9,437 research outputs found

    Neural Network Modelling of Track Profile in Cold Spray Additive Manufacturing.

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    Cold spray additive manufacturing is an emerging technology that offers the ability to deposit oxygen-sensitive materials and to manufacture large components in the solid state. For further development of the technology, the geometric control of cold sprayed components is fundamental but not yet fully matured. This study presents a neural network predictive modelling of a single-track profile in cold spray additive manufacturing to address the problem. In contrast to previous studies focusing only on key geometric feature predictions, the neural network model was employed to demonstrate its capability of predicting complete track profiles at both normal and off-normal spray angles, resulting in a mean absolute error of 8.3%. We also compared the track profile modelling results against the previously proposed Gaussian model and showed that the neural network model provided comparable predictive accuracy, even outperforming in the predictions at cold spray profile edges. The results indicate that a neural network modelling approach is well suited to cold spray profile prediction and may be used to improve geometric control during additive manufacturing with an appropriate process planning algorithm.This research was funded by CSIRO’s Active Integrated Matter Future Science Platform (AIM FSP)under the testbed number: TB10_WB04

    Intervención psicoterapéutica cognitiva conductual grupal en pacientes ostomizados ambulatorios que presentan ansiedad y depresión asociadas a trastorno adaptativo

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    El presente estudio ha tenido como propósito esencial la aplicación y evaluación de un programa de corte cognitivo-conductual, para el manejo de los síntomas de ansiedad y depresión, en pacientes ostomizados. A través de un diseño de investigación de pretest, postest, con un solo grupo, fue evaluada la eficacia de una intervención cognitivo-conductual en grupo, aplicado a pacientes ostomizados que presentan trastorno de adaptación mixto. La muestra estuvo integrada por nueve pacientes con una edad promedio de 54 años, 4 eran mujeres y 5 eran hombres. El tratamiento fue ofrecido en 15 sesiones, una vez a la semana, con una duración de dos horas por sesión. Se utilizó para evaluar los síntomas de ansiedad y depresión en los participantes el inventario de ansiedad y depresión de Beck. Se pudo comprobar mediante el análisis estadístico de los resultados pretest y postest que la Terapia Cognitiva Grupal es efectiva en el tratamiento de pacientes ostomizados con trastorno adaptativo mixto debido a que el post test demostró que después de la aplicación del tratamiento se redujeron los síntomas depresivos y de ansiedad en el grupo de ostomizados

    The experience of preparing a closing session

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    This short article explains the development of a closing project developed with students of English as a foreign language. The project emerged with the idea of innovating in the classroom and trying to make links with their reality which could help developed a more meaningful process. Students involved study English for different reasons but most of them do it as a complementary activity for their job or study. They attend classes on the weekends so this project was enhanced also with the intention to break the old scheme of the foreign language as an additional but unconnected activity. The cooperative work and the motivation arisen from this task were some of the more valuable results

    Archaeological and geomagnetic surveys in Cerro de la Cabeza and Cerro del Mármol, Northern Sector of the copper age settlement of Valencina (Seville). Campaign in 2014

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    En el presente artículo presentamos los resultados de una primera campaña de prospección en la supuesta área poblacional del yacimiento de Valencina de la Concepción, que se encuentra 6 km al oeste de la actual ciudad de Sevilla. En concreto efectuamos una prospección geo-magnética, una recogida de material en superficie y perforaciones manuales de las anomalías registradas en dos parcelas vecinas, situadas en la parte septentrional de Valencina. En resumen, en la campaña de prospección en la “Parcela Municipal del Cerro de la Cabeza” y la parte meridional de la parcela del “Cerro Mármol” se ha detectado una multitud de anomalías circulares y elipsoidales, que probablemente definen fosas, silos y “fondos de cabaña”. Por otro lado se ha documentado una gran cantidad de anomalías lineales. Las perforaciones manuales realizadas nos permiten reconocer la mayoría de estas anomalías como fosos. De esta manera nos ha sido posible reconocer diversos fosos, quizás asociables a tres recintos, que han sido utilizados en distintos momentos y están situados en la parte septentrional de Valencina. La cerámica recogida durante la prospección de superficie nos permite datar la mayoría de los hechos documentados en el CalcolíticoThe present article offers the results of a first survey campaign in the supposed settlement area of the site of Valencina de la Concepción, which is situated 6 km west of the modern city of Seville. Especially on two neighbouring areas in the Northern part of Valencina we undertook geomagnetic and an archaeological surveys and manual drillings of the anomalies registered. To sum up, the geo-magnetic survey in the “Parcela Municipal del Cerro de la Cabeza” and the Southern part of the area “Cerro Mármol” delivered a great number of circular and oval anomalies, which probably represent pits, silos and houses with sunken floors. On the other hand, several linear anomalies were documented. The manual drillings allow us to define the majority of these structures as ditches. Maybe they are related with three ditched enclosures, which should have been operative in different moments. The ceramic material found during the archaeological survey speaks for a Chalcolithic dating of the majority of the documented structure

