957 resultados para model-based reasoning processes


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THE TITLE OF MY THESIS IS THE ROLE OF THE IDEAS AND THEIR CHANGE IN HIGHER EDUCATION POLICY-MAKING PROCESSES FROM THE EIGHTIES TO PRESENT-DAY: THE CASES OF ENGLAND AND NEW ZEALAND IN COMPARATIVE PERSPECTIVE UNDER A THEORETICAL POINT OF VIEW, THE AIM OF MY WORK IS TO CARRY OUT A RESEARCH MODELLED ON THE CONSTRUCTIVIST THEORY. IT FOCUSES ON THE ANALYSIS OF THE IMPACT OF IDEAS ON THE PROCESSES OF POLICY MAKING BY MEANS OF EPISTEMIC COMMUNITIES, THINK TANKS AND VARIOUS SOCIOECONOMIC CONTEXTS THAT MAY HAVE PLAYED A KEY ROLE IN THE CONSTRUCTION OF THE DIFFERENT PATHS. FROM MY POINT OF VIEW IDEAS CONSTITUTE A PRIORITY RESEARCH FIELD WHICH IS WORTH ANALYSING SINCE THEIR ROLE IN POLICY MAKING PROCESSES HAS BEEN TRADITIONALLY RATHER UNEXPLORED. IN THIS CONTEXT AND WITH THE AIM OF DEVELOPING A RESEARCH STRAND BASED ON THE ROLE OF IDEAS, I INTEND TO CARRY ON MY STUDY UNDER THE PERSPECTIVE OF CHANGE. DEPENDING ON THE DATA AND INFORMATION THAT I COLLECTED I EVALUATED THE WEIGHT OF EACH OF THESE VARIABLES AND MAYBE OTHERS SUCH AS THE INSTITUTIONS AND THE INDIVIDUAL INTERESTS, WHICH MAY HAVE INFLUENCED THE FORMATION OF THE POLICY MAKING PROCESSES. UNDER THIS LIGHT, I PLANNED TO ADOPT THE QUALITATIVE METHODOLOGY OF RESEARCH WHICH I BELIEVE TO BE VERY EFFECTIVE AGAINST THE MORE DIFFICULT AND POSSIBLY REDUCTIVE APPLICATION OF QUANTITIVE DATA SETS. I RECKON THEREFORE THAT THE MOST APPROPRIATE TOOLS FOR INFORMATION PROCESSING INCLUDE CONTENT ANALYSIS, AND IN-DEPTH INTERVIEWS TO PERSONALITIES OF THE POLITICAL PANORAMA (ÉLITE OR NOT) WHO HAVE PARTICIPATED IN THE PROCESS OF HIGHER EDUCATION REFORM FROM THE EIGHTIES TO PRESENT-DAY. THE TWO CASES TAKEN INTO CONSIDERATION SURELY SET AN EXAMPLE OF RADICAL REFORM PROCESSES WHICH HAVE OCCURRED IN QUITE DIFFERENT CONTEXTS DETERMINED BY THE SOCIOECONOMIC CHARACTERISTICS AND THE TRAITS OF THE ÉLITE. IN NEW ZEALAND THE DESCRIBED PROCESS HAS TAKEN PLACE WITH A STEADY PACE AND A GOOD GRADE OF CONSEQUANTIALITY, IN LINE WTH THE REFORMS IN OTHER STATE DIVISIONS DRIVEN BY THE IDEAS OF THE NEW PUBLIC MANAGEMENT. CONTRARILY IN ENGLAND THE REFORMATIVE ACTION OF MARGARET THATCHER HAS ACQUIRED A VERY RADICAL CONNOTATION AS IT HAS BROUGHT INTO THE AMBIT OF HIGHER EDUCATION POLICY CONCEPTS LIKE EFFICIENCY, EXCELLENCE, RATIONALIZATION THAT WOULD CONTRAST WITH THE GENERALISTIC AND MASS-ORIENTED IDEAS THAT WERE FASHIONABLE DURING THE SEVENTIES. THE MISSION I INTEND TO ACCOMPLISH THORUGHOUT MY RESEARCH IS TO INVESTIGATE AND ANALYSE INTO MORE DEPTH THE DIFFERENCES THAT SEEM TO EMERGE FROM TWO CONTEXTS WHICH MOST OF THE LITERATURE REGARDS AS A SINGLE MODEL: THE ANGLO-SAXON MODEL. UNDER THIS LIGHT, THE DENSE ANALYSIS OF POLICY PROCESSES ALLOWED TO BRING OUT BOTH THE CONTROVERSIAL AND CONTRASTING ASPECTS OF THE TWO REALITIES COMPARED, AND THE ROLE AND WEIGHT OF VARIABLES SUCH AS IDEAS (MAIN VARIABLE), INSTITUTIONAL SETTINGS AND INDIVIDUAL INTERESTS ACTING IN EACH CONTEXT. THE CASES I MEAN TO ATTEND PRESENT PECULIAR ASPECTS WORTH DEVELOPING AN IN-DEPTH ANALYSIS, AN OUTLINE OF WHICH WILL BE PROVIDED IN THIS ABSTRACT. ENGLAND THE CONSERVATIVE GOVERNMENT, SINCE 1981, INTRODUCED RADICAL CHANGES IN THE SECTOR OF HIGHER EDUCATION: FIRST CUTTING DOWN ON STATE FUNDINGS AND THEN WITH THE CREATION OF AN INSTITUTION FOR THE PLANNING AND LEADERSHIP OF THE POLYTECHNICS (NON-UNIVERSITY SECTOR). AFTERWARDS THE SCHOOL REFORM BY MARGARET THATCHER IN 1988 RAISED TO A GREAT STIR ALL OVER EUROPE DUE TO BOTH ITS CONSIDERABLE INNOVATIVE IMPRINT AND THE STRONG ATTACK AGAINST THE PEDAGOGY OF THE ‘ACTIVE’ SCHOOLING AND PROGRESSIVE EDUCATION, UNTIL THEN RECOGNIZED AS A MERIT OF THE BRITISH PUBLIC SCHOOL. IN THE AMBIT OF UNIVERSITY EDUCATION THIS REFORM, TOGETHER WITH SIMILAR MEASURES BROUGHT IN DURING 1992, PUT INTO PRACTICE THE CONSERVATIVE PRINCIPLES THROUGH A SERIES OF ACTIONS THAT INCLUDED: THE SUPPRESSION OF THE IRREMOVABILITY PRINCIPLE FOR UNIVERSITY TEACHERS; THE INTRODUCTION OF STUDENT LOANS FOR LOW-INCOME STUDENTS AND THE CANCELLATION OF THE CLEAR DISTINCTION BETWEEN UNIVERSITIES AND POLYTECHNICS. THE POLICIES OF THE LABOUR MAJORITY OF MR BLAIR DID NOT QUITE DIVERGE FROM THE CONSERVATIVES’ POSITION. IN 2003 BLAIR’S CABINET RISKED TO BECOME A MINORITY RIGHT ON THE OCCASION OF AN IMPORTANT UNIVERSITY REFORM PROPOSAL. THIS PROPOSAL WOULD