• Korean Journal of Remote Sensing
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• v.34 no.6_2
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• pp.1273-1282
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• 2018

Recently, active research on the Arctic Ocean has been conducted due to the influence of global warming and new Arctic ship route. Although previous studies already calculated quantitative extent of sea ice using passive microwave radiometers, melting at the edge of sea ice and surface roughness were hardly considered due to low spatial resolution. Since Sentienl-1A/B data in Extended Wide (EW) mode are being distributed as free of charge and bulk data for Arctic sea can be generated during a short period, the entire Arctic sea ice data can be covered in high spatial resolution by mosaicking bulk data. However, Sentinel-1A/B data in EW mode, especially in HV polarization, needs significant radiometric correction for further classification. Thus, in this study, we developed algorithms that can correct thermal noise and scalloping effects, and confirmed that Arctic sea ice and open-water were well classified using the corrected dual-polarization SAR data.

• Journal of the korean academy of Pediatric Dentistry
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• v.46 no.2
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• pp.209-218
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• 2019

This study was aimed to evaluate orofacial morphologies on the cases of developmental disorders of maxillary first molars. Panoramic radiographs, lateral cephalographs, and clinical photos of 2983 children who attended the Pediatric Dental Clinic of Pusan National University Dental Hospital from 2006 to August 2017 were assessed retrospectively. 34 patients were selected whose maxillary first molars were missed or developmentally delayed unilaterally or bilaterally. Demirjian's method was used for estimating dental age, then which was compared to chronologic age of children. Parameters expressing skeletal and dentoalveolar disharmony were checked and compared with control. Additionally, occlusion relationship was evaluated. Maxillary dental age was significantly delayed compared to chronologic age. Several parameters which show skeletal open-bite tendency and skeletal class III malocclusion with maxillary retrusion were statistically significant. Anterior crossbite and edge-bite were expected in most of these cases, but compensation by occlusion and soft tissue was also verified which might mask skeletal class III tendency. Congenital missed or developmentally delayed maxillary first molars might be related with declined growth of maxilla. If developmental disorders of maxillary first molars were verified during clinical examination, careful monitoring of orofacial growth was necessary during puberty and timed orthopedic and orthodontic intervention were considered.

• Clean Technology
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• v.26 no.4
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• pp.311-320
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• 2020

In this study, the photocatalytic degradation of rhodamine B (RhB), methyl orange (MO) and methylene blue (MB) was carried out under visible light irradiation using CdS and CdZnS/ZnO photocatalysts prepared by a simple precipitation method. This study focused on examining the effect of physicochemical properties of dye and photocatalyst on the reaction pathway of photocatalytic degradation. The prepared photocatalysts were characterized by XRD, UV-vis DRS and XPS. Both the CdS and CdZnS/ZnO photocatalysts exhibit an excellent absorption in the visible light and the UV light regions. It was observed that the photocatalytic degradation of MO proceeds via the same reaction mechanism on both the CdS and CdZnS/ZnO photocatalysts. However, the photocatalytic degradation of RhB and MB was found to proceed through a different reaction pathway on the CdS and CdZnS/ZnO catalysts. It is interesting to note that MB dimer was formed on the CdS catalyst at the beginning of the photocatalytic reaction, while the MB monomer was degraded during the overall photocatalytic reaction on CdZnS/ZnO. The above results may be mainly ascribed to the difference of band edge potential of the conduction band in the CdS and CdZnS/ZnO semiconductors and the adsorption property of dye on the catalysts.

