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At least 1,153 records · Page 64

Transforming any Facility for Meeting Strict Cleanliness Requirements

Over the life of the James Webb Space Telescope (JWST), Integration & Test (I&T) has taken place in areas that needed considerable work to make the facility itself and/or the protocols used while working in the rooms suitable to meet JWST percent area coverage (PAC) and molecular accumulation requirements. In addition to normal particulate matter, JWST had a uniquely significant challenge: fibers! Fibers not only cause much higher PAC levels, but they also risk damaging the angstrom sized Near Infrared Spectrometer (NIRSpec) microshutter array (MSA), which is critical to NIRSpec instrument performance. The primary emphasis of this paper is to address particulate and fiber contamination. The success of the JWST mission required effective cleanrooms, protocols, and mitigations in non-cleanroom areas that were pressed into service to house contamination-sensitive optics and scientific instruments. Some presented profound challenges. These included: NASA’s 60-year-old Johnson Space Center (JSC) Chamber A, which had never been used for anything contamination-sensitive, and the European tropical launch facilities, which were designed to meet International Standard Organization (ISO) Class 8 processing for communication satellites. The final challenge for JWST, as if to stare us in the face and say, “I dare you to try and make me clean enough,” was preparing the 4 areas in the Centre Spatial Guyanais (CSG) Final Assembly Building (BAF) located in French Guiana, a building in which one entire side opens for Ariane 5 rocket ingress and egress. This paper will describe our initial evaluation processes and the actual work undertaken to transform even the most challenging areas into first class cleanrooms that met JWST particulate and fiber requirements.

James Webb Space Telescope↗

Improving “Domain-Relevant Metadata Requirements” for Supporting Open-Source Science Initiative

Implementation of the NASA Open-Source Science Initiative (OSSI) requires sharing of all relevant information to ensure “open reproducible science” [1]. However, there are several challenges in applying the OSSI to airborne field campaigns focused on atmospheric composition, which often involve a wide variety of in-situ measurements for trace gases, aerosol and cloud properties, meteorological parameters, and radiation fields. To ensure open reproducibility from airborne field campaigns, it is essential to obtain detailed measurement descriptions, which include the detection principle, sample procedure and treatment, and data processing and correction method. The challenge is that some information, e.g., sampling procedure and treatment, may be instrument-specific and campaign or platform-dependent. The data processing may also involve empirical corrections which may evolve over time. In addition, these details (especially operation- or campaign-specific ones) are often not given in journal publications. Given these issues, there is a need to leverage and improve the current “domain-relevant metadata requirements” to represent the measurement description in standardized metadata. These requirements can then facilitate systematic collection of measurement specific metadata and serve as a foundation to develop tools for making the information accessible and data more interoperable and usable or reusable. Here we show a review of existing metadata collections, use cases, and needs for new standards.

Sean Leavor↗

Human Landing System (HLS) Program Extravehicular Activity (EVA) Compatibility Interface Requirements Document (IRD)

The purpose of this document is to establish a set of EVA compatibility design requirements for the HLS Program. This document contains the fundamental information required for building hardware compatible with suited EVA flight crewmembers to perform EVAs. Compatibility requirements are located in section 3.0 with a gravity field applicability table provided in APPENDIX G, Human Landing System Program Applicability Matrix. Each HLS Provider will use the EHP-provided matrix in Appendix G to assess applicability to the awarded mission provider on a per-mission basis. Providers will negotiate applicability with EHP, and this will be documented in the appropriate Annex (reference section 2.2)

Christine N Kovich↗

Evolution of the NISAR Feed Antenna Design due to Environmental Requirements

NISAR (NASA ISRO SAR, National Aeronautics and Space Administration, Indian Space Research Organization, Synthetic Aperture Radar) is an Earth science project currently in its final development phases at NASA Jet Propulsion Laboratory (JPL) and at ISRO. Due for launch in 2023 it will assess how our planet changes over time by measuring differences in the Earth’s solid surface due to factors like climate change, movement and melting of glaciers, earthquakes, land-slides, deforestation, agriculture and others. The enabling instrument for this mission is a dual band radar (L-Band and S-Band) that feeds a 12m deployable mesh reflector. Given the extreme accuracy needed to perform these measurements from Low Earth Orbit (LEO) some of the most stringent requirements were pushed onto the antenna subsystem to control phase and gain stability over time. In this paper we describe how environmental requirements affected the antenna design and what techniques were used to meet these requirements.

