Modelling of a solar heat for industrial process (ship) system using fresnel collectors

The Solar Heat for Industrial Process (SHIP) systems has been pushed forward in recent years as an option to achieve the goal of decarbonizing the industrial sector. In this way, it is possible to partially cover the heat necessities from the industry with these systems and then save fuel consumption. Fresnel solar energy concentrators have proved to be a state-of-the-art technology to be implemented for heat generation in SHIP systems. In this work, a quasi-dynamic model for the simulation of operation and performance of a SHIP system with Fresnel collectors solar field and the dynamics and inertia of a kettle reboiler has been developed. The preliminary validation of the model has been performed using experimental data obtained from the SOLPINVAP experimental plant in Almazora, Spain.Thanks to the company SOLATOM CSP, for all the information and operatoinal data from the SHIP facility used in the present work. This work was partially supported by the Research and Development Aid Program (PAID-01-20) of the Universitat Politècnica de València for receiving the Research Fellowship FPI-UPV- 2020. This publication has been carried out in the framework of the project “DECARBONIZACIÓN DE EDIFICIOS E INDUSTRIAS CON SISTEMAS HÍBRIDOS DE BOMBA DE CALOR”, funded by the Spanish “Ministerio de Ciencia e Innovación (MCIIN)” with code number PID2020-115665RB-I00

Solving systems of symmetric Toeplitz tridiagonal equations: Rojo's algorithm revisited

More than 20 years ago, Rojo published [1] an algorithm for solving linear systems where the matrix is tridiagonal symmetric Toeplitz and diagonal dominant. The technique proposed by Rojo is very efficient, O(n), and has been applied successfully in the solution of other similar problems: circulant tridiagonal systems, pentadiagonal Toeplitz systems, etc. In this article we extend Rojo's algorithm to the case of non-diagonal dominant matrices, thus completing a good tool in the aforementioned applications. Other algorithms that solve the same problem are also analysed and compared with the new version of Rojo's algorithm. © 2012 Elsevier Inc. All rights reserved.Supported by Spanish Government (Projects TIN2008-06570-C04 and TEC2009-13741), and Generalitat Valenciana (Project PROMETEO/2009/013).Vidal Maciá, AM.; Alonso-Jordá, P. (2012). Solving systems of symmetric Toeplitz tridiagonal equations: Rojo's algorithm revisited. Applied Mathematics and Computation. 219(4):1874-1889. https://doi.org/10.1016/j.amc.2012.08.03018741889219

Efficient GPU Cloud architectures for outsourcing high-performance processing to the Cloud

The world is becoming increasingly dependant in computing intensive applications. The appearance of new paradigms, such as Internet of Things (IoT), and advances in technologies such as Computer Vision (CV) and Artificial Intelligence (AI) are creating a demand for high-performance applications. In this regard, Graphics Processing Units (GPUs) have the ability to provide better performance by allowing a high degree of data parallelism. These devices are also beneficial in specialized fields of manufacturing industry such as CAD/CAM. For all these applications, there is a recent tendency to offload these computations to the Cloud, using a computing offloading Cloud architecture. However, the use of GPUs in the Cloud presents some inefficiencies, where GPU virtualization is still not fully resolved, as our research on what main Cloud providers currently offer in terms of GPU Cloud instances shows. To address these problems, this paper first makes a review of current GPU technologies and programming techniques that increase concurrency, to then propose a Cloud computing outsourcing architecture to make more efficient use of these devices in the Cloud.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This work was supported by the Spanish Research Agency (AEI) under project HPC4Industry PID2020-120213RB-I00

