scholarly journals On resolution of the method of directional magnetotelluric soundings

2015 ◽  
Vol 1 (4) ◽  
pp. 82-85
Author(s):  
Михаил Савин ◽  
Mihail Savin
Keyword(s):  
Field Measurement ◽  
Measurement Errors ◽  
Prediction Modeling ◽  
Mathematical Experiment ◽  
Magnetotelluric Soundings ◽  
Geoelectric Model ◽  
Stability Of Solution ◽  
Abrupt Changes ◽  
The Stability ◽  
Electric Mode

The problem is to examine the resolution of directional magnetotelluric soundings (DMTS). Abrupt changes of impedances of electrical and magnetic types in critical region of parameters R~0, J~ωµσ are shown to result in significantly higher resolution of the method as compared with the traditional interpretation using Tikhonov–Cagniard impedance. The stability of solution of DMTS method inverse problem is considered subject to field measurement errors limited the resolution. The minimum of the limits is determined for the conductivity ∆σ/σ small variations. For studying DMTS resolution as applied to MT monitoring of earthquake site the mathematical experiment for three-layer geoelectric model was carried out. When changing the earthquake site conductivity of ∆σ~±10 % variations of reflection coefficient of electric mode are in the range of 20 % that is significantly more than the field measurement error. The possibility for prediction modeling in the context of obtained results is discussed.

Vehicle Lateral Motion Control Based on Estimated Stability Regions

2017 ◽  
Author(s):  
Yiwen Huang ◽  
Yan Chen
Keyword(s):  
Measurement Errors ◽  
Local Stability ◽  
Stability Region ◽  
Control Method ◽  
Linearization Method ◽  
Stability Control ◽  
Lateral Stability ◽  
Shortest Distance ◽  
The Stability ◽  
Yaw Moment

This paper presents a novel vehicle lateral stability control method based on an estimated lateral stability region on the phase plane of vehicle yaw rate and lateral speed, which is obtained through a local linearization method. Since the estimated stability region does not only describe vehicle local stability, but also define the oversteering and understeering characteristics, the proposed control method can achieve both local stability and vehicle handling stability. Considering the irregular geometric shape of the estimated stability region, a stability analysis algorithm is designed to determine the distance between vehicle states and stability region boundaries. State estimation or measurement errors are also incorporated in the distance calculation. Based on the calculated shortest distance between vehicle states and stability boundaries, a direct yaw moment controller is designed to maintain vehicle states stay within the stability region. CarSim® and Simulink® co-simulation is applied to verify the control design through a cornering maneuver. The simulation results show that the proposed control method can make the vehicle stay within the stability region successfully and thus always operate in a safe manner.

scholarly journals Stellar scattering and the formation of exponential discs in self-gravitating systems

2020 ◽  
Vol 499 (2) ◽  
pp. 2672-2684
Author(s):  
Jian Wu ◽  
Curtis Struck ◽  
Elena D’Onghia ◽  
Bruce G Elmegreen
Keyword(s):  
Velocity Dispersion ◽  
Stellar Orbits ◽  
Poisson Equations ◽  
Abrupt Changes ◽  
Gradient Solution ◽  
Stellar Velocity ◽  
Zero Entropy ◽  
Profile Changes ◽  
The Stability ◽  
Gravitating Systems

ABSTRACT We show, using the N-body code gadget-2, that stellar scattering by massive clumps can produce exponential discs, and the effectiveness of the process depends on the mass of scattering centres, as well as the stability of the galactic disc. Heavy, dense scattering centres in a less stable disc generate an exponential profile quickly, with a time-scale shorter than 1 Gyr. The profile evolution due to scattering can make a near-exponential disc under various initial stellar distributions. This result supports analytic theories that predict the scattering processes always favour the zero entropy gradient solution to the Jeans/Poisson equations, whose profile is a near-exponential. Profile changes are accompanied by disc thickening, and a power-law increase in stellar velocity dispersion in both vertical and radial directions is also observed through the evolution. Close encounters between stars and clumps can produce abrupt changes in stellar orbits and shift stars radially. These events can make trajectories more eccentric, but many leave eccentricities little changed. On average, orbital eccentricities of stars increase moderately with time.

