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Robust Space-Time Ada.tive Track-Before-Detect Algorithm Based on Persymmetry and Symmetric Spectrum

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Journal of Beijing Institute of Technology 2024年第1期33卷 65-74页

作者： Xiaojing Su da.Xu Dongsheng Zhu Zhixun ma Institute of Acoustics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Underwater monopulse space-time ada.tive track-before-detect method,which combines space-time ada.tive detector(STAD)and the track-before-detect algorithm based on dynamic programming(DP-TBD),denoted as STAD-DP-TBD,can effectively detect low-speed weak ***,due to the complexity and variability of the underwater environment,it is difficult to obtain sufficient seconda.y da.a,resulting in a serious decline in the detection and tracking performance,and leading to poor robustness of the *** this paper,based on the ada.tive matched filter(AMF)test and the RAO test,underwater monopulse AMF-DP-TBD algorithm and RAO-DP-TBD algorithm which incorporate persymmetry and symmetric spectrum,denoted as PSAMF-DP-TBD and PS-RAO-DP-TBD,are proposed and compared with the AMF-DP-TBD algorithm and RAO-DP-TBD algorithm based on persymmetry array,denoted as P-AMF-DP-TBD and *** simulation results show that the four methods can work normally with sufficient seconda.y da.a and slightly insufficient seconda.y da.a,but when the seconda.y da.a is severely insufficient,the P-AMF-DP-TBD and P-RAO-DP-TBD algorithms has failed while the PSAMF-DP-TBD and PS-RAO-DP-TBD algorithms still have good detection and tracking capabilities.

关键词： space-time ada.tive detection track before detect robustness persymmetric property symmetric spectrum AMF test RAO test

A Hybrid Approach for Predicting the Remaining Useful Life of Bearings Based on the RReliefF Algorithm and Extreme Learning machine

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 1405-1427页

作者： sen-Hui Wang Xi Kang Cheng Wang Tian-Bing ma Xiang He Ke Yang School of Mechatronics Engineering Anhui University of Science and TechnologyHuainan232001China Institute of Energy Hefei Comprehensive National Science CenterHefei230031China

Accurately predicting the remaining useful life(RUL)of bearings in mining rotating equipment is vital for mining *** research aims to distinguish the features associated with the RUL of bearings and propose a prediction model based on these selected *** study proposes a hybrid predictive model to assess the RUL of rolling element *** proposed model begins with the pre-processing of bearing vibration signals to reconstruct sixty time-domain *** hybrid model selects relevant features from the sixty time-domain features of the vibration signal by adopting the RReliefF feature selection ***,the extreme learning machine(ELM)approach is applied to develop a predictive model of RUL based on the optimal *** model is trained by optimizing its parameters via the grid search *** training da.asets are adjusted to make them most suitable for the regression model using the cross-valida.ion *** proposed hybrid model is analyzed and valida.ed using the vibration da.a taken from the public XJTU-SY rolling element-bearing *** comparison is constructed with other traditional *** experimental test results demonstrated that the proposed approach can predict the RUL of bearings with a reliable degree of accuracy.

关键词： Bearing degrada.ion remaining useful life estimation RReliefF feature selection extreme learning machine

Physics of cavitation near particles

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Journal of Hydrodynamics 2024年第1期36卷 102-118页

作者： Jia-xin Yu Xiao-yu Wang Jun-wei Shen Jin-sen Hu Xiang-qing Zhang da.qing He Yu-ning Zhang Key Laboratory of Power Station Energy Transfer Conversion and System(Ministry of Education) School of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBeijing102206China

The combined effect of cavitation and silt abrasion presents a great challenge and threat to secure the operation and the efficiency of hydraulic machineries working in sediment-laden *** present paper critically reviews the current research progress on the interaction mechanisms of the bubbles and the ***,the analytical models including bounda.y treatment methods for predicting the jet dynamics of the bubble collapse near particles are ***,the bubble collapsing dynamics,jet dynamics and shock wave characteristics near particles are revealed both experimentally and ***,the bubble-particle-wall system is investigated with a focus on microjets.

