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Coarse-fine joint target parameter estimation method based on AN-RSC in OFDM passive radar

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Journal of Systems Engineering and Electronics 2024年第2期35卷 339-349页

作者： wanG Chujun wan Xianrong yi Jianxin CHENG Feng School of Electronic Information Wuhan UniversityWuhan 430072China

In this paper,we study the accuracy of delay-Doppler parameter estimation of targets in a passive radar using orthogonal frequency division multiplexing(OFDM)signal.A coarse-fine joint estimation method is proposed to achieve better estimation accuracy of target parameters without excessive computational ***,the modulation symbol domain(MSD)method is used to roughly estimate the delay and Doppler of ***,to obtain high-precision Doppler estimation,the atomic norm(AN)based on the multiple measurement vectors(MMV)model(MMV-AN)is used to manifest the signal sparsity in the continuous Doppler *** the same time,a reference signal compensation(RSC)method is presented to obtain highprecision delay *** results based on the OFDM signal show that the coarse-fine joint estimation method based on AN-RSC can obtain a more accurate estimation of target parameters compared with other *** addition,the proposed method also possesses computational advantages compared with the joint parameter estimation.

关键词： passive radar orthogonal frequency division multiplexing(OFDM)signal atomic norm(AN) parameter estimation

Synthesis of Diverse Oxetane Amino Acids via Visible-Light-Induced Photocatalytic Decarboxylative Giese-Type Reaction

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Chinese Journal of Chemistry 2024年第12期42卷 1341-1346页

作者： Haoliang Shi yi wan Yongqiang Zhang Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism Shanghai Key Laboratory of New Drug Designand School of PharmacyEast China University of Science and TechnologyShanghai200237 China

The divergent synthesis of versatile 3,3′-disubstituted oxetane amino acids by utilizing visible-light-induced photocatalytic decarboxylative Giese-type reaction has been demonstrated.3-Methyleneoxetane-derived substrates are readily available in a single-step and highly reactive as radical acceptors,allowing the production of versatile oxetaneγ-andα-amino acids in high yields.A distinct ring strain release-driven radical addition mechanism was preliminarily *** preparative power was further highlighted by the application in the synthesis of oxetane-containing dipeptides and azetidine amino acids,as well as the transformation of the product into novel oxetane-containing spiro-heterocycle pharmacophore.

关键词： Photoredox catalysis Decarboxylative Giese-type reaction Oxetane amino acids Amino acids Synthesis Radical reactions

Metamaterial terahertz device with temperature regulation function that can achieve perfect absorption and complete reflection conversion of ultrawideband

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Communications in Theoretical Physics 2024年第7期76卷 123-133页

作者： Hao Sun zao yi Can Ma Shubo Cheng Bin Tang Qingdong Zeng Sohail Ahmad School of Mathematics and Science Joint Laboratory for Extreme Conditions Matter PropertiesState Key Laboratory of Environment-Friendly Energy MaterialsTianfu Institute of Research and InnovationSouthwest University of Science and TechnologyMianyang 621010China Department of Oncology Sichuan Science City HospitalMianyangSichuan Province621000China School of Chemistry and Chemical Engineering Jishou UniversityJishou 416000China School of Physics and Optoelectronic Engineering Yangtze UniversityJingzhouHubei 434023China School of Microelectronics and Control Engineering Changzhou UniversityChangzhou 213164China School of Physics and Electronic Information Engineering Hubei Engineering UniversityXiaogan 432000China Institute of Physics Bahauddin Zakariya UniversityMultan 66000Pakistan

The field of terahertz devices is important in terahertz ***,most of the current devices have limited functionality and poor *** improve device performance and achieve multifunctionality,we designed a terahertz device based on a combination of VO_(2)and *** device can be tuned using the phase-transition characteristics of VO_(2),which is included in the triple-layer structure of the device,along with SiO_(2)and *** terahertz device exhibits various advantageous features,including broadband coverage,high absorption capability,dynamic tunability,simple structural design,polarization insensitivity,and incidentangle *** simulation results showed that by controlling the temperature,the terahertz device achieved a thermal modulation range of spectral absorption from 0 to *** 313 K,the device exhibited complete reflection of terahertz *** the temperature increased,the absorption rate also *** the temperature reached 353 K,the device absorption rate exceeded 97.7%in the range of 5-8.55 *** study used the effective medium theory to elucidate the correlation between conductivity and temperature during the phase transition of VO_(2).Simultaneously,the variation in device performance was further elucidated by analyzing and depicting the intensity distribution of the electric field on the device surface at different ***,the impact of various structural parameters on device performance was examined,offering valuable insights and suggestions for selecting suitable parameter values in real-world *** characteristics render the device highly promising for applications in stealth technology,energy harvesting,modulation,and other related fields,thus showcasing its significant potential.

