1,820 research outputs found

    Machine learning methods for quality prediction in thermoplastics injection molding

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    © 2021 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting /republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other worksNowadays, competitiveness is a reality in all industrial fields and the plastic injection industry is not an exception. Due to the complex intrinsic changes that the parameters undergo during the injection process, it is essential to monitor the parameters that influence the quality of the final part to guarantee a superior quality of service provided to customers. Quality requirements impose the development of intelligent systems capable to detect defects in the produced parts. This article presents a first step towards building an intelligent system for classifying the quality of produced parts. The basic approach of this work is machine learning methods (Artificial Neural Networks and Support Vector Machines) and techniques that combine the two previous approaches (ensemble method). These are trained as classifiers to detect conformity or even defect types in parts. The data analyzed were collected at a plastic injection company in Portugal. The results show that these techniques are capable of incorporating the non-linear relationships between the process variables, which allows for a good accuracy ( ˜ 99%) in the identification of defects. Although these techniques present good accuracy, we show that taking into account the history of the last cycles and the use of combined techniques improves even further the performance. The approach presented in this article has a number of potential advantages for online predicting of parts quality in injection molding processes.This work was partially supported by the Spanish State Research Agency through the project CHLOE-GRAPH (PID2020-118649RB-l00) and by FCT—Portuguese Foundation for Science and Technology under project grant UIDB/00308/2020.Postprint (author's final draft

    Data acquisition and monitoring system for legacy injection machines

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    © 2021 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting /republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other worksNowadays, companies must embrace the concept of Digitalization and Industry 4.0 to remain competitive in the market. The reality is that most of them do not have their industrial devices prepared to access their data on a real-time basis. As most companies do not have the possibility to renew all their legacy devices and because these devices are still very productive, a retrofit solution is of high interest. In this work, we propose an affordable procedure that allows data collection and monitoring of older injection machines, as a contribution towards legacy devices integration. The developed system neither requires additional proprietary modules, nor contractual annual fees for different devices, sharing the same interface across different machine manufacturers and also contributing to uniform data collection. Evaluation was carried out in a real shop floor, monitoring the injection parameters for different machine models, validating the effectiveness of the developed system.Peer ReviewedPostprint (author's final draft

    An approach to integrating manufacturing data from legacy Injection Moulding Machines using OPC UA

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    To achieve the ambitions related with the concept of a Smart Factory, manufacturers of new industrial devices have been developing and releasing products capable of integrating themselves into fully-connected environments, with the communication capabilities and advanced specifications required. In these environments, the automatic retrieval of data across the shop floor is a must, allowing the analysis of machine performance for increased production quality and outputs. On most of the recently released industrial devices this machine data is readily available. However, the same is not true when using legacy devices. It is also well established that most SMEs are unable or do not intend to radically replace their industrial devices with this purpose only, since that would imply a high investment, and mainly because many of these legacy machines remain highly productive. That said, there is a need to develop integration methodologies for these legacy industrial devices and provide them with smart factory communication capabilities that make them suitable for the new Smart Factory environments. In this work, an approach is proposed, using as a case study an industrial shop floor, to integrate data from a range of injection moulding machines, from different generations and different models / manufacturers. This equipment diversity renders the automatic interconnection extremely challenging, but is also representative of many existing industrial scenarios. This research will contribute to the development of integration methodologies and, consequently, improve equipment compatibility. To apply these methodologies, information about specific machines within the shop floor was gathered, as well as their communication and I/O capabilities, together with other features deemed relevant. A trend in recently released machines can be identified, revealing a special focus on the use of OPC UA standard, making use of its address space based on the structured Euromap information models. On the other hand, the legacy devices mainly allow outputting a text file to an external storage unit connected to the machine, containing machine and injection cycles related information. Regarding the communication interfaces available, the Ethernet interface reveals to be the most common among the recently acquired machines, while USB is the main interface in older equipment. An experimental solution was developed for the presented case study, which uses the machine's USB interface to access these files at each injection cycle, mapping the acquired data to structured information model variables, according with Euromap specifications, and making it available through an OPC UA server address space. The developed server provides a standardized, interoperable, scalable, and secure approach for data exchange between the injection moulding machines and various OPC UA clients, allowing device monitoring and control during operation, as well as transmitting this data to higher-level management systems, e.g., MES and ERP systems. This solution shows that older legacy devices, available across the shop floors, can be retrofitted and integrated in Smart Factory scenarios, side-by-side with recently released equipment, giving production managers access to information needed to monitor and improve the production process, thus moving towards the Factories of the Future.info:eu-repo/semantics/publishedVersio

    IL-17 triggers the onset of cognitive and synaptic deficits in early stages of Alzheimer’s disease

