12 resultados para observatory of industrial activities

em Repositório Científico do Instituto Politécnico de Lisboa - Portugal


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Workflows have been successfully applied to express the decomposition of complex scientific applications. However the existing tools still lack adequate support to important aspects namely, decoupling the enactment engine from tasks specification, decentralizing the control of workflow activities allowing their tasks to run in distributed infrastructures, and supporting dynamic workflow reconfigurations. We present the AWARD (Autonomic Workflow Activities Reconfigurable and Dynamic) model of computation, based on Process Networks, where the workflow activities (AWA) are autonomic processes with independent control that can run in parallel on distributed infrastructures. Each AWA executes a task developed as a Java class with a generic interface allowing end-users to code their applications without low-level details. The data-driven coordination of AWA interactions is based on a shared tuple space that also enables dynamic workflow reconfiguration. For evaluation we describe experimental results of AWARD workflow executions in several application scenarios, mapped to the Amazon (Elastic Computing EC2) Cloud.

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This paper describes preliminary work done towards the development of new metallic heterogeneous catalysts to be used in the transesterification reaction of triglycerides, which is of considerable interest in the production of biodiesel. Biodiesel, is a mixture of mono-alkyl esters of fatty acids, and is currently manufactured by transesterification of triglycerides with methanol using NaOH or KOH as liquid base catalyst. Catalysts as such are corrosive to the equipment, and as these catalysts are in liquid phase must be neutralized after the completion of the reaction, typically using HCl, thus producing salt streams. Moreover, due to the presence of free fatty acids it reacts to form soaps as unwanted by-products, hence requiring more expensive separation processes. Therefore, there is a great need on the development of industrial processes for biodiesel production using solid acid catalysts. The key benefit of using solid acid catalysts is that no polluting by-products are formed and the catalysts do not have to be removed since they do not mix with the biodiesel product.

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The study’s main purpose was the assessment of the environmental fungal contamination, the exploration of possible associations between related environmental variables and the study of the relationship between fungal contamination of air and surfaces. A descriptive study was developed based upon air and surfaces monitoring for fungal contamination in ten indoor gymnasiums with a swimming pool located in Lisbon’s urban area. Fifty 200 litres air samples and 120 surface swabs were collected. Surfaces samples were collected before and after cleaning and disinfection and temperature and relative humidity values were registered during the collection period. Twenty five different species of fungi were identified in the air samples, being the three most commonly isolated genera the following: Cladosporium (36.6%), Penicillium (19.0%) and Aspergillus (10.2%). Thirty-seven different species of fungi were identified in the surface samples. Fusarium sp. was the most frequent genera before (19.1%) and after (17.2%) cleaning and disinfection. There was a significant association between the numbers of visitors and the fungal contamination determined in the surface samples (p<0.05). There was no significant association (p>0.05) between the contamination encountered in the air samples and the one registered in the surface samples and between the fungal contamination and the temperature or relative humidity measured on location. The data obtained enabled the assessment of the establishment’s fungal contamination and led the authors to conclude, consequently, that physical activity, which generally promotes health, can in fact be challenged by this factor.

