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161.
The author presents a selection of cartograms designed to illustrate aspects of the demography of China. Topics covered include population growth, density, regional variations in fertility, and age distribution. A discussion of the advantages of using cartograms (maps drawn proportional to a given variable) as opposed to conventional, area-based maps, is included.  相似文献   
162.
M. J. Martres 《Solar physics》1989,119(2):357-384
This paper consists of two parts. We first discuss recent general results on the study of properties of flare homology, and their relevance to the physical interpretation of the flare phenomenon at large. We devote particular attention to the discovery of homologous flares which occur in rapid succession, within a few minutes of each other in many cases. We name these kind of flares rafales. These flares signal the existence of several episodes of energy release within the same magnetic configuration. We also show the existence of particular sites in the solar atmosphere which have peculiar characteristics in terms of solar rotation, and where recurrent flaring may take place over and over again in different solar rotations. This indicates that the disturbance causing the emergence of activity is deep seated, below the solar photosphere. Finally, in the second part, we discuss an extensive set of observations of two homologous flares of a rafale, stressing the dynamic aspects of the observations, particularly the presence of peaks in the vertical component of the velocity field. These results are shown to be in agreement with studies of filament activations and the surging arches which are observed before the flash phase of solar flares.  相似文献   
163.
The implications of the Gulf War are assessed for the countries in Asia that send labor migrants to the Middle East. "This paper seeks to examine the effects of...the loss of remittances (and related issues, including return migration), primarily in terms of the long-term implications of the War for the future of contract labour migration in the Asian region...."  相似文献   
164.
The shadowing effects of the molecular clouds in the nearby interstellar medium on the soft x-ray background has been investigated, using ROSAT WFC data in conjunction with previous rocket B and C band surveys. Shadowing over a 5° extent occurs only for a few percent of the sky, but the mixed model of the ISM is supported.Detailed modelling of the Draco shadowing region shows little evidence for a multi-temperature, hot ISM component.  相似文献   
165.
Population trends in the German and Austrian Alps between 1971 and 1981 are described. The effects of commune size, tourism, and altitude on population dynamics are considered.  相似文献   
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A non-steady, two-dimensional, compressible mathematical model of a fluid with constant viscosity and thermal conductivity is given in order to represent a thin atmospheric layer located at 60 km height, as a function of a known initial vertical distribution of temperature, chemical concentrations of minor components and assumed free boundary conditions.The purpose of this paper is to determine the influence of convective laminar processes in the vertical distribution of minor constituents in a thermal interface. Only three minor components are considered, atomic oxygen, molecular oxygen and ozone. Numerical solutions of the stated timedependent convection problem for different Rayleigh numbers show a marked influence of the established flow pattern upon the distribution of minor constituents. In all cases, an enhancement of mean concentration gradients in relatively small regions adjacent to the warmer and colder boundaries was observed.  相似文献   
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