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The structure of engineered infrastructure systems can be represented by a layered architecture. The relationship between physical components of many types of these systems has been well studied and modelled. The engineered design of these systems can account for some of their characteristics such as robustness, flexibility, reliability. We believe that the resilience, or adaptive capacity, of these systems cannot be described merely by studying the engineered components of such systems. This requires studying what we refer to as the protocol layers. The protocol layer is where humans interact with the engineered elements of the system through the collection and processing of information with the aim of producing a control activity on the system. In the first part of this study we look at several formulations of a generic layered transportation system, to discuss the importance of protocols in adaptive capability. In the second part, we take a brief historical look at an important American intermodal inland waterway transportation system, The Tennessee Valley Authority. From this system we extract some basic protocol layers and discuss how the success or failure of this system has resulted from these protocol layers.
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Online Control for Adaptive Tapering of Medications
We investigate adaptive protocols for the elimination or reduction of the use of medications or addictive substances. We formalize this problem as online optimization, minimizing the cumulative dose subject to constraints on individual well-being. We adapt a model of addiction from the psychology literature and show how it can be described by a class of linear time-invariant systems. For such systems, the optimal policy amounts to taking the smallest dose that maintains well-being. We derive a simple protocol based on integral control that requires no system identification, only needing approximate knowledge of the instantaneous dose response. This protocol is robust to model misspecification and is able to maintain an individual's well-being during the tapering process. Numerical experiments demonstrate that the adaptive protocol outperforms non-adaptive methods in terms of both maintenance of well-being and rate of dose reduction.
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- Award ID(s):
- 2326498
- PAR ID:
- 10517681
- Publisher / Repository:
- IEEE
- Date Published:
- ISBN:
- 979-8-3503-0124-3
- Page Range / eLocation ID:
- 4067 to 4074
- Format(s):
- Medium: X
- Location:
- Singapore, Singapore
- Sponsoring Org:
- National Science Foundation
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