Procedimientos y estrategias sostenibles. CAS 2020

La necesidad de repensar los espacios que habitamos es hoy indiscutible. El panorama actual nos ofrece un vasto abanico de desafíos en los que el entorno construido juega un papel principal. La arquitectura, ese escenario en el que transcurren nuestras vidas, implica un imprescindible ejercicio de responsabilidad. Diseñar lugares más amables con el medio ambiente y las personas es no solo consecuente con la vocación más inherente de la profesión sino una actitud fundamental ante una emergencia climática y sanitaria como esta, en la que la estrecha relación entre el bienestar y la salud se ha puesto más de manifiesto si cabe. Señala la Organización Mundial de la Salud que pasamos más del 90% del tiempo en el interior de edificios. Sirva este dato para reforzar la imperiosa oportunidad de reflexionar acerca de los espacios que generamos. El libro desarrolla esta temática a través de trabajos académicos de estudiantes de Arquitectura de la Universidad de Alicante

Improving the performance of water distribution systems’ simulation on multicore systems

The final publication is available at Springer via http://dx.doi.org/10.1007/s11227-015-1607-5Hydraulic solvers for the simulation of flows and pressures in water distribution systems (WDS) are used extensively, and their computational performance is key when considering optimization problems. This paper presents an approach to speedup the hydraulic solver using OpenMP with two efficient methods for WDS simulation. The paper identifies the different tasks carried out in the simulation, showing their contribution to the execution time, and selecting the target tasks for parallelization. After describing the algorithms for the selected tasks, parallel OpenMP versions are derived, with emphasis on the task of linear system update. Results are presented for four different large WDS models, showing considerable reduction in computing timeThis work has been partially supported by Ministerio de Economia y Competitividad from Spain, under the project TEC2012-38142-C04-01, and by project PROMETEO FASE II 2014/003 of Generalitat Valenciana.Alvarruiz Bermejo, F.; Martínez Alzamora, F.; Vidal Maciá, AM. (2016). Improving the performance of water distribution systems’ simulation on multicore systems. Journal of Supercomputing. 1-13. https://doi.org/10.1007/s11227-015-1607-5S113Abraham E, Stoianov I (2015) Efficient preconditioned iterative methods for hydraulic simulation of large scale water distribution networks. Proc Eng 119:623–632Abraham E, Stoianov I (2015) Sparse null space algorithms for hydraulic analysis of large-scale water supply networks. J Hydraul Eng. doi: 10.1061/(ASCE)HY.1943-7900.0001089Alonso JM, Alvarruiz F, Guerrero D et al (2000) Parallel computing in water network analysis and leakage minimization. J Water Resour Plan Manag 126(4):251–260Alvarruiz F, Martínez-Alzamora F, Vidal AM (2015) Efficient simulation of water distribution systems using openmp. In: 15th International conference computational and mathematical methods in computational mathematics, science and engineering, pp 125–129Alvarruiz F, Martínez-Alzamora F, Vidal AM (2015) Improving the efficiency of the loop method for the simulation of water distribution systems. J Water Resour Plan Manag 141(10):04015019Burger G, Sitzenfrei R, Kleidorfer M, Rauch W (2015) Quest for a new solver for EPANET 2. J Water Resour Plan Manag. doi: 10.1061/(ASCE)WR.1943-5452.0000596Creaco E, Franchini M (2014) Comparison of Newton–Raphson global and loop algorithms for water distribution network resolution. J Hydraul Eng 140(3):313–321Creaco E, Franchini M (2015) The identification of loops in water distribution networks. Proc Eng 119:506–515 Computing and Control for the Water Industry (CCWI2015) Sharing the best practice in water managementCrous PA, van Zyl JE, Roodt Y (2012) The potential of graphical processing units to solve hydraulic network equations. J Hydroinf 14:603–612Elhay S, Simpson A, Deuerlein J, Alexander B, Schilders W (2014) Reformulated co-tree flows method competitive with the global gradient algorithm for solving water distribution system equations. J Water Resour Plan Manag 140(12):04014040Epp R, Fowler AG (1970) Efficient code for steady-state flows in networks. J Hydraul Div 96(1):43–56Guidolin M, Burovskiy P, Kapelan Z, Savić D (2010) Cwsnet: an object-oriented toolkit for water distribution system simulations. In: Proceedings of 12th water distribution system analysis symposium, ASCE, Reston, VAGuidolin M, Kapelan Z, Savic D (2013) Using high performance techniques to accelerate demand-driven hydraulic solvers. J Hydroinf 15(1):38–54Guidolin M, Kapelan Z, Savic D, Giustolisi O (2010) High performance hydraulic simulations with epanet on graphics processing units. In: Proceedings of 9th international conference on hydroinformaticsOstfeld A, Uber J, Salomons E et al (2008) The battle of the water sensor networks (BWSN): a design challenge for engineers and algorithms. J Water Resour Plan Manag 134(6):556–568Rossman AL (2000) Epanet 2 users manual. Water Supply and Water Resources Division, US Environment Protection AgencyTodini E, Pilati S (1988) Computer applications in water supply: vol. 1—systems analysis and simulation. In: Coulbeck B, Orr CH (eds) A gradient algorithm for the analysis of pipe networks. Research Studies Press Ltd, Letchworth, Hertfordshire, UK, pp 1–2

