The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Phase retrieval is an iterative method that has been developed to recover the lost phase information in coherent diffraction imaging. The most widely used algorithm is the hybrid input-output (HIO) algorithm because of its ability to avoid local minimum. Unfortunately the presence of noise in the images acquired disturbs the convergence of the algorithm. A few solutions have been proposed in order...
The nature of digital hydraulic systems may cause severe fluid-borne noise problems because of the pulsed nature of the flow. An effective method to reduce the noise that does not impair the system performance and efficiency is needed. This article reports on initial investigations of an active valve for pressure pulsation attenuation in switched inertance hydraulic systems (SIHS) based on in-series...
To reduce the effect of changes in gravity field and radius on Aerospace Vehicles navigation system, an inertial navigation algorithm in launch inertial coordinate for ASV is studied in this paper firstly. To overcome the poor performance of Kalman filter in uncertain environment, an extended H∞ filtering algorithm is designed secondly. Combining the advantages of launch inertial coordinate and H∞...
Adaptive maneuvering target tracking has important significance in the field of target tracking. In this paper, we present an adaptive Kalman filtering tracking algorithm based on improved strong tracking filter (STF). By changing the structure of STF, we apply it to maneuvering target tracking. This greatly expands the range of STF's applications, effectively improves the Kalman filter's ability...
This paper presents a novel image abstraction tech- nique, the deceived bilateral filter (DBF). The DBF combines border sharpening with simplification of homogeneous regions to achieve moderate de-blurring and colour emphasis. The aim of the DBF is to remove noise of colour and shape descriptors (histograms and contours) of the blobs corresponding to football players. The experiment implemented for...
Motivated by the traditional bilateral filtering, apart from considering geometric closeness and photometric similarity, we introduce the gradient factor to form a new filter kernel. Gradient reflects to the trend of edge and texture directly. By introducing the gradient weight factor, the proposed filtering algorithm overcomes the isotropy of the traditional Gaussian function, and has the directional...
The nonlinearity of the dynamic and kinetic model becomes so high that ordinary attitude determination algorithms are not accurate enough when the satellite rotates fast, and sometimes the system state does not converge. In this paper, a new attitude determination algorithm is presented to deal with this situation. Based on minimal model error (MME) principle, the model error caused by the nonlinearity...
Intensifier Charge Couple Device (ICCD) is widely used in ultraviolet (UV) detection to amplify weak UV signal so that we can extract the target. While we amplify weak signals, inevitably the noise will also amplify. In this paper, according to the different characteristic of UV detection image, a Partial Differential Equation of Adaptive Median Filter (AMF-PDE) algorithm is proposed to process the...
This investigation develops a new data clustering technique. It is a new density-based clustering scheme by diagonal sampling and a new method of fold and rotation for enhancing data clustering performance. The proposed algorithm's expansion without selecting data points to increase computation cost and it may considerably lower time cost The experimental results confirm that the presented approach...
This paper presents a new technique for adaptive estimation of the frequency of unbalanced three-phase power systems using complex coefficient first-order notch filters. The input complex sinusoid is given by a sum of sequences with positive and negative frequencies. Analytical expressions of mean square error due to an oscillating error introduced by the sequence with negative frequency and input...
This paper presents a novel multi-frame denoising method for low light images to get a clear shot even under dark conditions. To this end, multiple short-exposure images are aligned and filtered with a temporal-spatial filter to suppress the noise. Simulation results on real low-light scenes show that the proposed method outperforms the state-of-the-art image denoising method both on processing speed...
This paper proposes an adaptation algorithm named Recursive Least Normalized Correlation Norms (RLNCN) algorithm for adaptive filters, based on a cost function of a quantity named Normalized Correlation Norm (NCN) which generically yields a family of normalized type algorithms. The RLNCN algorithm achieves a significant improvement in filter convergence speed, while it preserves robustness against...
Baseline wander removal is an unavoidable step in ECG signal processing. The in-band nature of this noise makes its removal difficult without affecting the ECG, in particular the ST segment. This portion of the ECG has high clinical relevance, as it is related to the diagnosis of acute coronary syndromes. We have recently proposed a novel approach to baseline wander removal based on the notion of...
A robust active noise controller is proposed to effectively linearize nonlinear distortions in the secondary path and be applied for attenuating the noise. In real applications, the overall active control system is nonlinear and the performance of noise attenuation is decreased by the extent of nonlinearities, so an active control system compensating nonlinear distortions is needed. Through computer...
This paper presents a new digital method to improve the performance of the ΔΣ modulator. The proposed method uses a fuzzy line enhancer (FLE) to reduce the existing noise in the output of the modulator. The simulation results show 14 dB improvements in signal to noise and distortion ratio (SNDR) by using the FLE.
This paper demonstrates the Least Mean Square (LMS) adaptive filter for adaptive noise (interference) removal. A measured signal contains an unknown signal of interest and an interference signal. The goal is to design an LMS based adaptive noise canceller that adaptively removes the maternal heartbeat signal from the fetal electrocardiogram signal. This Least Mean Square based adaptive filter will...
In this paper, we propose robust set-membership filtering algorithms against impulsive noise. Firstly, we introduce set-membership normalized least absolute difference algorithm (SM-NLAD). This algorithm provides robustness against impulsive noise through pricing the absolute error instead of the square. Then, in order to achieve comparable convergence performance in the impulse-free noise environments,...
In this paper, we use the bilateral filter to de-noise nighttime infrared monitoring images, in order that noises are reduced and edges are preserved. Considering that traditional bilateral filter does not balance gray-scale difference and the geometric distance in determining the weights of convolution kernel coefficients, we propose to give the two different values different weights, so that both...
This paper proposes a method to implement an image filtering module by using 3×3 mask on FPGA. The 3×3 mask filter module has an advantage of minimizing a usage of memory and a propagation delay from input to output. Depending on coefficient value of 3×3 mask filter module, we can acquire several image processing effects such as mean filtering, median filtering, and edge enhancement. When we applied...
Restoration of the image corrupted by impulse noise is proposed in this paper. Adaptive neuro fuzzy inference system (ANFIS) has been used to detect the impulse noisy pixels to keep preserve the fine details of the image. Feed-forward neural network with resilient backpropagation method is used to estimate the value of the pixel by which the corrupted pixel is replaced by the estimated value. Proposed...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.