The history, practice and aesthetic of the soft focus lens in photography is elucidated and developed from its earliest statements of need to the current time with a particular emphasis on its role in the development of the Pictorialist movement. Using William Crawford's concept of photographic 'syntax', the use of the soft focus lens is explored as an example of how technology shapes style. A detailed study of the soft focus lenses from the earliest forms to the present is presented, enumerating the core properties of pinhole, early experimental and commercial soft focus lenses. This was researched via published texts in period journals, advertising, private correspondence, interviews, and the lenses themselves. The author conducted a wide range of in-studio experiments with both period and contemporary soft focus lenses to evaluate their character and distinct features, as well as to validate source material. Nodal points of this history and development are explored in the critical debate between the diffuse and sharp photographic image, beginning with the competition between the calotype and daguerreotype. The role of George Davison's The Old Farmstead is presented as well as the invention of the first modern soft focus lens, the Dallmeyer-Bergheim, and its function in the development of the popular Pictorialist lens, the Pinkham & Smith Semi-Achromatic. The trajectory of the soft focus lens is plotted against the Pictorialist movement, noting the correlation betwixt them, and the modern renaissance of soft focus lenses and the diffuse aesthetic. This thesis presents a unique history of photography modeled around the determining character of technology and the interdependency of syntax, style and art.

Polarization behaviours of copper diffused p-type GaAs was studied in 1. 0M NaCl and 1. 0M NaNO₃ by means of pitting scan and linear sweep potentiodynamic polarization techniques. The thermodynamic potential-pH diagram of the GaAs-H₂O system was constructed. The observed electrode behaviours of GaAs were compared and correlated to the potential-pH diagram. Freely corroding potential, passivation behaviour and pitting potential were examined as a function of a number of factors. These included the effects of different annealing and polishing pretreatments, the bulk solution pH and polarization methods. The corrosion potential (Ecorr) , pitting potential (Epit) and passivation behaviour were affected by the different pretreatments which changed the surface condition of GaAs. For mechanically polished samples, pitting corrosion was found in pH 7.0 solution only. The Ecorr and Eplt were independent of NO₃⁻ and Cl⁻ at pH 7.0. Initial polarization behaviour of p-GaAs at pH 2.0 and 12.0 followed the Tafel Law for semiconductors quite well. There was a reasonable correlation between the experimental observations and the potential-pH diagram of GaAs-H₂O system. SEM images of polarized samples showed that pits formed in NaCl and NaNO₃ had a different shape, being more elongated in NaCl. However, the walls of all pits appeared to be composed of {111} planes. In general, the pit distribution appeared to be similar to the dislocation distribution. A model of pitting corrosion of GaAs was proposed based on strain induced breakdown of the oxide film, localized changes in solution chemistry and the structure of the compound semiconductor. / Applied Science, Faculty of / Materials Engineering, Department of / Graduate

International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada / A 10- or 20-Watt, L- or S-band transmitter commonly consumes the majority of the available DC power on a telemetry pack -- often more than all the remaining components combined. A new family of transistors allows a substantial increase in DC to RF efficiency without the use of complex and costly switching regulators. With ever increasing data rates requiring more RF bandwidth (and correspondingly lower receiver sensitivities), transmitters using these transistors offer twice the RF power at little or no increase in DC current. Alternately, in other situations such as observation balloons, the same RF power can be achieved with approximately 40% less current resulting in significantly longer mission life. This paper describes the method for achieving higher efficiency transmitters using new LDMOSFETs.

This dissertation builds on the common notion that Beethoven's music sounds inward by grounding this impression analytically. The chapters frame Beethoven's music in terms of inward, outward, and liminal spaces. Inward spaces are slow, lyrical, formally enclosed, and harmonically distant, and they often appear under the aura of what I call a "modulating trill" or a "diffused theme." Drawing on Schmalfeldt's references to inwardness, I describe outward spaces as inward moments that "radiate outward" and note that these restore tonal stability, lost thematic material, and bass notes that had once disappeared. Finally, liminal spaces are passages that quickly juxtapose inward and outward moments, and thus they seem to exist at the cusp between these two spaces. I examine how these passages evolve throughout entire pieces, typically withdrawing deeper within.

Entanglement is the hallmark of quantum mechanics. Quantum entanglement -- putting two or more identical particles into a non-factorable state -- has been leveraged for applications ranging from quantum computation and encryption to high-precision metrology. Entanglement is a practical engineering resource and a tool for sidestepping certain limitations of classical measurement and communication. Engineered nonlinear optical waveguides are an enabling technology for generating entangled photon pairs and manipulating the state of single photons. This dissertation reports on: i) frequency conversion of single photons from the mid-infrared to 843nm as a tool for incorporating quantum memories in quantum networks, ii) the design, fabrication, and test of a prototype broadband source of polarization and frequency entangled photons; and iii) a roadmap for further investigations of this source, including applications in quantum interferometry and high-precision optical metrology. The devices presented herein are quasi-phase-matched lithium niobate waveguides. Lithium niobate is a second-order nonlinear optical material and can mediate optical energy conversion to different wavelengths. This nonlinear effect is the basis of both quantum frequency conversion and entangled photon generation, and is enhanced by i) confining light in waveguides to increase conversion efficiency, and ii) quasi-phase matching, a technique for engineering the second-order nonlinear response by locally altering the direction of a material's polarization vector. Waveguides are formed by diffusing titanium into a lithium niobate wafer. Quasi-phase matching is achieved by electric field poling, with multiple stages of process development and optimization to fabricate the delicate structures necessary for broadband entangled photon generation. The results presented herein update and optimize past fabrication techniques, demonstrate novel optical devices, and propose future avenues for device development. Quantum frequency conversion from 1848nm to 843nm is demonstrated for the first time, with >75% single-photon conversion efficiency. A new electric field poling methodology is presented, combining elements from multiple historical techniques with a new fast-feedback control system. This poling technique is used to fabricate the first chirped-and-apodized Type-II quasi-phase-matched structures in titanium-diffused lithium niobate waveguides, culminating in a measured phasematching spectrum that is predominantly Gaussian (R^2 = 0.80), nearly eight times broader than the unchirped spectrum, and agrees well with simulations.

