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991.
It has been demonstrated previously (see E.L. Ritman and A.A. Bove, in State of the Art in Quantitative Coronary Arteriography, p.67-78, 1986) that coronary artery anatomy can be visualized using high-speed, volume-scanning X-ray CT (computed tomography). In the current study it is demonstrated that local image reconstruction (i.e. the reconstruction kernel is ~2(+) mm long), as distinct from more conventional global image reconstruction (i.e. 200(+) mm kernel length), has the advantage of reducing the need for operator interactive image processing. In addition, the local reconstruction algorithm eliminates the need for recording the X-ray projection data over the full transaxial extent of the thorax because it requires only the X-ray attenuation data over the region of the heart. This latter aspect reduces the dynamic range requirements for the sensors and could reduce total X-ray exposure. 相似文献
992.
A. S. Zalesov S. E. Lisichkin 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1990,24(3):221-226
1. | The suggestions on calculating the strength of concrete joints with transverse reinforcements were made on the basis of using the method of secondary stress fields and permit more complete consideration of the effect of the characteristics of the stress state on the strength of massive members. |
2. | Unlike the preceding developments, the present suggestions make it possible to evaluate the reinforcement and concrete strength of the structural member being designed with pin resistance of the transverse bar reinforcement to the effect of the initial and secondary shear stresses in the longitudinal joint. |
3. | The installation of an additional amount of transverse reinforcement precludes the probability of separation of the massive member along the longitudinal block joint and provides reliable and safe operation of the structure. |
993.
Method of calculating the technological parameters when designing hydraulic-fill dams of silty soils
E. L. Vvedenskii 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1990,24(6):354-362
1. | Investigations showed that when constructing dams of fine-grained silty soils by hydraulic filling, it is expedient to use the technology of layerwise placement of soil with consolidation of each layer. |
2. | Dependences are given for calculating the thickness of the layers and period of consolidation of the soil on the basis of investigations of the dynamics of the hydrophysical properties of these soils in relation to technological factors. |
3. | Dependences are also proposed for predicting the density of the hydraulic-filled soil during construction, as well as the distribution of soil in the profile of the structure. |
4. | A method is proposed for calculating the technological parameters, in particular, the rate of construction of hydraulic-fill structures, calculating the size and number of the hydraulic-fill plots referred to one dredge, and prediction of the seepage discharge into the foundation of the dams during their hydraulic filling. |
5. | The proposed calculation methods make possible a more substantiated approach to the design of hydraulic-fill structures of fine-grained silty soils and technology of their construction. |
994.
Translated from Khimiya i Tekhnologiya Topliv i Masel, No. 2, pp. 31–32, February, 1990. 相似文献
995.
M. E. Kassner 《Journal of Materials Science》1990,25(4):1997-2003
Previous elevated-temperature experiments on 304 stainless steel clearly show that the density of dislocations within the subgrain interior influences the flow stress at a given strain rate and temperature. A re-evaluation shows that the hardening is consistent with the Taylor relation if a linear superposition of solute hardening (
0, or the stress necessary to cause dislocation motion in the absence of a dislocation substructure) and dislocation (Gb
1/2) hardening is assumed. The same Taylor relation is applicable to steady-state structures of aluminium if the yield stress of annealed aluminium is assumed equal to
0. New tests on aluminium deforming under constant-strain-rate creep conditions show a monotonic increase in the dislocation density with strain. This and the constant-stress creep trends are shown to be possibly consistent with Taylor hardening. 相似文献
996.
Burdonov I. B. Vinarskii E. M. Yevtushenko N. V. Kossatchev A. S. 《Programming and Computer Software》2021,47(7):505-514
Programming and Computer Software - This paper investigates the implementation of virtual networks on the SDN data plane modeled by a graph of physical connections between network nodes. A virtual... 相似文献
997.
Programming and Computer Software - We define a problem of certifying computation integrity performed by some remote party we do not necessarily trust. We present a multi-party interactive protocol... 相似文献
998.
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
999.
Muñoz-Montoro A. J. Suarez-Dou D. Cortina R. Canadas-Quesada F. J. Combarro E. F. 《The Journal of supercomputing》2021,77(8):8135-8150
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
1000.
Condia Josie E. Rodriguez Narducci Pierpaolo Sonza Reorda Matteo Sterpone Luca 《The Journal of supercomputing》2021,77(10):11625-11642
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