469 research outputs found
Software Analysis: A point of view of a car manufacturer
International audienceThis paper presents a point of view on the way and works that Renault considers as necessary to insure a good level of software quality through the application of solutions concerning static code analysis and intrusive control of the software development by quality requirements and software verification levels to the supplier
Experimental evaluation of R410A, R407C and R134a alternative refrigerants in residential heat pumps
Protocols and regulations such as the Montreal Protocol (1987), the Kyoto Protocol (1997), the European F-gas regulation (2006) and now its revision (2014) cause a shift toward refrigerants with both zero Ozone Depletion Potential (ODP) and low Global Warming Potential (GWP). Alternative refrigerants with low-GWP are under investigation for residential heat pumps, air-conditioners and heat pump water heaters as R410A, R407C and R134a have GWP of 2088, 1650 and 1430, respectively. In this study, five alternative refrigerants: R459A, R454B, R447A, HPR2A and R32, with GWP of 460, 466, 583, 600 and 675, respectively, were investigated for the replacement of R410A in a 10 kW Air-to-Water (A/W) reversible heat pump. Two alternative refrigerants of R134a: R1234yf and R513A with GWP of 4 and 631, respectively, were tested in a split Heat Pump Water Heater (HPWH) having a water tank of 200 L. R454C with a GWP of 148 was evaluated as a possible alternative to R407C in a 3 kW Water-to-Air (W/A) reversible heat pump. To assess and to compare the performances, drop-in tests were carried out. For each heat pump and refrigerant, a charge optimization was performed prior to the performance tests and finally, a performance verification using the base refrigerant was carried out to detect any anomaly after the use of each alternative refrigerant. For the A/W and the W/A heat pumps, the tests were performed according to the EN 14511 standard and for the HPWH, the tests consisted in heating up of the tank. During all tests, measurements allowed the determination of cooling / heating capacities, electric power inputs and efficiencies (EER/ COP). Refrigerant pressures and discharge temperature were also recorded. A total of 8 alternative refrigerants with low-GWP were evaluated with not less than 114 performance tests. The experimental results are useful for the HVAC community for facilitating the selection of the most promising candidates for drop-in replacement of R410A, R134a and R407C
Technical and Economic Analysis of a Residential Heat Pump with Photovoltaic Solar Panels in Self-Consumption for Space Heating, Cooling and DHW Production
Two different thermodynamic systems for space heating, cooling, and domestic hot water production coupled to photovoltaic panels have been studied. The aim is to assess the PV electricity self-consumption variation with the heat storage volume and the applied control strategy. Each system has been studied using a 1D unsteady state modelisation software to simulate its performance in a house complying with the French building code (RT2012) having a DHW demand according to ErP’s load profile M and with Paris weather data. The main parameters studied are the electricity consumption of the thermodynamic system, the seasonal performance factor (SPF), the self-consumption ratio, the self-production ratio, the coverage ratio and the Return on Investment. The results show that the seasonal efficiency can be doubled thanks to the optimization of the PV electricity self-consumption, which results in a return on investment lower than 15 years
Evaluation of R-410A refrigerant alternatives in a residential reversible air to water heat pump
Protocols and regulations such as the Montreal Protocol (1987), the Kyoto Protocol (1997), the European F-gas regulation (2006) and now its revision (2014) cause a shift toward refrigerants with both zero Ozone Depletion Potential (ODP) and low Global Warming Potential (GWP). Alternative refrigerants with low-GWP are under investigation for residential heat pumps and air-conditioners as R-410A has a GWP of 2088. In this study, two promising alternative refrigerants with a low-GWP, DR-5A (R-454B) and L41-2 (R-447A), both HFC-HFO mixtures with a GWP of 466 and 583 respectively, have been tested in a residential heat pump. Ă‚ To assess and to compare the heat pump performances using R-410A, DR-5A and L41-2, drop-in tests have been carried out in a 10 kW air-to-water reversible heat pump. For each refrigerant, the heat pump performances have been assessed for 2 rating conditions and 2 operating limit conditions in the cooling mode and for 6 rating conditions and 3 operating limit conditions in the heating mode. The tests have been performed according