Noether gauge symmetries of geodesic motion in stationary and nonstatic Gödel-type spacetimes

2015 ◽  
Vol 38 ◽  
pp. 1560072 ◽  
Author(s):  
Ugur Camci
Keyword(s):  
Equations Of Motion ◽  
Complete Characterization ◽  
First Integrals ◽  
Geodesic Motion ◽  
Geodesic Equations ◽  
Gauge Symmetries ◽  
Geodesic Equations Of Motion

In this study, we obtain Noether gauge symmetries of geodesic motion for geodesic Lagrangian of stationary and nonstatic Gödel-type spacetimes, and find the first integrals of corresponding spacetimes to derive a complete characterization of the geodesic motion. Using the obtained expressions for [Formula: see text] of each spacetimes, we explicitly integrate the geodesic equations of motion for the corresponding stationary and nonstatic Gödel-type spacetimes.

scholarly journals On the Integrability of a Tritrophic Food Chain Model

2010 ◽  
Vol 10 (2) ◽  
Author(s):  
Jaume Llibre ◽  
Clàudia Valls
Keyword(s):  
Food Chain ◽  
Formal Series ◽  
Complete Characterization ◽  
First Integrals ◽  
Chain Model ◽  
Darboux Polynomials ◽  
Analytic First Integrals ◽  
Exponential Factors ◽  
Food Chain Model

AbstractIn this paper we work with a vastly analyzed tritrophic food chain model. We provide a complete characterization of their Darboux polynomials and of their exponential factors. We also show the non-existence of polynomial first integrals, of rational first integrals, of local analytic first integrals in a neighborhood of the origin, of first integrals that can be described by formal series and of Darboux first integrals.

scholarly journals DIRAC ANALYSIS AND INTEGRABILITY OF GEODESIC EQUATIONS FOR CYLINDRICALLY SYMMETRIC SPACETIMES

2003 ◽  
Vol 12 (08) ◽  
pp. 1431-1444 ◽  
Author(s):  
UGUR CAMCI
Keyword(s):  
Symplectic Structure ◽  
Equations Of Motion ◽  
First Order ◽  
Geodesic Equations ◽  
Cylindrically Symmetric ◽  
Symmetric Spacetimes ◽  
Constraint Analysis ◽  
Stationary Spacetime ◽  
Cylindrically Symmetric Spacetimes ◽  
Geodesic Equations Of Motion

Dirac's constraint analysis and the symplectic structure of geodesic equations are obtained for the general cylindrically symmetric stationary spacetime. For this metric, using the obtained first order Lagrangian, the geodesic equations of motion are integrated, and found some solutions for Lewis, Levi-Civita, and Van Stockum spacetimes.

Nonlinear Controller Design for Hypersonic Vehicles Based on Dynamic Inversion Considering Flexible States

2012 ◽  
Vol 424-425 ◽  
pp. 701-708 ◽  
Author(s):  
Ze Cheng ◽  
Peng Xue ◽  
Yan Li Liu
Keyword(s):  
Controller Design ◽  
Equations Of Motion ◽  
Complete Characterization ◽  
Model Parameters ◽  
Dynamic Inversion ◽  
Internal Dynamic ◽  
Nonlinear Controller ◽  
Flight Path Angle ◽  
Adaptive Fuzzy System

This paper describes a nonlinear adaptive dynamic inversion controller for a flexible air-breathing hypersonic vehicle model. The complete characterization of the nonlinear internal dynamic of the Bolender and Doman model with respect to velocity，altitude and angle as the regulated outputs is considered in this paper. The derivation of the internal dynamics presented in this work is comprehensive of the flexible dynamics. For the purpose of control design，we decompose the equations of motion into functional subsystems，namely，the velocity subsystem，the altitude and flight-path angle subsystem，and the angle of attack and pitch rate subsystem. Each subsystem is controlled separately using available inputs and intermediate virtual control commands. The adaptive fuzzy system is then developed to identify the uncertain in the model parameters. Simulation results are provided to demonstrate the robustness and the efficacy of the proposed controller

Rikitake system: analytic and Darbouxian integrals

2005 ◽  
Vol 135 (6) ◽  
pp. 1309-1326 ◽  
Author(s):  
Claudia Valls
Keyword(s):  
Electromagnetic Field ◽  
Complete Characterization ◽  
First Integrals ◽  
Rikitake System

We give a complete characterization of the analytic and Darbouxian first integrals of the Rikitake system, which serves as a model for the reversal of polarity of the Earth's electromagnetic field. Our approach uses the Darboux theory of integrability.

Experimental Characterization of Mechanical Behavior of Cord-Rubber Composites

1982 ◽  
Vol 10 (1) ◽  
pp. 37-54 ◽  
Author(s):  
M. Kumar ◽  
C. W. Bert
Keyword(s):  
Response Characteristic ◽  
Cord Compression ◽  
Complete Characterization ◽  
Strain Response ◽  
Strain Gages ◽  
Experimental Characterization ◽  
Rubber Composites ◽  
Stress Strain ◽  
Strain Data

Abstract Unidirectional cord-rubber specimens in the form of tensile coupons and sandwich beams were used. Using specimens with the cords oriented at 0°, 45°, and 90° to the loading direction and appropriate data reduction, we were able to obtain complete characterization for the in-plane stress-strain response of single-ply, unidirectional cord-rubber composites. All strains were measured by means of liquid mercury strain gages, for which the nonlinear strain response characteristic was obtained by calibration. Stress-strain data were obtained for the cases of both cord tension and cord compression. Materials investigated were aramid-rubber, polyester-rubber, and steel-rubber.

Characterization of CMOS Structures (0.6 µm process) Submitted to HBM and COM ESD Stress Tests

1997 ◽  
Author(s):  
G. Meneghesso ◽  
E. Zanoni ◽  
P. Colombo ◽  
M. Brambilla ◽  
R. Annunziata ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Electrostatic Discharge ◽  
Stress Test ◽  
Complete Characterization ◽  
Stress Tests ◽  
Test Procedures ◽  
Emission Microscopy ◽  
Fast Rise ◽  
Scanning Electron

Abstract In this work, we present new results concerning electrostatic discharge (ESD) robustness of 0.6 μm CMOS structures. Devices have been tested according to both HBM and socketed CDM (sCDM) ESD test procedures. Test structures have been submitted to a complete characterization consisting in: 1) measurement of the tum-on time of the protection structures submitted to pulses with very fast rise times; 2) ESD stress test with the HBM and sCDM models; 3) failure analysis based on emission microscopy (EMMI) and Scanning Electron Microscopy (SEM).

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