11,471 research outputs found

    Big Data on Decision Making in Energetic Management of Copper Mining

    Get PDF
    Indexado en: Web of Science; Scopus.It is proposed an analysis of the related variables with the energetic consumption in the process of concentrate of copper; specifically ball mills and SAG. The methodology considers the analysis of great volumes of data, which allows to identify the variables of interest (tonnage, temperature and power) to reach to an improvement plan in the energetic efficiency. The correct processing of the great volumen of data, previous imputation to the null data, not informed and out of range, coming from the milling process of copper, a decision support systems integrated, it allows to obtain clear and on line information for the decision making. As results it is establish that exist correlation between the energetic consumption of the Ball and SAG Mills, regarding the East, West temperature and winding. Nevertheless, it is not observed correlation between the energetic consumption of the Ball Mills and the SAG Mills, regarding to the tonnages of feed of SAG Mill. In consequence, From the experimental design, a similarity of behavior between two groups of different mills was determined in lines process. In addition, it was determined that there is a difference in energy consumption between the mills of the same group. This approach modifies the method presented in [1].(a)http://www.univagora.ro/jour/index.php/ijccc/article/view/2784/106

    Intelligent Packaging Systems: Sensors and Nanosensors to Monitor Food Quality and Safety

    Get PDF
    Indexación: Web of Science y Scopus.The application of nanotechnology in different areas of food packaging is an emerging field that will grow rapidly in the coming years. Advances in food safety have yielded promising results leading to the development of intelligent packaging (IP). By these containers, it is possible to monitor and provide information of the condition of food, packaging, or the environment. This article describes the role of the different concepts of intelligent packaging. It is possible that this new technology could reach enhancing food safety, improving pathogen detection time, and controlling the quality of food and packaging throughout the supply chain.https://www.hindawi.com/journals/js/2016/4046061/cta

    Factors associated with postharvest ripening heterogeneity of "Hass" avocados (Persea americana Mill)

    Get PDF
    Indexación: Web of ScienceIntroduction. 'Hass' is the main avocado cultivar commercialized worldwide. The extended flowering period, very low percentage of fruit set and inability to ripen on the tree renders the fruit heterogeneous and unpredictable during postharvest management. The "triggered" and "ready-to-eat" growing markets for 'Hass' avocados are affected by the variable postharvest ripening or ripening heterogeneity which creates severe logistical problems for marketers and inconsistent quality delivery to consumers. Synthesis. The dry matter content, the current avocado harvest index that correlates very well with oil content, has been extensively used to harvest 'Hass' avocados to comply with the minimum standards to guarantee consumer satisfaction. However, previous work and empirical experience demonstrate that dry matter does not correlate on a fruit-to-fruit basis with time to reach edible ripeness. Thus, avocados of very different ages are harvested from individual trees, resulting in heterogeneous postharvest ripening of fruit within a specific batch. Several preharvest factors related to environmental and growing conditions and crop management as well as postharvest technology strategies influence the observed variability of postharvest ripening. Conclusion. Modern approaches based on studying the composition of individual fruits displaying contrasting postharvest ripening behavior, combined with non-destructive phenotyping techniques, seem to offer practical solutions for the fresh supply chain of avocados to sort fruit based on their ripening capacity.http://www.pubhort.org/fruits/2016/5/fruits160045.ht

    Self-similar transmission properties of aperiodic Cantor potentials in gapped graphene

    Full text link
    We investigate the transmission properties of quasiperiodic or aperiodic structures based on graphene arranged according to the Cantor sequence. In particular, we have found self-similar behaviour in the transmission spectra, and most importantly, we have calculated the scalability of the spectra. To do this, we implement and propose scaling rules for each one of the fundamental parameters: generation number, height of the barriers and length of the system. With this in mind we have been able to reproduce the reference transmission spectrum, applying the appropriate scaling rule, by means of the scaled transmission spectrum. These scaling rules are valid for both normal and oblique incidence, and as far as we can see the basic ingredients to obtain self-similar characteristics are: relativistic Dirac electrons, a self-similar structure and the non-conservation of the pseudo-spin. This constitutes a reduction of the number of conditions needed to observe self-similarity in graphene-based structures, see D\'iaz-Guerrero et al. [D. S. D\'iaz-Guerrero, L. M. Gaggero-Sager, I. Rodr\'iguez-Vargas, and G. G. Naumis, arXiv:1503.03412v1, 2015]

