27 research outputs found

    A systematic analysis of an industrial pickup and placement production system

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    Surface-mount technology is a method for producing electronic circuits in which the components are mounted or placed directly onto the surface of printed circuit boards. The purpose of this study was to analyze nozzle change in two production lines. Following a previous study, it was proposed that one type of nozzle would place resistors while another type of nozzle would place capacitors, contrary to what happened in the initial process, where the two placed both components. However, the change of nozzle was not done globally, but only applied to two specific types of capacitors that were more critical. Even so, the positive effect of this change was globally visible, both in the decreased number of component rejection and in the reduced number of component defects in the printed circuit boards. It was also possible to estimate the percentage saving and the expected growth from this new implementation. The data were validated using statistical analysis. Finally, the current cleaning periodicity of the nozzles was examined in order to verify if it was compromising their performance.- (undefined

    A novel route to optimize placement equipment kinematics by coupling capacitive accelerometers

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    Machine end-effector kinematic analysis is critical to optimizing transporting components where inertial forces are the main loads. While displacements may be measured with relatively high accuracy in transportation equipment motors, the inertial forces in the transported components are seldom optimized. This is especially relevant in electronic component placement systems, where the components have a wide range of configurations (i.e., geometry and mass) and the deployment dimensional/geometric tolerances are remarkably good. The optimization of these systems requires the monitoring of the real position of the accelerometers relative to the measurement point of interest with sufficient accuracy that allows the assembly position to be predicted instantaneously. This study shows a novel method to calibrate this equipment using triaxial accelerometers on a surface mount machine to measure the end-effector accelerations and velocities in its planar motion. The dynamic equations of the system and the method for integration are presented to address the uncertainty on the exact position of the accelerometer sensors relative to the measuring point of interest exist and allow the position correction to optimize response and accuracy.European Structural and Investment Funds in the FEDER component through the Operational Competitiveness and Internationalization Programme (COMPETE 2020) [Project no. 39479; Funding Reference: POCI-01-0247-FEDER-39479]

    Hydrobia ulvae imposex levels at Ria de Aveiro (NW Portugal) between 1998 and 2007: a counter-current bioindicator?

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    Imposex expression in prosobranch gastropods has been widely used as a biomarker of tributyltin (TBT) pollution. Estuaries have been described as the most affected areas by this problem since they usually enclose the main TBT sources—ports, dockyards and marinas—resulting from the compound’s application as a biocide in antifouling paints on ships. Using Hydrobia ulvae as a bioindicator, the current work addresses the most reliable methods to reduce the influence of critical variables, such as the animals’ size, on imposex levels assessment for TBT pollution monitoring and presents its temporal trends from 1998 to 2007 in Ria de Aveiro (NW Portugal) to evaluate the effectiveness of recent legislation applied to reduce TBT environmental levels. H. ulvae imposex levels did not decrease in this estuarine system during the last decade despite the implementation of the EU Regulation No. 782/2003. Instead, there was a global significant increase in the percentage of females affected by imposex and a slight increase of the vas deferens sequence index (VDSI), contrasting with what has been described for other bioindicators in the same study area. These results show that different biology/ecology traits determine distinct routes of TBT uptake and/or bioaccumulation, pointing the importance of choosing the bioindicator depending on the compartment that is being monitored (sediment vs. water). Sediment ingestion as feeding habit is discussed and pointed as a reason to choose H. ulvae as a bioindicator of TBT pollution persistence in sediment. It is therefore predicted that the response of different prosobranch species around the world may diverge according to the compartment that is being monitored and that female masculinisation may not be completely eradicated in the near future due to TBT persistence in sediments

    A list of land plants of Parque Nacional do Caparaó, Brazil, highlights the presence of sampling gaps within this protected area

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    Brazilian protected areas are essential for plant conservation in the Atlantic Forest domain, one of the 36 global biodiversity hotspots. A major challenge for improving conservation actions is to know the plant richness, protected by these areas. Online databases offer an accessible way to build plant species lists and to provide relevant information about biodiversity. A list of land plants of “Parque Nacional do Caparaó” (PNC) was previously built using online databases and published on the website "Catálogo de Plantas das Unidades de Conservação do Brasil." Here, we provide and discuss additional information about plant species richness, endemism and conservation in the PNC that could not be included in the List. We documented 1,791 species of land plants as occurring in PNC, of which 63 are cited as threatened (CR, EN or VU) by the Brazilian National Red List, seven as data deficient (DD) and five as priorities for conservation. Fifity-one species were possible new ocurrences for ES and MG states

