Solid immersion lens at the aplanatic condition for enhancing the spectral bandwidth of a waveguide grating coupler

We report a technique to substantially boost the spectral bandwidth of a conventional waveguide grating coupler by using a solid immersion cylindrical lens at the aplanatic condition to create a highly anamorphic beam and reach a much larger numerical aperture, thus enhancing the spectral bandwidth of a free-space propagating optical beam coupled into a single-mode planar integrated optical waveguide (IOW). Our experimental results show that the broadband IOW spectrometer thus created almost doubles (94% enhancement) the coupled spectral bandwidth of a conventional configuration. To exemplify the benefits made possible by the developed approach, we applied the technique to the broadband spectroscopic characterization of a protein submonolayer; our experimental data confirm the enhanced spectral bandwidth (around 380–nm) and illustrate the potentials of the developed technology. Besides the enhanced bandwidth, the broadband coupler of the single-mode IOW spectrometer described here is more robust and user-friendly than those previously reported in the literature and is expected to have an important impact on spectroscopic studies of surface-adsorbed molecular layers and surface phenomena

Canonical correlation analysis and DEA for azorean agriculture efficiency

In this paper we will document the application of canonical correlation analysis to variable aggregation using the correlations of the original variables with the canonical variates. A case study, about farms in Terceira Island, with a small data set is presented. In this data set of 30 farms we intend to use 17 input variables and 2 output variables to measure DEA efficiency. Without any data reduction procedure several problems known as “curse of dimensionality” are expected. With the data reduction procedures suggested it was possible to conclude quite acceptable and domain consistent conclusions.N/

Azorean agriculture efficiency by PAR

The producers always aspire at increasing the efficiency of their production process. However, they do not always succeed in optimizing their production. In the last years, the interest on Data Envelopment Analysis (DEA) as a powerful tool for measuring efficiency has increased. This is due to the large amount of data sets collected to better understand the phenomena under study, and, at the same time, to the need of timely and inexpensive information. The “Productivity Analysis with R” (PAR) framework establishes a user-friendly data envelopment analysis environment with special emphasis on variable selection and aggregation, and summarization and interpretation of the results. The starting point is the following R packages: DEA (Diaz-Martinez and Fernandez-Menendez, 2008) and FEAR (Wilson, 2007). The DEA package performs some models of Data Envelopment Analysis presented in (Cooper et al., 2007). FEAR is a software package for computing nonparametric efficiency estimates and testing hypotheses in frontier models. FEAR implements the bootstrap methods described in (Simar and Wilson, 2000). PAR is a software framework using a portfolio of models for efficiency estimation and providing also results explanation functionality. PAR framework has been developed to distinguish between efficient and inefficient observations and to explicitly advise the producers about possibilities for production optimization. PER framework offers several R functions for a reasonable interpretation of the data analysis results and text presentation of the obtained information. The output of an efficiency study with PAR software is self- explanatory. We are applying PAR framework to estimate the efficiency of the agricultural system in Azores (Mendes et al., 2009). All Azorean farms will be clustered into homogeneous groups according to their efficiency measurements to define clusters of “good” practices and cluster of “less good” practices. This makes PAR appropriate to support public policies in agriculture sector in Azores.N/

Comparative advantage of organic wheat production in the Western Cape

In a context in which the framework of agricultural policy and business is changing radically the objective of the government and farmers should be to support the development of systems that look likely to be winners in the future. As a result this paper uses a Policy Analysis Matrix (PAM) to determine whether wheat production would have a comparative advantage if produced under organic practices. The paper starts by analysing the comparative advantage of wheat under conventional practices, and later contrasts conventional with organic practices. The results of the analyses mainly indicate a comparative advantage for wheat grown under organic practices especially when the social cost benefit ratio (SCB) is incorporated into the analyses. This is because the domestic resource cost (DRC) criterion that is used by the PAM is confirmed to understate the social profitability of systems that use domestic factors intensively like organic wheat systems and favours systems that use less of these factors like conventional systems. The results also show the existence of distortions in the market even if wheat were to be produced under organic practises, although these are shown to be less than for wheat produced under conventional practices.Crop Production/Industries,

From synchronization to multistability in two coupled quadratic maps

The phenomenology of a system of two coupled quadratic maps is studied both analytically and numerically. Conditions for synchronization are given and the bifurcations of periodic orbits from this regime are identified. In addition, we show that an arbitrarily large number of distinct stable periodic orbits may be obtained when the maps parameter is at the Feigenbaum period-doubling accumulation point. An estimate is given for the coupling strength needed to obtain any given number of stable orbits.Comment: 13 pages Latex, 9 figure

Ciências de informação geográfica no apoio à decisão.

"A utilização de informação geográfica na tomada de decisão é já bastante usual. As decisões relacionadas com o posicionamento ou localização de estruturas e pessoas no espaço beneficiam com a observação da relação espacial entre os objectos. Os investimentos efectuados nos últimos anos com a aquisição de Sistemas de Informação Geográfica (SIG) e integração de bases de dados de acesso partilhado, visam a optimização e coerência das decisões e a avaliação de riscos. [...]"

Processo de Bolonha (Parte I): um novo paradigma para o ensino superior?

"É opinião generalizada que o Processo de Bolonha, introduzido pela Declaração de Bolonha, assinada por 29 países europeus em 19 de Junho de 1999, deverá conduzir a profundas mudanças no nosso sistema de ensino superior público. Para se entenderem algumas das suas implicações é necessário, primeiro, resumir a sua, ainda, curta história, perceber os seus objectivos gerais e específicos e, ainda, o desenvolvimento para a aplicação ao caso Português. […].

Transforming trauma with games for social change

This research explores and develops intersections between social change and games by examining ways in which social change may be propelled through creating and playing a game by persons that have experienced trauma. The framework touches upon game theory, digital and art games, and learning through play, which may bring self-directed learning. This game creation and play may assist development or acquisition of literacy skills like critical and reflective thinking, which may in turn bring signs of social change. Pilot study data analyses, which covered areas such as verbal or physical violence/abuse and gender equality, show tendencies toward social change that merit investigation for future research. This qualitative research utilizes case studies in communities from Portuguese Universities.info:eu-repo/semantics/publishedVersio

Apoiar decisões complexas.

Texto publicado originalmente no jornal Açoriano Oriental, secção "Bits & Bytes", de 7 de Abril de 2007."[…]. A discussão sobre a localização do novo aeroporto de Lisboa chama a atenção para uma área do apoio à decisão com distintos investigadores nacionais: a análise de decisão multicritério. Nesta metodologia, começa-se por definir um grupo de alternativas admissíveis (i.e., passíveis de serem colocadas em prática) e mutuamente exclusivas, de modo a apenas ser possível escolher uma e só uma delas, conhecidas por alternativas de decisão. Assim, decidir é escolher a melhor de entre o conjunto de alternativas de decisão pré-definido. A definição do conjunto de alternativas de decisão pode ser um processo complexo e demorado. […]"