Dissertations / Theses on the topic 'Macross'

De senaste 20 åren har Europa genomgått flera kriser som har bidragit till splittringar stater emellan. Parallellt med att allt fler nationalistiska och populistiska partier med viljan att lämna EU växer fram i Europa sprider Frankrikes president Emmanuel Macron EU-vänlig information på sociala medier där han propagerar för sina, Frankrikes och EU:s framtidsvisioner. Genom att studera hur europeiska ledare uttalar sig om EU kan vi få en bild av i vilken riktning de vill driva EU-samarbetet. Uppsatsen syftar till att klarlägga vilka värden som Macrons politiska retorik representerar genom att kategorisera hans uttalanden utifrån tidigare forskning om statliga eliters visioner om EU. Resultatet visar att Macrons vision om EU är att unionen ska fungera som en värdebaserad gemenskap där solidaritet och en gemensam EU-identitet är centrala utgångspunkter. Han har även en vision om att EU ska komma att växa till en allt större strategisk global aktör.

With the prevalence of legacy C/C++ code, issues of readability and maintainability have become increasingly important. When we consider the problem of refactoring or migrating C/C++ code, we see the significant role that preprocessor directives play. It is partially because of these preprocessor directives that code maintenance has become extremely difficult. This thesis describes a method of fact extraction and code manipulation to create a set of transformations which will remove preprocessor directives from the original source, converting them into regular C/C++ code with as few changes as possible, while maintaining readability in the code. In addition, some of the subtle issues that may arise when migrating preprocessor directives are explored. After discussing the general architecture of the test implementation, an examination of some metrics gathered by running it on two software systems is given.

ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada
This paper introduces a set of macros that automate the importing of antenna data into Excel and charting that data. These macros (as discussed here) import data from a ViaSat ACUs (Antenna Control Unit) and a TCS ACU (Telemetry & Communications Systems Inc). After the import is complete, the macros can build a set of charts, all formatted and labeled in a predetermined and standard manner. A task that may take half a day or more can be completed in minutes. The concept and layout of the macros lend them to quick adaptation to your data. In scenarios of “test and collect” followed by “import and chart”, the data can be imported and charted within the minute.

Texte remanié de: Th. doct.--Lettres classiques--Paris--EPHE, 1999. Titre de soutenance : La survie des "Commentarii in Somnium Scipionis" de Macrobe, étude et édition des "Glosae colonienses super Macrobium.
En appendice, choix de documents. Bibliogr. p. 299-325. Index.

Abstração é um processo que consiste em encontrar similaridades em artefatos e omitir detalhes desnecessários em um particular momento. Em geral, tal processo resulta em simplificação, substituindo situações do mundo real complexas e excessivamente detalhadas por modelos compreensíveis que admitem resolução. Na computação, existem estilos de programação que fornecem ao programador uma visão particular sobre a organização e execução de um programa. Cada estilo viabiliza formas de representação e tratamento de abstrações aderentes ao conjunto de conceitos, valores, percepções e práticas compartilhadas por uma comunidade. Em particular, o fenômeno de reescrita de termos viabiliza transformações entre espaços de abstração. Como instância de tal fenômeno, macros constituem um padrão sintático que especifica uma transformação simbólica ou algorítmica sobre uma sequência de símbolos associada. Na ocorrência de uma instância de tal padrão sintático, este é substituído pela aplicação de sua transformação correspondente. Dada a importância da disponibilização de estruturas de representação mais convenientes às necessidades dos usuários, o objetivo principal desta tese é tratar da utilização de sistemas de reescrita como mecanismos de abstração em transformações textuais. Para tal, técnicas de projeto e aspectos de implementação de tais sistemas são apresentados, com enfoque em macros.
Abstraction is a process of finding similarities in artifacts and omitting unnecessary details at a particular moment. In general, such a process results in simplification, replacing complex and overly detailed real-world situations with understandable models that admit resolution. In computing, there are programming styles that give the programmer a particular insight into the organization and execution of a program. Each style enables forms of representation and treatment of abstractions adhering to the set of concepts, values, perceptions and practices shared by a community. In particular, the term rewriting phenomenon enables transformations along spaces of abstraction. As an instance of such a phenomenon, macros constitute a syntactic pattern that specifies a symbolic or algorithmic transformation over an associated symbol sequence. In the occurrence of an instance, the matched syntactic pattern is replaced by the application of its corresponding transformation. Given the importance of making representation structures more convenient to users\' needs, this thesis aims at addressing the use of rewriting systems as abstraction mechanics in textual transformations. To this end, design techniques and implementation aspects of such systems are presented, focusing on macros.

FPGA design implementation and debug tools have not kept pace with the advances in FPGA device density. The emphasis on area optimization and circuit speed has resulted in longer runtimes of the implementation tools. We address the implementation problem using a divide-and-conquer approach in which some device area and circuit speed is sacrificed for improved implementation turnaround time. The PATIS floorplanner enables dynamic modular design that accelerates implementation for incremental changes to a design. While the existing implementation flows facilitate timing closure late in the design cycle by reusing the layout of unmodified blocks, dynamic modular design accelerates implementation by achieving timing closure for each block independently. A complete re-implementation is still rapid as the design blocks can be processed by independent and concurrent invocations of the standard tools. PATIS creates the floorplan for implementing modules in the design. Bus macros serve as module interfaces and enable independent implementation of the modules. The dynamic modular design flow achieves around 10x speedup over the standard design flow for our benchmark designs.
Master of Science

Field programmable gate arrays (FPGAs) offer an attractive compute platform because of their highly parallel and customizable nature in addition to the potential of being reconfigurable to any almost any desired circuit. However, compilation time (the time it takes to convert user design input into a functional implementation on the FPGA) has been a growing problem and is stifling designer productivity. This dissertation presents a new approach to FPGA compilation that more closely follows the software compilation model than that of the application specific integrated circuit (ASIC). Instead of re-compiling every module in the design for each invocation of the compilation flow, the use of pre-compiled modules that can be "linked" in the final stage of compilation are used. These pre-compiled modules are called hard macros and contain the necessary physical information to ultimately implement a module or building block of a design. By assembling hard macros together, a complete and fully functional implementation can be created within seconds. This dissertation describes the process of creating a rapid compilation flow based on hard macros for Xilinx FPGAs. First, RapidSmith, an open source framework that enabled the creation of custom CAD tools for this work is presented. Second, HMFlow, the hard macro-based rapid compilation flow is described and presented as tuned to compile Xilinx FPGA designs as fast as possible. Finally, several modifications to HMFlow are made such that it produces circuits with clock rates that run at more than 75% of Xilinx-produced implementations while compiling more than 30X faster than the Xilinx tools.

Macraes Gold Mine at Macraes Flat is located approximately 60km north-west of Dunedin, and is currently the largest producer of gold in New Zealand. Open-pit mining currently takes place in the three large pits of Round Hill, Southern and Innes Mills along the Hyde-Macraes Shear Zone (HMSZ) which is the source of gold mineralisation. This study is an engineering geological investigation into pit slope stability at Macraes. Pit slope stability is an integral part of open-pit mining since slopes should be as steep as possible to minimise waste material which needs to be removed, yet shallow enough to minimise potential hazards to personnel and equipment below pit slopes. Joints at Macraes are characterised by high friction angles (45-55°) as a result of roughness/waviness along the joint surface at low normal stresses. Geotechnical testing of fault gouge, and back analysis of fault controlled failures, shows much lower shear strengths for faults (c=0 kPa, Ø =6-14°) than those previously assumed for the mine (c.f. c=10-14 kPa, Ø=15-17°), with the small discrepancies (≈8°) between laboratory test results (5°) and back analysis results (13°) being attributed to both the removal of coarser material from laboratory samples and surface roughness/waviness, which would otherwise increase the friction. X-ray diffraction analysis shows a dominance of interlayered swelling chlorite/smectite in clay fraction of fault gouge which will heave when water is present increasing the instability of pit slopes. Intact rock strength testing on schist from the mine shows much lower strengths (4.8 - 61.2 MPa) for the material than previously determined at other project locations in Otago (c.f. 29 - 86MPa). Pelitic schist at the mine appears to be stronger than psammitic schist which was unexpected and contrasts with previous testing in Otago. The higher strengths of pelitic schist may reflect annealing processes associated with mineralisation of the HMSZ, but has not been fully investigated. Two structural domains can be recognised at the mine which are controlled by the Hanging Wall Shear (HWS) of the HMSZ. The rock mass above the HWS is dominantly psammitic and is referred to as the Hanging Wall Zone Domain (HWZD), while the rock mass below the HWS is dominantly pelitic and referred to as the Ore Zone Domain (OZD). Three joint sets and five fault sets are recognised in the HWZD, while in the OZD the same three joint sets as for the HWZD are recognised, but only four of the fault sets are present. A standard recording sheet for pit slope failures is developed to assist engineering geological investigations by recording the relevant information in a consistent format. Such a sheet forms the basis for a pit slope failure database, ensures consistency in recording and provides records of failure for assessments of failure development with time. Failures at Macraes are classified according to the geometry of the failure surface and the types of discontinuities controlling failure as: high angle planar, low angle block, toppling, joint-joint wedge, joint-fault wedge, and fault-fault wedge. High groundwater pressures, and lower shear strength material than previously assumed, are interpreted as major factors in driving pit slope failures at Macraes, and horizontal drainage is recommended as the most effective method in preventing future pit slope failures. Two large pit slope failures, RH27 (volume = 900m³) & RH28 (volume = 450 000m³), located on the north wall of Round Hill Pit occurring prior to this project, are mapped in detail at scales of 1:500 and 1:800 with failure mechanisms interpreted. RH27 is a complex wedge failure formed between the Slip 27 fault and a westerly dipping joint set. RH28 is a large wedge failure formed between two faults plunging at low angles (≈3°) out of the pit slope and driven by high water pressures along a fault set parallel to the pit slope. The stability of RH27 and RH28 is determined, and future development and implications to mining operations assessed. Thirteen types of failure are predicted to occur at Macraes based upon the integration of hydrological influences, strength properties, rock mass structure, and calibration with those failures observed at Macraes to date. Kinematic models for these thirteen failure models have been constructed to assist in recognition of these predicted failure modes in the field. Prediction of pit slope failures should be based on sound monitoring and management of recognised active failures, and should include: visual inspections and photography, movement monitoring, hydrologic monitoring and warning monitoring, so that the hazards and adverse effects associated with unexpected slope failure movements are minimised.

Thesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2017.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 77-78).
In this thesis, we present the design and implementation of a new novice-oriented programming language with automatically hygienic runtime macros, as well as an interpreter framework for creating such languages. The language is intended to be used as a pedagogical tool for introducing basic programming concepts to introductory programming students. We designed it to have a simple notional machine and to be similar to other modern languages in order to ease a student's transition into other programming languages.
by Jeremy Daniel Kaplan.
M. Eng.

Programmers want to write modular programs to increase maintainability and create abstractions, but modularity hampers optimizations, especially when modules are compiled separately or written in different languages. In languages with syntactic extension capabilities, each module in a program can be written in a separate language, and the module system must ensure that the modules interoperate correctly. In Racket, the module system ensures this by separating module code into phases for runtime and compile-time and allowing phased imports and exports inside modules. We present an algorithm, called demodularization, that combines all executable code from a phased modular program into a single module that can then be optimized as a whole program. The demodularized programs have the same behavior as their modular counterparts but are easier to optimize. We show that programs maintain their meaning through an operational semantics of the demodularization process and verify that performance increases by comparing modular Racket programs to the equivalent demodularized and optimized programs. We use the existing Racket optimizer to optimize the demodularized programs by decompiling them into an intermediate form that the optimizer uses. We also demonstrate a dead code elimination optimization that dramatically reduces the file size of demodularized Racket programs.

Macro systems allow programmers abstractions over the syntax of a programming language. This gives the programmer some of the same power posessed by a programming language designer, namely, the ability to extend the programming language to meet the needs of the programmer. The value of such systems has been demonstrated by their continued adoption in more languages and platforms. However, several barriers to widespread adoption of macro systems still exist. The language Racket defines a small core of primitive language constructs, including a powerful macro system, upon which all other features are built. Because of this design, many features of other programming languages can be implemented through libraries, keeping the core language simple without sacrificing power or flexibility. However, slow macro expansion remains a lingering problem in the language's primary implementation, and in fact macro expansion currently dominates compile times for Racket modules and programs. Besides the typical problems associated with slow compile times, such as slower testing feedback, increased mental disruption during the programming process, and unscalable build times for large projects, slow macro expansion carries its own unique problems, such as poorer performance for IDEs and other software analysis tools. In order to improve macro expansion times for Racket, we implement an existing expansion algorithm for R5RS Scheme macros, which comprise a subset of Racket's macro system, and use that implementation to explore optimization opportunities. Our resulting expander appears to be the fastest implementation of a R5RS macro expander in a high-level language and performs several times faster than the existing C-based Racket implementation.

"November 2001".
Thesis (PhD)--Macquarie University, Division of Environmental and Life Sciences, Department of Biological Sciences, 2002.
Bibliography: leaves 136-157.
General introduction -- Molecular markers for comparative and quantitative studies in macropods -- Genetic linkage map construction in the tammar wallaby (M. eugenii) -- Intraspecific variation, sex-biased dispersal and phylogeography of the eastern grey kangaroo (M. giganteus) -- General discussion.
The analysis of DNA using molecular techniques is an important tool for studies of evolutionary relationships, population genetics and genome organisation. The use of molecular markers within marsupials is primarily limited by their availability and success of amplification. Within this study, 77 macropodid type II microsatellite loci and two type I genetic markers were characterised within M. eugenii to evaluate polymorphic levels and cross-species amplification artifacts. Results indicated that 65 microsatellite loci amplified a single locus in M. eugenii with 44 exhibiting high levels of variability. The success of crossspecies amplification of microsatellite loci was inversely proportional to the evolutionary distance between the macropod species. It is revealed that the majority of species within the Macropodidae are capable of using many of the available heterologous microsatellites. When comparing the degree of variability between source-species and M. eugenii, most were significantly higher within source species (P < 0.05). These differences were most likely caused by ascertainment bias in microsatellite selection for both length and purity. -- The production of a marsupial genetic linkage map is perhaps one of the most important objectives in marsupial research. This study used a total of 353 informative meioses and 64 genetic markers to construct a framework genetic linkage map for M. eugenii. Nearly all markers (93.7%) formed a significant linkage (LOD > 3.0) with at least one other marker. More than 70% (828 cM) of the genome had been mapped when compared with chiasmata data. Nine linkage groups were identified, with all but one (LG7; X-linked) allocated to the autosomes. Theses groups ranged in size from 15.7 cM to 176.5 cM, and have an average distance of 16.2 cM between adjacent markers. Of the autosomal linkage groups, LG2 and LG3 were assigned to chromosome 1 and LG4 localised to chromosome 3 based on physical localisation of genes. Significant sex-specific distortions towards reduced female recombination rates were revealed in 22% of comparisons. Positive interference was observed within all the linkage groups analysed. When comparing the X-chromosome data to closely related species it is apparent that it is conserved both in synteny and gene order. -- The investigation of population dynamics of eastern grey kangaroos has been limited to a few ecological studies. The present investigation provides analysis of mtDNA and microsatellite data to infer both historical and contemporary patterns of population structuring and dispersal. The average level of genetic variation across sample locations was exceedingly high (h = 0.95, HE = 0.82), and is one of the highest observed for marsupials. Contrary to ecological studies, both genic and genotypic analyses reveal weak genetic structure of populations where high levels of dispersal may be inferred up to 230 km. The movement of individuals was predominantly male-biased (average N,m = 22.61, average N p = 2.73). However, neither sex showed significant isolation by distance. On a continental scale, there was strong genetic differentiation and phylogeographic distinction between southern (TAS, VIC and NSW) and northern (QLD) Australian populations, indicating a current and / or historical restriction of geneflow. In addition, it is evident that northern populations are historically more recent, and were derived from a small number of southern eastern grey kangaroo founders. Phylogenetic comparisons between M. g. giganteus and M. g. tasmaniensis, indicated that the current taxonomic status of these subspecies should be revised as there was a lack of genetic differentiation between the populations sampled.
Mode of access: World Wide Web.
xv, 182 leaves ill

Ce travail est dédié à la prise en compte d'une compressibilité plastique induite par l'endommagement ductile dans les matériaux métalliques pour des applications en simulation des procédés de mise en forme. Dans le cadre de la mécanique de l'endommagement continu (MEC), nous généralisons deux modèles existants afin d'y introduire une variation de volumique induite par l'endommagement. Le premier modèle, de nature macroscopique, utilise deux variables d'endommagement, dont une gouvernée par le comportement hydrostatique. Le deuxième de nature micro-macro introduit un critère d'écoulement endommageable à l'échelle des systèmes de glissement cristallin (plasticité cristalline). Ce critère combine les effets de la contrainte de cisaillement et de la contrainte normale pour tenir compte de la variation de volume induite.
Ces deux modèles ont été implémentés dans le code Zébulon avec un schéma d'intégration local implicite (prédiction élastique retour radial) et explicite (Runge-Kutta).
La validation de ces modèles a été réalisée avec des simulations numériques par la MEF sur des exemples simples (essai de traction) et concernent l'étude des étapes des phénomènes de localisation (diffuse, striction, et modes de rupture finale) en comparaison avec un modèle de type Gurson. Quelques applications de procédés de mise en forme (poinçonnage et emboutissage) ont suivis pour les deux familles de modèles.

If these macro inclusions are not detected before the material is put in used, its mechanical properties are greatly affected and this can lead to outrageous consequences in the engineering application.

Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2000.
Includes bibliographical references (leaves 109-110).
by Ravi A. Nanavati.
M.Eng.

Despite the traditional separation of academic studies regarding macroeconomics and financial markets, recently, there has been increased interest in investigating the relationship between them based on models of the term structure of interest rates. This thesis in “Macro-finance” connects macroeconomic variables and the fixed income financial markets, both Treasury and corporate. Traditional economic models in linking these markets with the macroeconomy concentrate on the determination of the short rate, as the policy instrument, via the familiar Taylor-rule. The essays in this thesis provide evidence of the mutual relationships in two dimensions: a) price formation in these markets and macroeconomic conditions originating from home and abroad, and b) information originating in these markets and expectations regarding the future state of the economy. In the first essay, we study the impact of oil price shocks in the global crude oil market on the dynamics of the entire term structure. The responses of the yield factors to oil market shocks are shown to differ contingent on the underlying sources driving oil price shocks and the country's dependency on oil. The oil supply and demand shocks explain a considerable amount of variations in the term structure of interest rates, especially in countries with high oil dependency. The second essay tests the predictive power of economic policy uncertainty (EPU) for future bond returns. Using the policy uncertainty measure recently developed by Baker et al. (2016), we investigate the relationship between economic uncertainty and excess bond returns. The impact of the uncertainty is shown to be larger for shorter maturities in near investment horizons. An affine term structure model incorporating the uncertainty factor produces higher fluctuations in term premia estimates which display strong countercyclical movements and accords with expectations. Finally, we examine whether professional forecasters incorporate high-frequency information about credit conditions in revising their economic forecasts. Using Mixed Data Sampling regression approach, we find that daily credit spreads have significant predictive ability for monthly forecast revisions of output growth, at both aggregate and individual levels. The relations are shown to be notably strong during ‘bad’ economic conditions, indicating that forecasters anticipate more pronounced effects of credit tightening during economic downturns.

