Uma solução da equação difusão-advecção com o termo contragradiente

Neste trabalho, apresenta­se uma solução para equação de difusão­advecção considerando o  termo  contragradiente  que  é um termo  adicional. Esse termo  adicional  contém informações  sobre a assimetria, escala de tempo Lagrangeana e velocidade turbulenta vertical. A solução  da equação foi obtida pela utilização da técnica de Transformada de Laplace, considerando a  Camada  Limite  Planetária  (CLP)  como  um  sistema  de  multicamadas.  Os  parâmetros  turbulentos foram derivados da teoria de difusão estatística de Taylor, combinada com a teoria  da similaridade. Assim, são apresentadas simulações para diferentes valores de assimetria, o  que  propiciou  a  obtenção  de  uma  concentração  de  contaminantes  em  diferentes  alturas,  em  uma  camada  limite  convectiva.  A  avaliação  do  desempenho  do  modelo,  considerando  a  assimetria  no  processo  de  dispersão  de  poluentes  atmosféricos, foi realizada  através  de  um  experimento  de  tanque  convectivo  tradicional.  Nesse  experimento,  o  termo  contragradiente  influenciou a concentração de poluentes para uma camada limite convectiva. Entretanto, com  as  parametrizações  utilizadas,  o  modelo  não  conseguiu  captar  de  forma  eficiente  o  comportamento da concentração em pontos mais distantes da fonte.

Caracterização da matéria orgânica nas zonas ripárias em diferentes condições de preservação no Cerrado do Planalto Central do Brasil

Tese (doutorado)—Universidade de Brasília, Instituto de Ciências Biológicas, Programa de Pós-Graduação em Ecologia, 2016.

A União Europeia como potência global? As alterações do Tratado de Lisboa na política externa e de defesa

Este artigo aborda as alterações que o Tratado de Lisboa introduziu na política externa e de defesa, tendo em conta a gradual alteração do conceito estratégico da União Europeia que pretende transformá-la numa potência global. Começa por enquadrar a intervenção da União Europeia na política internacional, com a adoção de uma política externa e de segurança pelo Tratado de Maastricht. Em seguida, refere as inovações do Tratado de Lisboa nessa política, analisando os aspectos de maior relevo.

Application to quantify fetal lung branching on rat explants

Recently, regulating mechanisms of branching morphogenesis of fetal lung rat explants have been an essential tool for molecular research. The development of accurate and reliable segmentation techniques may be essential to improve research outcomes. This work presents an image processing method to measure the perimeter and area of lung branches on fetal rat explants. The algorithm starts by reducing the noise corrupting the image with a pre-processing stage. The outcome is input to a watershed operation that automatically segments the image into primitive regions. Then, an image pixel is selected within the lung explant epithelial, allowing a region growing between neighbouring watershed regions. This growing process is controlled by a statistical distribution of each region. When compared with manual segmentation, the results show the same tendency for lung development. High similarities were harder to obtain in the last two days of culture, due to the increased number of peripheral airway buds and complexity of lung architecture. However, using semiautomatic measurements, the standard deviation was lower and the results between independent researchers were more coherent

Application to quantify fetal lung branching on rat explant

Recently, regulating mechanisms of branching morphogenesis of fetal lung rat explants have been an essential tool for molecular research. The development of accurate and reliable segmentation techniques may be essential to improve research outcomes. This work presents an image processing method to measure the perimeter and area of lung branches on fetal rat explants. The algorithm starts by reducing the noise corrupting the image with a pre-processing stage. The outcome is input to a watershed operation that automatically segments the image into primitive regions. Then, an image pixel is selected within the lung explant epithelial, allowing a region growing between neighbouring watershed regions. This growing process is controlled by a statistical distribution of each region. When compared with manual segmentation, the results show the same tendency for lung development. High similarities were harder to obtain in the last two days of culture, due to the increased number of peripheral airway buds and complexity of lung architecture. However, using semiautomatic measurements, the standard deviation was lower and the results between independent researchers were more coherent.

The impact of size and age of the company on assessing financial risk

Textiles and tourism sectors are two important sectors in Portuguese economy. Its high exposure to both internal and international economy volatility transform the companies operating in these economic sectors especially vulnerable to recent economic crises in Portugal and European Union. The objective of this paper is to evaluate and understand the impact of size and age on the financial health of textile and tourism companies, measured by economic indices. An empirical based model is proposed. Its implications are derived and tested on a sample of 4061 Portuguese companies from textile and tourism sector, during the period 2005-2009. The results conclude that age has a stronger impact on the risk of failure than size. Whereas the effect of age is generally positive regarding the financial health of the company, the effect of size is less clear and depends on the age of the company.

The impact of size and age of the company on assessing financial risk.

