Search improvement within the geospatial web in the context of spatial data infrastructures

El trabajo desarrollado en esta tesis doctoral demuestra que es posible mejorar la búsqueda en el contexto de las Infraestructuras de Datos Espaciales mediante la aplicación de técnicas y buenas prácticas de otras comunidades científicas, especialmente de las comunidades de la Web y de la Web Semántica (por ejemplo, Linked Data). El uso de las descripciones semánticas y las aproximaciones basadas en el contenido publicado por la comunidad geoespacial pueden ayudar en la búsqueda de información sobre los fenómenos geográficos, y en la búsqueda de recursos geoespaciales en general. El trabajo comienza con un análisis de una aproximación para mejorar la búsqueda de las entidades geoespaciales desde la perspectiva de geocodificación tradicional. La arquitectura de geocodificación compuesta propuesta en este trabajo asegura una mejora de los resultados de geocodificación gracias a la utilización de diferentes proveedores de información geográfica. En este enfoque, el uso de patrones estructurales de diseño y ontologías en esta aproximación permite una arquitectura avanzada en términos de extensibilidad, flexibilidad y adaptabilidad. Además, una arquitectura basada en la selección de servicio de geocodificación permite el desarrollo de una metodología de la georreferenciación de diversos tipos de información geográfica (por ejemplo, direcciones o puntos de interés). A continuación, se presentan dos aplicaciones representativas que requieren una caracterización semántica adicional de los recursos geoespaciales. El enfoque propuesto en este trabajo utiliza contenidos basados en heurísticas para el muestreo de un conjunto de recursos geopesaciales. La primera parte se dedica a la idea de la abstracción de un fenómeno geográfico de su definición espacial. La investigación muestra que las buenas prácticas de la Web Semántica se puede reutilizar en el ámbito de una Infraestructura de Datos Espaciales para describir los servicios geoespaciales estandarizados por Open Geospatial Consortium por medio de geoidentificadores (es decir, por medio de las entidades de una ontología geográfica). La segunda parte de este capítulo desglosa la aquitectura y componentes de un servicio de geoprocesamiento para la identificación automática de ortoimágenes ofrecidas a través de un servicio estándar de publicación de mapas (es decir, los servicios que siguen la especificación OGC Web Map Service). Como resultado de este trabajo se ha propuesto un método para la identificación de los mapas ofrecidos por un Web Map Service que son ortoimágenes. A continuación, el trabajo se dedica al análisis de cuestiones relacionadas con la creación de los metadatos de recursos de la Web en el contexto del dominio geográfico. Este trabajo propone una arquitectura para la generación automática de conocimiento geográfico de los recursos Web. Ha sido necesario desarrollar un método para la estimación de la cobertura geográfica de las páginas Web. Las heurísticas propuestas están basadas en el contenido publicado por os proveedores de información geográfica. El prototipo desarrollado es capaz de generar metadatos. El modelo generado contiene el conjunto mínimo recomendado de elementos requeridos por un catálogo que sigue especificación OGC Catalogue Service for the Web, el estandar recomendado por deiferentes Infraestructuras de Datos Espaciales (por ejemplo, the Infrastructure for Spatial Information in the European Community (INSPIRE)). Además, este estudio determina algunas características de la Web Geoespacial actual. En primer lugar, ofrece algunas características del mercado de los proveedores de los recursos Web de la información geográfica. Este estudio revela algunas prácticas de la comunidad geoespacial en la producción de metadatos de las páginas Web, en particular, la falta de metadatos geográficos. Todo lo anterior es la base del estudio de la cuestión del apoyo a los usuarios no expertos en la búsqueda de recursos de la Web Geoespacial. El motor de búsqueda dedicado a la Web Geoespacial propuesto en este trabajo es capaz de usar como base un motor de búsqueda existente. Por otro lado, da soporte a la búsqueda exploratoria de los recursos geoespaciales descubiertos en la Web. El experimento sobre la precisión y la recuperación ha demostrado que el prototipo desarrollado en este trabajo es al menos tan bueno como el motor de búsqueda remoto. Un estudio dedicado a la utilidad del sistema indica que incluso los no expertos pueden realizar una tarea de búsqueda con resultados satisfactorios

Supporting exploratory browsing with visualization of social interaction history

This thesis is concerned with the design, development, and evaluation of information visualization tools for supporting exploratory browsing. Information retrieval (IR) systems currently do not support browsing well. Responding to user queries, IR systems typically compute relevance scores of documents and then present the document surrogates to users in order of relevance. Other systems such as email clients and discussion forums simply arrange messages in reverse chronological order. Using these systems, people cannot gain an overview of a collection easily, nor do they receive adequate support for finding potentially useful items in the collection. This thesis explores the feasibility of using social interaction history to improve exploratory browsing. Social interaction history refers to traces of interaction among users in an information space, such as discussions that happen in the blogosphere or online newspapers through the commenting facility. The basic hypothesis of this work is that social interaction history can serve as a good indicator of the potential value of information items. Therefore, visualization of social interaction history would offer navigational cues for finding potentially valuable information items in a collection. To test this basic hypothesis, I conducted three studies. First, I ran statistical analysis of a social media data set. The results showed that there were positive relationships between traces of social interaction and the degree of interestingness of web articles. Second, I conducted a feasibility study to collect initial feedback about the potential of social interaction history to support information exploration. Comments from the participants were in line with the research hypothesis. Finally, I conducted a summative evaluation to measure how well visualization of social interaction history can improve exploratory browsing. The results showed that visualization of social interaction history was able to help users find interesting articles, to reduce wasted effort, and to increase user satisfaction with the visualization tool

