Multitemporal assessment of the geomorphologic evolution of the Restinga of Marambaia, Rio de Janeiro, Brazil

The Restinga of Marambaia is an emerged sand bar located between the Sepetiba Bay and the South Atlantic Ocean, on the south-east coast of Brazil. The objective of this study was to observe the geomorphologic evolution of the coastal zone of the Restinga of Marambaia using multitemporal satellite images acquired by multisensors from 1975 to 2004. The images were digitally segmented by a region growth algorithm and submitted to an unsupervised classification procedure (ISOSEG) followed by a raster edit based on visual interpretation. The image time-series showed a general trend of decrease in the total sand bar area with values varying from 80.61km(2) in 1975 to 78.15km(2) in 2004. The total area calculation based on the 1975 and 1978 Landsat MSS data was shown to be super-estimated in relation to the Landsat TM, Landsat ETM+, and CBERS-2 CCD data. These differences can also be associated to the relatively poorer spatial resolution of the MSS data, nominally 79m, against the 20m of the CCD data and 30m of the TM and ETM+ data. For the estimates of the width in the central portion of the sand bar the variation was from 158m (1975) to 100m (2004). The formation of a spit in the northern region of the study area was visually observed. The area of the spit was estimated, with values varying from 0.82km(2) (1975) to 0.55km(2) (2004).

A comparison for a multiscale study of structural lineaments in southern Brazil: LANDSAT-7 ETM+ and shaded relief images from SRTM3-DEM

This paper presents a comparison of descriptive statistics obtained for brittle structural lineaments extracted manually from LANDSAT images and shaded relief images from SRTM 3 DEM at 1:100, 000 and 1:500, 000 scales. The selected area is located in the southern of Brazil and comprises Precambrian rocks and stratigraphic units of the Paraná Basin. The application of this methodology shows that the visual interpretation depends on the kind of remote sensing image. The resulting descriptive statistics obtained for lineaments extracted from the images do not follow the same pattern according to the scale adopted. The main direction obtained for Proterozoic rocks using both image types at a 1:500, 000 scale are close to NS±10, whereas at a 1:100, 000 scale N45E was obtained for shaded relief images from SRTM 3 DEM and N10W for LANDSAT images. The Paleozoic sediments yielded the best results for the different images and scales (N50W). On the other hand, the Mesozoic igneous rocks showed greatest differences, the shaded relief images from SRTM 3 DEM images highlighting NE structures and the LANDSAT images highlighting NW structures. The accumulated frequency demonstrated high similarity between products for each image type no matter the scale, indicating that they can be used in multiscale studies. Conversely, major differences were found when comparing data obtained using shaded relief images from SRTM 3 DEM and Landsat images at a 1:100, 000 scale.

Automated Segmentation and Non-Rigid Registration for the Quantitative Evaluation of Myocardial Perfusion from Magnetic Resonance Images

Myocardial perfusion quantification by means of Contrast-Enhanced Cardiac Magnetic Resonance images relies on time consuming frame-by-frame manual tracing of regions of interest. In this Thesis, a novel automated technique for myocardial segmentation and non-rigid registration as a basis for perfusion quantification is presented. The proposed technique is based on three steps: reference frame selection, myocardial segmentation and non-rigid registration. In the first step, the reference frame in which both endo- and epicardial segmentation will be performed is chosen. Endocardial segmentation is achieved by means of a statistical region-based level-set technique followed by a curvature-based regularization motion. Epicardial segmentation is achieved by means of an edge-based level-set technique followed again by a regularization motion. To take into account the changes in position, size and shape of myocardium throughout the sequence due to out of plane respiratory motion, a non-rigid registration algorithm is required. The proposed non-rigid registration scheme consists in a novel multiscale extension of the normalized cross-correlation algorithm in combination with level-set methods. The myocardium is then divided into standard segments. Contrast enhancement curves are computed measuring the mean pixel intensity of each segment over time, and perfusion indices are extracted from each curve. The overall approach has been tested on synthetic and real datasets. For validation purposes, the sequences have been manually traced by an experienced interpreter, and contrast enhancement curves as well as perfusion indices have been computed. Comparisons between automatically extracted and manually obtained contours and enhancement curves showed high inter-technique agreement. Comparisons of perfusion indices computed using both approaches against quantitative coronary angiography and visual interpretation demonstrated that the two technique have similar diagnostic accuracy. In conclusion, the proposed technique allows fast, automated and accurate measurement of intra-myocardial contrast dynamics, and may thus address the strong clinical need for quantitative evaluation of myocardial perfusion.

