Automatic human face detection for content-based image annotation

In this paper, an automatic human face detection approach using colour analysis is applied for content-based image annotation. In the face detection, the probable face region is detected by adaptive boosting algorithm, and then combined with a colour filtering classifier to enhance the accuracy in face detection. The initial experimental benchmark shows the proposed scheme can be efficiently applied for image annotation with higher fidelity

Feature extraction for speech and music discrimination

Driven by the demand of information retrieval, video editing and human-computer interface, in this paper we propose a novel spectral feature for music and speech discrimination. This scheme attempts to simulate a biological model using the averaged cepstrum, where human perception tends to pick up the areas of large cepstral changes. The cepstrum data that is away from the mean value will be exponentially reduced in magnitude. We conduct experiments of music/speech discrimination by comparing the performance of the proposed feature with that of previously proposed features in classification. The dynamic time warping based classification verifies that the proposed feature has the best quality of music/speech classification in the test database

Magnetic Field Pinning of a Dynamic Electron-Spin-Resonance Line in a GaAs/AlGaAs Heterostructure

Electrically detected electron spin resonance (ESR) is used to study the hyperfine interaction of the two-dimensional electrons and the nuclei of the host lattice in a GaAs/AlGaAs heterostructure. Under the microwave and radio- frequency double excitations, we have observed that the ESR line can be pinned in a very narrow range of magnetic field - in the vicinity of the nuclear magnetic resonance (NMR) of the nuclei of the GaAs crystal. Our observations suggest that this pinning effect is the result of a competition process between the ESR induced dynamic nuclear polarization and the NMR induced depolarization.Comment: 4 pages, 4 figure

Reversibility Checking for Markov Chains

In this paper, we present reversibility preserving operations on Markov chain transition matrices. Simple row and column operations allow us to create new reversible transition matrices and yield an easy method for checking a Markov chain for reversibility

Analyticity of the Susceptibility Function for Unimodal Markovian Maps of the Interval

In a previous note [Ru] the susceptibility function was analyzed for some examples of maps of the interval. The purpose of the present note is to give a concise treatment of the general unimodal Markovian case (assuming $f$ real analytic). We hope that it will similarly be possible to analyze maps satisfying the Collet-Eckmann condition. Eventually, as explained in [Ru], application of a theorem of Whitney [Wh] should prove differentiability of the map $f\mapsto\rho_f$ restricted to a suitable set.Comment: 8 page

A simple and efficient all-optical production of spinor condensates

We present a simple and optimal experimental scheme for an all-optical production of a sodium spinor Bose-Einstein condensate (BEC). With this scheme, we demonstrate that the number of atoms in a pure BEC can be greatly boosted by a factor of 5 in a simple setup that includes a single-beam optical trap or a crossed optical trap. This optimal scheme avoids technical challenges associated with some all-optical BEC methods, and can be applied to other optically trappable atomic species. In addition, we find a good agreement between our theoretical model and data. The upper limit for the efficiency of evaporative cooling in all-optical BEC approaches is also discussed.Comment: 5 pages, 5 figure