Tolérance aux fautes dans les systèmes autonomes

Les systèmes autonomes suscitent aujourd'hui un intérêt croissant, que ce soit dans le domaine des robots d'exploration spatiale ou dans des domaines plus proches de l'homme, tels que les robots de service. Mais se pose le problème de leur sûreté de fonctionnement : peut-on avoir une confiance justifiée dans le comportement de systèmes conçus pour prendre des décisions sans intervention humaine? L'objectif de cette thèse est de proposer des concepts architecturaux capables d'améliorer la sûreté de fonctionnement des systèmes autonomes, en particulier par la conception et le développement de mécanismes de tolérance aux fautes adaptés à la fonction de planification, centrale à l'autonomie des systèmes complexes. Une évaluation des performances et de l'efficacité des mécanismes proposés est réalisée en utilisant la technique d'injection de fautes par mutation. ABSTRACT : Autonomous systems generate today a rising interest, whether in fields such as space exploration or applications nearer to man such as medical assistants, tour guides or utonomous vehicles. However, such critical applications raise the question of their dependability : can we justifiably trust systems designed to take decisions without human intervention? The objective of this thesis is to propose architectural concepts able to improve dependability in autonomous systems. In particular, it presents the design and implementation of fault tolerance mechanisms adapted to planning, an essential functionality in autonomous systems. An evaluation of the performance and the efficacy of the proposed mechanisms is realized by fault injection through source code mutatio

In All Seriousness: Play, Knowledge, and Community in the Union of Real Art

Taking its direction from seminal works in the field of play theory, this dissertation examines ludic elements in the textual practices and intellectual community of the Union of Real Art (Ob”edinenie real’nogo iskusstva or OBeRIu). I use the concept of play to elucidate how the group used literature as an unconventional medium for the pursuit of special forms of knowledge and to explore the intimate genre of performance that shaped the association’s collective identity as a group of writers and thinkers. The four chapters that comprise this dissertation each examine one facet of how play shaped the OBeRIu’s shared literary practice. In the first chapter, I contrast the performative strategies of the OBeRIu members (or the oberiuty) with those of the Russian Futurists, demonstrating that the OBeRIu approach to spectacle possesses an ‘existential’ dimension that is quite alien to that of Futurism. I argue that Futurist performance is best characterized by what Hans-Georg Gadamer has called “aesthetic differentiation,” a hermeneutic tradition that foregrounds the autonomy of the artwork while ignoring its rootedness in broader spheres of cultural activity. In contrast, the members of the OBeRIu (the oberiuty), were engaged in what some theorists have called deep play: they showed little interest in the épatage tradition practices by the Futurists and drew no meaningful distinction between art and life.I suggest that performative strategies of the oberiuty can be productively interpreted according to Gadamer’s concept of “self-presentation,” a notion that proves immensely useful for understanding not only the group’s theater, but their written work as well. In my second chapter, I show how the OBeRIu’s playful approach to writing was underscored by their commitment to an epistemic understanding of literature: they believed that literary pursuits constitute a unique form of knowledge. I suggest that the texts produced by the oberity frustrate the boundary that supposedly distinguishes poetry and philosophy. I demonstrate how even a playfully ‘absurd’ text such as Daniil Kharms’s “Blue Notebook No. 10” can be read as a work of philosophy—in this case as a kind of performative refutation of Kantian metaphysics. I suggest that the epistemic register of OBeRIu literature can be likened to what Roger Caillois has called games of ilinx—their texts induce a kind of cognitive vertigo that pushes readers towards forms of knowledge that cannot be properly conceptualized. As a form of epistemic play, OBeRIu texts open onto the world even as they exist ‘beyond’ it, inviting readers to appreciate in poetry what Gadamer called “the joy of knowledge.” In the third chapter of this dissertation I argue that the commitment of the oberiuty to an epistemic understanding of literary art places them squarely at odds with premises fundamental to the theories of Russian Formalism. Indeed, I demonstrate how the OBeRIu as a group deliberately problematize the Formalist concept of literariness. I demonstrate that the poetic episteme of the group took direction from Russian Orthodox theology, particularly the concept of the eikon. The epistemic nature of OBeRIu ‘nonsense’ precludes interpreting their texts as exercises in Shklovskian estrangement. Instead, I suggest that Gadamer’s notion of recognition is invaluable for understanding the work of the oberiuty. Their literary work articulates something and in doing so adds to our understanding of the world. In the final chapter I consider the community of chinari, which constituted a kind of intimate ‘inner circle’ for the OBeRIu that was both more private and longer lived than the Union of Real Art itself. I suggest that the chinari circle can be understood as part of a discernible line of extra-institutional play communities in the history of Russian letters that began with the Arzamas Society of Obscure People. I argue that play was the raison d’être of the chinari community and largely defined the sense they had of themselves as an intellectual community. Considering closely Leonid Lipavsky’s Conversations, a more or less authentic record of the group’s discussions between 1933 and 1934, I suggest that the group used the speech genre of bullshit quite productively—it was both a fun way to explore ideas and, more importantly, a phenomenally effective way to foster their collective bond

