The COVID-19 virus disrupted all aspects of our daily lives, and though the world is finally returning to normalcy, the pandemic has shown us how ill-prepared we are to support social interactions when expected to remain socially distant. Family members missed major life events of their loved ones; face-to-face interactions were replaced with video chat; and the technologies used to facilitate interim social interactions caused an increase in depression, stress, and burn-out. It is clear that we need better solutions to address these issues, and one avenue showing promise is that of Interpersonal Telepresence. Interpersonal Telepresence is an interaction paradigm in which two people can share mobile experiences and feel as if they are together, even though geographically distributed. In this dissertation, we posit that this paradigm has significant value in one-to-one, asymmetrical contexts, where one user can live-stream their experiences to another who remains at home. We discuss a review of the recent Interpersonal Telepresence literature, highlighting research trends and opportunities that require further examination. Specifically, we show how current telepresence prototypes do not meet the social needs of the streamer, who often feels socially awkward when using obtrusive devices. To combat this negative finding, we present a qualitative co-design study in which end users worked together to design their ideal telepresence systems, overcoming value tensions that naturally arise between Viewer and Streamer. Expectedly, virtual reality techniques are desired to provide immersive views of the remote location; however, our participants noted that the devices to facilitate this interaction need to be hidden from the public eye. This suggests that 360$^\circ$ cameras should be used, but the lenses need to be embedded in wearable systems, which might affect the viewing experience. We thus present two quantitative studies in which we examine the effects of camera placement and height on the viewing experience, in an effort to understand how we can better design telepresence systems. We found that camera height is not a significant factor, meaning wearable cameras do not need to be positioned at the natural eye-level of the viewer; the streamer is able to place them according to their own needs. Lastly, we present a qualitative study in which we deploy a custom interpersonal telepresence prototype on the co-design findings. Our participants preferred our prototype instead of simple video chat, even though it caused a somewhat increased sense of self-consciousness. Our participants indicated that they have their own preferences, even with simple design decisions such as style of hat, and we as a community need to consider ways to allow customization within our devices. Overall, our work contributes new knowledge to the telepresence field and helps system designers focus on the features that truly matter to users, in an effort to let people have richer experiences and virtually bridge the distance to their loved ones.

As time goes on, the demand for higher resolution and more visually rich images only increases. Unfortunately, creating these more realistic computer graphics is pushing our computational resources to their limits. In realistic rendering, one of the common ways 3D objects are represented is as volumetric elements called voxels. Traditionally, voxel data structures are known for their high memory requirements. One of the standard ways these requirements are minimized is by storing the voxels in a sparse voxel octree (SVO). Very recently, a method called High Resolution Sparse Voxel DAGs was presented that can store binary voxel data orders of magnitudes more efficiently than SVOs. This memory efficiency is achieved by converting the tree into a directed acyclic graph (DAG). The method was also shown to have competitive rendering performance to recent GPU ray tracers. Unfortunately, it does not support storing collections of rendering attributes, commonly called materials. These represent a given object's reflectance properties, and are necessary for calculating its perceived color. We present a method for connecting material information to High Resolution Sparse Voxel DAGs for mid-level scenes, with multiple meshes, and several different materials. This is achieved using an extended Sparse Voxel DAG, called a Moxel DAG, and an external data structure for holding the material information, we call a Moxel Table. Our method is much more memory efficient than traditional SVOs, and only increases in efficiency in comparison when at higher resolutions. Because it stores the equivalent information as SVOs, it achieves the exact same visual quality at the same resolutions.

We live in an age when consumers can now shop and browse the web using hand-held devices. This means that competitive companies need to have a website to represent their brand and to conduct business. E-commerce sites need to pay special attention to the usability of their sites, since it has such an impact on how potential costumers view their brand. Jakob Nielsen defines usability as a "quality attribute that assesses how easy user interfaces are to use"; he separates usability into five quality components: learnability, efficiency, memorability, errors and satisfaction. The current standard for testing usability involves having a number of users physically use a site in order to determine where they have trouble. This kind of usability testing can be time consuming and costly. In order to mitigate some of these costs, many tools are being developed to help automate the process. However, many automated tools evaluate only one of the five components, or simply look for errors. In an attempt to increase the reliability and scope of such testing, this paper investigates the effectiveness of automated usability evaluators and proposes methods for future researchers to test them. Specifically, this paper details an experiment performed to test the some freely available usability evaluators against more traditional usability evaluations. The experiment attempts to determine whether automatic usability evaluations might be used as a cheaper alternative to more traditional usability evaluations.

