980 resultados para rapakivi texture


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We investigated adaptive neural control of precision grip forces during object lifting. A model is presented that adjusts reactive and anticipatory grip forces to a level just above that needed to stabilize lifted objects in the hand. The model obeys priciples of cerebellar structure and function by using slip sensations as error signals to adapt phasic motor commands to tonic force generators associated with output synergies controlling grip aperture. The learned phasic commands are weight and texture-dependent. Simulations of the new curcuit model reproduce key aspects of experimental observations of force application. Over learning trials, the onset of grip force buildup comes to lead the load force buildup, and the rate-of-rise of grip force, but not load force, scales inversely with the friction of the gripped object.

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How do humans rapidly recognize a scene? How can neural models capture this biological competence to achieve state-of-the-art scene classification? The ARTSCENE neural system classifies natural scene photographs by using multiple spatial scales to efficiently accumulate evidence for gist and texture. ARTSCENE embodies a coarse-to-fine Texture Size Ranking Principle whereby spatial attention processes multiple scales of scenic information, ranging from global gist to local properties of textures. The model can incrementally learn and predict scene identity by gist information alone and can improve performance through selective attention to scenic textures of progressively smaller size. ARTSCENE discriminates 4 landscape scene categories (coast, forest, mountain and countryside) with up to 91.58% correct on a test set, outperforms alternative models in the literature which use biologically implausible computations, and outperforms component systems that use either gist or texture information alone. Model simulations also show that adjacent textures form higher-order features that are also informative for scene recognition.

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When we look at a scene, how do we consciously see surfaces infused with lightness and color at the correct depths? Random Dot Stereograms (RDS) probe how binocular disparity between the two eyes can generate such conscious surface percepts. Dense RDS do so despite the fact that they include multiple false binocular matches. Sparse stereograms do so even across large contrast-free regions with no binocular matches. Stereograms that define occluding and occluded surfaces lead to surface percepts wherein partially occluded textured surfaces are completed behind occluding textured surfaces at a spatial scale much larger than that of the texture elements themselves. Earlier models suggest how the brain detects binocular disparity, but not how RDS generate conscious percepts of 3D surfaces. A neural model predicts how the layered circuits of visual cortex generate these 3D surface percepts using interactions between visual boundary and surface representations that obey complementary computational rules.

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An analysis of the reset of visual cortical circuits responsible for the binding or segmentation of visual features into coherent visual forms yields a model that explains properties of visual persistence. The reset mechanisms prevent massive smearing or visual percepts in response to rapidly moving images. The model simulates relationships among psychophysical data showing inverse relations of persistence to flash luminance and duration, greaterr persistence of illusory contours than real contours, a U-shaped temporal function for persistence of illusory contours, a reduction of persistence: due to adaptation with a stimulus of like orientation, an increase or persistence due to adaptation with a stimulus of perpendicular orientation, and an increase of persistence with spatial separation of a masking stimulus. The model suggests that a combination of habituative, opponent, and endstopping mechanisms prevent smearing and limit persistence. Earlier work with the model has analyzed data about boundary formation, texture segregation, shape-from-shading, and figure-ground separation. Thus, several types of data support each model mechanism and new predictions are made.

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This study has considered the optimisation of granola breakfast cereal manufacturing processes by wet granulation and pneumatic conveying. Granola is an aggregated food product used as a breakfast cereal and in cereal bars. Processing of granola involves mixing the dry ingredients (typically oats, nuts, etc.) followed by the addition of a binder which can contain honey, water and/or oil. In this work, the design and operation of two parallel wet granulation processes to produce aggregate granola products were incorporated: a) a high shear mixing granulation process followed by drying/toasting in an oven. b) a continuous fluidised bed followed by drying/toasting in an oven. In high shear granulation the influence of process parameters on key granule aggregate quality attributes such as granule size distribution and textural properties of granola were investigated. The experimental results show that the impeller rotational speed is the single most important process parameter which influences granola physical and textural properties. After that binder addition rate and wet massing time also show significant impacts on granule properties. Increasing the impeller speed and wet massing time increases the median granule size while also presenting a positive correlation with density. The combination of high impeller speed and low binder addition rate resulted in granules with the highest levels of hardness and crispness. In the fluidised bed granulation process the effect of nozzle air pressure and binder spray rate on key aggregate quality attributes were studied. The experimental results show that a decrease in nozzle air pressure leads to larger in mean granule size. The combination of lowest nozzle air pressure and lowest binder spray rate results in granules with the highest levels of hardness and crispness. Overall, the high shear granulation process led to larger, denser, less porous and stronger (less likely to break) aggregates than the fluidised bed process. The study also examined the particle breakage of granola during pneumatic conveying produced by both the high shear granulation and the fluidised bed granulation process. Products were pneumatically conveyed in a purpose built conveying rig designed to mimic product conveying and packaging. Three different conveying rig configurations were employed; a straight pipe, a rig consisting two 45° bends and one with 90° bend. Particle breakage increases with applied pressure drop, and a 90° bend pipe results in more attrition for all conveying velocities relative to other pipe geometry. Additionally for the granules produced in the high shear granulator; those produced at the highest impeller speed, while being the largest also have the lowest levels of proportional breakage while smaller granules produced at the lowest impeller speed have the highest levels of breakage. This effect clearly shows the importance of shear history (during granule production) on breakage during subsequent processing. In terms of the fluidised bed granulation, there was no single operating parameter that was deemed to have a significant effect on breakage during subsequent conveying. Finally, a simple power law breakage model based on process input parameters was developed for both manufacturing processes. It was found suitable for predicting the breakage of granola breakfast cereal at various applied air velocities using a number of pipe configurations, taking into account shear histories.

