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NASA NTRS2024

Freddie Software Security Patching

Software applications become more complicated over time as they depend on many third-party, open-source libraries. The Freddie Platform Services team actively improves software security by addressing software bugs and vulnerabilities that negatively impact software applications, especially those providing real-time operations and services for the federal partners and industries. In order to detect bugs and patch vulnerabilities in software development and maintenance cycles, an automated and systematic approach is needed. This document describes what bugs and vulnerabilities are, and how they can be detected by using static code analyzers and software composition analysis tools. Once vulnerabilities are detected, the patching approaches, such as upgrading direct and transitive dependencies and loading custom classes first, are presented together with their strengths and weaknesses. In addition, patching walkthrough, example code, lessons learned throughout the vulnerability patching process and the recommended practices are discussed.

Chok Fung Lai↗

DOE OSTI2020

Using Machine Learning to Predict Future Temperature Outputs in Geothermal Systems

Optimizing the power output, and economic value, of geothermal power plants over decades of operation is a major challenge in renewable energy. Optimizing the output requires the ability to predict the mass flow rates and the output temperatures of production wells based on the inputs of injection wells, as well as the time history of the system. Machine Learning (ML) that incorporates the known physics of geothermal systems is one possible solution to this challenge. In this work, we explore the ability of ML algorithms to predict future temperature outputs based on historical data. Considering the challenges with obtaining an empirical dataset from field data that is large enough to enable reliable ML, we propose an alternate approach: developing a high-fidelity reservoir model and using computational resources to build a dataset that enables ML. As a first step towards achieving this goal, we present preliminary results from applying ML to predict the temperature timeseries of simple modeled geothermal systems. We describe the application of relevant state-of-the-art ML approaches, such as the Long Short-Term Memory (LSTM) networks and Convolutional Neural Networks (CNN), to extract temporal structures in the model data. We assess the accuracy of the forecasts we obtain, compare the selected approaches, and share the lessons learned that would inform the process of training and utilizing ML algorithms for larger and more complex geothermal systems.

GEOTHERMAL ENERGY↗

DOE OSTI2024

Successful International Validation Test Shipment of the PIP-II HB650 Cryomodule Transportation System

The PIP-II Project will receive fully assembled cryomodules from CEA and STFC-UKRI as in-kind contributions. Damage to these cryomodules during transport is understood to be a significant risk to the project, so an extensive testing and validation program has been executed to mitigate this risk. The centerpiece of this effort was the successful shipment, from FNAL to STFC-UKRI and back, of a prototype HB650 cryomodule with cold testing before and after shipment to verify no functionality changes from shipment. Building on an escalating test transport program, the prototype cryomodule was shipped to the UK and back using realistic logistics, handling, instrumentation, and planning. The process of executing this shipment, lessons learned, and plan moving forward will be presented here.

43 PARTICLE ACCELERATORS↗

NASA NTRS2005

Use of New Communication Technologies to Change NASA Safety Culture: Incorporating the Use of Blogs as a Fundamental Communications Tool

The purpose of this paper is to explore an innovative approach to culture change at NASA that goes beyond reorganizations, management training, and a renewed emphasis on safety. Over the last five years, a technological social revolution has been emerging from the internet. Blogs (aka web logs) are transforming traditional communication and information sharing outlets away from established information sources such as the media. The Blogosphere has grown from zero blogs in 1999 to approximately 4.5 million as of November 2004 and is expected to double in 2005. Blogs have demonstrated incredible effectiveness and efficiency with regards to affecting major military and political events. Consequently, NASA should embrace the new information paradigm presented by blogging. NASA can derive exceptional benefits from the new technology as follows: 1) Personal blogs can overcome the silent safety culture by giving voice to concerns or questions that are not well understood or seemingly inconsequential to the NASA community at-large without the pressure of formally raising a potential false alarm. Since blogs can be open to Agency-wide participation, an incredible amount of resources from an extensive pool of experience can focus on a single issue, concern, or problem and quickly vetted, discussed and assessed for feasibility, significance, and criticality. The speed for which this could be obtained cannot be matched through any other process or procedure currently in use. 2) Through official NASA established blogs, lessons learned can be a real-time two way process that is formed and implemented from the ground level. Data mining of official NASA blogs and personal blogs of NASA personnel can identify hot button issues and concerns to senior management. 3) NASA blogs could function as a natural ombudsman for the NASA community. Through the recognition of issues being voiced by the community and taking a proactive stance on those issues, credibility within NASA Management can be restored. For NASA to harness the capabilities of blogs, NASA must develop an Agency-wide policy on blogging to encourage use and provide guidance. This policy should describe basic rules of conduct and content as well as a policy of non-retribution and/or anonymity. The Agency must provide sever space within their firewalls, provide appropriate software tools, and promote blogs in newsletters and official websites. By embracing the use of blogs, a potential pool of 19,000 experts could be available to address each posted safety issue, concern, problem, or question. Blogs could result in real NASA culture change.

