Information visualizations must often be custom programmed to support complex user tasks and database schemas. This is an expensive and time consuming effort, even when general-purpose visualizations are utilized within the solution. This research introduces the Snap visualization server and system architecture that addresses limitations of previous Snap-Together Visualization research and satisfies the need for flexibility in information visualizations. An enhanced visualization model is presented that formalizes multiple-view visualization in terms of the relational data model. An extensible architecture is introduced that enables flexible construction and component integration. It allows the integration of diverse data, letting users spend less time massaging the data prior to visualization. The web-based server enables universal access, easy distribution, and the ability to intermix and exploit existing components. This web-based software architecture provides a strong foundation for future multiple-view visualization development. / Master of Science

Multi-resolution visualization (MRV) systems are widely used for handling large amounts of information. These systems look different but they share many common features. The visualization research community lacks a general framework that summarizes the common features among the wide variety of MRV systems in order to help in MRV system design, analysis, and enhancement. This dissertation proposes such a general framework. This framework is based on the definition that a MRV system is a visualization system that visually represents perceptions in different levels of detail and allows users to interactively navigate among the representations. The visual representations of a perception are called a view. The framework is composed of two essential components: view simulation and interactive visualization. View simulation means that an MRV system simulates views of non-existing perceptions through simplification on the data structure or the graphics generation process. This is needed when the perceptions provided to the MRV system are not at the user's desired level of detail. The framework identifies classes of view simulation approaches and describes them in terms of simplification operators and operands (spaces). The simplification operators are further divided into four categories, namely sampling operators, aggregation operators, approximation operators, and generalization operators. Techniques in these categories are listed and illustrated via examples. The simplification operands (spaces) are also further divided into categories, namely data space and visualization space. How different simplification operators are applied to these spaces is also illustrated using examples. Interactive visualization means that an MRV system visually presents the views to users and allows users to interactively navigate among different views or within one view. Three types of MRV interface, namely the zoomable interface, the overview + context interface, and the focus + detail interface, are presented with examples. Common interaction tools used in MRV systems, such as zooming and panning, selection, distortion, overlap reduction, previewing, and dynamic simplification are also presented. A large amount of existing MRV systems are used as examples in this dissertation, including several MRV systems developed by the author based on the general framework. In addition, a case study that analyzes and suggests possible improvements for an existing MRV system is described. These examples and the case study reveal that the framework covers the common features of a wide variety of existing MRV systems, and helps users analyze and improve existing MRV systems as well as design new MRV systems.

This work presents our research into visualization for digital repository search interfaces, motivated by the prevalence of existing hierarchical data structures and the general lack of contextualization present in existing systems. We develop the ResultMap concept, a treemap-based visualization that we have applied to keyword search engine and faceted classification data environments, and present the results of their empirical evaluation, which show limited objective and subjective benefits for some users and no detrimental effects in any cases. We organize this work as follows: Chapter 1 provides an introduction to our problem area, motivates our general approach of leveraging hierarchical structure (via ResultMaps) for context, and proposes a thesis statement and corresponding research questions. Chapter 2 discusses related work, and includes a survey and design characterization of faceted navigation tools. Chapter 3 defines the key visual and interactive features of the ResultMap concept and justifies their basic design. Chapter 4 presents our implementation and evaluation of ResultMaps applied to digital library search engine result pages (SERPs). Chapter 5 consists of two major portions: a presentation of formal data and query models for faceted environments, and our implementation and evaluation of ResultMaps in a faceted UI context. In Chapter 6 we conclude--based on our results from Chapter 4 and Chapter 5--with a set of principles for designing both visual search interfaces themselves and designing their evaluation. We finish with suggestions for future research in this area.

Today e-commerce retailers use large warehouses to store goods before they are sold and shipped. One of the main performance issues for Apotea AB, an online pharmacy based in Sweden, is that the staffers who walk around in the warehouse often are delayed in queues or clusters, usually as a result of missing items or difficulties finding items. This paper describes how, based on sparse data, a map-based interactive visualization was created to aid staffers in their task of evaluating how so called pick lists perform. The visualization was evaluated using UMUX-LITE [20] and a grounded model of NOvice’s information VIsualization Sensemaking (NOVIS-model) [17]. Results showed an overall successful design. The main affordance of the visualization was that it showed warehouse performance over time when animation speed was set to maximum, this was enabled by sliders and buttons. The main limitations were found to be a lack of intermediary level of visualization (e.g. heat map overview of an hour) in the visualization and that there was no higher level of data, e.g. incident data, which could be visualized. These limitations represent the core of what this paper identifies as future work.

