Dissertationen zum Thema „Age of uncertainty“

This thesis investigates the problematic of social and political complexity. It attempts to answer the question of how power operates in a world of complex and globalised social, political, and economic systems. The basic claims of the thesis are as follows. Firstly, we can find the tools to understand social complexity in complexity theory. In turn, the conceptual innovations of complexity theory can be deployed to rethink the pre-existing political theoretical tradition of hegemony. We argue that the most significant existing theories of hegemony have been produced in relation to moments of increasing real world social complexity, and that there exists an under-developed seam of thinking already within the tradition which evokes key concepts from complexity theory. Therefore, the flaws in existing theories of hegemony can be remedied by conceptualising the complexity of hegemony in a rigorous way using the formal resources of complexity theory. To do so, the thesis first defines the necessary conditions for and properties of complex systems, as investigated by complexity science. It then outlines a general theory of social and political complexity. It develops an original reading of Gramscian hegemony, while critically appraising Laclau and Mouffe’s articulatory variant of the concept. It then brings together insights from the field of complexity theory to rethink the basic concepts of hegemony, before applying the theory to the investigation of the persistence of Neoliberalism after the 2008 financial crisis. In so doing, it establishes the grounds for a new theory of complex hegemony, reworking existing political theory to better explain the complex dynamics of our contemporary world.

In recent years, the contexts in which performances are made have been marked by a global conflict termed a 'war on terror'. The insecurity that this conflict instituted across local and global space intensified anxieties concomitant with a historical period that Zygmunt Bauman has called an 'age of uncertainty'. This thesis draws on the work of Bauman and other political theorists, most notably Giorgio Agamben, to investigate the politics of performance in an age of uncertainty. Following a review of contemporary scholarship exploring the politics of performance, the thesis examines a series of performances that have responded to or otherwise participated in wars on terror. These include: the performed violence of a beheading, the resurgence of 'political theatre' on the London stage and antiwar protest performances during the Iraq war (2003-2008). In addition, the thesis investigates community-based counterterrorism performances in neighbourhoods in the UK targeted as hotspots of terrorist activity following the suicide attacks in London on 7th July 2005. As part of these investigations, a study of the 'war against terrorism' in Northern Ireland (1969-1998), particularly focussing on the counterinsurgency's use of performance as a strategy and tactic of war, highlights the historical continuity of coalitions of performance, crisis and wars on terror. The term 'critical mimesis' is used to generate the conceptual terrain by which the politics of these performances are examined, in particular, to explore how they mirror, reproduce and resist crisis. Motifs of 'refusal' and 'waste' are repeatedly identified as important to the aesthetics and politics of these performances, and comprise the grounds for the thesis' conceptual contribution to understanding a politics of performance in an age of uncertainty. Firstly, the thesis progresses an understanding of performance's political potential as residing in practices of waste. Secondly, this highlights a shift in the focus of politically conscious performance, which moves from concerns for the 'radical' in performance, to reclaiming a conservative ethic and aesthetic as part of performance's radical project. As such, critical mimesis in performance during an age of uncertainty might be understood by means of recourse to concepts of conservation, waste, salvage and restoration, rather than radical excess, transformation or transgression.

When faced with death counts strati ed by age, analysts often calculate a crude mortality rate (CMR) as a single summary measure. This is done by simply dividing total death counts by total population counts. However, the crude mortality rate is not appropriate for comparing different populations due to the significant impact of age on mortality and the possibility of having different age structures for different populations. While a set of age-adjustment methods seeks to collapse age-specific mortality rates into a single measure that is free from the confounding effect of age structure, we focus on one of these methods called "direct age-standardization" method which summarizes and compares age-specific mortality rates by adopting a reference population. While qualitative insights in relation to age-standardization are often discussed, we seek to approximate age-standardized mortality rate of a population based on the corresponding CMR and the 90th quantile of its population distribution. This approximation is most useful when age-specific mortality data is unavailable. In addition, we provide quantitative insights related to age-standardization. We derive our model based on mathematical insights drawn from the explication of exact calculations and validate our model by using empirical data for a large number of countries under a large number of circumstances. We also extend the application of our approximation model to other age-standardized mortality indicators such as cause-specific mortality rate and potential years of life lost. In the second part of the thesis, we consider the formulation of a general risk management procedure, where risk needs to be measured and further mitigated. The formulation admits an optimization representation and requires as input the distributional information about the underlying risk factors. Unfortunately, for most risk factors it is known to be difficult to identify their distribution in full details, and more problematically the risk management procedure can be prone to errors in the input distribution. In particular, one of the most important distribution information is the covariance hat captures the spread and correlation among risk factors. We study the issue of covariance uncertainty in the problem of mitigating tail risk and by admitting an uncertainty set of covariance of risk factors, we propose a robust optimization model which minimizes risk for the worst scenario especially when data is insufficient and the number of risk factors is large. We will then transform our model into a computationally solvable one and test the model using real-world data.

