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[en] Complete text of publication follows. Three-dimensional inversion of magnetotelluric data is becoming more widespread due to the availability of a small number of academic codes and access to some commercial codes. All of the existing ones lack the ability to consider the effects of local, near-surface inhomogeneities as galvanic distorters, and require fine meshing close to recording sites in order to mimic the observations. In addition, rotating field data into a uniform reference frame for modelling/inversion introduces higher noise levels on all channels. To combat both of these deficiencies, our inversion program, which uses a finite-element forward engine, differs from previous ones by solving for galvanic distortion parameters as well as Earth structure, and by using individual, local coordinate systems for each MT site instead of one global coordinate system. The code is called MCMT3DID (Marion and Colin's MT 3D Inversion code including Distortion). We will present the structure of the 3D finite-element code with the focus on some of the more interesting aspects (e.g., local coordinate system and distortion) including the different options and features (e.g., different approaches to include the distortion in the inversion process and to define the starting values for the distortion parameters) as well as the status of progress at the time of the conference. We will also show some preliminary results obtained from the first test data sets using the options in the code, which are fully implemented at that stage.
[en] The power of an optical signal detected upon nonstationary irradiation of a randomly irregular surface in the case when mutual shading of surface elements is an essential factor is investigated. An expression for an average (over an ensemble of irregular surfaces) power detected in location of a surface with a Gaussian distribution of heights and inclinations by a δ-pulse under conditions of strong shadings is derived. Shading is shown to produce a substantial distortion of the shape of the echo signal. 6 refs., 1 fig
[en] This invention refers to an electron microscopy process and a system to operate it. This process overcomes the drawbacks linked to previous systems in this sphere in that it enables the signal/noise ratio to be considerably increased in detecting either secondary electrons emitted by the samples or photons emitted by cathodoluminescence. This enables a finer analysis to be performed and avoids the degradation of the samples
[fr]La presente invention a pour objet un procede de microscopie electronique et un dispositif de mise en oeuvre. Ce procede pallie les inconvenients lies aux systemes de l'art anterieur en ce qu'il permet d'augmenter notablement le rapport signal/bruit dans la detection, soit des electrons secondaires emis par l'echantillon, soit des photons emis par cathodoluminescence, ce qui, d'une part, permet une analyse plus fine et, d'autre part evite la degradation de l'echantillon
[en] Massive neutrinos leave a unique signature in the large scale clustering of matter. We investigate the wavenumber dependence of the growth factor arising from neutrino masses and use a Fisher analysis to determine the aspects of a galaxy survey needed to measure this scale dependence.
[en] Complete analytical expressions for distortions caused by signal processing in analog AM modulators are developed. The salient features in these expressions are shown to be consistent with displays of actual spectra of AM signals. Finally suggestions are given on how the distortions may be practically minimized. (author). 6 refs, 3 figs
[en] A measure of the reliability of a transmission protocol is the likelihood that undetected errors in the transmitted data will occur. The author considers the effect of single bit errors on the error-detection mechanisms in the HDLC as defined in ISO Standard 3309. It is shown that the HDLC block synchronisation method is relatively vulnerable to the generation of undetected errors. Simple but effective methods of improvement within standard HDLC are to use fixed-length data bytes (e.g. of 8 bits), to give block length as part of the data, and to use a separate flag at the beginning and end of every block. (G.F.F.)
[en] We show that the output signals of conventional spectrum analysers contain distortions which basically originate from the signal processing performed inside the analysers' frequency convertors. Total elimination of these distortions through normal filtering techniques is difficult owing to the closeness of some of their frequencies to the corresponding frequencies of the required signals. Simple design adjustments that can minimize these distortions are suggested. (author). 7 refs, 2 figs
[en] Lorentzian signals are valuable information carriers on many science fields. Although well established procedures for nonlinear fitting exists, they tend to show slow performance when either a large number of bands or high resolution signals are involved. This work introduces a procedure that automatically makes an initial estimate of the band's parameters, which are subsequently improved by a routine called Simultaneous Height Adjust (SHA), designed for accounting neighbors' signal distortions, and a linear least square fitting procedure. As result, we obtain an easy to implement and fast procedure that, for the case of LIBS applications, never overestimates the peak's energy. - Highlights: • A fitting algorithm for signals composed by multiple Lorentzian shapes is proposed. • The execution time is linear when a high number of bands and/or points are employed. • Never overestimates peaks' energy. • Does not require user intervention
[en] The invention relates to cameras for detecting the ionizing radiation of radioactive isotopes, also known as 'scintillation', 'Anger' or 'nuclear' cameras, and especially to an electric circuit for correcting distortion due to photomultiplier tube spacing and arrangement, and to the distance between the tube array and the scintillation plate. The invention is described in relation to a radiation-sensitive camera; however, it should be noted that the invention has other applications in areas where distortion results from the non-linear response of a photomultiplier tube arrangement or other detection devices
[fr]Cette invention concerne les cameras de detection du rayonnement ionisant des isotopes radioactifs, parfois appelees cameras a scintillation d'Anger ou nucleaires, et plus particulierement, un circuit electrique de correction des distortions dues d'une part, a l'espacement des tubes photomultiplicateurs adjacents de l'arrangement de tubes et d'autre part, a la distance separant l'arrangement de tubes de la plaque de scintillation. On decrit l'invention en reference a une camera sensible au rayonnement ionisant, mais il faut noter que l'invention a d'autres applications dans d'autres domaines dans lesquels une distortion est due a une reponse non lineaire d'un arrangement de tubes photomultiplicateurs ou d'autres dispositifs de detection