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基于WSS-Pointnet的变电站点云弱监督语义分割方法
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作者 裴少通 孙海超 +2 位作者 胡晨龙 王玮琦 兰博 《电工技术学报》 北大核心 2026年第1期234-245,共12页
现有的变电站点云语义分割算法均采用完全监督学习,需要大量人工标注点云数据,导致分割任务耗时长且成本高昂。为解决这一问题,该文提出一种基于PointNet改进的弱监督语义分割PointNet(WSS-PointNet)算法。首先,通过构建多层降采样结构... 现有的变电站点云语义分割算法均采用完全监督学习,需要大量人工标注点云数据,导致分割任务耗时长且成本高昂。为解决这一问题,该文提出一种基于PointNet改进的弱监督语义分割PointNet(WSS-PointNet)算法。首先,通过构建多层降采样结构,结合采样层与分组层对输入点云数据进行多尺度特征提取,从而捕捉点云在不同尺度上的几何和拓扑信息。在此基础上,引入PointNet结构以进一步提取区域特征,优化局部特征整合与全局特征表示;针对粗粒度语义特征的优化,提出膨胀式语义信息嵌入与浸染式语义信息嵌入两种模块,分别采用“由内而外”和“由外而内”的信息传递策略对点云语义信息进行细致处理,两种嵌入机制均基于图卷积神经网络,通过捕捉局部连接模式与信息共享实现语义特征的高效传播。其次,构建变电站点云数据集,并对WSS-PointNet算法进行消融实验,同时与主流的完全监督学习算法和弱监督学习算法进行对比。经实验验证,WSS-PointNet相比于改进前将变电站点云分割的总体精度(OA)提高了10.3个百分点,平均交并比(mIoU)提高了10.1个百分点,平均准确率(mAcc)提高了10.5个百分点,同时在标注所需时间方面缩短了90%,接近完全监督算法中最好的分割效果。该模型可显著降低处理变电站点云数据的时间与成本,同时保持点云分割的高精度。 展开更多
关键词 点云语义分割 弱监督方法 膨胀式语义信息嵌入 浸染式语义信息嵌入 变电站
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On the Base Point Locus of Surface Parametrizations:Formulas and Consequences
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作者 David A.Cox Sonia Pérez-Díaz J.Rafael Sendra 《Communications in Mathematics and Statistics》 SCIE 2022年第4期757-783,共27页
This paper shows that the multiplicity of the base point locus of a projective rational surface parametrization can be expressed as the degree of the content of a univariate resultant.As a consequence,we get a new pro... This paper shows that the multiplicity of the base point locus of a projective rational surface parametrization can be expressed as the degree of the content of a univariate resultant.As a consequence,we get a new proof of the degree formula relating the degree of the surface,the degree of the parametrization,the base point multiplicity and the degree of the rational map induced by the parametrization.In addition,we extend both formulas to the case of dominant rational maps of the projective plane and describe how the base point loci of a parametrization and its reparametrizations are related.As an application of these results,we explore how the degree of a surface reparametrization is affected by the presence of base points. 展开更多
关键词 base point Hilbert-Samuel multiplicity Surface parametrization Reparametrization Parametrization degree Surface degree
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A Correntropy-based Affine Iterative Closest Point Algorithm for Robust Point Set Registration 被引量:7
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作者 Hongchen Chen Xie Zhang +2 位作者 Shaoyi Du Zongze Wu Nanning Zheng 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第4期981-991,共11页
