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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 289 records · Page 16
All sourcesNASA NTRSDOE OSTI
DOE OSTI2023

The Mycobacterium tuberculosis protein O -phosphorylation landscape

Bacterial phosphosignaling has long been synonymous with the histidine kinases of the two component systems (TCSs), but many bacteria, including Mycobacterium tuberculosis (Mtb), also code for Ser/Thr protein kinases (STPKs). STPKs are the main phosphosignaling enzymes in eukaryotes, but the full extent of phosphorylation on protein Ser/Thr and Tyr (O-phosphorylation) in bacteria is unclear. Here, we explored the global signaling capacity of the STPKs in Mtb. We generated a panel of STPK loss- and gain-of-function strains and measured the resulting O-phosphorylation and transcriptional changes. This deep phosphoproteome shows that O-phosphorylation in Mtb is a vastly underexplored protein modification that affects >70% of the proteome. The substrate-kinase interactions of STPKs show an extensive interface with the transcriptional machinery, resulting in STPK regulation of gene expression of over 30% of Mtb genes. Finally, Mtb O-phosphorylation gives rise to an expansive, distributed, and cooperative network of a complexity that has previously only been associated with eukaryotic phosphosignaling networks.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2025

Securing Smart Manufacturing: Detection of Cyber-Physical Attacks in CNC-Based Systems

As Industry 4.0 advances, the integration of computer numerical control (CNC) machines and advanced manufacturing technologies is transforming production into smart manufacturing systems that blend physical and digital processes as cyber-physical systems. However, this increased cyber-physical connectivity exposes manufacturing systems to cyber threats that can cause severe operational and financial disruptions. This paper presents a comparative study on cyber attacks and anomaly detection techniques in manufacturing, focusing on network traffic from CNC machines. The data extracted from network packets includes machine commands and control signals exchanged between the machine's interface and control system, crucial for maintaining operational integrity. We explore two types of cyber attacks, design modification and command injection, which pose substantial risks to CNC machine productivity and system integrity. Our investigation involves experiments on a real CNC system, highlighting the urgent need for effective detection mechanisms. To address these threats, we evaluate three anomaly detection methods: dynamic time warping (DTW), rolling average, and a deep learning, long short-term memory (LSTM) time-series-based autoencoder. Each is assessed for its effectiveness in identifying anomalous behaviors caused by the attacks. Our findings demonstrate the unique strengths and limitations of each detection technique, providing a deeper understanding of their applicability in realworld manufacturing environments. The comparative analysis indicates that while certain methods are highly effective against specific attack types, others offer broader applicability across different attacks. This study contributes to the accurate detection of anomalies in CNC machining processes, thereby enhancing the reliability and security of smart manufacturing systems against diverse cyber threats.

Williams, Bethanie [Tennessee Technological Univer↗
NASA NTRS1987

Improvements to the fastex flutter analysis computer code

Modifications to the FASTEX flutter analysis computer code (UDFASTEX) are described. The objectives were to increase the problem size capacity of FASTEX, reduce run times by modification of the modal interpolation procedure, and to add new user features. All modifications to the program are operable on the VAX 11/700 series computers under the VAX operating system. Interfaces were provided to aid in the inclusion of alternate aerodynamic and flutter eigenvalue calculations. Plots can be made of the flutter velocity, display and frequency data. A preliminary capability was also developed to plot contours of unsteady pressure amplitude and phase. The relevant equations of motion, modal interpolation procedures, and control system considerations are described and software developments are summarized. Additional information documenting input instructions, procedures, and details of the plate spline algorithm is found in the appendices.

Taylor, Ronald F.↗
NASA NTRS1993

Three-Dimensional Boundary-Layer program (BL3D) for swept subsonic or supersonic wings with application to laminar flow control

The theory, formulation, and solution of three-dimensional, compressible attached laminar flows, applied to swept wings in subsonic or supersonic flow are discussed. Several new features and modifications to an earlier general procedure described in NASA CR 4269, Jan. 1990 are incorporated. Details of interfacing the boundary-layer computation with solution of the inviscid Euler equations are discussed. A description of the computer program, complete with user's manual and example cases, is also included. Comparison of solutions with Navier-Stokes computations with or without boundary-layer suction is given. Output of solution profiles and derivatives required in boundary-layer stability analysis is provided.