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A presente tese teve por base a identificação e resolução de um problema existente no tratamento de efluentes provenientes dos processos de tratamento de superfícies por galvanoplastia, na OGMA – Indústria Aeronáutica de Portugal S.A.. Observou-se a ocorrência, esporádica, de crómio hexavalente, (Cr (VI)), em valor superior ao valor limite de emissão (VLE). Os resultados foram monitorizados e os dados recolhidos no decorrer da actividade de tratamento de efluentes, durante o período de, aproximadamente, 5 anos (2006 a 2011). A recolha de resultados decorreu no âmbito da actividade profissional da mestranda, que, para além da responsabilidade técnica dos processos de galvanoplastia na empresa, é também responsável pelo suporte técnico ao processo de tratamento de efluentes resultantes da actividade de tratamento de superficies por processos de galvanoplastia. A empresa OGMA – Indústria Aeronáutica de Portugal S.A., é uma empresa de actividade aeronáutica dedicada à Fabricação e Manutenção de aeronaves, nomeadamente a prestação de serviços de Manutenção, Revisão e Modernização de, Aeronaves, Motores e Componentes, bem como Fabricação e Montagem de Aeroestruturas. Integrada na OGMA, S.A. encontra-se a área de tratamentos electroquímicos, onde são realizados processos de tratamento de materiais metálicos por electrodeposição, deposição química e conversão química. Desta actividade resulta uma quantidade considerável de efluentes líquidos que necessitam de tratamento adequado previamente à sua descarga em cursos de água. Devido ao tipo de contaminantes que estes efluentes possuem, o tratamento dos mesmos é realizado em várias etapas, passando pela oxidação de cianetos, a redução de cromatos e a neutralização. Posteriormente segue-se uma sedimentação e a remoção de lamas. De modo a garantir um controlo dos parâmetros de descarga dos efluentes tratados, de acordo com a legislação ambiental em vigor, o efluente obtido é analisado periodicamente em laboratório acreditado. Na perspectiva de solucionar o problema em questão, procedeu-se à realização de ensaios experimentais utilizando os efluentes provenientes dos tanques de reacção da redução de cromatos e da oxidação de cianetos da linha com cádmio, com especial incidência na variação dos intervalos de pH recomendados para cada uma das fases do tratamento de efluentes, e observação do comportamento das misturas em termos de presença de Cr (VI), quando sujeitos a variações de pH. Após análise dos dados disponíveis e realização de todos os ensaios, conclui-se que, o processo de oxidação de cianeto da linha com cádmio e o processo de redução de cromatos na mesma linha estão a funcionar adequadamente. Concluiu-se que o reaparecimento de Cr (VI) ocorre devido à existência de hipoclorito de sódio, em excesso, no tanque de oxidação de cianeto que, quando passa para o tanque de neutralização e entra em contacto com o efluente proveniente do tanque de redução de cromatos, oxida parte do crómio trivalente, (Cr (III)), existente, a Cr (VI). Para impedir a ocorrência deste fenómeno separou-se todo o efluente contendo crómio que passou a ser tratado na linha de tratamento de efluentes isenta de cádmio, não entrando assim em contacto com o efluente que contém hipoclorito não reagido, evitando a oxidação do Cr (III) a Cr (VI).

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A preocupação sobre a qualidade do ar nas zonas industriais confere aos estudos sobre a qualidade do ar uma importância acrescida. Este trabalho teve como objectivo saber qual a contribuição dos principais poluentes provenientes do tráfego automóvel para a qualidade do ar na zona do parque industrial da Sapec, da Península da Mitrena, concelho de Setúbal, recorrendo ao modelo meteorológico e de qualidade do ar, TAPM (The Air Pollution Model). Neste trabalho analisaram-se dados da estação de monitorização da qualidade do ar, mais próxima da zona de estudo (Subestação) por forma a caracterizar-se a zona em causa, a nível meteorológico e da qualidade do ar. Os dados metereológico desta estação também foram utilizados com o objectivo de se validar os resultados meteorológicos obtidos pelo modelo. Na avaliação da contribuição do tráfego para a qualidade do ar, recorreu-se a um estudo de tráfego realizado pela Estradas de Portugal (EP) em 2004. Este estudo realizou a contagem dos veículos que se dirigiram ao parque industrial nos dias 14 e 15 de Dezembro, num período de 24 horas. A partir dessa contagem e de factores de emissão foi possível determinar a contribuição, de cada classe de veículo, para as concentrações atmosféricas de PM10 (resultantes de processos de combustão e ressuspensão), NOx, CO e HC. A comparação entre os dados meteorológicos simulados e medidos mostram que o modelo teve um bom comportamento, isto é, as discrepâncias entre os valores simulados e medidos foram mínimas. Relativamente à contribuição de cada categoria de veículos para a qualidade do ar, verificou-se que a classe de pesados de mercadorias foi aquela que mais contribui para as emissões de PM10, NOx e HC, enquanto que para as emissões de CO foram os veículos ligeiros de passageiros que tiveram uma maior contribuição. As classes dos motociclos e ciclomotores foram aquelas que tiveram uma menor contribuição para as concentrações atmosféricas de poluentes. Comparando as emissões de PM10 provenientes dos processos de combustão e de ressuspensão conclui-se que a maior percentagem provem da ressuspensão.

