355 research outputs found

    An Efficient Optimal Reconstruction Based Speech Separation Based on Hybrid Deep Learning Technique

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    Conventional single-channel speech separation has two long-standing issues. The first issue, over-smoothing, is addressed, and estimated signals are used to expand the training data set. Second, DNN generates prior knowledge to address the problem of incomplete separation and mitigate speech distortion. To overcome all current issues, we suggest employing an efficient optimal reconstruction-based speech separation (ERSS) to overcome those problems using a hybrid deep learning technique. First, we propose an integral fox ride optimization (IFRO) algorithm for spectral structure reconstruction with the help of multiple spectrum features: time dynamic information, binaural and mono features. Second, we introduce a hybrid retrieval-based deep neural network (RDNN) to reconstruct the spectrograms size of speech and noise directly. The input signals are sent to Short Term Fourier Transform (STFT). STFT converts a clean input signal into spectrograms then uses a feature extraction technique called IFRO to extract features from spectrograms. After extracting the features, using the RDNN classification algorithm, the classified features are converted to softmax. ISTFT then applies to softmax and correctly separates speech signals. Experiments show that our proposed method achieves the highest gains in SDR, SIR, SAR STIO, and PESQ outcomes of 10.9, 15.3, 10.8, 0.08, and 0.58, respectively. The Joint-DNN-SNMF obtains 9.6, 13.4, 10.4, 0.07, and 0.50, comparable to the Joint-DNN-SNMF. The proposed result is compared to a different method and some previous work. In comparison to previous research, our proposed methodology yields better results

    FPGA based Identification of Frequency and Phase Modulated Signals by Time Domain Digital Techniques for ELINT Systems

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    In this paper, a decision tree algorithm based on time-domain digital technique is developed for the identification and classification of diverse radar intra-pulse modulated signals for the electronic intelligence system in real-time. This includes linear frequency modulation, non-linear frequency modulation, stepped frequency modulation and bi-phase modulation. The received signal is digitised and the instantaneous phase and high accuracy instantaneous frequency are estimated. The instantaneous amplitude is also estimated to get the start and stop of the pulse. Instantaneous parameters are estimated using a moving autocorrelation technique. The proposed algorithm is employed on the instantaneous frequency and the modulation is identified. The modulation type and modulation parameter are important for unique radar identification when similar radars are operating in a dense environment. Simulations are carried out at various SNR conditions and results are presented. The model for algorithm is developed using a system generator and implemented in FPGA. These results are compared when the proposed algorithm is used with the existing digital in-phase and quadrature-phase (DIQ) technique of instantaneous frequency and amplitude estimation

    High Accuracy Parameter Estimation for Advanced Radar Identification of Electronic Intelligence System

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    Radar identification is one of the vital operations in an electronic intelligence system. The conventional methods based on basic parameters comparison of unique identification of a radar in a cluster of similar radars, is prone to ambiguities. To meet the current tactical requirements of unique identification of a radar, the methodology needs to be based on better feature extraction, even in low SNR conditions. The paper explores a novel technique based on moving autocorrelation for the extraction of intra-pulse and inter-pulse radar parameters. Extensive simulation and empirical studies have been carried out to establish the approach to extend accurate radar parameters in noisy and low SNR conditions. The technique is found to be promising even in field data conditions. The paper describes the methodology, simulation results, FPGA implementation using system generator and resource utilisation summary

    Impact of the Fiber Distribution Characteristics on the Uniaxial Behaviour of Fiber-Reinforced Composites- An Experimental Study

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    The demand for development of fiber-reinforced composites has enhanced as the practise of integrating fibres into concrete has become prevalent over the past few decades.. The intersection zone where the fiber crossing the fracture surface and fiber distribution characteristics in the composite plays an important role in predicting the overall performance of the Fiber Reinforced Composite (FRC). To ascertain the orientation and distribution of the fibres in various FRC's, a variety of experimental methods have been proposed in the literature. This study aimed to assess the impact of fibre orientation and fibre distribution characteristics on the fresh and hardened properties of Hybrid FRC's and Hybrid Graded FRC's containing glass and steel fibres. It can be concluded that the methods adopted in this study for calculating the fiber distribution and orientation characteristics were reliable and the proposed equations were successful in predicting the uniaxial behaviour of FRC. Positive synergy was observed in the Hybrid Graded FRC specimens, which was attributed to the superior fibre distribution characteristics displayed by hybrid grading of fibres, which was rationalised by the fact that modifying the fibre distribution characteristics would affect the FRC's behaviour

    Lattice distortion and uniaxial magnetic anisotropy in single domain epitaxial (110) films of SrRuO3

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    The effects of epitaxial strain on the orthorhombic-to-triclinic lattice distortion and uniaxial magnetic anisotropy in single-domain SrRuO3 (110) films epitaxially grown on (001) SrTiO3 substrates were examined. The magnetic orientation of the film was found to be along or near the [010] direction, rotating towards the [110] perpendicular direction with decreasing temperature. The influence of the crystalline anisotropy in SrRuO3 on the uniaxial magnetic anisotropy was also examined

