964 resultados para visual method
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Laggards are the last users to adopt a product. Prior literature on user-led innovation ignores laggards’ impact on innovation. In this paper, we develop the Lag-User Method, through which laggards can generate new ideas. Through six studies with 62 teams in three countries, we apply the method to different technologies and services and present our findings to executives to get managerial insights. Findings reveal that laggards who generate new ideas (lag-users) have different perceptions of user-friendly products and different unfulfilled needs. They prefer simple products. We propose that by involving lag-users in NPD, firms can improve the effectiveness of NPD.
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PURPOSE: To determine the causes of low vision in an elderly population attended by a university visual rehabilitation service and to check for the use of prescribed optical aids. METHOD: A cross-sectional study was carried out on patients aged 60 years or over attending for the first time a university low vision service in 2001. Ophthalmic reevaluation and interview were performed by means of a structured questionnaire in 2002. RESULTS: The sample comprised 50 subjects aged between 60 and 90 years. Severe low vision (<20/200) was present in 68.0% of patients. The main cause of low vision was age-related macular degeneration (44.0%). Regarding literacy, 16.0% were illiterate and 72.0% had completed fundamental schooling. Thirty-one patients (62.0%) had been prescribed optical aids; 54.8% of these patients stated that they use them. A majority (70.6%) held a favorable opinion of these aids. CONCLUSIONS: The main cause of low vision was age-related macular degeneration. Approximately half of those receiving prescriptions reported actually using the aids in their daily activities. Making best use of residual vision in the elderly population with visual impairment is a priority, given the social context, if the independence necessary for enhanced quality of life is to be achieved.
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Diabetic neuropathy is an important complication of the disease, responsible for ulceration and amputation of the foot. Prevention of these problems is difficult mainly because there is no method to correctly access sensibility on the skin of the foot. The introduction of the Pressure-Specified Sensory Device (PSSD TM) in the last decade made possible the measurement of pressure thresholds sensed by the patient, such as touch, both static and in movement, on a continuous scale. This paper is the first in Brazil to report the use of this device to measure cutaneous sensibility in 3 areas of the foot: the hallux pulp, the calcaneus, and the dorsum, which are territories of the tibial and fibular nerves. METHOD: Non-diabetic patients were measured as controls, and 2 groups of diabetic patients - with and without ulcers - were compared. The PSSD TM was used to test the 3 areas described above. The following were evaluated: 1 PS (1-point static), 1 PD (1-point dynamic), 2 PS (2-points static), 2 PD (2-points dynamic). RESULTS: The diabetic group had poorer sensibility compared to controls and diabetics with ulcers had poorer sensibility when compared to diabetics without ulcers. The differences were statistically significant (P <.001). CONCLUSION: Due to the small number of patients compared, the results should be taken as a preliminary report.
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A argumentação centra-se na história da produção cenográfica da segunda metade do século XIX em Portugal, propondo um tratamento teórico mais abrangente, que desloque o enfoque analítico da peça de arte em si ou do carácter efémero e global da espectacularidade que tem merecido alguma atenção da historiografia contemporânea, para uma escala de cultura visual ou mesmo de visualidade, no sentido mais dilatado destas expressões. Discutindo essencialmente a problemática em torno da imagem teatral como produto do mundo oitocentista analisa-se o potencial cognitivo da série cenográfica na sua capacidade de representação e apropriações ideológicas. Para esta dialéctica concorrem as repercussões epocais do espectáculo, designadamente na regulação da vida social, na mediação de processos económicos, no combate político, e sobretudo, em modelos de percepção artística fundados nos convencionalismos cenográficos como acontece, por exemplo, na produção decorativa e arquitectónica integradas num particular campo visual ou na teatralidade actuante dos edifícios, cuja essência, em todos os casos, é devedora de uma cultura paradoxalmente centrada nos limites da caixa cénica e na infinitude emotiva do espectacular.
