A Single-Node Classifier Implementation on Chua Oscillator within a Physical Reservoir Computing Framework

2021 ◽  
Vol 31 (11) ◽  
pp. 2150161
Author(s):  
Uladzislau Sychou
Keyword(s):  
Computer Simulation ◽  
Control Parameter ◽  
Chaotic Oscillator ◽  
Reservoir Computing ◽  
Single Node ◽  
Short Pulses ◽  
Chaotic Mode ◽  
Computing Framework ◽  
Chua Oscillator

The study lies in the field of physical reservoir computing and aims to develop a classifier using Fisher Iris dataset for benchmark tasks. Single Chua chaotic oscillator acts as a physical reservoir. The study was performed using computer simulation. The features of Iris flowers are represented as the consequence of short pulses at a constant level of a control parameter, which is fed to the oscillator, changing its dynamics. During the classification of flowers, the oscillator works without being reset, so each pulse on the input changes the phase trajectory and makes it unique for each Iris flower. Finally, the estimation of the symmetry of an attractor makes it possible to connect each species of Iris with the properties of the attractor. The resulting architecture of the classifier includes a single-node externally-driven Chua oscillator with time-delayed input. The classifier shows two mistakes in classifying the dataset with 75 samples working in chaotic mode.

Decision support or autonomous artificial intelligence? The case of wrong blood in tube errors

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Christopher-John L. Farrell
Keyword(s):  
Neural Network ◽  
Artificial Intelligence ◽  
Artificial Neural Network ◽  
Computer Simulation ◽  
Clinical Chemistry ◽  
Human Interaction ◽  
Final Decision ◽  
P Values ◽  
Laboratory Staff

Abstract Objectives Artificial intelligence (AI) models are increasingly being developed for clinical chemistry applications, however, it is not understood whether human interaction with the models, which may occur once they are implemented, improves or worsens their performance. This study examined the effect of human supervision on an artificial neural network trained to identify wrong blood in tube (WBIT) errors. Methods De-identified patient data for current and previous (within seven days) electrolytes, urea and creatinine (EUC) results were used in the computer simulation of WBIT errors at a rate of 50%. Laboratory staff volunteers reviewed the AI model’s predictions, and the EUC results on which they were based, before making a final decision regarding the presence or absence of a WBIT error. The performance of this approach was compared to the performance of the AI model operating without human supervision. Results Laboratory staff supervised the classification of 510 sets of EUC results. This workflow identified WBIT errors with an accuracy of 81.2%, sensitivity of 73.7% and specificity of 88.6%. However, the AI model classifying these samples autonomously was superior on all metrics (p-values<0.05), including accuracy (92.5%), sensitivity (90.6%) and specificity (94.5%). Conclusions Human interaction with AI models can significantly alter their performance. For computationally complex tasks such as WBIT error identification, best performance may be achieved by autonomously functioning AI models.

Improved Positioning of Pneumatic Cylinder by Using Flexible Coupling between the Piston and Rod

1992 ◽  
Vol 206 (6) ◽  
pp. 431-435 ◽  
Author(s):  
G V Krejnin ◽  
I L Krivz ◽  
L A Smelov
Keyword(s):  
Mathematical Model ◽  
Computer Simulation ◽  
Parameter Optimization ◽  
Degrees Of Freedom ◽  
Control Parameter ◽  
Pneumatic Cylinder ◽  
Output Link ◽  
Positioning Accuracy ◽  
Flexible Coupling ◽  
And Control

Positioning accuracy of a pneumatic piston drive with flexible coupling between the piston and rod is considered. Improved positioning was expected due to the fact that the rod friction is usually considerably less than the piston friction. When the piston stops under the action of its friction force the rod continues the motion, providing the precision positioning of the output link. A mathematical model of a positioning pneumatic piston drive with two degrees of freedom was generated. Computer simulation of the performance of short and long strokes showed the feasibility of the improved positioning which provided design and control parameter optimization.

scholarly journals Optimized Computation of Tight Focusing of Short Pulses Using Mapping to Periodic Space

2021 ◽  
Vol 11 (3) ◽  
pp. 956
Author(s):  
Elena Panova ◽  
Valentin Volokitin ◽  
Evgeny Efimenko ◽  
Julien Ferri ◽  
Thomas Blackburn ◽  
...  
Keyword(s):  
Near Field ◽  
Finite Difference Methods ◽  
Laser Pulses ◽  
Numerical Dispersion ◽  
Far Field ◽  
Single Node ◽  
Short Pulses ◽  
Tight Focusing ◽  
The Stability ◽  
Periodic Space