Thesis advisor: Sanjay K. Chugh
Thesis advisor: Fabio Schiantarelli
My doctoral research focuses on the role of labor market frictions in shaping macroeconomic outcomes. I am currently pursuing three main lines of research that constitute the three chapters of this dissertation. The first chapter focuses on involuntary part-time employment as an additional margin used by firms to adjust to business cycle fluctuations. The chapter documents empirical regularities of involuntary part-time employment in the U.S. and furnishes a tractable analytical framework for studying this phenomenon that has gained so much attention in the years that followed the Great Recession. In the second chapter, which is joint work with Sanjay Chugh, Ryan Chahrour and Alan Finkelstein-Shapiro, we study the labor market wedge in the context of a search and matching model to understand how static and dynamic inefficiencies change over the business cycle. Measuring the labor market wedge and understanding its sources of movement is of great importance from a macroeconomic point of view, as existing research shows it holds a prominent place in explaining fluctuations in aggregate output. Finally, in the third chapter I study empirically the determinants of the job finding probability, a key object in the context of frictional labor markets. More specifically, I analyze how decisions on time allocation by the unemployed affect their chances of finding a job, and identify the activities that make more likely for an unemployed individual to receive and accept a job offer. Chapter 1. In recent years researchers and policymakers have shown renewed interest in involuntary part-time employment as a crucial indicator of labor market health. The fact that individuals have part-time jobs even though they would be willing to work more hours is evidence that resources in the economy are not employed at full capacity. This group represents almost 40 percent of total underemployment. Despite its large size and importance to policy-makers, surprisingly little literature addresses the empirical regularities or economic role this margin plays in determining labor market outcomes. In "Underemployment and the Business Cycle" I address several questions regarding involuntary part-time employment. First, how does involuntary part-time employment differ from the standard extensive and intensive margins? Second, what factors influence the choice of firms to use involuntary part-time workers? Third, how might economic policy contribute to the existence of involuntary part-time employment in the economy? And, fourth, have there been any changes over time in the response of involuntary part-time employment to changes in aggregate economic conditions and, if so, what explains them? To describe the empirical regularities of involuntary part-time employment, I use detailed micro-level data from longitudinally-linked monthly files of the Current Population Survey. A novel finding that emerges from the analysis of this dataset is that wages of involuntary part-time workers display higher volatility and lower persistence than those of their full-time counterparts, thus indicating a higher degree of flexibility. In addition, I find that changes in involuntary part-time employment are mostly explained by reallocation of workers from full-time to part-time positions within the firm, which involves more than just a mere reduction in hours worked. I then aggregate the data and compute business cycle statistics. Surprisingly, I find that the behavior of involuntary part-time employment resembles the behavior of unemployment more than the one of full-time employment. In fact, the results indicate that involuntary part-time employment is very volatile and strongly countercyclical. To understand the evidence I find at the micro and macro levels, I build an augmented search and matching model of the labor market featuring full-time and part-time employment, and a production function that combines both types of workers. The decision of whether a worker is full-time or part-time is made entirely by the firm, depending on the realizations of both aggregate and idiosyncratic productivity processes. The model is able to deliver the countercyclicality of involuntary part-time employment found in the data. The key mechanism to obtain this result is the relatively higher flexibility of part-time contracts that makes it more profitable for the firm to reallocate workers from full-time to part-time arrangements during recessions. Based on the model that captures key empirical facts, I conduct policy analysis to evaluate the effect of an increase in the cost of health insurance on involuntary part-time employment. The policy experiment predicts that an increase in the cost of health insurance provided by the firm to its full-time workers, such that their share in average full-time wages goes up by 1 percentage point, leads to an increase of steady state involuntary part-time employment by 10 percent, which nowadays would be equivalent to half a million additional involuntary part-time workers. I find evidence that involuntary part-time employment has become more volatile and persistent in the last 25 years. I study the impact that innovation in workforce management practices, a process that started in the 1990s and that has increased the degree of substitutability between full-time and part-time workers, may have had in changing the response over time of involuntary part-time employment to business cycle fluctuations. Impulse response analysis from the model indicates that an increase in the degree of substitutability makes involuntary part-time employment more sensitive to aggregate productivity shocks. Chapter 2. In "The Labor Wedge: A Search and Matching Perspective" we define and quantify static and dynamic labor market wedges in a search and matching model with endogenous labor force participation. Existing literature has generally centered on Walrasian labor markets in characterizing the inefficiencies, or ``gaps'', between labor demand and labor supply. However, given the conventional view in the profession that the matching process plays an important role in the labor market, the neoclassically-measured labor wedge suffers from a misspecification problem as it ignores the role of long-lasting relationships in explaining the cyclical pattern of the labor wedge. To construct the wedge we use a rigorously defined transformation function of the economy, which contains both the matching technology and the neoclassical production technology. Both technologies are primitives of the economy in the sense that a Social Planner must respect both processes. Given the model-appropriate transformation frontier and the household's static and dynamic marginal rates of substitution, we use data on the labor force participation rate, the employment rate, the vacancy rate, real consumption, real government spending, and real GDP to construct static and dynamic labor wedges. We find that, in a version of the model where all employment relationships turn over every period, the static labor wedge is countercyclical, a result that is consistent with existing literature. Once we consider long-lasting employment relationships, we can measure both static and dynamic wedges separately. We then find that, while the static wedge continues to be countercyclical, the dynamic (or intertemporal) wedge is procyclical. Since the latter is associated with the vacancy-posting decision of the firm, this result suggests that understanding the behavior of labor demand may be crucial to explaining the dynamic wedge. Our focus so far has been on obtaining a quantitative measure of both the static and dynamic wedges, and on analyzing their business cycle properties. Now we are working on extending this framework to provide a micro-founded explanation of the forces that could be driving the cyclical movements of the wedges. Chapter 3. Recent research has found that individuals who become unemployed allocate most of their forgone working hours into leisure rather than increasing the time devoted to job search activities. What is the rationale behind this decision? There are many factors that may affect the job search behavior of the unemployed. However, in this study I focus on a particular channel: the decision on how unemployed individuals allocate their time could be biased towards activities that increase their probability of finding a job. They might find more valuable to increase their social activities rather than looking formally for a job because this enhances their network, which could increase their chances of finding a job, even with less search effort. In "The Time Use Decisions of the Unemployed: A Survival Analysis", I conduct a duration analysis to estimate the effect of different time use allocations on the unemployment hazard rate using time use data from the Survey of Unemployed Workers in New Jersey. Defining "finding a job" as a failure, I estimate a single-spell, discrete-time duration model of unemployment with time-varying covariates using semi-parametric techniques. Given that I work with interval-censored data, I conduct the analysis using discrete time survival analysis techniques. The results indicate that education/training activities have a significant and positive impact on the hazard rate, i.e. they increase the probability that an unemployed worker finds a job, while leisure has the opposite effect. Furthermore, neither job-search nor networking have a significant effect on the hazard rate in the baseline specification. However, this result changes when incorporating into the regression interaction terms of these variables with a dummy that takes the value one if the individual is a long-term unemployed and zero otherwise. In this case, the coefficient associated with networking becomes positive and significant, while the coefficient of the interaction term is negative. This implies that networking has a positive effect on the hazard rate for short unemployment spells, but this effect weakens if the individual has been unemployed for a longer period. On the other hand, even after incorporating the interaction term, job search remains insignificant. These findings shed light on why individuals may not want to devote additional time to formal job search: it does not pay off with a higher likelihood of receiving a job offer, regardless of the length of the unemployment spell. On the other hand, other activities, such as investing in education or networking, are positively related to the probability of finding a job -- at least for short unemployment spells -- and thus it makes more sense for these individuals to devote more time to them

In the first paper of my dissertation I document that industries with low offshoring potential have 7.31% higher stock returns per year compared to industries with high offshoring potential, suggesting that the possibility to offshore affects industry risk. This risk premium is concentrated in manufacturing industries that are exposed to foreign import competition. Put differently, the option to offshore effectively serves as insurance against import competition. A two-country general equilibrium dynamic trade model in which firms have the option to offshore rationalizes the return patterns uncovered in the data: industries with low offshoring potential carry a risk premium that is increasing in foreign import penetration. Within the model, the offshoring channel is economically important and lowers industry risk up to one-third. I find that an increase in trade barriers is associated with a drop in asset prices of model firms. The model thus suggests that the loss in benefits from offshoring outweighs the benefits from lower import competition. Importantly, the model prediction that offshorability is negatively correlated with profit volatility is strongly supported by the data. In the second paper (co-authored with Andrea Tamoni and Alex Hsu) we study the impact of fiscal policy shocks on bond risk premia. Government spending level shocks generate positive covariance between marginal utility and inflation (term structure level effect) making nominal bonds a poor hedge against consumption risk leading to positive inflation risk premia. Volatility shocks to spending have strong slope effect (steepening) on the yield curve, producing positive nominal term premia. For level and volatility shocks to capital income tax, term structure level effects dominate, delivering negative risk premia. Fluctuations in term premia are entirely driven by volatility shocks. Lastly, fiscal shocks are amplified at the zero lower bound. The third paper (co-authored with Andrea Tamoni and Alex Hsu) discusses how risk aversion (RA) affects the macroeconomic response to uncertainty shocks. In the data, heightened level of RA during the 2008 crisis amplified the decline of output and investment by roughly 21% and 16%, respectively, at the trough of the recession. The degree of RA determines the impact of second moment shocks in DSGE models featuring stochastic volatility. Ceteris paribus, higher RA leads to stronger responses of macroeconomic variables to uncertainty shocks, making un certainty shocks as economically significant as level shocks. Conversely, elevated RA can amplify or dampen responses to level shocks depending on whether RA exaggerates or attenuates consumption growth expectations.

