SCENES: Subpixel Correspondence Estimation With Epipolar Supervision

Extracting point correspondences from two or more views of a scene is a fundamental computer vision problem with particular importance for relative camera pose estimation and structure-from-motion. Existing local feature matching approaches, trained with correspondence supervision on large-scale datasets, obtain highly-accurate matches on the test sets. However, they do not generalise well to new datasets with different characteristics to those they were trained on, unlike classic feature extractors. Instead, they require finetuning, which assumes that ground-truth correspondences or ground-truth camera poses and 3D structure are available. We relax this assumption by removing the requirement of 3D structure, e.g., depth maps or point clouds, and only require camera pose information, which can be obtained from odometry. We do so by replacing correspondence losses with epipolar losses, which encourage putative matches to lie on the associated epipolar line. While weaker than correspondence supervision, we observe that this cue is sufficient for finetuning existing models on new data. We then further relax the assumption of known camera poses by using pose estimates in a novel bootstrapping approach. We evaluate on highly challenging datasets, including an indoor drone dataset and an outdoor smartphone camera dataset, and obtain state-of-the-art results without strong supervision

A new perspective for robustness assessment of framed structures

Robustness has been recognized as interesting research topic due to several collapses that have been occurring over last years. Indeed, this subject is related with global failure or collapse. However, its definition is not consensual since several definitions have been proposed in the literature. This shortpaper aims to present a framework for assessing bridge’s robustness as a probabilistic performance indicator. In this study, a non-linear model of a clamped beam with two point loads using DIANA software was developed to validate the framework presented. By means of a probabilistic approach, the load carrying capacity and structural safety were evaluated. In this regard, special focus is placed on an adaptive Monte Carlo simulation procedure to achieve a proper meta-model.ISISE – Institute for Sustainability and Innovation in Structural Engineering (PEstC/ECI/UI4029/2011 FCOM-01-0124-FEDER-022681)FCT– Portuguese Scientific Foundation for the research grant PD/BD/113677/2015European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement No. 60622

Al-containing MCM-41 type materials prepared by different synthesis methods: hydrothermal stability and catalytic properties

Al-containing MCM-41 type materials were prepared by three different synthesis methods (aluminum grafting on the calcined MCM-41, pH adjustment during the crystallization period and crystallization in the presence of zeolite seeds). The samples were characterized by powder XRD, nitrogen adsorption, 27Al MAS NMR and FTIR with pyridine as probe molecule. All the samples exhibit a high hydrothermal stability at high temperature just with a minor structural degradation. N2 adsorption data obtained for the sample prepared from a gel containing zeolite seeds suggest a higher structural resistance to the hydrothermal treatment in comparison with the samples prepared by other methods. A different type of pyridine adsorbed, probably interacting simultaneously with a Brönsted and a Lewis acid site, is observed upon pyridine adsorption. This type of adsorption is stronger for the sample prepared in the presence of zeolite seeds and is not observed on Al-grafted MCM-41. 2 The catalytic activity towards the isomerization of α-pinene depends mainly on the number of Brönsted acid sites. The data obtained in this study strongly indicate that for this type of materials, the Lewis acid sites do not influence the selectivity for the isomerization products

Marine Snails of the Genus Phorcus: Biology and Ecology of Sentinel Species for Human Impacts on the Rocky Shores

In this review article, the authors explore a broad spectrum of subjects associated to marine snails of the genus Phorcus Risso, 1826, namely, distribution, habitat, behaviour and life history traits, and the consequences of anthropological impacts, such as fisheries, pollution, and climate changes, on these species. This work focuses on discussing the ecological importance of these sentinel species and their interactions in the rocky shores as well as the anthropogenic impacts to which they are subjected. One of the main anthropogenic stresses that affect Phorcus species is fisheries. Topshell harvesting is recognized as occurring since prehistoric times and has evolved through time from a subsistence to commercial exploitation level. However, there is a gap of information concerning these species that hinders stock assessment and management required for sustainable exploitation. Additionally, these keystone species are useful tools in assessing coastal habitat quality, due to their eco-biological features. Contamination of these species with heavy metals carries serious risk for animal and human health due to their potential of biomagnification in the food chain. Thus, the use of these species as bioindicators is warranted to the establishment of conservation measures targeting marine coastal environments. Climate change increases the level of environmental stress to which intertidal organisms are subjected to, affecting the functioning of biological systems at different levels of organization. Phorcus species have been widely used as indicators of the effect of climate change on local disturbances of intertidal ecosystems and geographic distribution shifts of these organisms. Further studies concerning biological parameters of Phorcus species and how they react to exploitation, pollution, and climate change will consolidate these species as indicators of large-scale ecological impacts of anthropogenic activities

Modelling the phenological development of cv. Touriga Nacional and Encruzado in the Dão Wine Region, Portugal

