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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
641

H∞ Filter Design for Classes of Nonlinear Systems

Movahhedi, Omid Unknown Date
No description available.
642

Growth, Carbon Dioxide Emissions, Climate and Wellbeing

Grunewald, Nicole 31 August 2012 (has links)
Die fünf Essays dieser Dissertation behandeln Themen aus dem Bereich der Entwicklungs- und Umweltökonomie. Alle Essays analysieren wie die Produktion von CO2 Emissionen beeinflusst oder reguliert werden kann. Das Treibhausgas CO2 ist eine der größten Externalitäten der Geschichte menschlicher Entwicklung. Die einzelnen Essays zeigen wie lokale Klimaveränderungen das menschliche Wohlbefinden beeinflussen und welche monetären Kosten mit einem Anstieg der Durchschnittstemperatur in Lateinamerika verbunden sind. Außerdem betrachten die Essays Hauptdeterminanten von CO2 Emissionen auf haushalts- oder nationalem Niveau, und bestimmen den Erfolg aktueller Klimapolitik um CO2 Emissionen zu reduzieren. Das letzte Essay betrachtet die momentane und zukünftige Verteilung von CO2 Emissionen wenn verschiedene Politikszenarien realisiert werden würden. Das erste Essay befasst sich mit dem Effekt von klimatischen Veränderungen auf das Wohlfahrtsniveau in Lateinamerika. Als Wohlfahrtsmaß kommen dabei subjektive Selbstaussagen zum Einsatz. Subjektive Wohlfahrt erfasst nicht nur Veränderungen im Einkommen, sondern auch Veränderungen in anderen Lebensbereichen wie dem Zugang zu Bildung oder Gesundheitseinrichtungen. Generell kommt die Studie zu dem Schluss, dass eine Temperatur im Bereich von 20 Grad Celsius und Niederschlag bis 247mm optimal sind. Höhere monatliche Durchschnittstemperaturen oder Niederschläge sind mit Wohlfahrtsverlusten verbunden. Eine globale Erwärmung von mehr als 2 Grad Celsius wird mit Wohlfahrtsverlusten in Lateinamerika einhergehen. Das zweite Essay analysiert Haushaltsemissionen in Form des Kohlenstoff-Fußabdrucks in Indien. Dabei liegt das Augenmerk auf dem Effekt von Einkommenswachstum und sozio- ökonomischen Veränderungen innerhalb der Haushalte. Ein höheres Haushaltseinkommen führt zu einem stärkeren Konsumverhalten aber gleichzeitig auch zu weniger CO2- intensiven Konsummustern. Dennoch kann der Mehrkonsum an CO2-armen Gütern, wie zum Beispiel Bildung, den Anstieg der Haushaltsemissionen, aufgrund höheren Einkommens, nicht kompensieren. Das dritte Essay betrachtet in wie fern aktuelle internationale Klimapolitik einen Einfluss auf CO2 Emissionen genommen hat. Dabei zeigt sich, dass Länder, welche Verpflichtungen im Rahmen des Kyoto Protokolls eingegangen sind, im Durschnitt 6.5% weniger CO2 emittiert haben, als vergleichbare Länder mit ähnlichem Einkommens- und Bevölkerungswachstum aber ohne Verpflichtungen. Das vierte Essay geht auf die Hauptdeterminante des CO2 Emissionswachstums ein, nämlich Einkommen. Dabei wird aber nicht nur der Effekt von Veränderungen im Einkommen, sondern auch der Effekt von Veränderungen in der Einkommensverteilung auf CO2 Emissionen untersucht. Einkommensungleichheit wirkt sich abhängig vom gegenwertigen Ungleichheitsniveau auf CO2 Emissionen aus. Für Länder mit einer hohen Einkommensungleichheit ist der Effekt positiv, das heißt mit sinkender Einkommensungleichheit sinken CO2 Emissionen. Für Länder mit niedriger Ungleichheit ist der Effekt negativ. Ein weiterer Abbau der Einkommensungleichheit würde dort mit steigenden CO2 Emissionen einhergehen. Das fünfte Essay befasst sich mit der globalen Verteilung von pro Kopf CO2 Emissionen. Dabei geht es darum inwiefern der Energiemix und der sektorale Aufbau einzelner Volkswirtschaften zu dieser ungleichen Verteilung von pro Kopf CO2 Emissionen beigetragen haben. Der Abbau schwerer Industrie in OECD Ländern und der verstärkte Einsatz von Kohle in nicht-OECD Ländern haben dabei zu einem Rückgang der globalen Ungleichheit in CO2 Emissionen geführt. Langfristig gesehen kann es sein, dass die Emissionsungleichheit ab 2040 wieder steigen wird. Jedes Essay trägt in seinem Feld zur betreffenden Literatur bei. Die Essays analysieren wie jegliche ökonomische Aktivität (hauptsächlich Konsum) CO2 Emissionen verursachen, welche wiederum für Veränderungen im Klima verantwortlich gemacht werden. Diese Veränderungen im Klima gehen mit lokalen Wohlfahrtsverlusten einher. Nationale Politikmaßnahmen wie zum Beispiel Maßnahmen zur Einkommensumverteilung können einen ambivalenten Einfluss auf CO2 Emissionen haben. Politikmaßnahmen um das Konsumverhalten und Konsummuster zu beeinflussen könnten ein effizientes Mittel zur Regulierung von CO2 Emissionen in reichen Ländern darstellen. Generell könnten internationale Klimapolitikmaßnahmen nationale Politikmaßnahmen katalysieren.
643

