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Journal of Communications and Information Networks 2024年第2期9卷 151-161页

作者： Hongyu Li Jun gong Wenchi Cheng The 54th Research Institute of China Electronics Technology Group Corporation Shijiazhuang 050080China State Key Laboratory of Integrated Services Networks Xidian UniversityXi’an 710071China

Millimeter-wave (mmWave) is capable of achieving gigabit/second communication capacity and centimeter-level sensing accuracy and has become one of the main frequency bands for integrated sensing and communications (ISAC) research. Hybrid beamforming techniques have attracted much attention for solving the high path loss of mmWave and further reducing the hardware cost of the system. However, the related studies based on multicarrier and fully-connected hybrid architectures are still limited. For this reason,this paper investigates the orthogonal frequency division multiplexing (OFDM) based mmWave fully-connected hybrid architecture ISAC system to form a stable communication beam and dynamically varying sensing beam. In order to realize the aforementioned multifunctional beams, the hybrid beamformer design problem based on weighted error minimization of multicarrier is proposed and solved efficiently using the penalty dual decomposition (PDD) algorithm. Meanwhile, based on the echo model, the multicarrier multiple signal classification (MUSIC) algorithm for target angle of arrival estimation and the two-dimensional discrete Fourier transform(2D-DFT)algorithm for distance and velocity estimation are proposed, respectively. Numerical simulation results show that by adjusting the weighting factor,a flexible trade-off can be formed between the communication spectrum efficiency and the sensing accuracy error.

关键词： integrated sensing and communications hybrid beamforming fully-connected architecture millimeter-wave

Rockburst proneness considering energy characteristics and sample shape effects

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2441-2465页

作者： Song Luo Fengqiang gong Kang Peng Zhixiang Liu School of Resources and Safety Engineering Central South UniversityChangsha410083China School of Civil Engineering Southeast UniversityNanjing211189China

Accurate prediction of rockburst proneness is one of challenges for assessing the rockburst risk and selecting effective control *** study aims to assess rockburst proneness by considering the energy characteristics and qualitative information during rock *** representative rock types in cylindrical and cuboidal sample shapes were tested under uniaxial compression conditions and the failure progress was detected by a high-speed *** far-field ejection mass ratio(FEMR)was determined considering the qualitative failure information of the rock *** peak-strength energy impact index and the residual elastic energy index were used to quantitatively evaluate the rockburst proneness of both cylindrical and cuboidal ***,the performance of these two indices was analyzed by comparing their estimates with the *** results show that the accuracy of the residual elastic energy index is significantly higher than that of the peak-strength energy impact *** residual elastic energy index and the FEMR are in good agreement for both cylindrical and cuboidal rock *** is because these two indices can essentially reflect the common energy release mechanism characterized by the mass,ejection velocity,and ejection distance of rock *** suggests that both the FEMR and the residual elastic energy index can be used to accurately measure the rockburst proneness of cylindrical and cuboidal samples based on uniaxial compression test.

关键词： Rockburst proneness Sample shape Strain energy Energy release Far-field ejection mass ratio(FEMR)

Research,application and development of inorganic binder for casting process

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China Foundry 2024年第5期21卷 461-475页

作者： Xiao-long gong Sheng-li Hu Zi-tian Fan State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

Inorganic binder used in casting process has the advantages of low odor,labor-friendly conditions,and relatively low cost,which is one of the main development directions for casting molding materials in the ***,compared to organic binders(such as resin binders),inorganic binders exhibit lower bonding strength and are more sensitive to environmental *** sensitivity poses challenges,particularly in the reclamation of used sand,thus limiting their broader *** this paper,the research and application status of inorganic binders(mainly silicate inorganic binders)and their curing methods are *** addition,the research and application of phosphate inorganic binders and 3D printing inorganic binders that are being developed are ***,a detailed comparative analysis is conducted on the challenging issue of“reclamation for used sand”in the application of inorganic ***,the development direction of inorganic binders is clarified.

