The main objective of this chapter is to present the contemporary approaches to the steganography/data hiding applications, which are based on image histogram modifications. An image histogram is a type of histogram acting as a graphical representation of the tonal distribution in a digital image. The stego images that are produced by using such data hiding techniques are inherently robust agai...

We consider nonstandard photons from nonbirefringent modified Maxwell theory and discuss their propagation in a fixed Schwarzschild spacetime background. This particular modification of Maxwell theory is Lorentz-violating and allows for maximal photon velocities differing from the causal speed c, defined as the velocity of gravitational waves over the given background space-time. In the limit o...

ARTMAP based architectures have several desirable properties that make them very suitable for pattern classification problems. However, they suffer from category proliferation. Distributed coding has been proposed as a solution for memory compression. dARTMAP neural network has been introduced as a modification of Fuzzy ARTMAP that, due to distributed learning, achieves code compression while f...

We present a simple technique to improve the perception of an object’s shape. Bump mapping is well known in the computer graphics community for providing the impression of small-scale geometrical features, which are not explicitly modelled. Here, we propose a similar approach (variation of normals) for the purpose of enhancing the perception of a given geometry. Our approach is based on a simpl...

For the Dirac particle in the rotational system, the rotation induced inertia effect is analogously treated as the modification of the “spin connection” on the Dirac equation in the flat spacetime, which is determined by the equivalent tetrad. From the point of view of parallelism description of spacetime, the obtained torsion axial-vector is just the rotational angular velocity, which is inclu...

We consider nonstandard photons from nonbirefringent modified Maxwell theory and discuss their propagation in a fixed Schwarzschild spacetime background. This particular modification of Maxwell theory is Lorentz-violating and allows for maximal photon velocities differing from the causal speed c of the asymptotic background spacetime. In the limit of geometrical optics, light rays from modified...

In this paper, we perform a detailed study of the spectral response of the gold U-shaped nano-structures for different geometrical parameters and polarizations in order to obtain significant localization factor in the wavelength 1.55 μm. The obtained near-field distribution of electric fields reveals that resonances in these nano-structures correspond to the even and odd plasmonic modes dependi...

In this paper, numerical solution of beta-type Stirling engine was presented considering its non-ideal regenerator. To this end, the second-order model including heat and power losses was used. Then, a numerical code was applied for calculating geometrical and physical optimum values of the engine. To confirm the obtained results, the physical and geometrical parameters of the GPU-3 engine were...

Weld area and weld depth/width ratio can be considered to be of the most important geometrical factors in pulsed laser welding. The effects of carbon dioxide and oxygen additions to the argon shielding gas on the weld properties in pulsed laser welding of low carbon steel is investigated. Presence of carbon dioxide and oxygen up to 10 and 15 percent respectively decreases the weld geometrical f...

The parameter space of neural networks has a Riemannian metric structure. The natural Riemannian gradient should be used instead of the conventional gradient, since the former denotes the true steepest descent direction of a loss function in the Riemannian space. The behavior of the stochastic gradient learning algorithm is much more effective if the natural gradient is used. The present paper ...