Biometric-based techniques have recently emerged as a trustworthy and effective approach of user authentication; however, unlike conventional authentication methods such as passwords and tokens, if an enrolled biometric template is compromised, usually it cannot be revoked or re-issued. In this paper, four naive cancelable techniques, namely, shifting, password-dependent shifting, XOR and adding, for a bimodal biometric cryptosystem are presented. The proposed cancelable techniques are designed to be embedded into any bimodal biometric cryptosystem. The bimodal biometric cryptosystem uses speech and electrocardiogram signals as biometric information. The biometric cryptosystem implements an error-correction layer using the Hadamard code. The performance of the four cancelable techniques is assessed using ECG signals from MIT-BIH database and speech signals from a speech database created for testing purposes. The results show that the best performance in terms of FAR and FRR metrics is achieved with XOR and adding techniques

The dynamics of a coupled system comprising a two-level atom and cavity field assisted by a continuous external classical field (driving Jaynes-Cummings model) is studied. When the initial field is prepared in a coherent state, the dynamics strongly depends on the algebraic sum of both fields. If this sum is zero (the compensative case) in the system, only the vacuum Rabi oscillations occur. The results with dissipation and external field detuning from the cavity field are also discussed.

Estudiamos la dinámica de un sistema acoplado de un átomo de dos niveles y un campo electromagnético quántico de cavidad asistidos por un campo electromagnético clásico externo continuo (modelo Jaynes-Cummings guiado). Cuando el campo de la cavidad inicialmente es preparado en un estado coherente, la dinámica depende fuertemente de la suma algebraica de ambos campos. Si este suma es cero (caso compensativo) en el sistema solo ocurren las oscilaciones de Rabi de vacío. También discutimos los resultados con disipación y desintonizacion del campo externo con respecto al campo de la cavidad.

Electro-rotation can be used to determine the dielectric properties of cells, as well as to observe dynamic changes in both dielectric and morphological properties. Suspended biological cells and particles respond to alternating-field polarization by moving, deforming or rotating. While in linearly polarized alternating fields the particles are oriented along their axis of highest polarizability, in circularly polarized fields the axis of lowest polarizability aligns perpendicular to the plane of field rotation. Ellipsoidal models for cells are frequently applied, which include, beside sphere-shaped cells, also the limiting cases of rods and disks. Human erythrocyte cells, due to their particular shape, hardly resemble an ellipsoid. The additional effect of rouleaux formation with different numbers of aggregations suggests a model of circular cylinders of variable length. In the present study, the induced dipole moment of short cylinders was calculated and applied to rouleaux of human erythrocytes, which move freely in a suspending conductive medium under the effect of a rotating external field. Electro-rotation torque spectra are calculated for such aggregations of different length. Both the maximum rotation speeds and the peak frequencies of the torque are found to depend clearly on the size of the rouleaux. While the rotation speed grows with rouleaux length, the field frequency nup is lowest for the largest cell aggregations where the torque shows a maximum.