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In this paper, we introduce the use of ontologies to implement the information developed and organized by resource planning tools into standard project management documents covering integrated cost, resource modeling and analysis, and visualization. The basic upper ontology used for NASA Space Operations is explained and the results obtained are discussed. This ontology-centered approach is looking for tighter connections between software, hardware, and systems engineering.

The photocatalytic oxidation of VOCs was investigated using a novel countercurrent flow reactor designed to enable the treatment of toluene present in the gas and the aqueous phases simultaneously. The reactor was packed with silica-titania composites commingled with plastic pall rings. Using this mixed packing style was advantageous as it resulted in a higher UV penetration throughout the reactor. The average UV intensity in the reactor was determined to be 220 μW/g irradiated TiO2. It was found that under dry conditions, the STCs had a high adsorption capacity for toluene; however, this adsorption was completely hindered by the wetting of the STCs when the two phases were flowing simultaneously. The destruction of toluene in the aqueous phase was determined to follow a linear trend as a function of the contaminant concentration.

Silica-titania composites (STC), a novel sorbent and photocatalytic technology developed at the University of Florida in Gainesville, Florida have been evaluated for removal of volatile organic compounds (VOCs) from aircraft cabin air. Currently, activated carbon filters are used, but must be replaced frequently due to their limited adsorption capacity. These filters must be disposed of and cannot be regenerated and reused. The STC technology is a significant improvement upon the current control technology because of its high adsorption capacity and the ability to regenerate via photocatalytic oxidation (PCO). When the STC sorbent is irradiated with UV, adsorbed VOCs are mineralized to CO2 and H2O and the material is regenerated and ready for reuse multiple times.

A sub-scale testbed for characterizing the dynamic performance of regenerable adsorbents for filtering trace contaminants (TCs) from cabin atmospheres was built and tested. Regenerable adsorbents employed in pressure-swing adsorption (PSA) systems operate in a dynamic environment, where they undergo repeated loading / regeneration cycles. Adsorbents have a given chemical specificity for non-methane TCs depending on their composition, and on the humidity and temperature at which they operate. However, their ability to filter TCs is also affected by contact time, cycle time, regeneration vacuum quality and thermal conditioning.

Precision glass molding process is an attractive approach to manufacture small precision optical lenses in large volume over traditional manufacturing techniques because of its advantages such as low cost, fast time to market and being environment friendly. In this paper, we present a physics-based computational tool that predicts the final geometry of the glass element after molding process using the finite element method. Deformations of both glass and molds are considered at three different stages: heating, molding, and cooling. A 2D axisymmetric finite element model is developed to model the glass molding process. The proposed modeling technique is more efficient than the all-in-one modeling technique. The molds are assumed to be rigid, except for thermal expansion, at all time and glass treated as a flexible body during the compression. Details on identifying material parameters, modeling assumptions, and simplifications are discussed.

The partial electrochemical reduction of carbon dioxide (CO2) using ceramic oxygen generators (COGs) is well known and widely studied. Conventional COGs use yttria-stabilized zirconia (YSZ) electrolytes and operate at temperatures greater than 700 °C. Operating at a lower temperature has the advantage of reducing the mass of the ancillary components such as insulation and heat exchangers (to reduce the COG oxygen output temperature for comfortable inhalation). Moreover, complete reduction of metabolically produced CO2 (into carbon and oxygen) has the potential of reducing oxygen storage weight if the oxygen can be recovered. Recently, the University of Florida developed novel ceramic oxygen generators employing a bilayer electrolyte of gadolinia-doped ceria and erbia-stabilized bismuth oxide (ESB) for NASA's future exploration of Mars.

The removal of volatile organic compounds (VOCs) from the air aboard spacecrafts is necessary to maintain the health of crewmembers. The use of photocatalysis has proven effective for the removal of VOCs. A majority of studies have focused on thin films, which have a low adsorption capacity for contaminants and intermediate oxidation byproducts. Thus, this study investigates the use of adsorbent materials impregnated or coated with titania to: (1) provide a system that can remove VOCs for a period of time in the absence of UV irradiation to reduce power requirements and/or offer contaminant removal in the event of lamp failure and (2) improve the photocatalytic oxidation efficiency by concentrating VOCs and intermediate oxidation byproducts near the surface of the photocatalyst. Two adsorbent materials (porous silica gel and BioNuchar120 activated carbon) and glass beads were tested as catalyst supports for the destruction of a target VOC, in this case methanol (Co = 50 ppmv).

Previous work demonstrated that the Photo-Cat® developed by Purifics is capable of reducing the total organic carbon (TOC) concentration of 51 mg/L to below 0.5 ppm using Degussa P25 titanium dioxide (TiO2) as a photocatalyst. The work also showed that ammonium bicarbonate had a detrimental effect on the rate of photocatalytic oxidation, but did not prevent the system from reaching the potable water specification. Nanometer sized Degussa P25 is very popular and quite frequently used as a benchmark of performance in literature, but it may not be the most effective for oxidizing all waste streams. It is critical that each component of the water recovery system be optimized for power consumption and the effectiveness of the photocatalyst plays an important role in accomplishing this.

