• Journal of the Korea Convergence Society
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• v.8 no.11
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• pp.103-108
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• 2017

In the ubiquitous environment, there has been a problem of transmitting data from various sensors at a long distance. Especially, in the process of integrating data arriving at different locations, data having different property values of data or having some loss in data had to be processed. This paper present a method to analyze such data. The core of this method is to define an objective function suitable for the problem and to develop an algorithm that can optimize this objective function. The objective function is used by modifying the OCS function. MFA (Mean Field Annealing), which was able to process only binary data, is extended to be applicable to fields with continuous values. It is called CMFA and used as an optimization algorithm.

• Journal of Mechanical Science and Technology
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• v.14 no.10
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• pp.1051-1060
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• 2000

Linear cyclic systems (LCS's) are a class of systems whose dynamic behavior changes cyclically. Such cyclic behavior is ubiquitous in systems with fundamentally repetitive motions (e. g. all rotating machinery). Yet, the knowledge of the noise and vibration transmission paths in LCS's is quite limited due to the time-varying nature of their dynamics. The first part of this two-part paper derives a generic expression that describes how the noise and/or vibration are transmitted between two (or multiple) locations in the LCS's. An analysis via the Fourier series and Fourier transform (FT) plays a major role in deriving this expression that turns out to be transfer function dependent upon the cycle position of the system. The cyclic nature of the LCS' transfer functions is shown to generate a series of amplitude modulated input signals whose carrier frequencies are harmonic multiples of the LCS' fundamental frequency. Applicability of signal processing techniques used in the linear time-invariant systems (LTIS's to the general LCSs is also discussed. Then, a criterion is proposed to determine how well a LCS can be approximated as a LTIS. In Part II, experimental validation of the analyses carried out in Part I is provided.

• Korean Institute of Interior Design Journal
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• v.19 no.3
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• pp.251-259
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• 2010

The purpose of this study is to show the characteristics of integrated welfare center space by applying Context-Awareness technology in order to provide user-friendly services for efficient use of integrated welfare centers as more and more people are interested in using welfare integrated welfare centers which have increasingly been supplied. For this study, we propose the spaces which provide users of integrated welfare centers with proper services by applying Context-Awareness after reviewing the theory of Context-Awareness through literature study as well as case analysis and choosing the reasonable Context-Awareness technology for integrated welfare centers. As it is possible to efficiently provide users with safety service, information service and convenient service by the analysis of space, users' movement in lobby where Context-Awareness is applied and the lobbies of integrated welfare centers in Munsan area, Paju-si out of domestic cases about integrated welfare centers, the different type of spaces from the existing one is expected.

• Journal of KIISE:Computer Systems and Theory
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• v.35 no.7
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• pp.332-339
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• 2008

Radio Frequency Identification (RFID) technology is an important part of infrastructures in ubiquitous computing. Although all products using tags is a target of these services, these products also are a target of attacking on user privacy and services using authentication problem between user and merchant, unfortunately. Presently, it is very important about security mechanism of RFID system and in this paper, we analyze the security protocol among many kinds of mechanisms to solve privacy and authentication problem using formal verification and propose a modified novel protocol. In addition, the possibility of practical implementation for proposed protocol will be discussed.

• Journal of Korea Society of Digital Industry and Information Management
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• v.8 no.4
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• pp.273-288
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• 2012

In recent years, smartphone is the most widely used ubiquitous functionality. People do not want to just call other people any more by using a cellular phone; they want to connect to the Internet and use various applications. Hence, cellular phones need to become smart. A smartphone has an operating system and many applications. Specifically the goals of this research are; (1) to suggest theory framework of acceptance about smartphone based on TAM, (2) to examine relationships between exogenous variables. The research model and hypotheses were developed based on the theories of technology acceptance model. Questionnaire was used to collect data. The analysis of this study is designed as individual level to examine the causal relationship among variables. The the reliability and validity of data was tested by explanatory factor analysis, Cronbach's alpha coefficient, confirmatory factor analysis, and correlation analysis. Also, the structural equation model(SEM) analysis was performed to test the usefulness of the model. The analysis results revealed that social norms and individual innovation are major influential variables on the perceived usefulness of smartphone. Also, social norms are influential variables on the perceived enjoyment of smartphone.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.2
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• pp.649-663
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• 2012

We propose a percolation based M2M networking architecture and its data transmission method. The proposed network architecture can be server-free and router-free, which allows us to operate routing efficiently with percolations based on six degrees of separation theory in small world network modeling. The data transmission can be divided into two phases: routing and data transmission phases. In the routing phase, probe packets will be transmitted and forwarded in the network thus multiple paths are selected and performed based on the constriction of the maximum hop number. In the second phase, the information will be encoded, say, with the fountain codes, and transmitted using the paths generated in the first phase. In such a way, an efficient routing and data transmission mechanism can be built, which allow us to construct a low-cost, flexible and ubiquitous network. Such a networking architecture and data transmission can be used in many M2M communications, such as the stub network of internet of things, and deep space networking, and so on.

