Direcção de obra numa empreitada do ramo de hidráulica

Trabalho de Dissertação de natureza científica para obtenção do grau de Mestre em Engenharia Civil do Ramo Hidráulica

Global material analysis on phosphorus flows, supply horizon and impact assessment on phosphorus depletion

Different problems are daily discuss on environmental aspects such acid rain, eutrophication, global warming and an others problems. Rarely do we find some discussions about phosphorus problematic. Through the years the phosphorus as been a real problem and must be more discussed. On this thesis was done a global material flow analysis of phosphorus, based on data from the year 2004, the production of phosphate rock in that year was 18.9 million tones, almost this amount it was used as fertilizer on the soil and the plants only can uptake, on average, 20% of the input of fertilizer to grow up, the remainder is lost for the phosphorus soil. In the phosphorus soil there is equilibrium between the phosphorus available to uptake from the plants and the phosphorus associate with other compounds, this equilibrium depends of the kind of soil and is related with the soil pH. A reserve inventory was done and we have 15,000 million tones as reserve, the amount that is economical available. The reserve base is estimated in 47,000 million tones. The major reserves can be found in Morocco and Western Sahara, United Sates, China and South Africa. The reserve estimated in 2009 was 15,000 million tone of phosphate rock or 1,963 million tone of P. If every year the mined phosphate rock is around 22 Mt/yr (phosphorus production on 2008 USGS 2009), and each year the consumption of phosphorus increases because of the food demand, the reserves of phosphate rock will be finished in about 90 years, or maybe even less. About the value/impact assessment was done a qualitative analysis, if on the future we don’t have more phosphate rock to produce fertilizers, it is expected a drop on the crops yields, each depends of the kind of the soil and the impact on the humans feed and animal production will not be a relevant problem. We can recovery phosphorus from different waste streams such as ploughing crop residues back into the soil, Food processing plants and food retailers, Human and animal excreta, Meat and bone meal, Manure fibre, Sewage sludge and wastewater. Some of these examples are developed in the paper.

Groundwater from infiltration galleries used for small public water supply systems: contamination with pesticides and endocrine disruptors

Infiltration galleries are among the oldest known means used for small public water fountains. Owing to its ancestral origin they are usually associated with high quality water. Thirty-one compounds, including pesticides and estrogens from different chemical families, were analysed in waters from infiltration galleries collected in Alto Douro Demarcated Wine region (North of Portugal). A total of twelve compounds were detected in the water samples. Nine of these compounds are described as presenting evidence or potential evidence of interfering with the hormone system of humans and wildlife. Although concentrations of the target analytes were relatively low, many of them below their limit of quantification, four compounds were above quantification limit and two of them even above the legal limit of 0.1 lg/L: dimethoate (30.38 ng/L), folpet (64.35 ng/L), terbuthylazine-desethyl (22.28 to 292.36 ng/L) and terbuthylazine (22.49 to 369.33 ng/L).

Simulation model for driving dynamics, energy use and power supply

Dissertação para obtenção do grau de Mestre em Engenharia Electrotécnica Ramo de Energia

Control of a power supply with cycling current using different controllers

Fast Field Cycling (FFC) Nuclear Magnetic Resonance (NMR) relaxometers require controlled current sources in order to get accurate flux density with respect to its magnet. The main elements of the proposed solution are a power semiconductor, a DC voltage source and the magnet. The power semiconductor is commanded in order to get a linear control of the flux density. To implement the flux density control, a Hall Effect sensor is used. Furthermore, the dynamic behavior of the current source is analyzed and compared when using a PI controller and a PD2I controller.

Regional governance: strategies and disputes in health region management

OBJECTIVE To analyze the regional governance of the health systemin relation to management strategies and disputes.METHODOLOGICAL PROCEDURES A qualitative study with health managers from 19 municipalities in the health region of Bahia, Northeastern Brazil. Data were drawn from 17 semi-structured interviews of state, regional, and municipal health policymakers and managers; a focus group; observations of the regional interagency committee; and documents in 2012. The political-institutional and the organizational components were analyzed in the light of dialectical hermeneutics.RESULTS The regional interagency committee is the chief regional governance strategy/component and functions as a strategic tool for strengthening governance. It brings together a diversity of members responsible for decision making in the healthcare territories, who need to negotiate the allocation of funding and the distribution of facilities for common use in the region. The high turnover of health secretaries, their lack of autonomy from the local executive decisions, inadequate technical training to exercise their function, and the influence of party politics on decision making stand as obstacles to the regional interagency committee’s permeability to social demands. Funding is insufficient to enable the fulfillment of the officially integrated agreed-upon program or to boost public supply by the system, requiring that public managers procure services from the private market at values higher than the national health service price schedule (Brazilian Unified Health System Table). The study determined that “facilitators” under contract to health departments accelerated access to specialized (diagnostic, therapeutic and/or surgical) services in other municipalities by direct payment to physicians for procedure costs already covered by the Brazilian Unified Health System.CONCLUSIONS The characteristics identified a regionalized system with a conflictive pattern of governance and intermediate institutionalism. The regional interagency committee’s managerial routine needs to incorporate more democratic devices for connecting with educational institutions, devices that are more permeable to social demands relating to regional policy making.

