期刊文献+
共找到646篇文章
< 1 2 33 >
每页显示 20 50 100
Signal Classification Method Based on Support Vector Machine and High-Order Cumulants 被引量:1
1
作者 Xin ZHOU Ying WU Bin YANG 《Wireless Sensor Network》 2010年第1期48-52,共5页
In this paper, a classification method based on Support Vector Machine (SVM) is given in the digital modulation signal classification. The second, fourth and sixth order cumulants of the received signals are used as c... In this paper, a classification method based on Support Vector Machine (SVM) is given in the digital modulation signal classification. The second, fourth and sixth order cumulants of the received signals are used as classification vectors firstly, then the kernel thought is used to map the feature vector to the high dimensional feature space and the optimum separating hyperplane is constructed in space to realize signal recognition. In order to build an effective and robust SVM classifier, the radial basis kernel function is selected, one against one or one against rest of multi-class classifier is designed, and method of parameter selection using cross- validation grid is adopted. Through the experiments it can be concluded that the classifier based on SVM has high performance and is more robust. 展开更多
关键词 HIGH-order CUMULANTS Support vector Machine KERNEL Function SIGNAL Classification
在线阅读 下载PDF
Maps to Ordered Topological Vector Spaces and Stratifiable Spaces
2
作者 Erguang YANG Yun XU 《Journal of Mathematical Research with Applications》 CSCD 2018年第1期77-84,共8页
In the paper [Monotone countable paracompactness and maps to ordered topological vector spaces, Top. Appl., 2014, 169(3): 51–70], Yamazaki initiated the study on maps with values into ordered topological vector sp... In the paper [Monotone countable paracompactness and maps to ordered topological vector spaces, Top. Appl., 2014, 169(3): 51–70], Yamazaki initiated the study on maps with values into ordered topological vector spaces. Characterizations of monotonically countably paracompact spaces and some other spaces in terms of maps to ordered topological vector spaces were obtained. In this paper, following Yamazaki's method, we present some characterizations of stratifiable spaces and k-semi-stratifiable spaces in terms of maps with values into ordered topological vector spaces. 展开更多
关键词 stratifiable spaces k-semi-stratifiable spaces maps to ordered topological vector spaces lower(upper) semi-continuity
原文传递
Generalization of the Second Order Vector Potential Formulation for Arbitrary Non-Orthogonal Curvilinear Coordinates Systems from the Covariant Form of Maxwell's Equations
3
作者 Denis Prémel 《Journal of Electromagnetic Analysis and Applications》 2012年第10期400-409,共10页
A great number of semi-analytical models, notably the representation of electromagnetic fields by integral equations are based on the second order vector potential (SOVP) formalism which introduces two scalar potentia... A great number of semi-analytical models, notably the representation of electromagnetic fields by integral equations are based on the second order vector potential (SOVP) formalism which introduces two scalar potentials in order to obtain analytical expressions of the electromagnetic fields from the two potentials. However, the scalar decomposition is often known for canonical coordinate systems. This paper aims in introducing a specific SOVP formulation dedicated to arbitrary non-orthogonal curvilinear coordinates systems. The electromagnetic field representation which is derived in this paper constitutes the key stone for the development of semi-analytical models for solving some eddy currents moelling problems and electromagnetic radiation problems considering at least two homogeneous media separated by a rough interface. This SOVP formulation is derived from the tensor formalism and Maxwell’s equations written in a non-orthogonal coordinates system adapted to a surface characterized by a 2D arbitrary aperiodic profile. 展开更多
关键词 Second order vector Potential (SOVP) Curvilinear COORDINATE System EDDY Current NON-DESTRUCTIVE Testing (ECNDT)
在线阅读 下载PDF
Stationary Probability Vectors of the Second Order Markov Chains
4
作者 DENG Aiping QU Zhiqiang +1 位作者 MA Hongcai GONG Xiaoyue 《Journal of Donghua University(English Edition)》 EI CAS 2019年第6期580-585,共6页
