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Two-Stage Online Debiased Lasso Estimation and Inference for High-Dimensional Quantile Regression with Streaming Data

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Journal of Systems Science & Complexity 2024年第3期37卷 1251-1270页

作者： peng Yanjin WANG lei School of Statistics and Data Science KLMDASRLEBPS and LPMCNankai UniversityTianjin 300071China

In this paper,the authors propose a two-stage online debiased lasso estimation and statistical inference method for high-dimensional quantile regression(QR)models in the presence of streaming *** the first stage,the authors modify the QR score function based on kernel smoothing and obtain the online lasso smoothed QR estimator through iterative *** estimation process only involves the current data batch and specific historical summary statistics,which perfectly accommodates to the special structure of streaming *** the second stage,an online debiasing procedure is carried out to eliminate biases caused by the lasso penalty as well as the accumulative approximation error so that the asymptotic normality of the resulting estimator can be *** authors conduct extensive numerical experiments to evaluate the performance of the proposed *** experiments demonstrate the effectiveness of the proposed method and support the theoretical *** application to the Beijing PM2.5 Dataset is also presented.

关键词： Adaptive tuning asymptotic normality debiased lasso online updating quantile regres-sion

Revisit of the Faddeev Model in Dimension Two

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Chinese Annals of Mathematics,Series B 2022年第5期43卷 797-818页

作者： Shijie DONG zhen lei SUSTech International Center for Mathematics Department of MathematicsSouthern University of Science and TechnologyShenzhen 518055China School of Mathematical Sciences Shanghai Center for Mathematical SciencesFudan UniversityShanghai 200433China

The Faddeev model is a fundamental model in relativistic quantum field theory used to model elementary particles. The Faddeev model can be regarded as a system of non-linear wave equations with both quasi-linear and semi-linear non-linearities, which is particularly challenging in two space dimensions. A key feature of the system is that there exist undifferentiated wave components in the non-linearities, which somehow causes extra difficulties. Nevertheless, the Cauchy problem in two space dimenions was tackled by lei-Lin-Zhou(2011) with small, regular, and compactly supported initial data, using Klainerman’s vector field method enhanced by a novel angular-radial anisotropic *** the present paper, the authors revisit the Faddeev model and remove the compactness assumptions on the initial data by lei-Lin-Zhou(2011). The proof relies on an improved L2norm estimate of the wave components in Theorem 3.1 and a decomposition technique for non-linearities of divergence form.

关键词： Faddeev model in R^(1+2) Global existence Null condition

Porous garnet as filler of solid polymer electrolytes to enhance the performance of solid-state lithium batteries

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Nano Research 2024年第4期17卷 2663-2670页

作者： Yang Zhang lei Zhang peng Guo Chaoyan Zhang Xiaochuan Ren zhen Jiang Jianjun Song Chuan Shi College of Physics Qingdao UniversityQingdao 266071China Industrial Research Institute of Nonwovens and Technical Textiles College of Textiles and ClothingQingdao UniversityQingdao 266071China Department of Chemistry University of PennsylvaniaPhiladelphiaPA 19104USA

In order to enhance the ionic conductivity of solid polymer electrolytes(SPEs)and their structural rigidity against lithium dendrite during lithium-ion battery(LIB)cycling,we propose porous garnet Li6.4La3Zr2Al0.2O12(LLZO),as the filler to *** porous LLZO with interlinked grains was synthesized via a resol-assisted cationic coordinative co-assembly *** porous structure of LLZO with high specific surface area facilitates the interaction between polymer and filler and provides sufficient entrance for Li^(+)migration into the LLZO ***,the interconnection of LLZO grains forms continuous inorganic pathways for fast Li^(+)migration,which avoid the multiple diffusion for Li^(+)in *** a result,the SPEs with porous LLZO(SPE-PL)show a high ionic conductive of 0.73 mS·cm^(-1) at 30℃ and lithium-ion transference number of *** porous LLZO with uniformly dispersed pores also acts as an ion distributor to regulate ionic *** lithium-symmetrical batteries assembled with SPE-PL show a highly stable Li plating/stripping cycling for nearly 3000 h at 0.1 mA·cm^(-2).The corresponding Li/LiFePO_(4) batteries also exhibit excellent cyclic performance with capacity retention of 75%after nearly 500 *** work brings new insights into the design of conductive fillers and the optimization of SPEs.

