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CEO Characteristics and Firm Performance / Caractéristiques des dirigeants et performances des entreprisesTibbetts Bollaert, Helen 05 September 2011 (has links)
Dans les trois chapitres de cette thèse nous explorons le lien entre les performances des entreprises et les caractéristiques psychologiques des dirigeants. Dans un premier chapitre conceptuel, nous étudions les fondements théoriques des travaux en finance comportementale d'entreprise en analysant l'hubris et les concepts qui lui sont apparentés. Nous suggérons des pistes de recherche futures qui, pour certaines, sont mises en oeuvre dans les deux autres chapitres de ce travail. Dans le second chapitre, nous étudions l'impact du narcissisme des dirigeants acquéreurs et cibles sur les aspects privés d'un échantillon de fusions-acquisitions américaines. Nos résultats indiquent que desniveaux de narcissisme plus élevés chez les dirigeants acquéreurs sont associés à une plus forte probabilité que l'acquéreur initie l'opération et à une période plus courte entre l'initiation de l'opération et son annonce publique. Nos résultats suggèrent également que des niveaux de narcissisme plus élevés chez les dirigeants cibles sont positivement associés à la prime offerte et négativement associés aux rendements anormaux cumulés de l'acquéreur. Dans le troisième chapitre, nous analysons l'effet du leadership authentique du dirigeant sur les performances boursières etd'exploitation d'un échantillon d'entreprises du SBF 250. Nous collectons des données sur le leadership authentique par le biais de questionnaires. Nous analysons la différence entre les performances des entreprises en les affectant à trois portefeuilles selon le niveau de leadership authentique en utilisant l'analyse en trois facteurs de Fama et French. Nous ne trouvons aucun lien significatif entre le niveau de leadership authentique du dirigeant et la performance boursière. Dansles analyses des performances d'exploitation, nous trouvons un lien positif et significatif entre le niveau de leadership authentique et la rentabilité économique (ROA). / We study the effect of CEO psychological characteristics on firm performance in three papers. We first consider the theoretical background to work in behavioral corporate finance in a conceptual paper analyzing hubris and related psychological concepts. In this paper we put forward ideas for future research, some of which we implement subsequent papers. In paper 2, we study the effect of acquirer and target CEO narcissism on the private aspects of the takeover process in a sample of US M&A deals. We find that higher levels of acquirer CEO narcissism are associated with a higher probability of deal initiation by the acquirer and with a shorter length of time between deal initiation and announcement. Concerning value effects, our results suggest that higher levels of target CEO narcissism are positively related to bid premium and negatively related to acquirer cumulative abnormal returns. In addition, the difference between acquirer and target CEO narcissism is a significant factor in explaining the different aspects of the takeover process. In the third paper, we analyze the effect of CEO authentic leadership on the market and operating performance of a sample of listed French firms. We collect data on CEO authentic leadership using questionnaires. We analyze the difference in performance of firms sorted into three portfolios according to the level of CEO authentic leadership using a Fama French three factor analysis. We fail to find a significant relationship between CEO authentic leadership and market performance. In the operating performance analyses, we find a positive association between CEO authentic leadership and ROA.
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A Static Slicing Tool for Sequential Java ProgramsDevaraj, Arvind January 2007 (has links) (PDF)
A program slice consists of a subset of the statements of a program that can potentially affect values computed at some point of interest. Such a point of interest along with a set of variables is called a slicing criterion. Slicing tools are useful for several applications, such as program understanding, testing, program integration, and so forth. Slicing object oriented programs has some special problems that need to be addressed due to features like inheritance, polymorphism and dynamic binding. Alias analysis is important for precision of slices. In this thesis we implement a slicing tool for sequential Java programs in the Soot framework. Soot is a front-end for Java developed at McGill University and it provides several forms of intermediate code. We have integrated the slicer into the framework. We also propose an improved technique for intraprocedural points-to analysis. We have implemented this technique and compare the results of the analysis with those for a flow-insensitive scheme in Soot. Performance results of the slicer are reported for several benchmarks.
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A Dynamic Workflow Framework for Mass Customization Using Web Service and Autonomous Agent TechnologiesKarpowitz, Daniel J. 07 December 2006 (has links)
Custom software development and maintenance is one of the key expenses associated with developing automated systems for mass customization. This paper presents a method for reducing the risk associated with this expense by developing a flexible environment for determining and executing dynamic workflow paths. Strategies for developing an autonomous agent-based framework and for identifying and creating web services for specific process tasks are presented. The proposed methods are outlined in two different case studies to illustrate the approach for both a generic process with complex workflow paths and a more specific sequential engineering process.