关键词： inorganic binder silicate system phosphate system 3D printing used sand reclamation development trend

Optical coherence tomography angiography metrics in different stages of diabetic macular edema

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Eye and Vision 2024年第3期10卷 13-20页

作者： Ruyi Han Ruowen gong Wei Liu Gezhi Xu Eye Institute and Department of Ophthalmology Eye and ENT Hospital of Fudan University83 Fenyang RoadShanghai200031People’s Republic of China Key Laboratory of Visual Impairment and Restoration Fudan UniversityShanghaiPeople’s Republic of China Key Laboratory of Myopia(Fudan University) Chinese Academy of Medical SciencesNational Health CommissionShanghaiPeople’s Republic of China

Background To investigate the optical coherence tomography angiography(OCTA)characteristics of diabetic macular edema(DME)at different *** This study was a cross-sectional *** diagnosed with DME were *** was classified into early,advanced,and severe *** vessel density(VD)in the superficial vascular plexus(SVP),deep vascular plexus(DVP)and foveal avascular zone(FAZ)parameters,including FAZ area,FAZ perimeter,acircularity index and foveal VD in a 300-μm-wide region around the FAZ(FD-300),were calculated by the AngioVue software.A multivariate generalized estimating equation was used to evaluate the associations between visual acuity and OCTA *** Ninety-two eyes from 74 patients with DME were included in this *** to early(P=0.006)and advanced DME(P=0.003),the acircularity index was higher in severe *** whole and parafoveal VD in the DVP decreased in eyes with severe DME compared to early DME(P=0.018,P=0.005,respectively)and advanced DME(P=0.035,P=0.012,respectively).In the multivariate generalized estimating equation,DME severity,FAZ area and foveal thickness were positively associated with worse visual acuity(P=0.001,P=0.007 and P=0.001,respectively).Conclusion Compared to early and advanced DME,severe DME showed increased irregularity in the FAZ and more extensive vessel damage in the *** severity level of DME,larger FAZ area,and increased foveal thickness could be risk factors for poor visual *** registration The protocol was published in the Chinese Clinical Trial Registry(ChiCTR2000033082).

关键词： Optical coherence tomography angiography Diabetic macular edema Vessel density Acircularity index

Room-temperature ferroelectricity in van der Waals SnP_(2)S_(6)

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Frontiers of physics 2024年第4期19卷 113-123页

作者： Chaowei He Jiantian Zhang Li gong Peng Yu State Key Laboratory of Optoelectronic Materials and Technologies Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable Devices Nanotechnology Research Center School of Materials Science and EngineeringSun Yat-sen UniversityGuangzhou 510275China Instrumental Analysis and Research Center Sun Yat-sen UniversityGuangzhou 510275China

Two-dimensional(2D)ferroelectric materials,which possess electrically switchable spontaneous polarization and can be easily integrated with semiconductor technologies,is of utmost importance in the advancement of high-integration low-power *** the experimental discovery of certain 2D ferroelectric materials such as CuInP2S6 and In2Se3,achieving stable ferroelectricity at room temperature in these materials continues to present a significant ***,stable ferroelectric order at room temperature in the 2D limit is demonstrated in van der Waals SnP_(2)S_(6) atom layers,which can be fabricated via mechanical exfoliation of bulk SnP_(2)S_(6) *** polarization is observed in thin SnP_(2)S_(6) of~7 ***,a van der Waals ferroelectric field-effect transistor(Fe-FET)with ferroelectric SnP_(2)S_(6) as top-gate insulator and ptype WTe0.6Se1.4 as the channel was designed and fabricated successfully,which exhibits a clear clockwise hysteresis loop in transfer characteristics,demonstrating ferroelectric properties of SnP_(2)S_(6) atomic *** addition,a multilayer graphene/SnP_(2)S_(6)/multilayer graphene van der Waals vertical heterostructure phototransistor was also fabricated successfully,exhibiting improved optoelectronic performances with a responsivity(R)of 2.9 A/W and a detectivity(D)of 1.4×10^(12) *** results show that SnP_(2)S_(6) is a promising 2D ferroelectric material for ferroelectric-integrated low-power 2D devices.