The stationary probability vectors of a second order Markov chain on the(n-1)-dimensional standard simplex are considered.In 2015,Li and Zhang gave a characterization of the second order Markov chain such that every v... The stationary probability vectors of a second order Markov chain on the(n-1)-dimensional standard simplex are considered.In 2015,Li and Zhang gave a characterization of the second order Markov chain such that every vector in the simplex is a stationary vector.A modification of the characterization is presented in the paper.Some sufficient conditions are derived for any facet of the simplex such that every vector of the facet is a stationary vector. 展开更多
关键词 second order MARKOV chain STATIONARY PROBABILITY vector SIMPLEX MARKOV operator FACET
在线阅读 下载PDF
Higher-Order Minimizers and Generalized (F,<i>ρ</i>)-Convexity in Nonsmooth Vector Optimization over Cones
5
作者 S. K. Suneja Sunila Sharma Malti Kapoor 《Applied Mathematics》 2015年第1期7-19,共13页
In this paper, we introduce the concept of a (weak) minimizer of order k for a nonsmooth vector optimization problem over cones. Generalized classes of higher-order cone-nonsmooth (F, ρ)-convex functions are introduc... In this paper, we introduce the concept of a (weak) minimizer of order k for a nonsmooth vector optimization problem over cones. Generalized classes of higher-order cone-nonsmooth (F, ρ)-convex functions are introduced and sufficient optimality results are proved involving these classes. Also, a unified dual is associated with the considered primal problem, and weak and strong duality results are established. 展开更多
关键词 NONSMOOTH vector Optimization OVER CONES (Weak) MINIMIZERS of order k NONSMOOTH (F ρ)-Convex Function of order k
在线阅读 下载PDF
A New Hybrid Order Approach to Morphological Color Image Processing Based on Reduced Order with Adaptive Absolute Reference
6
作者 S. Ouattara A. Kouassi +3 位作者 J. C. Okaingni A. Koffi G. Loum A. Clement 《Engineering(科研)》 2016年第9期633-645,共14页
Mathematical morphology can process the binary and grayscale image successfully. This theory cannot be extended to the color image directly. In color space, a vector represents a pixel, so in order to compare vectors,... Mathematical morphology can process the binary and grayscale image successfully. This theory cannot be extended to the color image directly. In color space, a vector represents a pixel, so in order to compare vectors, vectoriel orderings must be defined first. This paper addresses the question of the extension of morphological operator to the case of color images. The proposed method used the order by bit mixing to replace the conditional order. Our order is based on a combination of reduced and bit mixing ordering of the underlying data. Additionally it is a total ordering. Since it not only solves the problems of false color generated by the marginal order but also those of multiple extrema generated by reduced order. The performance of the introduced operators is illustrated by means of different applications: color gradients for segmenting, image smoothing (noise suppression) by median filter operator and Laplacian operators. Examples of natural color images and synthetic color images are given. Experimental results show the improvement brought by this new method. 展开更多
关键词 Multicomponent Image vector order Adaptive Absolute Referent Bit Mixing Morphological Operators
在线阅读 下载PDF
Flux vector splitting solutions for coupling hydraulic transient of gas-liquid-solid three-phase flow in pipelines 被引量:3
7
作者 陈明 焦光伟 +1 位作者 邓松圣 王建华 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2013年第7期811-822,共12页
The gas-liquid-solid three-phase mixed flow is the most general in multiphase mixed transportation. It is significant to exactly solve the coupling hydraulic transient problems of this type of multiphase mixed flow in... The gas-liquid-solid three-phase mixed flow is the most general in multiphase mixed transportation. It is significant to exactly solve the coupling hydraulic transient problems of this type of multiphase mixed flow in pipelines. Presently, the method of characteristics is widely used to solve classical hydraulic transient problems. However, when it is used to solve coupling hydraulic transient problems, excessive interpolation errors may be introduced into the results due to unavoidable multiwave interpolated calculations. To deal with the problem, a finite