The iterative closest point(ICP)algorithm has the advantages of high accuracy and fast speed for point set registration,but it performs poorly when the point set has a large number of noisy outliers.To solve this prob... The iterative closest point(ICP)algorithm has the advantages of high accuracy and fast speed for point set registration,but it performs poorly when the point set has a large number of noisy outliers.To solve this problem,we propose a new affine registration algorithm based on correntropy which works well in the affine registration of point sets with outliers.Firstly,we substitute the traditional measure of least squares with a maximum correntropy criterion to build a new registration model,which can avoid the influence of outliers.To maximize the objective function,we then propose a robust affine ICP algorithm.At each iteration of this new algorithm,we set up the index mapping of two point sets according to the known transformation,and then compute the closed-form solution of the new transformation according to the known index mapping.Similar to the traditional ICP algorithm,our algorithm converges to a local maximum monotonously for any given initial value.Finally,the robustness and high efficiency of affine ICP algorithm based on correntropy are demonstrated by 2D and 3D point set registration experiments. 展开更多
关键词 AFFINE ITERATIVE closest point(ICP)algorithm correntropy-based ROBUST point set REGISTRATION
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Spaces with σ-point-discrete N_0-weak bases 被引量:1
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作者 SHEN Rong-xin LIN Shou 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2013年第1期116-126,共11页
It is discussed in this paper the spaces with σ-point-discrete N_0-weak bases. The main results are: (1) A space X has a σ-compact-finite N_0-weak base if and only if X is a k-space with a σ-point-discrete N_0-w... It is discussed in this paper the spaces with σ-point-discrete N_0-weak bases. The main results are: (1) A space X has a σ-compact-finite N_0-weak base if and only if X is a k-space with a σ-point-discrete N_0-weak base; (2) Under (CH), every separable space with a σ-point-discrete N_0-weak base has a countable N_0-weak base. 展开更多
关键词 N_0-weak base σ-point-discrete network σ-compact-finite network separable space.
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Global point tracking based panoramic image stabilization system 被引量:1
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作者 朱娟娟 郭宝龙 吴宪祥 《Optoelectronics Letters》 EI 2009年第1期61-63,共3页
A novel image stabilization system is presented,which consists of a global feature point tracking based motion estimation,a Kalman filtering based motion smoothing and an image mosaic based panoramic compensation.The ... A novel image stabilization system is presented,which consists of a global feature point tracking based motion estimation,a Kalman filtering based motion smoothing and an image mosaic based panoramic compensation.The global motion is estimated using feature point matching and iteration with the least-square method.Then,the Kalman filter is applied to smooth the original motion vectors to effectively alleviate unwanted camera vibrations and follow the intentional camera scan.Lastly,the loss information of im... 展开更多
关键词 Cameras Control theory Kalman filters Motion compensation Motion estimation Optical flows STABILIZATION Video recording
