1,999 research outputs found
Introduction
En este volumen 30 de la revista Arquitectonics hay una serie de artículos relacionados con el análisis de los lugares y espacios públicos de diferentes países, un tema de investigación muy importante en los últimos años, tal vez relacionado con la fuerte crisis financiera en todo el mundo vinculada a la vivienda.There is a set of articles related to the analysis of architectural and urban places from different countries, a very important research subject in the last years, perhaps related to the strong financial crisis around the world linked to housing.Peer Reviewe
On the search of a lost urban planning modernity: throughout the legacy of Lewis Mumford
Postprint (published version
Dos miradas teóricas de la evaluación formativa en el caso del aprendizaje por indagación: contraste entre la visión socio-constructivista y la visión socio-cultural
El aprendizaje de las ciencias y las matemáticas por indagación (ECMBI) es una tendencia en educación apoyada a nivel mundial por educadores, científicos, empresarios y políticos. Una gran cantidad de maestros en diversidad de culturas y medios sociales (Europa, América Latina, USA, Asia) están utilizando los principios de ECMBI en sus clases . Esta tendencia basa su propuesta de enseñanza-aprendizaje en supuestos que salen de una visión socio constructivista del aprendizaje. Dentro de este movimiento, diferentes investigadores han formulado propuestas y modelos de evaluación formativa que buscan apoyar el proceso de aprendizaje de los estudiantes. La presentación muestra que estas propuestas no dan cuenta de procesos sociales y culturales identificados por las visiones socio culturales del aprendizaje como constitutivos del proceso de enseñanza-aprendizaje. En primera instancia presentaré los modelos de evaluación formativa y los supuestos que las sustentan para enseguida introducir un modelo que tenga en cuenta las visiones socio-culturales del aprendizaje. La presentación está construida en el área de las ciencias pero con posibilidades de tejer vínculos con el área de las matemáticas
A fractal fragmentation model for rockfalls
The final publication is available at Springer via http://dx.doi.org/10.1007/s10346-016-0773-8The impact-induced rock mass fragmentation in a rockfall is analyzed by comparing the in situ block size distribution (IBSD) of the rock mass detached from the cliff face and the resultant rockfall block size distribution (RBSD) of the rockfall fragments on the slope. The analysis of several inventoried rockfall events suggests that the volumes of the rockfall fragments can be characterized by a power law distribution. We propose the application of a three-parameter rockfall fractal fragmentation model (RFFM) for the transformation of the IBSD into the RBSD. A discrete fracture network model is used to simulate the discontinuity pattern of the detached rock mass and to generate the IBSD. Each block of the IBSD of the detached rock mass is an initiator. A survival rate is included to express the proportion of the unbroken blocks after the impact on the ground surface. The model was calibrated using the volume distribution of a rockfall event in Vilanova de Banat in the Cadí Sierra, Eastern Pyrenees, Spain. The RBSD was obtained directly in the field, by measuring the rock block fragments deposited on the slope. The IBSD and the RBSD were fitted by exponential and power law functions, respectively. The results show that the proposed fractal model can successfully generate the RBSD from the IBSD and indicate the model parameter values for the case study.Peer ReviewedPostprint (author's final draft
El Mirascope
El Mirascope és un giny que ens pot ajudar a introduir el tema de l'òptica geomètrica. Produeix una imatge real, tan real que ens indueix a creure que l'objecte és vertaderament allà. Només quan intentem agafar aquest objecte fantasmal ens adonem que és una pura il•lusió òptica
Invariant Models for Causal Transfer Learning
Methods of transfer learning try to combine knowledge from several related
tasks (or domains) to improve performance on a test task. Inspired by causal
methodology, we relax the usual covariate shift assumption and assume that it
holds true for a subset of predictor variables: the conditional distribution of
the target variable given this subset of predictors is invariant over all
tasks. We show how this assumption can be motivated from ideas in the field of
causality. We focus on the problem of Domain Generalization, in which no
examples from the test task are observed. We prove that in an adversarial
setting using this subset for prediction is optimal in Domain Generalization;
we further provide examples, in which the tasks are sufficiently diverse and
the estimator therefore outperforms pooling the data, even on average. If
examples from the test task are available, we also provide a method to transfer
knowledge from the training tasks and exploit all available features for
prediction. However, we provide no guarantees for this method. We introduce a
practical method which allows for automatic inference of the above subset and
provide corresponding code. We present results on synthetic data sets and a
gene deletion data set
Learning Independent Causal Mechanisms
Statistical learning relies upon data sampled from a distribution, and we
usually do not care what actually generated it in the first place. From the
point of view of causal modeling, the structure of each distribution is induced
by physical mechanisms that give rise to dependences between observables.
Mechanisms, however, can be meaningful autonomous modules of generative models
that make sense beyond a particular entailed data distribution, lending
themselves to transfer between problems. We develop an algorithm to recover a
set of independent (inverse) mechanisms from a set of transformed data points.
The approach is unsupervised and based on a set of experts that compete for
data generated by the mechanisms, driving specialization. We analyze the
proposed method in a series of experiments on image data. Each expert learns to
map a subset of the transformed data back to a reference distribution. The
learned mechanisms generalize to novel domains. We discuss implications for
transfer learning and links to recent trends in generative modeling.Comment: ICML 201
- …