On modular decompositions of system signatures

Considering a semicoherent system made up of $n$ components having i.i.d. continuous lifetimes, Samaniego defined its structural signature as the $n$-tuple whose $k$-th coordinate is the probability that the $k$-th component failure causes the system to fail. This $n$-tuple, which depends only on the structure of the system and not on the distribution of the component lifetimes, is a very useful tool in the theoretical analysis of coherent systems. It was shown in two independent recent papers how the structural signature of a system partitioned into two disjoint modules can be computed from the signatures of these modules. In this work we consider the general case of a system partitioned into an arbitrary number of disjoint modules organized in an arbitrary way and we provide a general formula for the signature of the system in terms of the signatures of the modules. The concept of signature was recently extended to the general case of semicoherent systems whose components may have dependent lifetimes. The same definition for the $n$-tuple gives rise to the probability signature, which may depend on both the structure of the system and the probability distribution of the component lifetimes. In this general setting, we show how under a natural condition on the distribution of the lifetimes, the probability signature of the system can be expressed in terms of the probability signatures of the modules. We finally discuss a few situations where this condition holds in the non-i.i.d. and nonexchangeable cases and provide some applications of the main results

When solid recovered fuel (SRF) production and consumption maximize environmental benefits? A life cycle assessment

Solid recovered fuel (SRF) from non-recyclable waste obtained from source separation and mechanical treatments can replace carbon coke in cement plants, contributing to the carbon neutrality. A life cycle assessment (LCA) of the SRF production from non-recyclable and selected waste was conducted in an Italian mechanical treatment plant to estimate the potential environmental impacts per ton of SRF produced. The analysis would contribute to evaluate the benefits that can be obtained due to coke substitution in best- and worst-case scenarios. The avoided impacts achieved were assessed, together with an evaluation of the variables that can affect the environmental benefits: SRF biogenic carbon content (in percentage of paper and cardboard); transportation distances travelled from the treatment plant to the cement kiln; the renewable energy used in the mechanical facility. On average, about 35.6 kgCO2-eq are generated by the SRF transportation and production phase. These impacts are greatly compensated by coke substitution, obtaining a net value of about 1.1 tCO2-eq avoided per ton of SRF. On balance, the global warming potential due to SRF production and consumption ranges from about 542 kgCO2-eq to about 1729 kgCO2-eq. The research recommended the use of SRF to substitute coke in cement kilns also in low densely-populated areas to mitigate environmental impacts and achieve carbon neutrality at a global level

Dynamical friction and the evolution of satellites in virialized halos: the theory of linear response

The evolution of a small satellite inside a more massive truncated isothermal spherical halo is studied using both the Theory of Linear Response for dynamical friction and N-Body simulations. The analytical approach includes the effects of the gravitational wake, of the tidal deformation and the shift of the barycenter of the primary, so unifying the local versus global interpretation of dynamical friction. Sizes, masses, orbital energies and eccentricities are chosen as expected in hierarchical clustering models. We find that in general the drag force in self-gravitating backgrounds is weaker than in uniform media and that the orbital decay is not accompanied by a significant circularization. We also show that the dynamical friction time scale is weakly dependent on the initial circularity. We provide a fitting formula for the decay time that includes the effect of mass and angular momentum loss. Live satellites with dense cores can survive disruption up to an Hubble time within the primary, notwithstanding the initial choice of orbital parameters. Dwarf spheroidal satellites of the Milky Way, like Sagittarius A and Fornax, have already suffered mass stripping and, with their present masses, the sinking times exceed 10 Gyr even if they are on very eccentric orbits.Comment: 27 pages including 9 figures. Accepted for publication in the Astrophysical Journal. Part 2, issue November 10 1999, Volume 52

A especificação de um middleware para dispositivos móveis utilizando grades de computadores

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Ciência da Computação.Grades de computadores (grids) têm como característica principal prover uma distribuição de processamento e fornecer integração entre os dispositivos da grade. A computação móvel tem por objetivo o fornecimento de serviços móveis, isto é, entrega de informação a qualquer hora e em qualquer lugar, através de dispositivos móveis. Baseado neste contexto, esta dissertação motivada pela capacidade das grades de computadores de homogeneização de dispositivos e alto poder de processamento apresenta uma arquitetura para integrar os serviços da computação móvel às características da computação em grade através de um middleware. Este middleware é responsável pela transparência de acesso aos recursos, dispositivos móveis e não móveis, por parte dos usuários. Com isto pretende-se resolver alguns problemas relacionados a computação móvel, como falta de poder de processamento, baixa capacidade de memória entre outros descritos ao longo da dissertação pelo uso de grades de computadores. Esta dissertação contribui com uma nova abordagem para a resolução de problemas móveis ao integrar computação em grade com computação móvel

