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On the Fourth Power Mean of the Generalized Quadratic Gauss Sums

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Acta Mathematica Sinica,English Series 2018年第6期34卷 1037-1049页

作者： Wen peng ZhanG Xin lin School of Mathematics Northwest University

The main purpose of this paper is to use elementary methods and properties of the classical Gauss sums to study the computational problem of one kind of fourth power mean of the generalized quadratic Gauss sums mod q ... 详细信息

关键词： The generalized quadratic Gauss sums the fourth power mean analytic method computational formula

Two New Gallotannins from Pistacia weinmannifolia

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Chinese Chemical Letters 2000年第1期11卷 53-56页

作者： Ai Jun HOU Li Yan peng Yan Ze LIU Zhong Wen lin han Dong SUN Laboratory of phytochemistry Kunming Institute of BotanyChinese Academy of SciencesKunming 650204 Department of Phytochemistry Henan College of Traditional Chinese MedicieZhengzhou 450003

Two new gallotannins, pistafolins A (1) and B (2), were isolated from the leaf extract of Pistacia weinmannifolia. Their structures were determined by spectral methods.

关键词： Pistacia weinmannifolia Anacardiaceae gallotannin pistafolin A pistafolin B

Optimization of remanufacturing process routes oriented toward eco-efficiency

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Frontiers of Mechanical Engineering 2019年第4期14卷 422-433页

作者： Hong peng han WANG Daojia CHEN Key Laboratory of Metallurgical Equipment and Control Technology Wuhan University of Science and TechnologyWuhan 430081China Hubei Key Laboratory of Mechanical Transmission and Manufacturing Engineering Wuhan University of Science and TechnologyWuhan 430081China Academy of Green Manufacturing Engineering Wuhan University of Science and TechnologyWuhan 430081China

Remanufacturing route optimization is crucial in remanufacturing production because it exerts a considerable impact on the eco-efficiency(i.e.,the best link between economic and environmental benefits)of ***,an optimization model for remanufacturing process routes oriented toward eco-efficiency is *** this model,fault tree analysis is used to extract the characteristic factors of used *** ICAM definition method is utilized to design alternative remanufacturing process routes for the used ***,an eco-efficiency objective function model is established,and simulated annealing(SA)particle swarm optimization(PSO)is applied to select the manufacturing process route with the best *** proposed model is then applied to the remanufacturing of a used helical cylindrical gear,and optimization of the remanufacturing process route is realized by MATLAB *** proposed model’s feasibility is verified by comparing the model’s performance with that of standard SA and PSO.

关键词： remanufacturing process route optimization eco-efficiency simulated particle swarm optimization algorithm IDEF0

Introduction of parameterized sea ice drag coefficients into ice free-drift modeling

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Acta Oceanologica Sinica 2016年第1期35卷 53-59页

作者： LU peng LI Zhijun han Hongwei Laboratory of Coastal and Offshore Engineering Dalian University of Technology

Many interesting characteristics of sea ice drift depend on the atmospheric drag coefficient （Ca） and oceanic drag coefficient （Cw）. Parameterizations of drag coefficients rather than constant values provide us a way to look insight into the dependence of these characteristics on sea ice conditions. In the present study, the parameterized ice drag coefficients are included into a free-drift sea ice dynamic model, and the wind factor a and the deflection angle θ between sea ice drift and wind velocity as well as the ratio of Ca to Cw are studied to investigate their dependence on the impact factors such as local drag coefficients, floe and ridge geometry. The results reveal that in an idealized steady ocean, Ca/Cw increases obviously with the increasing ice concentration for small ice floes in the marginal ice zone, while it remains at a steady level （0.2-0.25） for large floes in the central ice zone. The wind factor a increases rapidly at first and approaches a steady level of 0.018 when A is greater than 20%. And the deflection angle ~ drops rapidly from an initial value of approximate 80° and decreases slowly as A is greater than 20% without a steady level like a. The values of these parameters agree well with the previously reported observations in Arctic. The ridging intensity is an important parameter to determine the dominant contribution of the ratio of skin friction drag coefficient （Cs＇/Cs） and the ratio of ridge form drag coefficient （Cr＇/Cr） to the value of Ca/Cw, a, and 8, because of the dominance of ridge form drag for large ridging intensity and skin friction for small ridging intensity among the total drag forces. Parameterization of sea ice drag coefficients has the potential to be embedded into ice dynamic models to better account for the variability of sea ice in the transient Arctic Ocean.

关键词： sea ice drag coefficient parameterization free drift modeling

Swin-PAFF: A SAR Ship Detection Network with Contextual Cross-Information Fusion

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Computers, Materials & Continua 2023年第11期77卷 2657-2675页

作者： Yujun Zhang Dezhi han peng Chen School of Information Engineering Shanghai Maritime UniversityShanghai201306China

Synthetic Aperture Radar(SAR)image target detection has widespread applications in both military and civil ***,SAR images pose challenges due to strong scattering,indistinct edge contours,multi-scale representation,sparsity,and severe background interference,which make the existing target detection methods in low *** address this issue,this paper proposes a multi-scale fusion framework(Swin-PAFF)for SAR target detection that utilizes the global context perception capability of the Transformer and the multi-layer feature fusion learning ability of the feature pyramid structure(FPN).Firstly,to tackle the issue of inadequate perceptual image context information in SAR target detection,we propose an end-to-end SAR target detection network with the Transformer structure as the ***,we enhance the ability of the Swin Transformer to acquire contextual features and cross-information by incorporating a Swin-CC backbone network model that combines the Spatial Depthwise Pooling(SDP)module and the self-attentive ***,we design a cross-layer fusion neck module(PAFF)that better handles multi-scale variations and complex situations(such as sparsity,background interference,etc.).Our devised approach yields a noteworthy AP@0.5:0.95 performance of 91.3%when assessed on the HRSID *** application of our proposed technique has resulted in a noteworthy advancement of 8%in the AP@0.5:0.95 scores on the HRSID dataset.

