A Fractal Approach to Identifying Urban Boundaries. 城市边界识别的分形方法

Fractal geometry can be used for determining the morphological boundaries of metropolitan areas. A two‐step method is proposed here: (1) Minkowski's dilation is applied to detect any multiscale spatial discontinuity and (2) a distance threshold is located on the dilation curve corresponding to a major change in its behavior. We therefore measure the maximum curvature of the dilation curve. The method is tested on theoretical urban patterns and on several European cities to identify their morphological boundaries and to track boundary changes over space and time. Results obtained show that cities characterized by comparable global densities may exhibit different distance thresholds. The less the distances separating buildings differ between an urban agglomeration and its surrounding built landscape, the greater the distance threshold. The fewer the buildings that are connected across scales, the greater the distance threshold.     

Testing for Spatial Independence Using Similarity Relations

In this article, we construct new, simple, and nonparametric tests for spatial independence using symbolic analysis. An important aspect is that the tests are free of a priori assumptions about the functional form of dependence, making them especially suitable in situations where the dependence is nonlinear. We define the concept of a similarity relation, which is used to keep track of similarity between neighboring observations. This similarity count is used to construct new statistical tests based on both random permutation simulations and derived asymptotic distributions. We include a Monte Carlo study to better illustrate the properties and the behavior of the new tests under several synthetically generated processes. Apart from being competitive compared with other nonparametric and parametric tests, results underline the outstanding power of the new tests for nonlinear‐dependent spatial processes.     

Archaeological implications of human-derived manganese coatings: a study of blackened bones in El Mirón Cave,Cantabrian Spain

The main interest in the study of taphonomic processes lies, from the archaeological point of view, in being able to draw conclusions about human behaviour from them. This paper analyzes the causes of a specific taphonomic alteration: the differential appearance across levels and among site areas of a black stain on bones from the Magdalenian levels in El Mirón Cave. From an understanding of these taphonomic agents, we aim to achieve a better comprehension of aspects of human use of the cave toward the end of the Late Glacial period. By determining the processes that stained many of the bones with manganese in the rear part of the cave vestibule, we are able to suggest some characteristics of the human occupation of the cave and its possible seasonal use.     

Rock surface luminescence dating of prehistoric rock art from central Iberia

Rock art paintings are notoriously difficult to date numerically. Recently, luminescence dating has been shown to provide reliable rock surface burial ages in various archaeological settings. Here we use the cross-cutting relationship between a fallen rock and two paintings of the Iberian Levantine (older) and Schematic (younger) styles to constrain the age of the paintings by dating the rockfall event using rock surface luminescence dating. Infrared-stimulated luminescence (IRSL) signals as a function of depth into the buried face of the talus border indicate that the IRSL signal measured at 50°C (IR₅₀) was sufficiently reset to a depth of about 1.6 mm prior to burial. An uncorrected IR₅₀ age of 1.6 ± 0.2 ka was calculated for the rockfall event by dividing the surface equivalent dose (D_e) by the total dose rate. This age was corrected using both conventional and field-to-laboratory saturation approaches to yield indistinguishable ages of 2.7 ± 0.5 and 2.9 ± 0.3 ka, respectively. Since the panel with Schematic art was first available to the artist after the rockfall, we conclude the Schematic rock art at Villar del Humo is younger than ~2.9 ka. The Levantine rock art was painted on a panel constrained by the talus boulder before detachment, and so it is likely to be older than ~2.9 ka.     

Anselm Kiefer: a study of his artistic materials

The style of the contemporary German artist Anselm Kiefer is highly innovative and unconventional and is characterized by the use of diverse materials that he selects and combines according to the emotions that they stir in him. The conservation and preservation of works by Kiefer are particularly difficult tasks because of the heterogeneity and, in some cases, the incompatibility of the materials used; therefore, a thorough characterization is crucial before any intervention is considered. In this paper, we report the results of an investigation on a fragment from a multimaterial work and on samples from the paintings Bohemia Lies by the Sea and Die Größe Fracht. The large fragment was cut by the artist himself from a work in progress and is considered destitute of any artistic value; therefore, it was possible to sample it extensively. This fragment and the samples from the Die Größe Fracht and Bohemia Lies by the Sea paintings were analyzed by ultraviolet (UV) fluorescence imaging, fiber optic reflectance spectroscopy, Fourier transform infrared spectroscopy, nuclear magnetic resonance, Raman spectroscopy, X-ray diffraction, gas chromatography-mass spectrometry, and pyrolysis gas chromatography-mass spectrometry. This multitechnique approach allowed us to fully characterize and identify pigments, dyes, and organic components that reflect the diversity of the materials typically chosen by the artist. The results are evaluated in the context of the interview that Antonio Rava had with the Anselm Kiefer in 2000.