Combate ao terrorismo em Portugal : Da estratégia à cooperação no quadro das Forças e Serviços de Segurança

A presente investigação, subordinada ao tema “Combate ao Terrorismo em Portugal: da estratégia à cooperação no quadro das Forças e Serviços de Segurança”, tem como objetivo geral compreender de que forma a legislação sobre o combate ao terrorismo e a resposta conjunta e cooperada das forças e serviços de segurança que dela deriva concorrem, atualmente, para o combate desta ameaça em Portugal. A metodologia empregue segue uma matriz dedutiva, focando-se no estudo de caso da Unidade de Coordenação Antiterrorista, e visando, com recurso à análise documental e a inquéritos por entrevista e por questionário, o desenvolvimento de uma cadeia de raciocínio em ordem descendente, de análise do geral para o particular, para chegar a uma conclusão. O estudo compõe-se em três capítulos essenciais, devidamente delineados e interligados pela seguinte sequência lógica: no primeiro (abordagem conceptual), fazemos um breve estudo do terrorismo e do enquadramento legal sobre a temática do combate ao terrorismo; no segundo (enquadramento metodológico), explicamos de forma pormenorizada a metodologia adotada, bem como os métodos e materiais utilizados; e, por fim, no terceiro capítulo (abordagem empírica) procedemos à apresentação, análise e interpretação dos resultados, procurando estabelecer uma ligação entre a vertente legislativa e a vertente operativa do combate ao terrorismo em Portugal. Concluímos que o enquadramento legislativo permite um desenvolvimento eficaz do combate ao terrorismo, ainda que possa ser aprofundado em determinadas áreas. Mas mais do que um quadro legislativo completo, deve haver uma preocupação ao nível da sensibilização das estruturas e dos próprios profissionais das forças e serviços de segurança para a luta contra o fenómeno terrorista, sendo ainda notória alguma precariedade ao nível da partilha de informações e do culto das informações em Portugal, pois só assim conseguiremos que a resposta conjunta e cooperada das forças e serviços de segurança se alinhe com os propósitos estabelecidos pela lei.

Viability of irrigation by porous capsule method in arid and semi-arid regions.

This paper presents the results of four field experiments carried out with the objetive of evaluating the feaibility of irrigation by porous capsule method, from 1979 to 1983, at Bebedouro Experiment Station, EMBRAPA-CPATSA, Petrolina, PE, Brazil. The irrigation system consisted of fulcrum of cone shaped porous capsules, interconnected with conduit pipe and installed in the soil at equidistance and 0.10 m deep along contour lines. The hydrostatic pressures studies did not significantly influence the crop yield, but influenced, at 0.10 level, the daily water release from porous unit. The mean yields for watermelon (Citrullus vulgaris Shard), var. Charleston Gray, for muskmelon (Cucumis melo L.) var. Valenciano Amarelo, and for maize (Zea mays L.), var. Centralmex, estimated in ton/2,500 units/ha or in cobs/2,500 units/ha, were 28.5, 10 and 17,500, respectively. The water consumption for watermelon, musk melon and maize was, respectively, 60 mm, 60 mm and 100 mm in a deep sandy yellow-red latosol. The cost of the system was US$ 1.677,41/ha.

Understanding the CO Preoxidation and the Intrinsic Catalytic Activity of Step Sites in Stepped Pt Surfaces in Acidic Medium

