1,722,025 research outputs found
A proposal for the demonstration of the ITER Remote Experimentation Centre with collaborating European Tokamaks
No full textThe ITER Remote Experimentation Centre is one of the projects currently under implementation within the International Fusion Energy Research Centre. The final objective of the REC is to allow researchers to take part in the experimentation on ITER from a remote location. This includes the possibility to receive in real-Time information about the status of the machine and experimental data and to interact with the machine control room. This paper first gives an overview on the current status of the REC project, and then it focuses on a proposal for the REC demonstration to be carried out in collaboration with European Tokamaks. Finally, a possible implementation plan for the demonstration is discussed. © 2015 IEEE
Experimental violations of Leggett-Garg inequalities on a quantum computer
No full textLeggett-Garg's inequalities predict sharp bounds for some classical correlation functions that address the quantum or classical nature of real-time evolutions. We experimentally observe the violations of these bounds on single- and multiqubit systems, in different settings, exploiting the IBM Quantum platform. In the multiqubit case, we introduce the Leggett-Garg-Bell's inequalities as an alternative to the previous ones. Measuring these correlation functions, we find quantum error mitigation to be essential to spot inequalities violations. Accessing only two qubit readouts, we assess Leggett-Garg-Bell's inequalities to emerge as the most efficient quantum coherence witnesses to be used for investigating quantum hardware, among those introduced. Our analysis highlights the limits of current quantum platforms, showing that the above-mentioned correlation functions deviate from theoretical prediction as the number of qubits and the depth of the circuit grow
A robust hierarchical clustering for georeferenced data
Full text linkThe detection of spatially contiguous clusters is a relevant task in geostatistics since near located observations might have similar features than distant ones. Spatially compact groups can also improve clustering results interpretation according to the different detected subregions. In this paper, we propose a robust metric approach to neutralize the effect of possible outliers, i.e. an exponential transformation of a dissimilarity measure between each pair of locations based on non-parametric kernel estimator of the direct and cross variograms (Fouedjio, 2016) and on a different bandwidth identification, suitable for agglomerative hierarchical clustering techniques applied to data indexed by geographical coordinates. Simulation results are very promising showing very good performances of our proposed metric with respect to the baseline ones. Finally, the new clustering approach is applied to two real-word data sets, both giving locations and top soil heavy metal concentrations
Modeling Local BES Indicators by Copula-Based Bayesian Networks
Full text linkIn Italy, the measure of the Equitable and Sustainable Well-being is provided by the Italian Institute of Statistics by means of a dashboard of basic and composite indicators. To investigate the dependence structure between the different domains of well-being, we propose the use of Non-Parametric Bayesian Networks based on the normal copula distribution, that allow to explore the conditional independence relationships between the composite indicators. The main advantage of the non-parametric models is that, as opposed to the parametric approach, they do not require any assumption on the marginal distributions of the variables. The proposed model is applied to the Equitable and Sustainable Well-being indicators measured at the provincial level and enriches the analysis of well-being by inspecting similarities and differences between Italian urban areas and territories
A rating system for post pulse data validation
No full textThe aim of an automatic data validation system in a fusion experiment is to account—after every shot—for any occurrence of faulty sensors and unreliable measurements, thus preventing the proliferation of poor pulse data. In the past years a prototype has been successfully developed at Frascati Tokamak Upgrade (FTU) on a small set of density measurements. The results have shown that the model can be further extended to plant and diagnostic data, and that the same system can be used to assign to raw data a quality factor, to be stored in the archive and to be used in the post-shot elaboration phase as a selection criterion. In this way, a data validation system can also provide data analysts with an useful tool to be used as a key—together with other significant parameters, like plasma current, or magnetic field—to search the archive for quality data. This paper will describe how, using soft computing techniques, both these functions have been implemented on FTU, providing the users with a simple interface for fault detection developed in an open source environment (PHP–MySQL), to be finalised into the realisation of an overall rating system for FTU data
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
Foggia medievale: spunti di ricerca sulla fisionomia urbana da sondaggi di scavo nel Dipartimento di Studi Umanistici
No full textIn occasione dei lavori di ristrutturazione del plesso del Dipartimento di Studi Umanistici dell’Università di Foggia, svolti nel 2010, sono stati effettuati due saggi di scavo archeologico, che hanno consentito di acquisire dati interessanti sull’uso nel periodo medievale e moderno di questo comparto cittadino ubicato ai limiti della città medievale, lambito su un lato dalla principale arteria stradale urbana (via Arpi); qui sorgeva, almeno a partire dalla metà del XIV secolo, il convento di S. Caterina, cui si affiancò nel tempo anche un ospedale, concesso nel 1597 all’ordine ospedaliero dei Fatebenefratelli, reggenti la struttura fino alla fine del XIX secolo.
Nel contributo si illustreranno sinteticamente i risultati dell’esplorazione condotta nel chiostro della chiesa di S. Caterina, identificato nel corso dei lavori di ristrutturazione, soffermandosi in particolare sul contributo fornito dai dati di scavo e dai relativi materiali alla lettura delle trasformazioni architettoniche e d’uso della porzione di fabbrica indagata. Attraverso poi la presentazione del piccolo scavo condotto all’interno di un ipogeo, scoperto sempre nel sottosuolo del Dipartimento, nell’angolo tra via Arpi e l’ipotetica linea di confine della città, rimarcata dall’attuale via Fuiani, si offriranno spunti di riflessione, pur all’interno di un quadro archeologicamente alquanto problematico, sulla fisionomia del sistema difensivo medievale della città e sulle sue successive trasformazioni
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