9,469 research outputs found
MORPH: A Reference Architecture for Configuration and Behaviour Self-Adaptation
An architectural approach to self-adaptive systems involves runtime change of
system configuration (i.e., the system's components, their bindings and
operational parameters) and behaviour update (i.e., component orchestration).
Thus, dynamic reconfiguration and discrete event control theory are at the
heart of architectural adaptation. Although controlling configuration and
behaviour at runtime has been discussed and applied to architectural
adaptation, architectures for self-adaptive systems often compound these two
aspects reducing the potential for adaptability. In this paper we propose a
reference architecture that allows for coordinated yet transparent and
independent adaptation of system configuration and behaviour
Reconfiguration of Distributed Information Fusion System ? A case study
Information Fusion Systems are now widely used in different fusion contexts,
like scientific processing, sensor networks, video and image processing. One of
the current trends in this area is to cope with distributed systems. In this
context, we have defined and implemented a Dynamic Distributed Information
Fusion System runtime model. It allows us to cope with dynamic execution
supports while trying to maintain the functionalities of a given Dynamic
Distributed Information Fusion System. The paper presents our system, the
reconfiguration problems we are faced with and our solutions.Comment: 6 pages - Preprint versio
Automatic Reconfiguration of Untimed Discrete-Event Systems
This work introduces a general formulation of the reconfiguration problem for
untimed discrete-event systems (DES), which can be treated directly by
supervisory control theory (SCT). To model the reconfiguration requirements we
introduce the concept of reconfiguration specification (RS); here
reconfiguration events (RE) are introduced to force a transition from one
system configuration to another. Standard SCT synthesis is employed to obtain a
reconfiguration supervisor (RSUP) in which designated states serve as the
source states for RE. The reconfiguration problem itself is formulated as that
of establishing guaranteed finite reachability of a desired RE source state in
RSUP from the current state in RSUP at which a change in configuration is
commanded by an external user. The solvability (or otherwise) of this
reachability problem is established by backtracking as in standard dynamic
programming.Comment: 2017 14th International Conference on Electrical Engineering,
Computing Science and Automatic Control (CCE
Two Cases of Study for Control Reconfiguration of Discrete Event Systems (DES)
International audienceIn this paper, we propose two cases of study for control reconfiguration of Discrete Event Systems. The main contributions are based on a safe centralized and distributed control synthesis founded on timed properties. In fact, if a sensor fault is detected, the controller of the normal behavior is reconfigured to a timed controller where the timed information replaces the information lost on the faulty sensor. Finally, we apply our contribution to a manufacturing system to illustrate our results and compare between the two frameworks
System configuration and executive requirements specifications for reusable shuttle and space station/base
System configuration and executive requirements specifications for reusable shuttle and space station/bas
Dynamic update of discrete event controllers
Discrete event controllers are at the heart of many software systems that require continuous operation. Changing these controllers at runtime to cope with changes in its execution environment or system requirements change is a challenging open problem. In this paper we address the problem of dynamic update of controllers in reactive systems. We present a general approach to specifying correctness criteria for dynamic update and a technique for automatically computing a controller that handles the transition from the old to the new specification, assuring that the system will reach a state in which such a transition can correctly occur and in which the underlying system architecture can reconfigure. Our solution uses discrete event controller synthesis to automatically build a controller that guarantees both progress towards update and safe update
Distributed Predictive Control for MVDC Shipboard Power System Management
Shipboard Power System (SPS) is known as an independent controlled small electric network powered by the distributed onboard generation system. Since many electric components are tightly coupled in a small space and the system is not supported with a relatively stronger grid, SPS is more susceptible to unexpected disturbances and physical damages compared to conventional terrestrial power systems. Among different distribution configurations, power-electronic based DC distribution is considered the trending technology for the next-generation U.S. Navy fleet design to replace the conventional AC-based distribution. This research presents appropriate control management frameworks to improve the Medium-Voltage DC (MVDC) shipboard power system performance. Model Predictive Control (MPC) is an advanced model-based approach which uses the system model to predict the future output states and generates an optimal control sequence over the prediction horizon. In this research, at first, a centralized MPC is developed for a nonlinear MVDC SPS when a high-power pulsed load exists in the system. The closed-loop stability analysis is considered in the MPC optimization problem. A comparison is presented for different cases of load prediction for MPC, namely, no prediction, perfect prediction, and Autoregressive Integrated Moving Average (ARIMA) prediction. Another centralized MPC controller is also designed to address the reconfiguration problem of the MVDC system in abnormal conditions. The reconfiguration goal is to maximize the power delivered to the loads with respect to power balance, generation limits and load priorities. Moreover, a distributed control structure is proposed for a nonlinear MVDC SPS to develop a scalable power management architecture. In this framework, each subsystem is controlled by a local MPC using its state variables, parameters and interaction variables from other subsystems communicated through a coordinator. The Goal Coordination principle is used to manage interactions between subsystems. The developed distributed control structure brings out several significant advantages including less computational overhead, higher flexibility and a good error tolerance behavior as well as a good overall system performance. To demonstrate the efficiency of the proposed approach, a performance analysis is accomplished by comparing centralized and distributed control of global and partitioned MVDC models for two cases of continuous and discretized control inputs
Reconfigurable Timed Discrete-Event Systems
In this paper, we present the first general solution to the automatic
reconfiguration problem of timed discrete-event systems. We extend the
recursive forcible backtracking approach which had been already solved the
automatic reconfiguration problem of untimed discrete-event systems. In
particular, we first solve the timed centralized reconfiguration problem using
a specific timed eligibility set. Then, we study the identity between the
solutions to an arbitrary timed centralized reconfiguration problem and its
corresponding decentralized version. It turns out that the solutions to both
cases are identical to each other. So, the solution obtained by the proposed
theory is interestingly invariant to systematic distributions.Comment: 2020 24th International Conference on System Theory, Control and
Computing (ICSTCC
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