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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Ernest Bloch’s Suites for Solo Cello: A Transcription for Solo Viola, Performer’s Edition, and Recording

January 2020 (has links)
abstract: Ernest Bloch’s Suites for Solo Cello (B. 93, 94, 97) contain a melodic-harmonic language unlike any other twentieth-century unaccompanied work, and when transcribed for viola, become meaningful additions to the existing viola repertoire. Each movement within these three works has its own distinct dancelike character, much like J.S. Bach’s Suites for Solo Cello (BWV 1007-1012). The melodies contain a persistent lyrical quality, and the harmonies are modal and reminiscent of folk music. Rather than compose an appropriate ending to Bloch’s incomplete Suite for Solo Viola (B. 101), a transcription of Bloch’s Suites for Solo Cello provides violists with more variety and opportunity for musicianship. These works present technical challenges such as rapid string crossings, sudden and vast register changes, complex rhythms and meter, and offer interpretationally rich passages. The level of these difficulties can prepare violists for more challenging twentieth-century works; thus, transcribing the Bloch Suites provides an opportunity to bridge a pedagogical divide in solo viola repertoire. This project includes the transcriptions of Bloch’s Suites for Solo Cello, a performance edition, and a recording. Included is an overview of why these works are suitable for the viola, how these arrangements help fill a pedagogical gap in the unaccompanied viola repertoire, and insight into the transcription process. The performance recording captures the accessibility of these works for violists wishing to perform them and shows the integrity and variety of each piece by programming them all on a single recital. / Dissertation/Thesis / Suite No. 1, Prelude / Suite No. 1, Allegro / Suite No. 1, Canzona / Suite No. 2, Prelude / Suite No. 2, Allegro / Suite No. 2, Andante tranquillo, Allegro / Suite No. 3, Allegro deciso / Suite No. 3, Andante / Suite No. 3, Allegro, Andante, Allegro giocoso / Doctoral Dissertation Music 2020
62

Paradigms of hope : a comparison of Ernst Bloch and Rubem Alves

Peterson, Glen B. January 1974 (has links)
No description available.
63

Twisted Particle Control and Transfer

Bawazir, Abdullah 02 June 2022 (has links)
Twisted particles carry Orbital Angular Momentum (OAM), an important property utilized to encode quantum information. The OAM of twisted photons can be trans- ferred onto condensed matter systems in the form of twisted excitons. Numerical solutions of the time-dependent Schr ̈odinger equation for a 3-arm molecular chain are used to demonstrate the manipulation of twisted excitons via an external magnetic field. We present the first design for an OAM transistor in a quasi-1D system that can be used to control the flow of OAM using the magnetic field. The underlying mechanism is the interaction between OAM and the magnetic field which leads to a orbit-resolved Bloch oscillation (ORBO). We present the semi-classical equations of motion for this phenomenon in a one-dimensional system. Unlike classical Bloch oscil- lation, an important effect in ultrafast electron dynamics, the magnet driven ORBO is not limited by electrical breakdown and can easily be observed in natural solids.
64

Role of U(1) Gauge Symmetry in the Semiconductor Bloch Equations

Parks, Andrew 25 November 2022 (has links)
The semiconductor Bloch equations (SBEs) are an insightful and well-established formalism for studying light-matter interactions in solids. When Coulomb interactions between electrons are omitted, the SBEs are simplified to a single particle model. The SBEs in this single electron approximation have been used extensively to model strong-field interactions in condensed matter. The SBEs in the length gauge provide an intuitive and numerically efficient model of high harmonic generation (HHG) in solids. In this approach, the SBEs involve Berry connections and transition dipole moments, which are gauge dependent structural quantities. This thesis studies the role of gauge symmetry in the SBEs, and how it can be exploited to facilitate efficient numerical analysis of HHG in solids. In the length gauge, the macroscopic current describing HHG can be decomposed into physically intuitive contributions. In particular, this leads to a contribution known as the "mixture" current, which has been overlooked by the HHG community until recently. We study the influence of this contribution using the analytic tight-binding model for gapped graphene. We derive an analytic gauge transformation that removes singular behaviour from the gapped graphene model, thus enabling efficient numerical integration of the SBEs. We also present an alternative approach for simulating dynamics in tight-binding models. Instead of simulating the SBEs in the usual basis of Bloch functions, we transform to the basis in which the tight-binding Hamiltonian is represented. The dipole matrix elements necessarily vanish in this basis, and the SBEs can be integrated using only the Hamiltonian matrix elements. We first generalize the SBEs to accomodate a non-diagonal Hamiltonian matrix, and we demonstrate this formalism numerically using two different tight-binding models. Finally, we derive a novel formulation of the SBEs which involve only gauge invariant matrix elements. Specifically, the Berry connections and transition dipole phases are replaced by a gauge invariant quantity known as the shift vector. This yields a fully gauge invariant description of HHG in solids, and the shift vector provides intuitive insight for HHG in systems with broken inversion symmetry. Further, the ability to describe HHG solely in terms of gauge invariant quantities raises new possibilities for tomographic reconstruction of crystal band structure, and this idea is discussed as a possible direction of future work.
65