In terms of the specific topics covered in the thesis, my research aims to further understanding of risky asset return and volatility behaviour from a macro-finance perspective. In three of the four chapters, the macro drivers of both risky asset returns (the first moment) and volatility (the second moment) are studied and analyzed in detail across different geographies and various time periods. The use of both long sample sets and relevant sub-sample periods allows for a more in-depth assessment of the nature and form of these drivers as well as their influence on risky asset return and volatility dynamics, whilst weakening the impact of any endogeneity bias which the empirical estimation framework used may be subject to. The earliest data used in this research starts from the 18th century. In the first chapter, entitled “Macro Drivers of Equity Market Volatility”, the focus is on the construction and analysis of macro state variables, which are shown to have a strong influence on the behaviour of equity return volatility, especially during periods of severe market upheaval. Chapter two examines the relative abilities of GARCH and Stochastic Volatility Models (SV) to forecast volatility, in a world where the true model can be depicted by an EGARCH(1,2) formulation. Turning to chapter three, the relationship between equity returns and inflation (specifically, if equities are a hedge against inflation) is explored using long-term historical data for the US, the UK, Germany and Japan. Finally, chapter four analytically tackles the question of how various investors' (institutional and retail) asset allocation decisions are dependent on both the formulation of the wealth maximization function and the differentiated nature of information signals. Specifically, this chapter focusses on how asset allocation behaviour of various categories of investors (facing different objective functions) may lead to “herding”.

Cette thèse comprend trois articles en macroéconomie financière. L’approche méthodologique commune aux deux premiers est l’application des modèles d’appariement aux marchés financiers. Le troisième contribue à l’étude des événements rares. Le premier article démontre qu’une contagion financière internationale est susceptible d’émerger malgré un régime de taux de change flexible et une substituabilité entre les actifs financiers nationaux et étrangers, contrairement aux résultats standards sous ces deux conditions. A l’inverse des contractions monétaires traditionnelles, des chocs non-walrasiens de coûts de capitalisation bancaire génèrent une contagion internationale. Le deuxième article étudie le rôle du comportement des banquiers dans le défaut bancaire. Le modèle tient compte de l’hétérogénéité des emprunteurs et incorpore une asymétrie d’information au détriment des détenteurs de capitaux. Un aléa moral survient à la suite d’un choc de productivité : les banquiers tendent à choisir les investissements plus rentables à court terme mais dont le risque est supporté par les investisseurs. Ce mécanisme amplifie le rationnement du crédit dans l’économie et alimente le défaut bancaire. Le troisième article étudie l’impact macroéconomique d’une variation de la probabilité d’un événement rare dans un modèle néo-keynésien. Une hausse de la probabilité suffit notamment à générer une récession sans réelle occurrence du « désastre » et produit, en concurrence monopolistique, des réactions de la consommation et des salaires cohérentes. Nous proposons ainsi un cadre d’analyse des effets dynamiques des événements rares, préalable à l’investigation du rôle de la politique monétaire
This dissertation consists of three essays in financial macroeconomics. The methodological approach common to the first two articles is the application of the search and matching theory to financial markets. The third essay builds on the literature on rare events. In the first article, I develop a tractable two-country model in which financial contagion may arise despite a flexible exchange rate regime and substitutability between home and foreign financial assets, contrary to the open-economy standard results under these two conditions. While monetary contractions imply negative output co-movements, in line with the literature, non-walrasian shocks to banks’ funding costs do generate the contagion. The second essay analyzes the role of bankers’ behavior in bank default. The model accounts for heterogeneity in entrepreneurs’ productivity and information asymmetry at the expense of capital holders. Moral hazard arises following a productivity shock: bankers tend to choose investments that are more profitable in the short-run but whose risk is borne by the financiers. This mechanism magnifies credit rationing in the economy and contributes to bank default. The third article examines the macroeconomic impact of a change in the probability of rare events in a New Keynesian model. A rise in the probability of disaster is sufficient to generate a recession without effective occurrence of the disaster. After accounting for monopolistic competition and price stickiness, the responses of consumption and wages are also reminiscent of distressed times. The article thus provides a framework of the dynamic effects of rare events, particularly suitable for further policy analysis

Ce mémoire traite de la modélisation comportementale d'amplificateurs opérationnels dans la gamme de température [C 25°C, 200°C]. La définition d'un modèle haute température, passe par la défini tian d'un modèle valable à 25°C. Ce macro modèle, bien que basé sur les équations classiques des amplificateurs, est défini à l'aide de macro fonctions indépendantes lui conférant une grande modularité et son originalité. On dispose ainsi d'un modèle que l'on peut personnaliser facilement en fonction des applications. On obtient alors un compromis sur la précision et la temps de calcul dont les performances améliorent celles des modèles existants. L'étude des variations des principales caractéristiques d'amplificateurs a montré qu'il était possible de lisser leurs variations an fonction de la température par des polynômes. L'implémentation de ces variations dans le modèle est réalisée à l'aide de paramètres variables polynômialement en fonction de la température; l'utilisation de ces fonctions dégrade très peu le temps de calcul. La précision simulation-expérience, deux fois moins bonne que celle du modèle à température constante, reste cependant suffisamment bonne pour permettre une utilisation du modèle dans la simulation de circuits analogiques dans la gamme de température [25°C, 200°C]. Cette approche de modélisation utilisant des équations simples et un lissage polynômial des caractéristiques permet d'envisager le passage du modèle, testé sur Spice sous forme de schémas équivalents, sur des simulateurs comportementaux récents
This thesis deals with the behavioural modelling of operational amplifiers in the [25°C, 200°C] temperature range. The implementation of a high temperature model needs a reliable 25°C model. This macro model, based on the classical operational amplifier equations, is implemented with independent macro functions giving its modularity and specificity. In this way, we have a model readily customisable regarding the application. The existing models are then upgraded with this model enabling trade-off on accuracy and CPU time. The main features variations with temperature study s hows that it was possible to smooth them Kith polynomials. These variations are implemented at the model level by temperature dependant parameters, the use of these functions having few effects on CPU time. The simulation-experiment accuracy, twice worse the constant temperature model one, however keeps a range compatible Kith analogue circuit simulation in the [25°C, 200°C] range

Viscoplastic fluids do not flow unless they are sufficiently stressed. While in some flows this leads to unwanted features, this property can also be exploited in order to produce novel flow features. One example of such flows are visco-plastically lubricated (VPL) flows, in which a viscoplastic fluid is used to stabilize the interface in a multi-layer flow, far beyond what might be expected for a typical viscous-viscous interface. Here we extend this idea by considering the encapsulation of droplets within a viscoplastic fluid, for the purpose of transportation, e.g. in pipelines. The main advantage of this method, compared to others that involve capillary forces is that significantly larger droplets may be stably encapsulated, governed by the length scale of the flow and yield stress of the encapsulating fluid. We explore this setup both analytically and computationally. We show that sufficiently small droplets are held in the unyielded plug of the Poiseuille flow. As the length or radius of the droplets increase the carrier fluid eventually yields, potentially breaking the encapsulation. We study this process of breaking and give estimates for the limiting size of droplets that can be encapsulated.
Applied Science, Faculty of
Mechanical Engineering, Department of
Graduate

This thesis is a collection of four essays dealing with issues on the verge of macroeconomics and finance. The first two chapters are joint with Bianca De Paoli. In the first one, we try to analyze factors causing risk premia to vary over time. The second one is an attempt to understand how these factors - manifesting themselves through swings in the desire to save for precautionary reasons - affect monetary policy. We show analytically that in endowment economies, procyclical recession expectations can 'outweigh' countercyclical changes in 'risk-aversion' - generating counterfactual risk-premium behavior. However, allowing shocks or habits to be sufficiently persistent, or explicitly accounting for the impact of habits on consumption, suffices to generate countercyclical recession risks and risk premia. We also show that taking note of precautionary saving motives justifies an accommodative policy bias in the face of persistent, adverse disturbances. Equally, policy should be more restrictive - i.e. 'lean against the wind' - following positive shocks. Both of these essays rely on approximate solutions to a simple, external habit model. In the third chapter, I derive closed form formulae for the model's solution. I then use these formulae to estimate the model and analyze its ability to jointly fit consumption growth and asset price data. I find no specification capable of simultaneously matching these data and argue that 'exotic' shock distributions are an unlikely panacea. In general, however, closed form formulae for asset prices cannot be derived analytically and need to be approximated. The final chapter proposes a method of doing exactly that. In contrast to several alternative approaches, the approximating function is not restricted to be a polynomial in state variables. This flexibility and efficient use of nested solutions can allow 'low-order' formulae to exceed the accuracy of higher-order perturbation approximations.

Dissertação para obtenção do Grau de Mestre em Engenharia Informática
In recent years, several approaches have been proposed for improving application performance on multi-core machines. However, exploring the power of multi-core processors remains complex for most programmers. A Macro-component is an abstraction that tries to tackle this problem by allowing to explore the power of multi-core machines without requiring changes in the programs. A Macro-component encapsulates several diverse implementations of the same specification. This allows to take the best performance of all operations and/or distribute load among replicas, while keeping contention and synchronization overhead to the minimum. In real-world applications, relying on only one server to provide a service leads to limited fault-tolerance and scalability. To address this problem, it is common to replicate services in multiple machines. This work addresses the problem os supporting such replication solution, while exploring the power of multi-core machines. To this end, we propose to support the replication of Macro-components in a cluster of machines. In this dissertation we present the design of a middleware solution for achieving such goal. Using the implemented replication middleware we have successfully deployed a replicated Macro-component of in-memory databases which are known to have scalability problems in multi-core machines. The proposed solution combines multi-master replication across nodes with primary-secondary replication within a node, where several instances of the database are running on a single machine. This approach deals with the lack of scalability of databases on multi-core systems while minimizing communication costs that ultimately results in an overall improvement of the services. Results show that the proposed solution is able to scale as the number of nodes and clients increases. It also shows that the solution is able to take advantage of multi-core architectures.
RepComp project (PTDC/EIAEIA/108963/2008)

