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The ocean surface radar is used for tsunami early warning systems. This radar can measure radial current velocity at every range and azimuth resolution cell in radar coverage. However, the measured velocity has measurement errors, which might make the approach of a tsunami unclear. In this paper, we propose a tsunami detection technique that reduces false alarms by estimating tsunami parameters statistically by maximum likelihood estimation. Multiple detection points of a tsunami exceeding the range and azimuth resolution are integrated assuming the arrival wave front. The validity of the proposed algorithm is confirmed through Sumatra earthquake tsunami simulations. Keywords-Radar, tsunami, detect, extended target, maximum likelihood

A new approach for multi-target tracking under grating lobe environment is presented. Ambiguous angle measurements are obtained by a wide-array antenna whose elements have a long interval. Angle measurements different from the true target angles are obtained because of the grating lobes; therefore, it is difficult to initialize and maintain target tracking accurately. In this paper, we propose a multi-dimensional multiple hypothesis tracking method using a Gaussian mixture model, which is an extension of multiple hypothesis tracking for multiple targets. The proposed method assumes distribution of angle measurement error including grating lobes as a Gaussian mixture model. From this assumption, combinations of measurements, tracks, and Gaussian components are generated as a three-dimensional (3-D) hypothesis. The algorithm finds multiple measurement-to-track-to-grating hypotheses from a 3-D association matrix efficiently. Simulations are performed to demonstrate the effectiveness of the proposed algorithms.

Simultaneous occurrence of bilateral axillary Paget's disease in a 61-year-old male with genital Paget's disease of 2 years' duration was presented. Invasive adenocarcimoma was found in the genital lesion. No regional lymph node metastases ware apparent. The lesions were excised in toto. There has been no recurrence 14 months later. Four previously reported cases of double or triple extramammary Paget's disease, together with two more cases were summarized. Generally, the axillary lesions were clinically insignificant, faintly erythematous patches and could hardly be identified without histological examination.