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Validation of the Enhanced Integrated Climatic Model (EICM) for the Ohio SHRP Test Road at U.S. 23Quintero, Natalia M. January 2007 (has links)
No description available.
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Processamento Inteligente de Sinais de Press?o e Temperatura Adquiridos Atrav?s de Sensores Permanentes em Po?os de Petr?leoPires, Paulo Roberto da Motta 06 February 2012 (has links)
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Previous issue date: 2012-02-06 / Originally aimed at operational objectives, the continuous measurement of well bottomhole pressure and temperature, recorded by permanent downhole gauges (PDG), finds
vast applicability in reservoir management. It contributes for the monitoring of well performance and makes it possible to estimate reservoir parameters on the long term. However, notwithstanding its unquestionable value, data from PDG is characterized by a large
noise content. Moreover, the presence of outliers within valid signal measurements seems to be a major problem as well. In this work, the initial treatment of PDG signals is addressed, based on curve smoothing, self-organizing maps and the discrete wavelet transform.
Additionally, a system based on the coupling of fuzzy clustering with feed-forward neural networks is proposed for transient detection. The obtained results were considered quite
satisfactory for offshore wells and matched real requisites for utilization / Originalmente voltadas ao monitoramento da opera??o, as medi??es cont?nuas de press?o e temperatura no fundo de po?o, realizadas atrav?s de PDGs (do ingl?s, Permanent Downhole Gauges), encontram vasta aplicabilidade no gerenciamento de reservat?rios. Para tanto, permitem o monitoramento do desempenho de po?os e a estimativa de par?metros de reservat?rios no longo prazo. Contudo, a despeito de sua inquestion?vel utilidade, os dados adquiridos de PDG apresentam grande conte?do de ru?do. Outro aspecto igualmente desfavor?vel reside na ocorr?ncia de valores esp?rios (outliers) imersos entre as medidas registradas pelo PDG. O presente trabalho aborda o tratamento inicial de sinais de press?o e temperatura, mediante t?cnicas de suaviza??o, mapas auto-organiz?veis e transformada wavelet discreta. Ademais, prop?e-se um sistema de detec??o de transientes relevantes para an?lise no longo hist?rico de registros, baseado no acoplamento entre clusteriza??o fuzzy e redes neurais feed-forward. Os resultados alcan?ados mostraram-se de todo satisfat?rios para po?os marinhos, atendendo a requisitos reais de utiliza??o dos
sinais registrados por PDGs
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Macroscopic diffusion models for precipitation in crystalline gallium arsenideKimmerle, Sven-Joachim 23 December 2009 (has links)
Ausgehend von einem thermodynamisch konsistenten Modell von Dreyer und Duderstadt für Tropfenbildung in Galliumarsenid-Kristallen, das Oberflächenspannung und Spannungen im Kristall berücksichtigt, stellen wir zwei mathematische Modelle zur Evolution der Größe flüssiger Tropfen in Kristallen auf. Das erste Modell behandelt das Regime diffusionskontrollierter Interface-Bewegung, während das zweite Modell das Regime Interface-kontrollierter Bewegung des Interface behandelt. Unsere Modellierung berücksichtigt die Erhaltung von Masse und Substanz. Diese Modelle verallgemeinern das wohlbekannte Mullins-Sekerka-Modell für die Ostwald-Reifung. Wir konzentrieren uns auf arsenreiche kugelförmige Tropfen in einem Galliumarsenid-Kristall. Tropfen können mit der Zeit schrumpfen bzw. wachsen, die Tropfenmittelpunkte sind jedoch fixiert. Die Flüssigkeit wird als homogen im Raum angenommen. Aufgrund verschiedener Skalen für typische Distanzen zwischen Tropfen und typischen Radien der flüssigen Tropfen können wir formal so genannte Mean-Field-Modelle herleiten. Für ein Modell im diffusionskontrollierten Regime beweisen wir den Grenzübergang mit Homogenisierungstechniken unter plausiblen Annahmen. Diese Mean-Field-Modelle verallgemeinern das Lifshitz-Slyozov-Wagner-Modell, welches rigoros aus dem Mullins-Sekerka-Modell hergeleitet werden kann, siehe Niethammer et al., und gut verstanden ist. Mean-Field-Modelle beschreiben die wichtigsten Eigenschaften unseres Systems und sind gut für Numerik und für weitere Analysis geeignet. Wir bestimmen mögliche Gleichgewichte und diskutieren deren Stabilität. Numerische Resultate legen nahe, wann welches der beiden Regimes gut zur experimentellen Situation passen könnte. / Based on a thermodynamically consistent model for precipitation in gallium arsenide crystals including surface tension and bulk stresses by Dreyer and Duderstadt, we propose two different mathematical models to describe the size evolution of liquid droplets in a crystalline solid. The first model treats the diffusion-controlled regime of interface motion, while the second model is concerned with the interface-controlled regime of interface motion. Our models take care of conservation of mass and substance. These models generalise the well-known Mullins-Sekerka model for Ostwald ripening. We concentrate on arsenic-rich liquid spherical droplets in a gallium arsenide crystal. Droplets can shrink or grow with time but the centres of droplets remain fixed. The liquid is assumed to be homogeneous in space. Due to different scales for typical distances between droplets and typical radii of liquid droplets we can derive formally so-called mean field models. For a model in the diffusion-controlled regime we prove this limit by homogenisation techniques under plausible assumptions. These mean field models generalise the Lifshitz-Slyozov-Wagner model, which can be derived from the Mullins-Sekerka model rigorously, see Niethammer et al., and is well-understood. Mean field models capture the main properties of our system and are well adapted for numerics and further analysis. We determine possible equilibria and discuss their stability. Numerical evidence suggests in which case which one of the two regimes might be appropriate to the experimental situation.