关键词： two-dimensional ferroelectric materials ferroelectric fieldeffect transistors photodetectors

Fast fixed-time three-dimensional terminal guidance with non-concave trajectory constraint

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Chinese Journal of Aeronautics 2024年第3期37卷 208-218页

作者： Youmin gong Yanning GUO Yueyong LYU Dongyu LI Guangfu MA Department of Control Science and Engineering Harbin Institute of TechnologyHarbin 150001China School of Cyber Science and Technology Beihang UniversityBeijing 100191China

Focusing on the non-concave trajectory constraint,a sliding-mode-based nonsingular feedback fast fixed-time three-dimensional terminal guidance of rotor unmanned aerial vehicle landing,planetary landing and spacecraft rendezvous and docking terminal phase with external disturbance is investigated in this ***,a fixed-time observer based on real-time differentiator is developed to compensate for the external disturbance,whose estimation error can converge to zero after a time independent of the initial ***,a sliding surface ensuring fixed-time convergence is *** sliding surface can guarantee that the vehicle achieves a non-concave trajectory,which is better for avoiding collision and maintaining the visibility of the landing site or docking ***,the nonsingular guidance ensuring the fixed-time convergence of the sliding surface is proposed,which is continuous and chatter *** last,three numerical simulations of Mars landing are performed to validate the effectiveness and correctness of the designed scheme.

关键词： Three-dimensional Terminal guidance Non-concave trajectory constraint Fast fixed-time control Sliding mode control

Freeze-induced acceleration of iodide oxidation and consequent iodination of dissolved organic matter to form organoiodine compounds

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Journal of Environmental Sciences 2024年第10期144卷 67-75页

作者： Xuexin gong Mei He Zhineng Hao Rusong Zhao Jingfu Liu School of Resources and Environment Yangtze UniversityWuhan 430100China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Qilu University of Technology(Shandong Academy of Sciences) Shandong Analysis and Test CenterKey Laboratory for Applied Technology of Sophisticated Analytical Instruments of Shandong ProvinceJinan 250014China Institute of Environment and Health Jianghan UniversityWuhan 430056China

Freeze-induced acceleration of I–oxidation and the consequent iodination of dissolved organic matter(DOM)contribute to the formation of organoiodine compounds(OICs)in cold *** formed OICs may be a potentially important source of risk and are very closely with the environment and human ***,we investigated the acceleration effects of the freeze process on I–oxidation and the formation of *** comparison to reactive iodine species(RIS)formed in aqueous solutions,I–oxidation and RIS formation were greatly enhanced in frozen solution and were affected by pH,and the content of I–and ***-thaw process further promoted I–oxidation and the concentration of RIS reached 45.7μmol/L after 6 freeze-thaw *** consequent products of DOM iodination were greatly promoted in terms of both concentration and *** total content of OICs ranged from 0.02 to 2.83μmol/L under various *** 183–1197 OICs were detected by Fourier transform ion cyclotron resonance mass spectrometry,and more than 96.2%contained one or two iodine *** OICs had aromatic structures and were formed via substitution and addition *** findings reveal an important formation pathway for OICs and shed light on the biogeochemical cycling of iodine in the natural aquatic environment.

