Classification of factorial generalized down-up algebras

We determine when a generalized down-up algebra is a Noetherian unique factorisation domain or a Noetherian unique factorisation ring

Estrategias para el diseño de ayudas didácticas y pedagógicas que potencien el desarrollo de los procesos de lecto-escritura en niños y niñas de quinto de primaria

Es posible determinar en este ensayo los distintos componentes pedagógicos que optimicen el desarrollo de la intelectualidad del ser humano, como sujeto activo del aprendizaje que tiene verdaderamente un significado, donde el docente debe generar o proponer al estudiante las herramientas didácticas hábiles y útiles para incrementar desde su saber teórico-práctico la adquisición del conocimiento, explorando el entorno que lo rodea y desde allí presentar una propuesta que se funde o interprete en el progreso de las humanidades. Es por ello que la pedagogía tiene la finalidad de precisar los procesos adecuados de aprendizaje, potencializando ca vez más las habilidades en el educando en la lecto-escritura

A Deleting Derivations Algorithm for Quantum Nilpotent Algebras at Roots of Unity

This paper extends an algorithm and canonical embedding by Cauchon to a large class of quantum algebras. It applies to iterated Ore extensions over a field satisfying some suitable assumptions which cover those of Cauchon's original setting but also allows for roots of unity. The extended algorithm constructs a quantum affine space $A'$ from the original quantum algebra $A$ via a series of change of variables within the division ring of fractions $\mathrm{Frac}(A)$. The canonical embedding takes a completely prime ideal $P\lhd A$ to a completely prime ideal $Q\lhd A'$ such that when $A$ is a PI algebra, ${\rm PI}\text{-}{\rm deg}(A/P) = {\rm PI}\text{-}{\rm deg}(A'/Q)$. When the quantum parameter is a root of unity we can state an explicit formula for the PI degree of completely prime quotient algebras. This paper ends with a method to construct a maximum dimensional irreducible representation of $A/P$ given a suitable irreducible representation of $A'/Q$ when $A$ is PI.Comment: 27 page

Spectro-temporal heterogeneity measures from dense high spatial resolution satellite image time series: application to grassland species diversity estimation

Grasslands represent a significant source of biodiversity that is important to monitor over large extents. The Spectral Variation Hypothesis (SVH) assumes that the Spectral Heterogeneity(SH) measured from remote sensing data can be used as a proxy for species diversity. Here, we argue the hypothesis that the grassland’s species differ in their phenology and, hence, that the temporal variations can be used in addition to the spectral variations. The purpose of this study is to attempt verifying the SVH in grasslands using the temporal information provided by dense Satellite Image Time Series (SITS) with a high spatial resolution. Our method to assess the spectro-temporal heterogeneity is based on a clustering of grasslands using a robust technique for high dimensional data. We propose new SH measures derived from this clustering and computed at the grassland level. We compare them to the Mean Distance to Centroid (MDC). The method is experimented on 192 grasslands from southwest France using an intra-annual multispectral SPOT5 SITS comprising 18 images and using single images from this SITS. The combination of two of the proposed SH measures—the within-class variability and the entropy—in a multivariate linear model explained the variance of the grasslands’ Shannon index more than the MDC. However, there were no significant differences between the predicted values issued from the best models using multitemporal and monotemporal imagery. We conclude that multitemporal data at a spatial resolution of 10 m do not contribute to estimating the species diversity. The temporal variations may be more related to the effect of management practices

Rol de la seguridad privada frente al lavado de activos en Colombia

Rol de la seguridad privada frente al lavado de activos.The roll of the private security in front of launderin

Object-based classification of grasslands from high resolution satellite image time series using gaussian mean map kernels

This paper deals with the classification of grasslands using high resolution satellite image time series. Grasslands considered in this work are semi-natural elements in fragmented landscapes, i.e., they are heterogeneous and small elements. The first contribution of this study is to account for grassland heterogeneity while working at the object level by modeling its pixels distributions by a Gaussian distribution. To measure the similarity between two grasslands, a new kernel is proposed as a second contribution: the a-Gaussian mean kernel. It allows one to weight the influence of the covariance matrix when comparing two Gaussian distributions. This kernel is introduced in support vector machines for the supervised classification of grasslands from southwest France. A dense intra-annual multispectral time series of the Formosat-2 satellite is used for the classification of grasslands’ management practices, while an inter-annual NDVI time series of Formosat-2 is used for old and young grasslands’ discrimination. Results are compared to other existing pixel- and object-based approaches in terms of classification accuracy and processing time. The proposed method is shown to be a good compromise between processing speed and classification accuracy. It can adapt to the classification constraints, and it encompasses several similarity measures known in the literature. It is appropriate for the classification of small and heterogeneous objects such as grasslands

Desenvolvimento de um andarilho instrumentado para apoio a pacientes com mobilidade reduzida

As projeções feitas pelo Instituto Nacional de Estatística (INE) revelam um aumento crescente do envelhecimento da população Portuguesa. Uma das principais consequências do envelhecimento da população passa pelo aumento do nível de dependência dos idosos, havendo cada vez mais a necessidade de recorrer a dispositivos de compensação que lhes permitam uma vida mais ativa. Uma das principais limitações associada ao envelhecimento está relacionada com a locomoção, sendo o andarilho um dos dispositivos mais utilizados para apoio na marcha. Existem atualmente diversos modelos mecânicos de andarilho para utilização pela população idosa. No entanto, existe ainda pouca oferta ao nível de andarilhos instrumentados, que permitam uma monitorização e apoio na sua utilização. Este trabalho de projeto pretendeu desenvolver um conjunto de dispositivos de instrumentação que possam ser aplicados num andarilho, permitindo monitorizar a marcha e garantir uma aprendizagem mais eficaz associada com a sua utilização. Este trabalho descreve os dispositivos desenvolvidos para aplicação num andarilho e os testes funcionais que foram implementados. Este será um andarilho instrumentado, ou seja, equipado com a conjugação de diferentes sistemas que o fabricante não tem disponível