SEARCH · Engineering Papers

Results for “software differences”

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.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,675 records · Page 93

All sources NASA NTRS DOE OSTI

DOE OSTI2020

Status Report on IES Plug-and-Play Framework

This report discusses the status of the flexible plug-and-play framework development currently ongoing that aims to integrate Modelica/Dymola with the Risk Analysis and Virtual ENviroment (RAVEN) software in terms of both Functional Mock-Up Interface (FMI)/Functional Mock-Up Unit (FMU) construction and repository structures that aim to ease the sharing and simulation of complex dynamic models. This report provides discusses the FMI/FMU adaptors that have been created within the HYBRID repository to allow users to quickly export models as FMUs. Several examples are shown that highlight the step-by-step process of converting an existing Modelica model into an FMU for use within the Dymola platform. Simulation results demonstrate that, while minor differences may occur, the overall control, trends, and solution integrity is maintained between standard Modelica simulation and FMU simulation results. However, it is worth noting that, for small systems, the FMU results have a slower simulation time than the Modelica only simulation. Using this process, a company can provide models that contain proprietary information to entities without disclosing any of the information about the model that could be considered business sensitive. Such an ability would allow institutions to bypass the necessity of “whitewashing” data. In addition to the investigative work being conducted on FMUs and FMIs, a series of updates to the hybrid repository has been completed. These updates include the addition of Modelica system-level regression tests and software quality assurance documentation that ensure that modifications to the Modelica models do not alter system-level model results. Overall, extensive work has been completed on developing FMUs and FMIs from existing models, understanding the requirements and limitations of FMUs, and opensourcing the HYBRID repository with an integrated regression system.

99 GENERAL AND MISCELLANEOUS↗

DOE OSTI2022

NIRP Core Software Suite v.5.1

SAND2023-06610O The Nuclear Incident Response Program (NIRP) Core Software Suite is a set of code that supports multiple applications. It includes miscellaneous base code for data objects, mathematic equations, and user interface components that are used for developing large applications, including those used for data management. Among the types of applications: • Analyst Manager is used for managing contact information, which is also often included in reports and identifies the owners of calculations. • Radionuclide Viewer provides access to the Dose Coefficient File Package (DCFPAK) radiological data, and it complements the Mixture Manager tool. • Mixture Manager creates and manages radionuclides mixtures that are commonly used in other applications. • High Explosive Manager manages explosives and properties. • Chart Viewer is used for data charts such as meteorology charts and other charts specific to data needs. • Unit Converter converts numeric values to/from different units. This package includes object-oriented base code such as data objects describing the date, time, and location of an event; weather conditions; data types that support predefined ranges of values; a unit library, and others. The package also includes mathematic equations such as determining the distance between two points; erf functions; factorial functions; incidence fractions of probit curves; and others. Other features are customized user interface components for text fields; unit selectors (combo boxes); menus; panels; bug-tracking; and automated checks for software updates. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology & Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.

Collins, Ian↗

DOE OSTI2020

Correction to Unveiling the Role of Al 2 O 3 in Preventing Surface Reconstruction During High-Voltage Cycling of Lithium-Ion Batteries

A correction to this article was necessary to replace the original Figure 2 with the actual data in the revised Figure 2 shown here. An error was made while preparing the graphs from the neutron diffraction analysis software, and panel a was accidentally inserted into the panel b–d spots, such that all four panels were replicates. Since the original analysis of the data collected was made correctly, the conclusions and key points related to this section and the whole article remain unchanged. The revised goodness factors are slightly different because the refinements were repeated with small changes to the refinement conditions. The corresponding author has obtained approval from all coauthors in the article prior the submission of the Correction. The authors apologize for any inconveniences caused.

25 ENERGY STORAGE↗

DOE OSTI2024

RMCProfile7 : reverse Monte Carlo for multiphase systems

This work introduces a completely rewritten version of the programRMCProfile(version 7), big-box, reverse Monte Carlo modelling software for analysis of total scattering data. The major new feature ofRMCProfile7is the ability to refine multiple phases simultaneously, which is relevant for many current research areas such as energy materials, catalysis and engineering. Other new features include improved support for molecular potentials and rigid-body refinements, as well as multiple different data sets. An empirical resolution correction and calculation of the pair distribution function as a back-Fourier transform are now also available.RMCProfile7is freely available for download at https://rmcprofile.ornl.gov/.

