Lacome is a multi-user cross-platform system that supports collaboration in a shared large screen display environment. Lacome allows users to share their desktops or application windows using any standard VNC server. It supports multi-user concurrent interaction on the public shared display as well as input redirection so users can control each other's applications. La-come supports separate types of interaction through a Lacome client for window management tasks on the shared display(move, resize, iconify, de-iconify) and for application interactions through the VNC servers. The system architecture provides for Publishers that share information and Navigators that access information. A Lacome client can have either or both, and can initiate additional Publishers on other VNC servers that may not be Lacome clients. Explicit access control policies on both the server side the client side provide a flexible framework for sharing. The architecture builds on standard cross-platform components such as VNC and JRE. Interaction techniques used in the window manager ensure simple and transparent multi-user interactions for managing the shared display space. We illustrate the design and implementation of Lacome and provide insights from initial user experience with the system.

Lacome is a multi-user cross-platform system that supports collaboration in a shared large screen display environment. Lacome allows users to share their desktops or application windows using any standard VNC server. It supports multi-user concurrent interaction on the public shared display as well as input redirection so users can control each other's applications. La-come supports separate types of interaction through a Lacome client for window management tasks on the shared display(move, resize, iconify, de-iconify) and for application interactions through the VNC servers. The system architecture provides for Publishers that share information and Navigators that access information. A Lacome client can have either or both, and can initiate additional Publishers on other VNC servers that may not be Lacome clients. Explicit access control policies on both the server side the client side provide a flexible framework for sharing. The architecture builds on standard cross-platform components such as VNC and JRE. Interaction techniques used in the window manager ensure simple and transparent multi-user interactions for managing the shared display space. We illustrate the design and implementation of Lacome and provide insights from initial user experience with the system.

Lacome is a multi-user cross-platform system that supports collaboration in a shared large screen display environment. Lacome allows users to share their desktops or application windows using any standard VNC server. It supports multi-user concurrent interaction on the public shared display as well as input redirection so users can control each other's applications. La-come supports separate types of interaction through a Lacome client for window management tasks on the shared display(move, resize, iconify, de-iconify) and for application interactions through the VNC servers. The system architecture provides for Publishers that share information and Navigators that access information. A Lacome client can have either or both, and can initiate additional Publishers on other VNC servers that may not be Lacome clients. Explicit access control policies on both the server side the client side provide a flexible framework for sharing. The architecture builds on standard cross-platform components such as VNC and JRE. Interaction techniques used in the window manager ensure simple and transparent multi-user interactions for managing the shared display space. We illustrate the design and implementation of Lacome and provide insights from initial user experience with the system. / Science, Faculty of / Computer Science, Department of / Graduate

With the ever increasing amount of digital information, information workers desire more screen real estate to process their daily desktop work. Thanks to the quick advance in display technology, big screens are increasingly affordable and have been gradually adopted in desktop computing environments. A large wall-size high resolution display, a recent emerging class of display which possesses a huge visualization surface, could potentially benefit information processing work. In this dissertation we investigate such a large display as the primary working space for information processing work. We firstly conducted a longitudinal diary study and three control experiments investigating effects of a large display on information processing work. The longitudinal diary study investigates large display use in a personal desktop computing context by comparing it with single- and dual-monitor. The three controlled experiments further investigate the effects of two factors determining resolution of a display—physical size and pixel-density on users’ performance and behaviors. The diary study reveals the distinct behavior patterns of large display users in partitioning screen space and managing windows, while the control experiments deeply reveal the effects of the physical size and pixel density of a display on different information processing tasks. Aside from studying a continuous large display, we also articulate how interior bezels within a tiled-monitor large display affect users’ performance and behaviors in basic visual search and action tasks via a series of controlled experiments. Based on the understanding of large display effects and users’ behavior patterns, we then design new interaction techniques to address a big challenge of working on a large display: managing overflowing windows. We design and implement a large display oriented window management system prototype: WallTop. It includes a set of interaction techniques that provide greater flexibility for managing windows. Usability tests show that users can quickly and easily learn the new techniques and apply them to realistic window management tasks with increased efficiency on a large display.