关键词： Cavitation bubble particle jet shock wave

Cancer organoids:A platform in basic and translational research

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Genes & Diseases 2024年第2期11卷 614-632页

作者： Xin ma Qin Wang Guozheng Li Hui Li Shouping Xu da.Pang Department of Breast Surgery Harbin Medical University Cancer HospitalHarbinHeilongjiang 150081China Sino-Russian Medical Research Center Harbin Medical University Cancer HospitalHarbinHeilongjiang 150081China Heilongjiang Academy of Medical Sciences HarbinHeilongjiang 150086China Department of Pharmacology (The State-Province Key Laboratories of Biomedicine-Pharmaceutics of China) College of Pharmacy of Harbin Medical UniversityHarbinHeilongjiang 150086China

An accumulation of previous work has established organoids as good preclinical models of human tumors,facilitating translation from basic research to clinical *** are changing the paradigm of preclinical cancer research because they can recapitulate the heterogeneity and pathophysiology of human cancers and more closely approximate the complex tissue environment and structure found in clinical tumors than in vitro cell lines and animal ***,the potential applications of cancer organoids remain to be comprehensively *** the review,we firstly describe what is currently known about cancer organoid culture and then discuss in depth the basic mechanisms,including tumorigenesis and tumor metastasis,and describe recent advances in patient-derived tumor organoids(PDOs)for drug screening and immunological ***,the present challenges faced by organoid technology in clinical practice and its prospects are *** review highlights that organoids may offer a novel therapeutic strategy for cancer research.

关键词： Drug assays Immunotherapy Mechanism research Organoids Precision medicine

Effect of Mn content on microstructure and properties of AlCrCuFeMnx high-entropy alloy

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China Foundry 2024年第2期21卷 147-158页

作者： Ning Wang Kai ma Qiu-da.Li Yu-dong Yuan Yan-chun Zhao Li Feng School of materials Science and Engineering Lanzhou University of TechnologyLanzhou 730050China State Key Laboratory of Advanced Processing and Reuse of Nonferrous Metals Lanzhou 730050China CNNC Nuclear Power Operation and management Co. Ltd.Haiyan 314300ZhejiangChina

AlCrCuFeMnx(x=0,0.5,1,1.5,and 2)high-entropy alloys were prepared using the vacuum arc melting *** microstructure and mechanical properties of AlCrCuFeMnxwere analyzed and tested by XRD,SEM,TEM,nanoindentation,and electronic universal *** results indicate that the AlCrCuFeMnxhigh-entropy alloy exhibits a dendritic structure,consisting of dendrites with a BCC structure,interdendrite regions with an FCC structure,and precipitates with an ordered BCC structure that form within the ***(Mn)has a strong affinity for dendritic,interdendritic,and precipitate structures,allowing it to easily enter these *** an increase in Mn content,the size of the precipitated nanoparticles in the dendritic region initially increases and then ***,the area fraction initially decreases and then ***,the alloy’s strength and wear resistance decrease,while its plasticity *** Al Cr Cu Fe Mn1.5alloy boasts excellent mechanical properties,including a hardness of 360 HV and a wear rate of 2.4×10^(-5)mm^(3)·N^(-1)·mm^(-1).It also exhibits impressive yield strength,compressive strength,and deformation rates of 960 MPa,1,700 MPa,and 27.5%,respectively.

关键词： high-entropy alloys microstructure mechanical properties wear resistance strengthening mechanisms

CAOSA-extracted lignin improves enzymatic hydrolysis of cellulose

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Green Energy & Environment 2024年第7期9卷 1101-1111页

作者： sen ma Zheng Li Jonathan Sperry Xing Tang Yong Sun Lu Lin Jian Liu Xianhai Zeng College of Energy State Key Laboratory of Physical Chemistry of Solid Surfaces Xiamen University Fujian Engineering and Research Centre of Clean and High-valued Technologies for Biomass Xiamen Key Laboratory of Clean and High-valued Utilization of Biomass Centre for Green Chemical Science University of Auckland

The conversion of biomass into sugar platform compounds is very important for the biorefinery industry. Pretreatment is essential to the biomass of the sugar platform, however, the lignin obtained by pretreatment, as a key part of lignocellulose, generally has a passive effect on the enzymatic hydrolysis of cellulose into sugars. In this study, p-TsOH(p-toluenesulfonic acid), DES(Deep eutectic solvent) and CAOSA(cooking with active oxygen and solid alkali) pretreatment ways were used to fraction lignin from bamboo biomass. After CAOSA treatment, the hydrolysis efficiency of the pulp was 95.57%. Moreover, the effect of different treatment methods on lignin properties was studied and the promotion effect of lignin was investigated by adding it to the cellulose enzymatic hydrolysis system. In this work, the results showed that CAOSA-extracted lignin with lower ?(1.31–1.25) had a better adsorption effect on the enzyme protein. p-TsOH-extracted lignin with a larger S/G ratio enhanced the inhibition of enzymatic hydrolysis. In addition, the presence of-COOHs in lignin could reduce its inhibitory effect on cellulose saccharification.

