1,249 research outputs found
OGO-E space vehicle response to transient loading at Atlas booster engine cutoff
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
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
Survival, Nest Success and Productivity of Female Common Eiders (Somateria mollissima dresseri) on Flag Island, Harspwell, Casco Bay, Maine
In 2008, we concluded the 6th and final year of what was originally designed as a 5-year study to examine survival, recruitment and recovery rates of nesting common eiders (Somateria mollissima dresseri) on Flag Island, Harpswell, Maine. The total breeding population of common eiders on Flag Island was estimated to be about 500 nesting pairs in 2008, which is at the long term estimate of approximately 500-600 nesting pairs for this island. Both the 2007 and 2008 nesting estimates were, however, a marked improvement from the 2006 estimate when only 200 hens actually nested. This low point coincided with the beginning of significant non-nesting events by hen eiders in east Casco Bay at and leading up to two significant mortality events on the wintering grounds in Massachusetts. One cause contributing to these die-offs was determined to by an RNA virus. Nest success over the duration of this study was high at 75% in 2005, 74% in 2006 to 89% in 2007. Although the percentage of nesting great black-backed gulls increased during this investigation, the overall size of the nesting gull population remained fairly constant
Performance issues with photonic beamformers
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
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 agrÃcolas en la mesa, asà 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 agrÃcolas en la mesa de los escolares lográndose un elevado nivel nutricional en los niños, adolescentes y jóvenes de estos centros educacionales con estas caracterÃsticas de seminternos a partir de un consumo estable y sostenible de estos productos desde el 2020 hasta el 2022, cuando se aplicó la estrategia. 
High-Frequency Fatigue Behavior of Woven-Fiber-Fabric-Reinforced Polymer-Derived Ceramic-Matrix Composites
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66379/1/j.1151-2916.1998.tb02472.x.pd
An active learning approach for statistical spoken language understanding
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.GarcÃa Granada, F.; Hurtado Oliver, LF.; SanchÃs 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., GarcÃa, 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
Convective overshooting and production of s-nuclei in massive stars during their core He-burning phase
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 (; ), considering a range of values for the parameter , which
determines the overall efficiency of convective overshooting.We find
enhancements in the production of s-nuclei until a factor (measured as
the average overproduction factor of the 6 s-only nuclear species with
) in all our models of different initial mass and
metallicity with in the range (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 ).
Moreover the results indicate that the link between the overshooting parameter
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 to 25 M and the Z value from 10 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
Mode division multiplexing using an orbital angular momentum mode sorter and MIMO-DSP over a graded-index few-mode optical fibre
Mode division multiplexing (MDM)– using a multimode optical fiber’s N spatial modes as data channels to transmit N independent data streams – has received interest as it can potentially increase optical fiber data transmission capacity N-times with respect to single mode optical fibers. Two challenges of MDM are (1) designing mode (de)multiplexers with high mode selectivity (2) designing mode (de)multiplexers without cascaded beam splitting’s 1/N insertion loss. One spatial mode basis that has received interest is that of orbital angular momentum (OAM) modes. In this paper, using a device referred to as an OAM mode sorter, we show that OAM modes can be (de)multiplexed over a multimode optical fiber with higher than −15 dB mode selectivity and without cascaded beam splitting’s 1/N insertion loss. As a proof of concept, the OAM modes of the LP11 mode group (OAM−1,0 and OAM+1,0), each carrying 20-Gbit/s polarization division multiplexed and quadrature phase shift keyed data streams, are transmitted 5km over a graded-index, few-mode optical fibre. Channel crosstalk is mitigated using 4 × 4 multiple-input-multiple-output digital-signal-processing with <1.5 dB power penalties at a bit-error-rate of 2 × 10−3
Spectroscopy of 13B via the 13C(t,3He) reaction at 115 AMeV
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
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