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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.
141

Heimferðin (The Journey Home): Tone Poem for Symphony Orchestra

Ingimundardottir, Gudrun January 2009 (has links)
Composers of the 20th century express through intimate and personal language the conditions of the present, utilizing compositional techniques, forms, pitch and rhythmic language, and characteristics of Western composers, as well as looking towards non- Western music for the same. Each musical language, be it tonal, twelve-tone, modal, pitch-class, or derived from folk and non-Western material, is contained in a structural framework which is audibly recognizable, and controls the musical tapestry, processes, and results. Frequently composers use distinctive musical languages to portray different atmospheres, and thus allow each musical language to dominate the texture in order to create the desired contrast. But, jumping directly from one pitch language to another can create a sense of cacophony and loss of cohesion to the composition as a whole. In my composition I intend to show that by superimposing the structural parameters of one musical language onto another, it is possible to attain consistency and coherence, despite the underlying diversity. The composition is based on the story Heimferðin (The Journey Home) by Sigurður Rúnar Þrastarson (1961-1998). The composition is in five movements: I. Dawn; II. Dance and Devotion; III. Frolic; IV. Fury, V. Farwell. Each movement describes particular settings and events of the story. Internal events have been slightly reordered, but otherwise the composition follows the storyline from beginning to end. The final two minutes and twenty seconds of the composition are an original arrangement of a song, written in 1820, by the Danish composer P. C. Krossing (1793-1838).
142

Score-level fusion for multimodal biometrics

Alsaade, Fawaz January 2008 (has links)
This thesis describes research into the score-level fusion process in multimodal biometrics. The emphasis of the research is on the fusion of face and voice biometrics in the two recognition modes of verification and open-set identification. The growing interest in the use of multiple modalities in biometrics is due to its potential capabilities for eradicating certain important limitations of unimodal biometrics. One of the factors important to the accuracy of a multimodal biometric system is the choice of the technique deployed for data fusion. To address this issue, investigations are carried out into the relative performance of several statistical data fusion techniques for combining the score information in both unimodal and multimodal biometrics (i.e. speaker and/ or face verification). Another important issue associated with any multimodal technique is that of variations in the biometric data. Such variations are reflected in the corresponding biometric scores, and can thereby adversely influence the overall effectiveness of multimodal biometric recognition. To address this problem, different methods are proposed and investigated. The first approach is based on estimating the relative quality aspects of the test scores and then passing them on into the fusion process either as features or weights. The approach provides the possibility of tackling the data variations based on adjusting the weights for each of the modalities involved according to its relative quality. Another approach considered for tackling the effects of data variations is based on the use of score normalisation mechanisms. Whilst score normalisation has been widely used in voice biometrics, its effectiveness in other biometrics has not been previously investigated. This method is shown to considerably improve the accuracy of multimodal biometrics by appropriately correcting the scores from degraded modalities prior to the fusion process. The investigations in this work are also extended to the combination of score normalisation with relative quality estimation. The experimental results show that, such a combination is more effective than the use of only one of these techniques with the fusion process. The thesis presents a thorough description of the research undertaken, details the experimental results and provides a comprehensive analysis of them.
143

Voice biometrics under mismatched noise conditions

Pillay, Surosh Govindasamy January 2011 (has links)
This thesis describes research into effective voice biometrics (speaker recognition) under mismatched noise conditions. Over the last two decades, this class of biometrics has been the subject of considerable research due to its various applications in such areas as telephone banking, remote access control and surveillance. One of the main challenges associated with the deployment of voice biometrics in practice is that of undesired variations in speech characteristics caused by environmental noise. Such variations can in turn lead to a mismatch between the corresponding test and reference material from the same speaker. This is found to adversely affect the performance of speaker recognition in terms of accuracy. To address the above problem, a novel approach is introduced and investigated. The proposed method is based on minimising the noise mismatch between reference speaker models and the given test utterance, and involves a new form of Test-Normalisation (T-Norm) for further enhancing matching scores under the aforementioned adverse operating conditions. Through experimental investigations, based on the two main classes of speaker recognition (i.e. verification/ open-set identification), it is shown that the proposed approach can significantly improve the performance accuracy under mismatched noise conditions. In order to further improve the recognition accuracy in severe mismatch conditions, an approach to enhancing the above stated method is proposed. This, which involves providing a closer adjustment of the reference speaker models to the noise condition in the test utterance, is shown to considerably increase the accuracy in extreme cases of noisy test data. Moreover, to tackle the computational burden associated with the use of the enhanced approach with open-set identification, an efficient algorithm for its realisation in this context is introduced and evaluated. The thesis presents a detailed description of the research undertaken, describes the experimental investigations and provides a thorough analysis of the outcomes.
144

