UNDERWATER COMPARISON OF WAND AND 2D PLANE NONLINEAR CAMERA CALIBRATION METHODS

The purpose of this study was to compare two nonlinear camera calibration methods for 3D underwater motion analysis. The DVideo kinematic analysis system was used for underwater online data acquisition. The system consisted of two gen-locked Basler cameras working at 100Hz, with wide angle lenses that were enclosed in housings. The accuracy of both methods was compared in a dynamic rigid bar test. The mean absolute errors were 1.16mm for wand calibration, 1.20mm for 2D plane calibration using 8 control points and 0.73mm for 2D plane calibration using 16 control points. The results of both nonlinear camera calibration methods provided better underwater accuracy than all previous papers reported in literature. Both methods provided similar and highly accurate results, providing promising alternatives for underwater 3D motion analysis

Assessment of habitat suitability for common cockles in the Ria the Aveiro Lagoon under average and projected environmental conditions

The common cockle Cerastoderma edule is a widespread bivalve species inhabiting estuarine systems across the North East Atlantic, where it provides several ecosystem services, and represents a valuable fishery resource for local economies. However, anthropogenic pressure and more frequent extreme weather events threaten the resilience of the species. Spatially explicit information on species distribution is critical for the implementation of management and conservation practices. This study assessed the potential distribution of C. edule in the Ria de Aveiro by estimating the habitat suitability using an ensemble approach based on ecological niche modeling and recently developed hydrodynamic and water quality models to forecast both average and projected estuarine conditions. The models were developed for the summer of 2013 and spring of 2019 and potential range shifts in the species distribution were forecasted under projected environmental conditions: high and low estimates of freshwater discharge, a 2 °C increase in water temperature, and the combined effect of low freshwater discharge and increased water temperature. The results suggest that salinity, time of submersion, and current velocity play an important role in the distribution of cockles, and large areas were consistently classified with high habitat suitability. Increased freshwater discharge (both seasons) and low discharge coupled to increased temperature (spring) resulted in large decreases in suitable habitat. Conversely, low freshwater discharges and average (unchanged) temperatures increased the suitable habitat in the outermost regions of the Ria. The spatially explicit information provided contributes to a better understanding of the vulnerability of C. edule in the Ria de Aveiro to extreme weather events (e.g., droughts, river floods) and may support adaptive management strategies of the cockle fishery during these conditions. Moreover, this approach can be transferred to other estuarine ecosystems for which data describing the environmental conditions (e.g., derived from numerical models), and information about species presence are available (including data-poor species).publishe

On the implementation of the gamma function for image correction on a endoscopic camera

This paper describes part of project that implemented the image processing of a CMOS sensor for endoscopic purposes. The sensor is a small sized device of 1x1mm2 and the image processing has been done inside a FPGA. This part of the work describes the implementation of the Gamma function with a balance between the resources needed and the accuracy. A linear piecewise solution was used that stores the values for 31 gamma functions with values ranging from 1 to 4 with 0.1 steps. The solution developed is 10 bit based, was coded in VHDL and is implemented in a Spartan 6 FPGA. The results show that it is an accurate solution that has a small footprint in terms of used resources.info:eu-repo/semantics/publishedVersio

Full image-processing pipeline in field-programmable gate array for a small endoscopic camera

Endoscopy is an imaging procedure used for diagnosis as well as for some surgical purposes. The camera used for the endoscopy should be small and able to produce a good quality image or video, to reduce discomfort of the patients, and to increase the efficiency of the medical team. To achieve these fundamental goals, a small endoscopy camera with a footprint of 1 mm × 1 mm × 1.65 mm is used. Due to the physical prop erties of the sensors and human vision system limitations, different image-processing algorithms, such as noise reduction, demosaicking, and gamma correction, among others, are needed to faithfully reproduce the image or video. A full image-processing pipeline is implemented using a field-programmable gate array (FPGA) to accomplish a high frame rate of 60 fps with minimum processing delay. Along with this, a viewer has also been developed to display and control the image-processing pipeline. The control and data transfer are done by a USB 3.0 end point in the computer. The full developed system achieves real-time processing of the image and fits in a Xilinx Spartan-6LX150 FPGA.info:eu-repo/semantics/publishedVersio

DESiRED -- Dynamic, Enhanced, and Smart iRED: A P4-AQM with Deep Reinforcement Learning and In-band Network Telemetry