FORESEE THE AUTONOMY FOR THE UNIVERSITIES TO RAISE UP TO 3.000 POUNDS THE ENROLMENT FEES FOR STUDENTS (WHILE FORMERLY THE CEILING WAS 1.125 POUNDS). BLAIR HAD TO FACE INTERNAL OPPOSITION WITHIN HIS OWN PARTY IN RELATION TO A MEASURE THAT, ACCORDING TO THE 150 MPS PROMOTERS OF AN ADVERSE MOTION, HAD NOT BEEN INCLUDED IN THE ELECTORAL PROGRAMME AND WOULD RISK CREATING INCOME-BASED DISCRIMINATION AMONG STUDENTS. AS A MATTER OF FACT THE BILL FOCUSED ON THE INTRODUCTION OF VERY LOW-INTEREST STUDENT LOANS TO BE SETTLED ONLY WHEN THE STUDENT WOULD HAVE FOUND A REMUNERATED OCCUPATION (A SYSTEM ALREADY PROVIDED FOR BY THE AUSTRALIAN LEGISLATION). NEW ZEALAND CONTRARILY TO MANY OTHER COUNTRIES, NEW ZEALAND HAS ADOPTED A VERY WIDE VISION OF THE TERTIARY EDUCATION. IT INCLUDES IN FACT THE FULL EDUCATIONAL PROGRAMME THAT IS INTERNATIONALLY RECOGNIZED AS THE POST-SECONDARY EDUCATION. SHOULD WE SPOTLIGHT A PECULIARITY OF THE NEW ZEALAND TERTIARY EDUCATION POLICY THEN IT WOULD BE ‘CHANGE’. LOOKING AT THE REFORM HISTORY RELATED TO THE TERTIARY EDUCATION SYSTEM, WE CAN CLEARLY IDENTIFY FOUR ‘SUB-PERIODS’ FROM THE EIGHTIES TO PRESENT-DAY: 1. BEFORE THE 80S’: AN ELITARIAN SYSTEM CHARACTERIZED BY LOW PARTICIPATION RATES. 2. BETWEEN MID AND LATE 80S’: A TREND TOWARDS THE ENLARGEMENT OF PARTICIPATION ASSOCIATED TO A GREATER COMPETITION. 3. 1990-1999: A FUTHER STEP TOWARDS A COMPETITIVE MODEL BASED ON THE MARKET-ORIENTED SYSTEM. 4. FROM 2000 TO TODAY: A CONTINUOUS EVOLUTION TOWARDS A MORE COMPETITIVE MODEL BASED ON THE MARKET-ORIENTED SYSTEM TOGETHER WITH A GROWING ATTENTION TO STATE CONTROL FOR SOCIAL AND ECONOMIC DEVELOPMENT OF THE NATION. AT PRESENT THE GOVERNMENT OF NEW ZEALAND OPERATES TO STRENGHTHEN THIS PROCESS, PRIMARILY IN RELATION TO THE ROLE OF TERTIARY EDUCATION AS A STEADY FACTOR OF NATIONAL WALFARE, WHERE PROFESSIONAL DEVELOPMENT CONTRIBUTES ACTIVELY TO THE GROWTH OF THE NATIONAL ECONOMIC SYSTEM5. THE CASES OF ENGLAND AND NEW ZEALAND ARE THE FOCUS OF AN IN-DEPTH INVESTIGATION THAT STARTS FROM AN ANALYSIS OF THE POLICIES OF EACH NATION AND DEVELOP INTO A COMPARATIVE STUDY. AT THIS POINT I ATTEMPT TO DRAW SOME PRELIMINARY IMPRESSIONS ON THE FACTS ESSENTIALLY DECRIBED ABOVE. THE UNIVERSITY POLICIES IN ENGLAND AND NEW ZEALAND HAVE BOTH UNDERGONE A SIGNIFICANT REFORMATORY PROCESS SINCE THE EARLY EIGHTIES; IN BOTH CONTEXTS THE IMPORTANCE OF IDEAS THAT CONSTITUTED THE BASE OF POLITICS UNTIL 1980 WAS QUITE RELEVANT. GENERALLY SPEAKING, IN BOTH CASES THE PRE-REFORM POLICIES WERE INSPIRED BY EGALITARIANISM AND EXPANSION OF THE STUDENT POPULATION WHILE THOSE BROUGHT IN BY THE REFORM WOULD PURSUE EFFICIENCY, QUALITY AND COMPETITIVENESS. UNDOUBTEDLY, IN LINE WITH THIS GENERAL TENDENCY THAT REFLECTS THE HYPOTHESIS PROPOSED, THE TWO UNIVERSITY SYSTEMS PRESENT SEVERAL DIFFERENCES. THE UNIVERSITY SYSTEM IN NEW ZEALAND PROCEEDED STEADILY TOWARDS THE IMPLEMENTATION OF A MANAGERIAL CONCEPTION OF TERTIARY EDUCATION, ESPECIALLY FROM 1996 ONWARDS, IN ACCORDANCE WITH THE REFORMATORY PROCESS OF THE WHOLE PUBLIC SECTOR. IN THE UNITED KINGDOM, AS IN THE REST OF EUROPE, THE NEW APPROACH TO UNIVERSITY POLICY-MAKING HAD TO CONFRONT A DEEP-ROOTED TRADITION OF PROGRESSIVE EDUCATION AND THE IDEA OF EDUCATION EXPANSION THAT IN FACT DOMINATED UNTIL THE EIGHTIES. FROM THIS VIEW POINT THE GOVERNING ACTION OF MARGARET THATCHER GAVE RISE TO A RADICAL CHANGE THAT REVOLUTIONIZED THE OBJECTIVES AND KEY VALUES OF THE WHOLE EDUCATIONAL SYSTEM, IN PARTICULAR IN THE HIGHER EDUCATION SECTOR. IDEAS AS EFFICIENCY, EXCELLENCE AND CONTROL OF THE PERFORMANCE BECAME DECISIVE. THE LABOUR CABINETS OF BLAIR DEVELOPED IN THE WAKE OF CONSERVATIVE REFORMS. THIS APPEARS TO BE A FOCAL POINT OF THIS STUDY THAT OBSERVES HOW ALSO IN NEW ZEALAND THE REFORMING PROCESS OCCURRED TRANSVERSELY DURING PROGRESSIVE AND CONSERVATIVE ADMINISTRATIONS. THE PRELIMINARY IMPRESSION IS THEREFORE THAT IDEAS DEEPLY MARK THE REFORMATIVE PROCESSES: THE AIM OF MY RESEARCH IS TO VERIFY TO WHICH EXTENT THIS STATEMENT IS TRUE. IN ORDER TO BUILD A COMPREHENSIVE ANALYLIS, FURTHER SIGNIFICANT FACTORS WILL HAVE TO BE INVESTIGATED: THE WAY IDEAS ARE PERCEIVED AND IMPLEMENTED BY THE DIFFERENT POLITICAL ELITES; HOW THE VARIOUS SOCIOECONOMIC CONTEXTS INFLUENCE THE REFORMATIVE PROCESS; HOW THE INSTITUTIONAL STRUCTURES CONDITION THE POLICY-MAKING PROCESSES; WHETHER INDIVIDUAL INTERESTS PLAY A ROLE AND, IF YES, TO WHICH EXTENT.

