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At least 235 records · Page 13

Estuary ecosystem restoration: implementing and institutionalizing adaptive management: Institutionalizing adaptive management

We successfully implemented and institutionalized an adaptive management (AM) process for the Columbia Estuary Ecosystem Restoration Program, which is a large-scale restoration program focused on improving ecosystem conditions in the 234-km lower Columbia River and estuary. For our purpose, “institutionalized” means the AM process and restoration program are embedded in the work flow of the implementing agencies and affected parties. While plans outlining frameworks, processes, or approaches to AM of ecosystem restoration programs are commonplace, establishment for the long term is not. This paper presents the basic AM framework and explains how AM was implemented and institutionalized. Starting with a common goal, we pursued included a well-understood governance and decision-making structure, routine coordination and communication activities, data and information sharing, commitment from partners and upper agency management to the AM process, and meaningful cooperation among program managers and partners. The overall approach and steps to implement and institutionalize AM for ecosystem restoration explained here are applicable to situations where it has been less than successful or, as in our case, the restoration program is just getting started.

adaptive management↗

Implementation and experimental results of 4D tumor tracking using robotic couch

Purpose: This study presents the implementation and experimental results of a novel technique for 4D tumor tracking using a commercially available and commonly used treatment couch and evaluates the tumor tracking accuracy in clinical settings. Methods: Commercially available couch is capable of positioning the patient accurately; however, currently there is no provision for compensating physiological movement using the treatment couch in real-time. In this paper, a real-time couch tracking control technique is presented together with experimental results in tumor motion compensation in four dimensions (superior-inferior, lateral, anterior-posterior, and time). To implement real-time couch motion for tracking, a novel control system for the treatment couch was developed. The primary functional requirements for this novel technique were: (a) the treatment couch should maintain all previous/normal features for patient setup and positioning, (b) the new control system should be used as a parallel system when tumor tracking would be deployed, and (c) tracking could be performed in a single direction and/or concurrently in all three directions of the couch motion (longitudinal, lateral, and vertical). To the authors' best knowledge, the implementation of such technique to a regular treatment couch for tumor tracking has not been reported so far. To evaluate the performance of the tracking couch, we investigated the mechanical characteristics of the system such as system positioning resolution, repeatability, accuracy, and tracking performance. Performance of the tracking system was evaluated using dosimetric test as an endpoint. To investigate the accuracy of real-time tracking in the clinical setting, the existing clinical treatment couch was replaced with our experimental couch and the linear accelerator was used to deliver 3D conformal radiation therapy (3D-CRT) and intensity modulated radiation therapy (IMRT) treatment plans with and without tracking. The results of radiation dose distribution from these two sets of experiments were compared and presented here. Results: The mechanical accuracies were 0.12, 0.14, and 0.18 mm in X, Y, and Z directions. The repeatability of the desired motion was within {+-}0.2 mm. The differences of central axis dose between the 3D-CRT stationary plan and two tracking plans with different motion trajectories were 0.21% and 1.19%. The absolute dose differences of both 3D tracking plans comparing to the stationary plan were 1.09% and 1.20%. Comparing the stationary IMRT plan with the tracking IMRT plan, it was observed that the central axis dose difference was -0.87% and the absolute difference of both IMRT plans was 0.55%. Conclusions: The experimental results revealed that the treatment couch could be successfully used for real-time tumor tracking with a high level of accuracy. It was demonstrated that 4D tumor tracking was feasible using existing couch with implementation of appropriate tracking methodology and with modifications in the control system.

60 APPLIED LIFE SCIENCES↗

SU-G-TeP4-11: Implementation of a Non-Measurement-Based Patient-Specific IMRT QA Program

