882 resultados para automatic music analysis


Relevância:

30.00% 30.00%

Publicador:

Resumo:

This study examined the properties of ERP effects elicited by unattended (spatially uncued) objects using a short-lag repetition-priming paradigm. Same or different common objects were presented in a yoked prime-probe trial either as intact images or slightly scrambled (half-split) versions. Behaviourally, only objects in a familiar (intact) view showed priming. An enhanced negativity was observed at parietal and occipito-parietal electrode sites within the time window of the posterior N250 after the repetition of intact, but not split, images. An additional post-hoc N2pc analysis of the prime display supported that this result could not be attributed to differences in salience between familiar intact and split views. These results demonstrate that spatially unattended objects undergo visual processing but only if shown in familiar views, indicating a role of holistic processing of objects that is independent of attention.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Les courriels Spams (courriels indésirables ou pourriels) imposent des coûts annuels extrêmement lourds en termes de temps, d’espace de stockage et d’argent aux utilisateurs privés et aux entreprises. Afin de lutter efficacement contre le problème des spams, il ne suffit pas d’arrêter les messages de spam qui sont livrés à la boîte de réception de l’utilisateur. Il est obligatoire, soit d’essayer de trouver et de persécuter les spammeurs qui, généralement, se cachent derrière des réseaux complexes de dispositifs infectés, ou d’analyser le comportement des spammeurs afin de trouver des stratégies de défense appropriées. Cependant, une telle tâche est difficile en raison des techniques de camouflage, ce qui nécessite une analyse manuelle des spams corrélés pour trouver les spammeurs. Pour faciliter une telle analyse, qui doit être effectuée sur de grandes quantités des courriels non classés, nous proposons une méthodologie de regroupement catégorique, nommé CCTree, permettant de diviser un grand volume de spams en des campagnes, et ce, en se basant sur leur similarité structurale. Nous montrons l’efficacité et l’efficience de notre algorithme de clustering proposé par plusieurs expériences. Ensuite, une approche d’auto-apprentissage est proposée pour étiqueter les campagnes de spam en se basant sur le but des spammeur, par exemple, phishing. Les campagnes de spam marquées sont utilisées afin de former un classificateur, qui peut être appliqué dans la classification des nouveaux courriels de spam. En outre, les campagnes marquées, avec un ensemble de quatre autres critères de classement, sont ordonnées selon les priorités des enquêteurs. Finalement, une structure basée sur le semiring est proposée pour la représentation abstraite de CCTree. Le schéma abstrait de CCTree, nommé CCTree terme, est appliqué pour formaliser la parallélisation du CCTree. Grâce à un certain nombre d’analyses mathématiques et de résultats expérimentaux, nous montrons l’efficience et l’efficacité du cadre proposé.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The work presented in this thesis is concerned with the dynamical behavior of a CBandola's acoustical box at low resonances -- Two models consisting of two and three coupled oscillators are proposed in order to analyse the response at the first two and three resonances, respectively -- These models describe the first resonances in a bandola as a combination of the lowest modes of vibration of enclosed air, top and back plates -- Physically, the coupling between these elements is caused by the fluid-structure interaction that gives rise to coupled modes of vibration for the assembled resonance box -- In this sense, the coupling in the models is expressed in terms of the ratio of effective areas and masses of the elements which is an useful parameter to control the coupling -- Numerical models are developed for the analysis of modal coupling which is performed using the Finite Element Method -- First, it is analysed the modal behavior of separate elements: enclosed air, top plate and back plate -- This step is important to identify participating modes in the coupling -- Then, a numerical model of the resonance box is used to compute the coupled modes -- The computation of normal modes of vibration was executed in the frequency range of 0-800Hz -- Although the introduced models of coupled oscillators only predict maximum the first three resonances, they also allow to study qualitatively the coupling between the rest of the computed modes in the range -- Considering that dynamic response of a structure can be described in terms of the modal parameters, this work represents, in a good approach, the basic behavior of a CBandola, although experimental measurements are suggested as further work to verify the obtained results and get more information about some characteristics of the coupled modes, for instance, the phase of vibration of the air mode and the radiation e ciency

Relevância:

30.00% 30.00%

Publicador:

Resumo:

