ASlib: A Benchmark Library for Algorithm Selection

The task of algorithm selection involves choosing an algorithm from a set of algorithms on a per-instance basis in order to exploit the varying performance of algorithms over a set of instances. The algorithm selection problem is attracting increasing attention from researchers and practitioners in AI. Years of fruitful applications in a number of domains have resulted in a large amount of data, but the community lacks a standard format or repository for this data. This situation makes it difficult to share and compare different approaches effectively, as is done in other, more established fields. It also unnecessarily hinders new researchers who want to work in this area. To address this problem, we introduce a standardized format for representing algorithm selection scenarios and a repository that contains a growing number of data sets from the literature. Our format has been designed to be able to express a wide variety of different scenarios. Demonstrating the breadth and power of our platform, we describe a set of example experiments that build and evaluate algorithm selection models through a common interface. The results display the potential of algorithm selection to achieve significant performance improvements across a broad range of problems and algorithms.Comment: Accepted to be published in Artificial Intelligence Journa

Arte e megaeventos esportivos no Rio de Janeiro: contranarrativas na cidade turística

Este trabalho se fundamenta no contexto da Copa do Mundo de Futebol de 2014 e dos Jogos Olímpicos Rio 2016. Procura elencar suas contradições inerentes para desenvolver as ideias de cidade-mercadoria, gentrificação e de uma cidade turística excludente para os seus cidadãos. A teoria das controvérsias de Bruno Latour é um dos métodos utilizados que procurou evidenciar as contradições fundamentais destes megaeventos no Brasil. O sentido de contrapoder em Foucault e sua ideia de resistência se aliam ao debate como forma de situar o viés político da arte e dos artistas aqui pesquisados que ofereciam uma contranarrativa à presença destes megaeventos. Para a coleta de dados foram adotadas entrevistas; recorri à memória de uma vivência com grupos ativistas e à minha própria experiência artística, a partir de 2013, nas ruas da cidade do Rio de Janeiro. As jornadas de junho de 2013 também foram chave, portanto, para entender a arte e as ações estético-políticas que questionavam os modelos de megaeventos esportivos na cidade e ofereciam uma espécie de resposta a estes espetáculos totalizantes. A filosofia da diferença de Deleuze e Guatarri e a noção de hostilidade em Derrida também foram importantes para o entendimento do turismo em sua forma mais abrangente e humana, como fenômeno social. Para isso, os escritos radicais de Hakim Bey foram fonte para crítica a uma ideia de turismo convencional ou hegemônico/capitalista e o estudo dos museus, dos espaços autônomos de arte contemporânea e das políticas públicas culturais serviram como plataforma vital de entendimento do contexto que unia estes dois campos do saber: o turismo e as artes. Recorri aos estudos dos autores destas áreas específicas como John Urry no turismo e Jacques Rancière nas artes para estabelecer uma relação de conhecimento, a partir dos conceitos de território, mobilidade, ocupações e insurreições urbanas cujo cenário do Rio de Janeiro em 2014 e 2016 se inseriaThis work is based on the context of the 2014 FIFA World Cup and the Rio 2016 Olympic Games. It seeks to highlight its inherent contradictions in order to develop the ideas of city-merchandise, gentrification and a tourist city excluding its citizens. Bruno Latour's controversy theory is one of the methods used to highlight the fundamental contradictions of these mega-events in Brazil. The sense of counter power in Foucault and his idea of resistance allied themselves with the debate as a way of situating the political bias of the art and of the artists researched here that offered a counter-narrative to the presence of these mega-events. Data were collected for interviews; I used the memory of an experience with activist groups and my own artistic experience, starting in 2013, on the streets of the city of Rio de Janeiro. The days of June 2013 were also key, therefore, to understand the art and the aesthetic-political actions that questioned the models of mega-sport events in the city and offered a kind of response to these totalizantes spectacles. The philosophy of Deleuze and Guatarri's difference and the notion of hostility in Derrida were also important for the understanding of tourism in its most comprehensive and human form as a social phenomenon. Hakim Bey's radical writings were critical for an idea of conventional or hegemonic/capitalist tourism, and the study of museums, autonomous spaces of contemporary art, and public cultural policies served as a vital platform for understanding the context that united these two fields of knowledge: tourism and the arts. I have studied the authors of these specific areas such as John Urry in tourism and Jacques Rancière in the arts to establish a relationship of knowledge, based on the concepts of territory, mobility, occupations and urban insurrections whose scenario of Rio de Janeiro in 2014 and 2016199f

Tamm plasmon-polaritons in a metal coated porous silicon photonic crystal

International audienceWe report the realization of a Tamm plasmon resonance in a planar structure by deposition of a gold film on a one-dimensional photonic crystal made of mesoporous silicon. The observation of a dip in the reflectance as well as a singularity in the ellipsometric angles confirms the presence of Tamm plasmon-polaritons with a higher quality factor than previously reported for porous Tamm structures. The simple electrochemical fabrication process of the porous silicon multilayer has the potential to facilitate the advent of integrated Tamm sensors by allowing an analyte to diffuse to the region where the electromagnetic field enhancement is highest while being low-cost and potentially CMOS-compatible