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Increased plasmin and plasminogen levels and elevated somatic cell counts (SCC) and polymorphonuclear leucocyte levels (PMN) were evident in late lactation milk. Compositional changes in these milks were associated with increased SCC. The quality of late lactation milks was related to nutritional status of herds, with milks from herds on a high plane of nutrition having composition and clotting properties similar to, or superior to, early-mid lactation milks. Nutritionally-deficient cows had elevated numbers of polymorphonuclear leucocytes (PMNs) in their milk, elevated plasmin levels and increased overall proteolytic activity. The dominant effect of plasmin on proteolysis in milks of low SCC was established. When present in elevated numbers, somatic cells and PMNs in particular had a more significant influence on the proteolysis of both raw and pasteurised milks than plasmin. PMN protease action on the caseins showed proteolysis products of two specific enzymes, cathepsin B and elastase, which were also shown in high SCC milk. Crude extracts of somatic cells had a high specificity on αs1-casein. Cheeses made from late lactation milks had increased breakdown of αs1-casein, suggestive of the action of somatic cell proteinases, which may be linked to textural defects in cheese. Late lactation cheeses also showed decreased production of small peptides and amino acids, the reason for which is unknown. Plasmin, which is elevated in activity in late lactation milk, accelerated the ripening of Gouda-type cheese, but was not associated with defects of texture or flavour. The retention of somatic cell enzymes in cheese curd was confirmed, and a potential role in production of bitter peptides identified. Cheeses made from milks containing high levels of PMNs had accelerated αs1-casein breakdown relative to cheeses made from low PMN milk of the same total SCC, consistent with the demonstrated action of PMN proteinases. The two types of cheese were determined significantly different by blind triangle testing.

