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Bathymetry inversion using the deflection of the vertical:A case study in South China Sea

Geodesy and Geodynamics 2022年第5期13卷 492-502页

作者： Xiaoyun wan Bo Liu Xiaohong Sui Richard f.Annan Ruijie Hao Yijun Min School of Land Science and Technology China University of Geosciences(Beijing)Beijing 100083China Qian Xuesen Laboratory of Space Technology Beijing 100094China

The deflection of the vertical is one of the essential products of ***,unlike gravity and vertical gravity gradients,it is seldom used in bathymetry *** this study,an algorithm for bathymetry inversion using the deflection of the vertical is ***,we separately derive the formulas for the bathymetry inversion from the north and east components of the vertical deflection and introduce the data *** a local area in the South China Sea is selected as an example to test the *** bathymetry inversion based on gravity anomaly is also conducted for *** the ship-borne depths are the true values,the error standard deviations(STDs)of the bathymetry derived by north and east components of the vertical deflection are 156.64 m and 165.57 m,*** indicates that the north component has a better performance in bathymetry inversion than the east *** inversion results from the combination of both components show a higher accuracy of bathymetry than that from a single *** difference between the error STD of the combination results and that of the gravity anomaly is less than 0.2 *** experiment’s results also show that the precision of the derived bathymetry can be improved if the parameters of linear regression are adjusted according to water *** summary,among the gravity field products used in this study,the gravity anomaly yielded the best performance in the bathymetry ***,since additional data and computation time are required to derive gravity anomalies from altimetric observations,the vertical defections can still be used as supplements,especially in areas where accurate vertical deflections exist.

关键词： Bathymetry Deflection of the vertical Gravity anomaly Satellite altimetry

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Real-time camera tracking using hybrid features in mobile augmented reality

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Science China(Information Sciences) 2015年第11期58卷 211-223页

作者： wanG Weijie wan HuaGen State Key Laboratory of CAD&CG Zhejiang University

Often only simple features are employed in mobile augmented reality(AR) due to the limited computational capacity of mobile terminals, which often leads to unsteadiness of the camera tracking. In this paper, we propose a novel approach to real-time camera tracking in mobile AR using hybrid features to alleviate this problem. By integrating feature points and lines as scene features, hybrid features are generated through the process of point/line features extraction, optimization and fusion, and are used in the real-time estimation of camera parameters. A method for image feature optimization is proposed based on the scene structural analysis to meet the computational constraints of mobile terminals. In order to improve the stability of camera tracking, an iterative screening method is proposed to choose a set of stable feature lines, and hybrid features are adaptively constructed based on the composition and geometry of scene features. It is shown from the experimental results that the proposed method produces more stable and smoother camera trajectories in comparison with the method only using feature points, and a good balance is achieved between the stability and the real-time computation of the camera tracking on a mobile platform.

关键词： mobile augmented reality feature extraction camera tracking hybrid feature mobile platform

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Method for multi-attribute group decision-making based on the compromise weights

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journal of Systems Engineering and Electronics 2010年第4期21卷 591-597页

作者： Shengbao Yao wan'an Cui School of Business Administration Zhongnan University of Economics and Law Wuhan 430073 P. R. China College of Management Guangxi University for Nationalities Nanning 530006 P. R. China

Multi-attribute group decision-making problems are considered where information on both attribute weights and value scores of consequences is *** group decision analysis,if preference information about alternatives is provided by participants,it should be verified whether there exist compromise weights that can support all the preference *** different compromise weight vectors may differ for the ranking of the *** the case that compromise weights exist,the method is proposed to find out all the compromise weight vectors in order to rank the *** on the new feasible domain of attribute weights determined by all the compromise weight vectors and the incomplete information on value scores of consequences,dominance relations between alternatives are checked by a nonlinear goal programming model which can be transformed into a linear one by adopting a *** checked dominance relations uniformly hold for all compromise weight vectors and the incomplete information on value scores of consequences.A final ranking of the alternatives can be obtained by aggregating these dominance relations.

关键词： group decision-making incomplete information preference relation compromise weight.

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Effect of stress ratio on HCf and VHCf properties at temperatures of 20 °C and 700 °C for nickel-based wrought superalloy GH3617M

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Chinese journal of Aeronautics 2019年第9期32卷 2199-2210页

作者： Aoshuang wan junjiang XIONG School of Transportation Science and Engineering Beihang University

This paper attempts to investigate the effects of stress ratio and high temperature on the HCf(high-cycle-fatigue) and VHCf(very-high-cycle-fatigue) behaviors of nickel-based wrought superalloy GH3617 M. fatigue tests over the full HCf and VHCf regimes were conducted on superalloy GH3617 M subjected to constant-amplitude loading at five stress ratios of -1, -0.5, 0,0.4, and 0.8 in environments of 20 °C and 700 °C temperatures. from experimental observation and fractographic analysis, fatigue mechanisms were deduced to reveal the synergistic interaction between high temperature and stress ratio on the HCf and VHCf behaviors of superalloy GH3617 M. A phenomenological model was crafted from available fatigue design knowledge to evaluate the synergistic interaction, and a good correlation between predictions and experiments has been achieved.

