To solve the problem of fault signals wind turbine bearings being weak, not easy to extract, and difficult identify, this paper proposes a diagnosis method for fan based on Complete Ensemble Empirical Mode Decomposition with Adaptive Noise (CEEMDAN) Grey Wolf Algorithm Optimization Kernel Extreme Learning Machine (GWO-KELM). First, eliminating interference noise collected vibration signal shoul...

Two uncorrelated random dot patterns were superimposed and alternated to produce dynamic incoherent noise. When a low spatial frequency sine wave grating was optically superimposed on this noise and moved in step with the alternation of the two frames, the incoherent motion was masked and all the dots were seen to adhere to the grating and to move with it as a single rigid sheet ("Motion Captur...

the mixed-signal circuits with both analog and digital blocks on a single chip have wide applications in communication and rf circuits. integrating these two blocks can cause serious problems especially in applications requiring fast digital circuits and high performance analog blocks. fast switching in digital blocks generates a noise which can be introduced to analog circuits by the common su...

different methods exists for jamming mitigation and we should choose a method based an the jammer type and other parameters. one of the jammers is narrow band fm jammer and we use subspace projection techniques for the suppression of this type of jammer. in subspace projection technique, we estimate the if of signals and construct the subspace vector that is orthogonal to jammer vector by incre...

background: speech perception ability depends on auditory and extra-auditory elements. the signal-to-noise ratio (snr) is an extra-auditory element that has an effect on the ability to normally follow speech and maintain a conversation. speech in noise perception difficulty is a common complaint of the elderly. in this study, the importance of snr magnitude as an extra-auditory effect on speech...

background and aim: with regard to the shortage of proper materials in persian for the evaluation of speech perception in children, this study aimed to develop the persian version of the bkb sentence test, and determine its content validity in normal persian speaking children aged 6-12 years. methods: this study was an applied research. the study procedure comprised sentence construction, deter...

background: the microarray technology is in needed of cost-effective, low background noise and stable substrates for successful hybridization and analysis. methods: in this research, we developed a three-dimentional stable and mechanically reliable microarray substrates by coating of two polymeric layers on standard microscope glass slides. for fabrication of these substrates, a thin film of ox...

HYPRES Superconducting MicroElectronics (SME) Technology provides unparalleled performance improvements in the digital domain allowing, for the first time, the direct digital conversion of RF signals while enabling the use of advanced ultra-high speed digital signal processing techniques. SME makes it possible to take the receive (or transmit) signal directly at the output of the base station a...

in current years, the application of biopotential signals has received a lot of attention in literature. one of these signals is an electromyogram (emg) generated by active muscles. surface emg (semg) signal is recorded over the skin, as the representative of the muscle activity. since its amplitude can be as low as 50 µv, it is sensitive to undesirable noise signals such as power‑line interfer...

The noise in reconstructed slices of X-ray Computed Tomography (CT) is of unknown distribution, non-stationary, oriented and difficult to distinguish from main structural information. This requires the development of special post-processing methods based on the local statistical evaluation of the noise component. This paper presents an adaptive method of reducing noise in CT images employing th...