Weak convergence to a class of two-parameter Gaussian processes from a Lévy sheet

In this paper, we show an approximation in law, in the space of the continuous functions on $[0,1]^2$, of two-parameter Gaussian processes that can be represented as a Wiener type integral by processes constructed from processes that converge to the Brownian sheet. As an application, we obtain a sequence of processes constructed from a Lévy sheet that converges in law towards the fractional Brownian sheet

Weak convergence to a class of two-parameter Gaussian processes from a Lévy sheet

In this paper, we show an approximation in law, in the space of the continuous functions on $[0,1]^2$, of two-parameter Gaussian processes that can be represented as a Wiener type integral by processes constructed from processes that converge to the Brownian sheet. As an application, we obtain a sequence of processes constructed from a Lévy sheet that converges in law towards the fractional Brownian sheet

On the strong convergence of multiple ordinary integrals to multiple Stratonovich integrals

Given $\left\{W^{(m)}(t), t \in[0, T]\right\}_{m \geq 1}$, a sequence of approximations to a standard Brownian motion $W$ in $[0, T]$ such that $W^{(m)}(t)$ converges almost surely to $W(t)$, we show that, under regular conditions on the approximations, the multiple ordinary integrals with respect to $d W^{(m)}$ converge to the multiple Stratonovich integral. We are integrating functions of the type $$f\left(t_1, \ldots, t_n\right)=f_1\left(t_1\right) \cdots f_n\left(t_n\right) I_{\left\{t_1 \leq \cdots \leq t_n\right\}},$$ where for each $i \in\{1, \ldots, n\}, f_i$ has continuous derivatives in $[0, T]$. We apply this result to approximations obtained from uniform transport processes

Strong approximations of Brownian sheet by uniform transport processes.

Many years ago, Griego, Heath and Ruiz-Moncayo proved that it is possible to define realizations of a sequence of uniform transport processes that converges almost surely to the standard Brownian motion, uniformly on the unit time interval. In this paper we extend their results to the multi parameter case. We begin constructing a family of processes, starting from a set of independent standard Poisson processes, that has realizations that converge almost surely to the Brownian sheet, uniformly on the unit square. At the end the extension to the d-parameter Wiener processes is presented

Coinfection in a stochastic model for bacteriophage systems

A system modeling bacteriophage treatments with coinfections in a noisy context is analysed. We prove that in a small noise regime, the system converges in the long term to a bacteria-free equilibrium. Moreover, we compare the treatment with coinfection with the treatment without coinfection, showing how coinfection affects the convergence to the bacteria-free equilibrium

Arthritis in acute febrile neutrophilic dermatosis (Sweet's Syndrome)

Sir: Acute febrile neutrophilic dermatosis or Sweet's syndrome' is an uncommon condition characterised by fever, polymorphonuclear leucocytosis, painful erythematous cutaneous plaques, and a dense dermal infiltrate of neutrophils without vasculitis at the site of the skin lesions. Although many investigators suggest that acute febrile neutrophilic dermatosis is a hypersensitivity reaction,2 no defmitive cause is known. The role of the neutrophil as a cause or effect in this syndrome has not been clarified. Acute febrile neutrophilic dermatosis is histologically and clinically mimicked by several disorders, and the differential diagnosis with pyoderma gangrenosum3 and with some reactive erythemas such as erythema multiforme2 is usually difficult

LEARN-SQL: herramienta de gestión de ejercicios de SQL con autocorrección

Algunas herramientas de autocorrección existen ya en el ámbito de la docencia informática. No obstante en asignaturas de bases de datos el problema es especialmente complejo debido a la gran variedad de tipos de ejercicios (los sistemas existentes se limitan a consultas) y a que éstos no tienen solución única. Nuestro sistema tiene como objetivo corregir automáticamente cualquier tipo de sentencia SQL (consultas, actualizaciones, procedimientos, disparadores, creación de índices, etc.) y discernir si la respuesta aportada por el estudiante es o no correcta con independencia de la solución concreta que éste proponga. En esta comunicación presentaremos específicamente el módulo encargado de la gestión de ejercicios y todas las tipologías de estos que estamos utilizando en la actualidad.Peer Reviewe

Uso de LEARN-SQL en el aprendizaje cooperativo de bases de datos

En este artículo se describen los cambios efectuados en algunas asignaturas del área de bases de datos en dos vertientes: organizativa y tecnológica. En la primera, el objetivo principal ha sido la introducción de técnicas de aprendizaje cooperativo. En la segunda, el objetivo ha sido potenciar el autoaprendizaje y el autoevaluación a través de la herramienta LEARN-SQL. Los cambios relacionados con las dos vertientes se han aplicado, hasta el momento, a asignaturas distintas. Para finalizar el artículo, se hace una valoración de los resultados obtenidos, y se trazan las líneas de futuros cambios orientados a la combinación de las dos vertientes.Peer ReviewedPostprint (author’s final draft

E-assessment of relational database skills by means of LearnSQL

LearnSQL is a software system that allows the automatic and efficient e-learning and e-assessment of relational database skills. It has been used at the Barcelona School of Informatics for 18 semesters with an average of 200 students per semester. This paper shows the functionalities of LearnSQL subsystems by means of specific and understandable examples.Peer ReviewedPostprint (published version

Integració i avaluació de la competència genèrica transversal actitud adequada davant el treball en assignatures de bases de dades

El canvi al nou Espai Europeu d'Educació Superior va portar a la Facultat d’Informàtica de Barcelona de la Universitat Politècnica de Catalunya a incorporar competències genèriques tranversals en els seus plans d’estudi. En aquest article es presenta com s’ha integrat la competència actitud adequada davant el treball en les assignatures de bases de dades del Grau en Enginyeria Informàtica en la especialitat d’Enginyeria del Software, el mètode d’avaluació utilitzat i es comenten els resultats obtinguts en els darrers tres anys.Peer ReviewedPostprint (published version