difference scheme based on the Steger- Warming flux vector splitting is proposed. A flux vector splitting scheme is established for the coupling hydraulic transient model of gas-liquid-solid three-phase mixed flow in the pipelines. The flux subvectors are then discretized by the Lax-Wendroff central difference scheme and the Warming-Beam upwind difference scheme with second-order precision in both time and space. Under the Rankine-Hugoniot conditions and the corresponding boundary conditions, an effective solution to those points located at the boundaries is developed, which can avoid the problem beyond the calculation region directly induced by the second-order discrete technique. Numerical and experimental verifications indicate that the proposed scheme has several desirable advantages including high calculation precision, excellent shock wave capture capability without false numerical oscillation, low sensitivity to the Courant number, and good stability. 展开更多
关键词 gas-liquid-solid three-phase flow fluid-structure interaction hydraulic transient flux vector splitting second-order precision
在线阅读 下载PDF
Robust Source Localization in Shallow Water Based on Vector Optimization
8
作者 宋海岩 时洁 刘伯胜 《China Ocean Engineering》 SCIE EI CSCD 2013年第3期379-390,共12页
Owing to the multipath effect, the source localization in shallow water has been an area of active interest. However, most methods for source localization in shallow water are sensitive to the assumed model of the und... Owing to the multipath effect, the source localization in shallow water has been an area of active interest. However, most methods for source localization in shallow water are sensitive to the assumed model of the underwater environment and have poor robustness against the underwater channel uncertainty, which limit their further application in practical engineering. In this paper, a new method of source localization in shallow water, based on vector optimization concept, is described, which is highly robust against environmental factors affecting the localization, such as the channel depth, the bottom reflection coefficients, and so on. Through constructing the uncertainty set of the source vector errors and extracting the multi-path sound rays from the sea surface and bottom, the proposed method can accurately localize one or more sources in shallow water dominated by multipath propagation. It turns out that the natural formulation of our approach involves minimization of two quadratic functions subject to infinitely many nonconvex quadratic constraints. It shows that this problem (originally intractable) can be reformulated in a convex form as the so-called second-order cone program (SOCP) and solved efficiently by using the well-established interior point method, such as the sottware tool, SeDuMi. Computer simulations show better performance of the proposed method as compared with existing algorithms and establish a theoretical foundation for the practical engineering application. 展开更多
关键词 source localization in shallow water ROBUST HIGH-RESOLUTION vector optimization second-order coneprogramming
在线阅读 下载PDF
Approach to a Fifth-Order Boundary Value Problem, via Sperner's Lemma
9
作者 Panos K. Palamides Evgenia H. Papageorgiou 《Applied Mathematics》 2011年第8期993-998,共6页
We consider the five-point boundary value problem for a fifth-order differential equation, where the nonlinearity is superlinear at both the origin and +infinity. Our method of proof combines the Kneser’s theorem wit... We consider the five-point boundary value problem for a fifth-order differential equation, where the nonlinearity is superlinear at both the origin and +infinity. Our method of proof combines the Kneser’s theorem with the well-known from combinatorial topology Sperner’s lemma. We also notice that our geometric approach is strongly based on the associated vector field. 展开更多
关键词 Fifth-order Differential Equation vector Field Kneser’s THEOREM Sperner’s LEMMA
在线阅读 下载PDF
Neuropathology Classifier Based on Higher Order Spectra
10
作者 Cesar Seijas Antonino Caralli Sergio Villazana 《Journal of Computer and Communications》 2013年第4期28-32,共5页