• Journal of Korea Society of Industrial Information Systems
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• v.25 no.6
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• pp.33-45
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• 2020

This paper aims to look at the perspective that the latest cutting-edge technologies are predicting individual diseases in the actual medical environment in a situation where various types of wearable devices are rapidly increasing and used in the healthcare domain. Through the process of collecting, processing, and transmitting data by merging clinical data, genetic data, and life log data through a user-participating wearable device, it presents the process of connecting the learning model and the feedback model in the environment of the Deep Neural Network. In the case of the actual field that has undergone clinical trial procedures of medical IT occurring in such a high-tech medical field, the effect of a specific gene caused by metabolic syndrome on the disease is measured, and clinical information and life log data are merged to process different heterogeneous data. That is, it proves the objective suitability and certainty of the deep neural network of heterogeneous data, and through this, the performance evaluation according to the noise in the actual deep learning environment is performed. In the case of the automatic encoder, we proved that the accuracy and predicted value varying per 1,000 EPOCH are linearly changed several times with the increasing value of the variable.

• The Journal of the Korea Contents Association
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• v.21 no.3
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• pp.490-504
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• 2021

The online market is gradually increasing due to the increase in single-person households, the development of information and communication technologies, the emergence of various new products, and price comparison competition. Companies need differentiation strategies to adapt to changes in the online environment and secure a competitive edge. In this environment, the objective is to consider the importance of consumer perception of websites in order to generate continuous growth and revenue in the online market as well as to differentiate them from competitors using an online service environment that can affect consumers' internal responses. In this study, we present aesthetic, functional, privacy, and interaction factors as components of e-servicescape to study the impact of e-servicescape on website trust, brand attitude, and repurchase intention. In the data analysis, 485 ordinary people with online shopping experience were surveyed. The questionnaire was based on a 7-point Likert scale for each question and statistical analysis was conducted using SPSS 24.0 and AMOS 25.0. The analysis shows that in e-servicescapes aesthetic and privacy factors influence website trust and brand attitudes and consequently affect repurchase intention.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.40 no.3
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• pp.187-193
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• 2022

In the Yeongdong region of Gangwon-do, coastal areas are important resources in terms of cultural, social and economic aspects. However, the coast of Gangwon-do is experiencing severe erosion, and it is concerned that its adverse effects will gradually increase. In this study, coastline changes of Yangyang and Gangneung in Gangwon-do were tracked and analyzed over a long period of time. In order to build time series image data, aerial photos from the 1940s to the present were mainly used, and data from CORONA satellite, which operated from the 1960s to the early 1970s, were collected and used together. Using 51cm resolution ortho image and 2m resolution Digital Elevation Model(DEM) as reference, ground control points were selected to perform geometric correction on the aerial photos and CORONA images. Subsequently, Canny edge detector applied to these images to extract the coastlines. As a result of analyzing the extracted and vectorized coastlines by overlaying them in chronological order, erosion and deposition occurring around the artificial structures and on the nearby beaches were observed. In this study, the effect of seasonal variation, tide, and various coastal management including the beach filling were not considered. Because coastal erosion is greatly affected by geographic factors, each local government must find its own solution. Continuous research and local data accumulation are required.

• Communications of Mathematical Education
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• v.36 no.1
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• pp.73-88
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• 2022

Mathematics is a way of thinking. To do mathematics means to think mathematically. In other words, mathematics education and mathematics literacy are related. In elementary and secondary school mathematics education in many countries, teaching of mathematics using textbooks is conducted mostly in their native language. So mathematics education takes place while reading, writing, listening, and speaking mathematics. Analysis of mathematics textbooks for the lower grades of undergraduate mathematics shows that most advanced countries in mathematics use excellent undergraduate mathematics textbooks written in their native language. However, the ratio of using imported textbooks from foreign countries is particularly high in the case of textbooks for mathematics majors at Korean universities. In this article, the effect of language used in university mathematics education is analized. In particular, the importance of high-quality leading-edge university mathematics textbooks in native language is introduced by analyzing the case of Bourbaki in France and 'War of language' at the Israel Institute of Technology. The innovation of French university mathematics education in the 20th century began with Bourbaki's 'Fundamentals of Mathematics', a French textbook written in his native language. Israel's Technion and the Hebrew University of Jerusalem continue to teach all subjects in their mother tongue. This has led to produce many Nobel Prize and Fields medal winners in these two countries. This study shows that textbooks and languages used in university mathematics education has affected mathematical literacy.

