• The Journal of Korean Association of Computer Education
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• v.11 no.5
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• pp.47-55
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• 2008

The Internet is one of the most infrastructure for information technology in school education. Providing the Internet with a proper bandwidth is an important element for efficient school education for information technology, especially because several instructional models based on new Internet technologies are under development. To support these instructional models, it is important for the schools to provide the proper Internet bandwidth wherever necessary. In this paper, the amount and pattern of internet usage in school were analyzed. Based on this analysis, we propose how to figure out a proper bandwidth for a different ladder of schools.

• Journal of Institute of Control, Robotics and Systems
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• v.13 no.8
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• pp.777-782
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• 2007

Human Robot Interaction(HRI) through a haptic interface plays an important role in controlling robot systems remotely. The augmented usage of bio-signals in the haptic interface is an emerging research area. To consider operator's state in HRI, we used bio-signals such as ECG and blood pressure in our proposed force reflection interface. The variation of operator's state is checked from the information processing of bio-signals. The statistical standard variation in the R-R intervals and blood pressure were used to adaptively adjust force reflection which is generated from environmental condition. To change the pattern of force reflection according to the state of the human operator is our main idea. A set of experiments show the promising results on our concepts of human adaptive interface.

• Bulletin of the Korean Chemical Society
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• v.33 no.1
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• pp.83-89
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• 2012

Due to the potential importance and usefulness, usage of highly ordered nanoporous anodized aluminum oxide can be broadened in industry, when highly ordered anodized aluminum oxide can be placed on a substrate with controlled thickness. Here we report a facile route to highly ordered nanoporous alumina with the thickness of hundreds-of-nanometer on a silicon wafer substrate. Hexagonally or tetragonally ordered nanoporous alumina could be prepared by way of thermal imprinting, dry etching, and anodization. Adoption of reusable polymer soft molds enabled the control of the thickness of the highly ordered porous alumina. It also increased reproducibility of imprinting process and reduced the expense for mold production and pattern generation. As nanoporous alumina templates are mechanically and thermally stable, we expect that the simple and costeffective fabrication through our method would be highly applicable in electronics industry.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.5
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• pp.487-493
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• 1999

To predict the background level of harmonics produced by household appliances, information on the site, capacity, and usage pattern of these loads arenecessary. However, as household appliances are distributed widely and various in type, it is difficult to know these kinds of information accurately. This paper presents a method for estimation of background level of harmonics produced by distributed harmonic sources with readily available data. Large industrial customers are excluded from this study. In this paper, customers are grouped into three classes, i.e. residential, commercial, and industrial. Typical customers for each class are assumed and characteristics of their equipments are modeled. As the proposed method does not require harmonic measurement, it can be employed to forecast voltage total harmonic distribution (VTHD) in the future. An illustrative example is described.

• The Journal of Korean Obstetrics and Gynecology
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• v.34 no.4
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• pp.78-96
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• 2021

Objectives: It is a statistical study to examine the data of CaPSPI (Diagnostic System for Climacteric and Postmenopausal Syndrome Pattern Identification), developed for diagnosis of menopause disorders and to record the status of treatment of it. Methods: From November 1, 2020 to June 19, 2021, 36 cases of data of 33 respondents of the CaPSPI were analyzed. For the use of the basic data of the clinical menopausal disorder, we investigated frequency of menopausal symptoms and the difference between them depending on the period of menopause, and the presentation of usage prescriptions. And the diagnostic results for three kinds' diagnosis [for examination (D1), for treatment (D2), by doctors (D3)] were compared. The diagnostic consistency of D1 and D3 and the statistical significance between DT and disease elements (證素) was investigated. Results: 1. Hot flush was the highest in the symptom survey of the menopause that the subjects complained of, followed by insomnia. There was no significant difference in symptom expression according to menopausal period. 2. The diagnostic consistency of D1 and D2 showed significant diagnostic consistency only in liver depression, and the diagnostic consistency of D1 and D3 showed significant consistency in liver depression and Dual Deficiency of Heart and Spleen. 3. D3' diagnosis and disease elements had statistical significance for cases of P<0.1 was found to be related to the theory of oriental medicine. Conclusions: It is needed to continue to accumulate diagnosis and treatment results through CaPSPI in the future to strengthen the basis for patten identification and treatment of menopause disorders.

