Engenheiros portugueses no século XVIII: as suas "geometrias especulativas"

O século XVIII Português foi, à semelhança do resto da Europa, fértil em alterações académicas, científicas e ideológicas. O desenvolvimento da ciência e da técnica, o surgimento das primeiras máquinas, impulsionou a área do saber, que atualmente chamamos de engenharia. Em Portugal (à época ainda um império do qual fazia parte, entre outros, o Brasil), as escolas técnicas e militares consolidam-se e surgem vários engenheiros e militares de renome cujas obras se difundem pelo reino. Manuel de Azevedo Fortes (1660-1749), engenheiro-mor do reino Português, publicou, em 1728 e 1729, os dois tomos de uma das suas obras maiores, O Engenheiro Português, obra dedicada à formação dos engenheiros na Academia Militar de Lisboa.. A primeira parte deste tratado aborda os conhecimentos matemáticos que Azevedo Fortes considera essenciais na formação dos engenheiros. Na sua Geometria Especulativa, um manuscrito datado de 1724, aborda os elementos de geometria e trigonometria, sem esquecer as suas aplicações. O Brigadeiro José Fernandes Pinto Alpoim (1700-1765), engenheiro que se destacou na arquitetura e fortificação do Brasil no século XVIII, publicou o Exame de Artilheiros em 1744 e Exame de Bombeiros em 1748, obras contendo os princípios da geometria e da trigonometria e as suas aplicações à engenharia militar que se destinavam ao ensino dos militares na Academia Militar do Rio de Janeiro, onde era professor. Nesta comunicação analisaremos a matemática, em particular a geometria, presente nestas obras, salientando não só os conteúdos abordados mas a ênfase dada às aplicações desses conteúdos nos contextos militares da época.

Energy harvesting device based on a metallic glass/PVDF magnetoelectric laminated composite

A flexible and low cost energy harvester device based on the magnetoelectric (ME) effect has been designed using Fe64Co17Si7B12 as amorphous magnetostrictive ribbons and PVDF as the piezoelectric element. Sandwich-type laminated composite of 3 cm long has been fabricated by gluing these ribbons to the PVDF with the Devcon 5 minute epoxy. Good power output and power density of 6.4 μW and 1.5 mW/cm3, respectively, have been obtained through a multiplier circuit. All values have been measured at the magnetomechanical resonance of the laminate. The effect of the length of the ME laminate on the power output has been also studied, exhibiting a decay as the length of the ME laminate does. Nevertheless, good performance of such device has been obtained for a 0.5 cm long device, working already at 337 KHz, within the low radio frequency (LRF) range.

Size effects on the magnetoelectric response on PVDF/Vitrovac 4040 laminate composites

Tri-layered and bi-layered magnetoelectric (ME) flexible composite structures of varying geometries and sizes consisting on magnetostrictive Vitrovac and piezoelectric poly(vinylidene fluoride) (PVDF) layers were fabricated by direct bonding. From the ME measurements it was determined that tri-layered composites structures (magnetostrictive-piezoelectric-magnetostrictive type), show a higher ME response (75 V.cm-1.Oe-1) than the bi-layer structure (66 V.cm 1.Oe-1). The ME voltage coefficient decreased with increasing longitudinal size aspect ratio between PVDF and Vitrovac layers (from 1.1 to 4.3), being observed a maximum ME voltage coefficient of 66 V.cm-1.Oe-1. It was also observed that the composite with the lowest transversal aspect ratio between PVDF and Vitrovac layers resulted in better ME performance than the structures with higher transversal size aspect ratios. It was further determined an intimate relation between the Vitrovac PVDF Area Area ratio and the ME response of the composites. When such ratio values approach 1, the ME response is the largest. Additionally the ME output value and magnetic field response was controlled by changing the number of Vitrovac layers, which allows the development of magnetic sensors and energy harvesting devices.

Induced magnetoelectric effect driven by magnetization in BaFe12O19 -/P(VDF-TrFE) composites

Films of BaFe12O19/P(VDF-TrFE) composites with 5, 10 and 20 %wt Barium ferrite content have been fabricated. BaFe12O19 microparticles have the shape of thin hexagonal platelets, the easy direction of magnetization remaining along the c axis, which is perpendicular to the plates. This fact allows for ferrite particles orientation in-plane and out-of-plane within the composite films, as confirmed by measured hysteresis loops. While the in-plane induced magnetoelectric effect (ME) is practically zero, these composite films show a good out-of-plane magnetoelectric effect. with maximum ME coupling coefficient changes of 3, 17 and 2 mV/cm.Oe for the 5, 10 and 20%wt Barium ferrite content films, respectively. We infer that this ME behavior appears as driven by the magnetization process arising when we applied the external magnetic field. We have also measured linear and reversible magnetoelectric effect for low applied bias field, when magnetization process is still reversible.

