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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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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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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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基于薄弱点定位的电力电子化交流配用电系统振荡抑制方法
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作者 沈冰 柴炜 +2 位作者 王凯 李骁远 吕敬 《上海交通大学学报》 北大核心 2026年第1期32-41,I0001,I0002,共12页
近年来,电力电子变流器因其可控性与灵活性等特点,在交流配用电系统中得到大量应用.然而,随着电力电子设备接入比例不断提高,高度电力电子化带来的振荡稳定性问题成为目前新型配用电系统面临的关键技术难题之一.在实际交流配用电系统中,... 近年来,电力电子变流器因其可控性与灵活性等特点,在交流配用电系统中得到大量应用.然而,随着电力电子设备接入比例不断提高,高度电力电子化带来的振荡稳定性问题成为目前新型配用电系统面临的关键技术难题之一.在实际交流配用电系统中,次/超同步振荡问题频发,严重影响工业生产和电网安全稳定运行.为此,提出一种基于薄弱点定位的电力电子化交流配用电系统振荡抑制方法.首先,构建电力电子化交流配用电系统的频域阻抗网络,建立该系统的节点导纳矩阵模型,基于主导特征值分析多机系统的次/超同步稳定性.然后,进一步计算得到系统薄弱模态的节点参与因子矩阵,确定系统薄弱节点,并定义节点耦合度,量化评估节点间的交互作用强弱;最后,提出一种基于直流电压反馈有源阻尼的振荡抑制方法.通过某实际电力电子化交流配用电系统算例验证了所提方法的有效性. 展开更多
关键词 电力电子化电力系统 次同步振荡 薄弱点定位 节点参与因子 频域模态分析
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“三因制宜”中医护理联合耳穴贴压在糖尿病患者中的应用效果
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作者 刘晓宁 李倬怡 +2 位作者 刘苹 高阳 娄静 《临床心身疾病杂志》 2026年第1期140-144,共5页
目的探讨“三因制宜”中医护理联合耳穴贴压在糖尿病患者中的应用效果。方法将162例糖尿病患者随机分为研究组与对照组,各81例。对照组患者给予常规护理,研究组患者在对照组基础上给予“三因制宜”中医护理联合耳穴贴压。干预前后,比较... 目的探讨“三因制宜”中医护理联合耳穴贴压在糖尿病患者中的应用效果。方法将162例糖尿病患者随机分为研究组与对照组,各81例。对照组患者给予常规护理,研究组患者在对照组基础上给予“三因制宜”中医护理联合耳穴贴压。干预前后,比较两组患者的中医证候积分、血糖(空腹血糖、餐后2 h血糖及糖化血红蛋白)水平、自我效能感[糖尿病自我效能感量表(DSES)评分]、生存质量[糖尿病患者生存质量特异性量表(DSQL)评分]。结果干预后,两组患者中医证候总分及各症状评分、空腹血糖水平、餐后2 h血糖水平、糖化血红蛋白水平、DSQL评分较干预前降低,DSES总分及各维度评分较干预前升高,且研究组优于对照组(P<0.01)。结论“三因制宜”中医护理联合耳穴贴压可改善糖尿病患者症状,降低血糖水平,提高其自我效能感与生存质量。 展开更多
关键词 三因制宜 耳穴贴压 糖尿病 血糖水平 自我效能感
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基于激光点云的钢桥拼接板螺孔信息智能提取
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作者 赵训刚 郑党鑫 +2 位作者 钟继卫 李艳哲 李逸 《世界桥梁》 北大核心 2026年第1期61-67,共7页
针对当前栓接钢桥数字化拼装过程中螺孔信息提取自动化程度低、主观性高、处理速度慢等问题,提出一种融合三维点云曲率、投影、密度聚类与随机采样一致性(RANSAC)算法的螺孔信息智能检测算法。首先通过点云曲率得到螺孔的投影底面;其次... 针对当前栓接钢桥数字化拼装过程中螺孔信息提取自动化程度低、主观性高、处理速度慢等问题,提出一种融合三维点云曲率、投影、密度聚类与随机采样一致性(RANSAC)算法的螺孔信息智能检测算法。首先通过点云曲率得到螺孔的投影底面;其次将点云按照平面的法向方向投影,得到投影点云;然后使用分层密度聚类(HDBSCAN)算法对投影点云进行聚类,得到底面圆孔点云的聚类分割结果并进行统计滤波,去除离群点;最后使用RANSAC算法对聚类中的点进行圆孔拟合,获取每个螺孔的底面圆心坐标与半径。以某特大钢桥的桁段下弦杆拼接板为试验对象,将所提算法与商业软件人工交互对比,结果表明:螺孔圆心空间距离的平均偏差为0.06 mm,个别点的最大偏差仅为0.17 mm,满足工程精度要求;在速度方面,相较于人工操作需耗时1 h以上,所提算法仅用2 min即可完成计算。 展开更多
关键词 钢桥 栓接 拼接板 数字化拼装 螺孔信息智能检测 点云曲率 密度聚类 RANSAC螺孔拟合
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多变点检测问题的Shape-based BS算法 被引量:5
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作者 庄丹 刘友波 马铁丰 《高校应用数学学报(A辑)》 北大核心 2019年第2期151-164,共14页
BS算法是时间序列多变点检测中最经典的算法之一,但是基于全局CUSUM统计量的识别过程会带来过多误判和较高的时间复杂度.BS算法是一种离线的序贯方法,因此没有充分利用数据的时序信息;另一方面,BS算法识别变点的原则是CUSUM统计量最大化... BS算法是时间序列多变点检测中最经典的算法之一,但是基于全局CUSUM统计量的识别过程会带来过多误判和较高的时间复杂度.BS算法是一种离线的序贯方法,因此没有充分利用数据的时序信息;另一方面,BS算法识别变点的原则是CUSUM统计量最大化,也没有考虑统计量构成序列的形态特性.鉴于此,提出一种基于局部形态识别的BS改进算法,命名为Shape-based BS算法.基于局部形态识别统计量,不仅大大降低计算复杂度,且降低了因变点间的互相干扰而带来的误判率,进而提升变点识别的稳健性.最后,将此算法应用到了电力系统的"场景压缩"问题上,具有满意的实用效果. 展开更多
关键词 多变点检测 Shape-based BS算法 形态识别 场景压缩
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Effect of Strong Basic Oxide( Li2O,Na2O,K2O and BaO)on Property of CaO-Based Flux 被引量:8
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作者 LI Gui-rong 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2003年第3期6-9,共4页
It is found that strong basic oxides including Li2O,Na2O,K2O and BaO,which are used to replace a part of CaO in CaO-based fluxes,can lower the melting point and the viscosity and enhance the dephosphorizing ability. T... It is found that strong basic oxides including Li2O,Na2O,K2O and BaO,which are used to replace a part of CaO in CaO-based fluxes,can lower the melting point and the viscosity and enhance the dephosphorizing ability. The mechanism was analysed and the addition of Li2O to CaO based fluxes was recommended. 展开更多
关键词 strong basic oxide CaO-based flux melting point viscosity dephosphorizing ability
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基于Expectile-based VaR变点检测的金融传染分析 被引量:8
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作者 谭常春 操毅文 叶五一 《数理统计与管理》 CSSCI 北大核心 2018年第2期371-380,共10页
