1,007 research outputs found

    Ret贸rica y comunicaci贸n en red: convergencias y analog铆as. Nuevas propuestas docentes

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    Education in Communication requires an on-going revision of methods. This paper suggests the introduction of theoretical and practical content of the Rhetoric science in the curricula of communication studies and other studies revolving around communication. This suggestion is based on the ANECA reports for the degree Bachelor of Arts in Communication, together with ANECA proposals for future journalists and communicators. Our fieldwork in the social network Facebook sheds positive results allowing us to interlink Rhetoric and our present communication environment. This present is mediated by social networks, emerging as a new paradigm. Retrieving parameters which devolve deep and critical thinking in favor of a more human communication should be of great use in our historical times.La docencia en Comunicaci贸n precisa una continua actualizaci贸n de sus f贸rmulas. Esta investigaci贸n propone la introducci贸n de contenidos te贸ricos y pr谩cticos de la ciencia Ret贸rica en los planes de estudio de aquellos campos que giran en torno a la comunicaci贸n, bas谩ndose en el informe sobre los T铆tulos de grado en Comunicaci贸n creado por la ANECA y en sus propuestas para los futuros periodistas y comunicadores. El trabajo de campo realizado sobre la red social Facebook arroja unos resultados que permiten entrelazar la Ret贸rica y nuestro presente comunicativo. Un presente mediado por la emergencia de las redes como nuevo paradigma. En un momento hist贸rico como el que vivimos ser谩 de gran utilidad recuperar unos par谩metros que devuelvan el pensamiento profundo y cr铆tico en favor de una comunicaci贸n m谩s humana

    Comparison of peristrophic multiplexing and a combination of angular and peristrophic holographic multiplexing in a thick PVA/acrylamide photopolymer for data storage

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    Two different types of multiplexing are used to store 90 holograms at the same location in a polyvinyl alcoholacrylamide photopolymer material. In the first, the 90 holograms are stored using only peristrophic multiplexing, whereas in the second a combination of angular and peristrophic multiplexing is used. The results (diffraction efficiency and dynamic range, M#) obtained with these two multiplexing techniques are compared. With the first, the dynamic range was M# = 13 and with the second M# = 8. An exposure schedule method is used to calculate the exposure time necessary to store the holograms with a more uniform, higher diffraction efficiency.This work was supported by the 鈥淢inisterio de Educaci贸n y Ciencia (Spain)鈥 under projects FIS2005-05881-C02-01 and FIS2005-05881-C02-02, and by the 鈥淕eneralitat Valenciana鈥 under Project GV06/172

    Holography: 50th anniversary of Dennis Gabor鈥檚 Nobel Prize: Part II. An engineering perspective

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    The holographic principle, discovered by Gabor, and realized by Leith & Upatnieks and Denisyuk is discussed. The intrinsic value of this idea and its continuing ability to motivate and inspire engineers and applied physicists is reviewed.Science Foundation Ireland, The Irish Research Council for Science Engineering and Technology, Enterprise Ireland, and the European Commission. 鈥淕eneralitat Valenciana鈥 of Spain (projects PROMETEO/2021/006 and IDIFEDER/2021/014, cofunded by European Union through the FEDER Programme) and by the 鈥淢inisterio de Ciencia e Innovaci贸n鈥 of Spain (projects FIS2017-82919-R and PID2019-106601RB-I00)

    Investigaci贸n de factores que afectan a las pensiones a nivel estatal y europeo

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    [ES] En este proyecto se va a realizar un an谩lisis de los factores que pueden afectar al valor de las pensiones en Espa帽a, tratando de realizar predicciones de las mismas. Se va a tener en cuenta la evoluci贸n temporal de las pensiones, y otros factores cr铆ticos extra铆dos de estudios previos. Se buscar谩n comparaciones con otros pa铆ses de la Uni贸n Europea, con modelos similares y/o dispares de financiaci贸n de las pensiones. Adem谩s se dotar谩 de perspectiva de g茅nero al an谩lisis comparando la evoluci贸n y previsi贸n del gasto en pensiones entre mujeres y hombres en Espa帽a. Se realizaran c谩lculos para saber el valor real que se deber铆a invertir en las pensiones.Pascual Gand铆a, I. (2018). Investigaci贸n de factores que afectan a las pensiones a nivel estatal y europeo. http://hdl.handle.net/10251/109332TFG

    Silver halide sensitized gelatin derived from BB-640 holographic emulsion

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    Silver halide sensitized gelatin (SHSG) is one of the most interesting techniques for the production of holographic optical elements, achieving relatively high sensitivity of photographic material with a low scattering of dichromated gelatin. Here we present experimental results for SHSG derived from the novel BB-640, a red-sensitive ultra-fine-grain emulsion from Holographic Recording Technologies (Steinau, Germany). The material is characterized before recording and after processing, and information about the thickness, absorption, and refractive-index modulation of the final holograms is obtained. The influence of the developer is analyzed, and diffraction efficiencies as great as 96.2% (after allowing for reflections) with a transmission of 1% and absorption and scatter losses of 2.8% are obtained with AAC developer. Our investigations reveal that high-quality SHSG transmission holograms may be obtained with the new BB-640 plates.This study was supported by the Comisi贸n Interministerial de Ciencia y Tecnolog铆a of Spain under project MAT97-0705-C02-02

