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A Newton multigrid method for steady-state shallow water equations with topography and dry areas

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Applied Mathematics and Mechanics(English Edition) 2016年第11期37卷 1441-1466页

作者： kailiang wu Huazhong TANG LMAM School of Mathematical Sciences Peking University HEDPS CAPT & LMAM School of Mathematical SciencesPeking University School of Mathematics and Computational Science Xiangtan University

A Newton multigrid method is developed for one-dimensional （1D） and two- dimensional （2D） steady-state shallow water equations （SWEs） with topography and dry areas. The nonlinear system arising from the well-balanced finite volume discretization of the steady-state SWEs is solved by the Newton method as the outer iteration and a geometric multigrid method with the block symmetric Gauss-Seidel smoother as the inner iteration. The proposed Newton multigrid method makes use of the local residual to regularize the Jacobian matrix of the Newton iteration, and can handle the steady- state problem with wet/dry transition. Several numerical experiments are conducted to demonstrate the efficiency, robustness, and well-balanced property of the proposed method. The relation between the convergence behavior of the Newton multigrid method and the distribution of the eigenvalues of the iteration matrix is detailedly discussed.

关键词： Newton method multigrid block symmetric Gauss-Seidel shallow waterequation (SWE) steady-state solution

Sequential Approximation of Functions in Sobolev Spaces Using Random Samples

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Communications on Applied Mathematics and Computation 2019年第3期1卷 449-466页

作者： kailiang wu Dongbin Xiu Department of Mathematics The Ohio State UniversityColumbusOH 43210USA

We present an iterative algorithm for approximating an unknown function sequentially using random samples of the function values and gradients. This is an extension of the recently developed sequential approximation (SA) method, which approximates a target function using samples of function values only. The current paper extends the development of the SA methods to the Sobolev space and allows the use of gradient information naturally. The algorithm is easy to implement, as it requires only vector operations and does not involve any matrices. We present tight error bound of the algorithm, and derive an optimal sampling probability measure that results in fastest error convergence. Numerical examples are provided to verify the theoretical error analysis and the effectiveness of the proposed SA algorithm.

关键词： Approximation theory Sequential approximation Randomized algorithm Sobolev space Optimal sampling probability measure

A Non-intrusive Correction Algorithm for Classification Problems with Corrupted Data

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Communications on Applied Mathematics and Computation 2021年第2期3卷 337-356页

作者： Jun Hou Tong Qin kailiang wu Dongbin Xiu Department of Mathematics The Ohio State UniversityColumbusOH 43210USA

A novel correction algorithm is proposed for multi-class classification problems with corrupted training *** algorithm is non-intrusive,in the sense that it post-processes a trained classification model by adding a correction procedure to the model *** correction procedure can be coupled with any approximators,such as logistic regression,neural networks of various architectures,*** the training dataset is sufficiently large,we theoretically prove(in the limiting case)and numerically show that the corrected models deliver correct classification results as if there is no corruption in the training *** datasets of finite size,the corrected models produce significantly better recovery results,compared to the models without the correction *** of the theoretical findings in the paper are verified by our numerical examples.

关键词： Data corruption Deep neural network Cross-entropy Label corruption Robust loss

Advanced rare earth tantalate RETaO_(4)(RE=Dy,Gd and Sm) with excellent oxygen/thermal barrier performance

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Journal of Rare Earths 2024年第8期42卷 1595-1603,I0007页

作者： Jun Wang Jianyu Li Chunyu Jiang Jianbo Song Xing Yang Xiaolong Ma kailiang Luo Peng wu Xiaoyu Chong Jing Feng Faculty of Material Science and Engineering Kunming University of Science and TechnologyKunming650093China Shanxi Tianxuan Coating Technology Co. LtdXi'an710000China

Thermal barrier coatings(TBCs) materials with lowered the rmal and oxygen ion conductivity can provide thermal and oxidative protection for high te mperature hot-end components in aero nautical engines and gas turbines,The rare-earth tantalate RETaO_(4)(RE=Dy,Gd and Sm) ceramics with monoclinic(m) phase were successfully synthesized via spark plasma *** vacancies responsible for the thermal and oxygen ion conductivities of RETaO_(4) were demonstrated by atomic-resolution energy dispersive Xray and X-ray photoelectron *** the three samples,DyTaO_(4) has excellent oxygen/thermal barrier *** to the current service thermal barrier coating material ZrO_(2)-8 wt% Y_(2)O_(3)(8 YSZ),DyTaO_(4) has an ultra-low oxygen ion conductivity benefiting from low oxygen vacancy concentration and strong stretching force *** intrinsic thermal conductivity of DyTaO_(4)is 68.2% less than that of 8 ***,the thermal expansion rate curves indicate that the phase transformation does not happen from room te mperature to 1200℃.The above results demonstrate that high-growth rate the rmally grown oxide can be retarded by creating dense DyTaO_(4) coating with lowered thermal and oxygen ion conductivity.

