Dissertation, Publications, Jazz, Etc.
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Jul, S. (2007). Who’s Really on First? A Domain-Level User, Task and Context Analysis for Response Technology. Proceedings of the 4th International ISCRAM Conference. Delft, the Netherlands, May 2007.

This paper presents a domain-level user, task and context analysis for response technology, based on sociological studies of disaster and disaster response. The analysis examines three dimensions of disaster--scale, kind and anticipability--that have been linked to differences in response characteristics, including differences in individual and organizational responders and behaviors. It yields a number of implications for design, and reveals five domain-specific design requirements. It also offers systematic characterizations of users, tasks and contexts of response technology, that begin to structure the user interface design space, laying a foundation for a theory of design. This work provides a conceptual basis to help researchers and designers recognize and address possible limitations of design decisions, leading, ultimately, to more usable and effective response technologies.

Jul, S. (2004). From Brains to Branch Points: Cognitive Constraints in Navigational Design. PhD dissertation, University of Michigan, Computer Science and Engineering.

Jul, S. (2003). Pad vs. Leylines: Movement Model Matters.

This paper describes Predictive Targeted Movement (PTM) and reports on two experiments demonstrating its effectiveness. PTM is a constrained movement model that is defined in terms of cognitive concepts of navigation, such as location, destination and route. The exact definitions of these must be defined by the designer in accordance with the navigational needs of their design situation. PTM incorporates a notion of prediction that allows heuristic factors to be used in movement constraints. PTM has been applied to inter-object navigation in Jazz. Results from a study comparing PTM-based movement to a conventional movement model showed increased task performance, without increased error, and suggested that the physical and cognitive costs of navigation were reduced.

Jul, S. (2003). "This is a Lot Easier!": Constrained Movement Speeds Navigation. ACM Conference on Human-Factors in Computing Systems, CHI 2003.

This paper reports on an experiment comparing constrained and unconstrained movement in a 2D zooming environment. Results for a directed search task showed a significant decrease in time on task when movement was constrained, accompanied by considerable reductions in all mouse movement activity. Detailed analysis suggests that subjects were calmer, more confident in their actions and experienced less spatial disorientation, and indicates that judiciously constrained movement can reduce both mechanical and cognitive demands of navigating.

Jul, S., Quintana, C.(2003). Designing for Learning. ACM Conference on Human-Factors in Computing Systems, CHI 2003.

Jul, S. (2002). A Framework for Locomotional Design: Toward a Generative Design Theory. ACM Conference on Human-Factors in Computing Systems, CHI 2002 Extended Abstracts, 862-863.
Associated Poster.

Generative design theories are needed to bridge the gaps between pure scientific knowledge, individual ("point") designs and systematic generation of viable design alternatives.  This paper suggests a framework for locomotional design that uses knowledge of navigation and spatial cognition to inform design.  Examples of the implications of two such pieces of knowledge are sketched out, suggesting how this framework might lead to a generative design theory.

Jul, S. (2002). Predictive Targeted Movement in Electronic Spaces. ACM Conference on Human-Factors in Computing Systems, CHI 2002 Extended Abstracts, 626-627.

The lodestones and leylines interaction technique simplifies navigation in electronic spaces by coordinating physical and conceptual movement¾gently constraining motion to follow automatically computed paths to predicted destinations.  This approach simplifies physical movement, ensures that movement leads to interesting locations and supports navigation to locations not visible from the current location. It is illustrated in a spatial multiscale environment where pilot data show reliable performance improvements.

Jul, S. (2001). Locomotional Structure in Service of Wayfinding: A Partial Design Theory.

This paper introduces a partial theory of design for locomotion. The goal of the theory is to help generate actual designs by informing design content. Assuming that locomotion is always in service of the cognitive task of wayfinding, the theory relates cognitive constructs of wayfinding problem-solving and decision-making to features of locomotional design. Specifically, the theory suggests that the complexity of wayfinding reasoning is controlled, in part, by how closely the set of locations and ways of moving between them provided in the environment matches those necessitated by the user’s task.