The Question(s) of Youth, of what to do with them, of how to school them, or police them, or regulate them, or house them, or employ them, or prevent them from becoming involved in any number of Risky (sexual, eating, drug (ab)using or peer cultural) practices are questions which have a substantial historical aspect. In the Liberal Democracies at the end of the millennium the Crisis of Youth (at-Risk) is a key marker in theoretical, political and popular debates about Youth. This thesis explores the 'conditions of possibility' which enable discourses of Youth at-Risk to function as true (Henriques et al 1984). I argue that the truth of Youth at-Risk rehearses, in part, the historical truths of Youth as Delinquent, Deviant and Disadvantaged. I will also argue that a historically novel aspect of the truth of Youth at-Risk is that, potentially, every behaviour, every practice, every group of Youth can be constructed in terms of Risk. This thesis is not about the practices, behaviours and dispositions of young people. Rather, my concern is with the ways in which institutionally structured processes of expert knowledge production construct the truths of Youth (at-Risk). The thesis is concerned with the processes by which these largely autonomous systems of expert knowledge production are constitutive of both the 'institutional reflexivity' which characterises contemporary settings, and the forms of identity which emerge in these settings (Giddens 1994 c). I am also concerned with the ways in which these systems of expertise mobilise categories of Risk in diverse attempts to regulate the behaviours and dispositions of certain populations of young people under the conditions of 'reflexive modernization' (Beck, Giddens & Lash 1994). The thesis argues for a productive convergence between theories of reflexive modernization and governmentality. This convergence enables Youth at-Risk to be examined at two (interconnected) levels. In the first instance Risk is understood as constituting a metanarrative in an Age of Manufactured Uncertainty. In the second instance the identification of Risk factors and populations at-Risk will be understood as techniques mobilised in diverse attempts to 'make up' rational, choice making, autonomous, responsible citizens within (Neo)Liberal projects of government (Rose 1996). Foucault's (1991) theory of governmentality foregrounds the practices and relations implicated in the processes whereby 'human beings are made into subjects' (Foucault 1983). Governmentality is a useful and strategic analytic for understanding the diverse attempts by various experts and centres of expertise to regulate young people's identity through the construction of populations of Youth at-Risk. Processes of reflexive modernization are marked by the emergence of a degree of collective awareness that our contemporary conditions of existence are characterised by the thoroughgoing penetration of the social and the natural by reflexive human knowledge. Such a situation leads, not to a position in 'which collectively we are the masters [sic] of our destiny'; but rather to a series of settings in which we are confronted with the possibility that, as a 'consequence of our own doings', the future becomes 'very threatening' (Beck, Giddens & Lash 1994). In problematising the truth of Youth at-Risk this thesis will also engage with various problematisations of Left (critical) intellectual and political practices in domains which take Youth as their object. This thesis is explicitly located in the space of 'critical' (Educational) scholarship in Anglo settings which is structured, historically, by the 'European Marxist social philosophy' of the Frankfurt School and Gramscian (British) Cultural Studies, and French and Italian Feminism and Post (Structuralism and Modernism) (Popkewitz and Brennan 1997). The thesis argues that in order to problematise the truth of Youth at-Risk it is necessary, also, to problematise the processes of truth production mobilised from the Left in an engagement with the material and discursive realities which enable Youth at-Risk to function as a truth. Examining the truth of Youth at-Risk in the frameworks enabled by a convergence of theories of reflexive modernization and governmentality is a contribution to the processes of rethinking the intellectual and political positions which the Left might mobilise at the end of the millennium, when, as Beck (1994 ) argues, 'uncertainty returns'. I will argue that Left intellectual and political practice has no choice but to be open to the uncertain nature of truth telling which characterises processes of reflexive modernization. The tensions generated within these processes are not resolvable. Nor should the 'return of uncertainty' be seen as immobilising in the context of political and intellectual practice. The thesis argues that theories of reflexive modernization and governmentality highlight the dangers of intellectual and political positions which invest heavily in 'modernity's war on ambivalence' (Bauman 1990 b). In settings where the practices and activities of expertise have so thoroughly penetrated the natural and the social, where these processes of colonisation have resulted in the 'return of uncertainty', then the practices and activities of expertise promise, paradoxically, to 'exterminate ambivalence' by telling the truths of Youth at-Risk (Bauman 1990 b). This thesis argues that in an Age of Manufactured Uncertainty the mobilisation of rationally grounded Risk discourses in attempts to regulate Youth emerges as a paradoxical, and dangerous, Quest for Certainty (Bauman 1990 a).

Crowdfunding is a transformative service innovation, a novel and revolutionary way for entrepreneurs to obtain funding for their start-up ventures. This study explores the phenomenon of reward-based crowdfunding in relation to entrepreneurial behaviour and decision-making, as well as the relationship between the entrepreneur and the community. Following a case-study approach, the phenomenon is described based on existing literature and collected empirics from five qualitative in-depth interviews with entrepreneurs performing on Kickstarter. The findings of this study reveal, that reward-based crowdfunding reveals several mechanisms, which attract entrepreneurs to execute their activities and deal with uncertainty in a safer way. These activities refer to (1) independency from traditional investors, (2) creative and effectual reasoning at affordable loss, (3) extending the entrepreneur’s social network via the internet, and (4) utilizing web-based platforms for co-creation of marketing, communication, product design, and brand development. This may lead to adapted forms of entrepreneurship in the future.