关键词： Biomass pretreatment CAOSA Cellulose hydrolysis Lignin Enzyme

Efficient privacy-preserving federated learning under dishonest-majority setting

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Science China(Information Sciences) 2024年第5期67卷 323-324页

作者： Yinbin MIAO da.KUANG Xinghua LI Tao LENG Ximeng LIU Jianfeng ma School of Cyber Engineering Xidian University Intelligent Policing Key Laboratory of Sichuan Province Sichuan Police College Institute of Information Engineering Chinese Academy of Sciences School of Cyber Security University of Chinese Academy of Sciences Key Laboratory of Information Security of Network Systems Fuzhou University

Federated learning(FL) is an emerging distributed learning paradigm that solves the problem of isolated da.a by jointly learning the global model through distributed ***, recent studies have shown that FL may not always guarantee sufficient privacy preservation, this is mainly because the model parameters(e.g., weights or gradients)may leak sensitive information to malicious adversaries.

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Optical responses of metallic plasmonic arrays under the localized excitation

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Nano Research 2024年第3期17卷 1571-1577页

作者： sen Yan Hao ma Yi-Fan Bao maofeng Cao Chuan Liu Kaifeng Zhang Xiaowei Wu Jianbo He Xiang Wang Bin Ren State Key Laboratory of Physical Chemistry of Solid Surfaces Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Innovation Laboratory for Sciences and Technologies of Energy materials of Fujian Province(IKKEM) Xiamen 361005China Research&Development Group HitachiLtd.Yokohama 244-0817KanagawaJapan Department of Electronic Science and Engineering Kyoto UniversityKyoto 615-8510Japan

The metallic plasmonic array that can support both propagating surface plasmon polaritons(PSPPs)and localized surface plasmon resonance(LSPR)possesses rich optical properties and remarkable optical performance,making it a powerful platform for applications in photonics,chemistry,and *** practical applications,the excitation spot is usually smaller than the area of metal *** is thus imperative to address“how many array units are enough?”towards a rational design of plasmonic ***,we employed focused ion beam(FIB)to precisely fabricate a series of plasmonic array structures with increased unit *** utilizing photoluminescence(PL)and surface-enhanced Raman spectroscopy(SERS),we found that the array units outside the excitation spot still have a significant impact on the optical response within the *** with the numerical simulation,we found that the bounda.y of the finite array leads to the loss of PSPP outside the excitation point,which subsequently affects the coupling of PSPP and LSPR in the excitation spot,leading to variations in PL and SERS *** on the findings,we further tuned the LSPR mode of the metal arrays by electrodeposition to obtain strong near-field enhancement without any influence on the PSPP *** work advances the understanding of near-field and far-field optical behavior in finite-size array structures and provides guida.ce for designing highly-efficient photonic devices.

关键词： plasmonic periodic array finite-size effects da.k field scattering surface-enhanced Raman spectroscopy(SERS)

An extended state observer with adjustable bandwidth for measurement noise

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Journal of Systems Engineering and Electronics 2024年第1期35卷 233-241页

作者： ZHANG Shihua QI Xiaohui YANG sen Shijiazhuang Campus Army Engineering University of PLAShijiazhuang 050053China

In this paper,a bandwidth-adjustable extended state observer(ABESO)is proposed for the systems with measurement *** is known that increasing the bandwidth of the observer improves the tracking speed but tolerates noise,which conflicts with observation ***,we introduce a bandwidth scaling factor such that ABESO is formulated to a 2-degree-of-freedom *** observer gain is determined and the bandwidth scaling factor adjusts the bandwidth according to the tracking *** the tracking error decreases,the bandwidth decreases to suppress the noise,otherwise the bandwidth does not *** is proven that the error dynamics are bounded and converge in finite *** relationship between the upper bound of the estimation error and the scaling factor is *** the scaling factor is less than 1,the ABESO has higher estimation accuracy than the linear extended state observer(LESO).Simulations of an uncertain nonlinear system with compound disturbances show that the proposed ABESO can successfully estimate the total disturbance in noisy *** mean error of total disturbance of ABESO is 15.28% lower than that of LESO.

关键词： extended state observer(ESO) boundedness and convergence adjustable bandwidth measurement noise