• 제목/요약/키워드: divergence time

검색결과 180건 처리시간 0.023초

시계열 신호의 흔돈분석 기법 소개: 해양 수중소음 신호를 중심으로 (Introduction to Chaos Analysis Method of Time Series Signal: With Priority Given to Oceanic Underwater Ambient Noise Signal)

  • 최복경;김봉채;신창웅
    • Ocean and Polar Research
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    • 제28권4호
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    • pp.459-465
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    • 2006
  • Ambient noise as a background noise in the ocean has been well known for its the various and irregular signal characteristics. Generally, these signals we treated as noise and they are analyzed through stochastical level if they don't include definite sinusoidal signals. This study is to see how ocean ambient noise can be analyzed by the chaotic analysis technique. The chaotic analysis is carried out with underwater ambient noise obtained in areas near the Korean Peninsula. The calculated physical parameters of time series signal are as follows: histogram, self-correlation coefficient, delay time, frequency spectrum, sonogram, return map, embedding dimension, correlation dimension, Lyapunov exponent, etc. We investigate the chaotic pattern of noises from these parameters. From the embedding dimensions of underwater noises, the assesment of underwater noise by chaotic analysis shows similar results if they don't include a definite sinusoidal signal. However, the values of Lyapunov exponent (divergence exponent) are smaller than that of random noise signal. As a result we confirm the possibility of classification of underwater noise using Lyapunov analysis.

The Regional Economic Impacts of Taiwan High Speed Rail

  • Huang, Hank C.C.;Hsu, Tao Hsin;Lin, Cynthia M.T.
    • International Journal of Railway
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    • 제1권1호
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    • pp.12-19
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    • 2008
  • Starting her business operation on January 5 2007, Taiwan High Speed Rail(THSR) shapes a new time-space frame for Taiwan western corridor, where more than 90% of national population lives around and more than 95% gross domestic product created from. Comparing with the four-hour traveling time by highway before 2007, THSR reduces the time required to one and half hours from Taipei to Kaohsiung. It will not only benefit the communication along the island from north to south, but also change the location advantages/disadvantages for all cities in these regions. Therefore, this paper establishes a spatial computable general equilibrium model(SCGE Model) to simulate the economic effect of High Speed Rail(HSR). This SCGE model divides Taiwan economy into fifteen geographic regions and thirteen industries. Each region has three sectors: household sector, transportation sector, and industries sector. Following the behavior function of economic theories, the general equilibrium can be achieved simultaneously. Thus, gross regional product (GRP), capital formation, employment income and welfare/utility level can be all observed by calculating the different economic result between cases with-/ without-HSR. Besides, this model presents the social welfare benefit from HSR operation, the polarization phenomenon among regions and within certain region, unbalance distribution of welfare along the HSR line, and industries development divergence among regions etc. These major findings should be useful for regional development policy making.

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The Regional Economic Impacts of Taiwan High Speed Rail

  • Huang, Hank C.C.;Hsu, Tao Hsin;Lin, Cynthia M.T.
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2007년도 추계학술대회 논문집
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    • pp.1896-1912
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    • 2007
  • Starting her business operation on January 5 2007, Taiwan High Speed Rail (THSR) shapes a new time-space frame for Taiwan western corridor, where more than 90% of national population lives around and more than 95% gross domestic product created from. Comparing with the four-hour traveling time by highway before 2007, THSR reduces the time required to one and half hours from Taipei to Kaohsiung. It will not only benefit the communication along the island from north to south, but also change the location advantages/disadvantages for all cities in these regions. Therefore, this paper establishes a spatial computable general equilibrium model (SCGE Model) to simulate the economic effect of High Speed Rail (HSR). This SCGE model divides Taiwan economy into fifteen geographic regions and thirteen industries. Each region has three sectors: household sector, transportation sector, and industries sector. Following the behavior function of economic theories, the general equilibrium can be achieved simultaneously. Thus, gross regional product (GRP), capital formation, employment income and welfare/utility level can be all observed by calculating the different economic result between cases with-/ without-HSR. Besides, this model presents the social welfare benefit from HSR operation, the polarization phenomenon among regions and within certain region, unbalance distribution of welfare along the HSR line, and industries development divergence among regions etc. These major findings should be useful for regional development policy making.

