Multicore Early Design Stage Guaranteed Performance Estimates for the Space Domain

The ability to produce early guaranteed performance (worst-case execution time) estimates for multicores, i.e. before software from different providers gets integrated onto the same critical system, is pivotal. This helps reducing lately-detected costly-to-handle timing violations. An existing methodology creates ‘copy’ (surrogate) applications from the execution in isolation of each target application. Surrogate applications can be used to upperbound multicore contention delay, and hence WCET estimates in multicores. However, this methodology has only been shown to work on a simulation environment. In this paper we show the work we have carried out to adapt this technology to a real multicore processor for the space domain.This work has been partially supported by the Spanish Ministry of Economy and Competitiveness (MINECO) under grant TIN2015-65316-P, and the HiPEAC Network of Excellence. Jaume Abella has been partially supported by the MINECO under Ramon y Cajal postdoc fellowship RYC-2013-14717.Peer ReviewedPostprint (author's final draft

Proyecto de mejora del proceso de ensayo aerodinámico en vehículos industriales conforme al R(UE) 2017/2400

La principal motivación de este proyecto es la necesidad de un Trabajo de Fin de Máster para dar por finalizados los estudios del Máster Universitario en Automoción. Este proyecto se ha llevado a cabo en la empresa IDIADA Automotive Technology, concretamente en el departamento de Performance & Driveability y durante unas prácticas trabajando en ensayos aerodinámicos en vehículos industriales. El origen del proyecto es la necesidad de mejoras en el procedimiento de ensayo aerodinámico definido en el Anexo VIII del Reglamento de la Comisión Europea 2017/2400, cuyo objetivo es la definición de la resistencia aerodinámica de vehículos industriales de cara al cálculo de los consumos de combustible y de las emisiones de CO2. El objetivo del proyecto ha sido el desarrollo y el análisis de factibilidad de dos sistemas, para optimizar los tiempos y el coste del procedimiento de ensayo. En primer lugar, y para dar contexto al proyecto, se expondrá el procedimiento de ensayo con sus fases (enfatizando especialmente en las fases en las que se aplicarán las mejoras) y los cálculos para la definición de la resistencia aerodinámica. También se especificarán los criterios de aceptación para la validez del ensayo. El primero de los proyectos de mejora se tratará de un elevador neumático, cuyo objetivo será el de elevar un anemómetro móvil instalado en la cara frontal del remolque o caja del vehículo industrial. Este proyecto asistirá a la elevación de este anemómetro, que actualmente se hace a mano, ahorrando tiempo y facilitando su movimiento en casos en los que se requiera su manipulación. Este sistema estará accionado por el sistema neumático de frenos del vehículo. El segundo proyecto de mejora es el de un sistema de elevación del eje tractor del vehículo de cara a una puesta a cero de los sensores de par instrumentados en el vehículo. La base de este sistema será un cilindro hidráulico accionado por la presión neumática del sistema de frenos del vehículo. Para este sistema, se diseñará tanto el apartado mecánico como su aplicación al procedimiento de ensayo, definiendo el nuevo procedimiento de elevación del eje tractor en la fase de puesta a cero de los sensores de par. Finalmente, se considerarán tanto las inversiones ambos proyectos de mejorase llevará a cabo el cálculo del ahorro que estos van a suponer para el precio de un ensayo. Con estos datos, se calculará la amortización de estas inversiones y se valorará si su aplicación real en el procedimiento sería conveniente

Tracing Hardware Monitors in the GR712RC Multicore Platform: Challenges and Lessons Learnt from a Space Case Study