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Membrane-based separation processes are acquiring, in the last years, an increasing importance because of their intrinsic energetic and environmental sustainability: some types of polymeric materials, showing adequate perm-selectivity features, appear rather suitable for these applications, because of their relatively low cost and easy processability. In this work have been studied two different types of polymeric membranes, in view of possible applications to the gas separation processes, i.e. Mixed Matrix Membranes (MMMs) and high free volume glassy polymers. Since the early 90’s, it has been understood that the performances of polymeric materials in the field of gas separations show an upper bound in terms of permeability and selectivity: in particular, an increase of permeability is often accompanied by a decrease of selectivity and vice-versa, while several inorganic materials, like zeolites or silica derivates, can overcome this limitation. As a consequence, it has been developed the idea of dispersing inorganic particles in polymeric matrices, in order to obtain membranes with improved perm-selectivity features. In particular, dispersing fumed silica nanoparticles in high free volume glassy polymers improves in all the cases gases and vapours permeability, while the selectivity may either increase or decrease, depending upon material and gas mixture: that effect is due to the capacity of nanoparticles to disrupt the local chain packing, increasing the dimensions of excess free volume elements trapped in the polymer matrix. In this work different kinds of MMMs were fabricated using amorphous Teflon® AF or PTMSP and fumed silica: in all the cases, a considerable increase of solubility, diffusivity and permeability of gases and vapours (n-alkanes, CO2, methanol) was observed, while the selectivity shows a non-monotonous trend with filler fraction. Moreover, the classical models for composites are not able to capture the increase of transport properties due to the silica addition, so it has been necessary to develop and validate an appropriate thermodynamic model that allows to predict correctly the mass transport features of MMMs. In this work, another material, called poly-trimethylsilyl-norbornene (PTMSN) was examined: it is a new generation high free volume glassy polymer that, like PTMSP, shows unusual high permeability and selectivity levels to the more condensable vapours. These two polymer differ each other because PTMSN shows a more pronounced chemical stability, due to its structure double-bond free. For this polymer, a set of Lattice Fluid parameters was estimated, making possible a comparison between experimental and theoretical solubility isotherms for hydrocarbons and alcoholic vapours: the successfully modelling task, based on application of NELF model, offers a reliable alternative to direct sorption measurement, which is extremely time-consuming due to the relevant relaxation phenomena showed by each sorption step. For this material also dilation experiments were performed, in order to quantify its dimensional stability in presence of large size, swelling vapours.

