Ottica geometrica e ondulatoria, e applicazioni astrofisiche

L’ottica è rivolta allo studio delle proprietà della luce e della sua propagazione attraverso i mezzi materiali. Le applicazioni tradizionali dell’ottica includono le lenti correttive per la vista e la formazione delle immagini nei telescopi e nei microscopi. Le applicazioni moderne comprendono l’immagazzinamento ed il recupero delle informazioni, come nei riproduttori di compact disc, nei lettori di codici a barre in uso nelle casse dei supermercati, o nella trasmissione di segnali attraverso cavi a fibre ottiche, che possono trasportare una maggior quantità di informazioni dei fili in rame. Nel primo capitolo si considereranno casi nei quali la luce viaggia in linea retta e incontra ostacoli la cui dimensione è molto maggiore della lunghezza d’onda della luce. Questo è il dominio dell’ottica geometrica, che include lo studio delle proprietà degli specchi e delle lenti. Il passaggio della luce attraverso fessure molto sottili o attorno a barriere molto strette, le cui dimensioni siano confrontabili con la lunghezza d’onda della luce (a conferma della natura ondulatoria della luce) fa parte dell’ottica fisica o anche detta ottica ondulatoria, di cui si parlerà nel secondo capitolo. Nel terzo capitolo, infine, verranno trattati due metodi che sono stati adoperati nel passato per misurare la maggior peculiarità che possiede la “particella” principe dell’ottica: la velocità della luce

The deities on the Kushano-Sasanian coins

This article deals with Kushano-Sasanian coins, aiming to interpret the images of deities used on their reverses. The topic has occasionally been discussed in numismatic studies on the Kushano-Sasanian series, and some images have also been examined in archaeological literature on Central Asia. Yet Kushano-Sasanian religious imagery has never really been the subject of specific treatment. In fact, such series provide extremely interesting evidence of the religious imagery of the Sasanian period, due to the conventions which governed typological selection, since these allowed a more varied iconographic repertoire in comparison with what we can see on the imperial issues. Contrary to previous hypotheses of the phenomenon of syncretism produced by the supposed Bactrian religious specificity, the analysis results in a picture showing a fully Zoroastrian imagery, which absorbed iconographic features of Sasanian and Kushan derivation against the background of the presence of the new Sasanian power

Richard Taylor and the Red River Campaign of 1864

Trials and Tribulations Along the Red River In recent years, historians have paid increased attention to the Red River Campaign of 1864. Books by Gary Joiner and Jeffery Prushankin, in particular, have provided thoughtful and well researched analyses of the failed Union attempt to seize ...

Irma Stern (1894-1966) : the creation of an artist's reputation in her lifetime and posthumously, 1920-2013

This dissertation examines the reception of the artist, Irma Stern, from 1920 until 2013. Irma Stern has, since her lifetime, been one of South Africa's most celebrated artists. She has received a great deal of scholarly attention, attention in the popular press and on-going recognition in the market place. Through an evaluation of press clippings, literature, archival material (photographs, the minutes of meetings and letters) and market results, this study questions how Stern has come to assume such a privileged position, why she is of such scholarly interest and how she is valued in the market. The impact of different variables on Stern's reception - including social, political and intellectual factors - is investigated. It is proposed that, initially, the artist actively promoted herself, thus playing an important role in establishing her fame. However, her reputation has been built over time and what emerges as important is that audiences have approached and interpreted Stern differently at different times. During the artist's lifetime she was admired for her perceived ability to capture the 'spirit of Africa', apparently evident in her paintings of those culturally different from her. These paintings - of black African, Indian, coloured and Arab subjects - have remained an integral aspect of the artist's reputation and they are at the centre of much of the scholarly debate on the artist in the 1990s and 2000s. Stern has provided rich material for writers at different times and of different ideological positions - from colonial to postcolonial discourse and feminist studies. Also relevant to Stern's sustained reputation is the international recognition the artist has received. Stern's links to German Expressionism and recognition from foreign scholars and institutions served to legitimate the artist to a South African audience in her lifetime and posthumously. Moreover, the market has had an impact on Stern's reputation. While she was commercially successful in her lifetime, in the early 2000s her market values exceeded those of earlier periods and surpassed those of other twentieth-century South African artists. As a result, Stern's reputation in the 2000s is linked to her high market values; this dissertation closely investigates some of the factors that have influenced this market value. In conclusion, this dissertation fills a gap in the literature because it 1) analyses the artist's market and 2) provides an in-depth investigation of the development of the artist's reputation. A study in reception, it does not add to the already plentiful appraisals of the artist's work but considers instead how this work has fared within the context of the academic, popular and commercial art world

