Статті в журналах: "Core parameters"

1

Lothe, J., and J. P. Hirth. "Dislocation core parameters." physica status solidi (b) 242, no. 4 (March 2005): 836–41. http://dx.doi.org/10.1002/pssb.200402114.

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2

Baumgardt, Holger, Douglas C. Heggie, Piet Hut, and Junichiro Makino. "Parameters of core collapse." Monthly Notices of the Royal Astronomical Society 341, no. 1 (May 2003): 247–50. http://dx.doi.org/10.1046/j.1365-8711.2003.06407.x.

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3

Schoeck, Gunther. "Atomic dislocation core parameters." physica status solidi (b) 247, no. 2 (December 10, 2009): 265–68. http://dx.doi.org/10.1002/pssb.200945379.

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4

Luthfi, Wahid, and Surian Pinem. "VALIDATION OF SRAC CODE SYSTEM FOR NEUTRONIC PARAMETERS CALCULATION OF THE PWR MOX/UO2 CORE BENCHMARK." Urania : Jurnal Ilmiah Daur Bahan Bakar Nuklir 27, no. 1 (February 28, 2021): 47. http://dx.doi.org/10.17146/urania.2021.27.1.6238.

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VALIDATION OF SRAC CODE SYSTEM FOR NEUTRONIC PARAMETERS CALCULATION OF THE PWR MOX/UO2 CORE BENCHMARK. Determination of neutronic parameter value is an important part in determining reactor safety, so accurate calculation results can be obtained. This study is focused on the validation of SRAC code system in the calculation of neutronic parameters value of a PWR (Pressurized Water Reactor) reactor core. MOX/UO2 Core Benchmark was choosed because it is used by several researchers as a reference core for code validation in the determination of neutronic parameters of a reactor core. The neutronic parameters calculated include critical boron concentration, delayed neutron fraction, and Power Peaking Factor (PPF) and its distribution in axial and radial directions. When compared with reference data, the calculation results of the critical boron concentration value show that there is a difference of 22.5 ppm on SRAC code system. Meanwhile, differences in power per fuel element (assembly power error) value of power-weighted error (PWE) and error-weighted error (EWE) is 2.93% and 3.94%, respectively. Maximum difference between PPF value in axial direction with reference reaches a value of 4.57%. SRAC calculation results also show consistency with the calculation results of other program packages or code. Results of this study indicate that SRAC code system is still quite accurate for the calculation of neutronic parameters of PWR reactor core benchmark. Therefore, SRAC code system can be used to calculate neutronic parameters of PWR reactor core, especially when using MOX (mixed oxide) fuel.Keywords: Neutronic parameter, critical boron concentration, power peaking factor, SRAC code system.

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5

Mitkov, Svetlomir, Ivan Spasov, and Nikola Kolev. "Thermal-hydraulic analysis of a VVER-1000 core in MSLB conditions." E3S Web of Conferences 327 (2021): 01013. http://dx.doi.org/10.1051/e3sconf/202132701013.

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The objective of this paper is to analyze the ability of a VVER-1000 core and its control system to cope with a hypothetical main steam line break (MSLB) accident in case of multiple equipment failures. The study involves the use of advanced 3D core calculation models benchmarked and validated for reactivity accidents in preceding studies. A MSLB core boundary condition problem is solved on a coarse (nodal) mesh with the coupled COBAYA/CTF neutronic/thermal hydraulic codes. The core thermal-hydraulic boundary conditions are obtained from a preceding full-plant MSLB simulation. The assessment of the core safety parameters is supplemented by a fine-mesh (sub-channel) thermal-hydraulic analysis of the hottest assemblies with the CTF code using information from the 3D nodal COBAYA/CTF calculations. Thirteen variants of a pessimistic MSLB scenario are considered, each of them assuming a number of equipment failures aggravated by eight control rods stuck out of the core after scram at different locations in the overcooled sector. The results (within the limitations of the adopted modeling assumptions) show that the core safety parameters do not exceed the safety limits in the simulated aggravated reactivity accidents.

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6

Valentino, E. Di, T. Brinckmann, M. Gerbino, V. Poulin, F. R. Bouchet, J. Lesgourgues, A. Melchiorri, et al. "Exploring cosmic origins with CORE: Cosmological parameters." Journal of Cosmology and Astroparticle Physics 2018, no. 04 (April 5, 2018): 017. http://dx.doi.org/10.1088/1475-7516/2018/04/017.

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7

Novak, Franc, Peter Mrak, and Anton Biasizzo. "Measuring Static Parameters of Embedded ADC Core." Journal of Electrical Engineering 62, no. 2 (March 1, 2011): 80–86. http://dx.doi.org/10.2478/v10187-011-0013-3.

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Measuring Static Parameters of Embedded ADC CoreThe paper presents the results of a feasibility study of measuring static parameters of ADC cores embedded in a System-on-Chip. Histogram based technique is employed because it is suitable for built-in self-test. While the theoretical background of the technique has been covered by numerous papers, less attention has been given to implementations in practice. Our goal was the implementation of histogram test in a IEEE Std 1500 wrapper. Two different solutions pursuing either minimal test time or minimal hardware overhead are described. The impact of MOS switches at ADC input on the performed measurements was considered.

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8

Zografos, George C., Flora Zagouri, Theodoros N. Sergentanis, Afrodite Nonni, Nikolaos Lymperopoulos, and Effstratios Patsouris. "What parameters affect pain in core biopsy?" European Radiology 18, no. 6 (February 16, 2008): 1144–45. http://dx.doi.org/10.1007/s00330-008-0879-z.

