基于后人类思想的国际城市研究：理论溯源与概念辨析

进入二十一世纪以来,以赛博格城市、混合城市、城市政治生态学、集合城市主义为代表的后人类城市研究思想成为揭示当代城市中人类与非人类复杂交织关系的前沿性理论视角。本文在深入探讨上述概念的理论渊源、主要思想观点及其应用进展的基础上,指出后人类城市思想在我国城市研究中的可能方法论意义,即城市分析不能将人类与非人类绝对割裂地看待,而需要将城市中的主体或客体重新定义为人类与非人类的“混杂体”,整合以往分散在自然、工程、社科与人文等不同领域中的观察与分析,拓展人们对城市过程的认知,开创更多的城市研究可能性。     

FOUNDATIONS OF THE CADES POND CULTURE IN NORTH-CENTRAL FLORIDA: THE RIVER STYX SITE (8AL458)

The River Styx site was an important Middle Woodland ceremonial center in north-central Florida that included a horseshoe-shaped earthen embankment, a burial mound containing only cremations, and diverse nonlocal artifacts. The site was recorded more than forty years ago but a report was never written. This article presents a summary of excavation results at River Styx and analysis of the pottery assemblage based on archived notes and collections at the Florida Museum of Natural History. From the pottery assemblage, 24 vessel lots, consisting of mostly partially reconstructed vessels, are described in terms of form, surface treatment, and mineralogical constituents characterized by petrographic analysis. The provenance of each vessel is inferred, and more than half of the analyzed assemblage is judged to be nonlocal.     

摄影铭

<正>仿唐代诗人刘禹锡《陋室铭》习作,以此献给老年摄影爱好者——片不在佳,得心则名。具不在精,应手则灵。斯是光艺,唯吾痴心。孤芳当自璐,百艳汇群星高师同知己,影友胜亲朋。可以品自然,赏百景。无乱事     

A PROCEDURE FOR ESTIMATING INPUT ENERGY SPECTRA FOR SEISMIC DESIGN

In this paper, the damage potential of an earthquake ground motion is evaluated in terms of the total power of the acceleration of the ground motion. By assuming an appropriate spectral shape for the input energy spectrum, and using the well-known Parseval theorem for evaluating the total power of a random signal, the peak amplification factor for the equivalent input energy velocity spectrum can be determined. It is shown that the peak amplification factor for the input energy spectrum depends on the peak-ground-acceleration to peak-ground-velocity ratio and duration of the strong motion phase of the ground motion. Values for the equivalent input energy velocity amplification factor vary from about 2 to 10 for most of the recorded ground motions used in this study. Although a considerable scatter of data is observed in this study, the peak amplification factor predicted by the Fourier amplitude spectrum of the ground acceleration provides a fairly good estimate of the mean value of the peak input energy compared to that determined from inelastic dynamic time history analyses, particularly for systems with high damping and low lateral strength. The peak amplification factor derived in this paper provides a more consistent approach for estimation of seismic demand when compared to an earlier empirical expression used for the formulation of duration-dependent inelastic seismic design spectra, even though only a slight difference in the required lateral strength results from the use of the new formula.     

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