[Lettre autographe signée de Giuseppe Verdi adressée à Du Locle, Gênes, 25 décembre 1871]

Comprend aussi une phrase et signature autographe de Teresa Stolz

[Portrait du sprinter Emile] Ali Khan [vainqueur du 100 m des championnats de France d'athlétisme, le 18/7/20, stade Pershing] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 60110

[Portrait du sprinter Emile] Ali Khan [vainqueur du 100 m des championnats de France d'athlétisme, le 18/7/20, stade Pershing] : [photographie de presse] / [Agence Rol]

Référence bibliographique : Rol, 60111

Concordantiarum ss. scripturae manuale

UANL

Proposed design for an ultrasonic optical force-feedback microphone

We discuss a novel approach that would lead to the development of an ultrasonic optical force-feedback measurement microphone.

Performance limitations of piezoelectric and force feedback electrostatic transducers in different applications

Current limitations in piezoelectric and electrostatic transducers are discussed. A force-feedback electrostatic transducer capable of operating at bandwidths up to 20 kHz is described. Advantages of the proposed design are a linearised operation which simplifies the feedback control aspects and robustness of the performance characteristics to environmental perturbations. Applications in nanotechnology, optical sciences and acoustics are discussed.

Propagation of errors from a null balance terahertz reflectometer to a sample's relative water content

The THz water content index of a sample is defined and advantages in using such metric in estimating a sample's relative water content are discussed. The errors from reflectance measurements performed at two different THz frequencies using a quasi-optical null-balance reflectometer are propagated to the errors in estimating the sample water content index.