With the ever increasing amount of digital information, information workers desire more screen real estate to process their daily desktop work. Thanks to the quick advance in display technology, big screens are increasingly affordable and have been gradually adopted in desktop computing environments. A large wall-size high resolution display, a recent emerging class of display which possesses a huge visualization surface, could potentially benefit information processing work. In this dissertation we investigate such a large display as the primary working space for information processing work. We firstly conducted a longitudinal diary study and three control experiments investigating effects of a large display on information processing work. The longitudinal diary study investigates large display use in a personal desktop computing context by comparing it with single- and dual-monitor. The three controlled experiments further investigate the effects of two factors determining resolution of a display—physical size and pixel-density on users’ performance and behaviors. The diary study reveals the distinct behavior patterns of large display users in partitioning screen space and managing windows, while the control experiments deeply reveal the effects of the physical size and pixel density of a display on different information processing tasks. Aside from studying a continuous large display, we also articulate how interior bezels within a tiled-monitor large display affect users’ performance and behaviors in basic visual search and action tasks via a series of controlled experiments. Based on the understanding of large display effects and users’ behavior patterns, we then design new interaction techniques to address a big challenge of working on a large display: managing overflowing windows. We design and implement a large display oriented window management system prototype: WallTop. It includes a set of interaction techniques that provide greater flexibility for managing windows. Usability tests show that users can quickly and easily learn the new techniques and apply them to realistic window management tasks with increased efficiency on a large display.

Large, high resolution displays combine high pixel density with ample physical dimensions. Combination of these two factors creates a multi-scale workspace where object targeting requires both high speed and high accuracy for nearby and far apart targeting. Modern operating systems support dynamic control-display gain adjustment (i.e. cursor acceleration) that helps to maintain both speed and accuracy. However, very large high resolution displays require broad range of control-display gain ratios. Current interaction techniques attempt to solve the problem by utilizing multiple modes of interaction, where different modes provide different levels of pointer precision. We are investigating the question of the value of allowing users to dynamically choose granularity levels for continuous pointing within single mode of interaction via multiple acceleration curves. Our solution offers different cursor acceleration curves depending on the targeting conditions, thus broadening the range of control-display ratios. Our approach utilizes a consumer multitouch touchpad that allows fast and accurate detection of multiple fingers. A user can choose three different acceleration curves based on how many fingers are used for cursor positioning. Our goal is to investigate the effects of such multi-scale interaction and to compare it against standard single curve interaction. / Master of Science

<p> This research presents a new technique for user interface prototyping, called mixed-fidelity prototyping. Mixed-fidelity prototyping combines low-, medium-, and high-fidelity interface elements within a single prototype in a lightweight manner, supporting independent refinement of individual elements. The approach allows designers to investigate alternate designs, including more innovative designs, and elicit feedback from stakeholders without having to commit too early in the process. As well, the approach encourages collaboration among a diverse group of stakeholders throughout the design process. For example, individuals who specialize in specific fidelities, such as high-fidelity components, are able to become involved earlier on in the process. </p> <p> We developed a conceptual model called the Region Model and implemented a proof-of-concept system called ProtoMixer. We demonstrated the mixed-fidelity approach by using ProtoMixer to design an example application. </p> <p> ProtoMixer has several benefits over other existing prototyping tools. With ProtoMixer, prototypes can be composed of multiple fidelities, and elements are easily refined and transitioned between different fidelities. Individual elements can be tied into data and functionality, and can be executed inside prototypes. As well, traditional informal practices such as sketching and storyboarding are supported. Furthermore, ProtoMixer is designed for collaborative use on a high-resolution, large display workspace. </p>

