invariance theory
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2021 ◽  
Vol 38 (6) ◽  
pp. 1599-1611
Author(s):  
Hong Yang ◽  
Yanming Zhao ◽  
Guoan Su ◽  
Xiuyun Liu ◽  
Songwen Jin ◽  
...  

The conventional slow feature analysis (SFA) algorithm has no support of computational theory of vision for primates, nor does it have the ability to learn the global features with visual selection consistency continuity. And what is more, the algorithm is highly complex. Based on this, Slow Feature Extraction Algorithm Based on Visual selection consistency continuity and Its Application was proposed. Inspired by the visual selection consistency continuity theory for primates, this paper replaced the principal component analysis (PCA) method of the conventional SFA algorithm with the myTICA method, extracted the Gabor basis functions of natural images, initialized the basis function family; it used the feature basis expansion algorithm based on visual selection consistency continuity (the VSCC_FBEA algorithm) to replace the polynomial expansion method in the original SFA algorithm to generates the Gabor basis functions of features with long and short-term visual selectivity in the family of basis functions, which solved the drawbacks of the polynomial prediction algorithm; it also designed the Lipschitz consistency constraint, and proposed the Lipschitz-Orthogonal-Pruning-Method (LOPM algorithm) to optimize the basis function family into an over-complete family of basis functions. In addition, this paper used the feature expression method based on visual invariance theory (visual invariance theory -FEM) to establish the set of features of natural images with visual selection consistency continuity. Subsequently, it adopted three error evaluation methods and mySFA classification method to evaluate the proposed algorithm. According to the experimental results, the proposed algorithm showed good prediction performance with respect to the LSVRC2012 data set; compared with the SFA, GSFA, TICA, myICA and mySFA algorithms, the proposed algorithm is correct and feasible; when the classification threshold of the algorithm was set at 8.0, the recognition rate of the proposed algorithm reached 99.66%, and neither of the false recognition rate and the false rejection rate was higher than 0.33%. The proposed algorithm has good performance in prediction and classification, and also shows good anti-noise capacity under limited noise conditions.


Electronics ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 50
Author(s):  
Juntong Qi ◽  
Yuan Ping ◽  
Mingming Wang ◽  
Chong Wu

This study investigates the trajectory planning problem for double-pendulum quadrotor transportation systems. The goal is to restrain the hook swing and payload swing while achieving precise positioning. An online trajectory planning method with two capabilities—precise positioning and swing suppression—is proposed. The stability and convergence of the system are proved using the Lyapunov principle and the LaSalle’s invariance theory. Simulation results show that the proposed method has excellent control performance.


Author(s):  
Mohammed B. Al-Fadhli

The recent Planck Legacy release has confirmed the presence of an enhanced lensing amplitude in the cosmic microwave background power spectra, which prefers a positively curved early Universe with a confidence level greater than 99%. In addition, the spacetime curvature of the entire galaxy differs from one galaxy to another due to their diverse energy densities. This study considers both the implied positive curvature of the early Universe and the curvature across the entire galaxy as the curvature of ‘the background or the 4D bulk’ and distinguishes it from the localized curvature that is induced in the bulk by the presence of comparably smaller celestial objects that are regarded as ‘relativistic 4D branes’. Branes in different galaxies experience different bulk curvatures, thus their background or bulk curvature should be taken into consideration along with their energy densities when finding their induced curvatures. To account for the interaction between the bulk and branes, this paper presents extended field equations in terms of brane-world modified gravity consisting of conformal Einstein field equations with a boundary term, which could remove the singularities and satisfy a conformal invariance theory. A visualization of the evolution of the 4D relativistic branes over the conformal space-time of the 4D bulk is presented.


