• 제목/요약/키워드: independent space

검색결과 1,016건 처리시간 0.024초

MCS 레벨 선택 방식에 따른 AMC-MIMO 결합 시스템의 성능 비교 (Perfonnance Analysis of the Combined AMC-MIMO Systems with MCS Level Selection Method)

  • 황인태;강민구
    • 한국통신학회논문지
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    • 제31권7C호
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    • pp.665-671
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    • 2006
  • 본 논문에서는 AMC-V-BLAST(Adaptive Modulation and Coding-Vertical-Bell-lab Layered Space-Time) 결합 시스템에 각 레이어 별로 독립적인 MCS(Modulation and Coding Scheme) 레벨을 적용한 경우의 시스템 구조를 제시후 성능을 관찰한다. 그리고 공통적인 MCS 레벨이 적용된 결합 시스템의 성능에 비하여 어느정도의 전송률 향상이 있는가를 살펴본다. 실험결과, 독립적인 MCS 레벨이 적용된 경우가 레이어 별로 각 채널상태에 따라 최대한의 전송률을 얻기 위한 변조 및 코딩 방식이 선택되므로 공통 MCS 레벨을 척용한 경우에 비하여 전송률 성 능이 우수함을 보였다 . 특히 독립적인 MCS 레벨을 적용한 AMC-V-BLAST 결합 시스템의 약 $7dB{\sim}9dB$ SNR 구간에서 700kbps 개선을 확인하였다.

ILL-VERSUS WELL-POSED SINGULAR LINEAR SYSTEMS: SCOPE OF RANDOMIZED ALGORITHMS

  • Sen, S.K.;Agarwal, Ravi P.;Shaykhian, Gholam Ali
    • Journal of applied mathematics & informatics
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    • 제27권3_4호
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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.

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Statistical Extraction of Speech Features Using Independent Component Analysis and Its Application to Speaker Identification

  • Jang, Gil-Jin;Oh, Yung-Hwan
    • The Journal of the Acoustical Society of Korea
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    • 제21권4E호
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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.

확률적 매칭을 사용한 음성 다이얼링 시스템 (Voice Dialing system using Stochastic Matching)

  • 김원구
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2004년도 춘계학술대회 학술발표 논문집 제14권 제1호
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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.

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웨이블릿 계수와 Dynamic Positional Warping을 통한 EOG기반의 사용자 독립적 시선인식 (EOG-based User-independent Gaze Recognition using Wavelet Coefficients and Dynamic Positional Warping)

  • 장원두;임창환
    • 한국멀티미디어학회논문지
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    • 제21권9호
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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.

A Dead Time Compensation Algorithm of Independent Multi-Phase PMSM with Three-Dimensional Space Vector Control

  • Park, Ouk-Sang;Park, Je-Wook;Bae, Chae-Bong;Kim, Jang-Mok
    • Journal of Power Electronics
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    • 제13권1호
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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.

Statistical Extraction of Speech Features Using Independent Component Analysis and Its Application to Speaker Identification

  • 장길진;오영환
    • 한국음향학회지
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    • 제21권4호
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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.

영국 녹지 정책과 녹지 평가 발달에 대한 이해: Green Flag Award를 중심으로 (An understanding of green space policies and evaluation tools in the UK: A focus on the Green Flag Award)

  • 남진보;김남춘
    • 한국환경복원기술학회지
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    • 제22권1호
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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.

준역행렬과 투영행렬을 이용한 구속 다물체계의 동역학 해석 (A dynamic analysis for constrained multibody systems using pseudo-inverse and projection matrix)

  • 김외조;유완석
    • 대한기계학회논문집A
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    • 제22권1호
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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.

쇼륨 실내디자인 계획 방향에 관한 연구 (A Study on the Planning for Interior Design of Showroom)

  • 김경순
    • 한국실내디자인학회논문집
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    • 제7호
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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.

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