Made available in DSpace on 2014-06-12T18:02:43Z (GMT). No. of bitstreams: 2 arquivo4052_1.pdf: 1926198 bytes, checksum: a394edbf4f303fa7b25af920df83cf25 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2008 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Este trabalho propõe uma técnica não-paramétrica para detecção de bordas em imagens speckle. As imagens SAR ("Synthetic aperture Radar"), sonar, B-ultrasound e laser são corrompidas por um ruído não aditivo chamado speckle. Vários modelos estatísticos foram propostos para desrever este ruído, levando ao desenvolvimento de técnicas especiais para melhoramento e análise de imagens. A distribuição G0 é um modelo estatístico que consegue descrever uma ampla gama de áreas, como, por exemplo, em dados SAR, pastos (lisos), florestas (rugosos) e áreas urbanas (muito rugosos). O objetivo deste trabalho é estudar ténicas alternativas na detecção de imagens speckled, tomando como ponto de partida Gambini et al. (2006, 2008). Um novo detector de borda baseado no teste de Kruskal Wallis é proposto. Os nossos resultados numéricos mostram que esse detector é uma alternativa atraente ao detector de M. Gambini, que é baseado na função de verossimilhançaa. Neste trabalho fornecemos evidências de que a técnica de M. Gambini pode ser substituída om sucesso pelo método Kruskal Wallis. O ganho reside em ter um algoritmo 1000 vezes mais rápido, sem omprometer a qualidade dos resultados

Master of Science / Department of Biological & Agricultural Engineering / Ajay Sharda / Discovered in 1971, sudden death syndrome (SDS), caused by the fungus Fusarium virguliforme, has spread from the US to South American and European countries. It has potential to infect soybean crops worldwide, causing yield losses of 10% to 15% and even 70% in extreme cases. There is a need for rapid spatial assessment of SDS. Currently, the extent and severity of SDS are scored using visual symptoms as indicators. This method can take hours to collect and is subject to human bias and changing environmental conditions. Color infrared (CIR) and thermal infrared (TIR) imagery detect changes in light reflectance (visible and near-infrared bands) and emittance (canopy temperature), respectively. Stressed crops may show deviations in light reflectiveness, as well as elevated canopy temperatures. The use of CIR and TIR imagery and flexible aerial remote sensing platforms offer an alternative for SDS detection and diagnosis compared to hand scoring methods. Crop stress and diseases have been detected using manned and unmanned aerial systems previously. Yet, to date, SDS has not been remotely assessed using CIR or TIR imagery collected with aerial platforms. The following research utilizes high throughput CIR and TIR imagery collected using a small unmanned aerial system (sUAS) to detect and assess SDS. A comparative evaluation of ground-based and aerial CIR methods for assessing SDS was conducted to understand the effectiveness of novel aerial SDS detection methods. Furthermore, a TIR case study investigating the use of potential thermal canopy changes for SDS detection was conducted to investigate the possibility of using TIR as an SDS indicator. CIR reflectance measured from a ground-based spectrometer and sUAS was collected data over a two-year period. Ground-based spectrometer data were collected weekly, while a sUAS collected aerial imagery late in the growing season each year before plant maturity. Pigment index (PI) values were derived from ground-based and aerial data. Results showed a strong negative correlation between SDS score and PI values. Aerial and ground-based data both showed strong correlations to SDS score, however, aerial data displayed a stronger relationship possibly due to minimal changes in environmental conditions. High SDS scores correlated strongly to aerial derived PI (R2 = 0.8359). Rapidly assessed high SDS allows for accurate screening of SDS critical for soybean breeding. The second year of the study investigated each component of SDS score, severity, and incidence. PI proved to have the best correlation with severity (R2 = 0.6313 and ρ = -0.8016) rather than incidence or SDS score. PI also correlated to SDS scores with R2 = 0.6159 and ρ = -0.7916. A sUAS mounted TIR camera collected imagery four times during the growing season when SDS foliar symptoms were just starting to appear. At the start of the study period, the correlation between canopy temperature and SDS is low (ρ = -0.2907), but increases over the growing season as SDS prevalence increases ending with a strong correlation (ρ = -0.7158). Early identification of SDS leads to the implementation of mitigation practices and changes in irrigation scheduling before the disease reaches severe symptoms. Early mitigation of SDS reduces yield loses for farmers. The use of both CIR and TIR aerial imagery captured using sUAS can provide rapid spatial assessments of SDS, which is required by both producers and plant breeders. PI derived from CIR imagery showing strong correlations to SDS score reinforce the idea of replacing the time-consuming traditional ground-based systems with the more flexible, faster, sUAS methods. TIR imagery was shown to be reliable in assessing SDS in soybeans further establishing another possible aerial method for early detection of SDS.