关键词： terahertz perfect absorption complete reflection temperature regulation ultrawideband smart device

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Acyclic Edge Coloring of 1-planar Graphs without 4-cycles

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 35-44页

作者： Wei-fan wang yi-qiao wang wan-shun Yang Department of Mathematics Zhejiang Normal UniversityJinhua321004China School of Management Beijing University of Chinese MedicineBeijing100029China School of Mathematics and Information Science Weifang UniversityWeifang261061China

An acyclic edge coloring of a graph G is a proper edge coloring such that there are no bichromatic cycles in *** acyclic chromatic index χ'α(G) of G is the smallest k such that G has an acyclic edge coloring using k *** was conjectured that every simple graph G with maximum degree Δ has χ'_α(G) ≤Δ+2.A1-planar graph is a graph that can be drawn in the plane so that each edge is crossed by at most one other *** this paper,we show that every 1-planar graph G without 4-cycles has χ'_α(G)≤Δ+22.

关键词： 1-planar graph acyclic edge coloring acyclic chromatic index

Multi-functional metasurface:ultra-wideband/multi-band absorption switching by adjusting guided-mode resonance and local surface plasmon resonance effects

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Communications in Theoretical Physics 2024年第6期76卷 174-184页

作者： Wenxin Li Shubo Cheng Huafeng Zhang zao yi Bin Tang Can Ma Pinghui Wu Qingdong Zeng Rizwan Raza School of Physics and Optoelectronic Engineering Yangtze UniversityJingzhouHubei 434023China Joint Laboratory for Extreme Conditions Matter Properties Southwest University of Science and TechnologyMianyang 621010China School of Chemistry and Chemical Engineering Jishou UniversityJishou 416000China School of Microelectronics and Control Engineering Changzhou UniversityChangzhou 213164China Department of Oncology Sichuan Science City HospitalMianyangSichuan Province 621000China Office of Science and Technology Quanzhou Normal UniversityQuanzhou 362000China School of Physics and Electronic-information Engineering Hubei Engineering UniversityXiaogan 432000China Department of Physics COMSATS Institute of Information Technology 54000 LahorePakistan

This study introduces an innovative dual-tunable absorption film with the capability to switch between ultra-wideband and narrowband *** manipulating the temperature,the film can achieve multi-band absorption within the 30-45 THz range or ultra-wideband absorption spanning 30-130 THz,with an absorption rate exceeding ***,the structural parameters of the absorption film are optimized using the particle swarm optimization(PSO)algorithm to ensure the optimal absorption *** absorption response of the film is primarily attributed to the coupling of guided-mode resonance and local surface plasmon resonance *** film's symmetric structure enables polarization incoherence and allows for tuning through various means such as doping/voltage,temperature and structural *** the case of a multi-band absorption response,the film exhibits good sensitivity to refractive index changes in multiple absorption ***,the absorption spectrum of the film remains effective even at large incidence angles,making it highly promising for applications in fields such as biosensing and infrared stealth.

关键词： PSO optimization ultra-wideband/narrowband absorption switching intelligent absorption film vanadium dioxide

RFFsNet-SEI:a multidimensional balanced-RFFs deep neural network framework for specific emitter identification

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Journal of Systems Engineering and Electronics 2024年第3期35卷 558-574,F0002页

作者： FAN Rong SI Chengke HAN yi wan Qun School of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Institute of Electronic and Electrical Engineering Civil Aviation Flight University of ChinaGuanghan 618307China

Existing specific emitter identification(SEI)methods based on hand-crafted features have drawbacks of losing feature information and involving multiple processing stages,which reduce the identification accuracy of emitters and complicate the procedures of *** this paper,we propose a deep SEI approach via multidimensional feature extraction for radio frequency fingerprints(RFFs),namely,***,we extract multidimensional physical RFFs from the received signal by virtue of variational mode decomposition(VMD)and Hilbert transform(HT).The physical RFFs and I-Q data are formed into the balanced-RFFs,which are then used to train *** introducing model-aided RFFs into neural network,the hybrid-driven scheme including physical features and I-Q data is *** improves physical interpretability of ***,since RFFsNet-SEI identifies individual of emitters from received raw data in end-to-end,it accelerates SEI implementation and simplifies procedures of ***,as the temporal features and spectral features of the received signal are both extracted by RFFsNet-SEI,identification accuracy is ***,we compare RFFsNet-SEI with the counterparts in terms of identification accuracy,computational complexity,and prediction *** results illustrate that the proposed method outperforms the counterparts on the basis of simulation dataset and real dataset collected in the anechoic chamber.

