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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 973 records · Page 54
All sourcesNASA NTRSDOE OSTI
DOE OSTI2013

Improvement of Digital Filter for the FNAL Booster Transverse Dampers

Fermilab Booster has two transverse dampers which independently suppress beam instabilities in the horizontal and vertical planes. A suppression of the common mode signal is achieved by digital notch filter which is based on subtracting beam positions for two consecutive turns. Such system operates well if the orbit position changes sufficiently slow. Unfortunately it is not the case for FNAL Booster where the entire accelerating cycle consists of about 20000 turns, and successful transition crossing requires the orbit drifts up to about 10 μm/turn, resulting in excessive power, power amplifier saturation and loss of stability. To suppress this effect we suggest an improvement of the digital filter which can take into account fast orbit changes by using bunch positions of a few previous turns. To take into account the orbit change up toN-th order polynomial in time the system requires (N + 3) turns of “prehistory”. In the case of sufficiently small gain the damping rate and the optimal digital filter coefficients are obtained analytically. Numerical simulations verify analytical theory for the small gain and predict a system performance with gain increase.

43 PARTICLE ACCELERATORS↗
DOE OSTI2015

Vehicle Energy Management Optimization through Digital Maps and Connectivity

There is an opportunity for using digital maps with real-time updates to improve the energy management of vehicles. In this paper, we present research on how this can be achieved in the particular case of plug-in hybrid electric vehicles. With perfect knowledge of the trip ahead, it is possible to find the optimal control of the vehicle. Digital maps, however, provide only averaged information about the future itinerary, such as locations of stops, types of intersection, and average speeds. First, we demonstrate how we can generate naturalistic speed profiles for a given itinerary. We do so by augmenting the information from digital maps by actual recorded speeds from a travel survey and Markov chains. Second, we detail how these speed profiles can be used for control optimization. We use the Pontryagin minimum principle to optimally tune the vehicle energy management and then evaluate the actual fuel savings using the Autonomie simulation tool.

Connectivity↗
DOE OSTI2019

Development of a Fleet-Level Human Factors Engineering Program to Support the Digital Modernization of Multiple Turbine Control Systems

A number of years ago, Duke Energy and the United States (U.S.) Department of Energy (DOE) entered into a collaboration to support Duke’s digital upgrade activities for the main control rooms at three of their commercial nuclear power stations. The collaboration specifically focused on the human factors engineering (HFE) aspects of Duke’s plans to upgrade the legacy turbine control systems (TCS) at their Brunswick, Robinson, and Harris plants. This TSC upgrade involved installing a common digital control system (DCS), or distributed instrumentation and control (I&C) system platform, which multiple digital plant control systems can be integrated onto as the control rooms are modernized over time. Given the breadth and depth of the scope of this upgrade, DOE researchers at Idaho National Laboratory (INL) with expertise in human factors collaborated with Duke throughout the entire HFE life cycle to help ensure the upgrade was performed in a manner consistent with regulatory human factors review criteria, such as the U.S. Nuclear Regulatory Commission’s (NRC) Human Factors Engineering Program Review Model (NUREG 0711, 2012). This paper describes the HFE researchers performed through the early and middle phases of these TCS upgrades. Specific HFE activities include: 1) the development of a human factors program management plan, 2) performing an operational experience review, 3) evaluating the design human system interface while it was still in the early stages of development, and 4) developing a framework to help map these HFE activities to NUREG-0711 to help understand and catalog the value of different types and phases of human performance data collection. These four HFE activities are described in more detail below.

