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个体化预测盆腔器官脱垂盆底重建手术后压力性尿失禁发生风险的列线图模型构建

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国际泌尿系统杂志 2025年第1期45卷 87-91页

作者：刘燕孙艳周明刘晨浩宣城市中心医院妇产科宣城242000

目的探讨盆腔器官脱垂患者行盆底重建手术后发生压力性尿失禁的危险因素,构建并验证风险预测列线图模型。方法纳入2016年10月至2022年8月期间于本院行盆底重建手术的301例盆腔器官脱垂患者作为研究对象,根据术后是否发生压力性尿失禁将... 详细信息

目的探讨盆腔器官脱垂患者行盆底重建手术后发生压力性尿失禁的危险因素,构建并验证风险预测列线图模型。方法纳入2016年10月至2022年8月期间于本院行盆底重建手术的301例盆腔器官脱垂患者作为研究对象,根据术后是否发生压力性尿失禁将患者分为对照组(未发生压力性尿失禁,228例)和观察组(发生压力性尿失禁,73例)。采用多因素logistic回归分析筛选盆腔器官脱垂患者盆底重建手术后发生压力性尿失禁的影响因素;采用R软件构建盆腔器官脱垂患者盆底重建手术后发生压力性尿失禁的风险预测列线图模型,通过校准曲线验证模型的一致性,通过受试者工作特征(ROC)曲线及曲线下面积评估模型的预测价值及区分度。结果观察组患者的年龄≥50岁、绝经、产次≥3次、有高血压、有糖尿病、有阴道分娩、有会阴裂伤的比例均高于对照组(均P<0.05)。多因素logistic回归分析结果显示:年龄≥50岁、绝经、产次≥3次、有高血压、有糖尿病、有阴道分娩、有会阴裂伤均是盆腔器官脱垂患者盆底重建手术后发生压力性尿失禁的独立危险因素(均P<0.05)。理想曲线与校正曲线的拟合度较好,实际概率与预测概率间存在较好的一致性。ROC曲线的曲线下面积为0.897(95%CI:0.856~0.939),表明该列线图模型的预测价值和区分度良好。结论本研究构建的列线图模型有望成为盆腔器官脱垂患者盆底重建手术后发生压力性尿失禁的重要预测工具。

关键词：尿失禁,压力性盆腔器官脱垂盆底重建术

Fully Nonlinear Time Domain Analysis for Hydrodynamic Performance of An Oscillating Wave Surge Converter

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China Ocean Engineering 2018年第5期32卷 582-592页

作者： sun Shi-yan sun Shi-li WU Guo-xiong School of Naval Architecture & Ocean Engineering Jiangsu University of Science and Technology College of Shipbuilding Engineering Harbin Engineering University Department of Mechanical Engineering University College London

The hydrodynamic behaviour of an oscillating wave surge converter(OWSC) in large motion excited by nonlinear waves is investigated. The mechanism through which the wave energy is absorbed in the nonlinear system is analysed. The mathematical model used is based on the velocity potential theory together with the fully nonlinear boundary conditions on the moving body surface and deforming free surface. The problem is solved by the boundary element method. Numerical results are obtained to show how to adjust the mechanical properties of the OWSC to achieve the best efficiency in a given wave, together with the nonlinear effect of the wave height. Numerical results are also provided to show the behaviour of a given OWSC in waves of different frequencies and different heights.

关键词： wave energy oscillating wave surge converter nonlinear wave/structure interactions boundary element method

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Tsinghua Science and Technology 2017年第2期22卷 174-184页

作者： Peng Li Hong Luo yan sun School of Computer Science Beijing University of Posts and TelecommunicationBeijing 100876China the Beijing Key Lab of Intelligent Telecommunication Software and Multimedia Beijing 100876China

In this paper, we target a similarity search among data supply chains, which plays an essential role in optimizing the supply chain and extending its value. This problem is very challenging for application-oriented data supply chains because the high complexity of the data supply chain makes the computation of similarity extremely complex and inefficient. In this paper, we propose a feature space representation model based on key points,which can extract the key features from the subsequences of the original data supply chain and simplify it into a feature vector form. Then, we formulate the similarity computation of the subsequences based on the multiscale features. Further, we propose an improved hierarchical clustering algorithm for a similarity search over the data supply chains. The main idea is to separate the subsequences into disjoint groups such that each group meets one specific clustering criteria; thus, the cluster containing the query object is the similarity search result. The experimental results show that the proposed approach is both effective and efficient for data supply chain retrieval.

