In the educational literature on peer effects, attention has been brought to the fact that the mechanisms creating peer effects are still to a large extent hidden in obscurity. The hypothesis in this study is that the Frame Factor Theory can be used to explain these mechanisms. At heart of the theory is the concept of “time needed” for students to learn a certain curricula unit. The relations between class-aggregated time needed and the actual time available, steers and hinders the actions possible for the teacher. Further, the theory predicts that the timing and pacing of the teachers’ instruction is governed by a “steering criterion group” (SCG), namely the pupils in the 10th-25th percentile of the aptitude distribution in class. The class composition hereby set the possibilities and limitations for instruction, creating peer effects on individual outcomes. To test if the theory can be applied to the issue of peer effects, the study employs multilevel structural equation modelling (M-SEM) on Swedish TIMSS 2015-data (Trends in International Mathematics and Science Study; students N=3761, teachers N=179). Using confirmatory factor analysis (CFA) in the SEM-framework, latent variables are specified according to the theory, such as “limitations of instruction” from TIMSS survey items. The results indicate a good model fit to data of the measurement model. The SEM-model verify a strong relation between the mean level of the SCG and the latent variable of limitations on instruction, a variable which in turn has a great impact on individual students’ test results. Thus, the analysis indicates a confirmation of the predictions derived from the frame factor theory and reveals that one of the important mechanisms creating peer effects in student outcomes is the effect the class composition has upon the teachers’ instruction in class.

The pieces discussed throughout this dissertation provide evidence of the evolution of the fanfare and the ability of the fanfare, as a form, to accept modern compositional techniques. While Britten’s Fanfare for St. Edmundsbury maintains the harmonic series, it does so by choice rather than by the necessity in earlier music played by the baroque trumpet. Stravinsky’s Fanfare from Agon applies set theory, modal harmonies, and open chords to blend modern techniques with medieval sounds. Satie’s Sonnerie makes use of counterpoint and a rather unusual, new characteristic for fanfares, soft dynamics. Ginastera’s Fanfare for Four Trumpets in C utilizes atonality and jazz harmonies while Stravinsky’s Fanfare for a New Theatre strictly coheres to twelve-tone serialism. McTee’s Fanfare for Trumpets applies half-step dissonance and ostinato patterns while Tower’s Fanfare for the Uncommon Woman demonstrates a multi-section work with chromaticism and tritones. By applying modern compositional techniques to an older, abstract form, composers have maintained the original aesthetic while allowing for fanfares to be used as concert music. This document adds to the limited body of scholarly writing on modern fanfares.

The lecture recital was given January 22, 1977. A discussion of Elliott Carter's Piano Sonata emphasized those compositional techniques which foreshadowed important compositional procedures in many of his later works. The following compositions were discussed: Concerto for Orchestra, Double Concerto for Harpsichord and Piano with Two Chamber Orchestras, 8 Etudes and a Fantasy for Woodwind Quartet, Holiday Overture, Piano Concerto, Sonata for Flute, Oboe, Cello, and Harpsichord, Sonata for Violoncello and Piano, String Quartet No. 1, String Quartet No. 2, String Quartet No. 3, Variations for Orchestra. The Piano Sonata was Ty and Schumann. In addition to the lecture recital, three public solo recitals were performed. The first solo recital, performed on April 2, 1973, consisted of works by Bartok, Debussy The second solo recital, performed on October 28, 1974, included works by Bach and Liszt. The final solo recital, performed on March 7, 1976, consisted of works by Beethoven and Chopin. All four programs were recorded on magnetic tape and are filed, along with the written version of the lecture recital, as part of the dissertation. performed.