关键词： solid polymer electrolytes lithium metal battery porous conductive filler solid state battery

Wave Extraction and Attenuation Performance of An Edinburgh Duck Wave Energy Converter

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China Ocean Engineering 2021年第6期35卷 905-913页

作者： ZHOU Bin-zhen LI Jia-hui ZHANG Heng-ming CHEN Li-fen WANG lei JIN peng School of Civil Engineering and Transportation South China University of TechnologyGuangzhou 510641China College of Shipbuilding Engineering Harbin Engineering UniversityHarbin 150001China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China

Edinburgh Duck wave energy converter(ED WEC)has excellent energy extraction performance and shows a great potential to integrate with other marine *** paper aims to investigate its wave energy extraction performance as a WEC and wave attenuation performance as a protection method for shoreline or marine *** wave and ED WEC interactions in regular waves are modeled using the Star-CCM+software and verified by comparisons with published experimental *** motion response,energy conversion efficiency,and transmission coefficient of the ED WEC with different attack angles,rotation center,and incident wave heights are *** indicate that the ED WEC with an attack angle of 42°and a rotation center of 0.55 m below the mean water line can achieve both good wave energy extraction and wave attenuation *** wave energy extraction and wave attenuation performance of the ED WEC decrease significantly with the increase of wave nonlinearity characterized by the wave *** paper can guide the practical application of the ED WEC at the early stage of design.

关键词： Edinburgh Duck wave energy converter wave energy extraction wave attenuation wave nonlinearity

Single Mode Simulation Calculation of Oscillating Buoy Wave Energy Converter with A Slider

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China Ocean Engineering 2020年第4期34卷 547-557页

作者： XIAO lei YOU Ya-ge WANG zhen-peng ZHANG Ya-qun HUANG Shuo WANG Wen-sheng Guangzhou Institute of Energy Conversion Chinese Academy of SciencesGuangzhou 510640China Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development Guangzhou 510640China Southern Marine Science and Engineering Guangdong Laboratory Guangzhou 511458China Key Laboratory of Renewable Energy Chinese Academy of SciencesGuangzhou 510640China Innovation Academy of South China Sea Ecology and Environmental Engineering Chinese Academy of SciencesGuangzhou 510640China University of Chinese Academy of Sciences Beijing 100049China

This paper presents an oscillating slider wave energy device which is based on a seabed anchoring and uses eagle beak as the *** self-compiled program uses the boundary element theory based on the simple Green’s function to solve the wave forces and hydrodynamic *** the equation of motion,the oscillation of the float and the capture width ratio are obtained by the modal *** influences of the shape of the eagle beak,the angle of the slider and the wave heading on the capture ability of the device are *** to the calculation results and the wave resources in the sea area,the optimal shape of the eagle beak and external damping can be selected to maximize the wave energy capture capability.

关键词： wave energy converter(WEC) Sharp Eagle hydrodynamic calculation eagle beak

Novel high-performance element in the electromagnetic finite-element method——node-edge element

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Journal of Systems Engineering and Electronics 2008年第5期19卷 878-881页

作者： Sheng Xinqing peng zhen Center for Electromagnetic Simulation School of Information Science and Technology Beijing Inst. of Technology Beijing 100081 P. R. China

It is known in the computational electromagnetics （CEM） that the node element has a relative wellconditioned matrix, but suffers from the spurious solution problem; whereas the edge element has no spurious solutions, but usually produces an ill-conditioned matrix. Particularly, when the mesh is over dense, the iterative solution of the matrix equation from edge element converges very slowly. Based on the node element and edge element, a node-edge element is presented, which has no spurious solutions and better-conditioned matrix. Numerical experiments demonstrate that the proposed node-edge element is more efficient than now-widely used edge element.

关键词： node-edge element node element edge element matrix condition number.

