Search results for "design [electronics]"
showing 10 items of 505 documents
Active emulation of computer codes with Gaussian processes – Application to remote sensing
2020
Many fields of science and engineering rely on running simulations with complex and computationally expensive models to understand the involved processes in the system of interest. Nevertheless, the high cost involved hamper reliable and exhaustive simulations. Very often such codes incorporate heuristics that ironically make them less tractable and transparent. This paper introduces an active learning methodology for adaptively constructing surrogate models, i.e. emulators, of such costly computer codes in a multi-output setting. The proposed technique is sequential and adaptive, and is based on the optimization of a suitable acquisition function. It aims to achieve accurate approximations…
Algorithms for Computing Abelian Periods of Words
2012
Constantinescu and Ilie (Bulletin EATCS 89, 167--170, 2006) introduced the notion of an \emph{Abelian period} of a word. A word of length $n$ over an alphabet of size $\sigma$ can have $\Theta(n^{2})$ distinct Abelian periods. The Brute-Force algorithm computes all the Abelian periods of a word in time $O(n^2 \times \sigma)$ using $O(n \times \sigma)$ space. We present an off-line algorithm based on a $\sel$ function having the same worst-case theoretical complexity as the Brute-Force one, but outperforming it in practice. We then present on-line algorithms that also enable to compute all the Abelian periods of all the prefixes of $w$.
A note on easy and efficient computation of full abelian periods of a word
2016
Constantinescu and Ilie (Bulletin of the EATCS 89, 167-170, 2006) introduced the idea of an Abelian period with head and tail of a finite word. An Abelian period is called full if both the head and the tail are empty. We present a simple and easy-to-implement $O(n\log\log n)$-time algorithm for computing all the full Abelian periods of a word of length $n$ over a constant-size alphabet. Experiments show that our algorithm significantly outperforms the $O(n)$ algorithm proposed by Kociumaka et al. (Proc. of STACS, 245-256, 2013) for the same problem.
ECCOLA : a Method for Implementing Ethically Aligned AI Systems
2020
Various recent Artificial Intelligence (AI) system failures, some of which have made the global headlines, have highlighted issues in these systems. These failures have resulted in calls for more ethical AI systems that better take into account their effects on various stakeholders. However, implementing AI ethics into practice is still an on-going challenge. High-level guidelines for doing so exist, devised by governments and private organizations alike, but lack practicality for developers. To address this issue, in this paper, we present a method for implementing AI ethics. The method, ECCOLA, has been iteratively developed using a cyclical action design research approach. The method aim…
Continuous design control for machine learning in certified medical systems
2022
AbstractContinuous software engineering has become commonplace in numerous fields. However, in regulating intensive sectors, where additional concerns need to be taken into account, it is often considered difficult to apply continuous development approaches, such as devops. In this paper, we present an approach for using pull requests as design controls, and apply this approach to machine learning in certified medical systems leveraging model cards, a novel technique developed to add explainability to machine learning systems, as a regulatory audit trail. The approach is demonstrated with an industrial system that we have used previously to show how medical systems can be developed in a con…
Identificación de factores influyentes en el proceso de aprendizaje en estudios de máster
2019
[ES] La puesta en marcha de los postgrados ha supuesto, en muchos casos, la incorporación de metodologías más apropiadas a este nivel educativo. En el trabajo que se presenta se estudia la repercusión de una metodología, que combina el modelo tradicional y el design thinking, en el rendimiento académico de los estudiantes de un máster ofertado por la Universitat de València y enmarcado dentro de la rama de ciencias sociales y jurídicas. El estudio hace énfasis en si el resultado obtenido aplicando dicha metodología muestra diferencias atendiendo a factores del alumnado de tipo académico y personal (estudios universitarios previos, situación laboral, ...). Si dichas disparidades se confirmar…
Design Of Experiments for the optimization the process parameters of thixotropic aluminum alloy
2006
The success of the thixoforming process depends on the possibility to confer to material, when it is found in the semisolid state, a microstructure characterized by globular particles of solid phase surrounded by a continuous film of liquid phase; such microstructure is obtainable through particular thermo-mechanical treatments. In the present research, in order to optimize the influence of process parameters in the step in which the thixotropic properties are conferred to the AA7075 aluminum alloy, the statistic technique of the Design Of Experiments (DOE) has been used. The advantages in the application of such technique are expressible in terms of reduction the times of development of pr…
Designing theme-based tabletop exercise for identifying and dealing with coordination problems in emergencies
2016
Tabletop exercises (TTXs) are used to train managers and other actors to deal with emergencies. These exercises that focus on the organisational coordination are planned and controlled by exercise managers through scenarios with predetermined events that participants discuss and act upon. Such exercises may lead to actors being ill prepared to deal with dynamic and emergent situations and problems. To address this knowledge gap, we apply an action design research approach to develop a TTX structured around non-sequential themes instead of predetermined events, thus allowing the participants to identify their own problems during the exercise. Our research contributes to existing knowledge by…
Friction stir consolidation of aluminum machining chips
2017
Friction stir consolidation (FSC) is a solid-phase manufacturing process that consolidates metal powder, chips, or scraps into solid blocks via severe plastic deformation and solid state welding. It has the potential to be a more economical and âgreenâ process to recycle metal waste. In this study, solid discs were made from AA6061 aluminum alloy machining chips by FSC. The progression of the process was revealed by analyzing the motion of the tool, consolidating force, power history, and macro/microstructure of discs produced from a series of partial consolidation experiments. A bowl-shaped recrystallized zone in the vertical cross-sections of the disc products was observed and conside…
Thermo-mechanical analysis of irradiation swelling and design optimization of the IFMIF target assembly with bayonet backplate
2017
Abstract The availability of a high flux neutron source for testing candidate materials under irradiation conditions, which will be typically encountered in future fusion power reactors (ITER, DEMO, FPR), is a fundamental step towards the development of fusion energy. To this purpose, the International Fusion Materials Irradiation Facility (IFMIF) represents the reference option to provide the fusion community with a DEMO-relevant neutron source capable of irradiating samples at a damage rate of up to 20 dpa/fpy (in steel) in a volume of 0.5 l. In the framework of the engineering design activities of IFMIF, ENEA is committed in the design of the lithium target assembly (TA) with removable (…