A solution-processable host material of 1,3-bis{3-[3-(9-carbazolyl)phenyl]-9-carbazolyl}benzene and its application in organic light-emitting diodes employing thermally activated delayed fluorescence

2015 ◽  
Vol 3 (8) ◽  
pp. 1700-1706 ◽  
Author(s):  
Yoshitake Suzuki ◽  
Qisheng Zhang ◽  
Chihaya Adachi
Keyword(s):  
Light Emitting Diodes ◽  
High Mobility ◽  
Delayed Fluorescence ◽  
Organic Light Emitting Diodes ◽  
Thermally Activated Delayed Fluorescence ◽  
Light Emitting ◽  
Thermally Activated ◽  
Stability Of Solution ◽  
Organic Light ◽  
The Stability

The stability of solution-processed organic light-emitting diodes employing a thermally activated delayed fluorescent emitter was improved using a host with a high glass transition temperature and high mobility electron transport layers.

scholarly journals A New Data-Driven Control System for MEMSs Gyroscopes: Dynamics Estimation by Type-3 Fuzzy Systems

Micromachines ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1390
Author(s):  
Khalid A. Alattas ◽  
Ardashir Mohammadzadeh ◽  
Saleh Mobayen ◽  
Ayman A. Aly ◽  
Bassem F. Felemban ◽  
...  
Keyword(s):  
Fuzzy System ◽  
Measurement Errors ◽  
Fuzzy Systems ◽  
Data Driven ◽  
Output Data ◽  
Data Set ◽  
Control Scheme ◽  
Mems Gyroscopes ◽  
The Stability ◽  
Type 3

In this study, a novel data-driven control scheme is presented for MEMS gyroscopes (MEMS-Gs). The uncertainties are tackled by suggested type-3 fuzzy system with non-singleton fuzzification (NT3FS). Besides the dynamics uncertainties, the suggested NT3FS can also handle the input measurement errors. The rules of NT3FS are online tuned to better compensate the disturbances. By the input-output data set a data-driven scheme is designed, and a new LMI set is presented to ensure the stability. By several simulations and comparisons the superiority of the introduced control scheme is demonstrated.

scholarly journals Well-posed conditions on a class of fractional q-differential equations by using the Schauder fixed point theorem

2021 ◽  
Vol 2021 (1) ◽  
Author(s):  
Mohammad Esmael Samei ◽  
Ahmad Ahmadi ◽  
A. George Maria Selvam ◽  
Jehad Alzabut ◽  
Shahram Rezapour
Keyword(s):  
Fixed Point ◽  
Fixed Point Theorem ◽  
Differential Equations ◽  
Point Theorem ◽  
Schauder Fixed Point Theorem ◽  
Stability Of Solution ◽  
The Stability ◽  
Well Posed ◽  
Schauder Fixed Point ◽  
Schäuder Fixed Point Theorem

AbstractIn this paper, we propose the conditions on which a class of boundary value problems, presented by fractional q-differential equations, is well-posed. First, under the suitable conditions, we will prove the existence and uniqueness of solution by means of the Schauder fixed point theorem. Then, the stability of solution will be discussed under the perturbations of boundary condition, a function existing in the problem, and the fractional order derivative. Examples involving algorithms and illustrated graphs are presented to demonstrate the validity of our theoretical findings.

scholarly journals A Study on the Stability of Solution in the Distinct Element Method.

1998 ◽  
Vol 35 (3) ◽  
pp. 183-191
Author(s):  
Hiroaki TANAKA ◽  
Koji INOOKU ◽  
Masahiro MIYAZAKI ◽  
Yuji NAGASAKI
Keyword(s):  
Distinct Element ◽  
Distinct Element Method ◽  
Stability Of Solution ◽  
The Stability ◽  
Element Method
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