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基于海事规则和船舶操纵性的运动规划方法研究

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武汉理工大学学报（交通科学与工程版） 2024年第1期48卷 79-85页

作者：杜希森徐海祥冯辉汪咏武汉理工大学船海与能源动力工程学院武汉430063 武汉理工大学高性能舰船技术教育部重点实验室武汉430063

文中提出了一种基于海事规则和船舶操纵性的运动规划方法.根据海事规则的要求,限制船舶转艏可行域.根据船舶推进器布局分析船舶操纵性能,并通过人工势场求取船舶转艏方向,采用计算势能的方式取代传统方法中计算合力的方式,计算船舶所需... 详细信息

文中提出了一种基于海事规则和船舶操纵性的运动规划方法.根据海事规则的要求,限制船舶转艏可行域.根据船舶推进器布局分析船舶操纵性能,并通过人工势场求取船舶转艏方向,采用计算势能的方式取代传统方法中计算合力的方式,计算船舶所需推力和转矩.将所求推力和转矩作用于船舶,得到一条包含速度和艏向信息的船舶运动轨迹.将并提出的方法与传统人工势场法进行仿真对比.结果表明:所提出的运动规划方法所规划的轨迹能够满足海事规则的要求,与传统人工势场法所规划的轨迹相比更加平滑,且满足船舶操纵性的要求,控制效果更好.

关键词：运动规划海事规则船舶操纵性人工势场法海上避碰

A FAST STOCHASTIC GALERKIN METHOD FOR A CONSTRAINED OPTIMAL CONTROL PROBLEM GOVERNED BY A RANDOM FRACTIONAL DIFFUSION EQUATION

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Journal of Computational Mathematics 2018年第2期36卷 259-275页

作者： Ning du Wanfang Shen School of Mathematics Shandong Univeristy Jinan Shandong 250100 China School of Mathematic and Quantitative Economics Shandong University of Finance and Economics Jinan Shandong 250100 China

We develop a fast stochastic Galerkin method for an optimal control problem governed by a random space-fractional diffusion equation with deterministic constrained control. Optimal control problems governed by a fractional diffusion equation tends to provide a better description for transport or conduction processes in heterogeneous media. Howev- er, the fractional control problem introduces significant computation complexity due to the nonlocal nature of fractional differential operators, and this is further worsen by the large number of random space dimensions to discretize the probability space. We ap- proximate the optimality system by a gradient algorithm combined with the stochastic Galerkin method through the discretization with respect to both the spatial space and the probability space. The resulting linear system can be decoupled for the random and spatial variable, and thus solved separately. A fast preconditioned Bi-Conjugate Gradient Stabilized method is developed to efficiently solve the decoupled systems derived from the fractional diffusion operators in the spatial space. Numerical experiments show the utility of the method.

关键词： Constrained optimal control Fractional diffusion Stochastic Galerkin method,Fast Fourier transform Preconditioned Bi-Conjugate Gradient Stabilized method.

基于特征样件在机测量的机床偏摆误差辨识及其不确定度评估

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制造技术与机床 2024年第7期 164-169页

作者：唐越吕军冯晓冰杜正春上海交通大学机械与动力工程学院上海200240 通用技术集团机床工程研究院有限公司大连分公司辽宁大连116620

机床几何误差的测量和补偿可以提高机床的加工精度。随着机床在机测量技术的发展,在机测量特征样件辨识几何误差逐渐应用到机床的精度检查中。文章提出了一种基于特征样件在机测量的机床偏摆误差辨识方法,应用激光干涉跟踪仪验证了辨识... 详细信息

机床几何误差的测量和补偿可以提高机床的加工精度。随着机床在机测量技术的发展,在机测量特征样件辨识几何误差逐渐应用到机床的精度检查中。文章提出了一种基于特征样件在机测量的机床偏摆误差辨识方法,应用激光干涉跟踪仪验证了辨识方法的正确性,分析了安装误差对于偏摆误差辨识的影响。应用自适应蒙特卡洛法结合误差椭圆评估了在机测量特征样件辨识偏摆误差的不确定度,且应用GUM法验证了不确定度评估方法。特征样件在机测量偏摆误差的方法能够获得可接受的几何误差辨识精度,可作为传统的基于激光干涉测量技术的几何误差辨识的替代方法,非常适合机床精度的周期性检查,来保持机床加工质量的一致性。