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9

Turinsky, Paul, Aaron Graham, Hisham Sarsour, and Benjamin Collins. "GENERATION OF NODAL CORE SIMULATOR UTILIZING VERA." EPJ Web of Conferences 247 (2021): 02018. http://dx.doi.org/10.1051/epjconf/202124702018.

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Nuclear core simulators based upon few-group nodal diffusion method currently are widely used to predict light water reactor core behavior. Nodal parameters’ input, e.g. cross-sections, discontinuity factors, and pin form factors, are typically generated utilizing lattice physics codes. In doing so, a number of approximations are introduced related to using zero current boundary conditions, 2-D radial geometry, and uniform thermal conditions in coolant and fuel. Usage of full core models with prediction fidelity typical of lattice physics to predict nodal parameters would eliminate these approximations. The VERA code can serve as such a full core model and was so utilized in this work. Via subsequent processing of VERA predictions, for a range of state points, nodal parameters and their functionalization in terms of coolant density, fuel temperature, and soluble poison concentration, were obtained and input to the NESTLE nodal code. By processing VERA predictions using consistent nodal methodologies as used in NESTLE, when using nodal parameters after functionalization based upon All-Rods-Out (ARO) VERA state points, the maximum reactivity and pin power differences between VERA and NESTLE were 2 pcm and 0.003 for ARO core simulations. For rodded core simulations, these maximum differences grew to 58 pcm and 0.04. Increases in differences were determined to be attributed to usage of unrodded nodal parameters generated using the VERA ARO state points whether the core is partially rodded or not, consistent with lattice physics practice. Obtaining unrodded nodal parameters using the VERA rodded state points reduced maximum differences to 2 pcm and 0.003 in pin powers.

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10

Ashoub, N., and E. Amin. "Neutronic studies for the second Egyptian research reactor ET-RR-2." Kerntechnik 66, no. 4 (August 1, 2001): 177–81. http://dx.doi.org/10.1515/kern-2001-0077.

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Abstract The start up physics studies SPS of the Second Egyptian Research Reactor is presented in this work. The SPS consists of the approach to criticality, the power and flux distribution of the first critical core, criticality, power and flux distribution of the working core. The working core is the beryllium-reflected core with cobalt loaded for irradiation. Some of the neutronic parameters are determined, these parameters are the power peaking factor, power distribution, the excess reactivity for both the water and beryllium reflector cores, the core excess reactivity with the cobalt loaded, the reactivity worth of the cobalt irradiation box. Flux distribution for one fast, three eipthermal and one thermal energy group are also determined. All the above neutronic parameters are calculated by using the lattice cell code WIMSD4 and the two dimensional diffusion code DIXY2.

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11

Li, Yan, Peter A. A. F. Wouters, Paul Wagenaars, Yunpeng Liu, Tao Zhao, and Zhuoran Song. "Core asymmetry influence on transmission line parameters of three‐core power cables." IET Science, Measurement & Technology 15, no. 5 (March 3, 2021): 469–77. http://dx.doi.org/10.1049/smt2.12047.

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12

Xu, Fei, and Min Ge Duan. "The Sensitivity of the Foam-Core Parameters under Impact Loading." Key Engineering Materials 525-526 (November 2012): 289–92. http://dx.doi.org/10.4028/www.scientific.net/kem.525-526.289.

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This study presents the numerical investigation of the low-velocity impact for the foam-cored sandwich composites. Firstly, the proposed FEA model is validated by comparing the results between simulation and test. The user subroutine VUMAT and the crushable foam model are chosen to describe the damage of the face sheets and the characteristics of the foam material, respectively. The detailed damage process of the sheets and the foam is clearly shown. The sensitivity of seven parameters related to foam-core material are studied. It is shown that the yield strength, the fracture strain and the fracture displacement have significant effects on the impact-resistance of the foam-cored sandwich composites.

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13

Reis, Patrícia A. L., Antonella L. Costa, Claubia Pereira, Maria Auxiliadora F. Veloso, and Amir Z. Mesquita. "Simulation of a TRIGA Reactor Core Blockage Using RELAP5 Code." Science and Technology of Nuclear Installations 2015 (2015): 1–10. http://dx.doi.org/10.1155/2015/354163.

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Cases of core coolant flow blockage transient have been simulated and analysed for the TRIGA IPR-R1 research reactor using the RELAP5-MOD3.3 code. The transients are related to partial and to total obstruction of the core coolant channels. The reactor behaviour after the loss of flow was analysed as well as the changes in the coolant and fuel temperatures. The behaviour of the thermal hydraulic parameters from the transient simulations was analysed. For a partial blockage, it was observed that the reactor reaches a new steady state operation with new values for the thermal hydraulic parameters. The total core blockage brings the reactor to an abnormal operation causing increase in core temperature.

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14

Oyno, Lars, B. G. Tjetland, K. H. Esbensen, Rune Solberg, Aase Scheie, and Tore Larsen. "Prediction of Petrophysical Parameters Based on Digital Video Core Images." SPE Reservoir Evaluation & Engineering 1, no. 01 (February 1, 1998): 82–87. http://dx.doi.org/10.2118/36853-pa.