Causes and consequences of intra-household inequality on poverty determination: The case of semi-urban Indo-Fijian households

Sunil Kumar Unknown Date (has links)
The thesis considers two pertinent questions about poverty in Fiji. One is about the accuracy of the poverty measures calculated by the concerned organisations and this relates to the use of equivalence scales and the general style of analysis. The other more intricate question is the disregard for poverty due to intra-family distribution asymmetries. Such miscalculations of poverty arise due use of average household per capita expenditure to represent consumption. This research attempts to answer the question of whether the tendency to underestimate the incidence of poverty by disregarding intra-family inequality is significant. Furthermore, it attempts to determine the causes of these inequalities. The issue is whether the classical method of data analysis (using the family as a unit) is the ideal way of analysing poverty and distribution in societies where large family structures exist and government relief remains minimal. To determine the household inequalities, household expenditures have been disaggregated into individualised expenditures. The individualised consumption expenditure is analysed and compared with the outcomes of aggregate household expenditure data. The analysis provides overwhelming evidence for underestimation of poverty when household consumption expenditures are used.
644

Causes and consequences of intra-household inequality on poverty determination: The case of semi-urban Indo-Fijian households

Sunil Kumar Unknown Date (has links)
The thesis considers two pertinent questions about poverty in Fiji. One is about the accuracy of the poverty measures calculated by the concerned organisations and this relates to the use of equivalence scales and the general style of analysis. The other more intricate question is the disregard for poverty due to intra-family distribution asymmetries. Such miscalculations of poverty arise due use of average household per capita expenditure to represent consumption. This research attempts to answer the question of whether the tendency to underestimate the incidence of poverty by disregarding intra-family inequality is significant. Furthermore, it attempts to determine the causes of these inequalities. The issue is whether the classical method of data analysis (using the family as a unit) is the ideal way of analysing poverty and distribution in societies where large family structures exist and government relief remains minimal. To determine the household inequalities, household expenditures have been disaggregated into individualised expenditures. The individualised consumption expenditure is analysed and compared with the outcomes of aggregate household expenditure data. The analysis provides overwhelming evidence for underestimation of poverty when household consumption expenditures are used.
645

The Educational Opportunity Structure and Stratification of College Counseling at Southern California Public High Schools

Ceron, Adriana 01 January 2018 (has links)
This study documents how organizational strategies underlying college counseling departments modify counselors’ ability to perform their academic and college advising duties. To examine this, fifteen semi-structured, in-depth interviews with public high school counselors in Southern California were conducted. A district’s commitment to college access and opportunity, as well as parents’ expectations for maintaining a college-going culture, shaped the nature of college counseling and organizational habitus in a school. Counselors reported that access to different forms of institutional support and resources diminish or exacerbate the structural constraints known to surface in public schools. This influenced when and how counselors advised students, which offered different views of the educational opportunity structure. Additionally, findings indicate that both college preparation programs and culturally sensitive counselors work to remedy educational disparities and increase the college enrollment rates of working-class minority students.
646

