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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.
41

Odolnost asfaltových pojiv proti stárnutí / Resistance of bituminous binder to ageing

Rous, Vojtěch January 2013 (has links)
Asphalt binder ageing and experiences with various ageing methods from abroad are described in this thesis. The practical part deals with the RTFOT aging and with the influence of the duration of this test. The comparison of test results is conducted before and after the aging by values of needle penetration, elastic recovery, softening point and resilience tests are evaluated and compared.
42

New devices for noise control and acoustic cloaking

García Chocano, Víctor Manuel 13 July 2015 (has links)
[EN] The aim of this work is to design new acoustic devices based on arrangements of scattering units. First, the use of sonic crystals as noise barriers for traffic noise control is comprehensively analyzed. Due to the limitations of the conventional structures based on rigid scatterers, the inclusion of absorbing elements is proposed. Two different types of absorbers are here considered: porous materials and microperforated plates. In the first case, the attenuation characteristics of barriers made with cylinders containing rubber crumb is analyzed. The second proposal is based on the construction of cylindrical microperforated shells. Analytical approaches modelling the behavior of the barriers have been developed in both cases. These models show a satisfactory agreement with the corresponding experimental realizations. Finally, it is performed an optimization process in order to obtain efficient sound barriers intended to attenuate traffic noise. Another application considered in this work is the construction of cloaks to render objects acoustically invisible. In particular, cloaks made with rigid inclusions are designed to operate with airborne sound. The first proposal consists of a cloak that utilizes the temperature of the background to control the properties of the effective medium. In addition, two and three-dimensional cloaks have been developed through the scattering cancellation technique. These devices have been designed by means of an optimization procedure and their performance has been experimentally demonstrated. / [ES] El objetivo de este trabajo es el diseño de nuevos dispositivos acústicos basados en disposiciones de centros de dispersión. En primer lugar, el uso de cristales sónicos como barreras acústicas para el control de ruido de tráfico es analizado en detalle. Debido a las limitaciones que presentan las estructuras convencionales basadas en centros de dispersión rígidos, se propone la inclusión de elementos absorbentes en los mismos. Se han considerado dos tipos distintos de absorbente: materiales porosos y placas microperforadas. En el primer caso se analizan las propiedades atenuadoras de barreras formadas por cilindros que contienen granza de caucho. La segunda solución se basa en la construcción de coronas microperforadas. En ambos casos se han desarrollado modelos analíticos que permiten determinar el comportamiento de las barreras. Dichos modelos muestran un acuerdo satisfactorio con las correspondientes realizaciones experimentales. Finalmente se ha realizado un proceso de optimización con objeto de obtener barreras eficientes para la atenuación de ruido de tráfico. Otra aplicación considerada en este trabajo es el desarrollo de dispositivos de invisibilidad acústica. Concretamente se pretenden diseñar mantos constituidos con elementos rígidos para ondas acústicas en aire. La primera propuesta consiste en un manto que utiliza la temperatura del medio externo para controlar sus propiedades efectivas. Además se han desarrollado mantos en dos y tres dimensiones a través de la técnica de cancelación de la dispersión. Los diseños han sido realizados por medio de un proceso de optimización y su funcionamiento ha sido demostrado experimentalmente. / [CA] L'objectiu d'aquest treball és el disseny de nous dispositius acústics basats en disposicions de centres de dispersió. En primer lloc, l'ús de vidres sònics com barreres acústiques per al control de soroll de trànsit és analitzat en detall. A causa de les limitacions que presenten les estructures convencionals basades en centres de dispersió rígids, es proposa la inclusió d'elements absorbents en els mateixos. S'han considerat dos tipus diferents de absorbent: materials porosos i plaques microperforades. En el primer cas s'analitzen les propietats atenuadores de barreres formades per cilindres que contenen gransa de cautxú. La segona solució es basa en la construcció de corones microperforades. En tots dos casos s'han desenvolupat models analítics que permeten determinar el comportament de les barreres. Aquests models mostren un acord satisfactori amb les corresponents realitzacions experimentals. Finalment s'ha realitzat un procés d'optimització per tal d'obtenir barreres eficients per l'atenuació de soroll de trànsit. Una altra aplicació considerada en aquest treball és el desenvolupament de dispositius d'invisibilitat acústica. Concretament es pretenen dissenyar mantells constituïts amb elements rígids per ones acústiques en aire. La primera proposta consisteix en un mantell que utilitza la temperatura del medi extern per controlar les seves propietats efectives. A més s'han desenvolupat mantells en dues i tres dimensions a través de la tècnica de cancel·lació de la dispersió. Els dissenys han estat realitzats per mitjà d'un procés d'optimització i el seu funcionament ha estat demostrat experimentalment. / García Chocano, VM. (2015). New devices for noise control and acoustic cloaking [Tesis doctoral]. Editorial Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/53026 / TESIS / Premios Extraordinarios de tesis doctorales
43