A Pseudolikelihood Approach for Simultaneous Analysis of Array Comparative Genomic Hybridizations (aCGH)

DNA sequence copy number has been shown to be associated with cancer development and progression. Array-based Comparative Genomic Hybridization (aCGH) is a recent development that seeks to identify the copy number ratio at large numbers of markers across the genome. Due to experimental and biological variations across chromosomes and across hybridizations, current methods are limited to analyses of single chromosomes. We propose a more powerful approach that borrows strength across chromosomes and across hybridizations. We assume a Gaussian mixture model, with a hidden Markov dependence structure, and with random effects to allow for intertumoral variation, as well as intratumoral clonal variation. For ease of computation, we base estimation on a pseudolikelihood function. The method produces quantitative assessments of the likelihood of genetic alterations at each clone, along with a graphical display for simple visual interpretation. We assess the characteristics of the method through simulation studies and through analysis of a brain tumor aCGH data set. We show that the pseudolikelihood approach is superior to existing methods both in detecting small regions of copy number alteration and in accurately classifying regions of change when intratumoral clonal variation is present.

Evaluation of surface defect detection in reinforced concrete bridge decks using terrestrial LiDAR

Routine bridge inspections require labor intensive and highly subjective visual interpretation to determine bridge deck surface condition. Light Detection and Ranging (LiDAR) a relatively new class of survey instrument has become a popular and increasingly used technology for providing as-built and inventory data in civil applications. While an increasing number of private and governmental agencies possess terrestrial and mobile LiDAR systems, an understanding of the technology’s capabilities and potential applications continues to evolve. LiDAR is a line-of-sight instrument and as such, care must be taken when establishing scan locations and resolution to allow the capture of data at an adequate resolution for defining features that contribute to the analysis of bridge deck surface condition. Information such as the location, area, and volume of spalling on deck surfaces, undersides, and support columns can be derived from properly collected LiDAR point clouds. The LiDAR point clouds contain information that can provide quantitative surface condition information, resulting in more accurate structural health monitoring. LiDAR scans were collected at three study bridges, each of which displayed a varying degree of degradation. A variety of commercially available analysis tools and an independently developed algorithm written in ArcGIS Python (ArcPy) were used to locate and quantify surface defects such as location, volume, and area of spalls. The results were visual and numerically displayed in a user-friendly web-based decision support tool integrating prior bridge condition metrics for comparison. LiDAR data processing procedures along with strengths and limitations of point clouds for defining features useful for assessing bridge deck condition are discussed. Point cloud density and incidence angle are two attributes that must be managed carefully to ensure data collected are of high quality and useful for bridge condition evaluation. When collected properly to ensure effective evaluation of bridge surface condition, LiDAR data can be analyzed to provide a useful data set from which to derive bridge deck condition information.

A comparison of pixel and object-based land cover classification. A case study of the Asmara region, Eritrea

In this paper we compare the performance of two image classification paradigms (object- and pixel-based) for creating a land cover map of Asmara, the capital of Eritrea and its surrounding areas using a Landsat ETM+ imagery acquired in January 2000. The image classification methods used were maximum likelihood for the pixel-based approach and Bhattacharyya distance for the object-oriented approach available in, respectively, ArcGIS and SPRING software packages. Advantages and limitations of both approaches are presented and discussed. Classifications outputs were assessed using overall accuracy and Kappa indices. Pixel- and object-based classification methods result in an overall accuracy of 78% and 85%, respectively. The Kappa coefficient for pixel- and object-based approaches was 0.74 and 0.82, respectively. Although pixel-based approach is the most commonly used method, assessment and visual interpretation of the results clearly reveal that the object-oriented approach has advantages for this specific case-study.

