Refine Your Search

Search Results

Viewing 1 to 6 of 6
Technical Paper

Modeling Stochastic Performance and Random Failure

2007-07-09
2007-01-3027
High costs and extreme risks prevent the life testing of NASA hardware. These unavoidable limitations prevent the determination of sound reliability bounds for NASA hardware; thus the true risk assumed in future missions is unclear. A simulation infrastructure for determining these risks is developed in a configurable format here. Positive preliminary results in preparation for validation testing are reported. A stochastic filter simulates non-deterministic output from the various unit processes. A maintenance and repair module has been implemented with several levels of complexity. Two life testing approaches have been proposed for use in future model validation.
Technical Paper

Testing Heuristic Tools for Life Support System Analysis

2007-07-09
2007-01-3225
BioSim is a simulation tool which captures many basic life support functions in an integrated simulation. Conventional analyses can not efficiently consider all possible life support system configurations. Heuristic approaches are a possible alternative. In an effort to demonstrate efficacy, a validating experiment was designed to compare the configurational optima discovered by heuristic approaches and an analytical approach. Thus far, it is clear that a genetic algorithm finds reasonable optima, although an improved fitness function is required. Further, despite a tight analytical fit to data, optimization produces disparate results which will require further validation.
Technical Paper

Loading Balance and Influent pH in a Solids Thermophilic Aerobic Reactor

2005-07-11
2005-01-2982
The application of biological treatment to solid waste is very promising to facilitate recycling of water, carbon, and nutrients and to reduce the resupply needs of long-term crewed space missions. Degradation of biodegradable solid wastes generated during such a mission is under investigation as part of the NASA Center of Research and Training (NSCORT) at Purdue University. Processing in the solids thermophilic aerobic reactor (STAR) involves the use of high temperature micro-aerobic slurry conditions to degrade solid wastes, enabling the recycling of water, carbon, and nutrients for further downstream uses. Related research presently underway includes technical development and optimization of STAR operations as well as a complementary evaluation of post-STAR processing for gas-stream purification, water recovery by condensate purification, and residuals utilization for both mushroom growth media and nutritional support for fish growth.
Technical Paper

Modeling of a Composting System within BIO-Plex

2001-07-09
2001-01-2323
BIO-Plex is a ground-based test bed currently under development by NASA for testing technologies and practices that may be utilized in future long-term life support missions. All aspects of such an Advanced Life Support (ALS) System must be considered to confidently construct a reliable system, which will not only allow the crew to survive in harsh environments, but allow the crew time to perform meaningful research. Effective handling of solid wastes is a critical aspect of the system, especially when recovery of resources contained in the waste is required. This is particularly important for ALS Systems configurations that include a Biomass Production Chamber. In these cases, significant amounts of inedible biomass waste may be produced, which can ultimately serve as a repository of necessary resources for sustaining life, notably carbon, water, and plant nutrients. Numerous biological and physicochemical solid waste processing options have been considered.
Technical Paper

Top-Level Modeling of Waste Processing and Resource Recovery Component of an ALSS

1999-07-12
1999-01-2044
Accurate, flexible, and dynamic mathematical computer modeling tools are required for the development and parametric evaluation of the various possible Advanced Life Support Systems (ALSS) configurations. Such models are expected to take a top-level approach to maximize modularity, flexibility in development, and user/developer friendliness. Two approaches are taken for modeling the WPRR component of an ALSS: an object oriented approach coded in Java and a SIMULINK model. Each model exhibits distinct properties for the interchange of technologies, startup requirements, and hardware/software requirements, but are anticipated to provide successful ALSS models.
Technical Paper

Object Oriented Tool for ALS Project Analysis on the Internet

1998-07-13
981753
As ALS goals branch out to extended missions to the moon and Mars, concurrent science and engineering projects take center stage in the development of new ALS technology. It is necessary to optimize the interdisciplinary research activities in order to ensure ALS research goals are met in a timely manner, and to guarantee the reliability of future long term missions. The SSM team of the NJ-NSCORT has developed an internet software platform capable of performing a systems level analysis of the ALS research activity. The information produced by the analysis can assist ALS researchers in the streamlining of research activity.
X