CMB Observations: improvements of the performance of correlation radiometers by signal modulation and synchronous detection

Observation of the fine structures (anisotropies, polarization, spectral distortions) of the Cosmic Microwave Background (CMB) is hampered by instabilities, 1/f noise and asymmetries of the radiometers used to carry on the measurements. Addition of modulation and synchronous detection allows to increase the overall stability and the noise rejection of the radiometers used for CMB studies. In this paper we discuss the advantages this technique has when we try to detect CMB polarization. The behaviour of a two channel correlation receiver to which phase modulation and synchronous detection have been added is examined. Practical formulae for evaluating the improvements are presented.Comment: 18 pages, 3 figures, New Astronomy accepte

Idiomatic MWEs and Machine Translation. A Retrieval and Representation Model: the AraMWE Project

A preliminary implementation of AraMWE, a hybrid project that includes a statistical component and a CCG symbolic component to extract and treat MWEs and idioms in Arabic and English parallel texts is resented, together with a general sketch of the system, a thorough description of the statistical component and a proof of concept of the CCG componen