HPC Cloud for Scientific and Business Applications: Taxonomy, Vision, and Research Challenges

High Performance Computing (HPC) clouds are becoming an alternative to on-premise clusters for executing scientific applications and business analytics services. Most research efforts in HPC cloud aim to understand the cost-benefit of moving resource-intensive applications from on-premise environments to public cloud platforms. Industry trends show hybrid environments are the natural path to get the best of the on-premise and cloud resources---steady (and sensitive) workloads can run on on-premise resources and peak demand can leverage remote resources in a pay-as-you-go manner. Nevertheless, there are plenty of questions to be answered in HPC cloud, which range from how to extract the best performance of an unknown underlying platform to what services are essential to make its usage easier. Moreover, the discussion on the right pricing and contractual models to fit small and large users is relevant for the sustainability of HPC clouds. This paper brings a survey and taxonomy of efforts in HPC cloud and a vision on what we believe is ahead of us, including a set of research challenges that, once tackled, can help advance businesses and scientific discoveries. This becomes particularly relevant due to the fast increasing wave of new HPC applications coming from big data and artificial intelligence.Comment: 29 pages, 5 figures, Published in ACM Computing Surveys (CSUR

Caracterização física química de raízes de mandiocaba.

A mandioca (Manihot esculenta Crantz) é um arbusto de origem brasileira (sudoeste da Amazônia) e que, mesmo antes da chegada dos europeus à América, já estava disseminado para o cultivo alimentar, apresentando diversidades de variedades. Cultivada nas mais diversas regiões do Brasil, sua produção tem sido dirigida tanto para consumo direto como para indústria de transformação. Portanto, objetivou-se avaliar as características físico-químicas das raízes de mandiocaba. Para tal, foram avaliados os teores de umidade 90%, cinzas 0,1%, fibra 0,4%, proteína bruta 0,15%, lipídios totais 0,09%, acidez titulável total 2,2, pH 6,3, sólidos solúveis totais 6,3, açúcar redutor 3,9 e açúcares redutores totais 5,2. Portanto pode-se concluir que a raiz de mandioca doce apresenta atributos que a qualificam para serem utilizadas diretamente para serem fermentadas por leveduras para a obtenção de etanol. Cumpre ressaltar que o rendimento em etanol será proporcional a quantidade de açúcar que existir na raiz de mandioca doce

Revestimentos decorativos pelo efeito SPR obtido pela adição de Au a matrizes dieléctricas

A SPR (ressonância dos plasmões de superfície) originada pela introdução de nanopartículas metálicas em matrizes dieléctricas possui um elevado leque de aplicações, sendo alvo de uma actividade intensa de investigação. De modo a tirar partido da forte extinção da luz em certas gamas do visível que estes sistemas proporcionam, foi objectivo deste trabalho desenvolver revestimentos nanocompósitos com efeito SPR para aplicações decorativas. Para tal, recorreu-se à técnica de pulverização catódica reactiva para depositar os revestimentos nanocompósitos consistindo em nanopartículas de Au dispersas em matrizes de WO3 e Al2O3. Por outro lado, pela aplicação de tratamentos térmicos pós-deposição foi promovido o crescimento das nanopartículas de Au. A incorporação crescente de diferentes teores em Au na matriz permitiu a presença de nanopartículas com tamanhos maiores. Além disso, os tratamentos térmicos influenciaram com sucesso o crescimento das nanopartículas de Au na matriz, permitindo alterar a posição, forma e intensidade dos picos de SPR e, onsequentemente, a coloração obtida para as amostras. Contudo, também as propriedades estruturais e dieléctricas da matriz foram afectadas pela temperatura de recozimento, como por exemplo um aumento do índice de refracção que promoveu um deslocamento da posição dos picos de SPR para o “vermelho” (sistema W-O+Au). Nos resultados alcançados houve por isso um efeito combinado entre o crescimento das nanopartículas e a variação do índice de refracção da matriz. Através da variação de três parâmetros, matriz, composição química e temperatura de recozimento, foi possível depositar revestimentos nanocompósitos de WO3+Au e AlO+Au com diferentes cores pelo ajuste dos picos de SPR das nanopartículas de Au.The deposition of thin films consisting of metallic clusters embedded in dielectric matrixes can originate a strong SPR (Surface Plasmon Resonance) signal that has a wide range of applications, being the subject of an intense research nowadays. The main idea of this research work was to utilize the strong extinction of light that arises in these systems in certain zones of the visible spectrum for decorative coatings. Nanocomposite coatings consisting of Au clusters embedded in a WO3 or Al2O3 matrix were prepared by reactive sputtering with different Au contents. The higher the Au contents in the coatings the larger the nanoparticles were. By further annealing these samples at increasing temperatures, the Au segregation in the matrix was promoted. Both events permit to determine the SPR peak position along with its shape and intensity and, consequently, the optical properties of the coatings. Moreover, the thermal treatments also influenced the optical characteristics of the matrix, e.g. the refractive index was increased, leading to the redishing of the SPR position. Thus, the final results attained in the SPR peak shape, intensity and position for each case were mainly due to a combined effect between the Au cluster size and the refractive index of the oxide matrix. By varying the three major experimental parameters, the oxide matrix, the Au composition and the annealing temperature, it was possible to achieve nanocomposite coatings of WO3+Au and AlO+Au with different colours by tailoring the SPR peak shape and position.FCT - DECOMAT (PTDC/CTM/70037/2006), FEDER, através do programa COMPETE - Programa Operacional Factores de Competitividade

