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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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At least 397 records · Page 22

A review of recent activities in the NASA CELSS program

A CELSS (Controlled Ecological Life Support System) is a device that utilizes photosynthetic organisms and light energy to regenerate waste materials into oxygen and food for a crew in space. The results of theoretical and practical studies conducted by investigators within the CELSS program suggest that a bioregenerative life support system can be a useful and effective method of regenerating consumable materials for crew sustenance. Experimental data suggests that the operation of a CELSS in space will be practical if plants can be made to behave predictably in the space environment. Much of the work currently conducted within the CELSS program centers on the biological components of the CELSS system. The work is particularly directed at ways of achieving high efficiency and long term stability of all components of the system. Included are explorations of the conversion of nonedible cellulose to edible materials, nitrogen fixation by biological and chemical methods, and methods of waste processing. It is the intent of the presentation to provide a description of the extent to which a bioregenerative life support system can meet the constraints of the space environment, and to assess the degree to which system efficiency and stability can be increased during the next decade.

Macelroy, R. D.↗

Optimizing green infrastructure placement under precipitation uncertainty

Increased urbanization, infrastructure degradation, and climate change threaten to overwhelm stormwater systems across the nation, rendering them ineffective. Green Infrastructure (GI) practices are low cost, low regret strategies that can contribute to urban runoff management. However, questions remain as to how to best distribute GI practices through urban watersheds given precipitation uncertainty and the variable hydrological responses to them. We develop stochastic programming models to determine the optimal placement of GI practices across a set of candidate locations in a watershed to minimize the total expected runoff under medium-term precipitation uncertainties. Specifically, we first develop a two-stage stochastic programming model. Next, we reformulate this model using perturbed parameters to reduce the requisite computational time and extend it to multi-stage. In addition, we introduce constraints that allow for incorporating sub-catchment-level runoff reduction considerations. Furthermore, we account for hydrological connectivity in the watershed using an underlying acyclic connectivity graph of sub-catchments and incorporate various practical considerations into the models. In addition, we develop a systemic approach to downscale the existing daily precipitation projections into hourly units and efficiently estimate the corresponding hydrological responses. These advancements are brought together in a case study for an urban watershed in a mid-sized city in the U.S., where we perform sensitivity analyses, evaluate the importance of the considered constraints, and provide insights.

54 ENVIRONMENTAL SCIENCES↗

A Community for Polar Early Career Researchers Engaging With the Interagency Arctic Research Policy Committee

The Interagency Arctic Research Policy Committee (IARPC) is tasked with implementation of the Arctic Research Plan (ARP) by coordinating representatives from federal and state agencies, academic, industry, and Indigenous partners with interests in Arctic research. IARPC is organized into several collaboration teams and discipline-specific communities of practice that interface on the IARPC Collaborations website. The Early Career Community of Practice (ECCoP) is one such community that was established to promote the research of early career researchers (ECR) and increase ECR engagement with the ARP, program managers, collaboration teams, and communities of practice. The ECCoP has grown to develop regular newsletters promoting recent ECR research publications ad sharing training, job, funding, and collaboration opportunities relevant to community members at all life stages that self-identify as ECRs. Within IARPC, the ECCoP continues to promote ECR participation in monthly community of practice meetings and webinars and to report on ECR efforts that contribute to deliverables of the ARP Biennial Implementation Plan. Recent activity of the ECCoP includes developing an annual survey of the ECR cohort on IARPC to follow change in demographics over time and to identify community needs to improve diversity and inclusion in the polar research space and to address gaps in training needs for ECRs.

Katy Smith↗

Apollo Metrology Program

This paper introduces the metrology requirements in the recently published Apollo Program handbook, NHB 5400.2, entitled, 'Apollo Metrology Requirements Manual.' The major elements and control practices required for a comprehensive metrology system are identified. The elements are presented to you with sufficient detail of control practices to provide the scope of a total metrology program. The Manual is for implementation by the Apollo Space Flight Centers, their testing sites and contractors. The benefits of implementing these requirements are equally applicable to any Government or industry standards and calibration laboratory operations.

Porter, W. A.↗

NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 54: The technical communications practices of engineering technology students: Results of the NASA/DOD Aerospace Knowledge Diffusion Research Project phase 3 student surveys

Engineering technology programs are characterized by their focus on application and practice, and by their approximately 50/50 mix of theory and laboratory experience. Engineering technology graduates are employed across the technological spectrum and are often found in areas that deal with application, implementation, and production. Yet we know very little about the communications practices and information-use skills of engineering technology students. In this paper, we report selected results of an exploratory study of engineering technology students enrolled in three U.S. institutions of higher education. Data are presented for the following topics: career goals and aspirations; the importance of, receipt of, and helpfulness of communications and information-use skills instruction; collaborative writing; use of libraries; and the use of electronic (computer) networks.

