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101.
The article investigates the state of stress and strain of the surface of an elastic cylindrical shell whose outer part is subjected to the effect of an incident acoustic wave. A qualitative and quantitative analysis of the state of strain of the surface is carried out and recommendations are given for optimizing the functional purpose of the shell and minimizing the arising stresses.Translated from Problemy Prochnosti, No. 4, pp. 43–47, April, 1991.  相似文献   
102.
The influence of the level of defectiveness of design and service origin (grooves and cracks) of a fastener and an impact specimen on the accuracy of determination of the allowable values of the ductile-to-brittle transition temperature is investigated. An evaluation of the allowable ductile-to-brittle transition temperatures making it possible to impose more soundly based requirements for effectiveness of the material in the stages of design, production, and service in relation to the production condition of the steel, the level of defectiveness of the fastener, and the specified operating life of the threaded joint is proposed.Translated from Problemy Prochnosti, No. 5, pp. 35–37, May, 1991.  相似文献   
103.
Long-term trends in alpine and prairie snow pack accumulation and melt are affecting streamflow within the Oldman River Basin in southern Alberta, Canada. Unchecked rural and urban development also has contributed to changes in water quality, including enhanced microbial populations and increased waterborne pathogen occurrence. In this study we look at changing environment within the Oldman River Basin and its impact on water quality and quantity. The cumulative effects include a decline in net water supplies, and declining quality resulting in increased risk of disease. Our data indicates that decreases in the rate of flow of water can result in sedimentation of bacterial contaminants within the water column. Water for ecosystems, urban consumption, recreation and distribution through irrigation is often drawn from waterholding facilities such as dams and weirs, and concern must be expressed over the potential for contaminate build-up and disproportionate potential of these structures to pose a risk to human and animal health. With disruption of natural flow rates for water resulting from environmental change such as global warming and/or human intervention, increased attention needs to be paid to use of best management practices to protect source water supplies.  相似文献   
104.
Filled fibrous sorbents modified with transition metal ferro- and ferricyanides capable to recover americium(III) and rare-earth metals(III) from nitric acid solutions were prepared. The most complete and rapid recovery is attained on complex-forming and cation-exchange sorbents (as filled fibrous materials) saturated with nickel ions. The sorbents are characterized by good kinetic properties and can be used for recovery of the above metals.  相似文献   
105.
The maximum-likelihood technique is applied to determine the coordinates of moving targets in a three-dimensional bistatic forward-scattering radar. The potential accuracy of the coordinates’ determination is estimated. Simulation results are presented.  相似文献   
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The results of a computational experiment with a neural-net model simulating the effect of the chemical composition on the plastic properties of ÉP-450 steel are presented. It is shown that computer-aided development of reactor steel with prescribed properties is, in principle, possible.  相似文献   
110.
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