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Coupling Magneto-Electro-Elastic node-based smoothed radial point interpolation method for free vibration and transient analysis of Functionally Graded Magneto-Electro-Elastic structures 被引量:2
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作者 Liming ZHOU Shuhui REN +2 位作者 Bin NIE Guikai GUO Xiangyang CUI 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2020年第1期227-243,共17页
A Coupling Magneto-Electro-Elastic(MEE)Node-based Smoothed Radial Point Interpolation Method(CM-NS-RPIM)was proposed to solve the free vibration and transient responses of Functionally Graded Magneto-Electro-Elastic(F... A Coupling Magneto-Electro-Elastic(MEE)Node-based Smoothed Radial Point Interpolation Method(CM-NS-RPIM)was proposed to solve the free vibration and transient responses of Functionally Graded Magneto-Electro-Elastic(FGMEE)structures.By introducing the modified Newmark method,the displacement,electrical potential and magnetic potential of the structures under transient mechanical loading were obtained.Based on G space theory and the weakened weak(W2)formulation,the equations of the multi-physics coupling problems were derived.Using triangular background elements,the free vibration and transient responses of three numerical examples were studied.Results proved that CM-NS-RPIM performed better than the standard FEM by reducing the overly-stiff of structures.Moreover,CM-NS-RPIM could reduce the number of nodes while guaranteeing the accuracy.Besides,triangular elements could be generated automatically even for complex geometries.Therefore,the effectiveness and validity of CM-NS-RPIM were demonstrated,which were valuable for the design of intelligence devices,such as energy harvesters and sensors. 展开更多
关键词 COUPLING MAGNETO-ELECTRO-ELASTIC node-based smoothed radial point interpolation method Functionally Graded MAGNETO-ELECTRO-ELASTIC Gradient smoothing technique Rayleigh damping Transient responses
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NEW APPROACH FOR RELIABILITY-BASED DESIGN OPTIMIZATION:MINIMUM ERROR POINT 被引量:5
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作者 LIU Deshun YUE Wenhui +1 位作者 ZHU Pingyu DU Xiaoping 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2006年第4期514-518,共5页
Conventional reliability-based design optimization (RBDO) requires to use the most probable point (MPP) method for a probabilistic analysis of the reliability constraints. A new approach is presented, called as th... Conventional reliability-based design optimization (RBDO) requires to use the most probable point (MPP) method for a probabilistic analysis of the reliability constraints. A new approach is presented, called as the minimum error point (MEP) method or the MEP based method, for reliability-based design optimization, whose idea is to minimize the error produced by approximating performance functions. The MEP based method uses the first order Taylor's expansion at MEP instead of MPP. Examples demonstrate that the MEP based design optimization can ensure product reliability at the required level, which is very imperative for many important engineering systems. The MEP based reliability design optimization method is feasible and is considered as an alternative for solving reliability design optimization problems. The MEP based method is more robust than the commonly used MPP based method for some irregular performance functions. 展开更多