2,6-Diiodo-4-nitrophenol, 2,6-diiodo-4-nitrophenyl acetate and 2,6-diiodo-4-nitroanisole: interplay of hydrogen bonds, iodo-nitro interactions and aromatic [pi]-[pi]-stacking interactions to give supramolecular structures in one, two and three dimensions

Peer reviewedPublisher PD

Características físico-químicas de raízes de mandioca mansa (Manihot esculenta Crantz).

A mandioca apresenta uma grande diversidade genética e a caracterização físico-química é uma importante ferramenta de avaliação para poder selecionar genótipos promissores para fins de melhoramento genético. Por isso, objetivou-se caracterizar diferentes genótipos de mandioca mansa pertencentes ao banco ativo de germoplasma (BAG) da Embrapa Amazônia Oriental, no qual, foram coletados 12 genótipos de raízes de mandioca mansa em triplicata, pertencentes ao BAG-Embrapa, Belém, Pará, Brasil. Após a colheita das raízes, estas passaram por lavagem, descasque e armazenamento até o momento de utilização nas analises físico-químicas. O teor de proteínas variou entre 0,4-1,3%; lipídios 0,3-1,9%; umidade 55,3-64,4%; cinzas 0,4-0,6%; fibras 0,4-1,2%;carboidratos 32,4-42,7%; pH 6,6-7,0 e sólidos solúveis totais entre 1,0-1,4 ºBrix. Com exceção de cinzas, fibras e pH, os demais parâmetros apresentaram diferenças significativas. Tais características podem variar devido às propriedades intrínsecas das raízes de mandioca, em relação aos seus diferentes genótipos

W/AlSiTiNx/SiAlTiOyNx/SiAlOx multilayered solar thermal selective absorber coating

Solar thermal energy has often been used as a renewable green energy source. Here we present a design composed of a highly selective solar thermal absorber coating that has been deposited by DC magnetron sputtering. This will consist of four layers: W/AlSiTiNx/SiAlTiOyNx/SiAlOx. The coating that was utilised revealed an excellent average solar thermal absorbance, (alpha = 95.5%) with very low emittance, (epsilon = 9.6% calculated for 500 degrees C) together with an excellent thermal stability after annealed at 500 degrees C, in air for 350 h, and at 630 degrees C in vacuum for 220 h.FCT in the framework of the Strategic Funding UID/FIS/04650/2013 and the financial support of FCT, POCI and PORL operational programs through the project POCI01-0145-FEDER-016907 (PTDC/CTM-ENE/2892/2014), co-financed by European community fund FEDER

Author's Preface

This paper is focused on the structure, chemical composition, optical and mechanical properties of coatings consisting in an Alsingle bondN matrix incorporating different Au contents (up to 2.5 at.%). The Au was incorporated in the matrix atomically or in the form of very small nanoparticles (< 1 nm). With the increase in the Au content both the refractive index and the coefficient of extinction were increased. The AlN matrix presented a crystalline wurtzite phase, stable up to 1000 °C. With annealing at 400 °C the precipitation of XRD detectable Au nanoparticles was possible, originating SPR light absorption. The Alsingle bondN + Au coatings exhibited hardness values between 15 and 24 GPa, with no significant changes after the annealing treatments at low temperatures. These coatings are of interest to the decorative applications

Estudos de Solos do Município de Aceguá, RS

bitstream/item/130155/1/Circular-157.pd

Functional and optical properties of Au :TiO2 nanocomposite films : the influence of thermal annealing

A set of nanocomposite thin films consisting of Au nanoclusters dispersed in a TiO2 dielectric matrix was deposited by reactive magnetron sputtering, and subjected to thermal annealing in vacuum, at temperatures ranging from 200 to 800 ◦C. The obtained results show that the structure and the size of Au clusters, together with the matrix crystallinity, changed as a result of the annealing, and were shown to be able to change the optical properties of the films and keeping good mechanical properties, opening thus a wide number of possible applications. The crystallization of the gold nanoclusters induced by the annealing was followed by a systematic change in the overall coating behaviour, namely the appearance of surface plasmon resonance (SPR) behaviour. This effect enables to tailor the thin films reflectivity, absorbance and colour coordinates, contributing to the importance of this thin film system. The different attained optical characteristics (reflectance values ranging from interference to metallic-like behaviours and colour varying for interference rainbow-like to several tones of red-brownish), associated with a reasonable mechanical resistance of the coatings (good adhesion to different substrates and hardness values ranging from 5 to 7.5 GPa), induce the possibility to use this film system in a wide range of decorative applications.Fundac¸ ão para a Ciência e Tecnologia (FCT) - PTDC/CTM/70037/2006