Huls, Dale thomas↗

NASA NTRS1989

Development of the XV-15 tiltrotor research aircraft - Lessons learned

The initial ground rules that guided the decision process during the initial stages of the XV-15 tiltrotor aircraft development are reviewed and reevaluated. A full flight-envelope nonlinear simulation mathematical model is outlined, along with the advantages of a multiaircraft program. Direct involvement of government engineers in all aspects of the program is considered to be beneficial, while the ejection-seat test requirement is not. Utilization of existing components - a rotor, transmissions, and engines - is analyzed, and emphasis is placed on integrated system test plans responsible for producing two reliable aircraft through a complete checkout of the aircraft subsystems before the start of the fligth program. Wind-tunnel and fatigue test requirements are presented, and the decision to go with an all mechanical control system design is addressed.

Schroers, Laurel G.↗

NASA NTRS2016

Design, Development and Hotfire Testing of Monolithic Copper and Bimetallic Additively Manufactured Combustion Chambers

NASA and industry partners are working towards fabrication process development to reduce costs and schedules associated with manufacturing liquid rocket engine components with the goal of reducing overall mission costs. One such technique being evaluated is powder-bed fusion or selective laser melting (SLM) otherwise commonly referred to as additive manufacturing. The NASA Low Cost Upper Stage Propulsion (LCUSP) program was designed to develop processes and material characterization for the GRCop-84 copper-alloy commensurate with powder bed additive manufacturing, evaluate bimetallic deposition and complete testing of a full scale combustion chamber. As part of this development, the process has been transferred to industry partners to enable a long-term supply chain of monolithic copper combustion chambers. As a direct spin off of this program, NASA is working with industry partners to further develop the printing process for the GRCop-84 material in addition to the C-18150 (CuCrZr) material. To advance the process further and allow for optimization with multiple materials, NASA is also investigating the feasibility of bimetallic additively manufactured chambers. A 1.2k sized thrust-chamber was designed and developed to compare the printing process of the GRCop-84 and C-18150 SLM materials. A series of similar MCC liners also completed development with an Inconel 625 jacket bonded to the GRcop-84 liner evaluating direct metal deposition (DMD) laser and arc-based techniques. This paper describes the design, development, manufacturing and testing of these combustion chambers and associated lessons learned throughout the design and development process.

Gradl, Paul↗

NASA NTRS1999

Launch Vehicle Design Process Description and Training Formulation

A primary NASA priority is to reduce the cost and improve the effectiveness of launching payloads into space. As a consequence, significant improvements are being sought in the effectiveness, cost, and schedule of the launch vehicle design process. In order to provide a basis for understanding and improving the current design process, a model has been developed for this complex, interactive process, as reported in the references. This model requires further expansion in some specific design functions. Also, a training course for less-experienced engineers is needed to provide understanding of the process, to provide guidance for its effective implementation, and to provide a basis for major improvements in launch vehicle design process technology. The objective of this activity is to expand the description of the design process to include all pertinent design functions, and to develop a detailed outline of a training course on the design process for launch vehicles for use in educating engineers whose experience with the process has been minimal. Building on a previously-developed partial design process description, parallel sections have been written for the Avionics Design Function, the Materials Design Function, and the Manufacturing Design Function. Upon inclusion of these results, the total process description will be released as a NASA TP. The design function sections herein include descriptions of the design function responsibilities, interfaces, interactive processes, decisions (gates), and tasks. Associated figures include design function planes, gates, and tasks, along with other pertinent graphics. Also included is an expanded discussion of how the design process is divided, or compartmentalized, into manageable parts to achieve efficient and effective design. A detailed outline for an intensive two-day course on the launch vehicle design process has been developed herein, and is available for further expansion. The course is in an interactive lecture/workshop format to engage the participants in active learning. The course addresses the breadth and depth of the process, requirements, phases, participants, multidisciplinary aspects, tasks, critical elements,as well as providing guidance from previous lessons learned. The participants are led to develop their own understanding of the current process and how it can be improved. Included are course objectives and a session-by-session outline of course content. Also included is an initial identification of visual aid requirements.