When a pulsed, few-cycle electromagnetic wave is focused by optics with f-number smaller than two, the frequency components it contains are focused to different regions of space, building up a complex electromagnetic field structure. Accurate numerical computation of this structure is essential for many applications such as the analysis, diagnostics, and control of high-intensity laser-matter interactions. However, straightforward use of finite-difference methods can impose unacceptably high demands on computational resources, owing to the necessity of resolving far-field and near-field zones at sufficiently high resolution to overcome numerical dispersion effects. Here, we present a procedure for fast computation of tight focusing by mapping a spherically curved far-field region to periodic space, where the field can be advanced by a dispersion-free spectral solver. In many cases of interest, the mapping reduces both run time and memory requirements by a factor of order 10, making it possible to carry out simulations on a desktop machine or a single node of a supercomputer. We provide an open-source C++ implementation with Python bindings and demonstrate its use for a desktop machine, where the routine provides the opportunity to use the resolution sufficient for handling the pulses with spectra spanning over several octaves. The described approach can facilitate the stability analysis of theoretical proposals, the studies based on statistical inferences, as well as the overall development and analysis of experiments with tightly-focused short laser pulses.

scholarly journals Ceiling and Wall Illumination, Utilance, and Power in Interior Lighting

Energies ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 4744 ◽  
Author(s):  
Piotr Pracki ◽  
Michał Dziedzicki ◽  
Paulina Komorzycka
Keyword(s):  
Energy Efficiency ◽  
Computer Simulation ◽  
Lighting System ◽  
Room Size ◽  
Interior Lighting ◽  
Analysis Of Results ◽  
The Common ◽  
The Impact ◽  
Illuminance Uniformity

The common use of electric lighting in interiors has led to the need to search for user- and environmentally-friendly solutions. In this research, the impact of the luminaires and room parameters on the selected parameters of general lighting in interiors was assessed. To achieve the objective of this work, a computer simulation and statistical analysis of results were conducted. The illuminance uniformity on work plane, ceiling and wall relative illuminances, utilance, and normalized power density of lighting installations for 432 situations were analyzed in detail. The scenarios were varied in terms of room size, reflectance, lighting class, luminaire downward luminous intensity distribution, and layout. The lighting class was a factor having the highest impact on ceiling and wall illumination, utilance, and power. It was also shown that the impact of lighting class on ceiling illumination, utilance and power, was different in interiors of various sizes. The impact of reflectances and luminaire layouts on the analyzed parameters was significantly lower. The results also demonstrated that the use of different lighting classes gave the possibility of reducing the power of general lighting in interiors at a level of 30% on average. Based on the results, a classification of energy efficiency in general lighting in interiors was also proposed. Understanding the correlations between the lighting system used and the effects achieved is helpful in obtaining comfortable and efficient lighting solutions in interiors.

Classification of the Extent of Wall Thinning in Pipes Based on Simulations in the Time and Frequency Domain

2016 ◽  
Author(s):  
Wissam M. Alobaidi ◽  
Eric Sandgren
Keyword(s):  
Pattern Recognition ◽  
Computer Simulation ◽  
Nondestructive Testing ◽  
Pipe Wall ◽  
Circular Waveguide ◽  
Testing System ◽  
Cross Sectional ◽  
Wall Thinning ◽  
Degree Of Similarity

Numerical simulations created with Computer Simulation Technology (CST) modeling are used to classify and evaluate the microwave signal (waveform) in order to determine whether various parameters of pipe wall thinning (PWT) can be identified. Microwaves are used to carry out the measurement of PWT in 9 CST simulations using three cross-sectional profiles, three lengths of PWT, and three depths of PWT, to determine whether there are differences in waveforms that can be used to distinguish the parameters of unknown discontinuities (PWT). The modeled system uses the pipe as a circular waveguide (bandwidth 0.486GHz) with sweeping frequencies from 1.914GHz to 2.4GHz. Waveforms are found to be distinguishable based on the three parameters modeled in the study. This research establishes the possibility of creating a nondestructive testing system with which PWT discontinuities might be characterized using microwaves in the S11 and S21 scattering parametrics. The waveforms generated for known series of PWT cases, once cataloged, can be used in the future to identify discontinuities in test pipes, and to determine their degree of similarity to the standardized waveforms via pattern recognition algorithms.

Sign in / Sign up

Export Citation Format

Share Document