Hur lät dinosaurierna? : En analys av George Crumbs VOX BALAENAE - ett stycke som gestalatar förhistoriska djur och miljöer.

Eskeby, Emma January 2023 (has links)
I mitt kandidatarbete har jag genomfört en analys av George Crumbs (1929-2022) verk VOX BALAENAE (1971) som en form av auditiv paleokonst. Paleokonst är en genre inom bildkonsten som syftar till att med hjälp av paleontologi skapa bilder av hur förhistorisk flora och fauna kan ha sett ut. Andra satsen i VOX BALAENAE är en tema- och variationssats, Crumb har namngivit variationerna efter geologiska tidsåldrar, medan de kringliggande satserna är tillägnade själva tidens början och slut. Mitt fokus ligger på att analysera och jämföra musiken med den geologiska tidsålder som den gestaltar. Syftet med min studie är att undersöka hur Crumb musikaliskt gestaltar de geologiska tidsåldrarna och att se om förståelse av detta kan hjälpa mig att tolka och framföra stycket på ett mer meningsfullt sätt. Genom att analysera Crumbs musikaliska gestaltning av tidsperioderna kan jag få en djupare förståelse av hur musiken kan användas för att gestalta historiska epoker vilket i sin tur kan ge nya insikter om kopplingar mellan vetenskap och konst. Crumb använder sig av rytmik och kopplingarmellan fraser för att gestalta evolutionen samt skapar olika klangvärldar med hjälp av instrumentering och preparering av piano för att skapa musikaliska ljudlandskap. Att analysera ett verk i noggrann detalj är inte nödvändigtvis till gagn för det slutliga framförandet. Arbetet har vållat mig stor ångest och ibland hindrat mig från att tolka materialet ur ett enbart musikaliskt perspektiv. / <p>Ljudinspelning från examenskonsert 26/5-2023</p><p>VOX BALAENAE (1971) - George Crumb (1929-2022)</p><p>Emma Eskeby - flöjt</p><p>Hedvig Bengtsson - cello</p><p>Octavian Leyva Dragomir - piano</p>
44

The Effects of BAM as an Adsorptive Media on Phosphorus Removal in Stormwater

Salamah, Sultan 01 January 2014 (has links)
To maintain the quality of receiving water bodies, it is desirable to remove total phosphorus (TP) in stormwater runoff. Many media filtration technologies have been developed to achieve TP and soluble reactive phosphorus (SRP) removal. Efficient media adsorption is essential to insure control of stormwater phosphorus inputs to the receiving water body. This project develops and analyzes a functionalized Biosorption Media (BAM) to remove phosphorus species from stormwater runoff. One goal of this project is to find the BAM values for coefficients such as maximum adsorption capacity (QM: 4.35E-05) for the media through SRP isotherm equilibrium experiments using the Langmuir and Freundlich models. In addition, an upflow column experiment was also performed to study BAM nutrient removal from stormwater runoff. Finally, the information from the isotherm and the column experiments are used to estimate the life expectancy or quantity required of the media, and to define the effectiveness of BAM in phosphorus removal. The result of this study shows that BAM is a feasible stormwater treatment that can remove 60% SRP and > 40% TP at temperature between 21-23°C. The media is adequately modeled by both the Langmuir and the Freundlich models over the concentration range of interest in stormwater.
45

