438 resultados para winding drum
Resumo:
The present data compilation includes ciliates growth rate, grazing rate and gross growth efficiency determined either in the field or in laboratory experiments. From the existing literature, we synthesized all data that we could find on cilliate. Some sources might be missing but none were purposefully ignored. Field data on microzooplankton grazing are mostly comprised of grazing rate using the dilution technique with a 24h incubation period. Laboratory grazing and growth data are focused on pelagic ciliates and heterotrophic dinoflagellates. The experiment measured grazing or growth as a function of prey concentration or at saturating prey concentration (maximal grazing rate). When considering every single data point available (each measured rate for a defined predator-prey pair and a certain prey concentration) there is a total of 1485 data points for the ciliates, counting experiments that measured growth and grazing simultaneously as 1 data point.
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This dissertation consists of three distinct components: (1) “Double Rainbow,” a notated composition for an acoustic ensemble of 10 instruments, ca. 36 minutes. (2) “Appalachiana”, a fixed-media composition for electro-acoustic music and video, ca. 30 minutes, and (3) “'The Invisible Mass': Exploring Compositional Technique in Alfred Schnittke’s Second Symphony”, an analytical article.
(1) Double Rainbow is a ca. 36 minute composition in four movements scored for 10 instruments: flute, Bb clarinet (doubling on bass clarinet), tenor saxophone (doubling on alto saxophone), french horn, percussion (glockenspiel, vibraphone, wood block, 3 toms, snare drum, bass drum, suspended cymbal), piano, violin, viola, cello, and double bass. Each of the four movements of the piece explore their own distinct character and set of compositional goals. The piece is presented as a musical score and as a recording, which was extensively treated in post-production.
(2) Appalachiana, is a ca. 30 minute fixed-media composition for music and video. The musical component was created as a vehicle to showcase several approaches to electro-acoustic music composition –fft re-synthesis for time manipulation effects, the use of a custom-built software instrument which implements generative approaches to creating rhythm and pitch patterns, using a recording of rain to create rhythmic triggers for software instruments, and recording additional components with acoustic instruments. The video component transforms footage of natural landscapes filmed at several locations in North Carolina, Virginia, and West Virginia into a surreal narrative using a variety of color, lighting, distortion, and time-manipulation video effects.
(3) “‘The Invisible Mass:’ Exploring Compositional Technique in Alfred Schnittke’s Second Symphony” is an analytical article that focuses on Alfred Schnittke’s compositional technique as evidenced in the construction of his Second Symphony and discussed by the composer in a number of previously untranslated articles and interviews. Though this symphony is pivotal in the composer’s oeuvre, there are currently no scholarly articles that offer in-depth analyses of the piece. The article combines analyses of the harmony, form, and orchestration in the Second Symphony with relevant quotations from the composer, some from published and translated sources and others newly translated by the author from research at the Russian State Library in St. Petersburg. These offer a perspective on how Schnittke’s compositional technique combines systematic geometric design with keen musical intuition.
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The effects of temperature and food availability on feeding and egg production of the Arctic copepod Calanus hyperboreus were investigated in Disko Bay, western Greenland, from winter to spring 2009. The abundance of females in the near bottom layer and the egg production of C. hyperboreus prior to the spring bloom document that reproduction relies on lipid stores. The maximum in situ egg production (± SE) of 54 ± 8 eggs female/d was recorded in mid-February at chlorophyll a concentrations below 0.1 µg/l, whereas no egg production was observed in mid-April when the spring bloom developed. After reproduction, the females migrated to the surface layer to exploit the bloom and refill their lipid stores. In 2 laboratory experiments, initiated before and during the spring bloom, mature females were kept with and without food at 5 different temperatures ranging from 0 to 10°C and the fecal pellet and egg production were monitored. Food had a clear effect on fecal pellet production but no effect on egg production, while temperature did not have an effect on egg or fecal pellet production in any of the experiments. Analyses of carbon and lipid content of the females before and after the experiments did not reflect any effect of food or temperature in the pre-bloom experiment, whereas in the bloom experiment a clear positive effect of food was detected in female biochemical profiles. The lack of a temperature response suggests a future warmer ocean could be unfavorable for C. hyperboreus compared to smaller Calanus spp. which are reported to exploit minor temperature elevations for increased egg production.