With the world of professional sports shifting towards employing better sport analytics, the demand for vision-based performance analysis is growing increasingly in recent years. In addition, the nature of many sports does not allow the use of any kind of sensors or other wearable markers attached to players for monitoring their performances during competitions. This provides a potential application of systematic observations such as tracking information of the players to help coaches to develop their visual skills and perceptual awareness needed to make decisions about team strategy or training plans. My PhD project is part of a bigger ongoing project between sport scientists and computer scientists involving also industry partners and sports organisations. The overall idea is to investigate the contribution technology can make to the analysis of sports performance on the example of team sports such as rugby, football or hockey. A particular focus is on vision-based tracking, so that information about the location and dynamics of the players can be gained without any additional sensors on the players. To start with, prior approaches on visual tracking are extensively reviewed and analysed. In this thesis, methods to deal with the difficulties in visual tracking to handle the target appearance changes caused by intrinsic (e.g. pose variation) and extrinsic factors, such as occlusion, are proposed. This analysis highlights the importance of the proposed visual tracking algorithms, which reflect these challenges and suggest robust and accurate frameworks to estimate the target state in a complex tracking scenario such as a sports scene, thereby facilitating the tracking process. Next, a framework for continuously tracking multiple targets is proposed. Compared to single target tracking, multi-target tracking such as tracking the players on a sports field, poses additional difficulties, namely data association, which needs to be addressed. Here, the aim is to locate all targets of interest, inferring their trajectories and deciding which observation corresponds to which target trajectory is. In this thesis, an efficient framework is proposed to handle this particular problem, especially in sport scenes, where the players of the same team tend to look similar and exhibit complex interactions and unpredictable movements resulting in matching ambiguity between the players. The presented approach is also evaluated on different sports datasets and shows promising results. Finally, information from the proposed tracking system is utilised as the basic input for further higher level performance analysis such as tactics and team formations, which can help coaches to design a better training plan. Due to the continuous nature of many team sports (e.g. soccer, hockey), it is not straightforward to infer the high-level team behaviours, such as players’ interaction. The proposed framework relies on two distinct levels of performance analysis: low-level performance analysis, such as identifying players positions on the play field, as well as a high-level analysis, where the aim is to estimate the density of player locations or detecting their possible interaction group. The related experiments show the proposed approach can effectively explore this high-level information, which has many potential applications.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The use of human brain electroencephalography (EEG) signals for automatic person identi cation has been investigated for a decade. It has been found that the performance of an EEG-based person identication system highly depends on what feature to be extracted from multi-channel EEG signals. Linear methods such as Power Spectral Density and Autoregressive Model have been used to extract EEG features. However these methods assumed that EEG signals are stationary. In fact, EEG signals are complex, non-linear, non-stationary, and random in nature. In addition, other factors such as brain condition or human characteristics may have impacts on the performance, however these factors have not been investigated and evaluated in previous studies. It has been found in the literature that entropy is used to measure the randomness of non-linear time series data. Entropy is also used to measure the level of chaos of braincomputer interface systems. Therefore, this thesis proposes to study the role of entropy in non-linear analysis of EEG signals to discover new features for EEG-based person identi- cation. Five dierent entropy methods including Shannon Entropy, Approximate Entropy, Sample Entropy, Spectral Entropy, and Conditional Entropy have been proposed to extract entropy features that are used to evaluate the performance of EEG-based person identication systems and the impacts of epilepsy, alcohol, age and gender characteristics on these systems. Experiments were performed on the Australian EEG and Alcoholism datasets. Experimental results have shown that, in most cases, the proposed entropy features yield very fast person identication, yet with compatible accuracy because the feature dimension is low. In real life security operation, timely response is critical. The experimental results have also shown that epilepsy, alcohol, age and gender characteristics have impacts on the EEG-based person identication systems.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

We propose a study of the mathematical properties of voice as an audio signal -- This work includes signals in which the channel conditions are not ideal for emotion recognition -- Multiresolution analysis- discrete wavelet transform – was performed through the use of Daubechies Wavelet Family (Db1-Haar, Db6, Db8, Db10) allowing the decomposition of the initial audio signal into sets of coefficients on which a set of features was extracted and analyzed statistically in order to differentiate emotional states -- ANNs proved to be a system that allows an appropriate classification of such states -- This study shows that the extracted features using wavelet decomposition are enough to analyze and extract emotional content in audio signals presenting a high accuracy rate in classification of emotional states without the need to use other kinds of classical frequency-time features -- Accordingly, this paper seeks to characterize mathematically the six basic emotions in humans: boredom, disgust, happiness, anxiety, anger and sadness, also included the neutrality, for a total of seven states to identify