A Kinetics Study Of Selected Filtration Media For Nutrient Removal At Various Temperatures

Henderson, Elizabeth 01 January 2008 (has links)
In recent years the nutrient levels of the Upper Floridan aquifer have been increasing (USGS, 2008). An example of this is found in Ocala, Florida where Silver Springs nitrate concentrations have risen from 0.5 mg/L in the 1960 s to approximately 1.0 mg/L in 2003 (Phelps, 2004). Because stormwater is a contributor to surficial and groundwater aquifer recharge, there is an increasing need for methods that decrease nitrogen and phosphorus levels. A laboratory column study was conducted to simulate a retention pond with saturated soil conditions. The objectives of the column studies reported in this thesis were to investigate the capabilities of a natural soil and soil augmentations to remove nitrogen and phosphorus for a range of concentrations at three different temperatures. An analytical attempt to model the columns through low order reaction kinetics and derive the corresponding temperature conversion constant to relate the rate constants is also presented. The Media Mixes were selected through a process of research, preliminary batch testing and then implemented in column studies. Three columns measuring three feet in length and 6 inches outer diameter were packed with a control and two media mixes. Media Mix 1 consisted of 50% fine sand, 30% tire crumb, 20% sawdust by weight and Media Mix 2 consisted of 50% fine sand, 25% sawdust, 15% tire crumb, 10% limestone by weight. The control column was packed with natural soil from Hunter s Trace retention pond located in Ocala, Florida. The reaction rates for nitrate are best modeled as first order for Media Mix 1, and zero order for the Control and Media Mix 2. The reaction rates for orthophosphate are best modeled as zero order, second order and first order for the Control, Media Mix 1, and Media Mix 2 respectively. The best overall media for both nitrate and orthophosphate removal from this study would be Media Mix 1. Media Mix 2 does have the highest average orthophosphate removal of all the mixes for all of the temperatures; however Media Mix 1 outperforms Mix 2 for the other two temperatures. The best column for Nitrate removal is the Media Mix 1 column. The temperature conversion factors for nitrate were found to be 1.11, 1.1, and 1.01 for Media Mix 1, the Control and Media Mix 2 respectively. The temperature conversion factors for orthophosphate were found to be 1.02, 0.99, and 0.95. As well as temperature conversion factors, the activation energies and frequency factors for the Arrhenius Equation were investigated. Average values corresponding to each column, species, and temperature would be inaccurate due to the large variation in calculated values.
46

The Influence of Bela Bartok on Symmetry and Instrumentation in George Crumb's Music for a Summer Evening with Three Recitals of Selected Works of Abe, Berio, Dahl, Kessner, Miki, Miyoshi, and Others

Kingan, Michael Gregory 08 1900 (has links)
The purpose of this document is to investigate the influence of Bela Bartok's music, specifically the Sonata for Two Pianos and Percussion, on George Crumb's Music for a Summer Evening. It concentrates on two specific areas: 1) the role of symmetry and 2) instrumentation. These two items were stressed during an interview with Crumb by the author, which is appended to the paper.
47

Caractérisation des phénomènes d’érosion et de dispersion : développement d’essais et applications pratiques / Characterization of erosion and dispersion : test development and practical applications