Iyer, Venkit↗
NASA NTRS2002

Finite Element A Posteriori Error Estimation for Heat Conduction

This research investigates residual-based a posteriori error estimates for finite element approximations of heat conduction in single-layer and multi-layered materials. The finite element approximation, based upon hierarchical modelling combined with p-version finite elements, is described with specific application to a two-dimensional, steady state, heat-conduction problem. Element error indicators are determined by solving an element equation for the error with the element residual as a source, and a global error estimate in the energy norm is computed by collecting the element contributions. Numerical results of the performance of the error estimate are presented by comparisons to the actual error. Two methods are discussed and compared for approximating the element boundary flux. The equilibrated flux method provides more accurate results for estimating the error than the average flux method. The error estimation is applied to multi-layered materials with a modification to the equilibrated flux method to approximate the discontinuous flux along a boundary at the material interfaces. A directional error indicator is developed which distinguishes between the hierarchical modeling error and the finite element error. Numerical results are presented for single-layered materials which show that the directional indicators accurately determine which contribution to the total error dominates.

Lang, Christapher G.↗
NASA NTRS2008

Multifunctional Nanotube Polymer Nanocomposites for Aerospace Applications: Adhesion between SWCNT and Polymer Matrix

Multifunctional structural materials can enable a novel design space for advanced aerospace structures. A promising route to multifunctionality is the use of nanotubes possessing the desired combination of properties to enhance the characteristics of structural polymers. Recent nanotube-polymer nanocomposite studies have revealed that these materials have the potential to provide structural integrity as well as sensing and/or actuation capabilities. Judicious selection or modification of the polymer matrix to promote donor acceptor and/or dispersion interactions can improve adhesion at the interface between the nanotubes and the polymer matrix significantly. The effect of nanotube incorporation on the modulus and toughness of the polymer matrix will be presented. Very small loadings of single wall nanotubes in a polyimide matrix yield an effective sensor material that responds to strain, stress, pressure, and temperature. These materials also exhibit significant actuation in response to applied electric fields. The objective of this work is to demonstrate that physical properties of multifunctional material systems can be tailored for specific applications by controlling nanotube treatment (different types of nanotubes), concentration, and degree of alignment.

Park, Cheol↗
NASA NTRS2006

Implementation of Flow Tripping Capability in the USM3D Unstructured Flow Solver

A flow tripping capability is added to an established NASA tetrahedral unstructured parallel Navier-Stokes flow solver, USM3D. The capability is based on prescribing an appropriate profile of turbulence model variables to energize the boundary layer in a plane normal to a specified trip region on the body surface. We demonstrate this approach using the k-e two-equation turbulence model of USM3D. Modification to the solution procedure primarily consists of developing a data structure to identify all unstructured tetrahedral grid cells located in the plane normal to a specified surface trip region and computing a function based on the mean flow solution to specify the modified profile of the turbulence model variables. We leverage this data structure and also show an adjunct approach that is based on enforcing a laminar flow condition on the otherwise fully turbulent flow solution in user specified region. The latter approach is applied for the solutions obtained using other one- and two-equation turbulence models of USM3D. A key ingredient of the present capability is the use of a graphical user-interface tool PREDISC to define a trip region on the body surface in an existing grid. Verification of the present modifications is demonstrated on three cases, namely, a flat plate, the RAE2822 airfoil, and the DLR F6 wing-fuselage configuration.