The theory has been applied to the design of support for the task of moving between individual objects in a multiscale environment. The resulting lodestones and leylines design constrains locomotion based on inter-object geometry and uses an approximate indication of direction from the user to predict a target location and guide movement. Preliminary results of a pilot study indicate that this technique dramatically improves wayfinding performance over locomotional techniques based on geometry of the space itself.

Jul, S. (2000). Lodestones and Leylines: Gracefully Constraining Movement in Multiscale.

This paper introduces a technique to help users in a graphic multiscale environment move between locations of interest faster and prevent them from getting lost. The technique constrains movement to direct paths between salient objects or views of objects. Based on an indication of approximate direction from the user, the system predicts the desired destination, and then uses this prediction to compute a path and guide movement. Using this technique, users perform fewer physical actions and experience less disorientation.

Jul, S. (2000). Lodestones and Leylines: Designing Locomotion in a Personal File System.

We report on an exercise intended to help articulate constraints on locomotion and their implications for design. The assumption that locomotion is in service of navigation leads us to consider both cognitive and mechanical constraints. The exercise is to design support for accessing files in a hierarchical file system in the course of ordinary computer-based work. Characterizing the design situation in terms of four possible sources of locomotional constraints (the navigator, the task, the environment and the circumstances) leads to an abstract design of a dynamic locomotional mechanism that provides rapid accurate access to a small set of files. Applying this abstract design in Microsoft Windows™ and Jazz yields two quite different specific designs. The exercise results in a broad organization of the factors that constrain locomotion into three categories: Locomotional mechanism, Navigational resources and Navigational effect.

Jul, S. (1999). View-Based Animation.

We present a technique for animating objects that is based on the concept of viewpoint rather than on time. Object properties are computed as a function of the viewpoint. The viewpoint, in turn, is controlled manually or is programmed to change as a function of time. This allows objects in a fly-through or zooming interface to be animated selectively. The speed of the animation is controlled by the viewer, and the animation can be run forwards or backwards and can be stopped, started and stepped by manipulating the view controls. This technique is not intended to replace time-based animation, but is rather to be used in special cases or in conjunction with time-based animation.

Jul, S. (1999). Research Agenda: A Unifying Theory of Frames of Reference. Position Paper, NCGIA workshop on Multiple Modalities and Multiple Frames of Reference for Spatial Knowledge, Feb. 18-20, 1999.

Jul, S., Furnas, G. W. (1998). Critical Zones in Desert Fog: Aids to Multiscale Navigation. ACM Symposium on User Interface Software and Technology, UIST 98, 97-107.

In this paper, we introduce the problem of “desert fog,” a condition wherein a view of an information world contains no information on which to base navigational decisions. We present a set of view-based navigational aids that allow navigators to find their way through desert fog in multiscale electronic worlds. Prototypes of these aids have been implemented in the Landmarking and ZTracker systems. We introduce the concept of critical zone analysis, a method of grouping objects according to their visibility in views of the information world rather than their spatial layout. This concept was derived from a formal analysis of desert fog using view-navigation theory. Our analysis informally extends view-navigation theory to accommodate spatial multiscale worlds and is detailed in the paper.

Jul, S. (1998). Computational Implications of Human Navigation in Multiscale Electronic Worlds. ACM Conference on Human-Factors in Computing Systems, CHI 98 Summary, 56-57.

In this work I seek to formulate a theory of the computational implications of certain factors that affect human navigation in multiscale electronic worlds. Specifically, I seek to describe the properties a multiscale world must satisfy to furnish useful frames of reference. I draw factors from three areas. First, understanding of spatial cognition in general and frames of reference in spatial cognition in particular. Second, theoretical characteristics of multiscale information spaces. Third, general attributes of users' task contexts. The ultimate goal of the work is to provide a basis for a theory of design of navigational aids. This project also seeks to provide a case study of integrating existing psychological theories with emerging theories of computational environments.

Jul, S. (1998). Flying Logos through Scale.

