8 research outputs found
Limited Lookahead Policies for Robust Supervisory Control of Discrete Event Systems
In this thesis, Limited Lookahead Policies (LLP) have been developed for Robust Nonblocking Supervisory Control Problem (RNSCP) of discrete event systems. In the robust control problem considered here, the plant model is assumed to belong to a given finite set of DES models.
The introduced supervisor computes the control action in online fashion and it is named Robust Limited Lookahead (RLL) supervisor. In comparison with offline supervisory control, RLL supervisor can reduce the complexity associated with the computation of control law as it looks at the behavior of system at the current state and of a limited depth in future.
Since a conservative policy is adopted here, the behavior of the system under supervision of the RLL supervisor is generally more restrictive than the optimal offline supervisor. A sufficient condition is presented under which a limited lookahead window can guarantee the optimality (maximal permissiveness) of the RLL supervisor.
In some problems, the required window length for maximally permissive RLL supervisor may become unbounded. To overcome this limitation RNSCP with State information (RNSCP-S) is studied and solved resulting in a state-based RLL (RLL-S) supervisor.
The results of this thesis can be regarded as an extension of previous work in the literature on limited lookahead policies for (non-robust) supervisory control to the case of
nonblocking robust supervisory control.
The robust limited lookahead design procedures are implemented in MATLAB environment and applied to two examples involving spacecraft propulsion systems
Digital Product Architecture and Customer Agility: Evidence from New Digital Ventures
New digital ventures are transforming the world around us. Born-digital companies (such as Uber) that were initially established to serve a specific market can quickly detect new opportunities in other markets and respond to these opportunities by reassembling their resources with speed and ease. Limited research has investigated how product architecture enables or hinders the ability of the firm to sense customer-related opportunities and respond to them effectively. By examining two new digital ventures, this study sheds light on new digital ventures’ customer agility. Specifically, we address how the characteristics of new digital ventures’ product architectures facilitate or hinder the development of the customer-sensing and customer-responding capability dimensions of customer agility. We present theoretical and managerial implications regarding how to leverage digital technologies to foster customer agility
Digital Product Architecture and Customer Agility: Evidence from New Digital Ventures
New digital ventures are transforming the world around us. Born-digital companies (such as Uber) that were initially established to serve a specific market can quickly detect new opportunities in other markets and respond to these opportunities by reassembling their resources with speed and ease. Limited research has investigated how product architecture enables or hinders the ability of the firm to sense customer-related opportunities and respond to them effectively. By examining two new digital ventures, this study sheds light on new digital ventures’ customer agility. Specifically, we address how the characteristics of new digital ventures’ product architectures facilitate or hinder the development of the customer-sensing and customer-responding capability dimensions of customer agility. We present theoretical and managerial implications regarding how to leverage digital technologies to foster customer agility
AAHES: A hybrid expert system realization of Adaptive Autonomy for smart grid
Abstract--Smart grid expectations objectify the need for
optimizing power distribution systems greater than ever.
Distribution Automation (DA) is an integral part of the SG
solution; however, disregarding human factors in the DA systems
can make it more problematic than beneficial. As a consequence,
Human-Automation Interaction (HAI) theories can be employed
to optimize the DA systems in a human-centered manner. Earlier
we introduced a novel framework for the realization of Adaptive
Autonomy (AA) concept in the power distribution network using
expert systems. This research presents a hybrid expert system for
the realization of AA, using both Artificial Neural Networks
(ANN) and Logistic Regression (LR) models, referred to as
AAHES, respectively. AAHES uses neural networks and logistic
regression as an expert system inference engine. This system
fuses LR and ANN models' outputs which will results in a
progress, comparing to both individual models. The practical list
of environmental conditions and superior experts' judgments are
used as the expert systems database. Since training samples will
affect the expert systems performance, the AAHES is
implemented using six different training sets. Finally, the results
are interpreted in order to find the best training set. As revealed
by the results, the presented AAHES can effectively determine
the proper level of automation for changing the performance
shaping factors of the HAI systems in the smart grid
environment
Cyber security for smart grid: a human-automation interaction framework
Abstract-- Power grid cyber security is turning into a vital
concern, while we are moving from the traditional power grid
toward modern Smart Grid (SG). To achieve the smart grid
objectives, development of Information Technology (IT)
infrastructure and computer based automation is necessary. This
development makes the smart grid more prone to the cyber
attacks. This paper presents a cyber security strategy for the
smart grid based on Human Automation Interaction (HAI)
theory and especially Adaptive Autonomy (AA) concept. We
scheme an adaptive Level of Automation (LOA) for Supervisory
Control and Data Acquisition (SCADA) systems. This level of
automation will be adapted to some environmental conditions
which are presented in this paper. The paper presents a brief
background, methodology (methodology design), implementation
and discussions.
Index Terms—smart grid, human automation interaction,
adaptive autonomy, cyber security, performance shaping facto
Technology Affordances in Digital Innovation Research: Quo Vadis?
Technology affordance theory has been repeatedly mentioned as a viable lens to study implications of digital technologies for innovation processes and practices. In this research article, we highlight one of the challenges of applying technology affordance theory in its current form to digital innovation research. We address the relationships between individuals and organization within innovation ecosystems. Based on insights generated from the extant literature on technology affordances as well as on digital innovation, we seek to explore the challenges of studying digital innovation through the lens of technology affordance theory. Our research integrates and expands existing theoretical perspectives on affordances to better address the needs of research on complex, emergent socio-technical phenomena such as digital innovation
An intelligent expert system for realization of adaptive autonomy using logistic regression
1
Abstract— We have introduced a novel framework for2
realization of Adaptive Autonomy (AA) in human-automation
interaction (HAI) systems, as well as several expert system
realizations of that. This study presents an expert system for
realization of AA, using logistic regression (LR), referred to as
Adaptive Autonomy Logistic Regression Expert System
(AALRES). The proposed system prescribes proper Levels of
Automation (LOAs) for various environmental conditions, here
modeled as Performance Shaping Factors (PSFs), based on the
extracted rules from the experts’ judgments. LR is used as the
expert system's inference engine. The practical list of PSFs and
the judgments of GTEDC’s (the Greater Tehran Electric
Distribution Company) experts are used as expert system
database. The results of implementing AALRES to GTEDC’s
network are evaluated against the exact predictions of the
presented expert system. Evaluations show that AALRES can
predict the proper LOA for GTEDC’s Utility Management
Automation (UMA) system, which change according to changes
in PSFs; thus providing an adaptive LOA scheme for UMA