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At least 1,189 records · Page 66

Change detection and change monitoring of natural and man-made features in multispectral and hyperspectral satellite imagery

An approach for land cover classification, seasonal and yearly change detection and monitoring, and identification of changes in man-made features may use a clustering of sparse approximations (CoSA) on sparse representations in learned dictionaries. A Hebbian learning rule may be used to build multispectral or hyperspectral, multiresolution dictionaries that are adapted to regional satellite image data. Sparse image representations of pixel patches over the learned dictionaries may be used to perform unsupervised k-means clustering into land cover categories. The clustering process behaves as a classifier in detecting real variability. This approach may combine spectral and spatial textural characteristics to detect geologic, vegetative, hydrologic, and man-made features, as well as changes in these features over time.

47 OTHER INSTRUMENTATION↗

Numerical modeling of heterogeneous asperity distributions controlling the growth of shear rupture on a frictional fault

Copyright 2016 ARMA, American Rock Mechanics Association. A better understanding of the strength distributions and the seismic response of asperities failing within a cohesive (or breakdown) region of the growing shear rupture is important in many engineering disciplines, such as, hydraulic fracture and induced seismicity. In the laboratory, a fault is experimentally modeled by a 400 mm × 80 mm × 12 mm PMMA slider sheared across a large PMMA base plate. A pressure-sensitive film was employed to localize and size, and measure normal stress upon contact junctions. Moments prior to rapid sliding, multiple discrete and localized dynamic events (or foreshocks) were observed at a section of the fault that exhibited a sparse to dense transition in asperity distribution. Experiments showed that foreshocks occurred as the crack (rupture front) moved into the resistive patch of densely distributed asperities. We use the results of pressure sensitive film asperity measurements to develop a heterogeneous finite element (FE) model that studies the effect of asperities within the cohesive region have on the expanding shear crack. Slip accumulated heterogeneously during the loading cycle due to the non-uniform distribution of asperities. We study the constitutive behavior of a frictional interface where local slip is determined by the asperities and their ability to communicate elastically. A foreshock (Mw -7.4) was simulated in a quasi-static manner by instantaneoulsy removing an asperity contact during the loading cycle. The foreshock increased shear stress perturbations to neighboring regions up to distances of ~ 10 to 15 source radii.

Selvadurai, PA↗

Wireless Interrogation of a High Temperature Antenna Sensor Without Electronics

This paper presents a novel interrogation mechanism for an antenna sensor subjected to high temperatures. In sensor node, an Ultra-wide Band (UWB) microstrip antenna was used as a wireless Tx/Rx transceiver to amplify the reflected interrogation signal from the temperature-sensing element, i.e. the patch antenna-sensor. A microstrip delay line was used to connect the Tx/Rx antenna and the antenna-sensor so that the reflected signal from the sensor node is delayed and can be separated from the background clutter using time-domain (T-D) gating technique. In this paper, the principle of operation of the proposed interrogation mechanism is first discussed, followed by the design and simulations of the sensor node circuitry. Finally, a temperature test was conducted to validate the wireless temperature sensing performance of the antenna sensor.

Tchafa, Franck Mbanya↗

An End-to-end Deep Convolutional Neural Network for a Multi-scale Image Matching and Localization Problem

Abstract Diverse imaging techniques are utilized in many scientific domains to acquire a rich description of the subject under study and to further discover a variety of its proper- ties. Especially, in sample systems, by probing with optical, electron or x-ray beams, the captured images describe the sample in an extremely large range of length scales. This makes the correlation from one image to another very difficult in addition to the intrinsic appearance complexity of those scientific images. In this paper, we aim to tackle this multi-scale image matching and localization problem by proposing an end-to-end deep convolutional neural net- work. Our proposed network is designed to first generate different filters according to the two queried images originated from different length scales. Then, to compute the correlation map, we use these filters to predict the correspondence between the two images. For the training and evaluation, we collect a number of electron microscopy experiments to form a multi-scaled image patch dataset comprised of various material structures. We observe about 90% accuracy for multi-scale image matching and localization while a triplet-based network shows about 78% accuracy.

97 MATHEMATICS AND COMPUTING↗

Fairchilde Puppet Environment

The software creates a minimal directory organization structure and data isolation methods so that groups and projects are differentiated and isolated by levels in the hierarchy naming schemes. It also allows various versions of Puppet server and client to be used by different groups and projects so that groups can maintain their own upgrade and patching schedules without introducing breaking changes and unnecessary service outages to other groups using the framework.

