8 research outputs found

    Radiation Hydrodynamic Models and Simulated Observations of Radiative Feedback in Star Forming Regions

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    This thesis details the development of the radiation transport code torus for radiation hydrodynamic applications and its subsequent use in investigating problems regarding radiative feedback. The code couples Monte Carlo photoionization with grid-based hydrodynamics and has the advantage that all of the features available to a dedicated radiation transport code are at its disposal in RHD applications. I discuss the development of the code, including the hydrodynamics scheme, the adaptive mesh refinement (AMR) framework and the coupling of radiation transport with hydrodynamics. Extensive testing of the resulting code is also presented. The main application involves the study of radiatively driven implosion (RDI), a mechanism where the expanding ionized region about a massive star impacts nearby clumps, potentially triggering star formation. Firstly I investigate the way in which the radiation field is treated, isolating the relative impacts of polychromatic and diffuse field radiation on the evolution of radiation hydrodynamic RDI models. I also produce synthetic SEDs, radio, Hα and forbidden line images of the bright rimmed clouds (BRCs) resulting from the RDI models, on which I perform standard diagnostics that are used by observers to obtain the cloud conditions. I test the accuracy of the diagnostics and show that considering the pressure difference between the neutral cloud and surrounding ionized layer can be used to infer whether or not RDI is occurring. Finally I use more synthetic observations to investigate the accuracy of molecular line diagnostics and the nature of line profiles of BRCs. I show that the previously unexplained lack of dominant blue-asymmetry (a blue-asymmetry is the expected signature of a collapsing cloud) in the line profiles of BRCs can be explained by the shell of material, swept up by the expanding ionized region, that drives into the cloud. The work in this thesis combines to help resolve the difficulties in understanding radiative feedback, which is a non–linear process that happens on small astrophysical timescales, by improving numerical models and the way in which they are compared with observations

    Respawn

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    In Respawn Colin Milburn examines the connections between video games, hacking, and science fiction that galvanize technological activism and technological communities. Discussing a wide range of games, from Portal and Final Fantasy VII to Super Mario Sunshine and Shadow of the Colossus, Milburn illustrates how they impact the lives of gamers and non-gamers alike. They also serve as resources for critique, resistance, and insurgency, offering a space for players and hacktivist groups such as Anonymous to challenge obstinate systems and experiment with alternative futures. Providing an essential walkthrough guide to our digital culture and its high-tech controversies, Milburn shows how games and playable media spawn new modes of engagement in a computerized world

    Generative Mesh Modeling

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    Generative Modeling is an alternative approach for the description of three-dimensional shape. The basic idea is to represent a model not as usual by an agglomeration of geometric primitives (triangles, point clouds, NURBS patches), but by functions. The paradigm change from objects to operations allows for a procedural representation of procedural shapes, such as most man-made objects. Instead of storing only the result of a 3D construction, the construction process itself is stored in a model file. The generative approach opens truly new perspectives in many ways, among others also for 3D knowledge management. It permits for instance to resort to a repository of already solved modeling problems, in order to re-use this knowledge also in different, slightly varied situations. The construction knowledge can be collected in digital libraries containing domain-specific parametric modeling tools. A concrete realization of this approach is a new general description language for 3D models, the "Generative Modeling Language" GML. As a Turing-complete "shape programming language" it is a basis of existing, primitv based 3D model formats. Together with its Runtime engine the GML permits - to store highly complex 3D models in a compact form, - to evaluate the description within fractions of a second, - to adaptively tesselate and to interactively display the model, - and even to change the models high-level parameters at runtime.Die generative Modellierung ist ein alternativer Ansatz zur Beschreibung von dreidimensionaler Form. Zugrunde liegt die Idee, ein Modell nicht wie üblich durch eine Ansammlung geometrischer Primitive (Dreiecke, Punkte, NURBS-Patches) zu beschreiben, sondern durch Funktionen. Der Paradigmenwechsel von Objekten zu Geometrie-erzeugenden Operationen ermöglicht es, prozedurale Modelle auch prozedural zu repräsentieren. Statt das Resultat eines 3D-Konstruktionsprozesses zu speichern, kann so der Konstruktionsprozess selber repräsentiert werden. Der generative Ansatz eröffnet unter anderem gänzlich neue Perspektiven für das Wissensmanagement im 3D-Bereich. Er ermöglicht etwa, auf einen Fundus bereits gelöster Konstruktions-Aufgaben zurückzugreifen, um sie in ähnlichen, aber leicht variierten Situationen wiederverwenden zu können. Das Konstruktions-Wissen kann dazu in Form von Bibliotheken parametrisierter, Domänen-spezifischer Modellier-Werkzeuge gesammelt werden. Konkret wird dazu eine neue allgemeine Modell-Beschreibungs-Sprache vorgeschlagen, die "Generative Modeling Language" GML. Als Turing-mächtige "Programmiersprache für Form" stellt sie eine echte Verallgemeinerung existierender Primitiv-basierter 3D-Modellformate dar. Zusammen mit ihrer Runtime-Engine erlaubt die GML, - hochkomplexe 3D-Objekte extrem kompakt zu beschreiben, - die Beschreibung innerhalb von Sekundenbruchteilen auszuwerten, - das Modell adaptiv darzustellen und interaktiv zu betrachten, - und die Modell-Parameter interaktiv zu verändern

    Transformando la educación a través del conocimiento

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    La educación es uno de los motores de transformación social más poderoso que existen y ejerce como instrumento de cohesión social, igualando las diferencias de género, etnia, situación económica, etc. La investigación educativa es, pues, una actividad estratégica: las mejoras en educación repercuten en el conjunto de la sociedad. Es en este contexto donde se sitúa el presente volumen, titulado Transformando la educación a través del conocimiento. Esta obra recoge un total de 127 capítulos con experiencias de investigación teórica y aplicación práctica sobre experiencias concretas de innovación docente. Las contribuciones, centradas en áreas educativas diversas (educación lingüística, artística, en ciencias sociales y ambientales, etc.) y de diferentes niveles educativos (tanto de los preuniversitarios, como de educación superior), tienen en común que ofrecen una mirada renovada sobre los retos que debe enfrentar la educación actual: la inclusión educativa, la integración de las TIC en la educación, la transición entre diferentes niveles educativos, la igualdad de género o la educación emocional son, entre muchos otros, algunos de los temas abordados. El presente volumen, pues, quiere contribuir a la difusión de las algunas de las aportaciones más recientes que contribuyen al progreso del conocimiento sobre los procesos de enseñanza-aprendizaje en la sociedad actual
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