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Hans Ame Jensen: Seeds and Other Diaspores in Soil Samples from Danish Town and Monastery Excavations, dated 700–1536 AD. Det Kongelige Danske Videnskabernes Selskab. Biologiske Skrifter 26, Copenhagen 1986. 107 pp, 11 Tables, 10 Figs. 5 Pl.

R. Haaland &; P. Shinnie (eds.): African Ironworking: Ancient and Traditional. Norwegian University Press 1985. 212 pp.  相似文献   
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Presents three brief case studies to show how cognition and psychic activity were explored as energetic and economic transactions in a variety of experimental settings. First, in the 1870's German psychiatrist Emil Kraepelin began a search for an objective measurement of cognitive performance in which he engaged for several decades. His investigations resulted in a graphic representation of cognitive efficiency, the Arbeitscurve, delineating numbers of additions per time interval in close resemblance to representations of machine efficiency. Second, at the turn of the century American nutrition scientist and agronomist Wilbur Olin Atwater convinced himself in a series of precision measurements that the human motor was a perfectly closed input-output system and that any mental surplus in the form of cognitive energy transformation did not count as contradictions to the principle of the conservation of energy. Third, at the beginning of the 20th century and on the basis of Atwater's results, German psychiatrist Hans Berger stipulated a special form of psychic energy for mediating between the principle of the conservation of energy and mental causality. Berger attempted to quantify psychic energy as one factor of brain metabolism. In the three cases of precision investigations into psychic life presented here, the experimental space of psychophysiology turned mental activity into a form of machine-like behavior.  相似文献   
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Is urbanization good for the environment? This paper establishes a simple core–periphery model with monocentric cities, which comprises key forces that shape the structure and interrelation of cities to study the impact of the urban evolution on the environment. We focus on global warming and the potential of unfettered market forces to economize on emissions. The model parameters are chosen to match the dichotomy between average “large” and “small” cities in the urban geography of the United States, and the sectoral greenhouse gas emissions recorded for the United States. Based on numerical analyzes we find that a forced switch to a system with equally sized cities reduces total emissions. Second, any city driver which pronounces the asymmetry between the core and the periphery drives up emissions in the total city system, too, and the endogenous adjustment of the urban system accounts for the bulk of the change in emissions. Third, none of the city drivers gives rise to an urban environmental Kuznets curve according to our numerical simulations. Finally, the welfare‐maximizing allocation tends to involve dispersion of cities and the more so the higher is the marginal damage from pollution.  相似文献   
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This paper analyzes the relationship between spatial mobility and social mobility. It develops a two‐skill‐type spatial equilibrium model of two regions with location preferences where each region consists of an urban area that is home to workplaces and residences and an exclusively residential suburban area. The paper demonstrates that relative regional social mobility is negatively correlated with segregation and inequality. In the model, segregation, income inequality, and social mobility are driven by differences between urban and residential areas in commuting cost differences between high‐skilled and low‐skilled workers, and also by the magnitude of taste heterogeneity.  相似文献   
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