99 GENERAL AND MISCELLANEOUS↗
DOE OSTI2020

Randomization of dangling nodes in a digital circuit design to mitigate hardware trojans

Described herein are various technologies pertaining to randomizing logic associated with dangling nodes in a digital circuit design. A dangling node is an input to or output from a logic gate in the digital circuit design that is identified as not impacting a desired output of the digital circuit design. Randomizing the logic associated with a dangling node can include deleting a logic gate, adding a logic gate, replacing a logic gate with another logic gate, etc. Randomizing the logic associated with the dangling node prevents hardware trojans that may have been inserted into the circuit design from being implemented in a circuit that is generated based upon the design.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2021

Fractional delay filter for a digital signal processing system

A processing element for implementation in a digital signal processing system is provided. The processing element is configured to receive a first data stream comprising a plurality of digital values where each value represents a sample of an analog signal. The processing element is further configured to receive a second data stream comprising a series of digital values where each value represents a sample of the analog signal. The processing element is configured to filter the first data stream via a first Farrow-structured fractional delay (FD) filter and output a filtered first data stream; filter the second data stream via a second Farrow-structured FD filter and output a filtered second data stream; and temporarily store values from the second data stream and output the stored values to the first Farrow-structured FD filter so that the stored values can be used to filter the first data stream.

Stanley, Dennis L.↗
DOE OSTI2022

Modelica-json: Transforming energy models to digitize the control delivery process

Building simulation models are typically not used to generate the documentation required for bidding and project delivery of commercial building systems, or for their semantic modeling and commissioning. This paper presents a software tool that aids in digitizing the control delivery process, spanning simulation during design to implementation and formal verification during commissioning. The tool can generate from Modelica models digital documentation of control sequences. This digital documentation, along with other project drawings and specifications can be used for project bidding. It can also be used for implementation of control sequences through machineto-machine translation to commercial legacy control products, for which we are currently developing the proposed ASHRAE Standard 231P based on the presented work. Moreover, as-installed control sequences can be formally verified against the design specification, and a semantic model in Brick can be exported to aid in configuration of building analytics and fault detection. The paper presents what we believe is the first translation of a Modelica-implemented control sequence to a native implementation on a commercial control platform, using the webCTRL product line from Automated Logic. The paper also shows how a webCTRL implementation can be formally verified against its Modelica specification. These use cases have all been demonstrated with a prototype implementation that is now being further developed.

Wetter, Michael↗
DOE OSTI2022

Digitalization, Management and Synthesis of Thermal Hydraulic Legacy Data Using Dynamical System Scaling

A unique attribute of the nuclear industry is the extent by which designers, developers, operators, and regulators pay attention to demonstrating the safety case. The safety case for nuclear systems is a written, traceable expression of safety, demonstrating the system’s protective measures against uncontrolled radiological releases. The nuclear installation resiliency or safety takes overriding priority over function and performance. The preparation of the safety case heavily relies on extensive experimental campaigns that challenge the target design under a spectrum of postulated accident scenarios. For safety reasons, these experiments are typically conducted in sub-scale test apparatuses intended to reproduce the postulated accident scenarios and event sequences realistically but subject to proven similarity criteria, often referred to as scaling analyses. Since the dawn of the nuclear industry, significant resources have been committed to the construction and operation of such test facilities and a massive amount of data has been generated. Such test data have been and are still used to validate the fundamental assumptions of nuclear power plant phenomena. As we move into the digital world, capturing this multi-decades worth of information in a transparent, easily accessible, and usable manner for the public and industry stakeholders is of paramount importance. Over the last few years FPoliSolutions has been actively developing an enterprise digital data ontology platform (FPoliDON) intended to do just that. The concept was introduced in a paper at the previous NURETH edition and has been significantly enhanced since. With the vision of helping designers use the data to assess their safety case evaluation models, the platform was designed not only to ontologically organize the experimental data, but also to guide the user in the complex analytics associated with the interpretation and use of such test results. A new feature which has been recently added is the ability for the user to access a library of sophisticated mathematical procedures for performing scaling analyses. For this purpose, the Dynamical System Scaling (DSS) procedure invented by Dr. Jose’ Reyes was formulated as one of the services in the digital platform. These methods have been demonstrated to provide an excelled mathematical apparatus to identify similarity criteria or quantify distortions between measured data and the target prototypical conditions. Moreover, DSS can provide a level of synthesis across SETs and IETs which has the promise to yield efficiency in the evaluation code assessment activities. This is often a daunting and expensive task to set up evaluation models that support the safety case of current and future nuclear power plants.

