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Title: Systematic energy characterization of CMP/SMT processor systems via automated micro-benchmarks
Authors: Bertrán, Ramon; Buyuktosunoglu, Alper; Gupta, Meeta S.; González Tallada, Marc; Bose, Pradip
Abstract: Microprocessor-based systems today are composed of multi-core, multi-threaded processors with complex cache hierarchies and gigabytes of main memory. Accurate characterization of such a system, through predictive pre-silicon modeling and/or diagnostic postsilicon measurement based analysis are increasingly cumbersome and error prone. This is especially true of energy-related characterization studies. In this paper, we take the position that automated micro-benchmarks generated with particular objectives in mind hold the key to obtaining accurate energy-related characterization. As such, we first present a flexible micro-benchmark generation framework (MicroProbe) that is used to probe complex multi-core/multi-threaded systems with a variety and range of energy-related queries in mind. We then present experimental results centered around an
IBM POWER7 CMP/SMT system to demonstrate how the systematically generated micro-benchmarks can be used to answer three
specific queries: (a) How to project application-specific (and if needed, phase-specific) power consumption with component-wise breakdowns? (b) How to measure energy-per-instruction (EPI) values for the target machine? (c) How to bound the worst-case (maximum) power consumption in order to determine safe, but practical (i.e. affordable) packaging or cooling solutions? The solution approaches to the above problems are all new. Hardware measurement
based analysis shows superior power projection accuracy (with error margins of less than 2.3% across SPEC CPU2006) as well as max-power stressing capability (with 10.7% increase in processor power over the very worst-case power seen during the execution of SPEC CPU2006 applications).
Title: Progressive emergence of double porosity in a silt during compaction
Authors: Casini, Francesca; Vaunat, Jean; Romero Morales, Enrique Edgar; Desideri, Augusto
Abstract: The paper deals with an experimental investigation of water retention properties of a statically compacted unsaturated low plasticity silt. The objective is a deeper understanding of the evolution of an aggregate type fabric at different initial conditions in terms of void ratio and water
content. A series of Mercury Intrusion Porosimetry tests (MIP) were performed to provide information about factors influencing fabric changes (effect of mechanical stress due to sample compaction)
and fabric-properties relationships (water retention curve related to porosimetry). The arrangements of aggregation/particles are also investigated with Environmental Scanning Electron Microscopy (ESEM). The experimental data has been used to calibrate a multimodal water retention model for aggregate which is obtained by linear superposition of sub-curves of the van Genuchten type modified. By comparing the WRC obtained by MIP and under suction controlled conditions it has been found a good agreement between the two method for the drying path.
Title: Laboratory experiments on swelling due to crystal growth in sulphate argillaceous rocks
Authors: Deu, Amadeu; Romero Morales, Enrique Edgar; Berdugo de Moya, Iván Rafael
Abstract: Crystal growth is a frequent cause of expansive deformations in natural soils, compacted soils, rocks and concrete. The sulphate crystallization in discontinuities and cracks due to evaporation of highly mineralized solutions can contribute in an important way to displacements and swelling pressures that usually appear in tunnels and deep foundations in argillaceous rocks. The present work is aimed to study the basic mechanisms that control the hydrated sulphate mineral growth in anhydritic-gypsiferous argillaceous rocks due to the evaporation of groundwater. The paper presents some laboratory works including
mineralogical and micro-structural analysis, as well as the design and development of new free swelling tests which were developed focusing on the capacity to discern the role carried out by the geochemical properties of the water, the main environmental variables and the degree of cracking on undisturbed sulphate argillaceous samples from different zones of the Lower Ebro Basin (Catalonia, Spain).
Title: Effects of relative humidity cycling on the hydro-mechanical behaviour of two clayey rocks from North-East Spain
Authors: Pineda Jiménez, Jubert Andrés; Alonso Pérez de Agreda, Eduardo
Abstract: The paper describes the results of an experimental research aimed at studying the effects of relative humidity cycling on the degradation phenomena of two clayey rocks from North-East Spain, with particular emphasis on peak shear strength, low-strain stiffness and water permeability. Undisturbed
samples were subjected to an extreme relative humidity cycle (between 15% and 99%) using the vapour transfer technique, before performing triaxial compression and water permeability tests. Rock stiffness
was evaluated by ultrasonic pulse tests. Test results showed clear differences in stiffness and shear strength response between undisturbed and degraded samples, highlighting the relevance of hydraulically induced degradation phenomena on this type of materials.