关键词： High cycle fatigue High-temperature Nickel-based superalloy Stress ratio Very high cycle fatigue

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基于多分支增强和融合注意力机制的水下图像增强算法

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陕西科技大学学报 2025年第1期43卷 193-202页

作者：姚斌韩典芝徐轩李婉陕西科技大学电子信息与人工智能学院陕西西安710021

由于水对光的折射和吸收,水下图像通常会出现严重的退化,如色偏、模糊、能见度低等.为了提高水下图像的可视性,提出了一种基于多分支增强和融合注意力机制的水下图像增强网络MBfA-GAN.首先,通过分析水下图像的色彩退化和模糊因素,设计... 详细信息

由于水对光的折射和吸收,水下图像通常会出现严重的退化,如色偏、模糊、能见度低等.为了提高水下图像的可视性,提出了一种基于多分支增强和融合注意力机制的水下图像增强网络MBfA-GAN.首先,通过分析水下图像的色彩退化和模糊因素,设计了青品色温修复模块和模糊恢复模块对水下图像进行色彩矫正和模糊恢复.然后,基于对多个分支特征的互补性考虑,采用循环合并策略将多个分支增强的特征利用自适应融合模块进行融合,逐步增强图像细节.最后,设计了融合注意力模块,用于深度挖掘图像在通道维度和像素维度的相关性矩阵,以提高增强图像的真实性.实验结果表明,与现有算法相比,提出的水下图像增强算法去模糊效果较好且颜色更真实,可以有效改善水下图像色偏和模糊的问题.

关键词：水下图像增强多分支增强融合注意力生成对抗网络

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ORDER SCHEDULING WITH CONTROLLABLE PROCESSING TIMES, COMMON DUE DATE AND THE PROCESSING DEADLINE

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journal of Systems Science and Systems Engineering 2017年第2期26卷 199-218页

作者： Qing Yue Guohua wan Antai College of Economics and Management Shanghai Jiao Tong University Shanghai 200030 China

Due date quotation and scheduling are important tools to match demand with production capacity in the MTO （make-to-order） environment. We consider an order scheduling problem faced by a manufacturing f＇trm operating in an MTO environment, where the firm needs to quote a common due date for the customers, and simultaneously control the processing times of customer orders （by allocating extra resources to process the orders） so as to complete the orders before a given deadline. The objective is to minimize the total costs of earliness, tardiness, due date assignment and extra resource consumption. We show the problem is NP-hard, even if the cost weights for controlling the order processing times are identical. We identify several polynomially solvable cases of the problem, and develop a branch and bound algorithm and three Tabu search algorithms to solve the general problem. We then conduct computational experiments to evaluate the performance of the three Tabu-search algorithms and show that they are generally effective in terms of solution quality.

关键词： Order scheduling due date assignment controllable processing times deadline

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IN SITU OBSERVATION Of GROWTH BEHAVIOR AND MORPHOLOGY Of DELTA-fERRITE AS fUNCTION Of SOLIDIfICATION RATE IN AN AISI304 STAINLESS STEEL

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Acta Metallurgica Sinica(English Letters) 2006年第6期19卷 441-448页

作者： G.f.Liang C.Q.wan j.C.Wu G.M.Zhu Y.Yu Y.fang Advanced Technology Institute Technology Center of BaosteelShanghai 201900China Department of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200030China

It was presented the in situ observation of growth behavior and morphology of delta-ferrite as a function of solidification rate in an AISI304 stainless steel. The specimens have been solidified and observed using confocal scanning laser microscopy (CSLM). The δ-phase always appears like cells on the sample surface when critical supercooling occurs, during which the L→δ transformation starts. The solid-liquid (S-L) interface is found to be finger shaped and has no faceted shape. γ phase appears among δ grains due to partitioning of Ni into the melt during solidification, when solidification rate is higher. The mergence of observed δ cells is possible for the steel sample cooled at 7.5℃/min. The formation of dendrites can be observed on the free surface of the steel sample cooled at 150℃/min. The size of solidified delta grains decreases from 120 to 20-80μm, and the volume fraction of solidified austenite increases with increase in solidification rate from 7.5 to 150℃/min. The relation between the tip radius of δ cell and its growth rate is deduced, and the results agree with the experimental values.