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Summary Core-slab photography is a common way to document geological information from cores. Past practice has been to photograph core slabs with ordinary cameras that produce paper photographs. The presented method retrieves petrophysical properties from high-resolution digital video core images. The procedures described in this work are based on video images (standard RIO/B camera) of cores taken with a digital recording system. The system is able to record in both visible and UV light at different illumination angles, store images, compress/decompress images, and display one or several images as a continuous long core. The seamless core image is marked with depth scale and can be scrolled, scaled, and zoomed. Facilities for correlation with other related data, such as wireline logs, discrete core data, and microscopy images, are also included in the system. We used homogenous dry core plugs from three North Sea oil fields in this work. We recorded images of plug surface, together with conventional core-analysis data (i.e., porosity, gas permeability, average grain size, and mineralogy). The new method is based on processed digital images: light/shadow patterns are obtained by use of asymmetric, low-angle illumination in the green channel. Texture spectra of the rock material are obtained by dedicated image-analytical processing of these gray-scale images and by detecting textural features by use of a unique set of specially designed texture filters. We then calibrate these spectra with respect to measured petrophysical parameters by use of multivariate calibration [partial least squares (PLS)-regression]. Multivariate calibration is based on a set of representative training images, selected to span representative ranges of the intensive petrophysical parameters being modeled. On the basis of this calibration model, similar gray-level video images from new, unknown core sections (with geologically similar facies) are used to estimate properties of the core material by PLS-prediction. In this study it has been possible to model porosity, gas permeability, and average grain size (ORZ) of different formations with a relatively high accuracy and precision. PLS-modeling/-prediction is a strict empirical calibration procedure. The present method is critically dependent upon a thorough, geologically well-documented training data set. Results show that the method is capable of predicting a continuous log of these three petrophysical parameters based on core images calibrated against a set of routine laboratory core-analysis data taken at discrete intervals for a particular formation. The advantages of the new method are rapid and cost-efficient methods for prediction of petrophysical parameters, particularly from slim cores, and improved integration of geological records with wireline data. The method is proposed to be included in future routine laboratory core analysis studies because of its low cost and ability to predict values continuously along the core. Introduction In many cases where core material is available from a potential hydrocarbon reservoir, it is possible to perform conventional laboratory core analysis on selected zones or at regular intervals. These measurements are commonly used as input in numerical simulations predicting recovery from the field. The results are also commonly used for net pay calculations to provide a reserves estimate.1–4 Usually, conventional core plugs are taken at regular intervals (every 30 cm or every meter) in the reservoir zone. Core-analysis plugs are often neglected below the oil/water contact (OWC), sometimes also in other parts of the reservoir for various reasons. Core photography has been used for decades to document the geology in the reservoir for later study. The photographs are usually printed on paper with a few core lengths in each photograph. Obtaining a complete picture of the reservoir geology and petrophysics from the core photographs involves extensive leafing through numerous pages of core photographs. Also, paper photographs do not offer the possibility to perform image analysis. Advances in digital storage and image analysis, together with decreasing costs of computers, have now allowed the use of digital storage of core information.5–8 The work described in this article makes exclusive use of digitally recorded imagery. Core images are taken continuously along the slabbed core. Software automatically combines the core images into a seamless, continuous core image of the complete length of the core's interval. This opens the door to easy access to image analysis. In contrast with the routine core-analysis measurements, the present digital video images provide continuous information regarding the texture of the core material. If these images also could be used to extract petrophysical information, they could offer parameter values continuously along the entire cored material. Because reservoir material differs widely from field to field and also between wells, we expected some initial experimentation with optimal recording parameters as well as the geological calibration base to be necessary to tune a new type of image correlation model. Consider an image of core material, say sandstone, where each grain can be seen at an appropriate resolution; it is not difficult to accept that image analysis should be able to extract grain-size (and grain-size distribution) information pertaining to the material in the field of view. Grains can be seen down almost throughout the fine range of the sandstone grain size. Moreover, when applying different data analytical techniques to postprocess, earlier-derived texture spectra, it became clear that even other petrophysical parameters like porosity and permeability could indeed also be predicted. Multivariate calibration,18,19 to be explained further later, is carried out from a number of calibration samples where the desired petrophysical parameters are known (from traditional methods). The camera field of view was maintained constant, and an analysis area large enough to be representative for all types of material in the present study was determined by initial sensitivity analysis. The advantage of the presented method is that petrophysical parameters now can be predicted directly from identical video imagery on samples which then, of course, need not be measured in the laboratory. This approach can even be augmented so as also to produce results from layered zones, where routine core-analysis results are difficult to obtain. It can also provide results where routine core-analysis results are doubtful, for example, in unconsolidated cores. Last, it provides continuous petrophysical estimates from a core at a detail and at significantly lowered cost, which is both impractical and uneconomical to achieve with conventional core analysis.

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15

Kryshchuk, R. S. "INFLUENCE OF WINDING ENDS ON THE PARAMETERS OF PULSE INDUCTOR WITH U-SHAPED CORE." Tekhnichna Elektrodynamika 2020, no. 6 (October 21, 2020): 69–76. http://dx.doi.org/10.15407/techned2020.06.069.