Title: A parallel algorithm for the computation of invariant tori in large-scale dissipative systems
Authors: Sánchez Umbría, Juan; Net Marcé, Marta
Abstract: A parallelizable algorithm to compute invariant tori of high-dimensional dissipative systems, obtained upon discretization of PDEs is presented. The size of the set of equations to be solved is only a small multiple of the dimension of the original system. The sequential and parallel implementations are compared with a previous method (Sánchez et al. (2010)) , showing that important savings in wall-clock time can be achieved. In order to test it, a thermal convection problem of a binary mixture of fluids has been used. The new method can also be applied to problems with very low rotation numbers, for which the previous is not suitable. This is tested in two examples of two-dimensional maps.
Title: Size effects on water adsorbed on hydrophobic probes at the nanometric scale
Authors: Calero Borrallo, Carles; Gordillo, Carmen; Martí Rabassa, Jordi
Abstract: Molecular dynamics simulations of liquid water at ambient conditions, adsorbed at the external walls of (n,n) single-walled armchair carbon nanotubes have been performed for n = 5, 9, 12. The comparison with the case of water adsorbed on graphene has also been included. The analysis of Helmholtz free energies reveals qualitatively different ranges of thermodynamical stability, eventually starting at a given threshold surface density. We observed that, in the framework of the force field considered here, water does not wet graphene nor (12,12) tubes, but it can coat thinner tubes such as (9,9) and (5,5), which indicates that the width of the carbon nanotube plays a role on wetting. On the other hand, density profiles, orientational distributions of water, and hydrogen-bond populations indicate significant changes of structure of water for the different surfaces. Further, we computed self-diffusion of water and spectral densities of water and carbon molecules, which again revealed different qualitative behavior of interfacial water depending on the size of the nanotube. The crossover size corresponds to tube diameters of around 1 nm.
Title: A bit more on the ability of adaptation of speech signals
Authors: Ballesteros, Dora Maria; Moreno Aróstegui, Juan Manuel
Abstract: Some traditional digital signal processing techniques encompass enhancement, filtering, coding, compression, detection and recognition. Recently, it has been presented a new hypothesis of signal processing known as the ability of adaptation of speech signals: an original speech signal may sound similar to a target speech signal if a relocation process of its wavelet coefficients is applied. This hypothesis is true under some conditions theoretically defined. In this paper we present the basic idea behind the hypothesis of adaptation and moreover, we test the hypothesis within four cases: speech signals with the same gender and language, speech signals with the same gender but different language, speech signals with the same language but different gender, and speech signals with different gender and language. It is found that the hypothesis is true if the requirements are satis® ed, even if the gender or the language of the original and target signals are not the same.
Title: Influence of hydrogen on the optical absorption response of GaAs(Ti) films deposited by R.F. sputtering
Authors: Boronat Moreiro, Alfredo; Silvestre Bergés, Santiago; Castañer Muñoz, Luis María
Abstract: In the present work we have investigated the optical absorption behavior of GaAs(Ti) films deposited by r.f sputtering technique under different H2 partial pressures. In previous work we have already demonstrated the feasibility to obtain GaAs films with high dose of Ti, which we refer to as GaAs(Ti). Any absorption peak, which could be related with the presence of an intermediate band, has been identified. The low Etauc parameter together with a broad Urbach tail of the films make us to suspect that the possible presence of an absorption peak could be hidden. The incorporation of H2 on sputtered GaAs films have demonstrated before a shift of the Etauc parameter to higher values and a reduction of the Urbach tail.