The demand for increased computing performance is driving industry in critical-embedded systems (CES) domains, e.g. space, towards the use of multicores processors. Multicores, however, pose several challenges that must be addressed before their safe adoption in critical embedded domains. One of the prominent challenges is software timing analysis, a fundamental step in the verification and validation process. Monitoring and profiling solutions, traditionally used for debugging and optimization, are increasingly exploited for software timing in multicores. In particular, hardware event monitors related to requests to shared hardware resources are building block to assess and restraining multicore interference. Modern timing analysis techniques build on event monitors to track and control the contention tasks can generate each other in a multicore platform. In this paper we look into the hardware profiling problem from an industrial perspective and address both methodological and practical problems when monitoring a multicore application. We assess pros and cons of several profiling and tracing solutions, showing that several aspects need to be taken into account while considering the appropriate mechanism to collect and extract the profiling information from a multicore COTS platform. We address the profiling problem on a representative COTS platform for the aerospace domain to find that the availability of directly-accessible hardware counters is not a given, and it may be necessary to the develop specific tools that capture the needs of both the user’s and the timing analysis technique requirements. We report challenges in developing an event monitor tracing tool that works for bare-metal and RTEMS configurations and show the accuracy of the developed tool-set in profiling a real aerospace application. We also show how the profiling tools can be exploited, together with handcrafted benchmarks, to characterize the application behavior in terms of multicore timing interference.This work has been partially supported by a collaboration agreement between Thales Research and the Barcelona Supercomputing Center, and the European Research Council (ERC) under the EU’s Horizon 2020 research and innovation programme (grant agreement No. 772773). MINECO partially supported Jaume Abella under Ramon y Cajal postdoctoral fellowship (RYC2013-14717).Peer ReviewedPostprint (published version

EPC Enacted: Integration in an Industrial Toolbox and Use against a Railway Application

Measurement-based timing analysis approaches are increasingly making their way into several industrial domains on account of their good cost-benefit ratio. The trustworthiness of those methods, however, suffers from the limitation that their results are only valid for the particular paths and execution conditions that the user is able to explore with the available input vectors. It is generally not possible to guarantee that the collected measurements are fully representative of the worst-case timing behaviour. In the context of measurement-based probabilistic timing analysis, the Extended Path Coverage (EPC) approach has been recently proposed as a means to extend the representativeness of measurement observations, to obtain the same effect of full path coverage. At the time of its first publication, EPC had not reached an implementation maturity that could be trialled industrially. In this work we analyze the practical implications of using EPC with real-world applications, and discuss the challenges in integrating it in an industrial-quality toolchain. We show that we were able to meet EPC requirements and successfully evaluate the technique on a real Railway application, on top of a commercial toolchain and full execution stack.This work has received funding from the European Community’s Seventh Framework Programme [FP7/2007-2013] under grant agreement 611085 (PROXIMA, www.proxima-project.eu). This work has also been partially supported by the Spanish Ministry of Economy and Competitiveness (MINECO) under grant TIN2015-65316-P and the HiPEAC Network of Excellence. Jaume Abella has been partially supported by the MINECO under Ramon y Cajal postdoctoral fellowship number RYC-2013-14717. The authors are grateful to Antoine Colin from Rapita Ltd. for his precious support.Peer ReviewedPostprint (author's final draft

Probabilistic timing analysis on time-randomized platforms for the space domain

Timing Verification is a fundamental step in real-time embedded systems, with measurement-based timing analysis (MBTA) being the most common approach used to that end. We present a Space case study on a real platform that has been modified to support a probabilistic variant of MBTA called MBPTA. Our platform provides the properties required by MBPTA with the predicted WCET estimates with MBPTA being competitive to those with current MBTA practice while providing more solid evidence on their correctness for certification.The research leading to these results has received funding from the European Community’s FP7 [FP7/2007-2013] under the PROXIMA Project (www.proxima-project.eu), grant agreement no 611085. This work has also been partially supported by the Spanish Ministry of Science and Innovation under grant TIN2015-65316-P and the HiPEAC Network of Excellence. Jaume Abella has been partially supported by the Ministry of Economy and Competitiveness under Ramon y Cajal postdoctoral fellowship number RYC-2013-14717. Carles Hernandez is jointly funded by the Spanish Ministry of Economy and Competitiveness and FEDER funds through grant TIN2014-60404-JIN.Peer ReviewedPostprint (author's final draft