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    © 2021 The Author(s). This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).Neuroinflammation in patients with Alzheimer's disease (AD) and related mouse models has been recognized for decades, but the contribution of the recently described meningeal immune population to AD pathogenesis remains to be addressed. Here, using the 3xTg-AD model, we report an accumulation of interleukin-17 (IL-17)-producing cells, mostly γδ T cells, in the brain and the meninges of female, but not male, mice, concomitant with the onset of cognitive decline. Critically, IL-17 neutralization into the ventricles is sufficient to prevent short-term memory and synaptic plasticity deficits at early stages of disease. These effects precede blood-brain barrier disruption and amyloid-beta or tau pathology, implying an early involvement of IL-17 in AD pathology. When IL-17 is neutralized at later stages of disease, the onset of short-memory deficits and amyloidosis-related splenomegaly is delayed. Altogether, our data support the idea that cognition relies on a finely regulated balance of "inflammatory" cytokines derived from the meningeal immune system.This work was funded by the Fundação para a Ciência e Tecnologia (IF/00013/2014, LISBOA-01-0145-FEDER-028241, and PTDC/MED-IMU/1988/2020) to J.C.R., Santa Casa da Misericórdia (MB-7-2018) and Fundacão para a Ciência e Tecnologia (PTDC/BIM-MEC/4778/2014 and IF/00105/2012) to L.V.L., and PD/BD/114103/2015 to H.C.B. The ORCIDs for this article are as follows: 0000-0001-8367-3005 (L.V.L.) and 0000-0002-7852-343X (J.C.R.).info:eu-repo/semantics/publishedVersio

    Portuguese recommendations for the use of biological and targeted synthetic diseasemodifying antirheumatic drugs in patients with rheumatoid arthritis – 2020 update

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    Objective: To update the recommendations for the treatment of rheumatoid arthritis (RA) with biological and targeted synthetic disease-modifying antirheumatic drugs (bDMARDs and tsDMARDs), endorsed by the Portuguese Society of Rheumatology (SPR). Methods: These treatment recommendations were formulated by Portuguese rheumatologists taking into account previous recommendations, new literature evidence and consensus opinion. At a national meeting, in a virtual format, three of the ten previous recommendations were re-addressed and discussed after a more focused literature review. A first draft of the updated recommendations was elaborated by a team of SPR rheumatologists from the SPR rheumatoid arthritis study group, GEAR. The resulting document circulated among all SPR rheumatologists for discussion and input. The level of agreement with each of all the recommendations was anonymously voted online by all SPR rheumatologists. Results: These recommendations cover general aspects such as shared decision, treatment objectives, systematic assessment of disease activity and burden and its registry in Reuma.pt. Consensus was also achieved regarding specific aspects such as initiation of bDMARDs and tsDMARDs, assessment of treatment response, switching and definition of persistent remission. Conclusion: These recommendations may be used for guidance of treatment with bDMARDs and tsDMARDs in patients with RA. As more evidence becomes available and more therapies are licensed, these recommendations will be updated.info:eu-repo/semantics/publishedVersio

    High connectivity of the Crocodile Shark between the Atlantic and Southwest Indian Oceans: highlights for conservation

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    Among the various shark species that are captured as bycatch in commercial fishing operations, the group of pelagic sharks is still one of the least studied and known. Within those, the crocodile shark, Pseudocarcharias kamoharai, a small-sized lamnid shark, is occasionally caught by longline vessels in certain regions of the tropical oceans worldwide. However, the population dynamics of this species, as well as the impact of fishing mortality on its stocks, are still unknown, with the crocodile shark currently one of the least studied of all pelagic sharks. Given this, the present study aimed to assess the population structure of P. kamoharai in several regions of the Atlantic and Indian Oceans using genetic molecular markers. The nucleotide composition of the mitochondrial DNA control region of 255 individuals was analyzed, and 31 haplotypes were found, with an estimated diversity Hd = 0.627, and a nucleotide diversity pi = 0.00167. An analysis of molecular variance (AMOVA) revealed a fixation index phi(ST) = -0.01118, representing an absence of population structure among the sampled regions of the Atlantic Ocean, and between the Atlantic and Indian Oceans. These results show a high degree of gene flow between the studied areas, with a single genetic stock and reduced population variability. In panmictic populations, conservation efforts can be concentrated in more restricted areas, being these representative of the total biodiversity of the species. When necessary, this strategy could be applied to the genetic maintenance of P. kamoharai.Foundation for Research Support of the Sao Paulo State - FAPESP [2011/23787-0, 2010/51903-2]; Portuguese Foundation for Science and Technology (FCT) [SFRH/BPD/93936/2013]; Foundation for Research Support of the Sao Paulo State - FAPESP [2011/23787-0, 2010/51903-2]; Portuguese Foundation for Science and Technology (FCT) [SFRH/BPD/93936/2013]info:eu-repo/semantics/publishedVersio