Le médicament est un objet social qui est au coeur de diverses relations matérielles et symboliques. Pour connaitre les formes d’opinions et de savoirs qui lui sont associés au sein de la population française, nous avons mobilisé le cadre théorique des représentations sociales. En raison de la propagation massive des images dans les nouveaux médiums de communication, nous avons choisi d’aborder les différentes recherches qui constituent ce travail de thèse sous l’angle de la perspective iconographique. A ce titre, nos investigations s’articulent autour de deux axes : Le premier axe (N=946) s’intéresse à l’implication de l’imagerie mentale dans la formation de la représentation sociale du médicament. Les trois recherches réalisées en ce sens nous permettront de constater le caractère collectif de l’imagerie mentale, encourageant ainsi la recherche sur les images. Le second axe (N=615) se focalise quant à lui sur les processus mobilisés par les individus quand il s’agit de sélectionner, mémoriser et comprendre des images relatives à des associations prototypiques de la représentation sociale du médicament. Les résultats obtenus suggèrent le développement d’une méthodologie avec les images. Dans leur ensemble, les travaux invitent le lecteur d’une part, à considérer l’importance des représentations sociales dans l’exercice de décryptage des images visuelles, d’autre part, à approfondir l’iconographie dans la perspective méthodologique de la théorie des représentations sociales. / The medicine is a social object that is at the heart of many material and symbolic relationships. In order to know the opinions and knowledge associated with it within the French population, we mobilized the theoretical framework of social representations. Due to the massive spread of images in new mediums of communication, we chose to limit the research that constitutes this PhD in the iconographic perspective. As such, our investigations revolve around two axes: The first axis (N = 946) is concerned with the involvement of the mental imagery in the formation of social representation of the medicine. The three investigations carried out with this focus allowed us to observe the collective nature of mental imagery, encouraging research on the images. The second axis (N = 615) focuses in the processes mobilized by individuals when it comes to selecting, memorizing and understanding the images associated with the prototypical words of the social representation of the medicine. The results suggest the development of a methodology with the images. As a whole, the investigations invite the reader on one hand, to consider the importance of social representations in the deciphering of visual images, on the other hand to dig deeper in the iconography of the methodological perspective of the theory of social representations.

The purpose of this study was to explore the union of technical and imagery-based instruction (hereinafter, T-I instruction) in two phases. Phase one: The researcher (1) explored T-I instruction’s influences on aspiring performing artists’ acquisition of learning and performing newly composed pieces and improvisation, and; (2) observed aspiring performing artists’ feelings of learning with T-I instruction versus technical instruction. Phase two: The researcher investigated (1) listeners’ perceived expressivity of aspiring performing artists’ performances that were either influenced by T-I instruction or technical instruction; (2) listeners’ perceived expressivity of aspiring performing artists’ performances of newly composed pieces versus improvisations; (3) whether there was a statistical significant difference of T-I instructions’ influence on the progressive differences in the means of listeners’ perceived expressivity between the aspiring performing artists across the time frame of the study; (4) the explanations for their ratings, and; (5) information that helps listeners perceive music as expressive using the Perceived Expressivity Questionnaire (PEQ). Results for Phase one: 60 sub-themes and 13 themes emerged from the data relating to two meta-themes: Learning and Quality of Life. Results for Phase two: Cronbach’s alpha statistical procedure revealed an unacceptably low internal consistency for listeners’ perceived expressivity of aspiring performing artists’ performances (α = .02). Hence, no further statistical analysis was implemented to answer research questions one through three. Explanations for their ratings dealt primarily with aspiring performing artists’ use of 11 musical components. The Brief Essay Responses from the Perceived Expressivity Questionnaire (PEQ) provided possible explanations for the low internal consistency and insight on what kind of information help listeners’ perceive music as expressive. Further discussion on the finding and implications for performing artists and educators’ use of T-I instruction are offered in this document.

Despite advances in Earth observation and modeling, estimating tropical biomass remains a challenge. Recent work suggests that integrating satellite measurements of canopy height within ecosystem models is a promising approach to infer biomass. We tested the feasibility of this approach to retrieve aboveground biomass (AGB) at three tropical forest sites by assimilating remotely sensed canopy height derived from a texture analysis algorithm applied to the high-resolution Pleiades imager in the Organizing Carbon and Hydrology in Dynamic Ecosystems Canopy (ORCHIDEE-CAN) ecosystem model. While mean AGB could be estimated within 10% of AGB derived from census data in average across sites, canopy height derived from Pleiades product was spatially too smooth, thus unable to accurately resolve large height (and biomass) variations within the site considered. The error budget was evaluated in details, and systematic errors related to the ORCHIDEE-CAN structure contribute as a secondary source of error and could be overcome by using improved allometric equations.