关键词： data supply chain similarity search feature space hierarchical clustering

Weak ENSO Asymmetry Due to Weak Nonlinear Air–Sea Interaction in CMIP5 Climate Models

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Advances in Atmospheric Sciences 2016年第3期33卷 352-364页

作者： yan sun Fan WANG De-Zheng sun Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao 266071 Laboratory for Ocean Dynamics and Climate Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071 Cooperative Institute for Research in Environmental SciencesUniversity of Coloradoand NOAA/Earth System Research Laboratory/Physical Sciences DivisionBoulderColorado 80305USA

State-of-the-art climate models have long-standing intrinsic biases that limit their simulation and projection capabilities. Significantly weak ENSO asymmetry and weakly nonlinear air-sea interaction over the tropical Pacific was found in CMIP5 （Coupled Model Intercomparison Project, Phase 5） climate models compared with observation. The results suggest that a weak nonlinear air-sea interaction may play a role in the weak ENSO asymmetry. Moreover, a weak nonlinearity in air-sea interaction in the models may be associated with the biases in the mean climate--the cold biases in the equatorial central Pacific. The excessive cold tongue bias pushes the deep convection far west to the western Pacific warm pool region and suppresses its development in the central equatorial Pacific. The deep convection has difficulties in further moving to the eastern equatorial Pacific, especially during extreme El Nifio events, which confines the westerly wind anomaly to the western Pacific. This weakens the eastern Pacific El Nifio events, especially the extreme E1 Nifio events, and thus leads to the weakened ENSO asymmetry in climate models. An accurate mean state structure （especially a realistic cold tongue and deep convection） is critical to reproducing ENSO events in climate models. Our evaluation also revealed that ENSO statistics in CMIP5 climate models are slightly improved compared with those of CMIP3. The weak ENSO asymmetry in CMIP5 is closer to the observation. It is more evident in CMIP5 that strong ENSO activities are usually accompanied by strong ENSO asymmetry, and the diversity of ENSO amplitude is reduced.

关键词： ENSO asymmetry nonlinearity air-sea interaction cold tongue CMIP5 deep convection

Dynamic Optimization Method on Electromechanical Coupling System by Exponential Inertia Weight Particle Swarm Algorithm

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Chinese Journal of Mechanical Engineering 2009年第4期22卷 602-607页

作者： LI Qiang WU Jianxin sun yan College of Mechanical and Electrical Engineering North China University of Technology Beijing 100144 China College of Mechanical Engineering lnner Mongolia University of Technology Hohhot 010051 China

Dynamic optimization of electromechanical coupling system is a significant engineering problem in the field of mechatronics. The performance improvement of electromechanical equipment depends on the system design parameters. Aiming at the spindle unit of refitted machine tool for solid rocket, the vibration acceleration of tool is taken as objective function, and the electromechanical system design parameters are appointed as design variables. Dynamic optimization model is set up by adopting Lagrange-Maxwell equations, Park transform and electromechanical system energy equations. In the procedure of seeking high efficient optimization method, exponential function is adopted to be the weight function of particle swarm optimization algorithm. Exponential inertia weight particle swarm algorithm（EPSA）, is formed and applied to solve the dynamic optimization problem of electromechanical system. The probability density function of EPSA is presented and used to perform convergence analysis. After calculation, the optimized design parameters of the spindle unit are obtained in limited time period. The vibration acceleration of the tool has been decreased greatly by the optimized design parameters. The research job in the paper reveals that the problem of dynamic optimization of electromechanical system can be solved by the method of combining system dynamic analysis with reformed swarm particle optimizati on. Such kind of method can be applied in the design of robots, NC machine, and other electromechanical equipments.

关键词： particle swarm algorithm electromechanical coupling system dynamic optimization

A Trust-Based Hierarchical Consensus Mechanism for Consortium Blockchain in Smart Grid

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Tsinghua Science and Technology 2023年第1期28卷 69-81页

作者： Xingguo Jiang Aidong sun yan sun Hong Luo Mohsen Guizani School of Computer Science(National Pilot Software Engineering School) Beijing University of Posts and TelecommunicationsBeijing 100876China Institute of Food safety and Nutrition Jiangsu Academy of Agricultural SciencesNanjing 210000China Computer Science and Engineering Department Qatar UniversityDoha 2713Qatar

As the smart grid develops rapidly,abundant connected devices offer various trading *** raises higher requirements for secure and effective data *** centralized data management does not meet the above ***,smart grid with conventional consortium blockchain can solve the above ***,in the face of a large number of nodes,existing consensus algorithms often perform poorly in terms of efficiency and *** this paper,we propose a trust-based hierarchical consensus mechanism(THCM)to solve this ***,we design a hierarchical mechanism to improve the efficiency and ***,intra-layer nodes use an improved Raft consensus algorithm and inter-layer nodes use the Byzantine Fault Tolerance ***,we propose a trust evaluation method to improve the election process of ***,we implement a prototype system to evaluate the performance of *** results demonstrate that the consensus efficiency is improved by 19.8%,the throughput is improved by 12.34%,and the storage is reduced by 37.9%.