On impatience, education, returns, and inequality

Guimarães, Guido Couto Penino 13 April 2015 (has links)
Submitted by Guido Couto Penido Guimarães (guido.guimaraes@fgvmail.br) on 2015-05-15T19:21:28Z No. of bitstreams: 1 20150516035825408.pdf: 2427180 bytes, checksum: 7d04b8fe0a5b09cdefb5e1395b3e7dbd (MD5) / Approved for entry into archive by BRUNA BARROS (bruna.barros@fgv.br) on 2015-05-20T14:02:22Z (GMT) No. of bitstreams: 1 20150516035825408.pdf: 2427180 bytes, checksum: 7d04b8fe0a5b09cdefb5e1395b3e7dbd (MD5) / Approved for entry into archive by Marcia Bacha (marcia.bacha@fgv.br) on 2015-06-12T20:07:15Z (GMT) No. of bitstreams: 1 20150516035825408.pdf: 2427180 bytes, checksum: 7d04b8fe0a5b09cdefb5e1395b3e7dbd (MD5) / Made available in DSpace on 2015-06-12T20:07:40Z (GMT). No. of bitstreams: 1 20150516035825408.pdf: 2427180 bytes, checksum: 7d04b8fe0a5b09cdefb5e1395b3e7dbd (MD5) Previous issue date: 2015-04-13 / In this paper we investiga te the impact of initial wealth anel impatience heterogeneities, as wcll as differential access to financia! markets on povcrty anel inequality, anel cvaluate some mechanisms that could be used to alleviate situations in which these two issues are alarming. To address our qucstion we develop a dynamic stochastic general cquilibrium modo! of educational anel savings choicc with heterogeneous agents, where individuais differ in their initial wealth anel in their discount factor. We find that, in the long run, more patient households tend to be wealthier anel more educated. However, our baseline model is not able to give as much skewness to our income distribution as it is rcquircd. We then propose a novel returns structure based on empírica! observation of heterogeneous returns to different portfolios. This modification solves our previous problem, evidencing the importance of the changes made in explaining the existing levels of inequality. Finally, we introducc two kinds of cash transfers programs- one in which receiving thc benefit is conditional on educating the household's youngster (CCTS) anel one frec of conditionalities (CTS) - in order to evaluate the impact of these programs on the variables of concern1 Wc fine! that both policies have similar qualitativo rcsults. Quantitatively, howcvcr, the CCTS outperforms its unconclitional version in all fielcls analyzecl, revealing itself to be a preferable policy.
647

A Reservoir of Adaptive Algorithms for Online Learning from Evolving Data Streams

