Structural behaviour analysis of Faria Guimarães station

No presente estudo efectua-se a modelação e análise do comportamento estrutural da estação Faria Guimarães, do Metro do Porto. A estação é constituída por um cruzamento oblíquo de duas grandes galerias executadas através do método SEM/NATM. A obra é de elevada complexidade devido aos condicionamentos geométricos da estação e obras adjacentes, à grande heterogeneidade do maciço e à ocupação intensa da superfície. A análise do comportamento estrutural da estação foi realizada recorrendo a modelos numéricos 2D e 3D, bem como a resultados obtidos com a observação da estação.In present paper the modelling and structural behaviour analysis of the Faria Guimarães station, of Metro do Porto, is presented. The station includes the inclined intersection of two large galleries executed through SEM/NATM method. The work is highly complex due to geometric limitations of the station and adjacent works, the heterogeneity of the rock mass and the dense occupation at surface. The structural behaviour analysis of the station was performed using 2D and 3D numerical models, as well as results obtained through the observation of the station.Fundação para a Ciência e Tecnologia (FCT) - Projecto POCI/ECM/57495/2004, intitulado Geotechnical Risk in Tunnels for High Speed Trains

Tensor-Based Methods for Blind Spatial Signature Estimation in Multidimensional Sensor Arrays

The estimation of spatial signatures and spatial frequencies is crucial for several practical applications such as radar, sonar, and wireless communications. In this paper, we propose two generalized iterative estimation algorithms to the case in which a multidimensional (R-D) sensor array is used at the receiver. The first tensor-based algorithm is an R-D blind spatial signature estimator that operates in scenarios where the source’s covariance matrix is nondiagonal and unknown. The second tensor-based algorithm is formulated for the case in which the sources are uncorrelated and exploits the dual-symmetry of the covariance tensor. Additionally, a new tensor-based formulation is proposed for an L-shaped array configuration. Simulation results show that our proposed schemes outperform the state-of-the-art matrix-based and tensor-based techniques

Distance Functions and Normalization Under Stream Scenarios

Data normalization is an essential task when modeling a classification system. When dealing with data streams, data normalization becomes especially challenging since we may not know in advance the properties of the features, such as their minimum/maximum values, and these properties may change over time. We compare the accuracies generated by eight well-known distance functions in data streams without normalization, normalized considering the statistics of the first batch of data received, and considering the previous batch received. We argue that experimental protocols for streams that consider the full stream as normalized are unrealistic and can lead to biased and poor results. Our results indicate that using the original data stream without applying normalization, and the Canberra distance, can be a good combination when no information about the data stream is known beforehand.Comment: Paper accepted to the 2023 International Joint Conference on Neural Network

Local Power as the Basis of the Understanding of the Federative Pact

The research aimed to describe the existing problems in the relationship between City, State and Federal Government, through the Brazilian Federative Pact, mainly for municipalities with population of less than 50,000 inhabitants. The research is structured from a qualitative perspective. The theoretical framework was built from the local power of the discussion based on the understanding of the federal pact and local interest and the municipality in Brazil. The paper argues that the federal pact is little debated, discussed, much less questioned by society in general, it only strengthens the lack of a legal and institutional framework for coordination and cooperation among federal entities in the country, which results in public policy fragmented the territory and without direction, causing waste of public resources

Factor Analysis and the Social Capital Index: A Study at the Brazil / Bolivia Border

Objective: The study aimed to build the level of social capital by neighborhoods Guajará-Mirim border region between the State of Rondônia, Brazil and the Republic of Bolivia, which in recent years has been showing signs of social fragility due advance not virtuous practices. Method: This work made use of research in secondary bases as well as in primary bases. The tabulation of qualitative and quantitative data was performed in Excel (2010) and for their processing performance index construction purposes were calculated following the factorial analysis techniques presented by Hair et al. [19] Santana [20, 21]; and Choi [22]. For this, we made use of the statistical tool SPSS (Statistical Package for Social Sciences) for the construction of the indices of social capital. The correlation analysis process was done in Excel. results: It was observed that the capital reached regular levels in Guajará-Mirim neighborhoods not observable, so correlations between the studied parameters, however, it needs to be further studied as factors such as the flooding of the Mamore river may have interfered in any way in the implementation process of the field survey to the residents of the city. It became clear that the municipality of Guajará-Mirim suffers from serious social problems and that most problems are correlated with the increase in alcoholic beverage market in the city and use drugs. However, was not observed as the institutional arrangements are dealing with this problem, that is, as public bodies are relating to discuss actions for concrete solutions to this evil that plagues large portion of the population of Guajará-Mirim, mainly young teenagers residents of Guajá-Mamim. However, we hope to continue this work in order to better understand this mechanism of social network between the actors of this process in the region

Desempenho reprodutivo de bovinos na sub-região dos Paiaguás do Pantanal Mato-grossense. I. Efeito da suplementação mineral e da idade de desmama sobre a idade e o peso ao primeiro parto