关键词： Freeze process Dissolved organic matter(DOM) Iodination Organoiodine compounds(OICs) Ultrahigh resolution mass spectrometry

From tunnel boring machine to tunnel boring robot: perspectives on intelligent shield machine and its smart operation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第5期25卷 357-381页

作者： Yakun ZHANG Guofang gong Huayong YANG Jianbin LI Liujie JING State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310058China China Railway Engineering Equipment Group Co. Lid.Zhengzhou 450016China Maha Fluid Power Research Center Purdue UniversityWest LafayetteIN 47905USA

Advances in intelligent shield machines reflect an evolving trend from traditional tunnel boring machines(TBMs)to tunnel boring robots(TBRs).This shift aims to address the challenges encountered by the conventional shield machine industry arising from construction environment and manual *** study presents a systematic review of intelligent shield machine technology,with a particular emphasis on its smart ***,the definition,meaning,contents,and development modes of intelligent shield machines are *** development status of the intelligent shield machine and its smart operation are then *** analyzing the operation process of the shield machine,an autonomous operation framework considering both stand-alone and fleet levels is *** and recommendations are given for achieving autonomous *** study offers insights into the essence and developmental framework of intelligent shield machines to propel the advancement of this technology.

关键词： Intelligent shield machine Tunnel boring machine(TBM) Tunnel boring robot(TBR) Self-driving Autonomous control Shield machine

Therapeutic advances in atrial fibrillation based on animal models

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第2期25卷 135-152页

作者： Qian gong Xuan LE Pengcheng YU Lenan ZHUANG Institute of Genetics and Reproduction College of Animal SciencesZhejiang UniversityHangzhou310058China Key Laboratory of Cardiovascular Intervention and Regenerative Medicine of Zhejiang Province Department of CardiologySir Run Run Shaw HospitalSchool of MedicineZhejiang UniversityHangzhou310016China

Atrial fibrillation(AF)is the most prevalent sustained cardiac arrhythmia among humans,with its incidence increasing significantly with *** the high frequency of AF in clinical practice,its etiology and management remain *** develop effective treatment strategies,it is imperative to comprehend the underlying mechanisms of AF;therefore,the establishment of animal models of AF is vital to explore its *** spontaneous AF is rare in most animal species,several large animal models,particularly those of pigs,dogs,and horses,have proven as invaluable in recent years in advancing our knowledge of AF pathogenesis and developing novel therapeutic *** review aims to provide a comprehensive discussion of various animal models of AF,with an emphasis on the unique features of each model and its utility in AF research and *** data summarized in this review provide valuable insights into the mechanisms of AF and can be used to evaluate the efficacy and safety of novel therapeutic interventions.

关键词： Atrial fibrillation Animal model Therapeutic

Implications of the Stellar Mass Density of High-z Massive Galaxies from JWST on Warm Dark Matter

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Research in Astronomy and Astrophysics 2024年第1期24卷 128-134页

作者： Hengjie Lin Yan gong Bin Yue Xuelei Chen National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Science Center for China Space Station Telescope National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Department of Physics College of SciencesNortheastern UniversityShenyang 110819China Center for High Energy Physics Peking UniversityBeijing 100871China

A significant excess of the stellar mass density at high redshift has been discovered from the early data release of James Webb Space Telescope(JWST),and it may require a high star formation ***,this will lead to large number density of ionizing photons in the epoch of reionization(EoR),so that the reionization history will be changed,which can arise tension with the current EoR *** dark matter(WDM),via the free streaming effect,can suppress the formation of small-scale structure as well as low-mass *** provides an effective way to decrease the ionizing photons when considering a large star formation efficiency in high-z massive galaxies without altering the cosmic reionization *** the other hand,the constraints on the properties of WDM can be derived from the JWST *** this work,we study WDM as a possible solution to reconcile the JWST stellar mass density of high-z massive galaxies and reionization *** find that,the JWST high-z comoving cumulative stellar mass density alone has no significant preference for either CDM or WDM *** using the observational data of other stellar mass density measurements and reionization history,we obtain that the WDM particle mass with mw=0.51_(-0.12)^(+0.22) keV and star formation efficiency parameter f_(*)^(0)> 0.39 in 2σ confidence level can match both the JWST high-z comoving cumulative stellar mass density and the reionization history.

关键词： Cosmology (cosmology:)dark matter (cosmology:)large-scale structure of universe