Harriaren egituraren zenbakizko eredua artezketan

The behaviour of the wheel when grinding stems in a way from the nature of its granular structure. Current grinding wheels are porous conglomerates of hard abrasive grains bonded by the formed by the binder. The characteristics of the abrasive grits, the resistance of the bonding material, together with the porous network, deter-mines wheel’s performance. The know how of wheel manufacturers is kept zealously in secret. The mechanical properties of the wheel, as an engineered material, should be able to be predicted in advance. However, its complex heterogeneous nature hinders the modelling. Recently, the discrete element method has been successfully applied in the modelling of the grinding wheel. This paper describes the proper creation proce-dure of the model. The work includes the calibration procedure of mechanical proper-ties due to homogenisation.; Harriaren portaera artezketa eragiketan, hein handi batean, bere egitura granularraren naturatik datorkio. Gaur egungo harriak aglomeratzaileak batzen dituen ale urratzaile gogorrez osatutako diseinuzko konglomeratu porotsuak dira. Alearen ezaugarriek, aglomeratzailearen erresistentziak eta, poroekin batera, hiruren arteko pro-portzioak harriaren izaera baldintzatzen dute. Ekoizpen prozesua erdi-sekretua izan ohi da, ekoizlearen urteetako esperientziaren emaitza. Harriaren propietate mekanikoak, di-seinuzko material izaki, aurrez ezagutu ahal izan beharko lirateke. Hala ere, bere natura heterogeneo konplexuak modelizazioa zailtzen du. Berriki, elementu diskretuen meto-doa aplikatu da harriaren portaera simulatzeko. Lan honetan eredua eraikitzeko proze-dura berria aurkezten da. Lanak propietate mekanikoen homogeneizazio prozesua ere azaltzen du

2-Deoxy-D-glucose couples mitochondrial DNA replication with mitochondrial fitness and promotes the selection of wild-type over mutant mitochondrial DNA

Pathological variants of human mitochondrial DNA (mtDNA) typically co-exist with wild-type molecules, but the factors driving the selection of each are not understood. Because mitochondrial fitness does not favour the propagation of functional mtDNAs in disease states, we sought to create conditions where it would be advantageous. Glucose and glutamine consumption are increased in mtDNA dysfunction, and so we targeted the use of both in cells carrying the pathogenic m.3243A>G variant with 2-Deoxy-D-glucose (2DG), or the related 5-thioglucose. Here, we show that both compounds selected wild-type over mutant mtDNA, restoring mtDNA expression and respiration. Mechanistically, 2DG selectively inhibits the replication of mutant mtDNA; and glutamine is the key target metabolite, as its withdrawal, too, suppresses mtDNA synthesis in mutant cells. Additionally, by restricting glucose utilization, 2DG supports functional mtDNAs, as glucose-fuelled respiration is critical for mtDNA replication in control cells, when glucose and glutamine are scarce. Hence, we demonstrate that mitochondrial fitness dictates metabolite preference for mtDNA replication; consequently, interventions that restrict metabolite availability can suppress pathological mtDNAs, by coupling mitochondrial fitness and replication.publishedVersio

MMP-12, Secreted by Pro-Inflammatory Macrophages, Targets Endoglin in Human Macrophages and Endothelial Cells

Upon inflammation, monocyte-derived macrophages (MF) infiltrate blood vessels to regulate several processes involved in vascular pathophysiology. However, little is known about the mediators involved. Macrophage polarization is crucial for a fast and e cient initial response (GM-MF) and a good resolution (M-MF) of the inflammatory process. The functional activity of polarized MF is exerted mainly through their secretome, which can target other cell types, including endothelial cells. Endoglin (CD105) is a cell surface receptor expressed by endothelial cells and MF that is markedly upregulated in inflammation and critically involved in angiogenesis. In addition, a soluble form of endoglin with anti-angiogenic activity has been described in inflammation-associated pathologies. The aim of this work was to identify components of the MF secretome involved in the shedding of soluble endoglin. We find that the GM-MF secretome contains metalloprotease 12 (MMP-12), a GM-MF specific marker that may account for the anti-angiogenic activity of the GM-MF secretome. Cell surface endoglin is present in both GM-MF and M-MF, but soluble endoglin is only detected in GM-MF culture supernatants. Moreover, MMP-12 is responsible for the shedding of soluble endoglin in vitro and in vivo by targeting membrane-bound endoglin in both MF and endothelial cells. These data demonstrate a direct correlation between GM-MF polarization, MMP-12, and soluble endoglin expression and function. By targeting endothelial cells, MMP-12 may represent a novel mediator involved in vascular homeostasis.Ministerio de Ciencia, Innovación y Universidades of Spain (SAF2013-43421-R to C.B.; SAF2017-83785-R and SAF2014-23801 to A.L.C.)Consejo Superior de Investigaciones Cientificas (201920E022 to C.B.)Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER; ISCIII-CB06/07/0038 to C.B.)Czech Republic Specific University Research (SVV-260414 to P.N.)CIBERER is an initiative of the Instituto de Salud Carlos III (ISCIII) of Spain supported by FEDER fundsM.A. was funded with a fellowship from Ministerio de Ciencia e Innovación (BES-2008-003888)M.V. was supported by a short-term mobility fellowship from the European Erasmus Programm