A new approach for Synthetic Aperture Radar (SAR) based sea ice image segmentation for the retrieval of floe size distribution (FSD) is proposed. This method consists of three stages. The first stage involves the pre-processing of the SAR image to reduce the speckle noise in the image by median filtering. The second stage involves an initial segmentation of the image using the Watershed transform. The third stage involves a region merging process based on the difference function of the mean intensity of adjacent regions. Adjacent regions are defined by the region adjacency graph based on a minimum distance of 1 pixel between two adjacent regions. A threshold value is usually set for the merging process, if the difference in mean intensity of adjacent regions is less than the threshold, the adjacent regions will be merged. Experimental results have shown the efficacy of the proposed method in effective segmentation of SAR ice images.

This paper presents an automatic detection of Dysarthria, a motor speech disorder, using extended speech features called Centroid Formants. Centroid Formants are the weighted averages of the formants extracted from a speech signal. This involves extraction of the first four formants of a speech signal and averaging their weighted values. The weights are determined by the peak energies of the bands of frequency resonance, formants. The resulting weighted averages are called the Centroid Formants. In our proposed methodology, these centroid formants are used to automatically detect Dysarthric speech using neural network classification technique. The experimental results recorded after testing this algorithm are presented. The experimental data consists of 200 speech samples from 10 Dysarthric speakers and 200 speech samples from 10 age-matched healthy speakers. The experimental results show a high performance using neural networks classification. A possible future research related to this work is the use of these extended features in speaker identification and recognition of disordered speech.

The results highlight the potential for improvement of stress production in speakers with motor speech disorders. The fact that individual parameter manipulation is as effective as combining them will facilitate the therapeutic process considerably, as will the result that amplification at lower levels than seen in typical speakers is sufficient. The difference in results across utterance sets highlights the need to investigate the underlying error pattern in order to select the most effective compensatory strategy for clients.

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Marking stress is important in conveying meaning and drawing listener's attention to specific parts of a message. Extensive research has shown that healthy speakers mark stress using three main acoustic cues; pitch, intensity, and duration. The relationship between acoustic and perception cues is vital in the development of a computer-based tool that aids the therapists in providing effective treatment to people with Dysarthria. It is, therefore, important to investigate the acoustic cues deficiency in dysarthric speech and the potential compensatory techniques needed for effective treatment. In this paper, the relationship between acoustic and perceptive cues in dysarthric speech are investigated. This is achieved by modifying stress marked sentences from 10 speakers with Ataxic dysarthria. Each speaker produced 30 sentences using the 10 SubjectVerb-Object-Adverbial (SVOA) structured sentences across three stress conditions. These stress conditions are stress on the initial (S), medial (O) and final (A) target words respectively. To effectively measure the deficiencies in Dysarthria speech, the acoustic features (pitch, intensity, and duration) are modified incrementally. The paper presents the techniques involved in the modification of these acoustic features. The effects of these modifications are analysed based on steps of 25% increments in pitch, intensity and duration. For robustness and validation, 50 untrained listeners participated in the listening experiment. The results and the relationship between acoustic modifications (what is measured) and perception (what is heard) in Dysarthric speech are discussed.