Modulating carrier density of the(Ag)_(x)(MoO_(3))_(y)system to enhance SERS:Localized surface plasmon resonance contribution

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Journal of Materiomics 2023年第2期9卷 387-394页

作者： Lin Zhu Zhu Mao peng Li Menglei Xu zhen Meng lei Chen Bing Zhao Stake Key Laboratory of Supramolecular Structure and Materials Jilin UniversityChangchun130012China School of Chemistry and Life Science Advanced Institute of Materials ScienceChangchun University of Technology Changchun130012China Key Laboratory of Functional Materials Physics and Chemistry of the Ministry of Education Jilin Normal UniversityChangchun130103China

Semiconductors typically exhibit long-wavelength LSPR absorption in the infrared region due to lower carrier *** the carrier density of semiconductors and blue-shifting their LSPR absorption to the visible and near-infrared region has always been a great ***,we discussed how the controllable carrier of(Ag)x(MoO_(3))y composite influences the LSPR based on SERS test and UVeViseNIR absorption *** were surprised to find that the LSPR absorption wavelength can be easily tuned from 950 to 735 nm by changing the sputtering power of MoO_(3)of the(Ag)x(MoO_(3))_(y)*** shows that LSPR can be precisely adjusted by increasing the semiconductor content and even the carrier *** addition,the carrier density was measured by Hall effect to investigate the SERS intensity change caused by electromagnetic(EM)enhancement,and obtain the relationship between the *** findings of this work provide an idea for tunable LSPR and the research of EM contributions to SERS.

关键词： Carrier density Localized surface plasmon resonance Semiconductor Electromagnetic Surface-enhanced Raman scattering

Multitemporal UAV-based photogrammetry for landslide detection and monitoring in a large area:a case study in the Heifangtai terrace in the Loess Plateau of China

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Journal of Mountain Science 2020年第8期17卷 1826-1839页

作者： XU Qiang LI Wei-le JU Yuan-zhen DONG Xiu-jun peng Da-lei State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China

With high spatial resolution,on-demand-flying ability,and the capacity for obtaining threedimensional measurements,unmanned aerial vehicle(UAV)photogrammetry is widely used for detailed investigations of single landslides,but its effectiveness for landslide detection and monitoring in a large area needs to be *** Heifangtai terrace in the Loess Plateau of China is a loess terrace that is extremely susceptible to irrigation-induced loess *** paper used UAV-based photogrammetry for a series of highresolution images spanning over 30 months for landslide detection and monitoring of the terrace with an area of 32 km^*** and evenly distributed ground control points were established and measured to ensure the high accuracy of the photogrammetry *** structure-from-motion(Sf M)technique was used to convert overlapping images into orthographic images,3D point clouds,digital surface models(DSMs)and mesh *** multitemporal differential mesh models,landslide vertical movements and potential landslides were detected and *** results indicate that a combination of UAV-based orthophotos and differential mesh models can be used for flexible and accurate detection and monitoring of potential loess landslides in a large area.

关键词： Unmanned Aerial Vehicle Loess Plateau Landslide detection Landslide monitoring Differential mesh model Vertical movement

Neural network study of the nuclear ground-state spin distribution within a random interaction ensemble

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Nuclear Science and Techniques 2024年第3期35卷 216-227页

作者： Deng Liu Alam Noor A zhen-zhen Qin Yang lei School of Mathematics and Physics Southwest University of Science and TechnologyMianyang 621010China School of Nuclear Science and Technology Southwest University of Science and TechnologyMianyang 621010China

The distribution of the nuclear ground-state spin in a two-body random ensemble(TBRE)was studied using a general classification neural network(NN)model with two-body interaction matrix elements as input features and the corresponding ground-state spins as labels or output *** quantum many-body system problem exceeds the capability of our optimized NNs in terms of accurately predicting the ground-state spin of each sample within the ***,our NN model effectively captured the statistical properties of the ground-state spin because it learned the empirical regularity of the ground-state spin distribution in TBRE,as discovered by physicists.

关键词： Neural network Two-body random ensemble Spin distribution of nuclear ground state