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China Communications 2024年第1期21卷 242-259页

作者： Hao jiang Hongming Zhang ting Liu College of Artificial Intelligence Nanjing University of Information Science and Technology210044China National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsChina

In this paper,a statistical cluster-based simulation channel model with a finite number of sinusoids is proposed for depicting the multiple-input multiple-output(MIMO)communications in vehicleto-everything(V2X)*** the proposed sum-of-sinusoids(SoS)channel model,the waves that emerge from the transmitter undergo line-of-sight(LoS)and non-line-of-sight(NLoS)propagation to the receiver,which makes the model suitable for describing numerous V2X wireless communication scenarios for sixth-generation(6G).We derive expressions for the real and imaginary parts of the complex channel impulse response(CIR),which characterize the physical propagation characteristics of V2X wireless *** statistical properties of the real and imaginary parts of the complex CIRs,i.e.,autocorrelation functions(ACFs),Doppler power spectral densities(PSDs),cross-correlation functions(CCFs),and variances of ACFs and CCFs,are derived and *** results are generated and match those predicted by the underlying theory,demonstrating the accuracy of our derivation and *** proposed framework and underlying theory arise as an efficient tool to investigate the statistical properties of 6G MIMO V2X communication systems.

关键词： complex CIRs LoS and NLoS propagation components MIMO V2X communication environments SoS simulation channel model statistical properties

An overview and perspective of identifying lunar craters

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Science China Earth Sciences 2024年第5期67卷 1395-1416页

作者： Yan jiang Changyi Xu ling CHEN State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100029China Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100049China

The spatiotemporal evolution of lunar impact craters is crucial for investigating lunar interior structure,internal and external dynamic processes,and interplanetary impact *** in lunar crater identification are reviewed based on topography and gravity data,and the features and mechanisms of topographic or buried craters are analyzed regarding morphology,gravity anomalies,gravity gradients,and the underlying crust-mantle interface *** on the compiled crater catalog,the early lunar impact flux and thermal evolution are further discussed according to the basin ages and their interior *** some ancient impact basins,the crater size-frequency distribution measurements revealed age discrepancies from previous studies,suggesting that the lunar late heavy bombardment event started at~3.95 *** degraded bulge structures of the crust-mantle interface beneath mare basins reveal that these basins formed on the lunar crust surface under high-temperature conditions and underwent prolonged relaxation compared to highland ***,we reveal that the up-to-date identification of lunar buried craters remains inaccurate and incomplete,preventing us from accurately reconstructing lunar and interplanetary impact ***,we propose that a gravity model constructed using localized orthogonal basis functions can be useful for identifying lunar craters.

关键词： Moon Gravity field Craters Impact flux Early evolution

Online Pareto optimal control of mean-field stochastic multi-player systems using policy iteration

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Science China(Information Sciences) 2024年第4期67卷 21-37页

作者： Xiushan jiang Yanshuang WANG Dongya ZHAO ling SHI College of New Energy China University of Petroleum(East China) Department of Electronic and Computer Engineering Hong Kong University of Science and Technology

In this study, the Pareto optimal strategy problem was investigated for multi-player mean-field stochastic systems governed by It? differential equations using the reinforcement learning(RL) method.A partially model-free solution for Pareto-optimal control was derived. First, by applying the convexity of cost functions, the Pareto optimal control problem was solved using a weighted-sum optimal control problem. Subsequently, using on-policy RL, we present a novel policy iteration(PI) algorithm based on the Hrepresentation technique. In particular, by alternating between the policy evaluation and policy update steps,the Pareto optimal control policy is obtained when no further improvement occurs in system performance,which eliminates directly solving complicated cross-coupled generalized algebraic Riccati equations(GAREs).Practical numerical examples are presented to demonstrate the effectiveness of the proposed algorithm.

关键词： mean-field stochastic systems Pareto optimal control policy iteration scheme $\mathcal{H}$-representation

New black-to-white hole solutions with improved geometry and energy conditions

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 30-43页

作者： Zhongwen Feng Yi ling Xiaoning Wu Qingquan jiang School of Physics and Astronomy China West Normal UniversityNanchong 637009China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China School of Physics University of Chinese Academy of SciencesBeijing 100049China Institute of Mathematics Academy of Mathematics and System Science and Hua Loo-Keng Key Laboratory of MathematicsChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100190China

We construct new black-to-white hole solutions which connect the geometry of spacetime at some gluing surface inside the *** continuity of the metric can be guaranteed up to the arbitrary order which is controlled by the power factor *** sort of black-to-white holes is characterized by the sub-Planckian scalar curvature,independent of the mass of black-to-white *** importantly,we show that the energy condition is only violated within a small region near the gluing *** geodesics of particles within the region from black hole to white hole is also *** turns out that the matter falling into the black hole may pass through the center without singularity and come out from the white *** scenario provides novel ideas for understanding the information loss paradox in traditional black hole physics.