• Korean Journal of Metals and Materials
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• v.56 no.12
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• pp.910-914
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• 2018

Since catalyst technology is one of the promising technologies to improve the working performance of next generation energy and electronic devices, many efforts have been made to develop various catalysts with high efficiency at a low cost. However, there are remaining challenges to be resolved in order to use the suggested catalytic materials, such as platinum (Pt), gold (Au), and palladium (Pd), due to their poor cost-effectiveness for device applications. In this study, to overcome these challenges, we suggest a useful method to increase the surface area of a noble metal catalyst material, resulting in a reduction of the total amount of catalyst usage. By employing block copolymer (BCP) self-assembly and nano-transfer printing (n-TP) processes, we successfully fabricated sub-20 nm Pt line and cross-bar patterns. Furthermore, we obtained a highly ordered Pt cross-bar pattern on a Ni thin film and a Pt-embedded Ni thin film, which can be used as hetero hybrid alloy catalyst structure. For a detailed analysis of the hybrid catalytic material, we used scanning electron microscope (SEM), transmission electron microscope (TEM) and energy-dispersive X-ray spectroscopy (EDS), which revealed a well-defined nanoporous Pt nanostructure on the Ni thin film. Based on these results, we expect that the successful hybridization of various catalytic nanostructures can be extended to other material systems and devices in the near future.

• Journal of the Korea Safety Management & Science
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• v.17 no.1
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• pp.149-168
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• 2015

It is expected that the temperature in Pyeongyang will be similar to that ($16.6^{\circ}C$) in Seogwipo in the late 21st century, and most of South Korea will enter the subtropical climate due to climate change. Change in the precipitation pattern like the range of fluctuation caused by climate change will lead to expanded uncertainty in securing reliable water supply, along with a serious impact on demands for living and industrial water due to change in the volume and period of river outflow. As industrial water for production activities is estimated based on the contract quantity, it is difficult to apply rationalization of water usage and incentives in water recycling. Therefore many companies are making efforts in complying with the effluent standard while spending few resources on such rationalization and recycling. This study researched water risk management over 115 Korean companies by 28 questions in 4 categories. Through the research, this study aims to understand water risk management levels and seek response plans.

• Journal of Electrical Engineering and Technology
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• v.8 no.2
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• pp.244-251
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• 2013

This paper presents a study the change of the load profile on the power system by the charging impact of electric vehicles (EVs) in 2020. The impact of charging EVs on the load demand is determined not only by the number of EVs in usage pattern, but also by the number of EVs being charged at once. The charging load is determined on an hourly basis using the number of the EVs based on different scenarios considering battery size, model, the use of vehicles, charging at home or work, and the method of charging, which is either fast or slow. Focusing on the impact of future load profile in Korea with EVs reaching up 10 and 20 percentage, increased power demand by EVs charging is analyzed. Also, this paper analyzes the impact of a time-of-use (TOU) tariff system on the charging of EVs in Korea. The results demonstrate how the penetration of EVs increases the load profile and decreases charging demand by TOU tariff system on the future power system.

• International Journal of Contents
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• v.17 no.1
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• pp.1-10
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• 2021

Visual analytics is an emerging research field that combines the strength of electronic data processing and human intuition-based social background knowledge. This study demonstrates useful visual analytics with Tableau in conjunction with semantic network analysis using examples of sentiment flow and strategic communication strategies via Twitter in a blockchain domain. We comparatively investigated the sentiment flow over time and language usage patterns between companies with a good reputation and firms with a poor reputation. In addition, this study explored the relations between reputation and marketing communication strategies. We found that cryptocurrency firms more actively produced information when there was an increased public demand and increased transactions and when the coins' prices were high. Emotional language strategies on social media did not affect cryptocurrencies' reputations. The pattern in semantic representations of keywords was similar between companies with a good reputation and firms with a poor reputation. However, the reputable firms communicated on a wide range of topics and used more culturally focused strategies, and took more advantages of social media marketing by expanding their outreach to other social media networks. The visual big data analytics provides insights into business intelligence that helps informed policies.

• Journal of Korean Library and Information Science Society
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• v.51 no.2
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• pp.245-272
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• 2020

The purpose of this study is to analyze the current status of space use in university library and draw up considerations for enhancing space utilization based on the analysis results. For this purpose, the utilization rate of each space was analyzed by categorizing the user's space of the university library, and secondly, the preferences of the major user groups were analyzed according to the characteristics of the users' space. For empirical analysis, we collected and refined users' space usage data (98,282 people's data 433,769 cases) accumulated for one year for the central library of "J" National University. Then we analyzed the usage pattern according to space and period(monthly, hourly). In addition, preferences for each major group of users (undergraduates, graduate students and graduates) in the library were analyzed through the library visitors' data (2,426,553 cases) over the same period. The results of this study can be used as preliminary research for the composition and arrangement of users' space in future university libraries.