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The stylistic categorization of the Estado Novo has been intensely discussed by Portuguese art historians. The square Alameda Dom Afonso Henriques in Lisbon (Alameda) can be seen as paradigmatic for the architecture of power of the Estado Novo. The Alameda forms a gardened valley between two hills. There you find two prominent and highly propagandist buildings: The Instituto Superior Técnico (IST) and the Fonte Luminosa are dedicated to modern sciences and respectively to the harmonious contribution of nature to the city. The iconography of the Alameda as well as its incorporation into the propagandist use of urban planning in the 1930s and 1940s exemplify the visual politics during Salazarism. Urban planning programs intended to create cities that would preserve the character of a traditional catholic society and at the same time answer to the need to modernize the country and evoke the image of a progressive state. Thus, public buildings and urban squares such as the Alameda contributed to design a corporate image and to the ‘spirit’ of the regime.
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A pictorial field guide to the 30 species of sandfly most commonly encountered in Pará State is presented, based on the easily recognised external characters of the length of the 5th palpal segment, thoracic infuscation, abdominal colour and head and body size. In most cases this allows identification to the species. In others, especially with females, it gives an indication of the species, which may then be confirmed with data from more detailed taxanomix studies. This type of field guide helps in teaching, rapid sorting of flies prior to dissection and in acquainting visitors with the variety of species present in a given area.A rapid technique for the taxonomic sorting of unmounted, freshly killed female sandflies is required, prior to the dissection of large numbers of a particular species. Such a method is useful in areas where numerous species occur in studies on natural flagellate infections, age determination and for ecological studies. With the above points in mind a pictorial field guide has been designed that enables the identification of unmounted, unmacerated specimens of the 30 more commonly encountered species of phleboto-mine sandflies (***) in Pará State, North Brazil. It is based on the easily recognised external characters of the length of the 5th palpal segment, thoracic infuscation, ad-dominal colour and proboscis and body size.Taxonomy of male phlebotomine sandflies is based on the structure of the genitalia and, as most of this is external, a wholly external character key is readily made. Female taxonomy, however, is based on the internal character of the cibarium, pharynx and sperma thecae. In order to produce an external character key we therefore return to an unso phisticated "phlebotometry" (see Martins et al., 1978 p. 3 for review), using relative lengths of the proboscis, palpal segments and body, along with the degree of infuscation. Ihis idea is not new; indeed many sandfly specialists presently use external characters to separate certain species (H. Fraiha, R. P. Lane, P. D. Ready, D. G. Young and R. D. Ward personal communications 1983 & 1984).A key used to separate five anthropophillic sandflies by Biagi (1966), in Mexico, was based mainly on palpal segment length and infuscation. Floch and Abonnenc (1952) stressed the use of relative lengths of palpal segments in their keys to the sandflies of French Guiana, and four members of the shannoni group have been similarly separated according to the degree of infuscation by Morales et al. (1982). The use of thoracic infuscation as a reliable character seems to be gaining favour, having been used by young & Fairchild (1974) and Ready & Fraiha (1981). Indeed Chariotis 1974) showed the usefulness of thoracic infuscation to sepenate 7 anthropophillic species, during studies onvesicular stomatitis in Panama. Identification using external characters is essential for work on viral isolations from sandflies, where bulk samples of whole sandflies are used.Perhaps the major advantage of a simple visual guide is for teaching purposes. Technical staff in this lnstitute are able to identify most of the species they encounter without having to use the standard, more unwieldly (and in many cases unavailable) internal character keys, and the guides presented below have allowed rapid species sorting prior to the dissection of sandflies in our leismaniasis study areas (Ryan et at. ,1985).