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It is known from the scientific literature that magnetic pulse processing of electrically conductive non-magnetic sheet materials helps to reduce residual stresses, especially in welded joints. This is due to magnetoplastic and electroplastic effects. To create such effects in non-magnetic electrically conductive materials with welded joints, an inductor with pulsed magnetic field, U-shaped magnetic circuit and hollow conductor for possibility of active cooling of the winding is proposed. Such inductor allows inducing high-density pulsed currents in electrically conductive non-magnetic sheet materials with welded joints. It studies the parameters of the inductor - active resistance and inductance in the frequency-domain mode. The parameters calculated in two-dimensional and three-dimensional models are compared. The electromagnetic field is calculated using Maxwell equations and finite element method. Parameters of an ends of winding are determined by the difference in the parameters of the three-dimensional and two-dimensional models of the induction system. Resistance is calculated separately in the groove`s part of the winding, the outer part and on the frontal parts. The parameters of the induction system with a ferromagnetic core and non-magnetic thin-sheet alloy AMg6 are calculated for various values of complex amplitude of current in winding. Additionally, the parameters are calculated both without the magnetic core and without the non-magnetic metal. The quantitative comparison of the parameters of the three-dimensional model with the two-dimensional one is performed. The active resistance and inductance of end parts of the inductor are investigated by well-known analytical expressions from handbooks of electric machines. References 11, figures 3, tables 6.

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16

Wagenaars, P., P. A. F. Wouters, P. J. M. Van Der Wielen, and E. Steennis. "Approximation of transmission line parameters of single-core and three-core XLPE cables." IEEE Transactions on Dielectrics and Electrical Insulation 17, no. 1 (February 2010): 106–15. http://dx.doi.org/10.1109/tdei.2010.5412008.

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17

Xu, Yubin. "Optimizing the Neutronic Parameters for VVER-1200 Reactor Core Using WIMS-ANLS Code." Global Nuclear Safety 13, no. 1 (March 2018): 87–95. http://dx.doi.org/10.26583/gns-2018-01-09.

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18

Kuntoro, Iman, Surian Pinem, and Tagor Malem Sembiring. "VALIDATION OF PWR-FUEL CODE FOR STATIC PARAMETERS IN THE LWR CORE BENCHMARK." JURNAL TEKNOLOGI REAKTOR NUKLIR TRI DASA MEGA 20, no. 3 (October 30, 2018): 111. http://dx.doi.org/10.17146/tdm.2018.20.3.4650.

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The PWR-FUEL code is a multi dimensional, multi group diffusion code with nodal and finite difference methods. The code will be used to calculate the fuel management of PWR reactor core. The result depends on the accuracy of the codes in producing the core effective multiplication factor and power density distribution. The objective of this research is to validate the PWR-FUEL code for those cases. The validation are carried out by benchmarking cores of IAEA-2D, KOERBERG-2D and BIBLIS-2D. The all three cases have different characteristics, thus it will result in a good accuracy benchmarking. The calculation results of effective multiplication factor have a maximum difference of 0.014 %, which is greater than the reference values. For the power peaking factor, the maximum deviation is 1.75 % as compared to the reference values. Those results show that the accuracy of PWR-FUEL in calculating the static parameter of PWR reactor benchmarks are very satisfactory.Keywords: Validation, PWR-FUEL code, static parameter. VALIDASI PROGRAM PWR-FUEL UNTUK PARAMETER STATIK PADA TERAS BENCHMARK LWR. Program PWR-FUEL adalah program difusi multi-dimensi, multi-kelompok dengan metode nodal dan metode beda hingga. Program ini akan digunakan untuk menghitung manajemen bahan bakar teras reaktor PWR. Akurasi manajemen bahan bakar teras PWR tergantung pada akurasi program dalam memprediksi faktor multiplikasi efektif teras dan distribusi rapat daya. Untuk itu dilakukan validasi program PWR-FUEL sebagai tujuan dalam penelitian ini. Validasi PWR-FUEL dilakukan menggunakan teras benchmark IAEA-2D, KOERBERG-2D dan BIBLIS-2D. Ketiga kasus ini mempunyai karaktristik yang berbeda sehingga akan memberikan hasil benchmark yang akurat. Hasil perhitungan faktor multiplikasi efektif terdapat perbedaan maksimum adalah 0,014 % lebih besar dari referensi. Sedangkan untuk perhitungan faktor puncak daya, terdapat perbedaan maksimum 1,75 % dibanding harga referensi. Hasil perhitungan menunjukkan bahwa akurasi paket program PWR-FUEL dalam menghitung parameter statik benchmark reaktor PWR menunjukkan hasil yang sangat memuaskan.Kata kunci: Validasi, program PWR-FUEL, parameter statik

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19

Gubanov, V. S. "New estimates of retrograde free core nutation parameters." Astronomy Letters 36, no. 6 (June 2010): 444–51. http://dx.doi.org/10.1134/s1063773710060083.

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20

Irving, Jessica C. E., Sanne Cottaar, and Vedran Lekić. "Seismically determined elastic parameters for Earth’s outer core." Science Advances 4, no. 6 (June 2018): eaar2538. http://dx.doi.org/10.1126/sciadv.aar2538.

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21

Jie, Sun, Zhao Yang, Sun Zhaowei, and An Nan. "Researches on optimization of micro‐core attitude parameters." Aircraft Engineering and Aerospace Technology 78, no. 5 (September 2006): 371–77. http://dx.doi.org/10.1108/00022660610685521.

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22

Luthfi, Wahid, and Surian Pinem. "CALCULATION OF 2-DIMENSIONAL PWR MOX/UO2 CORE BENCHMARK OECD NEA 6048 WITH SRAC CODE." JURNAL TEKNOLOGI REAKTOR NUKLIR TRI DASA MEGA 22, no. 3 (September 30, 2020): 89. http://dx.doi.org/10.17146/tdm.2020.22.3.5955.