Optimal behavior of responsive residential demand considering hybrid phase change materials

Due to communication and technology developments, residential consumers are enabled to participate in Demand Response Programs (DRPs), control their consumption and decrease their cost by using Household Energy Management (HEM) systems. On the other hand, capability of energy storage systems to improve the energy efficiency causes that employing Phase Change Materials (PCM) as thermal storage systems to be widely addressed in the building applications. In this paper, an operational model of HEM system considering the incorporation of more than one type of PCM in plastering mortars (hybrid PCM) is proposed not only to minimize the customerâ s cost in different DRPs but also to guaranty the habitantsâ  satisfaction. Moreover, the proposed model ensures the technical and economic limits of batteries and electrical appliances. Different case studies indicate that implementation of hybrid PCM in the buildings can meaningfully affect the operational pattern of HEM systems in different DRPs. The results reveal that the customerâ s electricity cost can be reduced up to 48% by utilizing the proposed model.

A cooperação transfronteiriça como oportunidade de desenvolvimento das regiões de fronteira. Da Raia Ibérica à euroregião Galiza-Norte de Portugal

Tese de Doutoramento em Geografia Humana.

A morte em cuidados intensivos: uma reflexão fenomenológica sobre a experiência dos enfermeiros

Dissertação de mestrado em Enfermagem da Pessoa em Situação Crítica

Pharming: análise dogmático-penal, em especial enquanto forma de lesão do património

Dissertação de mestrado em Direito e Informática

Potencial geopolítico da língua portuguesa para Timor-Leste

Dissertação de mestrado em Relações Internacionais

Por detrás das câmaras: o "directo" e o "gravado"

Dissertação de mestrado em Ciências da Comunicação (área de especialização em Audiovisual e Multimédia)

A comunicação e a imagem do Gabinete de Apoio a Projectos: um estudo de caso

Dissertação de mestrado em Ciências da Comunicação (área de especialização em Publicidade e Relações Públicas)

Desarrollo sustentable de geoestructuras compuestas por suelo loéssico compactado mejorado con agregado de materiales estabilizantes. Sustainable development of compacted loess soil geo-structures with addition of stabilizing materials.

Los suelos estabilizados mediante compactación, permiten obtener materiales con ventajas ténicas y economicas en diferentes tipos de obras de ingeniería. Ejemplos de su uso se tiene en bases viales de autopistas, rutas o calles urbanas, pistas de aterrizaje, barreras de contención para enterramientos sanitarios o lagunas de estabilización, apoyos de plateas para fundación de edificios, losas industriales, entre otras aplicaciones. Las fallas en este tipo de construcciones pueden resultar en catástrofes ambientales, sociales y elevadas pérdidas económicas, por lo que resulta de gran importancia optimizar el diseño e incrementar la seguridad de este tipo de construcciones. Las obras con estas características involucran grandes volúmenes y/o superficies que requieren controles sistemáticos durante su desarrollo, a los fines de garantizar el cumplimiento de las propiedades de los materiales establecidos en la etapa de diseño. De esta forma, es necesario contar con ensayos de campo sencillos, confiables y eficientes que permitan identificar propiedades físicas, mecánicas e hidráulicas. Las geoestructuras generadas mediante la compactación del suelo próximo al sector de construcción pueden funcionar adecuadamente, con reducidos costos de material y transporte. Su estabilización puede ejecutarse en forma natural, o con la incorporación de agregados minerales como bentonita, cal o cemento. Estas incorporaciones mejoran las propiedades hidráulicas y mecánicas del material, optimizando el comportamiento requerido para la obra. Para establecer la forma en la que estos minerales modifican el comportamiento del suelo local compactado deben realizarse investigaciones especiales con los materiales involucrados. En el ámbito internacional existen numerosas investigaciones sobre comportamiento de suelos compactados, no obstante, si bien aportan antecedentes para la planificación de estudios locales, sus resultados no pueden trasladarse de manera directa. Las características propias del suelo local constituye la principal variable debido a la diversidad en las propiedades geotécnicas de cada Región. Esta investigación, se focaliza en el empleo de suelos limosos de la formación loéssica de la zona central de Argentina. Los suelos de la llanura cordobesa poseen comportamientos particulares, los cuales son contemplados en los diseños presentados como resutado de las investigaciones internacionales. Esta particularidad se relaciona con su inestabilidad, lo que los clasifica como suelos colapsables. Los resultados obtenidos en este trabajo podrán ser extendidos a una gran superficie de la Provincia de Córdoba y a la Región Pampeana en general, a los fines de establecer recomendaciones de diseño y construcción para la confección de Pliegos de Especificaciones Técnicas de diferentes tipos de obras públicas y privadas. El estudio contempla la ejecución de un plan experimental a escala de laboratorio y campo. Los materiales corresponden a suelo limosos puros, y diferentes agregados tales como bentonita, cal y cemento. Se planifican ensayos para evaluar el desempeño del material, a partir de la confección de muestras preparadas con diferentes condiciones de compactación (energía, humedad y método), y en forma de mezcla con los distintos tipos de agregados. Se realizarán ensayos de permeabilidad en celdas de pared rígida y flexible, junto a ensayos mecánicos de compresión confinada, simple y triaxial. Para el trabajo experimental de campo se prevé la ejecución de terraplenes de prueba instrumentados con tensiómetros e infiltrómetros para evaluar el comportamiento hidraúlico en el tiempo, junto con ensayos de penetración y plato de carga para la caracterización mecánica. En forma conjunta se propone el desarrollo de modelos numéricos de caracterización hidromecánica. Stabilized soils by compaction, produce materials technical and economic advantages in different types of engineering works. For example, road bases in highways, roads or city streets, containment barriers for sanitary landfill or stabilization ponds, foundation support of building, industrial flat, and other applications. Failures can result in environmental catastrophes, social, and economic loss, so it is important to optimize the design and increase the safety of such buildings. These works involve large surfaces that require systematic tests during construction, so it is necessary to have simple field tests, reliable and efficient to identify physical, mechanical and hydraulic properties. The geo-structures generated by local soil compaction have reduced material and transportation costs. Stabilization can be naturally, or with the addition of mineral aggregates as bentonite, lime and cement. These additions improve the hydraulic and mechanical properties of the material. So, special investigations should be conducted with the materials involved. There are many international studies on compacted soils behavior but their results can not be transferred directly due to the particularities of regional soils. For this research silty soils of central Argentina are the main focus. The soils of Córdoba plains are instability, so are classified as collapsible soils. The results obtained in this work may be extended to a large area of the Province of Cordoba and the Pampas region in general, in order to establish design and construction recommendations. The study includes laboratory and field tests. The materials are pure silty soil, and different aggregates such as bentonite, lime and cement. Tests are planned to evaluate the performance. Laboratory includes rigid and flexible wall cells, confined, triaxial and simple compression tests. For field experimental instrumented embankments will be constructed. A numerical hydromechanical model will be developed.

