The influence of the diamagnetic plate thickness on the stability zone in vertical static magnetic levitation

2008 ◽  
Author(s):  
Em. Cazacu ◽  
Al. Nicolae
Keyword(s):  
Magnetic Levitation ◽  
Plate Thickness ◽  
Stability Zone ◽  
The Stability

scholarly journals Gas Seeps at the Edge of the Gas Hydrate Stability Zone on Brazil’s Continental Margin

Geosciences ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 193 ◽  
Author(s):  
Marcelo Ketzer ◽  
Daniel Praeg ◽  
Maria A.G. Pivel ◽  
Adolpho H. Augustin ◽  
Luiz F. Rodrigues ◽  
...  
Keyword(s):  
Gravitational Collapse ◽  
Continental Margin ◽  
Gas Hydrate ◽  
Deep Sea ◽  
Rio Grande ◽  
Cold Seep ◽  
Stability Zone ◽  
The Stability ◽  
Sea Fan ◽  
Hydrate Stability

Gas hydrate provinces occur in two sedimentary basins along Brazil’s continental margin: (1) The Rio Grande Cone in the southeast, and (2) the Amazon deep-sea fan in the equatorial region. The occurrence of gas hydrates in these depocenters was first detected geophysically and has recently been proven by seafloor sampling of gas vents, detected as water column acoustic anomalies rising from seafloor depressions (pockmarks) and/or mounds, many associated with seafloor faults formed by the gravitational collapse of both depocenters. The gas vents include typical features of cold seep systems, including shallow sulphate reduction depths (<4 m), authigenic carbonate pavements, and chemosynthetic ecosystems. In both areas, gas sampled in hydrate and in sediments is dominantly formed by biogenic methane. Calculation of the methane hydrate stability zone for water temperatures in the two areas shows that gas vents occur along its feather edge (water depths between 510 and 760 m in the Rio Grande Cone and between 500 and 670 m in the Amazon deep-sea fan), but also in deeper waters within the stability zone. Gas venting along the feather edge of the stability zone could reflect gas hydrate dissociation and release to the oceans, as inferred on other continental margins, or upward fluid flow through the stability zone facilitated by tectonic structures recording the gravitational collapse of both depocenters. The potential quantity of venting gas on the Brazilian margin under different scenarios of natural or anthropogenic change requires further investigation. The studied areas provide natural laboratories where these critical processes can be analyzed and quantified.

Design and fabrication of a hybrid maglev model employing PML and SML

2017 ◽  
Vol 31 (25) ◽  
pp. 1745014 ◽  
Author(s):  
R. X. Sun ◽  
J. Zheng ◽  
L. J. Zhan ◽  
S. Y. Huang ◽  
H. T. Li ◽  
...  
Keyword(s):  
Permanent Magnet ◽  
Simple Structure ◽  
Magnetic Levitation ◽  
Experimental Results ◽  
Heavy Load ◽  
Passive Stability ◽  
Model Combining ◽  
Levitation System ◽  
The Stability

A hybrid maglev model combining permanent magnet levitation (PML) and superconducting magnetic levitation (SML) was designed and fabricated to explore a heavy-load levitation system advancing in passive stability and simple structure. In this system, the PML was designed to levitate the load, and the SML was introduced to guarantee the stability. In order to realize different working gaps of the two maglev components, linear bearings were applied to connect the PML layer (for load) and the SML layer (for stability) of the hybrid maglev model. Experimental results indicate that the hybrid maglev model possesses excellent advantages of heavy-load ability and passive stability at the same time. This work presents a possible way to realize a heavy-load passive maglev concept.

scholarly journals Threshold Pump Power And Stability Zone Study of A Cw Ti:sa Laser Based on Using Two Different Dielectric Broadband High Reflective Cavity Mirrors