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Wordplay and the translation of wordplay is a complex subject that has been addressed by various studies. The combination of a single form and multiple meanings created by wordplay makes it challenging to translate. Translating wordplay has even been considered impossible. This thesis explores wordplay and the translation of wordplay through an analysis of wordplay found in an English novel and its Finnish translation. The purpose is to shed light on the problems and solutions found in the data. The study consists of a quantitative analysis and a subsequent discussion on the findings. The findings from the study indicate that cultural aspects such as idioms and allusions are especially problematic when it comes to translating wordplay. Also, the communicative functions of wordplay were found to be central for a successful translation. It is concluded that these aspects require further study.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

With the increasing complexity of today's software, the software development process is becoming highly time and resource consuming. The increasing number of software configurations, input parameters, usage scenarios, supporting platforms, external dependencies, and versions plays an important role in expanding the costs of maintaining and repairing unforeseeable software faults. To repair software faults, developers spend considerable time in identifying the scenarios leading to those faults and root-causing the problems. While software debugging remains largely manual, it is not the case with software testing and verification. The goal of this research is to improve the software development process in general, and software debugging process in particular, by devising techniques and methods for automated software debugging, which leverage the advances in automatic test case generation and replay. In this research, novel algorithms are devised to discover faulty execution paths in programs by utilizing already existing software test cases, which can be either automatically or manually generated. The execution traces, or alternatively, the sequence covers of the failing test cases are extracted. Afterwards, commonalities between these test case sequence covers are extracted, processed, analyzed, and then presented to the developers in the form of subsequences that may be causing the fault. The hypothesis is that code sequences that are shared between a number of faulty test cases for the same reason resemble the faulty execution path, and hence, the search space for the faulty execution path can be narrowed down by using a large number of test cases. To achieve this goal, an efficient algorithm is implemented for finding common subsequences among a set of code sequence covers. Optimization techniques are devised to generate shorter and more logical sequence covers, and to select subsequences with high likelihood of containing the root cause among the set of all possible common subsequences. A hybrid static/dynamic analysis approach is designed to trace back the common subsequences from the end to the root cause. A debugging tool is created to enable developers to use the approach, and integrate it with an existing Integrated Development Environment. The tool is also integrated with the environment's program editors so that developers can benefit from both the tool suggestions, and their source code counterparts. Finally, a comparison between the developed approach and the state-of-the-art techniques shows that developers need only to inspect a small number of lines in order to find the root cause of the fault. Furthermore, experimental evaluation shows that the algorithm optimizations lead to better results in terms of both the algorithm running time and the output subsequence length.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The Czech composer Petr Eben (1927-2007) has written music in all genres except symphony, but he is highly recognized for his organ and choral compositions, which are his preferred genres. His vocal works include choral songs and vocal-instrumental works at a wide range of difficulty levels, from simple pedagogical songs to very advanced and technically challenging compositions. This study examines two of Eben‘s vocal-instrumental compositions. The oratorio Apologia Sokratus (1967) is a three-movement work; its libretto is based on Plato‘s Apology of Socrates. The ballet Curses and Blessings (1983) has a libretto compiled from numerous texts from the thirteenth to the twentieth centuries. The formal design of the ballet is unusual—a three-movement composition where the first is choral, the second is orchestral, and the third combines the previous two played simultaneously. Eben assembled the libretti for both compositions and they both address the contrasting sides of the human soul, evil and good, and the everlasting fight between them. This unity and contrast is the philosophical foundation for both compositions. The dissertation discusses the multileveled meanings behind the text settings and musical style of the oratorio and ballet in analyses focusing on the text, melodic and harmonic construction, and symbolism. Additional brief analyses of other vocal and vocal-instrumental compositions by Eben establish the ground for the examination of the oratorio and ballet and for understanding features of the composer‘s musical style. While the oratorio Apologia Sokratus was discussed in short articles in the 1970s, the ballet Curses and Blessings has never previously been addressed within Eben scholarship. The dissertation examines the significant features of Eben‘s music. His melodic style incorporates influences as diverse as Gregorian chant and folk tunes on the one hand, and modern vocal techniques such as Sprechgesang and vocal aleatoricism on the other. His harmonic language includes bitonality and polytonality, used to augment the tonal legacy of earlier times, together with elements of pitch collections and limited serial procedures as well as various secundal and quartal harmonic sonorities derived from them. His music features the vibrant rhythms of folk music, and incorporates other folk devices like ostinato, repetitive patterns, and improvisation.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

