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Achievable Rate Analysis and Optimization of Double-RIS Assisted Spatially Correlated MIMO with Statistical CSI

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China Communications 2025年第1期22卷 139-157页

作者： Xu Kaizhe Guo Jiajia Zhang Jun jin Shi Ma Shaodan Department of Communications and Networking Xi’an Jiaotong-Liverpool UniversitySuzhou 215123China State Key Laboratory of Internet of Things for Smart City University of MacaoMacao SARChina Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and TelecommunicationsNanjing 210003China National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China State Key Laboratory of Internet of Things for Smart City and the Department of Electrical and Computer Engineering University of MacaoMacao SARChina

Reconfigurable intelligent surface(RIS)is a novel meta-material which can form a smart radio environment by dynamically altering reflection directions of the impinging electromagnetic *** the prior literature,the inter-RIS links which also contribute to the performance of the whole system are usually neglected when multiple RISs are *** this paper we investigate a general double-RIS assisted multiple-input multiple-output(MIMO)wireless communication system under spatially correlated non line-of-sight propagation channels,where the cooperation of the double RISs is also *** design objective is to maximize the achievable ergodic rate based on full statistical channel state information(CSI).Specifically,we firstly present a closedform asymptotic expression for the achievable ergodic rate by utilizing replica method from statistical *** a full statistical CSI-enabled optimal design is proposed which avoids high pilot training overhead compared to instantaneous CSI-enabled *** further reduce the signal processing overhead and lower the complexity for practical realization,a common-phase scheme is proposed to design the double *** results show that the derived asymptotic ergodic rate is quite accurate even for small-sized antenna *** the proposed optimization algorithm can achieve substantial gain at the expense of a low overhead and ***,the cooperative double-RIS assisted MIMO framework is proven to achieve superior ergodic rate performance and high communication reliability under harsh propagation environment.

关键词： common reflection pattern double RISs large system analysis MIMO replica method

Variational Bayesian Tensor Quantile Regression

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Acta Mathematica Sinica,English Series 2025年第2期41卷 733-756页

作者： Yunzhi jin Yanqing Zhang Yunnan Key Laboratory of Statistical Modeling and Data Analysis Yunnan University Yunnan Key Laboratory of Statistical Modeling and Data Analysis Southwest United Graduate School Yunnan University

Quantile regression is widely used in variable relationship research for statistical *** quantile regression model is based on vector-valued covariates and can be efficiently estimated via traditional estimation methods. However, many modern applications involve tensor data with the intrinsic tensor structure. Traditional quantile regression can not deal with tensor regression issues well. To this end, we consider a tensor quantile regression with tensor-valued covariates and develop a novel variational Bayesian estimation approach to make estimation and prediction based on the asymmetric Laplace model and the CANDECOMP/PARAFAC decomposition of tensor coefficients. To incorporate the sparsity of tensor coefficients, we consider the multiway shrinkage priors for marginal factor vectors of tensor coefficients. The key idea of the proposed method is to efficiently combine the prior structural information of tensor and utilize the matricization of tensor decomposition to simplify the complexity of tensor coefficient estimation. The coordinate ascent algorithm is employed to optimize variational lower bound. Simulation studies and a real example show the numerical performances of the proposed method.

关键词： Asymmetric Laplace model CANDECOMP PARAFAC decomposition matricization tensor quantile regression variational Bayesian

Twist monomials of binary delta-matroids

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Acta Mathematica Sinica,English Series 2025年

作者： Qi YAN Xian'an jin School of Mathematics and Statistics Lanzhou University School of Mathematical Sciences Xiamen University

Recently, we introduced the twist polynomials of delta-matroids and gave a characterization of even normal binary delta-matroids whose twist polynomials have only one term and posed a problem:what would happen for odd binary delta-matroids? In this paper, we show that a normal binary deltamatroid whose twist polynomials have only one term if and only if each connected component of the intersection graph of the delta-matroid is either a complete graph of odd order or a single vertex with a loop.

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Analysis of Compressor Cascade Deviation and Surrogate Model Construction Based on Retained Lift

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Journal of Thermal Science 2025年第02期 567-578页

作者： HU Haojie jin Donghai Aeroengine Simulation Research Center School of Energy and Power EngineeringBeihang University

The through-flow method still plays an important role in the design of modern aero-engine,and its accuracy depends on the loss and deviation *** presence of tip clearance will impact the deviation distribution,while the retained lift is somewhat related to this *** achieve a more precise deviation model,this paper utilises the machine learning *** database comprises cascades with tip clearances in training,from which obtains a span-wise deviation model and executes its validation by comparing with experiment *** database is obtained by calculating 16 different geometries of the cascades with tip clearance in different working conditions,introducing the geometrical parameters of the cascades and retained lift as feature *** deviation and the retained lift follow the same trend with tip clearance size and operating conditions *** predict the span-wise distribution of the retained lift using the k-nearest neighbour regression,and then combine with the traditional model to get the distribution of the *** results show that the coefficient of determination of the retained lift coefficient prediction in the test set reaches 81.02%,and the mean absolute error is around 1.32%.Moreover,the trend predictions of cascade deviation distribution for different tip clearance size are all in good agreement with the experimental *** coefficient of determination of the prediction with the simulation is 75.23%,and the mean absolute error is 1.74%.

