Multimodel approach: Validities' computation by local criterion optimization

2017 ◽  
Author(s):  
Abdennacer Ben Messaoud ◽  
Samia Talmoudi Ben Aoun ◽  
Moufida Lahmari Ksouri
Keyword(s):  
Local Criterion

A Research on Navigation Star Catalog Selection Algorithm Based on SVM

2013 ◽  
Vol 706-708 ◽  
pp. 613-617
Author(s):  
Fu Cheng Liu ◽  
Zhao Hui Liu ◽  
Wen Liu ◽  
Dong Sheng Liang ◽  
Kai Cui ◽  
...  
Keyword(s):  
Support Vector Machine ◽  
Field Of View ◽  
Support Vector ◽  
Selection Algorithm ◽  
Boltzmann Entropy ◽  
Local Criterion ◽  
Star Catalog ◽  
Uniform Sampling ◽  
Global Criterion ◽  
Small Capacity

A navigation star catalog (NSC) selection algorithm via support vector machine (SVM) is proposed in this paper. The sphere spiral method is utilized to generate the sampling boresight directions by virtue of obtaining the uniform sampling data. Then the theory of regression analysis methods is adopted to extract the NSC, and an evenly distributed and small capacity NSC is obtained. Two criterions, namely a global criterion and a local criterion, are defined as the uniformity criteria to test the performance of the NSC generated. Simulations show that, compared with MFM, magnitude weighted method (MWM) and self-organizing algorithm(S-OA), the Boltzmann entropy (B.e) of SVM selection algorithm (SVM-SA) is the minimum, to 0.00207. Simultaneously, under the conditions such as the same field of view (FOV) and elimination of the hole, both the number of guide stars (NGS) and standard deviation (std) of SVM-SA is the least, respectively 7668 and 2.17. Consequently, the SVM-SA is optimal in terms of the NGS and the uniform distribution, and has also a strong adaptability.

A global and a local criterion in defining the tidal radius

2003 ◽  
Vol 324 (5) ◽  
pp. 491-505 ◽  
Author(s):  
R. Caimmi ◽  
L. Secco
Keyword(s):  
Local Criterion

A new non-local criterion in high-cycle multiaxial fatigue for non-proportional loadings

2007 ◽  
Vol 29 (8) ◽  
pp. 1465-1474 ◽  
Author(s):  
A CHAMAT ◽  
M ABBADI ◽  
J GILGERT ◽  
F COCHETEUX ◽  
Z AZARI
Keyword(s):  
Multiaxial Fatigue ◽  
Local Criterion ◽  
Non Local

A new local criterion for the lattice property

1994 ◽  
Vol 31 (4) ◽  
pp. 608-610 ◽  
Author(s):  
G�nter M. Ziegler
Keyword(s):  
Local Criterion ◽  
Lattice Property

Freak wave statistics on collinear currents

2009 ◽  
Vol 637 ◽  
pp. 267-284 ◽  
Author(s):  
KARINA B. HJELMERVIK ◽  
KARSTEN TRULSEN
Keyword(s):  
Wave Height ◽  
Significant Wave Height ◽  
Constant Current ◽  
Local Criterion ◽  
Freak Waves ◽  
Freak Wave ◽  
Significant Wave ◽  
Wave Statistics ◽  
Global Criterion ◽  
Wave Distribution

Linear refraction of waves on inhomogeneous current is known to provoke extreme waves. We investigate the effect of nonlinearity on this phenomenon, with respect to the variation of significant wave height, kurtosis and occurrence of freak waves. Monte Carlo simulations are performed employing a modified nonlinear Schrödinger equation that includes the effects of a prescribed non-potential current. We recommend that freak waves should be defined by a local criterion according to the wave distribution at each location of constant current, not by a global criterion that is either averaged over, or insensitive to, inhomogeneities of the current. Nonlinearity can reduce the modulation of significant wave height. Depending on the configuration of current and waves, the kurtosis and probability of freak waves can either grow or decrease when the wave height increases due to linear refraction. At the centre of an opposing current jet where waves are known to become large, we find that freak waves should be more rare than in the open ocean away from currents. The largest amount of freak waves on an opposing current jet is found at the jet sides where the significant wave height is small.

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