The following paper discusses the application of two subdivision algorithms for the purpose of finding an optimal way of rendering smooth spherical surfaces. Subdivision algorithms are used on three dimensional models. These algorithms typically manipulate the original object to produce one that is more visually pleasing and more realistic to the object we are attempting to recreate. We applied two popular subdivision algorithms to some simple meshes to compare their outcomes. In this project we implemented some of these algorithms in order to gain some insight into how these algorithms differ in the way that they are transforming the input mesh. Our desired goal was to see if there is any basis for which we can say that one algorithm outperforms the other. Our comparison runs through several iterations of subdivision and compares their theses meshes visually. In comparing these meshes our desired visual outcome is a mesh that is more smooth or more spherical. Another metric we looked at was the number of faces being produced for each mesh. In addition, we compared the algorithms in terms of the time they took to perform subdivision. These metrics form the basis for our comparison of performance and we discuss the details of these further in this paper.In our results we found that the two algorithms we are comparing perform quite similarly on certain meshes with respect to the visual output and the time they take to perform subdivision. On meshes of different types however the algorithms might output visually distinguishable meshes upon repeated subdivisions. Finding what factors influence whether the algorithms perform similarly provides an avenue for future work.

This project presents the concepts of modeling cloth objects with different materials by using parameters such as mass, stiffness, and damping. This project also introduces deformation and simulation methods to present the movement and interaction of cloth objects. The implementation is developed using C++ for fast processing but the visualization is done by Maya, which is a professional 3D modeling and animation tool.

New, often free, spatial information applications such as mapping tools, topological imaging, and geographic information systems are becoming increasingly available to the average computer user. These systems, which were once available only to government, scholastic, and corporate institutions with highly skilled operators, are driving a need for new and innovative ways for the average user to navigate and control spatial information intuitively, accurately, and efficiently. Gestures provide a method of control that is well suited to navigating the large datasets often associated with spatial information applications. Several different types of gestures and different applications that navigate spatial data are examined. This leads to the introduction of a system that uses a visual head tracking scheme for controlling of the most common navigation action in the most common type of spatial information application, panning a 2-D map. The proposed head tracking scheme uses head pointing to control the direction of panning. The head tracking control is evaluated against the traditional control methods of the mouse and touchpad, showing a significant performance increase over the touchpad and comparable performance to the mouse, despite limited practice with head tracking.

abstract: Achievement of many long-term goals requires sustained practice over long durations. Examples include goals related to areas of high personal and societal benefit, such as physical fitness, which requires a practice of frequent exercise; self-education, which requires a practice of frequent study; or personal productivity, which requires a practice of performing work. Maintaining these practices can be difficult, because even though obvious benefits come with achieving these goals, an individual's willpower may not always be sufficient to sustain the required effort. This dissertation advocates addressing this problem by designing novel interfaces that provide people with new practices that are fun and enjoyable, thereby reducing the need for users to draw upon willpower when pursuing these long-term goals. To draw volitional usage, these practice-oriented interfaces can integrate key characteristics of existing activities, such as music-making and other hobbies, that are already known to draw voluntary participation over long durations. This dissertation makes several key contributions to provide designers with the necessary tools to create practice-oriented interfaces. First, it consolidates and synthesizes key ideas from fields such as activity theory, self-determination theory, HCI design, and serious leisure. It also provides a new conceptual framework consisting of heuristics for designing systems that draw new users, plus heuristics for making systems that will continue drawing usage from existing users over time. These heuristics serve as a collection of useful ideas to consider when analyzing or designing systems, and this dissertation postulates that if designers build these characteristics into their products, the resulting systems will draw more volitional usage. To demonstrate the framework's usefulness as an analytical tool, it is applied as a set of analytical lenses upon three previously-existing experiential media systems. To demonstrate its usefulness as a design tool, the framework is used as a guide in the development of an experiential media system called pdMusic. This system is installed at public events for user studies, and the study results provide qualitative support for many framework heuristics. Lastly, this dissertation makes recommendations to scholars and designers on potential future ways to examine the topic of volitional usage. / Dissertation/Thesis / Ph.D. Media Arts and Sciences 2013

