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71.
Iron-57 Mössbauer absorption spectra have been measured for samples of obsidian from known geological flows and from archaeological site material from the western Mediterranean region. Of the four main sources available to prehistoric man it is possible to distinguish Sardinian (SA) and Pantellerian obsidian from Lipari obsidian on the basis of differences in the local atomic surroundings of iron atoms, as determined from the Mössbauer spectra. There is, however, some overlap between Lipari and Pontine Island obsidians. The Gabellotto flow on Lipari is readily identified through the presence of magnetite inclusions. The ratio of ferric to ferrous ions is found to be much higher in the surface layers (< 60 μm) than in the bulk obsidian as detected using Mössbauer backscattering.  相似文献   
72.
This paper examines the usefulness of bootstrapping in Correspondence Analysis when applied to archaeological data. By simulating and displaying possible variation within the data sets, bootstrapping provides us with a means to assess the stability of our CA maps and influences the interpretations we can place upon them. Five real data sets are examined and the results discussed. The paper concludes that bootstrapping is a useful and powerful way of examining the results of CA and should be employed on a regular basis.  相似文献   
73.
This study discusses the materials and traditional knowledge used in the manufacture and application of lime mortars and stuccoes by Romans and Arabs in Seville (southern Iberian Peninsula). All of the samples studied contain calcite as a binder, combined with aggregates based on river sand from the filling materials of the Guadalquivir River's depression, located in the vicinity of the Real Alcazar Palace in Seville, Spain, where the artefacts were discovered. The Romans used high‐quality production technology, as evidenced by the careful selection of raw materials as well as by the adequate binder‐to‐aggregate ratio and the elevated homogeneity of the mortars and stuccoes. The suitable distribution of aggregates resulted in higher density values for Roman fragments than for Arabic ones. Results derived from Arabic samples suggest a decline in technology manufacture over time. This work provides useful information, particularly regarding the Roman and Arabic periods in the Iberian Peninsula. The analytical techniques employed in this study were X‐ray diffraction (XRD), X‐ray fluorescence (XRF)—using conventional and portable systems, scanning electron microscopy (SEM), petrographic microscopy, differential thermal analysis/thermogravimetry (DTA/TG), particle‐size analysis and mercury intrusion porosimetry.  相似文献   
74.
This paper studies the relation between coalition structures in policy processes and policy change. While different factors such as policy images, learning processes, external events, or venue shopping are important to explain policy change, coalition structures within policy processes are often neglected. However, policy change happens as a result of negotiations and coordination among coalitions within policy processes. The paper analyzes how conflict, collaboration, and power relations among coalitions of actors influence policy change in an institutional context of a consensus democracy. Empirically, I rely on a Qualitative Comparative Analysis to conduct a cross‐sector comparison of the 11 most important policy processes in Switzerland between 2001 and 2006. Coalition structures with low conflict and strong collaboration among coalitions as well as structures with dominant coalitions and weak collaboration both facilitate major policy change. Competing coalitions that are separated by strong conflict but still collaborate strongly produce policy outputs that are close to the status quo.  相似文献   
75.
Prior to their restoration, the porcelain bodies of broken pieces from 31 authentic Meissen objects of the early 18th century were investigated by proton‐beam analysis. Attention was paid so that the proton beam probed only the bare porcelain paste areas of fractures. Thus, contributions to the measured X‐ray and γ‐ray spectra from adjacent surface glaze were prevented. The chemical compositions, obtained by simultaneous detection of elements with Z ≥ 13 (X‐rays) and lighter elements Z ≤ 14 (γ‐rays), represent rather consistent mixtures of paste ingredients. This result highlights the durable recipes and raw materials used in early Meissen porcelain production in the years 1725–50. Mean concentration values of element oxides, deduced from the detailed measurements, prove suitable for use as a database for Meissen porcelain paste identification. Material authentication of intact objects, without access to the bare porcelain body, is demonstrated by inspection of the white glaze. Unique museum objects are examined in atmosphere and without sampling. A low proton‐beam intensity and a short irradiation time ensure non‐destructive analysis. Simultaneous radiation and backscattered particle detection allow complete composition analysis, using the established ion beam techniques of particle‐induced X‐ray emission (PIXE), particle‐induced gamma‐ray emission (PIGE) and Rutherford backscattering spectrometry (RBS).  相似文献   
76.