关键词 Reliability Most probable point (MPP) Minimum error point (MEP)Reliability-based design optimization (RBDO)
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GRAPHICAL COMPUTING METHOD ON FOUR-BAR LINKAGE(1)——Inflexion Circle,Focal Axis,Ball's Point,Centering-point Curve and Circling-point Curve For Four ISPs,Coupler Curves Based on Ball's Points——
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作者 周晋康 《苏州大学学报(工科版)》 CAS 1992年第S2期27-34,共8页
By means of programs GTMPAC based- on generalized triangle method,analysis and synthesis of mechanism design in accordance with absolutely graphicalmethod( absolutely germetrical method) are developed.In this paper,we... By means of programs GTMPAC based- on generalized triangle method,analysis and synthesis of mechanism design in accordance with absolutely graphicalmethod( absolutely germetrical method) are developed.In this paper,we make aspecial study about centering- point curve and circling- point curve and couplercurves based on Ball’s points. 展开更多
关键词 Ball’s point centering - point CURVE and CIRCLING CURVE four ISPS Coupler curves based on BALLS points
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On the Angular Distribution of the Representative Points of Bases of Human Protein Coding Sequences
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作者 Zhou Guoxiang Wang Aikun He Wenchen(Mathematics and Physics Department,Hebei University of Technology, 300130, Tianjin, China) 《河北工业大学学报》 CAS 1997年第A01期1-4,共4页
A novel diagrammtic method is proposed to show the angular distribution of bases of human protein sequences. Using this method, the distribution sphere[1-4] is divided into four regions with same volume. The picture i... A novel diagrammtic method is proposed to show the angular distribution of bases of human protein sequences. Using this method, the distribution sphere[1-4] is divided into four regions with same volume. The picture is clearer and more intuitive than that in [1] .A rule on the angular distribution of the representative points of bases of protein sequences is given. Besides, in 300 representative pointS of human protein sequence samples we find that there are three (not only one) points outside the sphere. 展开更多
关键词 ANGULAR DISTRIBUTION REPRESENTATIVE point of baseS of protein CODING sequence/ DISTRIBUTION SPHERE
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On Point-Based Haptic Rendering
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作者 Shi Wen Shahram Payandeh 《Engineering(科研)》 2013年第5期14-24,共11页
