1,009 research outputs found

    OGO-E space vehicle response to transient loading at Atlas booster engine cutoff

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    Computer program for OGO-E vehicle response analysis to transient loading during Atlas booster burnou

    Wide bandwidth LFM transmission through a wavelength-controlled photonic true time delay device

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    We demonstrate for the first time high quality wide bandwidth (600 MHz) LFM transmission through a wavelength-controlled photonic true time delay device with bandwidth-limited resolution and peak sidelobe level below -37 dB at 5 GHz

    Performance issues with photonic beamformers

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    A photonic beamformer is presented, having smooth behavior. Third-order nonlinearities, resulting from its optoelectronic components, are investigated, with emphasis on their impact on the contrast of imaging radars. This contrast is shown to be severely limited by the induced RF nonlinearities. Limitations on the allowable modulation index are studied for linearly-chirped pulses returned from clutter

    Plan estratégico para una alimentación sostenible, adecuada y sana en los escolares de Remedios, Cuba

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    The work consists of a plan proposed by the University of Remedios, Cuba, to improve the nutritional level of children and young people in the semi-internships of the municipality, to guarantee the variety and sustainability of agricultural products on the table, as well as their consumption. Thanks to this strong educational work, we contributed to improving the nutritional level of the students; For this, the 17 semi-internal centers of the territory and the four farms that guarantee these products in the educational centers were taken as a sample, they belong to the National Association of Small Farmers (ANAP). For the design of the strategic plan, investigative methods were applied, among are observation, survey, interview, and logical history that served to make the initial diagnosis and verify the final results. The work as a whole reveals a sustainable contribution of agricultural products on the table of schoolchildren, achieving a high nutritional level in children, adolescents, and young people of these educational centers with these characteristics of semi-internships from a stable and sustainable consumption of these products since 2020 to 2022 when the strategy was applied.El trabajo consiste en un plan propuesto por la universidad de Remedios, Cuba, para mejorar el nivel nutricional de los niños y jóvenes en los seminternos del municipio, para garantizar la variedad y sostenibilidad de los productos agrícolas en la mesa, así como su consumo. Gracias a este fuerte trabajo educativo se contribuyó a mejorar el nivel nutricional de los educandos; para ello se tomó como muestra a los 17 centros seminternos del territorio y las cuatro fincas que garantizan estos productos en los centros educacionales, las mismas pertenecen a la Asociación Nacional de Agricultores Pequeños (ANAP). Para el diseño del plan estratégico se aplicaron métodos investigativos entre los que se encuentran la observación, la encuesta, la entrevista y el histórico lógico que sirvieron para hacer el diagnóstico inicial y constatar los resultados finales. El trabajo en su conjunto revela una contribución sostenible de productos agrícolas en la mesa de los escolares lográndose un elevado nivel nutricional en los niños, adolescentes y jóvenes de estos centros educacionales con estas características de seminternos a partir de un consumo estable y sostenible de estos productos desde el 2020 hasta el 2022, cuando se aplicó la estrategia.&nbsp