Pesaranghader, Ali 26 September 2018 (has links)
Continuous change and development are essential aspects of evolving environments and applications, including, but not limited to, smart cities, military, medicine, nuclear reactors, self-driving cars, aviation, and aerospace. That is, the fundamental characteristics of such environments may evolve, and so cause dangerous consequences, e.g., putting people lives at stake, if no reaction is adopted. Therefore, learning systems need to apply intelligent algorithms to monitor evolvement in their environments and update themselves effectively. Further, we may experience fluctuations regarding the performance of learning algorithms due to the nature of incoming data as it continuously evolves. That is, the current efficient learning approach may become deprecated after a change in data or environment. Hence, the question 'how to have an efficient learning algorithm over time against evolving data?' has to be addressed. In this thesis, we have made two contributions to settle the challenges described above. In the machine learning literature, the phenomenon of (distributional) change in data is known as concept drift. Concept drift may shift decision boundaries, and cause a decline in accuracy. Learning algorithms, indeed, have to detect concept drift in evolving data streams and replace their predictive models accordingly. To address this challenge, adaptive learners have been devised which may utilize drift detection methods to locate the drift points in dynamic and changing data streams. A drift detection method able to discover the drift points quickly, with the lowest false positive and false negative rates, is preferred. False positive refers to incorrectly alarming for concept drift, and false negative refers to not alarming for concept drift. In this thesis, we introduce three algorithms, called as the Fast Hoeffding Drift Detection Method (FHDDM), the Stacking Fast Hoeffding Drift Detection Method (FHDDMS), and the McDiarmid Drift Detection Methods (MDDMs), for detecting drift points with the minimum delay, false positive, and false negative rates. FHDDM is a sliding window-based algorithm and applies Hoeffding’s inequality (Hoeffding, 1963) to detect concept drift. FHDDM slides its window over the prediction results, which are either 1 (for a correct prediction) or 0 (for a wrong prediction). Meanwhile, it compares the mean of elements inside the window with the maximum mean observed so far; subsequently, a significant difference between the two means, upper-bounded by the Hoeffding inequality, indicates the occurrence of concept drift. The FHDDMS extends the FHDDM algorithm by sliding multiple windows over its entries for a better drift detection regarding the detection delay and false negative rate. In contrast to FHDDM/S, the MDDM variants assign weights to their entries, i.e., higher weights are associated with the most recent entries in the sliding window, for faster detection of concept drift. The rationale is that recent examples reflect the ongoing situation adequately. Then, by putting higher weights on the latest entries, we may detect concept drift quickly. An MDDM algorithm bounds the difference between the weighted mean of elements in the sliding window and the maximum weighted mean seen so far, using McDiarmid’s inequality (McDiarmid, 1989). Eventually, it alarms for concept drift once a significant difference is experienced. We experimentally show that FHDDM/S and MDDMs outperform the state-of-the-art by representing promising results in terms of the adaptation and classification measures. Due to the evolving nature of data streams, the performance of an adaptive learner, which is defined by the classification, adaptation, and resource consumption measures, may fluctuate over time. In fact, a learning algorithm, in the form of a (classifier, detector) pair, may present a significant performance before a concept drift point, but not after. We define this problem by the question 'how can we ensure that an efficient classifier-detector pair is present at any time in an evolving environment?' To answer this, we have developed the Tornado framework which runs various kinds of learning algorithms simultaneously against evolving data streams. Each algorithm incrementally and independently trains a predictive model and updates the statistics of its drift detector. Meanwhile, our framework monitors the (classifier, detector) pairs, and recommends the efficient one, concerning the classification, adaptation, and resource consumption performance, to the user. We further define the holistic CAR measure that integrates the classification, adaptation, and resource consumption measures for evaluating the performance of adaptive learning algorithms. Our experiments confirm that the most efficient algorithm may differ over time because of the developing and evolving nature of data streams.
648

As desigualdades de Bohnenblust-Hille e Hardy-Littlewood

Almeida, Jonathas Phillipe de Jesus 04 April 2016 (has links)
Submitted by ANA KARLA PEREIRA RODRIGUES (anakarla_@hotmail.com) on 2017-08-17T16:04:13Z No. of bitstreams: 1 arquivototal.pdf: 699730 bytes, checksum: d48ddf5357572db4dac922761f91c532 (MD5) / Made available in DSpace on 2017-08-17T16:04:13Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 699730 bytes, checksum: d48ddf5357572db4dac922761f91c532 (MD5) Previous issue date: 2016-04-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In this study we show two classical inequalities, namely Bohnenblust-Hille inequality and Hardy-Littlewood inequality. The rst one, conceived as a tool for the study of problems related to Dirichlet series, is a generalization of Littlewood`s 4/3 inequality to multilinear forms. The second is a generalization of Bohnenblust-Hille inequality, produced by the replacement of c0 with lp. / No presente trabalho abordaremos duas desigualdades cl assicas, a saber, a Desigualdade de Bohnenblust-Hille e a Desigualdade de Hardy- Littlewood. A primeira, surgiu como ferramenta para o estudo de problemas relacionados a s eries de Dirichlet e e uma generaliza c~ao para formas multilineares da Desigualdade 4/3 de Littlewood. A segunda consiste de uma generaliza c~ao da Desigualdade de Bohnenblust-Hille, produzida pela substituição de c0 por lp.
649

Desigualdade de Adams em domínios ilimitados / Adams inequality in unbounded domains