Atherton, James↗

NASA NTRS2006

Lessons Learned from Daily Uplink Operations during the Deep Impact Mission

The Deep Impact mission to comet Tempel-1 produced some of the more spectacular science results ever collected by a spacecraft. On July 4, 2005 the Deep Impact Flyby vehicle observed the Deep Impact Impactor vehicle's collision with the comet. 24 hours earlier the Flyby vehicle released the Impactor vehicle into the path of comet Tempel-1. The process to command the spacecraft was a challenge to the entire flight operations team. This paper presents an overview of the process used prepare command products for uplink and the lessons that were learned from this process.

mission operations↗

NASA NTRS2001

The Integration of COTS/GOTS within NASA's HST Command and Control System

NASA's mission critical Hubble Space Telescope (HST) command and control system has been re-engineered with commercial-off-the-shelf (COTS/GOTS) and minimal custom code. This paper focuses on the design of this new HST Control Center System (CCS) and the lessons learned throughout its development. CCS currently utilizes more than 30 COTS/GOTS products with an additional 1/2 million lines of custom glueware code; the new CCS exceeds the capabilities of the original system while significantly reducing the lines of custom code by more than 50%. The lifecycle of COTS/GOTS products will be examined including the package selection process, evaluation process, and integration process. The advantages, disadvantages, issues, concerns, and lessons learned for integrating COTS/GOTS into the NASA's mission critical HST CCS will be examined in detail. This paper will reveal the many hidden costs of COTS/GOTS solutions when compared to traditional custom code development efforts; this paper will show the high cost of COTS/GOTS solutions including training expenses, consulting fees, and long-term maintenance expenses.

Pfarr, Thomas↗

NASA NTRS2021

Lessons Learned in Remote Participant Concurrent Engineering Concept Development Studies

Team-X was born from a need to perform rapid space mission design for principal investigator-led competed proposals in the mid-1990s. Throughout the last 25 years, Team-X at the Jet Propulsion Laboratory has expanded its application of the collaborative, concurrent study approach into every facet necessary to win competed proposals. The COVID-19 pandemic of 2020 created an immediate and new constraint on these studies – the need to conduct them with remote participants, both on the client side requesting the study, but also on the provider side producing the study. This paper provides lessons learned from dozens of design studies run by Team-X at the Jet Propulsion Laboratory during the COVID-19 pandemic. These lessons span all aspects of the information infrastructure: the people, processes, procedures, methods, tools, and “facilities”. These lessons learned will have applicability post-pandemic, as they have shown how best to incorporate participants, both on the provider side, and on the client side, who cannot travel or otherwise be co-located during collaborative, concurrent study sessions.

Nash, Alfred↗

NASA NTRS2017

Development and Hot-fire Testing of Additively Manufactured Copper Combustion Chambers for Liquid Rocket Engine Applications