    An active learning approach for statistical spoken language understanding

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    The final publication is available at Springer via http://dx.doi.org/10.1007/978-3-642-25085-9_67In general, large amount of segmented and labeled data is needed to estimate statistical language understanding systems. In recent years, different approaches have been proposed to reduce the segmentation and labeling effort by means of unsupervised o semi-supervised learning techniques. We propose an active learning approach to the estimation of statistical language understanding models that involves the transcription, labeling and segmentation of a small amount of data, along with the use of raw data. We use this approach to learn the understanding component of a Spoken Dialog System. Some experiments that show the appropriateness of our approach are also presented.Work partially supported by the Spanish MICINN under contract TIN2008-06856-C05-02, and by the Vicerrectorat d’Investigació, Desenvolupament i Innovació of the Universitat Politècnica de València under contract 20100982.García Granada, F.; Hurtado Oliver, LF.; Sanchís Arnal, E.; Segarra Soriano, E. (2011). An active learning approach for statistical spoken language understanding. En Progress in Pattern Recognition, Image Analysis, Computer Vision, and Applications. Springer Verlag (Germany). 7042:565-572. https://doi.org/10.1007/978-3-642-25085-9_67S5655727042De Mori, R., Bechet, F., Hakkani-Tur, D., McTear, M., Riccardi, G., Tur, G.: Spoken language understanding: A survey. IEEE Signal Processing Magazine 25(3), 50–58 (2008)Fraser, M., Gilbert, G.: Simulating speech systems. Computer Speech and Language 5, 81–99 (1991)Gotab, P., Bechet, F., Damnati, G.: Active learning for rule-based and corpus-based spoken labguage understanding moldes. In: IEEE Workshop Automatic Speech Recognition and Understanding (ASRU 2009), pp. 444–449 (2009)Gotab, P., Damnati, G., Becher, F., Delphin-Poulat, L.: Online slu model adaptation with a partial oracle. In: Proc. of InterSpeech 2010, Makuhari, Chiba, Japan, pp. 2862–2865 (2010)He, Y., Young, S.: Spoken language understanding using the hidden vector state model. Speech Communication 48, 262–275 (2006)Ortega, L., Galiano, I., Hurtado, L.F., Sanchis, E., Segarra, E.: A statistical segment-based approach for spoken language understanding. In: Proc. of InterSpeech 2010, Makuhari, Chiba, Japan, pp. 1836–1839 (2010)Riccardi, G., Hakkani-Tur, D.: Active learning: theory and applications to automatic speech recognition. IEEE Transactions on Speech and Audio Processing 13(4), 504–511 (2005)Segarra, E., Sanchis, E., Galiano, M., García, F., Hurtado, L.: Extracting Semantic Information Through Automatic Learning Techniques. International Journal of Pattern Recognition and Artificial Intelligence 16(3), 301–307 (2002)Tur, G., Hakkani-Tr, D., Schapire, R.E.: Combining active and semi-supervised learning for spoken language understanding. Speech Communication 45, 171–186 (2005

    Spectroscopy of 13B via the 13C(t,3He) reaction at 115 AMeV

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    Gamow-Teller and dipole transitions to final states in 13B were studied via the 13C(t,3He) reaction at Et = 115 AMeV. Besides the strong Gamow-Teller transition to the 13B ground state, a weaker Gamow-Teller transition to a state at 3.6 MeV was found. This state was assigned a spin-parity of 3/2- by comparison with shell-model calculations using the WBP and WBT interactions which were modified to allow for mixing between nhw and (n+2)hw configurations. This assignment agrees with a recent result from a lifetime measurement of excited states in 13B. The shell-model calculations also explained the relatively large spectroscopic strength measured for a low-lying 1/2+ state at 4.83 MeV in 13B. The cross sections for dipole transitions up to Ex(13B)= 20 MeV excited via the 13C(t,3He) reaction were also compared with the shell-model calculations. The theoretical cross sections exceeded the data by a factor of about 1.8, which might indicate that the dipole excitations are "quenched". Uncertainties in the reaction calculations complicate that interpretation.Comment: 11 pages, 6 figure

    Seasonal and interannual variability of dissolved oxygen around the Balearic Islands from hydrographic data