Title: Estudi sociodemogràfic i urbanístic de la Mariola
Authors: Gutiérrez Valdivia, Blanca Alexandra
Title: Treball de camp a la Mariola
Authors: Gutiérrez Valdivia, Blanca Alexandra
Title: Anàlisis geogràfic de espais i equipaments de Lleida
Authors: Gutiérrez Valdivia, Blanca Alexandra
Title: Sulfonic acid-functionalized aerogels as high resistant to deactivation catalysts for the etherification of glycerol with isobutene
Authors: González, Maria Dolores; Salagre, Pilar; Taboada Cabellos, Elena; Llorca Piqué, Jordi; Molins, E.; Cesteros, Yolanda
Abstract: Silica aerogel and lyogel have been successfully sulfonated in one step by a simple post-synthesis method using microwaves as well as conventional heating. The use of microwaves allowed loading higher amounts of sulfonic acid groups in both silicas, according to the higher S/Si atomic ratio determined by XPS, and the higher sulfur content determined by TGA, also exhibiting lower surface area and higher acidity. Sulfonated aerogels showed higher conversion and selectivity to h-GTBE (glycerol di- and tri-ethers) than sulfonated lyogels for the acid-catalyzed etherification of glycerol with isobutene. This was attributed to the higher content of sulfonic acid groups incorporated in aerogel. Microwave-assisted sulfonated aerogel yielded 75% of selectivity to h-GTBE, which can be used as fuel additive, for practically total conversion. Interestingly, larger porosity of aerogel avoided the partial blocking of pores by reaction products observed when other micro- and mesoporous catalysts were tested for this reaction. The combination of high conversion, high selectivity to h-GTBE, practically no formation of undesired di-isobutylenes and very high resistance to catalyst deactivation makes microwave-assisted sulfonic acid functionalized aerogel a promising catalyst for this etherification reaction.
Title: PdCu alloy nanoparticles on alumina as selective catalysts for trichloroethylene hydrodechlorination to ethylene
Authors: Meshesha, B.T.; Barrabes, Noelia; Llorca Piqué, Jordi; Dafinov, Antonio; Medina, Francisco; Foettinger, Karin
Abstract: PdCu bimetallic catalysts supported on alumina were prepared by different common impregnation protocols and by a polyol nanoparticles synthesis route. These materials were studied in order to establish the relationship between structure, particle size, Pd–Cu interaction and catalytic activity/selectivity in the hydrodechlorination of trichloroethylene (TCE) in gas phase. The surface properties and the interaction between Cu and Pd in the bimetallic particles, as well as their catalytic behaviour are strongly influenced by the preparation protocol. Depending on the synthesis, PdCu alloy formation or isolated phases were observed. The presence of isolated Pd particles leads to high ethane selectivity, whereas upon alloy formation or strong interaction between Pd and Cu a higher ethylene yield was obtained. By the nanoparticles polyol synthesis, Pd-Cu alloy formation was obtained, leading to total selectivity to ethylene in the TCE hydrodechlorination reaction. On the Pd monometallic catalysts larger particle size resulted in higher levels of ethylene formation.
Title: Work in progress - Cooperative and competitive projects for engaging students in advanced ICT subjects
Authors: Pardàs Feliu, Montse; Bonafonte Cávez, Antonio
Abstract: In this paper we present a specific kind of projects that can be used for project-based learning in engineering subjects. The subjects must combine lectures with projects, in order to provide the technical competences together with additional skills such as teamwork learning, oral and written communication skills and application of theory to practice. The projects proposed consist on improving an elemental baseline system. The system is decomposed in modules that correspond to the topics that have been learnt during the lectures. For improving the system, the class is divided in groups and each group has to propose, implement, assess and report a better system. In order to be able to improve the system with a limited amount of time and effort the students need to make a coherent proposal and split the project in several tasks that are usually developed by one or two students. The students within a group cooperate to achieve a better system, but groups compete for the best results. We have already implemented this kind of project in a Speech Processing course and we plan to apply it in a Video Coding course.
Title: Preliminary performance study of different radio-frequency interference detection and mitigation algorithms in microwave radiometry
Authors: Depau, Veronica; Tarongí Bauzá, José Miguel; Forte Veliz, Giuseppe; Camps Carmona, Adriano José
Abstract: This work presents the preliminary performance study of several RFI detection and mitigation algorithms applied to real data. The used algorithms include statistical analysis in the time and frequency domains and time and frequency domains analysis. The data has been acquired in an urban area using a new experimental radiometer called MERITXELL.
Title: CAPEX study for grid dependent multi-layer IP/MPLS-over-EON using relative BV-WSS costs
Authors: Pedrola Escribà, Òscar; Velasco Esteban, Luis Domingo; Fernández-Palacios, Juan Pedro; Castro Casales, Alberto; Careglio, Davide; Junyent Giralt, Gabriel
Abstract: The impact of the frequency grid on the CAPEX required to deploy a multi-layer IP/MPLS-over-EON is analyzed. Results showing significant savings at the electronic layer motivate the introduction of narrower grids with enhanced BV-WSS.