Haghighi, Iman 24 September 2012 (has links)
Les processus érosifs constituent la cause majeure des ruptures des ouvrages hydrauliques comme les digues ou les barrages en terre. Ils touchent également de nombreux ouvrages comme les remblais d'infrastructure de transport ou les fondations de piles de ponts. Les phénomènes d'érosion sont des processus complexes qui dépendent de multiples paramètres. Il est donc indispensable de les caractériser au travers d'essais dédiés. Deux mécanismes principaux d'érosion sont généralement distingués sur les ouvrages linéaires en terre : l'érosion interne et la surverse. La dispersivité du sol est également un facteur important dans ces processus. Le présent travail étudie ces phénomènes à l'aide de trois dispositifs expérimentaux : l'essai d'érosion de trou (HET « Hole Erosion Test ») qui étudie l'agrandissement d'un canal circulaire par analogie à l'érosion interne (érosion de conduit), l'érodimètre à jets mobiles (MoJET « Mobile Jets Erosion Test ») qui érode la surface du sol par des jets perpendiculaires avec des analogies à l'érosion de surface et l'essai d'émiettage amélioré (ECT « Enhanced Crumb Test ») qui évalue le potentiel de désagrégation d'une texture de sol en absence de sollicitation mécanique. Dans une première partie, nous nous sommes intéressés à développer et améliorer ces trois dispositifs expérimentaux, leur protocole d'essai ainsi que leur interprétation pour une application plus pertinente sur les ouvrages. Ainsi, pour le HET, une nouvelle méthode d'interprétation indépendante de l'hydraulique de l'écoulement est proposée. Le dispositif a également été adapté pour réaliser des essais sur des éprouvettes peu perturbées et les plages de sollicitations ont été étendues pour rendre l'essai à la fois applicable sur des sols très résistants et sur des sédiments très sensibles à l'érosion. Le dispositif de MoJET a été utilisé pour effectuer des campagnes d'essais sur ouvrages pilotes avec un mode opératoire révisé. Enfin, le dispositif d'essai d'émiettage a été amélioré pour effectuer un suivi temporel quantitatif de la désagrégation du sol dans l'eau et un protocole a été défini pour la réalisation d'essais sur les sols reconstitués ou prélevés. Dans une seconde partie, les différentes méthodes d'expérimentation ont été appliquées sur deux études pratiques. La première étude porte sur l'utilisation de chaux pour traiter les sols utilisés dans les ouvrages hydrauliques. Nous montrons au travers de campagnes d'essais en laboratoire et sur ouvrages pilotes que l'utilisation d'un tel traitement diminue considérablement la sensibilité à l'érosion des sols traités. La seconde étude porte sur l'influence de la salinité de l'eau (environnante ou constitutive du sol) sur les phénomènes d'érosion et de dispersion. L'utilisation des différents essais a permis de discuter l'influence de plusieurs paramètres et de caractériser le comportement des sols face aux différents aspects des processus érosifs / Erosion Erosion processes are the major cause of failures in hydraulic earthworks such as levees and earth dams. They affect as well many structures including transport infrastructure embankments or foundations of bridge piers. Erosion phenomena are complex processes depending on multiple parameters. It is therefore essential to characterize them through direct measurements. Two principal mechanisms of erosion are generally distinguished on earthworks: internal erosion and overtopping. Dispersivity of the soil is also an important factor in these processes. The present work studies these phenomena using three experimental devices: the Hole Erosion Test (HET), which examines the enlargement of a circular channel simulating internal erosion (piping), the Mobile Jets Erosion Test (MoJET) that erodes the by jets perpendicularly to soil surface by analogy to surface erosion and the Enhanced Crumb Test (ECT) which quantifies the disintegration potential of a soil texture in the absence of mechanical loads. In the first part, we were interested in developing and improving these three experimental devices, their testing protocol and interpretation methods for a more relevant application on earthworks. Thus, for the HET, a new interpretation method independent of the hydraulic flow is proposed. The device has also been adapted to perform tests on undisturbed soil samples and the ranges of stresses have been extended to make the test applicable from highly sensitive sediments to highly resistant soils. The MoJET device was used to perform series of tests on problematic earthworks with a revised procedure. At last, the Crumb Test has been enhanced to perform quantitative monitoring of disaggregation of soil specimens in water and a protocol has been defined for conducting tests on reconstituted or undisturbed soil specimens. In the second part, the different test methods were applied to two practical studies. The first study focuses on the application of lime treatment to hydraulic earthworks. It has been found through series of tests in the laboratory and on experimental earthworks that the application of such treatment technique reduces significantly the sensitivity to erosion of soils. The second study examined the influence of water salinity (pore water or eroding/permeant water) on erosion and dispersion. The use of different tests led to discuss the influence of several parameters and characterize the behavior of soils in various aspects of erosion processes
48