In order to deepen the knowledge about the origin of the CO preoxidation process and the intrinsic catalytic activity of Pt superficial steps toward CO oxidation, a series of CO stripping experiments were performed on stepped Pt electrodes in acidic medium. For the occurrence of CO preoxidation, it was found that it arises (reproducibly) whenever four interconnected conditions are simultaneously fulfilled: (1) CO adsorption at potentials lower than about 0.2 V; (2) on surfaces saturated with COads; (3) in the presence of traces of CO in solution; (4) in the presence of surface steps. If any of these four conditions is not satisfied, the CO preoxidation pathway does not appear, even though the steps on the electrode surface are completely covered by CO. By controlling the removal of the CO adlayer (voltammetrically), we show that once the CO adlayer has been partially oxidized, the (111) terrace sites of stepped surfaces are released earlier than the (110) step sites. Moreover, if (110) steps are selectively decorated with CO, its oxidation occurs only at potentials ∼150 mV higher than the CO preoxidation peak. Our results systematically demonstrate that step sites are less active to oxidize CO than those ones responsible for the CO preoxidation process. Once the sites responsible for the CO preoxidation are made free, there is no apparent motion of the remaining adsorbed CO layer, suggesting that the activation of the surface controls the whole process, rather than the diffusion of COads toward hypothetically “most active sites”. Voltammetric and chronoamperometric experiments performed on partially covered CO adlayers suggest that adsorbed CO behave as a motionless species during its oxidation, in which the CO adlayer is removed piece by piece. By means of in situ FTIR experiments, the stretching frequency of CO selectively adsorbed on (110) step sites was examined. Band frequency results confirm that those molecules adsorbed on steps are fully coupled with the adsorbed CO on (111) terraces when the surface reaches full coverage.

Análise de modelos geológicos utilizando percolação dinâmica

In the present study we elaborated algorithms by using concepts from percolation theory which analyze the connectivity conditions in geological models of petroleum reservoirs. From the petrophysical parameters such as permeability, porosity, transmittivity and others, which may be generated by any statistical process, it is possible to determine the portion of the model with more connected cells, what the interconnected wells are, and the critical path between injector and source wells. This allows to classify the reservoir according to the modeled petrophysical parameters. This also make it possible to determine the percentage of the reservoir to which each well is connected. Generally, the connected regions and the respective minima and/or maxima in the occurrence of the petrophysical parameters studied constitute a good manner to characterize a reservoir volumetrically. Therefore, the algorithms allow to optimize the positioning of wells, offering a preview of the general conditions of the given model s connectivity. The intent is not to evaluate geological models, but to show how to interpret the deposits, how their petrophysical characteristics are spatially distributed, and how the connections between the several parts of the system are resolved, showing their critical paths and backbones. The execution of these algorithms allows us to know the properties of the model s connectivity before the work on reservoir flux simulation is started

Mulheres negras e (in)visibilidade : imaginários sobre a intersecção de raça e gênero no cinema brasileiro (1999-2009)

Tese (doutorado)—Universidade de Brasília, Faculdade de Comunicação, Programa de Pós-Graduação em Comunicação, 2016.

AN ENERGY BASED MINIMUM-TIME OPTIMAL CONTROL OF DC-DC CONVERTERS

Time-optimal response is an important and sometimes necessary characteristic of dynamic systems for specific applications. Power converters are widely used in different electrical systems and their dynamic response will affect the whole system. In many electrical systems like microgrids or voltage regulators which supplies sensitive loads fast dynamic response is a must. Minimum time is the fastest converter to compensate the step output reference or load change. Boost converters as one of the wildly used power converters in the electrical systems are aimed to be controlled in optimal time in this study. Linear controllers are not able to provide the optimal response for a boost converter however they are still useful and functional for other applications like reference tracking or stabilization. To obtain the fastest possible response from boost converters, a nonlinear control approach based on the total energy of the system is studied in this research. Total energy of the system considers as the basis for developing the presented method, since it is easy and accurate to measure besides that the total energy of the system represents the actual operating condition of the boost converter. The detailed model of a boost converter is simulated in MATLAB/Simulink to achieve the time optimal response of the boost converter by applying the developed method. The simulation results confirmed the ability of the presented method to secure the time optimal response of the boost converter under four different scenarios.

