242 research outputs found
A multispectral omnidirectional stereoscopic sensor
The 3D reconstruction of an environment with a high degree of accuracy and faithful textures represents an important
challenge for applications related to the multimedia and cinematography. We present in this article, the complete
development, of the electronic design to the algorithmic restitution of the environment, of a multispectral omnidirectional
stereoscopic sensor that tackles this problem. Although panoramic sensors exist, the vision system presented here has
four channels of acquisition coupled to a projector of structured light emitting in the infra-red. This original process
separates the acquisition of colors textures independently of the 3D reconstruction. The panoramic images colors are
corrected starting from ICC (International Color Consorsium) profiles of the two cameras. The reconstruction of the environment uses only the invariable available on the infra-red channels. An active calibration technique is also
presented. Experimental results demonstrate the feasibility of this new class of multispectral omnidirectionnal vision
sensor.La reconstruction dâun environnement avec une grande prĂ©cision et des textures fidĂšles reprĂ©sente un besoin
important pour des applications liĂ©es aux mondes de lâĂ©vĂ©nementiel, de la cinĂ©matographie et du
multimédias. Nous présentons dans cet article, le développement complet, de la conception électronique à la
restitution algorithmique de lâenvironnement, dâun systĂšme de vision stĂ©rĂ©oscopique omnidirectionnel multi
spectral permettant de rĂ©pondre Ă ce besoin. Lâarchitecture du systĂšme prĂ©sentĂ©e ici, possĂšde la particularitĂ©
dâavoir deux camĂ©ras (munies de quatre canaux dâacquisition) couplĂ©es Ă un projecteur de lumiĂšre structurĂ©e
infrarouge. Ce procĂ©dĂ© original dâacquisition traite le processus dâobtention des textures couleurs
indépendamment de celui de la reconstruction 3D. Les images panoramiques couleurs sont corrigées à partir
des profils ICC (International Color Consorsium) des deux camĂ©ras. La reconstruction 3D de lâenvironnement
utilise les informations disponibles sur les canaux infrarouges des deux caméras. Une étape préliminaire de
calibrage actif est aussi présentée. Des résultats expérimentaux démontrent la faisabilité de cette nouvelle
classe de capteur de vision multi spectrale omnidirectionnelle
MineralizaçÔes aurĂferas nos grupos serra do Itaberaba e SĂŁo Roque entre Guarulhos e Santa Isabel-SP
Hybrid Model Based on Genetic Algorithms and SVM Applied to Variable Selection Within Fruit Juice Classification
Research article[Abstract] Given the background of the use of Neural Networks in problems of apple juice classification, this paper aim at implementing a newly developed method in the field of machine learning: the Support Vector Machines (SVM). Therefore, a hybrid model that combines genetic algorithms and support vector machines is suggested in such a way that, when using SVM as a fitness function of the Genetic Algorithm (GA), the most representative variables for a specific classification problem can be selected
Geochemistry of tourmalines associated with iron formation and quartz veins of the Morro da Pedra Preta Formation, Serra do Itaberaba Group (Sao Paulo, Brazil)
Tourmalines of intermediate schorl-dravite composition occur in iron formation (including metachert and tourmalinites), metasediments, calc-silicate and metabasic/intermediate rocks of the Morro da Pedra Preta Formation, a volcanic-sedimentary sequence of the Serra do Itaberaba Group (northeast of Sao Paulo City, southeastern Brazil). The Morro da Pedra Preta Formation is crosscut by quartz veins that contain both intermediate schorl-dravite and an alkali-deficient, Cr-(V-)bearing tourmaline, in which the occupancy of the X-site is rectangle(0.51)Ca(0.33)Na(0.15), characterizing it as intermediate to foitite and magnesiofoitite end-members. Mg# values for this tourmaline are higher than those for intermediate schorl-dravite. Raman spectroscopy also confirms the presence of two groups of tourmalines. Stable isotope data indicate sediment waters as fluid sources, rather than fluids from magmatic/post-magmatic sources. Delta(18)O compositions for tourmalines, host metachert, and quartz veins are similar, showing that fluid equilibration occurred during crystallization of both quartz and tourmaline. Syngenetic, intermediate schorl-dravite tourmalines were formed under submarine, sedimentary-exhalative conditions; amphibolite-grade metamorphism did not strongly affect their compositions. Younger tourmalines of compositions intermediate to foitite and magnesiofoitite reflect the composition of the host rocks of quartz veins, due to fluid percolation along faults and fractures that caused leaching of Cr (and V) and the crystallization of these alkali-deficient, Cr-(V-)bearing tourmalines.75220923
Complexes of bifunctional DO3A-N-(α-amino)propinate ligands with Mg(II), Ca(II), Cu(II), Zn(II), and lanthanide(III) ions: thermodynamic stability, formation and dissociation kinetics, and solution dynamic NMR studies
The thermodynamic, kinetic, and structural properties of Ln3+ complexes with the bifunctional DO3A-ACE4â ligand and its amide derivative DO3A-BACE4â (modelling the case where DO3A-ACE4â ligand binds to vector molecules) have been studied in order to confirm the usefulness of the corresponding Gd3+ complexes as relaxation labels of targeted MRI contrast agents. The stability constants of the Mg2+ and Ca2+ complexes of DO3A-ACE4â and DO3A-BACE4â complexes are lower than for DOTA4â and DO3A3â, while the Zn2+ and Cu2+ complexes have similar and higher stability than for DOTA4â and DO3A3â complexes. The stability constants of the Ln(DO3A-BACE)â complexes increase from Ce3+ to Gd3+ but remain practically constant for the late Ln3+ ions (represented by Yb3+). The stability constants of the Ln(DO3A-ACE)4â and Ln(DO3A-BACE)4â complexes are several orders of magnitude lower than those of the corresponding DOTA4â and DO3A3â complexes. The formation rate of Eu(DO3A-ACE)â is one order of magnitude slower than for Eu(DOTA)â, due to the presence of the protonated amine group, which destabilizes the protonated intermediate complex. This protonated group causes the Ln(DO3A-ACE)â