    MAMMALS IN PORTUGAL : A data set of terrestrial, volant, and marine mammal occurrences in P ortugal

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    Mammals are threatened worldwide, with 26% of all species being includedin the IUCN threatened categories. This overall pattern is primarily associatedwith habitat loss or degradation, and human persecution for terrestrial mam-mals, and pollution, open net fishing, climate change, and prey depletion formarine mammals. Mammals play a key role in maintaining ecosystems func-tionality and resilience, and therefore information on their distribution is cru-cial to delineate and support conservation actions. MAMMALS INPORTUGAL is a publicly available data set compiling unpublishedgeoreferenced occurrence records of 92 terrestrial, volant, and marine mam-mals in mainland Portugal and archipelagos of the Azores and Madeira thatincludes 105,026 data entries between 1873 and 2021 (72% of the data occur-ring in 2000 and 2021). The methods used to collect the data were: live obser-vations/captures (43%), sign surveys (35%), camera trapping (16%),bioacoustics surveys (4%) and radiotracking, and inquiries that represent lessthan 1% of the records. The data set includes 13 types of records: (1) burrowsjsoil moundsjtunnel, (2) capture, (3) colony, (4) dead animaljhairjskullsjjaws, (5) genetic confirmation, (6) inquiries, (7) observation of live animal (8),observation in shelters, (9) photo trappingjvideo, (10) predators dietjpelletsjpine cones/nuts, (11) scatjtrackjditch, (12) telemetry and (13) vocalizationjecholocation. The spatial uncertainty of most records ranges between 0 and100 m (76%). Rodentia (n=31,573) has the highest number of records followedby Chiroptera (n=18,857), Carnivora (n=18,594), Lagomorpha (n=17,496),Cetartiodactyla (n=11,568) and Eulipotyphla (n=7008). The data setincludes records of species classified by the IUCN as threatened(e.g.,Oryctolagus cuniculus[n=12,159],Monachus monachus[n=1,512],andLynx pardinus[n=197]). We believe that this data set may stimulate thepublication of other European countries data sets that would certainly contrib-ute to ecology and conservation-related research, and therefore assisting onthe development of more accurate and tailored conservation managementstrategies for each species. There are no copyright restrictions; please cite thisdata paper when the data are used in publications.info:eu-repo/semantics/publishedVersio

    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

    Pervasive gaps in Amazonian ecological research

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    Nationwide access to endovascular treatment for acute ischemic stroke in portugal

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    Publisher Copyright: Copyright Ordem dos M dicos 2021.Introduction: Since the publication of endovascular treatment trials and European Stroke Guidelines, Portugal has re-organized stroke healthcare. The nine centers performing endovascular treatment are not equally distributed within the country, which may lead to differential access to endovascular treatment. Our main aim was to perform a descriptive analysis of the main treatment metrics regarding endovascular treatment in mainland Portugal and its administrative districts. Material and Methods: A retrospective national multicentric cohort study was conducted, including all ischemic stroke patients treated with endovascular treatment in mainland Portugal over two years (July 2015 to June 2017). All endovascular treatment centers contributed to an anonymized database. Demographic, stroke-related and procedure-related variables were collected. Crude endovascular treatment rates were calculated per 100 000 inhabitants for mainland Portugal, and each district and endovascular treatment standardized ratios (indirect age-sex standardization) were also calculated. Patient time metrics were computed as the median time between stroke onset, first-door, and puncture. Results: A total of 1625 endovascular treatment procedures were registered. The endovascular treatment rate was 8.27/100 000 inhabitants/year. We found regional heterogeneity in endovascular treatment rates (1.58 to 16.53/100 000/year), with higher rates in districts closer to endovascular treatment centers. When analyzed by district, the median time from stroke onset to puncture ranged from 212 to 432 minutes, reflecting regional heterogeneity. Discussion: Overall endovascular treatment rates and procedural times in Portugal are comparable to other international registries. We found geographic heterogeneity, with lower endovascular treatment rates and longer onset-to-puncture time in southern and inner regions. Conclusion: The overall national rate of EVT in the first two years after the organization of EVT-capable centers is one of the highest among European countries, however, significant regional disparities were documented. Moreover, stroke-onset-to-first-door times and in-hospital procedural times in the EVT centers were comparable to those reported in the randomized controlled trials performed in high-volume tertiary hospitalspublishersversionpublishe
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