This thesis aims to explore aspects of the democratisation of science within the UK. It does this through focusing on the analytic-deliberative practice of participatory risk appraisal (PRA), which emphasises the active involvement of citizens and stakeholders in the framing, assessing, and evaluation stages of complex and uncertain environmental risk policy processes. This was achieved by following professional actors (comprising process-experts, scientific-experts, and decision-makers) through networks currently building around PRA practice across the UK more generally, and in the area of radioactive waste specifically. Analysis shows that professional actors can be seen to belong to an epistemic community comprised of a core group of process experts (researchers and participatory practitioners). This community is in an early stage of development at present and characterised by significant fragmentation between specific actor groupings within it. This coupled with intensely competitive relations between actors means that the community is not learning as effectively as it might. Unless the community makes a more concerted effort to faithfully represent a learning community its potential to democratise science within the UK will remain limited. Closer analysis within the area of radioactive waste provides evidence that community members are influencing the beliefs of decision-making institutions, and enhancing scientific reflexivity, in geographically localised and institutionally specific instances. They have played a central role in bringing about a shift away from a technocratic mode of decision-making prior to 1997, towards one that is more democratic. A key indication of this democratisation is the significant degree to which citizens are being involved in processes of extended peer review, and possibly contributing extended facts, in the framing stage of decision processes within the area. A final insight of the thesis is that community members possess shared understandings about effective PRA. Fifteen shared principles of effective practice are identified in relation four themes: the overall shape of the analytic-deliberative process; the role of science/analysis; access to information and expertise; and the nature of deliberation. The key observation emerging from these principles is that many existing participatory methodologies have not sufficiency considered constructivist perspectives on environmental knowledge. It is argued that effective PRA in postnormal environmental risk contexts depends on a number of specific measures being in place that guard against the 'technocracy of participation'.

A observação de gradientes latitudinais em aspectos da história de vida de aves tem motivado o estudo da evolução e variabilidade das histórias de vida nestes organismos. Um exemplo bem documentado é a variação no tamanho da ninhada, onde aves de latitudes menores tendem a ter ninhadas menores do que os seus homólogos de latitudes altas. Uma hipótese que visa explicar esta variação propõe que a sobrevivência em latitudes tropicais é maior para compensar o tamanho da ninhada menor e evitar a extinção das populações. Esta explicação tem tido grande aceitação e apoio por parte de alguns estudos, mas tem sido questionada por outros que não encontraram taxas de sobrevivência mais elevadas em aves tropicais. De modo implícito, todos estes estudos basearam seus resultados na sobrevivência de indivíduos adultos. As populações com o tamanho da ninhada menor não poderiam crescer da mesma maneira que as populações com ninhadas maiores; portanto, se justifica acreditar que algo deve mudar com a latitude para manter o balanço em tamanho populacional. Na busca por explicações alternativas para a persistência das populações de aves tropicais com relativamente pequenos tamanhos de ninhada, surge outra hipótese que propõe que, se não houver diferenças na sobrevivência de indivíduos adultos entre latitudes, o aspecto fundamental que varia é a sobrevivência juvenil, com sobrevivência maior para os juvenis das zonas tropicais em comparação com os juvenis das zonas temperadas. No entanto, atualmente há pouca evidência que suporta esta conclusão. Os resultados contrastantes desses estudos sugerem a falta de um consenso geral sobre a hipótese de que as aves tropicais têm taxas de sobrevivência mais elevadas do que as aves de regiões temperadas, motivando a formulação de hipóteses alternativas e convidando novos testes de hipótese. Neste estudo, pretendemos a) avaliar o efeito da idade sobre a sobrevivência em aves tropicais, estimando as probabilidades anuais de sobrevivência aparentes idade-específicas para um conjunto de aves passeriformes de sub-bosque na Amazônia central brasileira; e b) contribuir para o debate sobre o gradiente latitudinal na sobrevivência de adultos, comparando nossas estimativas com estimativas de outras latitudes. Para estimar a sobrevivência idade-específica ajustamos aos nossos dados um modelo Cormack-Jolly-Seber (CJS) hierárquico para n espécies, que trata os parâmetros espécie-específicos como efeitos aleatórios, que são estimados e que descrevem todo o conjunto de espécies; para comparação de métodos, ajustamos uma versão de efeitos fixos do modelo. Para a determinação da idade das aves usamos o sistema WRP. Apresentamos uma nova variante do modelo CJS com um parâmetro de mistura para a sobrevivência de aves de idade incerta no momento da primeira captura. Encontramos efeito forte da idade na sobrevivência, com probabilidades de sobrevivência menor para os jovens do que para os adultos; evidência de efeito latitude sobre a sobrevivência, que suporta a hipótese amplamente aceita de variação na sobrevivência com a latitude; e discutimos diferenças metodológicas interessantes entre modelo de efeitos aleatórios e fixos relacionados com a precisão das estimativas e o âmbito de inferência, que nos levam a concluir que os modelos de efeitos aleatórios são os mais adequados para a nossa análise. Concluímos que não é necessário invocar uma hipótese alternativa de maior sobrevivência juvenil nos trópicos a fim de explicar o gradiente latitudinal no tamanho da ninhada.
The observation of latitudinal gradients in bird life history traits has motivated the study of avian life history evolution and variability. A well-documented example is the variation in clutch size, where lower latitude birds tend to have smaller clutches than their higher latitude counterparts. A hypothesis that explains this variation proposes that survival in tropical latitudes is higher to compensate for smaller clutch size and prevent population extinctions. This explanation has had a wide acceptance and support by some studies, but has been questioned by others who have not found such higher survival rates in tropical birds. In an implicit manner, all these studies have based their results on adult survival. Populations with smaller clutch size would not be able to grow as well as populations with larger clutches; therefore one is justified to believe that something else must change with latitude. In the search for alternative explanations to the persistence of tropical bird populations with relatively small clutch sizes it has also been proposed that, if there were no differences in adult survival among latitudes, the fundamental trait that varies is juvenile survival, with higher survival rates for tropical juveniles birds than for temperate ones. However, currently there is little evidence that supports this conclusion. The contrasting results of those studies suggest a lack of a general consensus about the hypothesis that tropical birds have higher survival rates than birds of temperate regions, motivating the formulation of alternative hypotheses, and inviting further tests of the hypothesis. In our study we aim to a) assess the effect of age on survival in a tropical bird community, estimating age-specific annual apparent survival probabilities for a set of passerine understory birds from the central Brazilian Amazon; and b) contribute to the debate about the latitudinal gradient in adult survival by comparing our adult survival estimates to estimates of temperate-zone adult survival probabilities. To estimate the age-specific survival we fit to our data a hierarchical multispecies Cormack-Jolly-Seber (CJS) model for n species, that treats species-specific parameters as random effects that are estimated and that describe the whole assemblage of species; for comparison of methods, we also fit a fixed-effects version of the model. To age birds we use the cycle-based WRP system. We introduce a novel variant of CJS model with a mixture component for the survival of birds of uncertain age at the time of banding. We found strong effect of age on survival, with juveniles surviving less than adults; evidence of latitude effect on survival, that supports the widely accepted hypothesis of variation on survival with latitude; and methodological differences between random and fixed effects model related to precision of estimates and scope of inference, that lead us to conclude that random-effects models are more appropriate for our analysis. We conclude that there is no reason for an alternative latitudinal trend in juvenile survival to account for the general trend in clutch size.

