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71.
72.
Abstract

The historian Carlo Ginzburg is renowned for his critique of modern, scientific reason and his articulation of an alternative form of knowledge which he labels ‘conjectural’. This form of knowledge, supposedly more attuned to the historian’s interest in the singular and specific fragment, as opposed to the abstract and universal concept, is so rooted in the practices of the prehistoric hunter that Ginzburg sometimes describes it as a ‘venatic’ form of deduction, binding ‘the human animal closely to other animal species’. In this essay, I explore the ramifications of this alternative form of knowledge, attending especially to its relationship to the modernist theme of ‘primitivism’. I do so by juxtaposing Ginzburg’s critical appraisal of Arthur Conan Doyle’s most famous literary invention, Sherlock Holmes, and Rudolph Fisher’s own literary invention, John Archer, the physician who sometimes aids criminal investigations in African American Harlem. I argue that the differences between Archer and Holmes draw attention to some troubling implications of Ginzburg’s historiographical argument. Folding this analysis on itself, however, I also suggest that what might be at stake, when Ginzburg insists so troublingly on the importance of the singular, venatic trace, is the evocation of Walter Benjamin’s understanding of the historical ‘event’.  相似文献   
73.
Most current methods for automatic text categorization are based on supervised learning techniques and, therefore, they face the problem of requiring a great number of training instances to construct an accurate classifier. In order to tackle this problem, this paper proposes a new semi-supervised method for text categorization, which considers the automatic extraction of unlabeled examples from the Web and the application of an enriched self-training approach for the construction of the classifier. This method, even though language independent, is more pertinent for scenarios where large sets of labeled resources do not exist. That, for instance, could be the case of several application domains in different non-English languages such as Spanish. The experimental evaluation of the method was carried out in three different tasks and in two different languages. The achieved results demonstrate the applicability and usefulness of the proposed method.  相似文献   
74.
Through an analysis of 497 foreign researchers in Italy and Portugal we verify the impact of home linkages on return mobility choices and scientific productivity. We consider the presence of several different types of linkages of the researchers working abroad with their country of origin and control for the most relevant contextual factors (age, research area, position in the host country, etc.). The probability of return to their home country and scientific productivity in the host country are both higher for researchers that maintain home linkages. We conclude that the presence of home linkages directly benefits both countries in addition to the indirect benefit of expanding the scientific networks. Policy implications and suggestions for further research are discussed.  相似文献   
75.
This work is focused on the petro-archeometric characterization of the fine pottery production of the archaeological site of Gela (Sicily). Thirty-five samples coming from three Archaic and Hellenistic kilns and five coming from an Hellenistic house, were investigated by means of optical microscopy, XRD and XRF analysis. With the exception of some ceramics which are undoubtedly imported, all the samples have similar petrographic features, but on the basis of chemical composition, we can distinguish two different groups. The presence of two local productions is confirmed by the comparison with locally outcropping sediments and with archaic and modern bricks of sure Geloan production. This result is particularly significant for the definition of reference groups of this wealthy polis that played an important trading role in the Mediterranean area.  相似文献   
76.
In the present work, an analytical characterization of painted plaster samples coming from ancient buildings dated back to 2nd cent. B.C., located in Licata (Sicily, Southern Italy), has been carried out. The investigation has been performed through different spectroscopic techniques: X-ray fluorescence (XRF) using an handheld energy-dispersive XRF analyzer, scanning electron microscopy equipped with an Energy Dispersive Spectrometry microanalysis detector (SEM-EDS) and Fourier transform infrared absorbance spectroscopy (FT-IR). The main goal is to identify the plaster and pigments material. In particular, the XRF investigation of surfaces is the first step for a preliminary elemental characterization. Then, through SEM-EDS measurements, a quantitative analysis of the chemical composition of the plaster and the pigmenting agents along with eventual components related to deterioration processes has been obtained. Finally, FT-IR absorbance spectra have proven to be a useful tool to investigate the molecular nature of the used materials.  相似文献   
77.