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RESUMO: Os mais recentes métodos de neuro imagem tal como a Ressonância Magnética (RM) permitiram obter imagens detalhadas do cérebro humano in vivo. Essas imagens revelam, muitas vezes, achados imprevistos face ao padrão normal, com elevada propensão para os indivíduos idosos e franca coexistência com fatores de risco vascular, como característica dum processo de envelhecimento normal. Embora na última década tenham surgido várias publicações sobre este assunto, ele continua ainda pouco explicado. Um pouco por todo o mundo têm emergido os programas de prevenção da doença e promoção da saúde desenvolvidos pela Saúde Pública suportadas sobretudo pelo avanço das tecnologias médicas que resultaram, entre outros impactos, num crescimento da população idosa. Estima-se, em 2030, uma composição demográfica com 20% de indivíduos acima dos 65 anos. Neste contexto, a doença microvascular cerebral é a causa mais frequente de comprometimento cognitivo vascular no idoso sendo as características senescentes na imagem por RM do tipo lesões isquémicas da Substância Branca (Leukoaraiosis) e enfartes lacunares (Status lacunar), atrofia cerebral, gliose e acumulação excessiva de ferro nos núcleos da base. Esta tese, considerando a linha de investigação de que deriva – Ciências da Vida - especialização em Medicina Clinica - Biotecnologia, reúne e reflete sobre três vertentes ligadas à RM e interdependentes em relação a uma problemática comum. A primeira trata da caracterização da Tecnologia por Ressonância Magnética existente em Portugal, a qual inclui uma avaliação exploratória da aplicação da técnica de Difusão Anisotrópica nos estudos cerebrais. As dimensões analíticas estudadas foram a Tecnológica, Sociodemográfica e Económica. Na recolha de dados recorreu-se a várias fontes de informação e a uma metodologia exploratória faseada, validada pela triangulação dos resultados. A sua análise obedeceu a critérios de estratificação e agrupamento segundo as mesmas dimensões analíticas. Otimização da anisotropia fronto-calosa e [RM 1,5T] no idoso normal e com risco cérebro-vascular A segunda descreve o estudo anátomo – radiológico que recaiu sobre parâmetros de quantificação assente na temática do cérebro do idoso em cadáver segundo uma metodologia experimental aplicada às métricas da difusão por RM. Na terceira, e última, é apresentado o estudo técnico - radiológico para avaliação e otimização da imagem ponderada em difusão em estudos clínicos associados ao cérebro do idoso “The Usual Brain Aging” ou Envelhecimento Cerebral Normal, com base metodológica assente nos critérios e indicadores estabelecidos pelo Estudo de Imagem de Roterdão (Rotterdam Scan Study - RSS). Como principais resultados obteve-se que não existem em Portugal estruturas para avaliação dos equipamentos pesados ou Agência de Avaliação das Tecnologias da Saúde para desenvolver o importante papel da produção de estudos comparativos entre os equipamentos disponíveis no mercado, a relação preço-qualidade e a sua afetação às necessidades clínico-epidemiológicas. Constatou-se que a implementação de equipamentos de RM está fortemente assente em critérios económicos carecendo de recomendações e diretivas para o uso racionalizado destas tecnologias. Quanto a dados quantitativos concluímos que a maioria dos equipamentos está instalada em instituições privadas (80,2%); a intensidade de campo magnético mais frequente é [1,5T] com 119 equipamentos; os equipamentos estão instalados maioritariamente nos distritos de Lisboa (55 unidades) e do Porto (39 unidades); o rácio médio de equipamentos por habitante em Portugal é de 1 para 65 195 habitantes; a amplitude de gradientes com maior expressão na amostra é 30-39mT/m; a maioria dos equipamentos foi instalada no intervalo temporal [2009-2012] com 59 equipamentos; apenas 6 instituições desenvolvem investigação clinica e a maioria das bobinas para estudos de crânio são do tipo Array. O estudo de otimização da técnica da difusão revelou, quanto à avaliação dos valoresb, que os mais baixos (b=500 s/mm2 e b=1000 s/mm2), apresentam maior IS e SNR sendo esta uma boa medida referente à qualidade de imagem, no entanto, os valores-b mais elevados (b=2000 s/mm2) apresentam maior CNR e CR, face aos anteriores, o Otimização da anisotropia fronto-calosa e [RM 1,5T] no idoso normal e com risco cérebro-vascular que apesar de proporcionar inferior detalhe anatómico e consequentemente inferior qualidade de imagem, num encéfalo normal, pode auxiliar na interpretação e apresentar vantagens na identificação de lesões microvasculares sempre que persistirem dúvidas em relação ao diagnóstico diferencial de doença microvascular do tipo status lacunar ou Hiperintensidades da Substância Branca. As alterações deste parâmetro são particularmente refletidas nas diferenças da avaliação da qualidade de imagem na região fronto-calos Concluímos da avaliação quantitativa da concentração média de ferro (26Fe) em todas as faixas etárias que os núcleos da base que apresentam maior concentração são, por ordem