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The application of sourdough can improve texture, structure, nutritional value, staling rate and shelf life of wheat and gluten-free breads. These quality improvements are associated with the formation of organic acids, exopolysaccharides (EPS), aroma or antifungal compounds. Initially, the suitability of two lactic acid bacteria strains to serve as sourdough starters for buckwheat, oat, quinoa, sorghum and flours was investigated. Wheat flour was chosen as a reference. The obligate heterofermentative lactic acid bacterium (LAB) Weissella cibaria MG1 (Wc) formed the EPS dextran (a α-1,6-glucan) from sucrose in situ with a molecular size of 106 to 107 kDa. EPS formation in all breads was analysed using size exclusion chromatography and highest amounts were formed in buckwheat (4 g/ kg) and quinoa sourdough (3 g/ kg). The facultative heterofermentative Lactobacillus plantarum FST1.7 (Lp) was identified as strong acidifier and was chosen due to its ubiquitous presence in gluten-free as well as wheat sourdoughs (Vogelmann et al. 2009). Both Wc and Lp, showed highest total titratable acids in buckwheat (16.8 ml; 26.0 ml), teff (16.2 ml; 24.5 ml) and quinoa sourdoughs (26.4 ml; 35.3 ml) correlating with higher amounts of fermentable sugars and higher buffering capacities. Sourdough incorporation reduced the crumb hardness after five days of storage in buckwheat (Wc -111%), teff (Wc -39%) and wheat (Wc -206%; Lp -118%) sourdough breads. The rate of staling (N/ day) was reduced in buckwheat (Ctrl 8 N; Wc 3 N; Lp 6 N), teff (Ctrl 13 N; Wc 9 N; Lp 10 N) and wheat (Ctrl 5 N; Wc 1 N; Lp 2 N) sourdough breads. Bread dough softening upon Wc and Lp sourdough incorporation accounted for increased crumb porosity in buckwheat (+10.4%; +4.7), teff (+8.1%; +8.3%) and wheat sourdough breads (+8.7%; +6.4%). Weissella cibaria MG1 sourdough improved the aroma quality of wheat bread but had no impact on aroma of gluten-free breads. Microbial shelf life however, was not prolonged in any of the breads regardless of the starter culture used. Due to the high prevalence of insulin-dependent diabetes mellitus particular amongst coeliac patients, glycaemic control is of great (Berti et al. 2004). The in vitro starch digestibility of gluten-free breads with and without sourdough addition was analysed to predict the GI (pGI). Sourdough can decrease starch hydrolysis in vitro, due to formation of resistant starch and organic acids. Predicted GI of gluten-free control breads were significantly lower than for the reference white wheat bread (GI=100). Starch granule size was investigated with scanning electron microscopy and was significantly smaller in quinoa flour (<2 μm). This resulted in higher enzymatic susceptibility and hence higher pGI for quinoa bread (95). Lowest hydrolysis indexes for sorghum and teff control breads (72 and 74, respectively) correlate with higher gelatinisation peak temperatures (69°C and 71°C, respectively). Levels of resistant starch were not increased by addition of Weissella cibaria MG1 (weak acidifier) or Lactobacillus plantarum FST1.7 (strong acidifier). The pGI was significantly decreased for both wheat sourdough breads (Wc 85; Lp 76). Lactic acid can promote starch interactions with gluten hence decreasing starch susceptibility (Östman et al. 2002). For most gluten-free breads, the pGI was increased upon sourdough addition. Only sorghum and teff Lp sourdough breads (69 and 68, respectively) had significantly decreased pGI. Results suggest that the increase of starch hydrolysis in gluten-free breads was related to mechanism other than presence of organic acids and formation of resistant starch.

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One problem in most three-dimensional (3D) scalar data visualization techniques is that they often overlook to depict uncertainty that comes with the 3D scalar data and thus fail to faithfully present the 3D scalar data and have risks which may mislead users’ interpretations, conclusions or even decisions. Therefore this thesis focuses on the study of uncertainty visualization in 3D scalar data and we seek to create better uncertainty visualization techniques, as well as to find out the advantages/disadvantages of those state-of-the-art uncertainty visualization techniques. To do this, we address three specific hypotheses: (1) the proposed Texture uncertainty visualization technique enables users to better identify scalar/error data, and provides reduced visual overload and more appropriate brightness than four state-of-the-art uncertainty visualization techniques, as demonstrated using a perceptual effectiveness user study. (2) The proposed Linked Views and Interactive Specification (LVIS) uncertainty visualization technique enables users to better search max/min scalar and error data than four state-of-the-art uncertainty visualization techniques, as demonstrated using a perceptual effectiveness user study. (3) The proposed Probabilistic Query uncertainty visualization technique, in comparison to traditional Direct Volume Rendering (DVR) methods, enables radiologists/physicians to better identify possible alternative renderings relevant to a diagnosis and the classification probabilities associated to the materials appeared on these renderings; this leads to improved decision support for diagnosis, as demonstrated in the domain of medical imaging. For each hypothesis, we test it by following/implementing a unified framework that consists of three main steps: the first main step is uncertainty data modeling, which clearly defines and generates certainty types of uncertainty associated to given 3D scalar data. The second main step is uncertainty visualization, which transforms the 3D scalar data and their associated uncertainty generated from the first main step into two-dimensional (2D) images for insight, interpretation or communication. The third main step is evaluation, which transforms the 2D images generated from the second main step into quantitative scores according to specific user tasks, and statistically analyzes the scores. As a result, the quality of each uncertainty visualization technique is determined.