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This work addresses the treatment by nanofiltration (NF) of solutions containing NaCN and NH(4)Cl at various pH values. The NF experiments are carried out in a Lab-Unit equipped with NF-270 membranes for model solutions that are surrogates of industrial ammoniacal wastewaters generated in the coke-making processes. The applied pressure is 30 bar. The main objective is the separation of the compounds NaCN and NH(4)Cl and the optimization of this separation as a function of the pH. Membrane performance is highly dependent on solution composition and characteristics, namely on the pH. In fact, the rejection coefficients for the binary model solution containing sodium cyanide are always higher than the rejections coefficients for the ammonium chloride model solution. For ternary solutions (cyanide/ammonium/water) it was observed that for pH values lower than 9 the rejection coefficients to ammonium are well above the ones observed for the cyanides, but for pH values higher than 9.5 there is a drastic decrease in the ammonium rejection coefficients with the increase of the pH. These results take into account the changes that occur in solution, namely, the solute species that are predominant, with the increase of the pH. The fluxes of the model solutions decreased with increased pH. (C) 2010 Elsevier B.V. All rights reserved.

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Coumarin and derivates (coumarins) are phenolic compounds widely distributed in the plant kingdom, as for example in tonka beam and cassia cinnamon. These compounds are involved in various processes such as the defense against phytopathogens, the response to abiotic stress and the regulation of oxidative stress. Coumarins can be produced synthetically and are broadly used as additives in the food, perfumes and cosmetics and pharmaceutical industry due th their vast array of biological activities, including anticoagulant, analgesic, anti-inflammatory and anti-microbial.

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Water covers over 70% of the Earth's surface, and is vital for all known forms of life. But only 3% of the Earth's water is fresh water, and less than 0.3% of all freshwater is in rivers, lakes, reservoirs and the atmosphere. However, rivers and lakes are an important part of fresh surface water, amounting to about 89%. In this Master Thesis dissertation, the focus is on three types of water bodies – rivers, lakes and reservoirs, and their water quality issues in Asian countries. The surface water quality in a region is largely determined both by the natural processes such as climate or geographic conditions, and the anthropogenic influences such as industrial and agricultural activities or land use conversion. The quality of the water can be affected by pollutants discharge from a specific point through a sewer pipe and also by extensive drainage from agriculture/urban areas and within basin. Hence, water pollutant sources can be divided into two categories: Point source pollution and Non-point source (NPS) pollution. Seasonal variations in precipitation and surface run-off have a strong effect on river discharge and the concentration of pollutants in water bodies. For example, in the rainy season, heavy and persistent rain wash off the ground, the runoff flow increases and may contain various kinds of pollutants and, eventually, enters the water bodies. In some cases, especially in confined water bodies, the quality may be positive related with rainfall in the wet season, because this confined type of fresh water systems allows high dilution of pollutants, decreasing their possible impacts. During the dry season, the quality of water is largely related to industrialization and urbanization pollution. The aim of this study is to identify the most common water quality problems in Asian countries and to enumerate and analyze the methodologies used for assessment of water quality conditions of both rivers and confined water bodies (lakes and reservoirs). Based on the evaluation of a sample of 57 papers, dated between 2000 and 2012, it was found that over the past decade, the water quality of rivers, lakes, and reservoirs in developing countries is being degraded. Water pollution and destruction of aquatic ecosystems have caused massive damage to the functions and integrity of water resources. The most widespread NPS in Asian countries and those which have the greatest spatial impacts are urban runoff and agriculture. Locally, mine waste runoff and rice paddy are serious NPS problems. The most relevant point pollution sources are the effluents from factories, sewage treatment plant, and public or household facilities. It was found that the most used methodology was unquestionably the monitoring activity, used in 49 of analyzed studies, accounting for 86%. Sometimes, data from historical databases were used as well. It can be seen that taking samples from the water body and then carry on laboratory work (chemical analyses) is important because it can give an understanding of the water quality. 6 papers (11%) used a method that combined monitoring data and modeling. 6 papers (11%) just applied a model to estimate the quality of water. Modeling is a useful resource when there is limited budget since some models are of free download and use. In particular, several of used models come from the U.S.A, but they have their own purposes and features, meaning that a careful application of the models to other countries and a critical discussion of the results are crucial. 5 papers (9%) focus on a method combining monitoring data and statistical analysis. When there is a huge data matrix, the researchers need an efficient way of interpretation of the information which is provided by statistics. 3 papers (5%) used a method combining monitoring data, statistical analysis and modeling. These different methods are all valuable to evaluate the water quality. It was also found that the evaluation of water quality was made as well by using other types of sampling different than water itself, and they also provide useful information to understand the condition of the water body. These additional monitoring activities are: Air sampling, sediment sampling, phytoplankton sampling and aquatic animal tissues sampling. Despite considerable progress in developing and applying control regulations to point and NPS pollution, the pollution status of rivers, lakes, and reservoirs in Asian countries is not improving. In fact, this reflects the slow pace of investment in new infrastructure for pollution control and growing population pressures. Water laws or regulations and public involvement in enforcement can play a constructive and indispensable role in environmental protection. In the near future, in order to protect water from further contamination, rapid action is highly needed to control the various kinds of effluents in one region. Environmental remediation and treatment of industrial effluent and municipal wastewaters is essential. It is also important to prevent the direct input of agricultural and mine site runoff. Finally, stricter environmental regulation for water quality is required to support protection and management strategies. It would have been possible to get further information based in the 57 sample of papers. For instance, it would have been interesting to compare the level of concentrations of some pollutants in the diferente Asian countries. However the limit of three months duration for this study prevented further work to take place. In spite of this, the study objectives were achieved: the work provided an overview of the most relevant water quality problems in rivers, lakes and reservoirs in Asian countries, and also listed and analyzed the most common methodologies.

