A. B. Stephens

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PURPOSE This preliminary study attempted to identify the frequency of orthostatic hypotension (OH) in community dwelling older adults who volunteered to participate in an 8-week, heavy-resistance, strength-training program. It also assessed the effect of the strength-training program on OH. METHODS From a larger study (n = 53) on high-resistance strength(More)
We consider a distributed database with partial replication of data objects located on a ring network. Certain placements of replicated objects are shown to optimize the probability of read-only success and the probability of writeonly success. We also obtain optimal placements for k-terminal reliability and expected minimal path length for read-only and(More)
This paper presents results of preliminary work concerning the analytical modeling of a robotic tape library using stochastic automata. This model is a rst approximation which we use to test the eeciency and accuracy of stochastic automata networks as a modeling tool. The eeects of interactive get and put requests, migration, and purging at online and(More)
Past performance analyses of resource sharing systems have often assumed uniform resource access distributions. This assumption is made for reasons of computational tractability. In some of these analyses it has been conjectured that such an assumption is optimistic, in the sense that it minimizes the probability of resource conflict. In this paper we give(More)
Utilizing a combination of above-canopy and intracanopy lighting may prove highly beneficial in a Lunar Controlled Ecological Life Support System (LCELSS) as a means of increasing volumetric efficiency of plant growth. Intracanopy lighting was not found to be detrimental to plant tissue and production per plant when cowpeas were grown using sand culture.(More)