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Performance Evaluation of Foamed Warm Mix Asphalt Produced by Water InjectionAli, Ayman W. 12 August 2013 (has links)
No description available.
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Non-Smooth Optimization by Abs-Linearization in Reflexive Function SpacesWeiß, Olga 11 March 2022 (has links)
Nichtglatte Optimierungsprobleme in reflexiven Banachräumen treten in vielen Anwendungen auf. Häufig wird angenommen, dass alle vorkommenden Nichtdifferenzierbarkeiten durch Lipschitz-stetige Operatoren wie abs, min und max gegeben sind. Bei solchen Problemen kann es sich zum Beispiel um optimale Steuerungsprobleme mit möglicherweise nicht glatten Zielfunktionen handeln, welche durch partielle Differentialgleichungen (PDG) eingeschränkt sind, die ebenfalls nicht glatte Terme enthalten können.
Eine effiziente und robuste Lösung erfordert eine Kombination numerischer Simulationen und spezifischer Optimierungsalgorithmen.
Lokal Lipschitz-stetige, nichtglatte Nemytzkii-Operatoren, welche direkt in der Problemformulierung auftreten, spielen eine wesentliche Rolle in der Untersuchung der zugrundeliegenden Optimierungsprobleme.
In dieser Dissertation werden zwei spezifische Methoden und Algorithmen zur Lösung solcher nichtglatter Optimierungsprobleme in reflexiven Banachräumen vorgestellt und diskutiert.
Als erste Lösungsmethode wird in dieser Dissertation die Minimierung von nichtglatten Operatoren in reflexiven Banachräumen mittels sukzessiver quadratischer Überschätzung vorgestellt, SALMIN.
Ein neuartiger Optimierungsansatz für Optimierungsprobleme mit nichtglatten elliptischen PDG-Beschränkungen, welcher auf expliziter Strukturausnutzung beruht, stellt die zweite Lösungsmethode dar, SCALi.
Das zentrale Merkmal dieser Methoden ist ein geeigneter Umgang mit Nichtglattheiten. Besonderes Augenmerk liegt dabei auf der zugrundeliegenden nichtglatten Struktur des Problems und der effektiven Ausnutzung dieser, um das Optimierungsproblem auf angemessene und effiziente Weise zu lösen. / Non-smooth optimization problems in reflexive Banach spaces arise in many applications. Frequently, all non-differentiabilities involved are assumed to be given by Lipschitz-continuous operators such as abs, min and max. For example, such problems can refer to optimal control problems with possibly non-smooth objective functionals constrained by partial differential equations (PDEs) which can also include non-smooth terms. Their efficient as well as robust solution requires numerical simulations combined with specific optimization algorithms.
Locally Lipschitz-continuous non-smooth non-linearities described by appropriate Nemytzkii operators which arise directly in the problem formulation play an essential role in the study of the underlying optimization problems.
In this dissertation, two specific solution methods and algorithms to solve such non-smooth optimization problems in reflexive Banach spaces are proposed and discussed.
The minimization of non-smooth operators in reflexive Banach spaces by means of successive quadratic overestimation is presented as the first solution method, SALMIN.
A novel structure exploiting optimization approach for optimization problems with non-smooth elliptic PDE constraints constitutes the second solution method, SCALi.
The central feature of these methods is the appropriate handling of non-differentiabilities. Special focus lies on the underlying structure of the problem stemming from the non-smoothness and how it can be effectively exploited to solve the optimization problem in an appropriate and efficient way.
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