A mass manufacturable impedance based, palladium doped porous silicon sensor, was fabricated for hydrogen detection. The sensor was built using electrochemical etching to produce mesoporous silicon. Four nanometers of palladium was defused directly into the porous silicon and another four nanometers of Pd was deposited on the defused surface to enhance sensing. The sensor was tested in a sealed chamber in which the impedance was measured while hydrogen in nitrogen was ranged from 0-2 percent. Unlike conventional hydrogen sensors this sensor responded at room temperature to changes in hydrogen concentration. The electrical impedance response due to adsorption and desorption of hydrogen reacted relatively quickly due to the nanoparticle nature of palladium diffusion in and Pd evaporation on porous silicon.

Η παρούσα εργασία ασχολείται με την εξομοίωση σε προγραμματιστικό περιβάλλον, της λειτουργίας συστοιχιών ηχείων κάθετης διάταξης και συγκεκριμένα για τις περιπτώσεις ευθύγραμμων (Uniform) και υβριδικού τύπου (J-Shaped) συστοιχιών, σε περιβάλλον ανοιχτών και κλειστών χώρων. Οι εξομοιώσεις που υλοποιήθηκαν επιτρέπουν την αξιολόγηση και σύγκριση των συστοιχιών σε θέματα εκπομπής, εστιάζοντας στην ηχητική κάλυψη των επιπέδων ακρόασης. Επιπλέον, αναπτύσσονται τα εργαλεία για την εξομοίωση και μελέτη του διάχυτου πεδίου που παράγεται κατα τη λειτουργία των συστοιχιών σε κλειστούς χώρους. / The current thesis is about simulating the function of Uniform and J-Shaped line arrays in open and closed space. It also allows the comparison among between the two types af arrays in terms of beaming and sound coverage especially at the audience planes. Furthermore, tools of simulation of the diffuse field are being developed.

No description available.

京都大学 / 0048 / 新制・課程博士 / 博士(情報学) / 甲第18416号 / 情博第531号 / 新制||情||94(附属図書館) / 31274 / 京都大学大学院情報学研究科複雑系科学専攻 / (主査)教授 磯 祐介, 教授 西村 直志, 教授 木上 淳, 講師 吉川 仁 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM

Le projet du gouvernement grec en 2006 d’introduire une Cour constitutionnelle pour remplacer le contrôle diffus pose le problème du choix entre le modèle américain et le modèle européen. Il n’y a pas de supériorité inhérente d’un modèle sur le plan axiologique, logique, technique et empirique. Les défauts du système américain sont amplifiés en Grèce par le contexte européen de sorte que le système grec assure la dépolitisation du contrôle mais n’assure pas la sécurité juridique. De même, il est activiste en matière socioéconomique mais il ne l’est pas concernant les droits individuels de premier rang. Par ailleurs, les mécanismes correctifs (Cour suprême spéciale, Cour plénière, Tribunal des Salaires) aggravent le problème d’irrationalité en raison du grand nombre des juges. Ils engendrent aussi des décisions provocatrices dans les domaines électoraux et judiciaires. D’autre part, la Cour constitutionnelle se heurte à l’existence d’un système américain actif, d’un contexte culturel non continental, à l’interprétation historique des principes irrévisables et à un contexte social clientéliste. Plus particulièrement, la Cour constitutionnelle proposée favorise la loi en raison de la désignation des juges uniquement par le parti majoritaire et aussi de la saisine de la Cour dans le cas de deux invalidations successives de la loi. En conclusion, il est opportun d’établir un système mixte selon la nature des lois contrôlées comprenant une Assemblée Plénière restreinte et une Cour constitutionnelle constituée parmi une liste triple. / The project of the Greek government in 2006 to introduce a Constitutional Court in order to replace the diffused control poses the problem of the choice between the American model and the European model. There is non inherent superiority of one model from axiological, logic, technical and empirical point of view. The defaults of the American system are amplified in Greece by the European context, so that the Greek system assures the depoliticization of the control but it does not assure the legal security. In addition, it is activist in the socioeconomic domain but it is self-restrained concerning the fundamental liberties. The remedial mechanisms (Supreme Special Court, Plenary Court, “Tribunal of Wages”) aggravate the problem of irrationality, because of the existence of lot of judges and they engender also provocative decisions in the electoral and judicial domain. On the other hand, the introduction of a Constitutional Court comes up against the existence of an active American system, a non continental cultural context, the historical interpretation or irrevisable principles and a clientelist social context. More particularly, the proposed Constitutional Court favors the law owning to the fact that the judges are appointed only by the majority party and that the Court intervenes after two invalidations of the law. In conclusion, it is convenient to establish a mixed system according to the nature of controlled laws including a restricted Plenary Court and a Constitutional Court constituted among a triple list.