@article{ni_hou_2023, title={An Efficient High-to-Low Iterative Method for Light Water Reactor Analysis Based on NEAMS Tools}, volume={197}, ISSN={0029-5639 1943-748X}, url={http://dx.doi.org/10.1080/00295639.2022.2158706}, DOI={10.1080/00295639.2022.2158706}, abstractNote={Abstract The so-called two-step method involving the consecutive lattice physics and core simulation has been successfully and widely used in large-scale nuclear reactor calculations thanks to its superior computational efficiency and a satisfactory level of accuracy. However, its performance is challenged by the ever-increasing level of heterogeneity in core designs due to the use of infinite lattice approximation in the lattice calculation and its inability to update cross-section sets according to the core environment change. This paper introduces an alternative approach for light water reactor steady-state core analysis. During the core calculation process, iterations between the local lattice transport calculation and the global core nodal calculation are conducted. These iterations continuously update the boundary condition applied to the lattice model and generate updated cross-section sets. This is done through the iteration between the local lattice transport calculation and the global core nodal simulation. The neutronics high-to-low (Hi2Lo) scheme was formulated using Nuclear Energy Advanced Modeling and Simulation or NEAMS codes, in particular, with the modified PROTEUS-MOC and PROTEUS-NODAL serving as the transport lattice solver and full-core nodal solver, respectively. The verification of the implemented Hi2Lo iterative scheme on the two-dimensional C5G7-TD benchmark problem shows that the Hi2Lo scheme outperforms the two-step approach in terms of prediction accuracy for the key responses of interest (e.g., the system eigenvalue and power distribution) at a computational cost lower than that of the direct full-core transport calculation. To further improve its efficiency, an acceleration method has been developed and implemented for the Hi2Lo approach, and the results indicate that the acceleration method can significantly reduce the run time of a full-core transport solution by a factor of 14 while generating solutions with comparable accuracy.}, number={8}, journal={Nuclear Science and Engineering}, publisher={Informa UK Limited}, author={Ni, Kan and Hou, Jason}, year={2023}, month={Feb}, pages={1700–1716} }
 @phdthesis{ni_2022, title={A High-to-low Iterative Method for Light Water Reactor Analysis}, author={Ni, Kan}, year={2022} }
 @inproceedings{ni_hou_2022, title={An Efficient High-To-Low Informing Scheme for 3D and Steady-state Multiphysics Simulations}, booktitle={OCED/NEA WPRS Workshop}, publisher={Nuclear Energy Agency}, author={Ni, K. and Hou, J.}, year={2022} }
 @inproceedings{ni_hou_2022, place={Pittsburgh, PA}, title={An Efficient High-To-Low Informing Scheme for Core Neutronics Calculations Based on NEAMS Tools}, booktitle={International Conference on Physics of Reactors 2022 (PHYSOR 2022)}, publisher={doi.org/10.13182/PHYSOR22-37331}, author={Ni, Kan and Hou, Jason}, year={2022}, month={May}, pages={2551–2560} }
 @inproceedings{ni_cao_stauff_hou_2022, place={Pittsburgh, PA}, title={Assessment of Griffin Cross-Section Interpolation Capability on TRISO-Fueled Heat-Pipe Micro-Reactor}, booktitle={International Conference on Physics of Reactors 2022 (PHYSOR 2022)}, publisher={doi.org/10.13182/PHYSOR22-37536}, author={Ni, Kan and Cao, Yan and Stauff, Nicolas and Hou, Jason}, year={2022}, pages={3097–3106} }
 @inproceedings{fustero_powell_ni_etc._2022, place={Phoenix, AZ}, title={High to Low Multi-Physics Modeling and Uncertainty Propagation using NEAMS Tools}, booktitle={2022 ANS Winter Meeting}, author={Fustero, Joseph and Powell, Walker and Ni, Kan and etc.}, year={2022}, month={Nov} }
 @inproceedings{ni_nguyen_hou_2022, title={Multi-parametric Cross-section and Decusping Function Generation in Support of C5G7 Phase II-2 Exercises}, booktitle={OCED/NEA WPRS Workshop}, publisher={Nuclear Energy Agency}, author={Ni, K. and Nguyen, K. and Hou, J.}, year={2022} }
 @inproceedings{williams_howe_hou_ni_2022, title={Neutronics Modeling of the Pulsed Plasma Rocket Reactor Using Rattlesnake}, booktitle={International Conference on Physics of Reactors 2022 (PHYSOR 2022)}, author={Williams, J. and Howe, T. and Hou, J. and Ni, K.}, year={2022} }
 @book{stauff_miao_bhattacharya_cao_ni_thomas_2022, title={Versatile Heat Transfer Module}, url={http://dx.doi.org/10.2172/1844344}, DOI={10.2172/1844344}, abstractNote={,}, institution={Office of Scientific and Technical Information (OSTI)}, author={Stauff, Nicolas and Miao, Yinbin and Bhattacharya, Sumit and Cao, Yan and Ni, Kan and Thomas, Justin}, year={2022}, month={Jan} }
