[en] Distributed Arithmetic is more efficient than multipliers for implementing finite impulse response (FIR) digital filters on an FPGA. The functional simulation, timing simulation and implementation of the FIR digital filter by using ISE, verify the results on the board and at last complete the spectrum analysis of the output signals by using Matlab. The digital filter is designed for the baseline measurement in a noisy environment. (authors)

[en] A digital radiographic picture processing system has been developed at the EDF Research and Development Laboratory to be supplied to EDF radiography experts. We describe it in pointing out the difficulties of radiograph digitization but also the numerous processing possibilities. The final goal of the Laboratory work is to extract the information from industrial radiographs by digital means. Our study is divided into three parts: digitization by a microdensitometer; display, processing and quantization of flaws; and, digital storing. 5 refs

[en] Recently iterative procedures have been proposed for track and vertex fitting in counter experiments. We show that the proper theoretical framework for these procedures is the theory of linear filtering, in particular the Kalman filter. Using results from filtering theory we confirm and extend the previous results. We also discuss the detection of outliers and of secondary vertices. (orig.)

[en] In order to perform automatically the thresholding of the amplitude image obtained by phase analysis, a filter based on the probability density of the amplitude is proposed. It generates the image of the significant amplitude by setting to zero the amplitude if its square is lower than 4α₀ log(1/α)/N where α₀ is the mean of the signal, α the risk of error and N the number of frames. The power of the test is discussed and the modification of the filter for pre-processed data is provided. (author)

[en] The three-point method is a technique that uses three displacement sensors to separate the out of roundness of a reference sphere or cylinder as well as the spindle run-out. This method has high potential for ultra-high-precision measurements. However, applications of the three-point method have been impeded because the setting angles of the sensors have not been clearly established. In this paper, the effects of uncorrelated noise in sensor outputs on the calculation results of the roundness are analyzed by applying the process of the three-point method as a digital filter. Then, the optimum sensor angles, which minimize the effects of the noise, are computed where there is uncorrelated white or pink noise in sensor outputs. In addition, the effects of correlated noise in sensor outputs are analyzed

[en] With the help of digital processing of radiographic images from reactor-components it is possible to increase the security and objectiveness of the evaluation. Several examples of image processing procedures (contrast enhancement, density profiles, shading correction, digital filtering, superposition of images etc.) show the advantages for the visualization and evaluation of radiographs

[en] A frequency-domain criterion for the elimination of limit cycles in a class of digital filters utilizing single saturation nonlinearity is presented. The criterion is derived by exploiting the structural properties of the system under consideration in a greater detail. A novel feature of the criterion is that it takes the form of a matrix inequality, despite the fact that there is single nonlinearity in the system. An example showing the effectiveness of the criterion is given

[en] Published in summary form only

No abstract available

[en] We present a new approach for the design of optimum filters with good low frequency rejection suitable for high resolution nuclear spectrometry. The method, based on digital filtering techniques, permits to well approximate the theoretical signal-to-noise ratio limit while keeping a good rejection to slow disturbing waveforms. The proposed filter weight function uses the open-quote radiation-free close-quote time intervals closely spaced around the signal pulse for optimally estimating the baseline level and subtracts the obtained value from the pulse height estimate. We show that the resolution loss due to the open-quote optimum baseline restoration close-quote is of the order of a few percent even in case of high repetition rates, with a considerable improvement compared to an algorithm of simple average of the baseline samples. Because the occurrence of the radiation free time intervals is generally subject to a Poissonian statistic, the filter must be adaptive, which implies that the overall weight function is stochastic. The low-frequency rejection for this stochastic filter has been determined as a statistic property, resulting from the average of the used filter frequency responses