Search results for " Projection"
showing 10 items of 203 documents
Fixed point iterative schemes for variational inequality problems
2018
In a wide class of evolutionary processes, the problem of computing the solutions of an initial value problem is encountered. Here, we consider projected dynamical systems in the sense of \cite{Daniele} and references therein. Precisely, a projected dynamical system is an operator which solves the initial value problem: \begin{equation}\label{PDS}\frac{dx(t)}{dt}= \Pi_{\mathbb{K}}\left(x(t),-F(x(t))\right), \quad x(0)=x_0 \in \mathbb{K}, \, t \in [0,+\infty[,\tag{P}\end{equation} where $\mathbb{K}$ is a convex polyhedral set in $\mathbb{R}^n$, $F: \mathbb{K} \to \mathbb{R}^n$ and $\Pi_{\mathbb{K}}: \mathbb{R} \times \mathbb{K} \to \mathbb{R}^n$ is given as follows $\Pi_{\mathbb{K}}(x,-F(x))…
On the generalization of the Boltzmann equation
1974
Starting from the Liouville equation and making use of projection operator techniques we obtain a compact equation for the rate of change of then-particle momentum distribution function to any order in the density. This equation is exact in the thermodynamic limit. The terms up to second order in the density are studied and expressions are given for the errors committed when one makes the usual hypothesis to derive generalized Boltzmann equations. Finally the Choh-Uhlenbeck operator is obtained under additional assumptions.
Analysis of the XENON100 dark matter search data
2014
The XENON100 experiment, situated in the Laboratori Nazionali del Gran Sasso, aims at the direct detection of dark matter in the form of weakly interacting massive particles (WIMPs), based on their interactions with xenon nuclei in an ultra low background dual-phase time projection chamber. This paper describes the general methods developed for the analysis of the XENON100 data. These methods have been used in the 100.9 and 224.6 live days science runs from which results on spin-independent elastic, spin-dependent elastic and inelastic WIMP-nucleon cross-sections have already been reported.
Orthographic and Phonological Neighborhoods in Naming: Not All Neighbors Are Equally Influential in Orthographic Space
1997
Abstract The neighborhood size effect refers to the finding that single word naming is faster for stimuli that are orthographically similar to numerous lexical entries. We explored the nature of this phenomenon in five experiments with French pseudowords and words, and we examined the orthographic and the phonological characteristics of neighbors through quantitative analyses of a word corpus. Experiments 1 and 2 showed that the facilitatory effect of neighborhood size was determined by a subset of neighbors, called phonographic neighbors, which are also phonologically similar to the target letter string. Experiments 3 to 5 aimed at assessing the influence of phonographic neighbors as a fun…
Do Phonological Codes Constrain the Selection of Orthographic Codes in Written Picture Naming?
2001
Sound-to-print consistency of picture labels was manipulated in five experiments to investigate whether phonological codes constrain the selection of orthographic codes in written picture naming. In Experiments 1 and 2, participants wrote down picture names which were inconsistent or consistent in the phono-orthographic mapping defined either at the level of the word unit, i.e., heterographic homophones versus nonhomophones (Experiment 1), or at the sublexical level (Experiment 2). In neither experiment did phonographic consistency affect written latencies. Although more errors were observed for inconsistent than for consistent picture names, the observation of a similar error pattern in an…
Neighbourhood distribution interacts with orthographic priming in the lexical decision task
2004
Lexical decision tasks (LDTs) were used with a masked priming procedure to test whether neighbourhood distribution interacts with orthographic priming. Word targets had either ‘single’ neighbours when their two higher frequency orthographic neighbours were spread over letter positions (e.g., neighbours of LOBE: robe-loge) or ‘twin’ neighbours when they were concentrated on a single letter position (e.g., neighbours of FARD: lard-tard). All word targets were preceded by their highest frequency orthographic neighbour or by a control prime. An inhibitory priming effect was found for words with single neighbours, but not for words with twin neighbours, in both a yes/no LDT (Experiment 1a) and a…
Characterization of a medium size Xe/TMA TPC instrumented with microbulk Micromegas, using low-energy gamma-rays
2014
NEXT-MM is a general-purpose high pressure (10 bar, $\sim25$ l active volume) Xenon-based TPC, read out in charge mode with an 8 cm $\times$8 cm-segmented 700 cm$^2$ plane (1152 ch) of the latest microbulk-Micromegas technology. It has been recently commissioned at University of Zaragoza as part of the R&D of the NEXT $0\nu\beta\beta$ experiment, although the experiment's first stage is currently being built based on a SiPM/PMT-readout concept relying on electroluminescence. Around 2 million events were collected during the last months, stemming from the low energy $\gamma$-rays emitted by a $^{241}$Am source when interacting with the Xenon gas ($\epsilon$ = 26, 30, 59.5 keV). The localized…
Present Status and Future Perspectives of the NEXT Experiment
2014
Gómez Cadenas, Juan José et al.
NEXT-100 Technical Design Report (TDR). Executive summary
2012
[EN] In this Technical Design Report (TDR) we describe the NEXT-100 detector that will search for neutrinoless double beta decay (ßß0v) in 136XE at the Laboratorio Subterráneo de Canfranc (LSC), in Spain. The document formalizes the design presented in our Conceptual Design Report (CDR): an electroluminescence time projection chamber, with separate readout planes for calorimetry and tracking, located, respectively, behind cathode and anode. The detector is designed to hold a maximum of about 150 kg of xenon at 15 bar, or 100 kg at 10 bar. This option builds in the capability to increase the total isotope mass by 50% while keeping the operating pressure at a manageable level. The readout pla…
Initial results of NEXT-DEMO, a large-scale prototype of the NEXT-100 experiment
2013
NEXT-DEMO is a large-scale prototype of the NEXT-100 detector, an electroluminescent time projection chamber that will search for the neutrinoless double beta decay of Xe-136 using 100-150 kg of enriched xenon gas. NEXT-DEMO was built to prove the expected performance of NEXT-100, namely, energy resolution better than 1% FWHM at 2.5MeV and event topological reconstruction. In this paper we describe the prototype and its initial results. A resolution of 1.75% FWHM at 511 keV (which extrapolates to 0.8% FWHM at 2.5 MeV) was obtained at 10 bar pressure using a gamma-ray calibration source. Also, a basic study of the event topology along the longitudinal coordinate is presented, proving that it…