Control of a power supply with cycling current using different controllers

Fast Field Cycling (FFC) Nuclear Magnetic Resonance (NMR) relaxometers require controlled current sources in order to get accurate flux density with respect to its magnet. The main elements of the proposed solution are a power semiconductor, a DC voltage source and the magnet. The power semiconductor is commanded in order to get a linear control of the flux density. To implement the flux density control, a Hall Effect sensor is used. Furthermore, the dynamic behavior of the current source is analyzed and compared when using a PI controller and a PD2I controller.

Supply chain optimization of residual forestry biomass for bioenergy production: the case study of Portugal

Within a large set of renewable energies being explored to tackle energy sourcing problems, bioenergy can represent an attractive solution if effectively managed. The supply chain design supported by mathematical programming can be used as a decision support tool to the successful bioenergy production systems establishment. This strategic decision problem is addressed in this paper where we intent to study the design of the residual forestry biomass to bioelectricity production in the Portuguese context. In order to contribute to attain better solutions a mixed integer linear programming (MILP) model is developed and applied in order to optimize the design and planning of the bioenergy supply chain. While minimizing the total supply chain cost the production energy facilities capacity and location are defined. The model also includes the optimal selection of biomass amounts and sources, the transportation modes selection, and links that must be established for biomass transportation and products delivers to markets. Results illustrate the positive contribution of the mathematical programming approach to achieve viable economic solutions. Sensitivity analysis on the most uncertain parameters was performed: biomass availability, transportation costs, fixed operating costs and investment costs. (C) 2015 Elsevier Ltd. All rights reserved.

Reversible current power supply for fast-field cycling nuclear magnetic resonance equipment

The Fast Field-Cycling Nuclear Magnetic Resonance (FFC-NMR) is a technique used to study the molecular dynamics of different types of materials. The main elements of this equipment are a magnet and its power supply. The magnet used as reference in this work is basically a ferromagnetic core with two sets of coils and an air-gap where the materials' sample is placed. The power supply should supply the magnet being the magnet current controlled in order to perform cycles. One of the technical issues of this type of solution is the compensation of the non-linearities associated to the magnetic characteristic of the magnet and to parasitic magnetic fields. To overcome this problem, this paper describes and discusses a solution for the FFC-NMR power supply based on a four quadrant DC/DC converter.

Empreitada de construção dos armazéns do polo 2 da plataforma logística do porto de Leixões - Direção e controlo da produção

A Plataforma Logística do Porto de Leixões, administrada pela Administração dos Portos do Douro e Leixões, S.A. (APDL), integra dois Polos situados no concelho de Matosinhos em locais estratégicos para o desenvolvimento das atividades portuária e de logística. É neste contexto que a empresa Luís Simões contactou a APDL no sentido de alugar um espaço para se instalar no Polo 2 da Plataforma Logística do Porto de Leixões. Para que este contrato fosse celebrado existiu um compromisso da APDL de construir dois armazéns com cerca de 10.000m2 cada e ainda um edifício administrativo com cerca de 2.900m2 e todas as redes de infraestruturas, circulações e arranjos exteriores. Após a realização de Concurso Público, a Empreitada de Construção, foi adjudicada à empresa DST - Domingos da Silva Teixeira, S.A.. O presente relatório é referente a um estágio realizado na DST, S.A., em obra, no período de 31 de Janeiro de 2014 e 31 de Julho de 2014. O estágio englobou a direção e controlo da produção das atividades de construção civil que decorreram na empreitada durante este período. O estágio foi efetuado em ambiente real de obra tendo seguido o planeamento habitual de uma empreitada. Foram desenvolvidas numa primeira fase as atividades de preparação e lançamento de consultas de subempreitadas. De seguida foram desenvolvidas tarefas de preparação, controlo de fornecimento, apoio e acompanhamento dos subempreiteiros em obra, destacando-se o acompanhamento dos trabalhos de revestimento exteriores dos edifícios e dos pavimentos de alta planimetria.

Experiências supply-siders na UE15: a redução de impostos como política de melhoria da posição orçamental intertemporal

A Curva de Laffer postula que a partir de determinados níveis de taxas de impostos, uma redução destas pode aumentar as receitas fiscais. Tendo presentes os recentes desenvolvimentos da teoria do crescimento económico, que predizem que a política fiscal tem efeitos permanentes de longo prazo na taxa de crescimento económico, aquele argumento pode ser encarado num contexto dinâmico: a fiscalidade afecta permanentemente a taxa de crescimento económico de longo prazo, alterando as bases fiscais futuras, melhorando, em consequência, a posição orçamental de longo prazo. Neste artigo procura-se averiguar a validação de um efeito Laffer dinâmico para os Estados-Membros da União Europeia dos 15 e, em consequência, se a política fiscal pode ser gerida de forma a substituir o endividamento por reduções de impostos.

