Impacts of Radar Echoes on Internal Calibration Signals in the TerraSAR-X Instrument

For calibrating and monitoring the required radiometric stability, the radar instrument of TerraSAR-X features an internal calibration facility coupling into an additional port of the TRMs. Calibration pulses are routed through the front-end to characterise critical elements and parameters of the transmit (TX) and receive (RX) path. Changes in the signal path appear due to thermal effects, degradation, or extreme conditions in space. Especially the front-end TRMs controlling the phased array antenna are of crucial significance for the instrument reliability. There are many indications that the interference of the RX-Calibration signals is caused by an echo from a transmitted TerraSAR-X chirp pulse of the same data take. As consequently implemented in the TerraSAR-X system, different approaches solve these effects of signal interference. In orbit, the commanding sequence can be optimised for avoiding interference. At processing level, averaging techniques minimise the noise effects inside the calibration signals. This paper presents the effects of the radar echoes on the whole internal calibration process and how they can be detected and minimised

First order transitions by conduction calorimetry: Application to deuterated potassium dihydrogen phosphate ferroelastic crystal under uniaxial pressure

The specific heat c and the heat power W exchanged by a Deuterated Potassium Dihydrogen Phosphate ferroelectric-ferroelastic crystal have been measured simultaneously for both decreasing and increasing temperature at a low constant rate (0.06 K/h) between 175 and 240 K. The measurements were carried out under controlled uniaxial stresses of 0.3 and 4.5±0.1 bar applied to face (110). At Tt=207.9 K, a first order transition is produced with anomalous specific heat behavior in the interval where the transition heat appears. This anomalous behavior is explained in terms of the temperature variation of the heat power during the transition. During cooling, the transition occurs with coexistence of phases, while during heating it seems that metastable states are reached. Excluding data affected by the transition heat, the specific heat behavior agrees with the predictions of a 2-4-6 Landau potential in the range of 4–15 K below Tt while logarithmic behavior is obtained in the range from Tt to 1 K below Tt. Data obtained under 0.3 and 4.5 bar uniaxial stresses exhibit the same behavior.Dirección General de Investigación Científica y Técnica. Gobierno de España-PB91-60

Polyimide (PI) films by chemical vapor deposition (CVD): Novel design, experiments and characterization

Polyimide (PI) has been deposited by chemical vapor deposition (CVD) under vacuum over the past 20 years. In the early nineties, studies, experiences and characterization were mostly studied as depositions from the co-evaporation of the dianhydride and diamine monomers. Later on, several studies about its different applications due to its interesting mechanical and electrical properties enhanced its development. Nowadays, not many researches around PI deposition are being carried. This paper presents a PI film deposition research project with an original CVD process design. The deposition is performed under ambient conditions (atmospheric pressure) through a gas flux vector. Design of apparatus, deposition conditions and preliminary characterizations (IR, SEM and surface analyses) are discussed

Arturo Pavón, recorrido diacrónico y análisis musicológico

Esta comunicación es la síntesis del análisis musicológico del corpus musical de uno de los máximos representantes de la “generación canónica” del piano flamenco: Arturo Pavón. El objetivo principal es realizar un recorrido diacrónico analizando sus grabaciones, ya que destapa por qué se convertiría prácticamente en la única referencia para la generación posterior, destacando etapas y obras claves, como las colaboraciones con sus familiares –Pepe Pinto, Luisa Ortega y Manolo Caracol–, la Suite Flamenca y otros trabajos posteriores. De esta manera, se presentan las bondades y problemáticas de su obra, para que futuras investigaciones puedan resolver cuestiones tan primordiales como una cronología exhaustiva.This communication is the synthesis of Arturo Pavon’s work musicological analysis, one of the leading representatives of the flamenco pianists “canonical generation”. His recordings diachronic tour uncover why he would practically become the only reference for the following generation, emphasizing stages and key works, as the collaborations with his relatives –Pepe Pinto, Luisa Ortega and Manolo Caracol–, Suite Flamenca and later works. The paper aim is to present his work goodness and problems, so future researchers can resolve some of the key issues such as an exhaustive chronology

La cátedra de Escoto en México, siglo XVIII

Ponencia en las V Jornadas sobre la presencia universitaria española en América: universidad y colegios universitarios en la época postcolonial (1760-1830). Alcalá de Henares, Noviembre de 1991

Historical translation in the XVth century between Italy and Castile. Notes on the Decembrian version of the First Punic War and its Spanish translation

En el presente trabajo mostramos un panorama de conjunto del romanceamiento, conservado en dos manuscritos, que Pier Candido Decembrio realizó en Milán hacia 1438 de la versión latina bruniana de Polibio Commentarii tres de Primo Bello Punico, así como de la traducción castellana que se realizó a partir de uno de ellos, transmitida también en dos testimonios. Ponemos en relación estos cuatro manuscritos por primera vez y sentamos las bases para un futuro análisis filológico y traductológico más amplio.In this paper we present an overall view of the vernacular version by Pier Candido Decembrio, witnessed throught two manuscripts, that the humanist accomplished in Milan around 1438 following the latin tranlation of Polybe’s Commentarii tres de Primo Bello Punico than Leonardo Bruni had prepared some years earlier. We also show the manuscript tradition of this text in castillian, also witnessed in two manuscripts. We relate these four codex with each other for the first time and we settle the basements for a wider future philological and translational study

Use of idempotent functions in the aggregation of different filters for noise removal

The majority of existing denoising algorithms obtain good results for a specific noise model, and when it is known previously. Nonetheless, there is a lack in denoising algorithms that can deal with any unknown noisy images. Therefore, in this paper, we study the use of aggregation functions for denoising purposes, where the noise model is not necessary known in advance; and how these functions affect the visual and quantitative results of the resultant images