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51.
Abstract

Archaeological field survey is the basic method for determining the history of settlement on the regional level. The backbone of survey is locating and surveying individual sites, estimating their size, and uncovering their settlement histories. Various biases place doubt on the reliability of surface data and the conclusions drawn from them. This study presents three methods for investigating multiperiod sites in eastern Galilee, Israel: advanced surface survey, shovel test sampling, and large-scale stratigraphic excavations. Advanced surface survey was carried out at 46 sites settled during the Hellenistic through Byzantine periods (ca. 300 b.c.a.d. 650). Three of these sites were later sampled using shovel test pits. Large-scale excavations were conducted at two of these sites, Khirbet Wadi ?amam and Nasr ed-Din enabling the comparison of the three methods. Applying these three methods to the same sites allowed us to evaluate the advantages and disadvantages of each method for determining settlement history. The results indicate that a thorough surface survey of a site in an area where local pottery is well documented can provide a clear picture of its occupation history. However, these data are not sufficient to determine variations in the size of the site over time. Shovel test sampling presents no advantage over surface survey with regard to documenting periods of activity at a given site, but it is preferable for tracing changes in the intensity of occupation during different periods. Excavation is the most informative method, but because it is costly and time consuming, it often sheds light only on small portions of selected sites.  相似文献   
52.
On the 200th anniversary of Johann August Philipp Gesner's death, this paper summarizes and discusses a paper on language amnesia published in 1770. The author had clear knowledge of selective mental impairments resulting from brain diseases, and of separate mental representations for words and their underlying concepts. However, to explain the language impairment, Gesner suggested that it would not be caused by focal damage to a specific anatomic and functional unit of the mind, but is the consequence of a general sluggishness of the mental processes.  相似文献   
53.
The Early Bronze Age barrows at Irthlingborough and Gayhurst in central England are notable for the large number of cattle (Bos taurus) remains associated with their human Beaker burials. Previous work using strontium isotope analysis has indicated that most of the cattle analysed, and one aurochs (Bos primigenius), were of local origin [Towers, J., Montgomery, J., Evans, J., Jay, M., Parker Pearson, M., 2010. An investigation of the origins of cattle and aurochs deposited in the Early Bronze Age barrows at Gayhurst and Irthlingborough. Journal of Archaeological Science 37, 508–515.]. In this study, stable isotope analysis of enamel and bone was carried out to investigate whether the mature cattle had experienced similar husbandry practices, climate and environment. Bulk carbon, nitrogen and sulphur isotope analysis of collagen suggested most were consuming similar sources of plant protein from environments probably local to the sites and this was supported by high resolution intra-enamel carbon isotope profiles. Oxygen isotope profiles indicated the aurochs and most of the cattle experienced similar climatic regimes: the only exception being an animal with a non-local strontium isotope ratio. However, a comparison of seasonality profiles of the local animals using estimated tooth formation times showed that there was no consistency in season of birth: the animals appeared to have been born throughout the year. Cattle can breed throughout the year but it requires considerable human effort and intervention to successfully overwinter young stock; it is therefore unlikely to have been carried out without good reason and benefit if winters were harsh. One reason is to ensure a continuous supply of milk. Measuring oxygen isotope profiles to identify year-round calving may thus be a potential indicator of dairying economies.  相似文献   
54.
This paper reports the results of a study into the effectiveness of core sampling for discovering Palaeolithic and Mesolithic hunter-gatherer sites in the Netherlands and northwestern Belgium. Earlier work established optimal sampling strategies for use in archaeological heritage management survey in the Netherlands. However, the statistical model used for this was based on a limited amount of data on the distribution of lithic artefacts in Palaeolithic and Mesolithic sites. For the current study we have analyzed the distribution of artefacts in a selected number of excavated sites, and estimated discovery probabilities of these sites through simulation. The simulation results indicate that discovery probabilities are lower than expected due to the effect of clustering of finds. Furthermore, the density of flints in Palaeolithic and Mesolithic sites is generally lower than the estimates that were used for setting up the optimal sampling strategies, and a substantial number of sites is very small. This means that, in order to discover Palaeolithic and Mesolithic sites with sufficient reliability, we will have to apply more intensive survey strategies than have been recommended up to now.  相似文献   
55.
Nubian biological evolution has come under much scrutiny in preceding years with strong opinions dividing scholars' beliefs as to how it occurred. A new approach is necessary to elucidate subtleties of their population structure in order to shed light on the complex subject. This study employs a spatial–temporal model in an effort to test if in situ biological evolution was the mechanism for biological change. Biological distance was calculated from the phenotype using 20 cranial discrete traits observed in Nubian samples from the sites of Semna South, Kerma, and the islands of Hesa and Biga. The periods represented at Semna South are Meroitic, X‐Group and Christian, whereas the Kerma site yielded skeletal material from the Kerma period, and the islands of Hesa and Biga date to the Christian period. Mahalanobis D2 with a tetrachoric matrix was used to calculate biological distances among the samples, and three‐way Mantel tests were applied to the distance, spatial and temporal matrices. Time was not significantly correlated with biological distance. However, an inverse relationship of time and biological distance is expected under the spatial–temporal model. A lack of significant geographic correlations, as found here, is unusual in most populations, but given the spatial construct of the sites along the Nile, this relationship is not completely unexpected. The lack of significant correlation among time, space and biological distance does not support the in situ hypothesis. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
56.
ABSTRACT