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Workflows have been successfully applied to express the decomposition of complex scientific applications. This has motivated many initiatives that have been developing scientific workflow tools. However the existing tools still lack adequate support to important aspects namely, decoupling the enactment engine from workflow tasks specification, decentralizing the control of workflow activities, and allowing their tasks to run autonomous in distributed infrastructures, for instance on Clouds. Furthermore many workflow tools only support the execution of Direct Acyclic Graphs (DAG) without the concept of iterations, where activities are executed millions of iterations during long periods of time and supporting dynamic workflow reconfigurations after certain iteration. We present the AWARD (Autonomic Workflow Activities Reconfigurable and Dynamic) model of computation, based on the Process Networks model, where the workflow activities (AWA) are autonomic processes with independent control that can run in parallel on distributed infrastructures, e. g. on Clouds. Each AWA executes a Task developed as a Java class that implements a generic interface allowing end-users to code their applications without concerns for low-level details. The data-driven coordination of AWA interactions is based on a shared tuple space that also enables support to dynamic workflow reconfiguration and monitoring of the execution of workflows. We describe how AWARD supports dynamic reconfiguration and discuss typical workflow reconfiguration scenarios. For evaluation we describe experimental results of AWARD workflow executions in several application scenarios, mapped to a small dedicated cluster and the Amazon (Elastic Computing EC2) Cloud.

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Trabalho Final de Mestrado para obtenção do grau de Mestre em Engenharia de Manutenção

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The aim of this study is to evaluate lighting conditions and speleologists’ visual performance using optical filters when exposed to the lighting conditions of cave environments. A crosssectional study was conducted. Twenty-three speleologists were submitted to an evaluation of visual function in a clinical lab. An examination of visual acuity, contrast sensitivity, stereoacuity and flashlight illuminance levels was also performed in 16 of the 23 speleologists at two caves deprived of natural lightning. Two organic filters (450 nm and 550 nm) were used to compare visual function with and without filters. The mean age of the speleologists was 40.65 (± 10.93) years. We detected 26.1% participants with visual impairment of which refractive error (17.4%) was the major cause. In the cave environment the majority of the speleologists used a head flashlight with a mean illuminance of 451.0 ± 305.7 lux. Binocular visual acuity (BVA) was -0.05 ± 0.15 LogMAR (20/18). BVA for distance without filter was not statistically different from BVA with 550 nm or 450 nm filters (p = 0.093). Significant improved contrast sensitivity was observed with 450 nm filters for 6 cpd (p = 0.034) and 18 cpd (p = 0.026) spatial frequencies. There were no signs and symptoms of visual pathologies related to cave exposure. Illuminance levels were adequate to the majority of the activities performed. The enhancement in contrast sensitivity with filters could potentially improve tasks related with the activities performed in the cave.

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Master Thesis to obtain the Master degree in Chemical Engineering - Branch Chemical Processes