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141.
142.
广东人口迁移机制、特征与走向 总被引:3,自引:0,他引:3
80年代以来广东省活跃的人口迁移,其主要动因是改革开放中广东省与国内其它地区以及省内珠江三角洲与其它地区之间经济的不平衡发展。广东省人口迁移有其显著特征,而区域经济发展水平的差异、产业结构特征及劳动力供求关系的发展等又影响着未来的人口迁移走向。 相似文献
143.
David H. Kaplan 《The Professional geographer》1995,47(2):115-125
This study utilizes linguistically disaggregated region-to-region migration data between 1981 and 1986 to demonstrate that French and English speaking Canadians react differently to place attributes. A series of log transformed linear regression models suggest that the two populations differ very little in their response to traditional labor market variables but that they diverge dramatically in their response to the linguistic composition of each region. Each group prefers regions with a greater percentage of their own co-linguists, but Francophones are less sensitive than Anglophones to linguistic composition. 相似文献
144.
As a result of restrictive time-space bounds in viewing migration, surprisingly little is known about the tempos and rhythms of geographical mobility in America. We discuss limitations of the conventional definition of migration and develop a life course framework of multiple residence and cyclical migration. Results of an Arizona-based case study reveal that multiple residence is common and more diverse than the annual influx of elderly snowbirds. Coming to grips with multiple residence and recurrent mobility in the United States represents a fundamental challenge in population and migration studies. 相似文献
145.
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147.
This paper analyzes the migration of Puerto Rican-born women from the United States to Puerto Rico using longitudinal data. We hypothesize that sojourn length in the United States is a function of both structural (macro-level economic and cultural factors) and behavioral (micro-level life-cycle experiences and personal attributes) variables. We test these hypotheses by estimating a proportional hazards model. The parameter estimates of this model indicate that sojourn length in the United States, and thus the decision to return to Puerto Rico, is a function of wage trends and community characteristics on the mainland plus a number of individual attributes that include education, marriage, and childbirth. 相似文献
148.
James Pooler 《The Professional geographer》1993,45(3):297-305
This paper identifies a concept of structural spatial interaction. Although it is defined differently from its counterpart of structural unemployment in economics, it attempts to define a similar idea. In economics, the focus is on equilibrium in the supply and demand of labor. In this paper structural interaction is that which minimizes aggregate distance travelled, subject to constraints on origins and destinations. The structural interaction model produces an equilibrium, therefore, in the supply and demand of movers, while identifying a spatially efficient trip distribution. It is portrayed as a type of relaxed interaction model and is illustrated using an example of structural migration with Canadian interprovincial migration data. 相似文献
149.
A ground geomagnetic survey conducted in peninsular India has demarkated the dip equator for the epoch 1991.0. A well-defined
southward migration in the last two decades is evident. The secular trend in the vertical component and the direction of the
migration in the India zone are shown to be consistent. The migratory movement of the dip equator in different longitude sectors
is compared to highlight the complex nature of the secular trends. 相似文献
150.
王开怡 《大地构造与成矿学》1991,15(2):138-143
中国东部地壳地洼阶段的热塑性变形应力场有利于锡成矿。构造应力场对锡成矿的控制作用,表现为对成矿域的矿液运移势和能量场的控制。推导获得矿液运移势的计算公式:Vi=-(a·K_0/u)·[exp(σ_1-σ_2)]·(σ_1+σ_2),表明地壳构造应力场对成矿域矿液的运移和成矿部位的选择提供了有利的动力学条件。 相似文献