Caracterização do comportamento fluência-recuperação de ligantes asfálticos modificados virgens e envelhecidos / Characterization of the creep-recovery behavior of unaged and short-term aged modified asphalt binders

Domingos, Matheus David Inocente 13 December 2011 (has links)
O ensaio de fluência e recuperação sob tensão múltipla (MSCR) é resultado do aperfeiçoamento do ensaio de fluência repetida e recuperação (RCRT) pela Administração Rodoviária Federal dos Estados Unidos (FHWA) e tem por objetivo avaliar o percentual de recuperação, a compliância não-recuperável e a dependência dos ligantes asfálticos, especialmente os modificados, quanto ao nível de tensão. O MSCR foi utilizado neste estudo para caracterizar o comportamento fluência-recuperação de diversos ligantes asfálticos modificados virgens e envelhecidos a curto prazo. Foi empregado o procedimento da norma ASTM D7405, que prescreve os tempos de fluência e recuperação de 1 e 9 s, e avaliada a influência do aumento dos tempos de fluência e recuperação de 1 e 9 s para 2 e 18 s nas propriedades dos ligantes asfálticos envelhecidos a curto prazo. Além dos resultados destes ensaios, foram utilizados os valores de penetração, ponto de amolecimento, viscosidade rotacional, penetração retida, incremento do ponto de amolecimento, incremento de viscosidade e perda de massa para verificar quais ligantes asfálticos apresentam melhor comportamento à luz das propriedades e parâmetros considerados. Foram preparados doze materiais modificados e de classificação PG 76-XX tendo como base um CAP 50/70 de classificação PG 64-XX: CAP+PPA, CAP+Elvaloy+PPA, CAP+borracha, CAP+borracha+PPA, CAP+SBS, CAP+SBS+PPA, CAP+EVA, CAP+EVA+PPA, CAP+PE, CAP+PE+PPA, CAP+SBR e CAP+SBR+PPA. O CAP+Elvaloy+PPA apresenta, em um contexto geral, o melhor desempenho nas propriedades e parâmetros analisados em virtude dos bons resultados do percentual de recuperação e da compliância não-recuperável e das menores sensibilidades à tensão. O CAP+PE apresenta o pior desempenho geral dentre os materiais estudados, na medida em que os resultados do percentual de recuperação e da compliância não-recuperável deste ligante asfáltico são ruins e as sensibilidades ao aumento nos tempos de fluência e recuperação de 1 e 9 s para 2 e 18 s são elevadas. Ao ordenar os ligantes asfálticos do melhor para o pior à luz das propriedades e parâmetros considerados, o resultado é: CAP+Elvaloy+PPA, CAP+EVA, CAP+EVA+PPA, CAP+PPA, CAP+borracha+PPA, CAP+SBR+PPA, CAP+SBS+PPA, CAP+SBS, CAP+PE+PPA, CAP+borracha, CAP+SBR, CAP 50/70 e CAP+PE. / The multiple stress creep and recovery (MSCR) test is the result of a refinement of the repeated creep and recovery test (RCRT). This refinement was performed by the United States Federal Highway Administration (FHWA) with the aim of evaluating the percent recovery, the non-recoverable compliance and the stress dependency of asphalt binders, especially the modified ones. The MSCR test was applied in this study in order to characterize the creep-recovery behavior of unaged and short-term aged modified asphalt binders. The test procedure prescribed in ASTM D7405 specification was adopted and, to evaluate the influence of a greater creep-recovery time in the behavior of asphalt binders, the creep and recovery times of 2 and 18 s were also adopted in additional tests. The results of these tests, as well as the penetration, softening point, rotational viscosity, retained penetration, softening point increase, viscosity increase and mass loss data and mixing and compaction temperatures, were used with the objectives of ranking the asphalt binders and checking the ones with the best results in the parameters and properties considered. By using a PG 64-XX base asphalt-binder of 50/70 penetration grade, the following PG 76-XX odified asphalt binders were prepared: AC+PPA, AC+Elvaloy+PPA, AC+crumb rubber, AC+crumb rubber+PPA, AC+SBS, AC+SBS+PPA, AC+EVA, AC+EVA+PPA, AC+PE, AC+PE+PPA, AC+SBR and AC+SBR+PPA. In general, AC+Elvaloy+PPA has the best results in the parameters and properties considered in this study, especially due to the good results in the percent recovery and non-recoverable compliance and the lower stress sensitivity. In general, AC+PE has the worst results among the asphalt binders considered in this work, due to the facts that the percent recovery and non-recoverable compliance results are not good and the sensitivities to the creep-recovery times are high. By taking the results of this study and ranking the asphalt binders from the best to the worst, the following sequence is obtained: AC+Elvaloy+PPA, AC+EVA, AC+EVA+PPA, AC+PPA, AC+crumb rubber+PPA, AC+SBR+PPA, AC+SBS+PPA, AC+SBS, AC+PE+PPA, AC+crumb rubber, AC+SBR, neat AC and AC+PE.
49