The Musical Representation of Jewish Faith in Ernest Bloch's 1923 "Baal Shem Suite"

Swartz, Eric Gregory 05 1900 (has links)
Ernest Bloch (1880-1959) was a Swiss-American composer of music expressing his Jewish nationality. Through his music, he wanted to convey the importance of Jewish faith in countering antisemitism in the early 20th century. This thesis focuses on Bloch's employment of Jewish liturgical modes and melodic embellishments in his 1923 Baal Shem Suite. The Baal Shem Suite is a three-movement piece for violin and piano and is named after the Baal Shem Tov, founder of the Jewish Hasidic movement. As discussed in the document, the piece portrays Hasidic traditions. This thesis provides a Schenkerian analysis of motivic ideas derived from the Jewish modes and their embellishments, while also describing how both elements evoke Jewish spirituality. The document also identifies resemblances between motives in Bloch's suite and preexisting Jewish melodies. As the thesis states, Bloch likely drew inspiration from cantillation of the Hebrew Bible. He was also likely inspired by 19th-century "Jewish pieces" by Franz Schubert and another Jewish composer named David Popper. The document also references 20th century Jewish composers after Bloch who were likely inspired by his Baal Shem Suite. The thesis also identifies the liturgical modes and embellishments employed in some of the composers' musical works.
66

Pulsed field studies of magnetotransport in semiconductor heterostructures

Dalton, Karen Sonya Helen January 1999 (has links)
No description available.
67

Elastodynamic homogenization of periodic media / Homogénéisation élastodynamique de milieux périodiques

Nassar, Hussein 01 October 2015 (has links)
La problématique récente de la conception de métamatériaux a renouvelé l'intérêt dans les théories de l'homogénéisation en régime dynamique. En particulier, la théorie de l'homogénéisation élastodynamique initiée par J.R. Willis a reçu une attention particulière suite à des travaux sur l'invisibilité élastique. La présente thèse reformule la théorie de Willis dans le cas des milieux périodiques, examine ses implications et évalue sa pertinence physique au sens de quelques ``conditions d'homogénéisabilité'' qui sont suggérées. En se basant sur les résultats de cette première partie, des développements asymptotiques approximatifs de la théorie de Willis sont explorés en relation avec les théories à gradient. Une condition nécessaire de convergence montre alors que toutes les branches optiques de la courbe de dispersion sont omises quand des développements asymptotiques de Taylor de basse fréquence et de longue longueur d'onde sont déployés. Enfin, une nouvelle théorie de l'homogénéisation est proposée. On montre qu'elle généralise la théorie de Willis et qu'elle l'améliore en moyenne fréquence de sorte qu'on retrouve certaines branches optiques omises auparavant. On montre également que le milieu homogène effectif défini par la nouvelle théorie est un milieu généralisé dont les champs satisfont une version élastodynamique généralisée du lemme de Hill-Mandel / The recent issue of metamaterials design has renewed the interest in homogenization theories under dynamic loadings. In particular, the elastodynamic homogenization theory initiated by J.R. Willis has gained special attention while studying elastic cloaking. The present thesis reformulates Willis theory for periodic media, investigates its outcome and assesses its physical suitability in the sense of a few suggested ``homogenizability conditions''. Based on the results of this first part, approximate asymptotic expansions of Willis theory are explored in connection with strain-gradient media. A necessary convergence condition then shows that all optical dispersion branches are lost when long-wavelength low-frequency Taylor asymptotic expansions are carried out. Finally, a new homogenization theory is proposed to generalize Willis theory and improve it at finite frequencies in such a way that selected optical branches, formerly lost, are recovered. It is also proven that the outcome of the new theory is an effective homogeneous generalized continuum satisfying a generalized elastodynamic version of Hill-Mandel lemma
68

