• Journal of the Korea Society of Computer and Information
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• v.20 no.6
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• pp.127-140
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• 2015

In this study, we aim to analyze the relationship between the centrality in the social network and the sentiment of medial web forum users. In recent, many people use online resources to obtain health and wellness information especially social media resources. In the medial web forum, people give and receive informational supports and emotional supports and this interaction forms the social network. We analyze the social network, derive node characteristics in terms of centrality and compare the centrality index and the sentiment score derived from users' messages. We found that as more people express their emotion, they possess higher central position in the network. Further, people who express positive emotion in their messages have higher central position in the network than people who have negative emotion. This study will help to identify influentials of emotional supports to others and finally to control the depression of Alzheimer's disease patients and their related ones.

• Journal of the Korean Society for Railway
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• v.18 no.4
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• pp.317-324
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• 2015

A super speed maglev is a complicated system integrating electric, electronic, mechanic, civil and construction engineering. So, there must be an integrative system to monitor and manage operation requirements and standard features of each subsystem and the interfaces between each technology. As an indispensable part that can ensure whole system performance, a secure interface for each individual subsystem is an important management item of system engineering. By securing the interface performance of each individual subsystem, system failure can be effectively prevented in advance. Based on system engineering techniques, improvement of security and reliability for a super speed maglev is described in this research.

• Journal of Intelligence and Information Systems
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• v.14 no.3
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• pp.25-39
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• 2008

The objective of this study is to forecast the operational continuous ability using Artificial Neural Networks in battalion defensive operation for the commander decision making support. The forecasting of the combat result is one of the most complex issue in military science. However, it is difficult to formulate a mathematical model to evaluate the combat power of a battalion in defensive operation since there are so many parameters and high temporal and spatial variability among variables. So in this study, we used company combat power level data in Battalion Command in Battle Training as input data and used Feed-Forward Multilayer Perceptrons(MLP) and General Regression Neural Network (GRNN) to evaluate operational continuous ability. The results show 82.62%, 85.48% of forecasting ability in spite of non-linear interactions among variables. We think that GRNN is a suitable technique for real-time commander's decision making and evaluation of the commitment priority of troops in reserve.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.6
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• pp.1447-1453
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• 2014

Wireless Body Area Networks (WBAN), standardized as IEEE 802.15.6, enable digital devices on/around the human body to communicate with one another. WBAN is essentially a person's piconet consisting of a master (mobile) device and several slave devices, which follows his/her mobility pattern, and hence, occasionally collides with another piconet as people meet or pass by. As such, a mechanism to detect collision and avoid interference is needed for intra-piconet communications. In this paper, we focus on this notorious problem of piconet collision and propose Distributed Time Division Piconet Coexistence (DTDPC) using local time offset exchange as a simple, attractive solution. The proposed DTDPC provides different level of services for various applications. Besides our simulation results have shown that the proposed solution outperforms the conventional CSMA protocols.

• IE interfaces
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• v.23 no.4
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• pp.311-318
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• 2010

In the daily multi-reservoir operating problem, monthly storage targets can be used as principal operational guidelines. In this study, we tested the use of a simple back-propagation Artificial Neural Network (ANN) model to derive monthly storage guideline for daily Coordinated Multi-reservoir Operating Model (CoMOM) of the Han-River basin. This approach is based on the belief that the optimum solution of the daily CoMOM has a good performance, and the ANN model trained with the results of daily CoMOM would produce effective monthly operating guidelines. The optimum results of daily CoMOM is used as the training set for the back-propagation ANN model, which is designed to derive monthly reservoir storage targets in the basin. For the input patterns of the ANN model, we adopted the ratios of initial storage of each dam to the storage of Paldang dam, ratios of monthly expected inflow of each dam to the total inflow of the whole basin, ratios of monthly demand at each dam to the total demand of the whole basin, ratio of total storage of the whole basin to the active storage of Paldang dam, and the ratio of total inflow of the whole basin to the active storage of the whole basin. And the output pattern of ANN model is the optimal final storages that are generated by the daily CoMOM. Then, we analyzed the performance of the ANN model by using a real-time simulation procedure for the multi-reservoir system of the Han-river basin, assuming that historical inflows from October 1st, 2004 to June 30th, 2007 (except July, August, September) were occurred. The simulation results showed that by utilizing the monthly storage target provided by the ANN model, we could reduce the spillages, increase hydropower generation, and secure more water at the end of the planning horizon compared to the historical records.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.40
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• pp.26.1-26.10
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• 2018