to the ENĂ‚ 14511 standard. This experimental investigation has been carried out in three phases. In the first one, the performances of the heat pump using R-410A have been evaluated. Then, in phases 2 and 3, both alternative refrigerants, DR-5A and L41-2, have been tested. For each, a refrigerant charge optimization has been done, then the rating and operating limit condition tests have been performed, and finally, a performance verification using R-410A has been carried out to detect any anomaly after the use of one or the other of these alternative refrigerants. During all the tests, measurements have allowed to determine the thermal capacities, the electric energy consumptions, the efficiencies (EER or COP), as well as the refrigerant circuit pressures and discharge temperatures. Ă‚ A total of 39 tests have been performed. The refrigerant charge optimization drives to decrease the charge in the heat pump by 15% for DR-5A and by 21% for L41-2 in comparison with R-410A. The results show that R-410A replacement by L41-2 and DR-5A do not raise any particular problem even in operating limit condition tests and the performances obtained are, aside from some exceptions, almost equivalent (+/- 10%) to those of R-410A. Globally, DR-5A shows higher capacities and performances than L41-2
Dankesworte: Hamburg - Bordeaux, auch ein Beitrag zum Europa des Wissens und der Vernunft
Die seit einem halben Jahrhundert bestehende Partnerschaft zwischen den Universitäten Hamburg und Bordeaux hat ihre praktische Umsetzung in vielerlei Formen gefunden. Vor allem zwei Gründe gaben den Ausschlag, dass jetzt zum ersten Mal in der langen Partnerschaftsgeschichte ein Jubiläum feierlich begangen wurde.
Der eine davon war das Erscheinen eines umfangreichen, in enger Hamburg-Bordelaiser Historiker-Kooperation entstandenen Jubiläumsbandes. Den anderen Anlass bot die Verleihung der Würde eines Ehrendoktors der Universität Hamburg durch das Department Sprache, Literatur, Medien (SLM) II an den Bordelaiser Germanisten Jean Mondot für seine der europäischen Aufklärung insbesondere in Deutschland geltenden, Maßstäbe setzenden Forschungen.The partnership between the Universities of Hamburg and Bordeaux, which has existed for half a century, has been put into practice in many forms. There were two main reasons for the fact that this is the first time in the long history of partnership that an anniversary has been celebrated.
One of these was the publication of an extensive anniversary volume, which was produced in close cooperation with the Hamburg-Bordelais historians. The other occasion was the conferral of an honorary doctorate from the University of Hamburg by the Department of Language, Literature and Media (SLM) II to the Bordelaiser German scholar Jean Mondot for his research on European Enlightenment, which set new standards, particularly in Germany
Profiling the T Cell Receptor Alpha/Delta Locus in Salmonids
In jawed vertebrates, two major T cell populations have been characterized. They are defined as α/β or γ/δ T cells, based on the expressed T cell receptor. Salmonids (family Salmonidae) include two key teleost species for aquaculture, rainbow trout (Oncorhynchus mykiss) and Atlantic salmon (Salmo salar) which constitute important models for fish immunology and important targets for vaccine development. The growing interest to decipher the dynamics of adaptive immune responses against pathogens or vaccines has resulted in recent efforts to sequence the immunoglobulin (IG) or antibodies and T cell receptor (TR) repertoire in these species. In this context, establishing a comprehensive and coherent locus annotation is the fundamental basis for the analysis of high-throughput repertoire sequencing data. We therefore decided to revisit the description and annotation of TRA/TRD locus in Atlantic salmon and two strains of rainbow trout (Swanson and Arlee) using the now available high-quality genome assemblies. Phylogenetic analysis of functional TRA/TRD V genes from these three genomes led to the definition of 25 subgroups shared by both species, some with particular feature. A total of 128 TRAJ genes were identified in Salmo, the majority with a close counterpart in Oncorhynchus. Analysis of expressed TRA repertoire indicates that most TRAV gene subgroups are expressed at mucosal and systemic level. The present work on TRA/TRD locus annotation along with the analysis of TRA repertoire sequencing data show the feasibility and advantages of a common salmonid TRA/TRD nomenclature that allows an accurate annotation and analysis of high-throughput sequencing results, across salmonid T cell subsets
ATOME : a blackboard architecture with temporal and hypothetical reasoning