Textiles and tourism sectors are two important sectors in Portuguese economy. Its high exposure to both internal and international economy volatility transform the companies operating in these economic sectors especially vulnerable to recent economic crises in Portugal and European Union. The objective of this paper is to evaluate and understand the impact of size and age on the financial health of textile and tourism companies, measured by economic indices. An empirical based model is proposed. Its implications are derived and tested on a sample of 4061 Portuguese companies from textile and tourism sector, during the period 2005-2009. The results conclude that age has a stronger impact on the risk of failure than size. Whereas the effect of age is generally positive regarding the financial health of the company, the effect of size is less clear and depends on the age of the company.

Edward Said Um Intelectual Crítico e Cosmopolita

Edward Said, palestiniano cidadão do mundo, historiador crítico da literatura e da cultura preocupa-se em analisar e desmistificar as representações ideológicas que afirmam a superioridade de uma cultura sobre as outras. Em Orientalismo , publicado originalmente em 1978, demonstra como o colonialismo europeu constrói uma representação do mundo oriental, especialmente do mundo árabe e muçulmano, em que os representados surgem como seres incapazes de autonomia, racionalidade e autogoverno. Como contraponto a esta concepção, desenvolve-se, no período da emancipação e das independências coloniais, uma nova visão em que os povos colonizados de mero objecto de representação se transformam em sujeitos da sua própria história. Em Cultura e Imperialismo , publicado em 1993, Said analisa como os intelectuais e os criadores dos povos dominados elaboram uma nova representação de si próprios e do Outro no âmbito do processo de luta e emancipação colonial. Mas apenas a livre interacção e interdependência das culturas poderá constituir uma síntese superadora do imperialismo e do nacionalismo anticolonial. Dimensão libertadora que se tornará a verdadeira missão e vocação do intelectual sem fronteiras de que Said foi um dos maiores expoentes contemporâneos.

An approach to absorptive capacity based on the Portuguese textile industry

The main purpose of this research is to identify the hidden knowledge and learning mechanisms in the organization in order to disclosure the tacit knowledge and transform it into explicit knowledge. Most firms usually tend to duplicate their efforts acquiring extra knowledge and new learning skills while forgetting to exploit the existing ones thus wasting one life time resources that could be applied to increase added value within the firm overall competitive advantage. This unique value in the shape of creation, acquisition, transformation and application of learning and knowledge is not disseminated throughout the individual, group and, ultimately, the company itself. This work is based on three variables that explain the behaviour of learning as the process of construction and acquisition of knowledge, namely internal social capital, technology and external social capital, which include the main attributes of learning and knowledge that help us to capture the essence of this symbiosis. Absorptive Capacity provides the right tool to explore this uncertainty within the firm it is possible to achieve the perfect match between learning skills and knowledge needed to support the overall strategy of the firm. This study has taken in to account a sample of the Portuguese textile industry and it is based on a multisectorial analysis that makes it possible a crossfunctional analysis to check on the validity of results in order to better understand and capture the dynamics of organizational behavior.

An approach to absorptive capacity based on the Portuguese textile industry(Final version)

The main purpose of this research is to identify the hidden knowledge and learning mechanisms in the organization in order to disclosure the tacit knowledge and transform it into explicit knowledge. Most firms usually tend to duplicate their efforts acquiring extra knowledge and new learning skills while forgetting to exploit the existing ones thus wasting one life time resources that could be applied to increase added value within the firm overall competitive advantage. This unique value in the shape of creation, acquisition, transformation and application of learning and knowledge is not disseminated throughout the individual, group and, ultimately, the company itself. This work is based on three variables that explain the behaviour of learning as the process of construction and acquisition of knowledge, namely internal social capital, technology and external social capital, which include the main attributes of learning and knowledge that help us to capture the essence of this symbiosis. Absorptive Capacity provides the right tool to explore this uncertainty within the firm it is possible to achieve the perfect match between learning skills and knowledge needed to support the overall strategy of the firm. This study has taken in to account a sample of the Portuguese textile industry and it is based on a multisectorial analysis that makes it possible a crossfunctional analysis to check on the validity of results in order to better understand and capture the dynamics of organizational behavior.

Learning and Knowledge in the Context of Absorptive Capacity

Develop a new model of Absorptive Capacity taking into account two variables namely Learning and knowledge to explain how companies transform information into knowledge

Synthesis, structure, and optical properties of an alternating calix[4]arene-based meta-linked phenylene ethynylene copolymer

