A cost-efficient DC active load laboratory solution

The increased use of DC renewable energy resources and DC storage systems, combined with the necessary reduction of energy waste, is boosting the development of DC smart grids. In this scenario, DC load emulation is of great importance. From the hardware point of view, DC buses stability of smart grids and the different DC/DC converter topologies must be tested. From the software point of view, smart grid strategies and job schedulers must be tested with different power absorption profiles. Moreover, DC load emulation can be useful for many other purposes, such as battery characterization, power supply testing, photovoltaic I-V curve measurements, etc. In this work, a cost-efficient DC Active Load (AL) solution is proposed. The principle of the circuit topology is a buck-boost-derived converter. This solution can be designed and tested considering the required voltage, current, and maximum input power. Both simulation and experimental results are shown on a 400 W size prototype. Thermal and electrical results validate the simulation model and the AL feasibility

High-rate quantum key distribution at short wavelength: performance analysis and evaluation of silicon single photon avalanche diodes

Abstract. Experimental results obtained with silicon single photon avalanche diodes (SPADs) in quantum key distribution (QKD) at short wavelengths reveal remarkable potential for application in local area networks (LAN) and for free-space transmission at high rate. Actual application prospects, however, depend on the performance level and on the suitability of practical systems using the available silicon SPAD devices. They can be essentially divided in two groups: planar p-n junction structures with a thin depletion layer (typically 1 mm); and reach-through structures with a thick depletion layer (from 20 mm to 150 mm). The physical mechanisms that control the device behaviour were investigated and the effect on the key parameters of the detector (quantum detection efficiency, dark counting rate, afterpulsing probability and photon-timing jitter) were thoroughly assessed. A quantitative analysis was made of the influence of such parameters on the quantum bit error rate (QBER). Actual parameters were measured and the attainable performance and system suitability of the two device types evaluated. Comparable performance is obtained, but from a system viewpoint thin SPADs appear inherently better suited to high-rate QKD applications, because of their faster response time, ruggedness, low voltage, low power dissipation and fabrication technology, which is simple, efficient, economical and compatible with monolithic integration of detector and associated circuits

Crack Propagation Analysis of Near-Surface Defects with Radial Basis Functions Mesh Morphing

Abstract Fracture mechanics analysis is nowadays adopted in several industrial fields to assess the capability of components to withstand fatigue loads. Finite Element Method (FEM) is a well-established tool for the evaluation of flaw Stress Intensity Factors (SIF) and for the survey of its propagation. Nevertheless the study of the growth of near-surface circular and elliptical cracks is still an arduous task to be faced with FEM. In fact, the interaction of the flaw with free surfaces leads the crack front to assume complex shapes, whose simulation cannot be easily accomplished. A possible answer to deal with such a problem is to use the mesh morphing technique, a nodal relocation methodology, that allows to cover different problems. In fact, with mesh morphing, it is possible to fit the baseline flaw front with the desired shape (generic shape) and to automatically simulate its evolution at a certain number of cycles. In the proposed work this approach is demonstrated exploiting ANSYS Mechanical as FEM tool and RBF Morph ACT Extension as mesh-morpher. The results of the proposed workflow are compared with those available in literature

PRODUÇÃO DE BIOMASSA DA CANA-DE-AÇÚCAR POR MEIO DO USO DE ORGANOMINERAIS EM CANA PLANTA E CANA SOCA

A área cultivada com cana-de-açúcar (Saccharum spp.) vem aumentando nos últimos anos, o que torna necessário realizar estudos para verticalizar a sua produção, em que o emprego de novas tecnologias pode proporcionar ganhos de produtividade nos canaviais. Nesse sentido, o presente trabalho objetivou avaliar o desenvolvimento da cana-de-açúcar, tanto em cana planta como em cana soca (cultivar SP81-3250), com o uso dos produtos organominerais, associados ou não, comparados com o uso da torta de filtro. O experimento foi desenvolvido em vaso (cerca de 50 kg de solo de textura arenosa), em Piracicaba/SP, durante oito meses, cerca de 120 dias por ciclo. O delineamento foi em blocos casualizados, com nove tratamentos e três repetições em cana planta, enquanto em cana soca foi utilizado esquema fatorial 2 x 5, com cinco tratamentos em dois níveis (com e sem aplicação de organomineral) e três repetições. De acordo com os resultados obtidos, pode-se averiguar que, não houve diferença significativa entre os tratamentos com organomineral e a torta de filtro no acúmulo de fitomassa na parte aérea e no sistema radicular em cana planta, ao passo que a aplicação de organomineral mostrou-se vantajosa para o aumento de matéria seca do sistema radicular em cana soca

Prevention of adolescent depression in the spanish-speaking world

ABSTRACT: This paper aims at presenting programs targeted at the prevention of adolescent depression applied with Spanish-speaking populations that have been developed in Spanish-speaking countries and are mostly published in Spanish. These programs have been developed under different cultural contexts in Spain and Latin-America. The main goal of this paper is to make the studies and movements of the Spanish-speaking literature in this field accessible to the non-Spanish-speaking part of the research community. Therefore, after an introduction referring to possible cultural differences regarding depression in general and epidemiological basics, several programs are introduced. In total 11 programs will be shortly presented and discussed. After revising the programs it can be concluded that in the Spanish-speaking world many programs have been developed and conducted following current state of the art-approaches for adolescent depression prevention. Further research is needed especially targeting possible cultural and contextual aspects of prevention measures and their efficacy and efficiency

