Shared Arrangements: practical inter-query sharing for streaming dataflows

Current systems for data-parallel, incremental processing and view maintenance over high-rate streams isolate the execution of independent queries. This creates unwanted redundancy and overhead in the presence of concurrent incrementally maintained queries: each query must independently maintain the same indexed state over the same input streams, and new queries must build this state from scratch before they can begin to emit their first results. This paper introduces shared arrangements: indexed views of maintained state that allow concurrent queries to reuse the same in-memory state without compromising data-parallel performance and scaling. We implement shared arrangements in a modern stream processor and show order-of-magnitude improvements in query response time and resource consumption for interactive queries against high-throughput streams, while also significantly improving performance in other domains including business analytics, graph processing, and program analysis

Some Developments in Flexible Regression Modelling

In this thesis we focus on the exible regression modelling with several applications to the insurance eld. We give our contribution to the exible regression modelling by the introduction and validation of some new models. As our aim was to give a contribution useful from the point of view of an insurance company, we did not focus only on theoretical aspects, but we also took care of practical ones. We rst introduce the class of exible regression models, highlighting strengths and drawbacks arising in their practical use, with the aim of pro- vide the tools necessary to the sequent steps. We then introduced GeDS model, a non-parametric approach that is based on a geometrical interpretation of the placement of the knots of a polynomial spline. We show that this model, in some cases, is able to out- perform other exible models. Some properties of the estimates obtained via GeDS regression are then studied, by setting the framework to obtain asymptotically correct con - dence intervals and a consistent version of the likelihood ratio test. Some e orts were also spent in order implement in statistical software this regression model. Hence we explain the features of the software devel- oped. In this thesis we present also an application of exible regression models in non-life ratemaking. We developed some models that can be applied in this framework, returning estimates as accurate as possible, but, at the same time, simple and understandable. We introduce some models that combine together other more simple ones and we show their performances through simulation studies based rst on a theoretical example and then on a more realistic one. We found that they perform better than other models adopted in common practice. Simulation studies are applied also for this purposeopenDottorato di ricerca in Scienze manageriali e atturialiopenLattuada, Andre

Performance estimation of embedded software with confidence levels

Since time constraints are a very critical aspect of an embedded system, performance evaluation can not be postponed to the end of the design flow, but it has to be introduced since its early stages. Estimation techniques based on mathematical models are usually preferred during this phase since they provide quite accurate estimation of the application performance in a fast way. However, the estimation error has to be considered during design space exploration to evaluate if a solution can be accepted (e.g., by discarding solutions whose estimated time is too close to constraint). Evaluate if the possible error can be significant analyzing a punctual estimation is not a trivial task. In this paper we propose a methodology, based on statistical analysis, that provides a prediction interval on the estimation and a confidence level on meeting a time constraint. This information can drive design space exploration reducing the number of solutions to be validated. The results show how the produced intervals effectively capture the estimation error introduced by a linear model