关键词： regular black hole energy condition singularity quantum gravity

Joint Optimization of Resource Allocation and Trajectory Based on User Trajectory for UAV-Assisted Backscatter Communication System

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China Communications 2024年第2期21卷 197-209页

作者： Peizhong Xie Junjie jiang ting Li Yin Lu School of Communication and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China Key Lab of Broadband Wireless Communication and Sensor Network Technology(Nanjing University of Posts and Telecommunications) Ministry of EducationNanjing 210003China

The Backscatter communication has gained widespread attention from academia and industry in recent years. In this paper, A method of resource allocation and trajectory optimization is proposed for UAV-assisted backscatter communication based on user trajectory. This paper will establish an optimization problem of jointly optimizing the UAV trajectories, UAV transmission power and BD scheduling based on the large-scale channel state signals estimated in advance of the known user trajectories, taking into account the constraints of BD data and working energy consumption, to maximize the energy efficiency of the system. The problem is a non-convex optimization problem in fractional form, and there is nonlinear coupling between optimization *** iterative algorithm is proposed based on Dinkelbach algorithm, block coordinate descent method and continuous convex optimization technology. First, the objective function is converted into a non-fractional programming problem based on Dinkelbach method,and then the block coordinate descent method is used to decompose the original complex problem into three independent sub-problems. Finally, the successive convex approximation method is used to solve the trajectory optimization sub-problem. The simulation results show that the proposed scheme and algorithm have obvious energy efficiency gains compared with the comparison scheme.

关键词： energy efficiency joint optimization UAV-assisted backscatter communication user trajectory

Electronic modulation of sprout-shaped NiCoP nanoarrays by N and Ce doping for efficient overall water splitting

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Nano Research 2024年第1期17卷 282-289页

作者： ting Zhao Guancheng Xu Bingbing Gong Jiahui jiang Li Zhang State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources College of ChemistryXinjiang UniversityUrumqi 830017China College of Chemical Engineering Xinjiang UniversityUrumqi 830017China

Bifunctional catalysts for hydrogen/oxygen evolution reactions(HER/OER)are urgently needed given the bright future of water splitting hydrogen production ***,the self-supporting N and Ce dual-doped NiCoP nanoarrays(denoted N,Ce-NiCoP/NF)grown on Ni foam are successfully *** the N,Ce-NiCoP/NF simultaneously acts as the HER and OER electrodes,the voltages of 1.54 and 2.14 V are obtained for driving 10 and 500 mA·cm^(-2)with a robust durability,and demonstrate its significant potential for practical water *** to both experiments and calculations,the electronic structure of NiCoP may be significantly altered by strategically incorporating N and Ce into the lattice,which in turn optimizes the Gibbs free energy of HER/OER intermediates and speeds up the water splitting ***,the sprout-shaped morphology significantly increases the exposure of active sites and facilitates charge/mass transfer,thereby augmenting catalyst *** study offers a potentially effective approach involving the regulation of anion and cation double doping,as well as architectural engineering,for the purpose of designing and optimizing innovative electrocatalysts.

关键词： transition metal phosphides overall water splitting elements doping nanoarrays

Histological Features of Uterine Myometrial Dysfunction:Possible Involvement of Localized Inflammation

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Current Medical Science 2024年第3期44卷 633-641页

作者： Sheng-lan ZHU Hui-ting ZHANG Yuan-yuan DU Yi jiang Shao-shuai WANG Wen-cheng DING ling FENG National Clinical Research Center for Obstetrics and Gynecology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Department of Obstetrics and Gynecology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China

Objective The latest perspective suggests that elevated levels of inflammation and cytokines are implicated in atonic postpartum ***(LPS)has been widely used to induce inflammation in animal ***,this study aimed to induce uterine inflammation using LPS to investigate whether local inflammation triggers dysfunction and atrophy in the myometrium,as well as the potential underlying molecular mechanisms *** In vivo,an animal model was established by intraperitoneal injection of 300μg/kg LPS in rats on gestational day ***-eosin(H&E)staining and Masson staining were employed to determine morphological changes in the rat uterine smooth ***-linked immunosorbent assay(ELISA)was used to detect inflammatory ***,tissue fluorescence,and Western blotting were conducted to assess the expression levels of the uterine contraction-related proteins Toll-like receptor 4(TLR4)and the nuclear factor kappa-B(NF-κB)signaling *** vitro,human uterine smooth muscle cells(HUtSMCs)were exposed to 2μg/mL LPS to further elucidate the involvement of the TLR4/NF-κB signaling pathway in LPS-mediated *** In this study,LPS induced uterine myometrial dysfunction in rats,leading to a disorganized arrangement,a significant increase in collagen fiber deposition,and widespread infiltration of inflammatory *** both in vivo animal models and in vitro HUtSMCs,LPS elevated IL-6,IL-1β,and TNF-αlevels while concurrently suppressing the expression of connexin 43(Cx43)and oxytocin receptor(OXTR).Mechanistically,the LPS-treated group exhibited TLR4 activation,and the phosphorylation levels of p65 and IκBαwere notably *** LPS triggered the TLR4/NF-κB signaling pathway,inducing an inflammatory response in the myometrium and leading to uterine myometrial dysfunction and uterine atony.

