Análise das propriedades de argamassa com adição de pérolas de poliestireno expandido

TCC (graduação) - Universidade Federal de Santa Catarina. Campus Joinville. Engenharia Civil de Infraestrutura.O Poliestireno Expandido (EPS), tradicionalmente conhecido como isopor, vem sendo consumido em grande quantidade na indústria da construção civil e ocupando lugar de destaque em conjunto com outros elementos tradicionalmente empregados em todo o mundo, sendo um material reciclável e de baixo impacto ambiental, que pode ser utilizado em forma de blocos, chapas ou como material agregado dos compósitos cimentícios. O objetivo deste trabalho é analisar as propriedades físicas e mecânicas de argamassas quando é adicionado EPS em sua composição, que é formada por água, areia e cimento. Os resultados são obtidos através da confecção de corpos-de-prova prismáticos de argamassa com substituição parcial de agregado miúdo (areia) por EPS nas proporções de 0,50%, 1,00% e 1,50% em massa. Para as propriedades físicas, estudaram-se a absorção de água, o índice de vazios e a massa específica, para as propriedades mecânicas os corpos-de-prova foram rompidos à flexão e compressão. Os resultados comprovam que a utilização de EPS na matriz cimentícia da argamassa reduz significativamente o peso final do material, proporcionando uma diminuição da massa específica e aumento do índice de vazios, o que, em contrapartida, acarreta em um decréscimo da resistência mecânica.Expanded Polystyrene (EPS), traditionally known as styrofoam, has been consumed in large quantities in the construction industry and occupies a prominent place together with other elements traditionally used around the world, being a recyclable material with low environmental impact, which can be used in the form of blocks, sheets or as an aggregate material for cementitious composites. The objective of this work is to analyze the physical and mechanical properties of mortar when they have the addition of EPS in their composition, which is formed by water, sand and cement. The results are obtained by making prismatic specimens of mortar with partial replacement of fine aggregate (sand) by EPS in the proportions of 0.50%, 1.00% and 1.50% by mass. For the physical properties, water absorption, void ratio and specific mass were studied and for the mechanical properties, the specimens were ruptured by bending and compression. The results prove that the use of EPS in the cementitious matrix of the mortar significantly reduces the final weight of the material, providing a decrease in the specific mass and an increase in the void index, which, on the other hand, leads to a decrease in mechanical strengt

Arte e tecnologia: da idéia de reprodução técnica de Walter Benjamin às propostas de Museu Virtual

O presente artigo pretende observar as funções documental e artística da fotografia, bem como relacioná-las às noções de reprodução técnica/mecânica abordada por Walter Benjamin. Com base nisso, discutiremos o conceito de “museu virtual” que se tem apresentado na literatura desde meados da década de 1990, mais precisamente após o surgimento da Internet. Propomos que o museu virtual seria apenas o espaço na Internet que apresenta obras produzidas por meio de softwares, por e para o meio virtual. Em contrapartida, definimos os espaços virtuais que apresentam reproduções de fotografias de obras de arte tradicionais como Catálogos Hipertextuais.The present paper aim to observe documental and artistic functions of photography, as well as to relate it to notions such as technical/ mechanical reproduction, as presented by Walter Benjamin. On this ground, we discuss the concept of “virtual museum”, as it has been presented since the middle of the ’90, more exactly after the downing of Internet. We defend the Idea that virtual museums are only those made by art works generated by and for the virtual medium through softwares and we define Hypertextual Cathalogs those that offer photographic reproductions of physical art works.Cet article a pour but d’observer les fonctions documentaire et artistique de la photographie ainsi que de mettre em relation les notions de reprodution thechnique/mecanique abordées par Walter Benjamin. Sur cette base, nous nous pencherons sur le concept de «musée virtuel», present dans la litterature depuis le milieu des anées 1990, plus precisément après l’émergence d’internet. Nous proposons une definition du «musée virtuel» en tant qu’espace compose d’oeuvres qui n’existent pas dans le monde reel comme un objet physique, mais seulement sur internet. En contrepartie, les sites internet proposant des photocopies d’oeuvres physiques ne peuvent être considerée comme «musée virtuel», ils sont pour nous seulement des Catalogue Hypertextuelles

