Dissociated Dipoles: Image representation via non-local comparisons

A fundamental question in visual neuroscience is how to represent image structure. The most common representational schemes rely on differential operators that compare adjacent image regions. While well-suited to encoding local relationships, such operators have significant drawbacks. Specifically, each filter's span is confounded with the size of its sub-fields, making it difficult to compare small regions across large distances. We find that such long-distance comparisons are more tolerant to common image transformations than purely local ones, suggesting they may provide a useful vocabulary for image encoding. . We introduce the "Dissociated Dipole," or "Sticks" operator, for encoding non-local image relationships. This operator de-couples filter span from sub-field size, enabling parametric movement between edge and region-based representation modes. We report on the perceptual plausibility of the operator, and the computational advantages of non-local encoding. Our results suggest that non-local encoding may be an effective scheme for representing image structure.

Investigating shape representation in area V4 with HMAX: Orientation and Grating selectivities

The question of how shape is represented is of central interest to understanding visual processing in cortex. While tuning properties of the cells in early part of the ventral visual stream, thought to be responsible for object recognition in the primate, are comparatively well understood, several different theories have been proposed regarding tuning in higher visual areas, such as V4. We used the model of object recognition in cortex presented by Riesenhuber and Poggio (1999), where more complex shape tuning in higher layers is the result of combining afferent inputs tuned to simpler features, and compared the tuning properties of model units in intermediate layers to those of V4 neurons from the literature. In particular, we investigated the issue of shape representation in visual area V1 and V4 using oriented bars and various types of gratings (polar, hyperbolic, and Cartesian), as used in several physiology experiments. Our computational model was able to reproduce several physiological findings, such as the broadening distribution of the orientation bandwidths and the emergence of a bias toward non-Cartesian stimuli. Interestingly, the simulation results suggest that some V4 neurons receive input from afferents with spatially separated receptive fields, leading to experimentally testable predictions. However, the simulations also show that the stimulus set of Cartesian and non-Cartesian gratings is not sufficiently complex to probe shape tuning in higher areas, necessitating the use of more complex stimulus sets.

Fictional characters' emotional state representation : What is its degree of specificity?

Resumen tomado de la publicaci??n

Monocular-based 3-D seafloor reconstruction and ortho-mosaicing by piecewise planar representation

Photo-mosaicing techniques have become popular for seafloor mapping in various marine science applications. However, the common methods cannot accurately map regions with high relief and topographical variations. Ortho-mosaicing borrowed from photogrammetry is an alternative technique that enables taking into account the 3-D shape of the terrain. A serious bottleneck is the volume of elevation information that needs to be estimated from the video data, fused, and processed for the generation of a composite ortho-photo that covers a relatively large seafloor area. We present a framework that combines the advantages of dense depth-map and 3-D feature estimation techniques based on visual motion cues. The main goal is to identify and reconstruct certain key terrain feature points that adequately represent the surface with minimal complexity in the form of piecewise planar patches. The proposed implementation utilizes local depth maps for feature selection, while tracking over several views enables 3-D reconstruction by bundle adjustment. Experimental results with synthetic and real data validate the effectiveness of the proposed approach

Response to instruction, English language learners and disproportionate representation : The role of assessment

Resumen tomado de la publicaci??n

Representation of Structure

Organic Molecules: Depiction of Structure - The Basics. Powerpoint presentation of A Level revision material for 1st year undergraduates written by Jeremy Hinks, School of Chemistry in 2002.

Introduction to Knowledge Representation

Focussing on Open Data and the need for cleaning data

Wikipedia and Gamergate

Abstract Introduction: This seminar is on the topic of "GamerGate", an international movement, ostensibly about "ethics in video game journalism" but which has become inextricably linked with extreme forms of online misogyny, rape and death threats towards women in the industry. It is of relevance to all Web science researchers, because it raises many issues of free speech, online governance, trolling and (not least) the representation of women in the tech industry. Our guest speaker (Mark Bernstein) is known for his criticism of the movement, and his work was featured in an article in the Guardian last week. He is a longtime collaborator in the field of hypertext and online media research, who co-orgainsed our annual international Web Science conference two years ago. Based in Boston, US, he will be speaking to us via Skype on Wednesday morning, to give us some background on the Gamergate phenomenon and to explain the recent developments regarding Wikipedia.

Crisis of political representation and democratization in Mexico: the generality and specificity of the case

This article attempts to assess the implications and the own character of the crisis of representation in Mexico. Once the topic framed and the long-term dynamics of Mexican political elites presented, this paper will attempt to understand why, despite the pluralization of the party system, there remain many questions about the truly democratic nature of the Mexican political system.

Socialización, educación y reproducción cultural : Bordieu y Bernstein.

Resumen tomado de la publicación

Basil Bernstein : memoria e historia.

Este artículo pretende rendir un homenaje a la obra de este sociólogo de la educación. Se analizan sus trabajos y sus más destacadas aportaciones teóricas enmarcadas en el contexto de las principales corrientes sociológicas, así como sus relaciones con los otros sociólogos relevantes. También se pone de manifiesto la influencia de su pensamiento en España, tanto en los aspectos teóricos como en la política educativa.

La sociolingüística de Basil Bernstein y sus implicaciones en el ámbito escolar.

Al analizar el pensamiento de Bernstein surgen grandes dificultades de carácter cuantitativo y cualitativo. Así, se analiza la obra de Bernstein con el fin de solucionar estos inconvenientes y de analizar el conjunto de planteamientos bernsteinianos, distinguiendo sus concepciones teóricas y las implicaciones de su teoría, es decir, los análisis que realiza de la escuela, ya que existe un paralelismo radical entre los códigos lingüísticos y los códigos escolares.

Educación, cultura y poder de clase : Basil Bernstein y la sociología neomarxista de la educación.

Se realiza un análisis crítico e histórico acerca de la postura de Bernstein en su obra, donde se hallan paralelismos en los argumentos avanzados por los estudios posmodernistas y postestructuralistas. Se destaca su reflexión sobre la naturaleza de la relación entre cultura y poder.

Construcción y validación de un instrumento diagnóstico para la representación cognitiva de la Orientación Psicopedagógica en Galicia. 'Construction and validation of a diagnostic instrument for the cognitive representation of the Guidance in Galicia'.

Resumen tomado de la publicación. Con el apoyo económico del departamento MIDE de la UNED