• Title/Summary/Keyword: spectrum and point spectrum

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고차진동모드의 영향을 고려한 충지진하중 (The Effect of Higher Vibration Modes on the Design Seismic Load)

  • 이동근;이석용;신용우
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1990년도 가을 학술발표회 논문집
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    • pp.73-78
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    • 1990
  • In current practice of earthquake resistant design the equivalent lateral force procedure is widely used for its simplicity and convenience. But the equivalent lateral force procedure is derived based on the assumption that the dynamic behavior of the structure is governed primarily by the fundamental vibration mode. Therefore proper prediction of dynamic responses of the structure is unreliable using the equivalent lateral force procedure when the effect of higher vibration modes on the dynamic behavior is negligible. In this study design seismic load which can reflect the effect of higher vibration modes is proposed from the point of view of proper assessment of story shears which have the major influence on the design moment of beams and columns. To evaluate the effect of higher modes, differences between the story force based on the equivalent lateral force procedure specified in current earthquake resistance building code and the one based on modal analysis using design spectrum are examined. From these results improved design seismic load for the equivalent lateral force procedure which can reflect the effect of higher vibration modes is proposed.

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성악 전공 학생의 가칭 시 음성의 SPR(Singing Power Ratio)에 관한 연구 (A Study of the SPR (Singing Power Ratio) on the Singing Voice in Singing Students)

  • 조성미;정옥란;이상욱
    • 음성과학
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    • 제11권4호
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    • pp.121-127
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    • 2004
  • This study attempted to provide a spectrum analysis for quantitative evaluation of singing voice quality of singing students rather than the presence or absence of the singer's formant. The regression analysis was used to analyse the relationship between ringing quality, SPR, and SPP of singing voice of college student subjects majoring in music. This study measured singing. power ratio (SPR) in 41 singing students. Digital audio recordings were made in sung vowels for acoustic analyses. Each sample was judged by 1 experienced singing teacher and 4 voice pathologists on one semantic bipolar 7-point scales (ringing-dull). The results showed that the SPR and SPP had significant correlations with ringing quality. The SPR had a significant relationship with ringing quality on singing voice in singing students. The SPR can be an important quantitative measurement for evaluating singing voice quality.

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300톤급 채낚기 어선의 공중소음 특성 (Noise characteristics in a jigging fishing vessel of 300 tons class)

  • 이유원;김욱성
    • 수산해양기술연구
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    • 제48권1호
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    • pp.91-98
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    • 2012
  • This study is aimed to utilize a basic data for setting up an allowable air noise with IMO standard in accommodation and working areas of 24m longer fishing vessels. The air noise in accommodation and working areas of 300 tons class squid-jigger were evaluated and the levels were compared to the allowable levels of IMO. The results indicated that the maximum range of noise levels was estimated to be between 54.8dB (A) and 83.2dB, and the correlation between the distance from the main engine to measuring point and the maximum noise level of each point was shown to be y=-13.8log (r)+92.91 ($r^2=0.821$). In addition, except the case of making an accommodation area near to the engine room in 24m longer jigging vessels, it was evaluated that the accommodation noise regulation of 1,600 tons international voyage vessels with 60dB (A) or an improved noise level with 65dB (A) could be properly applied.

Ionized Cluster Beam 증착방법을 이용한 Indium-Tin-Oxide(ITO) 박막의 제작과 그 특성에 관한 연구 (A Study on the Fabrication and Characteristics of ITO thin Film Deposited by the Ionized Cluster Beam Deposition)

  • 최성창;황보상우;조만호;김남영;홍창의;이덕형;심태언;황정남
    • 한국진공학회지
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    • 제5권1호
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    • pp.54-61
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    • 1996
  • Indium-tin oxide (ITO) films were deposited on the glass substrate by the reactive -ionized cluster beam deposition(ICBD) method. In the oxygen atmosphere, indium cluster formed through the nozzle is ionized by the electron bombardment and is accelerated to be deposited on the substrate. And tin is simultaneoulsy evaporated from the boron-nitride crucible. The chracteristics of films were examined by the X-ray photoelectron spectroscopy(XPS), glancing angle X-ray diffractrion(GXRD) and the electrical properties. were measured by 4-point-probe and Hall effect measurement system . From the XPS spectrum , it was found that indium and tin atoms combined with the oxygen to form oxide$(In_2O_3, SnO_2)$. In the case of films with high tin-concentration, the GXRD spectra show that the main $In_2O_3$ peak of (222) plane, but also sub peaks((440) peak etc.) and $SnO_2$ peaks were detected. From that results, itis concluded that the heavily dopped tin component (more than 14 at. %) disturbs to form $In_2O_3$(222) phase. Four-point-probe and Hall effect measurement show that, in the most desirable case, the transmittance of the films is more then 90% in visible range and its resistivity is $$\rho$=3.55 \times10^{-4}\Omega$cm and its mobility is $\mu$=42.8 $\textrm{cm}^2$/Vsec.

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Self-organized Spectrum Access in Small-cell Networks with Dynamic Loads

  • Wu, Ducheng;Wu, Qihui;Xu, Yuhua
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제10권5호
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    • pp.1976-1997
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    • 2016
  • This paper investigates the problem of co-tier interference mitigation for dynamic small- cell networks, in which the load of each small-cell varies with the number of active associated small-cell users (SUs). Due to the fact that most small-cell base stations (SBSs) are deployed in an ad-hoc manner, the problem of reducing co-tier interference caused by dynamic loads in a distributed fashion is quite challenging. First, we propose a new distributed channel allocation method for small-cells with dynamic loads and define a dynamic interference graph. Based on this approach, we formulate the problem as a dynamic interference graph game and prove that the game is a potential game and has at least one pure strategy Nash equilibrium (NE) point. Moreover, we show that the best pure strategy NE point minimizes the expectation of the aggregate dynamic co-tier interference in the small-cell network. A distributed dynamic learning algorithm is then designed to achieve NE of the game, in which each SBS is unaware of the probability distributions of its own and other SBSs' dynamic loads. Simulation results show that the proposed approach can mitigate dynamic co-tier interference effectively and significantly outperform random channel selection.

