The Development of Public Finances and Role of Fiscal Constraints in a Monetary Union: Example eurozone

This thesis is about the development of public debt and deficit in the eurozone, which has been in the center of attention for much of the new millennium. The debt-to-GDP and deficit-to-GDP ratios have changed significantly during the period of the European monetary integration, with sharp increases in the levels since the beginning of the financial crisis. We view the levels both before and after the establishment of the European Central Bank. The subject is complemented by a study of the restrictions on fiscal policy in the eurozone. The thesis begins with a review of the most central agreements in the Economic and Monetary Union, namely the Maastricht Treaty, the Stability and Growth Pact and the Fiscal Compact. We study the instructions and requirements provided by these contracts, with the emphasis being on the debt and deficit values. Furthermore, we view two theories that aim to provide us with information, whether the fiscal restrictions are useful or not. The second and empirical part consists of review on the debt and deficit levels in practice. We take a close look on the values for each of the currency union members. The third and last part summarizes the findings, and analyzes the reasons behind the changes. The result of the thesis is, that even though the levels of public debt and deficit have worsened since the beginning of the financial crisis, tight rules on fiscal policy might not be the best possible solution. Private sector has played a crucial part in the increase of the debt levels, and tight rules have their impact on the long awaited economic growth in the eurozone. It is obvious, though, that some form of fiscal guidelines with scientific ground are needed in order to avoid excessive and harmful debt and deficit levels. The main task is to make these guidelines a more essential part of the fiscal policy in each of the member countries.

New constraints on European glacial freshwater releases to the North Atlantic Ocean

During the late Quaternary, both external and internal forcings have driven major climatic shifts from glacial to interglacial conditions. Nonlinear climatic steps characterized the transitions leading to these extrema, with intermediate excursions particularly well expressed in the dynamics of the Northern Hemisphere cryosphere. Here we document the impact of these dynamics on the north-eastern North Atlantic Ocean, focussing on the 35-10 ka interval. Sea-surface salinities have been reconstructed quantitatively based on two independent methods from core MD95-2002, recovered from the northern Bay of Biscay adjacent to the axis of the Manche paleoriver outlet and thus in connection with proximal European ice sheets and glaciers. Quantitative reconstructions deriving from dinocyst and planktonic foraminiferal analyses have been combined within a robust chronology to assess the amplitude and timing of hydrological changes in this region. Our study evidences strong pulsed freshwater discharges which may have impacted the North Atlantic Meridional Overturning Circulation.

The multistage crystallization of zircon in calc-alkaline granitoids : U-Pb age constraints on the timing of Variscan tectonic activity in SW Iberia

CL imaging and U–Th–Pb data for a population of zircons from two of the Évora Massif granitoids (Ossa-Morena Zone, SW Iberia) show that both calc-alkaline granitoids have zircon populations dominated by grains with cores and rims either showing or not showing differences in Th/U ratio, and having ages in the range ca. 350–335 Ma (Early Carboniferous). Multistage crystallization of zircon is revealed in two main growth stages (ca. 344–342 Ma and ca. 336–335 Ma), well represented by morphologically complex zircons with cores and rims with different ages and different Th/U ratios that can be explained by: (1) crystallization from melts with different compositions (felsic peraluminous to felsic-intermediate metaluminous; 0.001 Th/U ratio < 0.5) and (2) transient temperature fluctuations in a system where anatectic felsic melts periodically underwent injection of more mafic magmas at higher temperatures. The two studied calc-alkaline granitoids do not include inherited zircons (pre-Carboniferous), probably because they were formed at the highest grade of metamorphism (T 837 °C; granulite facies) and/or because they were derived from inheritance-poor felsic and mafic rocks from a previous cycle, as suggested by the internal structures of zircon cores. These Variscan magmatic rocks with crystallization ages estimated at ca. 336–335 Ma are spatially and temporally related to high-temperature metamorphism, anatexis, processes of interaction between crustal- and mantle-derived magmas and intra-orogenic extension that acted in SW Iberia during the Early Carboniferous.

Ecoviability for small-scale fisheries in the context of food security constraints

This paper applies a stochastic viability approach to a tropical small-scale fishery, offering a theoretical and empirical example of ecosystem-based fishery management approach that accounts for food security. The model integrates multi-species, multi-fleet and uncertainty as well as profitability, food production, and demographic growth. It is calibrated over the period 2006–2010 using monthly catch and effort data from the French Guiana's coastal fishery, involving thirteen species and four fleets. Using projections at the horizon 2040, different management strategies and scenarios are compared from a viability viewpoint, thus accounting for biodiversity preservation, fleet profitability and food security. The analysis shows that under certain conditions, viable options can be identified which allow fishing intensity and production to be increased to respond to food security requirements but with minimum impacts on the marine resources.

