No abstract

A technique of image processing based on application of the Singular Spectrum Analysis (SSA) is discussed and illustrated on the problem of denoising the celebrated 'Lena' image corrupted with noise. Also, SSA-based distances between two images are introduced and suggested for a possible use in the face verification problem.

Abstract. We present a novel 3D facial feature location method based on the Spin Images registration technique. Three feature points are localized: the nose tip and the inner corners of the right and left eye. The points are found directly in the 3D mesh, allowing a previous normalization before the depth map calculation. This method is applied after a preprocess stage where the candidate points are selected measuring curvatures on the surface and applying clustering techniques. The system is tested on a 3D Face Database called FRAV3D with 105 people and a widely variety of acquisition conditions in order to test the method in a non-controlled environment. The success location rate is 99.5% in the case of the nose tip and 98% in the case of eyes, in frontal conditions. This rate is similar even if the conditions change allowing small rotations. Results in more extremely acquisition conditions are shown too. A complete study of the influence of the mesh resolution over the spin images quality and therefore over the face feature location rate is presented. The causes of the errors are discussed in detail.

The quality factor (Q) of different modes of self-actuated aluminium nitride beams operated in air and liquid media is analyzed applying different techniques. In air, both optical and electrical techniques are used. In the case of the optical approach, characterization is done with a laser Doppler vibrometer. The values for the Q factors are deduced straight forward from both the frequency spectrum and the transient response, while electrical impedance measurements need a more careful evaluation with two different fitting methods to obtain the Q factor of the vibration modes. In water, only optical measurements, more sensitive than the electrical measurements, could be used to determine the Q factor of selected modes. In addition, the results of finite element model analysis were compared to the experimental data, showing an excellent agreement regarding the modal shape and the resonance frequency of the microresonators.

No abstract