Haptic rendering is referred to as an approach for complementing graphical model of the virtual object with mechanics- based properties. As a result, when the user interacts with the virtual object through a haptic de... Haptic rendering is referred to as an approach for complementing graphical model of the virtual object with mechanics- based properties. As a result, when the user interacts with the virtual object through a haptic device, the object can graphically deflect or deform following laws of mechanics. In addition, the user is able to feel the resulting interaction force when interacting with the virtual object. This paper presents a study of defining the levels-of-detail (LOD) in point-based computational mechanics for haptic rendering of objects. The approach uses the description of object as a set of sampled points. In comparison with the finite element method (FEM), point-based approach does not rely on any predefined mesh representation and depends on the point representation of the volume of the object. Different from solving the governing equations of motion representing the entire object based on pre-defined mesh representation which is used in FEM, in point-based modeling approach, the number of points involved in the computation of displacement/deformation can be adaptively defined during the solution cycle. This frame work can offer the implementation of the notion for levels-of-detail techniques for which can be used to tune the haptic rendering environment for in- creased realism and computational efficiency. This paper presents some initial experimental studies in implementing LOD in such environment. 展开更多
关键词 HAPTIC RENDERING COMPUTATIONAL MECHANICS point-based MODELING Level-of-Details
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病种点数法驱动公立医院绩效体系建设探索
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作者 李青 陈卓杨 万武 《中国医院》 北大核心 2026年第5期12-15,共4页
目的:探讨病种点数法解决DRG支付下公立医院绩效管理中技术价值量化失真问题的有效性。方法:构建技术价值、资源效率和质量安全三维指标体系与阶段性动态核算模型,以246837例住院病例为样本进行验证。结果:病种点数法通过CMI加权与消耗... 目的:探讨病种点数法解决DRG支付下公立医院绩效管理中技术价值量化失真问题的有效性。方法:构建技术价值、资源效率和质量安全三维指标体系与阶段性动态核算模型,以246837例住院病例为样本进行验证。结果:病种点数法通过CMI加权与消耗指数约束实现难度、价值和效率高度匹配(r=0.836,P<0.001);推动CMI值提升6.91%,费用消耗指数下降6.17%,三四级手术量增长49.82%,不良事件率下降14.93%;在资源配置、成本控制与技术价值体现方面显著优于传统方法(P<0.05)。结论:该方法为公立医院提供了精细化绩效管理的可复制框架,有效平衡了成本控制与价值补偿,助力医院向高难度、高效率、高质量方向转型。 展开更多
关键词 公立医院 DRG 病种点数法 绩效管理 医保支付改革 价值医疗
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Interaction Rule between Rare Earths and LowMelting Point Elements in Fe-,Cu-,AI-,Ni-Base Liquid Solutions 被引量:1
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作者 Du Ting Sun Yunyong +1 位作者 Wu Yeming Wang Longmei 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 1997年第1期15-18,共5页
Interaction rule between representative RE and Sn, Sb, Pb, Cu, S, P low melting point elements respectively in Fe , Cu , Al , Ni base liquid solutions including totally 34 ternary and quarternary systems was inve... Interaction rule between representative RE and Sn, Sb, Pb, Cu, S, P low melting point elements respectively in Fe , Cu , Al , Ni base liquid solutions including totally 34 ternary and quarternary systems was investigated. For each system some thermodynamic properties were obtained, such as the standard free energies of equilibrium reactions, activity interaction coefficients etc .. 展开更多
