885 resultados para Methods for Multi-criteria Evaluation
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Objective. Evidence exists for an association between migraine and ischaemic stroke, but there is uncertainty about whether migraine is a risk factor for subarachnoid haemorrhage (SAH). Methods. A multi-centre, population-based, case-control study using cases of first-ever SAH during 1995-98 and matched controls in four study centres in Australia and New Zealand. Self- or proxy-reported history, frequency and characteristics of headaches, classified according to 1988 International Headache Society diagnostic criteria. Results. 206 of 432 (48%) cases and 236 of 473 (50%) controls had a history of headaches. The frequency and characteristics of headaches were similar between the two groups. No association was found in logistic regression analyses for history or frequency of headaches, or migraine headaches. Conclusions. No evidence was found for an association between recurrent headaches and SAH. Such information is important for counselling patients and families about the significance of past and ongoing headaches in relation to this illness. (c) 2005 Elsevier Ltd. All rights reserved.
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Whilst traditional optimisation techniques based on mathematical programming techniques are in common use, they suffer from their inability to explore the complexity of decision problems addressed using agricultural system models. In these models, the full decision space is usually very large while the solution space is characterized by many local optima. Methods to search such large decision spaces rely on effective sampling of the problem domain. Nevertheless, problem reduction based on insight into agronomic relations and farming practice is necessary to safeguard computational feasibility. Here, we present a global search approach based on an Evolutionary Algorithm (EA). We introduce a multi-objective evaluation technique within this EA framework, linking the optimisation procedure to the APSIM cropping systems model. The approach addresses the issue of system management when faced with a trade-off between economic and ecological consequences.
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Third-party logistics service providers (3PLs) play a vital role in contemporary supply chain management. Evaluation and selection of the right 3PLs depends on a wide range of quantitative and qualitative criteria rather than cost-based factors. Although various multi-criteria decision making approaches have been proposed, they have not considered the impact of business objectives and requirements of company stakeholders on the evaluating criteria. To enable the "voice" of company stakeholders is considered, this paper develops an integrated approach for selecting 3PL strategically. In the approach, multiple evaluating criteria are derived from the requirements of company stakeholders using a series of house of quality (HOQ). The importance of evaluating criteria is prioritized with respect to the degree of achieving the stakeholder requirements using analytic hierarchy process (AHP). Based on the ranked criteria, alternative 3PLs are evaluated and compared with each other using AHP again to make an optimal selection.
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Coherent optical orthogonal frequency division multiplexing (CO-OFDM) is an attractive transmission technique to virtually eliminate intersymbol interference caused by chromatic dispersion and polarization-mode dispersion. Design, development, and operation of CO-OFDM systems require simple, efficient, and reliable methods of their performance evaluation. In this paper, we demonstrate an accurate bit error rate estimation method for QPSK CO-OFDM transmission based on the probability density function of the received QPSK symbols. By comparing with other known approaches, including data-aided and nondata-aided error vector magnitude, we show that the proposed method offers the most accurate estimate of the system performance for both single channel and wavelength division multiplexing QPSK CO-OFDM transmission systems. 2014 IEEE.
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2000 Math. Subject Classification: 33E12, 65D20, 33F05, 30E15
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This paper presents a survey of the existing services provided by the digital libraries and repositories on mathematics of the content provider partners in the EuDML project. The purpose is to support the development of the concepts, criteria and methods for the continuous evaluation of these and new relevant existing services. The work was concentrated on the classification of the relevant services in order to specify a common evaluating structure.
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Egyes alternatvk, forgatknyvek, technolgik stb. fenntarthatsgnak rtkelse definciszeren tbbdimenzis problma. A megfelel alternatva kivlasztsnl ugyanis a dntshozknak egyszerre kell figyelembe vennik krnyezetvdelmi, gazdasgi s trsadalmi szempontokat. Az ilyen dntseket tmogathatjk tbbszempont dntshozatali modellek. A tanulmny ht tbbszempont dntsi mdszertan (MAU, AHP, ELECTRE, PROMETHEE, REGIME, NAIADE s idelis-referencia pont) alkalmazhatsgt vizsglja rszvteli krlmnyek kztt. Az utbbi vek e tmban publiklt esettanulmnyait ttekintve megllapthat, hogy egyik mdszer sem dominlja a tbbit, azok klnbz felttelek mellett eltr sikerrel hasznlhatk. Ennek ellenre a klnbz technikk kombincijval elllthatunk olyan eljrsokat, melyekkel az egyes mdszerek elnyeit mg jobban kiaknzhatjuk. ________ Measuring and comparing the sustainability of certain actions, scenarios, technologies, etc. by definition is a multidimensional problem. Decision makers must consider environmental, economic and social aspects when choosing an alternative course of action. Such decisions can be aided by multi-criteria decision analysis (MCDA). In this paper participatory seven different MCDA methodologies are investigated (MAU, the Analytic Hierarchic Process (AHP), the ELECTRE, PROMETHEE, REGIME, and NAIADE methods and the Ideal and reference point approaches). It is based on a series of reports, in which more than 30 real world case studies focusing on participatory MCDA were reviewed. It is emphasized that there is no best choice from the list of MCDA techniques, but some methods fit certain decision problems more than others. However, with the combination of these methodologies some complementary benefits of the different techniques can be exploited.