Using data from the five waves of the Italian Longitudinal Household Survey, this paper examines the dynamics of Italian higher education in the twentieth century. The main goals are to study changes in participation in higher education (enrolment, transition, and graduation rates), in performance (drop out and delayed graduation rates, average delay duration), and how these have changed in different social classes. The main results are as follows. Enrolment growth has not been followed by a proportional increase in graduation rates. The drop out rate, the number of delayed graduations and the average delay duration were already high before the 1969 reform, and subsequently increased over time. Delayed graduations increased among students from both upper-middle and lower-middle classes, whereas the drop out rate rose only among the latter, and stayed steady for the former. As a whole, absolute inequalities persisted over time, with any slight reduction that took place resulting from declining performance of the upper classes, and not from an improvement of the lower classes.
Paolo TrivellatoEmail:
  相似文献   
78.
This paper proposes a novel query expansion method to improve accuracy of text retrieval systems. Our method makes use of a minimal relevance feedback to expand the initial query with a structured representation composed of weighted pairs of words. Such a structure is obtained from the relevance feedback through a method for pairs of words selection based on the Probabilistic Topic Model. We compared our method with other baseline query expansion schemes and methods. Evaluations performed on TREC-8 demonstrated the effectiveness of the proposed method with respect to the baseline.  相似文献   
79.
A general procedure is outlined for obtaining single or coupled transmission line models to represent the propagation of surface wave modes in conductively unshielded dielectric waveguides. The procedure uses a homogeneous electrically or magnetically walled waveguide having the same dimensions as the dielectric of the surface waveguide, to produce a set of orthogonal eigenfunctions. These eigenfunctions are projected upon Maxwell's equations resulting in a system of transmission lines coupled together through a wave immittance, which represents the ratio of a longitudinal and a transverse field component at the dielectric-air interface. Examples are given for various modes of the dielectric slab and the dielectric rod, in particular the HE1n modes for the latter. The transmission line models derived for these examples consist of a single trasmission line found directly by projection or reduced from a coupled transmission line model by port elimination, or of two transmission lines coupled together. All circuit models derived preserve the basic properties of surface waves (e.g. no solution below cut-off), and any of the single line models can be solved to give explicit approximate algebraic formulae for the propagation constant as a function of frequency. Numerical results show that the dispersion curves calculated from the models versus exact values are generally excellent over the entire frequency spectrum.  相似文献   
80.
Dynamic sitting, such as fidgeting and desk work, might be associated with health, but remains difficult to identify out of accelerometry data. We examined, in a laboratory study, whether dynamic sitting can be identified out of triaxial activity counts. Among 18 participants (56% men, 27.3 ± 6.5 years), up to 236 counts per minute were recorded in the anteroposterior and mediolateral axes during dynamic sitting using a hip-worn accelerometer. Subsequently, we examined in 621 participants (38% men, 80.0 ± 4.7 years) from the AGES-Reykjavik Study whether dynamic sitting was associated with cardio-metabolic health. Compared to participants who recorded the fewest dynamic sitting minutes (Q1), those with more dynamic sitting minutes had a lower BMI (Q2 = ?1.39 (95%CI = ?2.33;–0.46); Q3 = ?1.87 (?2.82;–0.92); Q4 = ?3.38 (?4.32;–2.45)), a smaller waist circumference (Q2 = ?2.95 (?5.44;–0.46); Q3 = ?3.47 (?6.01;–0.93); Q4 = ?8.21 (?10.72;–5.71)), and a lower odds for the metabolic syndrome (Q2 = 0.74 [0.45;1.20] Q3 = 0.58 [0.36;0.95]; Q4 = 0.36 [0.22;0.59]). Our findings suggest that dynamic sitting might be identified using accelerometry and that this behaviour was associated with health. This might be important given the large amounts of time people spend sitting. Future studies with a focus on validation, causation and physiological pathways are needed to further examine the possible relevance of dynamic sitting.  相似文献   
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