Reyes, Jose↗
DOE OSTI2023

Discrete offset dithered waveform averaging for high-fidelity digitization of repetitive signals

Methods and devices for digitizing an analog repetitive signal using waveform averaging are described. An example method includes generating a discrete set of analog dither offset voltages, wherein at least two of the discrete set of analog dither offset voltages are different from each other, receiving the analog repetitive signal comprising multiple instances of a waveform, wherein the waveform has a waveform duration, generate a timing alignment to align each waveform of the analog repetitive signal and the corresponding analog dither offset voltage over the waveform duration, combining, based on the timing alignment, each waveform and the corresponding analog dither offset voltage over the waveform duration to produce an analog output signal, converting the analog output signal to a digital output signal, and producing, based on the timing alignment, a digital averaged signal based on averaging the multiple instances of the waveform in the analog output signal.

Buckley, Brandon Walter↗
DOE OSTI2023

Analyzing Hardware and Software Common Cause Failures in Digital Instrumentation and Control Systems using Dual Error Propagation Method

This paper develops a methodology for quantifying software common cause failures (CCFs) in digital instrumentation and control (I&C) systems of nuclear power plants. To support the transition of analog I&C systems to digital in nuclear power plants, probabilistic risk assessment (PRA) techniques are used. The hardware components of the I&C systems have reliability databases that can be used in the PRA studies. However, the failure data for redundant software components of the systems is sparse. Failure of components constitutes a CCF, wherein two or more components or systems fail due to a single shared cause and coupling mechanism. This paper proposes a quantification approach that can simultaneously model hardware and software components, incorporate the CCFs of software systems in the models, and bridge the gap between the failure quantification of models and the development of CCF parametric databases. We demonstrate the dual error propagation method (DEPM) by developing I&C systems failure models for a representative digital reactor trip system. The DEPM models are built to simulate the control and data flows within the systems and can accommodate failure states. By expanding DEPM to software CCFs, we generated alpha factor parameter estimates for each of the modeled error propagation mechanisms.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2023

Continuous dithered waveform averaging for high-fidelity digitization of repetitive signals

Methods and devices for digitizing an analog repetitive signal using waveform averaging are described. An example method includes generating a time-varying dither signal, receiving the analog repetitive signal comprising multiple instances of a waveform, wherein each waveform has a waveform duration, wherein an average of the time-varying dither signal over multiple waveform durations is substantially zero, and wherein the time-varying dither signal varies over each waveform duration, generating a timing alignment, combining each waveform with the corresponding portion of the time-varying dither signal over each waveform duration to produce an analog output signal, converting the analog output signal to a digital output signal, and producing, based on the timing alignment, a digital averaged signal based on averaging the multiple instances of the waveform in the analog output signal, wherein the timing alignment is used to align the multiple instances of the waveform in the analog output signal.

Buckley, Brandon Walter↗
DOE OSTI2015

Energy reconstruction in a highly granularity semi-digital hadronic calorimeter

A semi-digital hadronic calorimeter using Glass Resistive Plate Chambers (GRPCs) is one of the calorimeters candidates proposed for particle physics experiments at the future electrons collider. It is a high granular calorimeter which is required for application of the particle flow algorithm in order to improve the jet energy resolution as one of the goals of this experiments. We discussed the energy reconstruction, based on digital and semi-Digital methods, to study the effect on the improvement of the single particle energy resolution and the linearity of the detector response. This study was performed with the GEANT4 simulation. Results on the energy resolution and linearity, for negative pions over an energy range from 1 to 100 GeV are presented and compared with different energy reconstruction methods including Artificial Neural Networks. (authors)