Pinelli, Thomas E.↗

Improving Mathematical Exposition of an Industrial-Scale Linear Program

Industrial-scale models require considerable setup time; hence, once built, they are used in myriad ways to consider closely related cases. In practice, the code for these models frequently evolves without appropriate notational choices, largely as a result of the lengthy development time of, and the number of individuals contributing to, their formulation. This leads to inefficiencies and obfuscates model structures that might be leveraged to expedite solutions. In this paper, we advocate for an emerging literature on model formulation “best practices” and present the reformulation of a widely used industrial-scale linear program. The efficient mathematical expression of this linear program, used to plan capacity expansion in the energy sector, allows for greater transparency of model structures and enhanced ability to identify computational performance improvements, as well as a lucid interpretation of its solutions. This type of formulation is employed in several mathematical programming courses at our university as an example of the advantages of best practices; the model more broadly is used widely to inform policy in the U.S. energy sector.

97 MATHEMATICS AND COMPUTING↗

Current Status of Human Resource Training Program for Fostering RIBiomics Professionals

RI-Biomics is a state-of-the-art radiation fusion technology for evaluating in-vivo dynamics such as absorption, distribution, metabolism and excretion (ADME) of new drug candidates and biomaterials using radioisotope (RI), and quantitative evaluation of their efficacy via molecular imaging techniques and animal models. The RI-Biomics center is the sole comprehensive research and experiment complex in Korea that can simultaneously perform the radio-synthesis of drug candidate with radioisotope, analysis, and molecular imaging evaluation with animal model. Molecular imaging techniques, including nuclear imaging (SPECT and PET), near-infrared fluorescent (NIRF) imaging, and magnetic resonance imaging (MRI), are the cutting-edge technologies for evaluating drug candidates. Since they allow in vivo real-time imaging of the diseased site, monitoring the biodistribution of drug and determining the optimal therapeutic efficacy following treatments, we have integrated RI-ADME and molecular imaging to provide useful information for drug evaluation and to accelerate the development of new drugs and biomaterials. The RI-Biomics center was established with total investment of 18 million $ during four years from 2009 to 2012 in order to develop a comprehensive analyzing system using RI for new drug development as an axis for national growth in the next generation. The RI-Biomics center has labeling synthesis facility for the radiosynthesis of drug candidate with radioisotope such as Tc-99m, I-125, I-131, F-18, H-3 and C-14 using hot cell. It also includes RI-general analysis facilities, such as Radio-HPLC, LC/MS, GC/MS, gamma counter that can analyzing the radio-synthesized materials, and animal image analysis facilities that developed small animal imaging equipment such as SPECT/PET/CT, 7 T MRI, in-vivo optical imaging system and others. In order to achieve the system to verify safety and effectiveness of the new drugs using RI, it is necessary to establish a human resource training program for fostering RI-Biomics professionals in the following key fields; (1) Radio-pharmaceuticals synthesis and labeled compound development, (2) Development of RI-ADME in the living object and image assessment technology. Personnel training program that carries out theoretical education and practical training in the field related to RI-Biomics in parallel is being conducted. Internship training for university students has been administered twice already while educational program for the existing professionals in the RI-Biomics field will be carried out during the summer of 2014. The human resource training program for combination of RIADME and different molecular imaging techniques can offer synergistic advantages to facilitate understanding RIADME and fostering RI-ADME professionals. (authors)

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Robot Display and Control program (ROBDAC)

The ROBOT display and control program (ROBDAC) to be written for the Adage 340 computer is designed to communicate with the Univac 1110 computer with the aid of the graphic support communications programs. ROBDAC and the Adage computer act as an input/output device for the program ROBOT, which is run on the Univac 1110. ROBDAC controls the input to ROBOT by displaying images of the inputs, providing an editing technique for these inputs, shipping the input data to the Univac, and then commanding ROBOT to start execution. The output is done in a similar manner after receiving the output data from the Univac. This data will be displayed numerically as well as by plotted graphs. All of the input/output will be done interactively with practically 'finger tip' control. A general program flow diagram of ROBDAC is included.

Stewart, W. A.↗

Recommendations on Use of Commercial-Off-The-Shelf (COTS) Electrical, Electronic, and Electromechanical (EEE) Parts for NASA Missions

The NASA Electronic Parts & Packaging Program Manager, requested a NASA Engineering and Safety Center independent assessment to summarize Commercial Crew Program and NASA Centers’ current and best practices, and lessons learned, on use of commercial-off-the-shelf (COTS) for all mission risk classifications, and provide recommendations that could lead to future NASA Electronic Parts and Packaging Program and/or Agency guidance on COTS parts. This document contains the outcome of the assessment.

