1,721,462 research outputs found
Benson, D B, 402487
No full textThis record was harvested from a previous catalogue system and will be withdrawn in 2025. Information in this record may be superseded or incomplete. Visit this record in UMA's new catalogue at: https://archives.library.unimelb.edu.au/nodes/view/371420Surname: BENSON
Given Name(s) or Initials: D B
Military Service Number or Last Known Location: 402487
Missing, Wounded and Prisoner of War Enquiry Card Index Number: 55841181915
Item: [2016.0049.03747] "Benson, D B, 402487
Design and Fabrication of Optical Fiber Sources in the Middle Infrared
No full textIn questa tesi viene svolto un accurato studio di fattibilità di diversi laser in fibra per applicazioni nel medio infrarosso tramite software fatti in casa. Vengono proposti diversi vetri drogati e schemi di pompaggio. In particolare, la tesi riporta i risultati di simulazioni riferite a: i) una sorgente ottica ottimizzata che sfrutta una configurazione MOPA (master oscillator power amplifier), con lunghezze d'onda di pompa e segnale pari a 1709 nm e 4384 nm, rispettivamente; ii) la progettazione di un efficiente schema di pompaggio per un laser in fibra Dy3+:Ga5Ge20Sb10Sb10S65 che fornisce un'emissione intorno alla lunghezza d'onda di 4400 nm, impiegando due fasci ottici di pompaggio a 2850 nm e 4092 nm; iii) l'impiego della tecnica di ottimizzazione PSO (particle swarm optimization) per massimizzare il guadagno ottico di un amplificatore in fibra, pompato in banda, basato su vetro ZBLAN drogato con disprosio; iv) la progettazione di un laser CW (continuous-wave) in fibra basato sullo stesso vetro ZBLAN drogato con disprosio; v) un modello numerico nel tempo di una fibra in vetro ZBLAN drogato con disprosio, sviluppato per progettare un laser impulsato che emette a circa 3 μm di lunghezza d'onda, utilizzando la tecnica della commutazione del guadagno. In tutti i casi, vengono presi in considerazione parametri spettroscopici misurati su campioni preliminari di vetri calcogenuro e ZBLAN per ottenere simulazioni realistiche. I vetri calcogenuri sono estremamente promettenti per applicazioni innovative a lunghezze d'onda più lunghe, ma sono necessari ulteriori sforzi tecnologici in termini di purificazione del vetro, tiraggio delle fibre e drogaggio con terre rare. D'altra parte, i vetri ZBLAN offrono la possibilità di sviluppare nuovi laser utilizzando fibre ottiche disponibili sul mercato. Per questo motivo, è stata avviata un'attività sperimentale in collaborazione con il gruppo di ricerca guidato dal Prof. Gianluca Galzerano del Dipartimento di Fisica del Politecnico di Milano per realizzare il set-up di un laser CW in fibra ZBLAN drogata con disprosio a 3 μm.In this thesis, the feasibility investigation of different fiber lasers for mid-IR applications is accurately performed via home-made computer codes. Different host glasses and pumping schemes are proposed. In particular, the thesis reports simulation results referring to: i) an optimized optical source exploiting a master oscillator power amplifier (MOPA) configuration, the MOPA pump and signal wavelengths being 1709 nm and 4384 nm, respectively; ii) the design of an efficient pumping scheme for a Dy3+:Ga5Ge20Sb10S65 fiber laser which provides an optical beam emission close to 4400 nm wavelength by employing two pump beams at 2850 nm and 4092 nm wavelengths; iii) the employment of the particle swarm optimization (PSO) technique to maximize the optical gain of an in-band pumped fiber amplifier based on a dysprosium-doped ZBLAN glass; iv) the design of a continuous-wave (CW) fiber laser based on the same dysprosium-doped ZBLAN glass; v) a time-dependent numerical model of a dysprosium-doped ZBLAN glass fiber developed in order to design a pulsed laser emitting at about 3 μm wavelength, by employing the gain switching technique. In all the cases, spectroscopic parameters measured on preliminary samples of chalcogenide and ZBLAN glasses are taken into account to fulfill realistic simulations. Chalcogenide glasses are extremely promising for innovative applications at longer wavelengths, but further technological efforts in terms of glass purification, fiber drawing and doping with rare earths are required. On the other hand, ZBLAN glasses offer the possibility to develop novel lasers by employing available-on-the-market optical fibers. For this reason, an experimental activity in collaboration with the research group led by Prof. Gianluca Galzerano of the Department of Physics of Polytechnic University of Milan has been started in order to realize the set-up of a CW dysprosium-doped ZBLAN fiber laser emitting at 3 μm
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
No full text“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
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
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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