Top-quark pair-production with one jet and parton showering at hadron colliders

We present heavy-flavor production in association with one jet in hadronic collisions matched to parton shower Monte Carlo predictions at next-to-leading order QCD with account of top-quark decays and spin correlations. We use the POWHEGBOX for the interface to the parton shower programs PYTHIA or HERWIG. Phenomenological studies for the LHC and the Tevatron are presented with particular emphasis on the inclusion of spin-correlation effects in top decay and the impact of the parton shower on the top-quark charge asymmetries. As a novel application of the present calculation the measurement of the top-quark mass is discussed.Comment: 4 pages latex, 6 figures, Procs. of XX International Workshop on Deep-Inelastic Scattering and Related Subjects (DIS 2012

Non-local spatially varying finite mixture models for image segmentation

[EN] In this work, we propose a new Bayesian model for unsupervised image segmentation based on a combination of the spatially varying finite mixture models (SVFMMs) and the non-local means (NLM) framework. The probabilistic NLM weighting function is successfully integrated into a varying Gauss¿Markov random field, yielding a prior density that adaptively imposes a local regularization to simultaneously preserve edges and enforce smooth constraints in homogeneous regions of the image. Two versions of our model are proposed: a pixel-based model and a patch-based model, depending on the design of the probabilistic NLM weighting function. Contrary to previous methods proposed in the literature, our approximation does not introduce new parameters to be estimated into the model, because the NLM weighting function is completely known once the neighborhood of a pixel is fixed. The proposed model can be estimated in closed-form solution via a maximum a posteriori (MAP) estimation in an expectation¿maximization scheme. We have compared our model with previously proposed SVFMMs using two public datasets: the Berkeley Segmentation dataset and the BRATS 2013 dataset. The proposed model performs favorably to previous approaches in the literature, achieving better results in terms of Rand Index and Dice metrics in our experiments.This study is partially supported by Secretaria de Estado de Investigacion, Desarrollo e Innovacion (DPI2016-80054-R, TIN2013-43457-R) and Agencia Valenciana de la Innovacion (INNVAL10/18/048). E.F.G was supported by the European Union's Horizon 2020 research and innovation programme under the Marie Skodowska-Curie grant agreement (No. 844646) and also acknowledges the support of NVIDIA GPU Grant Program.Juan -Albarracín, J.; Fuster García, E.; Juan, A.; Garcia-Gomez, JM. (2021). Non-local spatially varying finite mixture models for image segmentation. Statistics and Computing. 31(1):1-10. https://doi.org/10.1007/s11222-020-09988-w11031

Floating millenial chronologies of Pinus in the Sierra de Gredos (Spain)

This research has been carried out by some members of the “History and Dynamics of the Vegetal Landscape” Research Group of the Technical University of Madrid (Spain). The team has been working on the flora, vegetation and dendrochronology of the Sierra de Gredos (Ávila, Spain) for the last 20 years. Recently, we have implemented a new research field focused on the study of megafossils. All this data set has allowed us to develop an interpretation of the dynamics of mountain pine forests in this region

Thermal cycle for obtaining a Ni-Zn ferrite: (II) Influence of the cooling stage

Las piezas cerámicas obtenidas a partir de polvos de ferritas de composición (Cu0.12Ni0.23Zn0.65)Fe2O4 destacan como absorbentes de radiación electromagnética entre las ferritas de Ni-Zn dopadas con Cu, impidiendo interferencias entre dispositivos electrónicos. En un trabajo previo se estableció la metodología para diseñar la etapa de sinterización de un ciclo térmico que permite obtener las piezas cerámicas mencionadas con una microestructura adecuada (elevada densidad relativa y escaso crecimiento de grano) para que presenten unas buenas propiedades electromagnéticas. En este trabajo se ha estudiado la etapa de enfriamiento del mismo ciclo térmico (etapa siguiente a la de sinterización), determinando la influencia que ejerce la velocidad de enfriamiento sobre la densidad relativa en cocido, el tamaño medio de grano y la distribución de tamaños de grano, variando el tiempo de sinterización del ciclo térmico empleadoCeramic bodies formed from (Cu0.12Ni0.23Zn0.65)Fe2O4 ferrite powders stand out as electromagnetic radiation absorbers among Cu-doped Ni-Zn ferrites, preventing interference between electronic devices. In a preliminary study, a methodology was established for designing the sintering stage of a thermal cycle, which allows the foregoing ceramic bodies to be obtained with the appropriate microstructure (high relative density and little grain growth) to provide them with good electromagnetic properties. The present study examines the cooling stage (i.e. the stage following the sintering stage) of that thermal cycle and the influence of the cooling rate on fired relative density, average grain size, and grain size distribution, varying the sintering time of the thermal cycle use

