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Improvement of the Bayesian neural network to study the photoneutron yield cross sections

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Nuclear Science and Techniques 2022年第11期33卷 1-9页

作者： yong-Yi Li Fan Zhang Jun su Department of Computing Changzhi UniversityChangzhi 046011China Department of Physics Changzhi UniversityChangzhi 046011China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China

This work is an attempt to improve the Bayesian neural network (BNN) for studying photoneutron yield cross sections as a function of the charge number Z, mass number A, and incident energy ε. The BNN was improved in terms of three aspects:numerical parameters, input layer, and network structure. First, by minimizing the deviations between the predictions and data, the numerical parameters, including the hidden layer number, hidden node number, and activation function, were selected. It was found that the BNN with three hidden layers, 10 hidden nodes, and sigmoid activation function provided the smallest deviations. Second, based on known knowledge,such as the isospin dependence and shape effect, the optimal ground-state properties were selected as input neurons. Third, the Lorentzian function was applied to map the hidden nodes to the output cross sections, and the empirical formula of the Lorentzian parameters was applied to link some of the input nodes to the output cross sections. It was found that the last two aspects improved the predictions and avoided overfitting, especially for the axially deformed nucleus.

关键词： Bayesian neural network Photoneutron cross sections Giant dipole resonance

MORPHOLOGICAL CHARACTERIZATION OF POLY (N-VINYLCARBAZOLE) OBTAINED WITH ASYMMETRICALLY STEREOSELECTIVE POLYMERIZATION

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Chinese Journal of Polymer Science 1999年第2期17卷 159-163页

作者： Quan su Chuan-fu Chen yong-ming Chen fu Xi PCLCC, Institute of Chemistry, Chinese Academy of Sciences. Beijing 100080, China 中科院化学所高分子化学联合开放实验室北京 100080 中科院化学所高分子化学联合开放实验室北京

The morphological characterizations of poly(N-vinylcarbazole)(PVCZ) obtained by asymmetrically stereoselective polymerization were studied using x-ray diffraction pattern, DSC and GPC. The results show that the PVCZs have lower crystallinities (11.0 similar to 18.6%) and lower melting heats (2.2 similar to 7.5 J/g), but the degree of crystallinities of the PVCZ samples obtained using the organic salts (acid) with chiral or stereodifferentiating ligands are higher than that using radical and general protonic initiator. It has shown that the crystallization is directly related to the packing density of the hexagonal array of the rodlike molecules formed from the helical chain.

关键词： crystal optically active poly(N-vinylcarbazole)

The Minimal Free Resolution of a Fat Star-Configuration in Pn

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Algebra Colloquium 2014年第1期21卷 157-166页

作者： Jeaman Ahn yong su Shin Department of Mathematics Education Kongju National University 182 Shinkwan-dong Kongju Chungnam 314-701 Korea Department of Mathematics Sungshin Women's University Seoul 136-742 Korea

Abstract. We find the minimal free resolution of a fat star-configuration X in Pn of type （r, s,t） defined by general forms of degrees d1,...,dr, and show that a fat linear star- configuration X in P2 never has generic Hilbert function if （s,t） ≠ （1, 1） or （2, 2）. These two results generalize the interesting results of [2].

关键词： Hilbert functions minimal free resolutions weak Lefschetz property fat star-configurations

Insight into the particle shape on the impact of dry granular flow against a rigid barrier: A DEM study

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Journal of Earth Science 2025年

作者： Rui-Xiao Zhan Dong su Xiang-Sheng Chen Yuan-Jun Jiang Guo-Ping Lei Jing-Jing Yu Key Laboratory for Resilient Infrastructures of Coastal Cities (MOE)， Shenzhen University College of Civil and Transportation Engineering， Shenzhen University School of Architecture and Urban Planning， Shenzhen University Shenzhen Key Laboratory of Green， Efficient and Intelligent Construction of Underground Metro Station， Shenzhen University Institute of Mountain Hazards and Environment， Chinese Academy of Sciences School of Transportation， Civil Engineering & Architecture， Foshan University

The effect of particle shape on the impact of dry granular flow remains an open area for further investigation. Five distinct particle shapes were examined in this study using discrete element simulations after calibrating the numerical model using a published work. The findings indicated that the particle shape had a significant influence on granular mobility. With negligible variations in normalized kinetic energy between particles of different shapes， the effect of particle shape on the increasing rate of kinetic energy became more obvious. All irregular particle scenarios had longer accumulated particle lengths down the channel than spherical particles. Variations in particle shape led to adjustments in the distribution of impact forces on the barrier. These findings substantially enhance our understanding of the distinctive effects of particle shapes on the impact mechanism of dry granular flow.

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Analysis on the influencing factors of radioactive tritium leakage and diffusion from an indoor high‑pressure storage vessel

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Nuclear Science and Techniques 2022年第12期33卷 1-11页

作者： Chang‑Jun Li Xing‑fu Cai Ming‑Qing Xiao yong‑Gang Huo Peng Xu su‑Fen Li Xiao‑Yan Cao Xi’an Research Institute of High-Tech Xi’an 710025China Air Force Engineering University Xi’an 710051China

Radioactive tritium leakage from high-pressure storage vessels is a common nuclear leakage *** leakage conditions have different effects on tritium diffusion,resulting in different degrees of radioactive *** study focuses on tritium leakage from high-pressure storage vessels and analyzes the influence of different leakage orifice shapes,leakage positions,and the presence of obstacles in the scene space on tritium leakage *** results show that there is little difference in the radial diffusion velocity of tritium gas along the jet axis between circular and square leakage *** radial diffusion velocity of tritium gas in the long-axis direction of the rectangular leakage orifice is larger than that in the short-axis direction,and the larger the aspect ratio of the rectangle is,the greater the difference is in the diffusion *** addition,leakage from the storage vessel below the air inlet is beneficial to the dilution of tritium,whereas leakage from the air vents leads to a slow decrease in the tritium *** obstacles present in the tritium scene space hinder the migration of tritium gas and prolong the time for the tritium concentration to reach *** study provides a theoretical basis for the disposal of tritium in tritium leakage accidents by analyzing the influence of different leakage conditions in storage vessels on tritium gas diffusion.