REALIZATION OF A DC MICROGRID USING A HAMILTONIAN BASED CONTROLS SOLUTION

Future power grids are envisioned to be serviced by heterogeneous arrangements of renewable energy sources. Due to their stochastic nature, energy storage distribution and management are pivotal in realizing microgrids serviced heavily by renewable energy assets. Identifying the required response characteristics to meet the operational requirements of a power grid are of great importance and must be illuminated in order to discern optimal hardware topologies. Hamiltonian Surface Shaping and Power Flow Control (HSSPFC) presents the tools to identify such characteristics. By using energy storage as actuation within the closed loop controller, the response requirements may be identified while providing a decoupled controller solution. A DC microgrid servicing a fixed RC load through source and bus level storage managed by HSSPFC was realized in hardware. A procedure was developed to calibrate the DC microgrid architecture of this work to the reduced order model used by the HSSPFC law. Storage requirements were examined through simulation and experimental testing. Bandwidth contributions between feed forward and PI components of the HSSPFC law are illuminated and suggest the need for well-known system losses to prevent the need for additional overhead in storage allocations. The following work outlines the steps taken in realizing a DC microgrid and presents design considerations for system calibration and storage requirements per the closed loop controls for future DC microgrids.

Development and Verification of Control and Protection Strategies in Hybrid AC/DC Power Systems for Smart Grid Applications

Modern power networks incorporate communications and information technology infrastructure into the electrical power system to create a smart grid in terms of control and operation. The smart grid enables real-time communication and control between consumers and utility companies allowing suppliers to optimize energy usage based on price preference and system technical issues. The smart grid design aims to provide overall power system monitoring, create protection and control strategies to maintain system performance, stability and security. This dissertation contributed to the development of a unique and novel smart grid test-bed laboratory with integrated monitoring, protection and control systems. This test-bed was used as a platform to test the smart grid operational ideas developed here. The implementation of this system in the real-time software creates an environment for studying, implementing and verifying novel control and protection schemes developed in this dissertation. Phasor measurement techniques were developed using the available Data Acquisition (DAQ) devices in order to monitor all points in the power system in real time. This provides a practical view of system parameter changes, system abnormal conditions and its stability and security information system. These developments provide valuable measurements for technical power system operators in the energy control centers. Phasor Measurement technology is an excellent solution for improving system planning, operation and energy trading in addition to enabling advanced applications in Wide Area Monitoring, Protection and Control (WAMPAC). Moreover, a virtual protection system was developed and implemented in the smart grid laboratory with integrated functionality for wide area applications. Experiments and procedures were developed in the system in order to detect the system abnormal conditions and apply proper remedies to heal the system. A design for DC microgrid was developed to integrate it to the AC system with appropriate control capability. This system represents realistic hybrid AC/DC microgrids connectivity to the AC side to study the use of such architecture in system operation to help remedy system abnormal conditions. In addition, this dissertation explored the challenges and feasibility of the implementation of real-time system analysis features in order to monitor the system security and stability measures. These indices are measured experimentally during the operation of the developed hybrid AC/DC microgrids. Furthermore, a real-time optimal power flow system was implemented to optimally manage the power sharing between AC generators and DC side resources. A study relating to real-time energy management algorithm in hybrid microgrids was performed to evaluate the effects of using energy storage resources and their use in mitigating heavy load impacts on system stability and operational security.

Hybrid Power System Intelligent Operation and Protection Involving Distributed Architectures and Pulsed Loads

Efficient and reliable techniques for power delivery and utilization are needed to account for the increased penetration of renewable energy sources in electric power systems. Such methods are also required for current and future demands of plug-in electric vehicles and high-power electronic loads. Distributed control and optimal power network architectures will lead to viable solutions to the energy management issue with high level of reliability and security. This dissertation is aimed at developing and verifying new techniques for distributed control by deploying DC microgrids, involving distributed renewable generation and energy storage, through the operating AC power system. To achieve the findings of this dissertation, an energy system architecture was developed involving AC and DC networks, both with distributed generations and demands. The various components of the DC microgrid were designed and built including DC-DC converters, voltage source inverters (VSI) and AC-DC rectifiers featuring novel designs developed by the candidate. New control techniques were developed and implemented to maximize the operating range of the power conditioning units used for integrating renewable energy into the DC bus. The control and operation of the DC microgrids in the hybrid AC/DC system involve intelligent energy management. Real-time energy management algorithms were developed and experimentally verified. These algorithms are based on intelligent decision-making elements along with an optimization process. This was aimed at enhancing the overall performance of the power system and mitigating the effect of heavy non-linear loads with variable intensity and duration. The developed algorithms were also used for managing the charging/discharging process of plug-in electric vehicle emulators. The protection of the proposed hybrid AC/DC power system was studied. Fault analysis and protection scheme and coordination, in addition to ideas on how to retrofit currently available protection concepts and devices for AC systems in a DC network, were presented. A study was also conducted on the effect of changing the distribution architecture and distributing the storage assets on the various zones of the network on the system’s dynamic security and stability. A practical shipboard power system was studied as an example of a hybrid AC/DC power system involving pulsed loads. Generally, the proposed hybrid AC/DC power system, besides most of the ideas, controls and algorithms presented in this dissertation, were experimentally verified at the Smart Grid Testbed, Energy Systems Research Laboratory. All the developments in this dissertation were experimentally verified at the Smart Grid Testbed.