The visualization and representation of electroacoustic music

Gray, David January 2013 (has links)
In Chapters 1 and 2 there are definitions and a review of electroacoustic music, and then visualization generally and as applied to music. Chapter 3 is a review of specific and relevant literature as regards to the visualization of electroacoustic music. Chapter 4 introduces the concepts of imagining as opposed to discovering new sound, and what is important to this research about these terms; in addition what is meant and indicated by them. Chapter 5 deals with the responses that composers currently working have made to the enquiry concerning visualization. In this chapter these responses are dealt with as case studies. In a similar way, Chapter 6 looks at some examples of historical work in electroacoustic music, again as case studies. In Chapter 7 a taxonomical structure for the use of visualization in electroacoustic composition is established and derived from the case study results. Chapter 8 looks at relevant examples of software and how they offer visualization case studies. Chapter 9 looks at the place of the archive in various stages of the compositional process. Chapter 10 investigates the problems of visualizing musical timbre as possible evidence for future strategies. Chapter 11 offers some conclusions and implications as to the main research questions, as well as more specific outlines of potential strategies for the visualization of electroacoustic music.
145

The role of genetics in regulation of weight loss and food intake

Bandstein, Marcus January 2016 (has links)
While obesity is a world leading health problem, the most efficient treatment option for severely obese patients is Roux-Y gastric bypass (RYGB) surgery. However, there are large inter-individual differences in weight loss after RYGB surgery. The reasons for this are not yet elucidated and the role of genetics in weight loss-regulation is still not fully understood. The main aim for this thesis was to investigate the effects of common obesity-associated genetic variants and their effect on weight loss and food intake. We examined if the weight loss two years following RYGB surgery depends on the  FTO genotype, as well as pre-surgery vitamin D status. For FTO AA-carriers, the surgery resulted in a 3% per-allele increased excess BMI loss (EBMIL; P=0.02). When split by vitamin D baseline status, the EBMIL of vitamin D deficient patients carrying AA exceeded that of vitamin D deficient patients carrying TT by 14% (P=0.03). No such genotypic differences were found in patients without pre-surgery vitamin D deficiency. As the influence of individual single nucleotide polymorphisms may be small, we identified a novel method to combine SNPs into a genetic risk score (GRS). Using the random forest model, SNPs with high impact on weight loss after RYGB surgery were filtered out. An up to 11% lower EBMIL with higher risk score was estimated for the GRS model (p=0.026) composed of seven BMI-associated SNPs (closest genes: MC4R, TMEM160, PTBP2, NUDT3, TFAP2B, ZNF608 and MAP2K5). Pre-surgical hunger feelings were found to be associated with EBMIL and the SNP rs4846567. Before surgery, patients filled out the Three Factor Eating Questionnaire and were genotyped for known BMI and waist-hip ratio (WHR) associated SNPs. Patients with the lowest hunger scores had up to 32% greater EBMIL compared to the highest scoring patients (P=0.002). TT-allele carriers of rs4846567 showed a 58% lower hunger feelings. TT- carriers also showed a 51% decrease in disinhibition, but no significant impact on cognitive restraint was observed. Due to the association of eating behaviour and weight loss, acute effects on DNA methylation in response to a food intake intervention of a standardized meal were also investigated. After food intake, 1832 CpG sites were differentially methylated compared to the baseline after multiple testing correction. When adjusted for white blood cell fractions, 541 CpG sites remained. This may be interpreted as that the immune system is playing an active role in the response to food intake and highlights the dynamic nature of DNA-methylation. These findings will contribute to a better care for morbidly obese patients. Post-surgical treatment may be optimized so that patients with a less favourable genetic profile may receive additional support for weight loss and weight management. This may be considered as a step in the transition towards personalized medicine.
146

