• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.6
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• pp.1479-1495
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• 2012

Spectrum scarcity seems to be the most challenging issue to be solved in new wireless telecommunication services. It is shown that spectrum unavailability is mainly due to spectrum inefficient utilization and inappropriate physical layer execution rather than spectrum shortage. Daily increasing demand for new wireless services with higher data rate and QoS level makes the upgrade of the physical layer modulation techniques inevitable. Orthogonal Frequency Division Multiple Access (OFDMA) which utilizes multicarrier modulation to provide higher data rates with the capability of flexible resource allocation, although has widely been used in current wireless systems and standards, seems not to be the best candidate for cognitive radio systems. Filter Bank based Multi-Carrier (FBMC) is an evolutionary scheme with some advantages over the widely-used OFDM multicarrier technique. In this paper, we focus on the total throughput improvement of a cognitive radio network using FBMC modulation. Along with this modulation scheme, we propose a novel uplink radio resource allocation algorithm in which fairness issue is also considered. Moreover, the average throughput of the proposed FBMC based cognitive radio is compared to a conventional OFDM system in order to illustrate the efficiency of using FBMC in future cognitive radio systems. Simulation results show that in comparison with the state of the art two algorithms (namely, Shaat and Wang) our proposed algorithm achieves higher throughputs and a better fairness for cognitive radio applications.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.407-407
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• 2019

According to Asian Development Bank report Pakistan is among water scarce countries. Climate scenario on the basis IPCC fifth assessment report (AR5) revealed that annual mean temperature of Pakistan from year 2010-2019 was $17C^o$ which will rise up to $21C^o$ at the end of this century, similarly almost 10% decrease of annual rainfall is expected at the end of the century. It is a changing task in underdeveloped countries like Pakistan to meet the water demands of rapidly increasing population in a changing climate. While many studies have tackled scarcity and stream flow forecasting of the Upper Indus Basin (UIB) Pakistan, very few of them are related to socio-economic and climate change impact on sustainable water management of UIB. This study investigates the pattern of current and future surface water availability for various demand sites (e.g. domestic, agriculture and industrial) under different socio-economic and climate change scenarios in Upper Indus Basin (UIB) Pakistan for a period of 2010 to 2050. A state-of-the-art planning tool Water Evaluation and Planning (WEAP) is used to analyze the dynamics of current and future water demand. The stream flow data of five sub catchment (Astore, Gilgit, Hunza, Shigar and Shoyke) and entire UIB were calibrated and validated for the year of 2006 to 2011 using WEAP. The Nash Sutcliffe coefficient and coefficient of determination is achieved ranging from 0.63 to 0.92. The results indicate that unmet water demand is likely to increase severe threshold and the external driving forces e.g. socio-economic and climate change will create a gap between supply and demand of water.

• Journal of the Korea society of information convergence
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• v.6 no.2
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• pp.23-44
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• 2013

First, the average scores of personal financial management ability in the college students' financial management attitude were 72.24 for male and 71.65 for female, so that male students showed a little higher score than female. College students who had an experience of opening a bank account and who kept a record of spending revealed higher scores. Those whose parents were elementary or middle school graduates unfolded the highest score, 73.67, and the lowest score, 63.35, from those whose parents had M.A. or Ph.D. The average scores of personal financial management ability in the college students' financial management knowledge indicated almost no difference with 63.26 for male and 63.35 for female. Only whether they had an experience of opening a bank account, keeping a record of spending, or a credit card revealed score differences. Depending on the students' majors, there were also score differences. Students from engineering department came up with the highest score, an average of 66.88, and students from art & physical education department with the lowest score, 53.39, in the financial management knowledge. The personal financial management ability in the college students' financial management function showed that the score of male students was a little higher than that of female, 64.26 versus 63.58. Students who kept a record of spending and whose parents' income was between three million won and four million won marked the highest score, an average of 65.26, and students whose parents' income was below two million won marked the lowest score, an average of 60.43, in the college students' financial management function. There were score differences in the college students' financial management function depending on the students' majors. Students from engineering department came up with the highest score, an average of 69.67, and students from public health department with the lowest score, 63.21.

