Controlo de Sistemas Pneumáticos

Neste artigo apresenta-se várias abordagens aos problemas de controlo de sistemas industriais tendo como base de atuação a pneumática. São apresentadas as metodologias de controlo de sistemas pneumáticos mais correntes como sejam o método de Cascata, de Memórias e dos Mapas de Karnaugh quer ao nível do controlo pneumático quer elétrico. Apresentam-se diversas abordagens de controlo destes mesmos sistemas recorrendo a autómatos programáveis (PLC)

Simulation and Control of a Cyber-Physical System under IEC 61499 Standard

IEC 61499 standard provides an architecture for control systems using function blocks (FB), languages, and semantics. These devices can be interconnected and communicate with each other. Each device contains several resources and algorithms with a communication FB at the end, which can be created, configured, and deleted without affecting other resources. Physical element can be represented by a FB that encapsulates the functionality (data/events, process, return data/events) in a single module that can be reused and combined. This work presents a simplified implementation of a modular control system using a low-cost device. In the prototyping of the application, we use 4diac to control, model and validate the implementation of the system on a programmable logic controller. It is proved that this approach can be used to model and simulate a cyber-physical system as a single element or in a networked combination. The control models provide a reusable FB design.We acknowledge the financial support of CIDEM, R&D unit funded by FCT – Portuguese Foundation for the Development of Science and Technology, Ministry of Science, Technology and Higher Education, under the Project UID/EMS/0615/2019, and it was supported by FCT, through INEGI and LAETA, under project UIDB/50022/2020.info:eu-repo/semantics/publishedVersio

IEC 61499 REPLICATION FOR FAULT TOLERANT SYSTEM

The IEC 61499 was developed thinking about the new generation of distributed control and automation systems. This provides essential resources for the development of distributed systems such as encapsulation, portability and reconfiguration. In this sense, and to ensure confidence in the operation should be implemented fault tolerance techniques dealing with hardware failures and errors off software associated with us where the distributed application runs. In this paper, we propose an approach to deal with failures in distributed systems tolerance problems, based on a replication model based on replication software/hardware as a means to achieve confidence in the operation.info:eu-repo/semantics/publishedVersio

Reducing Volume to Increase Capacity—Measures to Reduce Transport Energy for Recyclable Waste Collection

The production of municipal waste is increasing all over the world. Although a significant part of the waste is collected as commingled waste, much of it is recyclable if disposed of properly. Thus, separate deposition and collection plays an extremely important role today, more than ever, not only in terms of preventing pollution but also from the point of view of recycling as a driver of circular economy and of efficient use of resources. This work is focused on the development of compaction equipment to be applied to containers, which allows a more efficient approach to the process of collecting waste for recycling. As a management option, recycling depends on collective behavior which is based on individual acts. Therefore, individual use of plastic/metal compaction systems can help meet recycling targets, even as a complement to conventional bins. Thus, herein a proposal is presented for a plastic/metal collection station with a built-in compaction element that allows for the compacting of the separated waste, individually, in an easily accessible drawer. Sorting and compacting waste before collection will result in a reduction of the number of collection/transport stops, which will also translate into higher energy efficiency, cost savings, optimization of the transported tons/km ratio, and profitability.This work was financially supported by Base Funding–UIDB/50022/2020 (LAETA) of INEGI–Institute of Science and Innovation in Mechanical and Industrial Engineering, Portugal, and UIDB/04730/2020 of CIETI–Center for Innovation in Industrial Engineering and Technology, LA/P/0045/2020 (ALiCE), UIDB/00511/2020 and UIDP/00511/2020 (LEPABE), funded by national funds through the FCT/MCTES (PIDDAC), Portugal.info:eu-repo/semantics/publishedVersio

Reliability of Replicated Distributed Control Systems Applications Based on IEC 61499

