Framework for a space shuttle main engine health monitoring system

A framework developed for a health management system (HMS) which is directed at improving the safety of operation of the Space Shuttle Main Engine (SSME) is summarized. An emphasis was placed on near term technology through requirements to use existing SSME instrumentation and to demonstrate the HMS during SSME ground tests within five years. The HMS framework was developed through an analysis of SSME failure modes, fault detection algorithms, sensor technologies, and hardware architectures. A key feature of the HMS framework design is that a clear path from the ground test system to a flight HMS was maintained. Fault detection techniques based on time series, nonlinear regression, and clustering algorithms were developed and demonstrated on data from SSME ground test failures. The fault detection algorithms exhibited 100 percent detection of faults, had an extremely low false alarm rate, and were robust to sensor loss. These algorithms were incorporated into a hierarchical decision making strategy for overall assessment of SSME health. A preliminary design for a hardware architecture capable of supporting real time operation of the HMS functions was developed. Utilizing modular, commercial off-the-shelf components produced a reliable low cost design with the flexibility to incorporate advances in algorithm and sensor technology as they become available

Effect of food on bioavailability of chloroquine

The bioavailability of chloroquine in 7 healthy adult male volunteers was assessed with and without a standard breakfast. Chloroquine (600 mg base) was administered orally and timed blood samples were obtained for determination of plasma concentrations. The results suggest that the AUC and peak plasma levels were significantly higher when chloroquine was administered together with food, although the rate of absorption was not different. It appears, therefore, that food facilitates chloroquine absorption and the extent of absorption is significantly modified. Hence administration of chloroquine together with food appears to be an advisable clinical practice

Indocyanine green clearance in the undernourished adults

1. Indocyanine green clearance was studied in eight undernourished subjects. 2. The data showed that in mild to moderately, undernourished adult males, the plasma concentration of ICG were low, the t 0.5 tended to prolong, as a result of increased volume of distribution. 3. However, the ICG clearance was not found to be affected indicating that the clearance of drugs with a high hepatic extraction ratio is unlikely to be altered in these subjects

Chloroquine kinetics in the undernourished

The plasma and whole blood kinetics of chloroquine was studied in 7 normal and 8 undernourished subjects following a single oral dose of 600 mg. The terminal half-lives were similar in both groups. The AUC was also similar in the 2 groups, even though a higher dose per kg body weight was administered to the undernourished. This was probably because of faster clearance in this group. Chloroquine uptake by erythrocytes, its main site of action in malaria, was also comparable in the two groups. The plasma concentration of chloroquine over a period of time was found to be similar in 4 normal and 4 undernourished subjects following administration of 1.5 g of the drug in divided doses. The undernourished appear, therefore, to handle chloroquine in such a way that they do not suffer a greater risk of toxicity than normals