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A new liquid membrane diffusion model for characterizing the adsorption kinetics of europium by using a continuous measurement of adsorption platform

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Nuclear Science and Techniques 2024年第1期35卷 59-72页

作者： hao-Qi yu Tao yu Jian-Hua Ye State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China CGN Cangnan Nuclear Power Co. Ltd.Cangnan 325800China Jiangxi Province Key Laboratory of Polymer Micro/Nano Manufacturing and devices East China University of TechnologyNanchang 330013China School of Nuclear Science and Engineering East China University of TechnologyNanchang 330013China

To explore the kinetic adsorption under continuous and nonequilibrium states, an integration of continuous measurement and adsorption platform kinetics method was proposed, which was initially called the ICM-AP kinetics method, and a corresponding kinetic adsorption experimental method was developed. Adsorption experiments of europium(Eu) on Ca-bentonite,Na-bentonite, and the D231 cation exchange resin were performed using the ICM-AP kinetics method and continuous measurements. Because the kinetic experimental results observed in this study were different from those of traditional batch adsorption data, pseudo-first-order or pseudo-second-order kinetic models were unsuitable for fitting the experimental ***, a liquid membrane diffusion(LMD) model was developed based on the assumption of simultaneous adsorption/desorption to discuss the mechanism of kinetic adsorption. The kinetic adsorption mechanism was also studied by using *** results indicated that the proposed adsorption model can fit the experimental data more suitably, and the adsorption/desorption behaviors of Eu on bentonite and the D231 resin were simultaneously observed, suggesting that the adsorption kinetics of Eu(Ⅲ) was mainly dominated by hydrated Eu(Ⅲ) ions on the liquid membrane.

关键词： ICM-AP method LMD model Adsorption mechanism Eu(Ⅲ)

Effects of precipitates and inclusions on the fracture toughness of hot rolling X70 pipeline steel plates

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International Journal of Minerals,Metallurgy and Materials 2012年第9期19卷 805-811页

作者： Mai-wen Zhou hao yu School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

In order to investigate the fracture toughness, crack tip opening displacement （CTOD） experiments were conducted on two X70 pipeline steel plates with different rolling processes. Atter the experiments, optical microscopy （OM）, scanning electron microscopy （SEM） and transmission electron microscopy （TEM） were employed to observe the microstructure and fracture morphology. The effects of precipi- tates on the fracture toughness and the crack initiation mechanism induced by inclusions were analyzed. The CTOD result shows that the steel with a lower finishing cooling temperature has a higher fracture toughness. Inchisiom with different shapes and two kinds of precipi- tates with different sizes were observed. It can be concluded that precipitates with different sizes have different effects and mechanisms on the fracture toughness. Distinguished fi＇om the earlier researches, inclusions enriched in silicon can be also served as the crack initiation.

关键词： pipeline steel crack propagation precipitates inclusions fracture toughness

Non-parametric reconstruction of growth index via Gaussian processes

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Science China(Physics,Mechanics & Astronomy) 2019年第9期62卷 110-119页

作者： Zhao-yu Yin hao Wei School of Physics Beijing Institute of Technology

The accelerated cosmic expansion could be due to dark energy within general relativity(GR), or modified gravity. Differentiating between them using both the expansion history and growth history has attracted considerable attention. In the literature, the growth index γ has been found useful to distinguish these two scenarios. This work aims to consider the non-parametric reconstruction of the growth index γ as a function of redshift z from the latest observational data as of July 2018 via Gaussian processes. We found that f(R) theories and dark energy models within GR(especially ΛCDM) are inconsistent with the results in the moderate redshift range far beyond 3σ confidence level. A modified gravity scenario different from f(R) theories is favored. However, these results can also be due to other non-trivial possibilities in which dark energy models within GR(especially ΛCDM) and f(R) theories may still survive. In all cases, our results suggest that new physics is required.

