Computational and experimental studies of microvascular void features for passive-adaptation of structural panel dynamic properties

2018 ◽  
Vol 412 ◽  
pp. 17-27 ◽  
Author(s):  
Nicholas C. Sears ◽  
Ryan L. Harne
Keyword(s):  
Dynamic Properties ◽  
Experimental Studies ◽  
Structural Panel

scholarly journals Adaptive Control Structure with Neural Data Processing Applied for Electrical Drive with Elastic Shaft

Energies ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3389
Author(s):  
Marcin Kamiński ◽  
Krzysztof Szabat
Keyword(s):  
Neural Network ◽  
Adaptive Control ◽  
Dynamic Properties ◽  
Experimental Studies ◽  
Drive System ◽  
Particle Swarm Optimizer ◽  
The Neural Network ◽  
Control Concept ◽  
Constant Coefficients ◽  
Selection Of

This paper presents issues related to the adaptive control of the drive system with an elastic clutch connecting the main motor and the load machine. Firstly, the problems and the main algorithms often implemented for the mentioned object are analyzed. Then, the control concept based on the RNN (recurrent neural network) for the drive system with the flexible coupling is thoroughly described. For this purpose, an adaptive model inspired by the Elman model is selected, which is related to internal feedback in the neural network. The indicated feature improves the processing of dynamic signals. During the design process, for the selection of constant coefficients of the controller, the PSO (particle swarm optimizer) is applied. Moreover, in order to obtain better dynamic properties and improve work in real conditions, one model based on the ADALINE (adaptive linear neuron) is introduced into the structure. Details of the algorithm used for the weights’ adaptation are presented (including stability analysis) to perform the shaft torque signal filtering. The effectiveness of the proposed approach is examined through simulation and experimental studies.

Studies of Magnetically Active Silicone Elastomers on a Vibrostend

2021 ◽  
Vol 1037 ◽  
pp. 141-147
Author(s):  
Andrey Minaev ◽  
Juri Korovkin ◽  
Hammat Valiev ◽  
G.V. Stepanov ◽  
Dmitry Yu. Borin
Keyword(s):  
Magnetic Field ◽  
Field Effect ◽  
Dynamic Properties ◽  
Experimental Studies ◽  
Magnetic Field Effect ◽  
Magnetorheological Elastomer ◽  
Silicone Elastomers ◽  
Damping Coefficients ◽  
Deformation Properties ◽  
The Magnetic Field

Experimental studies magnetorheological elastomer specimens dynamic properties under the magnetic fields action on the vibrostend are carried out. Amplitude-frequency characteristics have been obtained. The magnetic field effect on the silicone magnetoreactive elastomers deformation properties and damping coefficients experimentally is established.

Enhanced A Horizon Framework and Field Form for detailed field scale monitoring of dynamic soil properties

2014 ◽  
Vol 94 (2) ◽  
pp. 189-208 ◽  
Author(s):  
Catherine A. Fox ◽  
Charles Tarnocai ◽  
Gabriele Broll ◽  
Monika Joschko ◽  
David Kroetsch ◽  
...  
Keyword(s):  
Soil Properties ◽  
Best Management Practices ◽  
Management Practices ◽  
Dynamic Properties ◽  
Experimental Studies ◽  
Density Level ◽  
Field Scale ◽  
Dynamic Soil Properties ◽  
Field Form ◽  
Fingerprint Code

Fox, C. A., Tarnocai, C., Broll, G., Joschko, M., Kroetsch, D. and Kenney, E. 2014. Enhanced A Horizon Framework and Field Form for detailed field scale monitoring of dynamic soil properties. Can. J. Soil Sci. 94: 189–208. Taxonomic protocols for A horizon description are limited when detailed monitoring of soil change in dynamic soil properties is required for determining the effectiveness of best management practices, remediation efforts, and assessing subtle impacts on soil properties from environmental and anthropogenic stressors. The A Horizon Framework was designed by consolidating protocols from national and international description systems and expert opinion to optimize descriptive capability through use of additional enhanced lowercase designators. The Framework defines new protocols and syntax resulting in a unique soil fingerprint code. Five levels of enhanced lowercase A horizon designators are defined: Level 1, Soil processes and environmental context; Level 2, Soil structure-bulk density; Level 3, Organic carbon; Level 4, pH and electrical conductivity; and, Level 5, Soil and landscape context (i.e., soil texture, surface conditions, current land use, slope character). An electronic Field Form based on the new Framework syntax automatically records the soil fingerprint code in an enhanced (all Levels included) and a minimum detail mode focused on the key dynamic properties. The soil fingerprint codes become a powerful tool by which to identify trends of soil change and small alterations in the dynamic soil properties. Examples of soil fingerprint codes from selected Canada and Germany long-term experimental studies are presented.

