On the Power of Manifold Samples in Exploring Configuration Spaces and the Dimensionality of Narrow Passages

We extend our study of Motion Planning via Manifold Samples (MMS), a general algorithmic framework that combines geometric methods for the exact and complete analysis of low-dimensional configuration spaces with sampling-based approaches that are appropriate for higher dimensions. The framework explores the configuration space by taking samples that are entire low-dimensional manifolds of the configuration space capturing its connectivity much better than isolated point samples. The contributions of this paper are as follows: (i) We present a recursive application of MMS in a six-dimensional configuration space, enabling the coordination of two polygonal robots translating and rotating amidst polygonal obstacles. In the adduced experiments for the more demanding test cases MMS clearly outperforms PRM, with over 20-fold speedup in a coordination-tight setting. (ii) A probabilistic completeness proof for the most prevalent case, namely MMS with samples that are affine subspaces. (iii) A closer examination of the test cases reveals that MMS has, in comparison to standard sampling-based algorithms, a significant advantage in scenarios containing high-dimensional narrow passages. This provokes a novel characterization of narrow passages which attempts to capture their dimensionality, an attribute that had been (to a large extent) unattended in previous definitions.Comment: 20 page

Human-computer interaction and sociological insight: A theoretical examination and experiment in building affinity in small groups

The juxtaposition of classic sociological theory and the, relatively, young discipline of human-computer interaction (HCI) serves as a powerful mechanism for both exploring the theoretical impacts of technology on human interactions as well as the application of technological systems to moderate interactions. It is the intent of this dissertation to contribute to the knowledge of both HCI and sociology through a brief discussion of the state of sociological theory and its shortcomings, the design and evaluation of a system to promote social affinity in dyadic work, a method for empirically measuring affinity free from the social desirability bias of surveys, and a proposal for a new direction for HCI to include classic sociological theories. Ultimately, this dissertation serves as an introduction to a series of future research projects by laying the theoretical and methodological foundations for exploring indirect technological mediation of social interactions

Design and evaluation of auditory spatial cues for decision making within a game environment for persons with visual impairments

An audio platform game was created and evaluated in order to answer the question of whether or not an audio game could be designed that effectively conveys the spatial information necessary for persons with visual impairments to successfully navigate the game levels and respond to audio cues in time to avoid obstacles. The game used several types of audio cues (sounds and speech) to convey the spatial setup (map) of the game world. Most audio-only players seemed to be able to create a workable mental map from the game\u27s sound cues alone, pointing to potential for the further development of similar audio games for persons with visual impairments. The research also investigated the navigational strategies used by persons with visual impairments and the accuracy of the participants\u27 mental maps as a consequence of their navigational strategy. A comparisons of the maps created by visually impaired participants with those created by sighted participants playing the game with and without graphics, showed no statistically significant difference in map accuracy between groups. However, there was a marked difference between the number of invented objects when we compared this value between the sighted audio-only group and the other groups, which could serve as an area for future research

High‐density lipoprotein‐associated paraoxonase 1: a possible prognostic biomarker for heart failure?

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/137330/1/ejhf817_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137330/2/ejhf817.pd