Marsupials and eutherians are the two principal groups of modern mammals. Mammalian immunological studies, to date, have focused on eutherian systems with little or no comprehensive work having been carried out on marsupials. This project investigates the functional and developmental aspects of T-cell responses in the marsupial, Macropus eugenii (Tammar wallaby) in both adults and pouch young at various stages of development. Determination of the age at which the Tammar wallaby immune system becomes competent has been examined through the use of cellular and molecular studies carried out on developing pouch young tissue. The capacity for generating an immunological response in adult and pouch young marsupials has been studied by following cellular proliferation in response to mitogens or mixed lymphocyte culture (MLC). After examining adult responses to mitogens and allogenic lymphocytes, optimised conditions were then used to examine the development of responsiveness in pouch young. Several further tests were conducted and findings shown. The study has shown that the earliest age at which Macropus eugenii is capable of mounting a T-cell mediated immune response is between 5 to 13 days post-partum
Doctor of Philosophy (PhD)

This thesis presents a new actuator system consisting of a micro-actuator and a macro-actuator coupled in parallel via a compliant transmission. The system is called the Parallel Coupled Micro-Macro Actuator, or PaCMMA. In this system, the micro-actuator is capable of high bandwidth force control due to its low mass and direct-drive connection to the output shaft. The compliant transmission of the macro-actuator reduces the impedance (stiffness) at the output shaft and increases the dynamic range of force. Performance improvement over single actuator systems was expected in force control, impedance control, force distortion and reduction of transient impact forces. A set of quantitative measures is proposed and the actuator system is evaluated against them: Force Control Bandwidth, Position Bandwidth, Dynamic Range, Impact Force, Impedance ("Backdriveability'"), Force Distortion and Force Performance Space. Several theoretical performance limits are derived from the saturation limits of the system. A control law is proposed and control system performance is compared to the theoretical limits. A prototype testbed was built using permanenent magnet motors and an experimental comparison was performed between this actuator concept and two single actuator systems. The following performance was observed: Force bandwidth of 56Hz, Torque Dynamic Range of 800:1, Peak Torque of 1040mNm, Minimum Torque of 1.3mNm. Peak Impact Force was reduced by an order of magnitude. Distortion at small amplitudes was reduced substantially. Backdriven impedance was reduced by 2-3 orders of magnitude. This actuator system shows promise for manipulator design as well as psychophysical tests of human performance.

This doctoral thesis is a collection of four papers on the analysis of the term structure of interest rates with a focus at the intersection of macroeconomics and finance. "Risk in Macroeconomic Fundamentals and Bond Return Predictability" documents that factors related to risks underlying the macroeconomy such as expectations, uncertainty and downside (upside) macroeconomic risks are able to explain variation in bond risk premia. The information provided is found to be, to a large extent, unrelated to that contained in forward rates and current macroeconomic conditions. "Out-of-sample bond excess returns predictability" provides evidence that macroeconomic variables, risks in macroeconomic outcomes as well as the combination of these different sources of information are able to generate statistical as well as economic bond excess returns predictability in an out-of-sample setting. Results suggest that this finding is not driven by revisions in macroeconomic data. The term spread (yield curve slope) is largely used as an indicator of future economic activity. "Re-examining the predictive power of the yield curve with quantile regression" provides new evidence on the predictive ability of the term spread by studying the whole conditional distribution of GDP growth. "Modeling and forecasting the yield curve by extended Nelson-Siegel class of models: a quantile regression approach" deals with yield curve prediction. More flexible Nelson-Siegel models are found to provide better fitting to the data, even when penalizing for additional model complexity. For the forecasting exercise, quantile-based models are found to overcome all competitors.

Diss. Stockholm :  Stockholm School of Economics, 2014. Introduction together with 4 papers.

In a conventional hardware design flow, the compilation process to create the physical circuit on the FPGA takes a long time. HMFlow is a design flow that reduces the compilation time by using pre-compiled modules called hard macros. HMFlow uses System Generator to create the designs, which are then converted to hard macros. The hard macro creation process takes a long time and a possible solution is a hard macro generator called XdlCoreGen, which is described in this thesis. XdlCoreGen can quickly create fully mapped and placed hard macros using XDL. XDL is a human readable design format that describes an FPGA and can be manipulated to configure the FPGA. XdlCoreGen also provides a framework to configure a Xilinx Virtex4 FPGA using XDL. In addition to XdlCoreGen, this thesis also describes the FPGA configuration methodology using XDL. This thesis also describes a cache based router, where instead of finding a route, a pre-generated route is used to route the hard macros generated by XdlCoreGen. This thesis also presents test results using XdlCoreGen. However, the main focus of this thesis will be the speed of hard macro generation by XdlCoreGen.

Book Summary: This work is the fourth Small Wars Journal anthology focusing on radical Sunni Islamic terrorists and insurgent groups. It covers this professional journals writings for 2016 and is a compliment to the earlier Global Radical Islamist Insurgency anthologies that were produced as Vol. I: 2007-2011 (published in 2015) and Vol. II: 2012-2014 (published in 2016) and Jihadi Terrorism, Insurgency, and the Islamic State spanning 2015 (published in 2017). This anthology, which offers well over 900 pages of focused analysis, follows the same general conceptual breakdown as the earlier works and is divided into two major thematic sectionsone focusing on Al Qaeda and Islamic state activities in 2016 and the other focusing on US-Allied policies and counterinsurgent strategies.

Le thème principal de cette thèse est celui des liens macro financiers. J’ai couvert trois questions différentes liées à ce sujet. Dans le premier chapitre, Gaël Giraud et moi-même développons un modèle pour la zone euro en réponse à de nombreuses critiques des modèles de politiques avant le GFC et en mettant l’accent sur l’interaction entre le secteur financier et la macroéconomie. Les deuxième et troisième chapitres portent sur le comportement du secteur financier au lendemain de la crise financière mondiale et ses implications pour la macroéconomie. Le chapitre 2 examine la pratique de l’abstention à l’égard des emprunteurs en difficulté. La question finalement pertinente dans ce chapitre est de savoir dans quelle mesure ce comportement influe sur l’économie réelle. Enfin, le troisième chapitre met en lumière un épisode de manipulation sur les marchés des matières premières. Cette prétendue manipulation n’était apparemment possible qu’en raison de la position dominante des banques sur le marché pendant la période qui a précédé la crise et par la suite. En fin de compte, je quantifie les effets d’un tel comportement et apporte la preuve d’un changement structurel du marché manipulé au cours de la période de manipulation alléguée. Le premier chapitre exploite un ensemble de données au niveau des banques, tandis que dans les chapitres 2 et 3, je développe des modèles macroéconomiques structurels. En particulier, le modèle de système dynamique du deuxième chapitre est une innovation. Cette catégorie de modèles, et plus particulièrement un modèle de la taille que nous développons, n’a jamais été estimée et utilisée par la suite pour l’analyse des politiques
The main theme of this thesis are macro-financial linkages. I covered three different questions related to this topic. In the first chapter Gaël Giraud and I develop a model for the Euro Area answering to many of the critiques of policy models before the Global Financial Crisis and with a focus on the interaction between the financial sector and the macroeconomy. The second and third chapter focus on behaviour of the financial sector in the aftermath of the Global Financial Crisis and its implications for the macroeconomy. Chapter 2 investigates the practice of forbearance towards stressed borrowers. The ultimately relevant question in this chapter is to what extend there is a feedback to the real economy due to this behaviour. Finally, the third chapter sheds light on an episode of manipulation in commodity markets. This alleged manipulation was apparently only possible due to the dominant market position banks took in the run up to the crisis and thereafter. Ultimately I quantify the effects of such behaviour and provide evidence of a structural change of the manipulated market during the period of alleged manipulation. The first chapter exploits a bank level dataset, whereas in chapter 2 and 3 I develop structural macroeconomic models. Especially the dynamical system model in the second chapter is an innovation. This class of models and more specifically a model of the size we develop has never been estimated and subsequently used for policy analysis

Cette dissertation se compose de trois essais qui examinent le rôle de la dette souveraine dans l'économie. Le premier des essais explore la question de la dette optimale par la liquidité et constate que tant que la dette est soutenable, l'augmentation de la dette a des avantages. L'augmentation des niveaux d'endettement encourage les acheteurs à entrer sur le marché en améliorant la liquidité et en abaissant le taux d'intérêt. Dans le deuxième chapitre, je présente un modèle d'QE, où l'impact du QE sur le taux d'intérêt dépend de l'étanchéité du marché, qui est déterminée par des actions d'investisseurs avec habitat préférée. En outre, il existe un effet négatif pour la liquidité, qui n'est existé pas dans l'autres modèles de QE. Le troisième chapitre analyse le rôle des agences de notation dans les crises de la dette souveraine. Le montre que les notations de crédit ne sont pas de bons prédicteurs des événements de crédit lorsqu'on les compare à un simple modèle de référence comprenant des variables macroéconomiques usuelles. Dans un second temps, le papier utilise des données à plus haute fréquence pour un sousensemble de pays afin d'analyser le lien entre notations de crédit et spreads. Les résultats indiquent que les spreads réagissent fortement aux changements de notation, surtout lorsqu'elles ont lieu à la baisse et dans la catégorie « non-investissement ». Les résultats restent valides lorsqu'on les soumet à un ensemble de tests supplémentaires
This dissertation consists of three essays that examine the role of sovereign debt in the economy. The first of the essays explores the question of optimal debt through liquidity and finds that as long as debt is below a sustainability threshold, increasing debt is beneficial. Increasing debt levels encourages buyers to enter the market improving liquidity and lowering yields. The result is built by combining two strands of literature, market thinness and default probabilities in a unified search-theoretic model of over the counter traded debt. The model also predicts that liquidity and yields in smaller countries that are not able to issue much debt, suffer more from shocks to income. A panel VAR with data on Eurozone countries confirms this prediction. In the second chapter I present a search theoretic model of over-the-counter debt with quantitative easing that explains why interest rates fall more in some countries than others. The study is motivated by our finding that the higher rated a Eurozone country was, the more yields fell. Since the central banks purchase similar amounts in each Eurozone country, it cannot explain the difference in impact on yields. We explain the differential through two channels. Firstly, in markets for highly rated bonds, there are more preferred habitat investors and subsequently fewer sellers. Sellers therefore have a higher bargaining power and can negotiate a higher price. Those preferred habitat investors' have a less elastic demand for bonds, and wil continue to buy them even though it becomes harder to find sellers and their bargaining power diminishes. This excess demand due to market tightness has an additional positive impact on the price. Finally, central bank purchases initially improve liquidity, especially in high risk countries where the measure of buyers is small, but as it tapers the purchases, liquidity is reduced well below pre-purchase levels especially in those countries, that is the cost of quantitative easing. We estimate the share of preferred habitat investors in each Eurozone country from the ECB's Securities and Holdings Statistics and confirm the differential impact on yields with a panel VAR and an event study. The third chapter examines credit ratings and their impact on sovereign debt crises and yields. The results show that credit ratings are poor predictors of sovereign debt crises. A parsimonious model of fundamentals is better at predicting Emerging Market debt crises than credit ratings. Furthermore, rating changes tend to lag events significantly. Investors should therefore ignore rating changes given that they do not contain new information. Estimating the impact of rating changes on yields, we find evidence of contrary, yields react especially strongly to downgrades of non-investment grade debt. This can be due to regulatory constraints where a downgrade reduces the value of debt as a collateral