关键词： Transformer deep learning SAR object detection ship detection

Mean shift texture surface detection based on WT and COM feature image selection

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第6期7卷 969-975页

作者： han Yan-fang SHI peng-fei Institute of lmage Processing and Pattern Recognition Shanghai Jiao Tong University Shanghai 200030 China

Mean shift is a widely used clustering algorithm in image segmentation. However, the segmenting results are not so good as expected when dealing with the texture surface due to the influence of the textures. Therefore, an approach based on wavelet transform (WT), co-occurrence matrix (COM) and mean shift is proposed in this paper. First, WT and COM are employed to extract the optimal resolution approximation of the original image as feature image. Then, mean shift is successfully used to obtain better detection results. Finally, experiments are done to show this approach is effective.

关键词： Mean shift Wavelet transform (WT) Co-occurrence matrix (COM) Texture defect detection

Optically stimulated luminescence dating of sandy deposits from Gulang county at the southern margin of the Tengger Desert, China

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Journal of Arid Land 2016年第1期8卷 1-12页

作者： peng Jun DONG Zhibao han Fengqing Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Qinghai Institute of Salt Lakes Chinese Academy of Sciences

Aeolian deposits from the deserts in northern China have been used for palaeoenvironmental research to understand aeolian sedimentology and its dynamic connection to past climate conditions. The Tengger Desert in China is sensitive to the waxing and waning of the monsoonal system. In response to past climate change, the southern margin of the Tengger Desert has evolved significantly since the last glacial period. However, previous attempts to date aeolian deposits in this region were mainly based on radiocarbon dating, which has problems when applied to aeolian deposits. Moreover, sedimentary records are limited. Accordingly, past aeolian activity in this desert remains poorly understood. In the present study, we dated sand samples from Gulang county at the southern margin of the Tengger Desert using optically stimulated luminescence (OSL) to understand the history of aeolian activity in this region. Our samples represented well-sorted aeolian sands and sandy loess. Aeolian sands are evidence of dune field buildup and sparse vegetation cover whereas sandy loess is evidence of improved stabilization of sand dunes resulting from ameliorated vegetation cover. Certain samples showed a decline in the equivalent dose (D e ) values when successive integration intervals were applied, which resulted from unstable OSL signals from non-fast components in the initial part of the decay curve. In order to obtain reliable D e estimates, we investigated component-resolved and different background subtraction approaches, and compared the resultant D e estimates. We adopted the early background subtraction method to derive D e values. Luminescence chronologies and sedimentary records indicated that sand dunes accumulation occurred before 10 ka, and sandy loess developed between 9.5 and 7.6 ka when sand dunes were stabilized as a result of increased effective moisture levels. The transition between sand dune mobilization and stabiliza

关键词： OSL dating sandy deposit integration interval selection aeolian activity Tengger Desert

A Class of Spline Curves with Four Local Shape Parameters

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Acta Mathematicae Applicatae Sinica 2017年第4期33卷 979-988页

作者： Yuan-peng ZHU Xu-li han School of Mathematics South China University of Technology School of Mathematics and Statistics Central South University

A class of spline curves with four local shape parameters, which includes the quartic spline curves with three local shape parameters given in han [Xuli han. A class of general quartic spline curves with shape parameters. Comput. Aided Geom. Design, 28：151-163 （2011）], is proposed. Without solving a linear system, the spline curves can be used to interpolate sets of points with C2 continuity partly or entirely. The shape parameters have a predictable adjusting role on the sp[ine curves.

关键词： B-spline curve quartic spline curve interpolation curve shape control shape parameter

Improved Variable Forgetting Factor Proportionate RLS Algorithm with Sparse Penalty and Fast Implementation Using DCD Iterations

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China Communications 2024年第10期21卷 16-27页

作者： han Zhen Zhang Fengrui Zhang Yu han Yanfeng Jiang peng GNSS Research Center Wuhan UniversityWuhan 430072China School of Information Science and Technology Shijiazhuang Tiedao UniversityShijiazhuang 050043China

The proportionate recursive least squares(PRLS)algorithm has shown faster convergence and better performance than both proportionate updating(PU)mechanism based least mean squares(LMS)algorithms and RLS algorithms with a sparse regularization *** this paper,we propose a variable forgetting factor(VFF)PRLS algorithm with a sparse penalty,e.g.,l_(1)-norm,for sparse *** reduce the computation complexity of the proposed algorithm,a fast implementation method based on dichotomous coordinate descent(DCD)algorithm is also *** results indicate superior performance of the proposed algorithm.

关键词： dichotomous coordinate descent proportionate matrix RLS sparse systems variable forgetting factor