Campfield, Michael P↗

Non-contact optical system for detecting ultrasound waves from a surface

A system for detecting pressure, acoustic or ultrasound waves within an entity having a surface including the steps of attaching a signal converting material to the surface. The waves are generated by direct ejection from the surface, generation via energy deposition on the surface, generated spontaneously or, generated by directing light energy to the light absorbing target. The absorbing target subsequently generates acoustic pressure waves. The acoustic waves propagate to the surface of the entity and the signal converting material, wherein the acoustic pressure waves create vibrations in the signal converting material; and detecting the waves in the signal converting material with an optical detection system. Information about the absorbing target is obtained by the absorbing target reflecting the waves. The signal converting material can be a gel-like material containing optical elements, a multi-layer patch, or other material.

Demos, Stavros G.↗

Software-Defined Networking Traffic Engineering Process for Operational Technology Networks

Network design goals are often functional with little consideration for security. Growth and maintenance of critical infrastructure mission-focused networks can be ad hoc and preclude large-scale technology replacements, reconfigurations, or even patching. These restrictions are contributing factors to increased vulnerabilities. Over 90% of all attacks begin with phishing and include lateral movement (Frinke 2019). Adopting a software-defined networking (SDN) approach is an effective mitigation strategy for many existing vulnerabilities. SDNs deny-by-default approach to networking restricts an adversary’s freedom of movement without impacting an organization’s mission. SDN implementations require a process that identifies an organization’s mission-specific network communications. A well-defined traffic engineering process ensures that only known devices communicate with each other on specific ports.

Software Defined Networking, Situational Awareness↗

Cathodoluminescence-based nanoscopic thermometry in a lanthanide-doped phosphor

Crucial to analyze phenomena as varied as plasmonic hot spots and the spread of cancer in living tissue, nanoscale thermometry is challenging: probes are usually larger than the sample under study, and contact techniques may alter the sample temperature itself. Many photostable nanomaterials whose luminescence is temperature-dependent, such as lanthanide-doped phosphors, have been shown to be good non-contact thermometric sensors when optically excited. Using such nanomaterials, in this work we accomplished the key milestone of enabling far-field thermometry with a spatial resolution that is not diffraction-limited at readout. We explore thermal effects on the cathodoluminescence of lanthanide-doped NaYF$_4$ nanoparticles. Whereas cathodoluminescence from such lanthanide-doped nanomaterials has been previously observed, here we use quantitative features of such emission for the first time towards an application beyond localization. We demonstrate a thermometry scheme that is based on cathodoluminescence lifetime changes as a function of temperature that achieves $\sim$ 30 mK sensitivity in sub-$\mu$m nanoparticle patches. The scheme is robust against spurious effects related to electron beam radiation damage and optical alignment fluctuations. We foresee the potential of single nanoparticles, of sheets of nanoparticles, and also of thin films of lanthanide-doped NaYF$_4$ to yield temperature information via cathodoluminescence changes when in the vicinity of a sample of interest; the phosphor may even protect the sample from direct contact to damaging electron beam radiation. Cathodoluminescence-based thermometry is thus a valuable novel tool towards temperature monitoring at the nanoscale, with broad applications including heat dissipation in miniaturized electronics and biological diagnostics.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

Maximizing the habitat restoration potential of controlled releases at hydropower dams; Understanding impacts of hydrograph form on sediment transport

Regulation of streamflow for hydropower often alters natural hydrographs, commonly reducing peak flows, increasing baseflows, and increasing ramping rates. Simultaneously, reservoirs typically trap sediment, reducing the supply to the reach downstream of the dam. These changes to the flow regime and sediment supply impact channel morphology and sediment transport processes in ways that reduce the diversity and suitability of instream habitat. A variety of restoration approaches have attempted to mitigate for some of these changes and a growing number include releases of high flows designed to mimic key characteristics of the pre-regulation hydrograph. One example is the Trinity River, CA, where the addition of augmentation gravel to the channel has been combined with high flows designed to restore portions of the pre-regulation hydrograph to improve channel conditions for spawning fish on the Trinity River, CA. Another example is the high-flow experiments on the Colorado River through the Grand Canyon that aim to restore eroding sand bars that not only provide habitat but camping for rafting groups. More projects that restore portions of the pre-regulation hydrograph are likely in the future because the Federal Energy Regulatory Commission (FERC) requires habitat mitigation efforts in the relicensing process for hydropower facilities. However, the outcomes of these costly restoration efforts are often hard to predict because little is known about how hydrograph form actually impacts channel morphology and bedload transport in rivers. Here we summarize the results of two flume experiments designed to investigate the impacts of hydrograph form on the morphology of a channel bar and bedload transport processes. The first experiment primarily investigated the impacts of hydrograph recession rate on the morphology of a channel-bar in a sand bed channel. Additional runs examined the combined effects of hydrograph recession and a dense patch of vegetation on bar form. The second flume experiment investigated bedload transport processes in an armored, gravel bed channel during hydrographs with varying form. It documented total bedload flux for a hydrograph, bedload flux rates, persistence of the coarse armor surface, and changes in bed surface structure. Both experiments observed links between hydrograph form and the resulting bar morphology or bedload transport processes, providing insight into ways that high flow hydrographs can be designed to better facilitate restoration goals downstream of hydropower facilities.