DYNAMIC COMPRESSIBILITY OF HIGH-POROSITY DAMPERS OF THERMAL AND SHOCK LOADINGS: MODELING AND EXPERIMENT

2008 ◽  
Vol 22 (09n11) ◽  
pp. 1183-1188 ◽  
Author(s):  
ANATOLY BRAGOV ◽  
ALEXANDER KONSTANTINOV ◽  
ANDREY LOMUNOV ◽  
ANATOLY SADYRIN ◽  
IVAN SERGEICHEV ◽  
...  
Keyword(s):  
Dynamic Properties ◽  
Porous Ceramic ◽  
Experimental Studies ◽  
Ceramic Materials ◽  
Heat Of Fusion ◽  
High Porosity ◽  
Dynamic Compressibility ◽  
Damping Materials ◽  
The Mathematical Model ◽  
Highly Porous

High-porosity materials, such as chamotte and mullite, possess a heat of fusion. Owing to their properties, these materials can be used with success as damping materials in containers for airplane, automobile, etc. transportation of radioactive or highly toxic materials. Experimental studies of the dynamic properties have been executed with using some original modifications of the Kolsky method. These modified experiments have allowed studying the dynamic compressibility of high-porosity chamotte at deformations up to 80% and amplitudes up to 50 MPa. The equations of the mathematical model describing shock compacting of chamotte as a highly porous, fragile, collapsing material are presented. Deformation of high-porous materials at non-stationary loadings is usually accompanied by fragile destruction of interpore partitions as observed in other porous ceramic materials. Comparison of numerical and experimental results has shown their good conformity.

scholarly journals Genetic Algorithm Approach for Gains Selection of Induction Machine Extended Speed Observer

Energies ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 4632
Author(s):  
Daniel Wachowiak
Keyword(s):  
Nonlinear Equations ◽  
Dynamic Properties ◽  
Fitness Function ◽  
Experimental Studies ◽  
Induction Machine ◽  
Loop Control ◽  
Rotation Direction ◽  
Machine Speed ◽  
Poles Placement ◽  
Selection Of

The subject of this paper is gains selection of an extended induction machine speed observer. A high number of gains makes manual gains selection difficult and due to nonlinear equations of the observer, well-known methods of gains selection for linear systems cannot be applied. A method based on genetic algorithms has been proposed instead. Such an approach requires multiple fitness function calls; therefore, using a quality index based on simulations makes gains selection a time-consuming process. To find a fitness function that evaluates, in a short time, quality indices based on poles placement have been proposed. As the observer is nonlinear, equations describing the observer dynamics have been linearized. The relationship between poles placement and real dynamic properties has been shown. A series of studies has been performed to investigate the influence of the operating point of the machine on the dynamics of the observer. It has been proven that rotor speed has a significant impact on the placement of the poles and the observer may lose stability after a rotation direction change. A method of gains modification to maintain symmetrical properties of the observer for both directions has been presented. Experimental studies of the observer during machine reverse in the open and closed-loop control system have been performed. The results show that the observer can be implemented in a sensorless drive, using the proposed gains selection method.

scholarly journals Modeling of Protein Structural Flexibility and Large-Scale Dynamics: Coarse-Grained Simulations and Elastic Network Models

2018 ◽  
Vol 19 (11) ◽  
pp. 3496 ◽  
Author(s):  
Sebastian Kmiecik ◽  
Maksim Kouza ◽  
Aleksandra Badaczewska-Dawid ◽  
Andrzej Kloczkowski ◽  
Andrzej Kolinski
Keyword(s):  
Structure Prediction ◽  
Large Scale ◽  
Dynamic Properties ◽  
Experimental Studies ◽  
Network Models ◽  
Conformational Transitions ◽  
Conformational Space ◽  
Coarse Grained ◽  
Elastic Network ◽  
Elastic Network Models

Fluctuations of protein three-dimensional structures and large-scale conformational transitions are crucial for the biological function of proteins and their complexes. Experimental studies of such phenomena remain very challenging and therefore molecular modeling can be a good alternative or a valuable supporting tool for the investigation of large molecular systems and long-time events. In this minireview, we present two alternative approaches to the coarse-grained (CG) modeling of dynamic properties of protein systems. We discuss two CG representations of polypeptide chains used for Monte Carlo dynamics simulations of protein local dynamics and conformational transitions, and highly simplified structure-based elastic network models of protein flexibility. In contrast to classical all-atom molecular dynamics, the modeling strategies discussed here allow the quite accurate modeling of much larger systems and longer-time dynamic phenomena. We briefly describe the main features of these models and outline some of their applications, including modeling of near-native structure fluctuations, sampling of large regions of the protein conformational space, or possible support for the structure prediction of large proteins and their complexes.

scholarly journals A Novel Method for Changing the Dynamics of Slender Elements Using Sponge Particles Structures

Materials ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 4874
Author(s):  
Mateusz Żurawski ◽  
Bogumił Chiliński ◽  
Robert Zalewski
Keyword(s):  
Mathematical Model ◽  
Dynamic Properties ◽  
Experimental Studies ◽  
Continuous Model ◽  
Particle Structure ◽  
System Parameters ◽  
Mass Redistribution ◽  
Novel Method ◽  
The Mathematical Model ◽  
Theoretical Considerations

The paper concerns problems related to controlling the dynamic properties of beam-like elements. The parameters of the investigated system can be changed by external factors, resulting in partial changes in the system mass redistribution. It is assumed that it is possible to control the system dynamics by shaping the object frequency structure. The paper introduces the mathematical model of the investigated cantilever beam filled with a Sponge Particle Structure. The continuous model has been simplified to a discrete multi-degree of freedom system. The influence of the system parameters on its behavior is discussed in details. The possible applications of the presented concept are proposed. The spectral vibration analyses were carried out. Theoretical considerations enabled the use of the preliminary semi-active method for controlling the vibration frequencies through a mass redistribution. Experimental studies were carried out to verify the proposed mathematical model.

