The use of robots in the construction industry

This article first explains why it is currently not feasible to use robots on construction sites. The authors argue that robotics will be utilized in the upstream industries, either in component manufacture or in constructive processes capable of being undertaken in a traditional factory setting. Although the former would be a simple way of incorporating robotics into the construction industry, the second would have major implications for the constructive process that extends from the project design phase to the technologies employed on the building site

The 7-items version of the connectedness to nature scale: A study of its validity and reliability with Brazilians

Human actions are largely responsible for environmental problems such as climate change, deforestation, and biodiversity loss (Steffen et al. 2015). Hence, several authors have highlighted the importance of a better understanding of the drivers of pro-environmental behaviors (PEB) (Collado et al. 2015; Whitburn et al. 2019). Connectedness to nature (CN) has been defined as a latent construct that represents the connection between individuals and nature and is related to individuals’ emotions, beliefs and behaviors toward nature (Mayer and Frantz 2004; Tam 2013; Pasca et al. 2017; Whitburn et al. 2019). CN is thought to be one of the main factors leading to PEB (Tam 2013; Frantz and Mayer 2014; Gkargkavouzi et al. 2018) and, as such, there is a growing interest on the factors leading to CN (Di Fabio and Kenny 2018; Rosa and Collado 2019). For example, experiences in nature (e.g., nature-based recreation) are seen as a relevant determinant of CN (Duron-Ramos et al. 2020; Rosa and Collado 2019)..

Fire resistance tests on concrete columns

The reinforced concrete elements are known to have enhanced fire behaviour however there are many things that can affect that performance. In the last years there have been carried out, in the University of Coimbra, Portugal, dozens of fire resistance tests on concrete columns where it was tested the influence of various parameters on the behaviour of these columns. Several parameters that might have influence on the behaviour of concrete columns in fire, were tested: cross section shape (round and square), longitudinal reinforcement ratio, slenderness of the column, stiffness of the surrounding structure (restraint level), load level and the load eccentricity. The restraining level to the thermal elongation of the columns showed not being a relevant parameter in their fire resistance probably due the increase in rotational restrain associated with the increase in the axial restraint. The first increases the fire resistance while the second reduces. The increasing of the load level lead to a reduction, while the increasing of the longitudinal reinforcement ratio or the decreasing of the slenderness of the columns lead to an increasing of the fire resistance. The spalling was also an aspect analysed in these tests. The higher load levels, the shape of the cross-section, the type of concrete with or without steel and / or polypropylene fibres, and the steel reinforcement ration was parameters that showed to have influence on concrete cracking and spalling

Avaliação do risco de incêndio de uma habitação multifamiliar pelo método de FRIM

Os conceitos de qualidade de vida e de qualidade de ambiente urbano estão intimamente ligados ao conceito de requalificação do espaço urbano. Nos centros urbanos, a segurança contra incêndio é um tema ao qual se deve dar grande relevância, não só pelo risco que pode representar para a perda de vidas humanas, mas também pelo risco que representa à riqueza cultural, patrimonial e valor histórico. O presente trabalho tem como objetivo a análise do risco de incêndio da reabilitação de um edifício urbano com base no Regime Jurídico e Regulamento Técnico de Segurança Contra Incêndio em Edifícios. Para a análise do risco de incêndio do projeto em estudo, aplicou-se a metodologia Fire Rysk Index Method (FRIM).info:eu-repo/semantics/publishedVersio