Au cours de ma thèse, j'ai mené des recherches macroéconomiques appliquées sur différents sujets, allant des effets de la polarisation des emplois sur la réallocation des travailleurs aux effets de la politique monétaire sur la structure du capital des entreprises et les décisions financières. Cette thèse recueille trois articles sur ces arguments. L'article principal de la thèse est mon job market paper. Ce travail m'a donné l'opportunité d'explorer en détail les effets du changement technologique sur la structure professionnelle des marchés du travail, mais aussi ses effets sur la réallocation des travailleurs entre les emplois et le processus de tri des compétences en emplois. En d'autres termes, l'article répond à ces questions: comment les travailleurs utilisent-ils l'échelle professionnelle lorsque l'innovation technologique change sa structure? Quelles sont leurs possibilités d'emploi, compte tenu de leurs compétences, lorsque la technologie change? Et quelles compétences les employeurs recherchent-ils? Cet argument m'a toujours intrigué, et sa pertinence attire actuellement l'attention des gouvernements et des décideurs dans de nombreuses économies développées. Ma recherche s'écarte de ces faits pour analyser quels sont les effets du changement technologique sur les travailleurs et les entreprises. En particulier, il montre -comme cela a déjà été documenté dans la littérature sur la polarisation des emplois- que l'innovation technologique remodèle la structure professionnelle de l'économie en détruisant certains types d'emplois. Cependant, je montre que l'innovation technologique modifie la demande de compétences dans chaque profession de manière à avoir des effets hétérogènes sur les travailleurs en termes de mobilité de la main-d'œuvre, d'opportunités d'emploi et de qualité de matching. En particulier, ce papier est le premier à montrer que la technologie - en provoquant la polarisation du marché du travail - déclenche de grands mouvements du haut vers le bas de l'échelle des emplois, de nombreux travailleurs finissant dans des professions moins rémunérées et moins qualifiées. Les effets du changement technologique sur les résultats et la dynamique du marché du travail sont également examinés dans le deuxième chapitre de cette thèse. En particulier, ce travail, en collaboration avec Joanne Tan, montre comment le changement technologique peut expliquer l'augmentation de la pénurie de main-d'œuvre (occupational shortage) et comment les différents segments du marché du travail y réagissent Dans le dernier chapitre de la thèse, je m'intéresse à la relation entre la politique monétaire et la décision de rachat d'actions. Ce sujet n'a aucun lien avec le précédent, mais j'ai toujours été intéressé par la façon dont les macro-variables peuvent influencer les décisions des gestionnaires au niveau micro. Dans ce travail, conjointement avec Assia Elgouacem, nous utilisons des données au niveau de l'entreprise et montrons que les sociétés américaines rachètent davantage leurs propres actions en période de politique monétaire accommodante, c'est-à-dire lorsque le coût de la dette est faible. En fait, nous montrons que si la courbe de rendement d'une entreprise s'ajuste dans la direction prévue par la politique monétaire, c'est-à-dire que le coût de la dette diminue, l'entreprise émettra davantage d'obligations pour lever des fonds à moindre coût. Cependant, ils vont utiliser la majeure partie de ces nouvelles liquidités pour financer un programme de rachat plutôt que d'investir dans de nouveaux capitaux et emplois. Cet effet d'éviction des rachats sur les nouveaux investissements et l'emploi suscite des doutes car il atténue la transmission de la politique monétaire
During my PhD I conducted applied macroeconomic research on several different topics, spanning from the effects of job polarization on workers reallocation to the effects of monetary policy on firms capital structure and financial decisions. This thesis collects three articles on these arguments. The main article of the thesis is my job market paper. This work gave me the opportunity to explore in detail the effects of technological change on the occupational structure of labor markets, but also its effects on the reallocation of workers across jobs and the process of sorting skills to jobs. Or in other words, the paper answers these questions: how do workers use the job ladder when technological innovation changes its structure? What are their job opportunities, given their skills, when technology changes? And what skills do employers look for? This argument always intrigued me, and its relevance is raising the attention of governments and policy makers in many developed economics. My research departs from these facts to analyze what are the heterogeneous effects of technological change on workers and firms. In particular, it shows -as already documented in the literature on job polarization- that technological innovation reshapes the occupational structure of the economy by destroying some type of jobs. However I show that, at the same time, technological innovation changes the demand for skills in each occupation such that it has heterogeneous effects across workers in terms of labor mobility, job opportunities and match quality. In particular, this paper is the first to show that technology - by causing the polarization of the labor market- triggers large movements from the top to the bottom of the job ladder, with many workers ending up in lower paying and lower qualifying occupations just after the disruptive effects of technological change were consumed. The effects of technological change on labor market outcomes and dynamics is explored also in the second chapter of this thesis. In particular, this work, joint with Joanne Tan, shows how technological change can explain the raise of occupational shortage. More interestingly, it shows how different segments of the labor market react to occupational shortage. In the last chapter of the thesis, I turn my attention to the relationship of monetary policy and corporate decision of share repurchase. This topic is fully unrelated from the previous one, but I have always been interested on how macro-variables can influence managers decisions at micro level. In this work, joint with Assia Egouace, we use firm-level data and show that American corporations buyback more their own shares in period of accommodating monetary policy, i.e. when the cost of debt is low. In fact we show that if the yield curve of a firm adjusts in the direction predicted by monetary policy, i.e. the corporate cost of debt diminishes, the firm is going to issue more bonds to raise money at lower costs. However, they are going to use most of these new liquidity to finance a repurchase program rather than investing into new capital and employment. This crowding out effect of buybacks on new investment and employment casts doubts since it attenuates the transmission of monetary policy

The present thesis is a collection of three essays in Macro Finance. The first essay examines the effects of industry competition on the cross-section of credit spreads and levered equity returns. I build a quantitative model where firms make investment, financing, and default decisions subject to aggregate and firm-specific risk. Firms operate in heterogeneous industries that differ by the intensity of product market competition. Higher competition reduces profit margins and increases default risk for debtholders. Equityholders are protected against default risk due to the option value arising from limited liability. In equilibrium, competitive industries are characterized by higher credit spreads, but lower expected equity returns. I find strong empirical support for these predictions across concentration quintiles. Moreover, the calibrated model generates cross-sectional variation in leverage and valuation ratios in line with the data. The second essay provides new evidence that imperfect competition is an important channel for time varying risk premia in asset markets. To this end, we build a general equilibrium model with monopolistic competition and endogenous firm entry and exit. Endogenous variation in industry concentration generates countercyclical markups, which amplifies macroeconomic risk. The nonlinear relation between the measure of firms and markups endogenously generates countercyclical macroeconomic volatility. With recursive preferences, the volatility dynamics lead to countercyclical risk premia forecastable with measures of competition. Also, the model produces a U-shaped term structure of equity returns. The final essay explores the interactions between yield curve dynamics and nominal government debt maturity operations in a New Keynesian model with endogenous bond risk premia. Violations of debt maturity neutrality occur when the yield curve slope is nonzero in a fiscally-led policy regime. When the risk profiles of government liabilities differ, rebalancing the maturity structure changes the government cost of capital. In the fiscal theory, changes in discount rates affect inflation through the intertemporal government budget equation. When the yield curve is upward-sloping (downward-sloping), the fiscal discount rate channel implies that shortening the maturity structure has contractionary (expansionary) effects.
Business, Sauder School of
Finance, Division of
Graduate

Do financial intermediaries influence firms’ (real and financial) outcomes? Are there interactions with monetary and macroprudential policy? This thesis tackles those questions from multiple perspectives. The first chapter asks whether monetary policy shocks alter the maturity structure of US corporate debt. I find that looser monetary conditions lengthen non-financial firms’ debt maturity, especially among very big corporations and driven by increased risk-taking by bond-market investors. The second and third chapter analyze the effects of prudential capital controls on corporate debt and real outcomes, looking at the recent experience of Colombia. Capital controls are shown to reduce corporate debt during a boom - either directly, or indirectly, i.e. by amplifying the contractionary effects of higher policy rates on banks’ credit supply - thereby improving firm performance during the bust.
Influyen los intermediarios financieros en los resultados (reales y financieros) de las empresas? ¿Existen interacciones entre la política monetaria y macroprudencial? Esta tesis aborda estas cuestiones desde diferentes ángulos. El primer capítulo estudia si los shocks de política monetaria alteran la estructura de vencimiento de la deuda corporativa estadounidense. Los resultados apuntan a que unas condiciones monetarias más flexibles alargan el vencimiento de la deuda de las empresas no financieras, especialmente entre las corporaciones muy grandes y están impulsadas por un incremento del riesgo asumido por los inversores del mercado de bonos. El segundo y tercer capítulo analizan los efectos de los controles prudenciales de capital sobre la deuda corporativa y los efectos reales, basándose en la experiencia reciente de Colombia. Se demuestra que los controles de capital reducen la deuda corporativa durante un auge, mejorando así el desempeño de las empresas durante la crisis, ya sea directamente o indirectamente, es decir, amplificando los efectos contractivos de un incremento de los tipos de interés oficiales sobre la oferta crediticia de los bancos.