Ventilation/perfusion SPECT/CT in patients with pulmonary emphysema. Evaluation of software-based analysing

UNLABELLED The purpose of this study was to evaluate the reproducibility of a new software based analysing system for ventilation/perfusion single-photon emission computed tomography/computed tomography (V/P SPECT/CT) in patients with pulmonary emphysema and to compare it to the visual interpretation. PATIENTS, MATERIAL AND METHODS 19 patients (mean age: 68.1 years) with pulmonary emphysema who underwent V/P SPECT/CT were included. Data were analysed by two independent observers in visual interpretation (VI) and by software based analysis system (SBAS). SBAS PMOD version 3.4 (Technologies Ltd, Zurich, Switzerland) was used to assess counts and volume per lung lobe/per lung and to calculate the count density per lung, lobe ratio of counts and ratio of count density. VI was performed using a visual scale to assess the mean counts per lung lobe. Interobserver variability and association for SBAS and VI were analysed using Spearman's rho correlation coefficient. RESULTS Interobserver agreement correlated highly in perfusion (rho: 0.982, 0.957, 0.90, 0.979) and ventilation (rho: 0.972, 0.924, 0.941, 0.936) for count/count density per lobe and ratio of counts/count density in SBAS. Interobserver agreement correlated clearly for perfusion (rho: 0.655) and weakly for ventilation (rho: 0.458) in VI. CONCLUSIONS SBAS provides more reproducible measures than VI for the relative tracer uptake in V/P SPECT/CTs in patients with pulmonary emphysema. However, SBAS has to be improved for routine clinical use.

Elementos visuales determinantes del Paisaje Litoral. El potencial presente y endógeno en la Confluencia del Tajo con el Atlántico

El objeto de esta tesis es analizar la calidad del paisaje litoral como realidad espacial captada e interpretada por el hombre, a partir de la elección de elementos descriptibles y valorables, que ayudan a encuadrar y relacionar los principales aspectos, componentes, variables y parámetros asociados a la apreciación visual del territorio costero. Resumo Este trabalho tem como objecto de estudo a análise da qualidade da paisagem litoral, enquanto realidade espacial percepcionada e interpretada pelo homem a partir de elementos descritíveis e valoráveis, enquadrando, relacionando e caracterizando os principais aspectos, componentes, variáveis e parâmetros relacionados com a apreciação visual do território costeiro. Résumé Cette thèse a pour objet l'analyse du paysage littoral en tant que réalité spatiale perçue et traduite à partir d'éléments qui peuvent être décrits et mesurés pour servir ensuite à interpréter, caractériser et mettre en relation les principaux aspects, composants, variables et paramètres liés à l'interprétation visuelle du territoire côtier. Abstract The object of this project is to analyse the littoral landscape as a spatial reality perceived and interpreted by mankind, with reference to those elements that can be described and measured, thereby categorizing, connecting and characterizing the principal aspects, components, variables and parameters which relate to the visual interpretation of the coastal territory. Riassunto Questo lavoro ha come obbiettivo di studio l'analisi della qualità del paesaggio litoraneo, inteso come realtà particolare percepita ed interpretata dall'uomo a partire da elementi descrittivi e di valutazione, inquadrando, mettendo in relazione e distinguendo i principali aspetti, componenti, variabili e parametri relativi all'interpretazione visiva del territorio costiero. Zusammenfassung Ziel dieses Projekts ist es, die Eigenschaften der Küstenlandschaft, wie sie vom Menschen als räumliche Wirklichkeit wahrgenommen und gedeutet wird, unter Verwendung der beschreibbaren und messbaren Elemente zu analysieren, und die Hauptaspekte, Bestandteile, Variablen und Parameter der visuellen Interpretation des Küstengebiets einzubeziehen und zu charakterisieren. Samenvatting Het doel van dit project is het analyseren van de kwaliteit van het kustlandschap, zoals dit landschap door mensen als realiteit waargenomen en geïnterpreteerd, geinterpreteerd wordt, daarbij gebruik makende van beschrijfbare en meetbare elementen en tegelijkertijd daarbij in te passen, te verbinden en te karakteriseren de hoofdaspecten, componenten, variabelen en parameters die betrekking hebben op op visuele interpretatie van het kustlandschap.

