• KSII Transactions on Internet and Information Systems (TIIS)
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• v.7 no.6
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• pp.1418-1432
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• 2013

This paper studies the problem of secure information exchange between two sources via multiple relays in the presence of an eavesdropper. To this end, we propose a relay beamforming scheme, i.e., relay beamforming with artificial noise (RBwA), where the relay beamforming vector and the artificial noise vector are jointly designed to maintain the received signal-to-interference-ratio (SINR) at the two sources over a predefined Quality of Service (QoS) threshold while limiting the received SINR at the eavesdropper under a predefined secure threshold. For comparison, the relay beamforming without artificial noise (RBoA) is also considered. We formulate two optimization problems for the two schemes, where our goal is to seek the optimal beamforming vector to minimize the total power consumed by relay nodes such that the secrecy of the information exchange between the two sources can be protected. Since both optimization problems are nonconvex, we solve them by semidefinite program (SDP) relaxation theory. Simulation results show that, via beamforming design, physical layer secrecy of two-way relay networks can be greatly improved and our proposed RBwA outperforms the RBoA in terms of both low power consumption and low infeasibility rate.

• Journal of Preventive Medicine and Public Health
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• v.46 no.2
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• pp.82-88
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• 2013

Objectives: Unprotected leisure time exposure to ultraviolet radiation from the sun or artificial tanning beds is the most important environmental risk factor for melanoma, a malignant skin cancer with increasing incidences over the past decades. The aim of the present study was to assess the impact of skin health information provided by several sources and different publishing issues on knowledge, risk perception, and sun protective behavior of sunbathers. Methods: A cross-sectional questionnaire survey was conducted among Austrian residents (n=563) spending leisure time outdoors in August 2010. Results: Print media, television, and family were perceived as the most relevant sources of information on skin health, whereas the source physician was only ranked as fourth important source. Compared to other sources, information provided by doctors positively influenced participants' knowledge on skin risk and sun protective behavior resulting in higher scores in the knowledge test (p=0.009), higher risk perception (p<0.001), and more sun protection (p<0.001). Regarding gender differences, internet was more often used by males as health information source, whereas females were more familiar with printed information material in general. Conclusions: The results of this survey put emphasis on the demand for information provided by medical professionals in order to attain effective, long-lasting promotion of photoprotective habits.

• Journal of the Korean Institute of Navigation
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• v.24 no.1
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• pp.73-84
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• 2000

Shipping industry continues to face dramatic changes in its environment ranging from development in containerization, computerization and telecommunications to the emergence of global marketplace. Perhaps the most significant trend - representing both a threat and opportunity - is the increasingly competitive nature of shipping service market. In order for the shipping companies to cope with those improvements and challenges, they should analyze and clarify customer's DM(decision making) process for the purchase of container shipping service. The major research findings from the study were found as follows; 1) The degree of shipper's involvement in purchasing shipping services was found to be a discriminating variable affecting the information sources consisting of personal and non-personal information sources. 2) The positive relationship was found between the experiences on shipping services and non-personal information sources. 3) It was observed that as people had more experience searching for information, the more in depth their searches became. 4) There existed a positive relationship between knowledges on shipping services and information search. 5) According to the SEM analysis, the shipper's information search on shipping services was also found to have a great influence on the shipper's purchasing behavior. The shipper's search was resulted in positive customer satisfaction.

• Proceedings of the IEEK Conference
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• 2000.07b
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• pp.1092-1095
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• 2000

Computer graphics(CG) is one of the most useful tools by which we can easily understand visible/invisible natural phenomena. Namely, phenomena in the universe is attractive one because of its beauty and invisibility on the earth. For gravitational tensing phenomena, a ray tracing algorithm is proposed based on a lens-plane. In the method, position of gravitational sources is restricted. In this paper an improved visualization method is proposed, which can represent more complex situation than the previous method.

• Journal of Energy Engineering
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• v.23 no.3
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• pp.13-16
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• 2014

We have surveyed on significant progress in recent developments of accelerator-based pulsed X-ray sources has offered the opportunity for time-resolved studies on fast structure dynamics on the nanometer scale. The required and currently available techniques for time resolved X-ray diffraction measurements using the third-generation synchrotron radiation sources are summarized. Ultrafast X-ray experimental techniques are discussed for femtosecond studies at future synchrotron radiation sources.