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Flavour release from food is determined by the binding of flavours to other food ingredients and the partition of flavour molecules among different phases. Food emulsions are used as delivery systems for food flavours, and tailored structuring in emulsions provides novel means to better control flavour release. The current study investigated four structured oil-in-water emulsions with structuring in the oil phase, oil-water interface, and water phase. Oil phase structuring was achieved by the formation of monoglyceride (MG) liquid crystals in the oil droplets (MG structured emulsions). Structured interface was created by the adsorption of a whey protein isolate (WPI)-pectin double layer at the interface (multilayer emulsion). Water phase structured emulsions referred to emulsion filled protein gels (EFP gels), where emulsion droplets were embedded in WPI gel network, and emulsions with maltodextrins (MDs) of different dextrose-equivalent (DE) values. Flavour compounds with different physicochemical properties were added into the emulsions, and flavour release (release rate, headspace concentration and air-emulsion partition coefficient) was described by GC headspace analysis. Emulsion structures, including crystalline structure, particle size, emulsion stability, rheology, texture, and microstructures, were characterized using differential scanning calorimetry and X-ray diffraction, light scattering, multisample analytical centrifuge, rheometry, texture analysis, and confocal laser scanning microscopy, respectively. In MG structured emulsions, MG self-assembled into liquid crystalline structures and stable β-form crystals were formed after 3 days of storage at 25 °C. The inclusion of MG crystals allowed tween 20 stabilized emulsions to present viscoelastic properties, and it made WPI stabilized emulsions more sensitive to the change of pH and NaCl concentrations. Flavour compounds in MG structured emulsions had lower initial headspace concentration and air-emulsion partition coefficients than those in unstructured emulsions. Flavour release can be modulated by changing MG content, oil content and oil type. WPI-pectin multilayer emulsions were stable at pH 5.0, 4.0, and 3.0, but they presented extensive creaming when subjected to salt solutions with NaCl ≥ 150 mM and mixed with artificial salivas. Increase of pH from 5.0 to 7.0 resulted in higher headspace concentration but unchanged release rate, and increase of NaCl concentration led to increased headspace concentration and release rate. The study also showed that salivas could trigger higher release of hydrophobic flavours and lower release of hydrophilic flavours. In EFP gels, increases in protein content and oil content contributed to gels with higher storage modulus and force at breaking. Flavour compounds had significantly reduced release rates and air-emulsion partition coefficients in the gels than the corresponding ungelled emulsions, and the reduction was in line with the increase of protein content. Gels with stronger gel network but lower oil content were prepared, and lower or unaffected release rates of the flavours were observed. In emulsions containing maltodextrins, water was frozen at a much lower temperature, and emulsion stability was greatly improved when subjected to freeze-thawing. Among different MDs, MD DE 6 offered the emulsion the highest stability. Flavours had lower air-emulsion partition coefficients in the emulsions with MDs than those in the emulsion without MD. Moreover, the involvement of MDs in the emulsions allowed most flavours had similar release profiles before and after freeze-thaw treatment. The present study provided information about different structured emulsions as delivery systems for flavour compounds, and on how food structure can be designed to modulate flavour release, which could be helpful in the development of functional foods with improved flavour profile.

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Gabriel Urbain Fauré lived during one of the most exciting times in music history. Spanning a life of 79 years (1845-1924), he lived through the height of Romanticism and the experimental avant-garde techniques of the early 20th century. In Fauré's music, one can find traces of Chopin, Liszt, Mendelssohn, Debussy and Poulenc. One can even argue that Fauré presages Skryabin and Shostakovich. The late works of Gabriel Fauré, chiefly those composed after 1892, testify to the argument that Fauré holds an important position in the shift from tonal to atonal composition and should be counted among such transitional composers as Gustav Mahler, Claude Debussy, Erik Satie, Richard Strauss, and Ferruccio Busoni. Fauré's unique way of fashioning harmonic impetus of almost purely linear means, resulting in a synthesis of harmonic and melodic devices, led me to craft the term mélodoharmonique. This term refers to a contrapuntally motivated technique of composition, particularly in a secondary layer of musical texture, in which a component of harmonic progression (i.e. arpeggiation, broken chord, etc.) is fused with linear motivic or thematic development. This dissertation seeks to bring to public attention through exploration in lecture and recital format, certain works of Gabriel Fauré, written after 1892. The repertoire will be selected from works for solo piano and piano in collaboration with violin, violoncello, and voice, which support the notion of Fauré as a modernist deserving larger recognition for his influence in the transition to atonal music. The recital repertoire includes the following--Song Cycles: La bonne chanson, opus 61; La chanson d'Ève, opus 95; Le jardin clos, opus 106; Mirages, opus 113; L'horizon chimérique, opus 118; Piano Works: Prelude in G minor opus 103, No. 3; Prelude in E minor opus 103, No. 9; Eleventh Nocturne, opus 104, No.1; Thirteenth Nocturne, opus 119; Chamber Works: Second Violin Sonata, opus 108; First Violoncello Sonata, opus 109; Second Violoncello Sonata, opus 117.