We develop the a-posteriori error analysis of hp-version interior-penalty discontinuous Galerkin finite element methods for a class of second-order quasilinear elliptic partial differential equations. Computable upper and lower bounds on the error are derived in terms of a natural (mesh-dependent) energy norm. The bounds are explicit in the local mesh size and the local degree of the approximating polynomial. The performance of the proposed estimators within an automatic hp-adaptive refinement procedure is studied through numerical experiments.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

This paper provides an exploratory study of how rewards-based crowdfunding affects business model development for music industry artists, labels and live sector companies. The empirical methodology incorporated a qualitative, semi-structured, three-stage interview design with fifty seven senior executives from industry crowdfunding platforms and three stakeholder groups. The results and analysis cover new research ground and provide conceptual models to develop theoretical foundations for further research in this field. The findings indicate that the financial model benefits of crowdfunding for independent artists are dependent on fan base demographic variables relating to age group and genre due to sustained apprehension from younger audiences. Furthermore, major labels are now considering a more user-centric financial model as an innovation strategy, and the impact of crowdfunding on their marketing model may already be initiating its development in terms of creativity, strength and artist relations.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

At the dawn of the twentieth century, Imperial Russia was in the throes of immense social, political and cultural upheaval. The effects of rapid industrialization, rising capitalism and urbanization, as well as the trauma wrought by revolution and war, reverberated through all levels of society and every cultural sphere. In the aftermath of the 1905 revolution, amid a growing sense of panic over the chaos and divisions emerging in modern life, a portion of Russian educated society (obshchestvennost’) looked to the transformative and unifying power of music as a means of salvation from the personal, social and intellectual divisions of the contemporary world. Transcending professional divisions, these “orphans of Nietzsche” comprised a distinct aesthetic group within educated Russian society. While lacking a common political, religious or national outlook, these philosophers, poets, musicians and other educated members of the upper and middle strata were bound together by their shared image of music’s unifying power, itself built upon a synthesis of Russian and European ideas. They yearned for a “musical Orpheus,” a composer capable of restoring wholeness to society through his music. My dissertation is a study in what I call “musical metaphysics,” an examination of the creation, development, crisis and ultimate failure of this Orphic worldview. To begin, I examine the institutional foundations of musical life in late Imperial Russia, as well as the explosion of cultural life in the aftermath of the 1905 Revolution, a vibrant social context which nourished the formation of musical metaphysics. From here, I assess the intellectual basis upon which musical metaphysics rested: central concepts (music, life-transformation, theurgy, unity, genius, nation), as well as the philosophical heritage of Nietzsche and the Christian thinkers Vladimir Solov’ev, Aleksei Khomiakov, Ivan Kireevskii and Lev Tolstoi. Nietzsche’s orphans’ struggle to reconcile an amoral view of reality with a deeply felt sense of religious purpose gave rise to neo-Slavophile interpretations of history, in which the Russian nation (narod) was singled out as the savior of humanity from the materialism of modern life. This nationalizing tendency existed uneasily within the framework of the multi-ethnic empire. From broad social and cultural trends, I turn to detailed analysis of three of Moscow’s most admired contemporary composers, whose individual creative voices intersected with broader social concerns. The music of Aleksandr Scriabin (1871-1915) was associated with images of universal historical progress. Nikolai Medtner (1879-1951) embodied an “Imperial” worldview, in which musical style was imbued with an eternal significance which transcended the divisions of nation. The compositions of Sergei Rachmaninoff (1873-1943) were seen as the expression of a Russian “national” voice. Heightened nationalist sentiment and the impact of the Great War spelled the doom of this musical worldview. Music became an increasingly nationalized sphere within which earlier, Imperial definitions of belonging grew ever more problematic. As the Germanic heritage upon which their vision was partially based came under attack, Nietzsche’s orphans found themselves ever more divided and alienated from society as a whole. Music’s inability to physically transform the world ultimately came to symbolize the failure of Russia’s educated strata to effectively deal with the pressures of a modernizing society. In the aftermath of the 1917 revolutions, music was transformed from a symbol of active, unifying power into a space of memory, a means of commemorating, reinterpreting, and idealizing the lost world of Imperial Russia itself.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The production and perception of music is a multimodal activity involving auditory, visual and conceptual processing, integrating these with prior knowledge and environmental experience. Musicians utilise expressive physical nuances to highlight salient features of the score. The question arises within the literature as to whether performers’ non-technical, non-sound-producing movements may be communicatively meaningful and convey important structural information to audience members and co-performers. In the light of previous performance research (Vines et al., 2006, Wanderley, 2002, Davidson, 1993), and considering findings within co-speech gestural research and auditory and audio-visual neuroscience, this thesis examines the nature of those movements not directly necessary for the production of sound, and their particular influence on audience perception. Within the current research 3D performance analysis is conducted using the Vicon 12- camera system and Nexus data-processing software. Performance gestures are identified as repeated patterns of motion relating to music structure, which not only express phrasing and structural hierarchy but are consistently and accurately interpreted as such by a perceiving audience. Gestural characteristics are analysed across performers and performance style using two Chopin preludes selected for their diverse yet comparable structures (Opus 28:7 and 6). Effects on perceptual judgements of presentation modes (visual-only, auditory-only, audiovisual, full- and point-light) and viewing conditions are explored. This thesis argues that while performance style is highly idiosyncratic, piano performers reliably generate structural gestures through repeated patterns of upper-body movement. The shapes and locations of phrasing motions are identified particular to the sample of performers investigated. Findings demonstrate that despite the personalised nature of the gestures, performers use increased velocity of movements to emphasise musical structure and that observers accurately and consistently locate phrasing junctures where these patterns and variation in motion magnitude, shape and velocity occur. By viewing performance motions in polar (spherical) rather than cartesian coordinate space it is possible to get mathematically closer to the movement generated by each of the nine performers, revealing distinct patterns of motion relating to phrasing structures, regardless of intended performance style. These patterns are highly individualised both to each performer and performed piece. Instantaneous velocity analysis indicates a right-directed bias of performance motion variation at salient structural features within individual performances. Perceptual analyses demonstrate that audience members are able to accurately and effectively detect phrasing structure from performance motion alone. This ability persists even for degraded point-light performances, where all extraneous environmental information has been removed. The relative contributions of audio, visual and audiovisual judgements demonstrate that the visual component of a performance does positively impact on the over- all accuracy of phrasing judgements, indicating that receivers are most effective in their recognition of structural segmentations when they can both see and hear a performance. Observers appear to make use of a rapid online judgement heuristics, adjusting response processes quickly to adapt and perform accurately across multiple modes of presentation and performance style. In line with existent theories within the literature, it is proposed that this processing ability may be related to cognitive and perceptual interpretation of syntax within gestural communication during social interaction and speech. Findings of this research may have future impact on performance pedagogy, computational analysis and performance research, as well as potentially influencing future investigations of the cognitive aspects of musical and gestural understanding.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The present article reflects the progress of an ongoing master’s dissertation on language engineering. The main goal of the work here described, is to infer a programmer’s profile through the analysis of his source code. After such analysis the programmer shall be placed on a scale that characterizes him on his language abilities. There are several potential applications for such profiling, namely, the evaluation of a programmer’s skills and proficiency on a given language or the continuous evaluation of a student’s progress on a programming course. Throughout the course of this project and as a proof of concept, a tool that allows the automatic profiling of a Java programmer is under development. This tool is also introduced in the paper and its preliminary outcomes are discussed.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

