994 resultados para historical images


Relevância:

30.00% 30.00%

Publicador:

Resumo:

This thesis addresses how Alexis de Tocqueville’s political thought is related to American Exceptionalism. First, I illustrate the multiple meanings of the concept of American Exceptionalism and in what sense it is indebted to Tocqueville. Second, I articulate how the historical background and personal qualities of Tocqueville contribute to the success of his masterpiece Democracy in America. In the main part, by analyzing Tocqueville’s Democracy in America and other writings on America, I argue that he indeed reveals America as exceptional and increasingly recognizes this idea through a process of intellectual development. An elaboration on Tocqueville’s theoretical contribution to the discussion of American Exceptionalism can reveal the different images of modern democracy as he suggests and how they would influence the prospect of human freedom.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Historical archaeology, in its narrow temporal sense -as an archaeology of the emergence and subsequent evolution of the Modern world- is steadily taking pace in Spanish academia. This paper aims at provoking a more robust debate through understanding how Spanish historical archaeology is placed in the international scene and some of its more relevant particularities. In so doing, the paper also stresses the strong links that have united historical and prehistorical archaeology since its inception, both in relation to the ontological, epistemological and methodological definition of the first as to the influence of socio-political issues in the latter. Such reflection is partly a situated reflection from prehistory as one of the paper’s authors has been a prehistorian for most of her professional life.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Current procedures for flood risk estimation assume flood distributions are stationary over time, meaning annual maximum flood (AMF) series are not affected by climatic variation, land use/land cover (LULC) change, or management practices. Thus, changes in LULC and climate are generally not accounted for in policy and design related to flood risk/control, and historical flood events are deemed representative of future flood risk. These assumptions need to be re-evaluated, however, as climate change and anthropogenic activities have been observed to have large impacts on flood risk in many areas. In particular, understanding the effects of LULC change is essential to the study and understanding of global environmental change and the consequent hydrologic responses. The research presented herein provides possible causation for observed nonstationarity in AMF series with respect to changes in LULC, as well as a means to assess the degree to which future LULC change will impact flood risk. Four watersheds in the Midwest, Northeastern, and Central United States were studied to determine flood risk associated with historical and future projected LULC change. Historical single framed aerial images dating back to the mid-1950s were used along with Geographic Information Systems (GIS) and remote sensing models (SPRING and ERDAS) to create historical land use maps. The Forecasting Scenarios of Future Land Use Change (FORE-SCE) model was applied to generate future LULC maps annually from 2006 to 2100 for the conterminous U.S. based on the four IPCC-SRES future emission scenario conditions. These land use maps were input into previously calibrated Soil and Water Assessment Tool (SWAT) models for two case study watersheds. In order to isolate effects of LULC change, the only variable parameter was the Runoff Curve Number associated with the land use layer. All simulations were run with daily climate data from 1978-1999, consistent with the 'base' model which employed the 1992 NLCD to represent 'current' conditions. Output daily maximum flows were converted to instantaneous AMF series and were subsequently modeled using a Log-Pearson Type 3 (LP3) distribution to evaluate flood risk. Analysis of the progression of LULC change over the historic period and associated SWAT outputs revealed that AMF magnitudes tend to increase over time in response to increasing degrees of urbanization. This is consistent with positive trends in the AMF series identified in previous studies, although there are difficulties identifying correlations between LULC change and identified change points due to large time gaps in the generated historical LULC maps, mainly caused by unavailability of sufficient quality historic aerial imagery. Similarly, increases in the mean and median AMF magnitude were observed in response to future LULC change projections, with the tails of the distributions remaining reasonably constant. FORE-SCE scenario A2 was found to have the most dramatic impact on AMF series, consistent with more extreme projections of population growth, demands for growing energy sources, agricultural land, and urban expansion, while AMF outputs based on scenario B2 showed little changes for the future as the focus is on environmental conservation and regional solutions to environmental issues.

Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador: