Donald F. Caldwell

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The routers in an Autonomous System (AS) must distribute the information they learn about how to reach external destinations. Unfortunately, today's internal Border Gateway Protocol (iBGP) architectures have serious problems: a "full mesh" iBGP configuration does not scale to large networks and "route reflection" can introduce problems such as protocol(More)
Human error in configuring routers undermines attempts to provide reliable, predictable end-to-end performance on IP networks. Manual configuration, while expensive and error-prone, is the dominant mode of operation, especially for large enterprise networks. These networks often lack the basic building blocks---an accurate equipment inventory, a debugged(More)
We study the problem of compressing massive tables. We devise a novel compression paradigm—training for lossless compression— which assumes that the data exhibit dependencies that can be learned by examining a small amount of training material. We develop an experimental methodology to test the approach. Our result is a system, pzip, which outperforms gzip(More)
Relations between sleep and memory were examined as a function of aging in rats. Sleep (24 hr), passive avoidance retention, and choline acetyltransferase (CAT) activity were assessed in 3 age-groups (6, 15, and 24 months old). Age-related alterations were evident in sleep, memory, and cortical and striatal CAT activity. Retention deficits in old rats were(More)
Administration of a single non-convulsive dose of insulin (1.0, I.U./kg., I.P.) which produced no observable gross behavioral changes in rats, reduced rapid eye movement (REM) sleep time 100% in the first 3 hrs. and 82% by the 4th hr., reaching control subject levels (saline-treated) by the 6th hr. In contrast, slow-wave sleep (NREM) time in insulin treated(More)
Administration of a high dose of glucose (2.5 g/kg, i.p.) that is known to produce severe hyperglycemia in euglycemic rats suppressed rapid eye movement (REM) sleep time significantly during the first three hours of 8 hr total electroencephalogram (EEG) recording period. Co-administration of glucose (2.5 g/kg, i.p.) and a non-convulsive dose of insulin (1.0(More)
Thh design of a plug-holder unit for electrode implants is described. The plug-holder attaches to the stereotaxic and facilitates the insertion of the electrode contact pins into the plug by retaining the connector plug in a fixed rigid position. In addition, it prevents the accidental breakage of contact lead wires which can normally occur during the(More)
The sleep-wake cycle of 12 tryptophan dietary deficient rats and their non-deficient paired controls were observed for a 8:00 a.m. to 8:00 p.m. period. EEG, EMG and body activity were continuously monitored on polygraphic recordings throughout the 12 hr observation period. The results indicate no significant difference between the tryptophan deficient and(More)