Improving parameters selection of a seeded region growing method for multiband image segmentation

In the last decade, Object Based Image Analysis (OBIA) has been accepted as an effective method for processing high spatial resolution multiband images. This image analysis method is an approach that starts with the segmentation of the image. Image segmentation in general is a procedure to partition an image into homogenous groups (segments). In practice, visual interpretation is often used to assess the quality of segmentation and the analysis relies on the experience of an analyst. In an effort to address the issue, in this study, we evaluate several seed selection strategies for an automatic image segmentation methodology based on a seeded region growing-merging approach. In order to evaluate the segmentation quality, segments were subjected to spatial autocorrelation analysis using Moran's I index and intra-segment variance analysis. We apply the algorithm to image segmentation using an aerial multiband image.

The application of remote sensing to water resources

Techniques are developed for the visual interpretation of drainage features from satellite imagery. The process of interpretation is formalised by the introduction of objective criteria. Problems of assessing the accuracy of maps are recognized, and a method is developed for quantifying the correctness of an interpretation, in which the more important features are given an appropriate weight. A study was made of imagery from a variety of landscapes in Britain and overseas, from which maps of drainage networks were drawn. The accuracy of the mapping was assessed in absolute terms, and also in relation to the geomorphic parameters used in hydrologic models. Results are presented relating the accuracy of interpretation to image quality, subjectivity and the effects of topography. It is concluded that the visual interpretation of satellite imagery gives maps of sufficient accuracy for the preliminary assessment of water resources, and for the estimation of geomorphic parameters. An examination is made of the use of remotely sensed data in hydrologic models. It is proposed that the spectral properties of a scene are holistic, and are therefore more efficient than conventional catchment characteristics. Key hydrologic parameters were identified, and were estimated from streamflow records. The correlation between hydrologic variables and spectral characteristics was examined, and regression models for streamflow were developed, based solely on spectral data. Regression models were also developed using conventional catchment characteristics, whose values were estimated using satellite imagery. It was concluded that models based primarily on variables derived from remotely sensed data give results which are as good as, or better than, models using conventional map data. The holistic properties of remotely sensed data are realised only in undeveloped areas. In developed areas an assessment of current land-use is a more useful indication of hydrologic response.

The use of spot simulation imagery for forestry mapping and management

SPOT simulation imagery was acquired for a test site in the Forest of Dean in Gloucestershire, U.K. This data was qualitatively and quantitatively evaluated for its potential application in forest resource mapping and management. A variety of techniques are described for enhancing the image with the aim of providing species level discrimination within the forest. Visual interpretation of the imagery was more successful than automated classification. The heterogeneity within the forest classes, and in particular between the forest and urban class, resulted in poor discrimination using traditional `per-pixel' automated methods of classification. Different means of assessing classification accuracy are proposed. Two techniques for measuring textural variation were investigated in an attempt to improve classification accuracy. The first of these, a sequential segmentation method, was found to be beneficial. The second, a parallel segmentation method, resulted in little improvement though this may be related to a combination of resolution in size of the texture extraction area. The effect on classification accuracy of combining the SPOT simulation imagery with other data types is investigated. A grid cell encoding technique was selected as most appropriate for storing digitised topographic (elevation, slope) and ground truth data. Topographic data were shown to improve species-level classification, though with sixteen classes overall accuracies were consistently below 50%. Neither sub-division into age groups or the incorporation of principal components and a band ratio significantly improved classification accuracy. It is concluded that SPOT imagery will not permit species level classification within forested areas as diverse as the Forest of Dean. The imagery will be most useful as part of a multi-stage sampling scheme. The use of texture analysis is highly recommended for extracting maximum information content from the data. Incorporation of the imagery into a GIS will both aid discrimination and provide a useful management tool.

Une étude générique du metteur en scène au théâtre:son émergence et son rôle moderne et contemporain

