Hybrid systems in automotive electronics design

Automotive electronic design is certainly one of the most attractive and promising application domains for hybrid system techniques. Some successful hybrid system applications to automotive model development and control algorithm design have already been reported in the literature. However, despite the significant advances achieved in the past few years, hybrid methods are in general still not mature enough for their effective introduction in the automotive industry design processes at large. In this paper, we take a broad view of the development process for embedded control systems in the automotive industry with the purpose of identifying challenges and additional opportunities for hybrid systems. We identify critical steps in the design flow and extract a number of open problems where hybrid system technology might play an important role

Emotions, moods and hyperreality: social media and the stock market during the first phase of COVID-19 pandemic

Purpose: This paper aims to expand the emerging literature on COVID-19 and the financial markets by searching for a relationship between the uncertainty of the first phase of the COVID-19 pandemic experienced through social media and the extreme volatility of the Italian stock market. Design/methodology/approach: The authors analyze the relationship between social media and stock market trends during the first phase of the COVID-19 pandemic through the lens of social theory and Baudrillard's simulacra and hyperreality theory. The authors conducted the data analysis in two phases: the emotional and Granger correlation analysis by using the KPI6 software to analyze 3,275,588 tweets for the predominant emotion on each day and observe its relationship with the stock market. Findings: The research results show a significant Granger causality relation between tweets on a particular day and the closing price of the FTSE MIB during the first phase of the COVID-19 epidemic. The results highlight a strong relationship between social media hyperreality and the real world. The study confirms the role of social media in predicting stock market volatility. Research limitations/implications: The findings have theoretical and practical implications as they reveal the relevance of social media in our society and its relationship with businesses and economies. In an emergency, social media, as an expression of users' feelings and emotions, can generate a state of hyperreality that is strong correlated with reality. Since social media allows users to publish and share messages without any filter and mediation, the hyperreality generated is affected by highly subjective elements. Originality/value: This research is different from the previous ones on the same topic because unlike previous studies, conducted under normal or simulated scenarios, this study is focused on the first phase of an unpredictable and unforeseen emergency event: the COVID-19 pandemic. This research adopts a multidisciplinary approach and integrates previous studies on the economic and financial effects generated by social media by applying well-known theories to a new and unexplored context. The study reveals the significant impact generated by social media on stock markets during a global pandemic

Making big steps in trajectories

We consider the solution of initial value problems within the context of hybrid systems and emphasise the use of high precision approximations (in software for exact real arithmetic). We propose a novel algorithm for the computation of trajectories up to the area where discontinuous jumps appear, applicable for holomorphic flow functions. Examples with a prototypical implementation illustrate that the algorithm might provide results with higher precision than well-known ODE solvers at a similar computation time

Towards Efficient Exact Synthesis for Linear Hybrid Systems

We study the problem of automatically computing the controllable region of a Linear Hybrid Automaton, with respect to a safety objective. We describe the techniques that are needed to effectively and efficiently implement a recently-proposed solution procedure, based on polyhedral abstractions of the state space. Supporting experimental results are presented, based on an implementation of the proposed techniques on top of the tool PHAVer.Comment: In Proceedings GandALF 2011, arXiv:1106.081

Decentralized Variable Structure Tracking for Systems With Time-Domain Dominance

In this paper, we consider the design of tracking controllers for linear MIMO systems described by an input-output model. The presence of known 'weak' interactions among SISO or MIMO subsystems may allow the designer to achieve objectives by using independent controllers of lower complexity than are necessary in general (control decentralization problem). Sufficient conditions for asymptotic tracking employing decentralized variable structure techniques are derived. The condition is shown to be closely related to (and in a sense, a time-domain counterpart of) dominance criteria used in frequency-domain techniques, as they have developed out of Rosenbrock's original diagonal dominance concept. The synthesis of a decentralized variable-structure controller for asymptotic tracking is illustrated for systems obeying some conditions on their nominal relative degrees

Decentralized Variable Structure Tracking for Systems with Time-Domain Dominance

In this paper, we consider the design of tracking controllers for linear MIMO systems described by an input-output model. The presence of known 'weak' interactions among SISO or MIMO subsystems may allow the designer to achieve objectives by using independent controllers of lower complexity than are necessary in general (control decentralization problem). Sufficient conditions for asymptotic tracking employing decentralized variable structure techniques are derived. The condition is shown to be closely related to (and in a sense, a time-domain counterpart of) dominance criteria used in frequency-domain techniques, as they have developed out of Rosenbrock's original diagonal dominance concept. The synthesis of a decentralized variable-structure controller for asymptotic tracking is illustrated for systems obeying some conditions on their nominal relative degrees