Epilepsy is the most common neuropathology. Statistical studies related to the disease reported that 20% - 25% of epileptic patients with occurrence of seizures were even under treatment with drugs. This article prese... Epilepsy is the most common neuropathology. Statistical studies related to the disease reported that 20% - 25% of epileptic patients with occurrence of seizures were even under treatment with drugs. This article presents a strategy for improved detection of the neuropathology, based on electroencephalogram (EEG), using a classifier built with support vector machines (SVC). The SVC is designed based on feature extraction of higher order spectra of time series derived from the EEG applied to epileptic patients and control patients. As demonstrated in the study presented, the EEG time series are highly nonlinear and non-Gaussian, therefore, exhibit higher order spectra, which are extracted features that improve the accuracy in the performance of SVC. The results of this study suggest the development of highly accurate computational tools for the diagnosis of this dreaded neuropathology. 展开更多
关键词 HIGHER order SPECTRA Classification Support vector MACHINES EEG EPILEPSY
暂未订购
Higher-Order Duality for Minimax Fractional Type Programming Involving Symmetric Matrices
11
作者 Caiyun Jin Cao-Zong Cheng 《Applied Mathematics》 2011年第11期1387-1392,共6页
Convexity and generalized convexity play important roles in optimization theory. With the development of programming problem, there has been a growing interest in the higher-order dual problem and a lot of related gen... Convexity and generalized convexity play important roles in optimization theory. With the development of programming problem, there has been a growing interest in the higher-order dual problem and a lot of related generalized convexities are given. In this paper, we give the convexity of (F, α ,p ,d ,b , φ )β vector-pseudo- quasi-Type I and formulate a higher-order duality for minimax fractional type programming involving symmetric matrices, and give the weak, strong and strict converse duality theorems under the condition of higher-order (F, α ,p ,d ,b , φ )β vector-pseudoquasi-Type I. 展开更多
关键词 HIGHER-order (F α p d b φ vector-Pseudoquasi-Type I HIGHER-order DUALITY MINIMAX FRACTIONAL TYPE PROGRAMMING Positive Semidefinite Symmetric Matrix
在线阅读 下载PDF
基于混合八叉树模型的五轴联动数控加工仿真 被引量:2
12
作者 秦金祥 杨萌 《计算机仿真》 2025年第2期271-274,441,共5页
针对因五轴联动数控机床动态特性难捕捉,导致的数控加工仿真难度大的问题,提出一种基于混合八叉树模型的数控加工仿真方法。根据五轴联动中直角轴和旋转轴的同步协调特性,采用线性插补方式,分析五轴联动的旋转角速度和角加速度的对偶变... 针对因五轴联动数控机床动态特性难捕捉,导致的数控加工仿真难度大的问题,提出一种基于混合八叉树模型的数控加工仿真方法。根据五轴联动中直角轴和旋转轴的同步协调特性,采用线性插补方式,分析五轴联动的旋转角速度和角加速度的对偶变化,建立一阶和二阶比例函数计算变化矢量,通过矢量同步关系得到角速度和角加速度同比例变化数值。建立混合八叉树模型,将五轴联动矢量的作为叶结点的初始输入值,其中每个分支和叶结点均代表不同五轴联动的动态参数,通过层次规划和节点分割模拟整个数控加工过程,结合实际应用情况不断迭代更新,实现五轴联动数控加工仿真。实验结果表明,上述方法能够高效仿真五轴联动数控机床的加工过程,对刀尖和刀轴的轨迹模拟效果较好、清晰直观,将其应用在实际的设备维护中可提供重要帮助。 展开更多
关键词 混合八叉树模型 五轴联动 数控加工 二阶变化矢量 层次规划
在线阅读 下载PDF
基于负载观测器的PMSM预测电流控制
13
作者 于树友 盛恩聪 +1 位作者 徐明生 孙晓东 《控制工程》 北大核心 2025年第1期1-11,共11页
针对永磁同步电机(permanent magnet synchronous motor,PMSM)预测电流控制系统在线优化计算负担大和抗负载扰动性能不足的问题,提出了一种基于负载转矩观测器的PMSM预测电流控制策略。首先,基于离散空间矢量调制构建虚拟电压矢量,并利... 针对永磁同步电机(permanent magnet synchronous motor,PMSM)预测电流控制系统在线优化计算负担大和抗负载扰动性能不足的问题,提出了一种基于负载转矩观测器的PMSM预测电流控制策略。首先,基于离散空间矢量调制构建虚拟电压矢量,并利用无差拍的思想对备选电压矢量控制集进行优化,降低电压矢量寻优的计算负担。然后,为了提高系统的抗负载扰动能力,设计降阶观测器对负载转矩进行实时观测,并将负载转矩观测值按比例前馈至电流环,补偿由负载转矩变化引起的电流波动。仿真结果表明,所提电压矢量寻优策略在保证控制效果的同时有效降低了计算负担,降阶观测器的引入明显提高了系统的抗负载扰动能力。 展开更多
关键词 永磁同步电机 预测电流控制 离散空间矢量调制 负载扰动 降阶观测器
原文传递
Optimality conditions in set optimization employing higher-order radial derivatives
14
作者 YU Guo-lin 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2017年第2期225-236,共12页
There are two approaches of defining the solutions of a set-valued optimization problem: vector criterion and set criterion. This note is devoted to higher-order optimality conditions using both criteria of solutions... There are two approaches of defining the solutions of a set-valued optimization problem: vector criterion and set criterion. This note is devoted to higher-order optimality conditions using both criteria of solutions for a constrained set-valued optimization problem in terms of higher-order radial derivatives. In the case of vector criterion, some optimality conditions are derived for isolated (weak) minimizers. With set criterion, necessary and sufficient optimality conditions are established for minimal solutions relative to lower set-order relation. 展开更多
关键词 higher-order radial derivative optimality conditions set-valued optimization vector criterion set criterion.