Netflix and other streaming services have grown immensely since they started offering online streaming. In this paper I present a correlation matrix using ticket sales at the domestic box office and the number of Netflix subscribers. They are shown to be negatively correlated with one another, supporting many previous researchers’ thoughts on the topic. I also show using two OLS regressions with data from movies released in 2006-2007 and 2017-2018 that being a part of a franchise has a stronger correlation with increased revenue in the latter model compared to the previous one. In the models one can also see that the general quality of a movie, as measured by IMDb rating, is associated with a higher increase in revenue in the latter model. I argue that this is due to consumers being inclined to watch what they perceive to be high-quality movies in the theaters in the latter model as they can conveniently watch movies of a poorer quality on their streaming service, an option that was not available to the same extent previously. I also argue that consumers are more willing to commit to going to the cinema for a franchise movie, especially in the Marvel cinematic universe, as they are often effects driven movies which are better experienced on a large screen. The budget variable is significant in both models, but the coefficient is much smaller in the second model. I argue that this is due to the fact that a higher budget is required for movies released in 2017-2018 to maintain the same level of revenue as in 2006 and 2007 due to the competition that have come from streaming services. However, I conclude that more research is necessary before drawing definite conclusions as the market for cinema is highly uncertain and difficult to estimate accurately.

At present, carbon sequestration in terrestrial ecosystems slows the growth rate of atmospheric CO₂ concentrations, and thereby reduces the impact of anthropogenic fossil fuel emissions on the climate system. Changes in climate and land use affect terrestrial biosphere structure and functioning at present, and will likely impact on the terrestrial carbon balance during the coming decades - potentially providing a positive feedback to the climate system due to soil carbon releases under a warmer climate. Quantifying changes, and the associated uncertainties, in regional terrestrial carbon budgets resulting from these effects is relevant for the scientific understanding of the Earth system and for long-term climate mitigation strategies.

A model describing the relevant processes that govern the terrestrial carbon cycle is a necessary tool to project regional carbon budgets into the future. This study (1) provides an extensive evaluation of the parameter-based uncertainty in model results of a leading terrestrial biosphere model, the Lund-Potsdam-Jena Dynamic Global Vegetation Model (LPJ-DGVM), against a range of observations and under climate change, thereby complementing existing studies on other aspects of model uncertainty; (2) evaluates different hypotheses to explain the age-related decline in forest growth, both from theoretical and experimental evidence, and introduces the most promising hypothesis into the model; (3) demonstrates how forest statistics can be successfully integrated with process-based modelling to provide long-term constraints on regional-scale forest carbon budget estimates for a European forest case-study; and (4) elucidates the combined effects of land-use and climate changes on the present-day and future terrestrial carbon balance over Europe for four illustrative scenarios - implemented by four general circulation models - using a comprehensive description of different land-use types within the framework of LPJ-DGVM.

This study presents a way to assess and reduce uncertainty in process-based terrestrial carbon estimates on a regional scale. The results of this study demonstrate that simulated present-day land-atmosphere carbon fluxes are relatively well constrained, despite considerable uncertainty in modelled net primary production. Process-based terrestrial modelling and forest statistics are successfully combined to improve model-based estimates of vegetation carbon stocks and their change over time. Application of the advanced model for 77 European provinces shows that model-based estimates of biomass development with stand age compare favourably with forest inventory-based estimates for different tree species. Driven by historic changes in climate, atmospheric CO₂ concentration, forest area and wood demand between 1948 and 2000, the model predicts European-scale, present-day age structure of forests, ratio of biomass removals to increment, and vegetation carbon sequestration rates that are consistent with inventory-based estimates. Alternative scenarios of climate and land-use change in the 21^st century suggest carbon sequestration in the European terrestrial biosphere during the coming decades will likely be on magnitudes relevant to climate mitigation strategies. However, the uptake rates are small in comparison to the European emissions from fossil fuel combustion, and will likely decline towards the end of the century. Uncertainty in climate change projections is a key driver for uncertainty in simulated land-atmosphere carbon fluxes and needs to be accounted for in mitigation studies of the terrestrial biosphere.

