Search results for "filter"
showing 10 items of 1019 documents
A fully-automated procedure for measuring the electrical parameters of an induction motor drive with rotor at standstill
2003
The paper presents an automatic procedure to measure at standstill the electrical parameters of an induction motor fed by a PWM voltage source inverter. The proposed procedure executes automatically three tests using only the available PWM inverter control technique to obtain the required motor supply voltages. It allows the measurement of all the T-form circuit electrical parameters starting from the nameplate data as data-entry. It uses only a current sensor and no voltage sensor and process on line the collected data samples with a fast and easy to implement recursive least squares algorithm. Effectiveness of the automated procedure has been proved both by simulation and experimental tes…
Sensorless Control of Induction-Motor Drive Based on Robust Kalman Filter and Adaptive Speed Estimation
2014
This paper deals with robust estimation of rotor flux and speed for sensorless control of motion control systems with an induction motor. Instead of using sixth-order extended Kalman filters (EKFs), rotor flux is estimated by means of a fourth-order descriptor-type robust KF, which explicitly takes into account motor parameter uncertainties, whereas the speed is estimated using a recursive least squares algorithm starting from the knowledge of the rotor flux itself. It is shown that the descriptor-type structure allows for a direct translation of parameter uncertainties into variations of the coefficients appearing in the model, and this improves the degree of robustness of the estimates. E…
Non-linear RLS-based algorithm for pattern classification
2006
A new non-linear recursive least squares (RLS) algorithm is presented in the context of pattern classification problems. The algorithm incorporates the non-linearity of the filter's output in the updating rules of the classical RLS algorithm. The proposed method yields lower stationary error levels when compared to the standard LMS and RLS algorithms in a classical application of pattern classification, such as the channel equalization problem.
Graph recursive least squares filter for topology inference in causal data processes
2017
In this paper, we introduce the concept of recursive least squares graph filters for online topology inference in data networks that are modelled as Causal Graph Processes (CGP). A Causal Graph Process (CGP) is an auto regressive process in the time series associated to different variables, and whose coefficients are the so-called graph filters, which are matrix polynomials with different orders of the graph adjacency matrix. Given the time series of data at different variables, the goal is to estimate these graph filters, hence the associated underlying adjacency matrix. Previously proposed algorithms have focused on a batch approach, assuming implicitly stationarity of the CGP. We propose…
Contributions to the analysis and design of all-inductive filters with dielectric resonators
2003
In this work, three modern full-wave methods will be employed for the accurate analysis and efficient design of a novel family of all-inductive filters loaded with dielectric resonators. These techniques are the bi-orthonormal-basis combined with the orthonormal-basis method, the hybrid mode-matching/spectral method, and, finally, the BI-RME (Boundary Integral-Resonant Mode Expansion) method. Then, two prototypes of band-pass filters have been designed in this work using a CAD tool developed in the research groups implicated in this manuscript. The procedure described in this paper only involves a limited number of actual physical parameters at each step so that it is computationally very e…
Accurate and precise lattice parameters by selected-area electron diffraction in the transmission electron microscope
2009
8 páginas, 6 figuras, 7 tablas.
Wavelet correlation filter for wide-angle seismic data
2002
A new filtering technique for single-fold wide-angle reflection/refraction seismic data is presented. The technique is based on the wavelet decomposition of a set of adjacent traces followed by coherence analysis. The filtering procedure consists of three steps. In the first, a wavelet decomposition of traces into different detail levels is performed. In the second, the coherence attributes for each level are evaluated by calculating cross-correlation functions of detail portions contained in a space–time moving window. Finally, the filtered traces are obtained as a weighted reconstruction of the trace details. Each weight is obtained from the coherence-attributes distribution estimated in …
An automatic filtering algorithm for SURF-based registration of remote sensing images
2017
International audience; The registration of remote sensing images has been often a necessary step for further analyses of images taken at different times, different viewing geometry or with different sensors. For this task there exists many approaches. This paper focuses on the feature-based category of image registration methods. Particularly, we propose an improvement of the SURF algorithm on the point matching step. Indeed, in order to achieve a correct registration, a good matching of feature point is required. However The presence of outliers lead to a fail in the registration. Therefore, in this paper, we introduce an efficient method devoted to the detection and removal of such outli…
Ethylbenzene removal under mesophilic conditions in a biofilter withMacadamia ternifolianutshells as a carrier material
2012
BACKGROUND Biofilters are suitable to treat industrial emissions polluted with volatile organic compounds (VOCs), responsible for photochemical smog and depletion of the ozone layer. This study analyzes the performance of a biofilter with Macadamia ternifolia nutshells as a carrier material treating air streams contaminated with ethylbenzene under mesophilic conditions with continuous feeding. RESULTS The biofilter was operated continuously for 5 months applying several inlet loads (IL), empty bed residence times (EBRT) and temperatures. At a temperature of 303 ± 1 K removal efficiencies (RE) higher than 90% were obtained for ILs lower than 85.6 g m−3 h−1 and 70.6 g m−3 h−1 at an EBRT of 15…
Biofiltration of toluene in the absence and the presence of ethyl acetate under continuous and intermittent loading
2008
BACKGROUND: Two peat biofilters were used for the removal of toluene from air for one year. One biofilter was fed with pure toluene and the other received 1:1 (by weight) ethyl acetate:toluene mixture. RESULTS: The biofilters were operated under continuous loading: the toluene inlet load (IL) at which 80% removal occurred was 116 g m−3 h−1 at 57 s gas residence time. Maximum elimination capacity of 360 g m−3 h−1 was obtained at an IL of 745 g m−3 h−1. The elimination of toluene was inhibited by the presence of ethyl acetate. Intermittent loading, with pollutants supplied for 16 h/day, 5 days/week, did not significantly affect the removal efficiency (RE). Biomass was fully activated in 2 h a…