13 HYDRO ENERGY↗

Mapping Lake Sturgeon ( Acipenser Fluvescens ) Spawning habitat in the Upper Tennessee River Using Side Scan Sonar

The Lake Sturgeon Acipenser fulvescens is a fish species that was once dispersed widely throughout the Mississippi River drainage but was largely extirpated from the southern portions of its range by overfishing and habitat degradation. There is an ongoing restoration effort to reestablish the Lake Sturgeon to rivers of the Southeastern United States. Reintroduced juvenile Lake Sturgeon now occupy several reservoirs along the Upper Tennessee River that are separated from each other by hydroelectric dams. To complete their life history, Lake Sturgeon will migrate upriver from reservoir habitats to more lotic habitats and spawn over coarse rocky substrate, even in the tailwaters of impassable dams. We mapped the substrate of four tailwaters that may be future Lake Sturgeon spawning locations using low-cost, consumer-grade side scan sonar and a GIS. We used video imagery collected from random locations within the mapped areas to validate our digitization of sonar imagery. We calculated the area of four substrate classes displayed in the maps to assess the suitability of each of the tailwaters for Lake Sturgeon spawning. The best spawning substrate (unembedded, coarse, rocky substrate 6 – 25 cm in diameter) comprised 17.0 – 30.5% of the total area mapped at each dam, while the least suitable substrate class (fine sediment <0.2 cm in diameter) comprised 6.2 – 30.7% of the mapped areas. Our results suggest any future spawning events by Lake Sturgeon below each of these dams are likely to encounter some suitable spawning substrate patches, while management opportunities exist to supplement other tailwater areas with suitable spawning substrate.

13 HYDRO ENERGY↗

Complementary workflows for identifying one-hop network behavior and multi-hop network dependencies

A network analysis tool evaluates network flow information in complementary workflows to identify one-hop behavior of network assets and also identify multi-hop dependencies between network assets. In one workflow (e.g., using association rule learning), the network analysis tool can identify significant one-hop communication patterns to and/or from network assets, taken individually. Based on the identified one-hop behavior, the network analysis tool can discover patterns of similar communication among different network assets, which can inform decisions about deploying patch sets, mitigating damage, configuring a system, or detecting anomalous behavior. In a different workflow (e.g., using deep learning or cross-correlation analysis), the network analysis tool can identify significant multi-hop communication patterns that involve network assets in combination. Based on the identified multi-hop dependencies, the network analysis tool can discover functional relationships between network assets, which can inform decisions about configuring a system, managing critical network assets, or protecting critical network assets.

97 MATHEMATICS AND COMPUTING↗

Growth and Properties of Vapor Diffused Nb3Sn Coating for Superconducting Radiofrequency Accelerator Cavity Applications

The desire to reduce construction and operating costs of future SRF accelerators motivates the search for higher-performing alternative materials. Nb3Sn (Tc ~ 18.3 K and Hsh ~ 425 mT) is the front runner. The tin vapor diffusion process is currently the technique of choice to produce promising Nb3Sn-coated cavities. Understanding Nb3Sn nucleation and growth in this process is essential to progress. Samples representing different stages of Nb3Sn formation have been produced and studied to elucidate the effects of nucleation, growth, process conditions, and impurities. Nb3Sn films with thickness from a few hundred nm up to ~15 µm were grown and characterized. The microscopic examination of samples suggests the mechanisms of thin film nucleation and growth. Broadly, nucleation deposits tin as a thin surface phase and, under some conditions, a few hundred nanometer sized particles as well. Conditions that impair nucleation promote the formation of defects, such as ?patches?, in subsequent coating growth. Analysis of coated samples is consistent with the model of Nb3Sn grown in which tin diffuses via grain boundaries to Nb3Sn-Nb interface, where the growth Nb3Sn into the niobium bulk takes place. Similar scaling laws are found for grain growth and layer thickness. Non-parabolic layer growth is consistent with significant grain growth, which reduces the number of Sn-transport channels. Examination of patchy region in Nb3Sn coating revealed it to be large single crystalline grains, pointing to impeded Nb3Sn layer growth due to low grain boundary density, resulting in a significantly thin coating in those areas. Examination of RF loss regions from a coated cavity, identified with a thermometry mapping system showed patchy regions and carbonus defects were associated with strong local field-dependent surface resistance. RF measurements of coated cavities were combined with material characterization of witness samples and coated-cavity cutouts to improve the coating process. Understanding obtained and applied to cavity coatings, resulted in single-cell Nb3Sn cavities with a quality factor of ~2 ×1010 up to 15 MV/m accelerating gradient at 4 K, without "Wuppertal" Q-slope. We have also produced Nb3Sn-coated CEBAF 5-cell cavities with accelerating gradients useful for accelerator cryomodules. This dissertation will discuss the genesis of the Nb3Sn coating in a typical tin vapor diffusion process, effects of different process parameters, and its consequences to the coating of single-cell and multi-cell SRF cavities.