Kohlenstoffspeicherung in terrestrischen Ökosystemen reduziert derzeit die Wirkung anthropogener CO₂-Emissionen auf das Klimasystem, indem sie die Wachstumsrate der atmosphärischer CO₂-Konzentration verlangsamt. Die heutige terrestrische Kohlenstoffbilanz wird wesentlich von Klima- und Landnutzungsänderungen beeinflusst. Diese Einflussfaktoren werden sich auch in den kommenden Dekaden auf die terrestrische Biosphäre auswirken, und dabei möglicherweise zu einer positiven Rückkopplung zwischen Biosphäre und Klimasystem aufgrund von starken Bodenkohlenstoffverlusten in einem wärmeren Klima führen. Quantitative Abschätzungen der Wirkung dieser Einflussfaktoren - sowie der mit ihnen verbundenen Unsicherheit - auf die terrestrische Kohlenstoffbilanz sind daher sowohl für das Verständnis des Erdsystems, als auch für eine langfristig angelegte Klimaschutzpolitik relevant.

Um regionale Kohlenstoffbilanzen in die Zukunft zu projizieren, sind Modelle erforderlich, die die wesentlichen Prozesse des terrestrischen Kohlenstoffkreislaufes beschreiben. Die vorliegende Arbeit (1) analysiert die parameterbasierte Unsicherheit in Modellergebnissen eines der führenden globalen terrestrischen Ökosystemmodelle (LPJ-DGVM) im Vergleich mit unterschiedlichen ökosystemaren Messgrößen, sowie unter Klimawandelprojektionen, und erweitert damit bereits vorliegende Studien zu anderen Aspekten der Modelunsicherheit; (2) diskutiert unter theoretischen und experimentellen Aspekten verschiedene Hypothesen über die altersbedingte Abnahme des Waldwachstums, und implementiert die vielversprechenste Hypothese in das Model; (3) zeigt für eine europäische Fallstudie, wie Waldbestandsstatistiken erfolgreich für eine verbesserte Abschätzung von regionalen Kohlenstoffbilanzen in Wäldern durch prozessbasierten Modelle angewandt werden können; (4) untersucht die Auswirkung möglicher zukünftiger Klima- und Landnutzungsänderungen auf die europäische Kohlenstoffbilanz anhand von vier verschiedenen illustrativen Szenarien, jeweils unter Berücksichtigung von Klimawandelprojektionen vier verschiedener Klimamodelle. Eine erweiterte Version von LPJ-DGVM findet hierfür Anwendung, die eine umfassende Beschreibung der Hauptlandnutzungstypen beinhaltet.

Die vorliegende Arbeit stellt einen Ansatz vor, um Unsicherheiten in der prozessbasierten Abschätzung von terrestrischen Kohlenstoffbilanzen auf regionaler Skala zu untersuchen und zu reduzieren. Die Ergebnisse dieser Arbeit zeigen, dass der Nettokohlenstoffaustausch zwischen terrestrischer Biosphäre und Atmosphäre unter heutigen klimatischen Bedingungen relativ sicher abgeschätzt werden kann, obwohl erhebliche Unsicherheit über die modelbasierte terrestrische Nettoprimärproduktion existiert. Prozessbasierte Modellierung und Waldbestandsstatistiken wurden erfolgreich kombiniert, um verbesserte Abschätzungen von regionalen Kohlenstoffvorräten und ihrer Änderung mit der Zeit zu ermöglichen. Die Anwendung des angepassten Modells in 77 europäischen Regionen zeigt, dass modellbasierte Abschätzungen des Biomasseaufwuchses in Wäldern weitgehend mit inventarbasierten Abschätzungen für verschiede Baumarten übereinstimmen. Unter Berücksichtigung von historischen Änderungen in Klima, atmosphärischem CO₂-Gehalt, Waldfläche und Holzernte (1948-2000) reproduziert das Model auf europäischer Ebene die heutigen, auf Bestandsstatistiken beruhenden, Abschätzungen von Waldaltersstruktur, das Verhältnis von Zuwachs und Entnahme von Biomasse, sowie die Speicherungsraten im Kohlenstoffspeicher der Vegetation. Alternative Szenarien von zukünftigen Landnutzungs- und Klimaänderungen legen nahe, dass die Kohlenstoffaufnahme der europäischen terrestrischen Biosphäre von relevanter Größenordnung für Klimaschutzstrategien sind. Die Speicherungsraten sind jedoch klein im Vergleich zu den absoluten europäischen CO₂-Emissionen, und nehmen zudem sehr wahrscheinlich gegen Ende des 21. Jahrhunderts ab. Unsicherheiten in Klimaprojektionen sind eine Hauptursache für die Unsicherheiten in den modellbasierten Abschätzungen des zukünftigen Nettokohlenstoffaustausches und müssen daher in Klimaschutzanalysen der terrestrischen Biosphäre berücksichtigt werden.

Pension schemes are facing more difficulties on matching their underlying liabilities with assets, mainly due to faster mortality improvements for their underlying populations, better environments and medical treatments and historically low interest rates. Given most of the pension schemes are relatively much smaller than the national population, modelling and forecasting the small populations' longevity risk become urgent tasks for both the industrial practitioners and academic researchers. This thesis starts with a systematic analysis on the influence of population size on the uncertainties of mortality estimates and forecasts with a stochastic mortality model, based on a parametric bootstrap methodology with England and Wales males as our benchmark population. The population size has significant effect on the uncertainty of mortality estimates and forecasts. The volatilities of small populations are over-estimated by the maximum likelihood estimators. A Bayesian model is developed to improve the estimation of the volatilities and the predictions of mortality rates for the small populations by employing the information of larger population with informative prior distributions. The new model is validated with the simulated small death scenarios. The Bayesian methodologies generate smoothed estimations for the mortality rates. Moreover, a methodology is introduced to use the information of large population for obtaining unbiased volatilities estimations given the underlying prior settings. At last, an empirical study is carried out based on the Scotland mortality dataset.

