Pi: A Parallel Architecture Interface for Multi-Model Execution

This thesis defines Pi, a parallel architecture interface that separates model and machine issues, allowing them to be addressed independently. This provides greater flexibility for both the model and machine builder. Pi addresses a set of common parallel model requirements including low latency communication, fast task switching, low cost synchronization, efficient storage management, the ability to exploit locality, and efficient support for sequential code. Since Pi provides generic parallel operations, it can efficiently support many parallel programming models including hybrids of existing models. Pi also forms a basis of comparison for architectural components.

ADAM: A Decentralized Parallel Computer Architecture Featuring Fast Thread and Data Migration and a Uniform Hardware Abstraction

The furious pace of Moore's Law is driving computer architecture into a realm where the the speed of light is the dominant factor in system latencies. The number of clock cycles to span a chip are increasing, while the number of bits that can be accessed within a clock cycle is decreasing. Hence, it is becoming more difficult to hide latency. One alternative solution is to reduce latency by migrating threads and data, but the overhead of existing implementations has previously made migration an unserviceable solution so far. I present an architecture, implementation, and mechanisms that reduces the overhead of migration to the point where migration is a viable supplement to other latency hiding mechanisms, such as multithreading. The architecture is abstract, and presents programmers with a simple, uniform fine-grained multithreaded parallel programming model with implicit memory management. In other words, the spatial nature and implementation details (such as the number of processors) of a parallel machine are entirely hidden from the programmer. Compiler writers are encouraged to devise programming languages for the machine that guide a programmer to express their ideas in terms of objects, since objects exhibit an inherent physical locality of data and code. The machine implementation can then leverage this locality to automatically distribute data and threads across the physical machine by using a set of high performance migration mechanisms. An implementation of this architecture could migrate a null thread in 66 cycles -- over a factor of 1000 improvement over previous work. Performance also scales well; the time required to move a typical thread is only 4 to 5 times that of a null thread. Data migration performance is similar, and scales linearly with data block size. Since the performance of the migration mechanism is on par with that of an L2 cache, the implementation simulated in my work has no data caches and relies instead on multithreading and the migration mechanism to hide and reduce access latencies.

Visita a las Médulas : la explotación romana de las minas del Noroeste Peninsular : papel colonial de la Península Ibérica dentro de la economía del mundo romano.

Aplicar un método activo en la enseñanza de la Historia, a través del empleo de materiales diversos. Conseguir el correcto manejo de los materiales mediante el trabajo en equipo de los alumnos. Lograr que el alumno comprenda los conceptos de 'sociedad esclavista' y 'economía colonial'. Comprobar 'in situ', mediante la visita a los restos mineros de las Médulas, las conclusiones elaboradas en clase a partir de los materiales de trabajo estudiados. ¿Cómo enseñar un tema de Historia utilizando un método activo?. En primer lugar se estudia la conquista del Norte y Noroeste peninsular, cómo se establece la infraestructura adecuada para la explotación minera, las características de las explotaciones auríferas romanas en el Noroeste peninsular y se realiza una evaluación de estas explotaciones (cronología y causas de su decadencia). A continuación se describen detalladamente los restos mineros de las Médulas. Propone el uso de materiales como textos antiguos y contemporáneos, catálogos y mapas; visita a las Médulas; elaboración por los alumnos de un dossier con todo el trabajo realizado, así como del material gráfico que hayan podido obtener durante la visita. Se realiza una descripción de las Médulas tanto desde el punto de vista de su evolución histórica como de su estado actual. Se aportan materiales y ejercicios para utilizar en el aula. Da una descripción de cómo trabajar en clase con diversos materiales (que también aporta), como pueden ser: textos antiguos, mapas, planos, fotos y esquemas cronológicos. No obstante, no deja constancia de que dichos materiales hayan sido aplicados directamente con un grupo de alumnos. Fecha finalización tomada del código del documento.

