845 resultados para exploratory design methods
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In this paper we propose the use of the least-squares based methods for obtaining digital rational approximations (IIR filters) to fractional-order integrators and differentiators of type sα, α∈R. Adoption of the Padé, Prony and Shanks techniques is suggested. These techniques are usually applied in the signal modeling of deterministic signals. These methods yield suboptimal solutions to the problem which only requires finding the solution of a set of linear equations. The results reveal that the least-squares approach gives similar or superior approximations in comparison with other widely used methods. Their effectiveness is illustrated, both in the time and frequency domains, as well in the fractional differintegration of some standard time domain functions.
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Dissertação apresentada como requisito parcial para obtenção do grau de Mestre em Ciência e Sistemas de Informação Geográfica
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The participation of the Fraunhofer Institute for Manufacturing Engineering and Automation IPA (Stuttgart, Germany) and the companies User Interface Design GmbH (Ludwigsburg, Germany) plus MLR System GmbH (Ludwigsburg, Germany) enabled the research and findings presented in this paper; we would like to namely mention Birgit Graf and Theo Jacobs (Fraunhofer IPA) furthermore Peter Klein and Christiane Hartmann (User Interface Design GmbH).
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Glass fibre-reinforced plastics (GFRP), nowadays commonly used in the construction, transportation and automobile sectors, have been considered inherently difficult to recycle due to both: cross-linked nature of thermoset resins, which cannot be remolded, and complex composition of the composite itself, which includes glass fibres, matrix and different types of inorganic fillers. Presently, most of the GFRP waste is landfilled leading to negative environmental impacts and supplementary added costs. With an increasing awareness of environmental matters and the subsequent desire to save resources, recycling would convert an expensive waste disposal into a profitable reusable material. There are several methods to recycle GFR thermostable materials: (a) incineration, with partial energy recovery due to the heat generated during organic part combustion; (b) thermal and/or chemical recycling, such as solvolysis, pyrolisis and similar thermal decomposition processes, with glass fibre recovering; and (c) mechanical recycling or size reduction, in which the material is subjected to a milling process in order to obtain a specific grain size that makes the material suitable as reinforcement in new formulations. This last method has important advantages over the previous ones: there is no atmospheric pollution by gas emission, a much simpler equipment is required as compared with ovens necessary for thermal recycling processes, and does not require the use of chemical solvents with subsequent environmental impacts. In this study the effect of incorporation of recycled GFRP waste materials, obtained by means of milling processes, on mechanical behavior of polyester polymer mortars was assessed. For this purpose, different contents of recycled GFRP waste materials, with distinct size gradings, were incorporated into polyester polymer mortars as sand aggregates and filler replacements. The effect of GFRP waste treatment with silane coupling agent was also assessed. Design of experiments and data treatment were accomplish by means of factorial design and analysis of variance ANOVA. The use of factorial experiment design, instead of the one factor at-a-time method is efficient at allowing the evaluation of the effects and possible interactions of the different material factors involved. Experimental results were promising toward the recyclability of GFRP waste materials as polymer mortar aggregates, without significant loss of mechanical properties with regard to non-modified polymer mortars.
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Volatile organic compounds are a common source of groundwater contamination that can be easily removed by air stripping in columns with random packing and using a counter-current flow between the phases. This work proposes a new methodology for column design for any type of packing and contaminant which avoids the necessity of an arbitrary chosen diameter. It also avoids the employment of the usual graphical Eckert correlations for pressure drop. The hydraulic features are previously chosen as a project criterion. The design procedure was translated into a convenient algorithm in C++ language. A column was built in order to test the design, the theoretical steady-state and dynamic behaviour. The experiments were conducted using a solution of chloroform in distilled water. The results allowed for a correction in the theoretical global mass transfer coefficient previously estimated by the Onda correlations, which depend on several parameters that are not easy to control in experiments. For best describe the column behaviour in stationary and dynamic conditions, an original mathematical model was developed. It consists in a system of two partial non linear differential equations (distributed parameters). Nevertheless, when flows are steady, the system became linear, although there is not an evident solution in analytical terms. In steady state the resulting ODE can be solved by analytical methods, and in dynamic state the discretization of the PDE by finite differences allows for the overcoming of this difficulty. To estimate the contaminant concentrations in both phases in the column, a numerical algorithm was used. The high number of resulting algebraic equations and the impossibility of generating a recursive procedure did not allow the construction of a generalized programme. But an iterative procedure developed in an electronic worksheet allowed for the simulation. The solution is stable only for similar discretizations values. If different values for time/space discretization parameters are used, the solution easily becomes unstable. The system dynamic behaviour was simulated for the common liquid phase perturbations: step, impulse, rectangular pulse and sinusoidal. The final results do not configure strange or non-predictable behaviours.
