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Contém referências bibliográficas
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Vol.I : Plant names. - 1979. - 580 p
Bibliografia : p. 308
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Trabalho elaborado como dissertaçäo para efeito de obtençäo do grau de Doutor em Engenharia Agrícola
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Ciência veterinária e higiene
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Tit. Orig.: On entrepreneurship
Estudo electrofisiológico
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Relatório do projeto final de licenciatura em Design de Interiores e Equipamento
Relatório do projeto final de licenciatura em Design de Moda e Têxtil
Dissertaçäo de Doutoramento em Literatura Inglesa
Tecnologia da educação
Do you feel what I feel? Emotional development in children with ID is a study that has emerged as a need to deepen the knowledge on this area. It has focused in a case study methodology with the use of three validated instruments to a sample of thirty-four children, twenty attending the 1st cycle and fourteen attending the 2nd, in two school groupings of Castelo Branco city. Seventeen of them have mild intellectual disability and seventeen are “normal”, aged between 8 and 14.
The research has been developed in order to give answers to questions related with the way that children with intellectual disability (ID) express, identify and regulate their emotions.
The results suggest that children with intellectual disability identify emotions, in a general way, the same way that “normal” children do, nevertheless, there are some difficulties in the understanding and organization of coping strategies.
In this work, the effect of single overloads on plasticity induced crack closure is studied. An elastic-plastic
finite element model was developed and the crack opening level was calculated from the contact forces
along the crack flank. The effects of the loading parameters and stress state are analysed, and the mechanisms
behind crack closure variations are identified. An overload is a traumatic event that eliminates
material’s memory relative to the load history. Crack tip blunting is the mechanism behind this memory
loss, since it eliminates crack closure. Material hardening has a major relevance on the evolution of plastic
blunting, which was evident in the variation of the CTOD parameter. On the other hand, the overload
produces strong plastic deformation ahead of the crack tip, giving rise to conditions for the rapid generation
of crack closure higher than before the event. The peak of crack closure was found to increase linearly
with the load increase above the maximum baseline value. The crack is totally closed for overload
ratios of about 2.5. Empirical models were developed for the peak of crack closure, for the delay of this
peak and for the stabilization distance after the overload. Finally, the stress state was found to have a
major effect on crack closure level after an overload.
With the massive deployment of broadband access to the end-users, the continuous improvement of the hardware capabilities of end devices and better video compression techniques, acceptable conditions have been met to unleash over-the-top bandwidth demanding and time-stringent P2P applications, such as multiview real-time media distribution. Such applications enable the transmission of multiple views of the same scene, providing consumers with a more immersive visual experience. This article proposes an architecture to distribute multiview real-time media content using a hybrid DVB-T2, client-server and P2P paradigms, supported by an also novel QoS solution. The approach minimizes packet delay, interar- rival jitter, inter-ISP traffic and traffic at the ISP core network, which are some of the main drawbacks of P2P networks, whilst still meeting stringent QoS demands. The proposed architecture uses DVB-T2 to distribute a self-contained and fully decodable base-layer video signal, assumed to be always available to the end-user, and an IP network to distribute in parallel - with increased delay - additional IP video streams. The result is a decoded video quality that adapts to individual end-user conditions and maxi- mizes viewing experience. To achieve its target goal this architecture: defines new services for the ISP’s services network and new roles for the ISP core, edge and border routers; makes use of pure IP mul- ticast transmission at the ISP’s core network, greatly minimizing bandwidth consumption; constructs a geographically contained P2P network that uses P2P application-level multicast trees to assist the dis- tribution of the IP video streams at the ISP access networks, greatly reducing inter-ISP traffic, and; de- scribes a novel QoS control architecture that takes advantage of the Internet resource over-provisioning techniques to meet stringent QoS demands in a scalable manner. The proposed architecture has been im- plemented in both real test bed implementation and ns-2 simulations. Results have shown a highly scal- able P2P overlay construction algorithm, with very fast computation of application-level multicast trees (in the order of milliseconds), and efficient reaction to peer-churn with no perceptually annoying impair- ments noticed. Furthermore, enormous bandwidth savings are achieved at the ISP core network, which considerable lower management and investment costs in infrastructure. The QoS based results have also shown that the proposed approach effectively deploys a fast and scalable resource and admission control mechanism, considerably lowering signalling events using a per-class over-provisioning approach thus preventing per-flow QoS reservation signalling messages. Moreover, it is aware of network link resources in real-time and supports for service differentiation and network convergence by guaranteeing that each admitted traffic flow receives the contracted QoS. Finally, the proposed architecture for Multiview Real- Time Media Distribution for Next Generation Networks, as a component for a large project demonstrator, has been evaluated by an independent panel of experts following ITU recommendations, obtaining an excellent evaluation as computed by Mean Opinion Score.