Prediction of lamb body composition using in vivo bioimpedance analysis

The objective of this study was to evaluate the potential of in vivo bioimpedance analysis (BIA) as a method to estimate body composition in lambs. Thirty-one Texel x Ile de France crossbreed ram lambs were slaughtered at pre-determined intervals of average weights of 20, 26, 32, and 38 kg. Before the slaughter of the animals, their body weight (BW) and body length (BL) were measured. The values for resistance (Rs) and reactance (Xc) were collected using a single-frequency BIA equipment (Model RJL Quantum II Bioelectrical Body Composition Analyzer). The BIA main variables such as body bioelectrical volume (V), phase angle (PA), resistive density (RsD), and reactive density (XcD) were then calculated. The soft tissue mass of the right-half cold carcass was analyzed in order to determine its chemical composition. Multiple regression analyses were performed using the lamb body composition as dependent variables and the measurements related to bioimpedance as independent variables. The best regression models were evaluated by cross-validation. The predictive model of moisture mass, which was developed by using XcD and V, accounted for 84% of its variation. Resulting models of percentage moisture (R2 = 0.79), percentage lean mass (R2 = 0.79), percentage fat (R2 = 0.79), and fat mass (R2 = 0.87) were obtained using RsD and V. Furthermore, the values of RsD regarding V, and PA in the prediction models accounted for 91% and 89% of variation in protein mass and lean mass, respectively. Bioimpedance analysis proved to be an efficient method to estimate the body composition of lambs slaughtered at different body mass stages

On the magnetism of Ln{2/3}Cu{3}Ti{4}O{12} (Ln = lanthanide)

The magnetic and thermodynamic properties of the complete Ln$_{2/3}$Cu$_3$Ti$_4$O$_{12}$ series were investigated. Here $Ln$ stands for the lanthanides La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb. %Most of the compounds were prepared as single phase polycrystalline powder %without any traces of impurities. Marginal amounts of %impurities $(< 2$ were detected $Ln=$ Gd, Er, and Tm. %Significant amounts of impurity phases were found for $Ln=$ Ce and Yb. All the samples investigated crystallize in the space group $Im\bar{3}$ with lattice constants that follow the lanthanide contraction. The lattice constant of the Ce compound reveals the presence of Ce$^{4+}$ leading to the composition Ce$_{1/2}$Cu$_3$Ti$_4$O$_{12}$. From magnetic susceptibility and electron-spin resonance experiments it can be concluded that the copper ions always carry a spin $S=1/2$ and order antiferromagnetically close to 25\,K. The Curie-Weiss temperatures can approximately be calculated assuming a two-sublattice model corresponding to the copper and lanthanide ions, respectively. It seems that the magnetic moments of the heavy rare earths are weakly coupled to the copper spins, while for the light lanthanides no such coupling was found. The $4f$ moments remain paramagnetic down to the lowest temperatures, with the exception of the Tm compound, which indicates enhanced Van-Vleck magnetism due to a non-magnetic singlet ground state of the crystal-field split $4f$ manifold. From specific-heat measurements we accurately determined the antiferromagnetic ordering temperature and obtained information on the crystal-field states of the rare-earth ions. The heat-capacity results also revealed the presence of a small fraction of Ce$^{3+}$ in a magnetic $4f^1$ state.Comment: 10 pages, 10 figure

Electrooxidation of C-4 polyols on platinum single- crystals: a computational and electrochemical study

Many polyols are abundant and cheap molecules highly spread in the biomass. These molecules have an enormous potential to be used in electrochemical devices to generate energy and/or value-added molecules. The electrooxidation of polyols can produce different substances of interest in the chemical industry concomitantly to high purity hydrogen in electrolyzers. The cost in the production of all these chemicals depends, among other factors, on the develop of more active and selective catalysts. However, in order to search for these materials using computational experiments, it is mandatory to have a better understanding of the fundamental aspect of the reactions, which permit to base the search on the adsorption energies of one or more key reaction intermediates. To contribute to this task, we performed (spectro)-electrochemical and computational experiments to study the electrooxidation of C-4 polyols. We show that the electrooxidation of polyols does not depend on the relative orientation of their OH groups. Besides, using Pt single crystals, we demonstrate that the trend for the oxidation of the primary carbon (relative to the secondary) increases in the order Pt(111) < Pt(100) < Pt(110) and that this result can be extended to polyols with longer carbon chains. Finally, computational experiments permit us to rationalize these trends looking at the relative stability of double dehydrogenated intermediates on the Pt basal planes.Catalysis and Surface Chemistr