Chemistry↗

DOE OSTI2014

SU-E-T-76: Comparing Homogeneity Between Gafchromic Film EBT2 and EBT3

Purpose: We found out that homogeneity of EBT2 was different among lot numbers in previous study. Variation in local homogeneity of EBT3 among several lot numbers has not been reported. In this study, we investigated film homogeneity of Gafcrhomic EBT3 films compared with EBT2 films. Methods: All sheets from five lots were cut into 12 pieces to investigate film homogeneity, and were irradiated at 0.5, 2, and 3 Gy. To investigate intra- and inter-sheet uniformity, five sheets from five lots were exposed to 2 Gy: intra-sheet uniformity was evaluated by the coefficient of variation of homogeneity for all pieces of a single sheet, and inter-sheet uniformity was evaluated by the coefficient of variation of homogeneity among the same piece numbers in the five sheets. To investigate the difference of ADC value in various doses, a single sheet from each of five lots was irradiated at 0.5 Gy and 3 Gy in addition to 2 Gy. A scan resolution of 72 dots per inch (dpi) and color depth of 48-bit RGB were used. Films were analyzed by the inhouse software; Average of ADC value in center ROI and profile X and Y axis were measured. Results and Conclusion: Intra-sheet uniformity of non-irradiated EBT2 films were ranged from 0.1% to 0.4%, however that of irradiated EBT2 films were ranged from 0.2% to 1.5%. On the other hand, intra-sheet uniformity of irradiated and non-irradiated EBT3 films were from 0.2% to 0.6%. Inter-sheet uniformity of all films were less than 0.5%. It was interesting point that homogeneity of EBT3 between no-irradiated and irradiated films were similar value, whereas EBT2 had dose dependence of homogeneity in ADC value evaluation. These results suggested that EBT3 homogeneity was corrected by this feature.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2014

SU-E-CAMPUS-T-05: Validation of High-Resolution 3D Patient QA for Proton Pencil Beam Scanning and IMPT by Polymer Gel Dosimetry

Purpose: Validation of high-resolution 3D patient QA for proton pencil beam scanning and IMPT by polymer gel dosimetry. Methods: Four BANG3Pro polymer gel dosimeters (manufactured by MGS Research Inc, Madison, CT) were used for patient QA at the Robert's Proton Therapy Center (RPTC, Philadelphia, PA). All dosimeters were sealed in identical thin-wall Pyrex glass spheres. Each dosimeter contained a set of markers for 3D registration purposes. The dosimeters were mounted in a consistent and reproducible manner using a custom build holder. Two proton pencil beam scanning plans were designed using Varian Eclipse™ treatment planning system: 1) A two-field intensity modulated proton therapy (IMPT) plan and 2) one single field uniform dose (SFUD) plan. The IMPT fields were evaluated as a composite plan and individual fields, the SFUD plan was delivered as a single field plan.Laser CT scanning was performed using the manufacturer's OCTOPUS-IQ axial transmission laser CT scanner using a 1 mm slice thickness. 3D registration, analysis, and OD/cm to absorbed dose calibrations were perfomed using DICOM RT-Dose and CT files, and software developed by the manufacturer. 3D delta index, a metric equivalent to the gamma tool, was used for dose comparison. Results: Very good agreement with single IMPT fields and with SFUD was obtained. Composite IMPT fields had a less satisfactory agreement. The single fields had 3D delta index passing rates (3% dose difference, 3 mm DTA) of 98.98% and 94.91%. The composite 3D delta index passing rate was 80.80%. The SFUD passing rate was 93.77%. Required shifts of the dose distributions were less than 4 mm. Conclusion: A formulation of the BANG3Pro polymer gel dosimeter, suitable for 3D QA of proton patient plans is established and validated. Likewise, the mailed QA analysis service provided by the manufacturer is a practical option when required resources are unavailable. We fully disclose that the subject of this research regards a production of MGS Research, Inc.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2015

SU-E-T-570: New Quality Assurance Method Using Motion Tracking for 6D Robotic Couches