WorldFish Center report on the opportunities and constraints to improved fisheries exploitation and management in the Maringa – Lopori – Wamba landscape

The WorldFish Center was contracted by Africa Wildlife Foundation to conduct a preliminary survey of the role of fisheries in livelihoods, and opportunities and constraints to improved fisheries exploitation and management, in the Maringa-Lopori-Wamba Landscape. In May 2007, a three person WorldFish Center team, supported by AWF staff, visited the landscape to explore how the fishery operates to meet local needs and identify scope for interventions that might improve fisheries livelihood opportunities without undermining its sustainability. It is clear that although fishing is important for both income and subsistence in the areas visited, profits are nonetheless modest and somewhat unpredictable. Moreover, fisherfolk should not be considered a homogeneous group: there are different sub-groups, using different gears and skills, involving women and men in both fishing and post-harvest activities, groups who are more or less dependent on farming, and who fish, on balance, more either for cash or subsistence needs. Thus the findings here need to be set within this context of different sub-groups, fishing for generally very modest remuneration, with the latter subject to considerable variability and uncertainty.

Biomechanical constraints remain major risk factors for low back pain. Results from a prospective cohort study in French male employees

International audience

Thinning of the Goban Spur continental margin and formation of early oceanic crust: Constraints from forward modelling and inversion of marine magnetic anomalies

The deep seismic reflection profile Western Approaches Margin (WAM) cuts across the Goban Spur continental margin, located southwest of Ireland. This non-volcanic margin is characterized by a few tilted blocks parallel to the margin. A volcanic sill has been emplaced on the westernmost tilted block. The shape of the eastern part of this sill is known from seismic data, but neither seismic nor gravity data allow a precise determination of the extent and shape of the volcanic body at depth. Forward modelling and inversion of magnetic data constrain the shape of this volcanic sill and the location of the ocean-continent transition. The volcanic body thickens towards the ocean, and seems to be in direct contact with the oceanic crust. In the contact zone, the volcanic body and the oceanic magnetic layer display approximately the same thickness. The oceanic magnetic layer is anomalously thick immediately west of the volcanic body, and gradually thins to reach more typical values 40 km further to the west. The volcanic sill would therefore represent the very first formation of oceanic crust, just before or at the continental break-up. The ocean-continent transition is limited to a zone 15 km wide. The continental magnetic layer seems to thin gradually oceanwards, as does the continental crust, but no simple relation is observed between their respective thinnings.

CONSTRAINTS ON THE LITHOSPHERIC STRUCTURE OF MID OCEAN RIDGES FROM OCEANIC CORE COMPLEX MORPHOLOGY

The Mid-oceanic ridge system is a feature unique to Earth. It is one of the fundamental components of plate tectonics and reflects interior processes of mantle convection within the Earth. The thermal structure beneath the mid-ocean ridges has been the subject of several modeling studies. It is expected that the elastic thickness of the lithosphere is larger near the transform faults that bound mid-ocean ridge segments. Oceanic core complexes (OCCs), which are generally thought to result from long-lived fault slip and elastic flexure, have a shape that is sensitive to elastic thickness. By modeling the shape of OCCs emplaced along a ridge segment, it is possible to constraint elastic thickness and therefore the thermal structure of the plate and how it varies along-axis. This thesis builds upon previous studies that utilize thin plate flexure to reproduce the shape of OCCs. I compare OCC shape to a suite of models in which elastic thickness, fault dip, fault heave, crustal thickness, and axial infill are systematically varied. Using a grid search, I constrain the parameters that best reproduce the bathymetry and/or the slope of ten candidate OCCs identified along the 12°—15°N segment of the Mid-Atlantic Ridge. The lithospheric elastic thicknesses that explains these OCCs is thinner than previous investigators suggested and the fault planes dip more shallowly in the subsurface, although at an angle compatible with Anderson’s theory of faulting. No relationships between model parameters and an oceanic core complexes location within a segment are identified with the exception that the OCCs located less than 20km from a transform fault have slightly larger elastic thickness than OCCs in the middle of the ridge segment.

Dinocyst assemblage constraints on oceanographic and atmospheric processes in the eastern equatorial Atlantic over the last 44 kyr

A new 44 kyr long record of dinoflagellate (phytoplanktonic organisms) cysts (dinocysts) is presented from a marine sediment core collected on the Congolese margin with the aim of reconstructing past hydrological changes in the equatorial eastern Atlantic Ocean since Marine Isotopic Stage (MIS) 3. Our high-resolution dinocyst record indicates that significant temperature and moisture variations occurred across the glacial period, the last deglaciation and the Holocene. The use of specific dinocyst taxa, indicative of fluvial, upwelling and Benguela Current past environments for instance, provides insights into the main forcing mechanisms controlling palaeohydrological changes on orbital timescales. In particular, we are able, for the last 44 kyr, to correlate fluvial-sensitive taxa to monsoonal mechanisms related to precession minima–obliquity maxima combinations. While upwelling mechanisms appear as the main drivers for dinoflagellate productivity during MIS 2, dissolved nutrient-enriched Congo River inputs to the ocean also played a significant role in promoting dinoflagellate productivity between approximately 15.5 and 5 ka BP. Finally, this high-resolution dinocyst study permits us to precisely investigate the suborbital timing of the last glacial–interglacial termination, including an atypical warm and wet oceanic LGM signature, northern high-latitude abrupt climate change impacts in the equatorial eastern Atlantic, as well as a two-step decrease in moisture conditions during the Holocene at around 7–6 and 4–3.5 ka BP.

