Generalized Hopfield networks for associative memories with multi-valued stable states

<div>In the two-balloon experiment, two rubber balloons are connected and allowed to exchange gas. Owing to the non-monotonic relationship between the radius of the balloon and the pressure of gas inside of it, the two-balloon system presents multi- and in-stabilities.</div><div><br></div><div>Herein, we consider a two-adsorbent system, where two different adsorbents are allowed to exchange gas. We show that, for rigid adsorbents, the thermodynamic equilibrium state is unique.</div><div><br></div><div>Then, we consider an adsorbent-balloon system, where an adsorbent exchanges gas with a rubber balloon. This system can exhibit multiple states at thermodynamic equilibrium-- two (meta)stable and one unstable. The size of the balloon, pressure of gas in the balloon, and partitioning of gas between the adsorbent and the balloon differ among the equilibrium states. Temperature changes and the addition/removal of gas into/from the adsorbent-balloon system can induce catastrophe bifurcations and show hysteresis. Furthermore, the adsorbent-balloon system exhibits a critical temperature where, when approached from below, the discrepancy of balloon size between the two (meta)stable states decreases and, beyond, bistability is impossible.</div><div><br></div><div>Practically, our findings preclude multiple partitions of adsorbed gas in rigid mixed-linker metal-organic frameworks and may inspire new soft actuator and sensor designs.</div>

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Faculty Opinions recommendation of Alternative stable states explain unpredictable biological control of Salvinia molesta in Kakadu.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.8454956.8919054 ◽

2011 ◽

Author(s):

Katia Koelle

Keyword(s):

Biological Control ◽

Alternative Stable States ◽

Salvinia Molesta ◽

Stable States

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Applying Associative Memories To Fault Location Identification

10.21528/cbrn1994-045 ◽

2016 ◽

Author(s):

A. P. Alves da Silva ◽

A. H. F. Insfran ◽

P. M. da Silveira ◽

G. Lambert-Torres

Keyword(s):

Fault Location ◽

Associative Memories ◽

Location Identification

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A Study of Taxi Service Mode Choice Based on Evolutionary Game Theory

Journal of Advanced Transportation ◽

10.1155/2019/8607942 ◽

2019 ◽

Vol 2019 ◽

pp. 1-17

Author(s):

Zhu Bai ◽

Mingxia Huang ◽

Shuai Bian ◽

Huandong Wu

Keyword(s):

Game Theory ◽

Evolutionary Game Theory ◽

Mode Choice ◽

Evolutionary Game ◽

Payoff Matrix ◽

Game Model ◽

Stable States ◽

Taxi Service ◽

Service Mode ◽

The Impact

The emergence of online car-hailing service provides an innovative approach to vehicle booking but has negatively influenced the taxi industry in China. This paper modeled taxi service mode choice based on evolutionary game theory (EGT). The modes included the dispatching and online car-hailing modes. We constructed an EGT framework, including determining the strategies and the payoff matrix. We introduced different behaviors, including taxi company management, driver operation, and passenger choice. This allowed us to model the impact of these behaviors on the evolving process of service mode choice. The results show that adjustments in taxi company, driver, and passenger behaviors impact the evolutionary path and convergence speed of our evolutionary game model. However, it also reveals that, regardless of adjustments, the stable states in the game model remain unchanged. The conclusion provides a basis for studying taxi system operation and management.

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Hierarchical mechanical metamaterials built with scalable tristable elements for ternary logic operation and amplitude modulation

Science Advances ◽

10.1126/sciadv.abf1966 ◽

2021 ◽

Vol 7 (9) ◽

pp. eabf1966

Author(s):

Hang Zhang ◽

Jun Wu ◽

Daining Fang ◽

Yihui Zhang

Keyword(s):

