Monitoring and control technologies for bioregenerative life support systems/CELSS

The development of a controlled Ecological Life Support System (CELSS) will require NASA to develop innovative monitoring and control technologies to operate the different components of the system. Primary effort over the past three to four years has been directed toward the development of technologies to operate a biomass production module. Computer hardware and software required to operate, collect, and summarize environmental data for a large plant growth chamber facility were developed and refined. Sensors and controls required to collect information on such physical parameters as relative humidity, temperature, irradiance, pressure, and gases in the atmosphere; and PH, dissolved oxygen, fluid flow rates, and electrical conductivity in the nutrient solutions are being developed and tested. Technologies required to produce high artificial irradiance for plant growth and those required to collect and transport natural light into a plant growth chamber are also being evaluated. Significant effort was directed towards the development and testing of a membrane nutrient delivery system required to manipulate, seed, and harvest crops, and to determine plant health prior to stress impacting plant productivity are also being researched. Tissue culture technologies are being developed for use in management and propagation of crop plants. Though previous efforts have focussed on development of technologies required to operate a biomass production module for a CELSS, current efforts are expanding to include technologies required to operate modules such as food preparation, biomass processing, and resource (waste) recovery which are integral parts of the CELSS

Atmospheric leakage and condensate production in NASA's biomass production chamber. Effect of diurnal temperature cycles

A series of tests were conducted to monitor atmospheric leakage rate and condensate production in NASA's Biomass Production Chamber (BPC). Water was circulated through the 64 plant culture trays inside the chamber during the tests but no plants were present. Environmental conditions were set to a 12-hr photoperiod with either a matching 26 C (light)/20 C (dark) thermoperiod, or a constant 23 C temperature. Leakage, as determined by carbon dioxide decay rates, averaged about 9.8 percent for the 26 C/20 C regime and 7.3 percent for the constant 23 C regime. Increasing the temperature from 20 C to 26 C caused a temporary increase in pressure (up to 0.5 kPa) relative to ambient, while decreasing the temperature caused a temporary decrease in pressure of similar magnitude. Little pressure change was observed during transition between 23 C (light) and 23 C (dark). The lack of large pressure events under isothermal conditions may explain the lower leakage rate observed. When only the plant support inserts were placed in the culture trays, condensate production averaged about 37 liters per day. Placing acrylic germination covers over the tops of culture trays reduced condensate production to about 7 liters per day. During both tests, condensate production from the lower air handling system was 60 to 70 percent greater than from the upper system, suggesting imbalances exist in chilled and hot water flows for the two air handling systems. Results indicate that atmospheric leakage rates are sufficiently low to measure CO2 exchange rates by plants and the accumulation of certain volatile contaminants (e.g., ethylene). Control system changes are recommended in order to balance operational differences (e.g., humidity and temperature) between the two halves of the chamber

Electrolytic Removal of Nitrate From CELSS Crop Residues

The controlled ecological life support system (CELSS) resource recovery system is a waste processing system using aerobic and anaerobic bioreactors to recover plant nutrients and secondary foods from inedible biomass. Crop residues contain significant amounts of nitrate which presents two problems: (1) both CELSS biomass production and resource recovery consume large quantities of nitric acid, (2) nitrate causes a variety of problems in both aerobic and anaerobic bioreactors. A technique was proposed to remove the nitrate from potato inedible biomass leachate and to satisfy the nitric acid demand using a four compartment electrolytic cell

Paper Session II-B - Bioregenerative Life Support Systems for Mars Missions

Human space travel to Mars will require traveling further and staying longer in space than ever before. The traditional approach of stowing life support consumables (i.e., food, 0 2, and clean water) will be transport dependent and too costly, and regenerative technologies will be required. One approach would involve the use of bi ore generative life support systems, where plants would produce food, clean water, and 02 while removing C02, and microbial systems would process liquid and solid wastes. These systems might provide a small fraction (e.g., 5-25%) oflife support needs for early missions, but increase as surface outposts expand. Through bioregenerative systems and especially the use of green plants to complement human metabolic products, surface outposts can achieve a high level of autonomy and hence become less dependent on resupply from Earth. Significant increases in power, mass and volume will be required to accommodate these bioregenerative systems. To achieve reliable operations of plant production systems and microbial waste processors, innovative and cost effective methods will be needed to sustain long-term missions to optimize the components of life support systems