Commercial-Off-The-Shelf↗

Personnel Qualification and Certification Program in Pressure Decay Leak Testing on the RT-100 Type (B) Cask - 17229

The requirements for qualifications and certification of leak test personnel on Type (B) shipping casks have been more clearly defined with the recent release of ANSI N14.5-2014, Leak Tests on Radioactive Packages for Shipment. The latest version creates a standardized approach for qualifying and certifying personnel to conduct pre-shipment leakage tests on Type (B) packages. The U.S Nuclear Regulatory Commission (NRC) is currently updating the Regulatory Guide R.G 7.4, Leakage Tests on Packages for shipment of Radioactive Material, to endorse ANSI N14.5-2014. According to ANSI N14.5-2014, leakage testing shall be performed in accordance with written procedures by qualified and certified personnel in accordance with the requirements of ASNT SNT-TC-1A-2006, Recommended Practice for Personnel Qualification and Certification in Nondestructive Testing. This is a significant modification to the old standard, ANSI N14.5-1997, which simply states that pressure leak testing shall be conducted by trained and certified personnel without reference to any specific certification standards or regulations. SNT-TC-1A published by the American Society for Nondestructive Testing (ASNT) has several advantages to employers; namely, it allows for a Limited NDT Level II certification program. Limited certifications are especially valuable for personnel who possess limited experience and wish to become a certified Limited NDT Level II in a specific technique on a specific cask using a specific procedure and equipment. Robatel Technologies recently developed a comprehensive qualification and training program based on the recommendations of SNT-TC-1A for Exelon Corporation to certify their employees to a Limited NDT Level II in Pressure Decay Leak Testing on the RT-100 Cask. The project scope included the development of a training and qualification program (Written practice), writing a pressure decay leak test procedure, the design of a pressure decay leak test manifold, and the delivery of classroom training. The written practice outlines the requirements to ensure that personnel participating in the program have the necessary qualification, experience, and training to become certified in the leak test method. The program will give Exelon the liberty to conduct their own leak testing on the RT- 100 without the need to rely on outside resources for leak testing. When fully implemented, the program is expected to improve productivity and eliminate schedule delays, along with substantial economic benefits. Following the appropriate standards and industry best practices, the project was successfully completed and scheduled to be fully implemented by Exelon's Nuclear Stations by the end of 2016. (authors)

07 ISOTOPE AND RADIATION SOURCES↗

DOE Challenge Home Multifamily Development - Mixed Climate

The U.S. Department of Energys Zero Energy Ready Home (ZERH) recognition program builds upon the building science requirements of ENERGY STAR Certified Homes, Version 3 and best practices tested by the Building America research and demonstration program. Multifamily units (units in buildings with five or more apartments) comprise an increasingly important segment in the U.S. new housing market. Over the past 30 years, this segment has averaged 24% of residential building permits and since the recession in 2008 averages 34% of new residential building permits. This study analyses two multifamily homes, one townhouse and one apartment. The study looks to improve the efficiency of these homes to meet ENERGY STAR standards. Apartment - 2 bedroom apartment unit Townhome - 3 bedroom townhome unit

Array↗

A study of the dynamics of rotating space stations with elastically connected counterweight and attached flexible appendages. Volume 1: Theory

The formulation of a mathematical model for predicting the dynamic behavior of rotating flexible space station configurations was conducted. The overall objectives of the study were: (1) to develop the theoretical techniques for determining the behavior of a realistically modeled rotating space station, (2) to provide a versatile computer program for the numerical analysis, and (3) to present practical concepts for experimental verification of the analytical results. The mathematical model and its associated computer program are described.

Austin, F.↗

Annual report to the NASA Administrator by the Aerospace Safety Advisory Panel. Part 2: Space shuttle program. Section 1: Observations and conclusions

The NASA and contractor management systems, including policies, practices, and procedures for the development of critical systems, subsystems and integration of the program elements, were investigated. The technical development status of critical systems, subsystems, and interfaces is presented. Space shuttle elements were qualified as to potential risks and hazards. The elements included the orbiter, external tanks, main engine, solid rocket boosters, and the ground support facilities.

Source record↗

Solid-propellant rocket motor internal ballistics performance variation analysis, phase 5

The results of research aimed at improving the predictability of internal ballistics performance of solid-propellant rocket motors (SRM's) including thrust imbalance between two SRM's firing in parallel are presented. Static test data from the first six Space Shuttle SRM's is analyzed using a computer program previously developed for this purpose. The program permits intentional minor design biases affecting the imbalance between any two SMR's to be removed. Results for the last four of the six SRM's, with only the propellant bulk temperature as a non-random variable, are generally within limits predicted by theory. Extended studies of internal ballistic performance of single SRM's are presented based on an earlier developed mathematical model which includes an assessment of grain deformation. The erosive burning rate law used in the model is upgraded and made more general. Excellent results are obtained in predictions of the performances of five different SRM's of quite different sizes and configurations. These SRM's all employ PBAN type propellants with ammonium perchlorate oxidizer and 16 to 20% aluminum except one which uses carboxyl terminated butadiene binder. The only non-calculated parameters in the burning rate equations that are changed for the different SRM's are the zero crossflow velocity burning rate coefficients and exponents. The results, in general, confirm the importance of grain deformation. The improved internal ballistic model makes practical development of an effective computer program for application of an optimization technique to SRM design which is also demonstrated. The program uses a pattern search technique to minimize the difference between a desired thrust-time trace and one calculated based on the internal ballistic model.

Sforzini, R. H.↗