Structural Diversity ◽

Cell Number ◽

Structural Elements ◽

Ternary Logic ◽

Stable States ◽

One Dimensional ◽

Logic Operation ◽

Artificial Materials ◽

Mechanical Metamaterials ◽

Unit Cells

Multistable mechanical metamaterials are artificial materials whose microarchitectures offer more than two different stable configurations. Existing multistable mechanical metamaterials mainly rely on origami/kirigami-inspired designs, snap-through instability, and microstructured soft mechanisms, with mostly bistable fundamental unit cells. Scalable, tristable structural elements that can be built up to form mechanical metamaterials with an extremely large number of programmable stable configurations remains illusive. Here, we harness the elastic tensile/compressive asymmetry of kirigami microstructures to design a class of scalable X-shaped tristable structures. Using these structure as building block elements, hierarchical mechanical metamaterials with one-dimensional (1D) cylindrical geometries, 2D square lattices, and 3D cubic/octahedral lattices are designed and demonstrated, with capabilities of torsional multistability or independent controlled multidirectional multistability. The number of stable states increases exponentially with the cell number of mechanical metamaterials. The versatile multistability and structural diversity allow demonstrative applications in mechanical ternary logic operators and amplitude modulators with unusual functionalities.

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Kinetics studies on free radical scavenging property of ceria in polysulfone–ceria radiation resistant mixed-matrix membrane

International Journal of Chemical Reactor Engineering ◽

10.1515/ijcre-2020-0123 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Amita Bedar ◽

Beena G. Singh ◽

Pradip K. Tewari ◽

Ramesh C. Bindal ◽

Soumitra Kar

Keyword(s):

Radical Scavenging ◽

Radiation Environment ◽

Mixed Matrix Membranes ◽

Mixed Matrix Membrane ◽

Ceria Nanoparticles ◽

Ros Scavenging ◽

Mixed Matrix ◽

Stable States ◽

Host Matrix ◽

Γ Radiation

Abstract Cerium oxide (ceria) contains two stable states of cerium ions (Ce3+ and Ce4+). The presence of these two states and the ability to swap from one state to another (Ce3+ ↔ Ce4+) by scavenging the highly reactive oxygen species (ROS) generated from radiolysis of water, ensure the enhanced stability of polysulfone (Psf) membranes in the γ-radiation environment. In this study, the ROS scavenging ability of ceria was studied. Ceria nanoparticles were found to scavenge ROS like hydroxyl radicals and hydrogen peroxide (H2O2). The H2O2 scavenging is due to the peroxidase-like catalytic activity of ceria nanoparticles. The ROS scavenging is responsible for offering protection to the Psf host matrix and in turn the stability to the Psf-ceria mixed-matrix membranes (MMMs) in γ-radiation environment. Thus, presence of ceria nanoparticles provides an opportunity for utilizing Psf-ceria MMMs in ionizing radiation environment with increased life span, without compromise in the performance.

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Single Neuronal Dynamical System in Self-Feedbacked Hopfield Networks and Its Application in Image Encryption

Entropy ◽

10.3390/e23040456 ◽

2021 ◽

Vol 23 (4) ◽

pp. 456

Author(s):

Xitong Xu ◽

Shengbo Chen

Keyword(s):

Dynamical System ◽

Image Encryption ◽

Chaotic Dynamic ◽

Security Analysis ◽

High Sensitivity ◽

Hopfield Network ◽

Complex Structures ◽

Hopfield Networks ◽

Discrete Form ◽

Chaotic Parameter

Image encryption is a confidential strategy to keep the information in digital images from being leaked. Due to excellent chaotic dynamic behavior, self-feedbacked Hopfield networks have been used to design image ciphers. However, Self-feedbacked Hopfield networks have complex structures, large computational amount and fixed parameters; these properties limit the application of them. In this paper, a single neuronal dynamical system in self-feedbacked Hopfield network is unveiled. The discrete form of single neuronal dynamical system is derived from a self-feedbacked Hopfield network. Chaotic performance evaluation indicates that the system has good complexity, high sensitivity, and a large chaotic parameter range. The system is also incorporated into a framework to improve its chaotic performance. The result shows the system is well adapted to this type of framework, which means that there is a lot of room for improvement in the system. To investigate its applications in image encryption, an image encryption scheme is then designed. Simulation results and security analysis indicate that the proposed scheme is highly resistant to various attacks and competitive with some exiting schemes.

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