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UPCommons, el portal d'accés obert al coneixement de la UPC, està format pel conjunt de dipòsits institucionals oberts de la UPC i té com a missió garantir la preservació de la producció docent i de recerca cientificotècnica de la Universitat, maximitzant-ne la visibilitat i, conseqüentment, incrementant-ne l’impacte en la docència i la recerca de tot el món.
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A content aware integer register file organization

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A content aware integer register file organization González García, Rubén; Cristal Kestelman, Adrián; Ortega Fernández, Daniel; Veidenbaum, Alex; Valero Cortés, Mateo A register file is a critical component of a modern superscalar processor. It has a large number of entries and read/write ports in order to enable high levels of instruction parallelism. As a result, the register file's area, access time, and energy consumption increase dramatically, significantly affecting the overall superscalar processor's performance and energy consumption. This is especially true in 64-bit processors. This paper presents a new integer register file organization, which reduces energy consumption, area, and access time of the register file with a minimal effect on overall IPC. This is accomplished by exploiting a new concept, partial value locality, which is defined as occurrence of multiple live value instances identical in a subset of their bits. A possible implementation of the new register file is described and shown to obtain proposed optimized register file designs. Overall, an energy reduction of over 50%, a 18% decrease in area, and a 15% reduction in the access time are achieved in the new register file. The energy and area savings are achieved with a 1.7% reduction in IPC for integer applications and a negligible 0.3% in numerical applications, assuming the same clock frequency. A performance increase of up to 13% is possible if the clock frequency can be increases due to a reduction in the register file access time. This approach enables other, very promising optimizations, three of which are outlined in the paper.
Categories: Novetats

On the scalability of 1- and 2-dimensional SIMD extensions for multimedia applications

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On the scalability of 1- and 2-dimensional SIMD extensions for multimedia applications Sánchez Castaño, Friman; Álvarez Mesa, Mauricio; Salamí San Juan, Esther; Ramírez Bellido, Alejandro; Valero Cortés, Mateo SIMD extensions are the most common technique used in current processors for multimedia computing. In order to obtain more performance for emerging applications SIMD extensions need to be scaled. In this paper we perform a scalability analysis of SIMD extensions for multimedia applications. Scaling a 1-dimensional extension, like Intel MMX, was compared to scaling a 2-dimensional (matrix) extension. Evaluations have demonstrated that the 2-d architecture is able to use more parallel hardware than the 1-d extension. Speed-ups over a 2-way superscalar processor with MMX-like extension go up to 4X for kernels and up to 3.3X for complete applications and the matrix architecture can deliver, in some cases, more performance with simpler processor configurations. The experiments also show that the scaled matrix architecture is reaching the limits of the DLP available in the internal loops of common multimedia kernels.
Categories: Novetats

CCT-2018-01-18-Presentación del cómic “La vampira de Barcelona” (audio y vídeo)

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CCT-2018-01-18-Presentación del cómic “La vampira de Barcelona” (audio y vídeo) Ojeda Rodríguez, Jordi Audio y vídeo de la presentación del cómic “La vampira de Barcelona” publicado por Norma Editorial con los autores Miguel Ángel Parra (guionista), Iván Ledesma (guionista) y Jandro González (dibujante). En la mesa de izquierda a derecha: Iván Ledesma, Jordi Ojeda (presentador), Miguel Ángel Parra y Jandro González.; 43 minutos en castellano. Jueves, 18 de enero de 2018 a las 19:00h en la Llibreria La Central del Raval.; Nota de prensa de Norma Editorial: EL CASO QUE ATERRORIZÓ A LA SOCIEDAD BARCELONESA DE COMIENZOS DEL SIGLO XX. “La vampira de Barcelona”, “la mala dona”, “la secuestradora de niños”… mendiga de día y gran señora de noche. Acusada de corrupción de menores, asesinato y curanderismo. ¿Realidad, ficción o exageración de la prensa del momento? En 1912, Enriqueta Martí fue detenida por el secuestro de Teresita Guitart y el supuesto asesinato de niños a los que prostituía y mataba para la preparación de ungüentos curativos destinados a la alta burguesía catalana.; Jandro González, Miguel Ángel Parra e Iván Ledesma, nos ofrecen en las páginas de esta novela gráfica una nueva interpretación del atroz suceso que aterrorizó a la sociedad barcelonesa de principios del siglo XX.; Más información en: http://comiccienciatecnologia.blogspot.com.es/
Categories: Novetats

