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 bu(G) and determine the exact value(More)
Much of the literature on ceteris paribus laws is based on a misguided egalitarianism about the sciences. For example, it is commonly held that the special sciences are riddled with ceteris paribus laws; from this many commentators conclude that if the special sciences are not to be accorded a second class status, it must be ceteris paribus all the way down(More)
The health risks to babies from pollutants in house dust may be 100 times greater than for adults. The young ingest more dust and are up to ten times more vulnerable to such exposures. House dust is the main exposure source for infants to allergens, lead, and PBDEs, as well as a major source of exposure to pesticides, PAHs, Gram-negative bacteria, arsenic,(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)
The motion imagery community will 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. We conducted a series of user evaluations to understand and quantify the(More)