• Journal of Conservation Science
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• v.32 no.2
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• pp.249-259
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• 2016

Effect of the flame retardants on Dancheong is studied in the present work. Two kinds of flame retardants were applied on Dancheong specimens and compared with control groups on which distilled water was applied instead of the flame retardants. The flame retardants enhanced the hygroscopic property of the surface of Dancheong. Furthermore, the added flame retardants reacted with oyster shell white($CaCO_3$) and lead red($Pb_3O_4$), producing new chemical compounds like Calcium phosphate tribasic and Lead Phosphates which make the painted layer of Dancheong dissolving and whitening over certain period of time. When applied in excessive amount and exposed in repetitive wet and dry condition, especially, they aggravate the surface problems significantly. These results will provide a good reference on the study of the discoloring/whitening effect of Dancheong layers at many traditional wooden building in Korea.

• 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.773-782
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• 2019

Basel III (Third Basel Accord or Basel Standards) is a global, voluntary regulatory framework on bank capital adequacy, stress testing, and market liquidity risk. Basel III regulatory ratios include capital adequacy, asset soundness, and liquidity. The capital adequacy variables include BIS capital adequacy ratio, BIS tier 1 capital ratio, and tangible common equity ratio. The asset soundness variables include non-performing loan ratio and non-performing loan coverage ratio. The liquidity regulation variables include KRW liquidity coverage ratio and foreign currency liquidity coverage ratio. This study aims to investigate how capital adequacy standard affects efficiency of internet primary banks. As a result of this study, BIS capital adequacy ratio of domestic internet primary banks is lower than that of commercial banks. In order to maintain sustainable operation considering capital adequacy regulations, it is necessary to expand additional capital. In addition, the delinquency rate and non-performing loan ratio of domestic internet primary banks is gradually increasing due to the maturity of high-yield loans in 2019.

• Journal of Physiology & Pathology in Korean Medicine
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• v.33 no.2
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• pp.141-150
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• 2019

Despite the development of assisted reproduction technologies (ART) including in vitro fertilization (IVF), the poor ovarian response and endometrial receptivity remains clinically a major unmet need. Although these problems are difficulties to solve in infertility treatment, there are no good therapeutic option yet. Traditional herbal remedies and acupuncture, therefore are being proposed as alternative treatment. Our group found that traditional herbal medicines such as Paeonia lactiflora L.(PL, 芍藥), Cyperus rotundus L.(CR, 香附子), and Perilla frutescens (PF, 紫蘇葉) could improve endometrial receptivity. In this study, we found out Yeosin-san (如神散) as an optimal herbal formula via combination of the previously established herbal medicines. Yeosin-san is a traditional Korean medical formula which was established by Ziming Jin (陳自明) and recorded in Furendaiquanliangfang (婦人大全良方) at first. The formula traditionally used for treating abnormal uterine bleeding and leukorrhea. It showed a highest effect on leukemia inhibitory factor (LIF) expression and on the adhesion between trophoblastic cells and endometrial cells. In addition, it has been shown that the Yeosin-san not only increases the endometrial receptivity to improve the embryo implantation but also enhances the ovary function by expressing the angiogenesis-related genes. Here we suggest that Yeosin-san could be a novel and effective candidate for treating female infertility.

• Journal of Conservation Science
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• v.35 no.3
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• pp.237-244
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• 2019

In this study, we applied terahertz imaging technology to three Korean modern oil paintings ('Boy,' 'Girl,' and 'Hyehwadong Landscape'); investigated the types of inner layer information in the pictures that can be extracted with terahertz imaging technology; and analyzed the conditions for extracting them. The biggest problem in the terahertz imaging analysis we encountered was the image distortion caused by the change of the distance between the target surface and the terahertz detector, depending on the surface curvature of the target paintings. We then developed a 'working distance maintaining device' to solve this problem. As a result, the terahertz imaging technique was used to identify the base material characteristics and any patterns of damage inside, and presented the optimal conditions for identifying each characteristic. In addition, it was useful to employ the terahertz frequency-division image to check the characteristics of the background materials. To confirm coloring techniques such as brush strokes, it is effective to compare the maximum reflection peak image with the cross-section image; and to detect damage information inside the paintings that cannot be observed on the surface, to compare the cross-section image with the frequency-division image. On the other hand, according to the terahertz imaging analysis of the oil paintings, the internal structural damage marks of 'Boy' and 'Girl' were confirmed, and the artist's painting style was confirmed in 'Hyehwadong Landscape.' The above results are expected to be useful for the analysis and diagnosis of Korean modern oil paintings for their preservation.