Purpose: To implement a comprehensive non-measurement-based verification program for patient-specific IMRT QA Methods: Based on published guidelines, a robust IMRT QA program should assess the following components: 1) accuracy of dose calculation, 2) accuracy of data transfer from the treatment planning system (TPS) to the record-and-verify (RV) system, 3) treatment plan deliverability, and 4) accuracy of plan delivery. Results: We have implemented an IMRT QA program that consist of four components: 1) an independent re-calculation of the dose distribution in the patient anatomy with a commercial secondary dose calculation program: Mobius3D (Mobius Medical Systems, Houston, TX), with dose accuracy evaluation using gamma analysis, PTV mean dose, PTV coverage to 95%, and organ-at-risk mean dose; 2) an automated in-house-developed plan comparison system that compares all relevant plan parameters such as MU, MLC position, beam iso-center position, collimator, gantry, couch, field size settings, and bolus placement, etc. between the plan and the RV system; 3) use of the RV system to check the plan deliverability and further confirm using “mode-up” function on treatment console for plans receiving warning; and 4) implementation of a comprehensive weekly MLC QA, in addition to routine accelerator monthly and daily QA. Among 1200 verifications, there were 9 cases of suspicious calculations, 5 cases of delivery failure, no data transfer errors, and no failure of weekly MLC QA. These 9 suspicious cases were due to the PTV extending to the skin or to heterogeneity correction effects, which would not have been caught using phantom measurement-based QA. The delivery failure was due to the rounding variation of MLC position between the planning system and RV system. Conclusion: A very efficient, yet comprehensive, non-measurement-based patient-specific QA program has been implemented and used clinically for about 18 months with excellent results.

60 APPLIED LIFE SCIENCES↗

TH-EF-207A-03: Photon Counting Implementation Challenges Using An Electron Multiplying Charged-Coupled Device Based Micro-CT System

Purpose: To successfully implement and operate a photon counting scheme on an electron multiplying charged-coupled device (EMCCD) based micro-CT system. Methods: We built an EMCCD based micro-CT system and implemented a photon counting scheme. EMCCD detectors use avalanche transfer registries to multiply the input signal far above the readout noise floor. Due to intrinsic differences in the pixel array, using a global threshold for photon counting is not optimal. To address this shortcoming, we generated a threshold array based on sixty dark fields (no x-ray exposure). We calculated an average matrix and a variance matrix of the dark field sequence. The average matrix was used for the offset correction while the variance matrix was used to set individual pixel thresholds for the photon counting scheme. Three hundred photon counting frames were added for each projection and 360 projections were acquired for each object. The system was used to scan various objects followed by reconstruction using an FDK algorithm. Results: Examination of the projection images and reconstructed slices of the objects indicated clear interior detail free of beam hardening artifacts. This suggests successful implementation of the photon counting scheme on our EMCCD based micro-CT system. Conclusion: This work indicates that it is possible to implement and operate a photon counting scheme on an EMCCD based micro-CT system, suggesting that these devices might be able to operate at very low x-ray exposures in a photon counting mode. Such devices could have future implications in clinical CT protocols. NIH Grant R01EB002873; Toshiba Medical Systems Corp.

60 APPLIED LIFE SCIENCES↗

Quality Assurance Framework Implementation Guide for Isolated Community Power Systems

This implementation guide is a companion document to the 'Quality Assurance Framework for Mini-Grids' technical report. This document is intended to be used by one of the many stakeholder groups that take part in the implementation of isolated power systems. Although the QAF could be applied to a single system, it was designed primarily to be used within the context of a larger national or regional rural electrification program in which many individual systems are being installed. This guide includes a detailed overview of the Quality Assurance Framework and provides guidance focused on the implementation of the Framework from the perspective of the different stakeholders that are commonly involved in expanding energy development within specific communities or regions. For the successful long-term implementation of a specific rural electrification program using mini-grid systems, six key stakeholders have been identified that are typically engaged, each with a different set of priorities 1. Regulatory agency 2. Governmental ministry 3. System developers 4. Mini-utility 5. Investors 6. Customers/consumers. This document is broken into two distinct sections. The first focuses on the administrative processes in the development and operation of community-based mini-grid programs, while the second focuses on the process around the installation of the mini-grid project itself.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Implementation of the Jacobian-free Newton-Krylov method for solving the for solving the first-order ice sheet momentum balance

We have implemented the Jacobian-free Newton-Krylov (JFNK) method for solving the rst-order ice sheet momentum equation in order to improve the numerical performance of the Community Ice Sheet Model (CISM), the land ice component of the Community Earth System Model (CESM). Our JFNK implementation is based on signicant re-use of existing code. For example, our physics-based preconditioner uses the original Picard linear solver in CISM. For several test cases spanning a range of geometries and boundary conditions, our JFNK implementation is 1.84-3.62 times more efficient than the standard Picard solver in CISM. Importantly, this computational gain of JFNK over the Picard solver increases when rening the grid. Global convergence of the JFNK solver has been signicantly improved by rescaling the equation for the basal boundary condition and through the use of an inexact Newton method. While a diverse set of test cases show that our JFNK implementation is usually robust, for some problems it may fail to converge with increasing resolution (as does the Picard solver). Globalization through parameter continuation did not remedy this problem and future work to improve robustness will explore a combination of Picard and JFNK and the use of homotopy methods.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