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We investigated controls on the water chemistry of a South Ecuadorian cloud forest catchment which is partly pristine, and partly converted to extensive pasture. From April 2007 to May 2008 water samples were taken weekly to biweekly at nine different subcatchments, and were screened for differences in electric conductivity, pH, anion, as well as element composition. A principal component analysis was conducted to reduce dimensionality of the data set and define major factors explaining variation in the data. Three main factors were isolated by a subset of 10 elements (Ca2+, Ce, Gd, K+, Mg2+, Na+, Nd, Rb, Sr, Y), explaining around 90% of the data variation. Land-use was the major factor controlling and changing water chemistry of the subcatchments. A second factor was associated with the concentration of rare earth elements in water, presumably highlighting other anthropogenic influences such as gravel excavation or road construction. Around 12% of the variation was explained by the third component, which was defined by the occurrence of Rb and K and represents the influence of vegetation dynamics on element accumulation and wash-out. Comparison of base- and fast flow concentrations led to the assumption that a significant portion of soil water from around 30 cm depth contributes to storm flow, as revealed by increased rare earth element concentrations in fast flow samples. Our findings demonstrate the utility of multi-tracer principal component analysis to study tropical headwater streams, and emphasize the need for effective land management in cloud forest catchments.
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This thesis presents quantitative studies of T cell and dendritic cell (DC) behaviour in mouse lymph nodes (LNs) in the naive state and following immunisation. These processes are of importance and interest in basic immunology, and better understanding could improve both diagnostic capacity and therapeutic manipulations, potentially helping in producing more effective vaccines or developing treatments for autoimmune diseases. The problem is also interesting conceptually as it is relevant to other fields where 3D movement of objects is tracked with a discrete scanning interval. A general immunology introduction is presented in chapter 1. In chapter 2, I apply quantitative methods to multi-photon imaging data to measure how T cells and DCs are spatially arranged in LNs. This has been previously studied to describe differences between the naive and immunised state and as an indicator of the magnitude of the immune response in LNs, but previous analyses have been generally descriptive. The quantitative analysis shows that some of the previous conclusions may have been premature. In chapter 3, I use Bayesian state-space models to test some hypotheses about the mode of T cell search for DCs. A two-state mode of movement where T cells can be classified as either interacting to a DC or freely migrating is supported over a model where T cells would home in on DCs at distance through for example the action of chemokines. In chapter 4, I study whether T cell migration is linked to the geometric structure of the fibroblast reticular network (FRC). I find support for the hypothesis that the movement is constrained to the fibroblast reticular cell (FRC) network over an alternative 'random walk with persistence time' model where cells would move randomly, with a short-term persistence driven by a hypothetical T cell intrinsic 'clock'. I also present unexpected results on the FRC network geometry. Finally, a quantitative method is presented for addressing some measurement biases inherent to multi-photon imaging. In all three chapters, novel findings are made, and the methods developed have the potential for further use to address important problems in the field. In chapter 5, I present a summary and synthesis of results from chapters 3-4 and a more speculative discussion of these results and potential future directions.
