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991.
V. V. Skurat N. M. Shiryaeva N. K. Myshkina A. A. Gvozdev G. Z. Serebryanyi N. B. Golikova 《Journal of Engineering Physics and Thermophysics》2002,75(5):1200-1206
Unsatisfactory conditions of storage of decontamination waste (DW) in the storages formed in the territory of Belarus after the Chernobyl accident require the evaluation of the level of protection of the environment and population. The potential hazard of the decontamination waste burial grounds (DWBGs) has been evaluated based on the use of a generalized multichamber model that was verified by comparing the calculation results and the results obtained by the American (GW SCREEN) model. The characteristics of the 24 largest and most hazardous DWBGs are given and the evaluations of their safety are presented. The zones of influence of these storages, whose size varies from 100 to 330 m, have been determined. The reliability of the prediction evaluation of a possible hazardous radioactive contamination of water near the storages has been verified using the Dudichi DWBG as an example. 相似文献
992.
V. G. Gorobets 《Journal of Engineering Physics and Thermophysics》2002,75(5):1130-1138
A mathematical model of heat transfer has been developed and numerical calculations for a vertical surface with discrete fins arranged in staggered order have been carried out. The model accounts for the influence of the heat-conduction properties of the finning material and of the fin size on the conditions of heat transfer. A comparison of the results obtained with the existing numerical and experimental data has been made. This comparison shows that the discretization intensifies the heat-transfer process by 50–70%, and neglect of the heat-conduction properties of the fins leads to overstated values of the removed heat fluxes. 相似文献
993.
Two parameters affecting useful solar absorption are orientation and thermal mass. Solar energy absorption in buildings depends on these parameters in a complex manner particularly when considering large glazing ratios and large direct components of insolation. Therefore, where parameters of different zones in a multi-zone building vary, useful solar absorption will also vary. For higher northern latitudes, compared with south orientation, useful solar absorption differs by about 2%, 4% and 6% between large and small time constants for east, west and north orientations, respectively. The smallest and largest differences are for east and north orientations, respectively. Fenestration design should be a consequence of orientation and overshading, seeking to balance daylight, solar gains and heat losses. 相似文献
994.
995.
The utility of heart-rate variability (HRV) to index important aspects of neural control of the heart has made it one of the most valuable tools for researchers interested in health and behavior. However, most of the literature and extant data on the central origins of HRV have been derived from animal models. As yet little is known about the central nervous system (CNS) origins and concomitants in humans. In the following we will briefly detail a set of neural structures that have been associated with important CNS functions including cardiac regulation and emotional regulation. We will briefly summarize recent data using pharmacological, neuroimaging, and psychophysiological techniques that have examined CNS concomitants of HRV especially during emotion. Based on these and other data will we report the results of a computational model that examined the interactions of several neural structures and their effect on emotion-related HRV. 相似文献
996.
997.
近年来,地震地层学得到了大力的推广,各油田各探区纷纷利用这个工具对地震剖面进行重新解释,取得了一批初步成果;石油地质和石油物探界已几乎很少有人不知道有地震地层学了,这是一个十分可喜的现象。但我们也应该看到在推广过程中出现的一些问题,不要让这些问题阻碍了地震地层学在中国的发展,更不要让它们掩盖、冲淡了建立和发展岩性地震学这个对物探来说是更根本的任务。 相似文献
998.
The electric field (EF) model was first developed on a "breadboard" using physical electric components (e.g., resistors, capacitors, batteries) and was then modeled mathematically by a series of differential equations and matrix equations and simulated on a large computer (CDC-6400). The results obtained by the two methods agreed very closely. However, these two methods of analysis are quite cumbersome. Therefore, in order to simplify the EF simulation, we wanted to model it on the PSpice program. In this article we discuss how we succeeded in demonstrating transmission of excitation from cell to cell in cardiac muscle and smooth muscle based on EF transmission at the cell junctions. 相似文献
999.
1000.
The adobe house developed in the hot arid climate of the American Southwest has the virtue of being cool in the day and warm in the night. The adobe wall acts as a filter giving nearly a 12-hr phase lag in the outside temperature oscillation. However, on reaching the inside, the oscillation suffers a strong attenuation in amplitude. In a previous paper it was shown that if the resistivity of the wall could be varied in a certain way from outside to inside, thenthe attenuation would be considerably reduced. In this paper a formula is given for the minimum possible attenuation under given design restrictions. Then it is shown how to make an optimum wall by suitably proportioning two or three layers of different materials. Numerical illustrations are given. 相似文献