Region of Interest Aware and Impairment Based Image Quality Assessment

Chandu, Chiranjeevi January 2016 (has links)
No description available.
147

The impact of family composition on adult earnings

Skog, Frida January 2016 (has links)
This thesis addresses to what extent childhood family composition – the number of siblings and whether the parents live together, or whether there are non-parental adults and/or half-siblings in the household or not – contributes to variations in adult earnings. The theoretical perspective suggests that resources mediate the effect. While research has shown that siblings, as well as divorce and remarriage, are negatively linked to child outcomes, there are inconsistencies in previous literature. There has been debate over the unconfoundedness of previous studies, something that is handled here by analyzing large sets of representative data using a robust parameter. The longitudinal dataset used is based on Swedish administrative data and the cohorts analyzed are born in the beginning of the 1970s. The data structure is well suited for the assumptions underlying the semi-parametric method propensity score matching. The findings show that family size impacts on adult earnings. However, this is not always of concern. For example, no effect of siblings is found in affluent families, and if siblings are closely spaced this results in better outcomes for children. Divorce and remarriage do not seem to lower the future earnings of children. Thus, this thesis shows that some of the most well-established patterns in the sociology of the family, namely the link between number of siblings and adult earnings, and between divorce/family re-formation and adult earnings, can be broken by resources.
148

User-centred video abstraction

Darabi, Kaveh January 2015 (has links)
The rapid growth of digital video content in recent years has imposed the need for the development of technologies with the capability to produce condensed but semantically rich versions of the input video stream in an effective manner. Consequently, the topic of Video Summarisation is becoming increasingly popular in multimedia community and numerous video abstraction approaches have been proposed accordingly. These recommended techniques can be divided into two major categories of automatic and semi-automatic in accordance with the required level of human intervention in summarisation process. The fully-automated methods mainly adopt the low-level visual, aural and textual features alongside the mathematical and statistical algorithms in furtherance to extract the most significant segments of original video. However, the effectiveness of this type of techniques is restricted by a number of factors such as domain-dependency, computational expenses and the inability to understand the semantics of videos from low-level features. The second category of techniques however, attempts to alleviate the quality of summaries by involving humans in the abstraction process to bridge the semantic gap. Nonetheless, a single user’s subjectivity and other external contributing factors such as distraction will potentially deteriorate the performance of this group of approaches. Accordingly, in this thesis we have focused on the development of three user-centred effective video summarisation techniques that could be applied to different video categories and generate satisfactory results. According to our first proposed approach, a novel mechanism for a user-centred video summarisation has been presented for the scenarios in which multiple actors are employed in the video summarisation process in order to minimise the negative effects of sole user adoption. Based on our recommended algorithm, the video frames were initially scored by a group of video annotators ‘on the fly’. This was followed by averaging these assigned scores in order to generate a singular saliency score for each video frame and, finally, the highest scored video frames alongside the corresponding audio and textual contents were extracted to be included into the final summary. The effectiveness of our approach has been assessed by comparing the video summaries generated based on our approach against the results obtained from three existing automatic summarisation tools that adopt different modalities for abstraction purposes. The experimental results indicated that our proposed method is capable of delivering remarkable outcomes in terms of Overall Satisfaction and Precision with an acceptable Recall rate, indicating the usefulness of involving user input in the video summarisation process. In an attempt to provide a better user experience, we have proposed our personalised video summarisation method with an ability to customise the generated summaries in accordance with the viewers’ preferences. Accordingly, the end-user’s priority levels towards different video scenes were captured and utilised for updating the average scores previously assigned by the video annotators. Finally, our earlier proposed summarisation method was adopted to extract the most significant audio-visual content of the video. Experimental results indicated the capability of this approach to deliver superior outcomes compared with our previously proposed method and the three other automatic summarisation tools. Finally, we have attempted to reduce the required level of audience involvement for personalisation purposes by proposing a new method for producing personalised video summaries. Accordingly, SIFT visual features were adopted to identify the video scenes’ semantic categories. Fusing this retrieved data with pre-built users’ profiles, personalised video abstracts can be created. Experimental results showed the effectiveness of this method in delivering superior outcomes comparing to our previously recommended algorithm and the three other automatic summarisation techniques.
149