Laboratory chemical waste: hazard classification by GHS and transport risk

OBJETIVOS: Identificar e avaliar, com base no Sistema Globalmente Harmonizado de Classificação e Rotulagem de Produtos Químicos (GHS) e na legislação da Agência Nacional de Transportes Terrestres (ANTT), os perigos provenientes dos resíduos químicos gerados em laboratórios de pesquisa na área de saúde. MÉTODOS: Resíduos químicos gerados em dois Laboratórios de Investigação Médica da Faculdade de Medicina da Universidade de São Paulo foram inventariados, no período de novembro de 2017 a abril de 2019, e classificados conforme o GHS (frases de perigo) e a legislação de transportes da ANTT (classes de risco), para determinação dos perigos provenientes das respectivas substâncias e misturas. RESULTADOS: No total, foram identificadas 40 substâncias ou misturas, cuja classificação pelo GHS indicou 36 frases de perigo, sendo 27 relacionadas à saúde humana. De acordo com a legislação estabelecida pela ANTT, foram encontrados 16 casos de periculosidade associada à inflamabilidade, 15 casos relacionados à toxicidade e 12 casos relativos à corrosividade. CONCLUSÕES: Resíduos químicos gerados nos laboratórios estudados são diversificados quanto a suas características de periculosidade, implicando a possibilidade de exposição a riscos severos aos trabalhadores, aos estudantes e ao ambiente. A correta identificação desses resíduos é fator primordial para diminuição da exposição aos riscos.OBJECTIVES: To identify and evaluate, based on the Globally Harmonized System of Classification and Labelling of Chemicals (GHS) and the legislation of the Agência Nacional de Transportes Terrestres (ANTT – National Agency for Terrestrial Transport), the hazards arising from chemical waste generated in research laboratories in the health area. METHODS: Chemical residues generated in two medical research laboratories of the Faculdade de Medicina da Universidade de São Paulo were inventoried, from November 2017 to April 2019, and classified according to the GHS (hazard statements) and the ANTT transport legislation (risk classes), to determine the dangers coming from the respective substances and mixtures. RESULTS: In total, we identified 40 substances or mixtures with classification by the GHS indicating 36 hazard statements, 27 of which related to human health. According to the legislation established by ANTT, we found 16 cases of hazard associated with flammability, 15 cases related to toxicity and 12 cases related to corrosivity. CONCLUSIONS: Chemical residues generated in the laboratories studied are diversified in terms of their hazard characteristics, implying the possibility of exposure to severe risks to workers, students and the environment. The correct identification of these residues is a primary factor for reducing exposure to risks

Aproximaciones al sistema judicial 1823-1830: Continuidades y rupturas

Con el presente trabajo se pretende un acercamiento al sistema judicial de 1823 a 1830 en la naciente República. Es importante resaltar que tal época reviste un interés particular, pues las instituciones propias de la República se encontraban atadas a dos grandes formas de entender y desarrollar el proceso independentista: continuidad o ruptura, son las categorías sobre las cuales se articulan los ejes de los agitados movimientos políticos en el escenario de la República de Colombia para 1821. Esta época se vio surcada por el mantenimiento soterrado o descubierto de procedimientos propios de la colonia para el manejo del Estado, lo que constituye un punto de quiebre, amparado en las posibilidades de organización política que brindaba la independencia, fundados en criterios liberales para lograr tales propósitos

Thermo-mechanical Investigation of Novel GFRP-glass Sandwich Facade Components

Modern building envelopes are typically high-technological systems that need to meet strict requirements regarding architectural intent, structural capacity, energy-efficiency and durability. The study presented in this paper is based on recent research performed at the Glass & Façade Technology Research Group (University of Cambridge) that investigates high-performance engineered unitised systems as an alternative to traditional curtain-walls for building facades. The proposed unitised systems has a sandwich design made of two outer glass face sheets separated by, and bonded to, glass fibre-reinforced polymer (GFRP) pultruded profiles. This arrangement results in a lightweight and slim structure that could potentially provide high structural and thermal performances. Results discussed in this paper constitute a preliminary outcome of an extended investigation aimed to assess and compare, by means of Finite Element (FE) numerical simulations, the thermal and structural performances of novel frame-integrated (GFRP-glass) sandwich systems and traditional non-integrated frame curtain wall systems. The reported FE results, as shown, give evidence of the potential of the novel design concept, with improved thermal and structural performances compared to traditional non-integrated systems (up to +10% and +15%, respectively)

Spain intra-industry trade in Latin America a bilateral analysis 2011 - 2021

26 p.The analysis and impact of international trade have been taking on great importance as a factor of macroeconomic prosperity; in the same way, the pattern of trade impacts the competitiveness of the country's industries. In this sense, the simultaneous exports and imports of the same sector that determine intra-industrial trade impact on the sectoral competitiveness trough the generation of international trade of industries and products belonging to the same statistical category; then not based on the comparative advantages of international trade; but on the competitive advantages derived from the differentiation of products and added value. Under this focus, the study of intra-industry trade between Spain and Latin America during the period 2011-2021 is the basic objective of this working paperEl análisis e impacto del comercio internacional ha ido tomando gran importancia como factor de prosperidad macroeconómica; de la misma manera que el patrón de comercio impacta la competitividad de las industrias de un país. En este sentido, las exportaciones e importaciones simultáneas de un mismo sector que determinan el comercio intraindustrial impactan en la competitividad sectorial al generar comercio internacional de sectores y productos pertenecientes a la misma categoría estadística; es decir, no basados en las ventajas comparativas del comercio internacional; sino en las ventajas competitivas derivadas de la diferenciación de productos y el valor añadido. Bajo este enfoque, el propósito básico de este documento de trabajo es el estudio del comercio intraindustrial entre España y Latinoamérica en el período 2011-2021