关键词： lipopolysaccharide inflammatory response TLR4 NF-κB myometrium

Effects of asymmetric coupling and boundary on the dynamic behaviors of a random nearest neighbor coupled system

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Chinese Physics B 2024年第6期33卷 309-322页

作者：徐玲姜磊 School of Mathematical Sciences Sichuan Normal UniversityChengdu 610066China School of Mathematics and Statistics Linyi UniversityLinyi 276000China

This study investigates the dynamical behaviors of nearest neighbor asymmetric coupled systems in a confined ***, the study derivative analytical stability and synchronization conditions for the asymmetrically coupled system in an unconfined space, which are then validated through numerical simulations. Simulation results show that asymmetric coupling has a significant impact on synchronization conditions. Moreover, it is observed that irrespective of whether the system is confined, an increase in coupling asymmetry leads to a hastened synchronization pace. Additionally, the study examines the effects of boundaries on the system's collective behaviors via numerical experiments. The presence of boundaries ensures the system's stability and synchronization, and reducing these boundaries can expedite the synchronization process and amplify its effects. Finally, the study reveals that the system's output amplitude exhibits stochastic resonance as the confined boundary size increases.

关键词： asymmetric coupled confined space synchronization stochastic resonance stability

Mechanism study of Cu(Ⅱ) adsorption from acidic wastewater by ultrasonic-modified municipal solid waste incineration fly ash

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Chinese Journal of Chemical Engineering 2024年第3期67卷 157-165页

作者： Shunda lin Yang Lu Lin Zheng ling Long Xuguang jiang Jianhua Yan State Key Laboratory of Clean Energy Utilization Institute for Thermal Power EngineeringZhejiang UniversityHangzhou 310027China Zhejiang University Qingshanhu Energy Research Center Hangzhou 310027China Hangzhou Xiaoshan Jinjiang Green Energy Co. Ltd.XiaoshanHangzhou 310000China

High concentrations of copper ions(Cu(Ⅱ)) in water will pose health risks to humans and the ecological environment. Therefore, this study aims to utilize ultrasonic-cured modified municipal solid waste incineration(MSWI) fly ash for Cu(Ⅱ) adsorption to achieve the purpose of “treating waste by waste.” The effects of p H, adsorption time, initial concentration, and temperature on the modified MSWI fly ash’s adsorption efficiency were systematically studied in this article. The adsorption performance of the modified MSWI fly ash can be enhanced by the ultrasonic modification. At pH = 2, 3 and 4, the adsorption capacity of the modified MSWI fly ash for Cu(Ⅱ) increased by 2.7, 1.9 and 1.2 times, respectively. Furthermore, it was suggested that the adsorption process of the modified MSWI fly ash can be better simulated by the pseudo-second-order kinetic model, with a maximum adsorption capacity calculated by the Langmuir model of 24.196 mg.g-1. Additionally, the adsorption process is spontaneous,endothermic, and chemisorption-dominated from the thermodynamic studies(ΔH and ΔS > 0, ΔG < 0).Finally, the enhanced adsorption performance of the modified MSWI fly ash for Cu(Ⅱ) may be attributed to electrostatic interaction and chelation effects.

关键词： Ultrasound MSWI fly ash Cu(Ⅱ) Wastewater Adsorption

Strength and ductility optimization of HPDC AlSi8MgCuZn2 alloys by modifying pre-aging treatment

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China Foundry 2024年第4期21卷 343-351页

作者： Yuan-hang jiang Hui-ting Zheng Fei Liu Hai-dong Zhao National Engineering Research Center of Near-net Shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510641China

Considering the components produced by high pressure die casting(HPDC)process usually with ultra-large sizes and complex morphologies,high temperature solid solution treatment is not a suitable method to further improve their mechanical *** this study,two-stage aging treatment with different pre-aging times was designed and employed to further improve the mechanical properties of HPDC Al8SiMgCuZn *** characteristics of precipitates were evaluated by a transmission electron microscope(TEM),and the precipitation strengthening mechanism was *** results reveal that the strengthening is mainly contributed by the precipitation ofβ″phase after two-stage aging,and the number density and size of the precipitates are significantly depended on the pre-aging *** number density of precipitates is increased with the pre-aging time prolonged from 0 h to 4 h,and then decreases with the further increase of pre-aging time from 4 h to 6 *** precipitates with the highest density and smallest size are observed after pre-aging for 4 *** pre-aged at 100℃for 4 h and then artificial aged at 200℃for 30 min,the yield strength of 207 MPa,ultimate tensile strength of 325 MPa and elongation of 7.6%are achieved.

关键词： high pressure die cast aluminum alloy microstructural heterogeneity mechanical properties precipitation strengthening two-stage aging