Pyrenees deformation monitoring using Sentinel-1 data and the Persistent Scatterer Interferometry technique

This study focuses on deformation mapping and monitoring using Sentinel-1 radar data and the DInSAR (Differential Interferometric Synthetic Aperture Radar) technique. In particular, a Persistent Scatterer Interferometry technique was used over 15000 ¿¿¿¿2 of the Pyrenees, located in Spain, Andorra and France. The main goal is to monitor deformations over a vegetated and mountainous region by exploiting the wide-area coverage, the high coherence and temporal sampling provided by the Sentinel-1satellites. All possible interferograms were generated using 150 images covering five years. The velocity map of the entire region is presented considering the characteristics of the study area, including vegetation and severe steep mountains. Two areas of deformation are shown, which are characterized by velocity values ranging between -20 to -40 mm/year.The work of S.M. Mirmazloumi has been funded by the Spanish State Research Agency, through a grant for a pre doctorate contract (Ref: PRE2018-083394). This work has been co-funded by the European Regional Development Fund through the Interreg V-A Spain, France and Andorra (POCTEFA 2014-2020), project EFA295/19Peer ReviewedPostprint (published version

Measuring thermal expansion using X-band Persistent Scatterer Interferometry

This paper is focused on the estimation of the thermal expansion of buildings and infrastructures using X-band Persistent Scatterer Interferometry (PSI) observations. For this purpose an extended PSI model is used, which allows separating the thermal expansion from the total observed deformation thus generating a new PSI product: the map of the thermal expansion parameter, named thermal map. The core of the paper is devoted to the exploitation of the information contained in the thermal maps: three examples are discussed in detail, which concern a viaduct, a set of industrial buildings and two skyscrapers. The thermal maps can be used to derive the thermal expansion coefficient of the observed objects and information on their static structure. In addition, the paper illustrates the distortions in the PSI deformation products that occur if the thermal expansion is not explicitly modelled. Finally, an inter-comparison exercise is described, where the thermal expansion coefficients estimated by PSI are compared with those derived by a Ku-band ground-based SAR campaign

Systematic exploitation of the persistent scatterer interferometry potential

This paper briefly addresses the problem of exploiting the potential of Persistent Scatterer Interferometry (PSI) data. This has always been an open issue with the previous SAR missions. With Sentinel-1 it is becoming even more important due to its high throughput. Current data processing capabilities allow us to process a fraction of the acquired data; and the data analysis and exploitation only cover a part of the PSI results. From one side the PSI processing tools require to be improved, while from the other side there is the need of increasing the capabilities to analyze and interpret the PSI results, thus exploiting their potential

Deformation monitoring using Persistent Scatterer Interferometry and Sentinel-1 SAR data

During the last decades, Persistent Scatterer Interferometry (PSI) has demonstrated to be a powerful tool able to measure and monitor deformations. This technique makes use of large stacks of interferometric SAR images to derive the deformation maps and deformation time series. In this paper, Sentinel-1 images are used to derive the deformation monitoring over the Catalonia region (Spain). These images brings new improvements due to its wide coverage and high revisiting time, which allows us to make a wide area processing. The first part of the paper describes the data processing implemented by the authors to analyze Sentinel-1 data and the PSI approach used in this ongoing research. The second part of the paper illustrates the results derived over an area of 6750 km2 using Sentinel-1 images

Differential SAR interferometry for the monitoring of land subsidence along railway infrastructures

The paper summarizes the results of an ongoing research project carried out in cooperation between CTTC (Spain) and the University of Milan (Italy). The work aimed at investigating the role of quality indicators in the analysis of differential interferometric SAR time series products. Small baseline multi-temporal differential interferometric techniques have been used to derive TS products from six-year Sentinel-1 images covering railway networks in Barcelona, Spain. Redundancies of interferograms and post-phase unwrapping phase estimation residuals were pivotal parameters in determining the reliabilities of measurements. Preliminary results have supported the importance of quality indicators as well as the feasibility of multi-temporal differential interferometric techniques in monitoring subsidence along railway infrastructures. The time series evolutions of measurements from coherent scatterers have also shown that the target area is stable in the study period.AGAUR, Generalitat de Catalunya, has partially funded this work through a grant to recruit early-stage research staff (Ref: 2021FI_B2_00186).Peer ReviewedPostprint (published version

