David B Yan

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–A number of successful applications of automated planning and scheduling applications to spacecraft operations have recently been reported in the literature. However, these applications have been one-of-a-kind applications that required a substantial amount of development effort. In this paper, we describe ASPEN, a modular, reconfigurable application(More)
Thermoelectric modules are an important alternative to heat engines in the harvesting of waste heat. Electrical-thermal analogs are often employed when studying heat conduction and this approach can be extended to develop a model for thermoelectric effects. In this article, the coupled thermoelectric partial differential equations are discretized using the(More)
The purpose of this study was to determine the mechanical response of the lamina cribrosa (LC) to elevated intraocular pressure (IOP) so as to identify possible mechanisms of optic nerve damage in early glaucoma. Ten pairs of normal human eyes were fixed after 24 hours' exposure to 50 mm Hg pressure (experimental eyes) or 5 mm Hg pressure (contralateral(More)
— This paper describes the application of an automated planning and scheduling system to the NASA Earth Orbiting 1 (EO-1) mission. The planning system, ASPEN, is used to autonomously schedule the daily activities of the satellite. The satellite and operations constraints are encoded within a software model used by the planner. This paper includes a(More)
Previous studies show that hydrogen peroxide (H2O2) is present in the aqueous humor of many species and is capable of affecting outflow facility in animal model experiments. To study the hypothesis that oxidative damage to the outflow pathway may play a role in the pathogenesis of primary open-angle glaucoma, 3 mM H2O2 with 20 mM 3-aminotriazole and 1 mM(More)
A number of successful applications of automated planning and scheduling applications to spacecraft operations have recently been reported in the literature. However, these applications have been one-of-a-kind applications that required a substantial amount of development effort. In this paper, we describe ASPEN (Automated Planning/Scheduling Environment),(More)
PURPOSE Previous studies have suggested that IOP-induced deformation of the optic nerve head (ONH) at the level of the lamina cribrosa may contribute to axonal damage in glaucomatous optic neuropathy. Our purpose was to introduce a novel enucleated eye model for characterizing acute IOP-induced changes in ONH topography, and to develop improved analytical(More)
—The Deep Space One (DS1) mission, scheduled to fly in 1998, will be the first spacecraft to feature an on-board planner. The planner is part of an artificial intelligence based control architecture that comprises a planner/scheduler, a plan execution engine, and a model-based fault diagnosis and reconfiguration engine. This autonomy architecture reduces(More)
—The Deep Space One (DS1) mission, scheduled to fly in 1998, will be the first NASA spacecraft to feature an on-board planner. The planner is part of an artificial intelligence based control architecture that comprises the planner/scheduler, a plan execution engine, and a model-based fault diagnosis and reconfiguration engine. This autonomy architecture(More)
BACKGROUND This study was designed to evaluate the occurrence and severity of ocular hyperemia in subjects with elevated intraocular pressure (IOP) due to primary open angle glaucoma (POAG) or ocular hypertension (OHT) following treatment with bimatoprost 0.01% in a real-world clinical setting. METHODS This was an open-label, observational study conducted(More)