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Results for “beneficial reuse”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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Water diffusion membranes 3 (pervaporation and heat rejection through composite membranes)

The problem of waste management in space is discussed for manned space flight. It is shown that such waste can be accounted for in one of four ways: (1) the waste may be dumped into space; (2) it may be accumulated for return to earth; (3) the waste may be separated into two fractions, one fraction (water) to be dumped into space and the remaining portion to be returned to earth; or (4) the waste components may be beneficially reused.

Cabasso, I.↗

A Framework for Assessing the Reusability of Hardware (Reusable Rocket Engines)

Within the space flight community, reusability has taken center stage as the new buzzword. In order for reusable hardware to be competitive with its expendable counterpart, two major elements must be closely scrutinized. First, recovery and refurbishment costs must be lower than the development and acquisition costs. Additionally, the reliability for reused hardware must remain the same (or nearly the same) as "first use" hardware. Therefore, it is imperative that a systematic approach be established to enhance the development of reusable systems. However, before the decision can be made on whether it is more beneficial to reuse hardware or to replace it, the parameters that are needed to deem hardware worthy of reuse must be identified. For reusable hardware to be successful, the factors that must be considered are reliability (integrity, life, number of uses), operability (maintenance, accessibility), and cost (procurement, retrieval, refurbishment). These three factors are essential to the successful implementation of reusability while enabling the ability to meet performance goals. Past and present strategies and attempts at reuse within the space industry will be examined to identify important attributes of reusability that can be used to evaluate hardware when contemplating reusable versus expendable options. This paper will examine why reuse must be stated as an initial requirement rather than included as an afterthought in the final design. Late in the process, changes in the overall objective/purpose of components typically have adverse effects that potentially negate the benefits. A methodology for assessing the viability of reusing hardware will be presented by using the Space Shuttle Main Engine (SSME) to validate the approach. Because reliability, operability, and costs are key drivers in making this critical decision, they will be used to assess requirements for reuse as applied to components of the SSME.

Childress-Thompson, Rhonda↗

A Framework for Assessing the Reusability of Hardware (Reusable Rocket Engines)

Within the space flight community, reusability has taken center stage as the new buzzword. In order for reusable hardware to be competitive with its expendable counterpart, two major elements must be closely scrutinized. First, recovery and refurbishment costs must be lower than the development and acquisition costs. Additionally, the reliability for reused hardware must remain the same (or nearly the same) as "first use" hardware. Therefore, it is imperative that a systematic approach be established to enhance the development of reusable systems. However, before the decision can be made on whether it is more beneficial to reuse hardware or to replace it, the parameters that are needed to deem hardware worthy of reuse must be identified. For reusable hardware to be successful, the factors that must be considered are reliability (integrity, life, number of uses), operability (maintenance, accessibility), and cost (procurement, retrieval, refurbishment). These three factors are essential to the successful implementation of reusability while enabling the ability to meet performance goals. Past and present strategies and attempts at reuse within the space industry will be examined to identify important attributes of reusability that can be used to evaluate hardware when contemplating reusable versus expendable options. This paper will examine why reuse must be stated as an initial requirement rather than included as an afterthought in the final design. Late in the process, changes in the overall objective/purpose of components typically have adverse effects that potentially negate the benefits. A methodology for assessing the viability of reusing hardware will be presented by using the Space Shuttle Main Engine (SSME) to validate the approach. Because reliability, operability, and costs are key drivers in making this critical decision, they will be used to assess requirements for reuse as applied to components of the SSME.

Childress-Thompson, Rhonda↗

Engineering design knowledge recycling in near-real-time

It is hypothesized that the capture and reuse of machine readable design records is cost beneficial. This informal engineering notebook design knowledge can be used to model the artifact and the design process. Design rationale is, in part, preserved and available for examination. Redesign cycle time is significantly reduced (Baya et al, 1992). These factors contribute to making it less costly to capture and reuse knowledge than to recreate comparable knowledge (current practice). To test the hypothesis, we have focused on validation of the concept and tools in two 'real design' projects this past year: (1) a short (8 month) turnaround project for NASA life science bioreactor researchers was done by a team of three mechanical engineering graduate students at Stanford University (in a class, ME210abc 'Mechatronic Systems Design and Methodology' taught by one of the authors, Leifer); and (2) a long range (8 to 20 year) international consortium project for NASA's Space Science program (STEP: satellite test of the equivalence principle). Design knowledge capture was supported this year by assigning the use of a Team-Design PowerBook. Design records were cataloged in near-real time. These records were used to qualitatively model the artifact design as it evolved. Dedal, an 'intelligent librarian' developed at NASA-ARC, was used to navigate and retrieve captured knowledge for reuse.

