Improving synthetic aperture image by image compounding in beamforming process

In this work, signal processing techniques are used to improve the quality of image based on multi-element synthetic aperture techniques. Using several apodization functions to obtain different side lobes distribution, a polarity function and a threshold criterium are used to develop an image compounding technique. The spatial diversity is increased using an additional array, which generates complementary information about the defects, improving the results of the proposed algorithm and producing high resolution and contrast images. The inspection of isotropic plate-like structures using linear arrays and Lamb waves is presented. Experimental results are shown for a 1-mm-thick isotropic aluminum plate with artificial defects using linear arrays formed by 30 piezoelectric elements, with the low dispersion symmetric mode S0 at the frequency of 330 kHz. © 2011 American Institute of Physics.

El mercado de trabajo bajo el nuevo régimen económico en Argentina

Incluye Bibliografía

Distribución del ingreso en la Argentina

Incluye Bibliografía

La distribución del ingreso en Argentina, 1974-2000

Incluye Bibliografía

Income distribution in Argentina, 1974-2000

Includes bibliography

Carta de Valdés Rodríguez de la Delegación de Cuba al Dr. Luis machado y Ortega Presidente de la II Sesión de la Comisión Económica para América Latina

Solicita la inclusión en la Agenda de la Conferencia del tema "Turismo"

Letter of Valdés Rodriguez President of the Cuban Delegation to Dr. Luis Machado y Ortega President of the Second Session of the Economic Commission for Latin America

Request the inclusion into the Agenda of the Conference of the item "Turismo"

Carta de Alberto Baltra C. Presidente de la Delegación de Chile al Dr. Luis Machado, Presidente de la Comisión Económica para América Latina

Sugiere introducir algunas modificaciones al Reglamento para lograr una mayor eficiencia en la labor de la Comisión

Letter of Alberto Baltra C. President of the Delegation of Chile to Dr. Luis Machado, Chairman of the Economic Commission for Latin America

Sugest introduce certain amendments in the Rules of Procedure, in order to make the work of the Commission more efficient