The Second National Conference on Disability, held in Bari in 2003, took the World Health Organization's International Classification of Functioning, Disability and Health (ICF), adopted by all WHO member states in 2001, as its frame of reference for future action and policies on disability. The ICF broke decisively with the medical model by seeing disability as an interaction between a biological and psychological condition and environmental and attitudinal barriers. Although existing Italian legislation on access to work for persons with disabilities, particularly Law 68/1999 on ‘collocamento mirato’ (targeted placement), anticipated some of the principles and definitions of the ICF, its implementation in practice was often snared in complex bureaucratic procedures and compromised by narrowly medical assessments of impairment and by considerable variations in standard from region to region. In 2009–2011 a pilot project, Progetto ICF4, was launched in 11 regions of Italy. It applied ICF principles, using Social Network Analysis (SNA) to assess the suitability of a work environment in terms of the networks of relations between the different actors involved in it. The way this has functioned in practice is illustrated by a case study of Teramo, one of the provinces in the pilot.  相似文献   
77.
This article describes a simplified procedure for estimating the seismic sidesway collapse capacity of frame building structures incorporating linear viscous dampers. The proposed procedure is based on a robust database of seismic peak displacement responses of viscously damped nonlinear single-degree-of-freedom systems for various seismic intensities and uses nonlinear static (pushover) analysis without the need for nonlinear time history dynamic analysis. The proposed procedure is assessed by comparing its collapse capacity predictions on 272 different building models with those obtained from incremental dynamic analyses. A straightforward collapse capacity-based design procedure is also introduced for structures without extreme soft story irregularities.  相似文献   
78.
文物政策科学研究,又称文物软科学研究,是为促进文物事业宏观管理和决策的专业化、科学化和民生化提供支持、咨询、评价和反馈的综合性研究。文物事业是保护和管理国家不可再生宝贵文物资源的特殊文化行业,其政策研究具有特殊性和重大现实意义。但目前文物政策研究成果分散、水平不高,缺乏研究机构和组织规划。  相似文献   
79.
The emergence of archaeological interest in native copper in the mid-1800s developed in concert with explanations that privileged the Lake Superior area over other potential sources of copper. Most scholars have thus assumed that when copper artifacts first appeared in Northeastern North America, they arrived as finished implements or were locally made from Lake Superior raw materials. Procurement models that point to Lake Superior as the sole source of native copper have been widely accepted in the absence of systematic large-scale testing. This article evaluates the dominant model for native copper procurement and presents trace element data derived from instrumental neutron activation analysis (INAA) to determine whether hunter-gatherers in the Northeast utilized one dominant source of copper or in fact exploited a number of geological deposits. I specifically report on the chemical characterization of copper from 13 discrete geological deposits and 18 archaeological sites dating to the Late Archaic (ca. 5000–3000 B.P.) and Early Woodland (ca. 3000–2000 B.P.) periods to suggest that the dominant model for native copper procurement is oversimplified.  相似文献   
80.
The 2011 great Japan Tohoku earthquake is not only the most devastating but also, one of the best recorded earthquakes in the history of seismology. A thorough study of strong motion characteristics of this earthquake is conducted using 20 well established ground motion parameters (GMPs). The behaviour of these parameters with fault distance and average shear wave velocity is examined and attenuation relationships are developed using the 1172 surface level strong motion records. In addition, all GMPs are categorized on a statistical basis using principal component analysis, which is further used to rate the damage potential of ground motion records.  相似文献   
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