关键词： Thermal barrier coatings Rare earths Oxygen vacancies Thermal conductivity Oxygen ion conductivity

脂肪酸合成酶在乳腺浸润性微乳头状癌中的表达及作用研究

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中国肿瘤临床 2022年第18期49卷 919-925页

作者：张婧越吴开良吕鉴可付丽天津医科大学肿瘤医院乳腺病理科国家恶性肿瘤临床医学研究中心天津市肿瘤防治重点实验室天津市恶性肿瘤临床医学研究中心乳腺癌防治教育部重点实验室天津市300060

目的:探讨脂肪酸合成酶(fatty acid synthase,FASN)表达与乳腺浸润性微乳头状癌(invasive micropapillary carcinoma,IMPC)临床病理学特征及预后的相关性。方法:选取2010年1月至2015年12月天津医科大学肿瘤医院105例乳腺IMPC组及105例... 详细信息

目的:探讨脂肪酸合成酶(fatty acid synthase,FASN)表达与乳腺浸润性微乳头状癌(invasive micropapillary carcinoma,IMPC)临床病理学特征及预后的相关性。方法:选取2010年1月至2015年12月天津医科大学肿瘤医院105例乳腺IMPC组及105例乳腺浸润性导管癌-非特殊类型(invasive ductal carcinoma-no special type,IDC-NOS)组的病例,行FASN免疫组织化学法染色后进行统计学分析。利用CCK8、划痕实验检测FASN对T47D乳腺癌细胞增殖、迁移能力的影响。利用蛋白免疫印迹实验检测FASN对Wnt/β-catenin信号通路及上皮间质转化(epithelial-mesenchymal transition,EMT)的影响。结果:FASN在IMPC中的表达为61.0%(64/105),显著高于IDC-NOS的31.4%(33/105),两者比较差异具有统计学意义(P<0.001)。IM-PC中的FASN表达与患者脉管癌栓、N分期、Ki-67表达呈正相关(P<0.05),与IMPC患者的无病生存(disease-free survival,DFS)期和总生存(overall survival,OS)期呈负相关(P<0.01)。FASN高表达是IMPC患者DFS和OS降低的独立危险因素(P<0.05)。敲低FASN后T47D细胞的增殖、迁移能力显著下降(P<0.001)。FASN促进T47D细胞中Wnt/β-catenin通路及EMT。结论:FASN通过Wnt/β-catenin信号通路促进EMT导致乳腺癌细胞增殖、迁移。FASN高表达与IMPC高侵袭、高转移等临床病理学特征呈正相关,是预测IMPC患者预后的独立危险因素。

关键词：脂肪酸合成酶浸润性微乳头状癌乳腺癌预后分析上皮间质转化

sLe^(x) expression in invasive micropapillary breast carcinoma is associated with poor prognosis and can be combined with MUC1/EMA as a supplementary diagnostic indicator

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Cancer Biology & Medicine 2021年第2期18卷 477-489页

作者： Yawen Song Hui Sun kailiang wu Jianke Lyu Jingyue Zhang Feng Gu Yongjie Ma Beibei Shen Chijuan Wang Xiaojiao Chen Jing Xu Weidong Li Fangfang Liu Li Fu Department of Breast Cancer Pathology and Research Laboratory Tianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjinTianjin’s Clinical Research Center for CancerKey Laboratory of Breast Cancer Prevention and TherapyTianjin Medical UniversityMinistry of EducationBreast Cancer Innovation Team of the Ministry of EducationState Key Laboratory of Breast Cancer ResearchTianjin 300060China

Objective: Mucin 1(MUC1/EMA) and sialyl Lewis X(sLe^(x)) indicate polarity reversal in invasive micropapillary carcinoma(IMPC). The purpose of this study was to evaluate the expression of MUC1/EMA and sLe^(x) and to assess their diagnostic and prognostic value in patients with ***: The expression of sLe^(x) and MUC1/EMA in 100 patients with IMPC and a control group of 89 patients with invasive ductal carcinoma not otherwise specified(IDC-NOS) were analyzed with IHC. Fresh tumor tissues were collected from patients with IMPC or IDC-NOS for primary culture and immunofluorescence ***: The rate of nodal metastasis was higher in patients with IMPC than those with IDC-NOS, and IMPC cells tended to express more sLe^(x) and MUC1/EMA in the cytomembranes(the stroma-facing surfaces of the micropapillary clusters) than IDC-NOS cells. In IMPC, high cytomembrane expression of sLe^(x), but not MUC1/EMA, indicated poor prognosis. In addition, among the 100 patients with IMPC, 10 patients had sLe^(x)+/EMA-expression patterns, and 8 patients had sLe^(x)-/EMA+ expression patterns. The primary IMPC cells were suspended, non-adherent tumor cell clusters, whereas the primary IDC cells were adherent tumor cells. Immunofluorescence analysis showed that MUC1/EMA and sLe^(x) were co-expressed on the cytomembranes in IMPC cell clusters and in the cytoplasm in IDC-NOS ***: sLe^(x) can be used as a prognostic indicator and can be combined with MUC1/EMA as a complementary diagnostic indicator to avoid missed IMPC diagnosis.