Vacchione, Joseph D.↗

Requirements Engineering Scorecard and the Next-Generation Space Suit

The objective for a NASA contractor, the performing organization in this case study, is to provide engineering services to develop and deliver the next generation space suit to NASA, the customer in this case study. A case study with qualitative and quantitative analyses regarding a new process and approach to requirements engineering is described, with the intent that if utilized, these tools may have contributed to improvements across the project in terms of meeting cost, scope, budget and quality while appropriately accounting for risk management. The procedure entails a research method in which the current state of the project, current state of the art, and the identified systems engineering challenges are evaluated. Iterative models are tempered through development by continual improvements by engineering evaluation of engineers on the project. The current results have produced a prototype of a requirements engineering scorecard with implementations of FMEA and quantitative analysis to (i) identify root cause of underdeveloped requirements and (ii) project management impacts with regards to project risk. Forward work includes customer, performing organization, acceptance against applicable INCOSE community accepted practices.

INCOSE↗

Passivation of Spacecraft Pressure Vessels: Some Comments on Requirements, Principles, and Practices

Many space-faring organizations have requirements to limit the growth of orbital debris by passivating spacecraft that remain in orbit after mission end. These requirements state that a stored energy devices are to be fully depleted at the end of a spacecraft’s useful life. Spacecraft designs not able to comply with those requirements use a so-called “soft passivation” option. This report presents the results of two studies aimed at better understanding spacecraft pressure vessel passivation state-of-the-art. They summarize current practices and principles of pressure vessel passivation and present an approach that can be used to show that spacecraft propulsion system passivation has been achieved.

Spacecraft Passivation↗

Requirement Discovery Using Embedded Knowledge Graph With ChatGPT

The field of Advanced Air Mobility (AAM) is witnessing a transformation with innovations such as electric aircraft and increasingly automated airspace operations. Within AAM, the Urban Air Mobility (UAM) con-cept focuses on providing air-taxi services in densely populated urban areas. This research introduces the utilization of Large Language Models (LLMs), such as OpenAI's GPT-4, to enhance the UAM Requirement discovery process. This study explores two distinct approaches to leverage LLMs in the context of UAM Requirement discovery. The first approach evaluates the LLM's ability to provide responses without relying on additional outside systems, such as a relational or graph database. Instead, a vector store provides relevant information to the LLM based on the user’s question, a process known as Retrieval Augmented Generation (RAG). The second approach integrates the LLM with a graph database. The LLM acts as an intermediary between the user and the graph database, translating user questions into cypher queries for the database and database responses into human-readable answers for the user. Our team implemented and tested both solutions to analyze require-ments within a UAM dataset. This paper will talk about our approaches, implementations, and findings related to both approaches.

systems engineering↗

Tailoring of NASA-STD-3001 to Lunar Gateway Program Requirements

The Gateway Program must meet NASA's Agency-level human rating requirements, which are intended to accommodate human capabilities and limitations while protecting the safety of the crew, and providing to the maximum extent practical, the capability to safely recover the crew from hazardous situations. Human systems integration represents a key human rating component of Moon to Mars systems to support the execution of Artemis missions, including compliance with mandatory standards for Health and Medical, Safety and Mission Assurance, and Engineering. The human system requirements, together with the human systems integration plan, medical operations requirements, and Gateway sub-system specifications, represent the flow-down of NASA Health and Medical Standards (NASA-STD-3001, Volumes 1 and 2) into the Gateway system. This paper discusses how these documents and other human systems integration activities provide full consideration of human capabilities and limitations as part of the total system design trade space, serving as an example on how the human must be effectively integrated as part of the system in order to achieve mission success. At a bigger scale, the paper con-tributes to the application of systems engineering standards to cutting-edge space exploration initiatives and to the dialogue on how systems engineering can continue to evolve to meet the needs of such ambitious projects.

Systems engineering↗

Requirement Discovery Using Embedded Knowledge Graph with ChatGPT

The field of Advanced Air Mobility (AAM) is witnessing a transformation with innovations such as electric aircraft and increasingly automated airspace operations. Within AAM, the Urban Air Mobility (UAM) concept focuses on providing air-taxi services in densely populated urban areas. This research introduces the utilization of Large Language Models (LLMs), such as OpenAI's GPT-4, to enhance the UAM Requirement discovery process. This study explores two distinct approaches to leverage LLMs in the context of UAM Requirement discovery. The first approach evaluates the LLM's ability to provide responses without relying on additional outside systems, such as a relational or graph database. Instead, a vector store provides relevant information to the LLM based on the user’s question, a process known as Retrieval Augmented Generation (RAG). The second approach integrates the LLM with a graph database. The LLM acts as an intermediary between the user and the graph database, translating user questions into cypher queries for the database and database responses into human-readable answers for the user. Our team implemented and tested both solutions to analyze requirements within a UAM dataset. This paper will talk about our approaches, implementations, and findings related to both approaches.

