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1 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Title here Text here
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2 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Movement data from relevant species Movement data obtained for: Squirrel monkey Howler monkey Mountain tapir Lowland tapir White-lipped peccary Cattle White-tailed deer Cougar Red-knobbed hornbill Malay sun bear Tiger
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3 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Introduction Two parts Track-level discrimination of dismounts and animals Micro-Doppler algorithms for dismount/animal discrimination & species identification
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4 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Track-level Algorithms
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5 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Track-level Discrimination Algorithms Techniques we developed & presented earlier – Wavelet analysis of Euclidean distance from arbitrary starting point Seems to be very effective Normal vectors to path segments Derived from Gauss-Bonnet theorem
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6 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Track-level Discrimination Algorithms Techniques we presented earlier – MethodCriterionDismountAnimal on Home Range WaveletsWavelet coefficients for different scale factors Large values of scale factor predominate = little/no retracing of path segments Small values of scale factor predominate = frequent retracing of path segments Centroids of normal vectors Temporal evolution of centroid Centroid tends to track – or parallel – animal/dismount path Centroid independent from path, approaches quasi-stable point
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7 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Track-level Discrimination Algorithms Applied both techniques to Ft. Stewart data Dismounts moving along designated Domestic animals moving along pentagonal path or milling about in pens
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8 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Track-level Algorithms Loops in tracks (horse/rider combination) don’t alter correspondence with Gauss-Bonnet
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9 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Track-level Algorithms Wavelet analysis reveals small-scale structure due to the loops in the path
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10 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Track-level Algorithms Horse led point-to-point along a straight path produces characteristic picture Same result for dismount moving along designated path.
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11 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Track-level Algorithms Wavelet analysis reveals lack of any evidence of periodicity in straight path of horses being led from point-to-point
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12 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Track-level Discrimination Algorithms Drawback – discrimination based on wavelets or normal vector centroid requires relatively large number of data points. Time required may be too long for many tactical situations. Wanted an algorithm that takes advantage of unique properties of animals’ home range movements over very short time scales. Central place foraging (CPF) versus non-Central place foraging (non-CPF)
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13 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Non-CPF, with more-or-less complete sampling of home range
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14 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY CPF, with more-or-less complete sampling
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15 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY CPF, sampling different part of home range each day - note significant linearity in paths Note Levy flights!
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16 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Track-level Discrimination Algorithms We’re treading new ground here Most field biologists doing telemetry aren’t interested in animal movements at scales of relevance to our work Usual goal = assess home range dimensions Data usually recorded at intervals of tens of minutes, even hours or days. Self-similar (fractal) nature of animal movement lets us compensate for lack of extreme short time-scale data Lévy-type movement pattern at scales of tens of minutes, or hours will be Lévy-type at shorter time scales
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17 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Mean-square successive difference:Variance Ratio
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18 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Mean-square successive difference:Variance Ratio
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19 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Mean-square successive difference:Variance Ratio
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20 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY MSD:Variance Ratio for Home Range and Simulated Dismount Paths TTI_movie_1.avi TTI_movie_1.avi
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21 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY MSD:Variance Ratio for Home Range and Simulated Dismount Paths How do results of normal vector centroid, wavelet analysis, and MSD:Variance Ratio compare? Used data from: Deer (human-sized mammal) Dismounts moving along designated paths in Honduras
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22 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Deer 2, Dismount Path 5
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23 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Deer 6, Dismount Path 5
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24 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Deer 7 Dismount Path 5
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25 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Deer 5, Dismount Path 5
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26 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Micro-Doppler Results
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27 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY ‘Micro-Doppler ‘ Results here Data consist of iFFT ‘reconstituted’ raw returns from 9 range bins centered on Horse 26’s position. Don? Analyzed each 5-second frame ( n = 180 ) separately Results of preliminary wavelet analysis (Daubechies 4): horse26_full_doppler_wavelet_analysis_256.avi
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28 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY The ‘complexity’ of the wavelet coefficient matrix appears to be sensitive to the presence of a horse in a range bin, and the speed of the horse This makes sense…the faster the horse runs, the more the return signal will be affected by movement of head, neck, mane, appendages, and tail. Recall from the last QPR, I showed that the micro-Doppler signal’s rolloff depended on horse speed. More & larger micro-Doppler peaks in the signal more complex signal entropy Possible species-specific features?
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29 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Analysis of ‘raw’ signals Computed wavelet entropy for each frame, using 4 different values for the maximum scale factor Determined Doppler value ( m/s ) for each frame Wavelet entropy results were binned by the absolute value of the Doppler m/s
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30 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Wavelet Entropy vs. Absolute Doppler
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31 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Wavelet Entropy vs. Absolute Doppler
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32 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Wavelet Entropy vs. Absolute Doppler
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33 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Wavelet Entropy vs. Absolute Doppler
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34 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Analysis of ‘raw’ signals Next, concatenated the 180 5-second chips to create a single 900-second time series of return signal amplitudes Wavelet analysis conducted using different wavelets Wavelets differ in Symmetry ‘look at’ data somewhat differently Width differential sensitivity to fine-scale features of the data
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35 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Analysis Using Haar Wavelet
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36 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Analysis Using Daubechies 4 Wavelet
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37 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Analysis Using Daubechies 10 Wavelet
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38 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Analysis Using Ricker (Mexican Hat) Wavelet
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39 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Analysis Using Symlets 2 Wavelet
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40 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Analysis Using Symlets 8 Wavelet
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41 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Analysis Using Coiflet 1 Wavelet
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42 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Analysis Using Coiflet 5 Wavelet
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43 Technology Service Corporation / California Operations FOR OFFICIAL USE ONLY Conclusion Next steps Work out statistical properties of the Mean-square successive difference:Variance Ratio, when applied to Lévy processes Evaluate different wavelets for their utility under different circumstances (terrain, target type, radar type) May develop new wavelet(s) to target specific features of data Time series analysis of raw radar returns using Standard approaches, e.g. ARIMA Nonlinear dynamics & chaos theory Lyapunov exponents & correlation dimension Various entropy measures Implement a Naïve Bayes Classifier using output from track-level and micro-Doppler algorithms
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