Spatial Hypermedia as a programming environment

This thesis investigates the possibilities opened to a programmer when their programming environment not only utilises Spatial Hypermedia functionality, but embraces it as a core component. Designed and built to explore these possibilities, SpIDER (standing for Spatial Integrated Development Environment Research) is an IDE featuring not only traditional functionality such as content assist and debugging support but also multimedia integration and free-form spatial code layout. Such functionality allows programmers to visually communicate aspects of the intent and structure of their code that would be tedious—and in some cases impossible—to achieve in conventional IDEs. Drawing from literature on Spatial Memory, the design of SpIDER has been driven by the desire to improve the programming experience while also providing a flexible authoring environment for software development. The programmer’s use of Spatial Memory is promoted, in particular, by: utilising fixed sized authoring canvases; providing the capacity for landmarks; exploiting a hierarchical linking system; and having well defined occlusion and spatial stability of authored code. The key challenge in implementing SpIDER was to devise an algorithm to bridge the gap between spatially expressed source code, and the serial text forms required by compilers. This challenge was met by developing an algorithm that we have called the flow walker. We validated this algorithm through user testing to establish that participants’ interpretation of the meaning of spatially laid out code matched the flow walker’s implementation. SpIDER can be obtained at: https://sourceforge.net/projects/spatial-ide-research-spide

Overviews and their effect on interaction in the auditory interface.

PhDAuditory overviews have the potential to improve the quality of auditory interfaces. However, in order to apply overviews well, we must understand them. Specifically, what are they and what is their impact? This thesis presents six characteristics that overviews should have. They should be a structured representation of the detailed information, define the scope of the material, guide the user, show context and patterns in the data, encourage exploration of the detail and represent the current state of the data. These characteristics are guided by a systematic review of visual overview research, analysis of established visual overviews and evaluation of how these characteristics fit current auditory overviews. The second half of the thesis evaluates how the addition of an overview impacts user interaction. While the overviews do not improve performance, they do change the navigation patterns from one of data exploration and discovery to guided and directed information seeking. With these two contributions, we gain a better understanding of how overviews work in an auditory interface and how they might be exploited more effectively

The Use of Multiple Slate Devices to Support Active Reading Activities

Reading activities in the classroom and workplace occur predominantly on paper. Since existing electronic devices do not support these reading activities as well as paper, users have difficulty taking full advantage of the affordances of electronic documents. This dissertation makes three main contributions toward supporting active reading electronically. The first contribution is a comprehensive set of active reading requirements, drawn from three decades of research into reading processes. These requirements explain why existing devices are inadequate for supporting active reading activities. The second contribution is a multi-slate reading system that more completely supports the active reading requirements above. Researchers believe the suitability of paper for active reading is largely due to the fact it distributes content across different sheets of paper, which are capable of displaying information as well as capturing input. The multi-slate approach draws inspiration from the independent reading and writing surfaces that paper provides, to blend the beneficial features of e-book readers, tablets, PCs, and tabletop computers. The development of the multi-slate system began with the Dual-Display E-book, which used two screens to provide richer navigation capabilities than a single-screen device. Following the success of the Dual-Display E-book, the United Slates, a general-purpose reading system consisting of an extensible number of slates, was created. The United Slates consisted of custom slate hardware, specialized interactions that enabled the slates to be used cooperatively, and a cloud-based infrastructure that robustly integrated the slates with users' existing computing devices and workflow. The third contribution is a series of evaluations that characterized reading with multiple slates. A laboratory study with 12 participants compared the relative merits of paper and electronic reading surfaces. One month long in-situ deployments of the United Slates with graduate students in the humanities found the multi-slate configuration to be highly effective for reading. The United Slates system delivered desirable paper-like qualities that included enhanced reading engagement, ease of navigation, and peace-of-mind while also providing superior electronic functionality. The positive feedback suggests that the multi-slate configuration is a desirable method for supporting active reading activities

Visual analysis of anatomy ontologies and related genomic information

Challenges in scientific research include the difficulty in obtaining overviews of the large amount of data required for analysis, and in resolving the differences in terminology used to store and interpret information in multiple, independently created data sets. Ontologies provide one solution for analysis involving multiple data sources, improving cross-referencing and data integration. This thesis looks at harnessing advanced human perception to reduce the cognitive load in the analysis of the multiple, complex data sets the bioinformatics user group studied use in research, taking advantage also of users’ domain knowledge, to build mental models of data that map to its underlying structure. Guided by a user-centred approach, prototypes were developed to provide a visual method for exploring users’ information requirements and to identify solutions for these requirements. 2D and 3D node-link graphs were built to visualise the hierarchically structured ontology data, to improve analysis of individual and comparison of multiple data sets, by providing overviews of the data, followed by techniques for detailed analysis of regions of interest. Iterative, heuristic and structured user evaluations were used to assess and refine the options developed for the presentation and analysis of the ontology data. The evaluation results confirmed the advantages that visualisation provides over text-based analysis, and also highlighted the advantages of each of 2D and 3D for visual data analysis.Overseas Research Students Awards SchemeJames Watt Scholarshi