关键词： cosmology dark energy modified gravity growth index Gaussian processes

Lexicon-Augmented Cross-Domain Chinese Word Segmentation with Graph Convolutional Network

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Chinese Journal of Electronics 2022年第5期31卷 949-957页

作者： yu hao HUANG Kaiyu WANG yu HUANG degen School of Computer Science and Technology Dalian University of Technology School of Foreign Languages Dalian University of Technology

Existing neural approaches have achieved significant progress for Chinese word segmentation(CWS). The performances of these methods tend to drop dramatically in the cross-domain scenarios due to the data distribution mismatch across domains and the out of vocabulary words problem. To address these two issues,proposes a lexicon-augmented graph convolutional network for cross-domain CWS. The novel model can capture the information of word boundaries from all candidate words and utilize domain lexicons to alleviate the distribution gap across domains. Experimental results on the cross-domain CWS datasets(SIGHAN-2010 and TCM)show that the proposed method successfully models information of domain lexicons for neural CWS approaches and helps to achieve competitive performance for crossdomain CWS. The two problems of cross-domain CWS can be effectively solved through various interactions between characters and candidate words based on ***, experiments on the CWS benchmarks(Bakeoff-2005) also demonstrate the robustness and efficiency of the proposed method.

关键词： cross-domain CWS datasets candidate words neural CWS approaches vocabulary words problem text analysis vocabulary convolutional neural nets domain lexicons natural language processing lexicon-augmented cross-domain Chinese word segmentation graph neural networks lexicon-augmented graph convolutional network learning (artificial intelligence) cross-domain scenarios word processing word boundaries

NGP_G-STABILITY OF LINEAR MULTISTEP METHODS FOR SYSTEMS OF GENERALIZED NEUTRAL deLAY DIFFERENTIAL EQUATIONS

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Applied Mathematics and Mechanics(English Edition) 2001年第7期22卷 827-835页

作者： CONG yu-hao(丛玉豪) department of Mathematics Shanghai Normal University Shanghai 200234 P R China

The stability analysis of linear multistep methods for the numerical solutions of the systems of generalized neutral delay differential equations is discussed. The stability behaviour of linear multistep methods was analysed for the solution of the generalized system of linear neutral test equations, After the establishment of a sufficient condition for asymptotic stability of the solutions of the generalized system, it is shown that a linear multistep method is NGP(G)-stable if and only if it is A-stable.

关键词： generalized neutral delay differential system asymptotic stability linear multistep methods NGP(G)-stability

Aircraft detection for HR SAR Images in Non-homogeneous Background Using GGMD-Based Modeling

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Chinese Journal of Electronics 2019年第6期28卷 1271-1280页

作者： HU hao HUANG Lanqing yu Wenxian Shanghai Key Laboratory of Intelligent Sensing and Recognition Shanghai Jiao Tong University

In the problem of aircraft detection for High resolution(HR) Synthetic aperture radar(SAR)images, the background areas commonly contain multiple land cover types, such as runways and grassland. The conventional Constant false alarm rate(CFAR) detection in these non-homogeneous backgrounds with homogeneous assumption leads to unreliable detection results. This paper constructs a one-stage detection method based on the Generalized gamma mixture distribution(GGMD),which is regarded as a competitive and applicable model for combining the advantages of the Generalized gamma distribution(GGD) and the Finite mixture model(FMM).In order to evaluate the availability of the proposed algorithm, HR SAR images for aircraft detection from different product types and with various resolutions are examined. Compared with the CFAR algorithms based on the Gamma distribution, the GGD, and the gamma mixture distribution, the proposed algorithm demonstrates its availability and effectiveness for aircraft detection in HR SAR images in non-homogeneous background.

关键词： Constant false alarm rate(CFAR) Generalized gamma mixture distribution(GGMD) Expectation maximization(EM) Synthetic aperture radar(SAR)

de-noising of radiation pressure signal generated by bubble oscillation based on ensemble empirical mode decomposition

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Journal of Hydrodynamics 2022年第5期34卷 849-863页

作者： Xiang-hao Zheng yu-ning Zhang Key Laboratory of Power Station Energy Transfer Conversion and System(Ministry of Education) School of EnergyPower and Mechanical EngineeringNorth China Electric Power UniversityBeijing102206China