• Journal of KIISE:Computing Practices and Letters
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• v.15 no.2
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• pp.89-97
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• 2009

Embedded systems widely used in ubiquitous environments usually employ an event-driven programming model instead of thread-based programming model in order to create a more robust system that uses less memory. However, as the software for embedded systems becomes more complex, it becomes hard to program as a single event handler using the event-driven programming model. This paper discusses the implementation of non-preemptive real-time scheduling theory for the design of embedded systems. To this end, we present an efficient schedulability test method for a given non-preemptive task set using a sufficient condition. This paper also shows that the notion of sub-tasks in embedded systems can overcome the problem of low utilization that is a main drawback of non-preemptive scheduling.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.2
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• pp.32.1-32.1
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• 2018

The galactic warp is almost ubiquitous among disk galaxies and suspected to be an imprint of recent interactions with other galaxies. The detailed evolutionary course, however, is still uncertain due to the lack of observational evidence. To address this issue, we construct a new extensive catalog of 412 conspicuously warped disks at z = 0.01 ~ 0.05, based on SDSS DR7. We classify the warp morphology through a visual inspection from the Zooniverse Project and our new automated scheme for the warp measurement. We find an interesting color difference between S-and U-shaped warps. The U-type warp galaxies exhibits considerable color offset towards blue compared to both the S-type warps and the control sample of un-warped galaxies. The effect is even more pronounced for galaxies (a) with the greater warp amplitude and (b) with lower luminosity. This is the first piece of observational evidence that the S- and U-shaped warps are on different evolutionary phases in terms of not only dynamics but stellar populations as well. We discuss the implications in the context of the warp evolution theory.

• Journal of Korea Entertainment Industry Association
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• v.14 no.3
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• pp.149-162
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• 2020

This paper applied components of experience-based communication in terms of experience theory of Burnd H. Schmitt and context-based communication in the messenger platform environment through the scenario-based survey method, in order to study the influence of individual experiences, shared experiences, ubiquitous connectivity, and contextual usefulness on the perceived value and use intention of chatbot. Through this, the study is to provide companies in various service industries with practical approaches to further promote the use of chatbot. The implications of this study are as follows. First, as most chatbots still do not exceed the human planning level of designing them, it is necessary to consider how to design individual experience elements functionally according to the customer's intention to speak when developing the chatbot. Second, the chatbot should be designed not only from the perspective of completing specific tasks at any real time in anywhere, but also from the overall perspective of enhancing the quality of interaction, including the situation to which the customer belongs. Third, since the chatbot is likely to be anthropomorphized by users, it is important to be cautious about determining the chatbot's 'persona' and 'tone and manner' when developing the chatbot. Customer satisfaction is the most important criterion for the success of chatbot development. In other words, the quality of planning and data rather than the quality of artificial intelligence algorithms determines the utilization of chatbot. This is why companies are trying to make interactions with chatbot as close as possible to human interactions.

• Journal of Korean Home Economics Education Association
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• v.28 no.3
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• pp.17-32
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• 2016

This exploratory study which applied environmental scanning method to analyse a change in a future society tried to diagnose a reaction ability of our education system for the change in the future society. In addition, the study tried to explore an adequate direction for Home Economics Subject to be an mandatory subject continuously toward the change in the future society. Main changes in the future society can be expected as 1) demographic change due to low birth rate and aging society, 2) an increasing threat of a human living environment due to unexpectable natural disasters and accidents, 3) a radical progress into a ubiquitous computing environment led by AI, 4) an advent of a borderless economic society and a change for jobs, 5) a change in North Korea, and so on. Our education system which mostly concentrates on education to develop constructive intelligence by halving the society and schooling as yet, however, is diagnosed as it has a paradox that can not understand an emotional competency as a target for studying. Home Economics Subject is worth as the subject that can exactly complement a blind spot of our education system which can not respond to the future society adequately. This is because Home Economics Subject has had a characteristic as a 'Subject of Life' traditionally that has dealt with an overall 'life' of human beings, and the characteristic is favorable to develop human practical intelligence. Thus, because the 'life' is the main point of Home Economics Subject, it has the characteristic as a 'Subject of Happiness' which is the most effective method to develop a tendency to appreciate, a sense of empathy, and lots of pro-social behaviors that are important capacities to seek for happiness. As Alderfer's ERG Theory is to understand human beings' behavior based on the satisfactory of human beings' hierarchical desires, it is suggested as an adequate frame for the theory to restructure the characteristic of Home Economics Subject which develops the 'capacity to seek for happiness' by focusing the 'life', into core concept and core capacity of curriculum. A follow-up study should make a connection between ERG Theory and core concept and core capacity of curriculum to explore how the theory can be reflected on Home Economics curriculum.