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The purpose of this research is to establish a robust numerical framework for the calibration of macroscopic constitutive parameters, based on the analysis of polycrystalline RVEs with computational homogenisation.

This framework is composed of four building-blocks: (1) the multi-scale model, consisting of polycrystalline RVEs, where the grains are modelled with anisotropic crystal plasticity, and computational homogenisation to link the scales, (2) a set of loading cases to generate the reference responses, (3) the von Mises elasto-plastic model to be calibrated, and (4) the optimisation algorithms to solve the inverse identification problem. Several optimisation algorithms are assessed through a reference identification problem. Thereafter, different calibration strategies are tested. The accuracy of the calibrated models is evaluated by comparing their results against an FE2 model and experimental data.

In the initial tests, the LIPO optimiser performs the best. Good results accuracy is obtained with the calibrated constitutive models. The computing time needed by the FE2 simulations is 5 orders of magnitude larger, compared to the standard macroscopic simulations, demonstrating how this framework is suitable to obtain efficient micro-mechanics-informed constitutive models.

This contribution proposes a numerical framework, based on FE2 and macro-scale single element simulations, where the calibration of constitutive laws is informed by multi-scale analysis. The most efficient combination of optimisation algorithm and definition of the objective function is studied, and the robustness of the proposed approach is demonstrated by validation with both numerical and experimental data.

The purpose of this paper is to predict the yield locus of porous ductile materials, evaluate the impact of void geometry and compare the computational results with existing analytical models.

A computational homogenization strategy for the definition of the elasto-plastic transition is proposed. Representative volume elements (RVEs) containing single-centred ellipsoidal voids are analysed using three-dimensional finite element models under the geometrically non-linear hypothesis of finite strains. Yield curves are obtained by means of systematic analysis of RVEs considering different kinematical models: linear boundary displacements (upper bound), boundary displacement fluctuation periodicity and uniform boundary traction (lower bound).

The influence of void geometry is captured and the reduction in the material strength is observed. Analytical models usually overestimate the impact of void geometry on the yield locus.

This paper proposes an alternative criterion for porous ductile materials and assesses the accuracy of analytical models through the simulation of three-dimensional finite element models under geometrically non-linear hypothesis.

This research sheds light on the distinct decision-making behaviors and perceptions related to the value attributed to money, uncovering nuances in the interrelationship between money valuation and its ensuing influence on risk perceptions and related behaviors, mainly focusing on financial education.

Executed in the Brazilian market, this study employs a quantitative approach, encompassing 663 participants and deploying comprehensive statistical methodologies – principally, structural equation modeling based on variances – to scrutinize the amassed primary data.

The insights from the study reveal a significant impact of both negative money value (NMV) and positive money value (PMV) on participants' financial decisions, profoundly shaping perceptions, acceptances and responses to risk. Consequently, this study underscores the pivotal role the perceived value of money plays in sculpting financial behaviors and formulating risk management strategies. Distinctly, this research emphasizes intrinsic monetary values, extending unprecedented insights by delineating aversive behaviors toward losses and risks and probing the repercussions of both negative and positive monetary values.

It acts as an avant-garde exploration, unveiling new perspectives on upcoming consumers' anticipated financial decision-making approaches and pinpointing areas warranting deeper exploration and comprehension within the fluid consumer market landscape.

Esta investigación arroja luz sobre los distintos comportamientos y percepciones en la toma de decisiones relacionadas con el valor atribuido al dinero, descubriendo matices en la interrelación entre la valoración del dinero y su influencia subsiguiente en las percepciones de riesgo y comportamientos relacionados, centrándose principalmente en la educación financiera.

Ejecutado en el mercado brasileño, este estudio emplea un enfoque cuantitativo, abarcando a 663 participantes y desplegando metodologías estadísticas integrales, principalmente el Modelado de Ecuaciones Estructurales basado en varianzas, para escrutar los datos primarios acumulados.

Las percepciones obtenidas en el estudio revelan un impacto significativo tanto de los Valores Negativos como de los Valores Positivos del Dinero en las decisiones financieras de los participantes, moldeando profundamente percepciones, aceptaciones y respuestas al riesgo. En consecuencia, este estudio subraya el papel fundamental que desempeña el valor percibido del dinero en la formación de comportamientos financieros y en la formulación de estrategias de gestión de riesgos. De manera distintiva, esta investigación enfatiza los valores monetarios intrínsecos, ampliando perspectivas sin precedentes al delinear comportamientos aversivos hacia pérdidas y riesgos y explorar las repercusiones de los valores monetarios negativos y positivos.

Actúa como una exploración vanguardista, desvelando nuevas perspectivas sobre los enfoques de toma de decisiones financieras anticipadas por parte de los consumidores emergentes y señalando áreas que requieren una exploración y comprensión más profundas dentro del dinámico panorama del mercado de consumidores.

The repercussions of Portugal's colonialism are not widely discussed. The marks of colonialism in the public space are still present in the urban landscape of Portuguese cities. Despite the growing activity of the Black movement's in the country, they are still not being systematically considered in the design of public policies. Moreover, the Portuguese census does not include any data collection on ethnic belonging. Therefore, it is difficult to deepen the knowledge of the Black communities. The Black community has been growing in Porto, the second-largest city in Portugal and it remains highly invisible. Starting from a collaborative project between Portuguese and American professionals, acting in the fields of sociology and socially engaged curatorial and contemporary art practices, an experimental approach was developed to map and cocreate with the Black community in Porto. By using digital tools while collecting, analyzing, and sharing data, and by applying an ethnographic approach and techniques of exploration from documentary photography, the team developed a collaborative project side by side with the community. An exchange between disciplinary knowledge and “various subject positions,” with all participants engaging in an exploration of how to begin decolonizing the city through those tools took place at the project TRAVESSIA. This chapter explores how the Black nonelite is expressing and questioning race and ethnic inequalities in Porto by discussing the results of this collaborative project.

This study aims to propose and numerically assess different ways of discretising a very weak formulation of the Poisson problem.

We use integration by parts twice to shift smoothness requirements to the test functions, thereby allowing low-regularity data and solutions.

Various conforming discretisations are presented and tested, with numerical results indicating good accuracy and stability in different types of problems.

This is one of the first articles to propose and test concrete discretisations for very weak variational formulations in primal form. The numerical results, which include a problem based on real MRI data, indicate the potential of very weak finite element methods for tackling problems with low regularity.

Due to the mixed evidence regarding politically connected (PCON) firms and voluntary disclosure, the authors seek to investigate the direction of the association between Brazilian PCON firms and their level of information disclosed in the fight against corruption. This study is conducted in a developing country with a weak judicial system where board members or directors with political connections can operate without any oversights.

The authors empirically test our hypothesis that voluntary anti-corruption disclosure is negatively associated with political connections. Content analysis, Wilcoxon Rank and Pearson Correlation were employed in a sample of 30 companies that belong to sectors with the highest risk of corruption, between 2014 and 2016, the period of Brazilian elections. A sample of 90 observations is used with data collected from annual reports of companies listed on the São Paulo Stock Exchange in Brazil.

The study’s results indicate a positive and significant association between the level of voluntary anti-corruption disclosure and corporate political connection, confirming our second hypothesis. PCON firms could seek to improve their legitimacy after recent corporate corruption scandals discovered in Brazil where government members participated in the schemes of bribe and money laundering and embezzlement. Although our sample is composed of firms in industries of high corruption risk, which could increase bias, the results improve the literature with empirical contribution that has given little attention to the issue.

The latest corruption scandals in Brazil showed that companies were involved with government officials, corruption is one of the country's biggest issues for diverting public resources to basic needs such as education and health. The relationship between political connections and voluntary disclosure is an open empirical question, particularly dealing with anti-corruption. The study’s findings bring light on the subject, which deserves greater attention not only from researchers but from the society that is most affected by corruption.

Develop biodegradable meshes as a novel solution to address issues associated with using synthetic meshes for POP repair.

Computational models were created with variations in the pore geometry, pore size, filament thickness, and inclusion of filaments around specific mesh regions. Subsequently, one of the meshes was 3D printed to validate the results obtained from the simulations. Following this, a uniaxial tensile test was carried out on the vaginal tissue of a sow to compare with the simulations, to identify meshes that displayed behaviour akin to vaginal tissue. Finally, the most promising outcomes were compared with those of the uterosacral ligament and a commercially available mesh.

Following a comprehensive analysis of the results, the mesh that most accurately replicates the behaviour of the vaginal tissue showcases a smaller pore diameter (1.50 mm), filaments in specific areas of the mesh, and variable filament thickness across the mesh. Nevertheless, upon comparing the outcomes with those of the uterosacral, the meshes do not exhibit similar behaviour to the ligament. Finally, the commercially available mesh does not represent the behaviour of both the vaginal tissue and the uterosacral ligament and in this sense may not be the best treatment option for POP repair.

Their biocompatibility and biomechanical properties make them a potential solution to the disadvantages of synthetic meshes. Personalized/customized meshes could be part of the future of surgical POP repair.

Adaptive load-bearing structures pursue the approach of saving mass within a load-bearing structure by adding external energy, thus saving materials and resources. This paper provides an overview of current research developments and shows some examples of existing prototypes.

First, basic terms and definitions from the research field of adaptive structures are introduced. After a brief historical insight, the numerical methods and prototypes used are presented as examples. The paper concludes with a summary of the state-of-the-art and open questions.

The current state of the art shows that the idea of adaptive structures offers great potential for more sustainability and resource efficiency in the construction industry. However, it also shows that research is still at the basic stage and that there are still some gaps in research.

The implementation of adaptive load-bearing structures is just one of many different approaches to greater sustainability in the construction sector. The issue of adaptive structures is a highly interdisciplinary field of research. The following paper is a literature review intended to summarize and critically evaluate the state-of-the-art research in this field. In the final section, some open questions are addressed, indicating that this research topic is still evolving.

During a fall, a significant part of the major forces is absorbed by the dorsolumbar column area. When the applied stresses exceed the yield strength of the bone tissue, fractures can occur in the vertebrae. Vertebral fractures constitute one of the leading causes of trauma-related hospitalizations, accounting for 15% of all admissions. Posterior pedicle screw fixation has become a common method for treating burst fractures. However, physicians remain divided on the number of fixed segments that are needed to improve clinical outcomes. The present work aims to understand the biomechanical impact of different fixation methods, improving surgical treatments.

A finite element model of the dorsolumbar spine (T11–L3) section, including cartilages, discs and ligaments, was created. The dorsolumbar stability was tested by comparing two different surgical orthopedic treatments for a fractured first lumbar vertebra on the L1 vertebra: the posterior short segment fixation with intermediate screws (PSS) and the posterior long segment fixation (PL). Distinct loads were applied to represent daily activities.

Results show that both procedures provide acceptable segment fixation, with the PL offering less freedom of movement, making it more stable than the PSS. The PL approach can be the best choice for an unstable fracture as it leads to a stiffer spine segment.

This study introduces a novel computational model designed for the biomechanical analysis of dorsolumbar injuries, aiming to identify the optimal treatment approaches within both clinical and surgical contexts.