Academic literature on the topic 'Graphical technique'

Includes bibliographical references.<br>This dissertation concerns the specification and description of complex communicating systems using Formal Description Techniques. Specifically, we propose a standard graphical representation for the Formal Description Technique Estelle and present a prototype editor based on this representation. Together they integrate the new graphical representation with existing Estelle textual tools to create a powerful graphical design technique for Estelle. The perennial popularity of graphical techniques, combined with recent advances in computer graphics hardware and software which enable their effective application in a computing environment, provide a double impetus for the development of a graphical representation for Estelle. Most importantly, a graphical technique is more easily read and understood by humans, and can better describe the complex structure and inter-relationships of components of concurrent communicating systems. Modern graphical technology also presents a number of opportunities, separate from the specification method, such as hyperlinking, multiple windows and hiding of detail, which enrich the graphical technique. The prototype editor makes use of these opportunities to provide the protocol engineer with an advanced interface which actively supports the protocol design process to improve the quality of design. The editor also implements translations between the graphical representation and the standard Estelle textual representation, on the one hand allowing the graphical interpretation to be applied to existing textual specifications, and on the other, the application of existing text-based processing tools to a graphical specification description.

The process of visualizing n-D data presents the user with four problems: finding a hyperdimensional graphics package capable of rendering n-D data, finding a suitable presentation technique supported by the package that allows insight to be gained, using the provided user interface to interact with the presentation technique to explore the information in the data, and finding a way to share the information gained with others. Many graphics packages have been written to solve the first problem. However, existing packages do not sufficiently solve the other three problems. A hyperdimensional graphics package that sufficiently solves all these problems simplifies the user experience and allows the user to explore, interact with, and share the data. I have implemented a package that solves all four problems. The package is able to render n-D data through appropriate encapsulation of presentation techniques and their associated visual cues. Through the use of an extensible plugin system, presentation techniques can be easily added and accommodated. Desirable features are supported by the user interface to allow the user to interact easily with the data. Sharing of visualizations and annotations are included to allow users to share information with one another. By providing a hyperdimensional graphics package that easily accommodates presentation techniques and includes desirable features, including those that are rarely or never supported, the user benefits from tools that allow improved interaction with multivariate data to extract information and share it with others.