In this article, a three-dimensional finite element model (FEM) is used to predict the crack growth at the weld toe of a pre-fatigued T-joint that was repaired with a remelting technique. The numerical models were developed using the MSC.Marc software. Fatigue life is estimated by integrating the Paris-Erdogan law. The stress intensity factors are obtained by the virtual crack closure technique (VCCT). The T-welded joints, made of S355 steel, are obtained by covered electrode process and pre-cracked by fatigue. These welded joints were repaired by TIG dressing. The stress field generated by this dressing technique was estimated using a FEM model, presented in authors’ previous works. For the crack growth was used the VCCT three-dimensional model recently presented by the authors to predict the effect of overloads. The pre-existence of an elliptical crack at the weld toe, with a depth of 0.5 mm was considered. It is also studied the growth of pre-existing cracks which have been poorly repaired. It was observed that the TIG dressing produce residual compression stress fields on the weld toe that causes a delay in crack growth. The obtained results are compared with experimental ones. The fatigue’s lives obtained by simulations with the numerical model presented in this paper allows to evaluate the application conditions of TIG remelting technique in the repair of pre-cracked welded joints.
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Part. 5 : L'Europe transparent, l'Europe en direct. - [4] p.
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Manuseamento, transporte, armazenamento e protecçäo de produtos de origem vegetal
Bibliografia : p. 363
Ciência e tecnologia alimentar
Contaminaçäo e toxicologia alimentar
Composiçäo dos alimentos
Bibliografia, p. 380
Inclui índice de sintomas e possíveis causas patológicas e glossário
Enfermagem obstétrica
Inclui índice de sintomas e possíveis causas patológicas e glossário
The use of a centralised planning scheduler in fieldbus-based systems requiring real-time operation has proved to be a good compromise between operational ̄exibility and timeliness guarantees. It is particularly well adapted to embedded systems based on low-processing power microcontrollers due to the low overhead it imposes.
In this paper a preliminary implementation of a hardware scheduling coprocessor based on the planning paradigm is presented. The coprocessor is installed in a special node of the fieldbus, the bus arbiter, and generates scheduling tables to be dispatched by the node CPU. With this solution it is possible to decrease the response time to changes in the system con®guration or message parameters of the software- based planning scheduler. This opens the possibility of allowing automatic on-line changes requested by system nodes in addition to the ones requested by human operators, thus improving system reactivity.
The paper includes a short review of the planning technique and a discussion on the motivation to develop the coprocessor as well as on recent similar and related work. The coprocessor architecture and several implementation details such as its interface with the arbiter CPU are presented. The initial calculations showing the feasibility of the unit are also derived, together with the first real implementation of the coprocessor itself.
Soil degradation by water is a serious environmental problem worldwide, with specific climatic factors being the major causes. We investigated the relationships between synoptic atmospheric patterns (i.e. weather types, WTs) and runoff, erosion and sediment yield throughout the Mediterranean basin by analyzing a large database of natural rainfall events at 68 research sites in 9 countries. Principal Component Analysis (PCA) was used to identify spatial relationships of the different WTs including three hydro-sedimentary variables: rainfall, runoff, and sediment yield (SY, used to refer to both soil erosion measured at plot scale and sediment yield registered at catchment scale). The results indicated 4 spatial classes of rainfall and runoff: (a) northern sites dependent on North (N) and North West (NW) flows; (b) eastern sites dependent on E and NE flows; (c) southern sites dependent on S and SE flows; and, finally, (d) western sites dependent on W and SW flows. Conversely, three spatial classes are identified for SY characterized by: (a) N and NE flows in northern sites (b) E flows in eastern sites, and (c) Wand SW flows in western sites. Most of the rainfall, runoff and SY occurred during a small number of daily events, and just a few WTs accounted for large percentages of the total. Our results confirm that characterization by WT improves understanding of the general conditions under which runoff and SY occur, and provides useful information for understanding the spatial variability of runoff, and SY throughout the Mediterranean basin. The approach used here could be useful to aid of the design of regional water management and soil conservation measures.
A comprehensive overview of the sustainability of wood-based technologies for the production of high-quality and differentiated wine spirits, and the research carried out in this field is provided in this chapter. Barrels are actively involved in the wine spirit's composition and sensory changes due to the transfer of oxygen, and extractive compounds from wood to the beverage. The key physicochemical phenomena and determining factors at the aging stage are illustrated with regard to the sustainable use of wood both in barrels and through innovative technologies for wine spirit's aging. A broad perspective is offered to readers on the fair and sustainable use and reuse of wood, the circular economy and its relationship with cooperage efficiency, including responsible relations/commitments in the entire value chain (from the forest to the aged wine spirit).