2020 ◽  
Vol 23 (2) ◽  
pp. 70-86
Author(s):  
Awaz Adil Kareem ◽  
Diyar A. S. Sadiq Mayi
Keyword(s):  
Pump Power ◽  
Laser System ◽  
Laser Cavity ◽  
Optical Parameters ◽  
Stability Zone ◽  
Optical Components ◽  
Threshold Pump Power ◽  
Dielectric Mirror ◽  
The Stability ◽  
Stable Laser

The present work study the optical parameters for CW operation in Ti:Sapphire laser system with the focus on stability zone and threshold pump power. The main aim of this study is to explore the influence of a broadband dielectric resonator mirrors used in the laser cavity on the stability zone and threshold pump power. This effect has been determined by using two types of mirrors with different broadband reflection. The experimental results show the dependence of the stability and laser threshold pump on broadband dielectric mirrors. For a broader dielectric mirror, the stability zone shows larger stable distance with respect to the narrower mirror. Moreover, the threshold pump for the broader band is smaller than the narrower. This study allows researcher choosing the appropriate optical components for generating more stable laser with small threshold pump power.

scholarly journals Onset of Buoyancy and Surface-Tension Driven Instabilities in Presence of Random Vibrations

1990 ◽  
Vol 45 (11-12) ◽  
pp. 1235-1240
Author(s):  
B. S. Dandapat
Keyword(s):  
Surface Tension ◽  
Free Surface ◽  
Fluid Layer ◽  
Heat Conducting ◽  
Rigid Plate ◽  
Stability Zone ◽  
Random Vibrations ◽  
White Noise Process ◽  
Onset Of Convection ◽  
The Stability

AbstractOnset of thermal convection in an incompressible fluid layer bounded between a perfectly heat conducting lower rigid plate and an upper free surface is analysed when the layer is subject to random vibrations. It is shown that when the vibrations are characterized by a white noise process, they hasten the onset of convection. Further it is shown that the stability zone is demarcated by an inverted parabola in the (R, M) plane.

Research on Mechanism and Model of Cutting Chatter Based on the Cutting Parameters

2012 ◽  
Vol 479-481 ◽  
pp. 217-220
Author(s):  
Jin Hua Li ◽  
Yong Xian Liu ◽  
Hua Long Xie ◽  
Wei Wang ◽  
Bao Zhong Feng
Keyword(s):  
Cutting Force ◽  
Dynamic Theory ◽  
Cutting Parameters ◽  
Modal Parameters ◽  
Stability Zone ◽  
Cutting Depth ◽  
Cutting Force Coefficients ◽  
Depth Limit ◽  
Cutting Chatter ◽  
The Stability

According to the kinematics and dynamic theory, the regenerative cutting chatter is derived on the math and simplified within the probable range. The correlation is gained between the cutting depth limit and the spindle speed about the regenerative chatter. In Matlab, the mathematical modal is simulated based on the modal parameters, cutting parameters and cutting-force coefficients. The stability lobes are drawn in the diagram, the stability zone lies under the curve and avoid the occurrence of cutting chatter.

Study on the System Disturbance Rejection Method Used in the Gimbal Servo System of Magnetically Suspended Control Moment Gyro

2012 ◽  
Vol 588-589 ◽  
pp. 351-354
Author(s):  
Zong Sheng Wang ◽  
Jian Cheng Fang ◽  
Xiu Zhi Meng
Keyword(s):  
High Speed ◽  
Magnetic Levitation ◽  
Angular Rate ◽  
Servo System ◽  
Significant Inhibition ◽  
Friction Torque ◽  
Detection Circuit ◽  
The Stability ◽  
The Impact ◽  
Disturbance Torque

In order to suppress the impact of the friction torque and the magnetic levitation high-speed rotor system on the stability of gimbal servo system output angular rate, a self-adaption compensation method with no modeling for disturbance torque is presented. The interference suppressor calculates the disturbance compensation based on the torque motor current and the angular rate measured real-time by the current detection circuit and the frame angular detection circuit in the gimbal servo system, then feedbacks to the frame servo system controller to regulating the torque motor output current. 500Hz and 50Hz sinusoidal disturbance torque are introduced into the system to test the role of the interference suppressor. The result proves the interference suppressor has the same significant inhibition of effect for disturbance torque of different frequencies by MATLAB simulating framework output angular rate waveform.