An information model for lean, agile, resilient and green supply chain management

Dissertação para a obtenção de Grau de Mestre em Engenharia e Gestão Industrial

Rede de Calor – Uma Solução a Biomassa para um Complexo de Hóteis

O recurso às energias renováveis é na actualidade um tema que atinge um grau de importância primordial face á crescente preocupação com o meio ambiente e o impacto negativo, que a produção de energia com base em combustíveis fósseis tem. Esta importância aliada a uma tendência cada vez maior para a criação de soluções de produção sustentável de energia, tem obrigado ao desenvolvimento desta vertente do sector energético e ao estudo e consequentemente implementação de soluções integradas que permitam uma economia competitiva. Os hotéis, sendo estabelecimentos comerciais que desenvolvem uma actividade que envolve, na generalidade, um nível de consumo energético considerável para garantir os seus serviços básicos de acomodação e lazer, tornam-se por excelência alvos primordiais no que concerne ao seu elevado potencial de poupança de energia. O ramo da hotelaria, dada a sua especificidade e a natureza dos edifícios que comporta, torna-os em excelentes candidatos para análise e optimização energética, e como tal um alvo de negócio para as empresas de comercialização de poupanças energéticas. As empresas dedicadas aos serviços de energia são conhecidas por ESCO (Energy Service Company ou Energy Savings Company). A sua actividade tem por base apresentar soluções de energia, nomeadamente a implementação de projectos de poupança energética que podem englobar produção, conservação e fornecimento de energia, bem como gestão de risco associada. O objectivo principal é apresentar soluções de optimização e eficiência energética levando á sua implementação em casos reais de exploração em edifícios ou sectores específicos, rentabilizando o investimento e partilhando o lucro dessa rentabilização com os clientes. No caso específico dos hotéis, mais concretamente um complexo de hotéis, como o estudado neste trabalho, esta análise pretende elaborar uma caracterização das necessidades energéticas do sector e apresentar um conjunto de soluções energéticas adequadas à realidade hoteleira. É também objecto de análise, toda a aproximação de um modelo de negócio energético a explorar por uma ESCO. O presente trabalho, realizado no âmbito da parceria entre a Gebio e a Confraria do Bom Jesus, tem por objectivo demonstrar as bases do contracto de performance entre uma empresa ESCO (Gebio – empresa concessionária do projecto) e um complexo de hotéis (constituído pelo Hotel do Lago, Hotel do Parque e Hotel do Templo), com vista a optimizar os consumos energéticos para a produção de energia térmica capaz de corresponder às necessidades do complexo. Foi desenvolvido um estudo completo das necessidades térmicas do complexo, com vista a projectar uma solução integrada de produção de energia térmica, com recurso a uma caldeira de biomassa, para os hotéis. Foi realizado um levantamento extensivo dos consumos e custos energético do complexo, nomeadamente para as águas quentes sanitárias. Desta análise obtiveram-se os custos reais do sistema e com os mesmos foi possível, numa primeira fase, elaborar os diversos projectos, hidráulico, eléctricos e civil, de forma a se definir a solução base e quais os orçamentos previstos para a instalação de um sistema de produção a biomassa, e numa segunda fase foi estudada a viabilidade da assinatura de um contracto de performance entre a ESCO e o complexo de hotéis.

Prostatic Arterial Supply: Anatomic and Imaging Findings Relevant for Selective Arterial Embolization

PURPOSE: To describe the anatomy and imaging findings of the prostatic arteries (PAs) on multirow-detector pelvic computed tomographic (CT) angiography and digital subtraction angiography (DSA) before embolization for symptomatic benign prostatic hyperplasia (BPH). MATERIALS AND METHODS: In a retrospective study from May 2010 to June 2011, 75 men (150 pelvic sides) underwent pelvic CT angiography and selective pelvic DSA before PA embolization for BPH. Each pelvic side was evaluated regarding the number of independent PAs and their origin, trajectory, termination, and anastomoses with adjacent arteries. RESULTS: A total of 57% of pelvic sides (n = 86) had only one PA, and 43% (n = 64) had two independent PAs identified (mean PA diameter, 1.6 mm ± 0.3). PAs originated from the internal pudendal artery in 34.1% of pelvic sides (n = 73), from a common trunk with the superior vesical artery in 20.1% (n = 43), from the anterior common gluteal-pudendal trunk in 17.8% (n = 38), from the obturator artery in 12.6% (n = 27), and from a common trunk with rectal branches in 8.4% (n = 18). In 57% of pelvic sides (n = 86), anastomoses to adjacent arteries were documented. There were 30 pelvic sides (20%) with accessory pudendal arteries in close relationship with the PAs. No correlations were found between PA diameter and patient age, prostate volume, or prostate-specific antigen values on multivariate analysis with logistic regression. CONCLUSIONS: PAs have highly variable origins between the left and right sides and between patients, and most frequently arise from the internal pudendal artery.

Lean, agile, resilient and green supply chain management interoperability assessment methodology

Dissertação para obtenção de grau de Mestre em Engenharia e Gestão Industrial (MEGI)