关键词 rare earth low melting point element FE CU Al and Ni base solution interaction rule
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DRG/DIP与RBRVS融合的病种点数法应用研究
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作者 冯欣 李洪丽 尹世钦 《中国医院》 北大核心 2026年第5期1-4,共4页
目的:探讨融合DRG/DIP与RBRVS的病种点数法在医疗劳动价值评估中的应用,解决现有支付模式下劳动价值量化不足的问题。方法:以DRG/DIP分组逻辑为基础,整合RBRVS价值评估体系,通过确定组内诊疗项目、对应RBRVS点值、区分主要贡献者、计算... 目的:探讨融合DRG/DIP与RBRVS的病种点数法在医疗劳动价值评估中的应用,解决现有支付模式下劳动价值量化不足的问题。方法:以DRG/DIP分组逻辑为基础,整合RBRVS价值评估体系,通过确定组内诊疗项目、对应RBRVS点值、区分主要贡献者、计算新“病种点数”等步骤,精准反映医务人员贡献度。结果:构建了融合评估框架;通过随机抽样验证数据稳定性,样本量增加后点数波动平缓。结论:该框架既能发挥DRG/DIP宏观控费作用,又能通过RBRVS微观评估劳动价值,实现成本控制与价值补偿平衡。 展开更多
关键词 DRG DIP RBRVS 病种点数法 医疗劳动价值评估
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基于点云序列注意力的三维接触网吊弦缺陷检测
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作者 陈永 安卓奥博 《铁道科学与工程学报》 北大核心 2026年第2期966-976,共11页
接触网作为高速铁路牵引供电装置的核心组成部分,是保持高速列车运行稳定和安全的重要装置。其中,吊弦作为高速铁路列车供电取流的重要高压输电装置之一,其完整性和稳定性直接关系到列车牵引供电质量和行车安全。高速列车运行时,弓网系... 接触网作为高速铁路牵引供电装置的核心组成部分,是保持高速列车运行稳定和安全的重要装置。其中,吊弦作为高速铁路列车供电取流的重要高压输电装置之一,其完整性和稳定性直接关系到列车牵引供电质量和行车安全。高速列车运行时,弓网系统的耦合作用使吊弦处于频繁振动状态,造成部分吊弦在服役中出现断裂、松股等缺陷。针对现有三维点云分割方法存在不能充分利用接触网点云的空间结构特征、难以高效筛选关键部件点云信息,导致接触网部件检测分割不准确的问题,提出了一种基于点云序列注意力Transformer的三维接触网吊弦缺陷检测方法。首先,构建基于序列注意力机制的Transformer点云分割框架,缓解了接触网中零部件非物理连接区域的遮挡问题,同时提升了点云结构分割的精确性。其次,设计栅格点云采样方法,根据吊弦部件的分割结果,完成对噪声点、离群点和背景点的有效滤除。最后,提出改进后的RANSAC吊弦缺陷检测算法,通过吊弦和相关部件点云的三维空间坐标信息,完成对吊弦缺陷的检测。实验结果表明:所提点云模型的接触网部件点云分割F1-score最高,达到95.46%,较DGCNN提高了5.37%,较PAConv提高了4.23%,OA指标较DGCNN和PAConv分别提升5.87%和4.82%。对不同场景下的点云吊弦能够有效识别缺陷种类,提高了点云吊弦缺陷检测的准确性和鲁棒性。 展开更多
关键词 高铁接触网 点云分割 吊弦缺陷检测 点云序列注意力 栅格点云采样
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基于虚拟锚点的室内融合定位方法
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作者 张宇 李泽 +2 位作者 田增山 桂术亮 刘凯凯 《通信学报》 北大核心 2026年第1期27-40,共14页
利用通信信号镜面反射形成的虚拟锚点(VAP)实现终端定位是近年来的一个研究热点。针对终端在定位过程中VAP出现的“生灭”现象,在单输入单输出(SISO)网络中提出了一种基于虚拟锚点的室内融合定位方法。首先,利用状态转移方程提供的先验... 利用通信信号镜面反射形成的虚拟锚点(VAP)实现终端定位是近年来的一个研究热点。针对终端在定位过程中VAP出现的“生灭”现象,在单输入单输出(SISO)网络中提出了一种基于虚拟锚点的室内融合定位方法。首先,利用状态转移方程提供的先验信息,对观测集合中的非镜面杂波进行滤除。其次,利用平面内不同位置的预测观测集和匈牙利算法构建定位模型,并利用群优化算法估计终端的位置。再次,通过融合滤波方法将状态方程提供的先验位置信息与估计的位置进行融合。仿真结果表明,相较于现有方法,所提方法能够有效地提升定位精度。最后,利用软件无线电搭建测试系统,真实环境下的测试结果表明,所提方法可以达到0.47 m的平均定位精度。 展开更多
关键词 室内定位 虚拟锚点 匈牙利算法 融合滤波
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基于目标检测与边缘分割的输电走廊隐患预警方法
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作者 赵振兵 付龙美 +1 位作者 潘逸天 李浩鹏 《电工技术学报》 北大核心 2026年第3期987-998,1011,共13页
输电线路作为电能传输的关键载体,因其具有点多、面广、线长以及暴露于野外等特点,往往面临较高的安全风险,事故频发。针对这一问题,该文提出了一种基于目标检测与边缘分割的输电走廊隐患检测方法。首先,在YOLOv8中引入小目标检测层和SB... 输电线路作为电能传输的关键载体,因其具有点多、面广、线长以及暴露于野外等特点,往往面临较高的安全风险,事故频发。针对这一问题,该文提出了一种基于目标检测与边缘分割的输电走廊隐患检测方法。首先,在YOLOv8中引入小目标检测层和SBA模块,通过选择性聚合边界与语义信息、自适应注意力机制以及双向特征融合,显著优化了多尺度特征表达和目标定位,特别是在小目标检测方面表现突出。采用重参数轻量头和可重参数化卷积,在大幅减少参数数量的同时,提升了参数利用率,有效地弥补了轻量化可能带来的精度损失,为资源受限设备提供了无损优化方案,并利用MPDIoU对CIoU进行了优化。其次,利用分割网络进行电力线边缘提取,并结合杆塔的空间信息,进一步提升了走廊区域划分的准确性。最后,制定了预警方法,对安全区域进行了危险等级划分,有效评估隐患的破坏性。实验结果表明,该文提出的检测模型在mAP50上达到72.1%,相比基线模型提升了3.2个百分点,且优于其他检测方法,该文所采用的利用分割提取电力线边缘的方法能更好地区分前景和背景,该文所提出的预警方法可以有效地评估隐患对电力线的威胁程度。 展开更多
关键词 外力破坏 SBA 重参数轻量头(RSCD) 安全区域 MPDIoU