关键词： consortium blockchain consensus algorithm trust evaluation method smart grid Internet of Things(IoT)

Implications from γ-globulin adsorption onto cation exchangers fabricated by sequential alginate grafting and sulfonation

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Chinese Journal of Chemical Engineering 2021年第1期34卷 121-125页

作者： Xianxiu Li yan sun Xiaoyan Dong Department of Biochemical Engineering School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300354China Key Laboratory of Systems Bioengineering and Frontiers Science Center for Synthetic Biology(Ministry of Education) Tianjin UniversityTianjin 300072China

Our previous work proved that high adsorption capacity and uptake rate of lysozyme were achieved on alginate(Alg)-grafted re sin with an ionic capacity(IC) of 240 mmol·L^(-1)(Alg-FF-240).Moreover,the salt-tolerant feature of Alg-FF-230 was improved by using sequential alginate grafting and sulfonation *** by the enhanced adsorption performance of lysozyme,we have herein proposed to investigate the static and dynamic adsorption behaviors of γ-globulin on a series of Alg-grafted resins with different grafting densities and sulfonation *** adsorption ca pacity of γ-globulin decreased with increa sing alginate-grafting density(IC) from 160 to 230 mmol·L^(-1) at 0 mmol·L^(-1) NaCl because of the steric hindrance caused by the alginate-grafting *** of ionic strength(IS) indicated that the adsorption capacities of the resins with the IC value of 230-370 mmol·L^(-1) were much higher than CM Sepharose FF at 50-100 mmol·L^(-1) NaCl,and the uptake rate of Alg-FF-230 was about twice as much as that of CM Sepharose *** work demonstrated the important effects of alginate-grafting layer and IS in γ-globulin adsorption behavior,which would be helpful in the design of Alggrafted resins and the selection of proper IS condition for protein purification.

关键词： Alginate Sulfonation γ-Globulin Adsorption capacity Uptake rate

Dynamic flight stability of hovering insects

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Acta Mechanica Sinica 2007年第3期23卷 231-246页

作者： Mao sun Jikang Wang yan Xiong Institute of Fluid Mechanics Beihang UniversityBeijing 100083 China

The equations of motion of an insect with flapping wings are derived and then simplified to that of a flying body using the ＂rigid body＂ assumption. On the basis of the simplified equations of motion, the longitudinal dynamic flight stability of four insects （hoverfly, cranefly, dronefly and hawkmoth） in hovering flight is studied （the mass of the insects ranging from 11 to 1,648 mg and wingbeat frequency from 26 to 157Hz）. The method of computational fluid dynamics is used to compute the aerodynamic derivatives and the techniques of eigenvalue and eigenvector analysis are used to solve the equations of motion. The validity of the ＂rigid body＂ assumption is tested and how differences in size and wing kinematics influence the applicability of the ＂rigid body＂ assumption is investigated. The primary findings are：（1） For insects considered in the present study and those with relatively high wingbeat frequency （hoverfly, drone fly and bumblebee）, the ＂rigid body＂ assumption is reasonable, and for those with relatively low wingbeat frequency （cranefly and howkmoth）, the applicability of the ＂rigid body＂ assumption is questionable. （2） The same three natural modes of motion as those reported recently for a bumblebee are identified, i.e., one unstable oscillatory mode, one stable fast subsidence mode and one stable slow subsidence mode. （3） Approximate analytical expressions of the eigenvalues, which give physical insight into the genesis of the natural modes of motion, are derived. The expressions identify the speed derivative Mu （pitching moment produced by unit horizontal speed） as the primary source of the unstable oscillatory mode and the stable fast subsidence mode and Zw （vertical force produced by unit vertical speed） as the primary source of the stable slow subsidence mode.

关键词： Insect Dynamic stability Equations of motion Navier-Stokes simulation Natural modes of motion

工会组织参与数字化基层治理的实践策略:以上海为例

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山东工会论坛 2025年第1期31卷 25-36页

作者：孙岩邹卫民唐磊上海工会管理职业学院上海200082

当前基层治理已经进入数字化转型的制度重塑阶段,工会作为群团组织具有先天的组织优势,能够成为基层治理格局建设的重要依靠力量。上海已将“工会”纳入城市数字化转型总体规划,工会与街镇在整合工会资源到城市运行管理系统的过程中,存... 详细信息

当前基层治理已经进入数字化转型的制度重塑阶段,工会作为群团组织具有先天的组织优势,能够成为基层治理格局建设的重要依靠力量。上海已将“工会”纳入城市数字化转型总体规划,工会与街镇在整合工会资源到城市运行管理系统的过程中,存在着底层逻辑不同、系统协同性差、应用场景不足、数据研判价值低等问题,亟须从数据共享平台建设、数据映射社会运行能力、开发适合工会配套插件、精准辅助决策研判等方面获得技术赋能。

关键词：工会基层治理数字化转型实践策略