Leifer, Larry↗

Certification of Ada parts for reuse

One of the claims made by proponents of Ada is that Ada software is highly reusable. The fact that specifications are compiled and accessible would make reusability seem easily achievable. However, specifications give only a limited amount of information about a package; moreover, a specification cannot help determine whether a package worked, or how well it worked. This problem has led to the concept of certifying Ada parts for reuse; that is, determining the worthiness of a part as a reusable component. Issues that are critical to reuse are addressed: the characterization of part performance, design for reuse, and correct utilization of parts. Current areas of study beneficial in the development of a certification process are then addressed.

Hansen, Gregory A.↗

Orbital transfer vehicle launch operations study. Volume 1: Executive summary

The purpose was to use the operational experience at the launch site to identify, describe and quantify the operational impacts of the various configurations on the Kennedy Space Center (KSC) and/or space station launch sites. Orbital Transfer Vehicle (OTV) configurations are being developed/defined by contractor teams. Lacking an approved configuration, the KSC Study Team defined a Reference Configuration to be used for this study. This configuration then become the baseline for the identification of the facilities, personnel and crew skills required for processing the OTV in a realistic manner that would help NASA achieve the lowest possible OTV life cycle costs. As the study progressed, researchers' initial apraisal that the vehicle, when delivered, would be a sophisticated, state-of-the-art vehicle was reinforced. It would be recovered and reused many times so the primary savings to be gained would be in the recurring-cycle of the vehicle operations--even to the point where it would be beneficial to break from tradition and make a significant expenditure in the development of processing facilities at the beginning of the program.

Source record↗

Developing a Standard for Earth Observation Data Preservation Content - A Path to Future Usability

For datasets to be usable, many pieces of information in addition to the data themselves are essential. During the active parts of the lifecycle of dataset generating projects, the needed information is usually accessible through individuals familiar with the various aspects of the projects. However, the utility of datasets tends to outlive the lives of projects, by several decades in many cases. Thus it is essential to capture all the relevant information about the datasets, data, metadata and associate knowledge that is sufficient to read, understand, interpret and reuse the datasets, while the projects are still active. The capture and preservation should be such that the data are usable when no consultation is available from the original project participants. Identification of specific categories of content through an international standard is beneficial to the user communities of the future, so that projects involving Earth observations and generating data products can consistently plan for preservation and future usability of the project outcomes. While there are existing standards that address archival and preservation in general, there are no existing international standards or specifications today to address what content should be preserved. The standard, ISO 19165-1, titled "Geographic Information - Preservation of digital data and metadata Part 1: Fundamentals" considers geographic information preservation in general. It acknowledges that "specific content items needed to preserve the full provenance and context of the data and associated metadata depend on the needs of the designated community and types of datasets (e.g., maps, remotely sensed data from satellites and airborne instruments, physical samples). Follow-up parts to this standard may be developed detailing content items appropriate to individual disciplines." NASA proposed an extension to this standard, titled "Geographic information -- Preservation of digital data and metadata -- Part 2: Content specifications for Earth observation data and derived digital products." The development of this extension is in progress with participation by an international team representing nine countries. The purpose of this paper is to introduce this standard and report on its status.

Remote Sensing; Data Systems; Open Data;↗

Mars Conjunction Crewed Missions With a Reusable Hybrid Architecture

A new crew Mars architecture has been developed that provides many potential benefits for NASA-led human Mars moons and surface missions beginning in the 2030s or 2040s. By using both chemical and electric propulsion systems where they are most beneficial and maintaining as much orbital energy as possible, the Hybrid spaceship that carries crew round trip to Mars is pre-integrated before launch and can be delivered to orbit by a single launch. After check-out on the way to cis-lunar space, it is refueled and can travel round trip to Mars in less than 1100 days, with a minimum of 300 days in Mars vicinity (opportunity dependent). The entire spaceship is recaptured into cis-lunar space and can be reused. The spaceship consists of a habitat for 4 crew attached to the Hybrid propulsion stage which uses long duration electric and chemical in-space propulsion technologies that are in use today. The hybrid architecture's con-ops has no in-space assembly of the crew transfer vehicle and requires only rendezvous of crew in a highly elliptical Earth orbit for arrival at and departure from the spaceship. The crew transfer vehicle does not travel to Mars so it only needs be able to last in space for weeks and re-enter at lunar velocities. The spaceship can be refueled and resupplied for multiple trips to Mars (every other opportunity). The hybrid propulsion stage for crewed transits can also be utilized for cargo delivery to Mars every other opportunity in a reusable manner to pre-deploy infrastructure required for Mars vicinity operations. Finally, the Hybrid architecture provides evolution options for mitigating key long-duration space exploration risks, including crew microgravity and radiation exposure.