In the context of “testing laboratory” one of the most important aspect to deal with is the measurement result. Whenever decisions are based on measurement results, it is important to have some indication of the quality of the results. In every area concerning with noise measurement many standards are available but without an expression of uncertainty, it is impossible to judge whether two results are in compliance or not. ISO/IEC 17025 is an international standard related with the competence of calibration and testing laboratories. It contains the requirements that testing and calibration laboratories have to meet if they wish to demonstrate that they operate to a quality system, are technically competent and are able to generate technically valid results. ISO/IEC 17025 deals specifically with the requirements for the competence of laboratories performing testing and calibration and for the reporting of the results, which may or may not contain opinions and interpretations of the results. The standard requires appropriate methods of analysis to be used for estimating uncertainty of measurement. In this point of view, for a testing laboratory performing sound power measurement according to specific ISO standards and European Directives, the measurement of uncertainties is the most important factor to deal with. Sound power level measurement, according to ISO 3744:1994 , performed with a limited number of microphones distributed over a surface enveloping a source is affected by a certain systematic error and a related standard deviation. Making a comparison of measurement carried out with different microphone arrays is difficult because results are affected by systematic errors and standard deviation that are peculiarities of the number of microphones disposed on the surface, their spatial position and the complexity of the sound field. A statistical approach could give an overview of the difference between sound power level evaluated with different microphone arrays and an evaluation of errors that afflict this kind of measurement. Despite the classical approach that tend to follow the ISO GUM this thesis present a different point of view of the problem related to the comparison of result obtained from different microphone arrays.

Submitted by Leticia Schettini (leticia@ufrrj.br) on 2016-09-19T15:16:21Z No. of bitstreams: 1 2010 - Juarez Vicente.pdf: 1012625 bytes, checksum: 30ce03687174fc4cf4226e455adde13a (MD5)
Made available in DSpace on 2016-09-19T15:16:21Z (GMT). No. of bitstreams: 1 2010 - Juarez Vicente.pdf: 1012625 bytes, checksum: 30ce03687174fc4cf4226e455adde13a (MD5) Previous issue date: 2010-05-07
From the scientific viewpoint, the word ?uncertainty? expresses doubt about an analytic result. The implementation of the concept of uncertainty of measurement is a crucial step that the Brazilian laboratories must take in the process for obtaining the certification of the ability to perform essays in accordance with the Brazilian technical norm ABNT NBR ISO/IEC 17025. Regardless the technical area of application, the determination of the uncertainty of measurement associated with the result of an analysis is extremely important, especially in the food industry. The expanded uncertainty is related with the degree of reliability of an analytical result, and by means of this information it is possible to evaluate if the result of an analysis is consistent, i.e., if the uncertainty associated to the measurement remains inside an acceptable range. When the percentage of uncertainty exceeds a threshold, it is necessary to find the process variables that more intensely contribute to increasing the uncertainty and, in the sequence, to take corrective actions in order to minimize the impact caused for those variables over the uncertainty of measurement. The aim of this study was to detect the uncertainty of measurement associated with the analysis of total reducing sugars (TRS) by the Lane-Eynon method. The equipments used were analytical and semi analytical balances, burettes with 10mL and 25mL, and the food matrix studied was wild honey. To perform the calculations of the standard uncertainty, u, information about the uncertainty of the laboratory materials used in the analysis ? obtained from the certificate of calibration. The combined uncertainty, uc, was obtained by deriving the influence factors and considering, if necessary, the effective degree of freedom, ?eff, as stated in the Welch-Satterthwaite equation. The expanded uncertainty, U, was obtained by multiplying uc by the appropriate coverage factor, k = 2 (at level of confidence of 95,45%). The results showed that the expanded uncertainty obtained for the analysis of TRS was less than 2,0% when the analytical balance was used. The process variable having the greatest impact was the volume (close to 80,0%), followed by the title (close to 20,0%). The analysis of the expanded uncertainty obtained for the analysis of TRS when the semi analytical balance, and 10mL as well as 25mL burettes were used provided reliable results. However, care must be taken in such a combination of equipments, especially when using the 25mL burettes, since the percentage of uncertainty was great than 3,5%, too close to the limit established by the Codex Alimentarius, 4,0%. It was observed that, in this case, the variable having the greatest impact on the uncertainty was the title, with 79,82% (10mL burettes), and 87,10% (25mL burettes).
Do ponto de vista t?cnico-cient?fico, a palavra ?incerteza? expressa a d?vida em rela??o a um resultado anal?tico. A aplica??o do conceito de incerteza de medi??o ? fundamental para os laborat?rios brasileiros que almejam obter o reconhecimento da capacidade de realiza??o de ensaios em conformidade com a norma ABNT NBR ISO/IEC 17025. Independentemente da ?rea de atua??o, ? de extrema import?ncia o estudo e o conhecimento da incerteza de medi??o associada a um resultado de an?lise, em particular quando aplicado ? ind?stria de alimentos. A incerteza expandida informa o grau de confiabilidade de um resultado anal?tico e, atrav?s dela, ? poss?vel avaliar, a um n?vel de abrang?ncia estabelecido, se o resultado de uma an?lise transmite credibilidade, ou seja, se o valor da incerteza est? em uma faixa de concentra??o aceit?vel ou n?o. Quando o percentual de incerteza ultrapassa o limite aceit?vel, ? necess?rio conhecer quais as vari?veis do m?todo que mais contribuem para a incerteza e executar as medidas corretivas a fim de minimizar este impacto e, consequentemente, reduzir a incerteza total. O objetivo geral deste trabalho foi determinar a incerteza expandida associada ? an?lise titulom?trica de a??cares redutores totais (ART) pelo m?todo de Lane-Eynon, tendo como matriz uma amostra de mel, utilizando balan?a anal?tica e semi anal?tica e buretas de 10mL e 25mL. Para o c?lculo da incerteza padr?o (u), utilizaram-se os dados obtidos nos certificados de calibra??o de equipamentos e vidrarias empregados na an?lise. A incerteza combinada ( ) foi obtida derivando os fatores de influ?ncia e considerando, quando necess?rio, o grau de liberdade efetivo (?eff), dado pela Equa??o de Welch-Satterthwaite. Obteve-se a incerteza expandida (U) multiplicando-se por 2 (dois) o valor de para um n?vel de confian?a de 95,45%. Os resultados obtidos mostraram que a incerteza expandida de ART utilizando balan?a anal?tica n?o foi significativa (<2%) e que a vari?vel que mais influenciou foi o volume de amostra gasto (~80%), seguido do T?tulo (~20%). A an?lise da incerteza expandida de ART obtida com balan?a semi anal?tica e buretas de 10mL e 25mL gerou resultados confi?veis. No entanto, deve haver cautela neste caso, especialmente ao se utilizar bureta de 25mL, visto que o valor percentual de incerteza superou 3,5%. Observa-se que a vari?vel que mais contribui para a incerteza foi o T?tulo com 79,82% (bureta de 10mL) e 87,10% (bureta de 25mL).