스펙트럼 패턴 기반의 잡음 환경에 강인한 음성의 끝점 검출 기법 (Spectral Pattern Based Robust Speech Endpoint Detection in Noisy Environments)

  • 박진수;이윤재;이인호;고한석
    • 말소리와 음성과학
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    • 제1권4호
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    • pp.111-117
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    • 2009
  • In this paper, a new speech endpoint detector in noisy environment is proposed. According to the previous research, the energy feature in the speech region is easily distinguished from that in the speech absent region. In conventional method, the endpoint can be found by applying the edge detection filter that finds the abrupt changing point in feature domain. However, since the frame energy feature is unstable in noisy environment, the accurate edge detection is not possible. Therefore, in this paper, the novel feature extraction method based on spectrum envelop pattern is proposed. Then, the edge detection filter is applied to the proposed feature for detection of the endpoint. The experiments are performed in the car noise environment and a substantial improvement was obtained over the conventional method.

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CLIFFORD $L^2$-COHOMOLOGY ON THE COMPLETE KAHLER MANIFOLDS II

  • Bang, Eun-Sook;Jung, Seoung-Dal;Pak, Jin-Suk
    • 대한수학회보
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    • 제35권4호
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    • pp.669-681
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    • 1998
  • In this paper, we prove that on the complete Kahler manifold, if ${\rho}(x){\geq}-\frac{1}{2}{\lambda}_0$ and either ${\rho}(x_0)>-\frac{1}{2}{lambda}_0$ at some point $x_0$ or Vol(M)=${\infty}$, then the Clifford $L^2$ cohomology group $L^2{\mathcal H}^{\ast}(M,S)$ is trivial, where $\rho(x)$ is the least eigenvalue of ${\mathcal R}_x + \bar{{\mathcal R}}(x)\;and\;{\lambda}_0$ is the infimum of the spectrum of the Laplacian acting on $L^2$-functions on M.

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A bipolar IR feature near the center of $\gamma$-ray SNR G353.6-0.7

  • Kim, Il-Joong;Seon, Kwang-Il;Koo, Bon-Chul
    • 천문학회보
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    • 제35권2호
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    • pp.70.1-70.1
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    • 2010
  • 최근에 새롭게 발견된 초신성잔해 G353.6-0.7은 $\gamma$-ray source로부터 발견된 최초의 초신성 잔해이다. 이 초신성잔해의 중앙에서는 밝은 X-ray compact source, XMMU J173203.3-344518이 발견되었다. 우리는 위 X-ray compact source 근처에 IR source, IRAS 17287-3443이 매우 가까이 있음을 발견하고, Spitzer data를 이용하여 이 IR source에 대하여 자세히 분석한다. 24 um image에서 IR source는 bipolar feature를 보이며, 매우 강한 중앙지역은 8 um 에서도 extended feature를 보여준다. Spitzer IRS spectrum에서는 [Ne II] 12.88 um 방출선이 강하게 나오는 것이 특징이며, 우리는 또한 이 IR source에 embedded 된 것으로 의심되는 point source를 분석한다.

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원심압축기 스톨 발단에 관한 실험적 연구 (I) - 스톨 발단 과정 - (Experimental Study on Stall Inception in a High-Speed Centrifugal Compressor (I) - inception Type -)

  • 강정식;강신형
    • 대한기계학회논문집B
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    • 제25권10호
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    • pp.1436-1444
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    • 2001
  • Stall inception in a high-speed centrifugal compressor has been examined. The main objective was to find stall precursor and to develop a reliable stall warning method. Eight equally spaced fast-response pressure transducers in the inducer detected the spatial structure of small amplitude perturbations, via spatial Fourier transform, as stall is approached. Near the stall inception point, the phase of spatial courier coefficients increased linearly with the speed of impeller relation for several impeller revolutions at all test speeds, and the spectrum at impeller frequency increased as stall is approached. These are the clear evidences that the impeller frequency participates in the stalling process.

Purification and Characterization of Cop, a Protein Involved in the Copy Number Control of Plasmid pE194

  • Kwak, Jin-Hwan;Kim, Jung-Ho;Kim, Mu-Yong;Choi, Eung-Chil
    • Archives of Pharmacal Research
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    • 제21권3호
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    • pp.291-297
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    • 1998
  • Cop protein has been overexpressed in Escherichia coli using a T7 RNA polymerase system. Purification to apparent homogeneity was achieved by the sequential chromatography on ion exchange, affinity chromatography, and reverse phase high performance liquid chromatography system. The molecular weight of the purified Cop was estimated as 6.1 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). But the molecular mass of the native state Cop was shown to be 19 kDa by an analytical high performance size exclusion chromatography, suggesting a trimer-like structure in 50 mM Tris-HCI buffer (pH 7.5) containing 100 mM NaCl. Cop protein Was calculated to contain $39.1% {\alpha}-helix, 16.8% {\beta}-sheet$, 17.4% turn, and 26.8% random structure. The DNA binding property of Cop protein expressed in E. coli Was preserved during the expression and purification process. The isoelectric point of Cop was determined to be 9.0. The results of amino acid composition analysis and N-terminal amino acid sequencing of Cop showed that it has the same amino acid composition and N-terminal amino acid sequence as those deduced from its DNA sequence analysis, except for the partial removal of N-terminal methionine residue by methionyl-aminopeptidase in E. coli.

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