The use of industrial and domestic equipment is increasingly dependent on computerized control systems. This evolution awakens in the users the feeling of reliability of the equipment, which is not always achieved. However, system designers implement fault-tolerance methodologies and attributes to eliminate faults or any error in the system. Industrially, the increase in system reliability is achieved by the redundancy of control systems based on the replication of conventional and centralized programmable logic controllers. In distributed systems, reliability is achieved by replicating and distributing the most critical elements, leaving a single copy of the remaining components. On the other hand, given the nature of the distributed systems, it will also be necessary to ensure that the data set received by each of the replicas has the same order. Thus, any change in the order and data set received will result in different results, in each of the replicas, which may manifest in erroneous behavior. In this paper, the interactions and the erroneous behavior of the replicas are explained, depending on the data set received, in a fault tolerant distributed system. Its tendency, behavior and possible influences on reliability are presented, considering the failure rate and availability based on the mean time to failure.info:eu-repo/semantics/publishedVersio

A combined approach for comparative exoproteome analysis of Corynebacterium pseudotuberculosis

Background: Bacterial exported proteins represent key components of the host-pathogen interplay. Hence, we sought to implement a combined approach for characterizing the entire exoproteome of the pathogenic bacterium Corynebacterium pseudotuberculosis, the etiological agent of caseous lymphadenitis (CLA) in sheep and goats. Results: An optimized protocol of three-phase partitioning (TPP) was used to obtain the C. pseudotuberculosis exoproteins, and a newly introduced method of data-independent MS acquisition (LC-MSE) was employed for protein identification and label-free quantification. Additionally, the recently developed tool SurfG+ was used for in silico prediction of sub-cellular localization of the identified proteins. In total, 93 different extracellular proteins of C. pseudotuberculosis were identified with high confidence by this strategy; 44 proteins were commonly identified in two different strains, isolated from distinct hosts, then composing a core C. pseudotuberculosis exoproteome. Analysis with the SurfG+ tool showed that more than 75% (70/93) of the identified proteins could be predicted as containing signals for active exportation. Moreover, evidence could be found for probable non-classical export of most of the remaining proteins. Conclusions: Comparative analyses of the exoproteomes of two C. pseudotuberculosis strains, in addition to comparison with other experimentally determined corynebacterial exoproteomes, were helpful to gain novel insights into the contribution of the exported proteins in the virulence of this bacterium. The results presented here compose the most comprehensive coverage of the exoproteome of a corynebacterial species so far

Preliminary Assessment of the Chemical Stability of Dried Extracts from Guazuma ulmifolia Lam. (Sterculiaceae)

We report the results of a preliminary estimation of the stability of the dried extract from bark of Guazuma ulmifolia Lam. (“Mutamba”), with and without added colloidal silicon dioxide (CSD). The physical and chemical properties and the compatibility of CSD in the extract were evaluated for 21 days of storage under stress conditions of temperature (45 ± 2°C) and humidity (75 ± 5%). Thermogravimetry (TG) was supplemented using selective high-performance liquid chromatography (HPLC) for determination of stability of the characteristic constituents (chemical markers), namely, procyanidin B2 (PB2) and epicatechin (EP). The results showed that PB2 is an appropriate compound to be used as a chemical marker in the quality control of dried extracts of G. ulmifolia. The stress study showed that there was no significant difference between the two formulations. However, considering the TG data and the high temperatures involved, the results suggest that CSD increases the stability of the dried extract of G. ulmifolia

Rediscovery of Ruellia reitzii (Acanthaceae), a narrowly endemic critically endangered species from Santa Catarina, southern Brazil, and notes on R. squarrosa

Pesquisa desenvolvida no âmbito do projeto PELD BISC.Ruellia reitzii was first collected in 1948 by the prominent botanist Raulino Reitz in Santa Catarina state, southern Brazil, and the species was only known from two gatherings. Because its most recent collection was in 1953, the species was considered possibly extinct. In this work we present the rediscovery of this species, 65 years after its last collection. Here we complement and rectify the morphologic knowledge of the species, present the first photographs of living specimens and assess its conservation status. We also present notes on the authorship of the name R. squarrosa, and provide an identification key to the species of Ruellia that occur in Santa Catarina.Brazilian Program for Biodiversity Research (PPBio) Atlantic Forest Network [CNPq 457451/2012-9]; CNPq/Capes/FAPs/BC-Fundo Newton/PELD [number 15/ 2016]