Measurement of very low (alpha,n) cross sections of astrophysical interest

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Measurement of very low (alpha,n) cross sections of astrophysical interest Taín, J.L.; Jordán, D.; Agramunt Ros, Jorge; Caballero-Folch, R.; Calviño Tavares, Francisco; Cortés Rossell, Guillem Pere The reactions 13C(alpha, n)16O and 22Ne(alpha, n)25Mg are the primary sources of neutrons for the astrophysical s-process. The feasibility of cross section measurements within the respective Gamow windows is discussed in quantitative terms for a 4p neutron counter, based on 3He tubes and a neutron moderator, placed in an underground lab.
Categories: Novetats

A vector-µSIMD-VLIW architecture for multimedia applications

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A vector-µSIMD-VLIW architecture for multimedia applications Salamí San Juan, Esther; Valero Cortés, Mateo Media processing has motivated strong changes in the focus and design of processors. These applications are composed of heterogeneous regions of code, some of them with high levels of DLP and other ones with only modest amounts of ILP. A common approach to deal with these applications are /spl mu/SIMD-VLIWprocessors. However, the ILP regions fail to scale when we increase the width of the machine, which, on the other hand, is desired to achieve high performance in the DLP regions. In this paper, we propose and evaluate adding vector capabilities to a /spl mu/SIMD-VLIW core to speed-up the execution of the DLP regions, while, at the same time, reducing the fetch bandwidth requirements. Results show that, in the DLP regions, both 2 and 4-issue width vector-/spl mu/SIMD-VLIW architectures outperform a 8-issue width /spl mu/SIMD-VLIW in factors of up to 2.7X and 4.2X (1.6X and 2.1X in average) respectively. As a result, the DLP regions become less than 10% of the total execution time and performance is dominated by the ILP regions.
Categories: Novetats

Parallel processing in biological sequence comparison using general purpose processors

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Parallel processing in biological sequence comparison using general purpose processors Sánchez Castaño, Friman; Salamí San Juan, Esther; Ramírez Bellido, Alejandro; Valero Cortés, Mateo The comparison and alignment of DNA and protein sequences are important tasks in molecular biology and bioinformatics. One of the most well known algorithms to perform the string-matching operation present in these tasks is the Smith-Waterman algorithm (SW). However, it is a computation intensive algorithm, and many researchers have developed heuristic strategies to avoid using it, specially when using large databases to perform the search. There are several efficient implementations of the SW algorithm on general purpose processors. These implementations try to extract data-level parallelism taking advantage of single-instruction multiple-data extensions (SIMD), capable of performing several operations in parallel on a set of data. In this paper, we propose a more efficient data parallel implementation of the SW algorithm. Our proposed implementation obtains a 30% reduction in the execution time relative to the previous best data-parallel alternative. In this paper we review different alternative implementation of the SW algorithm, compare them with our proposal, and present preliminary results for some heuristic implementations. Finally, we present a detailed study of the computational complexity of the different alignment algorithms presented and their behavior on the different aspect of the CPU microarchitecture.
Categories: Novetats