Motion Planning and Controls with Safety and Temporal Constraints

Motion planning, or trajectory planning, commonly refers to a process of converting high-level task specifications into low-level control commands that can be executed on the system of interest. For different applications, the system will be different. It can be an autonomous vehicle, an Unmanned Aerial Vehicle(UAV), a humanoid robot, or an industrial robotic arm. As human machine interaction is essential in many of these systems, safety is fundamental and crucial. Many of the applications also involve performing a task in an optimal manner within a given time constraint. Therefore, in this thesis, we focus on two aspects of the motion planning problem. One is the verification and synthesis of the safe controls for autonomous ground and air vehicles in collision avoidance scenarios. The other part focuses on the high-level planning for the autonomous vehicles with the timed temporal constraints. In the first aspect of our work, we first propose a verification method to prove the safety and robustness of a path planner and the path following controls based on reachable sets. We demonstrate the method on quadrotor and automobile applications. Secondly, we propose a reachable set based collision avoidance algorithm for UAVs. Instead of the traditional approaches of collision avoidance between trajectories, we propose a collision avoidance scheme based on reachable sets and tubes. We then formulate the problem as a convex optimization problem seeking control set design for the aircraft to avoid collision. We apply our approach to collision avoidance scenarios of quadrotors and fixed-wing aircraft. In the second aspect of our work, we address the high level planning problems with timed temporal logic constraints. Firstly, we present an optimization based method for path planning of a mobile robot subject to timed temporal constraints, in a dynamic environment. Temporal logic (TL) can address very complex task specifications such as safety, coverage, motion sequencing etc. We use metric temporal logic (MTL) to encode the task specifications with timing constraints. We then translate the MTL formulae into mixed integer linear constraints and solve the associated optimization problem using a mixed integer linear program solver. We have applied our approach on several case studies in complex dynamical environments subjected to timed temporal specifications. Secondly, we also present a timed automaton based method for planning under the given timed temporal logic specifications. We use metric interval temporal logic (MITL), a member of the MTL family, to represent the task specification, and provide a constructive way to generate a timed automaton and methods to look for accepting runs on the automaton to find an optimal motion (or path) sequence for the robot to complete the task.

Constraints to the efficacy of risk management process in entrepreneurial companies

This paper highlights potential factors that affect the degree of efficacy of a formal risk management framework in entrepreneurial organisations. The understanding of entrepreneur’s self-schemas, entrepreneurial organisational culture and working environment is crucial to evaluate the efficacy of a risk management process. This research pointed out two main issues: i) the entrepreneurial decision making process with presence of biases and heuristics in judgement under uncertainty; and ii) the entrepreneurial organisational context that might create constraints to the implementation of a risk management framework.

Essays on Financial Constraints, R&D Investments, and Competition

This dissertation consists of two chapters of theoretical studies that investigate the effect of financial constraints and market competition on research and development (R&D) investments. In the first chapter, I explore the impact of financial constraints on two different types of R&D investments. In the second chapter, I examine the impact of market competition on the relationship between financial constraints and R&D investments. In the first chapter, I develop a dynamic monopoly model to study a firm’s R&D strategy. Contrary to intuition, I show that a financially constrained firm may invest more aggressively in R&D projects than an unconstrained firm. Financial constraints introduce a risk that a firm may run out of money before its project bears fruit, which leads to involuntary termination on an otherwise positive-NPV project. For a company that relies on cash flow from assets in place to keep its R&D project alive, early success can be relatively important. I find that when the discovery process can be expedited by heavier investment (“accelerable” projects), a financially constrained company may find it optimal to “over”-invest in order to raise the probability of project survival. The over-investment will not happen if the project is only “scalable” (investment scales up payoffs). The model generates several testable implications regarding over-investment and project values. In the second chapter, I study the effects of competition on R&D investments in a duopoly framework. Using a homogeneous duopoly model where two unconstrained firms compete head to head in an R&D race, I find that competition has no effect on R&D investment if the project is not accelerable, and the competing firms are not constrained. In a heterogeneous duopoly model where a financially constrained firm competes against an unconstrained firm, I discover interesting strategic interactions that lead to preemption by the constrained firm in equilibrium. The unconstrained competitor responds to its constrained rival’s investment in an inverted-U shape fashion. When the constrained competitor has high cash flow risk, it accelerates the innovation in equilibrium, while the unconstrained firm invests less aggressively and waits for its rival to quit the race due to shortage of funds.

Household portfolio allocation, risk attitudes and credit constraints : evidence from the eurozone

Mestrado em Economia Monetária e Financeira