La tesi è divisa in quattro manoscritti. Lo scopo è lo studio di tre aspetti, come casi-studio indipendenti, all’interno della gestione della catena alimentare dai mangimi al latte. Il primo manoscritto riguarda la fortificazione del latte bovino con iodio e selenio allo scopo di migliorare la qualità del latte e dei suoi derivati; il secondo riguarda la contaminzione dei mangimi con melamina come fattore di rischio per l’industria lattiero-casearia e la salute pubblica. Gli ultimi due lavori sono corollari alla qualità del latte derivante dallo iodio: ovvero un confronto analitico tra procedure di determinazione dello iodio in latte crudo, e uno studio di speciazione dello iodio inorganico nel latte crudo fortificato. Il primo lavoro offre informazioni per meglio comprendere i fattori coinvolti nel miglioramento della concentrazione dello iodio e del selenio nel latte a seguito di una fortificazione della dieta animale. Riguardo la melamina, lo studio conferma il passaggio di essa dai mangimi al latte e la sua rapida escrezione anche a livelli bassi di ingestione da parte dell’animale; uno scarso passaggio dal latte al formaggio. Il terzo lavoro mostra che, per analisi dello iodio con ICP-MS, l’estrazione dell’elemento con soluzione d’ammoniaca è una valida alternativa al metodo ufficiale con TMAH. La speciazione dello iodio inorganico nel latte scremato è un’operazione possibile utilizzando delle diluizioni con soluzione d’ammoniaca (quarto manoscritto).
The thesis is divided into 4 manuscripts. The aim is to study three aspects, as independent case studies, within the quality management of feed-for-food system. The first manuscript is about the fortification of feeds with iodine and selenium to improve the quality of cow’s milk and derivatives; the second one investigates the contamination of feeds with melamine as risk factor for dairy industries and human health. The last two works are corollaries to the iodine-linked quality of milk: i.e. a comparison between analytical procedures for the determination of iodine in raw milk, and a speciation study of iodine in fortified milk. The first work helps to better understand factors involved in improvement of milk iodine and selenium concentration and CO following supplementation with inorganic sources. Regarding melamine, the study confirmed the pathway for its transmission from feed to milk and its rapid excretion, also at a very low level of melamine ingestion by cows; and a low transfer from milk to cheese. The third study shows that the ammonia extraction of iodine is a valid alternative to the official method with TMAH for iodine determination in milk, by using ICP-MS. The speciation of inorganic iodine in skimmed milk is feasible by using ammonia dilution (fourth manuscript).

Le travail presente dans ce memoire a pour principal objectif d'etablir une methodologie permettant d'evaluer les imprecisions sur les resultats de modelisation et de l'appliquer a l'estimation de la vulnerabilite de la ressource en eau face a des pollutions diffuses d'origine agricole. Dans une premiere partie, nous presentons les principaux phenomenes physiques lies au devenir des produits phytosanitaires dans les sols (transport, retention, transformation, volatilisation, reprise par les plantes. . . ) et nous ne manquerons pas de rappeler les differentes imprecisions concernant les caracteristiques chimiques des produits phytosanitaires, les proprietes du sol et les equations utilisees pour modeliser ces differents phenomenes. Puis, apres avoir mis en evidence l'importance de la prise en compte de ces differentes imprecisions pour evaluer celles sur les resultats de modelisation, et avoir montre les limites des methodes classiques d'analyse d'incertitude, nous developpons une methode fondee sur les sous-ensembles flous et sur la logique floue. Cette methode permet de quantifier les imprecisions sur les resultats issus des modeles mathematiques et d'evaluer la confiance que l'on peut accorder a ces derniers. Plusieurs applications, utilisant des modeles simples de diagnostic, sur le bassin versant du grand morin (region parisienne) et sur celui de pearl harbor (hawai), permettent de comparer les imprecisions sur les resultats obtenues d'une part avec des methodes classiques et d'autre part avec la methode fondee sur les sous-ensembles flous. Ces comparaisons mettent en avant les avantages de cette derniere par rapport aux methodes classiques, presentent differents indices d'evaluation de la vulnerabilite (drastic, af) et du potentiel a la lixiviation (rf) pour deux produits phytosanitaires (atrazine et diuron), et soulignent a nouveau l'importance de la prise en compte des imprecisions dans les resultats de modelisation. La derniere partie de ce travail consiste a valider notre methodologie fondee sur la logique floue sur une application consistant a calculer le flux convectif d'atrazine dans la zone non saturee du bassin du grand morin en utilisant le modele mathematique leachmp. Il ressort de cette application, qu'il est fondamental d'associer a la valeur moyenne issue d'un modele mathematique, un intervalle de variation de cette valeur defini par une coupe de niveau alpha et le degre d'appartenance minimum des valeurs de l'intervalle au sous-ensemble flou des solutions.

