The four-dimensional metric f(R) theories of gravity are cast into connection-dynamical formalism with real su(2) connections as configuration variables. Through this formalism, the classical metric f(R) theories are quantized by extending the loop quantization scheme of general relativity. Our results imply that the nonperturbative quantization procedure of loop quantum gravity is valid not on...

A modulated holding beam shining a VCSEL above threshold can improve modulation bandwidth by adjusting the semiconductor laser’s relaxation oscillation frequency. The improved modulation characteristics are accompanied by reduced damping rate. By choosing correct parameters, dynamical behavior of system and cavity solitons is changed.

the study of the dynamic behavior of a rigid body with one fixed point (gyroscope) has a long history. a number of famous mathematicians and mechanical engineers have devoted enormous time and effort to clarify the role of dynamic effects on its movement (behavior) – stable, periodic, quasi-periodic or chaotic. the main objectives of this review are: 1) to outline the characteristic features of...

We assessed the unloading effect of the patellar tendon-bearing (PTB) cast in five healthy volunteers using a new system for analysis of dynamic plantar pressure. We devised a method to improve the unloading effect of the PTB cast, and tested this using the same system. Our findings showed that the conventional PTB cast only achieved unloading of 30% of the body-weight and that the part of the ...

In this paper, first the space of hyperbolic tangent functions is introduced and then the universal approximator property of this space is proved. In fact, by using this space, any nonlinear continuous function can be uniformly approximated with any degree of accuracy. Also, as an application, this space of functions is utilized to design feedback control for a nonlinear dynamical system.

Modified gravity theories can be used for the description of homogeneous and isotropic cosmological models through corresponding field equations. These cast into systems autonomous differential equations because their sole dependence on a well-chosen time variable, it time, or an alternative. For that reason, dynamical approach offers reliable route to study those Through model-independent set ...

The problems of causality, modeling, and control for chaotic, high-dimensional dynamical systems are formulated in the language information theory. central quantity interest is Shannon entropy, which measures amount states system. Within this framework, causality quantified by flux among variables Reduced-order modeling posed as a problem related to conservation models aim at preserving maximum...

Usually mathematicians use Hodgkin-Huxley model or FitzHug-Nagumo model to simulate action potentials of skeletal muscle fibers. These models are electrically excitable, but skeletal muscle fibers are stimulated chemically. To investigate skeletal muscle fibers we use a model with six ordinary differential equations. This dynamical system is sensitive to initial value of some variables so it is...