We explore a set of techniques that allow visual transitions in presentations to be animated by specifying scale rather than time constraints. These are not traditional animations that are perceived by moving pieces of the animation past the viewer. Rather, they are perceived by moving the viewer through pieces of the animation. This allows the pacing and timing to be governed by the interaction controls and, hence, the presenter, rather than being a fixed characteristic of the animation. Since animations exist independently of time they may be entered, paused or exited at arbitrary points, and can be viewed “forward” as well as “backward.” They are implemented as behaviors attached to arbitrary objects, so may be combined or reused simply by moving or copying objects.

Jul, S., Furnas, G. W. (1997). Navigation in Electronic Worlds. SIGCHI Bulletin, 29, 4 (Oct), 44-49.

This report summarizes a workshop at CHI 97 that focused on issues in navigation in electronic information environments. In addition to trying to clarify definitions of navigation and related concepts, the workshop explored aspects of the psychology of navigation, navigation as a task and properties of worlds (and their content) that affect in how and whether people can find their way around. The workshop also began to explore interactions between tasks, the navigator, the world that is navigated and the content of that world. The workshop drew participants from a broad variety of backgrounds allowing discussion from psychological, theoretical and design perspectives.

Watts, L., Jul, S. (1997). A Meeting of Research Minds. SIGCHI Bulletin, 29, 4 (Oct), 30-33.

At CHI '92 in Monterey, California, a number of researchers from the CHI community got together for the first time at a special event called the Basic Research Symposium. The idea behind this event was to provide a forum explicitly dedicated to fundamental issues in generating new CHI knowledge. There has been a Basic Research Symposium associated with every CHI conference since that time and, although the event has evolved somewhat over its five subsequent iterations, it has remained true to this objective.

The authors chaired this year's Basic Research Symposium, held on Saturday 22nd and Sunday 23rd of March, in Atlanta, Georgia, prior to the CHI 97 Conference on Human Factors in Computing Systems. This year, for the first time, it was included as a workshop in the formal pre-conference programme. This article is intended to give the reader a flavour of what the BRS is all about. It will look at how the 1997 event was put together and report back to the wider CHI community some of the issues that were discussed as challenges for HCI research.

Jul, S. (1997). Landmarking and Navigability. Position Paper, CHI 97 Workshop on Navigation in Electronic Worlds.

In my current work, I focus on the identification of particularly interesting locations in a spatial information world and the introduction of landmarks -- either designated information objects or explicitly introduced navigational objects -- to guide navigation relative to these location. This work explores a means of increasing the navigability of an information world by decreasing the amount of information necessary and available to the navigator. Selection of interesting locations is based on the information content of the world without assuming that the information itself has any particular structure other than that implied by its spatial layout.

Jul, S. (1996). Bringing HcI and hCI Together. Position Paper, CHI 96 Basic Research Symposium.

My research seeks to begin to develop an applied engineering science based on the theory and practice of HCI by deriving domain-specific application frameworks from knowledge of end-user needs. The goal of the research is to make it easy to design and build "good" applications and difficult to build "bad" ones by adhering to human-centric criteria for quality. In the process, I hope to create a common ground between those HCI professionals who focus more on the Human side and those who focus more on the Computer side of human-computer interaction.

Jul, S., Klein, J., Jackson, S., Soloway, E. (1996). Designing for Multiple User Groups: Lessons Learned from Developing Research Software for the Classroom.

In designing educational research software for the classroom, we discover three distinct user groups whose needs must be considered: students, teachers and researchers. Our experience is that despite employing user-centered design practices, our software tends to fail in its overall purpose if all three groups are not considered. To illustrate this conclusion we examine three projects, PlanIt Out, RiverBank and Model-It, as case studies of user-centered design processes. All had competent staffing and followed standard design practices yet two failed in their overall goals as a consequence of failing to consider the existence of multiple user groups.

This analysis leads us to conclude that traditional design practices tend to fall short in domains that involve multiple user groups, and that special methodologies for analysis of user groups need to be developed. We find that the relevant groups in multiple-user-group design can be identified and characterized in terms of distinct needs and relationships between groups. We develop a small taxonomy for identifying multiple-user-group situations, and suggest that user group analysis must include steps for identifying the relevant groups, determining relationships between groups, and identifying and resolving potential conflicts in the goals for each group.

Last updated: 24-Apr-2007