The aim was to develop a path-flow analysis model for young swimmers' performance based on biomechanical and energetic parameters, using structural equation modeling. Thirty-eight male young swimmers served as subjects. Performance was assessed by the 200-m freestyle event. For biomechanical assessment the stroke length, the stroke frequency and the swimming velocity were analyzed. Energetics a...

we review various ways to express the partition function of the single-band hubard model as a path integral. the emphasis is made on the derivation of the action in the integrand of the path integral and the results obtained from this approach are discussed only briefly.   since the single-band hubbard model is a pure fermionic model on the lattice and its hamiltonian is a polynomial in creatio...

The article applies a new approach to microminiaturization of the VHF radio path with significant improvement its main characteristics based on acoustoelectronic elements SAW. In particular, instead intermediate frequency filter (IF), which in most cases is implemented help "coil " products (LC circuits), CSF (concentrated selection filter) proposed be characteristic curve, and same traditional...

X-parameters are developed as a superset of S-parameters and they are suitable for modeling systems having only radio-frequency (RF) and DC ports. For a polar power amplifier (PA), the envelope of the input modulated signal is applied at the envelope port, which is neither an RF nor a DC port. In this case, X-parameter may fail to characterize the behavior of the envelope path and consequently ...

in this paper the reflection coefficient of electromagnetic wave incidence on the walls of the buildings and obstacles that occurs in mobile communication path was modified by solving the riccati nonlinear equations. for this purpose, the building walls are assumed inhomogeneous layers where their permittivity changes as function of the wall thickness. using this reflection coefficient, a new p...

The propagation path loss models may give different results if they are used in different environments other than in which they were designed. In this paper we compare the different path loss propagation models with measured field data and find out the model which is giving results nearer to the field measured data. In this we used many path loss models For comparative analysis. The field measu...

-Radio Frequency (RF) propagation is the study of how radio waves broadcast over distances. One of the main problems in mobile radio communication is the loss of propagated RF signal power at the receiver due to fading. When the fading is very strong, the signal is blocked. Modeling of the signal propagation loss is an important element of the design and performance analysis of wireless communi...