A Syntax-Directed Editor for Borland’s Turbo Pascal

This study details the design and implementation of the LSD program, a syntax-directed editor for use in editing the source code for Borland’s Turbo Pascal. LSD is a dual-mode editor which allows both traditional text editing and also grammar-based editing. LSD promotes better programming for novice users by allowing the user to edit the program with a graphical representation of a parse tree. A list of syntactically correct choices is displayed at each point where a choice must be made in the structure of the program. Since only these choices are available, no syntax errors are possible. For more advanced users, the ability to take an existing program and display the syntax tree will help show the underlying structure of the Pascal language grammar

A weak link in the chain: The Joint Chiefs of Staff and the Truman-MacArthur controversy during the Korean War.

This work examines the actions of the Joint Chiefs of Staff during the first year of the Korean War. Officially created in 1947, the Joint Chiefs saw their first true test as an institution during the conflict. At various times, the members of the JCS failed to issue direct orders to their subordinate, resulting in a divide between the wishes of President Truman and General MacArthur over the conduct of the war. By analyzing the interaction between the Joint Chiefs and General Douglas MacArthur, the flaws of both the individual Chiefs as well as the organization as a whole become apparent. The tactical and strategic decisions faced by the JCS are framed within the three main stages of the Korean War

Microinvertebrates in CELSS Hydroponic Rhizosphere: Experimental Invasion as a Test of Community Stability and a Test of a Method to Measure Bacterivory

This report consists of two separate draft manuscripts, each prepared for submittal to a peer-reviewed journal after Kennedy Space Center (KSC) colleague editorial review and final revision. References for the two papers have been combined in this report. The two manuscripts are: (1) Experimental invasion of aquatic rhizosphere habitat and invertebrate communities, and (2) Lysozyme analysis is neither protistan- or bacteriore-specific

Clustered engine study

Several topics are presented in viewgraph form which together encompass the preliminary assessment of nuclear thermal rocket engine clustering. The study objectives, schedule, flow, and groundrules are covered. This is followed by the NASA groundrules mission and our interpretation of the associated operational scenario. The NASA reference vehicle is illustrated, then the four propulsion system options are examined. Each propulsion system's preliminary design, fluid systems, operating characteristics, thrust structure, dimensions, and mass properties are detailed as well as the associated key propulsion system/vehicle interfaces. A brief series of systems analysis is also covered including: thrust vector control requirements, engine out possibilities, propulsion system failure modes, surviving system requirements, and technology requirements. An assessment of vehicle/propulsion system impacts due to the lessons learned are presented

Recognizing and integrating wildlife as Elwha restoration agents

Ecosystem restoration involving large dam removal spans large spatial extents, long time scales, and diverse societal constituencies. Restoration success requires collaboration among partner organizations. Success also can be facilitated by integrating components and processes of the ecosystem itself in restoration planning and practice. We review early and future roles of wildlife in restoration of valleys flooded by Elwha dams, with implications for dam removals on other rivers. Detecting early wildlife responses depended on baseline inventories prior to dam removal, followed by monitoring during and after dam removal. Pre-removal studies revealed patterns of small and mid-sized mammal occupancy, bear movement, amphibian occupancy, and avian distributions and species composition. In the few years since dam removal, wildlife colonization of exposed reservoir beds has been rapid, dominated by early successional and mobile species. Wildlife also perform important restoration functions, and contribute to all nine attributes defining restored ecosystems. This early in Elwha restoration, conspicuous wildlife functions include native seed dispersal to restoration sites, herbivore effects on revegetation, and organic matter dispersal to nutrient-poor sediments. In future decades, diverse wildlife also will help restore terrestrial-aquatic connections by dispersing nutrients from increasing salmon runs to riparian and terrestrial areas. Each of these wildlife roles is influenced by spatial distributions of pre-dam structural legacies and structures placed during active restoration efforts, particularly large woody debris. By placing these structures in locations and configurations that support wildlife functions, restoration planning and practice more effectively integrate wildlife in restoration. Benefits include increasing the rate of restoration progress and directing it along more desirable trajectories. In this way, the collaborative interdisciplinary approach in Elwha restoration can be expanded in future restoration projects to encompass active collaboration with the ecosystem itself