Rural development policies in Argentina. Concepts, context and changes

La problemática del desarrollo tiene una extensa trayectoria en su construcción como concepto y como estrategia de intervención en la sociedad. Las contribuciones surgidas de claustros univer-sitarios anglosajones (pero también latinoameri-canos) abonaron extensos y profundos debates académicos, así como el diseño de las estrate-gias de intervención de gobiernos y organismos de financiamiento internacional. El contenido de este artículo se propone dar cuenta del procesode construcción del concepto de desarrollo y su evolución en diferentes contextos históricos, su estrecha vinculación con las políticas de trans-formación de las comunidades rurales y el modo en que esas corrientes de pensamiento influye-ron en los programas de desarrollo rural lleva-dos a cabo en la Argentina entre 1984 y 2013. En cuanto a la influencia de esas ideas en los programas del desarrollo rural en la Argentina, se ha realizado un análisis comparativo diacró-nico basado en fuentes primarias. La presencia del Fondo Internacional de Desarrollo Agrícola (FIDA) como organismo internacional de finan-ciamiento de programas de desarrollo rural en la Argentina, desde sus primeras experiencias a fi-nes de la década de 1980 hasta la actualidad, po-sibilitó el análisis de los documentos de diseño y reorientación de los programas elaborados en diferentes contextos históricos. A partir de este material se analizan los cambios ocurridos en la definición de los objetos del desarrollo, la pobla-ción objetivo, los instrumentos priorizados, y la estructura a cargo de la definición y gestión de la política de desarrollo rural.The subject of development has a long history in its constitution as a concept and as a strategy to intervene society. Contributions from Anglo-Saxon and Latin American universities have given place extensive academic discussion, but have also helped design strategies to intervene governments and international funding agencies. The purpose of this article is to outline the process through which development as a concept is assembled and its evolution in different historical contexts, taking into account its close connection to government policies focused on the transformation of rural communities, and the way those ideas have influenced rural development programs conducted in Argentina from 1984 to 2013. This paper presents a diachronic and comparative analysis based on primary sources. The presence of the Fondo Internacional de Desarrollo Agrícola (FIDA)and other international funding agencies of rural development programs, since their first experiences in the late 1980s to the present, has made it possible to examine the design and reorientation of the programs conceived in different historical contexts. Based on this material, the changes in the definition of the objects and subjects of rural development are analyzed in order to contribute to the definition and management of a rural development policy.Fil: Lattuada, Mario Jose. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Code transformations based on speculative SDC scheduling

Code motion and speculations are usually exploited in the High Level Synthesis of control dominated applications to improve the performances of the synthesized designs. Selecting the transformations to be applied is not a trivial task: their effects can indeed indirectly spread across the whole design, potentially worsening the quality of the results. In this paper we propose a code transformation flow, based on a new extension of the System of Difference Constraints (SDC) scheduling algorithm, which introduces a large number of transformations, whose profitability is guaranteed by SDC formulation. Experimental results show that the proposed technique in average reduces the execution time of control dominated applications by 37% with respect to a commercial tool without increasing the area usage

Exploiting Vectorization in High Level Synthesis of Nested Irregular Loops

Synthesis of DoAll loops is a key aspect of High Level Synthesis since they allow to easily exploit the potential parallelism provided by programmable devices. This type of parallelism can be implemented in several ways: by duplicating the implementation of body loop, by exploiting loop pipelining or by applying vectorization. In this paper a methodology for the synthesis of nested irregular DoAll loops based on outer vectorization is proposed. The methodology transforms the intermediate representation of the DoAll loop to introduce vectorization and it can be easily integrated in existing state of the art High Level Synthesis flows since does not require any modification in the rest of the flow. Vectorization is not limited to perfectly nested countable loops: conditional constructs and loops with variable number of iterations are supported. Experimental results on parallel benchmarks show that the generated parallel accelerators have significant speed-up with limited penalties in terms of resource usage and frequency decrement

Performance modeling of embedded applications with zero architectural knowledge

Performance estimation is a key step in the development of an embedded system. Normally, the performance evaluation is performed using a simulator or a performance mathematical model of the target architecture. However, both these approaches are usually based on the knowledge of the architectural details of the target. In this paper we present a methodology for automatically building an analytical model to estimate the performance of an application on a generic processor without requiring any information about the processor architecture but the one provided by the GNU GCC Intermediate Representation. The proposed methodology exploits the linear regression technique based on an application analysis performed on the Register Transfer Level internal representation of the GNU GCC compiler. The benefits of working with this type of model and with this intermediate representation are three: we take into account most of the compiler optimizations, we implicitly consider some architectural characteristics of the target processor and we can easily estimate the performance of portions of the specification. We validate our approach by evaluating with cross-validation technique the accuracy and the generality of the performance models built for the ARM926EJ-S and the LEON3 processor

Las relaciones con la prensa en el entorno digital. Nuevas prácticas y herramientas

