Abstract
The main purpose of necessary conditions of optimality (NCO) is to identify a 'small' set of candidates to minimizers among the overall set of admissible solutions. However, for certain optimal control problems with state constraints, it might happen that the set of all admissible solutions coincides with the set of candidates satisfying the NCO. This phenomenon is known as the degeneracy phenomenon and there has been some literature proposing stronger forms of NCO that can be informative in such cases: The so-called nondegenerate NCO. The nondegenerate NCO proposed here are valid under a different set of hypothesis and under a constraint qualification of an integral-type that, in relation to some previous literature, is easier to verify. © 2007 EUCA.

Abstract
Nowadays, the large penetration of wind power generation poses new challenges for dynamic voltage stability analysis of an electric power system. The practical importance of dynamic voltage stability analysis is to help in designing and selecting counter-measures in order to avoid voltage collapse and enhance system stability. The impact of wind integration on reactive reserve requirements is a current area of interest for renewable integration studies and power system operators. In this paper is studied a new wind power plant model with reactive power management. The active power and the frequency management are taken into account too. The developed model can be used to represent, in a simplified way, an entire wind farm in order to simulate the dynamic voltage stability of the system, whatever the technology involved in the wind turbine. The system is completely modelled by a single dynamic converter model with appropriate control loops intended to reproduce the overall response of a wind farm for different grid events, such as faults or voltage and reactive power management at the point of common coupling.

Abstract
Renewable energy sources are one key enabler to decrease greenhouse gas emissions and to cope with the anthropogenic climate change. Their intermittent behavior and limited storage capabilities present a new challenge to power system operators to maintain power quality and reliability. Additional technical complexity arises from the large number of small distributed generation units and their allocation within the power system. Market liberalization and changing regulatory framework lead to additional organizational complexity. As a result, the design and operation of the future electric energy system have to be redefined. Sophisticated information and communication architectures, automation concepts, and control approaches are necessary in order to manage the higher complexity of so-called smart grids. This paper provides an overview of the state of the art and recent developments enabling higher intelligence in future smart grids. The integration of renewable sources and storage systems into the power grids is analyzed. Energy management and demand response methods and important automation paradigms and domain standards are also reviewed.

Abstract
This paper presents the results of an indoor localization experiment that uses spread spectrum modulated audio signals. Indoor spaces do not have line-of-sight to global navigation satellite systems and do not have a truly universal localization system to allow mobile devices to localize themselves. Previous approaches focused in using custom made hardware with several types of signals that, even though with good performance, are not feasible to adopt in a wide scale utilization. The proposed approach uses pre-existent off-the-shelf hardware and easy to handle audio signals present in our everyday lives. However, the challenges when using audible and very susceptible to multipath types of signals are many and require validation of the subjacent principles. An experiment in a real indoor environment was conducted to estimate localization while using spread spectrum noise like signals barely perceptible to people. Results demonstrated a 1.3 cm average accuracy in the center area. These and other results demonstrate the possibility of the use of audio signals with all the advantages regarding wide scale dissemination of an indoor localization solution.

Abstract
Manufacturing systems, and specifically Flexible Manufacturing Systems (FMS), face the challenge of accomplish global optimal performance and reactiveness at dynamic manufacturing environments. For this reason, manufacturing control systems must incorporate mechanisms that support dynamic custom-build responses. This paper introduces a framework that includes a governance mechanism in control system architectures that dynamically steers the autonomy of decision-making between predictive and reactive approaches. Results from experiments led in simulation show that it is worth studying in depth a governance mechanism that tailors the structure and/or behaviour of a manufacturing control system and, at the same time, potentiate the reactivity required in manufacturing operations.

Abstract
Procedural systems allow unique modes of authorship and singular aesthetic experiences. As creators and users of these systems, we need to be aware that their aesthetic potential is not solely defined by interaction but that interpretation, and the capacity to understand and simulate the processes taking place within these artefacts is highly significant. This paper argues that although direct interaction is usually the most discernible component in the relationship between ergodic artefacts and their users, ergodicity does not necessarily imply interaction. Non-interactive procedural artefacts may allow the development of ergodic experiences through interpretation, and the probing of the system by its reader through simulations. We try to set the grounds for designing towards virtuosic interpretation, an activity that we may describe as the ergodic experience developed by means of mental simulation through the development of theories of systems.