关键词： specific emitter identification(SEI) deep learning(DL) radio frequency fingerprint(RFF) multidimensional feature extraction(MFE) variational mode decomposition(VMD)

Numerical simulation of liquid sloshing in a spherical tank by MPS method

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Journal of Hydrodynamics 2024年第2期36卷 232-240页

作者： Cong-yi Huang Ji-fei wang Wei-wen Zhao De-cheng wan Computational Marine Hydrodynamic Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China Shanghai Aerospace System Engineering Institute Shanghai201109China

This paper investigates the sloshing phenomena in a spherical liquid tank using the moving particle semi-implicit(MPS)method,a crucial study in fluid *** from previous research focused on rectangular or LNG tanks,this work explores the unique motion patterns inherent to spherical *** accuracy of our in-house MPS solver MLParticle-SJTU is validated against experimental data and finite volume method(FVM).And the MPS method reveals a closer alignment with experimental outcomes,which suggests that MPS method is particularly effective for modeling complex,non-linear fluid *** the fluid’s response to excitation at its natural frequency is simulated,showcasing vigorous sloshing and rotational *** analyses of the fluid motion are conducted by drawing streamline diagrams,velocity vector diagrams,and vorticity *** fluid’s motion response is explored using both time-domain and frequency-domain curves of the fluid centroid,as well as the sloshing force.

关键词： Moving particle semi-implicit(MPS)method spherical tank liquid sloshing model experiment

High toughness and CMAS resistance of REAlO_(3)/RE_(2)Zr_(2)O_(7)(RE=La,Nd,Sm,Eu,Gd,and Dy)composites with eutectic composition for thermal barrier coatings

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Journal of Advanced Ceramics 2024年第6期13卷 800-809页

作者： Zijian Zhang Jian Sun Guanghua Liu yi Han Wei Liu yi Li Wei wang Xiangyang Liu Peng Zhang Wei Pan Chunlei wan State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China China United Gas Turbine Technology Co. Ltd.Beijing 100015China College of Mathematics and Physics Beijing University of Chemical TechnologyBeijing 100029China College of Materials Science and Engineering Beijing University of TechnologyBeijing 100124China

Although rare earth zirconates(RE_(2)Zr_(2)O_(7))have garnered attention as viable candidates for thermal barrier coatings(TBCs),they suffer from low fracture toughness and accelerated calcium–magnesium–alumina–silicate(CMAS)melt corrosion at high service temperatures,which impedes their practical *** this work,we developed a series of REAlO_(3)/RE_(2)Zr_(2)O_(7)(RE=La,Nd,Sm,Eu,Gd,and Dy)composites with a eutectic composition that not only significantly enhanced the fracture toughness by more than 40%relative to that of RE_(2)Zr_(2)O_(7)but also exhibited improved resistance to CMAS *** increase in toughness arises from multiple mechanisms,such as ferroelastic toughening,fine-grain strengthening,and residual stress toughening,all of which trigger more crack defects and energy ***,the CMAS penetration depth of the REAlO_(3)/RE_(2)Zr_(2)O_(7)composites is approximately 36%lower than that of RE_(2)Zr_(2)O_(7).Al–O constituents in composites can capture CaO,SiO_(2),and MgO in CMAS melts and increase their viscosity,resulting in enhanced CMAS corrosion *** thermophysical properties of the REAlO_(3)/RE_(2)Zr_(2)O_(7)composites were also investigated,and their coefficient of thermal expansion and thermal conductivity are comparable to those of 7–8 wt%Y_(2)O_(3)partially stabilized ZrO2(YSZ),indicating their potential as TBC materials.

关键词： fracture toughness thermal property calcium-magnesium-alumina-silicate(CMAS)corrosion REAlO_(3)/RE_(2)Zr_(2)O_(7) eutectic composition

Nanoscale“precision strike”:Tumor microenvironment-responsive smart micelles for efficient targeted drug delivery

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Nano Research 2024年第9期17卷 8360-8367页

作者： Dong wan Yarong Song Xiujuan Lu Yanfeng Huang Jianxin Zhang Yonghui Liu yi Liu Jie Pan School of Chemistry Tiangong UniversityTianjin 300387China School of Chemical Engineering and Technology Tiangong UniversityTianjin 300387China

To address the limitations of conventional nanotechnology-based drug delivery systems,this work developed enzyme and reduction dual-responsive polymeric *** micelles were synthesized with copolymers composed of TPGS_(3350)-PVGLIG-DOX(TPD)and FA-SS-DOX(FSD),which endow them with tumor-targeted drug delivery ***_(3350)contributes to extending the circulation of micelles in body,augmenting their accumulation in tumor tissues via the enhanced permeability and retention(EPR)*** localized the tumor site,matrix metalloproteinase 2(MMP2)cleaves the PVGLIG peptide moiety within the micelles,thereby releasing TPGS_(3350)and exposing the targeting ligand of *** approach enables the subsequent internalization of the micelles by tumor cells through folate receptor-mediated *** internalization,the high intracellular concentration of glutathione(GSH)triggers the reduction of the disulfide bond within the FA-SS-DOX,leading to the release of the anticancer-drug doxorubicin(DOX),which promotes apoptosis in the tumor cells and enhances the efficacy of chemotherapy.

关键词： cancer peptide micelle dual-responsive folate