Perfil epidemiológico de población atendida en el servicio de audiología de la fundación hospital universitario metropolitano 2012-2017

OBJETIVO: determinar el perfil epidemiológico de la población atendida en el servicio de Audiología prestado por la Fundación Hospital Universitario Metropolitano, como un primer esfuerzo de caracterización poblacional auditiva regional, que permita aportar a las estadísticas nacionales de prevalencia de las patologías auditivas. MÉTODOS: El presente trabajo responde a un estudio longitudinal retrospectivo de naturaleza cuantitativa que busca demostrar la prevalencia de la atención de los diferentes desordenes auditivos en la consulta de audiología del servicio de Audiología de la FHUM en un lapso comprendido entre los años 2012 y 2017. RESULTADOS: Los resultados arrojados se evidencian a partir de un análisis estadístico y de gráficas que fundamentan el comportamiento de las variables, definidas en la edad, el género, ocupación, procedencia y resultados de las evaluaciones audiológicas. Se generó una tabulación de frecuencias dividiendo el rango de la variable Edad en intervalos del mismo ancho, y contando el número de datos en cada intervalo. CONCLUSIONES: se puede establecer la necesidad que los especialistas soliciten la batería audiológica básica conformada por la audiometría, logoaudiometría e inmitancia acústica, en aras de establecer diagnósticos audiológicos completos, chequeo cruzado de pruebas, establecer la conducta a seguir, evidenciándose la necesidad de convenios que permitan el ordenamiento y autorización de las mismas

The Ship of Theseus Puzzle

Does the Ship of Theseus present a genuine puzzle about persistence due to conflicting intuitions based on “continuity of form” and “continuity of matter” pulling in opposite directions? Philosophers are divided. Some claim that it presents a genuine puzzle but disagree over whether there is a solution. Others claim that there is no puzzle at all since the case has an obvious solution. To assess these proposals, we conducted a cross-cultural study involving nearly 3,000 people across twenty-two countries, speaking eighteen different languages. Our results speak against the proposal that there is no puzzle at all and against the proposal that there is a puzzle but one that has no solution. Our results suggest that there are two criteria—“continuity of form” and “continuity of matter”— that constitute our concept of persistence and these two criteria receive different weightings in settling matters concerning persistence

The importance of a taste. A comparative study on wild food plant consumption in twenty-one local communities in Italy

A comparative food ethnobotanical study was carried out in twenty-one local communities in Italy, fourteen of which were located in Northern Italy, one in Central Italy, one in Sardinia, and four in Southern Italy. 549 informants were asked to name and describe food uses of wild botanicals they currently gather and consume. Data showed that gathering, processing and consuming wild food plants are still important activities in all the selected areas. A few botanicals were quoted and cited in multiple areas, demonstrating that there are ethnobotanical contact points among the various Italian regions (Asparagus acutifolius, Reichardia picroides, Cichorium intybus, Foeniculum vulgare, Sambucus nigra, Silene vulgaris, Taraxacum officinale, Urtica dioica, Sonchus and Valerianella spp.). One taxon (Borago officinalis) in particular was found to be among the most quoted taxa in both the Southern and the Northern Italian sites

Spectral study of the diffuse synchrotron source in the galaxy cluster Abell 523

The galaxy cluster Abell 523 (A523) hosts an extended diffuse synchrotron source historically classified as a radio halo. Its radio power at 1.4 GHz makes it one of the most significant outliers in the scaling relations between observables derived from multiwavelength observations of galaxy clusters: it has a morphology that is different and offset from the thermal gas, and it has polarized emission at 1.4 GHz typically difficult to observe for this class of sources. A magnetic field fluctuating on large spatial scales (similar to 1 Mpc) can explain these peculiarities but the formation mechanism for this source is not yet completely clear. To investigate its formation mechanism, we present new observations obtained with the LOw Frequency ARray at 120-168 MHz and the Jansky Very Large Array at 1-2 GHz, which allow us to study the spectral index distribution of this source. According to our data the source is observed to be more extended at 144 MHz than previously inferred at 1.4 GHz, with a total size of about 1.8 Mpc and a flux density S-144 MHz = (1.52 +/- 0.31) Jy. The spectral index distribution of the source is patchy with an average spectral index alpha similar to 1.2 between 144 MHz and 1.410 GHz, while an integrated spectral index alpha similar to 2.1 has been obtained between 1.410 and 1.782 GHz. A previously unseen patch of steep spectrum emission is clearly detected at 144 MHz in the south of the cluster. Overall, our findings suggest that we are observing an overlapping of different structures, powered by the turbulence associated with the primary and a possible secondary merger.Peer reviewe

De Pulchritudine non est Disputandum? A cross-cultural investigation of the alleged intersubjective validity of aesthetic judgment

Since at least Hume and Kant, philosophers working on the nature of aesthetic judgment have generally agreed that common sense does not treat aesthetic judgments in the same way as typical expressions of subjective preferences—rather, it endows them with intersubjective validity, the property of being right or wrong regardless of disagreement. Moreover, this apparent intersubjective validity has been taken to constitute one of the main explananda for philosophical accounts of aesthetic judgment. But is it really the case that most people spontaneously treat aesthetic judgments as having intersubjective validity? In this paper, we report the results of a cross-cultural study with over 2,000 respondents spanning 19 countries. Despite significant geographical variations, these results suggest that most people do not treat their own aesthetic judgments as having intersubjective validity. We conclude by discussing the implications of our findings for theories of aesthetic judgment and the purpose of aesthetics in general.info:eu-repo/semantics/acceptedVersio