Content arrangement on large high-resolution displays: a PDF-reader

The advent of Large High Resolution Displays (LHRDs) enables new visualisation methods for data analysis. This allows users to replace virtual navigation with spatial navigation which leads to further challenges in arranging the content appropriately. Conventional applications are developed without considering these novel issues; thus they may have deficiencies to be used on LHRDs efficiently. For this purpose, we conduct this thesis with a focus on the content arrangement of PDF documents. The aim of this thesis is to design, implement and evaluate an interface for viewing PDF documents on LHRDs. After an extensive literature review, we conducted design workshops to elicit design concepts and received various inspiring suggestions. The most promising design ideas were implemented as a working prototype by using an existing open source PDF renderer. Finally, we evaluated our implementation in a collaborative sensemaking user study in terms of usability and performance. We examine the result of the evaluation study and present key influencing factors which might be useful for future applications on LHRDs

Relativistic effects on satellite navigation

Osnovna znanja o relativističkim utjecajima na satelitsku navigaciju objašnjena su usporedbom glavnih karakteristika Newtonovog i relativističkog prostora vremena te kratkim uvodom u metriku gravitacijskog polja. Post-Newtonova teorija relativnosti objašnjena je kao osnova pri numeričkoj obradi relativističkih utjecaja u području satelitske navigacije. Vrijeme, kao vrlo važan parametar u relativističkoj satelitskoj navigaciji, objašnjeno je kroz koordinatno i vlastito vrijeme te kroz terestičko vrijeme i problem sinkronizacije satova. Opisani su relativistički utjecaji: na kašnjenje vremena, na razliku vremena zbog različitosti gravitacijskog polja, na frekvenciju, na širenje satelitskog signala te zbog rotacije Zemlje, zbog ekscentričnosti putanje satelita i zbog ubrzanja satelita prema teoriji relativnosti. Dan je pregled relativističkih utjecaja na GPS, GLONASS, Galileo i BeiDou satelitske sustave.The base of knowledge of relativistic effects on satellite navigation is presented through comparison of the main characteristics of the Newtonian and the relativistic space time and by a short introduction of metric of a gravity field. Post-Newtonian theory of relativity is presented as a background in numerical treating of satellite navigation relativistic effects. Time as a crucial parameter in relativistic satellite navigation is introduced through coordinate and proper time as well as terrestrial time and clocks synchronization problem. Described are relativistic effects: on time dilation, on time differences because of the gravity field, on frequency, on path range effects, caused by the Earth rotation, due to the orbit eccentricity and because of the acceleration of the satellite in the theory of relativity. Overviews of treatment of relativistic effects on the GPS, GLONASS, Galileo and BeiDou satellite systems are given

Relativistic effects on satellite navigation

Osnovna znanja o relativističkim utjecajima na satelitsku navigaciju objašnjena su usporedbom glavnih karakteristika Newtonovog i relativističkog prostora vremena te kratkim uvodom u metriku gravitacijskog polja. Post-Newtonova teorija relativnosti objašnjena je kao osnova pri numeričkoj obradi relativističkih utjecaja u području satelitske navigacije. Vrijeme, kao vrlo važan parametar u relativističkoj satelitskoj navigaciji, objašnjeno je kroz koordinatno i vlastito vrijeme te kroz terestičko vrijeme i problem sinkronizacije satova. Opisani su relativistički utjecaji: na kašnjenje vremena, na razliku vremena zbog različitosti gravitacijskog polja, na frekvenciju, na širenje satelitskog signala te zbog rotacije Zemlje, zbog ekscentričnosti putanje satelita i zbog ubrzanja satelita prema teoriji relativnosti. Dan je pregled relativističkih utjecaja na GPS, GLONASS, Galileo i BeiDou satelitske sustave.The base of knowledge of relativistic effects on satellite navigation is presented through comparison of the main characteristics of the Newtonian and the relativistic space time and by a short introduction of metric of a gravity field. Post-Newtonian theory of relativity is presented as a background in numerical treating of satellite navigation relativistic effects. Time as a crucial parameter in relativistic satellite navigation is introduced through coordinate and proper time as well as terrestrial time and clocks synchronization problem. Described are relativistic effects: on time dilation, on time differences because of the gravity field, on frequency, on path range effects, caused by the Earth rotation, due to the orbit eccentricity and because of the acceleration of the satellite in the theory of relativity. Overviews of treatment of relativistic effects on the GPS, GLONASS, Galileo and BeiDou satellite systems are given