Online prediction of applications cache utility

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Online prediction of applications cache utility Moreto Planas, Miquel; Cazorla, Francisco; Ramírez Bellido, Alejandro; Valero Cortés, Mateo General purpose architectures are designed to offer average high performance regardless of the particular application that is being run. Performance and power inefficiencies appear as a consequence for some programs. Reconfigurable hardware (cache hierarchy, branch predictor, execution units, bandwidth, etc.) has been proposed to overcome these inefficiencies by dynamically adapting the architecture to the application needs. However, nearly all the proposals use indirect measures or heuristics of performance to decide new configurations, what may lead to inefficiencies. In this paper we propose a runtime mechanism that allows to predict the throughput of an application on an architecture using a reconfigurable L2 cache. L2 cache size varies at a way granularity and we predict the performance of the same application on all other L2 cache sizes at the same time. We obtain for different L2 cache sizes an average error of 3.11%, a maximum error of 16.4% and standard deviation of 3.7%. No profiling or operating system participation is needed in this mechanism. We also give a hardware implementation that allows to reduce the hardware cost under 0.4% of the total L2 size and maintains high accuracy. This mechanism can be used to reduce power consumption in single threaded architectures and improve performance in multithreaded architectures that dynamically partition shared L2 caches.
Categories: Novetats

MLP-aware dynamic cache partitioning

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MLP-aware dynamic cache partitioning Moreto Planas, Miquel; Cazorla Almeida, Francisco Javier; Ramírez Bellido, Alejandro; Valero Cortés, Mateo The limitation imposed by instruction-level parallelism (ILP) has motivated the use of thread-level parallelism (TLP) as a common strategy for improving processor performance. TLP paradigms such as simultaneous multithreading (SMT), chip multiprocessing (CMP) and combinations of both offer the opportunity to obtain higher throughputs. However, they also have to face the challenge of sharing resources of the architecture. Simply avoiding any resource control can lead to undesired situations where one thread is monopolizing all the resources and harming the other threads. Some studies deal with the resource sharing problem in SMTs at core level resources like issue queues, registers, etc. In CMPs, resource sharing is lower than in SMT, focusing in the cache hierarchy.
Categories: Novetats

Tecnología de Contenedores Docker

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Tecnología de Contenedores Docker Ponsico Martin, Pol Docker is a project that allows you to create applications in software containers that are light, portable and self-sufficient Containers are a package of items that allow you to create an environment in which applications run independently of the operating system. The purpose of this project is to investigate the use of server virtualization based on Docker Containers, understand the technology running behind it, learn about the possibilities that it has and build a container cluster.; Docker es un proyecto que permite crear aplicaciones en contenedores de software que son ligeros, portátiles y autosuficientes El propósito de este proyecto es investigar el uso de la virtualización de servidores basada en Docker Containers, entender la tecnología que se ejecuta detrás de ella, conocer las posibilidades que tiene y construir un clúster de contenedores que ejecuten una aplicación.; Docker és un projecte que permet crear aplicacions en contenidors de programari que siguin lleugeres, portàtils i autosuficients Els contenidors són paquets d'elements que et permeten crear un entorn on córrer aplicacions independentment del sistema operatiu del host El propòsit d'aquest projecte és investigar l'ús de la virtualització de servidors basada en Docker Containers, entendre la tecnologia que s'executa darrere d'ella, conèixer les possibilitats que té i construir un clúster de contenidors que executin una aplicació.
Categories: Novetats

Runahead threads: reducing resource contention in SMT processors

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Runahead threads: reducing resource contention in SMT processors Ramírez García, Tanausu; Pajuelo González, Manuel Alejandro; Santana Jaria, Oliverio J.; Valero Cortés, Mateo In this work, we propose Runahead threads as a valuable solution for both exploiting memory-level parallelism and reducing resource contention in simultaneous multithreaded processors.
Categories: Novetats

Los pies sobre el agua: el rol del Acuífero Patiño en el equilibrio metabólico de Asunción y su Región Metropolitana

dv., 01/19/2018 - 19:58
Los pies sobre el agua: el rol del Acuífero Patiño en el equilibrio metabólico de Asunción y su Región Metropolitana Gill Robbiani, María Paz Màster universitari en Estudis Avançats en Arquitectura: Urbanisme
Categories: Novetats

