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121.
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ADA W. PRINGLE 《Geographical Research》1996,34(1):58-80
The history of dredging is examined for Cleveland Bay, 1883–1988, as the port of Townsville developed. Between 1883 and 1964 only intermittent data exist on localities, depths and quantities dredged but later much more detailed records are available for analysis. Geomorphological problems emerged and are considered with particular reference to material forming the seabed, the sediment yield from the coastal catchments and its seasonally and annually irregular delivery to the coast by the rivers, and sediment movement within the bay in response to wind, wave and tidal processes. Analysis of aerial photographs, 1941–1988, has enabled some dredging effects to be studied, especially relating to localised land reclamation and more widespread probable effects on seagrass beds and mangroves. 相似文献
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The repeated failure to design and appropriately target policies and interventions which address the needs of rural peoples in Africa suggests that something may be wrong with our understanding of the way that these peoples live their lives. Perspectives which focus on intra-household processes, and on gender issues in particular, represent useful advances in the way that the social and economic lives of Africa's rural peoples are conceptualized. However, this article questions the value of adopting development planning, policy and project approaches based on the rigid identification of `gender roles'. By reference to field research undertaken in northern Ghana, the paper aims to demonstrate that other social constructs, such as marital status and seniority, may be as important as gender in determining the roles and status of individuals in African rural societies. The article concludes by highlighting a number of practical implications of this finding in terms of the structuring of development-oriented research and the targeting of policy and interventions. 相似文献
125.
Some 630 Roman silver coins excavated at Augusta Raurica (Switzerland) have been analysed by non-destructive X-ray fluorescence and X-ray diffraction. Furthermore, the density and the weight have been determined. The measured average density of plated and massive depletion-silvered coins is lower than the density calculated from the chemical composition, whereas massive coins display equal values for both of the densities. Based on experimental X-ray investigations of modern silver (tempering, acid treatment, production of corrosion layers), the nature of corrosion products on silver, their impact on surface analysis, and aspects of wearing-off by circulation are briefly discussed. 相似文献
126.
SPATIAL DEPENDENCY OF SEGREGATION INDICES 总被引:3,自引:0,他引:3
David W.S. Wong 《The Canadian geographer》1997,41(2):128-136
A few researchers have mentioned the scale sensitivity of segregation index, D. In this paper, I discuss analytically and empirically why using large enumeration areal units usually results in low segregation measures, and using small areal units produces relatively high segregation measures. The discussion is also applicable to the multi-group variant of D. A major finding is that if people of the same ethnic groups are positively spatially auto-correlated, increasing the size of areal units of analysis may not lower D initially, because only people of the same group are added. But enlarging the areal units subsequently may include population of other ethnic groups, and therefore could lower D. However, if the boundaries of the larger enumeration units are drawn to include only population of the same group, then D will not change significantly. Both the spatial autocorrelation of ethnic group population and zonal pattern are critical factors in determining the scale sensitivity of D. 相似文献
127.
Jean-Marc Drouin Patrick Gautier Dalché Fabien Chareix Charles Lenay Monique Cottret Bernard Vandewalle François Laplanche Françoise Waquet Agnès Spiquel Ariane Poulantzas Olivier Martin Sophie Roux Ilana Löwy Françoise Waquet Isabelle Brian Michel Cassan Jean-Marc Rohrbasser Jean-Michel Vienne Marc Renneville Bernard Lahire Mikhaäl Xifaras Bertrand Binoche Stéphane Haber Jean-François Pradeau Noël Bonneuil Marie Jaisson 《Revue de synthèse / Centre international de synthèse》1997,118(4):551-613
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Participants in a statewide family preservation program were classified on the basis of income level and enrollment in public assistance. These variables, along with other economic, parent, and child risk factors, were used to predict the probability of out-of-home placements at the close of this intervention program. Results revealed that neither low income nor receiving public assistance was predictive of having a child removed from the home. Higher levels of child-centered risk and parent-centered risk were the only consistent predictors of placement outcomes. Additional analyses revealed that family characteristics (e.g., history of psychiatric care, prior child placements, and involvement with the legal system) also were typical of families experiencing out-of-home placements. This study challenges the stereotype of low-income or welfare families being at greater risk of having a child removed from their home. Findings are discussed in the context of recent welfare reform initiatives and implications for future family policy research. 相似文献