547 research outputs found

    Event Recognition Using Signal Spectrograms in Long Pulse Experiments

    Get PDF
    As discharge duration increases, real-time complex analysis of the signal becomes more important. In this context, data acquisition and processing systems must provide models for designing experiments which use event oriented plasma control. One example of advanced data analysis is signal classification. The off-line statistical analysis of a large number of discharges provides information to develop algorithms for the determination of the plasma parameters from measurements of magnetohydrodinamic waves, for example, to detect density fluctuations induced by the Alfvén cascades using morphological patterns. The need to apply different algorithms to the signals and to address different processing algorithms using the previous results necessitates the use of an event-based experiment. The Intelligent Test and Measurement System platform is an example of architecture designed to implement distributed data acquisition and real-time processing systems. The processing algorithm sequence is modeled using an event-based paradigm. The adaptive capacity of this model is based on the logic defined by the use of state machines in SCXML. The Intelligent Test and Measurement System platform mixes a local multiprocessing model with a distributed deployment of services based on Jini

    Data reduction in the ITMS system through a data acquisition model with self-adaptive sampling rate

    Get PDF
    Long pulse or steady state operation of fusion experiments require data acquisition and processing systems that reduce the volume of data involved. The availability of self-adaptive sampling rate systems and the use of real-time lossless data compression techniques can help solve these problems. The former is important for continuous adaptation of sampling frequency for experimental requirements. The latter allows the maintenance of continuous digitization under limited memory conditions. This can be achieved by permanent transmission of compressed data to other systems. The compacted transfer ensures the use of minimum bandwidth. This paper presents an implementation based on intelligent test and measurement system (ITMS), a data acquisition system architecture with multiprocessing capabilities that permits it to adapt the system’s sampling frequency throughout the experiment. The sampling rate can be controlled depending on the experiment’s specific requirements by using an external dc voltage signal or by defining user events through software. The system takes advantage of the high processing capabilities of the ITMS platform to implement a data reduction mechanism based in lossless data compression algorithms which are themselves based in periodic deltas

    A versatile trigger and synchronization module with IEEE1588 capabilities and EPICS support.

    Get PDF
    Event timing and synchronization are two key aspects to improve in the implementation of distributed data acquisition (dDAQ) systems such as the ones used in fusion experiments. It is also of great importance the integration of dDAQ in control and measurement networks. This paper analyzes the applicability of the IEEE1588 and EPICS standards to solve these problems, and presents a hardware module implementation based in both of them that allow adding these functionalities to any DAQ. The IEEE1588 standard facilitates the integration of event timing and synchronization mechanisms in distributed data acquisition systems based on IEEE 803.3 (Ethernet). An optimal implementation of such system requires the use of network interface devices which include specific hardware resources devoted to the IEE1588 functionalities. Unfortunately, this is not the approach followed in most of the large number of applications available nowadays. Therefore, most solutions are based in software and use standard hardware network interfaces. This paper presents the development of a hardware module (GI2E) with IEEE1588 capabilities which includes USB, RS232, RS485 and CAN interfaces. This permits to integrate any DAQ element that uses these interfaces in dDAQ systems in an efficient and simple way. The module has been developed with Motorola's Coldfire MCF5234 processor and National Semiconductors's PHY DP83640T, providing it with the possibility to implement the PTP protocol of IEEE1588 by hardware, and therefore increasing its performance over other implementations based in software. To facilitate the integration of the dDAQ system in control and measurement networks the module includes a basic Input/Output Controller (IOC) functionality of the Experimental Physics and Industrial Control System (EPICS) architecture. The paper discusses the implementation details of this module and presents its applications in advanced dDAQ applications in the fusion community

    On the efficiency and sensitivity of a pyramidal classification algorithm

    Get PDF
    In this paper we propose a Pyramidal Classification Algorithm, which together with an appropriate aggregation index produces an indexed pseudo-hierarchy (in the strict sense) without inversions nor crossings. The computer implementation of the algorithm makes it possible to carry out some simulation tests by Monte Carlo methods in order to study the efficiency and sensitivity of the pyramidal methods of the Maximum, Minimum and UPGMA. The results shown in this paper may help to choose between the three classification methods proposed, in order to obtain the classification that best fits the original structure of the population, provided we have an a priori information concerning this structure.Pyramidal classification methods, aggregation index, pseudo-hierarchy, Robinsonian dissimilarity, Monte Carlo evaluation, overlapping clusters

