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121.
In north-western Patagonia, obsidian was used during the entire Holocene, and its importance increased with time. Recent fieldwork discovered a new obsidian source located in the Río Grande, which was called ‘Coche Quemado' (CQ). The results indicate that the CQ source has a different geochemical signal than all other sources in the region. Its use is spatially restricted to piedmont and, to a lesser extent, the plains. Chronologically, CQ was exploited in the middle and late Holocene, and its use accounts for a range of spatial distribution between 150 and 200 km.  相似文献   
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In this paper, we describe and reflect upon our journey through Indigenous online mapping in Canada. This journey has been planned according to an academic goal: assessing the potential of online cartography for decolonial purposes. To reach this goal, we have followed methodological directions provided by Indigenous scholar Linda Tuhiwai Smith to review 18 Indigenous web-mapping sites across Canada. Supported by a series of ten interviews, this content analysis enabled us to sketch some of the contours of contemporary Indigenous cartography. On one hand, Indigenous communities largely control the data that are shared on these websites. They also partially control the way these data are represented through the mobilization of digital storytelling technologies that are better aligned with Indigenous ways of envisioning relationships to places than conventional maps. On the other hand, they do not have much control over the technological aspects of these projects, for which they remain heavily dependent on non-Indigenous partners. Throughout this journey, we noticed that women's voices remained marginal in most of these mapping projects, but we also identified evidence supporting the idea that these voices are starting to play a vital role in the on-going effort of decolonizing mapping processes.  相似文献   
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Brittany Meché 《对极》2020,52(2):475-495
September 15, 2013, marked the 50th anniversary of the 16th Street Baptist Church bombing in Birmingham, Alabama, USA. The bombing remains one of the most infamous events in the history of white supremacist violence in the United States. While conventional accounts of the event and its aftermath often consider the legal restructuring of the US state following the passage of subsequent Civil Rights legislation, little has been written about the transnational significance of Birmingham in shaping the character of US power abroad. This article argues that memorialisation and cultural architecture of Birmingham represent a significant crucible forging a particular style of liberal empire. Tracing a cultural genealogy of Birmingham through the writings of former Secretary of State and National Security Advisor Condoleezza Rice and famed scholar-activist Angela Davis, I demonstrate how Birmingham, as a site of historic black struggle, has been remembered alongside the place-making of empire.  相似文献   
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ABSTRACT

Morphometric analysis offers an alternative or augmentation to traditional archaeobotanical methods to address differences within and between plant species and their remains, refining and enhancing taxonomic resolution. Morphometrics, the measurement of size and shape, and the multivariate statistical analysis of generated quantitative variables, have long played a major role in biological research, including plant taxonomy and systematics, although its application in archaeobotany is relatively recent. Over the last few decades, there has been an increasing interest in the use of morphometrics for analysing a varied range of archaeological plant materials (mainly seeds, pollen, phytoliths, and starch grains). In particular, morphometrics have contributed to the study of the domestication and spread of many cereals world-wide, as well as that of other taxa including legumes, underground storage organs (USO), and fruits (such as olives, grapes, and dates). This paper reviews current methodologies, recent applications, and advances in the use of morphometrics in archaeobotanical research, discusses its role in exploring major research questions, and suggests possible future directions for its use.  相似文献   
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ABSTRACT

The preservation of the architectural heritage is characterized by the intervention of different technicians, who may disagree on decision-making criteria. In recent years, the H-BIM methodology has emerged to manage these buildings, although the multidisciplinary technical personnel make the decision-taking something of a challenge. In this regard, artificial intelligence may be an opportunity to establish automatic responses, thus optimizing the process. This article proposes a methodology to implement models of classification using the J48 algorithm in a H-BIM model. The case study was focused on a tiles panel from a building which belongs to the Real Alcazar of Seville. First, a model of classification was developed to estimate the degree of intervention with an adequate degree of adjustment. Then, the model was implemented in the H-BIM software by programming using GDL. This methodology automates the decision-making and reduces times of assessments, visualizing and managing the information in the H-BIM model.  相似文献   
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In the area of cultural heritage, tourists’ experiences emphasise not only the moment and its personal nature but also socio-cultural traits. These experiences when expressed (social communications) are an important gateway to knowledge about tourists’ sense-making processes. This paper reports on the mediation between tourists and heritage sites via comments on a digital platform (TripAdvisor) about two Spanish tourist destinations with opposing characteristics and four heritage sites, which are analysed. The methodology used seeks to transcend the individual and anecdotal aspects of tourists’ comments. Indeed, the results obtained show the relevance of the humanisation and the discursive weight of heritage contexts in emotional/personal stories. Tendencies observed in non-regulated contexts confirm the role of a complex negotiation at cultural heritage sites and highlight the need to explore possible exchanges of sense in tourists’ encounters with such sites.  相似文献   
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A simplified model useful for assessing economic losses due to moderate seismicity events in urban areas has been developed by studying the behavior of buildings before yielding their structural system, allowing for nonuniform stiffness along their height. In particular, buildings are modeled as cantilever shear beams with uniform mass and parabolic reduction of lateral stiffness. This particular stiffness distribution is relevant, as it could be expected to occur in buildings where earthquake action is a critical structural design criterion. The equation of motion governing the dynamic behavior of the proposed model is solved analytically, finding mode shapes in terms of first and second zero-order Legendre functions. The solution is verified by comparing it with results obtained from fine mesh finite element models. The effect of reducing the lateral stiffness is then studied in the first five modes of vibration. Results include modal periods, mode shapes, modal participation factors, and derivatives of mode shapes. In general, it is found that effects of reduction of lateral stiffness in mode shapes are moderate when the lateral stiffness in the free end is smaller than about seventy percent of the lateral stiffness at the fixed end, but become significant for larger reductions. Effects are particularly important for the derivative of the mode shapes, which could play a significant role in estimating interstory drift demands in buildings. Model usefulness is showcased by analyzing a test case where both acceleration and drift demands are assessed by considering uniform beams and beams with parabolic stiffness variation, finding notable improvements by considering the latter.  相似文献   
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