Nonlinear Behavior of Dendritic Polymer Networks for Reservoir Computing

Pulp and paper processes frequently present nonlinear behavior, which means that process dynam-ics change with the operating points. These nonlinearities can challenge process control. PID controllers are the most popular controllers because they are simple and robust. However, a fixed set of PID tuning parameters is gen-erally not sufficient to optimize control of the process. Problems related to nonlinearities such as sluggish or oscilla-tory response can arise in different operating regions. Gain scheduling is a potential solution. In processes with mul-tiple control objectives, the control strategy must further evaluate loop interactions to decide on the pairing of manipulated and controlled variables that minimize the effect of such interactions and hence, optimize controller’s performance and stability. Using the CADSIM Plus™ commercial simulation software, we developed a Jacobian sim-ulation module that enables automatic bumps on the manipulated variables to calculate process gains at different operating points. These gains can be used in controller tuning. The module also enables the control system designer to evaluate loop interactions in a multivariable control system by calculating the Relative Gain Array (RGA) matrix, of which the Jacobian is an essential part.

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REDUCED MODEL OF PLASMA DISCHARGE CONTROL IN TOKAMAK WITH IRON CORE

Computational nanotechnology ◽

10.33693/2313-223x-2020-7-3-11-22 ◽

2020 ◽

Vol 7 (3) ◽

pp. 11-22

Author(s):

VALERY ANDREEV ◽

◽

ALEXANDER POPOV

Keyword(s):

Optimal Control ◽

Inverse Problem ◽

Optimal Control Problem ◽

Control Problem ◽

Nonlinear Behavior ◽

Plasma Discharge ◽

Reduced Model ◽

Iron Core ◽

Power Sources ◽

Real Power

A reduced model has been developed to describe the time evolution of a discharge in an iron core tokamak, taking into account the nonlinear behavior of the ferromagnetic during the discharge. The calculation of the discharge scenario and program regime in the tokamak is formulated as an inverse problem - the optimal control problem. The methods for solving the problem are compared and the analysis of the correctness and stability of the control problem is carried out. A model of “quasi-optimal” control is proposed, which allows one to take into account real power sources. The discharge scenarios are calculated for the T-15 tokamak with an iron core.

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Crosslinker Chemistry Determines the Uptake Potential of Perfluorinated Alkyl Substances by β-Cyclodextrin Polymers

10.26434/chemrxiv.7492631.v2 ◽

2018 ◽

Author(s):

Leilei Xiao ◽

Casey Ching ◽

Yuhan Ling ◽

Mohammadreza Nasiri ◽

Max Justin Klemes ◽

...

Keyword(s):

Binding Affinity ◽

Polymer Networks ◽

Cyclodextrin Polymer ◽

Perfluorinated Alkyl Substances ◽

Cyclodextrin Polymers

This work describes several crosslinked β-cyclodextrin polymer networks and correlates the crosslinker chemistry with binding affinity for per- and polyfluorinated alkyl substances (PFASs), including PFOA and PFOS.

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Design and Synthesis of Two-Dimensional Covalent Organic Frameworks with Four-Arm Cores: Prediction of Remarkable Ambipolar Charge-Transport Properties

10.26434/chemrxiv.7766786.v2 ◽

2019 ◽

Author(s):

Simil Thomas ◽

Hong Li ◽

Raghunath R. Dasari ◽

Austin Evans ◽

William Dichtel ◽

...

Keyword(s):

Charge Transport ◽

Organic Semiconductors ◽

Density Functional ◽

Polymer Networks ◽

Two Dimensional ◽

Covalent Organic Frameworks ◽

X Ray Diffraction ◽

Zinc Porphyrin ◽

Design And Synthesis ◽

Predicted Values

We have considered three two-dimensional (2D) π-conjugated polymer networks (i.e., covalent organic frameworks, COFs) materials based on pyrene, porphyrin, and zinc-porphyrin cores connected via diacetylenic linkers. Their electronic structures, investigated at the density functional theory global-hybrid level, are indicative of valence and conduction bands that have large widths, ranging between 1 and 2 eV. Using a molecular approach to derive the electronic couplings between adjacent core units and the electron-vibration couplings, the three π-conjugated 2D COFs are predicted to have ambipolar charge-transport characteristics with electron and hole mobilities in the range of 65-95 cm2V-1s-1. Such predicted values rank these 2D COFs among the highest-mobility organic semiconductors. In addition, we have synthesized the zinc-porphyrin based 2D COF and carried out structural characterization via powder X-ray diffraction and surface area analysis, which demonstrates the feasability of these electroactive networks.

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