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51.
W. C. Mahaney 《Archaeometry》2013,55(6):1196-1204
The title of Kuhle and Kuhle's (2012) (hereafter K&K 2012) paper in Archaeometry appears to be mostly a tirade against the Traversette Route of Hannibal's Army, as originally favoured by Sir Gavin de Beer—a man possessed of singular scientific experience and near‐singular interest in Carthaginian history—in the mid‐part of the last century. The mere fact that Mahaney et al. (2010a,c) added to de Beer's corpus of evidence that Hannibal followed the southern route appears to have brought K&K (2012) to lodge not only a protest, but one of accusatory tone, stating that Mahaney et al. (2010c) had erroneously misinterpreted historical texts to prove the Col de la Traversette as the Punic Army col of passage into Italia. Aside from the fact that the tone of these allegations rises to a curious level, it is the intention of this discussion to put facts where they belong, rooted in what is known of the Hannibalic Invasion and what is inferred by the prevailing scientific evidence. It is important to note that there is not one preferred route as stated by K&K (2012), but three in fact (see Fig. 1 (a) in Mahaney et al. 2010c), and all have been discussed by a legion of historians (see, e.g., Freshfield 1886, 1899; de Beer 1969; Proctor 1971; Prevas 1998; Mahaney 2008).  相似文献   
52.
Changes in resource use over time can provide insight into technological choice and the extent of long-term stability in cultural practices. In this paper we re-evaluate the evidence for a marked demographic shift at the inception of the Early Iron Age at Troy by applying a robust macroscale analysis of changing ceramic resource use over the Late Bronze and Iron Age. We use a combination of new and legacy analytical datasets (NAA and XRF), from excavated ceramics, to evaluate the potential compositional range of local resources (based on comparisons with sediments from within a 10 km site radius). Results show a clear distinction between sediment-defined local and non-local ceramic compositional groups. Two discrete local ceramic resources have been previously identified and we confirm a third local resource for a major class of EIA handmade wares and cooking pots. This third source appears to derive from a residual resource on the Troy peninsula (rather than adjacent alluvial valleys). The presence of a group of large and heavy pithoi among the non-local groups raises questions about their regional or maritime origin.  相似文献   
53.
The concept of equivalent linearization of nonlinear system response as applied to direct displacement-based design is evaluated. Until now, Jacobsen's equivalent damping approach combined with the secant stiffness method has been adopted for the linearization process in direct displacement-based design. Four types of hysteretic models and a catalog of 100 ground motion records were considered. The evaluation process revealed significant errors in approximating maximum inelastic displacements due to overestimation of the equivalent damping values in the intermediate to long period range. Conversely, underestimation of the equivalent damping led to overestimation of displacements in the short period range, in particular for effective periods less than 0.4 seconds. The scatter in the results ranged between 20% and 40% as a function of ductility. New equivalent damping relations for four structural systems, based upon nonlinear system ductility and maximum displacement, are proposed. The accuracy of the new equivalent damping relations is assessed, yielding a significant reduction of the error in predicting inelastic displacements. Minimal improvement in the scatter of the results was achieved, however. While many significant studies have been conducted on equivalent damping over the last 40 years, this study has the following specific aims: (1) identify the scatter associated with Jacobsen's equivalent damping combined with the secant stiffness as utilized in Direct Displacement-Based Design; and (2) improve the accuracy of the Direct Displacement-Based Design approach by providing alternative equivalent damping expressions.  相似文献   
54.
A solid‐phase, non‐chemical processing protocol was recently developed as a means of chemically characterizing archaeological ceramics by total reflection X‐ray fluorescence (TXRF). Following this methodology, TXRF can provide semi‐quantitative determinations for 18 elements with comparable levels of precision and accuracy for the majority of them in comparison with a clay reference material analysed by instrumental neutron activation (INAA). In order critically to assess the analytical capabilities of TXRF, a large sample set of Late Iron Age Spanish Celtiberian ceramics and modern clays was analysed both by TXRF and INAA. Semi‐quantitative chemical data provided by TXRF and quantitative data provided by INAA were subjected to commonly used multivariate statistical methods as a way of evaluating the ability of the new technique to discriminate among different compositional groups. The comparison of the two data sets shows no significant discrepancies, thereby allowing support for the same archaeological interpretation. These results suggest that TXRF has potential applicability for compositional characterization of archaeological ceramics, providing data that are useful for provenance studies.  相似文献   
55.
档案库房空气净化的研究   总被引:1,自引:0,他引:1  
为解决大面积库房的空气净化问题,利用中央空调设备的送回风循环系统,采用灭菌型空气净化专利技术对库房空气净化处理。研究结果证明,被测环境中有害气体组分明显下降,霉菌菌落均有减少。对调节空气和改善库房内的空气质量起到了良好效果。  相似文献   
56.