Despite the high vulnerability of historic structures to earthquakes, the approaches for evaluating seismic demand and capacity still appear inadequate and there is little consensus on the most appropriate assessment methods to use. To develop an improved knowledge on the seismic behavior of masonry structures and the reliability of analysis tools, two real-scale specimens were tested on a shake table, and several experts were invited to foresee failure mechanism and seismic capacity within a blind prediction test. Once unveiled, experimental results were simulated using multi-block dynamics, finite elements, or discrete elements. This article gathers the lessons learned and identifies issues requiring further attention. A combination of engineering judgment and numerical models may help to identify the collapse mechanism, which is as essential as it is challenging for the seismic assessment. To this purpose, discrete modeling approaches may lead to more reliable results than continuous ones. Even when the correct mechanism is identified, estimating the seismic capacity remains difficult, due to the complexity and randomness of the seismic response, and to the sensitivity of numerical tools to input variables. Simplified approaches based on rigid body dynamics, despite the considerable experience and engineering judgment required, provide as good results as do advanced simulations.  相似文献   
57.
ABSTRACT

The analysis of the shaking table test of a 3-wall stone masonry structure performed with a discrete element model is presented. The numerical model, created with the code 3DEC, employed a rigid block representation and a Mohr-Coulomb joint model. Joint stiffness calibration to match the experimental natural frequencies is discussed, as well as the boundary conditions to simulate the shake table. Comparisons are made with the measured displacements at key locations, and the modes of deformation and fracture of the walls. The DEM model was able to reproduce important features of the shaking table tests. The experimental deformation and near collapse patterns were clearly identifiable in the numerical simulations, which produced displacements within the observed orders of magnitude, for the various levels of excitation.  相似文献   
58.
An approach to testing for modes in low-dimensional data, Silverman’s test, novel in an archaeological setting, is described and illustrated. ‘Patterns’ in archaeological data can be suggested by the presence of modes. Reassurance is needed that modes suggested by graphical analysis are genuine before attempting substantive archaeological interpretation. The test either provides such reassurance, or else guards against over-interpretation, particularly with small samples. Data on loomweight dimensions, lead isotope ratios, and ceramic compositions are used to illustrate use of the test, dealing with issues concerning outliers and small samples as they arise. The focus is on univariate mode detection.  相似文献   
59.
锡铅钎料和氯化锌钎剂的烙铁钎焊是传统的工艺方法。由于氯化锌钎剂中含有大量的氯离子,对青铜物的长期保存带来不利的影响。本工作通过对钎剂筛选和复配及钎料的选择,研制了针对青铜物修复钎焊用新型无氯钎剂和含银钎料匹配,并在8种古青铜模拟试样上进行一系列性能测试,结果表明新型无氯钎剂和含银钎料匹配有良好的工艺性、抗腐蚀性、可获得高强度的钎缝。新型无氯钎剂和含银钎料匹配在青铜物修复中应用结果表明,新型无氯钎剂和含银钎料有较好的钎焊工艺,钎焊接头饱满光亮,对于不同时期及不同合金的青铜物具有很好的钎焊性,钎焊后青铜物存放半年,钎焊接头依然保持光亮,焊缝周围没有出现锈蚀物和氧化现象。用新型无氯钎剂替代传统氯化锌钎剂,并且和含银钎料匹配进行古青铜的钎焊是可行的,改良后的钎剂进行青铜物修复过程符合物保护原则,避免了钎剂在钎焊过程中产生的气体对操作人员身体健康的影响。  相似文献   
60.
为了寻找适合博物馆柃测要求的NO2测定方法,选择分子筛为填充担体,TEA与DEA为复配吸收剂,采样管柱长为5cm,管径为5.5mm,采样流速为100—160ml/min,建立了固体主动采样法。经与常规溶液法和仪器法测定结果比较,三种采样法测得的NO2浓度在精密度和总体均值上均无显性差异,具有高度相关性和可比性。它们之间的回归直线关系存在,可用于环境现场二氧化氮的检测。  相似文献   
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