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991.
A circuit that uses the parallel connection of a Schmitt-trigger-type multivibrator and a voltage-controlled current source is proposed. The circuit was developed for use with integrated silicon sensors. The operation of the circuit is described  相似文献   
992.
993.
994.
Summary The crystallization and melting behaviour of poly(butylene terephthalate) has been studied in the pure state and in its blends with a polyarylate of bisphenol A and isophthalic/terephthalic acids. Differential scanning calorimetry has been used as experimental technique and the effects of different thermal treatments have been analyzed. Results show the hindrance for the crystallization of poly(butylene terephthalate) imposed by the presence of polyarylate, as well as the existence of multiple melting after isothermal crystallization. Explanations are given for the observed behaviours.  相似文献   
995.
996.
This paper reviews the activity in adhesion science of the Department of Applied Chemistry and Chemical Engineering (CNRS, URA 417) of the University of Lyon, France. This work essentially concerns treatments and modifications of surfaces by various chemical, electrochemical and physical techniques-electropolymerization, plasma polymerization, sol-gel processes, phosphatation, etc. Examples of the characterization of these surfaces and that of bonded joints are shown. Emphasis is placed on the possibilities offered by the techniques developed in the laboratory (low-energy electron-induced X-ray spectrometry and the three-point flexure test).  相似文献   
997.
998.
On LP-MUSIC     
Studies the consistency properties of a method recently proposed for temporal or spatial frequency estimation from noisy data. The method in question is a MUSIC technique that makes use of a linear prediction algorithm to determine the signal subspace. It is shown that the signal subspace determined by the subject linear prediction-MUSIC (LP-MUSIC) algorithm can collapse in certain scenarios and. Hence, that the LP-MUSIC frequency estimates are not always consistent. The difficulties LP-MUSIC may encounter in some cases are illustrated by means of numerical examples  相似文献   
999.
The phase diagram of the TlInSe2–TlPrSe2 system was mapped out using differential thermal analysis and x-ray diffraction data. The system was found to contain a partial solid-solution series (0–10 mol % TlPrSe2) and a quaternary compound of composition Tl2InPrSe4. The electrical conductivity, Hall coefficient, and thermoelectric power of TlPrSe2 and Tl2InPrSe4 were measured in the temperature range 300–1100 K. The charge carriers in these compounds were shown to be scattered mainly by longitudinal acoustic phonons.  相似文献   
1000.
The effect of a secondary path signal on the detectability of the symbol rate spectral line of a binary phase-shift keyed (BPSK) signal by a delay and multiply receiver is investigated. The measure of detectability used is the rate line signal-to-noise ratio. The parameters that define the secondary path signal are initially modeled as deterministic quantities; the phase of the secondary path signal is then taken to be a random variable independent and uniform on (0, 2π). It is found that, with deterministic path parameters, the presence of a secondary path can seriously affect the detectability of BPSK rate lines. When the phase is taken to be uniform on (0, 2π) over the receiver observation time, then the delay and multiply receiver performs as if no multipath is present. In this case, a noncoherent power addition of the primary and secondary path signals occurs  相似文献   
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