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Forecasting the time, location, nature, and scale of volcanic eruptions is one of the most urgent aspects of modern applied volcanology. The reliability of probabilistic forecasting procedures is strongly related to the reliability of the input information provided, implying objective criteria for interpreting the historical and monitoring data. For this reason both, detailed analysis of past data and more basic research into the processes of volcanism, are fundamental tasks of a continuous information-gain process; in this way the precursor events of eruptions can be better interpreted in terms of their physical meanings with correlated uncertainties. This should lead to better predictions of the nature of eruptive events. In this work we have studied different problems associated with the long- and short-term eruption forecasting assessment. First, we discuss different approaches for the analysis of the eruptive history of a volcano, most of them generally applied for long-term eruption forecasting purposes; furthermore, we present a model based on the characteristics of a Brownian passage-time process to describe recurrent eruptive activity, and apply it for long-term, time-dependent, eruption forecasting (Chapter 1). Conversely, in an effort to define further monitoring parameters as input data for short-term eruption forecasting in probabilistic models (as for example, the Bayesian Event Tree for eruption forecasting -BET_EF-), we analyze some characteristics of typical seismic activity recorded in active volcanoes; in particular, we use some methodologies that may be applied to analyze long-period (LP) events (Chapter 2) and volcano-tectonic (VT) seismic swarms (Chapter 3); our analysis in general are oriented toward the tracking of phenomena that can provide information about magmatic processes. Finally, we discuss some possible ways to integrate the results presented in Chapters 1 (for long-term EF), 2 and 3 (for short-term EF) in the BET_EF model (Chapter 4).

