The thesis presents different control design approaches for stabilizing networks of quasi-linear hyperbolic partial differential equations. These equations are usually conservative, which gives them interesting properties to design stabilizing control laws.
Two main design approaches are developed: a methodology based on entropies and Lyapunov functions and a methodology based on the Riemann invariants. The stability theorems are illustrated using numerical simulations. Two practical applications of these methodologies are presented. Network of navigation channels are modelled using the Saint-Venant equation (also known as the Shallow Water Equations). The stabilization problem of such system has an industrial importance in order to satisfy the navigation constraints and to optimize the production of electricity in hydroelectric plants, usually located at each hydraulic gate. A second application deals with the regulation of water waves in moving tanks. This problem is also modelled by a modified version of the shallow water equations and appears in a number industrial fields which deal with liquid moving parts.
1 INTRODUCTION 1
1.1 Problem: heterogeneity . . . . . . . . . . . . . . . . 1
1.2 Methodology: complementarity . . . . . . . . . . . 3
1.3 Results . . . . . . . . . . . . . . . . . . . . . . . . . 5
2 ENDOGENOUS HETEROGENEITY IN STRATEGICMODELS: SYMMETRY BREAKING VIA STRATEGIC SUBSTITUTES AND NON-CONCAVITIES 11
2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . 11
2.2 Setup . . . . . . . . . . . . . . . . . . . . . . . . . . 21
2.3 Endogenous heterogeneity with strategic substitutes 22
2.3.1 The results . . . . . . . . . . . . . . . . . . 24
2.3.2 Applications . . . . . . . . . . . . . . . . . . 28
2.3.2.1 R&D investment . . . . . . . . . . 28
2.3.2.2 Provision of information . . . . . . 32
2.4 Endogenous heterogeneity without monotonic best replies . . . . . . . . . . . . . . . . . . . . . . . . . 34
2.4.1 The results . . . . . . . . . . . . . . . . . . 36
2.4.2 Applications: quality investment . . . . . . . 41
2.5 Convex Payo¤s . . . . . . . . . . . . . . . . . . . . 43
2.5.1 Applications . . . . . . . . . . . . . . . . . . 45
2.6 Extensions . . . . . . . . . . . . . . . . . . . . . . . 46
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2.7 Conclusion . . . . . . . . . . . . . . . . . . . . . . . 48
2.8 Appendix . . . . . . . . . . . . . . . . . . . . . . . 50
2.8.1 Summary of supermodular/submodular games 50
2.8.2 Proofs of Section 2.3 . . . . . . . . . . . . . 52
2.8.3 Proofs of Section 2.4 . . . . . . . . . . . . . 61
2.8.4 Proofs of Section 2.6 . . . . . . . . . . . . . 63
3 SYMMETRIC VERSUS ASYMMETRIC EQUILIBRIA IN SYMMETRIC N PLAYER SUPERMODULAR GAMES 71
3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . 71
3.2 Lattice-theoretic preliminaries . . . . . . . . . . . . 75
3.3 Symmetric versus asymmetric PSNE . . . . . . . . 78
3.4 On the scope of our results . . . . . . . . . . . . . . 91
3.4.1 Submodular games . . . . . . . . . . . . . . 92
3.4.2 Games with quasi-convex payo¤s . . . . . . 94
4 MARKET TRANSPARENCY AND BERTRAND COMPETITION 101
4.1 Introduction . . . . . . . . . . . . . . . . . . . . . . 101
4.2 Setup and de.nitions . . . . . . . . . . . . . . . . . 105
4.2.1 General setup . . . . . . . . . . . . . . 105
4.2.2 Useful de.nitions and results . . . . . . . . . 107
4.3 E¤ect of transparency on prices . . . . . . . . . . . 109
4.3.1 Strategic complementarities . . . . . . . . . 109
4.3.2 Strategic substitutes . . . . . . . . . . . . . 112
4.3.2.1 Symmetric games . . . . . . . . . . 113
4.3.2.2 Asymmetric games . . . . . . . . . 114
4.4 E¤ects of transparency on pro.ts . . . . . . . . . . 117
4.5 Linear example . . . . . . . . . . . . . . . . . . . . 119
4.6 Conclusions . . . . . . . . . . . . . . . . . . . . . . 122
5 STRATEGIC SUBSTITUTES AND COMPLEMENTS IN COURNOT OLIGOPOLYWITH PRODUCT DIFFERENTIATION 127
5.1 Introduction . . . . . . . . . . . . . . . . . . . . . . 127
5.2 Supermodular games . . . . . . . . . . . . . . . . . 129
5.3 Conditions and examples . . . . . . . . . . . . . . . 133
5.4 Discussion . . . . . . . . . . . . . . . . . . . . . . . 142
5.5 Appendix . . . . . . . . . . . . . . . . . . . . . . . 143