Author(s):  
Mohammed B. Al-Fadhli

The recent Planck Legacy release confirmed the presence of an enhanced lensing amplitude in the cosmic microwave background (CMB) power spectra. Notably, this amplitude is higher than that estimated by the lambda cold dark matter model (ΛCDM), which endorses a positively curved early Universe with a confidence level greater than 99%. Although General Relativity (GR) performs accurately in the local/present Universe where spacetime is almost flat, its lost boundary term, incompatibility with Quantum Mechanics and the necessity of dark matter/energy could indicate its incompleteness. By utilising the Einstein–Hilbert action, this letter presents extended field equations by considering the pre-existing/background curvature and the boundary contribution. The extended field equations consist of Einstein field equations with a conformal transformation feature in addition to the boundary term, which can remove singularities, satisfy a conformal invariance theory and facilitate its quantisation.


Author(s):  
Yao Rong ◽  
Augusto Aubry ◽  
Antonio De Maio ◽  
Mengjiao Tang

Author(s):  
Sandra Fachelli ◽  
Ildefonso Marqués-Perales ◽  
Marcelo Boado ◽  
Patricio Solís

AbstractThis chapter presents a review of the analysis of social mobility in the international sphere (Europe and Latin America), with a particular focus on the partner countries of the INCASI network. To date, few studies have linked nations whose economic and social aspects are so dissimilar.As is usual in the specialized literature, the relationship between social origin and class destination is addressed. This is done by noting the comparisons made across the geographical areas. We review the analyses that have been made of the evolution of social fluidity as well as the distance between social classes within each country and the comparisons made between them.We compare the main theories that have inspired the study of social mobility to date: modernization theory, which predicts an increase in relative mobility rates, and invariance theory, which postulates the constancy of social fluidity. Special attention is devoted to the role played by the family, the state and the market in late industrialized countries.We study the difficulties for social change, i.e. upward mobility from one class to another, as well as the likelihood of reproduction in comparative terms. To do so, we link these mechanisms with the AMOSIT model. The advances in methodology, techniques, theory and data processing are highlighted.


2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Valerii Azarskov ◽  
Anatoly Tunik ◽  
Olha Sushchenko

The design of the control systems of the inertially stabilized platforms (ISPs) as part of airborne equipment for the majority of aircraft has its peculiarity. The presence of rate gyros in the inertial measurement unit gives the possibility to measure the rotation rate of the ISP base, which is the main disturbance interfering with the ISP accuracy. Inclusion of the feedforward disturbance gain in the control law with the simplest PI feedback significantly improves the accuracy of stabilization by the invariance theory. A combination of feedback and feedforward controllers produces a synergetic effect, thus, improving ISP accuracy. This article deals with the design of the airborne ISP control systems consisting of two stages: the parametric optimization of the PI feedback control based on composite “performance-robustness” criterion and the augmentation of the obtained system with feedforward gain. To prove the efficiency of the proposed control laws, the simulation of the ISP was undertaken. We have used a simulation of the heading-hold system of the commuter aircraft Beaver and the yaw rate output of this closed-loop system we have used as a source of the disturbance. The results of modeling proved the efficiency of the proposed design method.


2020 ◽  
Author(s):  
Kumar Puran Tripathy ◽  
Pradeep Mujumdar

<p>The Intensity-Duration-Frequency (IDF) relationships are commonly used in urban hydrologic designs. A major source of uncertainty arises due to small samples of data and use of multiple GCMs, in developing the IDF for future periods. A major objective of this study is to address uncertainties in the IDF relationships for future periods, under climate change. The study proposes a Bayesian method for addressing the parameter uncertainty in the Generalized Extreme Value (GEV) distribution for the Annual Maximum Series (AMS). Uncertainties due to the use of multiple GCMs are addressed through the Reliable Ensemble Averaging (REA) method. The posterior distributions of the three parameters of GEV distribution are obtained using Markov Chain Monte Carlo (MCMC) method. Twenty-three CMIP5 GCMs with four RCPs are considered for studying the effect of climate change on the IDF relationship for the case study of Bangalore, India. Change Factor Method (CFM) is used for spatially downscaling the projected time series of precipitation and scale-invariance theory is used for temporal disaggregation. Results are compared across different CFM schemes considering multiple bin sizes. Uncertainties in design intensities are quantified through probabilistic IDF relationships.</p>


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