关键词： stainless steel confocal scanning laser microscopy δ-ferrite in situ observation solidification

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High-throughput computational screening of oxide double perovskites for optoelectronic and photocatalysis applications

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journal of Energy Chemistry 2021年第6期30卷 351-358,I0009页

作者： Xiaowei jiang wan-jian Yin College of Energy Soochow Institute for Energy and Materials InnovationS(SIEMIS)Soochow UniversitySuzhou 215006JiangsuChina Key Laboratory of Advanced Carbon Materials and Wearable Energy Technologies of jiangsu Province Soochow UniversitySuzhou 215006JiangsuChina Key Lab of Advanced Optical Manufacturing Technologies of jiangsu Province&Key Lab of Modern Optical Technologies of Education Ministry of China Soochow UniversitySuzhou 215006JiangsuChina

Oxide double perovskites A2 B’B"O6 are a class of emerging materials in the fields of optoelectronics and *** to the chemical flexibilities of perovskite structures,there are multiple elemental combinations of cations A,B’,and B",which leading to tremendous *** this study,we comprehensively screened stable oxide double perovskite A2 B’B"O6 from a pool of 2,018 perovskite candidates using a high-throughput computational *** considering a tolerance factor(t)-octahedral factor(μ) phase diagram,138 candidates with fm 3 m, P21/c,and R3 c phases were selected and systematically studied via first-principles calculations based on density functional *** screening procedure finally predicted the existence of 21 stable perovskites,and 14 among them have never been *** with existing experimental results demonstrates that the prediction accuracy for perovskite formability is approximately 90%.The predicted oxide double perovskites exhibit quasi-direct bandgaps ranging from 0 to 4.4 eV with a significantly small direct-indirect bandgap difference,balanced electron and hole effective masses,and strong optical *** newly predicted oxide double perovskites may enlarge the pool of material candidates for applications in optoelectronics and *** study provides a route for computational screening of novel perovskites for functional applications.

关键词： Oxide double perovskites first-principles calculations High-throughput Optoelectronics Photocatalysis

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Effect of alloying on the carrier dynamics in high-performance perovskite solar cells

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journal of Energy Chemistry 2022年第5期31卷 267-274页

作者： jing wang wan-jian Yin College of Energy Soochow Institute for Energy and Materials InnovationS(SIEMIS)Soochow UniversitySuzhou 215006JiangsuChina jiangsu Provincial Key Laboratory for Advanced Carbon Materials and Wearable Energy Technologies Soochow UniversitySuzhou 215006JiangsuChina Light Industry Institute of Electrochemical Power Sources Soochow UniversitySuzhou 215006JiangsuChina

High-efficiency solar cells often require light absorbers prepared from alloys, such as Cd Te_(1-x)Se_(x),CuIn_(x)Ga_(1-x)Se_(2), Cu_(2)ZnSnS_(4-x)Se_(x), and(Cs_(x)fA_(1-x))Pb(I_(1-y)Br_(y))_(3). However, how alloying affects solar cell performance is poorly understood, and determining common features associated with alloying is of significant interest. Herein, we studied the correlation between the A/X site compositional ratio and the photogenerated carrier dynamics using mixed halide perovskites(Cs_(x)fA_(1-x))Pb(I_(1-y)Br_(y))_(3)as *** molecular dynamics calculations demonstrated that charge carrier recombination is highly sensitive to the compositional ratio at the A/X-site. The enhanced lifetime is attributable to the suppression of atomic fluctuations, the weakening of electron-phonon coupling, and a reduction in the electrontransition probability between band edges. The optimal Br concentration was determined to be ~18%, in agreement with experimental observations. This study not only advances our understanding of why mixed perovskites usually exhibit superior experimental photoelectric properties, but also provides a route for optimizing the carrier lifetimes and efficiencies of perovskite solar cells.

关键词： Alloy Nonradiative recombination Mixed-element perovskites Perovskite solar cell

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Investigation on the influence of the initial RDX crystal size on the performance of shaped charge warheads

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Defence Technology（防务技术） 2019年第5期15卷 802-807页

作者： f.Majiet f.j.Mostert Rheinmetall Denel Munition Somerset WestSouth Africa Centre for Scientific&Industrial Research PretoriaSouth Africa

Copper lined wave shaped shaped charges of particular design and liner metallurgy were used to investigate the effect of explosive crystal size on the resultant shaped charge jet *** A3 with RDX of three different average crystal sizes,i.e.30μm,100μm and 300μm were used in the *** other parameters in the charge were kept constant and in particular,care was given to obtain consistent dimensional quality and liner microstructure,in order to prohibit the variation of other *** flash-X-ray diagnostics were used in field tests to obtain the jet parameters from multiple firings of similar *** is found that the varying crystal size of the RDX has a marginal influence in the total jet length of the ***,it is also found that there is less variation between firings in the jet parameters for jets from the charges loaded with the crystal size of 100 μm.

关键词： shaped size crystal

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