本文在分位点回归的基础上采用ALS方法,建立了线性Expectile模型,并以此计算美国金融危机期间有关经济体的Expectile-based VaR(EVaR),对EVaR进行变点检测。根据变点的位置来估计危机发生的时间,并通过比较模型的系数在危机前后... 本文在分位点回归的基础上采用ALS方法,建立了线性Expectile模型,并以此计算美国金融危机期间有关经济体的Expectile-based VaR(EVaR),对EVaR进行变点检测。根据变点的位置来估计危机发生的时间,并通过比较模型的系数在危机前后的变化情况,分析了美国金融危机对中国、香港、英国、德国和日本造成的传染情况。同时结合实际情况分析线性Expectile模型所确定的危机发生时间和系数变化所反映的危机传染性强弱程度,并与斜率模型得到的结论进行比较,体现了线性Expectile模型的准确性。 展开更多
关键词 分位点回归模型 预期位在险价值 变点 金融传染
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Triplet Label Based Image Retrieval Using Deep Learning in Large Database 被引量:1
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作者 K.Nithya V.Rajamani 《Computer Systems Science & Engineering》 SCIE EI 2023年第3期2655-2666,共12页
Recent days,Image retrieval has become a tedious process as the image database has grown very larger.The introduction of Machine Learning(ML)and Deep Learning(DL)made this process more comfortable.In these,the pair-wi... Recent days,Image retrieval has become a tedious process as the image database has grown very larger.The introduction of Machine Learning(ML)and Deep Learning(DL)made this process more comfortable.In these,the pair-wise label similarity is used tofind the matching images from the database.But this method lacks of limited propose code and weak execution of misclassified images.In order to get-rid of the above problem,a novel triplet based label that incorporates context-spatial similarity measure is proposed.A Point Attention Based Triplet Network(PABTN)is introduced to study propose code that gives maximum discriminative ability.To improve the performance of ranking,a corre-lating resolutions for the classification,triplet labels based onfindings,a spatial-attention mechanism and Region Of Interest(ROI)and small trial information loss containing a new triplet cross-entropy loss are used.From the experimental results,it is shown that the proposed technique exhibits better results in terms of mean Reciprocal Rank(mRR)and mean Average Precision(mAP)in the CIFAR-10 and NUS-WIPE datasets. 展开更多
关键词 Image retrieval deep learning point attention based triplet network correlating resolutions classification region of interest
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RSSI-based Algorithm for Indoor Localization 被引量:9
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作者 Xiuyan Zhu Yuan Feng 《Communications and Network》 2013年第2期37-42,共6页
Wireless node localization is one of the key technologies for wireless sensor networks. Outdoor localization can use GPS, AGPS (Assisted Global Positioning System) [6], but in buildings like supermarkets and undergrou... Wireless node localization is one of the key technologies for wireless sensor networks. Outdoor localization can use GPS, AGPS (Assisted Global Positioning System) [6], but in buildings like supermarkets and underground parking, the accuracy of GPS and even AGPS will be greatly reduced. Since Indoor localization requests higher accuracy, using GPS or AGPS for indoor localization is not feasible in the current view. RSSI-based trilateral localization algorithm, due to its low cost, no additional hardware support, and easy-understanding, it becomes the mainstream localization algorithm in wireless sensor networks. With the development of wireless sensor networks and smart devices, the number of WIFI access point in these buildings is increasing, as long as a mobile smart device can detect three or three more known WIFI hotspots’ positions, it would be relatively easy to realize self-localization (Usually WIFI access points locations are fixed). The key problem is that the RSSI value is relatively vulnerable to the influence of the physical environment, causing large calculation error in RSSI-based localization algorithm. The paper proposes an improved RSSI-based algorithm, the experimental results show that compared with original RSSI-based localization algorithms the algorithm improves the localization accuracy and reduces the deviation. 展开更多
关键词 INDOOR LOCALIZATION Algorithm RSSI-based WIFI Access point Smart Phones
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