Procedures as a Representation for Data in a Computer Program for Understanding Natural Language

This paper describes a system for the computer understanding of English. The system answers questions, executes commands, and accepts information in normal English dialog. It uses semantic information and context to understand discourse and to disambiguate sentences. It combines a complete syntactic analysis of each sentence with a "heuristic understander" which uses different kinds of information about a sentence, other parts of the discourse, and general information about the world in deciding what the sentence means. It is based on the belief that a computer cannot deal reasonably with language unless it can "understand" the subject it is discussing. The program is given a detailed model of the knowledge needed by a simple robot having only a hand and an eye. We can give it instructions to manipulate toy objects, interrogate it about the scene, and give it information it will use in deduction. In addition to knowing the properties of toy objects, the program has a simple model of its own mentality. It can remember and discuss its plans and actions as well as carry them out. It enters into a dialog with a person, responding to English sentences with actions and English replies, and asking for clarification when its heuristic programs cannot understand a sentence through use of context and physical knowledge.

Representation and Detection of Shapes in Images

We present a set of techniques that can be used to represent and detect shapes in images. Our methods revolve around a particular shape representation based on the description of objects using triangulated polygons. This representation is similar to the medial axis transform and has important properties from a computational perspective. The first problem we consider is the detection of non-rigid objects in images using deformable models. We present an efficient algorithm to solve this problem in a wide range of situations, and show examples in both natural and medical images. We also consider the problem of learning an accurate non-rigid shape model for a class of objects from examples. We show how to learn good models while constraining them to the form required by the detection algorithm. Finally, we consider the problem of low-level image segmentation and grouping. We describe a stochastic grammar that generates arbitrary triangulated polygons while capturing Gestalt principles of shape regularity. This grammar is used as a prior model over random shapes in a low level algorithm that detects objects in images.

A Note on Object Class Representation and Categorical Perception

We present a novel scheme ("Categorical Basis Functions", CBF) for object class representation in the brain and contrast it to the "Chorus of Prototypes" scheme recently proposed by Edelman. The power and flexibility of CBF is demonstrated in two examples. CBF is then applied to investigate the phenomenon of Categorical Perception, in particular the finding by Bulthoff et al. (1998) of categorization of faces by gender without corresponding Categorical Perception. Here, CBF makes predictions that can be tested in a psychophysical experiment. Finally, experiments are suggested to further test CBF.

Stimulus Simplification and Object Representation: A Modeling Study

Tsunoda et al. (2001) recently studied the nature of object representation in monkey inferotemporal cortex using a combination of optical imaging and extracellular recordings. In particular, they examined IT neuron responses to complex natural objects and "simplified" versions thereof. In that study, in 42% of the cases, optical imaging revealed a decrease in the number of activation patches in IT as stimuli were "simplified". However, in 58% of the cases, "simplification" of the stimuli actually led to the appearance of additional activation patches in IT. Based on these results, the authors propose a scheme in which an object is represented by combinations of active and inactive columns coding for individual features. We examine the patterns of activation caused by the same stimuli as used by Tsunoda et al. in our model of object recognition in cortex (Riesenhuber 99). We find that object-tuned units can show a pattern of appearance and disappearance of features identical to the experiment. Thus, the data of Tsunoda et al. appear to be in quantitative agreement with a simple object-based representation in which an object's identity is coded by its similarities to reference objects. Moreover, the agreement of simulations and experiment suggests that the simplification procedure used by Tsunoda (2001) is not necessarily an accurate method to determine neuronal tuning.

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.

Análisis sectorial del GSED

El Grupo Social Empresarial de la Defensa GSED es el ente encargado de dirigir y orientar las políticas corporativas de las empresas que constituyen el Ministerio de Defensa, con el único fin de contribuir paz y seguridad en el territorio Colombiano. Aunque el grupo no es reconocido como tal sino por las empresas que lo componen se define al grupo para la comprensión de los lectores del presente trabajo. De igual forma se explica y analiza el objeto y función de las mismas Por medio de un análisis de la estructura del grupo, abarcando ejes como el administrativo y financiero se determina el impacto del mismo y su importancia en la economía del país como Grupo Empresarial.

Acord de la conferència sectorial en matèria de serveis socials. Desplegament de la Llei de Dependència. 'Acuerdo de la conferencia sectorial en materia de servicios sociales. Despliegue de la Ley de Dependencia'.

Resumen tomado de la publicación

Análisis del plan sectorial de educación “Bogotá: una gran escuela” y sus resultados en materia social educativa de la ciudad, periodo 2004-2008

La educación es un factor fundamental e indispensable para la formación y calidad de vida de todo individuo, su aplicabilidad vista como un derecho y bien fundamental para las personas debe tener la prioridad e importancia merecida por parte de los Estados, en pro del desarrollo no solo de los individuos sino de la sociedad como tal, pues la mejor forma de enriquecerla es a través de libros, colegios, computadores y demás elementos que pertenecen a una verdadera calidad social educativa. En ese sentido, se plantea un estudio de caso del plan sectorial de educación “Bogotá: una grande escuela” en el periodo 2004-2008

Hacia la definición y el dimensionamiento de un sistema distrital de información en discapacidad. Primera fase sectorial : Secretaría Distrital de Salud

En cumplimiento de lo estipulado constitucional y normativamente en materia de discapacidad, el Distrito Capital genera para el año 2001 el Plan Distrital de Discapacidad 2001- 2005, que propone mejorar la calidad de vida de las personas con discapacidad y sus familias, a través de la búsqueda de autonomía, independencia e inclusión comunitaria, por medio de dos grandes objetivos: 1) la generación y ajuste de políticas públicas y 2) el desarrollo de la prestación de servicios en relación con las necesidades de esta población. Estos dos objetivos dan lugar a siete líneas de intervención: promoción y prevención, atención en salud, re/habilitación, educación, accesibilidad, vida laboral y redes de apoyo.2 En consonancia con el desarrollo de estas líneas de intervención, se planteó la necesidad de contar con el apoyo de la Facultad de Rehabilitación y Desarrollo Humano de la Universidad del Rosario, a fin de contribuir con el desarrollo del programa de prevención y manejo de la discapacidad de la Secretaría Distrital de Salud en los componentes de tecnología, sistema de información, fortalecimiento de la rehabilitación institucional e inclusión social.