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This study describes differences in plankton community structure and in chemical and physical gradients between the offshore West Greenland Current system and inland regions close to the Greenland Ice Sheet during the post-bloom in Godthabsfjorden (64° N, 51° W). The offshore region had pronounced vertical mixing, with centric diatoms and Phaeocystis spp. dominating the phytoplankton, chlorophyll (chl) a (0.3 to 3.9 µg/l) was evenly distributed and nutrients were depleted in the upper 50 m. Ciliates and heterotrophic dinoflagellates constituted equal parts of the protozooplankton biomass. Copepod biomass was dominated by Calanus spp. Primary production, copepod production and the vertical flux were high offshore. The water column was stratified in the fjord, causing chl a to be concentrated in a thin sub-surface layer. Nutrients were depleted above the pycnocline, and Thalassiosira spp. dominated the phytoplankton assemblage close to the ice sheet. Dinoflagellates dominated the protozooplankton biomass, whereas copepod biomass was low and was dominated by Pseudocalanus spp. and Metridia longa. Primary production was low in the outer part of the fjord but considerably higher in the inner parts of the fjord. Copepod production was exceeded by protozooplankton production in the fjord. The results of both physical/chemical factors and biological parameters suggest separation of offshore and fjord systems.
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As part of the ultrafast charge dynamics initiated by high intensity laser irradiations of solid targets,high amplitude EM pulses propagate away from the interaction point and are transported along anystalks and wires attached to the target. The propagation of these high amplitude pulses along a thinwire connected to a laser irradiated target was diagnosed via the proton radiography technique,measuring a pulse duration of 20 ps and a pulse velocity close to the speed of light. The strongelectric field associated with the EM pulse can be exploited for controlling dynamically the protonbeams produced from a laser-driven source. Chromatic divergence control of broadband laser drivenprotons (upto 75% reduction in divergence of >5 MeV protons) was obtained by winding the supportingwire around the proton beam axis to create a helical coil structure. In addition to providingfocussing and energy selection, the technique has the potential to post-accelerate the transiting protonsby the longitudinal component of the curved electric field lines produced by the helical coil lens.
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We study the nonequilibrium dynamics of the linear to zigzag structural phase transition exhibited by an ion chain confined in a trap with periodic boundary conditions. The transition is driven by reducing the transverse confinement at a finite quench rate, which can be accurately controlled. This results in the formation of zigzag domains oriented along different transverse planes. The twists between different domains can be stabilized by the topology of the trap and under laser cooling the system has a chance to relax to a helical chain with nonzero winding number. Molecular dynamics simulations are used to obtain a large sample of possible trajectories for different quench rates. The scaling of the average winding number with different quench rates is compared to the prediction of the Kibble-Zurek theory, and a good quantitative agreement is found.
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La frontière entre le politique et l'intellectualisme militant est, d'ordinaire, ténue. Tout univers politico-constitutionnel est ainsi susceptible de faire les frais d'un martèlement doctrinal qui, à maints égards, relève davantage du construit que du donné. Résultante directe d'une construction parfois intéressée, le récit identitaire, à force de répétition, s'installera confortablement sur les sièges de l'imaginaire populaire. Il accèdera, au fil du temps, au statut de mythe pur et simple. Ce dernier, politiquement parlant, revêt de puissants effets aphrodisiaques. La présente thèse doctorale s'intéresse plus particulièrement aux mythes créés, depuis 1982, par un segment de la doctrine québécoise : en matière de droits linguistiques, objet principal de notre étude, Charte canadienne des droits et libertés et Cour suprême, toutes deux liguées contre le Québec, combineront leurs efforts afin d'assurer le recul du fait français dans la Belle Province. Quant aux francophones hors Québec, ceux-ci, depuis l'effritement du concept de nation canadienne-française, sont dorénavant exclus de l'équation, expurgés de l'échiquier constitutionnel. En fait, l'adoption d'un nationalisme méthodologique comme nouvelle orthodoxie politique et doctrinale rend ardue, en plusieurs sens, la conciliation de leur existence avec les paradigmes et épistémologie maintenant consacrés. Ainsi, et selon la logique du tiers exclu, une victoire francophone hors Québec signifiera, du fait d'une prétendue symétrie interprétative, un gain pour la communauté anglo-québécoise. Cette thèse vise à discuter de la teneur de diverses allégories établies et, le cas échéant, à reconsidérer la portée réelle de la Charte canadienne en matière linguistique. Il sera alors démontré que plusieurs lieux communs formulés par les milieux intellectuels québécois échouent au moins partiellement, le test de l'analyse factuelle. Celui-ci certifiera de l'exclusion, par la doxa, de toute décision judiciaire ou autre vérité empirique ne pouvant cadrer à même les paramètres, voire les prismes, de l'orthodoxie suggérée.