关键词：在机测量特征样件机床偏摆误差误差辨识不确定度

Inputs and outputs of insulin receptor

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Protein & Cell 2014年第3期5卷 203-213页

作者： Yipeng du Taotao Wei National Laboratory of Biomacromolecules Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China

The insulin receptor （IR） is an important hub in insulin signaling and its activation is tightly regulated. Upon insulin stimulation, IR is activated through autophos- phorylation, and consequently phosphorylates several insulin receptor substrate （IRS） proteins, including IRS1- 6, Shc and Gab1. Certain adipokines have also been found to activate IR. On the contrary, PTP, Grb and SOCS proteins, which are responsible for the negative regu- lation of IR, are characterized as IR inhibitors. Addi- tionally, many other proteins have been identified as IR substrates and participate in the insulin signaling path- way. To provide a more comprehensive understanding of the signals mediated through IR, we reviewed the upstream and downstream signal molecules of IR, summarized the positive and negative modulators of IR, and discussed the IR substrates and interacting adaptor proteins. We propose that the molecular events associ- ated with IR should be integrated to obtain a better understanding of the insulin signaling pathway and diabetes.

关键词： insulin insulin receptor signaling

Existence of saddle solutions of a nonlinear elliptic equation involving p-Laplacian in more even-dimensional spaces

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Frontiers of Mathematics in China 2016年第6期11卷 1613-1623页

作者： Huahui YAN Zhuoran du College of Mathematics and Econometrics Hunan University Changsha 410082 China

We show that there exist saddle solutions of the nonlinear elliptic equation involving the p-Laplacian, p 〉 2, -△p^u -= f（u） in R^2m for all dimensions satisfying 2m ≥ p, by using sub-supersolution method. The ex... 详细信息

关键词： p-Laplacian saddle solutions sub-supersolution method

A Nonlocal Stokes Systemwith Volume Constraints

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Numerical Mathematics(Theory,Methods and Applications) 2022年第4期15卷 903-937页

作者： Qiang du Zuoqiang Shi Department of Applied Physics and Applied Mathematics and Data Science InstituteColumbia UniversityNew YorkNY 10027USA Yau Mathematical Sciences Center Tsinghua UniversityBeijing 100084China Yanqi Lake Beijing Institute of Mathematical Sciences and Applications Beijing 101408China

In this paper,we introduce a nonlocal model for linear steady Stokes system with physical no-slip boundary *** use the idea of volume constraint to enforce the no-slip boundary condition and prove that the nonlocal model is *** also show that and the solution of the nonlocal system converges to the solution of the original Stokes system as the nonlocality vanishes.

关键词： Nonlocal Stokes system nonlocal operators smoothed particle hydrodynamics incompressible flows well-posedness local limit

ON RESIduAL-BASED A POSTERIORI ERROR ESTIMATORS FOR LOWEST-ORDER RAVIART-THOMAS ELEMENT APPROXIMATION TO CONVECTION-DIFFUSION-REACTION EQUATIONS

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Journal of Computational Mathematics 2014年第5期32卷 522-546页

作者： Shaohong du Xiaoping Xie School of Science Chongqing Jiaotong University Chongqing 400047 China Beijing Computational Science Research Center Beijing 100084 China School of Mathematics Sichuan University Chengdu 610063 China

A new technique of residual-type a posteriori error analysis is developed for the lowest- order Raviart-Thomas mixed finite element discretizations of convection-diffusion-reaction equations in two- or three-dimension. Both centered mixed scheme and upwind-weighted mixed scheme are considered. The a posteriori error estimators, derived for the stress variable error plus scalar displacement error in L_2-norm, can be directly computed with the solutions of the mixed schemes without any additional cost, and are proven to be reliable. Local efficiency dependent on local variations in coefficients is obtained without any saturation assumption, and holds from the cases where convection or reaction is not present to convection- or reaction-dominated problems. The main tools of the analysis are the postprocessed approximation of scalar displacement, abstract error estimates, and the property of modified Oswald interpolation. Numerical experiments are carried out to support our theoretical results and to show the competitive behavior of the proposed posteriori error estimates.