43 PARTICLE ACCELERATORS↗
DOE OSTI2020

USACE FUSRAP Records Management Challenges in the Digital Age - 20242

In late 2016, the U.S. Army Corps of Engineers (USACE) implemented a Headquarters-supported nationwide records management initiative managed by the USACE-New England District to address the digitization and organization of Formerly Utilized Sites Remedial Action Program (FUSRAP) project files. This initiative will prepare USACE FUSRAP for moving toward a fully electronic system of records management. Additionally, the records management initiative streamlines the process and prepares the Administrative Record (AR) and Permanent Record (PR) file for transfer from USACE to the U.S. Department of Energy (DOE)-Office of Legacy Management (LM) following project closeout. Over the past couple of years, USACE and DOE-LM have been working to finalize a joint guidance document to assist in the FUSRAP records transition process. However, there remain key records management topics that require further discussion and development. Specifically, these topics include the implementation, process, and procedure for the capture of social media records and compliance with Section 508 of the Rehabilitation Act of 1973 (29 USC 794d), as amended. Due to advances in technology and the ease of communication it provides, USACE is using social media more often to interface with the public than 5, 10 or 15 years ago. The identification and capture of these records are challenging because it requires each USACE district or producer of a record to track what has been released through social media so that it can be captured as part of the AR or PR. USACE is currently evaluating processes and procedures for social media records capture. This paper explores how social media is being used by USACE across FUSRAP projects and best practices for the capture of social media records. Public accessibility to the project AR is required under the Comprehensive Environmental Response, Compensation, and Liability Act, which USACE FUSRAP must follow. As USACE FUSRAP ARs are converted to a digital format, greater accessibility to the files can be provided through web sites or other electronic media. However, Section 508 of the Rehabilitation Act must be considered when releasing electronic files to the public. Under Section 508, government agencies must ensure that information is made available to the public in a format that provides equal access to persons with disabilities. This paper discusses the electronic records requirements under Section 508 and addresses broad implementation of compliance across large digital records sets. Records management challenges are presented in the context of the FUSRAP records management program; however, these records management considerations and best practices are applicable across all Federal agency records management programs. Examples presented will further aid in understanding electronic records requirements that may be included on new USACE FUSRAP contracts as well as upcoming National Archives Records Administration requirements that will move us toward an electronic government. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2017

Spurious actuations in digital instrumentation and control systems - evaluation framework - 137

When a digital Instrumentation and Control (I and C) system or its associated components produce an unintended operation, it is known as a spurious actuation. Spurious actuations could lead to unnecessary challenges to safety equipment, challenge the ability of safety systems to provide their intended functions, or place the plant in an un-analyzed state. There is arguably a lack of clear and sufficient regulatory guidance for assessing spurious actuations. In an attempt to address this guidance gap, this paper provides a generic framework for evaluating spurious actuations in digital I and C systems, components, or supporting systems that are important to safety. The framework provides a methodology for: (1) defining the scope of the evaluation including supporting assumptions; (2) providing options for excluding a spurious actuation from the evaluation; (3) assessing the potential consequences from the assessed spurious actuations; and, (4) defining a high-level acceptance criteria. The methodology discussed by this paper is not to be construed as a requirement, regulation, or acceptable guidance by either domestic or international regulators; instead, it is intended to serve as a potential foundation or technical basis to be used for developing clear and sufficient regulatory guidance for assessing spurious actuations in digital I and C systems. (authors)

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2017

BWR modernization project: installation of a new digital feedwater control system - 295

A European BWR plant carried out a relevant and pioneering modernization project regarding the Feedwater and Feed Pump Turbine Control System, replacing the legacy analogic control with the new General Electric MarkVIe digital system. This digital instrumentation and control modernization, motivated by obsolescence, had a great impact on the main control room and on the plant operation. Tecnatom collaborated with the nuclear power plant in the project performing the following activities: early installation of the system in the full scope and classroom simulators, Human Factors Engineering (HFE) Verification and Validation (V and V), Simulation Assisted Engineering (SAE), design and implementation of cyber secure communication with the Plant Process Computer (PPC), operating procedures modification and plant operators training. Those activities contributed to the success of the project that was completed during the refueling outage as planned. Scheduling HFE verification before the design freeze allowed the plant to modify the Human Machine Interface (HMI) to comply with the standards and increase safety without overcharging the project. SAE resulted in the reduction of costs and time during the system commissioning through the detection of discrepancies and improvements in the control, covering different plant scenarios. All the activities carried out in the simulators before the implementation of the system in the plant contributed to validate it and to build confidence in the new control among the plant personnel. New digital system communication interfaces with the PPC saved cable laying works and allowed future expansions. (authors)