ARCADIA and advanced methods licensing and implementation update

AREVA NP is implementing a consistent code and methodology suite for core design and safety analysis, based on first principles modeling with an extremely broad verification and validation data base. Thanks to the high computational power increase in the last decades methods' development and application now include capabilities that were not available in the past. An example is the 3D coupled transient core power distribution characterization, which allows more realistic modeling of plant behavior, removal of inaccuracies by high resolution and access to local information. Another one is the progressive replacement, respectively complement of old deterministic methods by order statistics. This paper provides an update of the current licensing and implementation status of the main AREVA NP new codes (ARCADIA, GALILEO, S-RELAP5) and their associated advanced methods for PWR applications. ARCADIA is the state-of-the-art neutron transport/ thermal-hydraulics (TH)/ thermal-mechanics (TM) code system for PWR applications. Development is completed, implementation started in France, the Netherlands, the U.S.A. and other countries. The extension to BWR applications is on-going. GALILEO is the state-of-the-art fuel rod performance code for PWR and BWR applications. Development is completed, implementation started in France and the U.S.A. S-RELAP5 is a thermal-hydraulic code that has been completely re-coded and modernized in terms of software architecture. S-RELAP5 has been successfully coupled with ARCADIA. It is shown that advanced codes and integrated methods for accident analysis are keys for extending the fuel cycle design space.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗

FUSRAP Case Study - Benefits and Lessons Learned from Implementation of a Modern Data Solution at Maywood - 18399

This paper focuses on data production and management practices dating back to 1999 that continue to evolve to support the project today. In 2000, the FUSRAP Maywood Project began using a software environmental data management system and laboratory information management system, developed by a single database administrator (DA) and authored in Microsoft Access{sup TM} (MS Access). The original databases included basic functionality including sample number assignment and label generation, tracking of LIMS gamma spec QC and assignment of basic qualifiers and basic database queries. The DA continued over the next fifteen years to refine the EDMS/LIMS by integrating project-specific data evaluation guidance document processes and Quality Assurance/Quality Control (QA/QC) charting and excursion warning tools. With the retirement of the original DA, the U.S. Army Corps of Engineers (USACE)-Cabrera Team procured and implemented a commercial-leaning solution using modern database tools and an established EDMS vendor. For the database transition process, the project team established and configured the new EDMS/LIMS with basic architecture and accessibility; evaluated existing workflows; established/revised LIMS and EDMS-related documentation (manuals and procedures); and conducted dry runs and validation testing. The overall team coordinated closely to facilitate a seamless transition from initial assessment and authoring, to data migration, and finally to resumption of normal ongoing operations. Key features of the new EDMS Subcontractor's software included lookup tables, an import wizard, data checking options and unique indexes. Since the database systems became operational, the technical staff gathered useful feedback from end users (e.g., lab staff, field engineers, task managers, and the third-party data validator) to refine the EDMS/LIMS operation. This feedback triggered improvements in the performance of onsite laboratory qualification forms, promoted consistency in sample ID numbers between the database sample planning screens and field chain-of-custodies, corrected bugs in the LIMS Duplicate Evaluation Report, eliminated data import issues such as blank, inconsistent or missing data from key fields. One of the advantages of the commercial database solution was that it allowed the project to cut cost over time due to the lower cost of database maintenance provided by the commercial database vendor versus the cost of an on-staff DA. Cost savings are estimated at $40,000 per year. There were also indirect cost savings resulting from implementation of the new database since it allowed better integration of the LIMS and EDMS. While there will always be challenges associated with long term records/data management for any old remediation site, the Maywood Team's approach to an upgraded EDMS/LIMS implementation serves as one element of the overall effort to enhance the integrity and reproducibility of critical data that supports the remediation program while at the same time, more effectively using available resources. These lessons-learned will enhance implementation of cost-effective solutions for similar environmental remediation sites. (authors)