Characteristics and dynamics of crescentic bar events in an open, tideless beach

dv., 01/19/2018 - 19:33
Characteristics and dynamics of crescentic bar events in an open, tideless beach De Swart, Rinse Leendert; Ribas Prats, Francesca; Ruessink, Gerben; Simarro, Gonzalo; Guillén Aranda, Jorge Crescentic bar events at Castelldefels beach (NW Mediterranean) have been characterised using a 4.25 years dataset (October 2010-December 2014) of time-exposure video images. Crescentic bars are observed during 41% of the study period, with an irregular distribution of the events in the different years. The crescentic bars have a lifetime that varies from 1 to over 100 days, a mean wavelength of 245 m and a mean amplitude of 9 m. The bars are observed in relatively low-energetic wave conditions with a wide variety of wave angles. The formation of crescentic bars also depends on the antecedent bathymetry, in particular crescentic bar events only occur when the sandbar is located at least at 50 m from the shoreline. Crescentic bar destruction at Castelldefels beach is observed in both low- and high energetic wave conditions, but the angle of incidence is always oblique.
Categories: Novetats

A data-driven approach to construct survey-based indicators by means of evolutionary algorithms

dv., 01/19/2018 - 19:05
A data-driven approach to construct survey-based indicators by means of evolutionary algorithms Claveria, Oscar; Monte Moreno, Enrique; Torra Porras, Salvador In this paper we propose a data-driven approach for the construction of survey-based indicators using large data sets. We make use of agents’ expectations about a wide range of economic variables contained in the World Economic Survey, which is a tendency survey conducted by the Ifo Institute for Economic Research. By means of genetic programming we estimate a symbolic regression that links survey-based expectations to a quantitative variable used as a yardstick, deriving mathematical functional forms that approximate the target variable. We use the evolution of GDP as a target. This set of empirically-generated indicators of economic growth, are used as building blocks to construct an economic indicator. We compare the proposed indicator to the Economic Climate Index, and we evaluate its predictive performance to track the evolution of the GDP in ten European economies. We find that in most countries the proposed indicator outperforms forecasts generated by a benchmark model. The final publication is available at Springer via http://dx.doi.org/10.1007/s11205-016-1490-3
Categories: Novetats

Formation and destruction events of shoreline sand waves

dv., 01/19/2018 - 18:22
Formation and destruction events of shoreline sand waves Arriaga García, Jaime Alonso; Falqués Serra, Albert; Ribas Prats, Francesca
Categories: Novetats

A distributed man-machine dispatching architecture for emergency operations based on 3GPP mission critical services

dv., 01/19/2018 - 16:57
A distributed man-machine dispatching architecture for emergency operations based on 3GPP mission critical services Viamonte Solé, David; Calveras Augé, Anna M. With the number of non-human devices expected to significantly overtake human users of LTE networks, it is no surprise that First Responders in Mission Critical operations will need to interact with an increasing number of unmanned devices, “bots” or drones. In the paper we propose the Mission Critical “bot” concept as an entity capable of gathering environmental/situational information and triggering certain automated actions without the need of human intervention. We prove that in certain circumstances these bots can help quickly resolve emergency situations and complement traditional centralized coordination from Dispatch Control Rooms. We explain how such “bots” relate and expand the 3GPP Mission Critical Communications architecture framework, considering different architectural approaches and complexity levels. Importantly, because First Responders must remain focused, hands-free and context-aware most of the time, we cover specifically the case where man-machine interaction is based on voice communication without having to use hands or look at a screen. It is hence of particular interest to convert “bot” interactions into audio information exchanged over push-to-talk communication services, be it through the cellular network or leveraging the 3GPP device-to-device capability. The paper is complemented with theoretical use cases as well as description and multimedia material of a prototype implementation of a concept emulator.
Categories: Novetats

STED imaging performance estimation by means of Fourier transform analysis

dv., 01/19/2018 - 16:34
STED imaging performance estimation by means of Fourier transform analysis Merino, David; Mallabiabarrena, Arrate; Andilla, Jordi; Artigas García, David; Zimmermann, Timo; Loza Alvarez, Pablo Due to relatively high powers used in STED, biological samples may be affected by the illumination in the process of image acquisition. Similarly, the performance of the system may be limited by the sample itself. Optimization of the STED parameters taking into account the sample itself is therefore a complex task as there is no clear methodology that can determine the image improvement in an objective and quantitative manner. In this work, a method based on Fourier transform formalism is presented to analyze the performance of a STED system. The spatial frequency distribution of pairs of confocal and STED images are compared to obtain an objective parameter, the Azimuth Averaged Spectral Content Spread (AASCS), that is related to the performance of the system in which the sample is also considered. The method has been first tested on samples of beads, and then applied to cell samples labeled with multiple fluorescent dyes. The results show that a single parameter, the AASCS, can be used to determine the optimal settings for STED image acquisition in an objective way, only by using the information provided by the images from the sample themselves. The AASCS also helps minimize the depletion power, for better preservation of the samples.
Categories: Novetats