Active Queue Management (AQM) is a mechanism employed to alleviate transient congestion in network device buffers, such as routers and switches. Traditional AQM algorithms use fixed thresholds, like target delay or queue occupancy, to compute random packet drop probabilities. A very small target delay can increase packet losses and reduce link utilization, while a large target delay may increase queueing delays while lowering drop probability. Due to dynamic network traffic characteristics, where traffic fluctuations can lead to significant queue variations, maintaining a fixed threshold AQM may not suit all applications. Consequently, we explore the question: \textit{What is the ideal threshold (target delay) for AQMs?} In this work, we introduce DESiRED (Dynamic, Enhanced, and Smart iRED), a P4-based AQM that leverages precise network feedback from In-band Network Telemetry (INT) to feed a Deep Reinforcement Learning (DRL) model. This model dynamically adjusts the target delay based on rewards that maximize application Quality of Service (QoS). We evaluate DESiRED in a realistic P4-based test environment running an MPEG-DASH service. Our findings demonstrate up to a 90x reduction in video stall and a 42x increase in high-resolution video playback quality when the target delay is adjusted dynamically by DESiRED.Comment: Preprint (Computer Networks under review

Synthesis of the iron(II)-nitrogen complex: concepts of reactivity and back-bonding for undergraduate chemistry students

There has been a considerable interest in coordination complexes of molecular nitrogen (N2), partly due to a possible relationship between such complexes and the nitrogen activation process in nature. The present paper describes the synthesis and infrared spectroscopic characterization of an iron-nitrogen derivative with ethylenediamine-N,N,N',N'-tetraacetate (edta) as an experiment for an undergraduate course. The topics covered here include synthesis, reactivity and spectroscopy.72372

MONITORAMENTO AMBIENTAL DO GLIFOSATO E DO SEU METABÓLITO (ÁCIDO AMINOMETILFOSFÔNICO) NA ÁGUA DE LAVOURA DE ARROZ IRRIGADO

Monitorou-se a presença do herbicida Glifosato e do seu metabólito, ácido aminometilfosfônico (AMPA), em amostras de águas coletadas em área orizícola, submetida a plantio direto. Níveis de Glifosato em concentrações acima do limite máximo permitido (7,0 µg/L) pela Agência de Proteção Ambiental dos Estados Unidos (Environmental Protection Agency) foram detectados. A presença do metabólito AMPA, nas águas dos canais de irrigação, foi detectada até 120 dias após a aplicação (DAA). Pode-se dizer que determinado nível de segurança será alcançado nas águas de lançamento da granja para o Arroio Bretanhas, 120 DAA da formulação de Glifosato. Como não foi observada deserção do Glifosato em GLEYSSOLO HÁPLICO Ta Eutrófico pode-se inferir que a concentração do mesmo permaneceu como resíduo ligado. Assim, a dissipação do herbicida nesse solo pode ser reflexo, entre outros fatores, da formação de resíduo ligado, determinando desta forma o seu destino e/ou comportamento no ambiente. ENVIRONMENTAL MONITORING OF GLYPHOSATE AND ITS METABOLITE (AMINOMETHYLPHOSPHONIC ACID) IN TILLAGE WATER OF IRRIGABLE RICE Abstract Monitor the presence of the herbicide glyphosate and its metabolite, aminomethylphosphonic acid (AMPA), in samples of water collected in orizicole area, subject to direct plantation, was the objective of this study. Levels of glyphosate above the maximum permitted concentration limit (7.0 µg/L) were detected by the United States Environmental Protection Agency (EPA). The presence of the metabolite AMPA in irrigation channel water was detected up to 120 days after application (DAA). It can be deduced that a certain level of safety will be reached 120 DAA from formulation of glyphosate, for water from the Arroio Bretanhas farm. Since the desertion of glyphosate in a Gleyssolo Háplico Ta Eutrophic was not observed, it can be judged that the concentration of it remained as bonded residue. Thus, the dissipation of this herbicide in this soil can be a reflex of, among other factors, the formation of bonded residue, determining, in this manner, its destiny and/or behavior in the environment

AcMus: an open, integrated platform for room acoustics research

This article describes the design, implementation, and experiences with AcMus, an open and integrated software platform for room acoustics research, which comprises tools for measurement, analysis, and simulation of rooms for music listening and production. Through use of affordable hardware, such as laptops, consumer audio interfaces and microphones, the software allows evaluation of relevant acoustical parameters with stable and consistent results, thus providing valuable information in the diagnosis of acoustical problems, as well as the possibility of simulating modifications in the room through analytical models. The system is open-source and based on a flexible and extensible Java plug-in framework, allowing for cross-platform portability, accessibility and experimentation, thus fostering collaboration of users, developers and researchers in the field of room acoustics.CNPqFAPES

