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Medieval archaeology under the canopy with LiDAR. The (re)discovery of a medieval fortified settlement in Southern Italy
Get PDFDespite the recognized effectiveness of LiDAR in penetrating forest canopies, its capability for archaeological prospection can be strongly limited in areas covered by dense vegetation for the detection of subtle remains scattered over morphologically complex areas. In these cases, an important contribution to improve the identification of topographic variations of archaeological interest is provided by LiDAR-derived models (LDMs) based on relief visualization techniques. In this paper, diverse LDMs were applied to the medieval site of Torre Cisterna to the north of Melfi (Southern Italy), selected for this study because it is located on a hilly area with complex topography and thick vegetation cover. These conditions are common in several places of the Apennines in Southern Italy and prevented investigations during the 20th century. Diverse LDMs were used to obtain maximum information and to compare the performance of both subjective (through visual inspections) and objective (through their automatic classification) methods. To improve the discrimination/extraction capability of archaeological micro-relief, noise filtering was applied to Digital Terrain Model (DTM) before obtaining the LDMs. The automatic procedure allowed us to extract the most significant and typical features of a fortified settlement, such as the city walls and a tower castle. Other small, subtle features attributable to possible buried buildings of a habitation area have been identified by visual inspection of LDMs. Field surveys and in-situ inspections were carried out to verify the archaeological points of interest, microtopographical features, and landforms observed from the DTM-derived models, most of them automatically extracted. As a whole, the investigations allowed (i) the rediscovery of a fortified settlement from the 11th century and (ii) the detection of an unknown urban area abandoned in the Middle Ages
VI Jornada. 13 de marzo de 2018. De la Red Asturiana de Centros Sanitarios Libres de Tabaco. Respira en libertad
No full textPoster de la VI Jornada de la Red Asturiana de Centros Sanitarios Libres de TabacoVI Jornada de la Red Asturiana de Centros Sanitarios Libres de Tabaco. Respira en liberta
E.V.E. 2.0: Una revisión y adaptación de un método para el estudio cerámico
No full textIn any archaeological excavation the potteryfragments are the most frequent quantitativeremains, as a consequence it seems right to proposea methodology that can help in their study. Therefore,we intend to expose a method that will lead us toknow from a fragment of pottery the percentageof the pottery piece with respect to the total vesselwhich was part. This approach is not new sincebetween the eighties and nineties of the twentiethcentury, C. Orton, P. Tyers and A. Vince startedtalking about the estimated vessel equivalent (EVE).However, despite its advantages, it is a system littleused. On this basis we have designed a reviewed EVEadapted to the new technologies that allow us to gofurther and talk of EVE 2.0. Not only is a change inform, but also a deep methodological revision.En toda excavación arqueológica los fragmentos cerámicos son los restos cuantitativamente más frecuentes, por lo tanto parece acertado plantear una metodología que pueda ayudarnos en su estudio.Por ello, pretendemos exponer un método que nos permitirá conocer a través de un fragmento de cerámica el porcentaje de ese pedazo con respecto al total de la vasija de la cual formaba parte. Este planteamiento no es novedoso dado que entre los años ochenta y los noventa del siglo XX, C. Orton, P.Tyers y A. Vince comenzaron a hablar del equivalente de vasija estimado (EVE). Sin embargo, a pesar de sus ventajas, se trata de un sistema escasamente utilizado. Partiendo de esta base teórica hemos diseñado un EVE revisado y adaptado a las nuevas tecnologías, que nos permita ir más allá y poder hablar del EVE 2.0. No solo se trata de un cambi oen las formas, sino también una de revisión metodológica profunda
Bibliografía científica del SERIDA en RIA. Anexo 2017
No full textLas citas bibliográficas son la piedra angular de la propagación del conocimiento y el medio principal para evaluar la calidad de la investigación, así como para dirigir las inversiones en ciencia. Por tanto, y considerando que la ciencia se está haciendo cada vez más intensiva en datos, la práctica de citación de datos es fundamental para considerarlos como objeto de primera clase con la misma relevancia que los productos científicos que reflejan.