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In this dissertation, I demonstrate how improvisations within the structures of performance during Montserrat’s annual festivals produce “rhythms of change” that contribute to the formation of cultural identities. Montserrat is a small island of 39.5 square miles in the Caribbean’s Leeward Islands, and a volcanic disaster in the 1990s led to the loss of villages, homes, and material possessions. The crisis resulted in mass displacement and emigration, and today’s remaining population of 5,000 is now in a stage of post-volcano redevelopment. The reliability of written archives for establishing cultural knowledge is tenuous, and the community is faced with re-energizing cherished cultural traditions. This ethnographic research traces my embodied search for Montserrat’s history through an archive that is itself intangible and performative. Festivals produce some of the island’s most visible and culturally political events, and music and dance performances prompt on- and off-stage discussions about the island’s multifaceted heritage. The festival cycle provides the structure for ongoing renegotiations of what it means to be “Montserratian.” I focus especially on the island’s often-discussed and debated “triangular” heritage of Irishness, Africanness, and Montserratianness as it is performed during the festivals. Through my meanderings along the winding hilly roads of Montserrat, I explored reconfigurations of cultural memory through the island’s masquerade dance tradition and other festival celebrations. In this work, I introduce a “Cast of Characters,” each of whose scholarly, artistic, and public service work on Montserrat contributes to the shape and transformation of the island’s post-volcano cultural identities today. This dissertation is about the kinesthetic transmission of shared (and sometimes unshared) cultural knowledge, the substance of which echoes in the rhythms of Montserrat’s music and dance practices today.
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French Impressionism is a term which is often used in discussing music originating in France towards the end of the nineteenth century. The term Spanish Impressionism could also be used when discussing Spanish music written by the Spanish composers who studied and worked in Paris at the same time as their French counterparts. After all, Spanish music written during this time exhibits many of the same characteristics and aesthetics as French music of the same era. This dissertation will focus on the French and Spanish composers writing during that exciting time. Musical impressionism emphasizes harmonic effects and rhythmic fluidity in the pursuit of evocative moods, sound pictures of nature or places over the formalism of structure and thematic concerns. The music of this time is highly virtuosic as well as musically demanding, since many of the composers were brilliant pianists. My three dissertation recitals concentrated on works which exhibited the many facets of impressionism as well as the technical and musical challenges. The repertoire included selections by Spanish composers Manuel de Falla, Isaac Albéniz, Enrique Granados, Joaquín Turina, and Joaquín Rodrigo and French composers Claude Debussy and Maurice Ravel. The recitals were on April 30, 2013, February 23, 2014 and October 11, 2015. They included solo piano works by Granados and Albéniz, vocal works by Debussy, Ravel, de Falla, Turina and Rodrigo, piano trios by Granados and Turina, instrumental duos by Debussy, Ravel and de Falla, and a two-piano work of Debussy transcribed by Ravel. All three recitals were held in Gildenhorn Recital Hall at the University of Maryland and copies of this dissertation and recordings of each recital may be found through the Digital Repository at the University of Maryland (DRUM).