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Trihalomethanes (THMs) are widely referred and studied as disinfection by-products (DBPs). The THMs that are most commonly detected are chloroform (TCM), bromodichloromethane (BDCM), chlorodibromomethane (CDBM), and bromoform (TBM). Several studies regarding the determination of THMs in swimming pool water and air samples have been published. This paper reviews the most recent work in this field, with a special focus on water and air sampling, sample preparation and analytical determination methods. An experimental study has been developed in order to optimize the headspace solid-phasemicroextraction (HS-SPME) conditions of TCM, BDCM, CDBM and TBM from water samples using a 23 factorial design. An extraction temperature of 45 °C, for 25min, and a desorption time of 5 min were found to be the best conditions. Analysis was performed by gas chromatography with an electron capture detector (GC-ECD). The method was successfully applied to a set of 27 swimming pool water samples collected in the Oporto area (Portugal). TCM was the only THM detected with levels between 4.5 and 406.5 μg L−1. Four of the samples exceeded the guideline value for total THMs in swimming pool water (100 μgL−1) indicated by the Portuguese Health Authority.
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Hyperspectral instruments have been incorporated in satellite missions, providing large amounts of data of high spectral resolution of the Earth surface. This data can be used in remote sensing applications that often require a real-time or near-real-time response. To avoid delays between hyperspectral image acquisition and its interpretation, the last usually done on a ground station, onboard systems have emerged to process data, reducing the volume of information to transfer from the satellite to the ground station. For this purpose, compact reconfigurable hardware modules, such as field-programmable gate arrays (FPGAs), are widely used. This paper proposes an FPGA-based architecture for hyperspectral unmixing. This method based on the vertex component analysis (VCA) and it works without a dimensionality reduction preprocessing step. The architecture has been designed for a low-cost Xilinx Zynq board with a Zynq-7020 system-on-chip FPGA-based on the Artix-7 FPGA programmable logic and tested using real hyperspectral data. Experimental results indicate that the proposed implementation can achieve real-time processing, while maintaining the methods accuracy, which indicate the potential of the proposed platform to implement high-performance, low-cost embedded systems, opening perspectives for onboard hyperspectral image processing.
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RESUMO - O cancro da mama é uma preocupação da saúde pública a nível mundial, pela sua incidência, mortalidade e custos económicos associados. As terapias utilizadas no seu tratamento, embora eficazes, conduzem a alterações de todas as dimensões da Qualidade de Vida (QdV) da mulher com cancro da mama. A garantia de uma qualidade de serviço prestado deve ser uma prioridade das organizações de saúde, sendo a QdV uma medida de resultado. Partindo do pressuposto que em Portugal existe uma diferença potencial na forma como as mulheres com cancro da mama recebem o apoio por parte da fisioterapia, importa saber se a fisioterapia tem ou não influência na QdV da mulher com cancro da mama, o que, no caso de ser afirmativo, poderá constituir uma mais-valia para a qualidade do serviço prestado em oncologia. O Objectivo deste trabalho é construir um modelo de análise no sentido de responder à questão inicial de investigação: “Será que a fisioterapia contribui para a melhoria da Qualidade de Vida das mulheres com cancro da mama submetidas a cirurgia e outras terapias oncológicas?”. Neste sentido o trabalho de projecto dividiu-se por etapas. Inicialmente foi realizado um enquadramento teórico, através de uma revisão de literatura e da realização de entrevistas exploratórias, permitindo desta forma ter um conhecimento actual das temáticas que definem as variáveis e o objecto de estudo. Na etapa seguinte, foi feita uma análise crítica sobre o conhecimento actual do tema em estudo, que permitiu definir as variáveis a estudar, escolher o instrumento de medida a utilizar, ter conhecimento dos procedimentos a seguir. Após a definição do objectivo geral (avaliar se a fisioterapia tem influência na QdV das mulheres submetidas a cirurgia e outras terapias oncológicas) e dos objectivos específicos, iniciou-se o delineamento da metodologia tida como adequada para responder às questões de investigação levantadas (tipo de estudo, as variáveis, a unidade de análise, os métodos e técnicas de recolha de dados, os procedimentos e a metodologia de tratamento de dados). No âmbito do trabalho de projecto está definida a colocação em campo de um caso de estudo efectivo que permita dar um contributo real no delineamento da metodologia. Neste trabalho optou-se pela realização de um estudo piloto, que se enquadra nos procedimentos da