 @book{stauff_mo_cao_thomas_miao_zou_nunez_shemon_feng_ni_2021, title={Detailed analyses of a TRISO-fueled microreactor: Modeling of a Micro-Reactor System using NEAMS Tools}, url={http://dx.doi.org/10.2172/1826285}, DOI={10.2172/1826285}, abstractNote={particles on the particle shadowing effect using a homogenized compact region surrounding a particle of interest at the center. The self-shielded cross sections of the particle at the center are determined iteratively since the cross sections of the homogenized compact region are calculated using them. For the energy range above 100 keV where the fuel-to-moderator ratio is more important than the random distribution of particles, a single particle unit-cell model is used by preserving the average amount of moderator per fuel particle in the system. The three self-shielding methods implemented in MC2-3 were tested using numerical benchmark problems made based on fuel compact problems of a prismatic-type very high temperature reactor. Test results indicated that the ILSS method produced slightly better results than the SCALE and Sanchez-Pomraning methods, compared to the Serpent-2 Monte Carlo results obtained with 25 independent random particle configurations. The SCALE and Sanchez-Pomraning methods tend to underestimate the heterogeneity effect by 150 and 100 pcm, respectively, while the new ILSS method overestimates the heterogeneity effect by 70 pcm. In future, the new self-shielding method will be extended to perform pebble calculations and compare results with those from the SCALE and Sanchez-Pomraning methods. Furthermore, the new method will be optimized for practical applications to on-the-fly resonance treatment for lattice or whole-core calculations for advanced reactors.}, institution={Office of Scientific and Technical Information (OSTI)}, author={Stauff, N. and Mo, K. and Cao, Y. and Thomas, J. and Miao, Y. and Zou, L. and Nunez, D. and Shemon, E. and Feng, B. and Ni, K.}, year={2021}, month={Sep} }
 @inproceedings{ni_hou_avramova_2021, place={Raleigh, United States}, title={Development of a High-To-Low Informing Scheme for Core Neutronics Calculations Based on NEAMS Tools}, url={https://www.researchgate.net/profile/Kan-Ni/publication/355855874_Development_of_a_High-to-Low_Informing_Scheme_for_Core_Neutronics_Calculations_Based_on_NEAMS_Tools/links/618157b60be8ec17a9610891/Development-of-a-High-to-Low-Informing-Scheme-for-Core-Neutronics-Calculations-Based-on-NEAMS-Tools.pdf}, DOI={dx.doi.org/10.13182/M&C21-33736}, booktitle={The International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2021)}, publisher={ANS}, author={Ni, Kan and Hou, Jason and Avramova, Maria}, year={2021}, month={Oct} }
 @inproceedings{ni_hou_avramova_2020, title={Implementation and comparison of lattice module and discontinuity factors module in PROTEUS toolsets}, volume={2020-March}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85108414539&partnerID=MN8TOARS}, DOI={10.1051/epjconf/202124702035}, abstractNote={State-of-the-art core nodal diffusion calculation involves the use of assembly discontinuity factor (ADF) to improve computational accuracy by introducing degree of freedom describing the relationship between interfacial discontinuities in nodal calculation [1]. The form of ADF known as the Flux based ADF (FDF) generated from flux information is recommended in the conventional two-level core calculation scheme. The multi-group cross-sections were generated using SCALE 6.2 NEWT and verified with KENO-VI [2]. A lattice module has been created for the high-fidelity neutron transport code MOCEX [3] to generate the group constants and side-independent ADFs. This new capability is verified against the reference code SCALE 6.2 NEWT under both serial and parallel modes. The implementation of ADF is performed in this work and further verified by comparing core keff. The calculation results show that the newly implemented ADF module consistently improved the accuracy of the PROTEUS-NODAL (NODAL) diffusion solver, which will become an affordable candidate for the following research of High-to-Low (Hi2Lo) transport-to-diffusion informing scheme [4].}, booktitle={International Conference on Physics of Reactors: Transition to a Scalable Nuclear Future, PHYSOR 2020}, author={Ni, K. and Hou, J. and Avramova, M.}, year={2020}, pages={394–401} }
 @inproceedings{hou_ni_hawari_2019, title={An artificial neural network based anomaly detection algorithm for nuclear power plants}, volume={120}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85092137439&partnerID=MN8TOARS}, booktitle={Transactions of the American Nuclear Society}, author={Hou, J. and Ni, K. and Hawari, A.}, year={2019}, pages={219–222} }
 @inproceedings{ni_zeng_hou_2018, title={Generation of Covariance Matrix Based on Updated Nuclear Data Library Using NJOY}, booktitle={Workshop of OECD/NEA Benchmark for Uncertainty Analysis in Best-Estimate Modelling for Design, Operation and Safety Analysis of LWRs (LWR-UAM-12)}, author={Ni, K. and Zeng, K. and Hou, J.}, year={2018} }
 @inproceedings{ni_trivedi_hou_2018, title={Processing of Covariance Information from Updated Nuclear Data Library Using NJOY}, booktitle={ANS (Best Estimate Plus Uncertainty) BEPU workshop of UAM-SFR}, author={Ni, K. and Trivedi, I. and Hou, J.}, year={2018} }
 @article{ni_2016, title={An Analysis on the Present Situation and Prospect of Nuclear Power Development in China}, journal={Industry A}, author={Ni, K.}, year={2016}, pages={178} }
 @article{ni_2016, title={The Influence of Nuclear Energy Security and Development on Nuclear Energy Structure Adjustment in China}, volume={2}, journal={Industry}, author={Ni, K.}, year={2016}, pages={65} }