When performing Particle Image Velocimetry (PIV) measurements in complex fluid flows with moving interfaces and a two-phase flow, it is necessary to develop a mask to remove non-physical measurements. This is the case when studying, for example, the complex bubble sweep-down phenomenon observed in oceanographic research vessels. Indeed, in such a configuration, the presence of an unsteady free surface, of a solid–liquid interface and of bubbles in the PIV frame, leads to generate numerous laser reflections and therefore spurious velocity vectors. In this note, an image masking process is developed to successively identify the boundaries of the ship and the free surface interface. As the presence of the solid hull surface induces laser reflections, the hull edge contours are simply detected in the first PIV frame and dynamically estimated for consecutive ones. As for the unsteady surface determination, a specific process is implemented like the following: i) the edge detection of the gradient magnitude in the PIV frame, ii) the extraction of the particles by filtering high-intensity large areas related to the bubbles and/or hull reflections, iii) the extraction of the rough region containing these particles and their reflections, iv) the removal of these reflections. The unsteady surface is finally obtained with a fifth-order polynomial interpolation. The resulted free surface is successfully validated from the Fourier analysis and by visualizing selected PIV images containing numerous spurious high intensity areas. This paper demonstrates how this data analysis process leads to PIV images database without reflections and an automatic detection of both the free surface and the rigid body. An application of this new mask is finally detailed, allowing a preliminary analysis of the hydrodynamic flow.