Lattice Boltzmann Modeling and Specialized Laboratory Techniques to Determine the Permeability of Megaporous Karst Rock

The Pleistocene carbonate rock Biscayne Aquifer of south Florida contains laterally-extensive bioturbated ooltic zones characterized by interconnected touching-vug megapores that channelize most flow and make the aquifer extremely permeable. Standard petrophysical laboratory techniques may not be capable of accurately measuring such high permeabilities. Instead, innovative procedures that can measure high permeabilities were applied. These fragile rocks cannot easily be cored or cut to shapes convenient for conducting permeability measurements. For the laboratory measurement, a 3D epoxy-resin printed rock core was produced from computed tomography data obtained from an outcrop sample. Permeability measurements were conducted using a viscous fluid to permit easily observable head gradients (~2 cm over 1 m) simultaneously with low Reynolds number flow. For a second permeability measurement, Lattice Boltzmann Method flow simulations were computed on the 3D core renderings. Agreement between the two estimates indicates an accurate permeability was obtained that can be applied to future studies.

Tailored mesoporous silica supports for Ni catalysed hydrogen production from ethanol steam reforming

Mesoporous silica supported Ni nanoparticles have been investigated for hydrogen production from ethanol steam reforming. Ethanol reforming is structure-sensitive over Ni, and also dependent on support mesostructure; three-dimensional KIT-6 possessing interconnected mesopores offers superior metal dispersion, steam reforming activity, and on-stream stability against deactivation compared with a two-dimensional SBA-15 support.

Avoided losses on LV networks as a result of microgeneration

In the scope of the discussions about microgeneration (and microgrids), the avoided electrical losses are often pointed out as an important value to be credited to those entities. Therefore, methods to assess the impact of microgeneration on losses must be developed in order to support the definition of a suitable regulatory framework for the economic integration of microgeneration on distribution networks. This paper presents an analytical method to quantify the value of avoided losses that microgeneration may produce on LV networks. Intervals of expected avoided losses are used to account for the variation of avoided losses due to the number, size and location of microgenerators, as well as for the kind of load distribution on LV networks.

Cognitive and Visual Speech Contributions to Speech Perception in Challenging Listening Conditions

Speech perception routinely takes place in noisy or degraded listening environments, leading to ambiguity in the identity of the speech token. Here, I present one review paper and two experimental papers that highlight cognitive and visual speech contributions to the listening process, particularly in challenging listening environments. First, I survey the literature linking audiometric age-related hearing loss and cognitive decline and review the four proposed causal mechanisms underlying this link. I argue that future research in this area requires greater consideration of the functional overlap between hearing and cognition. I also present an alternative framework for understanding causal relationships between age-related declines in hearing and cognition, with emphasis on the interconnected nature of hearing and cognition and likely contributions from multiple causal mechanisms. I also provide a number of testable hypotheses to examine how impairments in one domain may affect the other. In my first experimental study, I examine the direct contribution of working memory (through a cognitive training manipulation) on speech in noise comprehension in older adults. My results challenge the efficacy of cognitive training more generally, and also provide support for the contribution of sentence context in reducing working memory load. My findings also challenge the ubiquitous use of the Reading Span test as a pure test of working memory. In a second experimental (fMRI) study, I examine the role of attention in audiovisual speech integration, particularly when the acoustic signal is degraded. I demonstrate that attentional processes support audiovisual speech integration in the middle and superior temporal gyri, as well as the fusiform gyrus. My results also suggest that the superior temporal sulcus is sensitive to intelligibility enhancement, regardless of how this benefit is obtained (i.e., whether it is obtained through visual speech information or speech clarity). In addition, I also demonstrate that both the cingulo-opercular network and motor speech areas are recruited in difficult listening conditions. Taken together, these findings augment our understanding of cognitive contributions to the listening process and demonstrate that memory, working memory, and executive control networks may flexibly be recruited in order to meet listening demands in challenging environments.