Improving the efficiency of the loop method for the simulation of water distribution networks

Efficiency of hydraulic solvers for the simulation of flows and pressures in water distribution systems (WDSs) is very important, especially in the context of optimization and risk analysis problems, where the hydraulic simulation has to be repeated many times. Among the methods used for hydraulic solvers, the most prominent nowadays is the global gradient algorithm (GGA), based on a hybrid node-loop formulation. Previously, another method based just on loop flow equations was proposed, which presents the advantage that it leads to a system matrix that is in most cases much smaller than in the GGA method, but has also some disadvantages, mainly a less sparse system matrix and the fact that introducing some types of valves requires the redefinition of the set of network loops initially defined. The contribution of this paper is to present solutions for overcoming the mentioned disadvantages of the method based on loop flow equations. In particular, efficient procedures are shown for selecting the network loops so as to achieve a highly sparse matrix and methods are presented to incorporate check valves and automatic control valves while avoiding the need to redefine the loops initially selected. (C) 2015 American Society of Civil Engineers.This work has been partially supported by "Ministerio de Economia y Competitividad" from Spain, under the project TEC2012-38142-C04-01 and by PROMETEO FASE II 2014/003 project of Generalitat Valenciana.Alvarruiz Bermejo, F.; Martínez Alzamora, F.; Vidal Maciá, AM. (2015). Improving the efficiency of the loop method for the simulation of water distribution networks. Journal of Water Resources Planning and Management. 141(10):1-10. https://doi.org/10.1061/(ASCE)WR.1943-5452.0000539S1101411

Multichannel massive audio processing for a generalized crosstalk cancellation and equalization application using GPUs

[EN] Multichannel acoustic signal processing has undergone major development in recent years due to the increased com- plexity of current audio processing applications, which involves the processing of multiple sources, channels, or filters. A gen- eral scenario that appears in this context is the immersive reproduction of binaural audio without the use of headphones, which requires the use of a crosstalk canceler. However, generalized crosstalk cancellation and equalization (GCCE) requires high com- puting capacity, which is a considerable limitation for real-time applications. This paper discusses the design and implementation of all the processing blocks of a multichannel convolution on a GPU for real-time applications. To this end, a very efficient fil- tering method using specific data structures is proposed, which takes advantage of overlap-save filtering and filter fragmentation. It has been shown that, for a real-time application with 22 inputs and 64 outputs, the system is capable of managing 1408 filters of 2048 coefficients with a latency time less than 6 ms. The proposed GPU implementation can be easily adapted to any acoustic environment, demonstrating the validity of these co-processors for managing intensive multichannel audio applications.This work has been partially funded by Spanish Ministerio de Ciencia e Innovacion TEC2009-13741, Generalitat Valenciana PROMETEO 2009/2013 and GV/2010/027, and Universitat Politecnica de Valencia through Programa de Apoyo a la Investigacion y Desarrollo (PAID-05-11).Belloch Rodríguez, JA.; Gonzalez, A.; Martínez Zaldívar, FJ.; Vidal Maciá, AM. (2013). Multichannel massive audio processing for a generalized crosstalk cancellation and equalization application using GPUs. Integrated Computer-Aided Engineering. 20(2):169-182. https://doi.org/10.3233/ICA-130422S16918220