Trabecular Bone Microarchitecture in Association with Systemic and Local Factors as Potential Predictors of Implant Failure

Camacho, Diego A., DMD 01 January 2016 (has links)
Clinicians have described the success rates of dental implants. The use of implants is projected to increase in the future. With a 5-10% failure rate, it is unclear the exact factors that are associated with implant failures. To improve upon these success rates, it is critical to understand parameters associated with implant failure including: periodontitis, peri-implantitis, systemic diseases, site preparation, dental history of the implant site, bone quality, materials, occlusion, and treatment timelines. While bone quality is associated with failure, objective measures to assess bone quality and characteristics are scarce. Therefore, the aim of this study is to determine whether possible comorbidities, associated dental parameters, and measurable bone quality are possible predictors of implant failure. In this study, we utilized the electronic health record system axiUm® to retrospectively investigate non-failed (NF) and failed (F) dental implants from a patient cohort with 149 implants placed between 2012-2015 at Virginia Commonwealth University School of Dentistry. A chart review was conducted extracting information on age, gender, systemic diseases, smoking, occlusal trauma, parafunction, bone grafting history, treatment timelines, implant site/type/placement protocol, infection, torque at placement, bone quality and microarchitecture assessed by the novel, innovative technology: trabecular bone score (TBS). A total of 149 implants, 46 failures and 105 non-failed controls, were selected based on similar implant sites. Preliminary data obtained from analysis suggests that average time from implant placement to failure was 6.6 months (0.55 years). Parafunction habit (p=0.0202) and increased number of implants (p=0.0478) were found to be associated with increased implant failure.
150

Características Clínicas- Epidemiológicas en pacientes con cirrosis hepática en el Hospital Central de la Fuerza Aérea del Perú durante el periodo 2013- 2016

Matos Santiváñez, Stephany Paola January 2017 (has links)
INTRODUCCIÓN: La cirrosis es una causa creciente de morbilidad y mortalidad en los países más desarrollados, siendo la 14ª causa de muerte más frecuente en todo el mundo pero la cuarta en Europa central. Cada vez más, se ha visto que la cirrosis no es una sola entidad de enfermedad, pero que puede subclasificarse en distintas etapas clínicas de pronóstico, con un año de mortalidad que oscila entre el 1% y el 57% dependiendo del estadío. OBJETIVO: Determinar las características clínicas y epidemiológicas en pacientes con el diagnóstico de cirrosis hepática en el Hospital Central de la Fuerza Aérea del Perú. MÉTODOS: Estudio observacional, descriptivo, retrospectivo y transversal. Se tomó todo el universo de historias clínicas comprendidas entre el período mencionado, las cuales incluyeron 72 historias clínicas de pacientes con Cirrosis Hepática. Se analizaron los datos con el software SPSS Statistics 19, se consideró las medias y desviación estándar para las variables numéricas y frecuencia y porcentajes para las variables categóricas. RESULTADOS: El 59.72% fueron mujeres; la media de la edad global fue 74.85 +/- 14.1 años. La etiología más frecuente de Cirrosis Hepática fue la Cirrosis Biliar Primaria (26.39%) y en segundo lugar la ingesta de alcohol (18.06%). El 61.11% tuvo alguna hospitalización previa, siendo las infecciones (45.45%) la causa más frecuente de hospitalización, seguida de la ascitis (18.18%), encefalopatía (15.91%) y HDA (13.64%). La infección de mayor frecuencia fue la infección del tracto urinario (75%). Cuando se evaluó el score de Child- Pugh el 51.39% se encontró en estadío A y según el score de MELD, la severidad de la enfermedad hepática se encontró que el 45.83% tenía un puntaje entre 10-18 puntos. Las comorbilidades más frecuentes que presentó la población fue: HTA (59.72%) y DM2 (41.67%). CONCLUSIONES: Las características clínicas- epidemiológicas de los pacientes con Cirrosis Hepática en el Hospital Central de la Fuerza Aérea del Perú, en una población de 72 pacientes, mostro una gran heterogeneidad epidemiológica, etiológica y clínica.

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