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Abstract: Optimization is a branch of applied mathematics which is used extensively in almost all areas of decision-making. In particular, classical method is a kind of the optimization methods that can be applied to make decisions. The optimization method can only make a better decision if the algorithm starts with an appropriate initial data. The main purpose of this study is two-folds. First, the material parameters of multivariable plasticity models, such as Mohr-Coulomb and DiMaggio-Sandler are calibrated via the gradient based optimization method by considering the appropriate initial data from porous rock database. Moreover, the calibration of models is done by the methods presented in the Nlopt library with considering the same objective functions and the same initial guess for each parameter. Then, a home-made finite element simulator is used to evaluate the correctness of the proposed material parameters identification framework. The results show the capability of the proposed optimization framework to determine properly the material parameters of multivariable plasticity models

Abstract: Wood and other bio-based building materials are often perceived as a good choice from a climate mitigation perspective. This article compares the life cycle assessment of the same multi-residential building from the perspective of 16 countries participating in the international project Annex 72 of the International Energy Agency to determine the effects of different datasets and methods of accounting for biogenic carbon in wood construction. Three assessment methods are herein considered: two recognized in the standards (the so-called 0/0 method and –1/+1 method) and a variation of the latter (–1/+1* method) used in Australia, Canada, France, and New Zealand. The 0/0 method considers neither fixation in the production stage nor releases of biogenic carbon at the end of a wood product’s life. In contrast, the –1/+1 method accounts for the fixation of biogenic carbon in the production stage and its release in the end-of-life stage, irrespective of the disposal scenario (recycling, incineration orlandfill). The -1/+1 method assumes that landfills offer only a temporary sequestration of carbon. In the –1/+1* variation, landfills and recycling are considered a partly permanent sequestration of biogenic carbon and thus fewer emissions are accounted for in the end-of-life stage. We examine the variability of the calculated life cycle-based greenhouse gas emissions calculated for a case study building by each participating country, within the same assessment method and across the methods. The results vary substantially. The main reasons for deviations are whether or not landfills and recycling are considered a partly permanent sequestration of biogenic carbon and a mismatch in the biogenic carbon balance. Our findings support the need for further research and to develop practical guidelines to harmonize life cycle assessment methods of buildings with bio-based materials

Resumo: Esse relatório analisa a relação entre temperatura ambiente, consumo de energia elétrica e condições de habitabilidade nas moradias do tipo Estúdio, do Programa de Moradia Estudantil da Unicamp. Foram avaliadas variações térmicas internas e externas, padrões de consumo elétrico e autorrelatos de saúde respiratória ao longo do ano 2022. Os resultados indicaram que o consumo de energia está diretamente associado à permanência dos moradores e à temperatura interna nas casas. Assim, quando as temperaturas ultrapassam 26 °C, o consumo tende a diminuir devido à ausência dos moradores; e na faixa de entre 22 °C e 24 °C associam-se a maior permanência dos morados em casa. Essas descobertas tem novas implicações a ser consideradas nas políticas de energia, habitabilidade e saúde em espaços internos. Recomenda-se considerar 4,5kWh/m2 como consumo de referência para moradias habitadas; e promover espaços coletivos climatizados como medida de adaptação para o calor extremo

Abstract: Fluid-filled cracks sustain a slow guided wave (Krauklis wave or crack wave) whose resonant frequencies are widely used for interpreting long period (LP) and very long period (VLP) seismic signals at active volcanoes. Significant efforts have been made to model this process using analytical developments along an infinite crack or numerical methods on simple crack geometries. In this work, we develop an efficient hybrid numerical method for computing resonant frequencies of complex-shaped fluid-filled cracks and networks of cracks and apply it to explain the ratio of spectral peaks in the VLP signals from the Fani Maoré submarine volcano that formed in Mayotte in 2018. By coupling triangular boundary elements and the finite volume method, we successfully handle complex geometries and achieve computational efficiency by discretizing solely the crack surfaces. The resonant frequencies are directly determined through eigenvalue analysis. After proper verification, we systematically analyze the resonant frequencies of rectangular and elliptical cracks, quantifying the effect of aspect ratio and crack stiffness ratio. We then discuss theoretically the contribution of fluid viscosity and seismic radiation to energy dissipation. Finally, we obtain a crack geometry that successfully explains the characteristic ratio between the first two modes of the VLP seismic signals from the Fani Maoré submarine volcano in Mayotte. Our work not only reveals rich eigenmodes in complex-shaped cracks but also contributes to illuminating the subsurface plumbing system of active volcanoes. The developed model is readily applicable to crack wave resonances in other geological settings, such as glacier hydrology and hydrocarbon reservoirs