Merrill, Raymond G.↗

Economical Implementation of a Filter Engine in an FPGA

A logic design has been conceived for a field-programmable gate array (FPGA) that would implement a complex system of multiple digital state-space filters. The main innovative aspect of this design lies in providing for reuse of parts of the FPGA hardware to perform different parts of the filter computations at different times, in such a manner as to enable the timely performance of all required computations in the face of limitations on available FPGA hardware resources. The implementation of the digital state-space filter involves matrix vector multiplications, which, in the absence of the present innovation, would ordinarily necessitate some multiplexing of vector elements and/or routing of data flows along multiple paths. The design concept calls for implementing vector registers as shift registers to simplify operand access to multipliers and accumulators, obviating both multiplexing and routing of data along multiple paths. Each vector register would be reused for different parts of a calculation. Outputs would always be drawn from the same register, and inputs would always be loaded into the same register. A simple state machine would control each filter. The output of a given filter would be passed to the next filter, accompanied by a "valid" signal, which would start the state machine of the next filter. Multiple filter modules would share a multiplication/accumulation arithmetic unit. The filter computations would be timed by use of a clock having a frequency high enough, relative to the input and output data rate, to provide enough cycles for matrix and vector arithmetic operations. This design concept could prove beneficial in numerous applications in which digital filters are used and/or vectors are multiplied by coefficient matrices. Examples of such applications include general signal processing, filtering of signals in control systems, processing of geophysical measurements, and medical imaging. For these and other applications, it could be advantageous to combine compact FPGA digital filter implementations with other application-specific logic implementations on single integrated-circuit chips. An FPGA could readily be tailored to implement a variety of filters because the filter coefficients would be loaded into memory at startup.

Kowalski, James E.↗

VEGGIE Pillow Testing: Microbial Analysis of Cut-and-Come-Again Species Testing

With NASA focused on researching and developing technology for deep space missions, the need for a reliable supplementary food source must also be considered. For the ISS, resupplying the food source is more practical and cost effect since the facility is in low Earth orbit. However, as NASA attempts to push the frontier in space, the costs and distance for resupply will surely increase. Plants would contribute to the proportion of food and reduce the dependency on food from Earth. In addition, plants would provide oxygen production, carbon dioxide removal, and psychological benefits. As a result, a vegetable production system, VEGGIE, was developed for NASA to produce salad crops with minimal resources and study the beneficial effects. The VEGGIE pillow is a single use bag for growing crops that is used with the VEGGIE hardware. The VEGGIE pillow was tested with four different species of plants with the cut-and-come-again harvest method to determine the greatest yield. Instead of harvesting the entire plant, the harvest consisted of cutting leaves to allow the plant to regrow leaves. The harvest methods included cutting the plants weekly, bi-weekly, and monthly. A fifth plant species, radishes, was also harvested and replanted. Microbial load analysis and an ANOVA significance test were utilized. The data suggest that the two Brassica plants have the greatest yields; however, the microbial load is also greatest for the two plants per gram of fresh weight. Furthermore, the results support the reuse of pillows for multiple harvests as shown by the replanted radishes.

Nguyen, Bao-Thang↗

Integrated Waste Trade Study: Lunar Surface to Deep Space

The Logistics Reduction Project is one of NASA's technology development projects that is preparing humanity for deep space missions. Reducing the mass and volume of logistical supplies that must be carried from Earth to support the missions and their crews is the primary goal of the project. Effective ways to achieve this goal include reducing, reusing, or recycling wastes generated throughout the mission. Due to the goal of the project, waste processing technologies were analyzed for Lunar surface missions at various lengths and an 850-day Mars transit mission to evaluate the potential benefits of waste processing pertaining to each mission. The technologies assessed include trash compaction, trash-to-gas and human metabolic waste processing technologies, integrated with the baseline architectures of each mission’s habitat. The fully integrated systems were analyzed using an equivalent system mass, which is a metric that encompasses the mass, volume, power and cooling of a system, resulting in an estimate of launch mass and serving as a proxy for cost. Each system’s equivalent system mass was compared to that of the baseline waste processing system of the respective habitat, hand compaction with storage for Lunar surface missions and hand compaction with jettisoning for Mars transit, to evaluate whether the traded waste processing technology was beneficial. This analysis identifies a general trend that more sophisticated waste processing can be beneficial depending on the mission duration. For Lunar surface missions, the water recovery from waste processing can pay off over consecutive missions, due to offsetting the losses from the system via extravehicular activities. In contrast for Mars transit, the primary objective is mass removal from the spacecraft, so technologies like trash-to-gas are competitive with the baseline. Furthermore, the technologies which can recover resources from waste, such as water, may present additional advantages to an ever-changing Mars mission architecture.

Waste processing↗