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Engine out (feedgas) emissions control during cold start operations has been a major technical challenge since mandated LEV/ULEV/SULEV/PZEV regulation compliance. Cold start emissions contribute to more than 85% of total emissions in a FTP test. Unburned Hydrocarbons are mostly generated during cold starts due to a rich Air/fuel ratio strategy. Cold intake and cylinder wall surfaces do not provide a quick vaporization bed for the rich fuel, therefore un-vaporized and unburned fuel result in excessive tailpipe emissions. Utilizing fuel vapor during cold starts reduces the Hydrocarbon (HC) emissions level and minimizes the transient fuel effect process. A vapor management system must function to control the Air-to-fuel ratio of the intake charge during “cold-starts”, idle, and drive-away, or until catalyst lights off to a desired level.

Advanced ASTROCULTUR™(ADVASC) plant growth unit is a two Middeck Locker insert developed by the Wisconsin Center for Space Automation and Robotics at the University of Wisconsin-Madison. It has been developed to take advantage of plant research opportunities during the early assembly phase of the International Space Station (ISS) when the ISS resources and up/down mass availability are limited. ADVASC provides a large enclosed plant growth chamber. Control software provides precise control of environmental parameters in the plant chamber, including temperature, relative humidity, light, fluid nutrient delivery, and CO2 and ethylene concentrations. Auto-prime technologies eliminate the need for power during Shuttle ascent/descent, and therefore, greatly relieve the shortage of Shuttle resources and the ISS crew time.

Conducting research to assess the impact of microgravity environment on plant growth and development requires a research facility that has the capability to provide an enclosed, environmentally controlled plant chamber. Since plants are sensitive to a number of atmospheric gaseous materials, the chamber atmosphere must be isolated from the space vehicles' atmosphere, which typically contains high levels of CO2 and other trace contaminants and volatile organic compounds (VOCs) that can be detrimental to the plant growth. However, an enclosed chamber may result in a high concentration of ethylene, a potent hormone produced by the plants, which can accumulate to levels well above what plants are able to adapt to. The physiological effects of excessive ethylene on plant development include severe interruption of the pollen process and significant reduction of seed production.

With the help of Space Product Development Program at NASA Marshall Space Flight Center in Huntsville, Alabama, the Wisconsin Center for Space Automation and Robotics (WCSAR) at the University of Wisconsin-Madison has developed the Advanced ASTROCULTURE™ (ADVASC) plant growth unit, which is dedicated to conducting commercial or fundamental plant growth research on board the International Space Station (ISS). ADVASC provides an enclosed, environmentally controlled plant growth chamber with controlled parameters of temperature, relative humidity, light intensity, fluid nutrient delivery, and CO2 and hydrocarbon (ethylene) concentrations. Auto-prime technology eliminates the need for electrical power during Shuttle ascent/descent, and therefore greatly relieves the shortage of Shuttle resources and ISS crew time. State-of-the-art control software combined with fault tolerance and recovery algorithm significantly increases overall system robustness and efficiency.

The assembly of the International Space Station (ISS) as a permanent experimental outpost has boosted the potential for quality plant research in space. To take advantage of this orbital laboratory, the Wisconsin Center for Space Automation and Robotics (WCSAR) at the University of Wisconsin-Madison developed a plant growth facility capable of supporting plant growth in microgravity. Using this Advanced Astroculture (ADVASC) facility, an experiment was conducted with the objective to grow Arabidopsis thaliana plants from seed to seed on the ISS. Seeds were successfully germinated and grown on the ISS in ADVASC from May 10th until the end of June 2001. This experiment demonstrated that ADVASC is capable of providing environment conditions suitable for plant growth and development in microgravity, and that Arabidopsis thaliana does not require presence of gravity for growth and development.