To cope with high level AI-based applications as signal understanding, process control or decision making, an AI system must take into account various knowledge sources and reasoning schemes. In this paper, we propose a blackboard-based architecture which achieves opportunism and efficiency while controlling multiple knowledge sources. In addition it integrates temporal and hypothetical reasoning to deal with applications evolving in time, and manipulating noisy or errorfull information
Software Quality Objectives for Source Code
International audienceThe MathWorks - Renault SA - PSA Peugeot Citroën - Delphi Diesel System - Valeo group wrote together a code quality standard from scratch. This document describes how the code standard places the proof of absence of run-time errors at the centre of its software quality model. It details how the following elements of the quality model co-exist together with the supplier code life cycle: MISRA-C coding standard, the absence of run-time errors and some code complexity metrics. Additionally, this document describes how the Automotive manufacturers and the suppliers have to agree on and achieve different Software Quality Objectives according to the code life cycle stage and the safety aspects of the application.Finally, the document illustrates that standard with the PolySpace product and details how the product can help both the automotive manufacturer and the supplier working with this standard
Evolution of T cell receptor beta loci in salmonids
T-cell mediated immunity relies on a vast array of antigen specific T cell receptors (TR). Characterizing the structure of TR loci is essential to study the diversity and composition of T cell responses in vertebrate species. The lack of good-quality genome assemblies, and the difficulty to perform a reliably mapping of multiple highly similar TR sequences, have hindered the study of these loci in non-model organisms. High-quality genome assemblies are now available for the two main genera of Salmonids, Salmo and Oncorhynchus. We present here a full description and annotation of the TRB loci located on chromosomes 19 and 25 of rainbow trout (Oncorhynchus mykiss). To get insight about variations of the structure and composition of TRB locus across salmonids, we compared rainbow trout TRB loci with other salmonid species and confirmed that the basic structure of salmonid TRB locus is a double set of two TRBV-D-J-C loci in opposite orientation on two different chromosomes. Our data shed light on the evolution of TRB loci in Salmonids after their whole genome duplication (WGD). We established a coherent nomenclature of salmonid TRB loci based on comprehensive annotation. Our work provides a fundamental basis for monitoring salmonid T cell responses by TRB repertoire sequencing
A comprehensive assessment of demographic, environmental, and host genetic associations with gut microbiome diversity in healthy individuals.
BACKGROUND: The gut microbiome is an important determinant of human health. Its composition has been shown to be influenced by multiple environmental factors and likely by host genetic variation. In the framework of the Milieu Intérieur Consortium, a total of 1000 healthy individuals of western European ancestry, with a 1:1 sex ratio and evenly stratified across five decades of life (age 20-69), were recruited. We generated 16S ribosomal RNA profiles from stool samples for 858 participants. We investigated genetic and non-genetic factors that contribute to individual differences in fecal microbiome composition. RESULTS: Among 110 demographic, clinical, and environmental factors, 11 were identified as significantly correlated with α-diversity, ß-diversity, or abundance of specific microbial communities in multivariable models. Age and blood alanine aminotransferase levels showed the strongest associations with microbiome diversity. In total, all non-genetic factors explained 16.4% of the variance. We then searched for associations between > 5 million single nucleotide polymorphisms and the same indicators of fecal microbiome diversity, including the significant non-genetic factors as covariates. No genome-wide significant associations were identified after correction for multiple testing. A small fraction of previously reported associations between human genetic variants and specific taxa could be replicated in our cohort, while no replication was observed for any of the diversity metrics. CONCLUSION: In a well-characterized cohort of healthy individuals, we identified several non-genetic variables associated with fecal microbiome diversity. In contrast, host genetics only had a negligible influence. Demographic and environmental factors are thus the main contributors to fecal microbiome composition in healthy individuals. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT01699893
- …