• 제목/요약/키워드: spectral sequence

검색결과 180건 처리시간 0.028초

DEPTH OF TOR

  • Choi, Sang-Ki
    • 대한수학회보
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    • 제37권1호
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    • pp.103-108
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    • 2000
  • Using spectral sequences we calculate the highest nonvanishing index of Tor for modules of finite projective dimension. The result is applied to compute the depth of the highest nonvanishing Tor. This is one of the cases when a problem of Auslander is positive.

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CIRCULANT AND NEGACYCLIC MATRICES VIA TETRANACCI NUMBERS

  • Ozkoc, Arzu;Ardiyok, Elif
    • 호남수학학술지
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    • 제38권4호
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    • pp.725-738
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    • 2016
  • In this paper, the explicit determinants of the circulant and negacyclic matrix involving Tetranacci sequence $M_n$ and Companion-Tetranacci sequence $K_n$ are expressed by using only Tetranacci sequence $M_n$ and Companion-Tetranacci sequence $K_n$. Also euclidean norms and spectral norms of circulant and negacyclic matrices have been obtained.

ON THE SPECTRAL RADIUS AND INVERTIBILITY OF CERTAIN ELEMENTS IN BANACH ALGEBRA

  • Park, Kyon-Hong;Kim, Byung-Do
    • Journal of applied mathematics & informatics
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    • 제4권1호
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    • pp.299-308
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    • 1997
  • In this paper we show that the limit of a convergent in-vertible sequence in the set of invertible elements Inv(A) in a Banach algebra A under a certain conditions is invertible and we investigate some properties of the spectral radius of banach algebra with unit.

Mass-Spectral Identification of an Extracellular Protease from Bacillus subtilis KCCM 10257, a Producer of Antibacterial Peptide Subtilein

  • SONG HYUK-HWAN;GIL MI-JUNG;LEE CHAN
    • Journal of Microbiology and Biotechnology
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    • 제15권5호
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    • pp.1054-1059
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    • 2005
  • An extracellular protease was identified from Bacillus subtilis KCCM 10257 by N-terminal sequencing and mass spectral analysis. The molecular mass of the extracellular protease was estimated to be 28 kDa by SDS-PAGE. Sequencing of the N-terminal of the protease revealed the sequence of A(G,S,R)QXVPYG(A)V(P,L)SQ. The N-terminal sequence exhibited close similarity to the sequence of other proteases from Bacillus sp. A mass list of the monoisotopic peaks in the MALDI-TOF spectrum was searched after peptide fragmentation of the protease. Six peptide sequences exhibiting monoisotopic masses of 1,276.61, 1,513.67, 1,652.81, 1,661.83, 1,252.61, and 1,033.46 were observed from the fragmented protease. These monisotopic masses corresponded to the lytic enzyme L27 from Bacillus subtilis 168, and the Mowse score was found to be 75. A doubly charged Top product (MS) at a m/z of 517.3 exhibiting a molecular mass of 1034.6 was further analyzed by de novo sequencing using a PE Sciex QSTAR Hybrid Quadropole-TOF (MS/MS) mass spectrometer. MS/MS spectra of the Top product (MS) at a m/z of 517.3 obtained from the fragmented peptide mixture of protease with Q-star contained the b-ion series of 114.2, 171.2, 286.2, 357.2, 504.2, 667.4, 830.1, and 887.1 and y-ion series of 147.5, 204.2, 367.2, 530.3, 677.4, 748.4, 863.4, and 920.5. The sequence of analyzed peptide ion was identified as LGDAFYYG from the b- and y-ion series by de novo sequencing and corresponded to the results from the MALDI-TOF spectrum. From these results the extracellular protease from Bacillus subtilis KCCM 10257 was successfully identified with the lytic enzyme L27 from Bacillus subtilis 168.

Calibrations of Ultraviolet Excess as Metallicity Indicator of F,G,K Stars

  • Ann, Hong-Bae
    • 천문학논총
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    • 제1권1호
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    • pp.39-54
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    • 1984
  • For F,G,K stars, their photometric data and metallicity, [Fe/H] are collected and their correlations between $\delta$(U-B) and [Fe/H] for each spectral group are examined, using a reference sequence which is defined by the stars in Woolley's catalogue and other reference sequences. Detailed examination shows that the reference sequence by Woolley's catalogue appears to be properly defined for the calculation of $\delta$(U-B) of population I stars in the solar neighborhood. It is suggested that accuracies of metallicities derived from $\delta$(U-B) can be improved if we derive the correlations between [Fe/H] and $\delta$(U-B) from the stars in each spectral group.

