• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.7C
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• pp.665-671
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• 2006

In this paper, we propose and observe a system that adopts Independent-MCS (Modulation and Coding Scheme) level for each layer in the combined AMC-V-BLAST (Adaptive Modulation and Coding-Vertical-Bell-lab Layered Space-Time) system. Also, comparing with the combined system using Common-MCS level, we observe throughput performance improvement. As a result of simulation, Independent-MCS level case adapts modulation and coding scheme for maximum throughput to each channel condition in separate layer, resulting in improved throughput compared to Common-MCS level case. Especially, the results show that the combined AMC-V-BLAST system with Independent-MCS level achieves a gain of 700kbps in $7dB{\sim}9dB$ SNR (Signal-to-Noise Ratio) range.

• Journal of applied mathematics & informatics
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• v.27 no.3_4
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• pp.621-638
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• 2009

The linear system Ax = b will have (i) no solution, (ii) only one non-trivial (trivial) solution, or (iii) infinity of solutions. Our focus will be on cases (ii) and (iii). The mathematical models of many real-world problems give rise to (a) ill-conditioned linear systems, (b) singular linear systems (A is singular with all its linearly independent rows are sufficiently linearly independent), or (c) ill-conditioned singular linear systems (A is singular with some or all of its strictly linearly independent rows are near-linearly dependent). This article highlights the scope and need of a randomized algorithm for ill-conditioned/singular systems when a reasonably narrow domain of a solution vector is specified. Further, it stresses that with the increasing computing power, the importance of randomized algorithms is also increasing. It also points out that, for many optimization linear/nonlinear problems, randomized algorithms are increasingly dominating the deterministic approaches and, for some problems such as the traveling salesman problem, randomized algorithms are the only alternatives.

• The Journal of the Acoustical Society of Korea
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• v.21 no.4E
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• pp.156-163
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• 2002

We apply independent component analysis (ICA) for extracting an optimal basis to the problem of finding efficient features for representing speech signals of a given speaker The speech segments are assumed to be generated by a linear combination of the basis functions, thus the distribution of speech segments of a speaker is modeled by adapting the basis functions so that each source component is statistically independent. The learned basis functions are oriented and localized in both space and frequency, bearing a resemblance to Gabor wavelets. These features are speaker dependent characteristics and to assess their efficiency we performed speaker identification experiments and compared our results with the conventional Fourier-basis. Our results show that the proposed method is more efficient than the conventional Fourier-based features in that they can obtain a higher speaker identification rate.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2004.04a
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• pp.515-518
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• 2004

This paper presents a method that improves the performance of the personal voice dialling system in which speaker Independent phoneme HMM's are used. Since the speaker independent phoneme HMM based voice dialing system uses only the phone transcription of the input sentence, the storage space could be reduced greatly. However, the performance of the system is worse than that of the system which uses the speaker dependent models due to the phone recognition errors generated when the speaker Independent models are used. In order to solve this problem, a new method that jointly estimates transformation vectors for the speaker adaptation and transcriptions from training utterances is presented. The biases and transcriptions are estimated iteratively from the training data of each user with maximum likelihood approach to the stochastic matching using speaker-independent phone models. Experimental result shows that the proposed method is superior to the conventional method which used transcriptions only.

• Journal of Korea Multimedia Society
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• v.21 no.9
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• pp.1119-1130
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• 2018

Writing letters or patterns on a virtual space by moving a person's gaze is called "eye writing," which is a promising tool for various human-computer interface applications. This paper investigates the use of conventional eye writing recognition algorithms for the purpose of user-independent recognition of eye-written characters. Two algorithms are presented to build the user-independent system: eye-written region extraction using wavelet coefficients and template generation. The experimental results of the proposed system demonstrated that with dynamic positional warping, an F1 score of 79.61% was achieved for 12 eye-written patterns, thereby indicating the possibility of user-independent use of eye writing.

• Journal of Power Electronics
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• v.13 no.1
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• pp.77-85
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• 2013

This paper proposes a new dead time compensation method of independent six-phase permanent magnet synchronous motors (IS-PMSM). The current of the independent phase machines contains odd-numbered harmonics because of the dead time and the nonlinear characteristics of the switching devices. By using the d-q-n three-dimensional vector analysis, these harmonics can be extracted at the n-axis current. Thus, the current distortion can be compensated by controlling the n-axis current of the IS-PMSM to zero. The proposed method is simple and can be easily implemented without additional hardware setup. The validity of the proposed compensation method is verified with simulations and several experiments.