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2016

Common Cause Failure Mitigation Experience on Digital I and C System in NPP

CCF is failures of redundant or separate structures, systems, or components due to a shared root cause. The CCF includes those are resulted from severe environments, design errors, calibration and maintenance errors, and consequential failures. In addition, digital I and C systems can be vulnerable to CCF caused by software errors or software developed logic, which could defeat the redundancy achieved by the hardware architecture. Therefore, diversity and defense in-depth (D3) has become an important issue to overcome the CCF of the safety I and C system. The U.S. NRC has established regulatory guidance addressing a method for assessing D3 provided by the safety I and C system architecture at a NPP. This method enables determination of whether vulnerabilities to CCF have been adequately addressed. The guidance is included in BTP 7-19 and Chapter 7 of NUREG-0800. The regulatory guidance provides a methodology for designing diversity. APR1400 establishes the mitigating strategies that consider the characteristics of digital I and C system that contribute to the potential for CCF. The diversity strategies consist of a combination of diversity attributes and associated criteria to address potential CCF vulnerabilities in digital safety I and C system. (authors)

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2023

Full-Scale Soft-Sensor Implementations Enable WRRF Hybrid Digital-Twins

Digital twins (DTs) are on the rise in the wastewater treatment industry and, with ever-increasinguse of online data in more complex applications, it is bringing us towards a digital revolution withinwater resource recovery facilities (WRRFs). An integral data requirement is dynamic real-timeinfluent concentrations. However, few WRRFs have the ability to deploy sensors to generate therequired dynamic influent concentrations. This paper presents an innovative approach to generatedynamic influent profiles with a soft sensor primarily using bioreactor airflow rates and DT models.It has been implemented on three different full-scale facilities and demonstrate it is feasible toretrieve 15-minute interval diurnal influent concentrations. This study overcomes a key bottleneckin DT applications - the lack of realistic high-resolution influent profiles - fostering the developmentof DTs. The fact that the data used in this study are commonly available ensures wide applicabilityfor most WRRFs and prepares them for the advanced controls that digital twins can unlock.

Johnson, Bruce↗
DOE OSTI2024

Window-integrated charge-mode digital-to-analog converter for arbitrary waveform generator

A digital-to-analog converter circuit that creates an analog waveform from an input digital waveform. Operating the circuit comprises using the input digital waveform to 1) operate a charge control switch to set a charge time period, 2) operate a discharge control switch to set a discharge time period, 3) set a charge current magnitude using a charge gain, and 4) set a discharge current magnitude using a discharge gain. A charge source electrically charges a load capacitor during the charge time period (i.e., the charge mode). A discharge source electrically discharges the load capacitor during the discharge time period (i.e., the discharge mode). A circuit output transmits the analog waveform defined by the charge mode and the discharge mode. A charge current magnitude greater than the discharge current magnitude produces an upward-sloping analog waveform. A charge current magnitude less than the discharge current magnitude produces a downward-sloping analog waveform.

Li, Shaorui↗
DOE OSTI2025

Cybersecurity for Digital Energy Infrastructure : Trends, Threats, and Cyber-Informed Engineering

This presentation discusses the rise in digital energy infrastructure and associated threats. It covers an in-depth risk assessment of digital energy equipment and provides real world examples of threats, vulnerabilities, and known incidents. Research conducted by INL assessing and addressing these risks follows, concluding with a dive into Cyber-Informed Engineering (CIE) and it's application to digital energy infrastructure, using battery energy storage systems (BESS) as an example.

24 - POWER TRANSMISSION AND DISTRIBUTION↗