Structural optimization and physical properties of TcB3 and MoB3 at high-pressure: First-principles

2016 ◽  
Vol 30 (20) ◽  
pp. 1650131 ◽  
Author(s):  
Chun Ying ◽  
Xiaowan Bai ◽  
Yungang Du ◽  
Erjun Zhao ◽  
Lin Lin ◽  
...  
Keyword(s):  
High Pressure ◽  
First Principles ◽  
Density Functional ◽  
Dynamic Properties ◽  
Experimental Studies ◽  
Formation Enthalpy ◽  
High Hardness ◽  
Stable Phase ◽  
Ambient Conditions ◽  
Strong Hybridization

The thermodynamic, mechanical and dynamic properties of TcB3 and MoB3 are systematically investigated at high-pressure by first-principles within density functional theory (DFT). The calculated formation enthalpies are negative for TcB3 with considered structures under the pressure range from 0 to 100 GPa. Triboride hP4-TcB3 (i.e., TcB3 in hP4-OsB3 type structure) has the lowest formation enthalpy of −1.44 eV under ambient condition. The largest shear modulus of 240 GPa and smallest Poisson’s ratio of 0.20 for oP16-TcB3 are comparable to those of 267 GPa and 0.15 for ReB2. The calculated elastic constants show that MB3 (M=Tc and Mo) are mechanically stable at ambient conditions, except for mP8-MoB3. The estimated high hardness of 33.4 and 33.1 GPa for oP16-TcB3 and hP4-TcB3, respectively, are reported for the first time. The calculated lattice parameters for MoB3 are in good agreement with the previously theoretical and experimental studies. Below 13 GPa, hP16-MoB3 and hR24-MoB3 are thermodynamically more favorable than MoB3 in other structures. A pressure-induced phase transition is predicted at 13 GPa from hP16-MoB3 and hR24-MoB3 to hP4-MoB3. Above 13 GPa, hP4-MoB3 becomes the thermodynamically most stable phase among MoB3 in considered structures. All compounds with considered structures are metallic, and the electronic structures of MB3 are governed by a strong hybridization between M-4d and B-2p states. The strong and directional covalent bonding between M-4d and B-2p as well as the strong interlayer interactions of boron layers are correlated to the high hardness of 38.0 and 38.4 GPa for hP16-MoB3 and hR24-MoB3, respectively.

scholarly journals Humik Asit Üretiminde Kullanılan Karıştırıcıların Kaotik Sistemler İle Performanslarının İyileştirilmesi

2021 ◽  
Vol 9 (3) ◽  
pp. 508-514
Author(s):  
Onur Kalaycı ◽  
İhsan Pehlivan ◽  
Selçuk Coşkun
Keyword(s):  
Humic Acid ◽  
Product Quality ◽  
Chaotic Systems ◽  
Energy Savings ◽  
Dynamic Properties ◽  
Experimental Studies ◽  
Total Energy Consumption ◽  
Machine Interface ◽  
Labview Program ◽  
Time And Energy

In this study; it is aimed to increase the efficiency of the mixers in terms of important criteria such as product quality, homogeneity, time and energy saving by using chaotic systems instead of traditional mixing methods in the production of humic acid, which is one of the most widely used plant nutrition and soil conditioning products in our country and in the world. Based on these properties of chaotic systems: For experimental studies; by designing A PLC (Programmable Logic Controller) controlled mixer, whose all functions can be controlled by the HMI (Human Machine Interface) operator panel, was manufactured. In this mixer, liquid humic acid was obtained by mixing water, leonardite and potassium hydroxide (KOH). For chaotic mixing process; chaotic systems with different dynamic properties had been selected from the literature. The differential equations of these chaotic systems were solved according to the Runge Kutta 45 (RK45) numerical solution algorithm in an interface program developed in the Labview program, and the chaotic time series results of each chaotic system were obtained. By transforming those results into frequency datas with the program written on the PLC device, the mixer motor connected to the frequency inverter was provided to rotate in variable speeds according to the selected chaotic systems. By means of obtaining same mixture also with traditional methods (constant speed), the comparison was done in terms of product quality, solute ratio, pH values and total energy consumption. With respect to the derived results; it has been observed that mixing done by using chaotic systems is more efficient than traditional mixing methods in terms of criterion such as product quality, homogeneity, time and energy savings.

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