Caracterização do comportamento fluência-recuperação de ligantes asfálticos modificados virgens e envelhecidos / Characterization of the creep-recovery behavior of unaged and short-term aged modified asphalt binders

Matheus David Inocente Domingos 13 December 2011 (has links)
O ensaio de fluência e recuperação sob tensão múltipla (MSCR) é resultado do aperfeiçoamento do ensaio de fluência repetida e recuperação (RCRT) pela Administração Rodoviária Federal dos Estados Unidos (FHWA) e tem por objetivo avaliar o percentual de recuperação, a compliância não-recuperável e a dependência dos ligantes asfálticos, especialmente os modificados, quanto ao nível de tensão. O MSCR foi utilizado neste estudo para caracterizar o comportamento fluência-recuperação de diversos ligantes asfálticos modificados virgens e envelhecidos a curto prazo. Foi empregado o procedimento da norma ASTM D7405, que prescreve os tempos de fluência e recuperação de 1 e 9 s, e avaliada a influência do aumento dos tempos de fluência e recuperação de 1 e 9 s para 2 e 18 s nas propriedades dos ligantes asfálticos envelhecidos a curto prazo. Além dos resultados destes ensaios, foram utilizados os valores de penetração, ponto de amolecimento, viscosidade rotacional, penetração retida, incremento do ponto de amolecimento, incremento de viscosidade e perda de massa para verificar quais ligantes asfálticos apresentam melhor comportamento à luz das propriedades e parâmetros considerados. Foram preparados doze materiais modificados e de classificação PG 76-XX tendo como base um CAP 50/70 de classificação PG 64-XX: CAP+PPA, CAP+Elvaloy+PPA, CAP+borracha, CAP+borracha+PPA, CAP+SBS, CAP+SBS+PPA, CAP+EVA, CAP+EVA+PPA, CAP+PE, CAP+PE+PPA, CAP+SBR e CAP+SBR+PPA. O CAP+Elvaloy+PPA apresenta, em um contexto geral, o melhor desempenho nas propriedades e parâmetros analisados em virtude dos bons resultados do percentual de recuperação e da compliância não-recuperável e das menores sensibilidades à tensão. O CAP+PE apresenta o pior desempenho geral dentre os materiais estudados, na medida em que os resultados do percentual de recuperação e da compliância não-recuperável deste ligante asfáltico são ruins e as sensibilidades ao aumento nos tempos de fluência e recuperação de 1 e 9 s para 2 e 18 s são elevadas. Ao ordenar os ligantes asfálticos do melhor para o pior à luz das propriedades e parâmetros considerados, o resultado é: CAP+Elvaloy+PPA, CAP+EVA, CAP+EVA+PPA, CAP+PPA, CAP+borracha+PPA, CAP+SBR+PPA, CAP+SBS+PPA, CAP+SBS, CAP+PE+PPA, CAP+borracha, CAP+SBR, CAP 50/70 e CAP+PE. / The multiple stress creep and recovery (MSCR) test is the result of a refinement of the repeated creep and recovery test (RCRT). This refinement was performed by the United States Federal Highway Administration (FHWA) with the aim of evaluating the percent recovery, the non-recoverable compliance and the stress dependency of asphalt binders, especially the modified ones. The MSCR test was applied in this study in order to characterize the creep-recovery behavior of unaged and short-term aged modified asphalt binders. The test procedure prescribed in ASTM D7405 specification was adopted and, to evaluate the influence of a greater creep-recovery time in the behavior of asphalt binders, the creep and recovery times of 2 and 18 s were also adopted in additional tests. The results of these tests, as well as the penetration, softening point, rotational viscosity, retained penetration, softening point increase, viscosity increase and mass loss data and mixing and compaction temperatures, were used with the objectives of ranking the asphalt binders and checking the ones with the best results in the parameters and properties considered. By using a PG 64-XX base asphalt-binder of 50/70 penetration grade, the following PG 76-XX odified asphalt binders were prepared: AC+PPA, AC+Elvaloy+PPA, AC+crumb rubber, AC+crumb rubber+PPA, AC+SBS, AC+SBS+PPA, AC+EVA, AC+EVA+PPA, AC+PE, AC+PE+PPA, AC+SBR and AC+SBR+PPA. In general, AC+Elvaloy+PPA has the best results in the parameters and properties considered in this study, especially due to the good results in the percent recovery and non-recoverable compliance and the lower stress sensitivity. In general, AC+PE has the worst results among the asphalt binders considered in this work, due to the facts that the percent recovery and non-recoverable compliance results are not good and the sensitivities to the creep-recovery times are high. By taking the results of this study and ranking the asphalt binders from the best to the worst, the following sequence is obtained: AC+Elvaloy+PPA, AC+EVA, AC+EVA+PPA, AC+PPA, AC+crumb rubber+PPA, AC+SBR+PPA, AC+SBS+PPA, AC+SBS, AC+PE+PPA, AC+crumb rubber, AC+SBR, neat AC and AC+PE.
50