    Wireless monitoring for cliff stabilization at La Clua (Pre-Pyrenees, Spain)

    Get PDF
    La Clua is a village at the foot of a conglomerate cliff (Pre-Pyrenees, Spain), eventually af-fected by rockfalls. After last big event, in 2009, that affected a house of the village, a rope net was installed to protect the village. In order to obtain information about the performance of the protecting net, but also to gain knowledge on the triggering mechanism a wireless mon-itoring system was installed. The system is equipped with sensors (4 crackmeters, 2 biaxial tiltmeters, 2 rope tension load cells and 2 thermistors) that are measuring the changes on two unstable boulders (one protected with the net, the other not). Sensors are connected to wire-less dataloggers, installed next to the sensors and send data to the gateway. In this site, gate-way is located 250 m far from the furthest logger, but thanks to the long range technology of the system, loggers can be up to several km far from the gateway and the data which is pushed to an internet server every 15 minutes. Preliminary results show that no relevant movements have been observed in the boulders, since February 2016. Only some slight changes of around 0.15º have been observed after heavy rainfall events in spring.Postprint (published version

    Fast determination of a novel iron chelate prototype used as a fertilizer by liquid chromatography coupled to a diode array detector

    Full text link
    The environmental risk of the application of synthetic chelates has favored the implementation of new biodegradable ligands to correct Fe-deficient plants. This study developed and validated an analytical method for determination of a new prototype iron chelate-Fe(III)-benzeneacetate, 2-hydroxy-α-[(2-hydroxyethyl)amino]-(BHH/Fe3+) based on liquid chromatography with diode array detection, as a potential sustainable alternative. Chromatographic analysis was performed on a LiChrospher RP-18 in reverse-phase mode, with a mobile phase consisting of a mixture of acetonitrile (solvent A) and sodium borate buffer 0.20 mM at pH = 8 (solvent B) at a flow rate of 1.0 mL/min in isocratic elution mode. This method was fully validated and found to be linear from the limit of quantification (LOQ) to 50 mg/L and precise (standard deviation below 5%). The proposed method was demonstrated to be selective, precise, and robust. The developed methodology indicated that it is suitable for the quantification of iron chelate BHH/Fe3+The authors gratefully acknowledge the financial support by the Spanish Ministry of Economy and Competitiveness Project RTI2018-096268-B-I00, and the Comunidad de Madrid (Spain) and Structural Funds 2014−2020 (ERDF and ESF) project AGRISOST-CM S2018/BAA-433

    Environmental transcriptome analysis reveals physiological differences between biofilm and planktonic modes of life of the iron oxidizing bacteria Leptospirillum spp. in their natural microbial community

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Extreme acidic environments are characterized by their high metal content and lack of nutrients (oligotrophy). Macroscopic biofilms and filaments usually grow on the water-air interface or under the stream attached to solid substrates (streamers). In the Río Tinto (Spain), brown filaments develop under the water stream where the Gram-negative iron-oxidizing bacteria <it>Leptospirillum </it>spp. (<it>L. ferrooxidans </it>and <it>L. ferriphilum</it>) and <it>Acidithiobacillus ferrooxidans </it>are abundant. These microorganisms play a critical role in bioleaching processes for industrial (biominery) and environmental applications (acid mine drainage, bioremediation). The aim of this study was to investigate the physiological differences between the free living (planktonic) and the sessile (biofilm associated) lifestyles of <it>Leptospirillum </it>spp. as part of its natural extremely acidophilic community.</p> <p>Results</p> <p>Total RNA extracted from environmental samples was used to determine the composition of the metabolically active members of the microbial community and then to compare the biofilm and planktonic environmental transcriptomes by hybridizing to a genomic microarray of <it>L. ferrooxidans</it>. Genes up-regulated in the filamentous biofilm are involved in cellular functions related to biofilm formation and maintenance, such as: motility and quorum sensing (<it>mqsR, cheAY, fliA, motAB</it>), synthesis of cell wall structures (<it>lnt, murA, murB</it>), specific proteases (<it>clpX/clpP</it>), stress response chaperons (<it>clpB, clpC, grpE-dnaKJ, groESL</it>), etc. Additionally, genes involved in mixed acid fermentation (<it>poxB</it>, <it>ackA</it>) were up-regulated in the biofilm. This result, together with the presence of small organic acids like acetate and formate (1.36 mM and 0.06 mM respectively) in the acidic (pH 1.8) water stream, suggests that either <it>L. ferrooxidans </it>or other member of the microbial community are producing acetate in the acidophilic biofilm under microaerophilic conditions.</p> <p>Conclusions</p> <p>Our results indicate that the acidophilic filaments are dynamic structures in which different mechanisms for biofilm formation/dispersion are operating. Specific transcriptomic fingerprints can be inferred for both planktonic and sessile cells, having the former a more active TCA cycle, while the mixed acid fermentation process dominate in the latter. The excretion of acetate may play a relevant ecological role as a source of electron donor for heterotrophic Fe<sup>3+ </sup>reducers like some Alphaproteobacteria, <it>Acidobacterium </it>spp. and <it>Sulfobacillus </it>spp., also present in the biofilm. Additionally, acetate may have a negative effect on bioleaching by inhibiting the growth of chemolithotrophic bacteria.</p

