• Title/Summary/Keyword: difference sequence

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Adaptive SLM Scheme Based on Peak Observation for PAPR Reduction of OFDM Signals (OFDM PAPR 감소를 위한 피크 신호 관찰 기반의 적응적 SLM 기법)

  • Yang, Suck-Chel;Shin, Yoan
    • Proceedings of the IEEK Conference
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    • 2006.06a
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    • pp.15-16
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    • 2006
  • In this paper, we propose an adaptive SLM scheme based on peak observation for PAPR reduction of OFDM signals. The proposed scheme is composed of three steps: peak scaling, sequence selection, and SLM procedures. In the first step, the peak signal samples in the IFFT outputs of the original input sequence are scaled down. In the second step, the sub-carrier positions where power difference between the original input sequence and the FFT outputs of the scaled signal is large, are identified. Then, the phase sequences which have the maximum number of phase-reversed sequence words only for these positions, are selected. Finally, only using the selected phase sequences, the generic SLM procedure is performed for the original input sequence. Simulation results reveal that the proposed adaptive SLM remarkably reduces the complexity in terms of IFFT and PAPR calculations than the conventional SLM, while maintaining the PAPR reduction performance.

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Image Sequence Compression based on Adaptive Classification of Interframe Difference Image Blocks (프레임간 차영상 블록의 적응분류에 의한 영상시퀀스 압축)

  • Ahn, Chul-Joon;Kong, Seong-Gon
    • Journal of the Korean Institute of Intelligent Systems
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    • v.8 no.6
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    • pp.122-128
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    • 1998
  • This paper presents compression of image sequences based on the classification of interframe difference image blocks. classification process consists of image activity classification and energy distribution classification. In the activity classification, interframe difference image blocks are classified into activity blocks and non-activity blocks using the edge detection. In the distribution classification, activity blocks are further classified into vertical blocks, horizontal blocks, and small activity blocks using the AC energy distribution features. The RBFN, trained with numerical classification results, successfully classifies difference image blocks according to image details. Image sequence compressing based on the classification of interframe difference image blocks using the RBFN shows better compression results and less training time than the classical sorting method and the MLP network.

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Control of DC-side Voltage Unbalance among Phases in Multi-level H-Bridge STATCOM with Unbalanced Load (불평형부하를 가지는 다단 H-bridge STATCOM에서 상간 직류전압 불평형의 제어)

  • Kwon, Byung-Ki;Jung, Seung-Ki;Kim, Tae-Hyeong
    • The Transactions of the Korean Institute of Power Electronics
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    • v.19 no.4
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    • pp.332-341
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    • 2014
  • A cascaded H-bridge multi-level STATCOM(STATic synchronous COMpensator), which is composed of many cell inverters with independent dc-sources, generates inevitably dc-side voltage unbalance among phases when it compensates unbalanced load. It comes from the difference of flowing active power in each phase when this compensator makes negative-sequence current to eliminate the unbalance of source-side current. However, this unbalance can be controlled by injecting zero-sequence current which is decoupled with grid currents, so the compensator can work well during this balancing process. Both a feedback control algorithm, which produces zero-sequence current proportional to dc-side voltage unbalance within each phase, and a feedforward control algorithm, which makes zero-sequence current directly from the compensator's negative-sequence current, were proposed. The dc-side voltage of each phase can be controlled stably by these proposed algorithms in both steady-state and transient, so the compensator can have fast response to satisfy control performance under rapid changing load. These balancing controllers were implemented and verified via simulation and experiment.

ALMOST PERIODIC SOLUTIONS OF LINEAR DIFFERENCE SYSTEMS

  • Im, Dong Man;Goo, Yoon Hoe
    • Journal of the Chungcheong Mathematical Society
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    • v.19 no.2
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    • pp.153-158
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    • 2006
  • In this paper, we present an elementary proof for the existence of almost periodic solutions of linear nonhomogeneous difference systems.

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ON THE RECURSIVE SEQUENCE $x_{n+l} =\alpha+\frac{x_{n-1}^{p}}{x_{n}^{p}}$

  • STEVIC STEVO
    • Journal of applied mathematics & informatics
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    • v.18 no.1_2
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    • pp.229-234
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    • 2005
  • The boundedness, global attractivity, oscillatory and asymptotic periodicity of the positive solutions of the difference equation of the form $x_{n+l} =\alpha+\frac{x_{n-1}^{p}}{x_{n}^{p}},\;\; n = 0, 1, ...$ is investigated, where all the coefficients are nonnegative real numbers.