O presente relatório resulta do estágio curricular subordinado ao tema Clínica de Animais Selvagens e de Zoo, decorrido no Zoo de Dalas (E.U.A.) e no Zoo da Maia, com duração de 97 dias partilhados entre as duas instituições. Surge na conclusão do Mestrado Integrado em Medicina Veterinária da Universidade de Évora A doença periodontal refere-se, geralmente, a alterações que envolvem os dentes e os tecidos adjacentes da cavidade oral e apresenta, na maioria das vezes, etiologia bacteriana associada a alterações da flora microbiana oral. A necrobacilose oral é uma causa comum de morbilidade e mortalidade nos animais do género Macropus, podendo ser o resultado do agravamento da doença periodontal e manifestando-se por lesões supurativas no tecido mole e ossos da face, sendo o Fusobacterium necrophorum o principal agente causal; ABSTRACT: Zoo and Wildlife Medicine The following report results from the externship in Zoo and Wildlife Medicine lasting 97 days, shared between Dalas Zoo (U.S.A.) and Maia Zoo. Appears as the conclusion of the Master in Veterinary Medicine at the University of Évora Periodontal disease generally describes the conditions involving the teeth and adjoining tissues of the oral cavity and presents mostly a bacterial etiology associated with changes in oral microbial flora. Oral necrobacillosis is a common cause of morbidity and mortality in animals of the genus Macropus and may be the result of the progress of periodontal disease, manifesting as suppurative lesions of the soft tissue and bones of the face and the main causal agent seems to be Fusobacterium necrophorum.

L’objectif de cette thèse est de proposer une nouvelle approche de l’organisation de la structure sonique, dans le cadre de la composition musicale. L’organisation du son sera traitée à différentes échelles, grâce à des méthodes algorithmiques, engendrant ainsi ce que nous appellerons « macro-son ». Le terme « macro » fait appel à une échelle de perception relative, et signifie qu’une forme est composée. Les trois échelles temporelles (micro, méso, macro) servent donc de référentiel les unes aux autres, et l’existence d’un phénomène peut naturellement faire l’objet d’une observation hiérarchique, ouvrant la voie à une nouvelle stratégie pour la conception de « macro-sons ». Cette hiérarchie est le lieu du développement de différentes couches, en continuum vis-à-vis des attributs de la perception. L’échelle de perception est alors relative au temps, et nous pouvons également en proposer des divisions comme « méso » et « micro ». Le questionnement principal de cette thèse serait alors de savoir comment construire un phénomène sonore macroscopique à partir de ses entités microscopiques. Ainsi, le terme « macro-son » concerne une structure sonique organisée possédant une complexité croissante du niveau micro au niveau macro. On s’attendra également à observer un phénomène d’émergence lors de la conception du macro-son suivant notre stratégie. Au sein de cette hiérarchie présentant plusieurs niveaux, la composition du macro-son contribue à la formation d’une structure, devenant elle-même une forme musicale. Les conséquences perceptives de cette perspective de conception du macro-son sont nombreuses et seront abordées dans cette dissertation. La recherche que nous présentons ici est rattachée à une pratique compositionnelle visant, et aboutissant, à des résultats concrets. Cette orientation fut la source d’inspiration initiale et la base de cette recherche sur la conception du macro-son. Cette stratégie de conception tient compte des approches algorithmiques existant auparavant, et étend l’acte compositionnel au matériau sonore lui-même. De nouveaux moyens de formalisation et de structuration furent alors nécessaires. L’objectif visé par de tels questionnements est de fournir des points de repère utiles et aisément compréhensibles, en tirant parti du potentiel nouveau offert par le travail de micro-composition du son. De tels exemples compositionnels ne sont pas envisagés ici dans le cadre de l’approche traditionnelle de la composition algorithmique (automatique). Ils sont vus comme la translation du paradigme de composition timbrale, qui crée une forme musicale auto-émergente. Par la capacité à atteindre la microstructure du son, le processus est devenu « la composition du son », puis « la composition avec le son ». Le processus qui consiste à composer le son lui-même a été enrichi par la possibilité de définir la structure formelle et la complexité en accédant aux morphologies structurelles sur plusieurs échelles. Le processus de conception du macro-son devra être transparent vis-à-vis des décisions compositionnelles qui construisent la structure. Un paradigme consistant à suivre strictement des processus musicaux formalisés peut par exemple être décelé dans la musique de Xenakis, ou d’autres qui utilisent des concepts mathématiques et des modèles computationnels comme cadres formels de leur composition. Le contrôle de l’espace timbral des objets sonores fournit des connexions formelles aux structures musicales. Nous décrirons les aspects temporels, comme les opérations concernant le continuum, l’émergence, ainsi que les processus morphologiques appliqués à des structures soniques, et aussi des idées inspirées de phénomènes naturels. Depuis les approches traditionnelles jusqu’aux nouvelles philosophies de la pensée compositionnelle, comme le contrôle de la complexité, l’intérêt central réside toujours dans l’expression des différents aspects de la composition du macro-son. Les différentes méthodes de contrôle de la complexité et l’introduction du comportement émergent de la structure sonore constituent le point clef à questionner pour étudier et améliorer les outils existants, dans le but de concevoir l’objet macro-sonore. La conception du macro-son englobera les actes d’organisation du son au sein d’une approche « bottom-up » (ascendante) dans l’espace sonique, du niveau micro au niveau macro. Comme pour la composition d’œuvres musicales, les stratégies descendantes (top-down) et ascendantes (bottom-up) sont introduites pour permettre un contrôle des différents niveaux de la structure sonore. Ceci a également des conséquences sur les aspects temporels. Les processus agissant au niveau micro-temporel ont été développés pour gérer les éléments micro-sonores, et permettre l’organisation des particules sonores. Nous observons que l’approche théorique est également valide dans le cadre de la pratique compositionnelle, grâce au développement d’outils logiciels de travail en temps réel. Des applications novatrices développées pendant cette recherche, comme Stochos, Cosmos et CosmosF vont encore plus loin, avec des modèles stochastiques de distribution d’événements permettant le contrôle en temps réel (grâce aux nouvelles possibilités de programmation informatique) de la complexité et de l’espace timbral en continuum. Quant aux problématiques de visualisation des structures soniques complexes, elles ne furent pas oubliées, et certaines expérimentations seront présentées. Finalement, l’application CosmosF est tournée vers la synthèse de structures macro-sonores ayant des attributs écologiques, pour engendrer des résultats sonores intéressants d’un point de vue perceptif et utiles pour la composition. Le système qui fournit le résultat sonique possède également des capacités d’auto-organisation. Certains principes de la cybernétique ont été évalués de façon critique dans le chapitre correspondant, notamment l’expression des interdépendances existant entre les composants du système, ses dynamiques, et le couplage avec l’environnement environnement. Ce travail vise à donner lieu à une auto-évolution de type écologique, reposant sur un échange interactif entre le système et les conditions extérieures. L’objectif est de formuler quelques nouveaux principes et d’en présenter une ébauche, pour dessiner un réseau de concepts ouvrant de nouvelles voies pour la synthèse sonore
The main objective of this thesis is to propose a novel approach for the organisation of sonic structures with the aim of musical composition. This organisation of sonic structures will be treated on different time scales thanks to algorithmic methodes. The term “Macro” proposes a relative scale perception, and it signifies a combining form as large, great, long etc. The scale perception is relative to time, and by that we can propose divisions to it like ‘meso’ and ‘micro’. Thus all the three time-scales are referential to each other and the existence of the phenomena can be observed naturally on hierarchical levels, which proposes also a strategy for the design of the “macro sound”. The principal question of the thesis would be how to build a macroscopic phenomena of sound starting from its microscopic entities. The term “Macro Sound” concerns a sonic structure possessing a complexity across the micro level up to the macro level. And regarding our strategy, we would expect to observe emergent phenomena according to our conception of the macro sound. The composition of macro sound contributes to a hierarchical formation of a structure presenting multiple levels, which itself becomes a musical structure. The perceptual consequences of such a perspective for the conception of macro sound are numerous. This research is attached to compositional practice in order to observe its concrete results. This orientation establishes the initial inspirations and the basis of the research for the conception of macro sound. This conceptual act mainly considers the algorithmic approach and aims to extend it towards the act of composition of the sound material itself. Therefore new situations arising from the use of computers for building musical processes will be planned. These acts are not evaluated here in the frame of the traditional approach to algorithmic (automatic) composition, but to the transition of the timbre composition establishing a musical form by itself. Within the ability to reach the microstructure of sound, the process above has become the composition of sound. The process of composing the sound itself has gained the ability to deliver the formal structure and complexity by accessing the morphologies in different dimensions of the structure. The process of macro sound design should be transparent to compositional decisions, which build the formal structure along with the different appropriate compositional sonic tasks. A paradigm of following strict formalized musical processes can be witnessed for example in the music of I. Xenakis and other musicians who use mathematical concepts and computational models as formal frameworks for composition. Controlling the timbre space of sound objects provides formal connections in musical structure. Temporal aspects such as operations in continuum, emergency, morphological processes on sonic structures and even derivation of ideas from natural phenomena are described. From traditional approaches to the new philosophies in compositional thinking such as controlling the complexity, the central concern remains as expressing the various aspects of macro sound composition. Different methodologies for controlling the complexity and the introduction of emergent behavior of the sonic structure constitutes the main key of questioning the existing tools and also how to develop further ones. The design of macro sound will be encapsulating the acts of organizing the sound within a bottom-up approach from micro level to the macro level operations on the sonic space. Considering the compositional strategies of musical forms, top-down and bottom-up organizational methods are introduced from the micro to macro level in the sonic space. With the bottom-up approach, the formal transition in the sonic structures can be accomplished at the bottom level by changing the micro-parameters, which belong to sonic entities as known the elementary particles of the whole structure. Observation that the theory can be equally validated on the practical compositional level has been possible thanks to some real-time operating software developments. Applications like Stochos, Cosmos and CosmosF bring the stochastic event distribution models a step forward by means of controlling complexity and timbral space in continuum and by utilizing the modern programming facilities. Also the visualization aspect of complex sonic structures has not been left and some experiments are presented. Finally, a version of CosmosF application focuses on synthesizing macro-sound structures with certain ecological attributes to obtain perceptually interesting and compositionally useful results. The system, which delivers the sonic result is designed as a self organizing system. Certain principles of cybernetics have been critically assessed in the chapter in terms of interdependencies among system components, system dynamics and the system/environment coupling. It is aiming towards a self-evolution of an ecological kind, applying an interactive exchange with its external conditions. The goal is to formulate some new principles and present its sketches here by arriving to a network of concepts suggesting new ideas in sound synthesis

