Now showing items 1-20 of 467

    • The satisfiability problem in regular CNF-formulas 

      Manyà Serres, Felip; Béjar Torres, Ramón; Escalada Imaz, G. (Springer Verlag, 1998)
      In this paper we deal with the propositional satisfiability (SAT) problem for a kind of multiple-valued clausal forms known as regular CNF-formulas and extend some known results from classical logic to this kind ...
    • A Time-Domain Method for the Analysis of Thermal Impedance Response Preserving the Convolution Form 

      Carmona, Manuel; Marco, Santiago; Palacín Roca, Jordi; Samitier, Josep (Institute of Electrical and Electronics Engineers, 1999)
      The study of the thermal behavior of complex packages as multichip modules (MCM’s) is usually carried out by measuring the so-called thermal impedance response, that is: the transient temperature after a power step. ...
    • Exploiting Knowledge of Temporal Behaviour in Parallel Programs for Improving Distributed Mapping 

      Roig Mateu, Concepció; Ripoll, A.; Senar, M.A.; Guirado Fernández, Fernando; Luque, Emilio (Springer Verlag, 2000)
      In the distributed processing area, mapping and scheduling are very important issues in order to exploit the gain from parallelization. The generation of efficient static mapping techniques implies a previous modelling ...
    • Monito: A Communication Monitoring Tool for a PVM-Linux Environment 

      Solsona Tehàs, Francesc; Giné, Francesc; Lérida Monsó, Josep Lluís; Hernandez, Porfidio; Luque, Emilio (Springer Verlag, 2000)
      In this paper a new tool for monitoring the different queues of messages in a PVM environment is presented. The main aim of implementing this facility is to provide a means of capturing the bottlenecks and overheads of ...
    • Implementing Explicit and Implicit Coscheduling in a PVM Environment 

      Solsona Tehàs, Francesc; Giné, Francesc; Hernandez, Porfidio; Luque, Emilio (Springer Verlag, 2000)
      Our efforts are directed towards the understanding of the coscheduling mechanism in a NOW system when a parallel job is executed with local workloads, balancing parallel efficiency against the local interactive response. ...
    • Coscheduling under Memory Constraints in a NOW 

      Giné, Francesc; Solsona Tehàs, Francesc; Hernández Budé, Porfidio; Luque, Emilio (Springer Verlag, 2001)
      Networks of Workstations (NOW) have become important and cost-effective parallel platforms for scientific computations. In practice, a NOW system is heterogeneous and non-dedicated. These two unique factors make scheduling ...
    • Improved Multiexponential Transcient Spectroscopy By Iterative Deconvolution 

      Marco, Santiago; Palacín Roca, Jordi; Samitier, Josep (Institute of Electrical and Electronics Engineers, 2001)
      The analysis of multiexponential decays is challenging because of their complex nature. When analyzing these signals, not only the parameters, but also the orders of the models, have to be estimated. Here, we present ...
    • Efficient Mapping for Message-Passing Applications Using the TTIG Model: A Case Study in Image Processing 

      Roig Mateu, Concepció; Ripoll, A.; Borrás, Javier; Luque, Emilio (Springer Verlag, 2001)
      In this paper we describe the development and performance of an image processing application with functional parallelism within the PVM framework. The temporal behaviour of the application is statically modelled with ...
    • Implementing and Analysing an Effective Explicit Coscheduling Algorithm on a NOW 

      Solsona Tehàs, Francesc; Giné, Francesc; Molina, Fermín; Hernandez, Porfidio; Luque, Emilio (Springer Verlag, 2001)
      Networks of workstations (NOWs) have become important and cost-effective parallel platforms for scientific computations. In practice, a NOW system is heterogeneous and non-dedicated. These two unique factors make ...
    • Predictive Coscheduling Implementation in a non-dedicated Linux Cluster 

      Solsona Tehàs, Francesc; Giné, Francesc; Hernandez, Porfidio; Luque, Emilio (Springer Verlag, 2001)
      Our research is focussed on keeping both local and parallel jobs together in a non-dedicated cluster or NOW (Network Of Workstations) and efficiently scheduling them by means of coscheduling mechanisms. A real implementation ...
    • Suboptimal Filtering and Nonlinear Time Scale Transformation for the Analysis of Multiexponential Decays 