Erstellung und Lokalisierung von EPUB-Dokumenten

Because of the transformation of the mainstream of information media nowadays, it is vital to constitute a standard of electronic publishing in this emerging field. EPUB is the key standard of the organization IDPF, which is the official standard format for digital books. The present dissertation aims at creating and localizing EPUB documents of the module handbook for the master's degree program software localization at Anhalt University of applied Sciences (Hochschule Anhalt) from German into Chinese as example. This dissertation describes the technical and theoretical foundations of e-book formats and represents especially the structures and features of EPUB. In order to spread the information widely in the world, localization of the products plays an important role. An introduction of localization technology and localization tools is constructed and included in the project. The work processes are mentioned, so as to show, how to translate an EPUB document and ensure good quality. The summary and the view of EPUB are illuminated at the end.

Distribució de revistes científiques en format digital

L'aparició de les revistes en format digital posa de nou de manifest la necessitat de disposar de bons mecanismes de distribució i accés a les mateixes. Això encara esdevé més rellevant en els actuals moments de concentració en grans grups empresarials de l'edició i la distribució de les revistes de l'anomenat àmbit científic, tècnic i mèdic (STM: “scientific, technical and medical”). Davant d'aquest fenomen, encara ho tenen més complicat les publicacions amb una circulació més restringida per raons de llengua o d'especialització. És el cas de moltes revistes publicades a Catalunya, editades i distribuïdes per canals diferents als del sistema STM comercial internacional. Davant d’aquesta problemàtica, el Consorci de Biblioteques Universitàries de Catalunya (CBUC) ha encarregat el present informe. Un dels objectius fonamentals del CBUC és facilitar l'accés dels usuaris a la informació especialitzada; dins d'aquesta es vol prestar un suport especial als continguts creats a Catalunya per tal de facilitar-ne la seva utilització i contribuir al seu desenvolupament futur. Dins l’actual moment de canvi provocat per la irrupció de l’edició digital, es corre el risc de que els continguts catalans no tinguin la suficient presència i utilització en aquest nou suport, cosa que suposaria un evident endarreriment. Per tal d’evitar-ho, el CBUC vol explorar les implicacions i les possibilitats de crear plataformes o portals per a la difusió de les revistes erudites catalanes, en el cas que no ho puguin fer pels canals comercials internacionals. A nivell operatiu aquest informe intenta respondre a les següents preguntes: Què és un portal de revistes científiques?, Quins elements s’han de preveure en la seva constitució?, Quines alternatives de servei hi ha?, Quines problemàtiques tècniques es plantegen? i Existeixen iniciatives o inquietuds semblants a les plantejades pel CBUC?

Geoposicionament per a dispositius mòbils

Aquest projecte té dues parts diferenciades. La primera consisteix en un estudi de la situació actual dels SIG i de les aplicacions que hi treballen. La segona és la planificació, disseny i estudi de viabilitat tant tècnica com econòmica d’un projecte en que el component SIG i la mobilitat tenen un pes determinant.