Background: This study aimed to evaluate the mechanical, biological, and esthetic stability of a zirconium abutment according to evidence-based dentistry. Main text: An electronic search was performed. Domestic studies were found using the keywords "zirconia abutments" and "zirconium abutment" in KMbase, KoreaMed, and the National Assembly Library, and international studies were found using the same keywords in PubMed. All identified studies were divided by evidence level from the viewpoint of the research type utilizing the evidence-based review manual. A total of 102 domestic studies (with Korean language) were found, and 9 of these studies were selected. In these nine studies, 3 had evidence level 3 and 6 had evidence level 4. A total of 97 international studies (with English language) were found, and 19 were selected. Among these 19 studies, 5 had evidence level 2 and 7 had evidence level 3, whereas the remainder had evidence level 4. According to the studies, zirconium abutments are mechanically, biologically, and esthetically stable, but the evidence level of these studies is low, and the follow-up duration is no longer than 5 years. Conclusions: All examined studies verified the mechanical stability of zirconium abutments for a period no longer than 5 years. Therefore, a long-term clinical observation is needed. Zirconium abutments are thought to be biologically stable, but they are not superior to titanium abutments. As the esthetic stability of such abutments had a low evidence level in the studies that examined here, a much higher evidence level is needed.

• Journal of Digital Convergence
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• v.14 no.7
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• pp.373-383
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• 2016

With mobile-epoch and emerging of Fin-tech, Bio-recognition technology utilizing bio-information in secure method has spread. Specially, In order to change convenient payment services and transportation cards, the combination of biometrics and mobile services are being expanded. The basic concept of authentication such as access control, IA&A, OpenID, OAuth 1.0a, SSO, and Biometrics techniques are investigated, and the protocol stack for security API platform, FIDO, SCIM, OAuth 2.0, JSON Identity Suite, Keystone of OpenStack, Cloud-based SSO, and AIM Agent are described detailed in aspect of application of AIM. The authentication technology in domestic and foreign will accelerate technology development and research of standardization centered in the federated FIDO Universal Authentication Framework(UAF) and Universal 2 Factor Framework(U2F). To accommodate the changing needs of the social computing paradigm recently in this paper, the trends of various authentication technology, and design and function of AIM framework was defined.

• Journal of Digital Convergence
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• v.18 no.7
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• pp.31-36
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• 2020

In recent years, increasing the variety of disasters and accidents that accompany large-scale damage. Disasters are accidents with uncertainty and have a direct impact on people's lives, safety and property protection. Therefore, it is necessary to establish and operate safety management systems such as prevention, response, and recovery for various disasters. Therefore, in this paper, a real-time disaster safety management solution in a smart environment was designed to systematically respond to disaster accidents. To this end, 1: 1 or 1: N situation propagation was performed to the situation room, related organizations, and experts through smart devices. Through this, the solution was configured to respond quickly and appropriately through multi-party information sharing and communication. In other words, we designed a solution that applied functions such as real-time and multi-party HD video transmission, mobile-type report management, voice / text situation propagation, location information sharing, recording and history management, and security.

• Nuclear Engineering and Technology
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• v.52 no.10
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• pp.2250-2261
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• 2020

Accurate localization of radioactive materials is crucial in homeland security and radiological emergencies. Coded-aperture gamma camera is an interesting solution for such applications and can be developed into portable real-time imaging devices. However, traditional reconstruction methods cannot effectively deal with signal-independent noise, thereby hindering low-noise real-time imaging. In this study, a novel reconstruction method with excellent noise-suppression capability based on a multi-layer perceptron (MLP) is proposed. A coded-aperture gamma camera based on pixel detector and coded-aperture mask was constructed, and the process of radioactive source imaging was simulated. Results showed that the MLP method performs better in noise suppression than the traditional correlation analysis method. When the Co-57 source with an activity of 1 MBq was at 289 different positions within the field of view which correspond to 289 different pixels in the reconstructed image, the average contrast-to-noise ratio (CNR) obtained by the MLP method was 21.82, whereas that obtained by the correlation analysis method was 5.85. The variance in CNR of the MLP method is larger than that of correlation analysis, which means the MLP method has some instability in certain conditions.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.7
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• pp.567-577
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• 2012

This study examines the spatial compositions of children's reading rooms, furniture characteristics, and users' satisfaction levels for the furniture in public libraries. Field measurements and surveys were performed in 5 public libraries. Results imply that the spatial compositions of reading rooms in libraries were classified into three categories according to the locations of bookshelves and reading space. Management areas should not be located at the edge of reading rooms but be located at the center of reading rooms to avoid clerks' narrow viewing angle toward young kids and to ensure security for the kids. The evaluation for bookshelves according to evaluation checklists was acceptable, but users were not always satisfied with the bookshelves due to the inappropriate positions of books in shelves. The evaluation for desks was generally acceptable according to the checklists and users were satisfied with them. In general, the desk with higher scores by the checklist provided better satisfaction to users. However, the score by checklist for chair and user satisfaction were not always similar each other. Convenience areas in reading rooms were not enough compared to bookshelf, reading and management area. Computer tables that were designed in a way that users sit down and use the computers were highly preferred.