Therapeutic exercise attenuates neutrophilic lung injury and skeletal muscle wasting

Early mobilization of critically ill patients with the acute respiratory distress syndrome (ARDS) has emerged as a therapeutic strategy that improves patient outcomes, such as the duration of mechanical ventilation and muscle strength. Despite the apparent efficacy of early mobility programs, their use in clinical practice is limited outside of specialized centers and clinical trials. To evaluate the mechanisms underlying mobility therapy, we exercised acute lung injury (ALI) mice for 2 days after the instillation of lipopolysaccharides into their lungs. We found that a short duration of moderate intensity exercise in ALI mice attenuated muscle ring finger 1 (MuRF1)?mediated atrophy of the limb and respiratory muscles and improved limb muscle force generation. Exercise also limited the influx of neutrophils into the alveolar space through modulation of a coordinated systemic neutrophil chemokine response. Granulocyte colony-stimulating factor (G-CSF) concentrations were systemically reduced by exercise in ALI mice, and in vivo blockade of the G-CSF receptor recapitulated the lung exercise phenotype in ALI mice. Additionally, plasma G-CSF concentrations in humans with acute respiratory failure (ARF) undergoing early mobility therapy showed greater decrements over time compared to control ARF patients. Together, these data provide a mechanism whereby early mobility therapy attenuates muscle wasting and limits ongoing alveolar neutrophilia through modulation of systemic neutrophil chemokines in lung-injured mice and humans.Fil: Files, D. Clark. School Of Medicine; Estados UnidosFil: Liu, Chun. School Of Medicine; Estados UnidosFil: Pereyra, Andrea Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner"; ArgentinaFil: Wang, Zhong Min. University Wake Forest; Estados Unidos. School Of Medicine; Estados UnidosFil: Aggarwal, Neil. Johns Hopkins Asthma And Allergy Center; Estados UnidosFil: D´Alessio, Franco. Johns Hopkins Asthma And Allergy Center; Estados UnidosFil: Garibaldi, Brian T.. Johns Hopkins Asthma and Allergy Center; Estados UnidosFil: Mock, Jason R.. Johns Hopkins Asthma and Allergy Center; Estados UnidosFil: Singer, Benjamin D.. Johns Hopkins Asthma and Allergy Center; Estados UnidosFil: Feng, Xin. Wake Forest School of Medicine; Estados UnidosFil: Yammani, Raghunatha R.. Wake Forest School of Medicine; Estados UnidosFil: Zhang, Tan. Wake Forest School of Medicine; Estados UnidosFil: Lee, Amy L.. Wake Forest School of Medicine; Estados UnidosFil: Philpott, Sydney. Wake Forest School of Medicine; Estados UnidosFil: Lussier, Stephanie. Wake Forest School of Medicine; Estados UnidosFil: Purcell, Lina. Wake Forest School of Medicine; Estados UnidosFil: Chou, Jeff. Wake Forest School of Medicine; Estados UnidosFil: Seeds, Michael. Wake Forest School of Medicine; Estados UnidosFil: King, Landon S.. Johns Hopkins Asthma and Allergy Center; Estados UnidosFil: Morris, Peter E.. Wake Forest School of Medicine; Estados UnidosFil: Delbono, Osvaldo. School Of Medicine; Estados Unido

Therapeutic exercise attenuates neutrophilic lung injury and skeletal muscle wasting

Early mobilization of critically ill patients with the acute respiratory distress syndrome (ARDS) has emerged as a therapeutic strategy that improves patient outcomes, such as the duration of mechanical ventilation and muscle strength. Despite the apparent efficacy of early mobility programs, their use in clinical practice is limited outside of specialized centers and clinical trials. To evaluate the mechanisms underlying mobility therapy, we exercised acute lung injury (ALI) mice for 2 days after the instillation of lipopolysaccharides into their lungs. We found that a short duration of moderate intensity exercise in ALI mice attenuated muscle ring finger 1 (MuRF1)–mediated atrophy of the limb and respiratory muscles and improved limb muscle force generation. Exercise also limited the influx of neutrophils into the alveolar space through modulation of a coordinated systemic neutrophil chemokine response. Granulocyte colony-stimulating factor (G-CSF) concentrations were systemically reduced by exercise in ALI mice, and in vivo blockade of the G-CSF receptor recapitulated the lung exercise phenotype in ALI mice. Additionally, plasma G-CSF concentrations in humans with acute respiratory failure (ARF) undergoing early mobility therapy showed greater decrements over time compared to control ARF patients. Together, these data provide a mechanism whereby early mobility therapy attenuates muscle wasting and limits ongoing alveolar neutrophilia through modulation of systemic neutrophil chemokines in lung-injured mice and humans.Facultad de Ciencias Médica