El anexo del año 2017 contiene la producción científica publicada en artículos de revistas incluidas en las bases de datos Thomson-ISI (SCI) por el personal investigador y colaborador del SERIDA durante el año 201
Optimized Design of a High Input-Voltage-Ripple-Rejection Converter for LED Lighting
No full textThe asymmetrical half-bridge (AHB) converter has been deeply analyzed as second stage in ac-dc light emitting diode (LED) drivers. Galvanic isolation, high reliability and high efficiency are their main advantages while a limited duty cycle range (i.e., 0-0.5) and a poor dynamic behavior are their main disadvantages. As second stage of an LED driver, the most demanding requirement for its control loop is cancelling the low-frequency ripple introduced by the first stage. According to its limited maximum attainable bandwidth, this is normally achieved by implementing a feedforward loop. Nonetheless, the static gain of the standard AHB converter presents a nonlinear relation between the output voltage and the duty cycle. As a consequence, the effectiveness of this feedforward loop is limited. In this paper, the use of the zeta AHB converter as second stage of an LED driver is analyzed and an optimized design is proposed. Regarding its advantages, it presents an extended duty cycle range (theoretically, 0-1.0). Besides, it presents a linear relation between the output voltage and the duty cycle. Therefore, although its dynamic behavior is still limited, it can perfectly cancel the low-frequency ripple introduced by the first stage of the LED driver by means of a straightforward feedforward loop. The optimized design proposed in this paper is focused on minimizing the losses in the magnetic components (transformer and inductor) by wisely choosing the value of the two turns ratios of the transformer
Desarrollo de nuevos recubrimientos para aceros avanzados de alta resistencia
No full textProyecto financiado dentro de la Convocatoria del Programa Asturias de ayudas a Centros Tecnológicos en el Principado de Asturias durante el periodo 2016-2017 de la Consejería de Empleo, Industria y Turismo. Nº de referencia IDI/2016/00028
Cooperative Control in a Hybrid DC/AC Microgrid based on Hybrid DC/AC Virtual Generators
No full textThis paper deals with the dynamic control of the DC bus voltage and the AC voltage magnitude and frequency in a hybrid DC/AC Microgrid (MG). In order to allow a high penetration of renewable energies, provide an increased system reliability during islanding and reduce the dependency on the mains, Energy Storage Systems (ESSs) are included in both the DC and AC grids. The MG is composed by a multiport solid-state-based transformation center, with connexion to the mains and a central battery energy storage system (BESS), and a flexible number of AC Nanogrids (NGs) coupled to a Low Voltage DC bus (LVDC) through DC/AC 3-phase Power Electronic Converters (PECs) operated as grid forming, hereinafter referred as Nanogrid Head Converters (NGHCs). The MG control presents two main characteristics: 1) A DC bus regulation scheme is proposed based on DC virtual generators and P/V DC droop that allows to adapt the participation in the power sharing for DC bus regulation and provides with an automatic transition between grid connected and islanding modes; 2) In order to provide a cooperative operation between the different AC NGs, allowing the automatic power sharing between them through the DC bus, a DC/AC virtual generator control scheme, based on the theory of Virtual Synchronous Machines (VSM), is proposed for its implementation in the NGHCs, thus coupling the control of the LVDC and the NGs. The theoretical discussion is supported with simulations.PCTI-FICYT
FEDER
Ministerio de economía y competitividad (España)2018 IEEE Energy Conversion Congress and Exposition (ECCE
Tuning the selectivities of Mg-Al mixed oxides for ethanol upgrading reactions through the presence of transition metals
No full textThe effect of the presence of reduced Co and Ni (chosen as representative metals because of their good activity
for dehydrogenation reactions) on the catalytic performance of basic mixed oxide (Mg-Al) for ethanol condensation
is studied in this work. This effect has been studied both in absence and in presence of hydrogen, and
considering the different steps of this complex reaction. Globally, best results were obtained with Co/MgAl,
under reducing atmosphere, at mild temperature (below 600 K). At these conditons, 1-butanol production rates
are up to eight times higher than the obtained with Mg-Al under inert atmosphere. Co has a marked activity in
the dehydrogenation step, that prevails over its less relevant activity in aldolization and hydrogenation reactions.
This result indicates the relevant role of this first reaction step. DRIFT spectroscopy analyses were carried
out to support the experimental results and to identify the role of hydrogen and metals on the oligomerization
and permanent adsorption processes, which can produce the deactivation of the catalyst.- Gobierno de España (CTQ2014-52956-C3-1-R)
- Gobierno del Principado de Asturias. Programa Severo Ochoa (PA-14-PF-BP14-105