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Effects of acupuncture combined with bone-setting therapy to treat tourette syndrome:a three-arm randomized controlled trial

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Journal of Traditional Chinese Medicine 2025年第1期45卷 176-183页

作者： LANG Jiawang jin Lingqing LUO Jianchang LANG Boxu Department of Acupuncture and Massage Municipal Hospital Affiliated to Medical School of Taizhou University

OBJECTIVE: To explore the efficacy and safety of acupuncture combined with atlantoaxial joint bone-setting therapy for the treatment of Tourette syndrome. METHODS: We randomly divided 600 patients at a ratio of 1∶1∶1 into three groups: group A(acupuncture combined with atlantoaxial joint bone setting therapy group), group B(acupuncture group), and group C(tiapride group). After two months of treatment, the Yale global tic severity scale(YGTSS) score reduction, improvement in social function impairment, clinical efficacy, and long-term efficacy in the three groups were compared. RESULTS: After treatment, in the analysis of YGTSS score reduction, social function impairment improvement, the clinical control rate, and long-term efficacy, the results were all Group A > Group B > Group C, with a statistically significant difference(P < 0.05). However, the total clinical efficacy of treatment in group A(94.9%) was not significantly different from that in group B(91.8%). Adverse reactions did not occur in groups A and B, and several adverse reactions occurred in 29%(n = 58) of the group C patients. CONCLUSION: Compared with traditional drug therapy, acupuncture combined with atlantoaxial joint bone setting therapy has better clinical and long-term efficacy. This treatment strategy can improve the social function of children and prevent adverse reactions to drugs.

关键词： Tourette syndrome acupuncture atlanto-axial joint bone setting randomized controlled trial tiapride hydrochloride

Insight into catalytic performance and reaction mechanism for toluene total oxidation over Cu-Ce supported catalyst

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Journal of Environmental Sciences 2025年第3期149卷 476-487页

作者： Xuan Liang jin Zhang Juntai Tian Zenghua Xie Yue Liu Peng Liu Daiqi Ye School of Environment and Energy South China University of TechnologyGuangzhou 510006China National Engineering Laboratory for VOCs Pollution Control Technology and Equipment Guangzhou 510006China Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control South China University of TechnologyGuangzhou 510006China Guangdong Provincial Engineering and Technology Research Centre for Environmental Risk Prevention and Emergency Disposal South China University of TechnologyGuangzhou 510006China

Herein,three supported catalysts,CuO/Al_(2)O_(3),CeO_(2)/Al_(2)O_(3),and CuO-CeO_(2)/Al_(2)O_(3),were synthesized by the convenient impregnation method to reveal the effect of CeO_(2)addition on catalytic performance and reaction mechanism for toluene *** with CuO/Al_(2)O_(3),the T_(50)and T_(90)(the temperatures at 50%and 90%toluene conversion,respectively)of CuO-CeO_(2)/Al_(2)O_(3)were reduced by 33 and 39°C,respectively.N_(2)adsorptiondesorption experiment,XRD,SEM,EDS mapping,Raman,EPR,H_(2)-TPR,O_(2)-TPD,XPS,NH_(3)-TPD,Toluene-TPD,and in-situ DRIFTS were conducted to characterize these *** excellent catalytic performance of CuO-CeO_(2)/Al_(2)O_(3)could be attributed to its strong coppercerium interaction and high oxygen vacancies ***,in-situ DRIFTS proved that CuO-CeO_(2)/Al_(2)O_(3)promoted the conversion of toluene to benzoate and accelerated the deep degradation path of *** work provided valuable insights into the development of efficient and economical catalysts for volatile organic compounds.