The new paradigm in horizontal communication and dialogue with audiences, together with technological development and the spread of digital and multimedia tools, have not only had a big impact but also reformulated the management of communication Professionals and, as a result, in the areas of communication companies, organizations and institutions. These facts have deep implications in the profile of communication professionals and in the way in which they carry out specific managements that emerge from the area, such as the management of Media Relations and the Media.In recent years, there appeared some elements to take into account, since they determineand feature the new dynamics in which this management and link-up are developed, which are:immediacy, the synthesis of content which precedes all information delivery, the prevalence of image to text, new resources such as infographics, videos, links and connections between different social networks. Thus, new media formats are added to traditional messaging platforms which are intended to provide information of the company, organization or institution to journalists swiftly and according to the current environment. We are talking about new dynamics, logics, tools and platforms which do not replace the previous ones but are integrated in a distinct, unique and current mixture as befits a time in full deployment. Thus, in this context, let´s take into account certain considerations when circulating information to the press: 1) it is a time characterized by information surplus; 2) attention is divided over multiple screens and mobile devices; 3) the paradox likes inthe fact that consumption is rationed to everything which, in a few seconds is capable of catching attention and telling a story; 4) a story that can be possibly reduced to an image or to a high impact audiovisual format including additional material in other related digital formats, integrated into a multimedia platform, and 5) abilities and skills linked to digital design and new technologies such as aptitude to interpret and follow new trends in content on social network are required.Within this framework, communicators find a new challenge: learning to manage communication and transmit messages to the press with a new model that presents new variables in an ever-changing context. In this way, we are introduced to new elements that rethink the practices and the tools traditionally used in the management of Media Relations and the Media. The goal of the present research work was to revise, gather and introduce these new modes and options of tools to transmit informationto this key audience, because of the scope and visibility that it provides to the messages of the company or organization.El nuevo paradigma de la comunicación horizontal y del diálogo con las audiencias, junto con el desarrollo de la tecnología y la proliferación de herramientas digitales y multimedia, no solo han impactado sino también reformulado la gestión del profesional de la comunicación y, en consecuencia, de las áreas de comunicación de las empresas, organizaciones e instituciones. Esto tiene implicancias profundas en el perfil del profesional de comunicación y en el modo en que se llevan a cabo las gestiones específicas que se desprenden del área, como la gestión de las relaciones con la prensa y los medios de comunicación. En los últimos años surgieron elementos a tener en cuenta, que condicionan y delinean la nueva dinámica en que se desarrolla esta gestión y vinculación: la inmediatez, la síntesis de contenido que antecede toda entrega de información, la prevalencia de imágenes a textos, los nuevos recursos audiovisuales como infografías, videos, audios, enlaces y conexiones entre las distintas redes sociales. Así, se suman a las plataformas tradicionales de transmisión de mensajes nuevos formatos multimedia destinados a entregar la información de la empresa, organización o institución a los periodistas de manera ágil y acorde al entorno actual. Se trata de nuevas dinámicas, lógicas, herramientas y plataformas que no reemplazan a las anteriores sino que se integran en un mix nuevo, único y actual, que corresponde a esta época en pleno despliegue. Por esto, en este contexto, algunas consideraciones para tener en cuenta a la horade hacer circular información en la prensa: 1) es un tiempo caracterizado por la sobreabundancia de información; 2) la atención está repartida en múltiples pantallas y dispositivos móviles; 3) la paradoja es el consumo racionado, en aquello que logre en pocos segundos captar la atención y contar una historia; 4) una historia que pueda sintetizarse en lo posible en una imagen, o en un formato audiovisual de impacto, que incluya material complementario en otros formatos digitales relacionados, integrados en una plataforma multimedia; y 5) se requieren habilidades y destrezas vinculadas con el diseño digital y las nuevas tecnologías, como la capacidad de interpretar y seguir las nuevas tendencias en contenidos en redes sociales.En este marco, los comunicadores encuentran un nuevo desafío: aprender a gestionar la comunicación y transmitir los mensajes clave a la prensa, en un modelo nuevo que presenta nuevas variables, con un contexto en el que permanece el cambio constante. Así, se introducen nuevos elementos que reformulan las prácticas y las herramientas utilizadas tradicionalmente en la gestión de relaciones con la prensa y medios de comunicación. En este trabajo se revisaron, recopilaron y presentaron estas nuevas modalidades y opciones de herramientas para difundir información con este público clave, por el alcance y visibilidad que proporciona a los mensajes de la empresa u organización