Wyniki wyszukiwania - BazTech

1

Ocena wpływu rozkładu zakłóceń stanu na dokładność estymacji wybranych algorytmów nieliniowej filtracji w systemach pozycjonujących

Konatowski S., Kaniewski P.

TTS Technika Transportu Szynowego

|

2012

|

R. 19, nr 9

979--986, CD

PL

W artykule opisane zostały algorytmy filtracji nieliniowej (rozszerzona Kalmana, bezśladowa Kalmana, cząstkowa, cząstkowa wykorzystująca filtrację rozszerzoną Kalmana oraz bezśladowa filtracja cząstkowa) stosowane w systemach pozycjonujących. Zaprezentowane zostały wyniki badań symulacyjnych porównujących jakość estymacji analizowanych rodzajów filtrów nieliniowych dla różnych nieliniowości oraz rozkładów prawdopodobieństwa zakłóceń stanu: Gaussa, Rayleigha, Studenta, i Gamma.

EN

The paper describes several types of nonlinear filtering algorithms, widely used in positioning systems (Extended Kalman Filter, Unscented Kalman Filter, particle filter, EKF approximation for particle filter and unscented particle filter). Numerous simulation results, which are to compare the quality of analyzed nonlinear filters for different nonlinearities and distributions (Gaussian, Rayleigh, Student, Gamma) are shown.

2

A power-efficient, current-mode, binary-tree min / max circuit for Kohonen self-organizing feature maps and nonlinear filters

Długosz R., Talaśka T.

Przegląd Elektrotechniczny

|

2010

|

R. 86, nr 11a

237-241

EN

A novel current-mode, binary-tree Min / Max circuit for application in analog neural networks and filters has been presented. In the proposed circuit input currents are first converted to step signals with equal amplitudes and different delays that are proportional to the values of these currents. In the second step these delays are compared using a set of time domain comparators in the binary tree structure that determine Min or Max signal. The circuit realized in the CMOS 0.18 žm process offers a precision of 99.5% at data rate of 2.5 MS/s and energy of 0.5 pJ per input.

PL

W pracy zaproponowano nowy, pracujący w trybie prądowym układ Min / Max oparty na strukturze drzewa binarnego, do zastosowań w analogowych sieciach neuronowych oraz filtrach nieliniowych. W układzie tym sygnały prądowe najpierw zamieniane są na sygnały skoku jednostkowego o równych amplitudach i różnych opóźnieniach. Następnie opóźnienia te porównywane są w komparatorach czasu znajdujących się w strukturze drzewa binarnego wskazującej sygnał o minimalnej lub maksymalnej wartości. Układ zaprojektowany w technologii CMOS 0.18 žm charakteryzuje się precyzją działania na poziomie 99.5 %, przy szybkości przetwarzania danych 2.5 MS/s oraz energii 0.5 pJ na każde wejście.

3

Nonlinear image processing and filtering: a unified approach based on vertically weighted regression

Rafajłowicz E., Pawlak M., Steland A.

International Journal of Applied Mathematics and Computer Science

|

2008

|

Vol. 18, no 1

49-61

EN

A class of nonparametric smoothing kernel methods for image processing and filtering that possess edge-preserving properties is examined. The proposed approach is a nonlinearly modified version of the classical nonparametric regression estimates utilizing the concept of vertical weighting. The method unifies a number of known nonlinear image filtering and denoising algorithms such as bilateral and steering kernel filters. It is shown that vertically weighted filters can be realized by a structure of three interconnected radial basis function (RBF) networks. We also assess the performance of the algorithm by studying industrial images.

4

Genetic filters for video noise reduction

Szostakowski J.

Machine Graphics and Vision

|

2006

|

Vol. 15, No. 3/4

631-638

EN

This paper describes a genetic programming approach to video filtering, based on evolution programming for image sequence filter design. Each gene represents a filter weight. The intra- and interframe approaches are shown and discussed.

5

Optimization analysis of rank conditioned rank selection filters

Lukac R.

Journal of Applied Computer Science

|

2004

|

Vol. 12, nr 1

23-42

EN

This paper focuses on she optimization analysis and robustness of a nonlinear filtering class of rank conditioned rank selection (RCRS) filters. which combine the general framework of rank selection filters and rank-order information on the selected input samples. Using the rank selection filter strategy, the output sample is restricted to be an order-statistic from the input set spawned by a sliding filtering window, while the number (known as the order of the filter) and file configuration of selected samples are used to extract she rank-order information lo determine the output ranked sample. By simple varying of the order and configuration of selected samples, the RCRS filler can be designed to perform a number of smoothing operations. As shown in this paper, the order and the configuration of the filter parameters influence the filter robustness, whereas the norm of the optimization criteria affects the RCRS filters in terms of a balance between noise attenuation and detail preserving characteristics.

6

A family of efficient nonlinear filters for video restoration

Abbas J., Domański M.

Machine Graphics and Vision

|

2000

|

Vol. 9, No. 1/2

353-361

EN

The paper deals with denoising of color video sequences using median-based filters. The filters emply a simple structure with nonlinear predictor and prediction error processed by a static (memoryless) noninear element. The basic idea is to predict a pixel value by using a nonlinear filter, and then to compare this value to that in the input (Corrupted) image. Usually these two values are different and a decision has to be made about the pixel value at the filter output. This value can be considered as a sum of the prediction errors are set to zero because they are can be classifield as caused by impulsive noise samples. Soft decisions on classification of prediction errors lead to good results for test images. The filters are very suitable for impulsive noise removal from color images. Preservation of textures and fine details are adventages of the filters proposed. The experimental data prove that these filters outperform classic nonlinear median-based filters like vector median, recursive median and weighted median. In the paper, it is proven that application of prediction error processing results in improved efficiency of video restoration.