Stereoscopic modelling and monitoring of the roughness in concrete pavements

The detection and measurement of surface properties, such as cracks and roughness, on concrete structures have been of significant interest in recent years. Crack formation, width and propagation as well as surface roughness are important indicators of the structural integrity and condition of a concrete pavement that can determine the need for an upgrade or maintenance operation in roads and bridges. The use of non-destructive testing techniques for development of analytical and numerical processing tools that enables the efficient measurement of surface properties is the aim of this work. In the proposed framework, a stereo camera set-up is utilised to map and register surface roughness of a concrete pavement. The benefit of using a depth image to create a surface map lies in its low-cost and ability to provide depth changes at a highly-refined level with approximately 0.05 mm accuracy. Concrete samples of different roughness are used to assess the viability of such technique in enhancing inspection ability and the effectiveness of robust structural health monitoring and assessment. The focus is placed on: the acquisition of spatial and visual data and creating a 3D point cloud mesh using XYZ and RGB data; an efficient algorithm for the registration and analysis of XYZ- RGB data; and accuracy assessment of stereo cameras in detection and measurement. The investigation herein outlined capitalises on the potential for stereo cameras in developing a pipeline for data acquisition, detection and measurement of cracks and surface roughness in concrete structures.ARC DE150101703, ARC DP140100529, ARC LP14010059

Desempenho produtivo de caprinos mestiços da raça Anglo-Nubiana, no Acre.

O experimento foi conduzido na Fazenda Experimental do Centro de Pesquisa Agroflorestal do Acre - CPAF-Acre, localizada no município de Rio Branco. Foram utilizados inicialmente 20 matrizes e dois reprodutores mestiços da raça An-glo-nubiana, criados em regime semi-intensivo de exploração, tendo como base alimentar pastagens de colonião (Panicum maximum) e brizantão (Brachiaria brizan-tha). O sistema de acasalamento adotado foi o da monta natural a campo, onde o macho permanecia com as fêmeas durante todo o ano. Foram obtidos os índices de prolificidade (1,26%) natalidade (125,2 %); fertilidade ao parto (87,5%); intervalo entre partos (266,2 dias); proporção sexual (50%); mortalidade de 0-6 meses (14,63%); peso ao nascer para machos (2,81 i<g), para fêmeas (2,71 kg) e fêmeas com três partos em dois anos (7,9%). Ocorreram parições em quase todos os meses do ano (exceto setembro), com uma maior concentração no período de junho a agosto (413%). As cabras que tiveram parto duplo apresentaram um peso ao parto maior (P< 0,01), em relação àquelas com panos simples. Conclui-se que o desempenho reprodutivo do rebanho estudado foi bom, podendo, no entanto, atingir índices mais elevados, desde que se introduzam, no sistema de criação, algumas práticas de manejo reprodutivo e melhores condições nutriclonais.bitstream/item/161362/1/975.pd

Local knowledge management and innovation spillover

Tourism lifestyle entrepreneurs play an essential role in the innovation and competitiveness of tourist destinations. However, existing knowledge about the determinants of the innovation they generate is far from being fully exploited. There is still little knowledge about the innovation spillover effect, which is a determining factor for the destination's competitiveness. One of the key factors for innovation results from local knowledge management and the ability of tourism lifestyle entrepreneurs to turn this knowledge into innovation. To test the role of knowledge management in innovation and spillover, a survey was conducted on a sample of 115 tourism lifestyle entrepreneurs, with the hypotheses tested using structural equations. The results reveal that place attachment and knowledge acquisition have a direct effect on knowledge assimilation and community-centered strategy. Furthermore, it was also found that community-centered strategy and knowledge assimilation play a mediating role between place attachment and innovation capacity.info:eu-repo/semantics/publishedVersio

Homogeneous metallicities and radial velocities for Galactic globular clusters. II. New CaT metallicities for 28 distant and reddened globular clusters

Although the globular clusters in the Milky Way have been studied for a long time, a significant fraction of them lack homogeneous metallicity and radial velocity measurements. In an earlier paper we presented the first part of a project to obtain metallicities and radial velocities of Galactic globular clusters from multiobject spectroscopy of their member stars using the ESO Very Large Telescope. In this paper we add metallicities and radial velocities for a new sample of 28 globular clusters, including in particular globular clusters in the MW halo and the Galactic bulge. Together with our previous results, this study brings the number of globular clusters with homogeneous measurements to $\sim 69$ \% of those listed in the W. Harris' catalogue. As in our previous work, we have used the CaII triplet lines to derive metallicities and radial velocities. For most of the clusters in this study, this is the first analysis based on spectroscopy of individual member stars. The metallicities derived from the CaII triplet are then compared to the results of our parallel study based on spectral fitting in the optical region and the implications for different calibrations of the CaII triplet line strengths are discussed. We also comment on some interesting clusters and investigate the presence of an abundance spread in the globular clusters here. A hint of a possible intrinsic spread is found for NGC 6256, which therefore appears to be a good candidate for further study.Comment: 13 pages, 9 figures, accepted for publication in Astronomy and Astrophysic

An embedded crack model for the simulation of the complex interactions in fibre reinforced concrete

