1,355,676 research outputs found
Multichannel wavelength conversion of 40 Gbit/s NRZ DPSK signals in a highly nonlinear dispersion flattened lead silicate fibre
No full textWe experimentally demonstrate the wavelength conversion of three wavelength multiplexed 40 Gbit/s Differential Phase Shift Keyed (DPSK) signals in a 2.2m length of highly nonlinear, dispersion tailored W-type lead-silicate optical fibre
New optical fibre based technologies and their application in highly nonlinear systems
No full textThis thesis investigates new fibre technologies and their application in nonlinear optical systems, designed mainly for telecommunications. The thesis includes a study of two different directions in achieving a high nonlinearity in a fibre system, namely holey fibres filled with nonlinear liquids and soft glass, small core microstructured fibres. The challenges arising from the development of liquid-filled structures have made soft glass microstructured fibres the technology of choice for the realisation of highly nonlinear systems.Amongst the various soft glasses, commercially available lead-silicate glasses are identified as the material for the development of highly nonlinear fibres. Small-core, leadsilicate fibres with different designs are considered within this thesis. A solid core holey fibre design as well as two all-solid designs, a multi-ring cladding and a simpler W-index profile, are characterised. The measurements confirm the advantages of the all-solid designs over the holey structures and reveal the possibility to achieve simultaneously a high nonlinear coefficient and a novel dispersion profile in such fibres. Some of the presented fibres are employed in all-optical wavelength conversion schemes based on four-wave-mixing. Numerical simulations and experimental results are combined to study the performance of the fibres and demonstrate their use in wavelength conversion devices. In particular, a lead-silicate W-index profile fibre, showing a high nonlinear coefficient of 820W-1km-1 with a near zero dispersion profile at telecoms wavelengths, is employed to demonstrate a flat conversion gain in the whole C-band. The same fibre is then employed in FWM-based systems to demonstrate multi-channel wavelength conversion, generation of high repetition rate pulses and all-optical demultiplexing. The experiments presented in this thesis clearly reveal the potential of small-core soft-glass fibres for nonlinear applications.The use of soft glass microstructured fibres in the mid-IR is also investigated. Tellurite holey fibres with different core sizes and hole arrangements are employed in a supercontinuum generation scheme
Wavelength conversion in a short length of a solid lead-silicate fibre
No full textWe experimentally demonstrate a four-wave-mixing-based wavelength conversion scheme at 1.55 µm using a 1.1-m length of highly nonlinear, dispersion tailored W-type lead–silicate optical fibe
Applications of highly nonlinear dispersion tailored lead silicate fibres for high speed optical communications
No full textRecent advances in optical fibre technology, most notably in the area of microstructured optical fibres (MOFs), offer a host of new opportunities within future high speed communication systems. Herein we review how our recent progress on the implementation of lead silicate fibre designs, allowing both flexible dispersion control and a high effective nonlinearity, can be integrated into various all-optical signal processing devices for high speed optical communication systems. Highly nonlinear lead silicate fibres have already proven to be well suited for achieving efficient four-wave mixing (FWM) due to their high effective nonlinear coefficient, low dispersion profile and short length
Henry V and th Just War: Shakespeare, Gentili and Machiavelli
No full textThe essay reconstructs the links among Alberico Gentili's de Iure Belli (now considered the first treatise on a modern international law), Machiavelli''s Il Principe, and Shakespeare's Henry V. In doing so, it reconstructs the conflict between Elizabethan foreign policy and the calvinists
Generation of ultra-high repetition rate pulses in a highly nonlinear dispersion-tailored compound glass fibre
No full textThe generation of ultrastable optical pulses beyond 160GHz is demonstrated based on two injection-locked CW lasers through nonlinear temporal compression in a high SBS threshold highly nonlinear dispersion tailored compound glass W-type fibre
“For I love thee against my will”. From Comicality to Humorousness in “Much Ado About Nothing”