High speed machining of aluminum and magnesium helicopter gearcases was experimentally demonstrated to be five times more productive than contemporary conventional commercial practice for suitable operations. Appropriate techniques and performance characteristics are discussed for face milling, endmilling and planetary milling operations. Potential problem areas, such as surface characteristics and machine tool performance requirements are discussed.

Finding a manner to effectively filter water to the purest standards is an ongoing battle for various sectors of science. We present a set of experiments that will report the preparation of the photocatalytic component of our composite particle via sol-gel coatings with titanium n-butoxide with subsequent heat treatment at 500°C for three hours in Argon. Our ultimate goal is to create a particle with regenerative capabilities along with a surface enhanced Raman scattering effect. Characterization techniques were performed using SEM-EDS, and XRD.

The technical feasibility of applying anaerobic digestion for reduction and stabilization of the organic fraction of solid wastes generated during space missions was investigated. This process has the advantages of not requiring oxygen or high temperature and pressure while producing methane, carbon dioxide, nutrients, and compost as valuable products. High-solids leachbed anaerobic digestion employed here involves a solid-phase fermentation with leachate recycle between new and old reactors for inoculation, wetting, and removal of volatile organic acids during startup. After anaerobic conversion is complete, the compost bed may be used for biofiltration and plant growth medium. The nutrient-rich leachate may also be used as a vehicle for nutrient recycle. Physical properties of representative waste feedstocks were determined to evaluate their space requirements and hydraulic leachability in the selected digester design.

The main principles of artificial atmospheric design for a Martian Greenhouse (MG) are described based on: 1. Cost-effective approach to MG realization; 2. Using in situ resources (e.g. CO2, O2, water); 3. Controlled greenhouse gas exchange by using independent pump in and pump out technologies. We show by mathematical modeling and numerical estimates based on reasonable assumptions that this approach for Martian deployable greenhouse (DG) implementation could be viable. A scenario of MG realization (in terms of plant biomass/photosynthesis, atmospheric composition, and time) is developed. A list is given of technologies (natural water collection, MG inflation, oxygen collection and storage, etc.) that are used in the design. The conclusions we reached are: 1. Initial stocks of oxygen and water probably would be required to initiate plant germination and growth; 2. Active control of MG ventilation could provide proper atmospheric composition for each period of plant growth; 3.

A stiffness requirement for high speed milling machines is determined by examining the stiffness of current generation high speed spindles. The desire for stability against chatter dictates that the stiffness of the machine structure and drives, when reflected to the tool tip exceed the spindle/tool holder/tool stiffness. The stiffness characteristics of a classical serial machine tool designed expressly for high speed milling are shown. Another potential design for high speed machining applications, the parallel kinematic or hexapod structure is also examined. It is found that hexapod structures exhibit lower structural stiffness than can be achieved in serial machines when using the same drive components. Furthermore, the stiffness of the hexapod structure varies widely across the workspace, leading to difficulties in control and limiting the achievable accuracy.

The veiling glare effect in automotive vehicles consists of diffuse and specular scattering of sunlight onto and from the windshield. This effect occurs over a wide range of solar elevation angles and increases with increased degree of inclination of the windshield. Thus its effect on visual acuity must be considered in automotive design. The present research on the subject of veiling glare only addresses scattering from a clean windshield and ignores the larger effect of scattering from dust, dirt or haze on the front and back faces of the windshield since the latter is operator dependent (can be removed by cleaning the windshield). In this paper, we present an analysis of autmotive veiling glare that takes into account windshield reflectivity without and with coatings, and the characteristics of dashboard cover materials.

Efforts to develop sensor and control system technology to monitor air quality for life support have resulted in the development and preliminary testing of a concept based on expert systems and ion trap mass spectrometry (ITMS). An ITMS instrument provides the capability to identify and quantitate a large number of suspected contaminants at trace levels through the use of a variety of multidimensional experiments. An expert system provides specialized knowledge for control, analysis, and decision making. The system is intended for real-time, on-line, autonomous monitoring of air quality. The key characteristics of the system, performance data and analytical capabilities of the ITMS instrument, the design and operation of the expert system, and results from preliminary testing of the system for trace contaminant monitoring are described.

Separation of roughly equal volume mixtures of methanol and gasoline into two phases at low temperature may cause problems for vehicles that are designed to operate on these mixtures. Cosolvent alcohols (C2-C12) and surfactants were evaluated as additives for enhancing phase stability at -25°C of a blend containing SO volume percent methanol, 40 percent isooctane, and 10 percent toluene (simulating a 50/50 methanol/gasoline mixture). For alcohol cosolvents, the amount required decreased with increasing carbon number (number of carbon atoms per molecule) from about 50 percent with C2 to about 6 percent for C8 through C12 A simple cost analysis indicated that decanol (C10) provided the minimum treatment cost for preventing separation at -25°C: $0.13/galloπ. Of the various commercial nonionic surfactants and various anionic fatty acid surfactants evaluated, only palmitic acid (C16) showed good effectiveness.