    Another derivation of the geometrical KPZ relations

    Full text link
    We give a physicist's derivation of the geometrical (in the spirit of Duplantier-Sheffield) KPZ relations, via heat kernel methods. It gives a covariant way to define neighborhoods of fractals in 2d quantum gravity, and shows that these relations are in the realm of conformal field theory

    Producción de huevos en Eurypodius latreillii Guérin, 1828 (Decapoda: Majidae) en el Estrecho de Magallanes, sur de Chile

    Get PDF
    Egg production and reproductive investment were studied in the spider crab Eurypodius latreillii from the Straits of Magellan, southern Chile. A total of 66 ovigerous females were analyzed, ranging in size from 29.0 to 62.9 mm carapace length. E. latreillii produced up to 15886 embryos, and clutch size increased with maternal size. Initial egg size was large (0.162 mm3), and the embryo volume increase during the incubation period was 32 %. Brood mortality was substantial (83 %), and since egg volume increase could not compensate for the egg loss, average egg mass volume decreased considerably during embryogenesis. The average brood mass at laying accounted for 13 % of the maternal body mass (on a wet mass basis), and this value coincides with previous findings concerning energy allocation for egg production in other brachyuran crabs. In general, our data regarding E. latreillii correspond well with those from spider crab species inhabiting the northern hemisphere. The large egg size of E. latreillii compared with majids from other geographical regions may be an indication of a latitudinal gradient in the reproductive biology of majid crabs. Future studies with spider crabs from the southern hemisphere are desirable to substantiate this assumption.Se estudió la producción de huevos y la inversión reproductiva del cangrejo araña Eurypodius latreillii proveniente del Estrecho de Magallanes, sur de Chile. Se analizaron un total de 66 hembras ovígeras con un rango de tamaños entre 29,0 y 62,9 mm de longitud de caparazón. E. latreilli produjo hasta un máximo de 15886 embriones, y el número de huevos aumentó con el tamaño de la hembra. El tamaño inicial del huevo fue grande (0,162 mm3) y el aumento del volumen embrionario durante el período de incubación fue de 32 %. La mortalidad de huevos fue considerable (83 %), y como el aumento en el volumen de los huevos no pudo compensar la pérdida de huevos, el promedio del volumen de la masa de los huevos disminuyó de forma considerable durante la embriogénesis. La masa de huevos representó un 13 % de la masa corporal de la madre, y este valor coincide con observaciones previas sobre la asignación de energía para la producción de huevos en otros braquiuros. En general, nuestros datos sobre E. latreillii concuerdan con datos sobre especies del cangrejo araña del hemisferio norte. El tamaño grande de huevos de E. latreillii comparado con Majidae de otras regiones geográficas podría ser interpretado como una indicación de un gradiente latitudinal en la biología reproductiva de cangrejos májidos. Para corroborar esta interpretación se requerirían estudios futuros con cangrejos araña del hemisferio sur

    SIGMA and XTE observations of the soft X-ray transient XTEJ1755-324

    Full text link
    We present observations of the X-ray transient XTEJ1755-324 performed during summer 1997 with the XTE satellite and with the SIGMA hard X-ray telescope onboard the GRANAT observatory. The source was first detected in soft X-rays with XTE on July 25 1997 with a rather soft X-ray spectrum and its outburst was monitored in soft X-rays up to November 1997. On September 16 it was first detected in hard X-rays by the French soft gamma ray telescope SIGMA during a Galactic Center observation. The flux was stronger on September 16 and 17 reaching a level of about 110 mCrab in the 40-80 keV energy band. On the same days the photon index of the spectrum was determined to be alpha =-2.3 +/- 0.9 (1 sigma error) while the 40-150 keV luminosity was about 8 x 10^{36} erg/s for a distance of 8.5 kpc. SIGMA and XTE results on this source indicate that this source had an ultrasoft-like state during its main outburst and a harder secondary outburst in September. These characteristics make the source similar to X-Nova Muscae 1991, a well known black hole candidate.Comment: 19 pages LaTeX, 6 Postscript figures included, Accepted by Astrophysical Journa
    corecore