Accurate phase behavior modeling of hydrocarbon and aqueous mixtures plays a critical role in simulation of compositional flow in subsurface reservoirs, such as miscible gas flooding and CO2 sequestration. As Michelsen proposed his groundbreaking works in stability test and phase split calculation, PT flash calculation has been well developed in the past four decades and become the most popular flash technique. However, as research interests move to more complicated reservoir fluids, some inherent drawbacks of PT flash formulations show up and recent researches focus on a promising alternative called VT flash calculation. In this thesis, VT flash calculation is used in place of PT flash to model phase behaviors of hydrocarbon and aqueous mixtures. A dynamical model, together with a thermodynamically stable numerical algorithm, is developed to calculate equilibrium phase amounts and compositions with/without capillary effect to simulate phase behaviors of unconventional/conventional hydrocarbon mixtures. In order to model water-containing mixtures, the cubic equation of state is replaced by the Cubic-PlusAssociation equation of state, and a salt-based Cubic-Plus-Association model is developed to calculate phase behaviors of CO2-brine systems. The combination of VT flash calculation and the salt-based Cubic-Plus-Association model accurately estimate CO2 solubility in both single- and mixed-salt solutions, and it exhibits close prediction accuracy with a more sophisticated electrolyte Cubic-Plus-Association model. At the end, the ultimate goal is to develop an efficient two-phase VT-flash compositional flow algorithm. The multilayer nonlinear elimination method is used to remove locally high nonlinearities based on the feedback of intermediate Newton solutions. To further improve the computational efficiency, a modified shadow region method is used to bypass unnecessary stability tests. Although nonlinear elimination fails to fully resolve the convergence issue, which roots in the nondifferentiable equilibrium pressure at the points of phase boundary, the number of time refinements is significantly reduced and the improved VT-flash compositional flow algorithm with multilayer nonlinear elimination method successfully simulates a number of numerical examples with and without gravity.

* / Dissertation (MMus)--University of Pretoria, 2017. / Music / MMus / Unrestricted

English abstract This work focuses on high pressure atoll garnet-bearing metabasites from the central part of Krušné hory Mts. in Saxothuringian zone of Bohemian Massif. Eclogite bodies are interpreted as a part of alochtonnous units, which were dragged into the high pressure conditions of subduction zone during a subduction of Saxothuringian oceanic crust under the Teplá-Barrandien Unit and subsequently they were exhumed into upper parts of subduction- collisional system. Main mineral assemblage of eclogites consists of omphacite, garnet, quartz and amphibole which replaces grains of omphacite. Minor minerals present are rutile, ilmenite, talc a chlorite. Zircon, apatite, paragonite, pyrite, plagioclase, albite and monazite are enclosed in porphyroblasts of garnets. Grains of garnet frequently form the atoll structures, where its central part of a grain is replaced by new minerals of matrix and rim part stays preserved. Based on compositional profiles and mapping of major and trace elements, two evolution phases of garnet were distinguished. Older garnet (I) forms mainly preserved cores of garnet and on the contrary younger garnet (II) is present on rims or also replaces garnet I in the core part of a grain. Garnet I has higher amounts of Ca and Mn but lower Mg and Fe than garnet II. Preserved grains of...

John Cage’s Concerto for Prepared Piano and Chamber Orchestra (1950-51) holds a unique position within the composer’s oeuvre as the first work based in part on chance-derived compositional procedures. Cage entered into such practice gradually, incrementally abandoning subjective taste and personal expression through the course of the work. Drawing from the philosophical framework provided by Cage’s "Lecture on Nothing" (1950) and "Lecture on Something" (c. 1951-52), this thesis explores the aesthetic foundations of the concerto and examines Cage’s compositional methodology throughout its three movements. Special attention is paid to the procedure underlying the first movement, whose analysis is based largely on the composer’s manuscript materials for the work.

This is a study of Bartók's compositional process as it relates to the Improvisations, Op. 20. The study, which focuses on the analysis of the draft manuscript 50PS1, compares the draft and other relevant sources with the final composition. Bartók's framework for the entire Improvisations is based on a compositional strategy of pairing individual improvisations combined with systematic revision of the draft copy by the introduction of tritones as tonal equivalents and movement by fifths from semitones, to achieve structural coherence in the individual improvisations. The tonic-dominant relationship is used to rearrange the individual improvisations in the draft and tritones as tonal equivalents are used to propel the movement between the improvisations to produce a coherent whole.

This dissertation focuses on the first Parable of Vincent Ludwig Persichetti, written for alto flute in 1965. Persichetti spent from 1965 to 1986 (almost the last twenty years of his life) composing twenty-four additional Parables for various solo instruments, instrumental combinations, and even one in the form of an opera.

The lecture recital was given April 2, 1973. A discussion of Liszt's late piano works included information about specific compositional techniques and innovations which influenced twentieth-century composers. Five selections of the late works were performed by memory. In addition to the lecture recital, three public solo recitals were performed. The first solo recital, performed on April 9, 1972, consisted of works by Haydn, Beethoven, Ravel, and Chopin. The second solo recital, performed on August 4, 1974, included works by Beethoven, Debussy, and Brahms. The final solo recital, performed on April 5, 1976, consisted of works by Bach, Chopin, and Prokofieff. All four programs were recorded on magnetic tape and are filed, along with the written version of the lecture recital, as part of the dissertation.