Space System Architecture: Final Report of SSPARC: the Space Systems, Policy, and Architecture Research Consortium (Thrust I and II)

The Space Systems, Policy and Architecture Research Consortium (SSPARC) was formed to make substantial progress on problems of national importance. The goals of SSPARC were to: • Provide technologies and methods that will allow the creation of flexible, upgradable space systems, • Create a “clean sheet” approach to space systems architecture determination and design, including the incorporation of risk, uncertainty, and flexibility issues, and • Consider the impact of national space policy on the above. This report covers the last two goals, and demonstrates that the effort was largely successful.

Fast Sorting on a Distributed-Memory Architecture

We consider the often-studied problem of sorting, for a parallel computer. Given an input array distributed evenly over p processors, the task is to compute the sorted output array, also distributed over the p processors. Many existing algorithms take the approach of approximately load-balancing the output, leaving each processor with Θ(n/p) elements. However, in many cases, approximate load-balancing leads to inefficiencies in both the sorting itself and in further uses of the data after sorting. We provide a deterministic parallel sorting algorithm that uses parallel selection to produce any output distribution exactly, particularly one that is perfectly load-balanced. Furthermore, when using a comparison sort, this algorithm is 1-optimal in both computation and communication. We provide an empirical study that illustrates the efficiency of exact data splitting, and shows an improvement over two sample sort algorithms.

VLSI architecture for an Underwater Robot Vision System

It is well known that image processing requires a huge amount of computation, mainly at low level processing where the algorithms are dealing with a great number of data-pixel. One of the solutions to estimate motions involves detection of the correspondences between two images. For normalised correlation criteria, previous experiments shown that the result is not altered in presence of nonuniform illumination. Usually, hardware for motion estimation has been limited to simple correlation criteria. The main goal of this paper is to propose a VLSI architecture for motion estimation using a matching criteria more complex than Sum of Absolute Differences (SAD) criteria. Today hardware devices provide many facilities for the integration of more and more complex designs as well as the possibility to easily communicate with general purpose processors

Proposal of a parallel architecture for a motion detection algorithm

This paper proposes a parallel architecture for estimation of the motion of an underwater robot. It is well known that image processing requires a huge amount of computation, mainly at low-level processing where the algorithms are dealing with a great number of data. In a motion estimation algorithm, correspondences between two images have to be solved at the low level. In the underwater imaging, normalised correlation can be a solution in the presence of non-uniform illumination. Due to its regular processing scheme, parallel implementation of the correspondence problem can be an adequate approach to reduce the computation time. Taking into consideration the complexity of the normalised correlation criteria, a new approach using parallel organisation of every processor from the architecture is proposed

On AUV control architecture

This paper surveys control architectures proposed in the literature and describes a control architecture that is being developed for a semi-autonomous underwater vehicle for intervention missions (SAUVIM) at the University of Hawaii. Conceived as hybrid, this architecture has been organized in three layers: planning, control and execution. The mission is planned with a sequence of subgoals. Each subgoal has a related task supervisor responsible for arranging a set of pre-programmed task modules in order to achieve the subgoal. Task modules are the key concept of the architecture. They are the main building blocks and can be dynamically re-arranged by the task supervisor. In our architecture, deliberation takes place at the planning layer while reaction is dealt through the parallel execution of the task modules. Hence, the system presents both a hierarchical and an heterarchical decomposition, being able to show a predictable response while keeping rapid reactivity to the dynamic environment

All-Optical Label Stacking: Easing the Trade-offs Between Routing and Architecture Cost in All-Optical Packet Switching

