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71.
The conventional model of the relationship between welfare incentives and poverty rates holds that welfare payments produce an income-enhancement effect that removes families from poverty until some threshold. Beyond this point increased payments engender a work-disincentive effect resulting in increased rates of poverty. We challenge the model's assumption that poverty levels are a simple and spatially invariant response to welfare incentives, contending instead that local employment conditions may substantially alter the relation. Our reformulation of the conventional modeling approach is based on the expansion method. Specifically, we extend the model to include the effects of local labor-market conditions on the response of poverty levels to welfare incentives. In contesting the invariance assumption, the expansion method allows us to determine where and in what contexts welfare is “work discouraging.” The empirical analysis, which is undertaken at the county level, indicates that welfare payments vary in their influence on poverty rates across different employment contexts. A national map portraying this parameter instability demonstrates that female-family poverty rates are most responsive to welfare assistance in the rural South and least responsive in the metropolitan Northeast. Finally, we examine two sharply contrasting locales to illustrate how poverty is governed by specific employment and welfare characteristics. 相似文献
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74.
THOMAS F. MclLWRAITH 《The Canadian geographer》1995,39(4):323-335
This paper demonstrates that the morphology of ordinary rural roads tells much about regional development. It uses southern Ontario as a case study, but the principles may be applied widely. It is a plea for recognition of a deep heritage in unspectacular things: ditches, fence-lines, culverts, jogs in the survey, and more. This paper also encourages local and regional planners to conserve signs of change in the roadscape and to celebrate them. Roadside evolution is worth publicizing, and unnecessary destruction of elements that enhance the story must be discouraged.
Cet essai démontre que la morphologie des routes rurales ordinaires en dit beaucoup au sujet du développement regional. On peut employer cet exemple de /'Ontario du sud mais les principes peuvent s'appliquer d'une manière plus large. Dans ce manuscrit on doit reconnaître /'heritage profond des elements communs: des caniveaux, des clotures, des aqueducs, des irrégularity de I'arpentage, etc. Cet essai encourage aussi les planificateurs i conserver ces signes du paysage routier et à les mettre en Évidence. On doit les faire connaître au public, et décourager leur déstruction. 相似文献
Cet essai démontre que la morphologie des routes rurales ordinaires en dit beaucoup au sujet du développement regional. On peut employer cet exemple de /'Ontario du sud mais les principes peuvent s'appliquer d'une manière plus large. Dans ce manuscrit on doit reconnaître /'heritage profond des elements communs: des caniveaux, des clotures, des aqueducs, des irrégularity de I'arpentage, etc. Cet essai encourage aussi les planificateurs i conserver ces signes du paysage routier et à les mettre en Évidence. On doit les faire connaître au public, et décourager leur déstruction. 相似文献
75.
76.
Pedro Pérez Herrero 《Colonial Latin American Review》1995,4(1):217-232
Tráfico de Indias y política oceánica. By Fernando Bordejé Y Morencos. Madrid: MAPFRE, 1992. Pp. 341.
Relaciones económicas entre España y América hasta la independencia. By John R. Fisher. Madrid: MAPFRE, 1992. Pp. 280.
Las comunicaciones en América. By Secundino‐José Gutiérrez Alvarez. Madrid: MAPFRE, 1993. Pp. 424.
Piratas, bucaneros, filibusteros y corsarios en América. Perros, mendigos y otros malditos del mar. By Manuel Lucena Salmoral. Madrid: MAPFRE, 1992. Pp. 306.
El dinero americano y la política del imperio. By María Emelina Martín Acosta. Madrid: MAPFRE, 1992. Pp. 333.
Cargadores a Indias. By Julian B. Ruiz Rivera and Manuela Cristina García Bernal. Madrid: Mapfre, 1992. Pp. 395. 相似文献
77.
Morphological Impacts and Implications of a Trial Release on the Wingecarribee River,New South Wales
A trial, monitored release on the Wingecarribee River over 27 days had a peak discharge below the Wingecarribee Dam of 1090 ML/d, which had a flow duration of 0.95 per cent. Morphological impacts on 29 km of channel below the dam included bank erosion, concentrated neck overflow, bed degradation and channel widening at recent cutoffs, sedimentation in weir pools and overbank flow, particularly at discharges greater than 800 ML/d. Prolonged operational releases at bankfull discharge (400–800 ML/d) will have the greatest morphologic impacts and should be avoided. Pulses which dissipate stream power over a broad, well-vegetated floodplain should be incorporated in the operational release policy, provided such pulses are phased to facilitate channel and vegetation recovery. 相似文献
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79.
C. F. W. Higham 《International Journal of Historical Archaeology》1998,2(3):235-260
The Early Historic Period in the Mun Valley occupies a critical three centuries, from A.D. 500 to A.D. 800, a period often known as that of Zhenla, a name derived from early Chinese accounts. This article first describes early findings of fieldwork designed to illuminate the prehistory of the upper Mun Valley, a period which covers approximately two millennia, with initial settlement now dated between 1500 and 1000 B.C. It then considers the nature of the transition to the complex polities of Zhenla. This involves a combination of archaeological and documentary evidence. Sources for the latter are rare for the Mun Valley, but by broadening the area considered, it is possible to integrate archaeological and historical sources in order to portray the intensifying social changes which characterize the Early Historic Period. It is suggested that most of the Mun Valley was occupied by Khmer speakers during the Iron Age, people responsible for the transition to increasingly centralized polities of the Early Historic Period. In the upper reaches of the Mun catchment, and in the Chi Valley to the north, the late prehistoric inhabitants spoke Mon. They had close affinities with the Dvaravati polities of Central Thailand. If confirmed, this hypothesis would indicate a series of local trends towards increasing social complexity which we can recognize in the early epigraphic record. 相似文献
80.
Bénédicte Zimmermann 《European Review of History》1998,5(1):9-23
Concepts of unemployment or of the labour market are not abstract, but develop from each society's own particular logic. Taking the examples of Germany and France at the end of the nineteenth century, it is possible to see how these concepts were constructed in specific national contexts, and how they were then used in practice. This analysis leads us to rethink current ideas about work and unemployment, and to ask what their future will be in a united Europe. 相似文献