    Imaging in white light with a thick-phase transmission holographic doublet

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    An afocal two-element holographic imaging system is presented. This system can be used to work in white light. The holographic optical elements (holographic lenses) are made as thick phase holograms on silver halide sensitized gelatin (SHSG) and they present a maximum diffraction efficiency of 75%. Geometrical conditions at reconstruction with coherent light and with white light are studied and a resolution test chart is imaged through the system, which shows a best resolution of 57 lines/mm for coherent illumination and 15 lines/mm for white light. The two-element holographic system presents a maximum diffraction efficiency of 56%

    Calculation of Nott dynamic retinoscopy

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    The accommodation that the eye uses to focus at a certain distance does not correspond exactly with the value of the accommodative stimulus. Such accommodation matches the diopter value of what is called the accommodative response. The Nott method is used in the optometric examination to measure the accommodative response at 40 cm by dynamic retinoscopy. The test is performed with the eye compensated by its neutralizing lens (PNL), obtained from binocular subjective examination. In the literature one can find a measurement procedure in which an accommodative test is situated at a distance of 40 cm, starting from that distance, the optometrist without moving the test, shifts the retinoscope until he finds the point of neutralization. The value of the lead or lag of accommodation is usually obtained by subtracting at 2.50D the inverse of the distance to the point of neutralization (in meters). The value of 2.50D is considered accommodative stimulus at 40 cm. The normal value of the accommodative response, considered for the test at 40 cm, is +0'50 or +0.25 D with a standard deviation of 卤 0'25D

    Experimental Conditions to Obtain Photopolymerization Induced Phase Separation Process in Liquid Crystal-Photopolymer Composite Materials under Laser Exposure

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    We analyze the experimental conditions necessary to obtain a photopolymerization induced phase separation process inside liquid crystal-photopolymer composite materials. Composites stored for 24 hours perform poorly in hologram recording but a good result is obtained if they are used recently prepared. We use a procedure combining heat and sonication to disarrange the liquid crystal structures formed during storage of the composite. We also propose incoherent light treatment after recording the hologram in order to evaluate if the phase separation evolved correctly during hologram recording.The work was supported by the 鈥淢inisterio de Econom铆a y Competitividad鈥 of Spain under Projects FIS2011-29803-C02-01 and FIS2011-29803-C02-02 and by the 鈥淕eneralitat Valenciana鈥 of Spain under Projects PROMETEO/2011/021 and ISIC/2012/013

    Influence of 4,4鈥-azobis (4-cyanopentanoic acid) in Transmission and Reflection Gratings Stored in a PVA/AA Photopolymer

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    Holographic transmission gratings with a spatial frequency of 2658 lines/mm and reflection gratings with a spatial frequency of 4553 lines/mm were stored in a polyvinyl alcohol (PVA)/acrylamide (AA) based photopolymer. This material can reach diffraction efficiencies close to 100% for spatial frequencies about 1000 lines/mm. However, for higher spatial frequencies, the diffraction efficiency decreases considerably as the spatial frequency increases. To enhance the material response at high spatial frequencies, a chain transfer agent, the 4,4鈥-azobis (4-cyanopentanoic acid), ACPA, is added to the composition of the material. Different concentrations of ACPA are incorporated into the main composition of the photopolymer to find the concentration value that provides the highest diffraction efficiency. Moreover, the refractive index modulation and the optical thickness of the transmission and reflection gratings were obtained, evaluated and compared to procure more information about the influence of the ACPA on them.This work was supported by the 鈥淕eneralitat Valenciana鈥 (Spain) under projects PROMETEOII/2015/015 and ISIC/2012/013 and by 鈥淢inisterio de Ciencia e Innovaci贸n鈥 (Spain) under projects FIS2014-56100-C2-1-P and FIS2015-66570-P

    Adulterant Detection in Peppermint Oil by Means of Holographic Photopolymers Based on Composite Materials with Liquid Crystal

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    Diffraction gratings are recorded in a holographic photopolymer containing nematic liquid crystal and peppermint oil. The presence of the oil modifies the polymerization and the holographic response. The composite containing oil adulterated with triethyl citrate obtains a diffraction efficiency related to the oil鈥檚 purity. The results obtained suggest the possibility of developing a holographic chemical analysis method for quality control of raw materials.Ministerio de Ciencia e Innovaci贸n (Spain) under projects; PID2019-106601RB-I00 FIS2017-82919-R; Generalitat Valenciana (Spain) under projects: IDIFEDER/2021/014; (cofunded by European Union through the FEDER Programme) PROMETEO 2021/006
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