John Roberts

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The bondage number b(G) of a non empty graph G is the minimum number of edger whose removal from G results in a graph having domination number greater than the domination number of G. In this paper we characterize graphs for which b(G) = p − 1 and b(G) = (γ − 1) ˙ +1. We also introduce the concept of uniform bondage number b u (G) and determine the exact(More)
Refreshable Braille provides a critical path to display accessibility. High cost and reliability issues severely limit the market for existing Braille displays. A novel wheel-based design addresses reliability issues, and provides continuous Braille text with many-fold reduction in cost. 1. Introduction The increasingly pervasive influence of information(More)
By analysis of the primary cost factors for existing refreshable Braille displays, a team at NIST has pioneered a new technology that can reduce the cost of the electromechanical portions of a Braille display by an extremely large factor, and the overall cost of a Braille display by as much as a factor of ten. A massive cost reduction in displays creates a(More)
The motion imagery community would benefit from the availability of standard measures for assessing image interpretability. The National Imagery Interpretability Rating Scale (NIIRS) has served as a community standard for still imagery, but no comparable scale exists for motion imagery. Several considerations unique to motion imagery indicate that the(More)