Artificial intelligence and model checking methods for in silico clinical trials

Model-based approaches to safety and efficacy assessment of pharmacological treatments (In Silico Clinical Trials, ISCT) hold the promise to decrease time and cost for the needed experimentations, reduce the need for animal and human testing, and enable personalised medicine, where treatments tailored for each single patient can be designed before being actually administered. Research in Virtual Physiological Human (VPH) is harvesting such promise by developing quantitative mechanistic models of patient physiology and drugs. Depending on many parameters, such models define physiological differences among different individuals and different reactions to drug administrations. Value assignments to model parameters can be regarded as Virtual Patients (VPs). Thus, as in vivo clinical trials test relevant drugs against suitable candidate patients, ISCT simulate effect of relevant drugs against VPs covering possible behaviours that might occur in vivo. Having a population of VPs representative of the whole spectrum of human patient behaviours is a key enabler of ISCT. However, VPH models of practical relevance are typically too complex to be solved analytically or to be formally analysed. Thus, they are usually solved numerically within simulators. In this setting, Artificial Intelligence and Model Checking methods are typically devised. Indeed, a VP coupled together with a pharmacological treatment represents a closed-loop model where the VP plays the role of a physical subsystem and the treatment strategy plays the role of the control software. Systems with this structure are known as Cyber-Physical Systems (CPSs). Thus, simulation-based methodologies for CPSs can be employed within personalised medicine in order to compute representative VP populations and to conduct ISCT. In this thesis, we advance the state of the art of simulation-based Artificial Intelligence and Model Checking methods for ISCT in the following directions. First, we present a Statistical Model Checking (SMC) methodology based on hypothesis testing that, given a VPH model as input, computes a population of VPs which is representative (i.e., large enough to represent all relevant phenotypes, with a given degree of statistical confidence) and stratified (i.e., organised as a multi-layer hierarchy of homogeneous sub-groups). Stratification allows ISCT to adaptively focus on specific phenotypes, also supporting prioritisation of patient sub-groups in follow-up in vivo clinical trials. Second, resting on a representative VP population, we design an ISCT aiming at optimising a complex treatment for a patient digital twin, that is the virtual counterpart of that patient physiology defined by means of a set of VPs. Our ISCT employs an intelligent search driving a VPH model simulator to seek the lightest but still effective treatment for the input patient digital twin. Third, to enable interoperability among VPH models defined with different modelling and simulation environments and to increase efficiency of our ISCT, we also design an optimised simulator driver to speed-up backtracking-based search algorithms driving simulators. Finally, we evaluate the effectiveness of our presented methodologies on state-of-the-art use cases and validate our results on retrospective clinical data

Again on “Heraios” being Kujula and some related problems

The question of the identity of the issuer of the so-called “Heraios”coinage is analysed, and it is proposed that these series be ascribed to Kujula Kadphises, as already suggested by some scholars. In this regard, the circulation of these coins and the connections established by their imagery are focused upon. Some possible inferences on the original location of Kujula Kadphises are discussed in the concluding part, hypothesizing a southern context different from the northern one commonly ascribed to the founder of the Kushan dynasty

Ballistic fire barriers - Part II

With new threats endangering the safety of substations, critical infrastructure protection in substations has come to include sniper fire, ballistics and blast protection. Safe by Design approach allows that all types of design safety and performance criteria – fire, blast, impact, wind – cross over from safety to security. In this article Critical Infrastructure Protection innovations and strategy options are discussed, with a focus on ballistic fire barriers that provide both safety and security at critical facilities