The theatre director (metteur en scene in French) is a relatively new figure in theatre practice. It was not until the I820s that the term 'mise en scene' gained currency. The term 'director' was not in general use until the I880s. The emergence and the role of the director has been considered from a variety of perspectives, either through the history of theatre (Allevy, Jomaron, Sarrazac, Viala, Biet and Triau); the history of directing (Chinoy and Cole, Boll, Veinstein, Roubine); semiotic approaches to directing (Whitmore, Miller, Pavis); the semiotics of performance (De Marinis); generic approaches to the mise en scene (Thomasseau, Banu); post-dramatic approaches to theatre (Lehmann); approaches to performance process and the specifics of rehearsal methodology (Bradby and Williams, Giannachi and Luckhurst, Picon-Vallin, Styan). What the scholarly literature has not done so far is to map the parameters necessarily involved in the directing process, and to incorporate an analysis of the emergence of the theatre director during the modem period and consider its impact on contemporary performance practice. Directing relates primarily to the making of the performance guided by a director, a single figure charged with the authority to make binding artistic decisions. Each director may have her/his own personal approaches to the process of preparation prior to a show. This is exemplified, for example, by the variety of terms now used to describe the role and function of directing, from producer, to facilitator or outside eye. However, it is essential at the outset to make two observations, each of which contributes to a justification for a generic analysis (as opposed to a genetic approach). Firstly, a director does not work alone, and cooperation with others is involved at all stages of the process. Secondly, beyond individual variation, the role of the director remains twofold. The first is to guide the actors (meneur de jeu, directeur d'acteurs, coach); the second is to make a visual representation in the performance space (set designer, stage designer, costume designer, lighting designer, scenographe). The increasing place of scenography has brought contemporary theatre directors such as Wilson, Castellucci, Fabre to produce performances where the performance space becomes a semiotic dimension that displaces the primacy of the text. The play is not, therefore, the sole artistic vehicle for directing. This definition of directing obviously calls for a definition of what the making of the performance might be. The thesis defines the making of the performance as the activity of bringing a social event, by at least one performer, providing visual and/or textual meaning in a performance space. This definition enables us to evaluate four consistent parameters throughout theatre history: first, the social aspect associated to the performance event; second, the devising process which may be based on visual and/or textual elements; third, the presence of at least one performer in the show; fourth, the performance space (which is not simply related to the theatre stage). Although the thesis focuses primarily on theatre practice, such definition blurs the boundaries between theatre and other collaborative artistic disciplines (cinema, opera, music and dance). These parameters illustrate the possibility to undertake a generic analysis of directing, and resonate with the historical, political and artistic dimensions considered. Such a generic perspective on the role of the director addresses three significant questions: an historical question: how/why has the director emerged?; a sociopolitical question: how/why was the director a catalyst for the politicisation of theatre, and subsequently contributed to the rise of State-funded theatre policy?; and an artistic one: how/why the director has changed theatre practice and theory in the twentieth-century? Directing for the theatre as an artistic activity is a historically situated phenomenon. It would seem only natural from a contemporary perspective to associate the activity of directing to the function of the director. This is relativised, however, by the question of how the performance was produced before the modern period. The thesis demonstrates that the rise of the director is a progressive and historical phenomenon (Dort) rather than a mere invention (Viala, Sarrazac). A chronological analysis of the making of the performance throughout theatre history is the most useful way to open the study. In order to understand the emergence of the director, the research methodology assesses the interconnection of the four parameters above throughout four main periods of theatre history: the beginning of the Renaissance (meneur de jeu), the classical age (actor-manager and stage designer-manager), the modern period (director) and the contemporary period (director-facilitator, performer). This allows us properly to appraise the progressive emergence of the director, as well as to make an analysis of her/his modern and contemporary role. The first chapter argues that the physical separation between the performance space and its audience, which appeared in the early fifteenth-century, has been a crucial feature in the scenographic, aesthetic, political and social organisation of the performance. At the end of the Middle Ages, French farces which raised socio-political issues (see Bakhtin) made a clear division on a single outdoor stage (treteau) between the actors and the spectators, while religious plays (drame fiturgique, mystere) were mostly performed on various outdoor and opened multispaces. As long as the performance was liturgical or religious, and therefore confined within an acceptable framework, it was allowed. At the time, the French ecclesiastical and civil authorities tried, on several occasions, to prohibit staged performances. As a result, practitioners developed non-official indoor spaces, the Theatre de fa Trinite (1398) being the first French indoor theatre recognized by scholars. This self-exclusion from the open public space involved breaking the accepted rules by practitioners (e.g. Les Confreres de fa Passion), in terms of themes but also through individual input into a secular performance rather than the repetition of commonly known religious canvases. These developments heralded the authorised theatres that began to emerge from the mid-sixteenth century, which in some cases were subsidised in their construction. The construction of authorised indoor theatres associated with the development of printing led to a considerable increase in the production of dramatic texts for the stage. Profoundly affecting the reception of the dramatic text by the audience, the distance between the stage and the auditorium accompanied the changing relationship between practitioners and spectators. This distance gave rise to a major development of the role of the actor and of the stage designer. The second chapter looks at the significance of both the actor and set designer in the devising process of the performance from the sixteenth-century to the end of the nineteenth-century. The actor underwent an important shift in function in this period from the delivery of an unwritten text that is learned in the medieval oral tradition to a structured improvisation produced by the commedia dell 'arte. In this new form of theatre, a chef de troupe or an experienced actor shaped the story, but the text existed only through the improvisation of the actors. The preparation of those performances was, moreover, centred on acting technique and the individual skills of the actor. From this point, there is clear evidence that acting began to be the subject of a number of studies in the mid-sixteenth-century, and more significantly in the seventeenth-century, in Italy and France. This is revealed through the implementation of a system of notes written by the playwright to the actors (stage directions) in a range of plays (Gerard de Vivier, Comedie de la Fidelite Nuptiale, 1577). The thesis also focuses on Leoni de' Sommi (Quatro dialoghi, 1556 or 1565) who wrote about actors' techniques and introduced the meneur de jeu in Italy. The actor-manager (meneur de jeu), a professional actor, who scholars have compared to the director (see Strihan), trained the actors. Nothing, however, indicates that the actor-manager was directing the visual representation of the text in the performance space. From the end of the sixteenth-century, the dramatic text began to dominate the process of the performance and led to an expansion of acting techniques, such as the declamation. Stage designers carne from outside the theatre tradition and played a decisive role in the staging of religious celebrations (e.g. Actes des Apotres, 1536). In the sixteenth-century, both the proscenium arch and the borders, incorporated in the architecture of the new indoor theatres (theatre a l'italienne), contributed to create all kinds of illusions on the stage, principally the revival of perspective. This chapter shows ongoing audience demands for more elaborate visual effects on the stage. This led, throughout the classical age, and even more so during the eighteenth-century, to grant the stage design practitioner a major role in the making of the performance (see Ciceri). The second chapter demonstrates that the guidance of the actors and the scenographic conception, which are the artistic components of the role of the director, appear to have developed independently from one another until the nineteenth-century. The third