Pudasaini, Uttar↗

Shared aperture antenna array

A shared aperture antenna array including an array of antennas is disclosed. Elements of neighboring antennas are shared to create additional antennas. The shared elements include radiating patches and apertures. Each antenna shares an aperture with neighboring antennas. The array of antennas may be linear or two-dimensional. A phase shifting network with single-pole-single-throw reflective switches may be coupled to the antennas.

Tedeschi, Jeffrey R.↗

FY 2021 High Performance Computing Overall Systems Availability

INL HPC capabilities were utilized by individuals at universities, industry, and government laboratories for a wide range of research and engineering activities between October 1, 2020 and September 30, 2021. The HPC systems themselves experienced minimal downtime over the course of the fiscal year. Most downtime was planned to apply critical security patches to system software. The most serious of the unplanned downtime events occurred due to maintenance on the Kohler backup generator in July. Users were kept notified of all events, both planned and unplanned, via 36 total email notifications in FY-21. The INL HPC systems continue to provide high availability for collaboration and innovation in nuclear energy systems research.

99 GENERAL AND MISCELLANEOUS↗

Microwave diagnostics and passive sensors for pipeline, well-bore, and boiler-tube monitoring

Materials, methods of making, and methods of using an integrated wireless detector for real time interrogating metallic tubular structures comprising: an RF patch antenna; a passive surface acoustic wave (SAW) sensor; and data analytic methodologies. An embodiment relates to interrogating a metallic structure having a uniform cross section using an antenna which launches electromagnetic radiation. A sensor may be located within the structure is configured to re-emit electromagnetic radiation modified depending on parameters for which the sensor has been functionalized. An antenna may receive radiation as modified by the sensor, or may receive the transmitted or backscattered radiation directly, without use of a sensor. The antenna then communicates wirelessly with an interrogator providing data which may be used to understand the operational status of the structure in real-time.

Ohodnicki, Paul R.↗

Performance Evaluation of Distributed Energy Resource Management Algorithm in Large Distribution Networks

This paper presents performance evaluation of hierarchical optimization and control for distributed energy resource management system (DERMS) in large distribution networks via an advanced hardware-in-the-loop (HIL) platform. The HIL platform provides realistic testing in a laboratory envi-ronment, including the accurate modeling of a full-scale dis-tribution system of 11,000 nodes, the DERMS software con-troller, and 90 power hardware photovoltaics (PVs) and bat-tery inverters. The applied DERMS algorithm is designed based on a real-time optimal power flow algorithm and im-plemented with acceleration design that performs fast dis-patch of simulated PVs and real physical hardware DER devices every 4 seconds.

distributed energy management system (DERMS)↗

Development of an end state vision to implement digital monitoring in nuclear plants

Transitioning from an onsite Maintenance & Diagnostics Center to cloud-based services offers many new opportunities with computing power and storage, but also new challenges in terms of networking and security. This report will cover everything required for that transition including data processing and uploading to cloud services, feature selection, model creation, and result visualization for decision making. Although there are several other cloud-based services (e.g. Amazon Web Services and Google Cloud), this report explores Microsoft Azure to simplify nomenclature and maintain a consistent focus. Many of the services offered by Microsoft Azure are also available in the other cloud-based services, and their differences have been recorded in other literature. The Azure services most important to a nuclear power plant including networking & security, storage & databases, and Artificial Intelligence (AI) are reviewed here. Networking covers all aspects related to communication to Azure resources including security, privacy, and redundancy. Storage & databases includes data storage, upgrading, patching, backups, and monitoring. The AI services allows the user access to the machine learning (ML) techniques developed with Azure including automated ML, anomaly detection, computer vision, and natural language processing. This report summaries the features, capabilities, and challenges when using cloud-based services in a user-friendly manner.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Snowmass2021: Opportunities from Cross-survey Analyses of Static Probes

Cosmological data in the next decade will be characterized by high-precision, multi-wavelength measurements of thousands of square degrees of the same patches of sky. By performing multi-survey analyses that harness the correlated nature of these datasets, we will gain access to new science, and increase the precision and robustness of science being pursued by each individual survey. However, effective application of such analyses requires a qualitatively new level of investment in cross-survey infrastructure, including simulations, associated modeling, coordination of data sharing, and survey strategy. The scientific gains from this new level of investment are multiplicative, as the benefits can be reaped by even present-day instruments, and can be applied to new instruments as they come online.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