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Resumen La Evaluacin Mlticriterio (EMC), integra las diferentes dimensiones de una realidad en un slo marco de anlisis, para brindar un acercamiento de la gestin del recurso hdrico en los cantones Barva, Santa Brbara y San Rafael de Heredia, con el objetivo de generar las polticas hdricas locales adecuadas. Esta estructura metodolgica presenta una gran transparencia como herramienta en la toma de decisiones, identificando claramente los diferentes actores involucrados, describiendo, al mismo tiempo los problemas de gestin del recurso hdrico en la zona; a la vez que permite delimitar los conflictos sociales y mostrar diferentes posibilidades para su solucin a travs de compromisos y dilogo entre las partes. De ste dilogo emergen soluciones concretas, estructuradas como polticas locales hdricas, tales como: Planes de Gestin Hdrica, Inversin Pblica y Privada, Coordinacin Institucional, Reforma Institucional/legal. La zona presenta una atmsfera conflictiva alrededor de la gestin del agua y por tanto en la estructuracin de polticas hdricas locales. Esta conflictividad sectorial(es decir por cantn) se superpone a una extraordinaria conflictividad territorial. La escasez o competencia sobre el agua se fundamenta en unas demandas crecientes que son expresin de un proceso de desarrollo urbano y turstico acelerado y desordenado. Abstract The Evaluation Multi-criteria analysis (EMA), integrates the different dimensions of a reality in an analysis mark, to offer an approach of the administration of the hydric resources in the Heredias cities of Barva, Santa Brbara and San Rafael, with the objective of generating the local adequate hydrics policies. This methodological structure presents a great transparency like tool in the taking of decisions, identifying the different involved actors clearly, describing, at the same time, the problems of administration of the hydric resources in the area; and at the same time, it allows to define the social conflicts, as showing different possibilities for their solution through commitments and dialogue among the parts. Of this dialogue concrete solutions they emerge, structured as hydrics local policies, such as: Plans of hydric management, Public and Private Investment, Institutional Coordination, Institucional/legal reforms. The area presents a conflicting atmosphere around the administration of the water and therefore in the structuring of local hydrics policies. This conflict 'sectorial' (to say for canton) it is superimposed to an extraordinary 'territorial' conflict. The shortage or competition for water are based in some growing demands that are expression of a process of quick and disordered urban and tourist development.
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The study of Quality of Life (Qol) has been conducted on various scales throughout the years with focus on assessing overall quality of living amongst citizens. The main focus in these studies have been on economic factors, with the purpose of creating a Quality of Life Index (QLI).When it comes down to narrowing the focus to the environment and factors like Urban Green Spaces (UGS) and air quality the topic gets more focused on pointing out how each alternative meets this certain criteria. With the benefits of UGS and a healthy environment in focus a new Environmental Quality of Life Index (EQLI) will be proposed by incorporating Multi Criteria Analysis (MCA) and Geographical Information Systems (GIS). Working with MCA on complex environmental problems and incorporating it with GIS is a challenging but rewarding task, and has proven to be an efficient approach among environmental scientists. Background information on three MCA methods will be shown: Analytical Hierarchy Process (AHP), Regime Analysis and PROMETHEE. A survey based on a previous study conducted on the status of UGS within European cities was sent to 18 municipalities in the study area. The survey consists of evaluating the current status of UGS as well as planning and management of UGS with in municipalities for the purpose of getting criteria material for the selected MCA method. The current situation of UGS is assessed with use of GIS software and change detection is done on a 10 year period using NDVI index for comparison purposes to one of the criteria in the MCA. To add to the criteria, interpolation of nitrogen dioxide levels was performed with ordinary kriging and the results transformed into indicator values. The final outcome is an EQLI map with indicators of environmentally attractive municipalities with ranking based on predefinedMCA criteria using PROMETHEE I pairwise comparison and PROMETHEE II complete ranking of alternatives. The proposed methodology is applied to Lisbons Metropolitan Area, Portugal.
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Mestrado em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia - UL
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Tese (doutorado)Universidade de Braslia, Faculdade de Tecnologia, Departamento de Engenharia Civil e Ambiental, 2016.
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Antecedentes y objetivos: La hiperhidrosis primaria afecta el 2,8% de la poblacin de Estados Unidos. Condicin que impacta el desarrollo social de los individuos afectados, ocasionando fobia social. Existen opciones disponibles para el tratamiento de la hiperhidrosis incluyendo medicamentos tpico, sistmico, inyectable y quirrgico. El objetivo de sta revisin sistemtica de la literatura es determinar la efectividad y seguridad de los dispositivos de emisin de microondas, radiofrecuencia no ablativa y sistema de ultrasonido microfocalizado para el tratamiento de la hiperhidrosis primaria. Materiales y mtodos: Se realiz una revisin sistemtica de la literatura de artculos obtenidos de bases de datos: Medline, Cochrane, Embase, Ovid y Scielo. Se incluyeron ensayos clnicos aleatorizados controlados, ensayos cuasiexperimentales desde el 2011; donde evaluaran el uso de estos dispositivos en el manejo de hiperhidrosis primaria. Resultados: Se seleccionaron 21 artculos en total. Se encontr que con los tres dispositivos se logra una reduccin significativa a puntajes entre 1 y 2 de la escala de Severidad de la Hiperhidrosis; en 3 estudios se encontr mejora en la calidad de vida; los eventos adversos fueron transitorios, siendo ms frecuentes con el dispositivo de emisin de microondas. Conclusin: Primera revisin sistemtica de la literatura sobre el efecto de estos tres dispositivos en el manejo de hiperhidrosis. Se espera aportar a la literatura existente una recomendacin acerca de la efectividad y seguridad de estos dispositivos para que sea aplicado en los pacientes con diagnstico de hiperhidrosis primaria.