Résumé : La reproduction entraîne des dépenses énergétiques importantes chez les femelles mammifères. Ces dépenses sont supposées diminuer l'énergie disponible pour d'autres traits positivement corrélés à l'aptitude phénotypique et augmenter les besoins d'alimentation. Toutefois, des différences individuelles dans la capacité d'acquisition et d'allocation peuvent masquer l'impact négatif de l'effort reproducteur. La manipulation expérimentale de l'effort reproducteur et le contrôle statistique des effets individuels sont deux approches puissantes et complémentaires mises en œuvre dans le cadre de mon étude afin de contrôler pour l'hétérogénéité individuelle. Elles ont permis de montrer clairement un coût de la reproduction chez le kangourou gris de l'Est (Macropus giganteus). Dans un premier temps, nous avons trouvé que le coût de la reproduction affectait le montant d'énergie alloué à certaines fonctions somatiques (CHAPITRE I). L'effort reproducteur diminuait le gain de masse et la croissance des jambes pour des intervalles de capture supérieurs à deux ans. Chez les femelles non manipulées, un effet négatif sur le gain de masse était aussi observable pour un intervalle inférieur à 3 ans. À l'échelle de deux événements successifs de reproduction, le gain de masse et dans une moindre mesure la croissance des bras, mais non des jambes diminuaient avec un effort reproducteur plus important à la précédente reproduction. Ensuite, nous avons démontré qu'il y avait un coût de la reproduction en terme de futur succès reproducteur (CHAPITRE II). Les individus dont l'effort reproducteur avait été diminué expérimentalement produisaient davantage de jeunes qui survivaient au stade 'LPY', âgés approximativement de 7 mois, que les femelles contrôles. Ils diminuaient également davantage leur taux de reproduction en allongeant l'intervalle entre les naissances, mais la survie au sevrage n'était pas affectée. Le CHAPITRE III montre que les femelles adaptaient leur comportement alimentaire en fonction de leur statut reproducteur. En comparaison avec les individus manipulés ou ayant perdu leur jeune, les femelles allaitantes augmentaient leur temps passé à s'alimenter durant la journée, l'intensité de leurs bouchées et de leur mastication sans impliquer de compromis avec la vigilance. Nous avons aussi découvert que la survie au sevrage du jeune précédent menait à une augmentation du taux de bouchées pour l'année en cours. Les CHAPITRES I et II ont mis en évidence l'effet non négligeable des différences individuelles sur la détection des coûts de la reproduction. En effet, en l'absence de manipulation expérimentale ou de contrôle statistique, aucun compromis n'était détecté autant en terme de croissance que de prochaine reproduction. Au contraire, des corrélations positives entre l'effort reproducteur et les autres traits ont été trouvées. Le CHAPITRE I suggérait notamment que cette variabilité du succès reproducteur était liée à l'hétérogénéité individuelle dans le gain de masse maternelle qui augmentait la survie du jeune. Dans le CHAPITRE II, une corrélation positive entre les probabilités d'avoir un 'LPY' lors de deux événements successifs de reproduction suggérait que certaines femelles étaient capables de mener à bien ou non leur reproduction, mais cela indépendamment de l'effort reproducteur précédent. Enfin dans le dernier CHAPITRE (III), l'effet aléatoire était significatif dans l'analyse de différents comportements d'alimentation, ce qui pourrait être lié aux différences de gain de masse des femelles présentées dans le CHAPITRE I. Certaines contraintes individuelles affectant le coût de la reproduction ont été identifiées. La masse et la condition corporelle augmentaient le succès reproducteur et diminuaient l'intervalle entre deux naissances successives (CHAPITRES I et II), mais contrairement à de précédentes études le comportement d'alimentation des femelles n'était pas affecté par leur masse (CHAPITRE III). L'âge des individus avait également une influence. Les jeunes femelles croissaient davantage, avaient aussi une prise alimentaire plus importante et subissaient un coût de reproduction supérieur. Ce dernier se traduisait par un taux d'échec plus élevé à la reproduction suivante si les jeunes femelles avaient eu un jeune l'année précédente (CHAPITRES I, II et III). Des contraintes environnementales fortes influençaient la reproduction des femelles. La croissance, le succès reproducteur, l'intervalle entre les naissances et les comportements d'alimentation variaient suivant le site et l'année d'étude. Le site du Promontory et l'année 2011 apparaissaient particulièrement limitants. En effet en 2011, le gain de masse et le succès reproducteur ont diminué et l'intervalle de naissance et la prise de nourriture pour les femelles allaitantes ont augmenté (CHAPITRE I,II et III). Nous cherchions également à mettre au jour une allocation différentielle des mères suivant le sexe de leur jeune. Si le coût supérieur d'avoir un mâle par rapport à une femelle était évident quant aux taux de bouchées (CHAPITRE III), il s'est avéré plus difficile à détecter sur d'autres traits. À Anglesea, les jeunes mères avaient moins de probabilité d'avoir un jeune qui atteigne le stade 'LPY' après avoir eu un fils qu'une fille (CHAPITRE II). Toutefois, des résultats contraires à nos attentes ont été trouvés, du moins au premier abord, sur la croissance et le succès reproducteur subséquent. Ainsi, les femelles qui avaient eu une fille perdaient davantage de masse (CHAPITRE I) et avaient généralement une probabilité moindre de produire un jeune qui atteigne le stade 'LPY' ou qui soit sevré par la suite (CHAPITRE II). En revanche, l'intervalle de naissance n'était pas différent suivant le sexe du jeune alors qu'il était fortement affecté par le coût de la reproduction démontré grâce à la manipulation, invoquant une autre explication qu'un coût supérieur des filles par rapport aux fils. En effet, les femelles qui étaient en mauvaise condition corporelle gagnaient de la masse quand elles produisaient une fille, mais pas un fils (CHAPITRE I). De surcroît, les jeunes mères avaient moins de chances de sevrer un jeune à l'événement de reproduction suivant si elles avaient eu un fils plutôt qu'une fille, et le succès reproducteur des mères des fils n'était plus différent de celui des mères des filles dans les années plus difficiles (CHAPITRE II). Enfin, les mères des fils augmentaient la quantité de nourriture ingérée si elles avaient sevré un jeune l'année précédente, mais les mères des filles la diminuaient. Ces différents résultats suggéraient fortement qu'un ajustement du sexe-ratio était utilisé quand les ressources individuelles ou environnementales contraignaient davantage la reproduction. En conclusion, pour limiter le décalage entre les besoins énergétiques et la disponibilité en nourriture, les femelles chez le kangourou gris de l'Est pourraient modifier l'allocation de leurs ressources à la reproduction en reportant la prochaine mise bas et en produisant un jeune du sexe le moins coûteux en accord avec les contraintes individuelles et environnementales. Ces résultats soulignent l'importance d'études avec un suivi individuel sur plusieurs années afin de pouvoir comprendre la variabilité des stratégies de reproduction et leurs conséquences sur la dynamique des populations. // Abstract : Reproduction in living beings, particularly in female mammals that produce milk, is costly, potentially involving trade-offs with life-history traits if resources are limited and an increase in foraging effort. Individual differences may, however, hide the negative effects of this cost on life-history traits. I used two powerful and complementary approaches, to deal with individual heterogeneity: experimental manipulation of reproductive effort and statistical control of individual effect. Using both approaches, I investigated the effect of presence, size and sex of young on growth, subsequent reproduction and individual foraging behaviours of females. I used data of tagged free-ranging eastern grey kangaroos (Macropus giganteus) collected over six years at five study sites in Victoria, Australia. There was a clear cost of reproduction. Reproductive effort decreased mass gain and limb growth for inter-capture intervals greater than two years. Over two successive reproductive events, mass gain and arm growth were reduced but leg growth was independent of reproductive effort (CHAPTER II).In addition, survival to Large Pouch Young ('LPY') stage, about 7 months of age, was higher and birth rate lower in manipulated compared to control females but survival to weaning was not affected (CHAPTER III). CHAPTER IV shows that lactating females cope with current reproductive costs by increasing ivtime spent foraging as well as bite and chewing rates without decreasing vigilance comparedto non lactating ones. Bite rate was also greater for females that weaned a young at the previous reproductive event. My study supports reproductive cost hypothesis while showing substantial individual differences. To limit mismatch between energetic needs and resource availability, females of eastern grey kangaroo could modify resource allocation to reproduction by delaying birth date of subsequent young and producing the less costly sex according to individual and environmental constrains. My thesis shows the importance of experimental approach and individual monitoring over multiple years to understand the diversity of reproductive strategies and their consequences in evolutionary ecology and population dynamic.