metodologia e que teve por objectivo retirar algumas conclusões sobre: a aplicabilidade do instrumento de medida; os tempos definidos para a recolha de dados; as características sociodemográficas e clínicas da amostra; as questões de investigação levantadas. O estudo piloto consistiu num estudo pré-experimental, com uma amostra de 35 indivíduos, submetidos a cirurgia a cancro da mama e a outras terapias oncológicas. Foram avaliadas as dimensões do bem-estar físico e actividades quotidianas, bem-estar psicológico, relações sociais, sintomas e características sociodemográficas/clínicas, no início do tratamento individual de fisioterapia e no momento de alta. Utilizou-se como instrumento de medida o questionário EORTC QLQ–30 e o seu questionário complementar EORTC QLQ–23. Tendo sido construída uma ficha para recolha de dados sociodemográficos e clínicos. A significância estatística foi aceite para valores de p<0,05. Para comparação entre grupos e evolução dentro de cada grupo aplicou-se o teste t-student e o teste de Mann-Whitney. A análise dos resultados do estudo piloto permitiu verificar que: - O instrumento de medida proposto (questionário EORTC QLQ30 e BR23) mostrou ser de fácil aplicação, não tendo existido dificuldade por parte das doentes no seu preenchimento. Não houve problemas no cálculo dos scores e na sua interpretação; - Parte considerável das mulheres com cancro da mama será submetida a protocolos que se poderão prolongar por vários meses após a cirurgia (ex: QT+RT+HT). Esta realidade leva-nos a propor que sejam realizados vários momentos de avaliação, para que possam ser avaliadas as dimensões da QdV ao longo dos diferentes protocolos de tratamentos. Pensamos que o ideal seria a realização de 4 momentos de avaliação (3 a 4 semanas após a cirurgia, 3 meses, 6 meses e 9 meses após cirurgia). Sugerimos também que o estudo proposto seja realizado com uma amostra de maior dimensão; - O estudo piloto como recorreu a uma metodologia pré-experimental (ausência de grupo de controlo e apenas dois momentos de avaliação), não permite a consistência dos resultados; no entanto os resultados obtidos podem constituir um indicador de que a fisioterapia tem influência nas diferentes dimensões da QdV da mulher com cancro da mama submetida a cirurgia e a outras terapias oncológicas, podendo constituir uma mais-valia para a qualidade do serviço prestado em oncologia. Os resultados do estudo piloto permitiram redefinir a metodologia tida como adequada para responder à questão de investigação inicial. Apresentamos de seguida a mesma: Estudo quase-experimental, sendo a amostra constituída por dois grupos de 60 mulheres cada, submetidas a cirurgia a cancro da mama e a outras terapias oncológicas. O grupo experimental será submetido a tratamentos individuais de fisioterapia. Serão avaliadas as dimensões do bem-estar físico e actividades quotidianas, bem-estar psicológico, relações sociais e sintomas. A recolha de dados será realizada 3 semanas, 3 meses, 6 meses e 9 meses após a cirurgia. Como instrumento de medida será utilizado o questionário EORTC QLQ–30 e o seu questionário complementar EORTC QLQ–23, serão também recolhidos dados sociodemográficos e clínicos. A significância estatística será aceite para valores de p<0,05. Para comparação entre grupos e evolução dentro de cada grupo serão utilizados testes paramétricos e não paramétricos. A realização de um estudo que seguisse a metodologia acima referida permitiria uma maior consistência dos resultados, podendo eventualmente existir a confirmação de que a fisioterapia pode ter influência na QdV da mulher submetida a cirurgia a cancro da mama e a outras terapias oncológicas. A evidência de que a fisioterapia tem influência na QdV da mulher com cancro da mama, e o facto de a QdV ser um indicador da qualidade do serviço prestado em oncologia, poderão constituir um agente facilitador para a mudança na gestão de recursos humanos em organizações de saúde com a valência de oncologia, levando a uma alteração dos padrões de prática na área da fisioterapia em oncologia em Portugal, que poderá conduzir a uma melhor qualidade de serviço prestado ao doente oncológico. ----- ABSTRACT - Breast Cancer is a worldwide public health concern due to the incidence, mortality and economic costs associated. Although effective, therapies used in its treatment lead to changes in all Quality of Life (QoL) dimensions of a woman suffering from Breast Cancer. QoL is an outcome measure, and the insurance of quality of care provided should be a priority to health organizations. Taking into consideration that in Portugal there is a potential difference in the way women with Breast Cancer are provided with physical therapy, it is important to know whether physical therapy does or does not influence the QoL of women with breast cancer. If it does, it will lead to a health care quality improvement to cancer patients. The goal of the following study is to build an analysis model in order to answer the initial investigation question: “Does Physical Therapy contribute to enhance the Quality of Life of