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The Interloping Beguiler is an nineteen-minute concerto in four movements for bass clarinet solo and orchestra. The title refers to the role of the solo instrument, which continually thrusts itself into the affairs of the orchestra, deceiving and diverting the members of the orchestra away from their task of performing a "serious" orchestral composition. The bass clarinet portrays a comical, cartoon-like character whose awkward, and sometimes goofy, interjections cause chaos. Attempts are made by various members of the orchestra, especially the horns, to regain control of the work, but the bass clarinet always succeeds in its distracting antics. By the final movement of the composition, the bass clarinet has propelled the work into a cartoon-like landscape of quickly changing textures, dissonant intervals, and overlapping themes. The first movement, Introduction, sets the serious tone of the music to follow, or so it would seem. The entrance of the bass clarinet immediately changes this texture with its out-of-rhythm alternations between high and low pitches. This gesture provides a glimpse into the personality of the bass clarinet, an instrument here to mislead the members of the orchestra. Deception truly begins in the second movement, The Interloping Initiates. The bass clarinet starts the movement with a driving theme and is immediately supported by the orchestra. As the movement progresses, the bass clarinet quickly begins altering the theme, making it more playful and cartoonish. A struggle ensues between the horns and the bass clarinet, with the bass clarinet catapulting the piece into a latin-inspired section. The struggle continues through to the end of the movement. The third movement, Calm, is exactly what the title suggests. A sectional form distinguishes this movement from the second movement. Throughout Calm, the bass clarinet behaves with decorum, except for very large melodic leaps. The seed of anarchy planted by the bass clarinet in the second movement comes to fruition in the final movement, The Beguiling Builds. Here, the bass clarinet sends the work into chaos with sections recalling Looney Tunes cartoons, Hollywood western music, and children's folk songs.

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This dissertation project focuses on J.S. Bach's Six Suites and explores the ideology of the Suites as etudes versus concert pieces. It is my belief that the evolution of the rank of the Suites in a cellist's repertoire today represents more than just historical coincidence. My premise is that the true genius of the Suites lies in their dual role as !&I efficient teaching pieces and superior performance works. Consequently, the maximum use of Bach's Six Suites as pedagogical material heightens both technical ability and deeper appreciation of the art. The dual nature of the Suites must always be emphasized: not only do these pieces provide innumerable opportunities for building cello technique, but they also offer material for learning the fundamentals of melody, harmony, dynamics, phrasing and texture. It is widely accepted among academic musicians that Bach's keyboard music serves as perfect compositions -- the model for music theory, music form and music counterpoint. I argue that we should employ the Cello Suites to this same end. The order in which the Suites are presented was deliberately chosen to highlight the contrasts in the pieces. Because the technical demands of each suite grow progressively from the previous one, they were performed non-consecutively in order to balance the difficulty and depth of each recital. The first compact disc consists of the Third Suite in C Major and Fifth Suite in C minor (with scordatura tuning), emphasizing the parallel keys. The Second Suite in D Minor and the Fourth Suite in E-flat Major comprises the compact disc. Finally, in the third compact disc, the First Suite in G Major and the Sixth Suite in D Major (composed for the five string cello piccola, but played here on a four-string cello) highlights the progression of the Suites.

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This piece explores the changing nature of emotion focusing especially on the feeling of sorrow. The opening and ending parts of the first movement represent the overall motive of sorrow. The first movement opens with an augmented chord G-C#-F-B and from this chord the first violin expands upwards while the cello moves downwards towards the C chord (p.2). As the melody alternates between each part, there is a subtle change in harmony which creates tension and release and changes the sound color. In addition, ornamentation in each part reinforces the movement towards the C chord. This progression represents the inner emotion of lament. Sostenuto e largamente section (p.2) uses heterophony in order to express a feeling of chaos. Section Scherzando (p.4) uses the interval relationship M7 and m2, and is a respite from the overwhelming feeling of sorrow. The ending of the first movement (p.12) returns to create a second tension by every instrument ascending slowly, and the viola produces a distinctive melody derived from the previous chaotic section that ends on an Ab. The second movement contrasts with the first movement in order to express a concealed, not explicit, sorrow, and differs in both tempo and texture. The tempo is a waltz that is faster than the first movement. This produces a light, playful figure and a simple melody without much ornamentation. Imitation and canonic structure emphasize the individuality of the strings. The third movement merges material from the first movement rhythmic figure and the second movement pizzicato (p.17). It shows timbral change through con sordino, pizzicato arpeggio, and sul ponticello to display string techniques. An Allegro section (p.19) especially contrasts with Misterioso in rhythm and dynamics. In the Grazioso (p.22), random beats are accentuated by pizzicato arpeggio to de-emphasize the meter. Finally, there is a return to the ending figure of the first movement with con sordino (p.23) and sul ponticello in viola that articulates the internal tension and the timbral change to return to a voice of sorrow.