This thesis introduces a novel Eulerian-on-Lagrangian (EoL) approach for simulating cloth. This approach allows for the simulation of traditionally difficult cloth scenarios, such as draping and sliding cloth over sharp features like the edge of a table. A traditional Lagrangian approach models a cloth as a series of connected nodes. These nodes are free to move in 3d space, but have difficulty with sliding over hard edges. The cloth cannot always bend smoothly around these edges, as motion can only occur at existing nodes. An EoL approach adds additional flexibility to a Lagrangian approach by constructing special Eulerian on Lagrangian nodes (EoL Nodes), where cloth material can pass through a fixed point. On contact with the edge of a box, EoL nodes are introduced directly on the edge. These nodes allow the cloth to bend exactly at the edge, and pass smoothly over the area while sliding. Using this ‘Eulerian-on-Lagrangian’ discretization, a set of rules for introducing and constraining EoL Nodes, and an adaptive remesher, This simulator allows cloth to move in a sliding motion over sharp edges. The current implementation is limited to cloth collision with static boxes, but the method presented can be expanded to include contact with more complicated meshes and dynamic rigid bodies.

With the emergence of big data, scientific data analysis and visualization (DAV) tools are critical components of the data science software ecosystem; the usability of these tools is becoming extremely important to facilitate next-generation scientific discoveries. JupyterLab has been considered as one of the best polyglot, web-based, open-source data science tools. As the next phase of extensible interface for the classic iPython Notebooks, this tool supports interactive data science and scientific computing across multiple programming languages with great performances. Despite these advantages, previous heuristics evaluation studies have shown that JupyterLab has some significant flaws in the data visualization side. The current DAV system in JupyterLab heavily relies on users’ understanding and familiarity with certain visualization libraries, and doesn’t support the golden visual-information-seeking mantra of “overview first, zoom and filter, then details-on-demand”. These limitations often lead to a workflow bottleneck at the start of a project. In this thesis, we present ‘JupyterLab_Voyager’, an extension for JupyterLab that provides a graphical user interface (GUI) for data visualization operations and couples faceted browsing with visualization recommendation to support exploration of multivariate, tabular data, as a solution to improve the usability of the DAV system. The new plugin works with various types of datasets in the JupyterLab ecosystem; using the plugin you can perform a high-level graphical analysis of fields within your dataset sans coding without leaving the JupyterLab environment. It helps analysts learn about the dataset and engage in both open-ended exploration and target specific answers from the dataset. User testings and evaluations demonstrated that this implementation has good usability and significantly improves the DAV system in JupyterLab.

With the advent of modern graphics and computing hardware and cheaper sensor and display technologies, virtual reality is becoming increasingly popular in the fields of gaming, therapy, training and visualization. Earlier attempts at popularizing VR technology were plagued by issues of cost, portability and marketability to the general public. Modern screen technologies make it possible to produce cheap, light head-mounted displays (HMDs) like the Oculus Rift, and modern GPUs make it possible to create and deliver a seamless real-time 3D experience to the user. 3D sensing has found an application in virtual and augmented reality as well, allowing for a higher level of interaction between the real and the simulated. There are still issues that persist, however. Many modern graphics/game engines still do not provide developers with an intuitive or adaptable interface to incorporate these new technologies. Those that do, tend to think of VR as a novelty afterthought, and even then only provide tailor-made extensions for specific hardware. The goal of this paper is to design and implement a functional, general-purpose VR engine using abstract interfaces for much of the hardware components involved to allow for easy extensibility for the developer.