Pandya, Mohagna J.↗
NASA NTRS2006

Implementation of Flow Tripping Capability in the USM3D Unstructured Flow Solver

A flow tripping capability is added to an established NASA tetrahedral unstructured parallel Navier-Stokes flow solver, USM3D. The capability is based on prescribing an appropriate profile of turbulence model variables to energize the boundary layer in a plane normal to a specified trip region on the body surface. We demonstrate this approach using the k-epsilon two-equation turbulence model of USM3D. Modification to the solution procedure primarily consists of developing a data structure to identify all unstructured tetrahedral grid cells located in the plane normal to a specified surface trip region and computing a function based on the mean flow solution to specify the modified profile of the turbulence model variables. We leverage this data structure and also show an adjunct approach that is based on enforcing a laminar flow condition on the otherwise fully turbulent flow solution in user-specified region. The latter approach is applied for the solutions obtained using other one-and two-equation turbulence models of USM3D. A key ingredient of the present capability is the use of a graphical user-interface tool PREDISC to define a trip region on the body surface in an existing grid. Verification of the present modifications is demonstrated on three cases, namely, a flat plate, the RAE2822 airfoil, and the DLR F6 wing-fuselage configuration.

Pandya, Mohagna J.↗
DOE OSTI2025

Evaluating FRI3D for Cost Savings in Fire Hazard Analysis at DOE Sites

A fire hazard analysis, required for many U.S. Department of Energy (DOE) facilities, is a complex, cumbersome, and costly process. Fire hazard analyses may be viewed as a checkbox, but ideally and in spirit with the DOE-STD-1066, the fire hazard analysis (FHA) should be a part of the workflow and used to help in modifications, maintenance, and improving operational safety. With current FHA development processes, it is both time and cost prohibitive for true integration. A tool called Fire Risk Investigation in 3D or FRI3D was developed under the DOE Light Water Reactor Sustainability program to simplify and automate many aspects of a fire probabilistic risk analysis for existing nuclear power plants. The FRI3D tool automates fire scenarios by combining approved fire simulation codes, U.S. Nuclear Regulatory Commission fire calculations methods, 3D modeling and visualization, and probabilistic risk analysis models into a single workflow supported with a user interface. FRI3D was initially designed for used in combination with a PRA, this case study, evaluated using FRI3D for a plant modification, determined the benefits that detailed fire modeling can have for U.S. Department of Energy facilities with or without a PRA model. It also looked at what tasks from DOE requirements could be reduced using the tool and what is needed to integrate fire hazard analysis into site workflow.

97 - MATHEMATICS AND COMPUTING↗
DOE OSTI2021

Solid State Ionics: Materials Development by Multiscale Modeling and Advanced Manufacturing Techniques

Solid-state ionic materials are an important enabling technology for energy conversion and storage. Solid-state batteries would be a safer and higher energy density alternative to commercially available lithium ion batteries (LIB), however their implementation requires ion conduction in solids at room temperature to occur on the same level as the current generation of liquid electrolytes. Microstructural modifications have been demonstrated to play a major role on ion transport through the control of grain boundary interfaces, which traditionally serve as “blocking” layers. Ultimately, these materials will be fabricated in thin films form as electrolytes in order to minimize ohmic losses in electrochemical devices. This work uses advanced manufacturing techniques in combination with theoretical modeling to implement a science-based approach in the deposition of thin films ion conductors with controlled microstructures used in ceramic energy conversion and storage devices.