NASA and industry partners are working towards fabrication process development to reduce costs and schedules associated with manufacturing liquid rocket engine components with the goal of reducing overall mission costs. One such technique being evaluated is powder-bed fusion or selective laser melting (SLM), commonly referred to as additive manufacturing (AM). The NASA Low Cost Upper Stage Propulsion (LCUSP) program was designed to develop processes and material characterization for GRCop-84 (a NASA Glenn Research Center-developed copper, chrome, niobium alloy) commensurate with powder-bed AM, evaluate bimetallic deposition, and complete testing of a full scale combustion chamber. As part of this development, the process has been transferred to industry partners to enable a long-term supply chain of monolithic copper combustion chambers. To advance the processes further and allow for optimization with multiple materials, NASA is also investigating the feasibility of bimetallic AM chambers. In addition to the LCUSP program, NASA has completed a series of development programs and hot-fire tests to demonstrate SLM GRCop-84 and other AM techniques. NASA's efforts include a 4K lbf thrust liquid oxygen/methane (LOX/CH4) combustion chamber and subscale thrust chambers for 1.2K lbf LOX/hydrogen (H2) applications that have been designed and fabricated with SLM GRCop-84. The same technologies for these lower thrust applications are being applied to 25-35K lbf main combustion chamber (MCC) designs. This paper describes the design, development, manufacturing and testing of these numerous combustion chambers, and the associated lessons learned throughout their design and development processes.

Gradl, Paul R.↗

NASA NTRS2006

Importance Of Quality Control in Reducing System Risk, a Lesson Learned From The Shuttle and a Recommendation for Future Launch Vehicles

This paper presents lessons learned from the Space Shuttle return to flight experience and the importance of these lessons learned in the development of new the NASA Crew Launch Vehicle (CLV). Specifically, the paper discusses the relationship between process control and system risk, and the importance of process control in improving space vehicle flight safety. It uses the External Tank (ET) Thermal Protection System (TPS) experience and lessons learned from the redesign and process enhancement activities performed in preparation for Return to Flight after the Columbia accident. The paper also, discusses in some details, the Probabilistic engineering physics based risk assessment performed by the Shuttle program to evaluate the impact of TPS failure on system risk and the application of the methodology to the CLV.

Safie, Fayssal M.↗

NASA NTRS2017

Development and Hotfire Testing of Additively Manufactured Copper Combustion Chambers for Liquid Rocket Engine Applications

NASA and industry partners are working towards fabrication process development to reduce costs and schedules associated with manufacturing liquid rocket engine components with the goal of reducing overall mission costs. One such technique being evaluated is powder-bed fusion or selective laser melting (SLM), commonly referred to as additive manufacturing (AM). The NASA Low Cost Upper Stage Propulsion (LCUSP) program was designed to develop processes and material characterization for GRCop-84 (a NASA Glenn Research Center-developed copper, chrome, niobium alloy) commensurate with powder bed AM, evaluate bimetallic deposition, and complete testing of a full scale combustion chamber. As part of this development, the process has been transferred to industry partners to enable a long-term supply chain of monolithic copper combustion chambers. To advance the processes further and allow for optimization with multiple materials, NASA is also investigating the feasibility of bimetallic AM chambers. In addition to the LCUSP program, NASA’s Marshall Space Flight Center (MSFC) has completed a series of development programs and hot-fire tests to demonstrate SLM GRCop-84 and other AM techniques. MSFC’s efforts include a 4,000 pounds-force thrust liquid oxygen/methane (LOX/CH4) combustion chamber. Small thrust chambers for 1,200 pounds-force LOX/hydrogen (H2) applications have also been designed and fabricated with SLM GRCop-84. Similar chambers have also completed development with an Inconel 625 jacket bonded to the GRCop-84 material, evaluating direct metal deposition (DMD) laser- and arc-based techniques. The same technologies for these lower thrust applications are being applied to 25,000-35,000 pounds-force main combustion chamber (MCC) designs. This paper describes the design, development, manufacturing and testing of these numerous combustion chambers, and the associated lessons learned throughout their design and development processes.

Gradl, Paul R.↗

DOE OSTI2022

What We Learned From Analyzing 18 Million Rows of Commercial Buildings’ HVAC Fault Data