97 MATHEMATICS AND COMPUTING↗

EM Program Expectations on Implementation of DOE O 458: Radiation Protection of Public/Environment - 19553

DOE Order 458.1, Radiation Protection of the Public and Environment, was issued in 2011. DOE sites were given 18 months to implement. The revised Order promulgates requirements for property clearance actions and independent verification. DOE Order 458.1 allows for preapproved authorized limits for the clearance of property. However, when property with the potential to contain residual radioactive material does not meet preapproved authorized limits, an authorized limits package must be developed. The Order contains a range of requirements for demonstrating with reasonable assurance that dose constraints are met for any actual or likely future use of the property to be released. EM has developed a draft guidance document that provides the elements of an authorized limits package. These elements are used to review all authorized limits packages that are submitted to EM. Expected elements include property description and process knowledge documentation, current and likely future use, the conceptual site model, dose modeling methodologies, specific authorized limits, dose- or concentration-based constraints, collective dose estimate to the potentially exposed population, stakeholder communications, description of the As Low As Reasonably Achievable (ALARA) analysis, implementation plan, evaluation of difficult to assess surfaces, and independent verification plan. The draft guidance document also provides further explanation of the desired elements of an independent verification (IV) plan. An IV plan should describe the planning phase, implementation phase, assessment phase, and decision phase of an activity. The planning phase includes scope and cost, concurrent with cleanup contractor procurement, and review and approval of site radiological survey clearance program and IV program plans. The implementation phase assures sufficient collection of data and adjustment can be made as necessary. During the assessment phase, data and reports are reviewed, and coordination between the clean-up contractor and IV personnel occurs. A decision of whether or not the clearance actions need to be altered occurs during the decision phase. IV certification that the clearance action is complete also occurs during the decision phase. Issuance of the final guidance document is meant to improve the consultation process and minimize iterative interactions with EM. Standardizing and formalizing property clearance and IV actions also helps assure that cleanup actions are transparent and sustainable for future scrutiny. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

A qualitative assessment of current CCF guidance based on a review of safety system digital implementation changes with evolving technology - 148

This paper is a summary of a study performed in support of the US Nuclear Regulatory Commission (NRC) to evaluate current policy on software common-cause failure (CCF). The study reported in this paper is one of several that contributed to the technical basis to inform NRC staff. The study first reviewed policies and assessment guidance as discussed in the Staff Requirements Memorandum to the Secretary of the Commission, Office of the NRC (SECY) 93-087, Policy, Technical, and Licensing Issues Pertaining to Evolutionary and Advanced Light Water Reactor (ALWR) Designs, and Branch Technical Position (BTP) 7-19, Guidance on Evaluation of Defense-in-Depth and Diversity in Digital Computer-Based Instrumentation and Control Systems, as well as Chapter 7, 'Instrumentation and Controls', in NUREG-0800, Standard Review Plan for Review of Safety Analysis Reports for Nuclear Power Plants. The study then examined instrumentation and controls (I and C) technology implementations in nuclear power plants in the light of current CCF guidance. The intent was to assess whether the current position on CCF remains appropriate given the evolutions in digital safety system implementations and, if gaps in the guidance were found, to provide recommendations as to how these gaps could be closed. The methodology adopted was to review the vendors' technology and software implementation processes for digital safety systems as technology evolved. The following three representative safety systems were selected to provide illustrative examples: - Eagle 21 was selected to represent vintage microprocessor-based technology used from the 1980's to mid-1990's, - TELEPERM XS (TXS) was selected to represent second generation microprocessor-based technology used from the mid-1990's to the 2000's, and - The advanced logic system (ALS) was selected to represent the latest trend of using technology based on field programmable gate arrays (FPGAs). Technology implementations were reviewed in light of the basic premise of the NRC in BTP 7-19 (Revision 6), that software-based or software-logic-based digital system development errors are a credible source of CCF and therefore are susceptible to CCF because identical copies of the software-based logic and architecture are present in redundant divisions of safety-related systems. BTP 7-19 categorizes firmware and logic developed from software-based development systems all under software. (authors)

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

Status of Activities to Implement a Sustainable System of MC&A Equipment and Methodological Support at Rosatom Facilities

Under the U.S.-Russian Material Protection, Control and Accounting (MPC&A) Program, the Material Control and Accounting Measurements (MCAM) Project has supported a joint U.S.-Russian effort to coordinate improvements of the Russian MC&A measurement system. These efforts have resulted in the development of a MC&A Equipment and Methodological Support (MEMS) Strategic Plan (SP), developed by the Russian MEM Working Group. The MEMS SP covers implementation of MC&A measurement equipment, as well as the development, attestation and implementation of measurement methodologies and reference materials at the facility and industry levels. This paper provides an overview of the activities conducted under the MEMS SP, as well as a status on current efforts to develop reference materials, implement destructive and nondestructive assay measurement methodologies, and implement sample exchange, scrap and holdup measurement programs across Russian nuclear facilities.