Spatio-temporal quality indicators for differential interferometric Synthetic Aperture Radar data

Satellite-based interferometric synthetic aperture radar (InSAR) is an invaluable technique in the detection and monitoring of changes on the surface of the earth. Its high spatial coverage, weather friendly and remote nature are among the advantages of the tool. The multi-temporal differential InSAR (DInSAR) methods in particular estimate the spatio-temporal evolution of deformation by incorporating information from multiple SAR images. Moreover, opportunities from the DInSAR techniques are accompanied by challenges that affect the final outputs. Resolving the inherent ambiguities of interferometric phases, especially in areas with a high spatio-temporal deformation gradient, represents the main challenge. This brings the necessity of quality indices as important DInSAR data processing tools in achieving ultimate processing outcomes. Often such indices are not provided with the deformation products. In this work, we propose four scores associated with (i) measurement points, (ii) dates of time series, (iii) interferograms and (iv) images involved in the processing. These scores are derived from a redundant set of interferograms and are calculated based on the consistency of the unwrapped interferometric phases in the frame of a least-squares adjustment. The scores reflect the occurrence of phase unwrapping errors and represent valuable input for the analysis and exploitation of the DInSAR results. The proposed tools were tested on 432,311 points, 1795 interferograms and 263 Sentinel-1 single look complex images by employing the small baseline technique in the PSI processing chain, PSIG of the geomatics division of the Centre Tecnològic de Telecomunicacions de Catalunya (CTTC). The results illustrate the importance of the scores—mainly in the interpretation of the DInSAR outputs.This research was partially funded by the Agència de Gestió d’Ajuts Universitaris i de Recerca (AGAUR), Generalitat de Catalunya—through a grant for the recruitment of early-stage research staff (Ref: 2021FI_B2 00186).Peer ReviewedPostprint (published version

Interferometric SAR deformation timeseries: a quality index

Estimating unknown absolute phase from a wrapped observation is a challenging and ill-posed problem that possibly leads to misinterpretation of interferometric SAR (InSAR) deformation results. In this study, we introduce a quality index to cluster post-phase unwrapping multi-master InSAR timeseries outputs based on the estimated phase residuals and redundancy of network of interferograms. The index is supposed to indicate the reliability of a timeseries, including the identification of persistent scatterers (PSs) possibly affected by phase unwrapping jumps. The algorithm was tested on two Sentinel-1 interferometric datasets with 622,991 and 95,398 PSs, generated from the PSI processing chain PSIG of the geomatics division of CTTC. Promising result have been achieved-especially in identifying erroneous PSs with phase unwrapping jumps. Along with existing temporal phase consistency checking algorithms, the approach could provide rich information toward a better interpretation of the deformation timeseries results.This work has been funded by AGAUR, Generalitat de Catalunya, in the framework of Resolution EMC/ 2459/2019, FI-2020.Peer ReviewedPostprint (published version

extracellular enzymatic activities of 32 fungal species

Se investigó en 32 especies fúngicas, la producción de enzimas extracelulares y ms determinaciones cualitativas (amilasa, celulosa, caseinasa, fosfatasa, lipasa, pectinasa y ureasa). La detección de los enzimas en los cultivos fúngicos en agar varió ampliamente.En la mayoría de los cultivos fúngicos se detectaron: amilasas, ureasas, y fosfatasas. Las celulosas se pesquizaron particularmente en cultivo de Aspergillus flavus, A. fumigatus, Cladosporium cladosporioides Penicillium brevicompactum, Rhizopus stolonifer, Scopulariopsis flava y Trichothecium roseum. Penicillium digitatum y P.duclauxi fueron productores de caseinasa en un alto grado. La actividad lipolítica se detectó en cultivos con grasas sintéticas tweens 20, 40, 60, y 80 como sustrato para lipasa. Indicaron actividad lipolítico para estos sustratos A. flavus, Aureobasidium pullulans, C. cladosporioides, Gliocladium roseum, Mycothypha microspora, Microsporum gypseum, P. brevicompactum y Scopulariopsis brumptii. Productores de pectinasas fueron las cepas de A. flavus, C. cladosporioides y Fusarium oxysporum, P. brevicompoctum y Ulocladium atru