To achieve ambitious decarbonization goals it is critical that buildings operate to their full potential. Commercial HVAC systems, however, experience a wide range of operational faults, adversely affecting energy consumption, occupant comfort, and maintenance costs. Analytical tools such as fault detection & diagnostics (FDD) software identify and help diagnose these types of sensing, mechanical, or control-related faults. While significant energy savings has been documented for FDD, along with limited-scale studies on technical capabilities, there is a lack of empirical data on faults being reported by FDD tools. With FDD deployment accelerating significantly over the past decade there is an opportunity to gather and analyze data on commercial HVAC operational problems at an unprecedented scale. Such data could address many questions such as: [a] What faults are most commonly reported?; and [b] How does fault reporting vary by time of year and other possible drivers? A recent study into FDD fault reporting amassed the largest U.S. dataset of commercial HVAC air-side fault records, drawn from multi-year monitoring across over 60,000 pieces of HVAC equipment. The results of this study provide granular data on fault reporting for over 90 unique fault types. In this paper we provide an overview of the research process and highlight key findings and lessons learned. This study presents an extraordinary level of detail on FDD fault reporting characteristics across many climate zones and building types. Armed with these new insights, commercial building industry stakeholders can make better informed decisions when designing, configuring, and operating commercial HVAC systems.

Crowe, Eliot↗

NASA NTRS2024

Transitioning Sixty Years of NASA Spacesuit Knowledge Capture Lessons Learned to Searchable Knowledge Transfer Databases

Sixty years of spacesuit knowledge capture and lessons learned by spacesuit subject matter experts are documented on videos and presentations and archived with the NASA Engineering and Safety Center (NESC) Academy. The NESC Academy is a web-based platform that hosts online courses by technical experts. A process is underway to transition these decades of lessons learned from the U.S. Spacesuit Knowledge Capture Program Library into more quicky searchable databases and to proactively provide this information to those working on spacesuit projects. Hundreds of lessons learned from Project Mercury, Gemini, Apollo, Apollo- Soyuz Test Project, Skylab, Space Shuttle, International Space Station, and Artemis have been captured in a format that can be quickly searched, enabling users to find information directly applicable to their needs. Transitioning this information to a NASA wiki page will further enhance search and retrieval of data immediately useful to users. This paper provides information about how the lessons learned were determined and how to access them.

spacesuit↗

NASA NTRSDate not supplied

Transitioning Sixty Years of NASA Spacesuit Knowledge Capture Lessons Learned to Searchable Knowledge Transfer Databases

spacesuit↗

NASA NTRS1992

The Effects of Use of Civil Airworthiness Criteria on U.S. Air Force Acquisition, Test and Evaluation Practices

In response to the initiatives to streamline, not to mention comply with the Public Law for Non-Developmental Item Preference, the Department of Defense (DOD) has increased its use of commercial products. The Air Force has, over the past 15 years, been adapting Federal Aviation Administration (FAA) certified aircraft to perform many of its airlift and training missions. Counting the T-1A Jayhawk Trainer (Beechjet 400), in excess of 500 total aircraft, covering 15 different types, will have been procured since 1978. Needless to say, significant reform of the "classical" DOD and Air Force way of doing business has been necessary. Major strides have been made by the Transport Directorate of the Aircraft Program Office in the area of test and evaluation, with integrated qualification and operational testing (QT &E/QOT &E) and airworthiness certification testing by the FAA. As well, significant changes in contracting practices and the use of commercial (vice military) specifications for qualification criteria have been realized. This paper will relate some of these significant strides in "commercializing" and streamlining the DOD acquisition and test and evaluation processes. Additionally, it will review both regulatory changes made and recommended. It concludes with a compilation of lessons learned and recommendations for further streamlining of the DOD processes.

Flight Testing↗

DOE OSTI2020

Quantum biology revisited

Photosynthesis is a highly optimized process from which valuable lessons can be learned about the operating principles in nature. Its primary steps involve energy transport operating near theoretical quantum limits in efficiency. Recently, extensive research was motivated by the hypothesis that nature used quantum coherences to direct energy transfer. This body of work, a cornerstone for the field of quantum biology, rests on the interpretation of small-amplitude oscillations in two-dimensional electronic spectra of photosynthetic complexes. This Review discusses recent work reexamining these claims and demonstrates that interexciton coherences are too short lived to have any functional significance in photosynthetic energy transfer. Instead, the observed long-lived coherences originate from impulsively excited vibrations, generally observed in femtosecond spectroscopy. These efforts, collectively, lead to a more detailed understanding of the quantum aspects of dissipation. Nature, rather than trying to avoid dissipation, exploits it via engineering of exciton-bath interaction to create efficient energy flow.

59 BASIC BIOLOGICAL SCIENCES↗