Les graphiques ont pris de plus en plus d'importance dans le matériel pédagogique, les manuels scolaires ou encore les programmes informatiques. Malgré la coexistence de différents types de graphiques ou de genres graphiques, jusqu'à maintenant, les recherches sur l'apprentissage ont seulement pris en compte la distinction entre le texte et l'image. Cette thèse vise à éclaircir ce qui, dans la recherche sur l'apprentissage, semble être une catégorie globale et indivisible : les représentations visuelles. Nous nous sommes concentrées sur ce que pensent des enseignants et des étudiants de Master concernant différents types de représentations visuelles et leurs fonctions présumées dans l'enseignement et l'apprentissage. A l'heure actuelle, la recherche sur les graphiques est principalement axée sur la compréhension des élèves. Il existe très peu de recherches sur la compréhension des graphiques par les enseignants. En outre, la dimension de la formation des enseignants aux graphiques est, elle aussi, relativement ignorée. La thèse se présente en deux parties : une recherche théorique suivie d'une recherche empirique. La première partie du travail examine la littérature relative aux représentations graphiques dans l'histoire, dans les programmes scolaires à travers le monde ainsi que leur utilisation dans l'enseignement et l'apprentissage. Elle expose également les classifications des différents types de graphiques. La seconde partie de la thèse prend appui sur trois enquêtes menées auprès d'enseignants en activité et d'étudiants de Master en formation. La première investigue la compréhension des graphiques d'enseignants en activité en France et au Pakistan. Les deux autres ont été conduites auprès de futurs enseignants, en utilisant la méthode du tri de carte, afin d'identifier leurs compétences relatives à la catégorisation des différents types de graphiques.En conclusion, il semble que les programmes de formation des enseignants manquent d'un enseignement à la compréhension graphique. Même en géographie, pourtant considérée comme la discipline des graphiques et de leur enseignement, nous constatons que les enseignants sont peu familiers avec de nombreux genres graphiques. Dans l'ensemble, les graphiques génériques (camemberts, histogrammes, cartes et tableaux, etc.) ont été facilement identifiés par les enseignants alors que la classification des graphiques hybrides s'est révélée plus difficile pour la plupart d'entre eux<br>Visualizations have gained more importance in pedagogical material, in text books and in computer programs. Despite the co-existence of many different types of visualizations or graphical genres, learning research only has taken into account the distinction between text and pictures. This thesis aims at unpacking what, at least in learning research, seems to be one single holistic indivisible category of visualizations. We focused on teachers' and Masters students' thoughts on the existence of different types of visualizations and their presumed function in teaching and learning. Research on graphical representations is mainly focused on students' comprehension of graphical representations. However, there is very little research in extend of teachers' comprehension of graphical representations. In addition, the aspect of teacher training of graphical representations is also relatively ignored. There are two main parts in this thesis: theoretical and empirical. In theoretical part, we presented the literature on the existence of graphical representations in worldwide curricula. Remarkable works of cartographers who played important rule for the advancement of graphic representations in context of teaching and learning. And finally, classification of different genres of graphical representations was also exhibited. Empirical part on the other hand, based on three studies conducted with in-service teachers and Masters students' about their comprehension of graphical genres. First study was conducted with in-service teachers from France and Pakistan to investigate their basic understanding of graphical representations. Second and third study explores the Masters' students' categorization of graphical representations. In conclusion, it seems that the teacher training programs lack the training of graphic comprehension. Even in the domain of geography which is considered the major domain about graphics and graphic education, teachers were observed unfamiliar with many graphic genres. Overall, Generic graphical representations (i.e. line graph, pie charts, bar charts, maps and tables etc.) were identified more comfortably. However, classification of hybrid graphical representations (i.e. combination of map and bar graph or other hybrid graphics) was slightly difficult for the participants

With the abundance of written information available online, it is useful to be able to automatically synthesize and extract meaningful information from text corpora. We present a unique method for visualizing relationships between documents in a text corpus. By using Latent Dirichlet Allocation to extract topics from the corpus, we create a graph whose nodes represent individual documents and whose edge weights indicate the distance between topic distributions in documents. These edge lengths are then scaled using multidimensional scaling techniques, such that more similar documents are clustered together. Applying this method to several datasets, we demonstrate that these graphs are useful in visually representing high-dimensional document clustering in topic-space.

Thesis (MScEng)-- Stellenbosch University, 2013.<br>ENGLISH ABSTRACT: Organizations formally define and document their business processes in order to properly understand them and to subsequently enable their continuous development, improvement and management. In order to formally define and document their business processes, organizations can use Business Process Modelling, which represents the design of graphical models that portray the business processes of organizations. It is however noted that it is difficult to select a suitable Business Process Modelling Technique in support of a specific application of Business Process Modelling. This is due to the considerable amount of existing Business Process Modelling Techniques, the inherent impact of their varying capabilities and the lack of formal measures that are available to support evaluations regarding their suitability for specific modelling applications. It is therefore considered appropriate to execute a research study that is aimed at the development and validation of a measurement framework that can be used to evaluate the suitability of Business Process Modelling Techniques for specific modelling applications.<br>AFRIKAANSE OPSOMMING: Organisasies definieer en dokumenteer hulle besigheidsprosesse op ʼn formele wyse om hulle ordentlik te verstaan en gevolglik hulle deurlopende ontwikkeling, verbetering en bestuur te bemagtig. Ten einde die uitvoering van hierdie aktiwiteit aan te spreek, kan organisasies Besigheidsproses Modellering gebruik om grafiese modelle van hulle besigheidsprosesse te ontwerp. Daar word egter kennis geneem dat dit moeilik is om ʼn geskikte Besigheidsproses Modellering Tegniek te kies tes ondersteuning van ʼn spesifieke toepassing van Besigheidsproses Modellering. Dit is weens die groot hoeveelheid bestaande Besigheidsproses Modellering Tegnieke, die impak van hulle variërende vermoëns asook die gebrek aan formele maatstawwe wat gebruik kan word om hulle geskiktheid vir spesifieke modellering toepassings te evalueer. Dit lei tot die besluit om ‘n studie te voltooi wat gefokus is op die ontwikkeling en validasie van ʼn metings raamwerk wat gebruik kan word om die geskiktheid van Besigheidsproses Modellering Tegnieke vir spesifieke toepassings van Besigheidproses Modellering te evalueer.

