3,303 research outputs found

    Estimativa da Evaporação em Albufeiras do Sul de Portugal pelo Modelo FLAKE

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    The aim of this work is to be able to simulate the evaporation from reservoirs in southern Portugal(a drought prone area) by applying the FLAKE lake model. The model was forced with over-lake atmospheric measurements from the Water Institute monitoring network over the period from 2002 to 2006. Simulation results were compared against observational water temperature profiles and a statistic analysis was used to set optimal model parameters for each reservoir studied. Comparison shows that the model is able to simulate the annual cycle of water temperatures, and to predict realistic patterns of evaporation rates

    Competitiveness and Public-Private Partnerships: Towards a More Decentralised Policy

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    Public-private partnerships are a recent instrument for social and economic development policies. A more decentralised policy is supposed to increase focus and effectiveness and to involve agencies that are closer to firms and that have a more narrow range of objectives. In this contribution, we analyse the pattern of the so-called PIP (Partnerships and Public Initiatives) projects, approved between 2000 and the 30th June of 2003 in the framework of the Portuguese Operational Program for the Economy. By using HOMALS and K-means cluster analysis, we were able to characterise the decentralisation pattern and to identify typical clusters for the PIP projects. The results show clearly that a greater decentralisation is linked to partnerships while public initiatives are closer to the conventional pattern of public intervention. The results also show that partnerships are mainly focused in specific sectors and / or in specific regions, being conducted by private agencies that have chiefly a sectoral or regional nature. However, we have observed a trade-off between policy decentralization and structural change goals because decentralization has originated a bias towards the present more representative sectors. Also, decentralization has generated an extremely unequal access of local economies to the PIP instrument, favoring the more developed areas of the country.Public-private partnerships; Competitiveness policy; Decentralization

    Public-Private Partnerships and the Promotion of Collective Entrepreneurship

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    Public-private partnerships (PPP) are a recent instrument for social and economic development policies. Within the framework of competitiveness policy, PPP are an adequate instrument to promote collective entrepreneurship. Through this instrument, some market failures can be overcome and a better provision of strategic services can be afforded to firms. Also, PPP can be able to promote co-ordination between public and private partners and lead to specific innovative networks. PPP correspond to a more decentralised policy and they are supposed to increase focus and effectiveness and to involve agencies that are closer to firms and that have a more narrow range of objectives. In this contribution, we analyse the pattern of the so-called partnerships projects, approved between 2000 and the 30th june of 2003 in the framework of the Portuguese Operational Program for the Economy. By using HOMALS and K-means cluster analysis, we were able to characterise PPP and to identify typical clusters for the PPP projects. On one hand, the results show that policy decentralization brought by partnerships has promoted or reinforced a more specialized institutional framework (mainly national, sectoral or regional entrepreneurial associations). But, on the other hand, PPP had a small impact in the promotion of specific networks and/or in innovation. Collective entrepreneurship induced by PPP instrument has presented a clear bias toward the provision of services that have a public or semi-public nature, by the fact that firms that can use these services are in a large number (all the firms of a sub sector or even larger universes). But technological projects and/or projects addressed to specific networks of firms were very few. In particular, the impact of PPP on structural change seems to have been short.Public-private partnerships; Competitiveness policy; Entrepreneurship; Collective entrepreneurship

    Competitiveness and Public-Private Partnerships: Towards a More Decentralised Policy

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    In this contribution, we analyse the pattern of the so-called PIP (Partnerships and Public Initiatives) that have been approved between 2000 and mid-2003 in the POE1 framework. In particular, we will evaluate the extent of decentralisation that this new instrument has generated in competitiveness policy. Partnership approaches are a relatively recent phenomenon, but partnerships have received widespread attention and support from economic and political agents, including policy makers at national, regional and local levels. In fact, the term “public-private partnership” covers a wide range of concepts and practices. In our contribution, we will focus on partnerships in a competitiveness policy framework. In a first section, we discuss briefly the meaning and the extent of what we call competitiveness policy. Then, in a second section, we focus our attention in public-private partnerships as a specific instrument for policy. In particular, we make a first assessment on the distinctive principles that differentiate public-private partnerships from more traditional instruments such as direct investment in public agencies or direct subventions to firms. We follow the perspective that these principles, mainly decentralization of policy, may contribute to a greater effectiveness of policy, because a more decentralised policy is supposed to increase focus and accountability and to involve agencies with specialized skills and a more narrow range of objectives. But, also, we will refer that some inefficiencies and some lack of equity may arise from the use of private-public partnerships instrument. Finally, in the main section of this contribution, we will analyse the above-mentioned questions considering the case of the 131 PIP projects approved and financed by the POE between 2000 and mid-2003. As the major part of the variables used are nominal, and in order to define the decentralization pattern induced by this new instrument, we will use multivariate data analysis techniques in order to establish associations between several variables linked to decentralisation criteria and, also, to identify clusters of projects.

    Mobile learning: benefits of augmented reality in geometry teaching

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    As a consequence of the technological advances and the widespread use of mobile devices to access information and communication in the last decades, mobile learning has become a spontaneous learning model, providing a more flexible and collaborative technology-based learning. Thus, mobile technologies can create new opportunities for enhancing the pupils’ learning experiences. This paper presents the development of a game to assist teaching and learning, aiming to help students acquire knowledge in the field of geometry. The game was intended to develop the following competences in primary school learners (8-10 years): a better visualization of geometric objects on a plane and in space; understanding of the properties of geometric solids; and familiarization with the vocabulary of geometry. Findings show that by using the game, students have improved around 35% the hits of correct responses to the classification and differentiation between edge, vertex and face in 3D solids.This research was supported by the Arts and Humanities Research Council Design Star CDT (AH/L503770/1), the Portuguese Foundation for Science and Technology (FCT) projects LARSyS (UID/EEA/50009/2013) and CIAC-Research Centre for Arts and Communication.info:eu-repo/semantics/publishedVersio

    The fractional volatility model : no-arbitrage, leverage and completeness

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    When the volatility process is driven by fractional noise one obtains a model which is consistent with the empirical market data. Depending on whether the stochasticity generators of log-price and volatility are independent or are the same, two versions of the model are obtained with different leverage behaviors. Here, the no-arbitrage and completeness properties of the models are rigorously studied

    Dpws middleware to support agent-based manufacturing control and simulation

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    Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para obtenção do grau de Mestre em Engenharia Electrotécnica e de ComputadoresIn present manufacturing systems, the current challenge is the development of highly reconfigurable, truly distributed solutions. The tendency is to build manufacturing systems with autonomous, intelligent and distributed components that will support reconfiguration and adaptability. The most promising paradigms for the implementation of such systems are multi-agents and service oriented architectures (SOA), mainly over the DPWS (Device Profile for Web Services) implementation which was aimed at devices. An important limitation of most current multi-agent systems is that the management system is not totally distributed. Failure in the agent responsible for the registry can overthrow the entire system. DPWS does not have this limitation, since the management system is totally distributed. However, DPWS does not support agent autonomy notions as efficiently. The possibility of creating a truly distributed multi-agent system by linking both approaches led to this thesis. A Middleware layer was developed that enables agents to benefit from DPWS functionalities in order to reach the proposed goal. This middleware layer joins agents, databases, hardware, simulators, human interface applications such as production system management, error correction and maintenance, etc. To prove this concept a 3D model of an agent controlled manufacturing system with transporters augmented with DPWS communication interfaces was developed
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