Self-Tuning of Software Systems Through Goal-based Feedback Loop Control

Author(s):  
Xin Peng ◽  
Bihuan Chen ◽  
Yijun Yu ◽  
Wenyun Zhao
Author(s):  
Kriss Ravetto-Biagioli

We are confronted with a new type of uncanny experience, an uncanny evoked by parallel processing, aggregate data, and cloud-computing. The digital uncanny does not erase the uncanny feeling we experience as déjà vu or when confronted with robots that are too lifelike. Today’s uncanny refers to how nonhuman devices (surveillance technologies, algorithms, feedback, and data flows) anticipate human gestures, emotions, actions, and interactions, intimating we are machines and our behavior is predicable because we are machinic. It adds another dimension to those feelings we get when we question whether our responses are subjective or automated—automated as in reducing one’s subjectivity to patterns of data and using those patterns to present objects or ideas that would then elicit one’s genuinely subjective—yet effectively preset—response. This anticipation of our responses is a feedback loop we have produced by designing software that studies our traces, inputs, and moves. Digital Uncanny explores how digital technologies, particularly software systems working through massive amounts of data, are transforming the meaning of the uncanny that Freud tied to a return of repressed memories, desires, and experiences to their anticipation. Through a close reading of interactive and experimental art works of Rafael Lozano-Hemmer, Bill Viola, Simon Biggs, Sue Hawksley, and Garth Paine, this book is designed to explore how the digital uncanny unsettles and estranges concepts of “self,” “affect,” “feedback,” and “aesthetic experience,” forcing us to reflect on our relationship with computational media and our relationship to others and our experience of the world.


Measurement ◽  
2019 ◽  
Vol 134 ◽  
pp. 586-594 ◽  
Author(s):  
Ján Cárach ◽  
Sergej Hloch ◽  
Jana Petrů ◽  
Miroslav Müller ◽  
Monika Hromasová ◽  
...  

2009 ◽  
pp. 3215-3241 ◽  
Author(s):  
João Pedro Sousa ◽  
Bradley Schmerl ◽  
Peter Steenkiste ◽  
David Garlan

This chapter introduces a new way of thinking about software systems for supporting the activities of end-users. In this approach, models of user activities are promoted to first class entities, and software systems are assembled and configured dynamically based on activity models. This constitutes a fundamental change of perspective over traditional applications; activities take the main stage and may be long-lived, whereas the agents that carry them out are plentiful and interchangeable. The core of the chapter describes a closed-loop control design that enables activity-oriented systems to become self-aware and self-configurable, and to adapt to dynamic changes both in the requirements of user activities and in the environment resources. The chapter discusses how that design addresses challenges such as user mobility, resolving conflicts in accessing scarce resources, and robustness in the broad sense of responding adequately to user expectations, even in unpredictable situations, such as random failures, erroneous user input, and continuously changing resources. The chapter further summarizes challenges and ongoing work related to managing activities where humans and automated agents collaborate, human-computer interactions for managing activities, and privacy and security aspects.


1995 ◽  
Vol 7 (1) ◽  
pp. 63-68 ◽  
Author(s):  
Junji Fukumi ◽  
◽  
Takuya Kamano ◽  
Takayuki Suzuki ◽  
Yu Kataoka ◽  
...  

This paper considers the use of a self-tuning fuzzy controller for a positioning system with a progressive wavetype ultrasonic motor. The system consists of a feedback loop with a conventional controller and a self tuning fuzzy controller. The objective of the self tuning fuzzy controller is to restrain the adverse effect of nonlinear characteristics of the motor and to improve the tracking performance. The self-tuning fuzzy controller is functionally divided into two layers. The fuzzy rules are automatically adjusted by a tuning algorithm so that the tracking error is minimized in the upper layer. In lower layer, the output signal of the self tuning fuzzy controller is obtained by fuzzy reasoning procedure. After the tuning process is completed, the tracking error almost converges to zero, and the ultrasonic motor is no longer controlled by the fixed gain feedback controller but by the self-tuning fuzzy controller. The effectiveness of the proposed self-tuning fuzzy controller is demonstrated by an experiment.


Author(s):  
A. J. Riley ◽  
S. Park ◽  
A. P. Dowling ◽  
S. Evesque ◽  
A. M. Annaswamy

Active control of pressure oscillations has been successfully applied to a lean premixed prevapourised (LPP) combustion rig operating at atmospheric conditions. The design of the rig is based on the primary stage of the Rolls-Royce RB211-DLE industrial gas turbine. Control was achieved by modulating the fuel flow rate in response to a measured pressure signal. The feedback control is an adaptive, model-based self-tuning regulator (STR), which only requires the total time delay between actuation and response to achieve control. The STR algorithm achieves a reduction of up to 30 dB on the primary instability frequency. This performance was an improvement of 5–15 dB over an empirical control strategy (simple time-delay controller) specifically tuned to the same operating point. Initial robustness studies have shown that the STR retains control for a 20% change in frequency and a 23% change in air mass flow rate.


Author(s):  
Alberto Barchielli ◽  
Matteo Gregoratti

In this article, we reconsider a version of quantum trajectory theory based on the stochastic Schrödinger equation with stochastic coefficients, which was mathematically introduced in the 1990s, and we develop it in order to describe the non-Markovian evolution of a quantum system continuously measured and controlled, thanks to a measurement-based feedback. Indeed, realistic descriptions of a feedback loop have to include delay and thus need a non-Markovian theory. The theory allows us to put together non-Markovian evolutions and measurements in continuous time, in agreement with the modern axiomatic formulation of quantum mechanics. To illustrate the possibilities of such a theory, we apply it to a two-level atom stimulated by a laser. We introduce closed loop control too, via the stimulating laser, with the aim of enhancing the ‘squeezing’ of the emitted light, or other typical quantum properties. Note that here we change the point of view with respect to the usual applications of control theory. In our model, the ‘system’ is the two-level atom, but we do not want to control its state, to bring the atom to a final target state. Our aim is to control the ‘Mandel Q -parameter’ and the spectrum of the emitted light; in particular, the spectrum is not a property at a single time, but involves a long interval of times (a Fourier transform of the autocorrelation function of the observed output is needed).


2012 ◽  
Vol 516-517 ◽  
pp. 660-664
Author(s):  
Da Ye Ding ◽  
Shao Juan Yu ◽  
Chen Li

The development of ultra-supercritical units is feasible choice of energy utilization ratio in China, its stability and economy rely on control system of turbine mightily. The control system of 600MW turbine is widely used currently, according to the non-linear time-varying excitation control system of turbine speed, the speed of turbine is employed as the feedback variable, a controller combined with a PID feedback loop control system is designed, analyzed and studied respectively from theory and emulation. The simulation results shows that PID feedback control has good effects in inhibiting interference andstabilizing system. Put forward strategy that can control the speed of turbine on this basis in order to achieve the goal of turbine’s fast tracking and stability control.


Author(s):  
Jan Awrejcewicz ◽  
Krzysztof Tomczak

Abstract In this paper an attention is focused on stabilisation improvement of periodic orbits of a one- and two-degree-of-freedom nonautonomous vibro-impact systems. This approach, among others, includes two problems. 1. A possibility of a sufficient stability improvement of the considered vibro-impact periodic motion using a feedback loop control is presented. 2. An original analytical averaging technique applied to a one-degree-of-freedom system is demonstrated. It enables to predict the efficient delay loop coefficients in order to achieve the desired stabilisation. In addition, an efficient delay loop control applied to two-degree-of-freedom system is proposed and illustrated.


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