Genotyping of avian pathogenic Escherichia coli by DNA fragment analysis for the differences in simple sequence repeats

  • Han, Mi Na;Byeon, Hyeon Seop;Han, Seong Tae;Jang, Rae Hoon;Kim, Chang Seop;Choi, Seok Hwa
    • Korean Journal of Veterinary Service
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    • v.41 no.4
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    • pp.257-262
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    • 2018
  • Avian pathogenic E. coli (APEC) causes severe economic losses in the poultry farms, due to systemic infections leading to lethal colisepticemia. It causes a variety of diseases from air sac infection to systemic spread leading to septicemia. Secondary infection contains opportunistic infections due to immunosuppression disease. Collibacillosis causes the great problems in the poultry industry in Korea. Thus, it is necessary to identify and classify the characteristics of E. coli isolate of chicken origin to confirm the diversity of symptoms and whether they are transmitted among the farms. Fragment analysis is identify the difference in the number of Variable-Number Tandem-Repeats (VNTRs) for genotyping. VNTRs have repeating structure (Microsatellite, Short tandem repeats; STR, Simple sequence repeats; SSR) in the chromosome. This region can be used as a genetic marker because of its high mutation rate. And various lengths of the amplified DNA fragment cause the difference in the number of repetition of the DNA specific site. The number of repetition sequences indicates the separated size of fragments, so the each fragments can be distinguished by specific samples. The results of the sample show that there is no difference in six microsatellite loci (yjiD, aidB, molR_1, ftsZ, b1668, yibA). There are differences among the farms in relation of the number of repetitions of other six microsatellite loci (ycgW, yaiN, yiaB, mhpR, b0829, caiF). Four (ycgW, yiaB, b0829, caiF) of these six microsatellite loci show statistically significant differences (P<0.05). It means that the analysis using four microsatellite loci including ycgW, yiaB, b0829, and caiF can confirm among the farms. Five E. coli samples in one farm have same SSR repetition at all markers. But, there are significant differences from other farms at Four (ycgW, yiaB, b0829, caiF) microsatellite loci. These results emphasize again that the four microsatellite loci makes a difference in the amplified DNA fragments, enabling it to be used for E. coli genotyping.

An Efficient Video Retrieval Algorithm Using Key Frame Matching for Video Content Management

  • Kim, Sang Hyun
    • International Journal of Contents
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    • v.12 no.1
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    • pp.1-5
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    • 2016
  • To manipulate large video contents, effective video indexing and retrieval are required. A large number of video indexing and retrieval algorithms have been presented for frame-wise user query or video content query whereas a relatively few video sequence matching algorithms have been proposed for video sequence query. In this paper, we propose an efficient algorithm that extracts key frames using color histograms and matches the video sequences using edge features. To effectively match video sequences with a low computational load, we make use of the key frames extracted by the cumulative measure and the distance between key frames, and compare two sets of key frames using the modified Hausdorff distance. Experimental results with real sequence show that the proposed video sequence matching algorithm using edge features yields the higher accuracy and performance than conventional methods such as histogram difference, Euclidean metric, Battachaya distance, and directed divergence methods.

On the Fibonacci Almost Convergent Sequence Space and Fibonacci Core

  • DEMIRIZ, SERKAN;KARA, EMRAH EVREN;BASARIR, METIN
    • Kyungpook Mathematical Journal
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    • v.55 no.2
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    • pp.355-372
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    • 2015
  • In the present paper, by using the Fibonacci difference matrix, we introduce the almost convergent sequence space $\hat{c}^f$. Also, we show that the spaces $\hat{c}^f$and $\hat{c}$ are linearly isomorphic. Further, we determine the ${\beta}$-dual of the space $\hat{c}^f$ and characterize some matrix classses on this space. Finally, Fibonacci core of a complex-valued sequence has been introduced, and we prove some inclusion theorems related to this new type of core.

The Compositions of Approaching Sequence in Exterior Space of Tadao Ando′s Works (안도 타다오 건축의 외부공간에 나타난 진입시퀀스의 구성방식)

  • 문정민;안우진;고성룡
    • Korean Institute of Interior Design Journal
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    • no.29
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    • pp.27-34
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    • 2001
  • The concept of homogeneous space which was made in during the modern architecture was criticize for making our circumstances uniformly. The difference of place disappeared. The concept of place, however, has been watching in Contemporary Architecture. A basis for the concept of place is 'movement in space'through the sense of the body. Thus, architectural methods for experiencing place are composing the sequence through the continuous time. It is important that the composition of sequences in place makes the spatial experiences with harmonies of architecture and environments in exterior space for people who enter the building. Tadao Ando makes place in terms of experiencing body. Compositions of sequence in his works are expressed very well at the approaching stages in the process of exterior space. This stud is to survey the compositions of approaching sequence in Tadao Ando's Works.

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