Thesis Proposal Presentation by Curt Holmer on October 18th
Space Studies master’s student, Curt Holmer, will give his thesis proposal presentation as follows.
When: Friday, October 18th at 11:15 AM
Where: Ryan Hall, Room 111
Title: 'Bio-Regenerative Life Support Systems Functional Stability and Limitations, a Theoretical Modeling Approach’
Experiments such as Russia’s BIOS series, NASA’s BioPLEX, ESA’s MELiSSA, and Japan’s CEEF have shown that micro algae and higher plants combined with physical-chemical material converters can be a successful part of a Biological Life Support System or a Closed Ecological Life Support System. Fish have long been pared with agriculture throughout much of human history and provide many benefits beyond the addition of protein to a grain farmer’s diet. These benefits while they have been understood by local farmers for millennia have only recently been (attempted for systematic scientific study) scientifically and systematically studied. Organizations concerned with optimizing crop yields under sustainable conditions such as the Food and Agriculture Department at the United Nations and the World Food Organization have examined and published best practices for the integration of fish with agriculture. This is not to say that integration of fish with a bio-reactor life support system is a simple as adding fish to a rice paddy, however there are distinct benefits along with challenges as was seen with ESA’s Closed Equilibrated Biological Aquatic System (C.E.B.A.S). Small scale, direct dependence closed loop systems have been proven for both short and long periods of time as we have seen with BioPLEX, MELiSSA, and CEBAS experiments and the commercial Ecosphere products. When the dependencies and factors are known and understood, as with CEBAS and Ecospheres, creating a stable environment with known measuring points can be easily accomplished.
However as the larger experiments have shown, more complex environments are attempted, stability issues arise giving way to critical transitions, which are sudden and often irreversible, leading the collapse of the system. Given the time and scale required to test these dependencies and conditions, knowing the precursors of an impending transition or being able to predict critical transitions in these systems is highly desirable. Generalized models can achieve this and may even reduce the amount of time series data required to validate the stability of a given system. Drawing on recent research from the biological, environmental, and systems fields, a generalized framework model can be constructed to generate early warnings of critical transitions.
Additionally, one of the larger issues that have been identified with bio-reactors that utilize micro-algae is the biomass that is produced. While some of this biomass can be utilized as, among other things, a food supplement to the crew, much of the bio-mass produced is rendered as in-editable and must be broken down by other methods such as physical-chemical converters bringing another technical instabilities into the entire system. Many of the species considered for use in bio reactors can also be utilized as a primary food source for fish with minimal processing. With the addition of some higher aquatic plants, a sustainable closed loop system can be created. Many types of micro-algae can be utilized in BLSS bio-reactors, along with higher aquatic plants and fish and invertebrate species that are commonly used in mixed aquaculture/agriculture and will be examined as a possible member(s). This research project will examine modeling of BLSS systems with different species while examining sustainability, yields and scalability of the different mixes.
Note: Thesis proposal presentations are not webcast live unless an off-campus thesis committee member requires it. However, all thesis defenses are broadcast live and available for later viewing at this site.