Optimization of wastewater quality in the Sines refinery

In order to address and resolve the wastewater contamination problem of the Sines refinery with the main objective of optimizing the quality of this stream and reducing the costs charged to the refinery, a dynamic mass balance was developed nd implemented for ammonia and polar oil and grease (O&G) contamination in the wastewater circuit. The inadequate routing of sour gas from the sour water stripping unit and the kerosene caustic washing unit, were identified respectively as the major source of ammonia and polar substances present in the industrial wastewater effluent. For the O&G content, a predictive model was developed for the kerosene caustic washing unit, following the Projection to Latent Structures (PLS) approach. Comparison between analytical data for ammonia and polar O&G concentrations in refinery wastewater originating from the Dissolved Air Flotation (DAF) effluent and the model predictions of the dynamic mass balance calculations are in a very good agreement and highlights the dominant impact of the identified streams for the wastewater contamination levels. The ammonia contamination problem was solved by rerouting the sour gas through an existing clogged line with ammonia salts due to a non-insulated line section, while for the O&G a dynamic mass balance was implemented as an online tool, which allows for prevision of possible contamination situations and taking the required preventive actions, and can also serve as a basis for establishing relationships between the O&G contamination in the refinery wastewater with the properties of the refined crude oils and the process operating conditions. The PLS model developed could be of great asset in both optimizing the existing and designing new refinery wastewater treatment units or reuse schemes. In order to find a possible treatment solution for the spent caustic problem, an on-site pilot plant experiments for NaOH recovery from the refinery kerosene caustic washing unit effluent using an alkaline-resistant nanofiltration (NF) polymeric membrane were performed in order to evaluate its applicability for treating these highly alkaline and contaminated streams. For a constant operating pressure and temperature and adequate operating conditions, 99.9% of oil and grease rejection and 97.7% of chemical oxygen demand (COD) rejection were observed. No noticeable membrane fouling or flux decrease were registered until a volume concentration factor of 3. These results allow for NF permeate reuse instead of fresh caustic and for significant reduction of the wastewater contamination, which can result in savings of 1.5 M€ per year at the current prices for the largest Portuguese oil refinery. The capital investments needed for implementation of the required NF membrane system are less than 10% of those associated with the traditional wet air oxidation solution of the spent caustic problem. The operating costs are very similar, but can be less than half if reusing the NF concentrate in refinery pH control applications. The payback period was estimated to be 1.1 years. Overall, the pilot plant experimental results obtained and the process economic evaluation data indicate a very competitive solution through the proposed NF treatment process, which represents a highly promising alternative to conventional and existing spent caustic treatment units.

Analysis of a controversial decision process: the case of the pumped hydro storage power plant Atdorf in Germany

Based on the report for the unit “Métodos Interactivos de Participação e Decisão A” (Interactive methods of participation and decision A), coordinated by Prof. Lia Maldonado Teles de Vasconcelos and Prof. Nuno Miguel Ribeiro Videira Costa. This unit was provided for the PhD Program in Technology Assessment in 2015/2016.

Therapeutics bioconjugates: evaluation of iminoboronates as payload delivery system for cancer

The advent of bioconjugation impacted deeply the world of sciences and technology. New biomolecules were found, biological processes were understood, and novel methodologies were formed due to the fast expansion of this area. The possibility of creating new effective therapies for diseases like cancer is one of big applications of this now big area of study. Off target toxicity was always the problem of potent small molecules with high activity towards specific tumour targets. However, chemotherapy is now selective due to powerful linkers that connect targeting molecules with affinity to interesting biological receptors and cytotoxic drugs. This linkers must have very specific properties, such as high stability in plasma, no toxicity, no interference with ligand affinity nor drug potency, and at the same time, be able to lyse once inside the target molecule to release the therapeutic warhead. Bipolar environments between tumour intracellular and extracellular medias are usually exploited by this linkers in order to complete this goal. The work done in this thesis explores a new model for that same task, specific cancer drug delivery. Iminoboronates were studied due to its remarkable selective stability towards a wide pH range and endogenous molecules. A fluorescence probe was design to validate this model by creating an Off/On system and determine the payload release location in situ. A process was optimized to synthetize the probe 8-(1-aminoethyl)-7-hydroxy-coumarin (1) through a reductive amination reaction in a microwave reactor with 61 % yield. A method to conjugate this probe to ABBA was also optimized, obtaining the iminoboronate in good yields in mild conditions. The iminoboronate model was studied regarding its stability in several simulated biological environments and each half-life time was determined, showing the conjugate is stable most of the cases except in tumour intracellular systems. The construction of folate-ABBA-coumarin bioconjugate have been made to complete this evaluation. The ability to be uptaken by a cancer cell through endocytosis process and the conjugation delivery of coumarin fluorescence payload are two features to hope for in this construct.