complexes to dissociate several orders of magnitude faster than Ln(DOTA)â and its absence in the Ln(DO3A-BACE)â complexes results in inertness similar to Ln(DOTA)â (as judged by the rate constants of acid assisted dissociation). The 1H NMR spectra of the diamagnetic Y(DO3A-ACE)â and Y(DO3A-BACE)â reflect the slow dynamics at low temperatures of the intramolecular isomerization process between the SA pair of enantiomers, R-Î(λλλλ) and S-Î(ÎŽÎŽÎŽÎŽ). The conformation of the Cα-substituted pendant arm is different in the two complexes, where the bulky substituent is further away from the macrocyclic ring in Y(DO3A-BACE)â than the amino group in Y(DO3A-ACE)â to minimize steric hindrance. The temperature dependence of the spectra reflects slower ring motions than pendant arms rearrangements in both complexes. Although losing some thermodynamic stability relative to Gd(DOTA)â, Gd(DO3A-BACE)â is still quite inert, indicating the usefulness of the bifunctional DO3A-ACE4â in the design of GBCAs and Ln3+-based tags for protein structural NMR analysis.This research was funded by the Hungarian National Research, Development and Innovation Office (Projects NKFIH K-128201, K-134694, and FK-134551)
Vulcanismo recorrente e feiçÔes geolĂłgicas afins em diques bĂĄsico ultrabĂĄsicos da Praia Vermelha do Sul, municĂpio de Ubatuba/SP
Chemical-protein relation extraction with ensembles of carefully tuned pretrained language models
The identification of chemical-protein interactions described in the literature is an important task with applications in drug design, precision medicine and biotechnology. Manual extraction of such relationships from the biomedical literature is costly and often prohibitively time-consuming. The BioCreative VII DrugProt shared task provides a benchmark for methods for the automated extraction of chemical-protein relations from scientific text. Here we describe our contribution to the shared task and report on the achieved results. We define the task as a relation classification problem, which we approach with pretrained transformer language models. Upon this basic architecture, we experiment with utilizing textual and embedded side information from knowledge bases as well as additional training data to improve extraction performance. We perform a comprehensive evaluation of the proposed model and the individual extensions including an extensive hyperparameter search leading to 2647 different runs. We find that ensembling and choosing the right pretrained language model are crucial for optimal performance, whereas adding additional data and embedded side information did not improve results. Our best model is based on an ensemble of 10 pretrained transformers and additional textual descriptions of chemicals taken from the Comparative Toxicogenomics Database. The model reaches an F1 score of 79.73% on the hidden DrugProt test set and achieves the first rank out of 107 submitted runs in the official evaluation. Database URL: https://github.com/leonweber/drugprot
Examining the efficacy of a self-administered report form in missing person investigations
PurposeThe success of missing person investigations often centres on the quality of information obtained in the early stages. Reliable information can not only inform the search but might also become vital evidence if the case broadens into a criminal investigation relating to a sexual offence, abduction, or even murder. In addition to eliciting high quality information, police officers must consider that those close to the missing person are likely going through a very difficult and stressful time. Across two studies, we developed and tested a self-administered form (SAI-MISSING) designed to obtain reliable information that would meaningfully inform a missing person investigation, as well as providing a means for family and friends to be actively involved.MethodsIn Experiment 1, 65 participants were tested individually and asked to provide a description of a person they knew well but had not seen for 24 hours. In the second study, 64 participants were tested in pairs, but immediately separated into different rooms and instructed to imagine that the person they came with has gone missing. In both studies participants completed either the SAI-MISSING tool, or a self-administered control form.ResultsIn Experiment 1 we found that the SAI-MISSING tool elicited significantly more information regarding physical descriptions and descriptions of clothing and personal effects, than the comparison control form. In Experiment 2 we replicated this finding, and further showed that the SAI-MISSING tool produced higher accuracy rates than the control form.ConclusionsGiven our positive findings, potential applications of the tool are discussed
Geochemistry of tourmalines associated with iron formation and quartz veins of the Morro da Pedra Preta Formation, Serra do Itaberaba Group (SĂŁo Paulo, Brazil)
The inventory of geological heritage of the state of SĂŁo Paulo, Brazil: Methodological basis, results and perspectives
An inventory of geological sites based on solid and clear criteria is a first step for any geoconservation strategy. This paper describes the method used in the geoheritage inventory of the State of SĂŁo Paulo, Brazil, and presents its main results. This inventory developed by the geoscientific community aimed to identify geosites with scientific value in the whole state, using a systematic approach. All 142 geosites representative of 11 geological frameworks were characterised and quantitatively evaluated according to their scientific value and risk of degradation, in order to establish priorities for their future management. An online database of the inventory is under construction, which will be available to be easily consulted and updated by the geoscientific community. All data were made available to the State Geological Institute as the backbone for the implementation of a future state geoconservation strategy.The authors acknowledge the Science Without Borders Programme, Process 075/2012, which supported this study and the SĂŁo Paulo Research Foundation (FAPESP), Process 2011/17261-6. We also thanks C. Mazoca for his help with maps and figures.info:eu-repo/semantics/acceptedVersio
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