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71.
Hop (Humulus lupulus L.) is an ancient perennial crop plant, native to the Northern Hemisphere. The archaeological evidence dates back to at least the sixth century ad in Europe. Hop has been used for beer brewing, in sleeping draughts, as bedding and for antibacterial purposes. Less known is that hop fibres have also been used for textiles and paper. However, it is difficult to distinguish hop from other bast fibres. Here, we present a set of fibre features, which, when found together in an archaeological/historical material within a European context, provide a strong indication that the fibres are hop.  相似文献   
72.
A wide program of structural assessment has been carried out by Politecnico di Milano on the historic bell tower of the church Chiesa Collegiata in Arcisate (Varese, northern Italy). Within this context, the first part of the article summarizes the results obtained from the application of the stochastic subspace identification method to ambient response data collected in two dynamic tests, carried out in June 2007 and June 2008. Next presented is the vibration-based methodology developed for the calibration of a three-dimensional finite element model of the tower, consisting in the successive application of systematic manual tuning, sensitivity analysis, and simple system identification algorithm.  相似文献   
73.
As discussed in Part I, a large accumulation of mammalian faeces at the mire site in the upper Guil Valley near Mt. Viso, dated to 2168 cal 14C yr., provides the first evidence of the passage of substantial but indeterminate numbers of mammals within the time frame of the Punic invasion of Italia. Specialized organic biomarkers bound up in a highly convoluted and bioturbated bed constitute an unusual anomaly in a histosol comprised of fibric and hemist horizons that are usually expected to display horizontal bedding. The presence of deoxycholic acid and ethylcoprostanol derived from faecal matter, coupled with high relative numbers of Clostridia 16S rRNA genes, suggests a substantial accumulation of mammalian faeces at the site over 2000 years ago. The results reported here constitute the first chemical and biological evidence of the passage of large numbers of mammals, possibly indicating the route of the Hannibalic army at this time. Combined with the geological analysis reported in Part I, these data provide a background supporting the need for further historical archaeological exploration in this area.  相似文献   
74.
This paper reviews the literature on the identification of bird bones found in European sites. Such a review is useful both to Quaternary palaeontologists and to zooarchaeologists attempting to identify bird bones. The publications are considered systematically. We stress that the published works should not be used for identification in isolation, but that a comparative collection is essential. © 1997 John Wiley & Sons, Ltd.  相似文献   
75.
Morphological characters for the separation of red and fallow deer remains are described. These encompass antlers, permanent dentition, and postcranial bones. The characters were tested on samples of known red and fallow deer from an array of contexts, thus helping to ensure their validity across different populations. An attempt is made to quantify the reliability of each character, using a simple arithmetic method of scoring and analysing the test data. This forms the basis for a more objective assessment of the identity of an unknown specimen.  相似文献   
76.
We report on two cases of similar bony lesions and emphasize the importance of cooperative work between forensic anthropology and forensic pathology. A fairly well preserved cadaver of an old woman was autopsied by a forensic team at the National Institute of Forensic Medicine in Portugal. Although age at death and sex were easily determined, there was insufficient other evidence for personal identification. However, the female revealed severe and extensive lesions in both lower legs and these were useful for determining personal identity. Here we describe the pathological findings, consistent with venous chronic insufficiency. The woman's family subsequently confirmed she suffered from this condition. Furthermore, they informed us of varicose ulcers, which also were suspected by the ties found, in both her legs, during autopsy. A long history of venous chronic insufficiency was subsequently found in her medical records. We compare these forensic findings to the bony pathologies of a male skeleton from the Coimbra Identified Skeletal Collection not previously diagnosed. We argue that these two cases represent the same pathological condition. Without the medical forensic work, the skeletal remains of the second case might not have been positively identified. The benefits of cooperative work between medical and anthropological forensic specialists are reinforced leading to resolution of otherwise unidentified skeletal pathological conditions. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
77.
Recent excavations at the site of Kara-tepe in northwestern Uzbekistan revealed evidence for the production of cotton (Gossypium sp.) in domestic contexts dated to ca. 300–500 AD. These archaeobotanical remains help to document the spread of Old World cotton production, and predate the existing evidence for its cultivation in Central Asia. The context in which these remains were found—in temperate Eurasia at a time of intense environmental and social change—suggests that the spread of cotton agriculture to this region occurred when new plant varieties were incorporated into domestic production regimes as part of local adaptive strategies. The development and transmission of cotton as a global cultigen was initiated by these small-scale innovations aimed at the expansion of economically and environmentally sustainable subsistence practices in Central Asia. Subsequent worldwide transmission occurred when emerging empires helped to spread cotton agriculture more widely across the Old World.  相似文献   
78.
为做好太仓半泾河古船保护修复工作、了解古船造船工艺及用材习惯,对船体龙骨、隔舱板、舱底板、侧板、船尾挡板、斜撑木、补强材、桅座和护舷板等31个样品的树种进行了鉴定。结果表明:太仓古船用材包括杉木(38.7%)、香樟(32.3%)、硬松(16.1%)、枫香(9.7%)和柏木(3.2%)等5个树种。经分析,古船用材均广泛分布于中国南方,其性能适合作为船体用材,说明古人造船就地取材但不单一选材。船体树种鉴定结果有利于后期针对性地进行船体保护工作。  相似文献   
79.
The primary focus of a structural shake table system is the accurate reproduction of acceleration records for testing. However, many systems deliver variable and less than optimal performance, particularly when reproducing large near-field seismic events that require extreme table performance. Improved identification and control methods are developed for large hydraulic servo-actuated shake table systems that can exhibit unacceptable tracking response for large, near-field seismic testing. The research is presented in the context of a 5-tonne shake table facility at the University of Canterbury that is of typical design. The system is identified using a frequency response approach that accounts for the actual magnitudes and frequencies of motion encountered in seismic testing. The models and methods developed are experimentally verified and the impact of different feedback variables such as acceleration, velocity and displacement are examined.

The methods show that shake table control in testing large near-field seismic events is often a trade off between accurate tracking and nonlinear velocity saturation of the hydraulic valves that can result in severe acceleration spikes. Control methods are developed to improve performance and include both acceleration and displacement feedback to reduce the acceleration spikes, and record modification, where the reference signal is modified to conform to the shake table's operational parameters. Results show record modification gives exact tracking for near-field ground motions, and optimal system response for reference signals with velocity components greater then the system capabilities. Overall, the research presents a methodology for simple effective identification, modelling, diagnosis and control of structural shake table systems that can be readily generalised and applied to any similar facility.  相似文献   
80.
An experimental study has been conducted on a reduced-scale gravity-load designed test frame to investigate its overall performance due to the addition of steel fiber-reinforced concrete (SFRC) at the critical regions. Two geometrically similar specimens, namely, reinforced concrete (RC) and SFRC, are tested under slow-cyclic lateral loading. End-hooked steel fibers (aspect ratio = 80) of 1.0% volume fraction were used in the SFRC mix for a distance of one-and-half times the member size near the joint regions. The addition of steel fibers improved the damage tolerance, lateral load resisting capacity, lateral stiffness, ductility, and energy dissipation of the frame.  相似文献   
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