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The mixed uranium-plutonium oxide fuel (MOX/UO2) is an interesting fuel for future power reactors. This is due to the large amount of plutonium that can be processed from spent fuel of nuclear plants or from plutonium weapons. MOX/UO2 fuel is very flexible to be applied in thermal reactors such as PWR and it is more economical than UO2 fuel. However, due to the different nature of neutron interactions of MOX in PWR, it will change the reactor core design parameters and also its safety characteristic. The purpose of this study is to determine the accuracy of SRAC2006 code system in generation of cross-sections and calculation of reactor core design parameters such as criticality, reactivity of control rods and radial power distribution. In this study, PWR MOX/UO2 Core Transient Benchmark is used to verify the code that models a MOX/UO2 fueled core. SRAC-CITATION result is different from DeCART by 0.339% from. SRAC-CITATION result of single rod worth in All Rods Out (ARO) conditions are quite good with a maximum difference of 6.34% compared to BARS code and 4.74% compared to PARCS code. In All Rods In (ARI) condition, SRAC-CITATION results compared to the PARCS code is quite good where the maximum difference is 9.72%, but compared to BARS code, it spikes up to 33.24% at maximum difference. In the other case, overall radial power density results are quite good compared to the reference. Its maximum deviation from DeCART code is 5.325% in ARO condition and 6.234% in ARI condition. Based on the results of these calculations, SRAC code system can be used to generate cross-section and to calculate some neutronic parameters. Hence, it can be used to evaluate the neutronic parameters of the MOX/UO2 PWR core design.Keywords: MOX/UO2 fuel, Criticality, Power peaking factor, SRAC2006

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23

Trontl, Krešimir, Dubravko Pevec, and Tomislav Šmuc. "Machine Learning of the Reactor Core Loading Pattern Critical Parameters." Science and Technology of Nuclear Installations 2008 (2008): 1–6. http://dx.doi.org/10.1155/2008/695153.

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The usual approach to loading pattern optimization involves high degree of engineering judgment, a set of heuristic rules, an optimization algorithm, and a computer code used for evaluating proposed loading patterns. The speed of the optimization process is highly dependent on the computer code used for the evaluation. In this paper, we investigate the applicability of a machine learning model which could be used for fast loading pattern evaluation. We employ a recently introduced machine learning technique, support vector regression (SVR), which is a data driven, kernel based, nonlinear modeling paradigm, in which model parameters are automatically determined by solving a quadratic optimization problem. The main objective of the work reported in this paper was to evaluate the possibility of applying SVR method for reactor core loading pattern modeling. We illustrate the performance of the solution and discuss its applicability, that is, complexity, speed, and accuracy.

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24

Bedez Ute, T., and H. Kadoglu. "The effects of core material parameters on the mechanical properties of double core and single core spun yarns." IOP Conference Series: Materials Science and Engineering 459 (December 7, 2018): 012032. http://dx.doi.org/10.1088/1757-899x/459/1/012032.

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25

Razak, M. F. Abdul, Abdul Ghalib, Abdullah Abdullah, and M. A. H. Ramli. "Prediction of Flux Core Arc Welding (FCAW) Bead Geometry and Welding Parameters for 1G Position." International Journal of Materials, Mechanics and Manufacturing 5, no. 1 (February 2017): 55–58. http://dx.doi.org/10.18178/ijmmm.2017.5.1.289.

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26

Reda, Sonia, Ibrahim Gomaa, Ibrahim Bashter, and Esmat Amin. "Effect of MOX fuel and the ENDF/B-VIII on the AP1000 neutronic parameters calculations by using MCNP6." Nuclear Technology and Radiation Protection 34, no. 4 (2019): 325–35. http://dx.doi.org/10.2298/ntrp190705002r.

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The present work studies the effect of introducing MOX fuel on Westinghouse AP1000 neutronic parameters. The neutronic calculations were performed by using the MCNP6 code with the ENDF/B-VII.1 library and the new release of the ENDF/B-VIII, the AP1000 core with three 235U enrichment zones (2.35 %, 3.40 %, and 4.45 %). The obtained results showed that the simulated model for the AP1000 core satisfies the optimization criteria as a Westing- house reference. The results which included: effective multiplication factor, keff, delayed neutron fraction, beff, excess reactivity, rex, shutdown margin, temperature reactivity coefficients, whole core depletion, neutron flux, power peaking factor and core power density, were calculated and compared with the available published results. The keff in the cold zero power was found to be 1.20495 and 1.20247 with the ENDF/B-VII.1 and the ENDF/B-VIII libraries, respectively, which matches the value of 1.205 presented in the AP1000 Design Control Document for the UO2 fuel core. On the other hand, keff in the cold zero power was found to be 1.19988 and 1.19860 for MOX core with the ENDF/B-VII.1 and the ENDF/B-VIII libraries, respectively, which show good reception and confirm the safety of the design and efficient modeling of AP1000 reactor core.

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27

Dimitrov, Dobromir, and Sergey Belousov. "Comparison of Neutron-Physical Parameters of EPR and WWER-1500 using MCNP Computer Code." IOP Conference Series: Earth and Environmental Science 1128, no. 1 (January 1, 2023): 012023. http://dx.doi.org/10.1088/1755-1315/1128/1/012023.