Purpose: To accommodate geometrically accurate patient positioning, a robotic couch that is capable of 6-degrees of freedom has been introduced. However, conventional couch QA methods are not sufficient to enable the necessary accuracy of tests. Therefore, we have developed a camera based motion detection and geometry calibration system for couch QA. Methods: Employing a Visual-Tracking System (VTS, BonitaB10, Vicon, UK) which tracks infrared reflective(IR) markers, camera calibration was conducted using a 5.7 × 5.7 × 5.7 cm{sup 3} cube attached with IR markers at each corner. After positioning a robotic-couch at the origin with the cube on the table top, 3D coordinates of the cube’s eight corners were acquired by VTS in the VTS coordinate system. Next, positions in reference coordinates (roomcoordinates) were assigned using the known relation between each point. Finally, camera calibration was completed by finding a transformation matrix between VTS and reference coordinate systems and by applying a pseudo inverse matrix method. After the calibration, the accuracy of linear and rotational motions as well as couch sagging could be measured by analyzing the continuously acquired data of the cube while the couch moves to a designated position. Accuracy of the developed software was verified through comparison with measurement data when using a Laser tracker (FARO, Lake Mary, USA) for a robotic-couch installed for proton therapy. Results: VTS system could track couch motion accurately and measured position in room-coordinates. The VTS measurements and Laser tracker data agreed within 1% of difference for linear and rotational motions. Also because the program analyzes motion in 3-Dimension, it can compute couch sagging. Conclusion: Developed QA system provides submillimeter/ degree accuracy which fulfills the high-end couch QA. This work was supported by the National Research Foundation of Korea funded by Ministry of Science, ICT & Future Planning. (2013M2A2A7043507 and 2012M3A9B6055201)

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2016

SU-F-R-36: Validating Quantitative Radiomic Texture Features for Oncologic PET: A Digital Phantom Study

Purpose: Radiomic texture features derived from the oncologic PET have recently been brought under intense investigation within the context of patient stratification and treatment outcome prediction in a variety of cancer types; however, their validity has not yet been examined. This work is aimed to validate radiomic PET texture metrics through the use of realistic simulations in the ground truth setting. Methods: Simulation of FDG-PET was conducted by applying the Zubal phantom as an attenuation map to the SimSET software package that employs Monte Carlo techniques to model the physical process of emission imaging. A total of 15 irregularly-shaped lesions featuring heterogeneous activity distribution were simulated. For each simulated lesion, 28 texture features in relation to the intensity histograms (GLIH), grey-level co-occurrence matrices (GLCOM), neighborhood difference matrices (GLNDM), and zone size matrices (GLZSM) were evaluated and compared with their respective values extracted from the ground truth activity map. Results: In reference to the values from the ground truth images, texture parameters appearing on the simulated data varied with a range of 0.73–3026.2% for GLIH-based, 0.02–100.1% for GLCOM-based, 1.11–173.8% for GLNDM-based, and 0.35–66.3% for GLZSM-based. For majority of the examined texture metrics (16/28), their values on the simulated data differed significantly from those from the ground truth images (P-value ranges from <0.0001 to 0.04). Features not exhibiting significant difference comprised of GLIH-based standard deviation, GLCO-based energy and entropy, GLND-based coarseness and contrast, and GLZS-based low gray-level zone emphasis, high gray-level zone emphasis, short zone low gray-level emphasis, long zone low gray-level emphasis, long zone high gray-level emphasis, and zone size nonuniformity. Conclusion: The extent to which PET imaging disturbs texture appearance is feature-dependent and could be substantial. It is thus advised that use of PET texture parameters for predictive and prognostic measurements in oncologic setting awaits further systematic and critical evaluation.

60 APPLIED LIFE SCIENCES↗

DOE OSTI2025

TrioSim: A Lightweight Simulator for Large-Scale DNN Workloads on Multi-GPU Systems

Deep Neural Networks (DNNs) have become increasingly capable of performing tasks ranging from image recognition to content generation. The training and inference of DNNs heavily rely on GPUs, as GPUs' massively parallel architecture delivers extremely high computing capability. With the growing complexity of DNNs and the size of training datasets, training DNNs with a large number of GPUs is becoming a prevalent strategy. Researchers have been exploring how to design software and hardware systems for GPU farms to achieve the best utilization, efficiency, and DNN accuracy during training or inference. However, when designing and deploying such systems, designers usually rely on testing on physical hardware platforms equipped with many GPUs, incurring high costs that are almost prohibitive for system designers to test different configurations and designs, even for highly resourceful companies. While an alternative solution is to test on GPU simulators, they are often too slow for these l