systems engineering↗

Requirement Discovery Using Embedded Knowledge Graph With ChatGPT - Poster

The field of Advanced Air Mobility (AAM) is witnessing a transformation with innovations such as electric aircraft and increasingly automated airspace operations. Within AAM, the Urban Air Mobility (UAM) con-cept focuses on providing air-taxi services in densely populated urban areas. This research introduces the utilization of Large Language Models (LLMs), such as OpenAI's GPT-4, to enhance the UAM Requirement discovery process. This study explores two distinct approaches to leverage LLMs in the context of UAM Requirement discovery. The first approach evaluates the LLM's ability to provide responses without relying on additional outside systems, such as a relational or graph database. Instead, a vector store provides relevant information to the LLM based on the user’s question, a process known as Retrieval Augmented Generation (RAG). The second approach integrates the LLM with a graph database. The LLM acts as an intermediary between the user and the graph database, translating user questions into cypher queries for the database and database responses into human-readable answers for the user. Our team implemented and tested both solutions to analyze require-ments within a UAM dataset. This paper will talk about our approaches, implementations, and findings related to both approaches.

systems engineering↗

Clinical Trials at NASA: What Makes A Clinical Trial & What Are the Requirements for International Partners?

ClinicalTrials.gov is a public registry designed to fulfill ethical obligations by providing information about clinical research studies to the general public, patients, medical practitioners and the research community. In the United States, recent revisions to human subject’s regulations have prompted new criteria for what constitutes a clinical trial along with requirements not typically requested for other types of human subject’s research. Identification of investigational clinical trials is the shared responsibility of NASA, the IRB, and the scientific investigators designing and conducting the research. This talk aims to educate attendees on the history of the development of Clinicaltrials.gov, discussion of why these requirements are important to both participants and researchers, and information on how to identify clinical trials research. In addition, we will provide information on the different requirements for clinical trials conducted at NASA or aboard the International Space Station.

Clinicaltrials.gov↗

X-57 Static Structural Requirements and Airworthiness Approach

The National Aeronautics and Space Administration (NASA) Armstrong Flight Research Center (AFRC) (Edwards, California, U.S.A.) has been flying various types of aircraft, including experimental ones requiring structural modifications. Many of these aircraft aren’t typically certified by the Federal Aviation Administration (FAA) or the Department of Defense (DoD), but NASA can provide its own airworthiness certification utilizing a riskbased approach. The AFRC has established review processes and procedures to identify hazards, manage risks associated with flight programs, ensure safe flight operations, and satisfy programmatic requirements. The Aerostructures Branch at AFRC developed guidelines for the structural safety of flight, covering experimental aircraft, new components, payloads, and modifications. These guidelines detail structural design, analysis, instrumentation, ground testing, and flight-test operational aspects. The guidelines are followed for defining the airworthiness plan throughout the life cycle of a project. The guidelines can be tailored to the risk posture of each individual project. This paper documents the details of the structural airworthiness plan for the X-57 aircraft, including existing, modified, and newly developed structures. Additionally, it covers the design requirements and load cases specific to the X-57 aircraft.

Wesley W. Li↗

Space Launch System Block-1b USA Separation Analysis and Requirements Derivation From CLVTOPS Toolchain

Ensuring that rocket stage separation events provide positive clearance is critical to avoid loss of mission or crew. NASA's Marshall Space Flight Center (MSFC) has developed a cutting-edge toolchain to address this type of problem and it was used to set abstracted impulse requirements on, and to analyze the results of, the in-space separation event of the Universal Stage Adapter (USA) and the Exploration Upper Stage (EUS) of NASA's Space Launch System (SLS) Block-1B configuration. The toolchain is used as a hardware simulation to confirm positive body-to-body clearance during the separation event. It is also used to create a requirements-space simulation, which helps inform requirements as the hardware design matures.