chapter investigates the emergence of the director per se. The causes for this have been considered by a number of scholars, who have mainly identified two: the influence of Naturalism (illustrated by the Meiningen Company, Antoine, and Stanislavski) and the invention of electric lighting. The influence of the Naturalist movement on the emergence of the modem director in the late nineteenth-century is often considered as a radical factor in the history of theatre practice. Naturalism undoubtedly contributed to changes in staging, costume and lighting design, and to a more rigorous commitment to the harmonisation and visualisation of the overall production of the play. Although the art of theatre was dependent on the dramatic text, scholars (Osborne) demonstrate that the Naturalist directors did not strictly follow the playwright's indications written in the play in the late nineteenth-century. On the other hand, the main characteristic of directing in Naturalism at that time depended on a comprehensive understanding of the scenography, which had to respond to the requirements of verisimilitude. Electric lighting contributed to this by allowing for the construction of a visual narrative on stage. However, it was a master technician, rather than an emergent director, who was responsible for key operational decisions over how to use this emerging technology in venues such as the new Bayreuth theatre in 1876. Electric lighting reflects a normal technological evolution and cannot be considered as one of the main causes of the emergence of the director. Two further causes of the emergence of the director, not considered in previous studies, are the invention of cinema and the Symbolist movement (Lugne-Poe, Meyerhold). Cinema had an important technological influence on the practitioners of the Naturalist movement. In order to achieve a photographic truth on the stage (tableau, image), Naturalist directors strove to decorate the stage with the detailed elements that would be expected to be found if the situation were happening in reality. Film production had an influence on the work of actors (Walter). The filmmaker took over a primary role in the making of the film, as the source of the script, the filming process and the editing of the film. This role influenced the conception that theatre directors had of their own work. It is this concept of the director which influenced the development of the theatre director. As for the Symbolist movement, the director's approach was to dematerialise the text of the playwright, trying to expose the spirit, movement, colour and rhythm of the text. Therefore, the Symbolists disengaged themselves from the material aspect of the production, and contributed to give greater artistic autonomy to the role of the director. Although the emergence of the director finds its roots amongst the Naturalist practitioners (through a rigorous attempt to provide a strict visual interpretation of the text on stage), the Symbolist director heralded the modem perspective of the making of performance. The emergence of the director significantly changed theatre practice and theory. For instance, the rehearsal period became a clear work in progress, a platform for both developing practitioners' techniques and staging the show. This chapter explores and contrasts several practitioners' methods based on the two aspects proposed for the definition of the director (guidance of the actors and materialisation of a visual space). The fourth chapter argues that the role of the director became stronger, more prominent, and more hierarchical, through a more political and didactic approach to theatre as exemplified by the cases of France and Germany at the end of the nineteenth-century and through the First World War. This didactic perspective to theatre defines the notion of political theatre. Political theatre is often approached by the literature (Esslin, Willett) through a Marxist interpretation of the great German directors' productions (Reinhardt, Piscator, Brecht). These directors certainly had a great influence on many directors after the Second World War, such as Jean Vilar, Judith Molina, Jean-Louis Barrault, Roger Planchon, Augusto Boal, and others. This chapter demonstrates, moreover, that the director was confirmed through both ontological and educational approaches to the process of making the performance, and consequently became a central and paternal figure in the organisational and structural processes practiced within her/his theatre company. In this way, the stance taken by the director influenced the State authorities in establishing theatrical policy. This is an entirely novel scholarly contribution to the study of the director. The German and French States were not indifferent to the development of political theatre. A network of public theatres was thus developed in the inter-war period, and more significantly after the Second World War. The fifth chapter shows how State theatre policies establish its sources in the development of political theatre, and more specifically in the German theatre trade union movement (Volksbiihne) and the great directors at the end of the nineteenth-century. French political theatre was more influenced by playwrights and actors (Romain Rolland, Louise Michel, Louis Lumet, Emile Berny). French theatre policy was based primarily on theatre directors who decentralised their activities in France during both the inter-war period and the German occupation. After the Second World War, the government established, through directors, a strong network of public theatres. Directors became both the artistic director and the executive director of those institutionalised theatres. The institution was, however, seriously shaken by the social and political upheaval of 1968. It is the link between the State and the institution in which established directors were entangled that was challenged by the young emerging directors who rejected institutionalised responsibility in favour of the autonomy of the artist in the 1960s. This process is elucidated in chapter five. The final chapter defines the contemporary role of the director in contrasting thework of a number of significant young theatre practitioners in the 1960s such as Peter Brook, Ariane Mnouchkine, The Living Theater, Jerzy Grotowski, Augusto Boal, Eugenio Barba, all of whom decided early on to detach their companies from any form of public funding. This chapter also demonstrates how they promoted new forms of performance such as the performance of the self. First, these practitioners explored new performance spaces outside the traditional theatre building. Producing performances in a non-dedicated theatre place (warehouse, street, etc.) was a more frequent practice in the 1960s than before. However, the recent development of cybertheatre questions both the separation of the audience and the practitioners and the place of the director's role since the 1990s. Secondly, the role of the director has been multifaceted since the 1960s. On the one hand, those directors, despite all their different working methods, explored western and non-western acting techniques based on both personal input and collective creation. They challenged theatrical conventions of both the character and the process of making the performance. On the other hand, recent observations and studies distinguish the two main functions of the director, the acting coach and the scenographe, both having found new developments in cinema, television, and in various others events. Thirdly, the contemporary director challenges the performance of the text. In this sense, Antonin Artaud was a visionary. His theatre illustrates the need for the consideration of the totality of the text, as well as that of theatrical production. By contrasting the theories of Artaud, based on a non-dramatic form of theatre, with one of his plays (Le Jet de Sang), this chapter demonstrates how Artaud examined the process of making the performance as a performance. Live art and autobiographical performance, both taken as directing the se(f, reinforce this suggestion. Finally, since the 1990s, autobiographical performance or the performance of the self is a growing practical and theoretical perspective in both performance studies and psychology-related studies. This relates to the premise that each individual is making a representation (through memory, interpretation, etc.) of her/his own life (performativity). This last section explores the links between the place of the director in contemporary theatre and performers in autobiographical practices. The role of the traditional actor is challenged through non-identification of the character in the play, while performers (such as Chris Burden, Ron Athey, Orlan, Franko B, Sterlac) have, likewise, explored their own story/life as a performance. The thesis demonstrates the validity of the four parameters (performer, performance space, devising process, social event) defining a generic approach to the director. A generic perspective on the role of the director would encompass: a historical dimension relative to the reasons for and stages of the 'emergence' of the director; a socio-political analysis concerning the relationship between the director, her/his institutionalisation, and the political realm; and the relationship between performance theory, practice and the contemporary role of the director. Such a generic approach is a new departure in theatre research and might resonate in the study of other collaborative artistic practices.