Includes bibliography.<br>The thesis deals with graphical display techniques based on the singular value decomposition. These techniques, known as biplots, are used to find low dimensional representations of multidimensional data matrices. The aim of the thesis is to provide a review of biplots for a practical statistician who is not familiar with the area. It therefore focuses on the underlying theory, assuming a standard statisticians' knowledge of matrix algebra, and on the interpretation of the various plots. The topic falls in the realm of descriptive statistics. As such, the methods are chiefly exploratory. They are a means of summarising the data. The data matrix is represented in a reduced number of dimensions, usually two, for simplicity of display. The aim is to summarise the information in the matrix and to present a visual representation of this information. The aim in using graphical display techniques is that the "gain in interpretability far exceeds the loss in information" (Greenacre, 1984). A graphical description is often more easy to understand than a numerical one. Histograms and pie charts are familiar forms of data representation to many people with no other, or very rudimentary, statistical understanding. These are applicable to univariate data. For multivariate data sets, univariate methods do not reveal interesting relationships in the data set as a whole. In addition, a biplot can be presented in a manner which can be readily understood by non-statistically minded individuals. Greenacre (1984) comments that only in recent years has the value of statistical graphics been recognised. Young (1989) notes that recently there has been a shift in emphasis, among statisticians towards exploratory data analysis methods. This school of thought was given momentum by the publication of the book "Exploratory Data Analysis" (Tukey, 1977). The trend has been facilitated by advances in computer technology which have increased both the power and the accessibility of computers. Biplot techniques include the popular correspondence analysis. The original proponents of correspondence analysis (among them Benzecri) reject probabilistic modelling. At the other extreme, some view graphical display techniques as a mere preliminary to the more traditional statistical approaches. Under the latter view, graphical display techniques are used to suggest models and hypotheses. The emphasis in exploratory data techniques such as graphical displays is on 'getting a feel' for the data rather than on building models and testing hypotheses. These methods do not replace model building and hypothesis testing, but supplement them. The essence of the philosophy is that models are suggested by the data, rather than the frequently followed route of first fitting a model. Some work has gone into developing inferential methods, with hypothesis tests and associated p-values for biplot-type techniques (Lebart et al, 1984, Greenacre, 1984). However, this aspect is not important if the techniques are viewed merely as exploratory. Chapter Two provides the mathematical concepts necessary for understanding biplots. Chapter Three explains exactly what a biplot is, and lays the theoretical framework for the biplot techniques that follow. The goal of this chapter is to provide a framework in which biplot techniques can be classified and described. Correlation biplots are described in Chapter Four. Chapter Five discusses the principal component biplot, and the link between these and principal component analysis is drawn. In Chapter Six, correspondence analysis is presented. In Chapter Seven practical issues such as choice of centre are discussed. Practical examples are presented in Chapter Eight. The aim is that these examples illustrate techniques commonly applicable in practice. Evaluation and choice of biplot is discussed in Chapter Nine.

