Paper Session II-B - Optical Diagnostics: Reagentless Chemistry for Extended Space Flights

Maintaining the health and safety of the crews of spacecraft remain the highest priorities. Health monitoring requires at least two overlapping activities: (1) frequent or continuous monitoring of bodily functions to determine normalcy or deviation from normalcy, and (2) specific diagnosis and treatment of diseases. Thus, with a broad mandate and limited resources, the spacecraft must provide the diagnostic capabilities for quickly and accurately diagnosing a wide range of diseases. Optical devices, though still in the early developmental stages, diagnose diseases by analyzing and quantitating the spectra of metabolites and other substances non-invasively and without using chemical reagents. Once commercially available, optical devices will replace many clinical tests that use chemical reagents for diagnostics

Paper Session III-B - Measurements of Oxygen in Biological & Medical Experiments

Since the maintenance of the appropriate levels of oxygen is essential for ensuring the success of many of the specialized experiments in space missions, such as tissue culture experiments, the continuous monitoring of partial pressures of oxygen provides important data. We are developing optical methods of monitoring not only oxygen but also many dissolved constituents in blood and tissue culture solutions. The optical system uses tiny optical fibers, which easily fit inside a fine-gauged needle, for monitoring each specimen. Moreover, the beam can be split so that multiple specimens can be monitored simultaneously. The same optical technology can also be used for monitoring the blood chemistry of humans and animals; it is minimally invasive. It has a medical application for measuring tissue partial pressures of oxygen

Partial least-squares: Theoretical issues and engineering applications in signal processing

In this paper we present partial least-squares (PLS), which is a statistical modeling method used extensively in analytical chemistry for quantitatively analyzing spectroscopic data. Comparisons are made between classical least-squares (CLS) and PLS to show how PLS can be used in certain engineering signal processing applications. Moreover, it is shown that in certain situations when there exists a linear relationship between the independent and dependent variables, PLS can yield better predictive performance than CLS when it is not desirable to use all of the empirical data to develop a calibration model used for prediction. Specifically, because PLS is a factor analysis method, optimal selection of the number of PLS factors can result in a calibration model whose predictive performance is considerably better than CLS. That is, factor analysis (rank reduction) allows only those features of the data that are associated with information of interest to be retained for development of the calibration model, and the remaining data associated with noise are discarded. It is shown that PLS can yield physical insight into the system from which empirical data has been collected. Also, when there exists a non-linear cause-and-effect relationship between the independent and dependent variables, the PLS calibration model can yield prediction errors that are much less than those for CLS. Three PLS application examples are given and the results are compared to CLS. In one example, a method is presented using PLS for parametric system identification. Using PLS for system identification allows simultaneous estimation of the system dimension and the system parameter vector associated with a minimal realization of the system

Principles of neurocomputing for science and engineering

xxx, 642 p. : ill. ; 24 cm

Atmospheric controls on ground and space-based remote detection of volcanic ash Injection into the atmosphere, and link to early warning systems for aviation hazard mitigation

Violent volcanic eruptions, common especially in Southeast Asia, posean ongoing serious threat to aviation and local communities. However, the physicalconditions at the eruptive vent are difficult to estimate. In order to tackle thisproblem, satellite imagery and infrasound can rapidly provide information aboutstrong eruptions of volcanoes not closely monitored by on-site instruments. Forexample, the recent infrasonic array at Singapore, installed to support the coverageof the International Monitoring System, allows identification of nearby eruptingvolcanoes based on the characteristics of the recorded signal. But, due to its locationclose to the equator, seasonal changes in the wind velocity structure of the atmospherestrongly affect its potential to detect small volcanic eruptions at certainazimuths. To overcome this limit, infrasound could be augmented with satellite data. Yet, with the high average cloud cover in Southeast Asia, there are alsochallenges to identify weak volcanic plumes using satellite based monitoringtechniques. In this chapter, we aim to examine the relative strengths and weaknessesof the two technologies to better understand the possibility to improveoverall detection capability by combining infrasound with satellite imagery