• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.9-14
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• 2002

We propose a new algorithm for blind source separation (BSS), in which frequency-domain independent component analysis (FDICA) and time-domain ICA (TDICA) are combined to achieve a superior source-separation performance under reverberant conditions. Generally speaking, conventional TDICA fails to separate source signals under heavily reverberant conditions because of the low convergence in the iterative learning of the inverse of the mixing system. On the other hand, the separation performance of conventional FDICA also degrades significantly because the independence assumption of narrow-band signals collapses when the number of subbands increases. In the proposed method, the separated signals of FDICA are regarded as the input signals for TDICA, and we can remove the residual crosstalk components of FDICA by using TDICA. The experimental results obtained under the reverberant condition reveal that the separation performance of the proposed method is superior to that of conventional ICA-based BSS methods.

• Journal of Magnetics
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• v.22 no.1
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• pp.14-22
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• 2017

The NMR's probe consists of the static magnetic field generator (magnetic source) and the RF coil. It is very strict for the homogeneity of the static magnetic field intensity of the magnetic source, so the cost of the magnetic source is more expensive in the entire nuclear magnetic resonance instrument. The magnetic source generally consists of electromagnet, permanent magnet and superconducting magnet. The permanent magnet basically needs not to spend on operation and maintenance and its cost of manufacture is much cheaper than the superconducting magnet. Therefore, the permanent magnet may be the only choice for the static magnetic field device if we want to use the magnetic resonance instrument as an analyzer for production by reducing price. A new probe magnet was developed on the basis of the permanent magnet ring in this paper to provide a technological way for reducing the manufacturing cost, weight and volume of the existing nuclear magnetic resonance instrument (including MRI) probe.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.26 no.2
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• pp.317-320
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• 2022

This paper studies real-time error in the context of monitoring a symmetric binary information source over a delay system. To obtain the average real-time error, the delay system is modeled and analyzed as a discrete time Markov chain with a finite state space. Numerical analysis is performed on various system parameters such as state transition probabilities of information source, transmission times, and transmission frequencies. Given state transition probabilities and transmission times, we investigate the relationship between the transmission frequency and the average real-time error. The results can be used to investigate the relationship between real-time errors and age of information.

• Journal of Information Processing Systems
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• v.17 no.3
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• pp.537-555
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• 2021

Many researchers have carried out studies related to programming languages since the beginning of computer science. Besides programming with traditional programming languages (i.e., procedural, object-oriented, functional programming language, etc.), a new paradigm of programming is being carried out. It is programming with natural language. By programming with natural language, we expect that it will free our expressiveness in contrast to programming languages which have strong constraints in syntax. This paper surveys the approaches that generate source code automatically from a natural language description. We also categorize the approaches by their forms of input and output. Finally, we analyze the current trend of approaches and suggest the future direction of this research domain to improve automatic code generation with natural language. From the analysis, we state that researchers should work on customizing language models in the domain of source code and explore better representations of source code such as embedding techniques and pre-trained models which have been proved to work well on natural language processing tasks.

• The Journal of Information Systems
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• v.20 no.4
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• pp.1-22
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• 2011

This study addressed trust to collective intelligence for explaining the affecting factors to the intention to use of collective intelligence by dividing the object of trust into a Web site and an information source group. We explored the factors affecting user's continuance intention toward collective intelligence in the view off trust building. We made a well-structured survey of our proposed model and gained 205 cases. We analyzed the proposed research model empirically using partial least square method. The findings are summarized as follows. First, all key factors (relevance, timeless, completeness, understandability) composing of collective intelligence quality have a positive and significant impact on confirmation. Second, confirmation has a significant impact on trust toward a Web site, as well as toward an information source group. The last is that trust toward a Web site influences on continuance intention, whereas trust toward an information source group doesn't.

• 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 the Korean Society of Costume
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• v.51 no.7
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• pp.123-134
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• 2001

The purpose of this study to compare the purchasing behaviour of men's business suits, among custom suits, system order, and ready-made suits, centering around the choice of information source, risk perception and benefits sought. The survey of this study was collected from 450 adult male in Seoul. The data was analyzed by factor analysis and ANOVA. The result of this study were as follows : 1. Custom suits, system order, and ready-made suits consumers have a significant difference in the choice of information source. The consumer attaching most importance to the impersonal information source is the system order users, custom suits users, and ready-made suits users respectively. However there was no significant difference in the personal source among 3 different purchasing behaviour of men's suits. 2. For the risk perception, 1) the group who perceived the highest in economic risk is the system order users, followed by custom suits users, and ready-made suits users. 2) the group who perceived performance risk as being the highest concern is the ready-made suits consumers, followed by system order user, and custom suits user. 3) the group who perceived the socio-psychological risk as the highest is the ready-made suits consumers, and followed by custom suits user and system order users. 4) there is no difference among the three groups with respect to the fashionability loss risk. 5) the group of the highest perceiving the useful loss risk is the ready-made suits consumers, and the next is system order users, custom suits users. 6) the group of the highest perceiving the time and convenience loss risk is ready-made suits users, and the next is system order users, custom suits users. 3. For the benefit sought, the group of the highest perceiving the aesthetics is custom suits consumers, and the next is system order users, ready-made suits users.

• Journal of Information Processing Systems
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• v.13 no.3
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• pp.630-642
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• 2017

In this paper, we propose the opportunistic non-orthogonal multiple access (NOMA)-based cooperative relaying system (CRS) with channel state information (CSI) available at the source, where CSI for the source-to-destination and source-to-relay links is used for opportunistic transmission. Using the CSI, for opportunistic transmission, the source instantaneously chooses between the direct transmission and the cooperative NOMA transmission. We provide an asymptotic expression for the average achievable rate of the opportunistic NOMA-based CRS under Rayleigh fading channels. We verify the asymptotic analysis through Monte Carlo simulations, and compare the average achievable rates of the opportunistic NOMA-based CRS and the conventional one for various channel powers and power allocation coefficients used for NOMA.

• Journal of KIBIM
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• v.5 no.2
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• pp.19-25
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• 2015

The purpose of this study is to design simple BIM query language for visualizing BIM information as the viewpoint of use-cases by using open source viewer cost-effectively. recently, the studies related to the facility management using BIM are being researched world-widely. In this studies, it's important to develop the BIM query to obtain the needed data from BIM database. To implement it, the trends in related studies were reviewed and the open source-based BIM viewer architecture was analyzed. And then the architecture considering the simple BIM Query Language (sBQL) was designed to represent the geometry and property of the BIM database. Lastly, the system by using the proposed sBQL grammar was developed.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.11
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• pp.1814-1824
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• 2008

The purpose of this study was to investigate the information search behavior in functional sportswear purchasing by clothing and sports concern variables. Functional sportswear means sportswear made of functional clothing materials. The information search behavior in this study included information sources, information seeking attributes, information search differences between when consumers buy functional sportswear and when they purchase nonfunctional sportswear, and information characteristics. For this purpose, 500 questionnaires had been distributed to university students and 409 of which were used in the study. For data analysis, frequency, reliability analysis, factor analysis, and t-test were used. The results were as follows: first, the friends showed to be the most effective information source of functional clothing materials sportswear and internet revealed to be the information source that made the most frequent use of. The experts appeared to be the most reliable information source. Second, the more the students were concerned about clothing and sports, the more important they considered information seeking attributes. Third, in the aspects of information search differences between when consumers bought functional sportswear and when they purchased nonfunctional sportswear, only sports concern variables showed to be significant. The last, regardless of clothing and sports concern variables, it was found that customers considered all the information characteristics important.