Overall equipment effectiveness aplicado às linhas de escolha de uma cerâmica

Mestrado em Engenharia e Gestão IndustrialEste trabalho teve como objetivo principal melhorar a eficácia das linhas de escolha da empresa Pavigrés. Com este trabalho pretendeu-se tomar medidas com base numa monitorização apoiada por indicadores como o Overall Equipment Effectiveness (OEE). Pretendia-se compreender como se processava a escolha do material e ainda identificar as maiores fontes de desperdício que influenciavam o desempenho deste processo. Poderemos ver uma aplicação prática do OEE, em que serão posteriormente apresentados metodologias para o levantamento de dados, resultados obtidos, a análise dos mesmos e as conclusões que se retiraram com esta análise. Para finalizar serão apresentadas algumas sugestões para melhorar a eficácia no setor da escolha da empresa.This thesis aimed to improve the effectiveness of the Pavigrés company's lines of choice. With this work we intended to take action based on a monitoring supported by indicators such as Overall Equipment Effectiveness (OEE). The point was to understand how the choice of material was made and identify the biggest sources of waste that influenced the performance of this process. We may see a practical application of OEE, which will later be presented methodologies for the analysis of results, their analysis and conclusions which withdrew with this analysis. To finish we will present some suggestions to improve effectiveness in the choice’s sector of the company

Conhecimento dos agricultores na utilização dos pesticidas na Zona Centro de Portugal: Impacte na sua saúde

Enquadramento: A realidade que presenciamos atualmente da Saúde dos Agricultores é algo que necessita de atuação emergente. Este grupo profissional encontra-se exposto a uma série de riscos, como os pesticidas, bastante prejudiciais à sua saúde. Objetivos: O estudo tem como finalidade identificar os conhecimentos dos agricultores na utilização dos pesticidas na Zona Centro de Portugal e qual o impacte na sua saúde. Este estudo permitirá (i) identificar as práticas adotadas nas explorações agrícolas, (ii) caracterizar os conhecimentos dos agricultores na utilização dos pesticidas e (iii) conhecer as manifestações clinicas presentes pela utilização de pesticidas. Metodologia: Estudo exploratório realizado com uma amostra não probabilística em bola de neve, constituída por 150 agricultores da zona centro de Portugal. Os participantes apresentavam uma idade mínima de 19 anos e uma máxima de 88 anos, com uma idade média de 53.3 anos (±13.9 anos), sendo 51,3% do género masculino e 48,7 % do género feminino. Para recolha de dados foi aplicado de um questionário estruturado em três partes: caracterização sociodemográfica do inquirido, características da exploração e práticas culturais agrícolas, riscos e saúde (riscos associadas ao uso de pesticidas). Resultados: Dos 150 inquiridos, 116 afirmam usar pesticidas nas suas práticas agrícolas. Em relação aos perigos dos pesticidas, 30% dos agricultores inquiridos referem que estes são muito nocivos e a evitar, contudo 50.7% dos agricultores considera que são nocivos, mas podem-se usar, e 6% considera que os pesticidas são seguros. A salientar que 13.3% consideram que os pesticidas são indispensáveis mesmo que tóxicos. A esmagadora maioria (93.7%) não faz análises aos resíduos dos pesticidas. Conclui-se que 36.7% dos agricultores não usa nenhum equipamento de proteção, e do equipamento mais utilizado sobressaem 51.5% o fato de macaco. As manifestações clínicas mais frequentes, após utilização de pesticidas são dores de cabeça (30.2%) e problemas oculares (37.9%) Conclusões: Nesta perspetiva é de extrema importância uma intervenção por parte dos serviços de saúde neste âmbito, uma vez que também se trata de um problema de Saúde Pública. É necessário que os enfermeiros se envolvam com esta comunidade.Abstract Background: The reality that we are currently witnessing in Farmers' Health is something that needs to emerge. This professional group is exposed to a series of risks, such as pesticides, which are very harmful to their health. Objectives: The objective of this study is to identify farmers' knowledge about the use of pesticides in the Central Zone of Portugal and how they affect their health. This study will (i) identify the practices adopted on farms, (ii) characterize farmers' knowledge of the use of pesticides, and (iii) know the clinical manifestations of pesticide use. Methodology: An exploratory study carried out with a non-probabilistic snowball sample of 150 farmers from central Portugal. Participants had a minimum age of 19 years and a maximum of 88 years, with a mean age of 53.3 years (± 13.9 years), being 51.3% male and 48.7% female. A questionnaire structured in three parts was used to collect data: sociodemographic characterization of the respondent, farm characteristics and agricultural cultural practices, risks and health (risks associated with the use of pesticides and fertilizers). Results: Of the 150 respondents, 116 reported using pesticides in their farming practices. Concerning pesticide hazards, 30% of farmers surveyed report that pesticides are very harmful and should be avoided. However, 50.7% of farmers consider pesticides to be harmful, but they can be used, and 6% consider pesticides to be safe. It should be noted that 13.3% consider pesticides to be indispensable even if toxic. The overwhelming majority (93.7%) do not analyze pesticide residues. It is concluded that 36.7% of the farmers do not use any protective equipment, and the most used equipment stands out 51.5% the fact of monkey. The most frequent clinical manifestations after use of pesticides are headaches (30.2%) and eye problems (37.9%). Conclusions: In this perspective, it is extremely important that health services intervene in this area, since it is also a public health problem. Nurses need to be involved with this community

