2,355 research outputs found
Scalar-Vector Bootstrap
We work out all of the details required for implementation of the conformal
bootstrap program applied to the four-point function of two scalars and two
vectors in an abstract conformal field theory in arbitrary dimension. This
includes a review of which tensor structures make appearances, a construction
of the projectors onto the required mixed symmetry representations, and a
computation of the conformal blocks for all possible operators which can be
exchanged. These blocks are presented as differential operators acting upon the
previously known scalar conformal blocks. Finally, we set up the bootstrap
equations which implement crossing symmetry. Special attention is given to the
case of conserved vectors, where several simplifications occur.Comment: 76 pages, v3 moved several details into appendices, expanded
discussion of mixed symmetry projecto
Geodesic Diagrams, Gravitational Interactions & OPE Structures
We give a systematic procedure to evaluate conformal partial waves involving
symmetric tensors for an arbitrary CFT using geodesic Witten diagrams in
AdS. Using this procedure we discuss how to draw a line between the
tensor structures in the CFT and cubic interactions in AdS. We contrast this
map to known results using three-point Witten diagrams: the maps obtained via
volume versus geodesic integrals differ. Despite these differences, we show how
to decompose four-point exchange Witten diagrams in terms of geodesic diagrams,
and we discuss the product expansion of local bulk fields in AdS.Comment: typos corrected, references adde
Multimodal stereo from thermal infrared and visible spectrum
Recent advances in thermal infrared imaging (LWIR) has allowed its use in applications beyond of the military domain. Nowadays, this new family of sensors is included in different technical and scientific applications. They offer features that facilitate tasks, such as detection of pedestrians, hot spots, differences in temperature, among others, which can significantly improve the performance of a system where the persons are expected to play the principal role. For instance, video surveillance applications, monitoring, and pedestrian detection. During the dissertation the next question is stated: \textit{Could a couple of sensors measuring different bands of the electromagnetic spectrum, as the visible and thermal infrared, be used to extract depth information?} Although it is a complex question, we shows that a system of these characteristics is possible as well as their advantages, drawbacks, and potential opportunities. In this research an experimental study that compares different cost functions and matching approaches is performed, in order to build a multimodal stereovision system. Furthermore, the common problems in infrared/visible stereo, specially in the outdoor scenes are identified. Our framework summarizes the architecture of a generic stereo algorithm, at different levels: computational, functional, and structural, which can be extended toward high-level fusion (semantic) and high-order (prior). The proposed framework is intended to explore novel multimodal stereo matching approaches, going from sparse to dense representations (both disparity and depth maps). Moreover, context information is added in form of priors and assumptions. Finally, the dissertation shows a promissory way toward the integration of multiple sensors for recovering three-dimensional information
Represalia Ejemplar 109 Brigada Mixta
Depto. de Historia Moderna y ContemporáneaFac. de Geografía e Historiaunpu
Standards of Productive Projects in Military Correctional Centers
El presente proyecto consiste en Reglamentar a los Centro Penitenciarios Militares, en donde se normatiza el reglamento para el manejo de recursos generados en los establecimientos de reclusión.This project is to regulate the Military Correctional Center, where the rules for the management of resources generated in the prisons is formulating standards
¿Es la autoestima una variable relevante para los programas de prevención del inicio temprano de actividad sexual?
This article presents the results of three non experimental, correlational and crossectional studies. The studies respond to the questions that Vargas-Trujillo, Gambara and Botella (submitted for publication) proposed at the end of a meta-analytic review conducted to examine the difference in self-esteem between adolescents with high and low sexual risk activity. The results showed that self-esteem is not a relevant variable for prevention programs directed towards high school students in Colombia. In contrast, non virgin adolescents and those who have initiated sexual intercourse at early age are significantly different in levels of self-efficacy and perceived social norms than their non sexual activity counterparts.Se presentan los resultados de tres estudios transversales, no experimentales, correlacionales que se realizaron para responder a las preguntas que proponen Vargas Trujillo, Gambara y Botella (sometido a publicación) al final del estudio meta-analítico que realizaron para examinar la relación de la autoestima con el inicio de actividad sexual en la adolescencia. Los hallazgos indican que en Colombia, al menos en el grupo de adolescentes vinculados al sistema educativo en Bogotá, la autoestima no es una variable relevante para los programas de prevención del inicio temprano de actividad sexual. Los análisis sugieren que la autoeficacia y el contexto normativo en el que se desarrollan los adolescentes sí establecen diferencias significativas en el estatus sexual y en la edad a la que se tienen relaciones sexuales por primera vez
Materiales provenientes del reciclamiento de envases de Tetra Pak y su uso en concreto
Son escasos los estudios que involucran el uso de los materiales de reciclo de envases de Tetra Pak. No obstante, se ha estudiado la viabilidad del uso de polietleno de baja densidad (LDPE) y el aluminio reciclados de envases Tetra Pak para la fabricación de tableros rígidos utlizando una prensa caliente. En este capítulo se evaluó el efecto de las partículas de Tetra Pak en concretos poliméricos. Se realizaron ensayos de compresión y fexión, así como el cálculo del módulo de Young; con la finalidad de conocer el efecto de las partículas en la deformación
VIOLENCIA Y RECONFIGURACIÓN TERRITORIAL EN EL ÁREA METROPOLITANA DE BUENOS AIRES
This work aims at analyzing the territorial reconfiguration processes that were deployed from the structural changes begin to be imposed for three decades in our continent. It should be noted that primary and secondary sources used. Thus, the statistics illustrate the macro process, while allowing interviews to collect the voice of the actors on that process. The conclusions highlight of our work argue that the urban area has become a progressive peripheral centrality as a new social space of the subaltern classes. There is a process of collective action from the popular sectors, seeking to solve the problem of habitat, place the territory in the center of the debate on the reorganization of these sectors
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