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991.
Programming and Computer Software - In the biomedical domain, diagrammatical models have been extensively used to describe and understand the behaviour of biological organisms (biological agents)...  相似文献   
992.
The Journal of Supercomputing - In this paper, we propose a parallel source separation system designed to extract heart and lung sounds from single-channel mixtures. The proposed system is based on...  相似文献   
993.
The Journal of Supercomputing - General-purpose graphics processing units (GPGPUs) are extensively used in high-performance computing. However, it is well known that these devices’...  相似文献   
994.
Knowledge-based recognition and analysis of high dimensional data such as aerial images often has high computational complexity. For most applications time and computational resources such as memory are limited. Therefore approximately correct interpreters with any-time capability are proposed. In this contribution a special software architecture is published, which can handle the administration of complex knowledge-based recognition and analysis in a tractable manner.  相似文献   
995.
Microstructural changes during ageing of Cu-2.5 wt% Ti   总被引:2,自引:0,他引:2  
Microstructural changes in Cu-2.5wt % Ti during ageing at 573 and 773 K have been studied by transmission electron microscopy. Ageing times ranged from 60 sec to 200 h. Ordering of the precipitates was observed after very short ageing treatments at 773 K, and coarsening according tot 1/3 was also observed from very early times. The particles were observed to become increasingly aligned into rod-like groups along 10 0 as ageing progressed. These results permit a new interpretation of the strengthening mechanisms in this alloy.  相似文献   
996.
Stress-sensitivity mapping for surface acoustic waves on quartz   总被引:1,自引:0,他引:1  
A model is presented, relating the velocity shifts of surface acoustic waves (SAW) to the six tensor components of quasistatic stresses. Stress sensitivity is then defined through six independent coefficients, whatever the origin of the stress (direct external forces, thermoelastic stresses) might be. These coefficients, depending on crystal anisotropy, are computed for different cut angles and propagation directions of quartz crystal, and represented as a contour-line mapping. The determination of SAW quartz cuts compensated for both planar isotropic stresses and first-order temperature effects make it possible to define a family of quartz cuts with potentially low stress and temperature sensitivities for oscillator applications.  相似文献   
997.
998.
We have established general quantitative relationships linking the magnitude of the induction period in isothermal and nonisothermal regimes of oligomer hardening for the case in which the nonisothermicity is determined by the kinetics of heat generation in the chemical reaction.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 56, No. 4, pp. 591–595, April, 1989.  相似文献   
999.
A comparison between simulation- and measurement-based characterization is provided for the design of one-dimensional, nonadaptive, inverse filters for ultrasonic applications. Both prefiltering and postfiltering are considered by means of two different filtering strategies performed in the time and frequency domains. The results clearly indicate that theoretical methods can be used successfully, provided that the physical limitations of the simulation process are fully appreciated. In some instances, the simulation-based approach is shown to provide superior results, and the reasons for this are explained.  相似文献   
1000.
The integrated backscatter calculation over the full, two-dimensional echocardiographic sector is implemented to produce images from closed-chest dogs. This new real-time integrated backscatter measurement system allows a continuous determination of integrated backscatter from all myocardial regions in the ultrasonic view. By replacing the conventional video processor in a commercial two-dimensional echocardiographic imager with this new real-time backscatter measurement system, it is possible to produce real-time two-dimensional images based on integrated backscatter.  相似文献   
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