25 ENERGY STORAGE↗
DOE OSTI2022

Upgrade of Gamma Spectrometry Systems for ORNL TRISO Fuel PIE

Gamma spectrometry is a key element in much of the post-irradiation examination (PIE) work performed under the Advanced Gas Reactor Fuel Development and Qualification (AGR) Program (Demkowicz et al. 2015; Stempien et al. 2021). Gamma spectrometers are integrated into three major capabilities used at the Oak Ridge National Laboratory (ORNL) Irradiated Fuels Examination Laboratory (IFEL) for PIE of tristructural-isotropic (TRISO) coated particles and fuel compacts: the Core Conduction Cooldown Test Facility (CCCTF), the Vertical Counting System (VCS), and the Irradiated Microsphere Gamma Analyzer (IMGA). The CCCTF includes liquid-nitrogen-cooled traps to extract 85 Kr out of the He sweep gas that passes through the furnace in which the fuel compacts are heated during safety testing. Analysis of the 85 Kr activity in the traps is the primary indicator for TRISO failure during safety testing. The VCS is a system used to accurately measure gamma emission from components placed in a lead-shielded chamber. It is used to count the CCCTF deposition cups after removal from furnace. Each cup resides in the CCCTF furnace for typically 12–24 h and is periodically replaced with a fresh cup throughout the safety test. Metallic fission products collect on the water-cooled cups and several gamma-emitting isotopes ( 110 mAg, 134 Cs, 137 Cs, 154 Eu, and 155 Eu) are often measured and provide indication of the retention performance of the TRISO coatings. The VCS is also used to measure the presence of these isotopes on the CCCTF tantalum liner and sweep gas inlet tube for the determination of cup collection efficiency, as well as support other gamma spectrometry needs related to calibration of the 85 Kr fission gas traps and various other special PIE tasks. The IMGA uses gamma spectrometry to measure the inventory of gamma-emitting isotopes in individual TRISO particles. An automated particle handling system within the IMGA hot cell removes each particle from a source vial and positions it in front of a gamma detector, and output from the gamma spectrometer is used by the IMGA software to determine a destination vial such that particles are sorted according to their inventory and retention characteristics. At the conclusion of the AGR-1 and AGR-2 PIE campaigns, the gamma spectrometer systems used at ORNL to support that PIE had reached the end of its life cycle due to gradual obsolescence of the hardware and software. Upgrade of the Canberra Genie 2000 software used by these systems to a Windows 10 version was not a viable option, because the newest Windows 10 version offered by Mirion (the new owner of the Canberra technology) did not include the dynamic-link libraries (DLLs) needed for integration with the custom PIE software used with the CCCTF and IMGA, and Mirion had no current plans for development and release of Windows 10 versions of these DLLs with the Model S560 Genie 2000 Programming Library. Ultimately a switch was made to ORTEC gamma spectrometry systems, which appeared to be a more sustainable solution due to more proactive vendor support. The ORTEC conversion involved replacing the aging detector preamplifier and multichannel analyzer (MCA) hardware, upgrading the obsolete Windows 7 computers to Windows 10 compatible models, adopting ORTEC GammaVision software, and extensive modification of the ORNL-developed Visual Basic .NET (VB.NET) programs that provide the CCCTF and IMGA user interfaces.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
NASA NTRS1990

Concurrent Image Processing Executive (CIPE). Volume 1: Design overview

The design and implementation of a Concurrent Image Processing Executive (CIPE), which is intended to become the support system software for a prototype high performance science analysis workstation are described. The target machine for this software is a JPL/Caltech Mark 3fp Hypercube hosted by either a MASSCOMP 5600 or a Sun-3, Sun-4 workstation; however, the design will accommodate other concurrent machines of similar architecture, i.e., local memory, multiple-instruction-multiple-data (MIMD) machines. The CIPE system provides both a multimode user interface and an applications programmer interface, and has been designed around four loosely coupled modules: user interface, host-resident executive, hypercube-resident executive, and application functions. The loose coupling between modules allows modification of a particular module without significantly affecting the other modules in the system. In order to enhance hypercube memory utilization and to allow expansion of image processing capabilities, a specialized program management method, incremental loading, was devised. To minimize data transfer between host and hypercube, a data management method which distributes, redistributes, and tracks data set information was implemented. The data management also allows data sharing among application programs. The CIPE software architecture provides a flexible environment for scientific analysis of complex remote sensing image data, such as planetary data and imaging spectrometry, utilizing state-of-the-art concurrent computation capabilities.

Lee, Meemong↗
NASA NTRS1998

HPCC Methodologies for Structural Design and Analysis on Parallel and Distributed Computing Platforms

In this grant, we have proposed a three-year research effort focused on developing High Performance Computation and Communication (HPCC) methodologies for structural analysis on parallel processors and clusters of workstations, with emphasis on reducing the structural design cycle time. Besides consolidating and further improving the FETI solver technology to address plate and shell structures, we have proposed to tackle the following design related issues: (a) parallel coupling and assembly of independently designed and analyzed three-dimensional substructures with non-matching interfaces, (b) fast and smart parallel re-analysis of a given structure after it has undergone design modifications, (c) parallel evaluation of sensitivity operators (derivatives) for design optimization, and (d) fast parallel analysis of mildly nonlinear structures. While our proposal was accepted, support was provided only for one year.