Li, Ying [William & Mary, Williamsburg, VA, USA] (↗

DOE OSTI2014

KONGMING: Performance Prediction in the Cloud via Multidimensional Interference Surrogates

As more and more applications are deployed in the cloud, it is important for both the user and the operator of the cloud that the resources of the cloud are utilized efficiently. Virtualization and workload consolidation techniques are pervasively applied in the cloud to increase resource utilization while providing isolated execution environments for different users. While virtualization hides the architectural details of the underlying hardware, it can also increase the variability in application execution times due to heterogeneity in available hardware, and interference from other applications sharing the same hardware resources. This reduces both the productivity of cloud platforms and limits the degree to which software colocation can be used to increase its efficiency.

97 MATHEMATICS AND COMPUTING↗

DOE OSTI2021

Implementation of Plot File Testing in the DYNA3D/ParaDyn Software Quality Assurance Suite

Automated testing of DYNA3D/ParaDyn plot files was added to the DYNA3D/ParaDyn software quality assurance (SQA) test suite. The new capability extracts select data from the plot files generated during each verification run and compares it to the same baseline answers used to verify the problem. Deviations between baseline answers and plot file values are reported in the same manner as solution discrepancies, and differences in precision levels between the baseline answers and plot file results are accounted for. The new testing leverages the existing SQA test suite framework and test problems and the Python Mili reader and minimally increases the overall run time (< 5%) of the SQA test suite. This new capability provides incremental end-toend testing of the most common DYNA3D/ParaDyn simulation workflows.

42 ENGINEERING↗

DOE OSTI2017

Fault detection in PV systems

A practical fault detection approach for PV systems intended for online implementation is developed. The fault detection model here is built using artificial neural network. initially the photovoltaic system is simulated using MATLAB software and output power is collected for various combinations of irradiance and temperature. Data is first collected for normal operating condition and then four types of faults are simulated and data are collected for faulty conditions. Four faults are considered here and they are: Line to Line faults with a small voltage difference, Line to line faults with a large voltage difference, degradation fault and open-circuit fault. This data is then used to train the neural network and to develop the fault detection model. The fault detection model takes irradiance, temperature and power as the input and accurately gives the type of fault in the PV system as the output. This system is a generalized one as any PV module datasheet can be used to simulate the Photovoltaic system and also this fault detection system can be implemented online with the use of data acquisition system.

14 SOLAR ENERGY↗

DOE OSTI2024

Systematic and objective evaluation of Earth system models: PCMDI Metrics Package (PMP) version 3

Systematic, routine, and comprehensive evaluation of Earth system models (ESMs) facilitates benchmarking improvement across model generations and identifying the strengths and weaknesses of different model configurations. By gauging the consistency between models and observations, this endeavor is becoming increasingly necessary to objectively synthesize the thousands of simulations contributed to the Coupled Model Intercomparison Project (CMIP) to date. The Program for Climate Model Diagnosis and Intercomparison (PCMDI) Metrics Package (PMP) is an open-source Python software package that provides quick-look objective comparisons of ESMs with one another and with observations. The comparisons include metrics of large- to global-scale climatologies, tropical inter-annual and intra-seasonal variability modes such as the El Niño–Southern Oscillation (ENSO) and Madden–Julian Oscillation (MJO), extratropical modes of variability, regional monsoons, cloud radiative feedbacks, and high-frequency characteristics of simulated precipitation, including its extremes. The PMP comparison results are produced using all model simulations contributed to CMIP6 and earlier CMIP phases. An important objective of the PMP is to document the performance of ESMs participating in the recent phases of CMIP, together with providing version-controlled information for all datasets, software packages, and analysis codes being used in the evaluation process. Among other purposes, this also enables modeling groups to assess performance changes during the ESM development cycle in the context of the error distribution of the multi-model ensemble. Quantitative model evaluation provided by the PMP can assist modelers in their development priorities. In this paper, we provide an overview of the PMP, including its latest capabilities, and discuss its future direction.

