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The ISDB-T multiplex frame pattern explained
Get PDFTrabajo presentado en IEEE URUCON, Montevideo, Uruguay, 23-25 oct., 2017ISDB-T defines the so-called Broadcast Transport Stream, an MPEG transport stream adapted to carry hierarchical information. This BTS is created in the transmission side, but it has to be perfectly recovered in reception. To that end there is an algorithm defined in the standard which we found not clear regarding the implementation. We also found the bibliography regarding this algorithm was poor. After our experience implementing gr-isdbt, the first open, free and software-based ISDB-T receiver, fully implemented in GNU Radio, we were able to understand this algorithm and decided to describe it step by step from the implementation point of vie
A low cost system for self measurements of power consumption in field programmable gate arrays
Get PDFThis paper presents a specific system to measure power consumption in FPGAs. It is based on a current-frequency conversion block. This tool allows an application running inside the FPGA to know its own consumption in real time. The proposed system includes a small external circuit that performs current-to-frequency conversion and an associated VHDL core designed to register the power consumption inside the FPGA. The external circuit is built with off-the-shelf low-cost components and has low power consumption, the VHDL core uses very few on-chip resources. The complete system has an error lower than 1% in the FPGA power consumption measurement. As it can be triggered by internal complex conditions, it makes it possible to obtain detailed power consumption profiles of FPGA designs using a very simple procedure
Reducing anomaly detection in images to detection in noise
Get PDFTrabajo presentado al 25th IEEE International Conference on Image Processing (ICIP)Anomaly detectors address the difficult problem of detecting automatically exceptions in an arbitrary background image. Detection methods have been proposed by the thousands because each problem requires a different background model. By analyzing the existing approaches, we show that the problem can be reduced to detecting anomalies in residual images (extracted from the target image) in which noise and anomalies prevail. Hence, the general and impossible background modeling problem is replaced by simpler noise modeling, and allows the calculation of rigorous thresholds based on the a contrario detection theory. Our approach is therefore unsupervised and works on arbitrary images
Calculation of the capacity value for wind generation in Uruguay
Get PDFTrabajo presentado a EEE PES TransmissionDistribution Conference and Exhibition, Latin America (TD-LA), Lima, Perú,18-21 set., 2018.Traditionally the Uruguayan electric system has been composed of thermal and hydroelectric generation. In the last decade a huge amount of wind and solar generation has been added into the system. This has lead in practice to a reduction of the amount of the thermal back up capacity required. In fact, several MW of thermal generation has recently been decommissioned. However, current regulation in Uruguay do not consider the contribution of wind or solar generation to firm capacity. The aim of this work is to establish an adequate methodology to estimate the contribution of the wind farms in Uruguay to the firm power capacity of the system. Finally, simulations with real data were made in R software in order to evaluate the amount of this constribution
Development of a multiple-scattering acoustic sensor for process monitoring: Application to monitoring milk coagulation
Get PDFTrabajo presentado al International Instrumentation and Measurement Technology Conference (I2MTC). Turin, Italia, 22-25 May 2017Diverse industrial processes can be monitored by tracking changes in a fluid media. Having inline nondestructive information about the state of the process permits to have optimal results at reasonable costs. The suitability of low-power-ultrasound techniques has been widely investigated. However, sometimes this techniques have a poor signal-to-noise ratio or excessive sensitivity to temperature changes. In the present work, multiple-scattering of an ultrasonic signal is generated to enhancing the process-tracing ability. A pulse-echo system is used. The acoustic signal travels through a rod array, which is immersed in the changing medium. Useful information is taken from the echoes correlation. As a test case, this system has been proved for tracing milk coagulation, which is necessary in the cheese-manufacturing proces
Investigación de parámetros químicos para evaluar frescura en caracol fino (Zidona dufresnei)
Get PDFPrimera experiencia de infección experimental de esturión siberiano (Acipencer baeri) con Streptococcus dysgalactiae
Get PDFVariabilidad diaria y estacional de la asamblea de peces juveniles del estuario del arroyo Pando (Canelones)
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