An investigation into twentieth century flute trios with special reference to representative works by Goossens, Sil'vansky, Raphael, Damase, Marx and Crumb

Heunis, Daniela January 1994 (has links)
This thesis ventures into the world of twentieth century chamber music, specifically the trios written for flute, cello and piano. The first chapter discusses the history of the trio, tracing its development from the trio sonata of the Baroque Period to the accompanied sonatas and specifically the sonatas with flute and cello obbligato. Following the unpopularity of the genre throughout the Romantic period, its greater prominence in the Twentieth century is discussed, mentioning specific groups through whom the repertoire has been extended. Forty trios are grouped according to compositional styles. Six trios, each representing an example of a specific style period, have been selected for more detailed discussion, with particular reference to the various ways in which a sense of unity is achieved in each trio. The English composer Eugene Goossens uses impressionistic images, whole tone and chromatic scale patterns and other motifs to unify his trio: "Five Impressions of a Holiday". Nikolay Iosifovich Sil'vansky's "The Hedgehog and the Nightingale" is based on a Russian tale by Juri Jarmicha and uses a narrator. The three characters are represented by specific motivic and / or thematic material which is used throughout the trio. Günter Raphael's Trio-Suite op 44 is the only cyclic work unifying the two outer movements, without repeating any additional motivic material. Jean-Michel Damase condenses some of the material introduced in the opening Prelude in both the two Largo's and the two Arias in his "Sonate en Concert" of 1950. Karl Julius Marx builds his entire "Trio op 61" on a flexible six-note motif. Various movements in the trio" Vox Ba1aenae" by the American George Crumb are 1inked through the use of motives and characteristic instrumental colour. A comprehensive list of 180 twentieth century trios has been compiled, including details of dedications, commissions and first performances. 163 composers from twenty countries, are represented.

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