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941.
942.
The specific features of the solver system for the Ek(R2) problem of locating geometrical objects are presented. A strategy for the construction of the system as a mapping of the set of problems on the set of solution methods is proposed.Translated from Kibernetika i Sistemnyi Analiz, No. 5, pp. 31–40, September–October, 1991.  相似文献   
943.
944.
We describe planar buried heterostructure lasers which have low capacitance (lpF), large bandwidth (19GHz), high power (>20mW/facet) and high temperature operation (100°C). These lasers are very suitable for long-distance, highspeed digital and analogue signal transmission.  相似文献   
945.
The device developed allows one to measure the dielectric characteristics of solid substances and their melts at frequencies of 20–20000 Hz and in a wide temperature range of 20–250°C. The measured temperature dependencies of the dielectric permittivities of several molecular and liquid crystals (stilbene, diphenyl, naphthalene, cholesterylpelargonate, and 8OCB) are presented.  相似文献   
946.
Although RALOC4 code is validated against many experiments with regard to Western Nuclear Power Plants (NPPs) the code validation problem for the Accident Localization System (ALS) of Ignalina NPP modeling is of special importance because the condensing pools at NPP with RBMK-1500 differ from the pressure suppression systems installed in NPPs with German BWR. The response of Ignalina NPP ALS to the unintentional opening of single Main Safety Valve, which occurred in 1998, is analyzed by employing code RALOC4. The results of post-event calculations compared with the measured data available after the event. The performed analysis showed that RALOC4 code could be applied for the simulation of Ignalina NPP ALS. Nevertheless, the spray modeling in RALOC4 should be improved allowing the simulation of sprays in NON_EQUILIBRIUM zone model and to consider the diameter of water droplet diameter and height of droplet fall.  相似文献   
947.
Smoke produced by arcing of two aluminium rods in air is found to be composed of gamma-alumina spheres with a size range of 6 to 500 nm. While most particles are solid, single crystals with many exhibiting complicated stacking faulting and twinning, some are hollow. In appropriately clean conditions the surface is observed to be complicated, with the steps in some areas being directly related to the alumina lattice. Heating in air at 1150° C for 48 h transforms the sphere morphology of gamma to plate-and-block type alpha-alumina. Direct evidence of surface diffusion during this transformation is observed.  相似文献   
948.
949.
A framework for incorporating uncertainty in risk management is developed and applied to two aspects of decision making: meeting standards or safety goals, and cost-benefit criteria. The framework is applied to several case studies including toxic chemicals in water, failure of civil engineering structures and nuclear power plants. The framework proposes that decisions be based on a level of confidence, in addition to comparing best estimate or point values with standards and goals.  相似文献   
950.
In this paper we deal with the coupled thermoelastic problem of an elastic medium (x1, x2 ? [?∞, + ∞], x3finite). The analysis is based on the decoupled field equations and the integral transforms. The dynamic behaviour of an elastic half-space due to a thermal shock on the boundary is also discussed.  相似文献   
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