关键词： Invasive micropapillary carcinoma polarity reversal diagnostic indicator EMA sLe^(x)

Ballistic performances of the hourglass lattice sandwich structures under high-velocity fragments

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Defence Technology（防务技术） 2024年第1期31卷 312-325页

作者： He-xiang wu Jia Qu Lin-zhi wu Key Laboratory of Advanced Ship Materials and Mechanics College of Aerospace and Civil EngineeringHarbin Engineering UniversityHarbin150001China School of Civil Engineering Northeast Forestry UniversityHarbin150040China

In this paper,the numerical simulation method is used to study the ballistic performances of hourglass lattice sandwich structures with the same mass under the vertical incidence of *** is paid to elucidating the influences of rod cross-section dimensions,structure height,structure layer,and rod inclination angle on the deformation mode,ballistic performances,and ability to change the ballistic direction of *** results show that the ballistic performances of hourglass lattice sandwich structures are mainly affected by their structural *** this respect,structural parameters optimization of the hourglass lattice sandwich structures enable one to effectively improve their ballistic limit velocity and,consequently,ballistic performances.

关键词： Hourglass lattice sandwich structures Ballistic performances high-velocity Finite element analysis

Resilience-incorporated seismic risk assessment of precast concrete frames with“dry”connections

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 403-425页

作者： wu Chenhao Tang Yuchuan Cao Xuyang wu Gang Key Laboratory of Concrete and Prestressed Concrete Structures of the Ministry of Education Nanjing 211102China Department of Civil and Environmental Engineering University of CaliforniaLos AngelesCA 90095USA School of Civil Engineering Southeast UniversityNanjing 211102China College of Civil and Transportation Engineering Hohai UniversityNanjing 210024China

A resilience-incorporated risk assessment framework is proposed and demonstrated in this study to manifest the advantageous seismic resilience of precast concrete frame(PCF)structures with“dry”connections in terms of their low damage and rapid *** framework integrates various uncertainties in the seismic hazard,fragility,capacity,demand,loss functions,and post-earthquake *** this study,the PCF structures are distinguished from ordinary reinforced concrete frame(RCF)structures by characterizing multiple limit states for the PCF based on its unique damage ***,probabilistic story-wise pushover analyses are performed to yield story-wise capacities for the predefined limit *** the seismic resilience analysis,a step-wise recovery model is proposed to idealize the functionality recovery process,with separate considerations of the repair and non-repair *** recovery model leverages the economic loss and downtime to delineate the stochastic post-earthquake recovery curves for the resilience loss *** such,contingencies in the probabilistic post-earthquake repairs are incorporated and the empirical judgments on the recovery parameters are largely *** proposed framework is demonstrated through a comparative study between two“dry”connected PCFs and one RCF designed as alternative structural systems for a prototype *** results from the risk quantification indicate that the PCFs show reduced loss hazards and lower expected losses relative to the ***,the PCF equipped with energy dissipation devices at the“dry”connections largely reduces the expected economic loss,downtime,and resilience loss by 29%,56%,and 60%,respectively,compared to the RCF.

关键词： precast concrete frame non-emulative precast system seismic resilience seismic risk functional recovery

New findings on the influence of El Nino events on tropical cyclone formation

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Science China Earth Sciences 2024年第3期67卷 892-893页

作者： Liguang wu Department of Atmospheric and Oceanic Sciences Institute of Atmospheric SciencesFudan UniversityShanghai 200438China

Tropical cyclones typically form over warm tropical and subtropical ocean surfaces, as their formation and intensification rely primarily on the energy provided by the ocean. Pioneering research by Gray (1968) revealed that the formation of tropical cyclones requires the sea surface temperature (SST) to be no less than 26.5℃. Consequently, SST is commonly recognized as a crucial parameter among the environmental factors influencing tropical cyclone formation(Gray, 1979;Emanuel and Nolan, 2004).

关键词： tropical cyclone ocean