海洋出水的木质文物中通常会沉积硫铁化合物。打捞出水后,硫铁化合物遇到空气和水分后会发生氧化,生成硫酸以及各种硫酸盐,并引起有机质的降解。近年来,硫铁化合物对海洋出水木质文物的危害已引起广泛关注。为此,本工作阐述了硫铁化合物相关问题的研究现状,就硫铁化合物的产生原因、危害以及目前控制方法的研究进展进行了总结,同时评述了针对硫铁化合物的处理方法。  相似文献   
57.
西藏壁画表面大多刷有保护涂层。据记载,其材质主要是桐油、牛胶或清漆等。但目前,对该涂层材质科学的研究却较少,不利于后期保护修复。为配合拉卜楞寺壁画保护修复项目,本研究以衰减全反射红外光谱法(ATR-FTIR)、核磁共振氢谱法(~1H-NMR)、热裂解-气相色谱-质谱联用(Py-GC-MS)技术等分析手段,对甘肃夏河拉卜楞寺弥勒佛殿、时轮学院主殿壁画的涂层进行了分析。结果表明,两处佛殿壁画涂层可确定是一种干性油,种类与桐油较接近。但由于西藏壁画在材料和工艺上的独特性,材料老化等因素,拉卜楞寺壁画涂层在组成和结构上,与现代桐油有一定差别,表现出一定的丰富性和复杂性。后期修复,可采用性质与西藏传统涂层材料接近的干性油,例如桐油,作为新的壁画表面涂层材料。  相似文献   
58.
A new simplified procedure for estimation of floor response spectra (FRS) is proposed. This methodology enriches the most common procedures using nonlinear response-history analysis to predict FRS by including a direct multi-mode technique to estimate FRS. A novel feature of the procedure is that the coupling effect is considered to establish equivalent modal systems and the FRS are developed by incorporating capacity spectrum method in conjunction with ductility-based FRS for each modal system. Both the proposed method and the traditional method are applied to three steel moment frame structures, and a reasonable accuracy is demonstrated.  相似文献   
59.
A simplified analysis procedure for evaluating the nonlinear seismic responses of tall reinforced concrete (RC) buildings is examined in this study. It is called the Uncoupled Modal Response History Analysis (UMRHA) procedure. It can be viewed as an extended version of the classical modal analysis procedure, where the nonlinear response of each vibration mode is first computed, and they are later on combined into the total response of the structure. The procedure requires the knowledge of the modal hysteretic behavior, which can be obtained from a cyclic modal pushover analysis. The responses of four tall buildings in Bangkok to distant large earthquakes are computed by this procedure and compared with those obtained from the Nonlinear Response History Analysis (NLRHA) procedure. These four buildings have different heights—varying from 20 to 44 stories, different configurations of floor plan, and different arrangement of RC walls. The comparison shows that the UMRHA procedure is able to accurately compute the story shears and story overturning moments, floor accelerations, and inter-story drifts of all these tall buildings. The required computational effort is also extremely low compared to that of the NLRHA procedure. Moreover, since the UMRHA procedure computes the response of each individual vibration mode, it provides more understanding and insight into the complex nonlinear seismic responses of these tall buildings.  相似文献   
60.
ABSTRACT

Historical masonry structures are often located in earthquake-prone regions and the majority of them are considered to be seismically vulnerable and unsafe. Historical masonry towers are slender structures that exhibit unique architectural features and may present many inadequacies in terms of seismic performance. The seismic protection of such typologies of structures and the design of effective retrofitting interventions require a deep understanding of their behavior under horizontal loads. This paper presents the results of the seismic performance evaluation of historical masonry towers located in Northern Italy. A large set of case studies is considered, comprising a significant number of towers with high slenderness and marked inclination. First, a preliminary assessment of the dynamic behavior of the different towers is carried out through eigenfrequency analyses. Then, non-linear dynamic simulations are performed using a real accelerogram with different peak ground accelerations. A damage plasticity material model, exhibiting softening in both tension and compression, is adopted for masonry. The huge amount of results obtained from the non-linear dynamic simulations allows a comparative analysis of the towers to be performed in order to assess their seismic vulnerability and to show the dependence of their structural behavior on some geometrical characteristics, such as slenderness, inclination, and presence of openings and belfry. The evaluation of different response parameters and the examination of tensile damage distributions show the high vulnerability of historical masonry towers under horizontal loads, mainly in the presence of marked inclination and high slenderness. Some general trends of the seismic behavior of the towers are deduced as a function of the main typological features.  相似文献   
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