E-handel- Konkurrent eller komplement för mikroföretag? : En studie om lokala mikroföretag

I dagens samhälle har det skett en strukturomvandling på marknaden gällande detaljhandeln.Strukturomvandlingen har inneburit utveckling av bland annat omnikanaler och e-handelvilket har förändrat företagens affärsmodellsval för att kunna överleva på marknaden. Ehandelnhar i många år setts som en konkurrent för mikroföretag, men det börjar även blimöjligt för mikroföretag att införa ett integrerat system som innebär att den fysiska butikensamverkar med e-handeln. Resultatet av de ökade möjligheterna för mikroföretag är att de kanvälja mellan tre olika affärsmodellsval gällande sin marknadsplats och tillgänglighet avföretaget och sedan utifrån omnikanaler kan företagen välja hur de vill nå ut tillkonsumenterna.I denna studie vill vi få en ökad förståelse för hur lokala mikroföretag arbetar med att behållasin marknadsplats i den ökade konkurrensen som blir i och med e-handelns tillväxt. För attkunna undersöka mikroföretagen har vi tillämpat en kvalitativ metod med djupgåendehalvstrukturerade intervjuer. För att få reda på hur lokala handlare uppfattar marknaden,konkurrensen och handelsutvecklingen, intervjuades fem stycken strategiskt valdadetaljhandelsföretag.Av undersökningen framgick det att en gemensam syn kring marknaden föreligger vilketinnebar att oavsett företagens val så har företagen sitt fokus på konsumenten. Det framgickäven att en av de viktigaste framgångsfaktorerna är att tillgodose konsumenten med högservicegrad och på så sätt skapa en relation. Relationer bidrar till återkommande och lojalakonsumenter vilket i sin tur bidrar till lönsamhet för företaget. Samtliga informanter var enigaom att relationer upprättas i den fysiska butiken och har således valt att fokusera på denenskilda butiken i internets ständiga utveckling. För att attrahera konsumenter till butiken harde valt att tillhandahålla ett unikt sortiment. Sammanfattningsvis har internet och handelnsutveckling och den konkurrens det medför på lokala handlarna blivit tvungna ta ställning tilldet och anpassa en affärsmodell utefter sin egen verksamhet.

Richard Yates: re-writing postwar American culture

This thesis explores the fiction of American author Richard Yates to propose that his work provides an insistent questioning and alternative vision of postwar American culture. Such an approach is informed by a revisionist account of four distinct yet interconnected areas of postwar culture: the role of the non-heroic soldier stepping in and out of World War II; suburbanisation and fashioning of anti-suburban performance; demarcation of gender roles and unraveling of sexual conservatism in the 1950s; consideration of what constituted the normative within postwar discourse and representations of mental illness in Yates’ work. These four spheres of interest form the backbone to this study in its combined aim of reclaiming Yates’ fiction in line with a more progressive historical framework while shaping a new critical appreciation of his fiction. Such analysis will be primed by an opening discussion that illustrates how Yates’ fiction has frequently been ensconced in a limited interpretative lens: an approach, that I argue, has kept Yates on the periphery of the canon and ultimately resulted in the neglect of an author who provided a rich, progressive and historically significant dialogue of postwar American life. This PhD arrives at a point when Yatesian scholarship is finally gaining momentum after the cumulative impact of a comprehensive biography, a faithful film adaptation of his seminal text Revolutionary Road (1961), plus the recent re-issue of his catalogue of work. An assessment as to why he remained on the margins of success for the duration of his career is therefore of pressing interest in light of this recent critical and commercial recognition.