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Abstract Three-dimensional calculations of the neutron-physical parameters were performed with the MCNP computer code for two models of a reactor core. The purpose was to determine the coefficient of reproduction of neutrons keff in each of the defined cases, as well as to qualitatively illustrate the neutron flux in axial and radial directions of the reactor core. A generalized analysis of the obtained results is performed, and it can be said that the prepared models, being relatively simple, meet the goal of this paper, namely presenting the basic principles of performing criticality calculations with the MCNP computer code. All calculations for this paper were performed with MCNP5, ver. 1.4. In the present paper, two active core models are considered – one for the EPR reactor and the other for the WWER-1500. Both projects are categorized as Generation 3 nuclear reactors. The following components of the core are included in both models: fuel elements, control rods and coolant. The fuel elements are presented as solid uranium dioxide cylinders coated with zirconium alloy. The fuel elements are grouped in fuel assemblies, in the case of the EPR reactor the fuel elements are arranged in a square grid, and in the case of the WWER-1500 reactor – in a triangular grid (hexagonal geometry). The limits of both models in the radial-azimuthal direction coincide with the inner diameter of the reactor vessel, and in the axial direction the limit is 56 cm in both directions from the end of the fuel elements. The calculations performed in this paper do not aim to quantify the distribution of neutron flux in the core, nor to find with great accuracy the coefficient of reproduction of neutrons keff at different stages of the reactor campaign. The calculations are made in order to verify the accuracy of the compiled input files. A criterion for this could be the demonstration of basic neutron-physical parameters, such as an increase in the value of keff with increasing the fuel enrichment and qualitative illustration of the change in the distribution of the neutron flux when introducing control rods in the core.

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28

Vandermeersch, Elias, Maxence Maillot, Pierre Tamagno, Jean Tommasi, and Cyrille De Saint Jean. "Two examples of recent advances in sensitivity calculations." EPJ Nuclear Sciences & Technologies 7 (2021): 13. http://dx.doi.org/10.1051/epjn/2021012.

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This article reviews two recently established methods to compute sensitivities of some core parameters to basic nuclear data. First, perturbation theory offers an efficient way to compute sensitivities to nuclear parameters in continuous energy transport simulations: making use of the Iterated Fission Probability method, and by coupling the Monte Carlo code TRIPOLI-4® to the nuclear evaluation code CONRAD, we were able to compute the sensitivity of core reactivity to nuclear parameters for simple ICSBEP benchmarks. Second, using a multipoint description of a nuclear system and deterministic transport calculations the sensitivity of the state eigenvector of the system to multigroup nuclear data is computed using simple and fast partial importance calculations.

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29

Webbink, R. F. "Structure Parameters of Galactic Globular Clusters." Symposium - International Astronomical Union 113 (1985): 541–77. http://dx.doi.org/10.1017/s0074180900147771.

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Observed and derived structure parameters are tabulated for 154 galactic globular clusters, 7 dwarf spheroidal satellites of the Galaxy, and 6 globular clusters in the Fornax dwarf spheroidal. Observational parameters listed include equatorial coordinates, apparent level of the horizontal branch, reddening, subgiant branch color at the horizontal branch level, limiting and core angular radii, integrated magnitudes, and central surface brightnesses. Derived parameters include galactic coordinates, heliocentric and galactocentric distance, metallicity, limiting and core radii, central relaxation time scale, central mass density, central velocity dispersion, and central escape velocity.

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30

Shi, Hao, Qi Cai, and Yuqing Chen. "Sensitivity Evaluation of AP1000 Nuclear Power Plant Best Estimation Model." Science and Technology of Nuclear Installations 2017 (2017): 1–13. http://dx.doi.org/10.1155/2017/9304520.

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The best estimation process of AP1000 Nuclear Power Plant (NPP) requires proper selections of parameters and models so as to obtain the most accurate results compared with the actual design parameters. Therefore, it is necessary to identify and evaluate the influences of these parameters and modeling approaches quantitatively and qualitatively. Based on the best estimate thermal-hydraulic system code RELAP5/MOD3.2, sensitivity analysis has been performed on core partition methods, parameters, and model selections in AP1000 Nuclear Power Plant, like the core channel number, pressurizer node number, feedwater temperature, and so forth. The results show that core channel number, core channel node number, and the pressurizer node number have apparent influences on the coolant temperature variation and pressure drop through the reactor. The feedwater temperature is a sensitive factor to the Steam Generator (SG) outlet temperature and the Steam Generator outlet pressure. In addition, the cross-flow model nearly has no effects on the coolant temperature variation and pressure drop in the reactor, in both the steady state and the loss of power transient. Furthermore, some fittest parameters with which the most accurate results could be obtained have been put forward for the nuclear system simulation.

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31

Khakim, Azizul, T. Yokoyama, and Hisashi Ninokata. "Study on Void Reactivity of Liquid Metal Fast Breeder Reactor." Indonesian Journal of Physics 19, no. 1 (November 3, 2016): 13–17. http://dx.doi.org/10.5614/itb.ijp.2008.19.1.2.

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Liquid Metal Fast Breeder Reactor (LMFBR) usually has positive void reactivity which is not favorable to the reactor safety. Therefore, the void generation should be avoided during normal reactor operation. Design of reactor core should consider the parameters that influence the void reactivity in order to minimize it, should void be generated during an accident. In this study, several parameters have been evaluated to observe their contribution to the overall void reactivity, such as the build-up of minor actinides (MAs), different inner and outer core height, heterogeneous core configuration, upper plenum, upper axial blanket, voiding in the inner and outer core and the effect of P/D. The study is performed in 3-D heterogeneous geometry using Monte Carlo Method of MVP Code with JENDL-3.3

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32

Durchholz, Holger, Björn Salomonsson, Philipp Moroder, Simon Lambert, Richard Page, Laurent Audigé, John Sperling, and Hans-Kaspar Schwyzer. "Core Set of Radiographic Parameters for Shoulder Arthroplasty Monitoring." JBJS Open Access 4, no. 4 (2019): e0025. http://dx.doi.org/10.2106/jbjs.oa.19.00025.