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Identification and Expression Analyses of Equine Endogenous Retroviruses in Horses

  • Gim, Jeong-An;Kim, Heui-Soo
    • Molecules and Cells
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    • 제40권10호
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    • pp.796-804
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    • 2017
  • Endogenous retroviruses (ERVs) have been integrated into vertebrate genomes and have momentously affected host organisms. Horses (Equus caballus) have been domesticated and selected for elite racing ability over centuries. ERVs played an important role in the evolutionary diversification of the horse genome. In the present study, we identified six equine ERV families (EqERVs-E1, I1, M2, P1, S1, and Y4), their full-length viral open reading frames (ORFs), and elucidated their phylogenetic relationships. The divergence time of EqERV families assuming an evolutionary rate of 0.2%/Myr indicated that EqERV-S3 (75.4 million years ago; mya) on chromosome 10 is an old EqERV family and EqERV-P5 (1.2 Mya) on chromosome 12 is a young member. During the evolutionary diversification of horses, the EqERV-I family diverged 1.7 Mya to 38.7 Mya. Reverse transcription quantitative real-time PCR (RT-qPCR) amplification of EqERV pol genes showed greater expression in the cerebellum of the Jeju horse than the Thoroughbred horse. These results could contribute further dynamic studies for horse genome in relation to EqERV gene function.

히로시 스기모토의 사진작품에 드러나는 무한성의 건축적 발현에 대한 연구 (Architectural Manifestation of Hiroshi Sugimoto's Photographic Infinity)

  • 안성모
    • 한국실내디자인학회논문집
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    • 제24권5호
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    • pp.31-41
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    • 2015
  • The objective of this research is to investigate the artistic meaning of "infinity," manifested by the fourth dimensional value in the genres of photography and architecture, by analyzing how Sugimoto Hiroshi's photographic spatio-temporal infinity transfers to his architectural approaches. The research is initiated by scrutinizing the themes, characteristics, techniques, and artistic meaning of Sugimoto's famous photographic series, including "Seascapes," "Theatres," and "Architecture"; the concept of infinity can be defined as infinite divergence and infinitesimal convergence between antithetical concepts in time, space, and being. Sugimoto's photographic works display "temporal infinity" by connecting ancient times, the present, and the future; "spatial infinity" by offering the potential for transformation from flat photographs into infinite three-dimensional space and fourth-dimensional concepts through time; and "existential infinity" of life and death by making us think about being and essence, being and time, and origin and religion. These perspectives are also used to analyze Sugimoto's architectural works, such as "Appropriate Proportion" and "Glass Tea House Mondrian." As a result, the research finds that in Sugimoto's architectural approaches, spatio-temporal infinity between antithetical values is manifested through the concept of origin, geometric form, extended axis, immaterial threshold, transparent materiality, and connectivity of light and shadow, provoking our existence to transcend into infinity itself.

A New PVC-Membrane Electrode Based on a Thia-Substituted Macrocyclic Diamide for Selective Potentiometric Determination of Silver Ion

  • Shamsipur, Mojtaba;Kazemi, Sayed Yahya;Niknam, Khodabaksh;Sharghi, Hashem
    • Bulletin of the Korean Chemical Society
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    • 제23권1호
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    • pp.53-58
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    • 2002
  • A new PVC-membrane electrode for $Ag^+$ ion based on a thia-substituted macrocyclic diamide has been prepared. The electrode exhibited a Nernstian response for $Ag^+$ over a wide concentration range $(1.7{\times}10^{-6}-1.0{\times}10^{-1}M)$. It has a response time <15 s and can be used for at least 3 months without divergence. The proposed membrane sensor revealed good selectivities for $Ag^+$ over a variety of metal ions and can be used in a pH range 3.0-7.5. It has been used successfully for direct determination of $Ag^+$ in different real samples and, as an indicator electrode, in the titration of silver ion.