Authors: Barceló García, Miquel
Abstract: Tot i l'habitual creixement en potència i
nuclis dels microprocessadors, l'any va tenir
com a gran novetat l'estabilització del nou mercat dels telèfons intel·ligents (smartphones) i, sobre tot, de les "tauletes" (tablets), on diversos fabricants van començar a fer competència als iPhone i
iPad d'Apple que ja van comercialitzar noves
versions durant l'any 2011. També cal destacar que va crèixer de la idea de la "inf
ormàtica verda" (green computing) respectuosa amb el medi ambient i, sobre tot, la força de les xarxes socials quasi ja del tot imprescindibles. Sense oblidar la desaparició, en poques setmanes, de tres personatges que han estat fonamentals en diversos aspectes de la informàtica moderna, ni els esforços d'Europa per estar al dia en el tema dels projectes de futur de les TIC.
També és novetat l’arribada d’Amazon a Espanya, a partir de setembre d’enguany. Això
suposa, entre d’altres coses, una empenta
a la venda del seu lector de eBooks Kindle
que es proposa com a regal nadalenc.
Title: A hybrid cooperative design for energy-efficient surveillance in wireless multimedia sensor networks
Authors: Alaei, Mohammad; Barceló Ordinas, José María
Abstract: In Wireless Multimedia Sensor Networks (WMSNs) the lifetime of battery-operated visual nodes is limited by their energy consumption, which is proportional to the energy required for sensing, processing, and transmitting the data. Given the large amount of data generated by the visual nodes,
both processing and transmitting image data are quite costly in terms of energy in comparison with other types of sensor networks. Therefore, energy efficiency is a main concern in WMSNs. In this paper an energy efficient collaborative mechanism for environment surveillance is proposed. The
proposed scheme employs a mixed random deployment of acoustic and visual sensor nodes. Acoustic sensors detect and localize the occurred event/object(s) in a duty-cycled manner by sampling the received signals and then trigger the visual sensor
nodes covering the objects to monitor them. Hence, visual sensors are warily scheduled to be awakened just for monitoring the object(s) detected in their domain, otherwise they save their energy.
Title: Feature selection for the prediction and visualization of brain tumor types using proton magnetic resonance spectroscopy data
Authors: González Navarro, Félix Fernando; Belanche Muñoz, Luis Antonio
Abstract: In cancer diagnosis, classification of the different tumor types is of great importance. An accurate prediction of basic tumor types provides better treatment and may minimize the negative impact of incorrectly targeted toxic or aggressive treatments. Moreover, the correct prediction of cancer types in the brain using non-invasive information –e.g. 1H-MRS data– could avoid patients to suffer collateral problems derived from exploration techniques that require surgery. We present a feature selection algorithm that is specially designed to be used in 1H-MRS (Proton Magnetic Resonance Spectroscopy) data of brain tumors. This algorithm takes advantage of the fact that some metabolic levels may consistently present notorious differences between specific tumor types. We present detailed experimental results using an international dataset in which highly attractive models are obtained. The models are evaluated according to their accuracy, simplicity and medical interpretability. We also explore the influence of redundancy in the modelling process. Our results suggest that a moderate amount of redundant metabolites can actually enhance class-separability and therefore accuracy.
Title: Power control of VSC HVDC converters for limiting the influence of ac unbalanced faults on multi-terminal DC grids
Authors: Suul, Jon Are; Luna Alloza, Álvaro; Rodríguez Cortés, Pedro
Abstract: It will be important for the operation of future multi-terminal HVDC systems that each converter unit is capable of limiting the influence of nearby AC faults on the DC grid. Thus, the local control systems at each terminal should be able to prevent double frequency active power oscillations caused by unbalanced AC faults from propagating to the DC-side of the converter. A simple approach for achieving this objective, while ensuring that the converter currents are limited to safe values, is therefore presented in this paper. The proposed method is based on estimation of Positive and Negative Sequence Virtual Flux components at the terminals of the converter. Double frequency oscillations in the active power flow through the converter can...