women with breast cancer who underwent surgery and other oncology treatments?” The project was divided in different stages. Initially, a literature revision was elaborated and exploratory interviews were held, which allowed an actual knowledge of the themes that define the variables and the object of study. The next stage included a critical analysis of the theme, which allowed the definition of variables of study, the choice of instrument of measure and the acquisition of some knowledge on how to proceed. After the definition of the general goal (to evaluate the influence of physical therapy on the QoL of women with breast cancer who underwent surgery and other oncology treatments) and specific goals, the choice of a right methodology took place, in order to answer the investigation questions (type of study, variables, unit analysis, methods and techniques on data collection, procedures and data treatment). In the scope of the project, it is decided to put out on the field an effective case-study which assures a real contribution on the choice of te methodology. In this particular work, there was a pilot study, included in the methodology procedures, with the goal of obtaining conclusions on the applicability of the instrument of measure; the length of time to collect data, the socio-demographic and clinical characteristics of the sample; the investigation questions. The pilot study consisted on a one group pretest-postest design, with a sample of 35 individuals who underwent surgery and other oncology treatments. Dimensions such as physical well-being and everyday life activities, psychological well-being, social relationships, symptoms and socio-demographical/clinical characteristics were assessed at the beginning of physical therapy individual treatment and at the moment of release. The instrument of measure used was the EORTC QLQ–30 questionnaire and its complementary questionnaire EORTC QLQ–23. A chart was made in order to collect socio-demographic and clinical data. Statistic significance was accepted for values of p<0,05. To compare between groups and to detect the evolution within each group, the t-student test and the Mann-Whitney test were applied. The outcome analysis of the pilot study allowed to verify that: - The instrument of measure proposed (EORTC QLQ30 and BR23) was easy to apply, and the subjects did not show any difficulty in filling it up. There was also no problem on calculating the scores or interpreting them; - A considerable part of the women with breast cancer will be submitted to protocols that may occur throughout several months after surgery (e.g., QT+RT+HT). This reality leads us to suggest several moments of assessment of the QoL dimensions in various moments of the different protocol treatments. We consider that the ideal number of evaluations would be 4 (3/4 weeks, 3 months, 6 months and 9 months after surgery). We also suggest the use of a larger sample; - Since the pilot study resorted to a one group pretest-postest design (there is an absence of control group and only two moments of assessment), there is no consistency of outcome. However, the results obtained indicate that physical therapy influences the dimensions of QoL on women with breast cancer who underwent surgery and other oncology treatments, which may be an asset to the quality of care provided to cancer patients. The outcome of the pilot study allowed to redefine the methodology given as adequate to answer the initial investigation question. Our suggestion is as follows: quasi-experimental design, with a sample of 120 subjects (2 groups of 60 women) with breast cancer who underwent surgery and other oncology treatments. The experimental group will be submitted to individual treatments of physical therapy. Dimensions such as physical well-being and everyday life activities, psychological well-being, social relationships and symptoms will be assessed. The collection of data will occur at 3 weeks, 3 months, 6 months and 9 months after surgery. The instrument of measure is the EORTC QLQ–30 questionnaire and its complementary questionnaire EORTC QLQ–23, and social-demographic and clinical information will also be collected. The statistic significance will be accepted for values of p<0,05. Parametric and non-parametric tests will be used to compare between groups and to detect the evolution within each group. Carrying out a study that followed the methodology discussed above would allow a better consistency of results, possibly enabling the confirmation that physical therapy influences the QoL of women with breast cancer who underwent surgery and other oncology treatments. The evidence that physical therapy influences the QoL of women with breast cancer, and the fact that QoL is an indicator of quality of care provided to cancer patients, may work as a facilitating agent in the change of human resources management in health organizations associated to oncology, which will lead to a change in oncology physical therapy practice patterns in Portugal, guiding to a health care quality improvement to cancer patients.
