1,721,012 research outputs found
Higher differentiability of solutions for a class of obstacle problems with variable exponents
No full textIn this paper we prove a higher differentiability result for the solutions to a class of obstacle problems in the form
\begin{equation*}
\label{obst-def0}
\min\left\{\int_\Omega F(x,Dw) dx : w\in \mathcal{K}_{\psi}(\Omega)\right\}
\end{equation*}
where is a fixed function called obstacle and \mathcal{K}_{\psi}(\Omega)=\{w \in W^{1,p(x)}_{0}(\Omega)+u_0: w \ge \psi \,\, \textnormal{a.e. in \Omega}\} is the class of the admissible functions, for a suitable boundary value . We deal with a convex integrand which satisfies the -growth conditions
\begin{equation*}\label{growth}|\xi|^{p(x)}\le F(x,\xi)\le C(1+|\xi|^{p(x)}),\quad p(x)>1
\end{equation*
Il ruolo delle vittime e delle organizzazioni non governative nella garanzia dei diritti umani
No full textPerovskite-Si solar cell: A three-terminal heterojunction bipolar transistor architecture
Full text linkOver the past decade, perovskite materials have attracted great interest for terrestrial photovoltaic (PV) applications thanks to their cheapness and excellent optoelectronic properties such as tunable bandgap, high absorption coefficient, long carrier lifetime and diffusion length. Perovskites have excellent potential for the development of high efficiency and low cost silicon-based tandem solar cells. Several research studies have been performed about perovskite/silicon tandem solar cells obtaining good conversion efficiencies of about 26%. In this work, we propose a perovksite-silicon solar cell based on the three-terminal hetero-junction bipolar transistor (3T-HBJT) architecture that overcomes several constraints of the series connected double junction cell - i.e. current matching and the need of tunnel junctions or recombination layers - exploiting a simpler structure and achieving high efficiency. In order to evaluate its performance potential, we adopt the classical Hovel model extended to deal with the 3T-HBT structure, demonstrating efficiencies up to 28.6% for cells without antireflection coating
HGA-based Auto-tuning of peltier coolers in PAIS project: New environmental monitoring and early wildfire detection system
No full textThis paper presents the PAIS system which is an innovative WSN (Wireless Sensor Network) for the environmental monitoring. The main goal of the PAIS system is to reduce the wildfire damages with early detection and suppression. Moreover, each PAIS node can integrate a number of heterogeneous sensors in order to operate a complete environmental monitoring. Usually the sensor nodes are located in wild areas and exposed to severe weather conditions, hence particular attention has been given to energy management, robustness and ruggedness to minimize maintenance costs and increase the dependability of the entire system. The fire detection is based on two infrared sensors whose accuracy is extremely affected by temperature. Hence, the sensor temperature is controlled by two Peltier coolers whose performances are automatically optimized with an innovative hybrid genetic algorithm. The proposed on-line hybrid optimization can be embedded as a fully-automated tool without any extrahardware the system. Experimental results prove the effectiveness of the proposed approach
HTA86 Health Technology Assessment in Hospitals: A Systematic Review on Methods and Practices
No full textBACKGROUND: Hospitals are at the forefront of health technology innovation. Being hospitals characterized by constrained budgets, competencies, and time, they need a reference framework to select value-for-money technologies. Contrary to what happens for Health Technology Assessment (HTA) at national/regional level, there are not generally accepted guidelines for running Hospital-Based Health Technology Assessment (HBHTA).
OBJECTIVES: This study aims at investigating how hospitals run HBHTA gathering evidence from what has been reported in the published literature so far about frameworks, criteria, methods, sources of evidence employed by hospitals to assess novel health technologies. The final purpose is developing a comprehensive and standardized synthesis of extant literature to advance both theory and practice of HBHTA.
METHODS: A systematic Cochrane-compliant literature review was carried out on three electronic databases (Scopus, PubMed, Web of Science) from 2007 to 2022. Primary and secondary articles focusing on the assessment by hospitals of novel health technologies were included. We employed a data extraction form that categorized and included the following information: country and aim of the study, hospital features (e.g., type and size), intervention investigated, health technology or procedure analysed, innovativeness of the technology, disease area, stakeholders involved, the employment (or not) of an existing HTA model/practice, criteria used to run HBHTA, methodologies and sources of evidence for each criteria, the phases followed in the evaluation and the presence (or not) of monitoring indicators.
RESULTS: Of the 703 papers extracted, 34 were included. In the selected studies, no standardised frameworks were employed, confirming that hospitals run HBHTA exercises without clear guidelines. We developed a novel framework for HBHTA by grouping the criteria used in the selected studies in multi-dimensional categories around the concepts of “value” and adoption “sustainability”.
CONCLUSIONS: There is no consensus on how to run HBHTA exercises. This research provides a novel framework for HBHTA
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
- …