Capabilities and Limits to Form High Aspect-Ratio Microstructures by Molding of Borosilicate Glass

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Enhanced Coherent Thermal Emission From SiO 2 on a Porous Silicon Photonic Crystal

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Tamm phonon-polaritons: Localized states from phonon-light interactions

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A practical Tamm plasmon sensor based on porous Si

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Earlobe arterialized capillary blood gas analysis in the intensive care unit:a pilot study

BACKGROUND: Earlobe arterialized capillary blood gas analysis can be used to estimate arterial gas content and may be suitable for diagnosis and management of critically ill patients. However, its utility and applicability in the ICU setting remains unexplored. METHODS: A prospective observational validation study was designed to evaluate this technique in a cohort of mechanically ventilated adult critically ill patients admitted to a polyvalent ICU. Precision and agreement between capillary gas measures and arterial references was examined. Acute Respiratory Distress Syndrome (ARDS) diagnosis capabilities with the proposed technique were also evaluated. Finally, factors associated with sampling failure were explored. RESULTS: Fifty-five patients were included into this study. Precision of capillary samples was high (Coefficient of Variation PO(2) = 9.8%, PCO(2) = 7.7%, pH = 0.3%). PO(2) measures showed insufficient agreement levels (Concordance Correlation Coefficient = 0.45; bias = 12 mmHg; percentage of error = 19.3%), whereas better agreement was observed for PCO(2) and pH (Concordance Correlation Coefficient = 0.94 and 0.93 respectively; depreciable bias; percentage of error 11.4% and 0.5% respectively). The sensitivity and specificity for diagnosing ARDS were 100% and 92.3% using capillary gasometric measures. Sampling was unsuccessful in 43.6% of cases due to insufficient blood flow. Age > 65 years was independently associated with failure (odds ratio = 1.6), however hemodynamic failure and norepinephrine treatment were also influencing factors. CONCLUSIONS: Earlobe capillary blood gas analysis is precise and can be useful for detecting extreme gasometrical values. Diagnosis of ARDS can be done accurately using capillary measurements. Although this technique may be insufficient for precise management of patients in the ICU, it has the potential for important benefits in the acute phase of various critical conditions and in other critical care arenas, such as in emergency medicine, advanced medical transport and pre-hospital critical care

Microfabricated Membranes for Radiative Near Field Measurements

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Interface engineering for vanadium dioxide (VO2) integration on silicon

International audienceNeuromorphic computing is being seen as a solution to address the memory bottleneck persistent with the present computing paradigm. Artificial synapses and neurons need to be built to realize such an architecture. One way to emulate a bio-synapse requires a material with a metal-insulator phase transition (MIT). VO2 undergoes a structural phase transformation (SPT) from a monoclinic structure at room temperature to tetragonal at approximately 70°C. The SPT is accompanied by an MIT leading to a large variation in its electrical (about 4 orders of magnitude of its resistivity) and optical properties, in particular, in its complex refractive index in the mid-IR frequency range. To keep with the current trends of the microelectronic industry, it is imperative to integrate VO2 on silicon. However, the higher lattice mismatch and formation of oxides and silicates at the interface between VO2 and crystalline Si degrade the quality and functionality of VO2 film. Additionally, VO2(M1) is a challenging material to integrate into patterned heterostructures because it can exist not only as multiple polymorphs (A, B, M1) but the high-temperature depositions can lead to the formation of various oxidation states phases that are present in the V-O system (VnO2n-1, VnO2n 1). This work was conducted to study the growth of VO2 on silicon with oxide buffer layers using RF magnetron sputtering of a V2O5 ceramic target in an argon atmosphere. We studied the structure-property relationships, specifically electrical and optical properties as a function of temperature across the Tc. Structural and compositional characterization are carried out using x-ray diffraction, atomic force microscopy, and x-ray photoemission spectroscopy respectively, optical responses are studied under spectroscopic ellipsometry and electrical characterizations are performed using the four-point probe method. With the use of a very thin metal oxide buffer layer between the silicon substrate and VO2 film, we demonstrate a high resistivity ratio (of the order 3 between the two phases) and investigate the scope of improvement. The results show the influence of substrate temperature, VO2 grain size, and strain on it as well as the crystal structure of the buffer layer on the structural and physical properties of interfaces and film morphology which subsequently affect the electrical bistability of VO2. The preliminary findings mentioned here are being utilized to improve the electrical bistability, thus allowing us to improve the reproducibility in operational modes (switching, memory, logical operations, etc.) of neuromorphic devices