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Two of the main features of today complex software systems like pervasive computing systems and Internet-based applications are distribution and openness. Distribution revolves around three orthogonal dimensions: (i) distribution of control|systems are characterised by several independent computational entities and devices, each representing an autonomous and proactive locus of control; (ii) spatial distribution|entities and devices are physically distributed and connected in a global (such as the Internet) or local network; and (iii) temporal distribution|interacting system components come and go over time, and are not required to be available for interaction at the same time. Openness deals with the heterogeneity and dynamism of system components: complex computational systems are open to the integration of diverse components, heterogeneous in terms of architecture and technology, and are dynamic since they allow components to be updated, added, or removed while the system is running. The engineering of open and distributed computational systems mandates for the adoption of a software infrastructure whose underlying model and technology could provide the required level of uncoupling among system components. This is the main motivation behind current research trends in the area of coordination middleware to exploit tuple-based coordination models in the engineering of complex software systems, since they intrinsically provide coordinated components with communication uncoupling and further details in the references therein. An additional daunting challenge for tuple-based models comes from knowledge-intensive application scenarios, namely, scenarios where most of the activities are based on knowledge in some form|and where knowledge becomes the prominent means by which systems get coordinated. Handling knowledge in tuple-based systems induces problems in terms of syntax - e.g., two tuples containing the same data may not match due to differences in the tuple structure - and (mostly) of semantics|e.g., two tuples representing the same information may not match based on a dierent syntax adopted. Till now, the problem has been faced by exploiting tuple-based coordination within a middleware for knowledge intensive environments: e.g., experiments with tuple-based coordination within a Semantic Web middleware (surveys analogous approaches). However, they appear to be designed to tackle the design of coordination for specic application contexts like Semantic Web and Semantic Web Services, and they result in a rather involved extension of the tuple space model. The main goal of this thesis was to conceive a more general approach to semantic coordination. In particular, it was developed the model and technology of semantic tuple centres. It is adopted the tuple centre model as main coordination abstraction to manage system interactions. A tuple centre can be seen as a programmable tuple space, i.e. an extension of a Linda tuple space, where the behaviour of the tuple space can be programmed so as to react to interaction events. By encapsulating coordination laws within coordination media, tuple centres promote coordination uncoupling among coordinated components. Then, the tuple centre model was semantically enriched: a main design choice in this work was to try not to completely redesign the existing syntactic tuple space model, but rather provide a smooth extension that { although supporting semantic reasoning { keep the simplicity of tuple and tuple matching as easier as possible. By encapsulating the semantic representation of the domain of discourse within coordination media, semantic tuple centres promote semantic uncoupling among coordinated components. The main contributions of the thesis are: (i) the design of the semantic tuple centre model; (ii) the implementation and evaluation of the model based on an existent coordination infrastructure; (iii) a view of the application scenarios in which semantic tuple centres seem to be suitable as coordination media.

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The diagnosis, grading and classification of tumours has benefited considerably from the development of DCE-MRI which is now essential to the adequate clinical management of many tumour types due to its capability in detecting active angiogenesis. Several strategies have been proposed for DCE-MRI evaluation. Visual inspection of contrast agent concentration curves vs time is a very simple yet operator dependent procedure, therefore more objective approaches have been developed in order to facilitate comparison between studies. In so called model free approaches, descriptive or heuristic information extracted from time series raw data have been used for tissue classification. The main issue concerning these schemes is that they have not a direct interpretation in terms of physiological properties of the tissues. On the other hand, model based investigations typically involve compartmental tracer kinetic modelling and pixel-by-pixel estimation of kinetic parameters via non-linear regression applied on region of interests opportunely selected by the physician. This approach has the advantage to provide parameters directly related to the pathophysiological properties of the tissue such as vessel permeability, local regional blood flow, extraction fraction, concentration gradient between plasma and extravascular-extracellular space. Anyway, nonlinear modelling is computational demanding and the accuracy of the estimates can be affected by the signal-to-noise ratio and by the initial solutions. The principal aim of this thesis is investigate the use of semi-quantitative and quantitative parameters for segmentation and classification of breast lesion. The objectives can be subdivided as follow: describe the principal techniques to evaluate time intensity curve in DCE-MRI with focus on kinetic model proposed in literature; to evaluate the influence in parametrization choice for a classic bi-compartmental kinetic models; to evaluate the performance of a method for simultaneous tracer kinetic modelling and pixel classification; to evaluate performance of machine learning techniques training for segmentation and classification of breast lesion.