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗

The Kokkos OpenMPTarget Backend: Implementation and Lessons Learned

As the supercomputing landscape diversifies, solutions such as Kokkos to write vendor agnostic applications and libraries have risen in popularity. Kokkos provides a programming model designed for performance portability, which allows developers to write a single source implementation that can run efficiently on various architectures. At its heart, Kokkos maps parallel algorithms to architecture and vendor specific backends written in lower level programming models such as CUDA and HIP. Another approach to writing vendor agnostic parallel code is using OpenMP’s directives based approach, which lets developers annotate code to express parallelism. It is implemented at the compiler level and is supported by all major high performance computing vendors, as well as the primary Open Source toolchains GNU and LLVM. Since its inception, Kokkos has used OpenMP to parallelize on CPU architectures. In this paper, we explore leveraging OpenMP for a GPU backend and discuss the challenges we encountered when mapping the Kokkos APIs and semantics to OpenMP target constructs. As an exemplar workload we chose a simple conjugate gradient solver for sparse matrices. We find that performance on NVIDIA and AMD GPUs varies widely based on details of the implementation strategy and the chosen compiler. Furthermore, the performance of the OpenMP implementations decreases with increasing complexity of the investigated algorithms.

Gayatri, Rahulkumar↗

Graph 500 in OpenSHMEM, In: OpenSHMEM 2014: OpenSHMEM and Related Technologies. Experiences, Implementations, and Technologies

This document describes the effort to implement the Graph 500 benchmark using OpenSHMEM based on the MPI-2 one-side version. The Graph 500 benchmark performs a breadth-first search in parallel on a large randomly generated undirected graph and can be implemented using basic MPI-1 and MPI-2 one-sided communication. Graph 500 requires atomic bit-wise operations on unsigned long integers but neither atomic bit-wise operations nor OpenSHMEM for unsigned long are available in OpenSHEM. Such needed bit-wise atomic operations and support for unsigned long are implemented using atomic condition swap (CSWAP) on signed long integers. Preliminary results on comparing the OpenSHMEM and MPI-2 one-sided implementations on a Silicon Graphics Incorporated (SGI) cluster and the Cray XK7 are presented.

Computer Science↗

Thermodynamic Implementations of Quantum Processes

Abstract Recent understanding of the thermodynamics of small-scale systems have enabled the characterization of the thermodynamic requirements of implementing quantum processes for fixed input states. Here, we extend these results to construct optimal universal implementations of a given process, that is, implementations that are accurate for any possible input state even after many independent and identically distributed (i.i.d.) repetitions of the process. We find that the optimal work cost rate of such an implementation is given by the thermodynamic capacity of the process, which is a single-letter and additive quantity defined as the maximal difference in relative entropy to the thermal state between the input and the output of the channel. Beyond being a thermodynamic analogue of the reverse Shannon theorem for quantum channels, our results introduce a new notion of quantum typicality and present a thermodynamic application of convex-split methods.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

Occupant behavior models: A critical review of implementation and representation approaches in building performance simulation programs

Occupant behavior (OB) in buildings is a leading factor influencing energy use in buildings. Quantifying this influence requires the integration of OB models with building performance simulation (BPS). This study reviews approaches to representing and implementing OB models in today’s popular BPS programs, and discusses weaknesses and strengths of these approaches and key issues in integrating of OB models with BPS programs. Two of the key findings are: (1) a common data model is needed to standardize the representation of OB models, enabling their flexibility and exchange among BPS programs and user applications; the data model can be implemented using a standard syntax (e.g., in the form of XML schema), and (2) a modular software implementation of OB models, such as functional mock-up units for co-simulation, adopting the common data model, has advantages in providing a robust and interoperable integration with multiple BPS programs. Such common OB model representation and implementation approaches help standardize the input structures of OB models, enable collaborative development of a shared library of OB models, and allow for rapid and widespread integration of OB models with BPS programs to improve the simulation of occupant behavior and quantification of their impact on building performance.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