Charles Baudelaire e la modernità parigina

dv., 01/19/2018 - 16:09
Charles Baudelaire e la modernità parigina Pizza de Nanno, Antonio
Categories: Novetats

Lengua y lenguaje arquitectónico como elemento de afirmación catalanista en el tiempo del modernisme

dv., 01/19/2018 - 15:36
Lengua y lenguaje arquitectónico como elemento de afirmación catalanista en el tiempo del modernisme Cardoso Barretto, Diogo; Ramon Graells, Antoni At the turn of the nineteenth and twentieth centuries, the issue of identity grew stronger in Catalonia. Of course, architecture was not immune to this trend. Meanwhile, issues of language as an element of identity gain importance both in Europe — with the idealistic defense of Johann Gottlieb Fichte — and in Catalonia — with Pompeu Fabra’s linguistic reform. In this article, we will analyze the relationship between language and architectural language in the context of redemption and reinterpretation of Catalan identity. We will focus on the analysis of the ideas of the architects Josep Puig i Cadafalch and Bonaventura Bassegoda i Amigó and their aspects related to the language of Romanesque and Catalan identity.
Categories: Novetats

Estudio cuantitativo de la calidad sonora de una guitarra española

dv., 01/19/2018 - 15:35
Estudio cuantitativo de la calidad sonora de una guitarra española Bustins Molina, Denis Este proyecto, tiene como objetivo principal hacer un estudio, mediante ensayos experimentales, de la calidad sonora de una guitarra española. El proyecto consta de dos partes, una descriptiva y otra experimental. En la primera parte explicaremos el objeto de estudio, que es la guitarra. Hablaremos de sus partes constitutivas, cómo afecta cada parte de la guitarra en la calidad sonora, haremos una breve explicación de su evolución histórica y estudiaremos su comportamiento dinámico. También daremos cuatro pinceladas sobre acústica, explicando cómo se comporta el sonido, qué propiedades lo caracteriza, qué fenómenos físicos intervienen en él y la aplicación directa de estos conocimientos a la guitarra. La segunda parte consiste en aplicar parte de esos conocimientos a ensayos experimentales, y comprobar si los resultados obtenidos coinciden con la teoría explicada en el primer apartado. En estos ensayos compararemos tres guitarras de tres niveles de calidad distintas, estimulándolas manualmente y grabando su sonido en una cámara semianecoica mediante diez micrófonos. Una vez captada la señal, la procesaremos mediante el programa Matlab y haremos un post-procesado manual para obtener los resultados que deseamos estudiar y comparar. Una vez obtenidos los resultados, haremos una comparación entre guitarras y analizaremos si los resultados logrados coinciden con los distintos niveles de calidad de cada guitarra.
Categories: Novetats

Assessment of RSS model calibration with real WLAN devices

dv., 01/19/2018 - 15:35
Assessment of RSS model calibration with real WLAN devices Castro, Juan Manuel; Moragrega, Ana; Closas, Pau; Fernández Rubio, Juan Antonio Received Signal Strength (RSS) for indoor localization is widely used due to its simplicity and availability in most mobile devices. The RSS channel model is defined by the propagation losses and the shadow fading. This paper studies two-slope RSS channel model and compares its validity to classical one-slope path loss model. Particularly, the work presents real-data results of a Bayesian calibration method. Validation of the model fitting is then performed in a dynamic scenario where the distance to a reference node is tracked by a Kalman Filter. Results show the superiority of two-slope model, specially at large distances.
Categories: Novetats

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