关键词： Tritium leakage Leakage orifice shape Leakage position Obstacles

Effect of pouring time on microstructure and mechanical properties of centrifugal cast Ti-46Al alloy tubes

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China Foundry 2025年

作者： Gang Huang Qian Dang Cong-cong su Jing Zhao Chi Zhang Guo-huai Liu Zhao-dong Wang The State Key Laboratory of Rolling and Automation Northeastern University School of Materials Science and Engineering Shenyang University of Technology

The grain size of TiAl alloy castings prepared by traditional casting process is coarse, thus showing poor mechanical properties. In this study, a new type of high performance Ti-46Al alloy tube prepared by vacuum centrifugal casting technology was introduced. This research comprehensively examined the influence of pouring time on the microstructure and mechanical performance of the castings, employing both experimental approaches and ProCast simulation methodologies. The findings indicate that prolonging the pouring time facilitates a microstructural evolution from coarse columnar grains to refined equiaxed grains. Under the condition of pouring temperature of 1,600 °C, rotation speed of 800 r·min-1and pouring time of 6 s, the tensile strength of Ti-46Al alloy at room temperature reaches 650 MPa, and the tensile strength at 800 °C reaches 705 MPa, which is significantly higher than that of traditional as-cast Ti-Al alloy.

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Microstructure and mechanical properties of Ti43Al6Nb alloys with different zirconium contents

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Rare Metals 2023年第6期42卷 2047-2056页

作者： Xiao-Ye Zhao Rui-Run Chen yong Yang Jing-Jie Guo Hong-Sheng Ding Yan-Qing su Heng-Zhi fu School of Materials Science and Engineering Harbin Institute of TechnologyHarbin150001China

Ti43Al6Nb-xZr alloys with different additions of zirconium were prepared by vacuum arc melting *** microstructure and compressive properties at room temperature(RT) were *** microstructure shows dendrites with addition of 0 at%-2.5at% Zr,and the dendrites are refined with the primary dendrite arms spacing decreasing from 222.64 μm(0 at%Zr) to 92.57 μm(2.0 at% Zr).With Zr addition more than2.5 at%,the microstructure shows equiaxed grains surrounded by y *** is a y stabilizer and promotes the β/y transition,resulting in the change of microstructure *** reaches the maximum solid solubility(about 6.5 at%) in y phase with addition of 2.5 at% Zr;moreover,γ phase increases in quantity,bringing about severe *** addition of Zr,the remained β phase turns into ω phase with B82 ***43Al6Nb-xZr alloys show brittle *** maximum compressive strength is 2161.69 MPa with addition of 2.5at% Zr and the maximum compressive strain is 30.62%with addition of 0.5 at% Zr,improving by 9.24% and7.33%,*** improvement of compressive strength results from fine-grain strengthening and solution *** micro-segregation is bad for compressive strength,and large solubility of Zr is detrimental to ductility.

关键词： TiAl alloys Zr Microstructure evolution Micro-segregation Mechanical properties

A Geometric Based Connection between Fractional Calculus and Fractal functions

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Acta Mathematica Sinica,English Series 2024年第2期40卷 537-567页

作者： yong Shun LIANG Wei Yi su School of Mathematics and Statistic Nanjing University of Science and TechnologyNanjing 210094P.R.China Department of Mathematics Nanjing UniversityNanjing 210023P.R.China

Establishing the accurate relationship between fractional calculus and fractals is an important research content of fractional calculus *** the present paper,we investigate the relationship between fractional calculus and fractal functions,based only on fractal dimension *** dimension of the Riemann-Liouville fractional integral of continuous functions seems no more than fractal dimension of functions *** fractal dimension of the Riemann-Liouville fractional differential of continuous functions seems no less than fractal dimension of functions themselves when they *** further discussion,fractal dimension of the Riemann-Liouville fractional integral is at least linearly decreasing and fractal dimension of the Riemann-Liouville fractional differential is at most linearly increasing for the Holder continuous *** about other fractional calculus,such as the Weyl-Marchaud fractional derivative and the Weyl fractional integral has also been given *** work is helpful to reveal the mechanism of fractional calculus on continuous *** the same time,it provides some theoretical basis for the rationality of the definition of fractional *** is also helpful to reveal and explain the internal relationship between fractional calculus and fractals from the perspective of geometry.

关键词： Fractional calculus fractal functions fractal dimension fractional calculus equation relationship

Effective interactions between two impurities in quasi-two-dimensional dipolar Bose–Einstein condensates

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Communications in Theoretical Physics 2020年第7期72卷 65-70页

作者： fu-Lin Deng Tao Shi su Yi CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100049China

We investigate the effective interaction between two heavy impurities immersed in a quasi-twodimensional dipolar Bose-Einstein condensate via a variation *** show that the mediated interaction is highly tunable via the contact and the dipole-dipole interactions between the background gas ***,the mediated interaction potential may become an oscillating function of inter-impurity distance when roton excitation emerges under sufficiently strong dipolar *** system therefore provides an efficient way for tuning the mediated interaction between impurities.

关键词： dipolar gas impurity effective interaction roton excitation