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基于积分制管理的住院医师规范化培训专业基地绩效考核评价研究
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作者 李翔宇 于宏 韩颖 《中国毕业后医学教育》 2026年第4期296-300,共5页
目的通过积分制绩效考核评价,客观评价同济大学附属第十人民医院各专业基地住院医师规范化培训(简称住培)教学工作情况,为进一步提高教学工作质量,促进住培工作发展提供依据与建议。方法从教学工作量、教学质量、教学评价、教学贡献4个... 目的通过积分制绩效考核评价,客观评价同济大学附属第十人民医院各专业基地住院医师规范化培训(简称住培)教学工作情况,为进一步提高教学工作质量,促进住培工作发展提供依据与建议。方法从教学工作量、教学质量、教学评价、教学贡献4个维度,对该院各专业基地的教学绩效进行量化评估,通过对实施考评两年以来考核评分的比较和分析,进行积分制绩效考核体系的一致性评价和实施效果评价。结果本研究所设计的积分制绩效考核评分可以较好地评价各专业基地的教学工作情况;实施住培专业基地积分制绩效考核体系后,医院的住培教学水平和质量显著提升。结论积分制绩效考核评分是量化教学工作的有效工具,可根据专业基地的得分来了解和考核其综合表现,并将其与绩效挂钩,从而调动专业基地主观能动性与工作积极性,实现既定管理目标。 展开更多
关键词 住院医师规范化培训 专业基地 量化考核体系 绩效考核 教学管理
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一种基于多策略融合改进的北极海雀优化算法
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作者 陈雅 《火力与指挥控制》 北大核心 2026年第1期56-65,72,共11页
为解决北极海雀优化算法(arctic puffin optimization,APO)在迭代过程中出现的收敛精度低、收敛速度慢、易陷入局部寻优等多种问题,提出一种基于多策略融合改进的北极海雀优化算法(improved arctic puffin optimization algorithm based... 为解决北极海雀优化算法(arctic puffin optimization,APO)在迭代过程中出现的收敛精度低、收敛速度慢、易陷入局部寻优等多种问题,提出一种基于多策略融合改进的北极海雀优化算法(improved arctic puffin optimization algorithm based on multi-strategy fusion,IAPO)。在种群初始化阶段引入佳点集策略,通过借助佳点集数学特性优势,可以在特定搜索空间内生成均匀分布的种群节点。在每次迭代过程开始前,使用基于透镜成像原理的反向学习对每次迭代更新之后的种群、最优种群进行重新计算,找到优质的反向解,使得反向解更具有动态性和灵活性。在北极海雀算法的水下觅食阶段引入动态柯西变异策略,其长尾特性能够使得变异产生较大扰动,从而避免算法陷入局部寻优,增强算法的全局搜索能力。在仿真实验部分,将IAPO与APO、PSO、HBA、RBMO、POA以及其他3种单策略变体算法,分别在CEC2005测试函数集上进行测试,结果表明,IAPO算法的综合性能均优于其他对比算法。 展开更多
关键词 北极海雀优化算法 佳点集 基于透镜成像原理的反向学习 动态柯西变异策略 多策略融合
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不同铁基填料对农业面源氮磷污染的拦截效应及机理分析
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作者 李典 何席伟 +4 位作者 郭文景 马曙云 张志勇 张迎颖 闻学政 《环境科学研究》 北大核心 2026年第3期673-685,共13页
铁基填料广泛应用于农业面源氮磷污染的防治,但不同铁基填料对于氮磷的拦截效果及其机制差异仍不清楚。因此,本研究选择常用的3种市售铁基填料-赤铁矿、磁铁矿、铁屑构建透水坝,在稻季开展农田退水氮磷的沟渠拦截试验,并联用多重表征方... 铁基填料广泛应用于农业面源氮磷污染的防治,但不同铁基填料对于氮磷的拦截效果及其机制差异仍不清楚。因此,本研究选择常用的3种市售铁基填料-赤铁矿、磁铁矿、铁屑构建透水坝,在稻季开展农田退水氮磷的沟渠拦截试验,并联用多重表征方法和微生物群落分析方法探究其机制差异。结果表明:(1)赤铁矿对NO_(3)^(-)-N、NH_(4)^(+)-N、TN和TP的削减率分别可达21.01%±15.91%、18.48%±7.55%、19.18%±16.92%和20.90%±10.52%,均优于磁铁矿和铁屑。(2)赤铁矿和磁铁矿通过定殖微生物,利用还原、硝化和反硝化过程实现对氮的消纳净化,其表面Fe价态转换驱动的氧化沉淀及表面络合过程实现了对磷的拦截。(3)市售铁屑表面钝化层导致其通过微弱的微生物活动对氮磷进行拦截净化。研究显示,在农业面源退水的局部好氧/缺氧/厌氧微环境下,填料表面铁价态差异调控了对应的微生物活动和氧化/还原过程,最终影响了氮磷的拦截效果。 展开更多
关键词 铁基填料 农业面源污染 氮磷 赤铁矿
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交通类专业毕业设计(论文)教学模式改革与评价研究
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作者 吴彪 李荣 +3 位作者 张鹏 苏清源 田芳 孙远涛 《高教学刊》 2026年第1期133-137,共5页
以应用型人才培养为中心,交通行业人才需求为导向,探索创新有效的毕业设计(论文)教学模式及评价体系。围绕工程教育专业认证对交通类专业毕业要求,分析毕业设计(论文)对交通类人才培养目标支撑作用,构建基于毕业要求指标点毕业设计过程... 以应用型人才培养为中心,交通行业人才需求为导向,探索创新有效的毕业设计(论文)教学模式及评价体系。围绕工程教育专业认证对交通类专业毕业要求,分析毕业设计(论文)对交通类人才培养目标支撑作用,构建基于毕业要求指标点毕业设计过程管理模式。校企联合培养贯穿毕业设计全过程,教师科研团队同企业深度合作推动毕业设计选题多元化;全过程引入企业导师的双师型团队联合培养模式,有助于学生开展毕业设计中新技术、新工艺运用从而更加贴合企业需求,也有效提升团队合作及工程意识,且更契合专业认证中毕业能力要求。基于毕业要求指标点,应用层次分析法构建毕业设计(论文)质量评价体系,对改革模式的毕业设计(论文)进行相对客观的评价。评价结果显示,改革毕业设计(论文)模式取得良好成效。5年的实践教学成果表明,团队所进行的毕业设计(论文)教学模式改革对交通类专业人才培养提高具有参考意义。 展开更多
关键词 毕业设计(论文) 指标点 过程管理模式 团队联合指导 评价体系
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