Mental practice is a strategy that can be used to acquire the necessary skills for piano and other music performance. This type of practice strategy involves the use of imagery as opposed to the motor skills used in physical practice. In a preliminary review of piano pedagogy material and recent scientific literature, the benefits of mental practice were established. However, this review also revealed a lack of clarity in the use of terminology which sometimes interfered with readability. In order to better understand this problem of terminology, 33 current studies on mental practice in music performance were collected and examined for both the quantity and quality of term usage. Terms were identified and recorded using existing terminology and classification methods. Terminological records were created for each term appearing more than twice in the literature. In total, 83 records were created. Issues related to frequency of use (repetition), use of multiple terms (synonymy), lack of term definitions, and the need for clarity in term usage (semantic vagueness and ambiguity) were then analyzed using these records. This term analysis process resulted in the creation of a glossary and taxonomy. The glossary of 21 terms and corresponding hierarchical taxonomy (tree diagram) are proposed as an aid to help clarify the terminology of mental practice in music performance. Given the value of mental practice in learning to play music it is important to develop and maintain terminology that will facilitate both the understanding of existing literature and the design of future studies.

Measures of pain tolerance and threshold were obtained for 100 male and female subjects in a pretest treatment posttest experiment using the cold pressor test. Subjects were divided into five treatment groups with an equal representation of males and females in each group. In addition each group was divided into high and low locus of control, resulting in a 2 X 5, locus of control-by—treatment, experimental design. Treatment groups received one of the following five sets of instructions: prescribed pleasant imagery, prescribed angry imagery, self-generated pleasant imagery, self-generated angry imagery, and expectancy control. Credibility checks were obtained on all groups, and an ANOVA revealed no significant differences in credibility ratings among the groups.

After an initial four week baseline period, during which headache activity and medication consumption were monitored, 28 migraineurs were randomly assigned to one of the following groups: (a) the biofeedback temperature warming group, (b) the visual imagery group, (c) the combined treatment group, or (d) the comparison group. All four groups continued to monitor their headache activity and medication consumption during the eight week treatment period and the eight week follow-up period. A two way analysis of variance computed on groups over time indicated a significant decrease in headache activity and medication consumption. During the follow-up period (a) the combined treatment group had significantly fewer headaches than the biofeedback group or the comparison group and (b) the visual imagery group and the combined treatment group had significantly fewer headache hours than the biofeedback group or the comparison group. These results do not appear to be attributable to differences between groups on the amount of time spent in home practice or subjective ratings of relaxation. There was no consistent relationship between increases in finger temperature and headache activity improvement. Decreases in powerful other scores, as measured by the Health Attribution Test, and increases in subjective ratings of internal control were consistent with a reduction in headache activity and medication consumption.

The primary purpose of the present study is to demonstrate that acne vulgaris can be reduced by psychological treatment. A cognitive-behavioral adjunctive intervention involving biofeedback-assisted relaxation and cognitive imagery procedures for the treatment of acne vulgaris was investigated in this study with 30 patients, already receiving traditional dermatological treatment, as participants. A three-group design was used which consisted of a treatment (relaxation-imagery), a rational behavior group therapy attention-comparison, and a medical intervention control (medication and lesion extraction) group.

This study was an investigation of the effects of physiologically-oriented mental imagery on immune functioning. College students with normal medical histories were randomly selected to one of three groups. Subjects in Group 1 participated in short educational training on the production of secretory immunoglobulin A. They were then tested on salivary IgA, skin temperature and the Profile of Mood States (POMS) before and after listening to a 17-minute tape of imagery instructions with specially-composed background "entrainment" music, designed to enhance imagery. Subjects in Group 2 (placebo controls) listened to the same music but received no formal training on the immune system. Group 3 acted as a control and subjects were tested before and after 17 minutes of no activity. Treatment groups listened to their tapes at home on a bi-daily basis for six weeks. All groups were again tested at Weeks 3 and 6. Secretory IgA was analyzed using standard radial immuno-diffusion techniques. Repeated measures analyses of variance with planned orthogonal contrasts were used to evaluate the data. Significant overall increases (p < .05) were found between pre- and posttests for all three trials. Groups 1 and 2 combined (treatment groups) yielded significantly greater increases in slgA over Group 3 (control) for all three trials. Group 1 (imagery) was significantly higher than Group 2 (music) in antibody production for Trials 2 and 3. No group differences were noted in saliva volume or skin temperature, indicating that autonomic physiological mechanisms were not responsible for differences in antibody production. POMS changes more often favored Group 1. Symptomatology, recorded by subjects at weeks three and six, was significantly lower for three symptoms (rapid heartbeat, breathing difficulty, and jaw clenching), again favoring both treatment groups over the control group. Conclusions were that CNS-mediated immunoenhancement through mental imagery is possible.