Influência da gestão e certificação ambiental na sustentabilidade do turismo: caso de estudo do grupo FourViews Hotels

O presente relatório foi realizado para obtenção do grau de mestre em Ecoturismo pela Universidade da Madeira e reflete o meu percurso ao longo de oito meses de estágio na empresa FourViews, um respeitado grupo hoteleiro com base na ilha da Madeira. Nele descrevo as funções que foram desempenhadas por mim no âmbito do estágio do mestrado em Ecoturismo e os respetivos conhecimentos adquiridos, que serão úteis em futura atividade profissional relacionada com a temática deste relatório. Durante o estágio ocupei diversas funções, de modo a ter uma visão mais global que me permitisse compreender como são postas em prática, nos vários departamentos, as medidas ambientais adotadas pelos hotéis do grupo FourViews e, adicionalmente, como surgem os indicadores que demonstram a valia das políticas ambientais. Estes indicadores foram apresentados, comparados e analisados de modo a perceber o impacto que a gestão ambiental e respetiva certificação tiveram nas unidades hoteleiras deste grupo. Este estágio no grupo FourViews, ajudou-me a cimentar a confiança relativamente às mais valias das políticas ambientais, as quais, com trabalho de equipa, dedicação e acreditar, contribuem fortemente para resultados positivos, contribuindo não só a nível ambiental como também financeiro e social.The present report for the Master Degree in Ecotourism from the University of Madeira will expose my work during eight months in the company FourViews, a respected hotel group based in Madeira island. It will describe the tasks I performed regarding environmental management and the knowledge I acquired which may prove useful in a future profession related to this field. During the internship, I worked in different sections of the different hotels, so that I could have a global view of how such an institution functions and where the numbers that prove that environmental policies work come from, as well as how those numbers are achieved. This data will be presented, compared and analysed to identify the impact that environmental management and environmental certification have in the hotels belonging to this group. This internship at the FourViews Group helped me cement my confidence regarding the positive results of environmental policies. I believe these policies, as well as team work and dedication foster good results, not only at an environmental level, but as well at a financial and social

Response of shock interaction patterns to different freestream conditions in carbon-dioxide flows over double-wedges

The shock interaction originating from a hypersonic laminar flow over a double-wedge can lead to different flow patterns depending on geometrical parameters such as the lengths and angles of the each wedge, as well as flow parameters such as the mixture and freestream conditions. In this work, the effect of the freestream Mach number on the patterns of shock interaction is numerically investigated for a CO 2-N 2 nonequilibrium flow over different double-wedge geometries. The numerical analysis is performed by solving the laminar Navier–Stokes equations within the framework of a two-temperature model to account for translational–vibrational internal energy transfer. Results show that the size of separated flow regions, both in the compression corner and locations of shock impingement, increase with decreasing Mach number. This revealed to have a significant impact on the patterns of interaction, since the size of a separation region dictates if additional shocks are generated, potentially leading to more complex mechanisms of interaction. It was concluded that decreasing the freestream Mach number has a similar impact as increasing the angle of the second wedge on the pattern of interaction. The parametric study also shows that decreasing the freestream Mach number leads to overall lower surface pressure and heating, as well as smaller regions of thermal equilibrium

Effect of thermal nonequilibrium on the shock interaction mechanism for carbon dioxide mixtures on double-wedge geometries

The effect of thermal nonequilibrium on shock interactions of carbon dioxide (CO2) hypersonic flows is investigated. Given the relatively low characteristic vibrational temperature of the CO2 molecule, it is expected that excited vibrational modes play a significant role in the physics of shock/shock and shock/boundary layer interactions. The shock interference mechanism resulting from a CO2-dominated flow over different double-wedge geometries is investigated by numerically solving the Navier–Stokes equations within the framework of a two-temperature model that considers translational energy–vibrational energy transfer. To assess the impact of vibrational relaxation, a comparative assessment of the patterns obtained with three thermo-physical models is presented, with the two-temperature model flow pattern being compared to thermally perfect and perfect ideal gas ones. Results obtained with the two-temperature model show that increasing the aft angle significantly enlarges the separated region in the compression corner and generates numerous secondary shock waves and shear layers. Peaks of heat flux and pressure occur along the surface due to boundary layer reattachment downstream of the compression corner, except for the case of the higher angle, which results in the largest peaks due to shock impingement. Different assumptions on the excitation of vibrational modes are shown to largely influence the size of the recirculation bubble in the compression corner, shock interaction mechanism, and surface loads. The more energy transferred to the vibrational mode, the lower post-shock temperatures are obtained, which tends to reduce the post-shock density, leading to weaker shock interactions characterized by delayed onsets of separation, reduced separation regions, and smaller standoff distances

