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Koen Deforce Ilse Boeren Sara Adriaenssens Jan Bastiaens Luc De Keersmaeker Kristof Haneca Dries Tys Kris Vandekerkhove 《Journal of archaeological science》2013
A detailed study of charcoal burning activities has been made for the Zoersel forest (Northern Belgium) based on an inventory of charcoal kiln remains, the analyses of wood charcoal and other charred botanical macroremains and radiocarbon dating of 10 of these kilns. Age determination of the youngest kilns was refined by dendrochronological analysis of trees growing on top of these kiln sites. The results show that, although many kilns were found, charcoal was produced in Zoersel only at certain moments during late and post-medieval times suggesting that charcoal burning was not a part of the regular management practice of these forests. The wood used for the production of charcoal mainly consists of taxa of alluvial (alder) forests while the kilns are situated on sites that currently are rather dry, with an oak dominated vegetation. For the older kilns, this contrast could be explained by an important change in local soil conditions. The younger kilns may be related to the conversion of alder woodland to grassland in the lower parts of the domain, with the kilns being constructed in the nearby dryer woodland areas. 相似文献
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Jean‐Luc Arnaud 《Imago Mundi: The International Journal for the History of Cartography》2013,65(1):46-70
Abstract De manière générale, la cartographie des villes de l'empire ottoman est peu abondante. Au dix‐neuvième siècle, malgré plusieurs réformes administratives, l'autorité publique ne recourait pas à des documents cartographiques pour organiser les travaux d'édilité tandis que les étrangers rencontraient les plus grandes difficultés pour établir des représentations de ces villes. Damas constitue une exception à ce tableau. On dispose de plusieurs cartes antérieures à l'établissement du mandat français (1920) qui sont de qualité inégale. Les auteurs étrangers sont les plus nombreux et les plus fiables; le plus souvent archéologues ou historiens, ils ont dressé des documents partiels par toujours faciles à évaluer. Cependant, et malgré la faiblesse de son volume (sept documents), le corpus des premières cartes de Damas constitue une source essentielle pour l'histoire du développement spatial de la ville entre le milieu du dix‐neuvième siècle et l'établissement du pouvoir mandataire. 相似文献
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M. Lucía Balarino 《Alcheringa: An Australasian Journal of Paleontology》2013,37(3):317-337
The first palynozonation for Permian strata of the Claromecó Basin (Argentina) is formally proposed, based on palynological assemblages recovered from the UTAL.CMM1 La Estrella.x-1 and UTAL.CMM1 Cruz de Sur.x-1 boreholes, drilled on the Argentinian Continental Platform and correlation with established zones from neighbouring basins. Fifty-five samples were analyzed and 131 species identified from two biozones. The lower Converrucosisporites confluens–Vittatina vittifera (CV) Zone occurs in the Piedra Azul and Bonete formations of both boreholes. This zone can be assigned a Cisuralian–Guadalupian age. The upper Tornopollenites toreutos–Reduviasporonites chalastus (TC) Zone registered in the Tunas Formation can be assigned a Guadalupian–Lopingian age. The CV Zone is dominated by diverse non-taeniate bisaccate, plicate and taeniate pollen. Monosaccate and monosulcate pollen, algae and acritarchs are poorly represented in both biozones. The composition of the TC Zone is broadly similar to the CV Zone, but bisaccate pollen grains are markedly more diverse and abundant in the former. 相似文献
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Stochastic Efficiency of Bayesian Markov Chain Monte Carlo in Spatial Econometric Models: An Empirical Comparison of Exact Sampling Methods
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Spatial econometric specifications pose unique computational challenges to Bayesian analysis, making it difficult to estimate models efficiently. In the literature, the main focus has been on extending Bayesian analysis to increasingly complex spatial models. The stochastic efficiency of commonly used Markov Chain Monte Carlo (MCMC) samplers has received less attention by comparison. Specifically, Bayesian methods to analyze effective sample size and samplers that provide large effective size have not been thoroughly considered in the literature. Thus, we compare three MCMC techniques: the familiar Metropolis‐within‐Gibbs sampling, Slice‐within‐Gibbs sampling, and Hamiltonian Monte Carlo. The latter two methods, while common in other domains, are not as widely encountered in Bayesian spatial econometrics. We assess these methods across four different scenarios in which we estimate the spatial autoregressive parameter in a mixed regressive, spatial autoregressive specification (or, spatial lag model). We find that off‐the‐shelf implementations of the newer high‐yield simulation techniques require significant adaptation to be viable. We further find that the effective sizes are often significantly smaller than nominal sizes. In addition, we find that stopping simulation early may understate posterior credible interval widths when effective sample size is small. More broadly, we suggest that sample information and stopping rules deserve more attention in both applied and basic Bayesian spatial econometric research. 相似文献
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Based on a large number of Monte Carlo simulation experiments on a regular lattice, we compare the properties of Moran's I and Lagrange multiplier tests for spatial dependence, that is, for both spatial error autocorrelation and for a spatially lagged dependent variable. We consider both bias and power of the tests for six sample sizes, ranging from twenty-five to 225 observations, for different structures of the spatial weights matrix, for several underlying error distributions, for misspecified weights matrices, and for the situation where boundary effects are present. The results provide an indication of the sample sizes for which the asymptotic properties of the tests can be considered to hold. They also illustrate the power of the Lagrange multiplier tests to distinguish between substantive spatial dependence (spatial lag) and spatial dependence as a nuisance (error autocorrelation). 相似文献
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ABSTRACT In this paper, we introduce a new spatially constrained clustering problem called the max‐p ‐regions problem. It involves the clustering of a set of geographic areas into the maximum number of homogeneous regions such that the value of a spatially extensive regional attribute is above a predefined threshold value. We formulate the max‐p ‐regions problem as a mixed integer programming (MIP) problem, and propose a heuristic solution. 相似文献
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Wendy van Duivenvoorde Bruce Kaiser Luc Megens Wilhelm van Bronswijk 《Post-Medieval Archaeology》2013,47(2):269-290
SUMMARY: The Dutch East India Company ship Zuiddorp (also known as Zuytdorp) met its demise in 1712 at the base of steep cliffs along the Western Australian coast. Material from the shipwreck includes an extraordinary example of a caryatid herm from the ship’s stern counter. A recent study of this sculpture and the pigments found on its surface demonstrates Zuiddorp’s archaic stern construction and adornment, which is more of a late 17th-century, than an early 18th-century, Dutch Indiaman. This paper discusses the results of this study and emphasizes how the smallest pieces of evidence can broaden our understanding of contemporaneous regional Dutch East India Company shipbuilding practices. 相似文献
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Renaud Joannes-Boyau 《Geochronometria》2013,40(4):322-333
In the context of human evolution, fossil remains are too valuable to be destroyed and any alteration should be kept to a minimum. The newly developed protocol on fossil fragments has open the gate for ‘virtually’ non-destructive ESR (Electron Spin Resonance) direct dating of human remains. The method allows the separation of unstable and interfering signals that were responsible for large dose underestimation. While a complete investigation of the ESR signal remains a complex task and requires numerous hours of manipulations, a rapid dose assessment protocol can be achieve without compromising the accuracy nor the integrity of the sample. The new protocol should be used for future dating regardless of the possibility of measuring powder. 相似文献