      Palacín Roca, Jordi; Marco, Santiago; Samitier, Josep (IEEE, 2001)
      Multiexponential decays may contain time-constants differing in several orders of magnitudes. In such cases, uniform sampling results in very long records featuring a high degree of oversampling at the final part of the ...
    • MemTo: A Memory Monitoring Tool for a Linux Cluster 

      Giné, Francesc; Solsona Tehàs, Francesc; Navarro, Xavi; Hernandez, Porfidio; Luque, Emilio (Springer Verlag, 2001)
      Studies dealing with tuning, performance debugging and diagnosis in cluster environments largely benefit from in-depth knowledge of memory system information. In this paper a tool (called MemTo) for monitoring the ...
    • Immersion corrosion tests on metal-salt hydrate pairs used for latent heat storage in the 32 to 36 8C temperature range 

      Cabeza, Luisa F.; Illa i Alibés, Josep; Roca Enrich, Joan; Badia Pascual, Ferran; Mehling, Harald; Hiebler, Stefan; Ziegler, F. (Wiley, 2001)
      During the last decades, energy storage has become more and more important. It is required in order to utilize alternative energy sources, which often are available at times when energy is not needed. The main applications ...
    • Extending the Reach of SAT with Many-Valued Logics 

      Béjar Torres, Ramón; Cabiscol i Teixidó, Alba; Fernàndez Camon, César; Manyà Serres, Felip; Gomes, Carla (Elsevier, 2001)
      We present Regular-SAT, an extension of Boolean Satisfiability based on a class of many-valued CNFform ulas. Regular-SAT shares many properties with Boolean SAT, which allows us to generalize some of the best known SAT ...
    • Capturing Structure with Satisfiability 

      Béjar Torres, Ramón; Cabiscol i Teixidó, Alba; Fernàndez Camon, César; Manyà Serres, Felip; Gomes, Carla (Springer Verlag, 2001)
      We present Regular-SAT, an extension of Boolean Satisfiability basedon a class of many-valuedCNF formulas. Regular-SAT shares many properties with Boolean SAT, which allows us to generalize some of the best known SAT ...
    • A Fully Scalable and Distributed Architecture for Video-on-Demand 

      Cores Prado, Fernando; Ripoll, A.; Luque, Emilio (Springer Verlag, 2001)
      In spite of the attractiveness of Video-on-demand (VoD) services, their implantation to the present has not been as widespread as could have been desired due to centralized VoD systems have a limited streaming capacity ...
    • La resolución de problemas entre iguales: incidencia de la mediación del ordenador en los procesos de interacción y en el aprendizaje 

      Pifarré Turmo, Manoli; Sanuy Burgués, Jaume (Fundación Infancia y Aprendizaje, 2002)
      En el presente trabajo se analiza la incidencia de la mediación del ordenador en la resolución de problemas y en los procesos de interacción entre parejas de alumnos de la Enseñanza Secundaria Obligatoria. Para ello, se ...
    • Adjusting the Lengths of Time Slices when Scheduling PVM Jobs with High Memory Requirements 

      Giné, Francesc; Solsona Tehàs, Francesc; Hernandez, Porfidio; Luque, Emilio (Springer Verlag, 2002)
      Our research is focussed on keeping both local and parallel jobs together in a non-dedicated cluster and scheduling them efficiently. In such systems, the overflow of the physical memory into the virtual memory usually ...
    • 128 x 128 CMOS Image Sensor With Analog Memory for Synchronous Image Capture 

      Chapinal, Genis; Bota, Sebastian A.; Moreno, Mauricio; Palacín Roca, Jordi; Herms, Atilà (Institute of Electrical and Electronic Engineers, 2002)
      A 128 x 128 CMOS imager that permits synchronous capture is presented. The sensor combines the best of CMOS imagers (low-power, random readout, nondestructive readout, single supply voltage…) and synchronous capture ...
    • The Effects of Coronary Occlusion Location on the RR Signal 

      Clarià Sancho, Francisco; Vallverdú, Montserrat; Caminal Magrans, Pere (Institute of Electrical and Electronics Engineers, 2002)
      In this article, we carry out the study of the energy contribution of theRRsignal in the three frequency bands (LF, MF, and HF) during PTCA. Furthermore, variables based on instantaneous frequency and on group delay ...