published_or_final_version / Industrial and Manufacturing Systems Engineering / Master / Master of Philosophy

Um sensor ou biossensor é um dispositivo analítico que tem por objetivo principal a identificação de substâncias e suas concentrações. O emprego efetivo dos sensores permite resolver diversos problemas em várias áreas como química, biologia, medicina, farmacologia, ciências ambientais, entre outras. Dentre desses problemas podemos ressaltar dois: o diagnóstico de doenças e a substituição de seres humanos por línguas eletrônicas para evitar as análises subjetivas. O primeiro problema é resolvido pela identificação de molécula única mas apresenta problemas relacionados a grande quantidade de dados gerados pelos sensores Surface Enhanced Raman Spectroscopy (SERS). Já o segundo problema envolve a recalibração de sensores de espectroscopia de impedância para que possam ser substituídos em línguas eletrônicas quando apresentem deficiências. Em ambos casos foram desenvolvidas abordagens que empregaram técnicas de visualização de informação e permitem uma exploração eficiente da grande quantidade de dados produzidos. A primeira abordagem conseguiu melhorar o tempo de execução do processo de detecção de molécula única em contrapartida a análise manual atualmente empregada além de reduzir o número de falsos positivos. A segunda abordagem, a troca de sensores em línguas eletrônicas, mostrou resultados satisfatórios. O uso da definição do circuito eletrônico equivalente de Taylor em combinação com Generalized Procrustes Analysis (GPA) permitiu de forma adequada a troca de sensores por conseguir transformar a resposta de um sensor na resposta do outro, característica que no futuro poderá ser usada para conseguir produzir sistemas mais reprodutíveis e confiáveis / A sensor or biosensor is an analytical device that aims to identify substances and their concentrations. The efficient employment of sensors allows the solution of many problems in several fields such as chemistry, biology, medicine, pharmacology, environmental sciences, among others. Two problems were the main focus of this master\'s thesis: the diagnosis of diseases and the replacement of human beings by electronic tongues to avoid subjective analysis. The first problem is solved using single molecule detection but presents problems related to the large amount of data generated by sensors Surface Enhanced Raman Spectroscopy (SERS). The second one involves the recalibration of impedance spectroscopy sensors in electronic tongues for them to be replaced when one of them presents defficiencies. We have developed two different approaches to handle these problems, both of them involve information visualization methods making the exploration of large amounts of data more efficiently. The first approach improved the execution time of the single molecule detection process compared to the manual analysis. The number of spectra classified as false positives was also reduced. The second approach, which is a candidate solution to the replacement of sensors in an electronic tongue, employs the definition of the equivalent circuit of Taylor along with Generalized Procrustes Analysis (GPA) to achieve the desired goal. This leads to the recalibration of one sensor into the response of another one, presenting good results. In the future, this could be potentially used to produce more reliable and reproducible systems

Devido ao crescimento acelerado da quantidade de dados disponíveis para análise hoje, é comum lidar com grandes conjuntos de dados, por vezes complexos demais para serem interpretados na sua forma bruta. Por isso, as técnicas de Visualização de Informação têm o objetivo de facilitar para o ser humano a tarefa de análise e interação dos dados por meio da sua abstração em forma gráfica. Justificado pela necessidade de dar autonomia ao usuário final na criação de visualizações, este trabalho pretende delinear a importância da participação do usuário na criação e suporte à abstração da informação em forma gráfica. Para isso, foi desenvolvido o InterVis um sistema para criação interativa de visualizações de informação a partir de dados dinâmicos, que visa a permitir que o usuário final possa gerar e editar visualizações de acordo com a sua necessidade, independentemente da natureza da informação que deve ser analisada. O sistema foi testado utilizando o questionário USE a fim de verificar se a criação interativa de visualizações de informação, sem programação, aliada ao conhecimento do usuário sobre o domínio da aplicação, é mais eficiente da perspectiva da usabilidade sem perda significativa de flexibilidade. Os testes envolveram a execução de tarefas por indivíduos de um grupo de usuários. Todos os usuários conseguiram realizar todas as tarefas de criação e exploração em tempo hábil e avaliaram positivamente o sistema, além de terem sugerido diversas melhorias e novas funcionalidades. É possível concluir que o InterVis atualmente já atende às expectativas iniciais do trabalho, ainda que haja pontos a serem aprimorados em trabalhos futuros / Because of the growing amount of data available for analysis today, it is common to deal with large data sets, often too complex to be interpreted in their brute form. That is why Information Visualization techniques exist, to facilitate the analysis and interaction with data by humans through graphical abstractions. Motivated by the need to allow end users the autonomy to generate and edit visualizations, this work aims to underscore the importance of end user participation in the creation and support of these graphical abstractions of data. For this purpose, it was developed a system for interactive creation of Information Visualizations based on dynamic data, which aims to allow the final user to generate e edit visualizations according to their need and independently of the nature of the information that should be analyzed. This system was tested using the USE questionnaire, to verify whether this interactive creation of Information Visualizations, without programming, allied to the user knowledge of each applications domain, will be more efficient from the perspective of usability without significant loss of flexibility, as expected. The tests were compound of the tasks execution by individuals of a users group. All the users were able to conclude all tasks of creation and exploration in due time and evaluated positively the system, besides they have been suggested diverse improvement and new functionalities. It is possible to conclude that InterVis already fulfills the initial expectations of this work, although there are still points to be refined in future work