• The Journal of the Acoustical Society of Korea
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• v.21 no.4
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• pp.156-156
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• 2002

We apply independent component analysis (ICA) for extracting an optimal basis to the problem of finding efficient features for representing speech signals of a given speaker The speech segments are assumed to be generated by a linear combination of the basis functions, thus the distribution of speech segments of a speaker is modeled by adapting the basis functions so that each source component is statistically independent. The learned basis functions are oriented and localized in both space and frequency, bearing a resemblance to Gabor wavelets. These features are speaker dependent characteristics and to assess their efficiency we performed speaker identification experiments and compared our results with the conventional Fourier-basis. Our results show that the proposed method is more efficient than the conventional Fourier-based features in that they can obtain a higher speaker identification rate.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.22 no.1
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• pp.13-31
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• 2019

Green spaces are recognised for the benefits. They bring to the quality of people's lives. However, since the 1980s there has been a general increase in poorly-managed green spaces. In an attempt to address this issue, green space policy has changed its focus on green space management through the gradual introduction of green space evaluation tools, such as the Green Flag Award (GFA). The GFA, as an established green space evaluation tool in the UK, reflects a shift in policy drivers of green spaces management. However, there is a lack of research investigating the contextualisation between a wide range of policy contexts and such green space evaluation tools (the GFA in this study). The aims of this study are therefore to explore the development of green space evaluation since the late 1990s, with respect to the growth of the GFA and its impact on other evaluation tools across the UK and several countries. To address the aims, this study employs in-depth literature reviews on UK green space policy mainly conducted by government. In addition, case studies are presented, focusing on the GFA and independent green space evaluation tools intrinsically derived from the GFA in the UK's cities and Nordic countries. Results show that based on the awareness of the severity of declining standards of green spaces, newly emerging policy arrangements have been adopted to address negative issues, which affect the standard of green spaces such as the transfer of responsibility for green space management, the implementation of Compulsory Competitive Tendering and ongoing budget cuts. Significantly, the GFA's indicators reflect the emerging changes of economic and social contexts associated with green spaces management where, in particular, the prospect of continuous budget cuts, which encourages communities to become involved in green space management. The GFA has widely contributed to leading such UK's cities and other countries to be able to create their independent green space evaluation tools in different approaches based on stakeholders' (mainly community) involvement in the decision-making process of green space evaluation. In conclusion, this study implies that successful green space evaluation tools do embody the value of green spaces and address drivers of emerging green space management with correspondence to the context of policy arrangements. Importantly, stakeholders have an opportunity to be involved in a partnership in the decision-making process through some green space evaluation tools. It is hoped that for well-managed green spaces this study will contribute valuable knowledge to our existing understanding of green space management in an era of austerity.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.22 no.1
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• pp.170-176
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• 1998

In this paper, the column space and null space of the Jacobian matrix were obtained by using the pseudo-inverse method and projection matrix. The equations of motion of the system were replaced by independent acceleration components using the null space matrix. The proposed method has the following advantages. (1) It is simple to derive the null space. (2) The efficiency is improved by getting rid of constrained force terms. (3) Neither null space updating nor coordinate partitioning method is required. The suggested algorithm is applied to a three-dimensional vehicle model to show the efficiency.

• Korean Institute of Interior Design Journal
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• no.7
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• pp.45-49
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• 1996

The purpose for this study shows general planning direction about showroom which can enhance sales promotion, and corporate image and through buyer negotiation increasing export. We can divide showroom as promotional showroom and institutional showroom as a whole. The results of this research can be summarized as follows : There is no uniformed design plan of display for the P.R of showroom. And they need independent business space. But, there is no attractive factors to fascinate their consumer and thus there is no sufficient service facility, Also, some more effective planning is needed to support their supervisors. I wish to suggest some planning direction on the basis of research problems : We need to divide four space- that is entrance space, display space management space, service space-to allocative effectively space for the purpose of charging product. P.R. We should set up uniformed design policy which can contribute P.R.-that is corporate color, unform . logotype, sign, pamphlet etc.