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Particulate matter is one of the main atmospheric pollutants, with a great chemical-environmental relevance. Improving knowledge of the sources of particulate matter and of their apportionment is needed to handle and fulfill the legislation regarding this pollutant, to support further development of air policy as well as air pollution management. Various instruments have been used to understand the sources of particulate matter and atmospheric radiotracers at the site of Mt. Cimone (44.18° N, 10.7° E, 2165 m asl), hosting a global WMO-GAW station. Thanks to its characteristics, this location is suitable investigate the regional and long-range transport of polluted air masses on the background Southern-Europe free-troposphere. In particular, PM10 data sampled at the station in the period 1998-2011 were analyzed in the framework of the main meteorological and territorial features. A receptor model based on back trajectories was applied to study the source regions of particulate matter. Simultaneous measurements of atmospheric radionuclides Pb-210 and Be-7 acquired together with PM10 have also been analysed to acquire a better understanding of vertical and horizontal transports able to affect atmospheric composition. Seasonal variations of atmospheric radiotracers have been studied both analysing the long-term time series acquired at the measurement site as well as by means of a state-of-the-art global 3-D chemistry and transport model. Advection patterns characterizing the circulation at the site have been identified by means of clusters of back-trajectories. Finally, the results of a source apportionment study of particulate matter carried on in a midsize town of the Po Valley (actually recognised as one of the most polluted European regions) are reported. An approach exploiting different techniques, and in particular different kinds of models, successfully achieved a characterization of the processes/sources of particulate matter at the two sites, and of atmospheric radiotracers at the site of Mt. Cimone.

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Polymeric membranes represent a promising technology for gas separation processes, thanks to low costs, reduced energy consumption and limited waste production. The present thesis aims at studying the transport properties of two membrane materials, suitable for CO2 purification applications. In the first part, a polyimide, Matrimid 5218, has been throughout investigated, with particular reference to the effect of thermal treatment, aging and the presence of water vapor in the gas transport process. Permeability measurements showed that thermal history affects relevantly the diffusion of gas molecules across the membrane, influencing also the stability of the separation performances. Subsequently, the effect of water on Matrimid transport properties has been characterized for a wide set of incondensable penetrants. A monotonous reduction of permeability took place at increasing the water concentration within the polymer matrix, affecting the investigated gaseous species to the same extent, despite the different thermodynamic and kinetic features. In this view, a novel empirical model, based on the Free Volume Theory, has been proposed to qualitatively describe the phenomenon. Moreover, according to the accurate representation of the experimental data, the suggested approach has been combined with a more rigorous thermodynamic tool (NELF Model), allowing an exhaustive description of water influence on the single parameters contributing to the gas permeation across the membrane. In the second part, the study has focused on the synthesis and characterization of facilitated transport membranes, able to achieving outstanding separation performances thanks to the chemical enhancement of CO2 permeability. In particular, the transport properties have been investigated for high pressure CO2 separation applications and specific solutions have been proposed to solve stability issues, frequently arising under such severe conditions. Finally, the effect of different process parameters have been investigated, aiming at the identification of the optimal conditions capable to maximize the separation performance.

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In this work I discuss several key aspects of welfare economics and policy analysis and I propose two original contributions to the growing field of behavioral public policymaking. After providing a historical perspective of welfare economics and an overview of policy analysis processes in the introductory chapter, in chapter 2 I discuss a debated issue of policymaking, the choice of the social welfare function. I contribute to this debate by proposing an original methodological contribution based on the analysis of the quantitative relationship among different social welfare functional forms commonly used by policy analysts. In chapter 3 I then discuss a behavioral policy to contrast indirect tax evasion based on the use of lotteries. I show that the predictions of my model based on non-expected utility are consistent with observed, and so far unexplained, empirical evidence of the policy success. Finally, in chapter 4 I investigate by mean of a laboratory experiment the effects of social influence on the individual likelihood to engage in altruistic punishment. I show that bystanders’ decision to engage in punishment is influenced by the punishment behavior of their peers and I suggest ways to enact behavioral policies that exploit this finding.