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33

Pacher, G. W., H. D. Pacher, A. S. Kukushkin, G. Janeschitz, and G. Pereverzev. "Core plasma operation consistent with SOL parameters in ITER." Nuclear Fusion 43, no. 3 (February 25, 2003): 188–95. http://dx.doi.org/10.1088/0029-5515/43/3/304.

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34

Ossenkopf, V., C. Trojan, and J. Stutzki. "Massive core parameters from spatially unresolved multi-line observations." Astronomy & Astrophysics 378, no. 2 (November 2001): 608–26. http://dx.doi.org/10.1051/0004-6361:20010893.

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35

Szames, Esteban, and Daniele Tomatis. "A review of history parameters in PWR core analysis." Nuclear Engineering and Design 347 (June 2019): 158–74. http://dx.doi.org/10.1016/j.nucengdes.2019.03.012.

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36

Hinderer, J., J. P. Boy, P. Gegout, P. Defraigne, F. Roosbeek, and V. Dehant. "Are the free core nutation parameters variable in time?" Physics of the Earth and Planetary Interiors 117, no. 1-4 (January 2000): 37–49. http://dx.doi.org/10.1016/s0031-9201(99)00085-0.

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37

Geslin, Pierre-Antoine, and David Rodney. "Investigation of partial dislocations fluctuations yields dislocation core parameters." Modelling and Simulation in Materials Science and Engineering 28, no. 5 (May 15, 2020): 055006. http://dx.doi.org/10.1088/1361-651x/ab8a96.

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38

Lambert, S. B., and V. Dehant. "The Earth's core parameters as seen by the VLBI." Astronomy & Astrophysics 469, no. 2 (April 24, 2007): 777–81. http://dx.doi.org/10.1051/0004-6361:20077392.

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39

Pereira, Diana, Jörg Bierlich, Jens Kobelke, and Marta S. Ferreira. "Hollow square core fiber sensor for physical parameters measurement." Journal of Physics: Conference Series 2407, no. 1 (December 1, 2022): 012034. http://dx.doi.org/10.1088/1742-6596/2407/1/012034.

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Abstract The measurement of physical parameters is important in many current applications, since they often rely on these measurands to operate with the due quality and the necessary safety. In this work, a simple and robust optical fiber sensor based on an antiresonant hollow square core fiber (HSCF) is proposed to measure simultaneously temperature, strain, and curvature. The proposed sensor was designed in a transmission configuration where a segment of HSCF, with a 10 mm length, was spliced between two single mode fibers. In this sensor, a cladding modal interference (CMI) and a Mach-Zehnder interference (MZI) are enhanced along with the antiresonance (AR) guidance. All the present mechanisms exhibit different responses towards the physical parameters. For the temperature, sensitivities of 32.8 pm/°C, 18.9 pm/°C, and 15.7 pm/°C were respectively attained for the MZI, AR, and CMI. As for the strain, sensitivities of 0.45 pm/με, -0.93 pm/με, and -2.72 pm/με were acquired for the MZI, AR and CMI respectively. Meanwhile, for the curvature measurements, two regions of analysis were considered. In the first region (0 m−1 - 0.7 m−1) sensitivities of 0.033 nm/m−1, -0.27 nm/m−1, and -2.21 nm/m−1 were achieved, whilst for the second region (0.7 m−1 - 1.5 m−1) sensitivities of 0.067 nm/m−1, -0.63 nm/m−1, and -0.49 nm/m−1 were acquired for the MZI, AR and CMI, respectively.

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40

Kromar, Marjan, and Bojan Kurinčič. "Validation of the CORD-2 System for the NPP Krško Nuclear Core Design Calculations." Journal of Energy - Energija 65, no. 1-2 (June 28, 2022): 105–15. http://dx.doi.org/10.37798/2016651-2134.

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The CORD-2 package intended for core design calculations of PWRs has been recently updated with some improved models. Since the modifications could substantially influence the obtained results, a technical validation process is required. This paper presents comparison of some calculated and measured parameters of the NPP Krško core needed to qualify the package. Critical boron concentrations at hot full power for selected cycle burnup points and several parameters obtained during the start-up testing at the beginning of each cycle (hot zero power critical concentration, isothermal temperature coefficient and rods worth) for all 27 finished cycles of operation are considered. In addition, assembly-wise power distribution for some selected cycles is checked. Comparison has shown very good agreement of the CORD-2 calculated values with the selected measured parameter of the NPP Krško core.

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41

WenChang Tsai. "Effects of Core Materials and Operating Parameters on Core Losses in a Brushless DC Motor." International Journal of Engineering and Industries 2, no. 1 (March 31, 2011): 51–61. http://dx.doi.org/10.4156/ijei.vol2.issue1.7.

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42

Jiang Wenxiao, 蒋文晓, 谭晓玲 Tan Xiaoling, and 周骏 Zhou Jun. "Changes of propagation characteristics with core parameters in kagome-structured hollow-core photonic crystal fibers." High Power Laser and Particle Beams 23, no. 10 (2011): 2578–82. http://dx.doi.org/10.3788/hplpb20112310.2578.

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43

Manzur, Tanvir, Ayatullah Khomeni, Bayezid Baten, and Khandaker M. Anwar Hossain. "Investigating significance of various parameters affecting capacity of core drilled columns for safe core extraction." Engineering Structures 200 (December 2019): 109722. http://dx.doi.org/10.1016/j.engstruct.2019.109722.