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The role of the double bass in Vienna during the eighteenth century evolved significantly between 1760 and 1812. During these years, Viennese composers began to view the double bass less as an accompanimental instrument and more as a solo voice. Despite the abundance of music written for the double bass during this time, few of these compositions are regularly performed today. This dissertation serves three purposes. I explore how learning eighteenth-century Viennese compositions in the original tuning can influence modern performances of these works. Secondly, I document the arrangement of a lesser-know work for the modern tuned bass using the manuscript as the source material. Finally, by performing a variety of eighteenth-century bass works, I bring this music to the public's attention. The research for this dissertation has been presented in two forms. The recitals present both solo and chamber works from eighteenth-century Vienna. The repertoire for the three recitals was chosen so that each recital addresses one of the three purposes mentioned above. The research paper presents performance practices of the eighteenth century, challenges the modern double bassist faces when playing this literature, as well as a look into how to arrange one of these works for the modern tuned double bass. The three recitals were performed on the campus of the University of Maryland in the Leah M. Smith Hall, Gildenhorn Recital Hall and the Ulrich Recital Hall, respectively. Recordings of all three recitals can be found in the Digital Repository at the University of Maryland (DRUM).
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A cor da superfície dos alimentos é o primeiro parâmetro de qualidade avaliado pelos consumidores, e é critico para a aceitação do produto, então a medição adequada da cor é uma importante ferramenta. Nesta pesquisa avaliou-se a variação da cor em corvina (Micropogonias furnieri) armazenada em gelo durante 16 dias; os parâmetros de luminosidade (L*), valor cromático a*, valor cromático b*, variação total da cor (ΔE) e croma (C*) foram obtidos por sistema de visão computacional, e por colorímetro Konica Minolta CR-400. O frescor da corvina baseada nas mudanças da cor das brânquias foi avaliado utilizando um sistema de visão computacional. Também se modelou a oxidação da mioglobina em files de burriquete (Pogonias cromis), utilizando os parâmetros de vermelho (valor a* e R). Para registrar as mudanças da cor durante 57,6 h utilizou-se um sistema de visão computacional, a análise química realizou-se determinando a concentração de metamioglobina (%). Na avaliação da cor de corvina armazenada em gelo, o sistema de visão computacional mostrou diferenças significativas para L*, a*, ΔE e C*, enquanto que o colorímetro mostrou diferenças significativas para L* e ΔE, o único parâmetro que não apresentou diferenças entre instrumentos foi ΔE durante a avaliação da corvina armazenada em gelo. O coeficiente de correlação entre os parâmetros da cor (L*, a* e b*) das brânquias da corvina armazenada em gelo pelo tempo de armazenamento foi de 0,9747. O sistema de visão computacional registrou as mudanças da cor em filés de burriquete e se modelaram as mudanças utilizando um modelo exponencial. O sistema de visão computacional mostrou ser mais sensível às mudanças da cor durante a avaliação da cor na corvina armazenada em gelo. É possível prognosticar o tempo de armazenamento da corvina em gelo em função da mudança da cor das brânquias. Assim, foi possível modelar a variação da mioglobina em filés de burriquete utilizando sistemas de visão computacional para registrar ditas mudanças. Os sistemas de visão computacional têm grande capacidade para registrar as mudanças da cor e é possível utiliza-los para avaliar os alimentos em função da cor.
