And futurism appeared to be expressed to be dazzling, unnatural in London fashion which was innovative and avant-garde. And the New York fashion, which accentuated practical, sportive, and elegant styles created active and graceful image about the futurism and the Milan fashion showed the balanced mixture of the three cities' images above. It is interpreted that our domestic fashion consumers think artistic, formative, original, and emotional images as hackneyed and oppressive. On the other hand, they feel comfortable, cheerful, unaffected and graceful about the images that are functional (rather than artistic), sportive, and moderately elegant. And the innovative and avant-garde images like the ones in London collection seem to make people feel unnatural, dazzled, and even depressed. In short, domestic fashion consumers think that the excessive, innovative, original, and formative fashion images appeared I London and Paris are hackneyed and dark rather than artistic, original, or dynamic. On the contrary, the moderate, practical, sportive and elegant New York images and the Milan's which equally showed the three cities' characteristics are regarded as comfortable, elegant, bright, and positive. This result indicates that the fashion market in certain regions seek shared fashion trends and the difference between the regions reflects the different interpretation of fashion themes.

• Journal of Astronomy and Space Sciences
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• v.33 no.4
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• pp.279-285
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• 2016

The space radiation dose over air routes including polar routes should be carefully considered, especially when space weather shows sudden disturbances such as coronal mass ejections (CMEs), flares, and accompanying solar energetic particle events. We recently established a heliocentric potential (HCP) prediction model for real-time operation of the CARI-6 and CARI-6M programs. Specifically, the HCP value is used as a critical input value in the CARI-6/6M programs, which estimate the aviation route dose based on the effective dose rate. The CARI-6/6M approach is the most widely used technique, and the programs can be obtained from the U.S. Federal Aviation Administration (FAA). However, HCP values are given at a one month delay on the FAA official webpage, which makes it difficult to obtain real-time information on the aviation route dose. In order to overcome this critical limitation regarding the time delay for space weather customers, we developed a HCP prediction model based on sunspot number variations (Hwang et al. 2015). In this paper, we focus on improvements to our HCP prediction model and update it with neutron monitoring data. We found that the most accurate method to derive the HCP value involves (1) real-time daily sunspot assessments, (2) predictions of the daily HCP by our prediction algorithm, and (3) calculations of the resultant daily effective dose rate. Additionally, we also derived the HCP prediction algorithm in this paper by using ground neutron counts. With the compensation stemming from the use of ground neutron count data, the newly developed HCP prediction model was improved.

• Journal of KIISE:Information Networking
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• v.37 no.5
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• pp.386-395
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• 2010

Widespread deployment of infrastructure WLANs has made Wi-Fi an integral part of today's Internet access technology. Despite its crucial role in affecting end-to-end performance, past research has focused on MAC protocol enhancement, analysis, and simulation-based performance evaluation without sufficiently considering a misbehavior stemming from capture effect. It is well known that the capture effect occurs frequently in wireless environment and incurs throughput unfairness between nodes. In this paper, we propose a novel Fair MAC algorithm which achieves fairness even under physically unfair environment. While satisfying the fairness, the proposed algorithm maximizes the system throughput. Extensive simulation results show that the proposed Fair MAC algorithm substantially improves fairness without throughput reduction.

• Solar Energy
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• v.15 no.2
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• pp.3-11
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• 1995

This paper reports the performance of solar domestic hot water systems manufactured with heat pipes. A series of tests were conducted on a number of systems to elicit the most suitable configuration of the system for possible commercialization in Korea. The heat pipe is made with a copper tube and the respective length of the evaporator, adiabatic, and condenser sections are 1700mm, 100mm and 200mm. The evaportor section is finned with a copper plate to increase solar input for its proper operation as a heat pipe. Results show quite an interesting performance data stemming from the difference in working fluids, presence of wick, and other various design parameters associated with the collection and utilization of solar energy.