O elo entre o pensamento e a ação em Marc Bloch: um estudo sobre o nacionalismo e a experiência da Segunda Guerra Mundial / A study about nationalism and World War II experience

Jougi Guimarães Yamashita 01 October 2010 (has links)
O presente trabalho pretende analisar a força e os limites do nacionalismo na trajetória de Marc Bloch. A partir da problematização de sua memória post-mortem, construída por seus amigos e familiares, procura-se entender como a imagem de Bloch se consagrou na França como a de alguém que sacrificou sua vida em nome desta comunidade imaginada. A partir daí, busca-se compreender que elementos de sua trajetória foram responsáveis por dar espaço a essa construção. É aí que se apresentam as múltiplas identidades de Marc Bloch soldado, judeu, resistente, historiador, cidadão. Por fim, buscar-se-á, a partir da análise de seu livro Létrange défaite, analisar como o próprio historiador construiu a imagem de si mesmo e da França de sua época.
69

O elo entre o pensamento e a ação em Marc Bloch: um estudo sobre o nacionalismo e a experiência da Segunda Guerra Mundial / A study about nationalism and World War II experience

Jougi Guimarães Yamashita 01 October 2010 (has links)
O presente trabalho pretende analisar a força e os limites do nacionalismo na trajetória de Marc Bloch. A partir da problematização de sua memória post-mortem, construída por seus amigos e familiares, procura-se entender como a imagem de Bloch se consagrou na França como a de alguém que sacrificou sua vida em nome desta comunidade imaginada. A partir daí, busca-se compreender que elementos de sua trajetória foram responsáveis por dar espaço a essa construção. É aí que se apresentam as múltiplas identidades de Marc Bloch soldado, judeu, resistente, historiador, cidadão. Por fim, buscar-se-á, a partir da análise de seu livro Létrange défaite, analisar como o próprio historiador construiu a imagem de si mesmo e da França de sua época.
70

Oscillations de Bloch d'atomes ultra-froids : application aux mesures de haute précision / Bloch oscillations of ultra-cold atoms : application to high-precision measurements

Andia, Manuel 25 September 2015 (has links)
Ce travail de thèse se développe autour de trois expériences. La première concerne la mesure du rapport h/m entre la constante de Planck et la masse d'un atome de rubidium. Dans le cadre de l'étude détaillée des effets systématiques, tels que la phase de Gouy ou l'effet Zeeman quadratique, nous avons développé une nouvelle source laser compacte et puissante (12W@780nm) permettant de réduire l'effet de la phase de Gouy d'un facteur 4. La deuxième expérience a porté sur la démonstration d'un nouveau schéma de gravimètre compact, s'appuyant sur les oscillations de Bloch pour faire léviter les atomes. Une mesure de l'accélération locale de la pesanteur a été réalisée avec une sensibilité préliminaire très prometteuse de 4.7E-7 g en 1s. La troisième expérience a permis d'obtenir un interféromètre atomique symétrique grâce à la technique de double diffraction Raman. Nous avons réalisé la chaîne de fréquences et le montage optique pour l'intégration de séparatrices à grand transfert d'impulsion (LMTBS) à base d'oscillations de Bloch. / This work developed around three experiments. The first one concerned the measurement of the ratio h/m between Planck's constant and rubidium atomic mass. We have carried out a thorough study of systematic effects, such as the Gouy phase or the quadratic Zeeman effect. The development of a new compact and high-power laser source (12W@780nm) allowed to decrease the effect of Gouy phase by a factor of 4. The second experiment revolved around the realization of a compact and precise gravimeter, using Bloch oscillations to maintain atoms against gravity. This allowed for a measurement of local gravity acceleration with a promising preliminary sensitivity of 4.7E-7 g in 1s. Finally, the third experiment consisted in the realization of the double diffraction technique, with the aim of implementing Bloch-oscillation-based large momentum transfer beamsplitters.

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