구조물의 품질 결함 변별력 증대를 위한 수직 에너지 기반의 웨이블릿 Feature 생성 (Structural Quality Defect Discrimination Enhancement using Vertical Energy-based Wavelet Feature Generation)

  • 김준석;정욱
    • 품질경영학회지
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    • 제36권2호
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    • pp.36-44
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    • 2008
  • In this paper a novel feature extraction and selection is carried out in order to improve the discriminating capability between healthy and damaged structure using vibration signals. Although many feature extraction and selection algorithms have been proposed for vibration signals, most proposed approaches don't consider the discriminating ability of features since they are usually in unsupervised manner. We proposed a novel feature extraction and selection algorithm selecting few wavelet coefficients with higher class discriminating capability for damage detection and class visualization. We applied three class separability measures to evaluate the features, i.e. T test statistics, divergence, and Bhattacharyya distance. Experiments with vibration signals from truss structure demonstrate that class separabilities are significantly enhanced using our proposed algorithm compared to other two algorithms with original time-based features and Fourier-based ones.

진동하는 충돌 제트의 스케일링과 효율적인 수치 모사 (EFFICIENT SIMULATION AND SCALING OF OSCILLATORY IMPINGING JETS)

  • 김성인;박승오;홍승규;이광섭
    • 한국전산유체공학회지
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    • 제10권4호통권31호
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    • pp.32-38
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    • 2005
  • Present study simulates oscillatory supersonic impinging jet flows using the axisymmetric Navier-Stokes code. To capture the salient features of flow oscillation and overcome the divergence during the initial transient period, several tests have been conducted for the grid and time step sizes. The results also show that the effects of the inlet flow condition at the nozzle exit and turbulence on the oscillatory behavior of supersonic impinging jets are negligible. Frequencies of the surface pressure oscillation obtained by the selected numerical method are in good accord with the measured impinging tones for various cases of nozzle-to-plate distance. Two seemingly different staging behaviors with nozzle-to-plate distance and nozzle pressure variations are found to correlate well if the frequency and distance are normalized by the length of the first shock cell.

Modal Analysis법에 의한 무주대공간 구조물의 좌굴해석 (Buckling Analysis of the Large Span Spatial Structures by Modal Analysis)

  • 한상을;권택진
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1996년도 가을 학술발표회 논문집
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    • pp.195-201
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    • 1996
  • This paper is mainly forcused on the application of modal analysis In analyze the geometrically non-linear buckling behaviors of large span spatial structures, and the evaluation of each eigen mode affected post-buckling behaviors and buckling loads. Modal analysis is applied . to derivation of the system matrices transforming actual displacement space into generalized coordinates space represented by coefficients multiplied in the linear combination of eigen modes which are independent and orthogonal each other. By using modal analysis method, it will be expected to save the calculating time by computer extremely. For example, we can obtain the satisfactorily good results by using about 7% of total eigen modes only in case of single layer latticed dome. And we can decrease the possibility of divergence on the bifurcation point in the calculation of post-buckling path. Arc-length method and Newton-Raphson iteration method are used to calculate the nonlinear equilibrium path.

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가변 파라미터를 갖는 비선형 퍼지 PID 제어기에 관한 연구 (A Study on the Nonlinear Fuzzy PID Controller with Variable Parameters)

  • 이병결;김인환;김종화
    • 한국지능시스템학회논문지
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    • 제15권2호
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    • pp.127-134
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    • 2005
  • 본 논문은 고정 파라미터를 갖는 퍼지 PID 제어기의 퍼지화 과정에서 입력공간의 제한으로 제어입력이 제한되어 발생하는 제어시스템의 상승시간 지연과 불안정성을 개선하기 위해 가변 파라미터를 갖는 퍼지 PID 제어기를 제안하고 설계방법과 추종성능을 기술한다. 제어기의 파라미터는 소이득정리로부터 제어시스템의 BIBO 안정도 조건을 만족하도록 가변되어 전체 제어시스템에 대한 BIBO 안정도를 만족시킨다.