scholarly journals "Study of effect of the inductor on dynamical behavior for electronic circuit by using nonlinear part from type memductance

2021 ◽  
Vol 8 (1) ◽  
pp. 98-108
Author(s):  
Abo-Talib .Y. Abbas
Keyword(s):  
Hopf Bifurcation ◽  
Phase Portrait ◽  
Bifurcation Diagram ◽  
Electronic Circuit ◽  
Dynamical Behavior ◽  
Stability Zone ◽  
Nonlinear Part ◽  
Bifurcation Line ◽  
Stability Maps ◽  
The Stability

"The effect of the coil on the dynamical behavior of the electronic circuit with nonlinear part memductance was studied, where we studied four coil values: L = 90mH, L = 80mH, L = 70mH and L = 100mH with changing the value of the first capacitance c1. We obtained stability maps consisting of two regions (the dynamical behavior zone and the stability zone), where the dividing line is the Hopf bifurcation line, as well as the bifurcation diagram for each value from the coil and the first capacitance was obtained, as well as the phase portrait diagram in which we obtained the chaotic attractions And the period of the first, second, third, fourth, fifth, sixth and eighth.

scholarly journals Model predictive control of magnetic levitation system

2020 ◽  
Vol 10 (6) ◽  
pp. 5802
Author(s):  
Lafta E. Jumaa Alkurawy ◽  
Khalid G. Mohammed
Keyword(s):  
Model Predictive Control ◽  
Predictive Control ◽  
Controller Design ◽  
Magnetic Levitation ◽  
Lagrange Function ◽  
Sufficient Conditions ◽  
Nonlinear Controller ◽  
Levitation System ◽  
Magnetic Levitation System ◽  
The Stability

In this work, we suggest a technique of controller design that applied to systems based on nonlinear. We inform the sufficient conditions for the stability of closed loop system. The asymptotic stability of equilibrium and the nonlinear controller can be applied to improvement the stability of Magnetic Levitation system(MagLev). The MagLev nonlinear nodel can be obtained by state equation based on Lagrange function and Model Predictive Control has been used for MagLev system.

The Reliability Of Watertight Longitudinal Girders Of Fuel Tanks On Aging Bulk Carriers

2021 ◽  
Vol 93 (6s) ◽  
pp. 175-185
Author(s):  
Špiro Ivošević ◽  
◽  
Nataša Kovač ◽  
Keyword(s):  
Plate Thickness ◽  
Steel Plates ◽  
Structural Elements ◽  
Operational Conditions ◽  
Metal Plates ◽  
Bulk Carriers ◽  
Fuel Tanks ◽  
Failure Intensity ◽  
Longitudinal Strength ◽  
The Stability

During the exploitation of bulk carriers, the condition of structural elements and areas depends on the type of the cargo transported, operational conditions and maintenance systems. Corrosion significantly accelerates the aging of metal plates and girders thus causing the deterioration of steel surfaces, which consequently reduces the reliability of structural elements, areas and ships in general. The damage to metal structures can impair the stability of a ship, reduce longitudinal strength, cause the ingress of water into the hull as well as environmental pollution through fuel spills from the tanks. Therefore, the paper analyzes a part of a double bottom structure based on the available wear data on watertight longitudinal girders of fuel tanks. The research included 25 bulk carriers aged between 5 and 25 with the total of 110 fuel tanks. The reliability analysis of steel plates included the total of 1920 data measured. The allowable wear of structural plate thickness that equals 20% of the original thickness value was determined by the application of the acceptance criteria that were prescribed by classification societies. The calculations of the function of failure density, failure intensity and reliability determined the time when the condition of structural elements deteriorates due to corrosion up to the levels that require extensive maintenance services.

Sign in / Sign up

Export Citation Format

Share Document