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This work is focused on the analysis of sea–level change (last century), based mainly on instrumental observations. During this period, individual components of sea–level change are investigated, both at global and regional scales. Some of the geophysical processes responsible for current sea-level change such as glacial isostatic adjustments and current melting terrestrial ice sources, have been modeled and compared with observations. A new value of global mean sea level change based of tide gauges observations has been independently assessed in 1.5 mm/year, using corrections for glacial isostatic adjustment obtained with different models as a criterion for the tide gauge selection. The long wavelength spatial variability of the main components of sea–level change has been investigated by means of traditional and new spectral methods. Complex non–linear trends and abrupt sea–level variations shown by tide gauges records have been addressed applying different approaches to regional case studies. The Ensemble Empirical Mode Decomposition technique has been used to analyse tide gauges records from the Adriatic Sea to ascertain the existence of cyclic sea-level variations. An Early Warning approach have been adopted to detect tipping points in sea–level records of North East Pacific and their relationship with oceanic modes. Global sea–level projections to year 2100 have been obtained by a semi-empirical approach based on the artificial neural network method. In addition, a model-based approach has been applied to the case of the Mediterranean Sea, obtaining sea-level projection to year 2050.

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Decision trees have been proposed as a basis for modifying table based injection to reduce transient particulate spikes during the turbocharger lag period. It has been shown that decision trees can detect particulate spikes in real time. In well calibrated electronically controlled diesel engines these spikes are narrow and are encompassed by a wider NOx spike. Decision trees have been shown to pinpoint the exact location of measured opacity spikes in real time thus enabling targeted PM reduction with near zero NOx penalty. A calibrated dimensional model has been used to demonstrate the possible reduction of particulate matter with targeted injection pressure pulses. Post injection strategy optimized for near stoichiometric combustion has been shown to provide additional benefits. Empirical models have been used to calculate emission tradeoffs over the entire FTP cycle. An empirical model based transient calibration has been used to demonstrate that such targeted transient modifiers are more beneficial at lower engine-out NOx levels.

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Indoor radon is regularly measured in Switzerland. However, a nationwide model to predict residential radon levels has not been developed. The aim of this study was to develop a prediction model to assess indoor radon concentrations in Switzerland. The model was based on 44,631 measurements from the nationwide Swiss radon database collected between 1994 and 2004. Of these, 80% randomly selected measurements were used for model development and the remaining 20% for an independent model validation. A multivariable log-linear regression model was fitted and relevant predictors selected according to evidence from the literature, the adjusted R², the Akaike's information criterion (AIC), and the Bayesian information criterion (BIC). The prediction model was evaluated by calculating Spearman rank correlation between measured and predicted values. Additionally, the predicted values were categorised into three categories (50th, 50th-90th and 90th percentile) and compared with measured categories using a weighted Kappa statistic. The most relevant predictors for indoor radon levels were tectonic units and year of construction of the building, followed by soil texture, degree of urbanisation, floor of the building where the measurement was taken and housing type (P-values <0.001 for all). Mean predicted radon values (geometric mean) were 66 Bq/m³ (interquartile range 40-111 Bq/m³) in the lowest exposure category, 126 Bq/m³ (69-215 Bq/m³) in the medium category, and 219 Bq/m³ (108-427 Bq/m³) in the highest category. Spearman correlation between predictions and measurements was 0.45 (95%-CI: 0.44; 0.46) for the development dataset and 0.44 (95%-CI: 0.42; 0.46) for the validation dataset. Kappa coefficients were 0.31 for the development and 0.30 for the validation dataset, respectively. The model explained 20% overall variability (adjusted R²). In conclusion, this residential radon prediction model, based on a large number of measurements, was demonstrated to be robust through validation with an independent dataset. The model is appropriate for predicting radon level exposure of the Swiss population in epidemiological research. Nevertheless, some exposure misclassification and regression to the mean is unavoidable and should be taken into account in future applications of the model.

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Model-based calibration of steady-state engine operation is commonly performed with highly parameterized empirical models that are accurate but not very robust, particularly when predicting highly nonlinear responses such as diesel smoke emissions. To address this problem, and to boost the accuracy of more robust non-parametric methods to the same level, GT-Power was used to transform the empirical model input space into multiple input spaces that simplified the input-output relationship and improved the accuracy and robustness of smoke predictions made by three commonly used empirical modeling methods: Multivariate Regression, Neural Networks and the k-Nearest Neighbor method. The availability of multiple input spaces allowed the development of two committee techniques: a 'Simple Committee' technique that used averaged predictions from a set of 10 pre-selected input spaces chosen by the training data and the "Minimum Variance Committee" technique where the input spaces for each prediction were chosen on the basis of disagreement between the three modeling methods. This latter technique equalized the performance of the three modeling methods. The successively increasing improvements resulting from the use of a single best transformed input space (Best Combination Technique), Simple Committee Technique and Minimum Variance Committee Technique were verified with hypothesis testing. The transformed input spaces were also shown to improve outlier detection and to improve k-Nearest Neighbor performance when predicting dynamic emissions with steady-state training data. An unexpected finding was that the benefits of input space transformation were unaffected by changes in the hardware or the calibration of the underlying GT-Power model.