The radiation pressure signals generated by the bubble oscillation are often utilized to recognize the characteristics of the target objects in many ***,these signals are easily contaminated by complex background *** order to accurately extract the effective components of the radiation pressure signal generated by the bubble oscillation,this paper proposes a de-noising procedure for the radiation pressure signal,based on the ensemble empirical mode decomposition(EEMD),the autocorrelation function and the modified wavelet soft-threshold de-noising *** order to verify the effectiveness of the procedure,the typical radiation pressure signal generated based on the Keller-Miksis model under the acoustic excitation is employed for the subsequent de-noising *** results of the qualitative analysis show that the amplitude and the period of the bubble oscillation can be clearly observed in the time-domain diagram of the de-noised signal based on the *** the quantitative analysis,the de-noised signal based on the EEMD has better performance with higher signal-to-noise ratio(SNR),smaller root-mean-square error,and larger correlation coefficient than that based on the wavelet transform(WT)and the empirical mode decomposition(EMD).Furthermore,with the increase of the complexity of the radiation pressure signal(e.g.,the increase of the dimensionless pressure amplitude of the acoustic wave and the decrease of the SNR of the input signal),the above three evaluation indexes of the de-noised signal based on the EEMD are all better than those based on the other two *** the signal is more complex,the de-noising capabilities of the WT,the EMD are greatly reduced,but the EEMD can still maintain the good de-noising capability,which shows the superiority of the signal de-noising procedure proposed in the present paper.

关键词： Radiation pressure cavitation bubble oscillation signal de-noising ensemble empirical mode decomposition(EEMD) autocorrelation function wavelet soft-threshold de-noising

Biomimetic nanomedicine toward personalized disease theranostics

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Nano Research 2021年第8期14卷 2491-2511页

作者： Huisong hao yu Chen Meiying Wu School of Pharmaceutical Sciences(Shenzhen) Sun Yat-sen UniversityShenzhen 518107China School of Life Sciences Shanghai UniversityShanghai 200444China

despite nanoparticle-based drug delivery systems have aroused broad research interest in the biomedical fields,the rising challenges such as easy recognition by the immune system and low accumulation in diseased sites significantly hinder their further clinical *** wrapped in cell membrane have emerged as a distinctive strategy to overcome these limitations due to the superior marriage of natural cell membrane and artificial nanomaterials,which endow them with prominent advantages in disease diagnosis and treatment,such as targeted drug transport,prolonged drug half-life,and diminished immunogenicity and *** this review,we mainly highlight and discuss the evolving progresses and advantages of cell membrane-based biomimetic nanosystems in the detection and treatment of various diseases over the past five years,including oncology,bacterial infections,brain diseases,and inflammatory diseases,which would benefit researchers in better and comprehensively understanding the complicated microenvironment of diseases and developing personalized biomimetic nanomedicines for different *** current challenges and potential opportunities for the future clinical translation of cell membrane coating nanotechnology are also covered.

关键词： diseases theranostics personalized nanomedicine biomimetic

Multi-Robot Cooperative Localization:Time-Varying Unobservable Subspace Analysis and Consistent Algorithm design

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Journal of Systems Science & Complexity 2024年第5期37卷 1937-1955页

作者： hao Ning HE Fenghua YAO yu School of Astronautics Harbin Institute of TechnologyHarbin 150000China

This paper investigates the problem of cooperative localization(CL)for a multi-robot system(MRS)under dynamic measurement topology,which involves a group of robots collectively estimating their poses with respect to a common reference frame using ego-motion measurements and robot-to-robot relative *** authors provide a theoretical analysis of the time-varying unobservable subspace and propose a consistent cooperative localization ***,the authors introduce the relative measurement graph(RMG)to represent the relative pose measurements obtained by the MRS at each ***,the authors derive the local observability matrix over a time *** equivalent relationship is established between the local observability matrix and the spectral matrices of the ***,the authors present a method for constructing the unobservable subspace based on the RMG under different topology *** on this analysis,the authors design a consistent cooperative localization algorithm that satisfies the constraints of the time-varying unobservable *** analytical optimal solution is derived for the constrained optimization *** Carlo numerical simulations are conducted to demonstrate the consistency and accuracy of the proposed method.

关键词： Consistency cooperative localization multi-robot system null space relative measurement graph time-varying unobservable subspace