Professores realistas: mais eficazes e otimistas

A indisciplina na sala de aula prejudica o ensino e a aprendizagem sendo uma das principais causas do mal-estar dos professores, roubando-lhes energia e tempo conduzindo, muitos deles, à exaustão física e emocional e apresenta-se como um sério problema quer para professores principiantes, quer para professores experientes. A análise do ensino na perspetiva interpessoal possibilita uma nova visão sobre o ambiente de aprendizagem, nomeadamente no que se refere à relação professor-aluno. Nesta perspetiva, o enfoque dirige-se para a análise das perceções dos alunos sobre o comportamento do professor e o impacto que o mesmo tem sobre os alunos. Além de que, ao considerar-se a turma como um sistema deve ter-se em conta que o comportamento não pode ser visto como uma característica da pessoa mas, sim, como uma característica do sistema formado por aqueles que estão envolvidos na interação comunicacional. Analisar as interações comunicacionais à luz da pragmática da comunicação e dos seus cinco axiomas apresenta-se como um poderoso quadro clarificador de muitos dos comportamentos ditos disruptivos, possibilitando aos professores um “novo olhar” sobre o seu papel enquanto gestores da sala de aula. A formação realista de professores apresenta-se como uma estratégia com efeitos muito positivos uma vez que possibilita e ajuda-os a compreenderem o processo de circularidade característico da turma vista como um sistema. Por outro lado, permite evidenciar a impossibilidade dos professores de solucionarem os problemas disciplinares culpabilizando os alunos. Dito de outro modo, a formação realista conduz os professores a um (re) equacionar das suas práticas encorajando-os a selecionarem um comportamento interpessoal mais adequado. No 1º e 3º período letivo, os professores participantes (N= 15) responderam ao Questionário de Interação do Professor (Q.I.P.) e ao Questionário do Otimismo Académico (Q.O.A.) composto por três subescalas: Autoeficácia, Confiança nos alunos e famílias e Ênfase académica. Paralelamente, foram gravadas em suporte vídeo quatro aulas de cada professor, referentes a duas turmas selecionadas previamente pelos mesmos. Após a observação das suas aulas refletiram por escrito aquilo que observaram. No 2º período, participaram numa ação de formação intitulada “Ecologia da sala de aula: relacionamento interpessoal professor-aluno e a criação de ambientes de aprendizagem positivos” baseada no modelo realista de formação de professores. Desta formação resultou um conjunto de relatórios reflexivos que tiveram por objetivo desenvolver nos participantes a sua competência reflexiva, questionarem crenças tidas como inquestionáveis e otimizar a relação professor-aluno. A partir dos resultados obtidos pode afirmar-se que: 1) verificou-se um aumento no otimismo académico e no sentimento de autoeficácia; 2) observou-se um impacto nas conceções prévias, bem como no contexto organizacional.

