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SpaceFibre is a new technology for use onboard spacecraft that provides point-to-point and networked interconnections at 3.125 Gbits/s in flight qualified technology. SpaceFibre is an European Space Agency (ESA) initiative and will substitute the ubiquitous SpaceWire for high speed applications in space. FAPEC is a lossless data compression algorithm that typically offers better ratios than the CCSDS 121.0 Lossless Data Compression Recommendation on realistic data sets. FAPEC was designed for space communications, where requirements are very strong in terms of energy consumption and efficiency. In this project we have demonstrated that FAPEC can be easily integrated on top of SpaceFibre to reduce the amount of information that the spacecraft network has to deal with. The integration of FAPEC with SpaceFibre has successfully been validated in a representative FPGA platform. In the developed design FAPEC operated at ̃12 Msamples/s (̃200 Mbit/s) using a Xilinx Spartan-6 but it is expected to reach Gbit/s speeds with some additional work. The speed of the algorithm has been improved by a factor 6 while the resource usage remains low, around 2% of a Xilinx Virtex-5QV or a Microsemi RTG4. The combination of these two technologies can help to reduce the large amounts of data generated by some satellite instruments in a transparent way, without the need of user intervention, and to provide a solution to the increasing data volumes in spacecrafts. Consequently the combination of FAPEC with SpaceFibre can help to save mass, power consumption and reduce system complexity.

En noviembre de 2021 se cumplen 5 años del proceso de paz con las Farc. Esta es la primera versión crítica que se publica de lo que sucedió en La Habana. Documentos y conversaciones inéditas develan lo que no se conoce de la negociación. General (R) Jorge Enrique Mora Rangel GENERAL (R) JORGE ENRIQUE MORA Cúcuta, Norte de Santander, 1945. Se graduó como oficial del Ejército en diciembre de 1964. Inició su recorrido por todos los rincones del país, ocupando los cargos propios de la carrera militar. Alcanzó todos los grados hasta llegar al de general full de la república. Ocupó los cargos de comandante del Ejército y de las Fuerzas Militares. Obtuvo el grado honoris causa de la Universidad Sergio Arboleda. Realizó cursos militares en el Ejército de Estados Unidos y fue asesor en el Colegio Interamericano de Defensa en Washington. Tras su retiro del servicio activo fue designado embajador en Corea del Sur y Filipinas, asesor de seguridad en la gobernación de Cundinamarca e integrante del equipo negociador en el proceso de La Habana, donde permaneció desde el comienzo hasta el final.

Satellite data compression is very important for scientific missions, which often send large amounts of data during operations. Modern examples are Euclid, Solar Orbiter and the several Earth observation missions. However, for each mission and type of data the optimum solution can be different. Here we focus on compression of simulated images following the design specifications of the Euclid and Solar Orbiter missions, and on real images from NOAA and Eumetsat Earth Observation missions. We aim to achieve the best solution for the compression of these images, mainly regarding compression ratio, but also paying attention to the compression time - that is, trying to minimize the onboard processing requirements. Data compression research at the Institute for Space Studies of Catalonia (IEEC) has led to new algorithms that in some cases perform better than the consolidated standards of the CCSDS (Consultative Committee for Space Data Systems). The so-called Fully Adaptive Prediction Error Coder (FAPEC) is a new entropy-coding algorithm for data compression that provides an excellent coding efficiency even when large fractions of outliers are present in the data. It competes with the CCSDS 121.0 recommendation. On the other hand, the CCSDS 122.0 recommendation for image compression, based on the Discrete Wavelet Transform (DWT), can be used to produce both lossy and lossless compression. Previous studies have combined FAPEC with the 122.0 standard by compressing non-scaled DC and AC coefficients from the DWT stage, allowing FAPEC to achieve better compression ratios than the standard bit-plane encoder. The result, called DWTFAPEC, was able to work with FITS and raw images, both lossless and lossy. In this work we modify DWTFAPEC to differentially code the DC coefficients, further improving the performance - up to 10% in the lossy case. DWTFAPEC has been tested on a variety of realistic images (from Euclid, Solar Orbiter and Earth observation missions) to evaluate its performance and to demonstrate its eventual applicability to any space mission. For each of the cases studied here we show which is the optimum data compression solution among FAPEC, DWTFAPEC, CCSDS 121.0 and 122.0, both for lossless and lossy (where applicable), and for different options of the compressors. In all cases we consider both compression ratios and computing times. In some cases, due to the lack of capability to work with colour images we partitioned the images in sub-streams - one for each of the colour bands. This approach makes possible to use DWTFAPEC and FAPEC for colour images.

Plasma metal deposition (PMD®) is a promising and economical direct energy deposition technique for metal additive manufacturing based on plasma as an energy source. This process allows the use of powder, wire, or both combined as feedstock material to create near-net-shape large size components (i.e., >1 m) with high-deposition rates (i.e., 10 kg/h). Among the already PMD® processed materials stand out high-temperature resistance nickel-based alloys, diverse steels and stainless steels commonly used in the industry, titanium alloys for the aerospace field, and lightweight alloys. Furthermore, the use of powder as feedstock also allows to produce metal matrix composites reinforced with a wide range of materials. This chapter presents the characteristics of the PMD® technology, the welding parameters affecting additive manufacturing, examples of different fabricated materials, as well as the challenges and developments of the rising PMD® technology.

Herein we addressed a study to determine the enhancement factor (EF) of the Raman signal reached by composite films with two main components, Ag nanoparticles and SiO2 spheres. The study involves the synthesis, structural composition and optical response by using experimental techniques and theoretical-numerical modeling. A colloid with single NPs and agglomerates of them, with a tannic acid layer on its surface, was produced. Separately, porous SiO2 spheres were obtained. A mixture of both, Ag NPs and SiO2 particles was used to produce the films by solvent evaporation method. It is shown that single or agglomerated Ag NPs are preferentially located at the interstices of the SiO2 spheres. Using discrete dipole approximation, the SERS EF has been estimated considering the agglomeration and tannic acid layer. Both, the dielectric spheres and tannic acid layer diminish the electric field intensity and therefore the SERS EF. When a Ag NP with/without a dielectric shell is touching a SiO2 sphere, the EF is as high as 1 × 103, the zones where this value is reached are smaller when the dielectric layer is present. With a cluster of 3 nude Ag NPs surrounded by SiO2 spheres an EF of 2.4 × 103 is obtained.