Resumo:
Every year in the US and other cold-climate countries considerable amount of money is spent to restore structural damages in conventional bridges resulting from (or “caused by”) salt corrosion in bridge expansion joints. Frequent usage of deicing salt in conventional bridges with expansion joints results in corrosion and other damages to the expansion joints, steel girders, stiffeners, concrete rebar, and any structural steel members in the abutments. The best way to prevent these damages is to eliminate the expansion joints at the abutment and elsewhere and make the entire bridge abutment and deck a continuous monolithic structural system. This type of bridge is called Integral Abutment Bridge which is now widely used in the US and other cold-climate countries. In order to provide lateral flexibility, the entire abutment is constructed on piles. Piles used in integral abutments should have enough capacity in the perpendicular direction to support the vertical forces. In addition, piles should be able to withstand corrosive environments near the surface of the ground and maintain their performance during the lifespan of the bridge. Fiber Reinforced Polymer (FRP) piles are a new type of pile that can not only accommodate large displacements, but can also resist corrosion significantly better than traditional steel or concrete piles. The use of FRP piles extends the life of the pile which in turn extends the life of the bridge. This dissertation studies FRP piles with elliptical shapes. The elliptical shapes can simultaneously provide flexibility and stiffness in two perpendicular axes. The elliptical shapes can be made using the filament winding method which is a less expensive method of manufacturing compared to the pultrusion or other manufacturing methods. In this dissertation a new way is introduced to construct the desired elliptical shapes with the filament winding method. Pile specifications such as dimensions, number of layers, fiber orientation angles, material, and soil stiffness are defined as parameters and the effects of each parameter on the pile stresses and pile failure have been studied. The ANSYS software has been used to model the composite materials. More than 14,000 nonlinear finite element pile models have been created, each slightly different from the others. The outputs of analyses have been used to draw curves. Optimum values of the parameters have been defined using generated curves. The best approaches to find optimum shape, angle of fibers and types of composite material have been discussed.
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My dissertation presented seven violin concertos in three recital programs. Three of these concertos are acknowledged masterpieces performed in established concert venues throughout the world. They are the concertos of Mozart, Beethoven and Tchaikovsky. The other four are less standard and are composed by Viotti, Kreutzer, Rode and Spohr. These less standard concertos were popular during their time yet they seem not to have stood the test of time. A curriculum devoted exclusively to the standard concertos creates problems for the young violinist. The Mozart violin concertos are often the first standard concertos that the young violin student encounters. They are considered to be the least technically demanding of the standard concertos. The next most advanced standard concertos that the student will usually encounter are Bruch’s G minor concerto, Wieniawski’s D minor concerto and Barber’s concerto. The trouble is that the work on Mozart concertos does not adequately prepare a student for the next most advanced standard concerto. There is a discontinuous leap in the progression of technical difficulty between the Mozart concertos and the next most advanced concertos. Likewise the standard concerto repertoire provides no smooth historical or stylistic progression between the Mozart concertos and the next most advanced concertos. If the young violinist is limited to the standard repertoire then she has no smooth progression either technical, historical or stylistic. I seek to demonstrate that, by adding concertos of Spohr, Viotti, Kreutzer, and Rode to the standard violin curriculum, one could remedy this problem. The first and third recitals were performed in the Gildenhorn Recital Hall and the second recital in the School of Music’s Smith Lecture Hall, both at the University of Maryland. All three recitals can be found in the Digital Repository at the University of Maryland (DRUM).
Resumo:
Chamber music with piano comprises some of the greatest masterpieces in the Western canon. The works range from duo sonatas with various instruments through septets. In regard to duo sonatas, the violin is the instrument most frequently paired with the piano. Of all the chamber works for larger ensembles, the most popular is the quintet. In this dissertation, I will be exploring the similarities and differences between the duo sonatas and quintets of a given composer. I will be surveying Robert Schumann’s Piano Quintet in E-flat Major, Op. 44 along with his Violin and Piano Sonata in A Minor, Op. 105. The next pairing will be Johannes Brahms’ Piano Quintet in F Minor, Op. 34 and his Piano and Violin Sonata in D Minor, Op. 108. Dmitri Shostakovich’s Piano Quintet in G Minor, Op. 57 and his Cello and Piano Sonata in D Minor, Op. 40 will be the last two works examined in this dissertation. This dissertation project consisted of three recitals, presented in the Gildenhorn Recital Hall at the Clarice Smith Performing Arts Center of the University of Maryland. The recitals featured works by Johannes Brahms, Robert Schumann and Dmitri Shostakovich and took place on March 14, 2014, February 13, 2015 and November 22, 2015. All three recitals were recorded on compact discs, which can be accessed at the Digital Repository at the University of Maryland (DRUM) and at the University of Maryland Hornbake Library.