A new procedure for implementing the modified inherent strain method with improved accuracy in predicting both residual stress and deformation for laser powder bed fusion

As a metal additive manufacturing (AM) process, laser powder bed fusion (L-PBF) has been widely used to produce parts with complex geometries. The large thermal gradient caused by the fast, intense, and repeated laser scanning induces significant residual deformation and stress to the as-built parts, which increase manufacturing difficulty and geometrical inaccuracy as a result. The modified inherent strain (MIS) method exploiting multiscale process simulations was developed to simulate residual deformation accurately and efficiently. However, the existing procedure of implementing the MIS method is found to give inaccurate residual stress prediction. Here in this work, a new implementation procedure for the MIS method is proposed to improve the simulation accuracy of residual stress without degrading the residual deformation prediction. The new procedure concerns the application of inherent strains to the part-scale layer-by-layer finite element model to obtain residual stress and deformation field. While the existing implementation of the part-scale MIS model involves only mechanical properties at ambient temperature, the new procedure adds one more solution step employing mechanical properties at an elevated temperature determined from the inherent strain extraction step. Both numerical and experimental studies are conducted to validate the proposed new implementation procedure. It shows that by using the new procedure, the MIS-based simulation can predict both residual stress and deformation of as-built L-PBF metal parts with good accuracy.

36 MATERIALS SCIENCE↗

Clinicians’ and Pharmacists’ Reported Implementation of Vaccination Practices for Adults

Introduction: Despite the proven effectiveness of immunization in preventing morbidity and mortality, adult vaccines remain underutilized. The objective of this study was to describe clinicians’ and pharmacists’ self-reported implementation of the Standards for Adult Immunization Practice (“the Standards”; i.e., routine assessment, recommendation, and administration/referral for needed vaccines, and documentation of administered vaccines, including in immunization information systems). Methods: Two Internet panel surveys (one among clinicians and one among pharmacists) were conducted during February–March 2017 and asked respondents about their practice’s implementation of the Standards. T-tests assessed associations between clinician medical specialty, vaccine type, and each component of the Standards (March–August 2017). Results: Implementation of the Standards varied substantially by vaccine and provider type. For example, >80.0% of providers, including obstetrician/gynecologists and subspecialists, assessed for and recommended influenza vaccine. However, 24.3% of obstetrician/gynecologists and 48.9% of subspecialists did not stock influenza vaccine for administration. Although zoster vaccine was recommended by >89.0% of primary care providers, <58.0% stocked the vaccine; by contrast, 91.6% of pharmacists stocked zoster vaccine. Vaccine needs assessments, recommendations, and stocking/referrals also varied by provider type for pneumococcal; tetanus, diphtheria, acellular pertussis; tetanus diphtheria; human papillomavirus; and hepatitis B vaccines. Conclusions: This report highlights gaps in access to vaccines recommended for adults across the spectrum of provider specialties. Greater implementation of the Standards by all providers could improve adult vaccination rates in the U.S. by reducing missed opportunities to recommend vaccinations and either vaccinate or refer patients to vaccine providers.

60 APPLIED LIFE SCIENCES↗

Implementation of Triply Periodic Minimal Surfaces (TPMS) as surface objects in OpenMC

Triply Periodic Minimal Surfaces (TPMS) represent a promising geometry for future fuel designs due to their significant surface-to-volume ratio, which facilitates efficient cooling of nuclear fuel, a crucial factor for safety and efficiency. Demonstrating the remarkable capabilities of TPMS fuel requires initial modeling and simulation. This paper presents an implementation of TPMS in the Monte Carlo code OpenMC, enabling reactor physics modeling of TPMS. Here, the primary advantages over traditional methods using CAD files include reduced memory requirements for computations and high-fidelity implementation. This implementation has been tested against CAD files loaded in Serpent2, yielding promising results with low biases in the $k_{\textrm{eff}}$, comparable to biases in the material balance sheet. The implementation presented in this work will be used in future reactor physics computations related to new reactor designs involving TPMS-based fuels.

11 - NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