Statistically optimal event detection using small array data

Abstract A generalization of Capon's maximum-likelihood technique for detection and estimation of seismic signals is introduced. By using a multi-dimensional autoregressive approximation of seismic array noise, we have developed a technique to use Capon's multi-channel filter for on-line processing. Such autoregressive adaptation to the curent noise matrix power spectrum is shown to yield good suppression of mutually correlated array noise processes. As an example, this technique is applied to detection of a small Semipalatinsk underground explosion recorded at the ARCESS array.

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The on-line use of histogram data for high-speed correction and alignment of electron microscope images

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100112713 ◽

1984 ◽

Vol 42 ◽

pp. 556-557

Author(s):

William Krakow

Keyword(s):

Power Spectrum ◽

High Speed ◽

Direct Memory Access ◽

Digital Television ◽

Contrast Transfer Function ◽

The Past ◽

High Resolution Tem ◽

On Line ◽

Correction Of Astigmatism ◽

The Fourier Transform

In the past few years on-line digital television frame store devices coupled to computers have been employed to attempt to measure the microscope parameters of defocus and astigmatism. The ultimate goal of such tasks is to fully adjust the operating parameters of the microscope and obtain an optimum image for viewing in terms of its information content. The initial approach to this problem, for high resolution TEM imaging, was to obtain the power spectrum from the Fourier transform of an image, find the contrast transfer function oscillation maxima, and subsequently correct the image. This technique requires a fast computer, a direct memory access device and even an array processor to accomplish these tasks on limited size arrays in a few seconds per image. It is not clear that the power spectrum could be used for more than defocus correction since the correction of astigmatism is a formidable problem of pattern recognition.

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Use of the maximum likelihood technique, for fitting counting distributions

Nuclear Instruments and Methods ◽

10.1016/0029-554x(68)90108-0 ◽

1968 ◽

Vol 65 (3) ◽

pp. 301-306 ◽

Cited By ~ 20

Author(s):

P.H.R. Orth ◽

W.R. Falk ◽

G. Jones

Keyword(s):

Maximum Likelihood ◽

Maximum Likelihood Technique

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Array data processing techniques applied to long-period shear waves at Fennoscandian seismograph stations

Bulletin of the Seismological Society of America ◽

10.1785/bssa0590051863 ◽

1969 ◽

Vol 59 (5) ◽

pp. 1863-1887

Author(s):

James H. Whitcomb

Keyword(s):

Data Processing ◽

Velocity Ratio ◽

Underground Explosion ◽

High Signal ◽

S Wave ◽

Array Data ◽

S Waves ◽

Long Period ◽

Normal Record ◽

The Individual

abstract Array data processing is applied to long-period records of S waves at a network of five Fennoscandian seismograph stations (Uppsala, Umeå, Nurmijärvi, Kongsberg, Copenhagen) with a maximum separation of 1300 km. Records of five earthquakes and one underground explosion are included in the study. The S motion is resolved into SH and SV, and after appropriate time shifts the individual traces are summed, both directly and after weighting. In general, high signal correlation exists among the different stations involved resulting in more accurate time readings, especially for records which have amplitudes that are too small to be read normally. S-wave station residuals correlate with the general crustal type under each station. In addition, the Fennoscandian shield may have a higher SH/SV velocity ratio than the adjacent tectonic area to the northwest.SV-to-P conversion at the base of the crust can seriously interfere with picking the onset of Sin normal record reading. The study demonstrates that, for epicentral distances beyond about 30°, existing networks of seismograph stations can be successfully used for array processing of long-period arrivals, especially the S arrivals.

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SAMPLING SYSTEMS FOR THE BIRCH CASEBEARER (LEPIDOPTERA: COLEOPHORIDAE)

The Canadian Entomologist ◽

10.4039/ent111875-8 ◽

1979 ◽

Vol 111 (8) ◽

pp. 875-882

Author(s):

A. G. Raske ◽

M. Alvo

Keyword(s):

Maximum Likelihood ◽

Sampling Plan ◽

New Method ◽

Betula Papyrifera ◽

White Birch ◽

Destructive Sampling ◽

Damage Level ◽

Sampling Systems ◽

Non Destructive ◽

Maximum Likelihood Technique

AbstractSample sizes needed to measure population levels of the birch casebearer, Coleophora fuscedinella Zeller, and its damage to white birch, Betula papyrifera Marsh, were calculated for various degrees of confidence and assurance. Both a non-destructive and a destructive sampling plan are presented and a new method to classify the damage level of a stand. This method uses a maximum likelihood technique to estimate the proportion of trees of various damage classes.

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Power Spectrum Estiamtion II. Linear Maximum Likelihood

Data Analysis in Cosmology - Lecture Notes in Physics ◽

10.1007/978-3-540-44767-2_13 ◽

2008 ◽

pp. 433-456 ◽

Cited By ~ 1

Author(s):

A.J.S. Hamilton

Keyword(s):

Maximum Likelihood ◽

Power Spectrum

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The Very Small Array: Observations and Latest Results

Symposium - International Astronomical Union ◽

10.1017/s0074180900196512 ◽

2005 ◽

Vol 216 ◽

pp. 67-74

Author(s):

Anže Slosar ◽

Clive Dickinson

Keyword(s):

Power Spectrum ◽

Large Range ◽

Cosmological Parameters ◽

Low Noise ◽

Small Array

The Very Small Array (VSA) is a unique interferometric telescope operating at 33 GHz at Tenerife. It has the ability to measure fluctuations in the CMB over a large range of angular scales by means of three main array configurations: compact, extended and super-extended. These angular scales correspond to the multipole range ℓ = 150 —2500. Here we present new results from further observations of the extended array (February 2002 - June 2003). We cover ℓ-values up to ℓ ∼ 1600, thus doubling the ℓ-range of WMAP. The resulting power spectrum in the ℓ-range 800 – 1600 has very low noise coupled with good ℓ-resolution (Δℓ ∼ 80). Furthermore, the use of independently tracking aerials along with the dedicated source subtraction baseline allows unprecedented control of systematics. The latter is essential, since discrete sources are the dominant foreground at these angular scales. These measurements over larger ℓ-ranges are important in confirming the present cosmological paradigm and breaking degeneracies in the extraction of cosmological parameters.

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