Santa Maria di Collemaggio Church (L’Aquila,Italy): Historical Reconstruction by Non-Destructive Testing Techniques

The main goal of this work was the non-destructive testing (NDT) of an ancient fresco (15th century) preserved in the Santa Maria di Collemaggio Church (L’Aquila, Italy) and damaged after the 2009 earthquake. Active infrared thermography (IRT), near-infrared (NIR) reflectography and ultraviolet imaging (UV) were used. In addition, the state of the fresco prior to the earthquake was analyzed by electronic speckle pattern interferometry (ESPI), digital speckle correlation (DSC), raking light, tap, and chemical NDT techniques. The use of these techniques was important for the monitoring of new damages and for a comparison between the results over the years. Square heating thermography (SHT) data were processed using principal component thermography (PCT) and pulsed phase thermography (PPT) algorithms, in order to improve the defects’ signature and to reduce the impact of non-uniform heating and emissivity variations due to the painting’s pigments. A multi-analysis approach, segmentation operators and a specific data correlation method emphasize the overall study of the fresco. Furthermore, the facade and the high altar area were inspected by passive thermography and ground-penetrating radar (GPR), respectively. In the present case, the combined use of NDT techniques was useful to fill in the gaps in the construction history of the building.     

我国旅游业发展与经济增长的关系研究——基于不同省份的个体数据和面板数据分析

本文利用个体数据和面板数据的VAR模型和格兰奇因果检验,分析我国各个省份和不同经济区域的旅游业发展与经济增长的关系。基本结论是：从面板数据分析来看,总体上二者之间存在一种长期均衡和双向因果关系,但旅游业发展对经济增长的贡献要小于经济增长对旅游业发展的贡献;我国不同经济区域之间二者的因果关系表现出较强的地理差异性,东部发达地区“经济增长对旅游业发展的影响”远大于“旅游业发展对经济增长的影响”,中部地区次之,西部地区因果关系正好相反,东北地区为“经济增长影响旅游业发展”的单向因果关系;从单个省份的格兰奇因果关系看,仅13个省市的LGDP和LTOUR之间存在长期均衡关系,大部分省份存在双向因果关系,但在影响强度上有较大差异。     

Determining the settlement history of Hellenistic,Roman, and Byzantine sites in the Galilee,Israel: Comparing surface,subsurface, and stratified artifact assemblages

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.     

Johann August Philipp Gesner (1738–1801). A Review of His Essay “The Language Amnesia” in The Bicentennial Anniversary of His Death

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.     

An Examination of the Spatial–Temporal Isolation Model in a Nilotic Population: Variation across Space and Time in Nubians Using Cranial Discrete Traits

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.     

Methods and Challenges for the Seismic Assessment of Historic Masonry Structures

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.     

Simulation of Shake Table Tests on Out-of-Plane Masonry Buildings. Part (V): Discrete Element Approach

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.     

Detecting modes in low-dimensional archaeological data

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.     

古代青铜器修复钎焊用钎剂与钎料的改性研究

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。     

银纳米薄膜试片在博物馆藏展材料评估筛选中的应用

Oddy测试法是一种最为常用的评估材料是否适合博物馆文物储藏与展示的测试方法,其缺点在于采用活性低的块状金属试片,需要28天的测试周期,同时试片表面平整度以及人为主观因素会影响目测结果的准确性.本工作制备了银纳米薄膜试片替代Oddy测试法中块状金属试片,以半径10mm玻璃圆片为基质,银薄膜厚度约为200～220nm.实验结果表明,采用银纳米薄膜试片后,腐蚀现象在14d后可充分显现并分化,延长至28d时腐蚀现象基本无大变化,有效的缩短了测试周期.同时尝试结合数码图像采集技术,有利于进一步的腐蚀现象数据化分析研究工作,从而得到更加客观准确的测试结果.