decrescente: Substância Nigra, Globus Pallidus, Putamen, Tálamo, Núcleo Rubro e Núcleo Caudado; que existe uma predominância na concentração de ferro (26Fe) no hemisfério esquerdo e que os indivíduos do género masculino apresentam mais ferro (26Fe) que os do género feminino nas faixas etárias [30-40[, [40-50[ e [50-60[. Como principal conclusão do estudo da concentração média de ferro em relação à idade destacamos que a concentração média de ferro (26Fe) é superior nos grupos etários superiores, logo aumenta com a idade, sobretudo na Substância Nigra e no Núcleo Lenticular. No estudo técnico-radiológico encontrámos evidências do aumento da difusibilidade da água na substância branca subcortical dos sujeitos idosos comparativamente aos mais jovens. Uma relação idêntica foi avaliada nos tálamos. O aumento relacionado com a idade parece ser predominantemente observado em doentes com mais de 65 anos de idade o que pode refletir alterações estruturais ligeiras associados ao envelhecimento normal. Os resultados indicam que a análise quantitativa das imagens ponderadas em difusão fornece informações, sobre a estrutura do cérebro, as quai s não estão disponíveis apenas por inspeção visual, tanto nas imagens ponderadas em difusão como em outras sequências de aplicação clínica de rotina. Para fazer face às desvantagens dos sistemas de quantificação das HSB os quais são dispendiosos, complexos, requererem tecnologia e formação específicas, recomendamos que a aplicação automatizada GUIAL, desenvolvida ao longo do nosso trabalho é de utilização elementar e prática para que seja introduzida nos sistemas de aquisição de imagem por RM com o fim de integrar o processamento de imagem nos indivíduos portadores de fatores de risco vascular. A avaliação do ADC, nesta amostra, permitiu concluir que a variação desta variável é explicada estatisticamente pela existência da condição clínica de status lacunar em ambos os hemisférios ou por outras palavras, o status lacunar influencia o valor de ADC. Embora uma pequena percentagem da variação do ADC seja explicada pelo género, o ADC nos homens foi superior ao das mulheres o que não nos surpreende, pois são também os homens onde a frequência de doença microvascular se revelou mais expressiva. Os valores do ADC, globalmente, entre os hemisférios cerebrais não mostraram alterações exceto na SB entre os idosos e não idosos. A SB da região frontal mostrou valores diminuídos na anisotropia e isotropia face às restantes áreas anatómicas. Os estudos indicam que na idade avançada existe uma maior predisposição para suscetibilidades de estrutura com status de desconexão. A classificação das HSB foi superior em indivíduos mais velhos e com status lacunar, e em menor quantidade (inferior rating de classificação) nos indivíduos idosos sem status lacunar. As alterações volumétricas foram mais frequentes no homem do que na mulher, presumivelmente devido à associação com a elevada classificação de status lacunar. Um aumento do índice de Evan correspondeu, neste estudo, ao aumento das HSB, à diminuição do volume cerebral total, à expansão ventrículo-sulcal frontal e ao aumento da medida do ângulo caloso. Estes resultados foram agravados pela classificação elevada de status lacunar nos indivíduos que apresentaram indícios de doença de pequenos vasos, com manifesto aumento dos espaços de Virchow-Robin,enfartes lacunares ou HSB. Esses resultados foram mais expressivos no género masculino do que no feminino revelando uma maior vulnerabilidade sobretudo na atrofia frontal nos homens. Por sua vez as dimensões do Corpo Caloso tornaram-se reduzidas devido à compressão dos ventrículos laterais e terceiro ventrículo. Estes indicadores tiveram expressão particularmente nos indivíduos com mais de 65 anos. ---------------------------------------------------------------------------------------------ABSTRACT: The latest neuroimaging methods, such as Magnetic Resonance Imaging (MRI), have enabled detailed images of in vivo human brain. These images reveal often unexpected findings related to the normal pattern, with high predisposition for the elderly people with forthright coexistence with vascular risk factors such as characteristics of a normal aging process. Although it has been, in the last decade, several publications on this subject, it is still little explained. All over the world have emerged disease prevention programs and health promotion developed by the Public Health sector, supported mainly by the advancement of medical technologies that have resulted, among other impacts, in a growing of the elderly population. It is estimated, in 2030, a demographic composition with 20% o people over 65 years. In this context, microvascular disease is the most common cause of cognitive vascular impairment in the elderly and senescent characteristics in the MRI trough ischemic lesions of the white matter (Leukoaraiosis) and lacunar infarcts (lacunar status), cerebral atrophy, gliosis and iron accumulation in the basal ganglia in excess.This thesis, considering the research line that stems - Life Sciences - specialization in Clinical Medicine, Biotechnology, gathers and reflects on three aspects linked to MR, interdependent and related to a common problem. The first deals with the Magnetic Resonance Technology characterization in Portugal, which includes an exploratory evaluation of the implementation of Anisotropic Diffusion technique in brain studies. The analytical dimensions studied were the Technologic, Socio-demographic and Economics. Collecting data was supported by different sources of information and was applied an exploratory methodology whose results were validated by triangulation. The research method was grouped and stratified criteria under the same analytical dimensions. The second describes the anatomical study - which was focused on radiological measurement parameters, based on the brain’s specimen under an experimental methodology applied to MRI diffusion metrics. Radiological evaluation and optimization of the weighted image diffusion in clinical studies were associated with the brain of the elderly "The Usual Brain Aging" with methodological basis based on established criteria and indicators by Rotterdam Scan Study (RSS). The main results obtained reveal the inexistence frameworks in Portugal for evaluation of equipments or Agency of Health Technology to produce studies comparing the equipment available on the market, the value for money and its allocation to clinical and epidemiological needs. It was found that the implementation of MRI equipment is strongly based on economic criteria lacking recommendations and guidelines for the rationalized use of these technologies. As the quantitative data we conclude that most of the scanners are located in private clinical institutions (80,2%); the most frequent magnetic field intensity is [1.5T] with 119 scanners; the scanners are mainly installed in Lisbon (55 units) and Porto (39 units) districts; the average ratio of equipment per capita in Portugal is 1 to 65 195 people; the gradient power with higher expression in the sample is 30-39mT / m;most of the scanners were installed in the years range [2009-2012 years] with 59 equipment; only 6 clinical placements develop clinical research and the most coils for brain studies are of Array type. The optimization study of diffusion technique revealed, as the assessment of the bvalues, the lower (b = 500 s / mm2 and b = 1000 s / mm 2), promotes an increase in the SI and SNR being this measure related to a higher image quality, however the highest b values (b = 2000 s / mm 2) have a higher CNR (Contrast to Noise-Ratio) and CR (Contrast Ratio), compared to the previous ones. This may provide less anatomical details and, thus, ower image quality, of a normal brain, however can help the interpretation and have advantages in identifying microvascular injuries when doubts persist regarding the differential diagnosis of microvascular disease of lacunar or WMH (White Matter Hyperintensities) status type. Changes on this parameter are Otimização da anisotropia fronto-calosa e [RM 1,5T] no idoso normal e com risco cérebro-vascular particularly reflected in the differences of image quality evaluation in the frontocallosum anatomical area. We conclude from the quantitative assessment of the average concentration of iron (26Fe), in all age groups to the basal ganglia, that the higher concentrations are, in descending order: Nigral Substantia, Globus pallidus, Putamen, Thalamus, Rubio nucleus and Caudate nucleus; that there is a predominance in the concentration of iron (26Fe) in the left hemisphere and that male gender show higher iron (26Fe) level tha females, in the age groups [30-40 [[40-50 [and [50- 60 [. Regarding a main conclusion of the mean concentration study of iron, in terms of age we point out that the average concentration of iron (26Fe) is higher among older groups and increases with age, especially in Nigral Substantia and Lenticular Nucleus. On the technical and radiological study we found evidence of an increased in water /diffusivity in the ubcortical white matter of the elderly compared with younger subjects. A similar relationship was assessed in the Thalamus. The increase agerelated seems to be predominantly observed in patients over 65 years which may reflect minor structural changes associated with normal aging. The results indicate that quantitative analysis of diffusion weighted imaging can provide information about the structure of the brain which is not reached only by visual inspection or standard sequences applied in clinical routine. To address the disadvantages the systems of quantification of WMH which the authors state that are costly, complex, require specific technology and training, we recommend that the automated application GUIAL, developed over our work is basic and practical to use and to be introduced in MR image systems acquisition in order to integrate image processing in patients with vascular risk factors. The evaluation of the ADC showed that its variation is statistically explained by the existence of the medical condition of lacunar status, in both hemispheres, or