The grapevine vegetative cycle, which is morphologically described by its phenological stages, is strongly determined by weather conditions. Phenological models are widely applied in viticulture and are based on the assumption that air temperature is the preponderant environmental factor which determines vine development. In this study, phenological development models (PDMs) were calibrated and validated to simulate several intermediate stages between budbreak and veraison for cv. Touriga Nacional (TN) and cv. Encruzado (EN) winegrape varieties, which are widely grown in the Dao Wine Region, Portugal. These are thermal models, with which the daily sum of the rate of forcing (R) was calculated using a sigmoid function. For this purpose, a high-quality and comprehensive dataset was used which combines phenology data and weather station data in several vineyard sites spread over the region. The model showed an overall high performance (global RMSE of 5.4 days for EN and 5.0 days for TN), although it depended on the phenological stage and variety. The RMSE ranged from 3.2 to 6.2 for TN, and from 3.9 to 6.8 for EN. For both varieties and in all phenological stages, the RMSE was significantly lower than the standard deviation of the phenological observations. For TN, the model efficiency was greater than 0.71 for all phenological stages. In future studies, these models will be combined with specific models that simulate the evolution of winegrape berry quality indicators commonly used for harvest decision support. The relatively low complexity of the selected PDMs enables their use as a crop management and decision support tool. To our knowledge, no previous studies have been carried out on either of these two varieties and their intermediate phenological timings. The present study is an illustration of conceivable model development under diverse environmental conditions, thus allowing similar approaches to be adopted in other wine regions on a worldwide scale.info:eu-repo/semantics/publishedVersio

A sound approach: using large language models to generate audio descriptions for egocentric text-audio retrieval

Video databases from the internet are a valuable source of text-audio retrieval datasets. However, given that sound and vision streams represent different "views" of the data, treating visual descriptions as audio descriptions is far from optimal. Even if audio class labels are present, they commonly are not very detailed, making them unsuited for text-audio retrieval. To exploit relevant audio information from video-text datasets, we introduce a methodology for generating audio-centric descriptions using Large Language Models (LLMs). In this work, we consider the egocentric video setting and propose three new text-audio retrieval benchmarks based on the EpicMIR and EgoMCQ tasks, and on the EpicSounds dataset. Our approach for obtaining audio-centric descriptions gives significantly higher zero-shot performance than using the original visual-centric descriptions. Furthermore, we show that using the same prompts, we can successfully employ LLMs to improve the retrieval on EpicSounds, compared to using the original audio class labels of the dataset. Finally, we confirm that LLMs can be used to determine the difficulty of identifying the action associated with a sound

3D-Printing of paracetamol tablets by fused deposition modelling

Abstract of poster presented at the 12th PBP World Meeting on Pharmaceutics, Biopharmaceutics and Pharmaceutical Technology, Wien, Austria, 11-14 May 2021 (virtual Meeting)N/

Disentangling exploitation of the intertidal grazer Phorcus sauciatus (Gastropoda: Trochidae) in an oceanic archipelago: implications for conservation

Harvesting of intertidal grazers such as topshells is known to affect negatively the exploited populations by altering population structure and decreasing abundance. Phorcus sauciatus has a wide geographic distribution in the North‐eastern Atlantic Ocean and is subject to increasing levels of harvesting pressure due to the expansion of human population on coastal areas. The effect of proximity to human settlements and coastal accessibility on the size structure and abundance of P. sauciatus popula‐ tions was examined in Madeira archipelago. Mean size, proportion of reproductive individuals, and abundance of this species were generally smaller in areas closer to human settlements and in more accessible coastal areas. Marine protected areas re‐ turned the highest mean sizes evidencing their effectiveness in preserving the size structure of this species. The results highlight the necessity to regulate the harvest of P. sauciatus in Madeira archipelago, as well as the implementation of management measures aiming at the sustainable exploitation and conservation of this species, ex‐ ploited in this region since the early 15th century.info:eu-repo/semantics/publishedVersio

Study of the stability of acetaminophen extrudates for 3D printing prepared by hot melt extrusion when stored at different relative humidites

Poster presented at the PSWC2020 Virtual (7th FIP Pharmaceutical Sciences World Congress), 4-6 October 2020N/

Filling biological information gaps of the marine topshell Phorcus sauciatus (Gastropoda: Trochidae) to ensure its sustainable exploitation

Topshells play a pivotal role in intertidal rocky ecosystems and are adapted to harsh thermal and hydric stress. Phorcus sauciatus, a common grazer in the Macaronesian region (Madeira and the Canaries), has rarely been studied due to its restricted geographic distribution com pared with Phorcus lineatus. Monthly samples were taken throughout 2017 to analyse biological parameters and evaluate the harvesting effect on the stocks of this species in Madeira. Individuals of the first age classes (<4 years) were dominant (∼89%), while immature indivi duals were more abundant during the summer season. The spawning season occurs between March and August, especially from March to June. The size at first maturity was 12.95 mm long (1.68 years), with a continuous recruitment pattern throughout the year. Yield-per-recruit analysis (Y/R) showed that maximum production is achieved at a fishing mortality of 1.7 year−1 , corresponding to a Y/R of 0.023 g. Currently, Phorcus sauciatus seems to be mod erately exploited in Madeira, but urgent conservation measures, such as a landing obligation, the establishment of a minimum catch size of 15 mm length, and a closed season (February–May), are warranted to preserve stocks of this species in the medium to long term.info:eu-repo/semantics/publishedVersio