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Whenever a DS-CDMA signal (direct sequence code division multiple access) is the sum of several components associated to different spreading codes (e.g., the DS-CDMA signal to be transmitted by the BS (Base Station) in the downlink, or any multicode DS- CDMA signal), it has high envelope fluctuations, and a high PMEPR (Peak-to-Mean Envelope Power Ratio) setting strong linearity requirements for the power amplifiers. For this reason, it is desirable to reduce the envelope fluctuations of the transmitted signals. A promising class of nonlinear signal processing schemes, combining a nonlinear operation in the time- domain with a linear, frequency-domain filtering operation, was recently proposed for reducing the envelope fluctuations (and, inherently, the PMEPR) of DS-CDMA signals, while maintaining the spectral occupation of the correspo...
A gene encoding a potential NADPH-dependent cinnamyl alcohol dehydrogenase (QsCAD1) (GenBank accession no: AY362455) was identified in Quercus suber (cork oak). Its complete cDNA sequence was obtained by RACE-PCR, starting from total RNA extracted from roots of seedlings of Q. suber, infected with Phytophthora cinnamomi, the causal agent of the decline and sudden death of Q. suber and Quercus ilex subsp. rotundifolia in the Iberian Peninsula. Sequence information to perform the RACE-PCR
was acquired from a polymorphic fragment (C9), specifically identified by cDNA-AFLP, in leaves of epicormic shoots of a cork oak
tree that suffered sudden death. RT-PCR and hybridization analysis showed that the QsCAD1 gene is up-regulated in root seedlings
of Q. suber infected with P. cinnamomi. QsCAD1 has a high structural homology with VR-ERE (Vig...
Este artigo tem como objectivo mostrar formas de usar a linguagem PHP para a criação de páginas dinâmicas web,através dos conteúdos fornecidos por uma base de dados. Além de uma introdução ao PHP e ao conceito de ODBC, mostrar-se-ão os princípios fundamentais de uma aplicação deste género e referências a softWare útil para a programação em PHP.
Dissertação mest., Marketing, Universidade do Algarve, 2007
Dissertação mest., Psicologia, Universidade do Algarve, 2009
A incerteza, a complexidade, a imprevisibilidade, o paradoxo, a turbulência e o caos são termos que entraram, nestes últimos anos, no vocabulário dos gestores e dos teóricos da gestão. Face à rápida mudança da envolvente, implícita nestas expressões, a estratégia e a organização das empresas sofre transformações mais ou menos profundas e mais ou menos frequentes. Esta instabilidade combinada com as soluções descobertas por algumas empresas e as apontadas por certos gurus da gestão, colocam a dúvida sobre a utilidade da estratégia. Estratégia que é considerada por muitos como uma orientação geral predeterminada e duradoura.
Inúmeros métodos e modelos foram desenvolvidos durante a segunda metade do século para apoio à formulação/implementação da estratégia empresarial. Uns reformulados, uns novos e outros menos revolucionários do que ap...
Chondrocyte gene regulation is important for the generation and maintenance of cartilage tissues. Analysis of the transcriptional regulation of cartilage-specific genes, encoding both collagenous and noncollagenous proteins, provides a useful strategy to identify transcription factors (TFs) that control chondrocyte specification and differentiation. Our work aims at the identification of candidate TFs important for cartilage maintenance and development through an in silico approach. In order to better define the transcriptional regulatory networks that affect chondrogenesis in zebrafish we propose a combination of comparative promoter analysis and transcription factor binding site analysis using a TRANSFAC position weight matrix search to identify cis-regulatory transcription factor binding motifs in a set of cartilage characteristic g...
Dissertação de mest., Psicologia da Educação, Faculdade de Ciências Humanas e Sociais, Universidade do Algarve, 2009
Abstract The Portuguese power grid company wants to improve the accuracy of the electricity
load demand forecast within an horizon of 48 hours, in order to identify the need of reserves to be
allocated in the Iberian Market. In this work we present updated results on the identi cation of
radial basis function neural network load demand predictive models. The methodology follows
the principles already employed by the authors in di erent applications: the NN models are
trained by the Levenberg-Marquardt algorithm using a modi ed training criterion, and the
model structure (number of neurons and input terms) is evolved using a multi-objective genetic
algorithm. The set of goals and objectives used in the model optimisation re
ect di erent
requirements in the design: obtaining good generalisation ability, good balance between one-...