The effects of mineral supplementation (common salt = CS, CS + dicalcium phosphate = SP and SP + micronutrients) and of weaning age (six, eight and ten months) on the age and weight at first calving of Zebu heifers were studied in the Paiaguás sub-region of the Pantanal Mato-grossense, Brazil. A completely randomized design was used. The experiment was conducted from February 1980 to November 1984. Age and weight as first calving were not influenced (P>0.05) by weaning age. Also mineral supplementation did not affect the age at first calving, but influenced weight at calving, which was about 30 kg higher (P0,05) pela idade à desmama dos animais. A suplementação mineral também não afetou a idade ao primeiro parto, mas influenciou os pesos à primeira cria, que foram aproximadamente 30 kg mais altos (P<0,01) nas novilhas suplementadas com fósforo, que naquelas que receberam somente sal comum. Concluiu-se que é viável a antecipação da desmama no Pantanal e da mesma forma, a suplementação com fósforo

Unpredictability in seasonal infectious diseases spread

In this work, we study the unpredictability of seasonal infectious diseases considering a SEIRS model with seasonal forcing. To investigate the dynamical behaviour, we compute bifurcation diagrams type hysteresis and their respective Lyapunov exponents. Our results from bifurcations and the largest Lyapunov exponent show bistable dynamics for all the parameters of the model. Choosing the inverse of latent period as control parameter, over 70% of the interval comprises the coexistence of periodic and chaotic attractors, bistable dynamics. Despite the competition between these attractors, the chaotic ones are preferred. The bistability occurs in two wide regions. One of these regions is limited by periodic attractors, while periodic and chaotic attractors bound the other. As the boundary of the second bistable region is composed of periodic and chaotic attractors, it is possible to interpret these critical points as tipping points. In other words, depending on the latent period, a periodic attractor (predictability) can evolve to a chaotic attractor (unpredictability). Therefore, we show that unpredictability is associated with bistable dynamics preferably chaotic, and, furthermore, there is a tipping point associated with unpredictable dynamics

Lyra2: Efficient Password Hashing with High Security against Time-Memory Trade-Offs

We present Lyra2, a password hashing scheme (PHS) based on cryptographic sponges. Lyra2 was designed to be strictly sequential (i.e., not easily parallelizable), providing strong security even against attackers that uses multiple processing cores (e.g., custom hardware or a powerful GPU). At the same time, it is very simple to implement in software and allows legitimate users to fine tune its memory and processing costs according to the desired level of security against brute force password-guessing. Lyra2 is an improvement of the recently proposed Lyra algorithm, providing an even higher security level against different attack venues and overcoming some limitations of this and other existing schemes

Lyra: Password-Based Key Derivation with Tunable Memory and Processing Costs

We present Lyra, a password-based key derivation scheme based on cryptographic sponges. Lyra was designed to be strictly sequential (i.e., not easily parallelizable), providing strong security even against attackers that use multiple processing cores (e.g., custom hardware or a powerful GPU). At the same time, it is very simple to implement in software and allows legitimate users to fine-tune its memory and processing costs according to the desired level of security against brute force password guessing. We compare Lyra with similar-purpose state-of-the-art solutions, showing how our proposal provides a higher security level and overcomes limitations of existing schemes. Specfically, we show that if we fix Lyra\u27s total processing time t in a legitimate platform, the cost of a memory-free attack against the algorithm is exponential, while the best known result in the literature (namely, against the scrypt algorithm) is quadratic. In addition, for an identical same processing time, Lyra allows for a higher memory usage than its counterparts, further increasing the cost of brute force attacks

The influence of the weaning age on the growth of heifers in the cowlands of Mato Grosso state

O estudo foi realizado no Pantanal Mato-grossense, com o objetivo de determinar a influência da idade de desmama no desenvolvimento de bezerras na fase de recria, em regime de pasto nativo. Foram utilizadas 88 unidades experimentais divididas em três ensaios experimentais com suplementações minerais diferentes. Cada ensaio foi composto por três tratamentos (seis, oito e dez meses de idade de desmama) num arranjo inteiramente casualizado. Não foram determinadas diferenças significativas nos três ensaios experimentais, entre os tratamentos (idades de desmama) no que se refere aos pesos médios alcançados aos 18 meses de idade. E possível concluir ser viável a desmama aos seis meses de idade em campos nativos, a partir da metade do período das cheias quando houver razoável quantidade e qualidade de pastagem associada a prática de everminação pós-desmama. Como não houve diferenças significativas nos pesos médios aos 18 e 24 meses de idade, é possível supor não existir influência da idade de desmama na idade à primeira cria.This work was carried out in order to determine the influence of the weaning age on the growth of heifers during growing period, when in native pasture. Eighty eight experimental units were divided into three experiments, each one with different mineral supplementations. Each trial was compounded by three treatments (six, eight and ten months old at weaning) in a completely randomized design. Statistical analysis showed no difference among treatments (age of weaning) in terms of weight gain at 18 months of age. It was concluded the viability of weaning at six months old in native pasture from the mid-period of inundation in presence of good amount and quality of pasture and associated a deworming programme. Since there was no statistical difference between 18 and 24 months of age, it is expected no influence of weaning at age on the first mating