    Systematic mapping review of interventions to prevent blood loss, infection and relapse in orthognathic surgery

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    This systematic mapping review aims to identify, describe, and organize the currently available evidence in systematic reviews (SR) and primary studies regarding orthognathic surgery (OS) co-interventions and surgical modalities, focusing on the outcomes blood loss, infection and relapse. A comprehensive search strategy was performed to identify all SRs, randomized controlled trials and observational studies that evaluate surgical modalities and perioperative co-interventions in OS that evaluate the outcomes blood loss, infection and relapse, regardless of language or publication date. Searches were conducted in MEDLINE, EMBASE, Epistemonikos, Lilacs, Web of Science, and CENTRAL. In addition, grey literature was screened. 27 SRs and 150 primary studies fulfilled the inclusion criteria, 91 from SRs, and 59 from our search strategy. Overall, the quality of the SRs was graded as ?Critically low,? and only two SRs were rated as ?High? quality. 11 PICO questions were extracted from SRs and 31 from primary studies, which focused on osteosynthesis methods, surgical cutting devices, use of antibiotics, and induced hypotension. In addition, evidence bubble maps for each outcome were created to analyze in a visual manner the existing evidence. Future primary and secondary high-quality research should be addressed focused on the eight knowledge gaps identified in this mapping review. We concluded that the evidence mapping approach is a practical methodology for organizing the current evidence and identifying knowledge gaps in OS, helping to reduce research waste and canalize future efforts in developing studies for unsolved questions

    Multiplicity of Galactic Cepheids from long-baseline interferometry I. CHARA/MIRC detection of the companion of V1334 Cygni

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    We aim at determining the masses of Cepheids in binary systems, as well as their geometric distances and the flux contribution of the companions. The combination of interferometry with spectroscopy will offer a unique and independent estimate of the Cepheid masses. Using long-baseline interferometry at visible and infrared wavelengths, it is possible to spatially resolve binary systems containing a Cepheid down to milliarcsecond separations. Based on the resulting visual orbit and radial velocities, we can then derive the fundamental parameters of these systems, particularly the masses of the components and the geometric distance. We therefore performed interferometric observations of the first-overtone mode Cepheid V1334 Cyg with the CHARA/MIRC combiner. We report the first detection of a Cepheid companion using long-baseline interferometry. We detect the signature of a companion orbiting V1334 Cyg at two epochs. We measure a flux ratio between the companion and the Cepheid f = 3.10+/-0.08%, giving an apparent magnitude mH = 8.47+/-0.15mag. The combination of interferometric and spectroscopic data have enabled the unique determination of the orbital elements: P = 1938.6+/-1.2 days, Tp = 2 443 616.1+/-7.3, a = 8.54+/-0.51mas, i = 124.7+/-1.8{\deg}, e = 0.190+/-0.013, {\omega} = 228.7+/-1.6{\deg}, and {\Omega} = 206.3+/-9.4{\deg}. We derive a minimal distance d ~ 691 pc, a minimum mass for both stars of 3.6 Msol, with a spectral type earlier than B5.5V for the companion star. Our measured flux ratio suggests that radial velocity detection of the companion using spectroscopy is within reach, and would provide an orbital parallax and model-free masses.Comment: Published in A&

    Data-Efficient Neural Network for Track Profile Modelling in Cold Spray Additive Manufacturing

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    Cold spray is emerging as an additive manufacturing technique, particularly advantageous when high production rate and large build sizes are in demand. To further accelerate technology’s industrial maturity, the problem of geometric control must be improved, and a neural network model has emerged to predict additively manufactured geometry. However, limited data on the effect of deposition conditions on geometry growth is often problematic. Therefore, this study presents data-efficient neural network modelling of a single-track profile in cold spray additive manufacturing. Two modelling techniques harnessing prior knowledge or existing model were proposed, and both were found to be effective in achieving the data-efficient development of a neural network model. We also showed that the proposed data-efficient neural network model provided better predictive performance than the previously proposed Gaussian function model and purely data-driven neural network. The results indicate that a neural network model can outperform a widely used mathematical model with data-efficient modelling techniques and be better suited to improving geometric control in cold spray additive manufacturing
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