Rocha, Fábio Sodré 10 August 2018 (has links)
Submitted by Liliane Ferreira (ljuvencia30@gmail.com) on 2018-09-05T10:48:04Z No. of bitstreams: 2 Dissertação - Fábio Sodré Rocha - 2018.pdf: 2598970 bytes, checksum: 6dcbeb213d900d41e0a2064ff8a20d22 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-09-05T11:22:03Z (GMT) No. of bitstreams: 2 Dissertação - Fábio Sodré Rocha - 2018.pdf: 2598970 bytes, checksum: 6dcbeb213d900d41e0a2064ff8a20d22 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-09-05T11:22:03Z (GMT). No. of bitstreams: 2 Dissertação - Fábio Sodré Rocha - 2018.pdf: 2598970 bytes, checksum: 6dcbeb213d900d41e0a2064ff8a20d22 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-08-10 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / In this work our aim is to present an extension of the Trudinger-Moser inequality [20] in unbounded domains of Rn for Sobolev Spaces involving high order derivatives. This inequality is nowadays known as Adams-type inequality [1]. We study the techniques developed in the works due to F. Sani and B. Ruf in [23] and due to N. Lam and G. Lu in [16] which are, essentially, combinations of the Comparison Principle of Trombetti and Vazquez for polyharmonic operators and a symmetrization argument, also known as Schwarz Symmetrization. "With such techniques in hands", our aim is to reduce our problem to the radial case and, as a consequence, find an upper bound for the supremum over all functions belonging to the unit ball of Wn;mn (Rn) provided with some specific norm, as well as the sharpness of the constant that appears in Adams inequalities. / Neste trabalho temos como objetivo apresentar uma extensão da desigualdade de AdamsTrudinger-Moser [1] em domínios ilimitados de Rn para espaços de Sobolev envolvendo derivadas de ordem superior no caso crítico. Esta desigualdade é conhecida hoje como desigualdade do tipo Adams [1]. Nosso estudo é baseado nas técnicas desenvolvidas nos trabalhos devidos à F. Sani e B. Ruf em [23] e à N. Lam e G. Lu em [16], que são, essencialmente, combinações do Princípio de Comparação de Vazquez-Trombetti para operadores poliharmônicos e um argumento de simetrização, também conhecido como Simetrização de Schwarz. Munidos de tais técnicas, nosso objetivo é reduzir nosso problema ao caso radial, e como consequência, encontrar um limite superior para o supremo sobre todas as funções pertecentes à bola unitária de Wn;mn (Rn) provido de uma norma específica, bem como também mostrar a otimalidade da constante presente na desigualdade do tipo Adams.
650

Elasticities income inequality and poverty in northeast states: an analysis of the period from 1981 to 2009 / Elasticidades renda e desigualdade da pobreza dos estados no nordeste: uma anÃlise do perÃodo de 1981 a 2009

Geraldo Feitosa Lima Filho 18 June 2012 (has links)
nÃo hà / The objective of this study is to estimate and analyze the income elasticity of poverty and inequality in the Brazilian Northeast. For this, we used the Headcount (Po), the proportion of indigents, the Gini Index and Average per capita Income for the period 1981 to 2009. Regarding the methodology used to measure the elasticity, we chose to econometric techniques for panel data, given that information was used for the nine Northeast states in that period. The results showed that policies to reduce income inequality in the Northeast impacts on poverty reduction, in addition, the reduction of inequality has more impact in the fall in poverty levels than just the growth in average income. / O objetivo deste estudo à estimar e analisar as elasticidades renda e desigualdade da renda da pobreza no Nordeste brasileiro. Para isso, foram utilizados a ProporÃÃo de Pobres (Po), a ProporÃÃo de Indigentes, o Ãndice de Gini e a Renda mÃdia per capita, para o perÃodo de 1981 a 2009. No tocante à metodologia empregada para aferir as elasticidades, optou-se por tÃcnicas economÃtricas para dados em painel, haja vista que foram utilizadas informaÃÃes para os nove estados da RegiÃo Nordeste no referido perÃodo. Os resultados mostraram que as polÃticas destinadas a reduzir a desigualdade de renda na RegiÃo Nordeste impactam na reduÃÃo da pobreza. AlÃm disso, a reduÃÃo desta desigualdade tem mais impacto na queda dos nÃveis de pobreza do que simplesmente o crescimento da renda mÃdia.

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