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The variation and fugue originated from the 15th and 16th centuries and blossomed during the Baroque and Classical Periods. In a variation, a theme with a particular structure precedes a series of pieces that usually have the same or very similar structure. A fugue is a work written in imitative counterpoint in which the theme is stated successively in all voices of polyphonic texture. Beethoven’s use of variation and fugue in large scale works greatly influenced his contemporaries. After the Classical Period, variations continued to be popular, and numerous composers employed the technique in various musical genres. Fugues had pedagogical associations, and by the middle of 19th century became a requirement in conservatory instruction, modeled after Bach’s Well-Tempered Clavier. In the 20th century, the fugue was revived in the spirit of neoclassicism; it was incorporated in sonatas, and sets of preludes and fugues were composed. Schubert's Wanderer Fantasy presents his song Der Wanderer through thematic transformations, including a fugue and a set of variations. Liszt was highly influenced by this, as shown in his thematic transformations and the fugue as one of the transformations in his Sonata in b. In Schumann’s Symphonic Études, Rachmaninoff's Rhapsody on a Theme of Paganini and Copland’s Piano Variations, the variation serves as the basis for the entire work. Prokofiev and Schubert take a different approach in Piano Concerto No. 3 and Wanderer Fantasy, employing the variation in a single movement. Unlike Schubert and Liszt's use of the fugue as a part of the piece or movement, Franck’s Prelude Chorale et Fugue and Shchedrin’s Polyphonic Notebook use it in its independent form. Since the Classical Period, the variation and fugue have evolved from stylistic and technical influences of earlier composers. It is interesting and remarkable to observe the unique effects each had on a particular work. As true and dependable classic forms, they remain popular by offering the composer an organizational framework for musical imagination.

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Unlike some other major composer-pianists (Franz Liszt and Alexander Scriabin being the most notable examples), Sergei Rachmaninov did not experience any dramatic changes in his compositional style; one can, however, notice certain stylistic differences between piano works composed during different periods of his long creative life. This dissertation argues that a clear evolution of Rachmaninov's pianistic style through his three creative periods can be traced by examining a selection of his compositions, from his first significant cycle for piano, 5 Marceaux de fantaisie, Op. 3 (1892), all the way through to his last piano work, a transcription of P.I.Tchakovsky's Lullaby, Op. 16, No. 1 (1941). Rachmaninov's life as a composer can be divided into three periods. His early period was ended abruptly by the disastrous premiere ofhis First Symphony in 1897, which caused a deep psychological crisis in the life of the young composer. Piano works of this period are often characterized by relatively simple homophonic texture, when Rachmaninov was clearly influenced by some of his Russian predecessors, most notably Tchaikovsky. His second and most productive period, also known as the period of"Russian maturity," started in 1900, when he began working on the Second Suite for two pianos, Op. 17, and the Second Concerto, Op. 18; this phase ended with the Russian Bolshevik revolution of 1917. Works of this time exhibit a mature style of piano writing, with rich, virtuosic - often considered excessive by many critics - texture and ever-increasing use of chromatic harmonies. Rachmaninov's works of the third period are limited in number owing to the composer's preoccupation with a career as pianist. Original works for piano now give way to revisions of earlier compositions and transcriptions: Rachmaninov's piano writing becomes more efficient and economical without losing any of its virtuosic brilliance. This dissertation project examines in detail, over the course of three piano recitals, a variety of works composed during the "Russian maturity" period, from several Preludes from Op. 23 (1903), the first major cycle for solo piano of the period, to 9 Etudes-Tableaux, Op.39 (1917), the last one; the early period is represented by 3 of 5 Marceaux defantaisie, Op. 3 (1892), while the late period is shown through several piano transcriptions and revised versions of the remaining 2 pieces from Op. 3.