We describe a conceptual architecture and software implementation specific to the task of interpretation, summarization, visualization, explanation, and interactive exploration of time-oriented clinical data and the multiple levels of meaningful concepts that can be abstracted from these data. We build on our work on abstraction of timeoriented clinical data using a knowledge base, acquired from clinical experts, of temporal properties of the data. We call the new framework KNAVE (Knowledge-based Navigation of Abstractions for Visualization and Explanation). The visualization and exploration operators, whose semantics are domain independent, access the domain-specific knowledge base. Exploration exploits key relations (e.g., the abstraction hierarchy) in each clinical domain. Preliminary assessment of the prototype with several clinical users has been encouraging. The KNAVE methodology has broad ramifications for reducing the load that large numbers of time-oriented clinical data put on practicing physicians.

We describe a new conceptual methodology and related computational architecture called Knowledge-based Navigation of Abstractions for Visualization and Explanation (KNAVE). KNAVE is a domain-independent framework specific to the task of interpretation, summarization, visualization, explanation, and interactive exploration, in a context-sensitive manner, of time-oriented raw data and the multiple levels of higher-level, interval-based concepts that can be abstracted from these data. The KNAVE domain-independent exploration operators are based on the relations defined in the knowledge-based temporal-abstraction problem-solving method, which is used to abstract the data, and thus can directly use the domain-specific knowledge base on which that method relies. Thus, the domain-specific semantics are driving the domain-independent visualization and exploration processes, and the data is viewed through a filter of domain-specific knowledge. By accessing the domain-specific temporal-abstraction knowledge base and the domain-specific time-oriented database, the KNAVE modules enable users to query for domain-specific temporal abstractions and to change the focus of the visualization, thus reusing for a different task (visualization and exploration) the same domain model acquired for abstraction purposes. We focus here on the methodology, but also describe a preliminary evaluation of the KNAVE prototype in a medical domain. Our experiment incorporated seven users, a large medical patient record, and three complex temporal queries, typical of guideline-based care, that the users were required to answer and/or explore. The results of the preliminary experiment have been encouraging. The new methodology has potentially broad implications for planning, monitoring, explanation, and in...

Abstract—In common Web-based search interfaces, it can be difficult to formulate queries that simultaneously combine temporal, spatial, and topical data filters. We investigate how coordinated visualizations can enhance search and exploration of information on the World Wide Web by easing the formulation of these types of queries. Drawing from visual information seeking and exploratory search, we introduce VisGets – interactive query visualizations of Web-based information that operate with online information within a Web browser. VisGets provide the information seeker with visual overviews of Web resources and offer a way to visually filter the data. Our goal is to facilitate the construction of dynamic search queries that combine filters from more than one data dimension. We present a prototype information exploration system featuring three linked VisGets (temporal, spatial, and topical), and used it to visually explore news items from online RSS feeds. Index Terms—Information visualization, World Wide Web, information retrieval, exploratory search, visual information seeking. 1

In this paper we present the CyberNet research project. The aim of this project is to study how 3D visualization may help the user in the process of monitoring large amounts of dynamic information. The project focuses on a specific application domain, network management, but it is designed so that it can be applied to other domains. The paper presents how information is collected and structured in order to define services that the user wants to monitor. We also present the impact of the dynamic nature of information on the system. Each 3D world represents a service, that is a model that groups and structures all the information related to a specific aspect of the network. Each modification of the service has a real time impact on the virtual world. This representation is done within the context of a 3D metaphor that defines the rules used to map services onto graphical elements (layout managers and glyphs). It also defines how information is mapped onto the visual parameters (color, si...

When information visualization is being used to support multiple users, two characteristics are important. First, multiple users with different backgrounds have individual information needs and thus require multiple views on the information. Second, to allow users to experiment with the information and the visualization, the visualization must be adaptable. This paper presents a conceptual framework which decouples the generation and presentation of information by means of an intermediate derived model, allowing users to adapt the visualization to their information needs. Additionally, we will discuss a Web-based software architecture which deploys CORBA to allow for dynamic and interactive visualizations.

WebAware is a system that makes information about web site traffic available in a public space. The information is presented in a dynamic visualization, which is based on a map of the web site and designed to give an overview of how the site is constructed. Information about activity, such as the number of visitors and which area of the web site is most popular, is continuously reflected on the display. The application is designed to be shown on a wall-mounted public screen. Initial evaluations show that WebAware can act as an aesthetically pleasing information display, as well as a nice conversation piece.

The development of novel interactive visualizations can substantially contribute to environmental modeling and understanding of complex environmental processes. To allow the Web Map Service (WMS) to support this, this paper explores a generic framework in which a dynamic environmental modeling process can be interactively visualized, controlled and tuned on the Internet by using Java 3D-based hybrid Internet computation through the simulation steering technique. A hydrological model, TOPMODEL, is employed to illustrate the simulation of a rainfall-run off process within a computational and steering environment. This environment allows users to visually interact and experiment with environmental model computation, thereby facilitating the exploration of process-based environmental applications.

We describe a conceptual and computational architecture called Knowledge-based Navigation o f Abstractions for Visualization and Explanation (KNAVE). KNAVE is a domain-independent framework specific to the task of interpretation, summarization, visualization, explanation, and interactive navigation in a context-sensitive manner through time-oriented raw data and the multiple levels of higher-level, interval-based concepts that can be abstracted from these data. The KNAVE domain-independent navigation operators are mapped through the ontology of the knowledge-based temporal-abstraction problem-solving method to the domain-specific knowledge base. Thus, the domain-specific semantics are driving the domain-independent visualization and navigation processes. By accessing the domain-specific temporal-abstraction knowledge base and the domain-specific time-oriented database, the KNAVE modules enable users to query for domain-specific temporal abstractions and to change the focus of the visualization, thus reusing for a different task the domain model that has been acquired from the domain experts. Initial evaluation of the KNAVE prototype has been encouraging. The KNAVE methodology has potentially broad implications for tasks such as planning, monitoring, explanation, and data mining.

Visualization --- the transformation of data and information into multimedia including pictures, animation and 3D scenes --- enables users to understand information more naturally. It reveals patterns and relations in the information which may otherwise remain hidden. As a consequence, it can provide a single user with enough valuable information to support decision making. In addition to this, visualization can also be used to explain information to other people. In this case, the results of visualization are deployed as arguments in collaborative decision making. This paper discusses a distributed visualization architecture which supports collaborative decision making. The architecture is designed with the following consideration in mind: "multiple users, with different information needs, require multiple views or perspectives of the data." Additionally, in order to support the cooperation between users during the decision making process, we extend the architecture with collaborativ...

This paper introduces a framework for visualization in a distributed multi-user environment, which builds upon two important observations. First, multiple users with different backgrounds have individual information needs and thus require multiple views on the information. Second, to allow users to experiment with the information and the visualization, the visualization must be adaptable. To meet these requirements, the framework decouples the generation and presentation of information by means of an intermediate derived model, allowing users to adapt the visualization to their information needs. As a realization of the framework, we will discuss a Web-based software architecture which deploys CORBA to allow for dynamic and interactive visualizations. The distributed visualization architecture, DIVA, consists of generic software components reflecting the conceptual framework. Using Web-based standards, such as VRML and Java, the visualization can be deployed independently of the platf...