Inoculation with the endophytic bacterium Herbaspirillum seropedicae promotes growth, nutrient uptake and photosynthetic efficiency in rice

Main conclusion: Higher vacuolar proton pump activity may increase plant energy and nutrient use efficiency and provide the nexus between plant inoculation with Herbaspirillum seropedicae and growth promotion. Abstract: Global change and growing human population are exhausting arable land and resources, including water and fertilizers. We present inoculation with the endophytic plant-growth promoting bacterium (PGPB) Herbaspirillum seropedicae as a strategy for promoting growth, nutrient uptake and photosynthetic efficiency in rice (Oryza sativa L.). Because plant nutrient acquisition is coordinated with photosynthesis and the plant carbon status, we hypothesize that inoculation with H. seropedicae will stimulate proton (H+) pumps, increasing plant growth nutrient uptake and photosynthetic efficiency at low nutrient levels. Plants were inoculated and grown in pots with sterile soil for 90 days. Herbaspirillum seropedicae endophytic colonization was successful and, as hypothesized, inoculation (1) stimulated root vacuolar H+ pumps (vacuolar H+-ATPase and vacuolar H+-PPase), and (2) increased plant growth, nutrient contents and photosynthetic efficiency. The results showed that inoculation with the endophytic bacterium H. seropedicae can promote plant growth, nutrient uptake and photosynthetic efficiency, which will likely result in a more efficient use of resources (nutrients and water) and higher production of nutrient-rich food at reduced economic and environmental costs.info:eu-repo/semantics/publishedVersio

Porphyrin–nanodiamond hybrid materials—active, stable and reusable cyclohexene oxidation catalysts

funded by FCT-Foundation for Science and Technology, I.P., under projects UIDB/00313/2020; PTDC/QUI-OUT/27996/2017 (DUALPI); POCI-01-0145-FEDER-027996; POCI-01-0145-FEDER-016387; UIDB/50006/2020 (Associate Laboratory for Green Chemistry-LAQV); MATIS (CENTRO-010145-FEDER-00014); Base Funding-UIDB/50020/2020 of the Associate Laboratory LSRE-LCM-funded by national funds through FCT/MCTES (PIDDAC); and 5625-DRI-DAAD-2020/21. SACC also acknowledges FCT Investigador FCT program (IF/01381/2013/CP1160/CT0007) and Scientific Employment Stimulus -Institutional Call (CEECINST/00102/2018). The authors also thank Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP) for CEPOF 2013/07276-1, and INCT "Basic Optics and Applied to Life Sciences" (FAPESP 2014/50857-8, CNPq 465360/2014-9). A.R.L. Caires acknowledges CAPES-PrInt funding program (grant number 88887.353061/2019-00 and 88881.311921/2018-01). J.G.B. thanks the Dutch Research Council (NWO) for funding as a part of the Open Technology Programme (project number 16361). L.D. Dias thanks FAPESP for the Post-doc grant 2019/13569-8. F.M.S.R. thanks FCT for the PhD grant (PD/BD/114340/2016).The quest for active, yet “green” non-toxic catalysts is a continuous challenge. In this work, covalently linked hybrid porphyrin–nanodiamonds were prepared via ipso nitro substitution reaction and characterized by X-ray photoelectron spectroscopy (XPS), fluorescence spectroscopy, infrared spectroscopy (IR) and thermogravimetry-differential scanning calorimetry (TG-DSC). The amine-functionalized nanodiamonds (ND@NH2 ) and 2-nitro-5,10,15,20-tetra(4-trifluoromethylphenyl)porphyrin covalently linked to nanodiamonds (ND@βNH-TPPpCF3 ) were tested using Allium cepa as a plant model, and showed neither phytotoxicity nor cytotoxicity. The hybrid nanodiamond–copper(II)–porphyrin material ND@βNH-TPPpCF3-Cu(II) was also evaluated as a reusable catalyst in cyclohexene allylic oxidation, and displayed a remarkable turnover number (TON) value of ≈265,000, using O2 as green oxidant, in the total absence of sacrificial additives, which is the highest activity ever reported for said allylic oxidation. Additionally, ND@βNH-TPPpCF3-Cu(II) could be easily separated from the reaction mixture by centrifugation, and reused in three consecutive catalytic cycles without major loss of activity.publishersversionpublishe