42 research outputs found
Independent Orbiter Assessment (IOA): Analysis of the life support and airlock support subsystems
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. This report documents the independent analysis results corresponding to the Orbiter Life Support System (LSS) and Airlock Support System (ALSS). Each level of hardware was evaluated and analyzed for possible failure modes and effects. Criticality was assigned based upon the severity of the effect for each failure mode. The LSS provides for the management of the supply water, collection of metabolic waste, management of waste water, smoke detection, and fire suppression. The ALSS provides water, oxygen, and electricity to support an extravehicular activity in the airlock
Independent Orbiter Assessment (IOA): Assessment of the life support and airlock support systems, volume 1
The results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Life Support and Airlock Support Systems (LSS and ALSS) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the NASA FMEA/CIL baseline with proposed Post 51-L updates included. The discrepancies were flagged for potential future resolution. This report documents the results of that comparison for the Orbiter LSS and ALSS hardware. The IOA product for the LSS and ALSS analysis consisted of 511 failure mode worksheets that resulted in 140 potential critical items. Comparison was made to the NASA baseline which consisted of 456 FMEAs and 101 CIL items. The IOA analysis identified 39 failure modes, 6 of which were classified as CIL items, for components not covered by the NASA FMEAs. It was recommended that these failure modes be added to the NASA FMEA baseline. The overall assessment produced agreement on all but 301 FMEAs which caused differences in 111 CIL items
Daily UV-B treatments and elevated CO2 increases pigment concentrations and net photosynthesis of basil (Ocimum basilicum L.)
Anthropogenic emissions have greatly influenced UV-B radiation incidence and CO2 concentration globally. The interactive effects of projected incidence on crops by the end of the century need to be studied to understand the implications. The use of sunlit plant growth chambers in combination with UV-B radiation and CO2 treatments was used to identify the individual and interactive effects on basil 'Genovese' plants. Treatments included 0 and 10 kJ m−2 d−1 UV-B supplementation at ambient (437 ppm) or elevated (725 ppm) CO2 concentrations. Effects of UV-B by CO2 interactions existed for net photosynthesis, light-adapted maximal quantum efficiency, all plant pigment concentrations, and malondialdehyde. UV-B increased leaf temperature by approximately 1 °C while elevated CO2 concentrations amplified superoxide dismutase and ascorbate peroxidase activity in basil leaves. Despite deleterious impacts on plant health, UV-B radiation is essential for stimulating healthful compounds in basil. Understanding the effects when combined with elevated CO2 is necessary to improve crop production and future research
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Feasibility of developing a portable driver performance data acquisition system for human factors research: Design specifications. Volume 3
A two-phase, multi-year research program entitled ``development of a portable driver performance data acquisition system for human factors research was recently completed. The primary objective of the project was to develop a portable data acquisition system for crash avoidance research (DASCAR) that will allow driver performance data to be collected using a large variety of vehicle types and that would be capable of being installed on a given vehicle type within a relatively short-time frame. During Phase 1 a feasibility study for designing and fabricating DASCAR was conducted. In phase 2 of the research DASCAR was actually developed and validated. This technical memorandum documents the results from the feasibility study. It is subdivided into three volumes. Volume one addresses the last five items in the phase 1 research and the first issue in the second phase of the project. Volume 2 presents the related appendices. Volume three (this report) displays the design specifications developed for DASCAR during the ``develop design requirements and specifications for a portable driver performance data acquisition system`` task. Design specifications were assembled for each DASCAR element. The specifications were prepared in sufficient detail to allow a third party to use them to design, develop, procure, and subsequently construct the data acquisition system. This report also covers the background to the program
The relationship between tomato fruit growth, incidence of blossom‐end rot and phytohormone content as affected by sink/source ratio
Waterlogging Causes Early Modification in the Physiological Performance, Carotenoids, Chlorophylls, Proline, and Soluble Sugars of Cucumber Plants
Waterlogging occurs because of poor soil drainage and/or excessive rainfall and is a serious abiotic stress affecting plant growth because of declining oxygen supplied to submerged tissues. Although cucumber (Cucumis sativus L.) is sensitive to waterlogging, its ability to generate adventitious roots facilitates gas diffusion and increases plant survival when oxygen concentrations are low. To understand the physiological responses to waterlogging, a 10-day waterlogging experiment was conducted. The objective of this study was to measure the photosynthetic and key metabolites of cucumber plants under waterlogging conditions for 10 days. Plants were also harvested at the end of 10 days and analyzed for plant height (ht), leaf number and area, fresh mass (FM), dry mass (DM), chlorophyll (Chl), carotenoid (CAR), proline, and soluble sugars. Results indicated that cucumber plants subjected to the 10-day waterlogging stress conditions were stunted, had fewer leaves, and decreased leaf area, FM, and DM. There were differences in physiological performance, Chl, CAR, proline, and soluble sugars. Overall, waterlogging stress decreased net photosynthesis (A), having a negative effect on biomass accumulation. However, these decreases were also dependent on other factors, such as plant size, morphology, and water use efficiency (WUE) that played a role in the overall metabolism of the plant.</jats:p
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DASCAR sensor suite and video data system
A research program oriented toward the development of a portable data acquisition system for crash avoidance research has been conducted. This paper discusses the background to the project and the requirements for the data acquisition system. it also provides a brief system overview and describes two of the system`s five major elements, the sensor suite and the video data system, in detail. Components, functions, and specifications are covered Finally the paper addresses the central data collection/analysis facility which was assembled to manage the sensor and video data, and presents the potential uses of the data acquisition system
Waterlogging Causes Early Modification in the Physiological Performance, Carotenoids, Chlorophylls, Proline, and Soluble Sugars of Cucumber Plants
Waterlogging occurs because of poor soil drainage and/or excessive rainfall and is a serious abiotic stress affecting plant growth because of declining oxygen supplied to submerged tissues. Although cucumber (Cucumis sativus L.) is sensitive to waterlogging, its ability to generate adventitious roots facilitates gas diffusion and increases plant survival when oxygen concentrations are low. To understand the physiological responses to waterlogging, a 10-day waterlogging experiment was conducted. The objective of this study was to measure the photosynthetic and key metabolites of cucumber plants under waterlogging conditions for 10 days. Plants were also harvested at the end of 10 days and analyzed for plant height (ht), leaf number and area, fresh mass (FM), dry mass (DM), chlorophyll (Chl), carotenoid (CAR), proline, and soluble sugars. Results indicated that cucumber plants subjected to the 10-day waterlogging stress conditions were stunted, had fewer leaves, and decreased leaf area, FM, and DM. There were differences in physiological performance, Chl, CAR, proline, and soluble sugars. Overall, waterlogging stress decreased net photosynthesis (A), having a negative effect on biomass accumulation. However, these decreases were also dependent on other factors, such as plant size, morphology, and water use efficiency (WUE) that played a role in the overall metabolism of the plant