Dissertation submitted in partial fulfilment of the requirements for the degree Master of Technology: Graphic Design in the Faculty of Informatics and Design at the Cape Peninsula University of Technology<br>This study investigates the application and use of the latest graphic design software technologies to help plan and ideate the intaglio printmaking process. This is significant as intaglio is a 600 year old process which has evolved little, if any, in the last few hundred years although it was born from technology. Furthermore, the intaglio process relies on mental visualisation of the final artwork, making the real outcome and the planned outcome dissimilar. Students of intaglio printmaking are often surprised or disappointed by the printed result due to the lack of efficient planning. There are several ways in which software influences the creative process, including enhancing visualisation and communication, premature fixation, circumscribed thinking and bounded ideation. In this research, computer software is used as a simulator to facilitate the planning process in order to minimise the disconnect between visualisation and outcome, and serve as learning instrument. The use of digital computer technologies has been a highly debated issue in printmaking as there exists a rift between printmakers; those who embrace and explore new technologies and those who reject new methods in favour of traditional means. New technologies in printmaking offer exciting opportunities, both innovative and creative, but these new technologies are often seen as alternative or auxiliary methods of printmaking compared to traditional ways. Since these debates have been buried but not necessarily resolved, this study reinvigorates some of these perspectives and seeks a common middle ground. This study does not argue for, or against computer technology, but rather for a third paradigm: technology can coexist with intaglio without compromising the beauty and authenticity of hand processes. Computer technologies, therefore, serve as a facilitator to amplify the traditional intaglio hand process. However, the issue of discussion in this thesis is not hybrid printmaking but rather a hybrid mode of thinking in the printmaking discipline. This iterative design experiment consists of a written dissertation and intaglio printed artworks which inform and complement each other. The theoretical foundation of the art practice is found in the Bauhaus slogan: “Art and technology: a new unity”. Art and technology form the basis of the theory and the theme of entropy – the process of degeneration – is illustrated in the design artefacts. This theme shows process and illustrates the idea of a positive agent: the interference of computer in intaglio to instil new energy and value not only to keep it alive, but position it as an important skill necessary for growth in the knowledge-based economy. Furthermore, this study contributes to the scholarly discussion of design’s conceptual skills (ways of thinking) in order to enhance production capabilities (ways of making).

La microscopie confocale de réflectance in-vivo (RCM) est un outil puissant pour visualiser les couches cutanées à une résolution cellulaire. Des descripteurs du vieillissement cutané ont été mis en évidence à partir d'images confocales. Cependant, leur évaluation nécessite une analyse visuelle des images par des dermatologues expérimentés. L'objectif de cette thèse est le développement d'une technologie innovante pour quantifier automatiquement le phénomène du vieillissement cutané en utilisant la microscopie confocale de réflectance in vivo. Premièrement, la quantification de l’état de l’épiderme est abordée. Ensuite, la jonction dermique-épidermique est segmentée, et sa forme est caractérisée. Les mesures proposées mettent en évidence une différence significative entre les groupes d'âge et l’exposition au soleil. Enfin, les méthodes proposées sont validées par des études cliniques et d'efficacité de produits cosmétiques<br>In-vivo reflectance confocal microscopy (RCM) is a powerful tool to visualize the skin layers at cellular resolution. Aging descriptors have been highlighted from confocal images. However, it requires visual assessment of images by experienced dermatologists to assess those descriptors. The objective of this thesis is the development of an innovative technology to automatically quantify the phenomenon of skin aging using in vivo reflectance confocal microscopy. First, the quantification of the epidermal state is addressed. Then, the Dermal-Epidermal Junction is segmented, and its shape is characterized. The proposed measurements show significant difference among groups of age and photo-exposition. Finally, the proposed methods are validated through both clinical and cosmetic product efficacy studies