54 ENVIRONMENTAL SCIENCES↗

DOE OSTI2015

A Comprehensive Validation Approach Using The RAVEN Code

The RAVEN computer code , developed at the Idaho National Laboratory, is a generic software framework to perform parametric and probabilistic analysis based on the response of complex system codes. RAVEN is a multi-purpose probabilistic and uncertainty quantification platform, capable to communicate with any system code. A natural extension of the RAVEN capabilities is the imple- mentation of an integrated validation methodology, involving several different metrics, that represent an evolution of the methods currently used in the field. The state-of-art vali- dation approaches use neither exploration of the input space through sampling strategies, nor a comprehensive variety of metrics needed to interpret the code responses, with respect experimental data. The RAVEN code allows to address both these lacks. In the following sections, the employed methodology, and its application to the newer developed thermal-hydraulic code RELAP-7, is reported.The validation approach has been applied on an integral effect experiment, representing natu- ral circulation, based on the activities performed by EG&G Idaho. Four different experiment configurations have been considered and nodalized.

PRA↗

DOE OSTI2017

Performance Assessment of a New Gamma Spectroscopy Toolkit: Peak Doctor and the Spectral Nondestructive Assay Platform (SNAP) - 17397

High resolution gamma spectroscopy (HRGS) is a widely used technique for non-destructive characterization of nuclear materials, and assay of radioactive waste. The ability to accurately evaluate raw spectral data is an important step in producing high-quality results. A spectral analysis application known as Peak Doctor has been developed under a Cooperative Research and Development Agreement (CRADA) between LANL and Pajarito Scientific Corporation (PSC). The software has undergone several years of testing and validation by the Radioactive Waste Characterization Team of the LANL Waste Management Services Group (WM-SVS). PeakDoctor is designed to work with the Spectral Nondestructive Assay Platform (SNAP{sup TM}) to provide a complete HRGS analysis engine. SNAP{sup TM} performs model specific corrections for attenuation and geometry. These applications are the major components of a new toolkit designed primarily for portable far-field non-destructive assay. Peak Doctor performs a very accurate peak fit analysis with the goal of improving upon the capabilities of existing commercially available routines. It is designed to be user-configurable and can be customized to any given type of detector and any given type of spectrum. Peak Doctor was developed to resolve many of the inherent complexities in gamma ray spectra including overlapping peaks, complex multiplet regions, large step peaks, backscatter regions and Compton edges. Unlike most spectral analysis platforms, Peak Doctor does not rely on the energy calibration and detector resolution parameters that are saved by the operator in the spectrum file. Instead, key parameters are pre-defined for individual detectors. The software fits a continuum using a series of splines between a series of junctions or 'knots'. Fitting techniques are used to join the splines together to create a near-continuous multi-element curve. Optimizing the location of the knots is one of Peak Doctor's most powerful features. The knots are initially configured using a pre-defined list and are removed or added automatically during the fitting process. Knots are also created when new features are identified such as Step Peaks and Compton Edges. The user can also manually specify knots in order to improve the continuum fit. The initial fit is improved on by removing any outlier regions (which are converted to peaks) and the continuum fitting process is repeated. At this stage, an experienced user can work interactively with the fit by manually converting peak regions to continuum or vice versa. The final step is to fit a series of peaks above the continuum based on detector parameters. Single and multiplet peaks are then processed by either the tailing (piecewise) or non-tailing (Gaussian) Levenberg Marquardt non-linear peak fitting routine depending on the user defined selection. Only a rough knowledge of the detector characteristics (energy calibration and resolution) is required for the fitting process to proceed with good accuracy. Any peaks that are missed can be manually added by the user and will also be fitted. Discontinuities in the peak / continuum fit can be rapidly identified by reviewing the 'residuals scale' plot. For waste streams that are well characterized, it is often the case that routinely encountered spectra will have similar peaks and continuum features. For these cases a handy 'One Step' method is available that proceeds in an automated fashion without user interaction. Peak Doctor has been configured with a set of default spectrum types including plutonium / transuranic waste (including Weapons Grade Pu, Heat Source Pu, Am-241, Am-243 and Np-237), depleted or enriched uranium, nuclear power plant / intermediate level waste (with fission and activation products such as Cs-137 and Co-60) as well as Naturally Occurring Radioactive Materials (NORM). The user can easily add new spectrum types for specific waste streams or other types of radiological / special nuclear materials. The output from PeakDoctor (including net peak area, centroid energy and a list of minimum detectable activity levels at pre-defined regions) is used by SNAP{sup TM} to complete the data analysis process. Isotope activities are calculated using configurable template-driven geometry and attenuation correction methods. The software accounts for matrix and container wall effects, collimator / angular corrections, detector efficiency (based on calibration curves) and stand-off distance. SNAP{sup TM} uses published algorithms incorporating a series of decision points during its operation to allow the analyst to provide logical input to guide the software during the analysis of each unique spectrum. The Peak Doctor / SNAP{sup TM} toolkit has been extensively tested and validated under a variety of conditions using 'benchmark' reference spectra. Test scenarios reported include HPGe-based measurements of well characterized uranium and plutonium standards and radioactive sources with a variety of different geometries and matrix materials including surrogate drums and boxes. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2018