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The quantification of the structural properties of snow is traditionally based on model-based stereology. Model-based stereology requires assumptions about the shape of the investigated structure. Here, we show how the density, specific surface area, and grain boundary area can be measured using a design-based method, where no assumptions about structural properties are necessary. The stereological results were also compared to X-ray tomography to control the accuracy of the method. The specific surface area calculated with the stereological method was 19.8 ± 12.3% smaller than with X-ray tomography. For the density, the stereological method gave results that were 11.7 ± 12.1% larger than X-ray tomography. The statistical analysis of the estimates confirmed that the stereological method and the sampling used are accurate. This stereological method was successfully tested on artificially produced ice beads but also on several snow types. Combining stereology and polarisation microscopy provides a good estimate of grain boundary areas in ice beads and in natural snow, with some limitatio

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Chironomids preserved in a sediment core from Lago di Origlio (416 m a.s.l.), a lake in the foreland of the Southern Swiss Alps, allowed quantitative reconstruction of Late Glacial and Early Holocene summer temperatures using a combined Swiss–Norwegian temperature inference model based on chironomid assemblages from 274 lakes. We reconstruct July air temperatures of ca. 10 °C between 17 300 and 16 000 cal yr BP, a rather abrupt warming to ca. 12.0 °C at ca. 16 500–16 000 cal yr BP, and a strong temperature increase at the transition to the Bølling/Allerød interstadial with average temperatures of about 14 °C. During the Younger Dryas and earliest Holocene similar temperatures are reconstructed as for the interstadial. The rather abrupt warming at 16 500–16 000 cal yr BP is consistent with sea-surface temperature as well as speleothem records, which indicate a warming after the end of Heinrich event 1 (sensu stricto) and before the Bølling/Allerød interstadial in southern Europe and the Mediterranean Sea. Pollen records from Origlio and other sites in southern Switzerland and northern Italy indicate an early reforestation of the lowlands 2000–1500 yr prior to the large-scale afforestation of Central Europe at the onset of the Bølling/Allerød period at ca. 14 700–14 600 cal yr BP. Our results suggest that these early afforestation processes in the formerly glaciated areas of northern Italy and southern Switzerland have been promoted by increasing temperatures.

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Professor Sir David R. Cox (DRC) is widely acknowledged as among the most important scientists of the second half of the twentieth century. He inherited the mantle of statistical science from Pearson and Fisher, advanced their ideas, and translated statistical theory into practice so as to forever change the application of statistics in many fields, but especially biology and medicine. The logistic and proportional hazards models he substantially developed, are arguably among the most influential biostatistical methods in current practice. This paper looks forward over the period from DRC's 80th to 90th birthdays, to speculate about the future of biostatistics, drawing lessons from DRC's contributions along the way. We consider "Cox's model" of biostatistics, an approach to statistical science that: formulates scientific questions or quantities in terms of parameters gamma in probability models f(y; gamma) that represent in a parsimonious fashion, the underlying scientific mechanisms (Cox, 1997); partition the parameters gamma = theta, eta into a subset of interest theta and other "nuisance parameters" eta necessary to complete the probability distribution (Cox and Hinkley, 1974); develops methods of inference about the scientific quantities that depend as little as possible upon the nuisance parameters (Barndorff-Nielsen and Cox, 1989); and thinks critically about the appropriate conditional distribution on which to base infrences. We briefly review exciting biomedical and public health challenges that are capable of driving statistical developments in the next decade. We discuss the statistical models and model-based inferences central to the CM approach, contrasting them with computationally-intensive strategies for prediction and inference advocated by Breiman and others (e.g. Breiman, 2001) and to more traditional design-based methods of inference (Fisher, 1935). We discuss the hierarchical (multi-level) model as an example of the future challanges and opportunities for model-based inference. We then consider the role of conditional inference, a second key element of the CM. Recent examples from genetics are used to illustrate these ideas. Finally, the paper examines causal inference and statistical computing, two other topics we believe will be central to biostatistics research and practice in the coming decade. Throughout the paper, we attempt to indicate how DRC's work and the "Cox Model" have set a standard of excellence to which all can aspire in the future.