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31.
Ancient Maya settlement patterns exhibit fractal geometry both within communities and across regions. Fractals are self-similar sets of fractional dimension. In this paper, we show how Maya settlement patterns are logically and statistically self-similar. We demonstrate how to measure the fractal dimensions (or Hausdorff–Besicovitch dimensions) of several data sets. We describe nonlinear dynamical processes, such as chaotic and self-organized critical systems, that generate fractal patterns. As an illustration, we show that the fractal dimensions calculated for some Maya settlement patterns are similar to those produced by warfare, supporting recent claims that warfare is a significant factor in Maya settlement patterning. 相似文献
32.
Francesco Vidoli Fabio Quintiliani Giorgio Ivaldi Giorgia Marinuzzi Francesco Porcelli Walter Tortorella 《Journal of regional science》2024,64(2):308-332
Homogeneous national policies can generate heterogeneous effects on the territory. This paper aims to verify the impact of the entry of single Italian municipalities into an inter-municipal association on the unitary costs of the social services supplied to the local communities. Panel cost stochastic frontier model in the presence of endogeneity has been introduced based on two pillars: a counterfactual setting to verify the aggregation effects concerning a set of similar municipalities and the use of a cost efficiency estimation methodology which considers the endogeneity of output with respect to cost. The results of our analysis show that the effects of adopting associated forms of service delivery can be very multifaceted and diversified according to the typology and the degree of implementation of the Municipal Union itself. The analysis sheds light on the effects of municipalities' organisational choices, addressing the consolidation of small municipalities not in binary terms but also—and above all—suggesting that it is the type of union that impacts the possibility of convergence towards greater cost efficiency. 相似文献
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Charlotte L. Oskam Chris Jacomb Morten E. Allentoft Richard Walter R. Paul Scofield James Haile Richard N. Holdaway Michael Bunce 《Journal of archaeological science》2011
Using ancient DNA (aDNA) extracted from eggshell of the extinct moa (Aves: Dinornithiformes) we determined the species composition and number of eggs found in a late thirteenth century earth oven feature at Wairau Bar (South Island, New Zealand) – one of New Zealand’s most significant archaeological sites. Mitochondrial and nuclear DNA signatures confirmed this oven feature contained fragments of at least 31 moa eggs, representing three moa genera: Emeus; Euryapteryx; Dinornis. We demonstrate through the genetic identification of 127 moa eggshell fragments that thickness is an unreliable character for species assignment. We also present a protocol for assessing the preservation likelihood of DNA in burnt eggshell. This is useful because eggshell fragments found in archaeological contexts have often been thermally modified, and heat significantly increases DNA fragmentation. Eggshell is widely used in radiocarbon dating and stable isotope research, this study showcases how aDNA can also add to our knowledge of eggshell in both archaeological and palaeoecological contexts. 相似文献
35.
C.C.M. Lubos S. DreibrodtO. Nelle M. KlammS. Friederich H. MellerM.J. Nadeau P.M. GrootesM. Fuchs H.-R. Bork 《Journal of archaeological science》2011
At least 15 settlement layers, deposited above each other from the early Neolithic (ca. 5300 cal BC) until Roman Imperial Times (ca. 400 cal AD), have been discovered at Niederröblingen, Germany. Constituting the longest duration of prehistoric settlement in central Europe so far known (ca. 4000 yrs), the site is thought to represent the first multi-layered settlement mound (tell?) north of the Alps. This implicates that the occurrence of settlement mound is not limited to the circum-Mediterranean area. The detailed chronology, based on archaeological, radiocarbon and OSL dating and supporting a Bayesian model, shows one clear occupational gap (early Neolithic) and a possible hiatus (Roman Times). Erosion phases of the settlement mound and the deposition of alluvial sediments (since Roman Imperial Times) in the surroundings resulted in an almost complete disappearance of the mound from the recent scenery. Being difficult to detect, similar sites might be present, undetected, in central Europe. Their discovery and study would enable the precise reconstruction of the settlement history as well as of the prehistoric man–environmental interactions at a high resolution. 相似文献
36.
Tobias Lauer Rainer Bonn Manfred Frechen Magret C. Fuchs Marcus Trier Sumiko Tsukamoto 《Geochronometria》2011,38(4):341-349
Due to the construction of a new North-South subway in Cologne, Roman time harbour sediments were exposed and were sampled
for luminescence dating. A very good independent age control was given by the precise knowledge of the chronology of Roman
activity and by radiocarbon ages of charcoal samples. Hence, different methodological approaches within luminescence dating
were applied for Holocene heterogeneously bleached fluvial samples and were compared to the known ages. For one sample, optically
stimulated luminescence (OSL) dating was applied to coarse-grained quartz using a single aliquot regenerative-dose (SAR) protocol.
After De-measurements, different statistical approaches were tested (i.e. arithmetic mean, median, minimum age model, finite mixture
model, leading edge method and the Fuchs and Lang approach). It is demonstrated that the Fuchs and Lang approach along with
the leading edge method yielded the best matching OSL ages with respect to the known ages. 相似文献
37.
Chuang-Sheng Walter Yang Reginald DesRoches Glenn J. Rix 《Journal of Earthquake Engineering》2013,17(4):579-594
This study develops seismic fragility curves for vertical-pile-supported wharves commonly found in the western United States. Nonlinear time-history analyses of a two-dimensional numerical model under two ground motion suites are performed. The results show that the jumbo container cranes increase by 10.8% in the wharf deck drift. By using the experiment-based limit states, the proposed fragility curves demonstrate that, at a PGA of 0.50 g, the probabilities of exceeding slight, moderate, extensive, and complete limit states are approximately 23.0%, 7.0%, 4.0%, and 3.0%, respectively, while at a PGA of 1.00 g, the exceeding probabilities increase to 44.0%, 19.0%, 14.0%, and 11.0%, respectively. 相似文献
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Walter Lipgens 《History of European Ideas》2013,39(1):17-33
Environmental Education (EE) is broadly discussed in the Federal Republic of Germany. The different conceptions may be classified as the cognitive, the emotive, the cognitive-experiential and the system-critical model. In the article, the role of institutions in the educational system, dealing with EE, is described. Current activities in empirical research work and some findings on EE in German schools are reported. 相似文献