Evaluating Support for OpenMP Offload Features

The OpenMP language features have been evolving to meet the rapid development in hardware platforms. DOE applications tend to push the bleeding edge of features ratified in the OpenMP specification and tend to expose the rough edges of the features' implementations. The software harness on DOE supercomputers such as Titan and (upcoming) Summit include Cray, Clang, Flang, XL and GCC compilers. It is critical, especially for Summit, that the compilers support OpenMP offloading features. This paper focuses on evaluating support for OpenMP 4.5 target offload directives across compiler implementations on Titan and Summitdev, an early access system, which is one generation removed from Summit's architecture enabling application teams to test the systems' architecture. Our tests not only evaluate the OpenMP implementations but also expose ambiguities in the OpenMP 4.5 specification. We also evaluate compiler implementations using kernels extracted from production DOE applications. This helps in assessing the interaction of different OpenMP directives independent of other application artifacts. We are aware that the implementations are constantly evolving and are advertised as having only partial OpenMP 4.x support. We see this as a synergistic effort to help identify and correct features that are required by DOE applications and prevent deployment delays later on. Going forward, we also plan to interact with standard benchmarking bodies like SPEC/HPG to donate our tests and mini-apps/kernels for potential inclusion in the next release versions of SPEC OMP and SPEC ACCEL benchmark suites.

Monsalve Diaz, Jose↗

DOE OSTI2013

Gelatin Microspheres: Correlation between Embolic Effect/Degradability and Cross-linkage/Particle Size

PurposeTo evaluate the embolic effect and degradability of gelatin microspheres (GMS) using various degrees of cross-linkage and particle sizes in rabbit renal artery embolization.MethodsFour types of GMS were used, as follows: 2 types of cross-linkage and 2 types of particle size. Twenty-four rabbits (6 in each group) were used for the renal artery embolization. Renal angiography was performed before and after embolization of right renal artery. Follow-up renal angiography was performed 2 days (n = 2), 5 days (n = 2), and 15 days (n = 2) after embolization in each group, and then kidneys were removed for histopathological evaluation. Vascular areas of the angiography were measured by Image J software, and the reperfusion rate was calculated. In renal specimens, residual GMS were checked and the degree of degradation was classified according to a 4-point scale.ResultsThe mean amounts of large- and small-particle-size GMS injected were 15.0 and 34.3 mg, respectively. Tissue necrosis was confirmed in each group; however, no difference was observed among groups. Renal reperfusion was observed more with small GMS than with large GMS. Renal reperfusion was also observed more with low cross-linked GMS than with high cross-linked GMS. In histopathological specimens, large GMS were confirmed in lobar artery, and small GMS were confirmed in lobular artery. Low cross-linked GMS completely degraded 15 days after embolization. In contrast, high cross-linked GMS were persistent 15 days after embolization.ConclusionDegree of cross-linkage and particle size affected degradability and reperfusion.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

DOE OSTI2023

A taxonomy of constraints in black-box simulation-based optimization

The types of constraints encountered in black-box simulation-based optimization problems differ significantly from those addressed in nonlinear programming. Here, we introduce a characterization of constraints to address this situation. We provide formal definitions for several constraint classes and present illustrative examples in the context of the resulting taxonomy. This taxonomy, denoted KARQ, is useful for modeling and problem formulation, as well as optimization software development and deployment. It can also be used as the basis for a dialog with practitioners in moving problems to increasingly solvable branches of optimization.

42 ENGINEERING↗