121,774 research outputs found
Le false comunicazioni sociali: problemi antichi e nuovi
No full textIl lavoro considera il novellato sistema di incriminazione delle false comunicazioni sociali, quale configurato con la legge n. 69 del 2015, evidenziando come sia caratterizzato da un elevato tasso di indeterminatezza, essendo molteplici gli elementi rimessi alla valutazione del giudice, in assenza di criteri definiti in grado di assicurare una prevedibile ed uniforme interpretazione e applicazione, come la problematica delle valutazioni ha subito dimostrato. In questo quadro, viene prospettata, come unica via percorribile, quella di una lettura rigorosa che assegni al dato normativo il significato più ristretto possibile, anche alla luce di una più precisa definizione dell’oggetto della tutela, come suggerisce il contesto dei reati societari, nel quale le false comunicazioni sono, pur sempre, inserite
Preliminary demonstration of a persistent Josephson phase-slip memory cell with topological protection
No full textSuperconducting computing promises enhanced computational power in both classical and quantum approaches. Yet, scalable and fast superconducting memories are not implemented. Here, we propose a fully superconducting memory cell based on the hysteretic phase-slip transition existing in long aluminum nanowire Josephson junctions. Embraced by a superconducting ring, the memory cell codifies the logic state in the direction of the circulating persistent current, as commonly defined in flux-based superconducting memories. But, unlike the latter, the hysteresis here is a consequence of the phase-slip occurring in the long weak link and associated to the topological transition of its superconducting gap. This disentangles our memory scheme from the large-inductance constraint, thus enabling its miniaturization. Moreover, the strong activation energy for phase-slip nucleation provides a robust topological protection against stochastic phase-slips and magnetic-flux noise. These properties make the Josephson phase-slip memory a promising solution for advanced superconducting classical logic architectures or flux qubits
Thermal superconducting quantum interference proximity transistor
No full textSuperconductors are excellent thermal insulators at low temperatures owing to the presence of an energy gap in their density of states1. Through the so-called proximity effect2, superconductors can influence the density of states of nearby metallic or superconducting wires. In this way, the local density of states of a wire can be tuned by controlling the phase bias (φ) imposed across it3. Here we demonstrate a thermal superconducting quantum interference proximity transistor (T-SQUIPT) that enables the phase control of heat currents by exploiting the superconducting proximity effect. Our T-SQUIPT device comprises a quasi-one-dimensional aluminium nanowire forming the weak link embedded in a superconducting ring4,5. Controlling the phase bias by changing the magnetic flux through the ring shows temperature modulations of up to 16 mK, yielding a temperature-to-flux transfer function that reaches approximately 60 mK Φ0–1. We also demonstrate a hysteretic dependence of the local density of states of T-SQUIPTs on the applied magnetic field due to phase-slip transitions. This allows the T-SQUIPT device to operate as a phase-tunable thermal memory6,7, where the information is encoded in the temperature of the metallic mesoscopic island
Fully superconducting josephson bolometers for gigahertz astronomy
No full textThe origin and the evolution of the universe are concealed in the evanescent diffuse extragalactic background radiation (DEBRA). To reveal these signals, the development of innovative ultra-sensitive bolometers operating in the gigahertz band is required. Here, we review the design and experimental realization of two bias-current-tunable sensors based on one dimensional fully superconducting Josephson junctions: the nanoscale transition edge sensor (nano-TES) and the Josephson escape sensor (JES). In particular, we cover the theoretical basis of the sensors operation, the device fabrication, their experimental electronic and thermal characterization and the deduced detection performance. Indeed, the nano-TES promises a state-of-the-art noise equivalent power (NEP) of about 5 × 10−20 W/√Hz, while the JES active region is expected to show an unprecedented NEP of the order of 10−25 W/√Hz. Therefore, the nano-TES and JES are strong candidates to push radio astronomy to the next level
Vanadium gate-controlled Josephson half-wave nanorectifier
No full textRecently, the possibility to tune the critical current of conventional metallic superconductors via electrostatic gating was shown in wires, Josephson weak-links, and superconductor-normal metal-superconductor junctions. Here, we exploit such a technique to demonstrate a gate-controlled vanadium-based Dayem nano-bridge operated as a half-wave rectifier at 3 K. Our devices exploit the gate-driven modulation of the critical current of the Josephson junction and the resulting steep variation of its normal-state resistance, to convert an AC signal applied to the gate electrode into a DC one across the junction. All-metallic superconducting gated rectifiers could provide the enabling technology to realize tunable photon detectors and diodes useful for superconducting electronics circuitry
Hypersensitive tunable josephson escape sensor for gigahertz astronomy
No full textSingle-photon detectors and bolometers represent the bridge between different topics in science, such as quantum computation, astronomy, particle physics, and biology. Nowadays, superconducting bolometers and calorimeters are the most-sensitive detectors in the terahertz and subterahertz bands. Here, we propose and demonstrate a Josephson escape sensor (JES) that could find natural application in astrophysics. The JES is composed of a fully superconducting one-dimensional Josephson junction, whose resistance-versus-temperature characteristics can be precisely controlled by a bias current. Therefore, differently from traditional superconducting detectors, the JES sensitivity and working temperature can be in situ simply and finely tuned depending on the application requirements. A JES bolometer is expected to show an intrinsic thermal-fluctuation-noise noise-equivalent power on the order of 10-25W/Hz1/2, while a JES calorimeter could provide a frequency resolution of about 2 GHz, as deduced from the experimental data. In addition, the sensor can operate at the critical temperature (i.e., working as a conventional transition-edge sensor), with a noise-equivalent power of approximately 6×10-20W/Hz1/2 and a frequency resolution of approximately 100 GHz
A Multi-Language Comparison of Influences on Author Verification using Character N-Grams
No full textWe create a new multi-language corpus for author verification based on Wikipedia talkpages, and evaluate the influence that differences in topic and time have on character n-gram author profiles. Topic alignment between two texts is found to increase author verification precision, and an authors writing style is found to change over time, but not more significantly after 3 years than after 1 year.Information ArchitectureWISElectrical Engineering, Mathematics and Computer Scienc
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe 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
The vanishing author in computer-generated works: a critical analysis of recent Australian case law
No full textAbstract
The use of software is ubiquitous in the creation of many copyright works, yet the requirement in copyright law that every work have a human author who engages in independent intellectual effort means that its use may prevent copyright subsistence. Several recent Australian cases have refocused attention on authorship as an essential criterion of copyright subsistence, and these cases suggest that much computer-produced output may be authorless and thus lack copyright protection. This article, the first in a two-part series, analyses how each case deals with the question of authorship of computer-produced works and why the use of software diminishes copyright protection for a significant number of computer-generated works. The article critiques the application of conventional notions of human authorship developed in the pre-computer age to modern productions and suggests alternative approaches to authorship that satisfy both the major objectives of copyright policy and the need to adapt to the computer age. The article argues that, without a broader judicial approach to authorship of computer-generated works, Parliament must remedy the lacuna in protection for these ‘authorless’ works. Possible solutions for reform are suggested. In a forthcoming article, the author comprehensively examines those reform proposals
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