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    Oceanographic data obtained between 2001 and 2011 by the Spanish Institute of Oceanography (IEO, Spain) have been used to characterise the spatial distribution and the temporal variability of the dissolvedoxygen around the Balearic Islands (Mediterranean Sea). The study area includes most of the Western Mediterranean Sea, from the Alboran Sea to Cape Creus,atthe border between France and Spain. Dissolved Oxygen (DO) at thewatersurface is found to be in a state of equilibrium exchange with the atmosphere. In the spring and summer a subsurface oxygen supersaturation is observed due to the biological activity, above the subsurface fluorescence maximum. Minimum observed values of dissolved oxygen are related to theLevantine Intermediate Waters (LIW). An unusual minimum of dissolved oxygen concentrations were also recorded in the Alboran Sea Oxygen Minimum Zone. The Western Mediterranean Deep Waters (WMDW) and the Western Intermediate Waters (WIW) show higher values of dissolved oxygenthanthe Levantine Intermediate Waters due to their more recent formation. Using these dissolved oxygen concentrations it is possible to showthat the Western Intermediate Waters move southwards across the Ibiza Channel and the deep water circulates around the Balearic Islands. It has also been possible to characterise the seasonal evolution of the different watermassesandtheir dissolved oxygen content in a station in the Algerian sub-basin. Keywords: Ocean circulation, dissolved oxygen, water masses, Western Mediterranean Sea, Balearic SeaPost-print

    Performance issues with photonic beamformers

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    A photonic beamformer is presented, having smooth behavior. Third-order nonlinearities, resulting from its optoelectronic components, are investigated, with emphasis on their impact on the contrast of imaging radars. This contrast is shown to be severely limited by the induced RF nonlinearities. Limitations on the allowable modulation index are studied for linearly-chirped pulses returned from clutter

    Cellulose hydrolysis-hydrogenolysis to ethyleneglycol and propyleneglycol over Ru and heteropolyacid catalysts

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    Еthylene and propylene glycols (EG and PG) are widely used in industry to produce cooling systems and other valuable chemical products. But PG is non-toxic, therefore it is used in industries where EG can not be used: pharmaceutical, food, etc. This polyols produced by "one-pot" method, which is one of the promising and effective methods for producing alcohols from cellulose under harsh conditions. The purpose of this study was to determine the optimal composition of the solid bifunctional catalyst and the conditions of its preparation for the hydrolysis-hydrogenolysis of cellulose. Catalists are Ru-HPA/ZrO[2], RuHPA/Nb[2]O[5] and Ru/CsHPK. As a result of the study, the most promising catalyst system is 1%Ru/Cs[3.5]H[0.5]SiW[12]O[40]. In the presence of 1%Ru/CsHPA, the yield of 25% EG and 11% PG was detected (EG and PG selectivity is 60 and 27%). The activity of the catalysts was studied in the presence of Ca(OH)[2]

    Convective overshooting and production of s-nuclei in massive stars during their core He-burning phase

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    With the "post-processing" technique we explore the role of the convective overshooting on the production of s-nuclei in stellar models of different initial mass and metallicity (15MZAMS/M2515 \leq M_{ZAMS}/M_{\odot} \leq 25; 104Z0.0210^{-4} \leq Z \leq 0.02), considering a range of values for the parameter ff, which determines the overall efficiency of convective overshooting.We find enhancements in the production of s-nuclei until a factor 6\sim 6 (measured as the average overproduction factor of the 6 s-only nuclear species with 60A9060\lesssim A\lesssim90) in all our models of different initial mass and metallicity with ff in the range 0.010.0350.01{-}0.035 (i.e. models with overshooting) compared to the production obtained with "no-overshooting" models (i.e. models with the same initial mass and metallicity, but f=105f=10^{-5}). Moreover the results indicate that the link between the overshooting parameter ff and the s-process efficiency is essentially monotonic in all our models of different initial mass and metallicity. Also evident is the higher s-process efficiency when we progressively increase for a given f value both the mass of the models from 15 M_\odot to 25 M_\odot and the Z value from 104^{-4} to 0.02. We also briefly discuss the possible consequences of these results for some open questions linked to the s-process weak component efficiency, as well as a "rule of thumb" to evaluate the impact of the convective overshooting on the yields of a generation of stars.Comment: 12 pages, 6 figures, A&A accepted (corrected typos plus minor changes in order to fulfill the guidelines for A&A manuscripts
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