Direction-of-arrival (DOA) estimation methods for wideband linear frequency modulated (LFM) signals based on fractional Fourier transform (FRFT) typically use the single snapshot vector in (FRF) domain. However, low-rank problem of second-order statistics can decrease DOA resolution and cause issues coherent sources. In order to address these problems, a weighted l1-norm method FRFT is proposed...

IN THIS WORK, CARBON FIBRE REINFORCED POLYMER (CFRP) PLATES HAVE BEEN TESTED UNDER FREE IMPACT VIBRATION TESTS PRISTINE AND DAMAGED CONFIGURATIONS. EACH PLATE INVOLVED ONE CRACK OF SPECIFIC ORIENTATION (HORIZONTAL, VERTICAL, DIAGONAL). THE WERE SUSPENDED AS CANTILEVERS VIBRATED USING AN HAMMER. TWO ACCELEROMETERS MICROPHONE USED TO OBTAIN RESPONSE DATA SIGNALS FROM PLATES, FREQUENCY FUNCTION (F...

The most significant invention made in recent years to serve various applications is software. Developing a faultless software system requires the design be resilient. To make more efficient, it essential assess reusability of components used. This paper proposes prediction model named Flexible Random Fit (FRF) based on aging resilience for Service Net (SN) system. developed multilevel optimiza...

Regularities of a size dependence extinction and absorption efficiency factors as well near-zone far-zone scattering are studied in the spectral range surface plasmon resonance (SPRA) for silver spherical nanoparticles placed into absorbing matrixes with complex refraction index n m +ikappa . Numerical simulation was made use Mie theory matrixes. Approximation electron mean free path limitation...

Abstract—In the cellular MIMO systems, the system capacity can be increased with the presence of multi-user diversity (MUD). In this paper, a hybrid frequency reuse algorithm is proposed to realize efficient frequency reuse factor (FRF) allocation for cellular MIMO systems with MUD. As a result, the system capacity will be increased greatly. The system capacities by using the proposed algorithm...

The problem of aircraft engine condition monitoring based on vibration signals is addressed. To do so, we compare two estimators of the Frequency Response Function of an aircrat engine which input is its shaft angular position and which output is an accelerometric signal that measures vibrations. It is shown that this problem can be seen as a smoothing problem, and that linear kernel smoothing ...

This paper presents the results of experimental and numerical tests on the behaviour of radial lip seals in order to characterize a model of the effects of vibrations and working temperature. Starting validation of the numerical analysis, performed with the Finite Element Method, is obtained measuring the frequency response function (FRF) by using different excitation signals. Seal’s lip displa...

Paying attention to the spatial placement of the elements (man-made or natural) based on the landscape pattern and ecological processes in urban design would have a considerable impact on both human and the nature. In a way that the discords in the placement of patchs in respect to each other, or in respect to visual corridors and urban matrixes lead to the unwanted results in the cities. The e...

FRF based substructuring (FBS) predicts the dynamic behaviour of a coupled system on the basis of freeinterface FRFs of the uncoupled components. The modal synthesis technique determines the dynamic behaviour of a coupled system on the basis of a normal mode description of the uncoupled components. This paper gives a brief description of the theoretical background of these techniques. When usin...

Large damping levels, low signal to noise ratio, and low frequency resolution can cause difficulties for current SDOF SISO algorithms that identify natural frequency, modal damping ratio, and the residue associated with each eigenvalue. This paper offers an alternative technique that through a change of variables leads to a set of linear equations for the complex eigenvalue and residue. The app...