University of Macau / Faculty of Science and Technology. / Department of Computer and Information Science

Since the completion of the Human Genome Project in 2003, biologists have become exceptionally good at producing data. Indeed, biological data has experienced a sustained exponential growth rate, putting effective and thorough analysis beyond the reach of many biologists. This thesis presents BioBridge, an interactive visualization tool developed to bring intuitive data exploration to biologists. BioBridge is designed to work on omics style tabular data in general and thus has broad applicability. This work describes the design and evaluation of BioBridge's Entity View primary visualization as well the accompanying user interface. The Entity View visualization arranges glyphs representing biological entities (e.g. genes, proteins, metabolites) along with related text mining results to provide biological context. Throughout development the goal has been to maximize accessibility and usability for biologists who are not computationally inclined. Evaluations were done with three informal case studies, one of a metabolome dataset and two of microarray datasets. BioBridge is a proof of concept that there is an underexploited niche in the data analysis ecosystem for tools that prioritize accessibility and usability. The use case studies, while anecdotal, are very encouraging. These studies indicate that BioBridge is well suited for the task of data exploration. With further development, BioBridge could become more flexible and usable as additional use case datasets are explored and more feedback is gathered.

Many individuals with low health literacy (LHL) and limited English proficiency (LEP) have poor experiences consuming health information: they find it unengaging, unappealing, difficult to understand, and un-motivating. These negative experiences may blunt, or even sabotage, the desired effect of communicating health information: to increase engagement and ability to manage health. It is imperative to find solutions to improve poor experiences of health information, because such experiences heighten vulnerability to poor health outcomes. We aimed to address a gap in the health literacy literature by studying the patient experience of health information and how visualization might be able to help. Our four studies involved patients presented with health information in various settings to improve understanding and management of their care. We used semi-structured interviews and observations to understand patient experiences of receiving personal health information in the hospital. We learned that the return of results is desired and has the potential to promote patient engagement with care. We developed a novel method to analyze LHL, LEP caregiver experience and information needs in the community setting. The novel method increased our understanding and ability to detect differences in experiences within the same ethnic group, based on language preference. Next, we interrogated the literature for a solution to easily communicate complicated health information to disinterested, LHL, LEP individuals. We found that visualizations can help increase interest, comprehension, support faster communication, and even help broach difficult topics. Finally, our findings were used to develop a novel prototype to improve experiences of consuming genetic risk information for those having LHL and LEP. Unlike traditional approaches that focus on communicating risk numbers and probabilities, the novelty of our approach was that we focused on communicating risk as a feeling. We achieved this by leveraging vicarious learning via real patient experience materials (e.g., quotes, videos) and empathy with an emotive relational agent. We evaluated and compared the prototype to standard methods of communicating genetic risk information via a mixed methods approach that included surveys, questionnaires, interviews, observations, image analysis, and facial analysis. Main outcome variables were perceived ease of understanding, comprehension, emotional response, and motivation. We employed t-tests, ANOVAs, directed content analysis, correlation, regression, hierarchical clustering, and Chernoff faces to answer the research questions. All variables were significantly different for the prototype compared to the standard method, except for motivation as rated by 32 LHL, LEP community members. Findings revealed that LHL, LEP individuals have difficulty appropriately processing standard methods of communicating risk information, such as risk numbers supported by visual aids. Further, appealing visuals may inappropriately increase confidence in understanding of information. Visualizations affected emotions, which influenced perceived ease of understanding and motivation to take action on the information. Comprehension scores did not correlate with perceived ease of understanding, emotional response, or motivation. Findings suggest that providing access to comprehensible health information may not be enough to motivate patients to engage with their care; providing a good experience (taking into account the aesthetics and emotional response) of health information may be essential to optimize outcomes.