• Korean Journal of Human Ecology
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• v.14 no.1
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• pp.167-178
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• 2005

The purpose of this study is to research male consumers' shopping behavior according to their fashion consciousness. For the purpose, the data collected were analyzed by factor analysis, one-way ANOVA, Duncan's multiple range test X2-test, and Pearson's correlation. The results of the study are as follows: 1. Male consumers' fashion consciousness were classified into 4 groups-Impulse Buying Consciousness Group, Brand Consciousness Group, Style Consciousness Group, and Fashion Indifference Group-by the following 6 factors: Impulse Buying Consciousness, Brand Consciousness, Style Consciousness, Trend Consciousness, Price Consciousness, Consumption Expenditure Consciousness. 2. There were significant differences existed among each group according to clothing purchase behavior, shopping orientation, and use of information sources. 3. There were a relationship among male consumers' fashion consciousness, their use of information sources, and their shopping behavior including clothing shopping orientation.

• Journal of information and communication convergence engineering
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• v.18 no.1
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• pp.22-27
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• 2020

Content centric networking (CCN) is regarded as promising internet architecture because it can provide network efficiency in terms of bandwidth consumption by separating contents from a specific network location and decrease network congestion events. However, the application of a CCN does not widely consider the side effects of mobile devices, particularly mobile content sources. For content source mobility, a full routing update is required. Therefore, in this study, a route optimization scheme is proposed for mobile content sources in a CCN environment to provide low communication overhead, short download time, and low resource consumption. The proposed scheme establishes a direct path between content requesters and a mobile content source for the exchange of interest and data packets using interest-piggybacked data packets. Based on the inherent CCN naming characteristics, the content source does not know the name prefix of the content consumer, and thus the proposed optimized CCN scheme utilizes the content router in the home domain of the content source.

• Journal of Information Science Theory and Practice
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• v.6 no.3
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• pp.6-15
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• 2018

With the increasing demand for intelligent services, knowledge graph technologies have attracted much attention. Various application-specific knowledge bases have been developed in industry and academia. In particular, open knowledge bases play an important role for constructing a new knowledge base by serving as a reference data source. However, identifying the same entities among heterogeneous knowledge sources is not trivial. This study focuses on extracting and determining exact and precise entities, which is essential for merging and fusing various knowledge sources. To achieve this, several algorithms for extracting the same entities are proposed and then their performance is evaluated using real-world knowledge sources.

• Journal of the Korean Home Economics Association
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• v.39 no.12
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• pp.129-140
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• 2001

The effects of material monitoring and information sources of maternal knowledge on externalizing and internalizing behaviors of adolescents were examined with a sample of 323 ninth-grade middle school students(163 boys and 160 girls) and their mothers. Data were collected using questionnaires regarding maternal monitoring, information sources of maternal knowledge, and externalizing and internalizing behaviors of adolescents. The major findings were that 1) unemployed mothers showed more monitoring than employed mothers; 2) mothers perceived that girls showed more self-disclosure and were more controlled by them than boys; 3) girls showed more internalizing behavior than boys; 4) the more adolescents were monitored by their mothers, the less internalizing behavior they showed; 5) the more maternal solicitation was used, the more externalizing behavior girls showed; 6) adolescents showed the least externalizing behavior when maternal monitoring was highly perceived by both mothers and adolescents. And perception of maternal monitoring by adolescents themselves plays an important role in showing less externalizing behavior.

• Journal of the Korea Convergence Society
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• v.2 no.4
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• pp.21-27
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• 2011

Recently, new distributed power sources such as photovoltaic, wind power, fuel cell systems etc. are energetically interconnected and operated in the distribution feeders, as one of the national projects for alternative energy. When new power sources are considered to be interconnected to distribution systems, bi-directional power flow and interconnection conditions of new power sources may cause several power quality problems like voltage sag, voltage swell, harmonics, since new power sources can change typical characteristics of distribution systems. Under these situations, this paper deals with the analysis the power quality problems at primary and secondary feeders in distribution systems, when new power sources like photovoltaic (PV) systems are interconnected, by using the test devices for PV systems based on the LabVIEW S/W. This paper presents the test device which is consisted with model distribution system and model PV systems. By performing the simulation for power quality operation characteristic based on the test facilities, this paper presents the optimal countermeasures for power quality.