Efficient Modeling of Active Control Valves in Water Distribution Systems Using the Loop Method

[EN] This paper presents a novel approach to model pressure- and flow-regulating devices in the context of the Newton-Raphson loop method for water distribution network simulation. The proposed approach uses a symmetric matrix for the underlying linear systems, which enables simpler implementation and faster solution, while producing iterations very close to the global gradient algorithm of EPANET. The structure of the matrix is kept unchanged regardless of the operational status of the valves. The paper presents results that validate its formulation, accuracy, and speed in various case studies.Alvarruiz Bermejo, F.; Martínez Alzamora, F.; Vidal Maciá, AM. (2018). Efficient Modeling of Active Control Valves in Water Distribution Systems Using the Loop Method. Journal of Water Resources Planning and Management. 144(10):1-9. https://doi.org/10.1061/(ASCE)WR.1943-5452.0000982S191441

Block pivoting implementation of a symmetric Toeplitz solver

Toeplitz matrices are characterized by a special structure that can be exploited in order to obtain fast linear system solvers. These solvers are difficult to parallelize due to their low computational cost and their closely coupled data operations. We propose to transform the Toeplitz system matrix into a Cauchy-like matrix since the latter can be divided into two independent matrices of half the size of the system matrix and each one of these smaller arising matrices can be factorized efficiently in multicore computers. We use OpenMP and store data in memory by blocks in consecutive positions yielding a simple and efficient algorithm. In addition, by exploiting the fact that diagonal pivoting does not destroy the special structure of Cauchy-like matrices, we introduce a local diagonal pivoting technique which improves the accuracy of the solution and the stability of the algorithm.This work was partially supported by the Spanish Ministerio de Ciencia e Innovacion (Project TIN2008-06570-C04-02 and TEC2009-13741), Vicerrectorado de Investigacion de la Universidad Politecnica de Valencia through PAID-05-10 (ref. 2705), and Generalitat Valenciana through project PROMETEO/2009/2013.Alonso-Jordá, P.; Dolz Zaragozá, MF.; Vidal Maciá, AM. (2014). Block pivoting implementation of a symmetric Toeplitz solver. Journal of Parallel and Distributed Computing. 74(5):2392-2399. https://doi.org/10.1016/j.jpdc.2014.02.003S2392239974

Optimising Convolutions for Deep Learning Inference on ARM Cortex-M Processors

We perform a series of optimisations on the convo lution operator within the ARM CMSIS-NN library to improve the performance of deep learning tasks on Arduino development boards equipped with ARM Cortex-M4 and M7 microcontrollers. To this end, we develop custom microkernels that efficiently handle the internal computations required by the convolution operator via the lowering approach and the direct method, and we design two techniques to avoid register spilling. We also take advantage of all the RAM on the Arduino boards by reusing it as a scratchpad for the convolution filters. The integration of these techniques into CMSIS-NN, when invoked by TensorFlow Lite for microcontrollers for quantised versions of VGG, SqueezeNet, ResNet, and MobileNet-like convolutional neural networks enhances the overall inference speed by a factor ranging from 1.13× to 1.50×.This research was funded by project TED2021-129334B-I00 supported by MCIN/AEI/10.13039/501100011033 and by the “European Union NextGenerationEU/PRTR”. Manuel F. Dolz was also supported by the Plan Gen–T grant CIDEXG/2022/13 of the Generalitat Valenciana. Antonio Macia-Lillo is a PRE2021-099284 fellow supported by MCIN/AEI/10.13039/501100011033