<p> This research presents a new technique for user interface prototyping, called mixed-fidelity prototyping. Mixed-fidelity prototyping combines low-, medium-, and high-fidelity interface elements within a single prototype in a lightweight manner, supporting independent refinement of individual elements. The approach allows designers to investigate alternate designs, including more innovative designs, and elicit feedback from stakeholders without having to commit too early in the process. As well, the approach encourages collaboration among a diverse group of stakeholders throughout the design process. For example, individuals who specialize in specific fidelities, such as high-fidelity components, are able to become involved earlier on in the process. </p> <p> We developed a conceptual model called the Region Model and implemented a proof-of-concept system called ProtoMixer. We demonstrated the mixed-fidelity approach by using ProtoMixer to design an example application. </p> <p> ProtoMixer has several benefits over other existing prototyping tools. With ProtoMixer, prototypes can be composed of multiple fidelities, and elements are easily refined and transitioned between different fidelities. Individual elements can be tied into data and functionality, and can be executed inside prototypes. As well, traditional informal practices such as sketching and storyboarding are supported. Furthermore, ProtoMixer is designed for collaborative use on a high-resolution, large display workspace. </p>

Though many researchers have suggested that 3D virtual environments (VEs) could provide advantages for conceptual learning, few studies have attempted to evaluate the validity of this claim. While many educational VEs share the challenge of providing learners with information within 3D spaces, few researchers have investigated what approaches are used to help learn new information from 3D spatial representations. It is not understood how well learners can take advantage of 3D layouts to help understand information. Additionally, although complex arrangements of information within 3D space can potentially allow for large amounts of information to be presented within a VE, accessing this information can become more difficult due to the increased navigational challenges. Complicating these issues are details regarding display types and interaction devices used for educational applications. Compared to desktop displays, more immersive VE systems often provide display features (e.g., stereoscopy, increased field of view) that support improved perception and understanding of spatial information. Additionally, immersive VE often allow more familiar, natural interaction methods (e.g., physical walking or rotation of the head and body) to control viewing within the virtual space. It is unknown how these features interact with the types of spatial information presentations to affect learning. The research presented in this dissertation investigates these issues in order to further the knowledge of how to design VEs to support learning. The research includes six studies (five empirical experiments and one case study) designed to investigate how spatial information presentations affect learning effectiveness and learner strategies. This investigation includes consideration for the complexity of spatial information layouts, the features of display systems that could affect the effectiveness of spatial strategies, and the degree of navigational control for accessing information. Based on the results of these studies, we created a set of design guidelines for developing VEs for learning-related activities. By considering factors of virtual information presentation, as well as those based on the display-systems, our guidelines support design decisions for both the software and hardware required for creating effective educational Ves. / Ph. D.

Large display environments (LDEs) are interactive physical workspaces featuring one or more static large displays as well as rich interaction capabilities, and are meant to visualize and manipulate very large datasets. Research about mid-air interactions in such environments has emerged over the past decade, and a number of interaction techniques are now available for most elementary tasks such as pointing, navigating and command selection. However these techniques are often designed and evaluated separately on specific platforms and for specific use-cases or operationalizations, which makes it hard to choose, compare and combine them.In this dissertation I propose a framework and a set of guidelines for analyzing and combining the input and output channels available in LDEs. I analyze the characteristics of LDEs in terms of (1) visual output and how it affects usability and collaboration and (2) input channels and how to combine them in rich sets of mid-air interaction techniques. These analyses lead to four design requirements intended to ensure that a set of interaction techniques can be used (i) at a distance, (ii) together with other interaction techniques and (iii) when collaborating with other users. In accordance with these requirements, I designed and evaluated a set of mid-air interaction techniques for panning and zooming, for invoking commands while pointing and for performing difficult pointing tasks with limited input requirements. For the latter I also developed two methods, one for calibrating high-precision techniques with two levels of precision and one for tuning velocity-based transfer functions. Finally, I introduce two higher-level design considerations for combining interaction techniques in input-constrained environments. Designers should take into account (1) the trade-off between minimizing limb usage and performing actions in parallel that affects overall performance, and (2) the decision and adaptation costs incurred by changing the resolution function of a pointing technique during a pointing task.