There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

/pdf/convex-analysisnoer-san-nojin-zhan-nituite-5dl2rbmoyr.pdf

Convex Analysisの二,三の進展について

Electrical energy storage technologies for stationary applications are reviewed. Particular attention is paid to pumped hydroelectric storage, compressed air energy storage, battery, flow battery, fuel cell, solar fuel, superconducting magnetic energy storage, flywheel, capacitor/supercapacitor, and thermal energy storage. Comparison is made among these technologies in terms of technical characteristics, applications and deployment status.

http://promexico.me/Rubenius/WhitePapers/sdarticle%20(1).pdf

Progress in electrical energy storage system: A critical review

During the past several years, there have been increasing research activities in the field of stability analysis and switching stabilization for switched systems. This paper aims to briefly survey recent results in this field. First, the stability analysis for switched systems is reviewed. We focus on the stability analysis for switched linear systems under arbitrary switching, and we highlight necessary and sufficient conditions for asymptotic stability. After a brief review of the stability analysis under restricted switching and the multiple Lyapunov function theory, the switching stabilization problem is studied, and a variety of switching stabilization methods found in the literature are outlined. Then the switching stabilizability problem is investigated, that is under what condition it is possible to stabilize a switched system by properly designing switching control laws. Note that the switching stabilizability problem has been one of the most elusive problems in the switched systems literature. A necessary and sufficient condition for asymptotic stabilizability of switched linear systems is described here.

Stability and Stabilizability of Switched Linear Systems: A Survey of Recent Results

This paper presents control and coordination algorithms for groups of vehicles. The focus is on autonomous vehicle networks performing distributed sensing tasks where each vehicle plays the role of a mobile tunable sensor. The paper proposes gradient descent algorithms for a class of utility functions which encode optimal coverage and sensing policies. The resulting closed-loop behavior is adaptive, distributed, asynchronous, and verifiably correct.

Coverage control for mobile sensing networks

Recent developments in computer and communication technologies are leading to an increasingly networked and wireless world. This raises new challenging questions in the context of control for cyberphysical systems (CPS), especially when the computation, communication, energy and actuation resources (for control) of the system are limited and/or shared by multiple control tasks. These limitations obstruct the use of classical design techniques for feedback control algorithms and call for new resource-aware control paradigms. These new resource-aware control systems typically have to take both discrete decisions (which task is allowed to use the resource) and continuous decisions (which continuous control input is generated for the task). In this talk two approaches are presented to address this hybrid co-design problem. Both approaches result in control algorithms that exploit real-time measurement information available on the state of the CPS and decide dynamically on the actions to take. This leads to the situation that individual control tasks are no longer executed in classical periodic time-triggered patterns, but in aperiodic patterns with varying inter-execution times. By abandoning the periodic scheduling of control tasks, the aim is to realise better trade-offs between the overall performance of the CPS and the required resource utilisation. The approaches are illustrated by various applications. interesting challenges for the future are discussed as well.

Resource-aware control and dynamic scheduling in CPS

Proceedings of the 15th IFAC World Congress, 2002

In a series of recent papers [4, 6, 8, 9] discontinuous dynamical systems such as networks with ideal diodes, mechanical systems with inelastic stops and feedback systems with relays have been modeled by complementarity systems. In these systems mode changes are described by a relation between nonnegative, complementary variables as depicted in Fig. 1(a). Here we consider systems obtained by approximating this relation with a Lipschitzian characteristic as shown in Fig. 1(b) or Fig. 1(c) and investigate the convergence of the solutions of the approximating system to those of the ideal system as the Lipschitzian characteristic approaches to (non-Lipschitzian) complementarity relation. Our main result stated as Theorem 2.3 below shows that this kind of continuity of the behavior of the approximating systems holds for linear passive complementarity systems for which existence and uniqueness of solutions have been established in [2, 5]. Moreover, we give necessary and suÆcient conditions for a system to be made passive by shifting its poles. It is shown that the same continuity result holds also for systems passi able by pole shifting. Continuity of linear dynamical systems have been studied before in [3, 11]. The treatment in the present paper is close to the framework of [11] in the sense that we also understand continuity as the convergence of the trajectories of the approximating systems to the trajectories of the limit system. Replacing discontinuous characteristics by smooth ones is a common practice in the simulation of discontinuous dynamical systems, see [1, 7] for instance. The results on the continuity of smooth approximations derived in the present paper provides con dence in computations based on the smoothed versions of linear passive and passi able complementarity systems and allows to draw conclusions about the behavior of the smooth approximations by studying the behavior of the idealized system.

Continuity of smooth approximations of complementarity systems

Technological innovation pushes towards the consideration of dynamical systems of a mixed continuous and discrete nature, which are called “hybrid systems.” Hybrid systems arise, for instance, from the combination of an analog continuous-time process and a digital timeasynchronous controller. Many consumer products (cars, micro-wave units, washing machines and so on) are controlled by digital embedded software, rendering the overall process a system with mixed dynamics. Also many physical systems display hybrid behaviour: the description of multi body dynamics depends crucially on the presence or absence of a contact, models of friction phenomena distinguish between slip and stick phases and electrical circuits contain switching elements like diodes that can be blocking (open circuit) or conducting (short circuit).

http://www.dct.tue.nl/New/Heemels/Conferences/HeeCam_eindhoven_00.pdf

Wpmh Maurice Heemels

Papers

Resource-aware control and dynamic scheduling in CPS

Proceedings of the 15th IFAC World Congress, 2002

Continuity of smooth approximations of complementarity systems

Linear complementarity systems: modelling power and well-posedness

Proc. of the 39th IEEE Conference on Decision and Control