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44

Gosiewski, Zdzisław, and Mirosław Kondratiuk. "Selection of Coils Parameters in Magnetic Launchers." Solid State Phenomena 147-149 (January 2009): 438–43. http://dx.doi.org/10.4028/www.scientific.net/ssp.147-149.438.

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This paper describes the process of a coil launcher parameters selection. Objective function Θ was defined and crucial variables were sought. The electro-mechanical system consisting of a copper coil and a ferromagnetic core was designed. Displacement of the core was computed. The magnetic force and coil inductance were calculated in many core position in relation to solenoid. Simulations were done by means of Finite Elements Method (FEM). The model parameters were being changed and the best system geometry was sought. In order to achieve better legibility, the research results were shown in the graphs. Selection process turned out to be very complex. In order to determine the best device parameters, the currents thermal effects should be taken into consideration. As the final conclusion some constructional conceptions of the magnetic launcher were proposed. The research will be continued to improve the coil launcher optimization process. The aim of future investigations is to achieve greater magnetic force and lower inductance of the electro-mechanical system.

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45

Afremov, Leonid, and Artur Elovskii. "Magnetic Condition Flat Core/Shell Nanoparticles." Applied Mechanics and Materials 752-753 (April 2015): 238–42. http://dx.doi.org/10.4028/www.scientific.net/amm.752-753.238.

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In terms two-phase nanoparticles model, dependence equilibrium position of magnetic moments of parameters size and elongation nanoparticles core is investigated. Phase diagrams of magnetic states were shown and determine geometrical parameters core, in equilibrium states.

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46

Brage, Tomas, David S. Leckrone, and Charlotte Froese Fischer. "Core-valence and core-core correlation effects on hyperfine-structure parameters and oscillator strengths in Tl ii and Tl iii." Physical Review A 53, no. 1 (January 1, 1996): 192–200. http://dx.doi.org/10.1103/physreva.53.192.

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47

Ali, I., U. Wasenmüller, and N. Wehn. "A code-aided synchronization IP core for iterative channel decoders." Advances in Radio Science 11 (July 4, 2013): 137–42. http://dx.doi.org/10.5194/ars-11-137-2013.

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Abstract. Synchronization and channel decoding are integral parts of each receiver in wireless communication systems. The task of synchronization is the estimation of the general unknown parameters of phase, frequency and timing offset as well as correction of the received symbol sequence according to the estimated parameters. The synchronized symbol sequence serves as input for the channel decoder. Advanced channel decoders are able to operate at very low signal-to-noise ratios (SNR). For small values of SNR, the parameter estimation suffers from increased noise and impacts the communication performance. To improve the synchronization quality and thus decoder performance, the synchronizers are integrated into the iterative decoding structure. Intermediate results of the channel decoder after each iteration are used to improve the synchronization. This approach is referred to as code-aided (CA) synchronization or turbo synchronization. A number of CA synchronization algorithms have already been published but there is no publication so far on a generic hardware implementation of the CA synchronization. Therefore we present an algorithm which can be implemented efficiently in hardware and demonstrate its communication performance. Furthermore we present a high throughput, flexible, area and power efficient code-aided synchronization IP core for various satellite communication standards. The core is synthesized for 65 nm low power CMOS technology. After placement and routing the core has an area of 0.194 mm2, throughput of 207 Msymbols/s and consumes 41.4 mW at 300 MHz clock frequency. The architecture is designed in such a way that it does not affect throughput of the system.

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48

Grünewald, Jonas, Patricia Parlevliet, and Volker Altstädt. "Definition of process parameters for manufacturing of thermoplastic composite sandwiches – Part A." Journal of Thermoplastic Composite Materials 31, no. 6 (September 25, 2017): 745–66. http://dx.doi.org/10.1177/0892705717729013.

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Thermoplastic composite sandwich structures offer great potential to meet the demands of lightweight structures for aeronautical applications. In this study, compression moulding of sandwich components, consisting of carbon fibre reinforced polyether ether ketone (CF/PEEK) skins and polyetherimide (PEI) core structures, is studied by modelling the effect of processing conditions on the properties of the sandwich structure, particularly the skin to core bond. In order to predict the skin-to-core tensile bond strength, a theoretical model is deduced, which is based on intimate contact and autohesion, the two mechanisms governing the fusion bonding process. The bond model allows the prediction of the tensile bond strength depending on the skin and core pre-heat temperatures and allows a prognostication about the expected failure mechanisms. According to the model, sandwiches manufactured with skin pre-heat temperatures above 290°C and a core kept at room temperature will feature a sufficient bond strength to fail cohesively within the core. In addition, the model predicts that pre-heating the core improves the bond strength. A verification of the model will be published in a follow-up paper.

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49

Fajri, Dhirar Faisal, Alexander Agung, and Andang Widi Harto. "The Study of Floating Nuclear Power Plant Reactor Core Neutronic Parameters Using Scale 6.1 Code." International Journal on Advanced Science, Engineering and Information Technology 10, no. 5 (October 11, 2020): 1774. http://dx.doi.org/10.18517/ijaseit.10.5.6609.

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50

Dawahra, S., K. Khattab, and G. Saba. "Determination of the LEU core safety parameters of the MNSR reactor using the MCNP4C code." Annals of Nuclear Energy 63 (January 2014): 594–97. http://dx.doi.org/10.1016/j.anucene.2013.08.033.

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