1,721,150 research outputs found
On the transmission of waves at discrete frequencies from the solar wind to the magnetosphere and ground: A case study
No full textWe analyze a case event in which several fluctuations at discrete frequencies (f ≈ 1.3-1.5, 3.3-3.6, 4.4-4.6, and 5.9-6.2 mHz; i.e., close to the "CMS" frequencies) were observed in the magnetosphere, after the impact of a sharp shock wave that, in the interplanetary medium, was followed by intense fluctuations in the solar wind parameters. The comparison between interplanetary, geosynchronous, and ground-based observations revealed that following the Sudden Impulse, magnetospheric modes at the same discrete frequencies were detected at geostationary orbit by spacecraft located in the morning and the dawn sector, and, ubiquitously, at ground-based stations: all of them revealed a one-to-one correspondence with those ultimately identified in the high-velocity stream following the shock wave. It reveals that the occurrence of such global modes is directly related to the transmission of external fluctuations and the observed geomagnetic fluctuations might be interpreted as the ground magnetic response to magnetospheric compressional modes forced by oscillations of the solar wind pressure at the same frequencies. By contrast, we did not find any evidence for magnetospheric oscillations possibly related to other mechanisms such as the velocity shear, the impact of the shock wave itself, etc. Key Points Inherent SW waves at discrete frequencies trasmitted to the magnetosphere No evidence for waves related to KHI or to shock waves impact One to one correspondence between frequencies of ground, magnetosphere, and SW waves
VLSI Design and FPGA Implementation of an NTT Hardware Accelerator for Homomorphic SEAL-Embedded Library
No full textHomomorphic Encryption (HE) allows performing specific algebraic computations on encrypted data without the need for decryption. For this reason, HE is emerging as a strong privacy-preserving solution in cloud computing environments since it allows to keep data secure even in the case the cloud server is not trusted. HE libraries such as Microsoft SEAL have been recently released; however, such libraries are not specifically designed for resource-constrained platforms and they are often expensive in terms of computational resources and memory consumption, which limits their usage in edge devices. This limitation is contained by the SEAL-Embedded library, the first C-based HE library specifically designed for embedded platforms. In this article, we propose a hardware accelerator specifically designed for the SEAL-Embedded library and its implementation of the CKKS scheme: the proposed hardware presents a configurable Number Theoretic Transform (NTT) unit for all the polynomial degrees available on the SEAL-Embedded, a memory architecture able to reduce the I/O latency and a dedicated module for the generation of roots of unity. A complete system that includes a 32-bit RISC-V (RI5CY) processor has been implemented on a Xilinx ZCU106 FPGA board to test the functionality of the hardware accelerator and to measure performance improvements. The results showed a speed-up of around x1000 with the hardware acceleration respect to the pure software implementation of the SEAL-Embedded library for the symmetric encryption function
A cost-effectiveness analysis of different therapies in patients with chronic hepatitis B in Italy
No full text
Un mistero risolto: il “Maestro della cappella Marciac” a Trinità dei Monti, alias Guillaume Bonoyseau “Gallico”
No full textGoing Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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