No full textIn Much Ado About Nothing, una delle sue commedie più brillanti, Shakespeare deride e aggredisce il linguaggio amoroso usato dall’aristocrazia durante il doloroso processo di civilizzazione (N. Elias) che la nascita delle corti europee esige. La “guerra d’amore” tra due dei più popolari e spiritosi personaggi delle commedie shakespeariane mette in scena la resistenza dell’aristocrazia guerriera a rinunciare a una parte del suo potere per sottomettersi all’autorità del sovrano. Affidata a due personaggi-fool, tuttavia, la critica all’obbedienza politica, travestita da un comico battibecco amoroso, assume una spumeggiante creatività linguistica che permette a Shakespeare di fare evolvere il comico in umoristica e dolorosa accettazione della disciplina di corte.In Much Ado About Nothing, one of his most brilliant comedies, Shakespeare mocks and attacks the amorous language used by the aristocracy during the painful process of civilization (N. Elias) that the emergence of European courts demanded. The “war of love” engaged by two among the most popular and witty Shakespearean characters stages the resistance of a warlike aristocracy to give up part of its own power and to surrender to the authority of the sovereign. Given to two character-fools, however, the critique of political obedience is articulated in the form of a comical as well as sparkling spat that allows Shakespeare to elevate the comedy to humoristic and painful acknowledgement of court discipline.  
Choosing the duration of continuous glucose monitoring for reliable assessment of time in range: A new analytical approach to overcome the limitations of correlation-based methods
No full textAims: Reliable estimation of the time spent in different glycaemic ranges (time-in-ranges) requires sufficiently long continuous glucose monitoring. In a 2019 paper (Battelino et al., Clinical targets for continuous glucose monitoring data interpretation: recommendations from the international consensus on time in range. Diabetes Care. 2019;42:1593-1603), an international panel of experts suggested using a correlation-based approach to obtain the minimum number of days for reliable time-in-ranges estimates. More recently (in Camerlingo et al., Design of clinical trials to assess diabetes treatment: minimum duration of continuous glucose monitoring data to estimate time-in-ranges with the desired precision. Diabetes Obes Metab. 2021;23:2446-2454) we presented a mathematical equation linking the number of monitoring days to the uncertainty around time-in-ranges estimates. In this work, we compare these two approaches, mainly focusing on time spent in (70-180) mg/dL range (TIR). Methods: The first 100 and 150 days of data were extracted from study A (148 subjects, ~180 days), and the first 100, 150, 200, 250 and 300 days of data from study B (45 subjects, ~365 days). For each of these data windows, the minimum monitoring duration was computed using correlation-based and equation-based approaches. The suggestions were compared for the windows of different durations extracted from the same study, and for the windows of equal duration extracted from different studies. Results: When changing the dataset duration, the correlation-based approach produces inconsistent results, ranging from 23 to 64 days, for TIR. The equation-based approach was found to be robust versus this issue, as it is affected only by the characteristics of the population being monitored. Indeed, to grant a confidence interval of 5% around TIR, it suggests 18 days for windows from study A, and 17 days for windows from study B. Similar considerations hold for other time-in-ranges. Conclusions: The equation-based approach offers advantages for the design of clinical trials having time-in-ranges as final end points, with focus on trial duration
Il sogno di Eva. Sesso e destino in Paradise Lost.
No full textL'articolo analizza il rapporto tra il sogno di Eva nel Libro V del Paradise Lost e la scena della tentazione e della caduta del Libro IX. La tesi dell'articolo è che il sogno sensuale di Eva indotto dal Serpente prefigura le motivazioni fondamentalmente sessuali ed erotiche della caduta, aprendo così una inaspettata possibilità che Milton concordi con l'interpretazione agostiniana del peccato originale come impossibilità degli uomini di controllare liberamente la propria sessualità
Discorso sul libero pensiero di Mr Collins messo in inglese semplice, in un Compendio, a uso dei poveri.
No full texttraduzione libello di Swift contro il libero pensiero di Anthony Collin
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