    Análisis de la uniformidad de riego en sistemas de aspersión semiportátil con aspersores de gran tamaño

    Get PDF
    La sostenibilidad en la agricultura de regadío depende en gran medida de conseguir una alta eficiencia de aplicación en el riego. Es muy importante conocer los factores que afectan a la uniformidad de riego, especialmente en aspersores semi-portátiles de gran tamaño, que son un sistema muy común en áreas áridas y semiáridas, como Irán. Hasta el momento, la uniformidad de distribución del agua aplicada no ha sido considerada cuantitativamente en la mayoría de las combinaciones de variables hidráulicas y meteorológicas con aspersores portátiles de gran tamaño. En este trabajo, se ha caracterizado el coeficiente de uniformidad (CU) analizando la influencia de los principales factores que le afectan, como la velocidad del viento (W), la presión de trabajo (P) y el marco de riego. Los ensayos de campo se realizaron con un solo aspersor al aire libre. Se aprecia un efecto significativo del viento, como parámetro meteorológico, sobre el CU bajo diferentes condiciones climáticas, en relación a la presión y la separación entre aspersores. Este comportamiento es muy similar al obtenido con aspersores de tamaño medio. Los criterios técnicos propuestos en los resultados se pueden utilizar para optimizar la gestión del riego por aspersión de acuerdo con factores de diseño adecuados para una amplia gama de condiciones climáticas y presión (es decir 450 y 500 kPa). Así, la relación entre la separación entre aspersores y el radio mojado no debe superar los 0,45 con el fin de alcanzar el coeficiente de diseño de uniformidad aceptable (80%) bajo condiciones de viento (>2 m s -1 ) en el sistema de riego

    Exploiting graphic processing units parallelism to improve intelligent data acquisition system performance in JET's correlation reflectometer

    Get PDF
    The performance of intelligent data acquisition systems relies heavily on their processing capabilities and local bus bandwidth, especially in applications with high sample rates or high number of channels. This is the case of the self adaptive sampling rate data acquisition system installed as a pilot experiment in KG8B correlation reflectometer at JET. The system, which is based on the ITMS platform, continuously adapts the sample rate during the acquisition depending on the signal bandwidth. In order to do so it must transfer acquired data to a memory buffer in the host processor and run heavy computational algorithms for each data block. The processing capabilities of the host CPU and the bandwidth of the PXI bus limit the maximum sample rate that can be achieved, therefore limiting the maximum bandwidth of the phenomena that can be studied. Graphic processing units (GPU) are becoming an alternative for speeding up compute intensive kernels of scientific, imaging and simulation applications. However, integrating this technology into data acquisition systems is not a straight forward step, not to mention exploiting their parallelism efficiently. This paper discusses the use of GPUs with new high speed data bus interfaces to improve the performance of the self adaptive sampling rate data acquisition system installed on JET. Integration issues are discussed and performance evaluations are presente
    corecore