Blind separation of speech with a switched sparsity and temporal criteria

A blind signal separation algorithm (SCAtemp) that exploits both the sparse time-frequency representation and temporal structure of speech is proposed. SCAtemp compares each speech signal\u27s adherence to the sparsity and temporal criteria, before switching to the most appropriate criteria to estimate each signal. This algorithm is shown to improve the real time separation performance of conventional BSS algorithms exclusively exploiting either the temporal structure, sparsity or statistical independence of signals. The improvement of SCAtemp over conventional BSS algorithms can be attributed to the use of additional a priori knowledge of speech in the temporal short term

Coagulation kinetics beyond mean field theory using an optimised Poisson representation

Binary particle coagulation can be modelled as the repeated random process of the combination of two particles to form a third. The kinetics can be represented by population rate equations based on a mean field assumption, according to which the rate of aggregation is taken to be proportional to the product of the mean populations of the two participants. This can be a poor approximation when the mean populations are small. However, using the Poisson representation it is possible to derive a set of rate equations that go beyond mean field theory, describing pseudo-populations that are continuous, noisy and complex, but where averaging over the noise and initial conditions gives the mean of the physical population. Such an approach is explored for the simple case of a size-independent rate of coagulation between particles. Analytical results are compared with numerical computations and with results derived by other means. In the numerical work we encounter instabilities that can be eliminated using a suitable 'gauge' transformation of the problem [P. D. Drummond, Eur. Phys. J. B38, 617 (2004)] which we show to be equivalent to the application of the Cameron-Martin-Girsanov formula describing a shift in a probability measure. The cost of such a procedure is to introduce additional statistical noise into the numerical results, but we identify an optimised gauge transformation where this difficulty is minimal for the main properties of interest. For more complicated systems, such an approach is likely to be computationally cheaper than Monte Carlo simulation

Educational History Resources at Yukon Archives

Résumé Le mandat des Archives du Yukon est d’acquérir, préserver et rendre accessibles des fonds d’une importance pérenne pour la compréhension de l’histoire et du développement du Yukon et de fournir de la documentation sur ses divers peuples, cultures et sociétés. Les Archives font l’acquisition de documents publics en provenance du gouvernement et des communautés du Yukon, ainsi que des archives privées léguées par des individus, des corporations, des organisations, des groupes religieux, etc. Les Archives du Yukon possèdent également une grande bibliothèque pour la recherche contenant des publications en histoire, en ethnographie, en sciences et en sociologie ainsi que des rapports portant spécifiquement sur le Yukon et ses peuples.   Abstract The mandate of Yukon Archives is to acquire, preserve, and make accessible records of lasting importance to understanding the history and development of Yukon and documenting its diverse peoples, cultures, and society. The archives acquires public records from its sponsoring agency (the Yukon government) and Yukon communities and private records from individuals, corporations, societies, religious groups, etc. Yukon Archives also includes a large research library of historical, ethnographic, scientific, and sociological publications and reports of relevance to the study of Yukon and its peoples.

Hybrid Sequencing of Uncompressed and Compressed 3D Stereoscopic Video: A Preliminary Quality Evaluation

The use of 3D stereoscopic technology with high quality videos can provide visual entertainment to viewers. However, the bandwidth of typical communication channels cannot transmit uncompressed 3D videos, resulting in the need for video quality compression. This paper presents a series of preliminary studies to investigate the subjective perception of uncompressed and compressed video sequences, and proposes the ‘hybrid’ sequencing of uncompressed and compressed content in a single stereoscopic 3D video as an alternative approach for limited bandwidth transmission. However, the hybrid uncompressed/compressed sequencing of stereoscopic 3D video may affect the correlation between the left and right views of the stereoscopic videos required for depth perception, potentially leading to lower Quality of Experience (QoE) of viewers. This paper therefore investigates both the objective and subjective quality evaluation of the proposed hybrid sequencing of stereoscopic video sequences. Initial investigations into objective metrics to measure the difference in quality of the two stereoscopic views due to the proposed hybrid sequencing of uncompressed and compressed videos were also conducted

A study on sound source apparent shape and wideness

Proceedings of the 9th International Conference on Auditory Display (ICAD), Boston, MA, July 7-9, 2003.This work is intended as an initial investigation into the perception of wideness and shape of sound sources. A method that employs multiple uncorrelated point sources is used in order to form ``sound shapes''. Several experiments were carried out in which, after some initial training, subjects were asked to indentify the shapes that were being played. Results indicate that differences in vertical and horizontal source wideness are easily perceived and scenes that use broad sound sources to represent normally large sound objects are selected 70% of the time over point source versions. However, shape identification was found to be more ambiguous except for certain types of signals where results were above statistical probability. The work indicates that shape and wideness of sound sources could be effectively used as extra cues in virtual auditory displays and generally improve the realism of virtual 3D sound scenes. This work was performed as a Core Experiment within the MPEG Audio Subgroup with the intention of possible integration of source wideness into MPEG-4 AudioBIFS

Blind Separation of Speech with a Switched Sparsity and Temporal Criteria

A blind signal separation algorithm (SCAtemp) that exploits both the sparse time-frequency representation and temporal structure of speech is proposed. SCAtemp compares each speech signal\u27s adherence to the sparsity and temporal criteria, before switching to the most appropriate criteria to estimate each signal. This algorithm is shown to improve the real time separation performance of conventional BSS algorithms exclusively exploiting either the temporal structure, sparsity or statistical independence of signals. The improvement of SCAtemp over conventional BSS algorithms can be attributed to the use of additional a priori knowledge of speech in the temporal short term

Enhancing Multimedia Search Using Human Motion

Over the last few years, there has been an increase in the number of multimedia-enabled devices (e.g. cameras, smartphones, etc.) and that has led to a vast quantity of multimedia content being shared on the Internet. For example, in 2010 thirteen million hours of video uploaded to YouTube (http://www.youtube.com). To usefully navigate this vast amount of information, users currently rely on search engines, social networks and dedicated multimedia websites (such as YouTube) to find relevant content. Efficient search of large collections of multimedia requires metadata that is human-meaningful, but currently multimedia sites generally utilize metadata derived from user-entered tags and descriptions. These are often vague, ambiguous or left blank, which makes search for video content unreliable or misleading. Furthermore, a large majority of videos contain people, and consequently, human movement, which is often not described in the user entered metadata