• Korea Trade Review
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• v.42 no.4
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• pp.69-91
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• 2017

Since the global financial crisis, major countries have been executing policies related to two top-priority goals to create more jobs: revitalization of entrepreneur activity and the cultivation of small and medium-sized companies. In South Korea, the interest of policy makers is increasingly focusing on the role of SMEs that have a technological competitive edge in the realization of a "job-centered creative economy." Due to the nature of the field, the health and medical industry requires a particularly long time until the achievement of industrialization, Also, because of the complex distribution structure, it is essential for related government ministries and institutions to jointly devise strategies. A lack of policy supports for the industry has thus far resulted in its development being relegated for the most part of small and medium-sized companies, which consequently means low global competitiveness. Now is the time for the South Korean government to provide the revolutionary supported options and strategies. This study aims to propose a general policy direction and policy areas for the cultivation of Korea's small and medium-sized companies in the healthcare industry into global small giant companies through an exploration of the German case. It is crucial to first cultivate the international competitiveness of Korean small and medium-sized companies (as in the case of Germany) so that they can grow into global small giant companies. Another important task is the creation of an environment that expedites the qualitative growth of promising SMEs as well as technological development. After securing competitiveness in terms of both product quality and technology in the global health market, substantive policy supports will be necessary to cultivate global small giant companies that are export-based (e.g. job creation effect, sales value added).

• Korea Science and Art Forum
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• v.23
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• pp.347-358
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• 2016

The design of children's hospitals is highly dependent on color schemes. As a space shared together by both adults and children, the design of children's hospitals require color coordination that takes account of the users' characteristics. However, because the majority of prior research on color perception has focused overly on the emotional aspects, there is a necessity for more rational and scientific analyses to identify the characteristics of the visual perception of colors. Adopting this perspective in analyzing the characteristics of the visual perception of colors, this study aims to move beyond the abstract to focus on more objective methods, such as eye-tracking experiments, to examine the characteristics of hospital visitors' visual attention with respect to colors. Visual perception tracking experiment was conducted on the 2 chosen experimental images with a target group made up of adults and children, the following results were found. Firstly, spaces created with the preference colors of the different groups were found to develop a characteristic of developing higher attention. Secondly, observing the common tendencies for attention for adults and children, the highest region for visual concentration was formed towards the middle, as attention progresses to lower stages visually focused area changes in the order of upper-middle, left and right, and lower regions and edge regions show characteristics of not triggering attention Thirdly, it is understood that children's level of attention drops a lot faster than adults when identifying space therefore it is suspected that children need more elaborate color coordination than adults.

• Korean Journal of Mineralogy and Petrology
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• v.36 no.2
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• pp.107-115
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• 2023

Cobalt can be released into the natural environment as industrial waste from the alloying industry and as acid mine drainage, and it is also a radionuclide (⁶⁰Co) that constitutes high-level radioactive waste. Smectite is a mineral that can be useful for adsorption and isolation of this element. In this study, Cheto-type montmorillonite (Cheto-MM), which is the source clays of The Clay Mineral Society (CMS) and already well-characterized, was used. The effect of the adsorption site affected by the presence of interlayer water on the adsorption of cobalt before and after dehydration by heating was evaluated and the adsorption mechanism of cobalt on Cheto-MM was studied by applying adsorption kinetics and adsorption isotherm models. The results showed that the adsorption characteristics changed with dehydration and subsequent shrinkage, and cobalt was found to be adsorbed at the edge of Cheto-MM for about 38% and adsorbed at the interlayer site for about 62%, suggesting that the cobalt adsorption of Cheto-MM is significantly influenced by the interlayer. By applying the adsorption kinetic models, the cobalt adsorption kinetics of Cheto-MM is explained by a pseudo-second-order model, and the concentration-dependent adsorption was best described by the Langmuir isotherm adsorption model. This study provides basic knowledge on the adsorption characteristic of cobalt on montmorillonite with different adsorption sites and is expected to be useful in predicting the adsorption behavior of smectite in high-level radioactive waste disposal sites in the future.