Zachary T Muscha↗

SLS Block-1B USA Separation Analysis and Requirements Evaluation Using the CLVTOPS Toolchain

Ensuring that rocket stage separation events provide positive clearance is critical to avoid loss of mission or crew. NASA's Marshall Space Flight Center (MSFC) has developed a cutting-edge toolchain to address this type of problem and it was used to set abstracted impulse requirements on, and to analyze the results of, the in-space separation event of the Universal Stage Adapter (USA) and the Exploration Upper Stage (EUS) of NASA's Space Launch System (SLS) Block-1B configuration. The toolchain is used as a hardware simulation to confirm positive body-to-body clearance during the separation event. It is also used to create a requirements-space simulation, which helps inform requirements as the hardware design matures.

Zach Muscha↗

Nuclear Safeguards Infrastructure Required for the Next Generation Nuclear Plant (NGNP)

The Next Generation Nuclear Plant (NGNP) is a Very High Temperature Gas-Cooled Reactor (VHTR) to be constructed near Idaho Falls, Idaho The NGNP is intrinsically safer than current reactors and is planned for startup ca. 2021 Safety is more prominent in the minds of the Public and Governing Officials following the nuclear reactor meltdown accidents in Fukushima, Japan The authors propose that the NGNP should be designed with International (IAEA) Safeguards in mind to support export to Non-Nuclear-Weapons States There are two variants of the NGNP design; one using integral Prismatic-shaped fuel assemblies in a fixed core; and one using recirculating fuel balls (or Pebbles) The following presents the infrastructure required to safeguard the NGNP This infrastructure is required to safeguard the Prismatic and Pebble-fueled NGNP (and other HTGR/VHTR) The infrastructure is based on current Safeguards Requirements and Practices implemented by the International Atomic Energy Agency (IAEA) for similar reactors The authors of this presentation have worked for decades in the area of International Nuclear Safeguards and are recognized experts in this field Presentation for INMM conference in July 2012.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗

Advanced Nuclear Technology: Advanced Light Water Reactors Utility Requirements Document Small Modular Reactors Inclusion Summary

This report summarizes a project by EPRI to include requirements for small modular light water reactors (smLWR) into the EPRI Utility Requirements Document (URD) for Advanced Light Water Reactors. The project was jointly funded by EPRI and the U.S. Department of Energy (DOE). The report covers the scope and content of the URD, the process used to revise the URD to include smLWR requirements, a summary of the major changes to the URD to include smLWR, and how to use the URD as revised to achieve value on new plant projects.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗

Using Project Complexity Determinations to Establish Required Levels of Project Rigor

The concepts discussed in this paper 1) focus on using technical competencies and skills in making objective determinations regarding project complexity based on objective scoring criteria and 2) then using the complexity determinations to establish the level of rigor required in initiating, planning, executing, monitoring and controlling, and closing projects to maximize process efficiency. This paper presents a project complexity analysis methodology for defining the levels of project management process rigor a project team needs to employ to maximize project delivery efficiencies without compromising quality and performance. Methods for making project complexity determinations based on project lifecycle size, duration, organizational complexity, requirements, technology readiness, risk, and visibility are discussed. The paper correlates the levels of rigor needed by project management process groups given the determined level of project complexity. Next, the paper presents a graded approach to defining extent of team formation, planning documentation rigor, stakeholder communication rigor, requirements management rigor, acquisition planning, risk management, executing, and monitoring and controlling rigor dependent on project complexity determinations. Methods for integrating and aligning the project complexity determination methods into existing project management procedures and processes are also discussed as well as methods for training personnel in the use of the method and facilitating and monitoring effectiveness of implementation within an organization in which project delivery is a mission focus.

complexity, project, determination, management, tr↗

Energy Storage Requirements for Achieving 50% Penetration of Solar Photovoltaic Energy in California

We estimate the storage required to enable PV penetration up to 50% in California (with renewable penetration over 66%), and we quantify the complex relationships among storage, PV penetration, grid flexibility, and PV costs due to increased curtailment. We find that the storage needed depends strongly on the amount of other flexibility resources deployed. With very low-cost PV (three cents per kilowatt-hour) and a highly flexible electric power system, about 19 gigawatts of energy storage could enable 50% PV penetration with a marginal net PV levelized cost of energy (LCOE) comparable to the variable costs of future combined-cycle gas generators under carbon constraints. This system requires extensive use of flexible generation, transmission, demand response, and electrifying one quarter of the vehicle fleet in California with largely optimized charging. A less flexible system, or more expensive PV would require significantly greater amounts of storage. The amount of storage needed to support very large amounts of PV might fit within a least-cost framework driven by declining storage costs and reduced storage-duration needs due to high PV penetration.

14 SOLAR ENERGY↗