• Clinical and Experimental Pediatrics
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• v.64 no.12
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• pp.632-641
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• 2021

Background: Over the past few decades, various goals have been defined to reduce the mortality of children caused by acute lower respiratory infections (ALRIs) worldwide. However, few spatial studies to date have reported on ALRI deaths. Purpose: We aimed to assess the spatial modeling of mortality from ALRI in children under 5 years of age during 2000-2017 using a global data. Methods: The data on the mortality of children under 5 years old caused by ALRI were initially obtained from the official website of the World Health Organization. The income status of their home countries was also gathered from the Country Income Groups (World Bank Classification) website and divided into 5 categories. After that, in the ArcGIS 10.6 environment, a database was created and the statistical tests and related maps were extracted. The Global Moran's I statistic, Getis-Ord Gi statistic, and geographically weighted regression were used for the analyses. In this study, higher z scores indicated the hot spots, while lower z scores indicated the cold spots. Results: In 2000-2017, child mortality showed a downward trend from 17.6 per 100,000 children to 8.1 and had a clustered pattern. Hot spots were concentrated in Asia in 2000 but shifted toward African countries by 2017. A cold spot that formed in Europe in 2007 showed an ascending trend by 2017. Based on the results of geographically weighted regression test, the regions identified as the hot spots of mortality from ALRI in children under 5 years old were among the middle-income countries (R²=0.01, adjusted R²=8.77). Conclusion: While the total number of child deaths in 2000-2017 has decreased, the number of hot spots has increased among countries. This study also concluded that, during the study period, Central and Western Africa countries became the main new hot spots of deaths from ALRI.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.7 no.1
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• pp.253-263
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• 2017

As needs for knowledge on Korean history and the attention of the people are rapidly increasing, various smartphone applications for learning the history have appeared during recent years. These applications provide multiple choice questions to users through their own problem banks. But, since these questions are selected from the fixed set of problems that are stored previously, the learning efficiency of users is inevitably decreased when they use the applications repeatedly. In this paper, we present a question generation system named K-History which generates multiple choice questions in an automatic way using the database on the history of Korea. In addition, we also describe the development of the application Korean History Infinite Challenge as a learning application for Korean history. To develop K-History, we classify typical types of learning problems through various problems based on Korean history learning materials, proposing algorithms to generate problems according to the types found. Through the developed techniques, various learning systems can reduce the cost for creating questions, while increasing the learning efficiency of users.

• Conservation Science in Museum
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• v.13
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• pp.23-31
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• 2012

The object artifacts of this study are the iron artifacts owned by the Kyunghee University Central Museum. The surfaces of the iron artifacts are opaque due to the coated materials which are presumed to be paraffin or bee's wax while they are plate-shaped and exist in thickly exfoliated condition caused by severe corrosion developed on the overall surfaces. Therefore, in order to remove the coated materials away from the surfaces of the artifacts rather safely, reversibility tests have been carried out and the conservation treatment was performed upon the basis of and in application of the experimental results. The study methodologies are that: first, the FT-IR analysis was carried out to determine the ingredients of the coating-treated material on the surface; second, by applying various kinds of organic solvents, the kinds of agents that allow the artifact's surface-coating material to be reversible have been identified through experiments; third, the most suitable agent for removing coating material was selected and applied to the real artifacts on the basis of the results of the reversibility tests. Results from the study: first, as a result of the FT-IR analysis, the coating agent used on the artifacts was identified to be of the same ingredients as those of paraffin; second, among organic solvents, xylene, toluene, trichloroethylene and methyl alcohol were identified to be usable for dissolving paraffin whereas toluene was judged to be the most suitable for removing the coating agent; third, when applying the selected agents on the real artifacts, due to the fact that removing the whole paraffin might cause the artifact to disintegrate, the paraffin of only the part that covered the surfaces opaquely was removed using cotton swab or gauze, thus completing the conservation treatment.