It is well-known that the modelization of interactions in Continuum Physics deals with set functions associated with physical quantities rather than with functions evaluated at single points (see e.g. [7]). Very important examples of these are the stress and the heat flux. This, in turn, implies that the concept of subbody of a material body B has to be taken into account. However, subbodies ar...

An empirical approach for the retrieval of nitrogen dioxide (NO2) and formaldehyde (HCHO) photolysis frequencies from measurements of global irradiance is presented in this work. Four months of synchronous measurements of actinic flux and global irradiance performed in Thessaloniki, Greece by a Bentham spectroradiometer were used to extract polynomials for the conversion of global irradiance to...

When utilizing a finite volume method to predict outburst flood evolution in real geometry, the processing of wet-dry front and dry cells is an important step. In this paper, we propose new approach process cells, including four steps: (1) estimating intercell properties; (2) modifying interface elevation; (3) calculating cell elevations by averaging elevations; (4) changing value first term sl...

We consider application of higher-order schemes to the Boltzmann model equations with a goal to develop a deterministic computational approach that is accurate and efficient for simulating flows involving a wide range of Knudsen numbers. The kinetic equations are solved for two non-equilibrium flow problems, namely, the structure of a normal shock wave and an unsteady two-dimensional shock tube...

The error probability achieved by a differential detector with a bandpass limiter preceding the receiver is analyzed for a slow-frequency-hopped CPFSK diversity waveform transmitted over a partial-band noise jamming channel, and is compared to the system’s performance without the bandpass limiter. The system’s thermal noise is not neglected in the analysis. In principle, each bit is repeated on...

The basic concept of multi-dimensional limiting process (MLP) on unstructured grids is inherited and modified for improving shock stabilities and reducing numerical dissipation on smooth regions. A relaxed version of MLP condition, simply named as weak-MLP, is proposed for reducing dissipation. Moreover, a stricter condition, that is the strict-MLP condition, is proposed to enhance the numerica...

In this paper, we adapt a simple weighted essentially non-oscillatory (WENO) limiter, originally designed for discontinuous Galerkin (DG) schemes [42], to the correction procedure via reconstruction (CPR) framework for solving conservation laws. The objective of this simple WENO limiter is to simultaneously maintain uniform high order accuracy of the CPR framework in smooth regions and control ...

The status of the HEGRA imaging air Cherenkov telescopes is summarized. We present results from a survey of the Galactic plane for point sources with a limiting flux of approximately a third of the flux seen from the Crab Nebula. For Mkn 421 (z = 0.031) we present the detection of spectral variability correlated with the flux. Finally, we summarize results of observations carried out on the mos...

This paper is concerned with the development of general-purpose algebraic flux correction schemes for continuous (linear and multilinear) finite elements. In order to enforce the discrete maximum principle (DMP), we modify the standard Galerkin discretization of a scalar transport equation by adding diffusive and antidiffusive fluxes. The result is a nonlinear algebraic system satisfying the DM...