Extending our scientific reach in arboreal ecosystems for research and management

The arboreal ecosystem is vitally important to global and local biogeochemical processes, the maintenance of biodiversity in natural systems, and human health in urban environments. The ability to collect samples, observations, and data to conduct meaningful scientific research is similarly vital. The primary methods and modes of access remain limited and difficult. In an online survey, canopy researchers (n = 219) reported a range of challenges in obtaining adequate samples, including ∼10% who found it impossible to procure what they needed. Currently, these samples are collected using a combination of four primary methods: (1) sampling from the ground; (2) tree climbing; (3) constructing fixed infrastructure; and (4) using mobile aerial platforms, primarily rotorcraft drones. An important distinction between instantaneous and continuous sampling was identified, allowing more targeted engineering and development strategies. The combination of methods for sampling the arboreal ecosystem provides a range of possibilities and opportunities, particularly in the context of the rapid development of robotics and other engineering advances. In this study, we aim to identify the strategies that would provide the benefits to a broad range of scientists, arborists, and professional climbers and facilitate basic discovery and applied management. Priorities for advancing these efforts are (1) to expand participation, both geographically and professionally; (2) to define 2–3 common needs across the community; (3) to form and motivate focal teams of biologists, tree professionals, and engineers in the development of solutions to these needs; and (4) to establish multidisciplinary communication platforms to share information about innovations and opportunities for studying arboreal ecosystems

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

Tolérance aux fautes dans les systèmes autonomes

Les systèmes autonomes suscitent aujourd'hui un intérêt croissant, que ce soit dans le domaines des robots d'exploration spatiale ou dans des domaines plus proches de l'homme, tels que les robots de service. Mais se pose le problème de leur sûreté de fonctionnement : peut-on avoir une confiance justifiée dans le comportement de systèmes conçus pour prendre des décisions sans intervention humaine ? L'objectif de cette thèse est de proposer des concepts architecturaux capables d'améliorer la sûreté de fonctionnement des systèmes autonomes, en particulier par la conception et le développement de mécanismes de tolérance aux fautes adaptés à la fonction de planification centrale à l'autonomie des systèmes complexes. Une évaluation des performances et de l'efficacité des mécanismes proposés est réalisée en utilisant la technique d'injection de fautes par mutation.Autonomous systems generate today a rising interest, whether in fields such as space exploration or applications nearer to man such as medical assistants, tour guides or autonomous vehicles. However, such critical applications raise the question of their dependability : can we justifiably trust systems designed to take decisions without human intervention ? The objective of this thesis is to propose architectural concepts able to improve dependabiblity in autonomous systems. In particular, it presents the design and implementation of fault tolerance mechanisms adapted to planning, an essential functionality in autonomous systems. An evaluation of the performance and the efficacy of the proposed mechanisms is realized by fault injection through source code mutation.TOULOUSE-ENSEEIHT (315552331) / SudocSudocFranceF

Functional Diversification for Software Fault Tolerance in Data Fusion: a real Application on Kalman Filters for Mobile Robot Yaw Estimation

International audienceIn this paper, we propose a software fault tolerant architecture for data fusion mechanisms. Our work is motivated by the difficulty to validate fusion mechanisms, either through formal approaches or testing. The proposed mechanism is based on functional diversification using the well known N-versions Programming approach, to tolerate faults in data fusion models.The general principle of our approach is to implement three diversified data fusion mechanisms, each with forcibly diversified models and independent inputs. With this diversification and a voting mechanism, our architecture provides the following fault tolerance services: software error detection, software error diagnosis and system recovery.To demonstrate the efficiency of our approach, we present a real case study consisting in estimating a mobile robot’s yaw angle using odometers and gyroscopes with a Kalman Filter. We present a fault tolerance evaluation that is based on real data acquisition by an intelligent sensor equipped vehicle (Citroen C5), this real data offline replay, and fault injection techniques.In our opinion, the main original contribution of this paper is to propose software fault tolerance mechanisms in data fusion, which are rarely considered in the literature. Indeed, we believe that these faults can have an important impact on the system’s behavior, are difficult to detect and eliminate through validation, and are prone to appear considering that empirical values (such as gains or belief mass functions) are used in data fusion