关键词： Convection-diffusion-reaction equation Centered mixed scheme Upwind-weightedmixed scheme Postproeessed approximation A posteriori error estimators.

基于HPLC指纹图谱及化学计量学对温性经筋通贴膏的质量评价

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中华中医药杂志 2024年第8期39卷 4040-4046页

作者：吴颖李亚欣苏安宇杜锦顔冯祥和杜骏吴雪茹黄伟斌王利胜广州中医药大学中药学院广州510006 广州中医药大学第三附属医院广州510006

目的:建立温性经筋通贴膏HPLC指纹图谱及其7种成分含量测定方法,并结合化学计量学的方法对其进行分析,为其质量评价提供科学依据。方法:采用HPLC法,测定12批温性经筋通贴膏指纹图谱,确定共有峰并进行相似度评价;通过对照品确定盐酸小檗... 详细信息

目的:建立温性经筋通贴膏HPLC指纹图谱及其7种成分含量测定方法,并结合化学计量学的方法对其进行分析,为其质量评价提供科学依据。方法:采用HPLC法,测定12批温性经筋通贴膏指纹图谱,确定共有峰并进行相似度评价;通过对照品确定盐酸小檗碱、补骨脂素、异补骨脂素、丹皮酚、毛蕊异黄酮苷、芒柄花素和大黄素成分,并进行含量测定;借助SPSS 16.0、SIMCA-P 14.1等软件对12批温性经筋通贴膏进行聚类分析、主成分分析、最小二乘判别分析(OPLS-DA)等化学计量学分析。结果:12批温性经筋通贴膏指纹图谱共确定了32个共有峰,相似度均>0.9,并指认了7个成分峰,7种成分的线性关系均比较良好(R2≥0.9990),重复性、精密度、稳定性考察中的RSD均<5%,回收率试验按照已知含量的100%分别加入各对照品,回收率RSD均<5%;12批次温性经筋通贴膏7种成分含量范围分别在17.69~52.48,24.07~50.86,22.73~58.39,74.76~130.30,7.71~10.25,1.07~5.10,16.18~46.89μg/g;化学计量学方法分析显示可将S5划分为Ⅰ类,其他批次为Ⅱ类,OPLS-DA共确定15个差异标志物。结论:本研究建立的指纹图谱和含量测定方法科学、可靠,并结合了化学计量学,为温性经筋通贴膏质量控制及后期剂型研究奠定了基础。

关键词：温性经筋通贴膏指纹图谱含量测定质量化学计量学

KRAS mutation testing in metastatic colorectal cancer

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World Journal of Gastroenterology 2012年第37期18卷 5171-5180页

作者： Cong Tan Xiang du Department of Oncology Shanghai Med-ical SchoolFudan UniversityShanghai 200032China Department of Pathology Shanghai Can-cer CenterFudan UniversityShanghai 200032China

The KRAS oncogene is mutated in approximately 35%-45% of colorectal cancers, and KRAS mutational status testing has been highlighted in recent years. The most frequent mutations in this gene, point substitutions in codons 12 and 13, were validated as negative predictors of response to anti-epidermal growth factor receptor antibodies. Therefore, determining the KRAS mutational status of tumor samples has become an essential tool for managing patients with colorectal cancers. Currently, a variety of detection methods have been established to analyze the mutation status in the key regions of the KRAS gene; however, several challenges remain related to standardized and uniform testing, including the selection of tumor samples, tumor sample processing and optimal testing methods. Moreover, new testing strategies, in combination with the mutation analysis of BRAF , PIK3CA and loss of PTEN proposed by many researchers and pathologists, should be promoted. In addition, we recommend that microsatellite instability, a prognostic factor, be added to the abovementioned concomitant analysis. This review provides an overview of KRAS biology and the recent advances in KRAS mutation testing. This review also addresses other aspects of status testing for determining the appropriate treatment and offers insight into the potential drawbacks of mutational testing.

关键词： KRAS Epidermal growth factor receptor Metastatic colorectal cancer Testing status Biomarker