All-optical label swapping (AOLS) forms a key technology towards the implementation of all-optical packet switching nodes (AOPS) for the future optical Internet. The capital expenditures of the deployment of AOLS increases with the size of the label spaces (i.e. the number of used labels), since a special optical device is needed for each recognized label on every node. Label space sizes are affected by the way in which demands are routed. For instance, while shortest-path routing leads to the usage of fewer labels but high link utilization, minimum interference routing leads to the opposite. This paper studies all-optical label stacking (AOLStack), which is an extension of the AOLS architecture. AOLStack aims at reducing label spaces while easing the compromise with link utilization. In this paper, an integer lineal program is proposed with the objective of analyzing the softening of the aforementioned trade-off due to AOLStack. Furthermore, a heuristic aiming at finding good solutions in polynomial-time is proposed as well. Simulation results show that AOLStack either a) reduces the label spaces with a low increase in the link utilization or, similarly, b) uses better the residual bandwidth to decrease the number of labels even more

Poder y distinción colonial: las fiestas del virrey presente y el rey ausente Nueva Granada 1770-1800

El propósito de este artículo es identificar y analizar algunos aspectos de la versión neogranadina de las fiestas de recibimiento virreinal: los mecanismos internos de poder y de distinción colonial, y las dinámicas de dominio que se ponían en juego entre la Metrópoli y el Virreinato de la Nueva Granada a finales del siglo XVIII. Para esto se intentará hacer una aproximación desde la realidad propia del territorio colonial, del impacto que tuvieron estas celebraciones en un Virreinato desprovisto de grandes riquezas y con una capacidad de gasto inferior a otros, como el de Nueva España o el Perú. Así, lejos de constituirse una réplica del modelo original de las ceremonias festivas europeas, los recibimientos virreinales neogranadinos fueron producto de la apropiación de algunas fórmulas festivas pero, sobretodo, se adaptaron, se acomodaron a sus escasas rentas y algunas veces, incluso, las autoridades locales y los habitantes rechazaron o cuestionaron vivamente estas ceremonias.

What is the Web? The Web Architecture

The Introductory Lecture is a discussion about "What is the Web". It involves lots of calling out TLAs and writing them on the blackboard, dividing things into servers, clients, protocols, formats, and the punchline is that the one unique and novel thing about the web is the hypertext link. This follows naturally into the Web architecture - the answer to the question "what is the web".

Análisis de la renovación urbana como estrategia de recuperación del centro histórico de bogotá : estudio de caso barrio Santa Bárbara Colonial (Nueva Santa Fé), en el periodo 1976-2000

El presente estudio de caso se propuso analizar la renovación urbana como estrategia de recuperación del centro histórico de Bogotá, utilizando como objeto de investigación, el proceso de renovación urbana que atravesó el Barrio Santa Bárbara Colonial, hoy conocido como Nueva Santa Fe, en el período 1976 (fecha de planteamiento del proyecto) a 2000 (año en el que se implementa el P.O.T), lo que significa nuevas condiciones en términos urbanos para ejecutar proyectos dentro de la ciudad), para lo cual se va a utilizar el concepto de vivienda, dentro de la renovación urbana, como variable que servirá de hilo conductor en el desarrollo del tema. El concepto de renovación que concierne a esta investigación está enmarcado en la década de los 70s y 80s, para lo cual se hace una breve referencia a la década de los 50s y 60s como antecedente de la creciente tendencia que tuvo la renovación urbana en Europa, continente que ha marcado una fuerte influencia en Latinoamérica y a su vez en Colombia. Con base a dicha estructuración, se da cuenta del tipo de investigación a desarrollar, una investigación cualitativa interesada en reflexionar sobre la forma en que se desarrolló la renovación urbana en el sector, haciendo evidente sus falencias y más adelante, los errores que se siguen cometiendo en los planteamientos actuales que tienen que ver con este tratamiento.

COMP6218 Web Architecture - Web Content Formats

Plain Text - ASCII, Unicode, UTF-8 Content Formats - XML-based formats (RSS, MathML, SVG, Office) + PDF Text based data formats: CSV, JSON

Enterprise Architecture notes/white papers

A collection of notes and white papers regarding Enterprise Architecture