Influência da escala de cores na avaliação qualitativa das imagens de cintigrafia de perfusão do miocárdio

Introdução – A cintigrafia de perfusão do miocárdio (CPM) é utilizada no diagnóstico e seguimento de pacientes com doença arterial coronária, sendo a sua avaliação frequentemente realizada através da análise visual dos cortes tomográficos. A escala de cores selecionada é essencial na interpretação clínica das imagens de perfusão do miocárdio. Objetivo – Avaliar a influência de diferentes escalas de cores na avaliação qualitativa das imagens de CPM e estudar quais as mais adequadas para análise visual. Métodos – Trinta e cinco estudos de CPM foram avaliados visualmente por 16 estudantes da licenciatura em medicina nuclear nas escalas de cores Cool, Gray, Gray Invert, Thermal e Warm. Para a escala de cores Cool, a análise das imagens de CPM foi realizada através de um sistema de classificação semiquantitativo por scores. As restantes escalas de cores foram avaliadas por comparação com a análise das imagens efetuada com escala de cores Cool. Resultados/Discussão – Para a escala de cores Cool, a variabilidade interoperador revelou a existência de diferenças estatisticamente significativas entre todos os participantes (p<0,05), o que se pode atribuir à subjetividade da avaliação visual. Os resultados relativos às escalas de cores Gray e Gray Invert foram os mais próximos da perfusão do miocárdio observada com a escala Cool, considerando-se escalas de cores alternativas na análise visual dos estudos de CPM. Para as escalas de cores Thermal e Warm os resultados foram mais divergentes, não se considerando adequadas para a avaliação visual dos estudos de CPM. Conclusão – A escala de cores influencia a avaliação qualitativa da perfusão na CPM.