关键词： Cu-Ce supported catalyst Copper-cerium interaction Oxygen vacancies Toluene oxidation Reaction mechanism

Vector meson’s spin alignments in high energy reactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 1-16页

作者： jin-Hui Chen Zuo-Tang Liang Yu-Gang Ma Xin-Li Sheng Qun Wang Key Laboratory of Nuclear Physics and Ion-beam Application(MoE) Institute of Modern PhysicsFudan UniversityShanghai 200433China Institute of Frontier and Interdisciplinary Science Key Laboratory of Particle Physics and Particle Irradiation(MOE)Shandong UniversityQingdao 266237China INFN-Firenze Sesto Fiorentino FI 50019Italy Department of Modern Physics University of Science and Technology of ChinaHefei 230026China School of Mechanics and Physics Anhui University of Science and TechnologyHuainan 232001China

The global spin alignment of vector mesons has been observed by the STAR collaboration at the Relativistic Heavy Ion Collider(RHIC)at Brookhaven National Laboratory(BNL).It provides a unique opportunity to probe the correlation between the po-larized quark and antiquark in the strongly coupled quark-gluon plasma(sQGP)produced in relativistic heavy ion collisions,opening a new window to explore the properties of *** addition,spin alignments of vector mesons have also been observed in other high-energy particle collisions such as e^(+)e^(−)annihilations at high energies where hadron production is dominated by quark fragmentation *** results obtained are quite different from those obtained in heavy ion collisions where quark coalescence/combination mechanism dominates suggesting strong dependence on hadronization *** comprehensive studies in different hadronization processes are *** this article,we present a brief review of theoretical and experimen-tal advances in the study of vector meson’s spin alignments in a variety of high-energy particle collisions,with emphasis on hadronization mechanisms.

关键词： vector meson spin alignment global polarization relativistic heavy ion collisions fragmentation

A regularization method for delivering the fourth-order derivative of experimental data and its applications in fluid-structure interactions

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Science China Technological Sciences 2025年第3期68卷 363-380页

作者： Fan DUAN jin-Jun WANG Fluid Mechanics Key Laboratory of Education Ministry Beijing University of Aeronautics and Astronautics

In the experimental investigation of fluid-structure interactions regarding the undulatory motion like flag flapping or fish swimming, solving the force distribution on the flexible body stands as an indispensable endeavor to gain insights into the underlying dynamic mechanisms. However, the solving process entails high-order numerical derivatives of experimental data, which poses a formidable challenge for experimental studies on fluid-structure interactions, given that the measurement noise inherent in experimental data renders the problem ill-posed. The commonly practiced regularization methods for numerical derivatives are feeble to tackle the fourth-order derivative associated with the bending force; those methods, in particular, require predetermined parameters about the unknown noise. We introduce here an empirical regularization method founded upon the kernel-term modification in the frequency domain, notably capable of determining the fourth derivative of experimental *** leveraging the potentials of the iterative operations, our method enables the reliable estimation of an approximately optimal regularization parameter, all without reliance on any a priori knowledge about the noise characteristics. To demonstrate the reliability, robustness, and accuracy of the method, we perform rigorous numerical assessments using different data models that are infused with noise varying several orders of magnitude. Additionally, practical application of this method is achieved in the experiment on a flexible film flapping in the gusty flow, where the spatiotemporal distribution of the bending force density on the film is calculated by integrating this method with a linear reconstruction.

关键词： high-order numerical derivative regularization film fluid-structure interactions bending force

CaH2-promoted activity of Ni-carbonate interface for CO_(2) methanation

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Journal of Energy Chemistry 2025年第1期100卷 522-532页

作者： jin-Peng Wang Guo-Cui Mao Hui-Lin Jiang Bao-Xia Dong Yun-Lei Teng School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002JiangsuChina

Transition metal-carbonate interfaces often act as active sites in heterogeneous catalytic *** interface between transition metal and metal carbonate exhibits a dynamic equilibrium during the CO_(2)hydrogenation reaction,involving surface carbonate hydrogenation and CO_(2)***,there have been few reports on engineering the activity of the interface between transition metal and alkaline earth metal carbonate for catalytic CO_(2)*** work demonstrated that the incorporation of CaH_(2)in Ni/CaCO_(3)enhances the CO_(2)methanation activity of the *** CO_(2)conversion for Ni/CaH_(2)-CaCO_(3)reached 68.5%at 400°C,which was much higher than that of the Ni/CaCO_(3)(31.6%) and Ni/CaH_(2)-CaO (42.4%) ***,the Ni/CaH_(2)-CaCO_(3)catalysts remained stable during the stability test for 24 h at 400°C and 8 *** research revealed that CaH_(2)played a crucial role in promoting the activity of the Ni-carbonate interface for CO_(2)***_(2)could modify the electronic structure of Ni and tune the structural properties of CaCO_(3)to generate medium basic sites (OH groups),which are favorable for the activation of H2and CO_(2).In-situ Fourier transform infrared spectroscopy (FTIR) analysis combined with density functional theory calculations demonstrated that CO_(2)activation occurs at the hydroxyl group (OH) on the CaH_(2)-modified Ni-carbonate surface,leading to the formation of CO_(3)H****,our study has confirmed that CO_(2)methanation over the Ni/CaH_(2)-CaCO_(3)catalysts proceeds via the formate pathway.

关键词： CO_(2)methanation Metal hydride Ni catalysts Carbonate Metal-carbonate interface