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2021 ◽  
Author(s):  
Bruce Ecker

The annulment of a human emotional memory through reconsolidation behavioral updating has been documented in over twenty laboratory studies since the first such report in 2010. However, fourteen studies have reported non-replication, the cause(s) of which remain unclear. This review examines all successful and unsuccessful studies in detail, in an attempt to identify (a) the specific probable causes of non-replication and (b) how clinical translation might optimally be designed. For analyzing non-replications, a set of criteria is defined for principled identification of specific moments of prediction error (PE) in experimental procedures, including latent cause transitions, based on a preponderance of empirical evidence. A previously overlooked element of experimental procedure is in that way identified as being potentially decisive, and a unified, testable explanation is proposed for behavioral updating successes and failures in terms of the presence or absence of a PE experience. That in turn allows successful studies to be compared for the internal experiences induced in subjects, rather than compared for their external procedures, revealing an invariant set of three experiences shared by all successful updating studies despite their diverse procedures. Clinical translation, defined as replication of those experiences, not any particular procedure, is illustrated by an actual case, one of many published cases that have documented prompt transformational change produced by that specific methodology, suggesting memory reconsolidation as the mechanism of change. Lastly, the core empirical findings of successful reconsolidation updating studies are compared with previously proposed frameworks of memory reconsolidation in psychotherapy, exposing significant departures from scientific fidelity.


2021 ◽  
Author(s):  
Hyung Tae Choi ◽  
Jung Hoon Kim

Abstract This paper is concerend with tackling the L 1 performance analysis problem of continuous and piecewise continuous nonlinear systems with non-unique solutions by using the involved arguments of set-invariance principles. More precisely, this paper derives a sufficient condition for the L 1 performance of continuous nonlinear systems in terms of the invariant set. However, because this sufficient condition intrinsically involves analytical representations of solutions of the differential equations corresponding to the nonlinear systems, this paper also establishes another sufficient condition for the L 1 performance by introducing the so-called extended invariance domain, in which it is not required to directly solving the nonlinear differential equations. These arguments associated with the L 1 performance analysis is further extended to the case of piecewise continuous nonlinear systems, and we obtain parallel results based on the set-invariance principles used for the continuous nonolinear systems. Finally, numerical examples are provided to demonstrate the effectiveness as well as the applicability of the overall results derived in this paper.


Mathematics ◽  
2021 ◽  
Vol 9 (14) ◽  
pp. 1651
Author(s):  
Andrei Alexandru ◽  
Gabriel Ciobanu

We present a survey of some results published recently by the authors regarding the fuzzy aspects of finitely supported structures. Considering the notion of finite support, we introduce a new degree of membership association between a crisp set and a finitely supported function modelling a degree of membership for each element in the crisp set. We define and study the notions of invariant set, invariant complete lattices, invariant monoids and invariant strong inductive sets. The finitely supported (fuzzy) subgroups of an invariant group, as well as the L-fuzzy sets on an invariant set (with L being an invariant complete lattice) form invariant complete lattices. We present some fixed point results (particularly some extensions of the classical Tarski theorem, Bourbaki–Witt theorem or Tarski–Kantorovitch theorem) for finitely supported self-functions defined on invariant complete lattices and on invariant strong inductive sets; these results also provide new finiteness properties of infinite fuzzy sets. We show that apparently, large sets do not contain uniformly supported, infinite subsets, and so they are invariant strong inductive sets satisfying finiteness and fixed-point properties.


2021 ◽  
pp. 107754632110280
Author(s):  
Xindong Si ◽  
Hongli Yang

Constrained regulation problem (CRP) for continuous-time stochastic systems is investigated in this article. New existence conditions of linear feedback control law for continuous-time stochastic systems under constraints are proposed. The computation method for solving constrained regulation problem of stochastic systems considered in this article is also presented. Continuous-time stochastic linear systems and stochastic nonlinear systems are focused on, respectively. First, the condition of polyhedral invariance for stochastic systems is established by using the theory of positive invariant set and the principle of comparison. Second, the asymptotic stability conditions in the sense of expectation for two types of stochastic systems are established. Finally, finding the linear feedback controller model and corresponding algorithm of constrained regulation problem for two types of stochastic systems are also proposed by using the obtained condition. The presented model of the stochastic constrained regulation problem in this article is formulated as a linear programming problem, which can be easily implemented from a computational point of view. Our approach establishes a connection between the stochastic constrained regulation problem and positively invariant set theory, as well as provides the possibility of using optimization methodology to find the solution of stochastic constrained regulation problem, which differs from other methods. Numerical examples illustrate the proposed method.


2021 ◽  
Vol 8 ◽  
Author(s):  
Bryan Convens ◽  
Kelly Merckaert ◽  
Bram Vanderborght ◽  
Marco M. Nicotra

This article provides a theory for provably safe and computationally efficient distributed constrained control, and describes an application to a swarm of nano-quadrotors with limited on-board hardware and subject to multiple state and input constraints. We provide a formal extension of the explicit reference governor framework to address the case of distributed systems. The efficacy, robustness, and scalability of the proposed theory is demonstrated by an extensive experimental validation campaign and a comparative simulation study on single and multiple nano-quadrotors. The control strategy is implemented in real-time on-board palm-sized unmanned erial vehicles, and achieves safe swarm coordination without relying on any offline trajectory computations.


2021 ◽  
Author(s):  
Yu-Ping Tian ◽  
Wenbo Zhu

Abstract Target detection based on wireless sensor networks can be considered as a distributed binary hypothesis testing problem. In this paper, the evolution of detection error probability with the increase of network scale is studied for the balanced binary relay tree network with channel noise. Firstly, the iterative expressions of false-alarm probability and missed-detection probability depending on the number of tree network layers are given. Then, the iterative process of two types of error probabilities in the network space is described as a discrete nonlinear switched dynamic system, and the dynamic properties of two types of error probabilities are analyzed in a plane rectangular coordinate system. A globally attractive invariant set of the state of the dynamic system, which is not related to the channel noise, is derived. The switching mode of the system and the total error probability in the invariant set are further analyzed, and a necessary and sufficient convergence condition of the total error probability is provided. Based on this condition the following detection properties of the network are revealed: (1) as long as the channel bit error probability is not zero, the total error probability does not tend to zero with the increasing network size; (2) when the channel bit error probability is greater than 2-/3/ 2 the total error probability will continue to increase with the increase of network size.


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