There are several benefits of introducing steel fibres in reinforced concrete. They can improve the structural ductility, reduce the permeability, and provide more resistance to cracking caused by loading and shrinkage. Steel fibres are mainly activated when they are crossed by active cracks in what is known by the bridging effect. They are mostly inactive otherwise. With the progress of damage, the fibres can be pulled out or fail, in which case the bond with the cementitious matrix is a critical factor for accurate simulations. Although existing models that are able to simulate fibres as discrete elements can achieve realistic predictions, difficulties are found in the generation of complex meshes with numerous randomly-oriented fibres, namely due to the requirement of excessive degrees of freedom and long computational times. The formulation herein proposed, embeds both discrete fibres and cracks within the finite elements, while accounting for the main features of the fibre behaviour, including the main effects such as the bond between fibre and cementitious material and snubbing. It should be highlighted that the fibre behaviour is modelled without the need for additional degrees of freedom. An advanced constitutive behaviour law is implemented that accounts for the changes depending on the inclination angle of the fibre relative to the crack and its embedment length. For fracture simulation, the model uses the Discrete Strong Discontinuous Approach (DSDA), where the jumps related to the opening of the cracks are transmitted to the parent element as a rigid body motion. Several numerical tests are used to assess the performance of the numerical technique, which include comparison with other formulations and experimental data

Fast and efficient method to evaluate the potential of eutectic solvents to dissolve lignocellulosic components

The application of eutectic solvents (ESs) in lignocellulosic biomass fractionation has been demonstrated as a promising approach to accomplish efficient and environmentally friendly biomass valorization. In general, ESs are a combination of two components, a hydrogen-bonding donor and a hydrogen-bonding acceptor, in which the melting point of the mixture is lower than that of the individual components. However, there are plenty of possible combinations to form ESs with the potential to apply in biomass processing. Therefore, the development of fast and effective screening methods to find combinations capable to dissolve the main biomass components—namely cellulose, hemicelluloses, and lignin—is highly required. An accurate and simple technique based on optical microscopy with or without polarized lenses was used in this study to quickly screen and monitor the dissolution of cellulose, xylose (a monomer of hemicelluloses), and lignin in several ESs. The dissolution of these solutes were investigated in different choline-chloride-based ESs (ChCl:UREA, ChCl:PROP, ChCl:EtGLY, ChCl:OXA, ChCl:GLY, ChCl:LAC). Small amounts of solute and solvent with temperature control were applied and the dissolution process was monitored in real time. The results obtained in this study showed that cellulose was insoluble in these ESs, while lignin and xylose were progressively dissolved.publishe

The new SWOT for a sustainable world

In today’s complex and changing business environment the concern with sustainability has gained more notoriety. However, companies still do not have a sustainable perspective, but a short-term one, where their values are constantly forgotten and this concept is no longer welcomed. This research demonstrates the need for companies to adapt and to start acting in this direction. Following a set of interviews conducted with professionals with management positions of high responsibility, findings reveal that although sustainability is on the management mind, strategies and tools need to be adapted to be at the core of the organization’s strategic formulation. To support this process, a new SWOT analysis to fit a forward-looking sustainable world is proposed. Furthermore, due to the aggregative nature of the model, it represents an essential tool for an open innovation. “SWOT i” integrates the concern with sustainability as one of its pillars, placing the values and impacts that each decision can have at the center of the strategic formulation, allowing their performance to leverage.info:eu-repo/semantics/publishedVersio

Marketing communication and creative tourism: An analysis of the local destination management organization

Delivering a positive tourism experience is an expanding concern of destinations because of the growth of the tourism industry. The emergence of creative tourism has led to a continued necessity for local destination management organizations to pursue innovative and versatile strategies. This study aims to evaluate the organizational capabilities of local destination management organizations to promote a creative tourism context and develop related activities. The conceptual model was tested using a mixed-methods approach, combining a focus group with local destination management organizations with a quantitative study using multivariate statistical analysis through structural equational modeling. The findings showed that local destination management organizations ought to prioritize organizational culture by coordinating learning and effective knowledge training to strengthen marketing communication capabilities while focusing on potentiating their resources to develop the destination by implementing a local creative tourism destination, thereby generating value for a greater creative tourism local destination where tourists play an active role.info:eu-repo/semantics/publishedVersio

Fluid flows through unsaturated porous media: An alternative simulation procedure

This article studies fluid flows through an unsaturated porous matrix, modeled under a mixture theory viewpoint, which give rise to nonlinear hyperbolic systems. An alternative procedure is employed to simulate these nonlinear nonhomogeneous hyperbolic systems of two partial differential equations representing mass and momentum conservation for the fluid (liquid) constituent of mixture. An operator splitting technique is employed so that the nonhomogeneous system is split into a time-dependent ordinary portion and a homogeneous one. This latter is simulated by employing Glimm’s scheme and an approximate Riemann solver is used for marching between two consecutive time steps. This Riemann solver conveniently approximates the solution of the associated Riemann problem by piecewise constant functions always satisfying the jump condition – giving rise to an approximation easier to implement with lower computational cost. Comparison with the standard procedure, employing the complete solution of the associated Riemann problem for implementing Glimm’s scheme, has shown good agreement