Un aéronef à voilure tournante est un système physique dynamique complexe. Le développement de ce type de système nécessite méthodes d’analyse (structurelle et comportementale) et de commande afin de maîtriser ses comportements. L’approche énergétique (bond graph et formalisme hamiltonien à port) permet une représentation multi-physique non linéaire, modulaire (acausale) et à différents niveaux de granularité. Parmi ses organes, les commandes de vol de l’aéronef permettent la transmission du pilotage aux rotors : canaliser la puissance motrice (2 MW) à partir d’une commande manuelle est impossible sans organes actifs d’assistance. Afin de représenter les cheminements et traitements des informations nécessaires aux organes actifs, la représentation multi-physique est complétée par une représentation informationnelle causale (schéma bloc).Les travaux exposés dans ce mémoire visent à ajouter le niveau de granularité intermédiaire et nécessaire entre la représentation multi-physique pure et une représentation combinée physique et informationnelle. Basée sur la démarche du PMBC (Physical Model Based Control), ils proposent une méthode originale permettant de représenter les organes d’assistance et leur commande par un modèle physique équivalent. La méthode est ici enrichie dans une démarche de conception des Systèmes d’Assistance à Opérateur : nous déterminons où doivent agir les organes actifs, selon quelles mesures et suivant quelles lois de commande. La méthode est illustrée sur un cas d’étude industriel : nous obtenons deux représentations de l’espace des solutions (les représentations physico-informationnelle détaillée et globale de son comportement) incluant la solution industrielle actuelle<br>A rotorcraft is a complex dynamic physical system. The development of this kind of systems requires methods to analyze its structure and its behavior and to control this latter. The energetic framework (bond graph and Hamiltonian formulation) allows a multiphysical nonlinear representation, modular and with several levels of granularity. Among its components, flight controls transmit the orders from the pilot to rotors. Leading the motive power (about 2MW) directly from a handling control is almost impossible without active devices for assistance. In order to represent the flow of the control information and its processing, a cyberphysical representation combines a multiphysical representation with an informational representation (bloc diagram).This thesis work aims at proposing an intermediate granularity level between purely multiphysical representations and cyberphysical representations. Based on PMBC (Physical Model Based Control) approach, a new method to represent the assistance parts is proposed, by means of a physical equivalent model. The method is then enriched by a genuine design procedure of an Operator Assisting System: we determine where actuators must operate, according to which control laws and from which measurements. The method is applied to an industrial case: two representations of the possible design solutions set are obtained, a detailed cyberphysical representation and a global representation of its behavior. The actual industrial solution belongs to the defined set of possible solutions

Facial expression recognition has become an active research topic in recent years due to its applications in human computer interfaces and data-driven animation. In this thesis, we focus on the problem of how to e?ectively use domain, temporal and categorical information of facial expressions to help computer understand human emotions. Over the past decades, many techniques (such as neural networks, Gaussian processes, support vector machines, etc.) have been applied to facial expression analysis. Recently graphical models have emerged as a general framework for applying probabilistic models. They provide a natural framework for describing the generative process of facial expressions. However, these models often su?er from too many latent variables or too complex model structures, which makes learning and inference di±cult. In this thesis, we will try to analyze the deformation of facial expression by introducing some recently developed graphical models (e.g. latent topic model) or improving the recognition ability of some already widely used models (e.g. HMM). In this thesis, we develop three di?erent graphical models with di?erent representational assumptions: categories being represented by prototypes, sets of exemplars and topics in between. Our ¯rst model incorporates exemplar-based representation into graphical models. To further improve computational e±- ciency of the proposed model, we build it in a local linear subspace constructed by principal component analysis. The second model is an extension of the recently developed topic model by introducing temporal and categorical information into Latent Dirichlet Allocation model. In our discriminative temporal topic model (DTTM), temporal information is integrated by placing an asymmetric Dirichlet prior over document-topic distributions. The discriminative ability is improved by a supervised term weighting scheme. We describe the resulting DTTM in detail and show how it can be applied to facial expression recognition. Our third model is a nonparametric discriminative variation of HMM. HMM can be viewed as a prototype model, and transition parameters act as the prototype for one category. To increase the discrimination ability of HMM at both class level and state level, we introduce linear interpolation with maximum entropy (LIME) and member- ship coe±cients to HMM. Furthermore, we present a general formula for output probability estimation, which provides a way to develop new HMM. Experimental results show that the performance of some existing HMMs can be improved by integrating the proposed nonparametric kernel method and parameters adaption formula. In conclusion, this thesis develops three di?erent graphical models by (i) combining exemplar-based model with graphical models, (ii) introducing temporal and categorical information into Latent Dirichlet Allocation (LDA) topic model, and (iii) increasing the discrimination ability of HMM at both hidden state level and class level.<br>published_or_final_version<br>Computer Science<br>Doctoral<br>Doctor of Philosophy