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71.
Few anthropologists today would consider using the term 'tribe' as an analytical category, yet it has become a focal point for military commanders and other leaders prosecuting the wars in Iraq and Afghanistan. Specifically, US-led occupation forces in both countries have begun pursuing 'tribal' strategies in which they have attempted to forge alliances with 'sheiks' and local power brokers. This article examines the reasons for the rapid rise of 'tribal' discourses, the role of social scientists in their propagation and the possible consequences for Iraqis and Afghans. It concludes by comparing these processes to ethnographically-informed pacification efforts initiated in the late 1800s and early 1900s by the European powers, and by suggesting that anthropologists can potentially play a critical role by challenging persistent, damaging assumptions.  相似文献   
72.
73.
This article examines the reported use of ‘big data’ analysis by Cambridge Analytica in support of Donald Trump's presidential campaign. It investigates the transformations enveloping the overlapping worlds of politics, technology and social science. In particular, it critically reviews new developments in the field of psychometrics that have enabled researchers to harvest vast quantities of data by accessing social media platforms such as Facebook. The article also assesses claims that predictive analytics and ‘psychographics’ led to Trump's unexpected victory. The article concludes with a broader discussion about the state of political discourse in an era of digital communication.  相似文献   
74.
ABSTRACT.  The RAS method is used to update or regionalize a single matrix such that it conforms to new row and column totals. This paper presents a correction of the RAS method (CRAS) that uses cell variation distributions calculated from multiple matrices of different periods or different regions. After the solution of the regular RAS, an additional optimization problem is solved that produces the most likely cell-corrections to the regular RAS solution. To test the behavior of CRAS, several simulations with a time series of input–output tables for The Netherlands for 1968–1986 are made. They show that—in situations of structural change—applying CRAS improves the regular RAS estimate. The method will also be applicable to traffic, trade, and migration matrices.  相似文献   
75.
In Archaeology, geophysical methods had been applied usually in a qualitative form, limited only to the use of filters that enhance the data display. The main objective in this work is the implementation of a modelling technique that allows us to reconstruct the geometry of buried bodies and the determination of their depths. This is done by means of the estimation of the magnetic moments of archaeological objects using a three-dimensional mesh of individual magnetic dipoles using the least squares method and the singular value decomposition of a weighted matrix to solve the linear problem. The distribution and shape of the underlying archaeological remains can be inferred. This methodology was applied to an archaeological site called Los Teteles de Ocotitla, in the state of Tlaxcala, Mexico. A high-resolution magnetic prospection was carried out in three selected areas (terraces). The most important total field anomalies found on each area were inverted, obtaining results that were corroborated by archaeological excavations. This investigation demonstrates the potential of quantitative geophysical methods for the characterization of archaeological structures, in extension and in depth.  相似文献   
76.
The identification of chemical activity residues on archaeological surfaces requires the analysis of large numbers of samples, which can be costly and time consuming. Researchers wishing to apply sediment chemistry often are confronted with a dilemma of which technique to use and how to accommodate sediment chemistry into their budget. We propose an approach to the identification of chemical activity residues in which semiquantitative spot tests, which are cheap, quick, and easy to apply, are employed as an initial phase of analysis in order to leverage the results of more time-consuming and costly instrumental techniques. Three examples that pair spot tests with gas chromatography-mass spectroscopy and inductively coupled plasma-optical emission spectrometry analysis show that spot tests successfully identify areas of interest. This approach can save both time and research funds.  相似文献   
77.
Barnacles of the species Pollicipes pollicipes are crustaceans that nowadays live on wave-beaten rocky substrates in the intertidal and low-shore zones on the coasts of Atlantic Europe and North Africa. At the present time, the exploitation of this species is profitable, especially in northern Spain where this sea-food is highly valued, as well as expensive. However, the gathering of this resource, which is carried out manually by the percebeiros or “goose barnacle fishers” entails great risks.  相似文献   
78.
ABSTRACT

In this study, industrial single-story RC precast buildings are investigated. Twenty-four case studies have been considered, in which the column height, the beam spans and the seismic hazard level are varied. The seismic design of the selected case studies is performed according to the Italian building code and additional technical documentation. Three-dimensional nonlinear models are defined to perform static and dynamic analyses for the seismic assessment of the selected case studies. Demand/capacity ratios in terms of the selected engineering demand parameters are computed for ten increasing values of the seismic input return period.  相似文献   
79.
The article presents the results of an experimental and numerical investigation on Azzone Visconti bridge, a 14th century arch bridge in Lecco (northern Italy). Starting from the historical data and from an extensive mechanical characterization of both the soil constituting the riverbed and of the masonry constituting the piers, the aim of the study is to investigate the bearing capacity of the bridge. A testing loading scheme defined according to the current Italian Code is adopted to check the structural behavior. A simplified finite element structural model was conceived and calibrated as a control tool to safely perform the experimental tests. Post-test nonlinear finite element analyses have allowed the prediction of the bridge bearing capacity and the definition of the bridge class according to the Italian regulations.  相似文献   
80.
Theories and data do not always fit and sometimes are sources of conflicts among scientists. This is the case of a morphological structure, the perineuronal net, which was denied on the basis of an ideological conflict between two giants of neurosciences: Camillo Golgi and Santiago Ramón y Cajal. The perineuronal net is a reticular structure enveloping many neurons. Originally reported by Golgi in 1893 and 1898 and confirmed by several authors before the turn of the century, the perineuronal net was used by Golgi to support the reticular theory of the organization of the nervous system. Ramón y Cajal, the paladin of the neuronal theory who had also observed this anatomical structure, denied its existence suggesting that it was a fixation artifact. After Cajal's statements, only a few Italian scientists continued to work in this field, and after the 1930s the perineuronal net was forgotten. Only the recent advances in histochemical and immunocytochemical technology confirmed the existence of this structure opening new fields in functional neuroanatomy and neuropathology.  相似文献   
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