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Enterprise and Work Innovation Studies,6,IET, pp.9-51
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Ergonomic interventions such as increased scheduled breaks or job rotation have been proposed to reduce upper limb muscle fatigue in repetitive low-load work. This review was performed to summarize and analyze the studies investigating the effect of job rotation and work-rest schemes, as well as, work pace, cycle time and duty cycle, on upper limb muscle fatigue. The effects of these work organization factors on subjective fatigue or discomfort were also analyzed. This review was based on relevant articles published in PubMed, Scopus and Web of Science. The studies included in this review were performed in humans and assessed muscle fatigue in upper limbs. 14 articles were included in the systematic review. Few studies were performed in a real work environment and the most common methods used to assess muscle fatigue were surface electromyography (EMG). No consistent results were found related to the effects of job rotation on muscle activity and subjective measurements of fatigue. Rest breaks had some positive effects, particularly in perceived discomfort. The increase in work pace reveals a higher muscular load in specific muscles. The duration of experiments and characteristics of participants appear to be the factors that most have influenced the results. Future research should be focused on the improvement of the experimental protocols and instrumentation, in order to the outcomes represent adequately the actual working conditions. Relevance to industry: Introducing more physical workload variation in low-load repetitive work is considered an effective ergonomic intervention against muscle fatigue and musculoskeletal disorders in industry. Results will be useful to identify the need of future research, which will eventually lead to the adoption of best industrial work practices according to the workers capabilities.
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Two passive methods in the assessment of intradomiciliary infestation by Rhodnius ecuadoriensis were tested: (i) the Gomes Nuñez sensor box (GN), (ii) sheets of white typing paper and (iii) one active timed manual method. The study was carried out in the Alto Chicama River Valley, Province of Gran Chimú, Department of La Libertad. The study design consisted of an initial searching of triatomines inside of the domestic environment by the manual capture active procedure (man/hour) covering all the studied houses. Then, matched pairs of GN boxes and paper sheets were simultaneously installed in the bedrooms of 207 households distributed in 19 localities. A comparative prospective trial of these passive detection devices were monitored at 2, 4 and, finally 6 months follow-up. Parasitological Trypanosoma rangeli and/or T. cruzi infections were investigated in two houses with high level of infestation by R. ecuadoriensis. 16.9% of the 207 households investigated by an initial active manual method were infested with R. ecuadoriensis. The proportion of infested houses fluctuated from 6.2 to 55.5% amongst the 19 localities investigated. T. rangeli natural infection was detected in R. ecuadoriensis specimens collected in two households. Parasite rates in the bugs ranged from 16.6 to 21.7% respectively. The most striking fact was an average rate of salivary gland infection ranging from 7.4 to 8.3%. At the end of the sixth month period, a cumulative incidence of 31.4% of positive GN boxes against 15.9% for paper sheets was recorded. All three methods combined detected domestic infestation in 129 (62.3%) of the 207 houses studied in the 19 localities. The range of houses infested varies from 6.7% to 92.9%. In areas with low bug density infestation rates, the methodology experienced in our studies, seems to be the best choice for investigations on domestic R. ecuadoriensis populations.
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Currently excessive fossil fuel consumption has become a serious problem. People are searching for new solutions of energy production and there are several options to obtain alternative sources of energy without further devastating the already destroyed environment. One of these solutions is growing microalgae, from which biodiesel can be obtained. The microalgae production is a growing business because of its many useful compounds. In order to collect these compounds microalgae must first be harvested and then dried. Nowadays the solutions used for drying use too much energy and therefore are too expensive and not sustainable. The goal of this project, one of the possible choices during the EPS@ISEP 2013 Spring, was to develop a solar microalgae dryer. The multinational team involved in its development was composed of five students, from distinct countries and fields of study, and was the responsible for designing a solar microalgae dryer prototype for the microalgae laboratory of the chemical engineering department at ISEP, suitable for future tests and incorporating control process (in order not to destroy the microalgae during the drying process). The solar microalgae dryer was built to work as a distiller that gets rid of the excess water from the microalgae suspension. This paper presents a possible solution for this problem, the steps to create the device to harvest the microalgae by drying them with the use of solar energy (also used as an energy source for the solar dryer control system), the technologies used to build the solar microalgae dryer, and the benefits it presents compared to current solutions. It also presents the device from the ethical and sustainable viewpoint. Such alternative to already existing methods is competitive as far as energy usage is concerned.
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The design of an Autonomous Surface Vehicle for operation in river and estuarine scenarios is presented. Multiple operations with autonomous underwater vehicles and support to AUV missions are one of the main design goals in the ROAZ system. The mechanical design issues are discussed. Hardware, software and implementation status are described along with the control and navigation system architecture. Some preliminary test results concerning a custom developed thruster are presented along with hydrodynamic drag calculations by the use of computer fluid dynamic methods.
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First IFAC Workshop on Fractional Differentiation and Its Application - 19-21 July 2004, Enseirb, Bordeaux, France - FDA'04
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Paper presented at the 5th European Conference Economics and Management of Energy in Industry, Vilamoura, Algarve. Apr. 14-17, 2009, 11p. URL: http:// www.cenertec.pt/ecemei/