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

Influence of thermochemical modelling of CO2-N2 mixtures on the shock interaction patterns at hypersonic regimes

The effect of finite-rate internal energy transfer on shock interaction mechanisms of CO2-dominated flows is investigated. The polyatomic molecule has a relatively low characteristic vibrational temperature that causes vibrational degrees of freedom to be excited across a shock wave at hypersonic regimes. In this paper, the impact of accounting for the time associated to the relaxation of this process, as opposed to assuming instant thermal equilibrium, on the shock structures occurring in the flowfield over a double-wedge geometry is numerically studied. A Mach 9 flow over two different geometries is simulated with two different models, the two-temperature model of Park and the thermally perfect gas model. Simulations are carried out with the SU2 software that is coupled to the Mutation++ library, providing thermodynamic, chemical kinetic and transport properties of any mixture of gases for a given state of the flow. Anisotropic mesh adaption is used with the AMG library to accurately capture highly directional and high-gradient localized flow features. Results show that different ways of modelling the effect of vibrational relaxation have a major impact on the size of the compression corner separation bubble, leading to different shock wave systems in this region. As a consequence, the obtained shock interaction mechanisms differ as well. The shock patterns obtained for the thermally perfect gas model result in stronger impingement on the surface and higher aerodynamic loads of pressure and heat flux

PEDOT:PSS-coated polybenzimidazole electroconductive nanofibers for biomedical applications

Bioelectricity drives several processes in the human body. The development of new materials that can deliver electrical stimuli is gaining increasing attention in the field of tissue engineering. In this work, novel, highly electrically conductive nanofibers made of poly [2,20 - m-(phenylene)-5,50 -bibenzimidazole] (PBI) have been manufactured by electrospinning and then coated with cross-linked poly (3,4-ethylenedioxythiophene) doped with poly (styrene sulfonic acid) (PEDOT:PSS) by spin coating or dip coating. These scaffolds have been characterized by scanning electron microscopy (SEM) imaging and attenuated total reflectance Fourier-transform infrared (ATR-FTIR) spectroscopy. The electrical conductivity was measured by the four-probe method at values of 28.3 S·m−1 for spin coated fibers and 147 S·m−1 for dip coated samples, which correspond, respectively, to an increase of about 105 and 106 times in relation to the electrical conductivity of PBI fibers. Human bone marrow-derived mesenchymal stromal cells (hBM-MSCs) cultured on the produced scaffolds for one week showed high viability, typical morphology and proliferative capacity, as demonstrated by calcein fluorescence staining, 40 ,6-diamidino-2-phenylindole (DAPI)/Phalloidin staining and MTT [3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide] assay. Therefore, all fiber samples demonstrated biocompatibility. Overall, our findings highlight the great potential of PEDOT:PSS-coated PBI electrospun scaffolds for a wide variety of biomedical applications, including their use as reliable in vitro models to study pathologies and the development of strategies for the regeneration of electroactive tissues or in the design of new electrodes for in vivo electrical stimulation protocols.info:eu-repo/semantics/publishedVersio

Multi-fidelity and multi-disciplinary approach for the accurate simulation of atmospheric re-entry

This paper proposes a multi-fidelity and multi-disciplinary framework that combines low- and high-fidelity aerothermodynamics, thermal analysis, flight dynamics, and structural analysis in a modular approach to achieve a favourable trade-off between cost and accuracy. The novelty in the current study is two-fold: one is to simulate a more accurate destructive re-entry process over using a prescribed altitude trigger for fragmentation, and the other is to implement automatic fidelity switches between high- and low-fidelity models for the aerothermodynamics based on the shock-envelope approximation of Billig's formulation. For the high-fidelity flow modelling, the open-source SU2-NEMO code is used to solve the slip to continuum regimes while the SPARTA-DSMC solver is used for transitional and free-molecular regimes. To estimate the fragmentation altitude, a linear structural analysis of objects modelled as joints are continually carried out using the FEniCS finite elements solver. A temperature-dependent von Mises yield criterion is used to identify failure in joints. The software framework, TITAN Transatmospheric Flight Simulation, is applied to the ESA ATV re-entry and fragmentation test case