碩士
國立臺灣師範大學
美術學系
101
The study of “human beings” is the inspiration of my art work. The main idea of my thesis is to describe the interactions between people and the surroundings. People show their feelings by physical reaction. The thesis is going to observe the things around our daily life in order to generalize people’s states of mind and emotions. It will be a huge but interesting case to embody the symbolic icon and abstract emotions from human beings into practical painting. Thus , people become premier subject of painting instead of scenery. Different stages of life and time make people’s feeling and behavior differ. The thesis wants to provide an association between ”the past” and “the future” by illustrating the portrait of present. People also provide a symbolic meaning to the natural scenes they’ve seen due to their growing background and living style. I hope I can find out a symbolic language in the way to present the general ideas with all the mankind. The following statement is based on the chapters of my thesis: Chapter One: "Introduction" elaborates individual research motivation, purpose, content and scope of research methods. Chapter Two: Collecting relevant theories and information about the feelings of uncertainty and anxiety of age that come from western and eastern. Instability of balance, turmoil tranquility and the symbol of gesture are three main topic discussed in this paper. Use those kinds of theories to establish the goal of showing individuality and directions of this study. Chapter Three: Comparing different styles and context of painting depending on the conclusion of Chapter Two. Chapter Four: Creation and analysis about the work. Chapter Five: Generalizing the conclusion of research and looking forward to the future progress.

While finances are known to be a source of uncertainty for couples (Knobloch, 2008), the specific sources of financial ambiguity and the ways in which they are appraised and negotiated have not been explored. Framed by the lens of Uncertainty Management Theory (UMT; Brashers, 2001), the current study used face-to-face, semi-structured interviews of 40 diverse participants in married or cohabiting relationships to provide new insight into uncertainty management. The investigation uncovered the types of uncertainty experienced by participants (economic, personal, family, communication, and chronic), the ways in which people managed uncertainty (reducing, maintaining, and adapting to it through a variety of practical strategies), and barriers to uncertainty management (information, time management, sociocultural, and communication obstacles), shedding light on why people are (not) successful in managing their finances. Consistent with the tenets of UMT (Brashers, 2001), communication (or lack thereof) was critical to the process of uncertainty management, particularly with respect to reducing and maintaining uncertainty. However, this study uniquely found that collective negotiation of financial uncertainty was particularly salient. In many ways, financial uncertainty management can be conceptualized as a joint enterprise. Just as individuals negotiate uncertainty by seeking information through computer-mediated communication (e.g., the internet), mass media (e.g., magazines), and external interpersonal sources (e.g., financial advisors), this investigation found that people frequently negotiated their uncertainty with their romantic partner through communal coping. This study provides important insight into the ways in which financial uncertainty can influence people's communication, behavior, and relationships and proposes extending the theory to take into account the role that dyads, culture, and individual factors can play in shaping uncertainty management.
text

碩士
國立清華大學
資訊工程學系
97
The appearance of human changes with age significantly. It is still a big challenge to estimate age from the appearance of facial images. In this work, we focus on the application of age estimation from face images. We try to improve the accuracy of age estimation from two ways. First, we propose facial feature projection from uncertain label. By considering the continuity of age labels in facial feature projection step, we extract better features to represent age characteristics. In addition, we propose Bayesian age estimation framework by combining probabilistic model and age regression. We can incorporate any extra information into the unified age estimation framework easily. From the experimental results, the proposed Bayesian age estimation using facial feature projection from uncertain label can perform better than other existing age estimation methods.

碩士
國立東華大學
資訊工程學系
101
Recently age estimation has attracted many researchers’ attention due to its diverse applications in daily life. Many different the aging extraction models and age estimation models have been proposed; however, the estimation accuracy is influenced by two issues of aging diversity and insufficient aging data. This work focuses on the problem of insufficient aging data. In general, it is not easy to get the sufficient aging images for database; besides, labeling all the aging images requires large human labor. These reasons may limit the generalization ability of learning algorithm on the insufficient aging data. To maintain the estimation performance under a limited amount of labeled samples, we propose a novel age estimation algorithm, Uncertain Labels on Laplacian Regularized Least Squares (UL-LapRLS) algorithm, which is based on a semi-supervised framework with uncertain labels. This approach improves the generalization ability of estimation model by learning both labeled and unlabeled data in Manifold Regularization (MR) algorithm. Since the faces in adjacent ages have similar appearance, this work labels each image with uncertain label which covers a number of age classes instead of exact age. Besides, we also take into account the correlation between the age labels by adding the correction term into the regularization. The work uses AAM parameters as the image features and performs the experiments on the FG-NET database through the LOPO(Leave-One-Person-Out) mode. The results demonstrate that the UL-LapRLS with all labeled samples is better than previous supervised methods, and even performs well on reductive number of labeled samples, which proves that semi-supervised framework with uncertain labels can improve the performance on insufficient aging data.