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In the past decade Tobler has provided an innovative cartographic presentation of migration flows. The central theme of this research has been to utilize detailed migration data to reveal the underlying structures of migration flows. Even though the analyses are not explanatory models of migration exchanges, the application of these techniques to migration flows over time and across different spatial scales provides a visual generalization of often extremely complex flows. The application of his techniques at two spatial scales for the Netherlands illustrates both the strengths and weaknesses of migration force fields for the analysis of migration.  相似文献   
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Cryptocrystalline silicates from the Chadron Formation were widely used by prehistoric human groups in the Great Plains of North America. There are two documented quarry areas: Flattop Butte in Colorado and the White River Badlands of South Dakota. Cryptocrystalline silicates from these sources are visually indistinguishable, making it difficult to determine the sources of artefacts found at archaeological sites. In this investigation, neutron activation analysis is used to distinguish the two sources. This technique also identifies lithic material from the Clovis-age Eckles site in Kansas as being from Flattop Butte.  相似文献   
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Spatial compactness has been proposed as a suitable criterion for assessing whether electoral boundaries reflect partisan interests. Although several different measures of spatial compactness have been developed, only limited efforts have been made to compare and evaluate them in the context of electoral redistricting. This paper assesses alternative spatial compactness measures and applies conceptually appealing measures to the provincial ridings proposed by British Columbia's Royal Commission on Electoral Boundaries (1988).  相似文献   
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Books reviewed in this article:
A. Comments
B. Book Notes
Abney, Glenn and Thomas P Lauth The Politics of State and City Administration
Adams, William J and Christran Stoffaes, (eds) French Industrial Policy
Binkin, Martin, Military Technology and Defense Manpower
Elazar, aniel J Cities of the Prairie Revisited The Closing of the Metropolitan Frontier
Ginsberg, Benjamin The Captive Public How Mass Opinion Promotes State Power
Heath, Robert L and Richard Alan Nelson Issues Management Corporate Public Policymaking in an Information Society
Hunt, Morton Profiles of Social Research The Scientific Study of Human Interactions
Kaplan, Marshall and Peggy Cuciti (eds) The Great Society and itsLegacy wenty Years of U S Social Policy
Katz, Michael B In the Shadow of the Poorhouse A Social History of Welfare in America
Katzmann, Robert A. Institutional Disability The Sage of Transporation Policy for the Disabled
Liroff, Richard A Reformaing Air Pollution Regulation The Toil Trouble of EPA's Bubble
Lowi, Theodore J The Personal President Power Invested Promise Unflfilled
Mead, Walter J, Asbjorn Moseidjord, Dennis D Muraoka, and Philip E Sorenson Offshore Lands. Oil and Gas Leasing and Conservation on th Outer Continental Shelf
Muskie, Edmund, Kenneth Rush, and Kenneth W Thompson The President, the Congress and Foreign Policy
Openshaw, Stan Nuclear Power. Siting and Safety
Peters, B Guy American Public Policy Promise and Performance
Rosentraub, Mark S, (ed) Urban Policy Problems Federal Policy and Institutional Change
Story, Dale Industry, the State, and Public Policy in Mexico
Taylor, Ralph B, (ed) Urban Neighborhoods Research and Policy
Wesson, Robert and Heraldo Munoz, (eds) Latin American Views of U S Policy
Winston, Brian isunderstanding Media
Zurcher, Louis A, Milton L Boykin, and Hardy L Merritt Citizen Sailors in a Changing Society Policy Issues for Manning the United StatesNaval Reserve  相似文献   
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An ecological model is proposed for human responses to climatic seasonality in the later Holocene of the southwestern Cape in South Africa. This is an area where pronounced seasonality produces cyclical effects on plant, animal and human communities. The predictions of this model are that: 1. human foragers would switch from plant carbohydrates to seal fat as a winter energy source; 2. capture and butchery of seals would vary with season and seal age; 3. capture and butchery of ungulates would vary seasonally; and 4. seals would be exploited differently from ungulates throughout the year. The model is tested against faunal data from Smitswinkelbaai Cave.
Résumé On propose un modèle écologique des réactions humaines à la saisonalité climatique pour l'Holocène récent dans le cap sud-ouest, Afrique du Sud. C'est une région où la saisonalité produit des effets cycliques sur les communautés végétale, animale et humaine. Les prédictions de ce modèle sont les suivantes: 1. les cueilleurs humains changeaient des féculents végétaux à la graisse de phoque comme source d'énergie en hiver; 2. la prise et la boucherie de phoques variaient avec les saisons et selon l'âge des phoques; 3. la prise et la boucherie des ongulés variaient de façon saisonnière; et 4. les phoques étaient exploités différemment des ongulés pendant toute l'année. On présente un essai préliminaire du modèle sur les données de la caverne Smitswinkelbaai.
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