Design of a case-based reasoner for information security in military organizations

Information security is concerned with the protection of information, which can be stored, processed or transmitted within critical information systems of the organizations, against loss of confidentiality, integrity or availability. Protection measures to prevent these problems result through the implementation of controls at several dimensions: technical, administrative or physical. A vital objective for military organizations is to ensure superiority in contexts of information warfare and competitive intelligence. Therefore, the problem of information security in military organizations has been a topic of intensive work at both national and transnational levels, and extensive conceptual and standardization work is being produced. A current effort is therefore to develop automated decision support systems to assist military decision makers, at different levels in the command chain, to provide suitable control measures that can effectively deal with potential attacks and, at the same time, prevent, detect and contain vulnerabilities targeted at their information systems. The concept and processes of the Case-Based Reasoning (CBR) methodology outstandingly resembles classical military processes and doctrine, in particular the analysis of “lessons learned” and definition of “modes of action”. Therefore, the present paper addresses the modeling and design of a CBR system with two key objectives: to support an effective response in context of information security for military organizations; to allow for scenario planning and analysis for training and auditing processes.

Impact of an occupational gym program on flexibility in office workers

The problem of work-related musculoskeletal disorders is a rising concern in the companies. Thus, occupational gym has emerged as a possible solution to this problem because it leads to changes in the lifestyle by promoting health and physical activity. In this regard, this study purposes to evaluate the impact of an occupational gym program in the neck and shoulder flexibility in office workers. In order to evaluate the levels of flexibility, a universal goniometer was used for pre and post occupational gym program implementation. The program had an extension of three months, with 15 minutes sessions twice a week. The sample consisted in an intervention group comprised of 30 elements and a control group composed of 8 elements. The results suggest that there were improvements in flexibility at the cervical spine and shoulder segments levels. The increase on flexibility between the two time points in the intervention group was significant, unlike the control group that presented only slight improvements.

Strategic planning of electricity systems: Integrating renewable energies

Tese de Doutoramento - Programa Doutoral em Engenharia Industrial e Sistemas (PDEIS)

Fuzzy maintenance costs of a wind turbine pitch control device

This paper deals with the problem of estimation maintenance costs for the case of the pitch controls system of wind farms turbines. Previous investigations have estimated these costs as (traditional) “crisp” values, simply ignoring the uncertainty nature of data and information available. This paper purposes an extended version of the estimation model by making use of the Fuzzy Set Theory. The results alert decision-makers to consequent uncertainty of the estimations along with their overall level, thus improving the information given to the mainte-nance support system.

Global vs. local nonlinear optimization techniques for human-like movement of an anthropomorphic robot

In this paper a comparison between using global and local optimization techniques for solving the problem of generating human-like arm and hand movements for an anthropomorphic dual arm robot is made. Although the objective function involved in each optimization problem is convex, there is no evidence that the admissible regions of these problems are convex sets. For the sequence of movements for which the numerical tests were done there were no significant differences between the optimal solutions obtained using the global and the local techniques. This suggests that the optimal solution obtained using the local solver is indeed a global solution.

A new competitive implementation of the electromagnetism-like algorithm for global optimization

The Electromagnetism-like (EM) algorithm is a population- based stochastic global optimization algorithm that uses an attraction- repulsion mechanism to move sample points towards the optimal. In this paper, an implementation of the EM algorithm in the Matlab en- vironment as a useful function for practitioners and for those who want to experiment a new global optimization solver is proposed. A set of benchmark problems are solved in order to evaluate the performance of the implemented method when compared with other stochastic methods available in the Matlab environment. The results con rm that our imple- mentation is a competitive alternative both in term of numerical results and performance. Finally, a case study based on a parameter estimation problem of a biology system shows that the EM implementation could be applied with promising results in the control optimization area.

Girls out of school. State, culture and education in poor rural Lao People's Democratic Republic

Tese de Doutoramento em Sociologia

Evaluation of temperature influence on embedded kinematic system

Dissertação de mestrado integrado em Engenharia Mecânica

Carbon materials as new generation of new electron shuttles for the anaerobic degradation of environmental xenobiotics

Tese de Doutoramento em Engenharia Química e Biológica

Development of a model for occupational risk acceptance criteria definition in industrial settings

Doctoral Dissertation for PhD degree in Industrial and Systems Engineering

Construction of an innocuous Salmonella phage

Dissertação de mestrado em Bioengenharia