Farhat, Charbel↗
NASA NTRS2001

Use of Human Modeling Simulation Software in the Task Analysis of the Environmental Control and Life Support System Component Installation Procedures

Virtual reality and simulation applications are becoming widespread in human task analysis. These programs have many benefits for the Human Factors Engineering field. Not only do creating and using virtual environments for human engineering analyses save money and time, this approach also promotes user experimentation and provides increased quality of analyses. This paper explains the human engineering task analysis performed on the Environmental Control and Life Support System (ECLSS) space station rack and its Distillation Assembly (DA) subsystem using EAI's human modeling simulation software, Jack. When installed on the International Space Station (ISS), ECLSS will provide the life and environment support needed to adequately sustain crew life. The DA is an Orbital Replaceable Unit (ORU) that provides means of wastewater (primarily urine from flight crew and experimental animals) reclamation. Jack was used to create a model of the weightless environment of the ISS Node 3, where the ECLSS is housed. Computer aided drawings of the ECLSS rack and DA system were also brought into the environment. Anthropometric models of a 95th percentile male and 5th percentile female were used to examine the human interfaces encountered during various ECLSS and DA tasks. The results of the task analyses were used in suggesting modifications to hardware and crew task procedures to improve accessibility, conserve crew time, and add convenience for the crew. This paper will address some of those suggested modifications and the method of presenting final analyses for requirements verification.

Estes, Samantha↗
NASA NTRS1972

Inventory of forest and rangeland and detection of forest stress

The author has identified the following significant results. Seventy-two ground sensors were interfaced with three DCP'S at the Black Hills test site. Unfortunately, the transmitters had to be returned for modification and forestry sensed data is not available. The DCP's did operate properly from the Berkeley laboratory and data were recovered from the Goldstone and Alaska stations via Goddard. Replicated training sets and test sets have been selected from all three test site areas in preparation for the receipt of ERTS imagery and digital tapes. From 600 and 800 points have been selected at each site location and UTM coordinates determined. Templates are being made of these sets. As of September 1, ERTS-generated data had not been received and no statements can be made regarding quality or suitability for forest and range experiments. Aerial photography (scale 1:32,000) of the Manitou (226 C) and Black Hills (226 A) sites was taken with CIR in June. Various scales (1:2,000; 1:10,000; 1:20,000; and 1:40,000) of 70 mm photographs were obtained at Manitou with normal color, CIR, and panchromatic in August.

Heller, R. C.↗
NASA NTRS1976

Artwork Interactive Design System (AIDS) program description

An artwork interactive design system is described which provides the microelectronic circuit designer/engineer a tool to perform circuit design, automatic layout modification, standard cell design, and artwork verification at a graphics computer terminal using a graphics tablet at the designer/computer interface.

Johnson, B. T.↗
NASA NTRS1992

Ultrasonic Detection Of Transverse Cracks In Composites

Conventional ultrasonic C scan used to detect flaws in graphite/epoxy composite panels modified to enhance sensitivity to transverse cracks. Modification involves reorientation and repositioning of ultrasonic transmitter and receiver to take advantage of mode-conversion phenomena at interfaces between liquid couplant and panel to be probed. Angle of incidence chosen so only shear waves propagate obliquely through panel. Although mode-conversion equations solved to take full advantage of technique somewhat complicated, they are straightforward, and technique implemented easily in practice.

Pereira, J. Michael↗
NASA NTRS1997

Proposal for beta-test of GIFCORCODE

This year's effort produced very significant progress in the development of the software package heretofore known as GIFCORCODE. One important change has been in the name. The package is now named CONDUIT for CONtrol Designer's Unified InTerface. There have also been some more significant changes in the way CONDUIT is used. These changes caused some modifications in the work accomplished. Both the original goals for the year and the modifications will be described in the next section of this report. The major goal for this year was to bring CONDUIT to beta-test. This has been accomplished. The software package is in beta-test at Bell Helicopters and has been since September 1996. This and the other achievements during the past year are described in the third section of this report. Some discussion of the scaling issue is also included here. This is in answer to a question that arose at one of the CONDUIT briefings. The report concludes with a brief set of suggestions for further work. An appendix describing the issues involved in dynamic linking is also included.

Levine, William S.↗