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OFDM 통신시스템의 PAPR 저감을 위한 더미 시퀀스 삽입 (Dummy Sequence Insertion for PAPR Reduction of OFDM Communication System)

  • 이재은;유흥균;정영호;함영권
    • 한국전자파학회논문지
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    • 제14권12호
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    • pp.1239-1247
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    • 2003
  • OFDM(orthogonal frequency division multiplexing) 통신 방식은 무선 고속 데이터 전송에 적합한 방식이다. 하지만 높은 PAPR(peak-to-average power ratio)의 발생으로 HPA(high power amplifier)에서 비선형 왜곡된다. 따라서 본 논문에서는 일정량의 부반송파를 PAPR 저감을 위해 사용하지만 별도의 부가정보 전송이 필요하지 않는 DSI(dummy sequence insertion) OFDM을 제안한다. DSI 방식은 기존 PTS(partial transmit sequence)나 SLM(selected mapping) 방식에서의 부가 정보와 달리 단지 PAPR 감소에만 사용되는 특정한 더미 데이터 시퀀스(dummy data sequence)를 전송한다. 더미 시퀀스로 상보 시퀀스(complementary sequence)와 상관 시퀀스(correlation sequence)를 사용하고 좀더 효과적 인 PAPR 저감을 위해 플리핑(flipping) 방법을 사용한다. 또한 DSI 방식은 기존의 블록코딩 방식보다 나은 전송 효율(spectral efficiency)을 갖는다. 그리고 DSI 방식은 처리시간 및 계산량을 줄이기 위해 threshold 기법을 적용한다. 하지만 PAPR 저감 성능은 기존 방식보다 떨어진다. 하지만 제안한 DSI 방식의 중요한 장점은 더미 데이터 시퀀스의 손상에 의해 BER특성이 영향을 받지 않는다는 것이다. 결론적으로 DSI 방식은 OFDM 보다 낮은 PAPR을 갖고 기존의 PIS나 SLM에 비해 처리시간을 감소시키고 BER성능 개선이 이루어진다.

가산잡음환경에서 강인음성인식을 위한 은닉 마르코프 모델 기반 손실 특징 복원 (HMM-based missing feature reconstruction for robust speech recognition in additive noise environments)

  • 조지원;박형민
    • 말소리와 음성과학
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    • 제6권4호
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    • pp.127-132
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    • 2014
  • This paper describes a robust speech recognition technique by reconstructing spectral components mismatched with a training environment. Although the cluster-based reconstruction method can compensate the unreliable components from reliable components in the same spectral vector by assuming an independent, identically distributed Gaussian-mixture process of training spectral vectors, the presented method exploits the temporal dependency of speech to reconstruct the components by introducing a hidden-Markov-model prior which incorporates an internal state transition plausible for an observed spectral vector sequence. The experimental results indicate that the described method can provide temporally consistent reconstruction and further improve recognition performance on average compared to the conventional method.

ON THE NORMS OF SOME SPECIAL MATRICES WITH GENERALIZED FIBONACCI SEQUENCE

  • RAZA, ZAHID;ALI, MUHAMMAD ASIM
    • Journal of applied mathematics & informatics
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    • 제33권5_6호
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    • pp.593-605
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    • 2015
  • In this study, we define r-circulant, circulant, Hankel and Toeplitz matrices involving the integer sequence with recurrence relation Un = pUn-1 + Un-2, with U0 = a, U1 = b. Moreover, we obtain special norms of above mentioned matrices. The results presented in this paper are generalizations of some of the results of [1, 10, 11].

SRLS을 이용한 파라미터 추정에 관한 연구 (A study on the parameter estimate using selective recursive least square)

  • 유치형;이재하;정찬수
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1989년도 한국자동제어학술회의논문집; Seoul, Korea; 27-28 Oct. 1989
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    • pp.441-444
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    • 1989
  • This correspondence presents a recursive estimation algorithm which, unlike conventional ones; updates the estimates only when a sufficient improvement can be obtained with a bounded noise assumption, the resulting sequence of estimates is a sequence of convex sets(ellipsoids) in the parameter space. For the cases studied, the algorithm use less than 20 percent of the. data to update, the estimate and still acquired good accuracy for spectral estimation.

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UNIVARIATE TRUNCATED MOMENT PROBLEMS VIA WEAKLY ORTHOGONAL POLYNOMIAL SEQUENCES

  • Seonguk Yoo
    • East Asian mathematical journal
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    • 제40권1호
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    • pp.25-36
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    • 2024
  • Full univariate moment problems have been studied using continued fractions, orthogonal polynomials, spectral measures, and so on. On the other hand, the truncated moment problem has been mainly studied through confirming the existence of the extension of the moment matrix. A few articles on the multivariate moment problem implicitly presented about some results of this note, but we would like to rearrange the important results for the existence of a representing measure of a moment sequence. In addition, new techniques with orthogonal polynomials will be introduced to expand the means of studying truncated moment problems.