8,593 research outputs found
On the cohomology of Brill-Noether loci over Quot schemes
Let C be a smooth projective curve over the field of the complex numbers. We
consider Brill-Noether loci over the moduli of maps from C to the Grassmannian
G(m,n) and the corresponding Quot schemes of quotients of a trivial vector
bundle on C compactifying the spaces of morphisms. We study in detail the case
in which m=2, n=4. We prove results on the irreducibility and dimension of
these Brill-Noether loci and we address explicit formulas for their cohomology
classes. We study the existence problem of these spaces which is closely
related with the problem of classification of vector bundles over curves
Managing strategic change at the regional level: Regional networks of economic development and industry clusters
Regional Development Networks of private and public organisations is a contemporary phenomenon that is reshaping strategies of local development by introducing new agents and more dynamism and flexibility in the decision making process. This approach reflects new trends in corporate and business development, balancing the tensions produced by competition and collaboration. Regions as networks incubators are regions with specific characteristics enhancing an emergent and evolving movement of networking between organisations working for the regional development. The purpose of this paper is to present the network scenario of two regions from Spain and Australia that exemplify the emergence and evolution of networks' incubator and the relevance to their regional development. Both regions are facing economic restructuring as a result of regional spatial competition on the global market. These regions could be characterised as learning regions and a definition of the network incubator will be provided. The paper will argue that regional networks are a development tool, which could act as a catalyst in stimulating economic revitalisation. It is possible to engineer this tool, stimulating the conditions of the region as a network incubator. Key Words: regions of networks' incubators, learning regions, local development
Predictability of Extreme Intensity Pulses in Optically Injected Semiconductor Lasers
The predictability of extreme intensity pulses emitted by an optically
injected semiconductor laser is studied numerically, by using a well-known rate
equation model. We show that symbolic ordinal time-series analysis allows to
identify the patterns of intensity oscillations that are likely to occur before
an extreme pulse. The method also gives information about patterns which are
unlikely to occur before an extreme pulse. The specific patterns identified
capture the topology of the underlying chaotic attractor and depend on the
model parameters. The methodology proposed here can be useful for analyzing
data recorded from other complex systems that generate extreme fluctuations in
their output signals
Nanotechnology, Industry Competitiveness and University Strategies: the Case of the UWS Nanotechnology Network in South-West Sydney
University-industry alliances have long been pursued by public funded programs hoping to boost innovation spillovers in a geographical or cognitive area of research-strength by universities. However, there is still a lack of industry-university cooperation in many fields while at the same time the benefits of universities to their regionsâ knowledge intensity is firmly advocated (Acs 2004, Martinez-Fernandez & Leevers 2004, Martinez-Fernandez 2004)). The issue is not limited to the dissemination of knowledge, a traditional role of universities, but to introducing change into the regionâs innovation system through activities that increase industry competitive advantage. Results from a project conducted in South-West Sydney from 2003 to 2005 shows that active industry engagement by Universities offering specific expertise in frontier technologies has a positive effect in university-industry cooperation if compared with other technologies well established in the private sector. The project results also show that the role of Universities as active facilitators of industry engagement in frontier technologies is a critical element in the regional/local innovation system where the university operates. The paper discusses first the context of the emergence of the UWS Nanotechnology Network as a sophisticated knowledge intensive service activity led by the University. Secondly the paper discusses the particular case of nanotechnology as a science in an early path and the role of universities at this particular stage. Thirdly, the paper discusses the use and barriers of firms to nanotechnology applications and the role played by UWS during the duration of the project. Finally policy issues arise in relation to the role of the public education sector in the early promotion of frontier technologies. References Acs, Z. (2002) Innovation and the Growth of Cities. Edward Elgar Publishing Ltd. Martinez-Fernandez, M.C. (2004) âRegional Collaboration Infrastructure: Effects in the Hunter Valley of NSWâ, Australian Planner Vol 41(4); Planning Institute of Australia: Queensland. Martinez-Fernandez, M.C. and K. Leevers (2004) âKnowledge Creation, Sharing and Transfer as an Innovation Strategy: The Discovery of Nano-technology by South-West Sydneyâ. International Journal of Technology Management (IJTM), Volume 28 (3/4/5/6): 560-581.
The best of two worlds:Assessing the use of administrative data for the study of unemployment using the labour force survey as a benchmark
Integration of UAS in the civil airworthiness regulatory system: present and future
The last years are witnessing a number of initiatives worldwide devoted to assess the safety levels of the unmanned aircraft. These initiatives are very heterogeneous; some of them are centred in airworthiness aspects while others focus on operations. From the point of view of a potential UAS manufacturer the actual situation is plenty of uncertainties in relation to the regulations to be applied for certifying the design, manufacturing and maintenance, and from the point of view of the potential operator the situation is analogous with respect to operational procedures. In the present work the emphasis is on the manufacturerâs situation. The objective of this work is to clarify the present civil airworthiness regulatory scene by summarizing all the regulatory efforts up to date and preparing a comparative analysis of them. In this comparison, the manned regulations are included too. The most representative state-of-the-art UAS are analyzed from the point of view of the existing and the future regulatory framework. The main aspects to be considered are related to the airworthiness certification (performances, structural design, etc) for which a quantitative comparison is established in order to clarify how the new regulatory framework, mainly based on the conventional aircraft certification codes, will affect future UAS, compared to the existing regulation
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