in other words, the lacunar status influences the ADC value. Although a small percentage of the ADC variation is explained by gender, the ADC in men was higher than women which Otimização da anisotropia fronto-calosa e [RM 1,5T] no idoso normal e com risco cérebro-vascular do not surprise us, since they are also men where the frequency of microvasculardisease has proved more significant. The values of ADC, overall, between the cerebral hemispheres showed no changes but were different in WM among the elderly and non-elderly subjects.The WM's forehead showed decreased values in anisotropy and isotropy face the other anatomical areas. The studies indicate that in old age there is a greater tendency to higher susceptibility to disconnection- status framework. The classification of WMH was higher in elderly people and lacunar status, and fewer (lower classification rating) in the elderly without lacunar status. volumetric changes were more frequent in men than in women, most probably because of its association with high lacunar status rating. An increase of Evan index corresponded, in this study, to an increase in WMH, to a decreased of total brain volume, to a ventricle sulcal frontal and callous angle expansion. These results were wound up by high ranking of lacunar status in subjects who had small vessel disease, clear increase in spaces of Virchow-Robin, lacunar infarctions or WMH. These results were more significant in males than in females revealing vulnerability particularly in the frontal atrophy in men. In turn the size of Corpus Callosum because reduced due to the compression of the lateral and third ventricles. These indicators had expression particularly in individuals over 65 years.
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Doctoral Program in Computer Science
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Injectable biomaterials with in situ cross-linking reactions have been suggested to minimize the invasiveness associated with most implantation procedures. However, problems related with the rapid liquid-to-gel transition reaction can arise because it is difficult to predict the reliability of the reaction and its end products, as well as to mitigate cytotoxicity to the surrounding tissues. An alternative minimally invasive approach to deliver solid implants in vivo is based on injectable microparticles, which can be processed in vitro with high fidelity and reliability, while showing low cytotoxicity. Their delivery to the defect can be performed by injection through a small diameter syringe needle. We present a new methodology for the continuous, solvent- and oil-free production of photopolymerizable microparticles containing encapsulated human dermal fibroblasts. A precursor solution of cells in photo-reactive PEG-fibrinogen (PF) polymer was transported through a transparent injector exposed to light-irradiation before being atomized in a jet-in-air nozzle. Shear rheometry data provided the cross-linking kinetics of each PF/cell solution, which was then used to determine the amount of irradiation required to partially polymerize the mixture prior to atomization. The partially polymerized drops fell into a gelation bath for further polymerization. The system was capable of producing cell-laden microparticles with high cellular viability, with an average diameter of between 88.1 µm to 347.1 µm and a dispersity of between 1.1 and 2.4, depending on the parameters chosen.
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Nowadays, road accidents are a major public health problem, which increase is forecasted if road safety is not treated properly, dying about 1.2 million people every year around the globe. In 2012, Portugal recorded 573 fatalities in road accidents, on site, revealing the largest decreasing of the European Union for 2011, along with Denmark. Beyond the impact caused by fatalities, it was calculated that the economic and social costs of road accidents weighted about 1.17% of the Portuguese gross domestic product in 2010. Visual Analytics allows the combination of data analysis techniques with interactive visualizations, which facilitates the process of knowledge discovery in sets of large and complex data, while the Geovisual Analytics facilitates the exploration of space-time data through maps with different variables and parameters that are under analysis. In Portugal, the identification of road accident accumulation zones, in this work named black spots, has been restricted to annual fixed windows. In this work, it is presented a dynamic approach based on Visual Analytics techniques that is able to identify the displacement of black spots on sliding windows of 12 months. Moreover, with the use of different parameterizations in the formula usually used to detect black spots, it is possible to identify zones that are almost becoming black spots. Through the proposed visualizations, the study and identification of countermeasures to this social and economic problem can gain new grounds and thus the decision- making process is supported and improved.
