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The application of deep learning (DL) algorithms to Earth observation (EO) in recent years has enabled substantial progress in fields that rely on remotely sensed data. However, given the data scale in EO, creating large datasets with pixel-level annotations by experts is expensive and highly time-consuming. In this context, priors are seen as an attractive way to alleviate the burden of manual labeling when training DL methods for EO. For some applications, those priors are readily available. Motivated by the great success of contrastive-learning methods for self-supervised feature representation learning in many computer-vision tasks, this study proposes an online deep clustering method using crop label proportions as priors to learn a sample-level classifier based on government crop-proportion data for a whole agricultural region. We evaluate the method using two large datasets from two different agricultural regions in Brazil. Extensive experiments demonstrate that the method is robust to different data types [synthetic-aperture radar (SAR) and optical images], reporting higher accuracy values considering the major crop types in the target regions. Thus, it can alleviate the burden of large-scale image annotation in EO applications.

[PO] Após mais de dois milênios de história da mineração, Espanha e Portugal produzem juntos cerca de mil milhões de toneladas de rochas e minerais industriais a cada ano. Em Espanha e Portugal, a indústria das rochas ornamentais e minerais industriais desenvolveu-se significativamente nos últimos anos. A demanda por materiais de construção e ornamentais aumentou e ambos os países emergiram como líderes mundiais na produção de mármore e outros produtos ornamentais. Apesar dos desafios ambientais e competitivos, a indústria continua lucrativa e em constante crescimento.

[EN] The volcanism in the Iberian Pyrite Belt migrated from the present day west/southwest to the east/northeast during Devonian/Carboniferous times. Evidence is here discussed based in U-Pb zircon ages of felsic volcanic and plutonic rocks, bounded by enclosed sediments and their biostratigraphic ages, together with hosted massive sulphides deposits and associated plutonic counterparts. Volcano-Sedimentary Complex rocks define several volcanic axes, or lineaments, with the general NW-SE to WNW-ESE belt trending orientation. The usage of all the available data from high-resolution stratigraphy, geology and geophysics lead to establishment of eleven main volcanic axes, nine with zircon U-Pb radiometric ages (166 samples). In this research, we reinforce a previous inter-axes volcanic evolutionary trend, but we also suggest an intra-axis evolutionary trend of the IPB igneous activity with time. This means the basin igneous activity also evolved along most of the volcanic and plutonic lineaments, from west/northwest to east/southeast. Successive weighted average ages for each axis (SW to NE) and opposite end-point sample ages for each axis (NW/W to SE/E) are presented. Similar trends are found with felsic volcanic rocks, subvolcanic and plutonic rocks and even massive sulphide ages correspond to the regional trend corroborating the proposed geological framework. Siliciclastic sediments and lower VSC sequences (sediments, felsic volcanic rocks and massive sulphides) show a comparable age trending evolution although upper VSC sediments seem to be contemporaneous across the province. Older ages, from zircon U-Pb and from associated reworked palynomorph in the sediments, show a long-lasting age distribution along most Devonian times, suggesting the IPB evolved since Lochkovian times (Lower Devonian). Therefore, we propose the IPB inter-axes evolution could be related with a NE-direction plate motion (present-day location) over a heat source, while intra-axes are probably du

In this work, the digital image correlation (DIC) technique was used to evaluate the fiber cement deformation process. The composites were produced with partial replacement of cement by construction and demolition waste (CDW), in the contents of 0, 5, 10, and 15% by mass, and 10% of eucalyptus kraft pulp bleached by the slurry-dewatering and pressurization method. After the curing process, the fiber cement was subjected to bending at four points and monitored by cameras, responsible for photographic records every 2 seconds. The composites were analyzed with image correlation technology, where the deformation stages of the composites could be observed. In general, through the use of the DIC technique, it was possible to identify regions of greater deformation, areas of stress concentration, and possible failures or critical points, in addition to having enabled the identification of the failure mode of the composites.

In recent years, there has been a growing concern regarding the reduction of extraction of non-renewable raw materials through the utilization of alternative and eco-efficient materials such as waste, pozzolans, and natural fibers. Thus, the study aims to investigate the feasibility of reducing the cement content in composites without compromising their physic-mechanical properties. The composite was manufactured with 45% cement, 50% metakaolin, and 5% construction and demolition waste, utilizing hornified jute and mallow fibers measuring 20 mm in length as reinforcement. The water-to-solid ratio was set at 0.4, with the inclusion of a superplasticizer additive at a concentration of 0.8%. Cubic samples were molded and subjected to an initial cure of 48 hours. Subsequently, the samples were divided into two groups. Group I underwent thermal curing for duration of five days, while Group II was subjected to an accelerated carbonation process lasting 9 h. The physic-mechanical properties were analyzed. The results demonstrate that the accelerated carbonation process led to a reduction in water absorption and apparent porosity of the fiber cement, also increasing the compressive strength by 7%. Overall, it was observed that the accelerated carbonation process during the early stages contributed to the enhancement of the physic-mechanical properties of the fiber cement.