Thermal cycle for obtaining a Ni-Zn ferrite: (I) Design of the sintering stage

Las piezas cerámicas obtenidas a partir de polvos de ferritas de composición (Cu0.12Ni0.23Zn0.65)Fe2O4 destacan como absorbentes de radiación electromagnética entre las ferritas de Ni-Zn dopadas con Cu, impidiendo interferencias entre dispositivos electrónicos. En este trabajo se ha establecido una metodología para diseñar la etapa de sinterización de un ciclo térmico, que permite obtener las piezas cerámicas mencionadas con una microestructura adecuada (elevada densidad relativa y escaso crecimiento de grano) para que presenten unas buenas propiedades electromagnéticas. La metodología establecida consiste, en primer lugar, en determinar las ecuaciones diferenciales que relacionan las velocidades de densificación y de crecimiento de grano con el tamaño medio de grano, la densidad relativa y la temperatura de sinterización, proponiendo en cada caso el mecanismo de difusión controlante de cada una de dichas velocidades. En segundo lugar, la integración simultánea de las dos ecuaciones de velocidad permite obtener la evolución de la densidad relativa y del tamaño medio de grano con el tiempo de sinterización a una temperatura previamente fijada. En tercer lugar, se ha determinado cómo dicha temperatura debe ir disminuyendo con el tiempo de sinterización para que, en cada instante, se mantenga una velocidad de densificación relativamente alta evitando al mismo tiempo que la velocidad de crecimiento de grano provoque un crecimiento irregular y exagerado de los mismosCeramic bodies formed from (Cu0.12Ni0.23Zn0.65)Fe2O4 ferrite powders stand out as electromagnetic radiation absorbers among Cu-doped Ni-Zn ferrites, preventing interference between electronic devices. This study establishes a methodology for designing the sintering stage of a thermal cycle, which allows the foregoing ceramic bodies to be obtained with the appropriate microstructure (high relative density and little grain growth) to provide them with good electromagnetic properties. The methodology consists, first, of determining the differential equations that relate the densification and grain-growth rates to average grain size, relative density, and sintering temperature, proposing the corresponding rate-controlling mass-transfer mechanism in each case. Secondly, the simultaneous integration of the two rate equations allows the evolution of relative density and average grain size with sintering time at a prefixed sintering temperature to be obtained. Thirdly, it is determined how this temperature needs to decrease with sintering time in order constantly to maintain a relatively high densification rate, while concurrently keeping the grain-growth rate from causing irregular and/or exaggerated grain growt

The influence of green microstructure and sintering parameters on precipitation process during copper-nickel-zinc ferrites sintering

Microstructural changes that occur during heat treatment of copper-nickel-zinc ferrites have been studied. The process of precipitation of the two types of crystals that occur during the sintering process has been analyzed. It is found that this process depends on dry relative density of the press specimens and on the following sintering parameters: sintering temperature, sintering time and cooling rate of the thermal cycle. Crystal precipitates characterization have been done by scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) analysis, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). These techniques have allowed to determine the nature of these crystals, which in this case correspond to zinc and copper oxides. It has been used two chemical reactions to explain the bulk precipitation and subsequent re-dissolution of these crystal precipitates during sintering.En este trabajo se han estudiado los cambios microestructurales que se producen durante el tratamiento térmico de las ferritas de cobre-níquel-cinc y se ha analizado el proceso de precipitación de los dos tipos de cristales que aparecen durante el proceso de sinterización. Se ha encontrado que este proceso depende de la densidad relativa en seco de las muestras compactadas y de las siguientes variables de la etapa de sinterización: temperatura y tiempo de sinterización y velocidad de enfriamiento. La caracterización de los cristales precipitados se ha realizado por microscopía electrónica de barrido (MEB), microanálisis por dispersión de energía de rayos X (EDX), difracción de rayos X (DRX), y espectroscopía de fotoelectrones de rayos X (XPS). Estas técnicas han permitido determinar la naturaleza de estos cristales, que en este caso corresponden a los óxidos de cinc y de cobre. Se han propuesto dos reacciones químicas que permiten explicar el proceso de precipitación y la posterior re-disolución de estos cristales precipitados durante la sinterización de las muestras