    Three-dimensional strain states and crystallographic domain structures of epitaxial colossal magnetoresistive La0.8Ca0.2MnO3 thin films

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    The evolution of three-dimensional strain states and crystallographic domain structures of epitaxial colossal magnetoresistive La0.8Ca0.2MnO3 films have been studied as a function of film thickness and lattice mismatch with two types of (001) substrates, SrTiO3 and LaAlO3. In-plane and out-of-plane lattice parameters and strain states of the films were measured directly using normal and grazing incidence x-ray diffraction techniques. The unit cell volume of the films is not conserved, and it exhibits a substrate-dependent variation with film thickness. Films grown on SrTiO3 substrates with thickness up to ∼250 Å are strained coherently with a pure (001)T orientation normal to the surface. In contrast, films as thin as 100 Å grown on LaAlO3 show partial relaxation with a (110)T texture. While thinner films have smoother surfaces and higher crystalline quality, strain relaxation in thicker films leads to mixed (001)T and (110)T textures, mosaic spread, and surface roughening. The magnetic and electrical transport properties, particularly Curie and peak resistivity temperatures, also show systematic variations with respect to film thickness

    Effects of film thickness and lattice mismatch on strain states and magnetic properties of La0.8Ca0.2MnO3 thin films

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    The effects of lattice strain relaxation on the crystal structure and distortion of epitaxial La0.8Ca0.2MnO3 (LCMO) films were studied with different film thicknesses and lattice mismatches and their influence on magnetic and transport properties. As the film thickness increases, strain relaxation takes place, leading to the mosaic spread, surface roughening, and formation of mixed (001) and (110) domains in LCMO films that is observed. Although the Curie temperature and the peak resistivity temperature of the films both show strong film thickness dependence, they do not show any correlation to strain states

    Effect of three-dimensional strain states on magnetic anisotropy of La0.8Ca0.2MnO3 epitaxial thin films

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    Magnetic anisotropy of La0.8Ca0.2MnO3 (LCMO) epitaxial thin films grown on (001) SrTiO3 and LaAlO3 a substrates exhibits strong correlation with substrate-induced strain states as determined by normal and grazing incidence x-ray diffraction. In a 250 Å thick LCMO (001)T film grown on SrTiO3 substrate, an in-plane biaxial magnetic anisotropy is observed, and it is accompanied by a substrate-induced in-plane biaxial tensile strain. In contrast, the observed magnetic easy axis for a 250 Å (110)T film grown on LaAlO3 substrate is perpendicular to the film plane, and the corresponding in-plane strain is biaxial compressive. In both cases the magnetic easy axes are along the crystallographic directions under tensile strain, indicating the presence of a positive magnetostriction. In thicker films (∼4000 Å) grown on both substrates that are nearly strain relaxed, the magnetic easy axis lies in the film plane along the [110] direction of the (001) substrate

    Temperature dependence of magnetic anisotropy of La0.8Ca0.2MnO3 epitaxial thin films

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    Magnetic anisotropy of epitaxial La0.8Ca0.2MnO3(LCMO) thin films grown by pulsed laser deposition has been studied as a function of temperature and lattice strain. Pseudomorphic growth on (001) SrTiO3 substrates imposes an in-plane tensile stress on the LCMO films, which produces an easy-plane magnetic anisotropy in the growth plane, accompanied by a weak biaxial anisotropy in the easy plane. In contrast growth on (001) LaAlO3 substrates produces an in-plane compressive stress, which leads to an out-of-plane uniaxial easy axis. The observed behavior indicates the presence of a positive magnetostriction, and that the anisotropy energy is dominated by the epitaxial strain induced effects. Uniaxial magnetic anisotropy constants of 250 and 500 Ã… LCMO films have been determined by fitting the magnetization curves for temperatures between 5 and 200 K, and magnetostriction constants have been estimated subsequently

    Non-Fermi liquid behavior and scaling of low frequency suppression in optical conductivity spectra of CaRuO3_3

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    Optical conductivity spectra σ1(ω)\sigma_1(\omega) of paramagnetic CaRuO3_3 are investigated at various temperatures. At T=10 K, it shows a non-Fermi liquid behavior of σ1(ω)∼1/ω12\sigma_1(\omega)\sim 1/{\omega}^{\frac 12}, similar to the case of a ferromagnet SrRuO3_3. As the temperature (TT) is increased, on the other hand, σ1(ω)\sigma_1(\omega) in the low frequency region is progressively suppressed, deviating from the 1/{\omega}^{\frac 12%}-dependence. Interestingly, the suppression of σ1(ω)\sigma_1(\omega) is found to scale with ω/T\omega /T at all temperatures. The origin of the % \omega /T scaling behavior coupled with the non-Fermi liquid behavior is discussed.Comment: 4 pages, 3 figure
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