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The experimental evaluation of viscoelastic properties of concrete is traditionally made upon creep tests that consist in the application of sustained loads either in compression or in tension. This kind of testing demands for specially devised rigs and requires careful monitoring of the evolution of strains, whereas assuring proper load constancy. The characterization of creep behaviour at early ages offers additional challenges due to the strong variations in viscoelastic behaviour of concrete during such stages, demanding for several testing ages to be assessed. The present research work aims to assist in reducing efforts for continuous assessment of viscoelastic properties of concrete at early ages, by application of a dynamic testing technique inspired in methodologies used in polymer science: Dynamic Mechanical Analyses. This paper briefly explains the principles of the proposed methodology and exhibits the first results obtained in a pilot application. The results are promising enough to encourage further developments.
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Sustainability is frequently defined by its three pillars: economically viable, socially equitable, and environmentally bearable. Consequently the evaluation of the sustainability of any decision, public or private, requires information on these three dimensions. This paper focuses on social sustainability. In the context of renewable energy sources, the examination of social sustainability requires the analysis of not only the efficiency but also the equity of its welfare impacts. The present paper proposes and applies a methodology to generate the information necessary to do a proper welfare analysis of the social sustainability of renewable energy production facilities. This information is key both for an equity and an efficiency analysis. The analysis focuses on the case of investments in renewable energy electricity production facilities, where the impacts on local residents’ welfare are often significantly different than the welfare effects on the general population. We apply the contingent valuation method to selected facilities across the different renewable energy power plants located in Portugal and conclude that local residents acknowledge differently the damage sustained by the type, location and operation of the plants. The results from these case studies attest to the need of acknowledging and quantifying the negative impacts on local communities when assessing the economic viability, social equity and environmental impact of renewable energy projects.
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The diagnosis of historic masonry walls is an intricate and complex field and has been an object of research for many years. This paper aims to propose practical methodologies for the diagnosis of historic masonry walls, specifically based on their typological characteristics. In order to develop such procedures, information relating to historic masonry typologies in Portugal, classified as rural, urban and military was gathered and techniques for the assessment of historic masonry were studied. All information was integrated to develop a pattern typology oriented methodology. Developed methodology was tested and validated in a small diagnosis campaign carried out in the Guimarães Castle. Methodology was proven to be advantageous and although the study is limited and focused on the Portuguese architectural specificities, it still holds global classifications, and therefore can be useful for any diagnosis procedure of a historic masonry wall.
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One of the most popular approaches to path planning and control is the potential field method. This method is particularly attractive because it is suitable for on-line feedback control. In this approach the gradient of a potential field is used to generate the robot's trajectory. Thus, the path is generated by the transient solutions of a dynamical system. On the other hand, in the nonlinear attractor dynamic approach the path is generated by a sequence of attractor solutions. This way the transient solutions of the potential field method are replaced by a sequence of attractor solutions (i.e., asymptotically stable states) of a dynamical system. We discuss at a theoretical level some of the main differences of these two approaches.
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A conventional method for seismic strengthening of masonry walls is externally application of reinforced concrete layer (shotcrete). However, due to the lack of analytical and experimental information on the behavior of strengthened walls, the design procedures are usually followed based on the empirical relations. Using these design procedures have resulted in massive strengthening details in retrofitting projects. This paper presents a computational framework for nonlinear analysis of strengthened masonry walls and its versatility has been verified by comparing the numerical and experimental results. Based on the developed numerical model and available experimental information, design relations and failure modes are proposed for strengthened walls in accordance with the ASCE 41 standard. Finally, a sample masonry structure has been strengthened using the proposed and available conventional methods. It has been shown that using the proposed method results in lower strengthening details and appropriate (ductile) failure modes