Numerical iterative methods for Markovian dependability and performability models: new results and a comparison

In this paper we deal with iterative numerical methods to solve linear systems arising in continuous-time Markov chain (CTMC) models. We develop an algorithm to dynamically tune the relaxation parameter of the successive over-relaxation method. We give a sufficient condition for the Gauss-Seidel method to converge when computing the steady-state probability vector of a finite irreducible CTMC, an a suffient condition for the Generalized Minimal Residual projection method not to converge to the trivial solution 0 when computing that vector. Finally, we compare several splitting-based iterative methods an a variant of the Generalized Minimal Residual projection method.Postprint (published version

A Novel Approach to Improve the Planning of Adaptive and Interactive Sessions for the treatment of Major Depression

[EN] Human Computer Interaction (HCI) is a research field which aims to improve the relationship between users and interactive computer systems. A main objective of this research area is to make the user experience more pleasant and efficient, minimizing the barrier between the users' cognition of what they want to accomplish and the computer's understanding of the user's tasks, by means of userfriendly, useful and usable designs. A bad HCI design is one of the main reasons behind user rejection of computer-based applications, which in turn produces loss of productivity and economy in industrial environments. In the eHealth domain, user rejection of computer-based systems is a major barrier to exploiting the maximum benefit from those applications developed to support the treatment of diseases, and in the worst cases a poor design in these systems may cause deterioration in the clinical condition of the patient. Thus, a high level of personalisation of the system according to users' needs is extremely important, making it easy to use and contributing to the system's efficacy, which in turn facilitates the empowerment of the target users. Ideally, the content offered through the interactive sessions in these applications should be continuously assessed and adapted to the changing condition of the patient. A good HCI design and development can improve the acceptance of these applications and contribute to promoting better adherence levels to the treatment, preventing the patient from further relapses. In this work, we present a mechanism to provide personalised and adaptive daily interactive sessions focused on the treatment of patients with Major Depression. These sessions are able to automatically adapt the content and length of the sessions to obtain personalised and varied sessions in order to encourage the continuous and long-term use of the system. The tailored adaptation of session content is supported by decision-making processes based on: (i) clinical requirements; (ii) the patient's historical data; and (iii) current responses from the patient. We have evaluated our system through two different methodologies: the first one performing a set of simulations producing different sessions from changing input conditions, in order to assess different levels of adaptability and variability of the session content offered by the system. The second evaluation process involved a set of patients who used the system for 14 to 28 days and answered a questionnaire to provide feedback about the perceived level of adaptability and variability produced by the system. The obtained results in both evaluations indicated good levels of adaptability and variability in the content of the sessions according to the input conditions.E. Fuster Garcia acknowledges the financial support from the "Torres Quevedo" program (Spanish Ministry of Economy and Competitiveness) co-funded by the European Social Fund (PTQ-12-05693), and the financial support from the Universitat Politecnica de Valencia under the Grant "Ayudas Para la Contratacion de Doctores para el Acceso al Sistema Espanol de Ciencia, Tecnologia e Innovacion" (PAID-10-14).Bresó Guardado, A.; Martínez Miranda, JC.; Fuster García, E.; García Gómez, JM. (2016). A Novel Approach to Improve the Planning of Adaptive and Interactive Sessions for the treatment of Major Depression. International Journal of Human-Computer Studies. 87:80-91. https://doi.org/10.1016/j.ijhcs.2015.11.003S80918