Novel alternating copolymers comprising biscalix[4]arene-p-phenylene ethynylene and m-phenylene ethynylene units (CALIX-m-PPE) were synthesized using the Sonogashira-Hagihara cross-coupling polymerization. Good isolated yields (60-80%) were achieved for the polymers that show M-n ranging from 1.4 x 10(4) to 5.1 x 10(4) gmol(-1) (gel permeation chromatography analysis), depending on specific polymerization conditions. The structural analysis of CALIX-m-PPE was performed by H-1, C-13, C-13-H-1 heteronuclear single quantum correlation (HSQC), C-13-H-1 heteronuclear multiple bond correlation (HMBC), correlation spectroscopy (COSY), and nuclear overhauser effect spectroscopy (NOESY) in addition to Fourier transform-Infrared spectroscopy and microanalysis allowing its full characterization. Depending on the reaction setup, variable amounts (16-45%) of diyne units were found in polymers although their photophysical properties are essentially the same. It is demonstrated that CALIX-m-PPE does not form ground-or excited-state interchain interactions owing to the highly crowded environment of the main-chain imparted by both calix[4]arene side units which behave as insulators inhibiting main-chain pi-pi staking. It was also found that the luminescent properties of CALIX-m-PPE are markedly different from those of an all-p-linked phenylene ethynylene copolymer (CALIX-p-PPE) previously reported. The unexpected appearance of a low-energy emission band at 426 nm, in addition to the locally excited-state emission (365 nm), together with a quite low fluorescence quantum yield (Phi = 0.02) and a double-exponential decay dynamics led to the formulation of an intramolecular exciplex as the new emissive species.

Guitar solo tracker

A motivação para este trabalho vem da necessidade que o autor tem em poder registar as notas tocadas na guitarra durante o processo de improviso. Quando o músico está a improvisar na guitarra, muitas vezes não se recorda das notas tocadas no momento, este trabalho trata o desenvolvimento de uma aplicação para guitarristas, que permita registar as notas tocadas na guitarra eléctrica ou clássica. O sinal é adquirido a partir da guitarra e processado com requisitos de tempo real na captura do sinal. As notas produzidas pela guitarra eléctrica, ligada ao computador, são representadas no formato de tablatura e/ou partitura. Para este efeito a aplicação capta o sinal proveniente da guitarra eléctrica a partir da placa de som do computador e utiliza algoritmos de detecção de frequência e algoritmos de estimação de duração de cada sinal para construir o registo das notas tocadas. A aplicação é desenvolvida numa perspectiva multi-plataforma, podendo ser executada em diferentes sistemas operativos Windows e Linux, usando ferramentas e bibliotecas de domínio público. Os resultados obtidos mostram a possibilidade de afinar a guitarra com valores de erro na ordem de 2 Hz em relação às frequências de afinação standard. A escrita da tablatura apresenta resultados satisfatórios, mas que podem ser melhorados. Para tal será necessário melhorar a implementação de técnicas de processamento do sinal bem como a comunicação entre processos para resolver os problemas encontrados nos testes efectuados.

Sistema de apoio à criminologia

Este trabalho consiste no desenvolvimento de um Sistema de Apoio à Criminologia – SAC, onde se pretende ajudar os detectives/analistas na prevenção proactiva da criminalidade e na gestão dos seus recursos materiais e humanos, bem como impulsionar estudos sobre a alta incidência de determinados tipos de crime numa dada região. Historicamente, a resolução de crimes tem sido uma prerrogativa da justiça penal e dos seus especialistas e, com o aumento da utilização de sistemas computacionais no sistema judicial para registar todos os dados que dizem respeito a ocorrências de crimes, dados de suspeitos e vítimas, registo criminal de indivíduos e outros dados que fluem dentro da organização, cresce a necessidade de transformar estes dados em informação proveitosa no combate à criminalidade. O SAC tira partido de técnicas de extracção de conhecimento de informação e aplica-as a um conjunto de dados de ocorrências de crimes numa dada região e espaço temporal, bem como a um conjunto de variáveis que influenciam a criminalidade, as quais foram estudadas e identificadas neste trabalho. Este trabalho é constituído por um modelo de extracção de conhecimento de informação e por uma aplicação que permite ao utilizador fornecer um conjunto de dados adequado, garantindo a máxima eficácia do modelo.

Study of the Saldanha Massif (MAR, 36 degrees 34 ' N): Constrains from rock magnetic and geophysical data

We present a study of the magnetic properties of a group of basalt samples from the Saldanha Massif (Mid-Atlantic Ridge - MAR - 36degrees 33' 54" N, 33degrees 26' W), and we set out to interpret these properties in the tectono-magmatic framework of this sector of the MAR. Most samples have low magnetic anisotropy and magnetic minerals of single domain grain size, typical of rapid cooling. The thermomagnetic study mostly shows two different susceptibility peaks. The high temperature peak is related to mineralogical alteration due to heating. The low temperature peak shows a distinction between three different stages of low temperature oxidation: the presence of titanomagnetite, titanomagnetite and titanomaghemite, and exclusively of titanomaghemite. Based on established empirical relationships between Curie temperature and degree of oxidation, the latter is tentatively deduced for all samples. Finally, swath bathymetry and sidescan sonar data combined with dive observations show that the Saldanha Massif is located over an exposed section of upper mantle rocks interpreted to be the result of detachment tectonics. Basalt samples inside the detachment zone often have higher than expected oxidation rates; this effect can be explained by the higher permeability caused by the detachment fault activity.