Aplicação para pesquisa de clip arts em dispositivos móveis baseada em esboços

Trabalho Final de Mestrado para obtenção do Grau de Mestre em Engenharia de Redes de Comunicação e Multimédia

A contribution to semantic description of images and videos: an application of soft biometrics

Humans have a high ability to extract visual data information acquired by sight. Trought a learning process, which starts at birth and continues throughout life, image interpretation becomes almost instinctively. At a glance, one can easily describe a scene with reasonable precision, naming its main components. Usually, this is done by extracting low-level features such as edges, shapes and textures, and associanting them to high level meanings. In this way, a semantic description of the scene is done. An example of this, is the human capacity to recognize and describe other people physical and behavioral characteristics, or biometrics. Soft-biometrics also represents inherent characteristics of human body and behaviour, but do not allow unique person identification. Computer vision area aims to develop methods capable of performing visual interpretation with performance similar to humans. This thesis aims to propose computer vison methods which allows high level information extraction from images in the form of soft biometrics. This problem is approached in two ways, unsupervised and supervised learning methods. The first seeks to group images via an automatic feature extraction learning , using both convolution techniques, evolutionary computing and clustering. In this approach employed images contains faces and people. Second approach employs convolutional neural networks, which have the ability to operate on raw images, learning both feature extraction and classification processes. Here, images are classified according to gender and clothes, divided into upper and lower parts of human body. First approach, when tested with different image datasets obtained an accuracy of approximately 80% for faces and non-faces and 70% for people and non-person. The second tested using images and videos, obtained an accuracy of about 70% for gender, 80% to the upper clothes and 90% to lower clothes. The results of these case studies, show that proposed methods are promising, allowing the realization of automatic high level information image annotation. This opens possibilities for development of applications in diverse areas such as content-based image and video search and automatica video survaillance, reducing human effort in the task of manual annotation and monitoring.