    'Formidável contágio': epidemias, trabalho e recrutamento na Amazônia colonial (1660-1750)

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    Aspergillosis: a limiting factor during recovery of captive magellanic penguins Aspergilose: um fator limitante na reabilitação de pingüins-de-Magalhães

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    The article describes the epidemiology, macroscopic and histological lesions as well as the isolation of Aspergillus flavus and A. fumigatus from Magellanic penguins (Spheniscus magellanicus) during recovery in the Center for Recovery of Marine Animals (CRAM - 32ºS/52ºW), over a period of two years. From January 2004 to December 2005 the Center received 52 Magellanic penguins, and 23% (12/52) died. Necropsies were performed and tissue samples were collected for histological and microbiological examination. From 12 dead animals, aspergillosis was confirmed in five animals, corresponding to 42% of the mortality. Granulomatous nodules were observed mainly on air sacs and lungs. Histologically, septate and branching hyphae, measuring 3-5 µm and PAS positive were found. Two of these cases were caused by A. fumigatus, two other by A. flavus, and in one the diagnostic was established by macroscopic lesions observed in the necropsy without sample collection for fungal isolation and identification. The five aspergillosis cases occurred in the first year of the study, when a disinfection program was not yet established in the CRAM. This paper points out the importance of aspergillosis in the rehabilitation process of captive penguins, and emphasize the necessity of an environmental disinfection on the aspergillosis prevention, mycosis that caused a high rate of mortality of the seabirds found on the Brazilian coast and admitted in the CRAM.<br>O trabalho descreve fatores epidemiológicos, achados de necropsia, histológicos e o isolamento de Aspergillus flavus e A. fumigatus em pingüins-de-Magalhães (Spheniscus magellanicus) em reabilitação no Centro de Recuperação de Animais Marinhos (CRAM - 32ºS/52ºW), durante um período de dois anos. De janeiro de 2004 a dezembro de 2005 foram recebidos no Centro, 52 pingüins-de-Magalhães, dos quais 23% (12/52) morreram. Esses animais foram necropsiados e amostras de tecidos foram coletadas para exame histológico e microbiológico. De 12 animais necropsiados, aspergilose foi diagnosticada em 42% (5/12). Granulomas foram observados principalmente em sacos aéreos e pulmões e hifas septadas, hialinas e dicotômicas em ângulo agudo foram encontradas na histologia. Dois casos foram ocasionados por A. fumigatus, outros dois por A. flavus e em um caso o diagnóstico foi estabelecido pelas lesões macroscópicas observadas na necropsia, sem a coleta de amostra para isolamento e identificação fúngica. Os cinco casos da micose ocorreram no primeiro ano, período em que não havia um programa de desinfecção no Centro. Este trabalho ressalta a importância da aspergilose interferindo no processo de reabilitação de pingüins em cativeiro no CRAM, e enfatiza a necessidade da desinfecção ambiental na prevenção da micose, doença que causa uma alta taxa de mortalidade de aves marinhas encontradas na costa brasileira e encaminhadas ao CRAM

    Impregnation of passion fruit bagasse extract in alginate aerogel microparticles

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    Passion fruit bagasse extract (PFBE) is a rich source of polyphenols, including piceatannol. This work produced alginate (1, 2, 3 wt%) aerogel and investigated the impregnation of gallic acid (GA) and PFBE in alginate aerogel microparticles. The microparticles of ca. 100 μm in diameter were obtained by emulsion-gelation method, submitted to solvent exchange, wet impregnation (WI) and supercritical drying. Alginate aerogels derived from 1 wt% solution led to a higher GA loading and, therefore, this formulation was used to impregnate PFBE. The loading of PFBE, total phenolic, and piceatannol contents based on grams of raw aerogel were 0.62 g, 10.77 mg, and 741.85 μg, respectively, which means a loading efficiency of total phenolics and piceatannol of 47.1% and 34.7%. DSC analysis and X-ray diffraction showed that particles behave as amorphous materials and ORAC assay revealed that impregnated aerogel microparticles presented antioxidant capacity. Alginate aerogel microparticles presented as an appropriated material for drug loading, whereas WI and supercritical drying demonstrated to be useful techniques to load PBBE in aerogels15510601068CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP303063/2018-1Sem informação2016/02007-0; 2017/18883-7; 2015/11932-7; 2017/23670-
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