在线阅读 下载PDF
高阶矢量Bessel涡旋光的传输和自愈特性研究
15
作者 王徐坚 郝晨君 +3 位作者 李昊翔 朱科 高秀敏 庄松林 《光学精密工程》 北大核心 2025年第8期1169-1178,共10页
高阶矢量Bessel涡旋光由于具有无衍射、自愈性以及在其横截面上同时具有各向异性的涡旋偏振分布和螺旋形相位,在信息传输、成像、抗干扰、粒子操控等领域有巨大应用潜力。本文基于模式提取原理和光笔技术,取代传统基于双光束分别调制产... 高阶矢量Bessel涡旋光由于具有无衍射、自愈性以及在其横截面上同时具有各向异性的涡旋偏振分布和螺旋形相位,在信息传输、成像、抗干扰、粒子操控等领域有巨大应用潜力。本文基于模式提取原理和光笔技术,取代传统基于双光束分别调制产生高阶矢量Bessel涡旋光束的方法,仿真计算并实验验证基于单一入射光束提取产生高阶矢量Bessel涡旋光束,对其在自由空间内的传输特性和自愈特性进行了研究。此外,以拓扑数和涡旋光阶数分别取0,1,2为例,对比分析了两者对矢量Bessel涡旋光传输特性和自愈特性的影响。数值模拟和光学实验结果均表明,光束传输过程中,涡旋光阶数和拓扑数的高低不影响其保持中心区域光强不发散的无衍射状态;在遇到阻碍对传播造成破坏后,拓扑数越小的光束,进行自愈所需时间越短。对光学捕获、光学成像、光学通信等领域的应用研究有重要的潜在意义。 展开更多
关键词 高阶矢量Bessel涡旋光 无衍射特性 自愈特性
在线阅读 下载PDF
基于高次时频谱特征的LPI雷达信号识别 被引量:3
16
作者 李世通 金小萍 +1 位作者 孙杰 汪晓锋 《北京航空航天大学学报》 北大核心 2025年第1期314-320,共7页
针对传统LPI雷达信号识别算法在低信噪比下识别率较低的问题,提出了一种基于高次时频特征的雷达信号识别算法。利用时频变换得到雷达信号的时频分布,时频谱做幂次化计算得到信号的高次时频图像,提取时频图像的灰度梯度共生矩阵和伪Zern... 针对传统LPI雷达信号识别算法在低信噪比下识别率较低的问题,提出了一种基于高次时频特征的雷达信号识别算法。利用时频变换得到雷达信号的时频分布,时频谱做幂次化计算得到信号的高次时频图像,提取时频图像的灰度梯度共生矩阵和伪Zernike特征并组成联合特征向量,通过支持向量机实现雷达信号的分类识别。实验结果表明:在信噪比为−6 dB时,所提算法对8种典型雷达信号的整体识别准确率能达到95%以上。 展开更多
关键词 雷达信号识别 时频变换 高次时频 特征提取 支持向量机
原文传递
基于卡尔曼前馈拟合状态观测器的储纬器用永磁同步电动机霍尔位置检测方法
17
作者 孟子钰 鲁文其 +3 位作者 张颂 苗盛鸿 黄富华 彭来湖 《纺织学报》 北大核心 2025年第9期232-241,共10页
基于开关型霍尔位置传感器的永磁同步电动机控制系统虽具有高功率密度、高效率等优势,但该类型传感器的信号跳变离散,使电动机的位置和速度估算出现较大误差,进而影响了储纬器纱线输送的运行性能。为提高电动机转子估算的精度,以增强储... 基于开关型霍尔位置传感器的永磁同步电动机控制系统虽具有高功率密度、高效率等优势,但该类型传感器的信号跳变离散,使电动机的位置和速度估算出现较大误差,进而影响了储纬器纱线输送的运行性能。为提高电动机转子估算的精度,以增强储纬器纱线输送的稳定性,提出了基于卡尔曼前馈拟合状态观测器的电动机转子位置和速度估计方法。首先采用卡尔曼迭代算法对离散的霍尔信号进行滤波及拟合,以消除霍尔安装偏差造成的噪声扰动;其次,采用全维状态观测器对电动机的转子位置信息进行估算,最终获得连续的电动机转子位置和速度信息。为验证提出算法的有效性,搭建实验平台进行了测试。结果表明:相较于传统的线性外插算法,采用改进卡尔曼前馈拟合状态观测器算法的系统,在启动阶段,电动机转子位置及速度的估算精度更高;在整个运行过程,纱线输送的动态性能和稳态性能更好。 展开更多
关键词 霍尔传感器 永磁同步电动机 储纬器 卡尔曼滤波 全维状态观测器 矢量控制
在线阅读 下载PDF
特征提取和筛选下低速制动颤振的评价
18
作者 李天舒 靳畅 +1 位作者 李阳 姜天宇 《振动.测试与诊断》 北大核心 2025年第1期39-44,198,共7页
针对汽车低速制动时的蠕动颤振表现主要依靠人工主观评价,存在成本高、耗时长、易受人员主观性影响等问题,提出了一种基于机器学习模型的智能评价方法。首先,研究并提取了颤振信号的特征;其次,采用支持向量机(support vector machine,简... 针对汽车低速制动时的蠕动颤振表现主要依靠人工主观评价,存在成本高、耗时长、易受人员主观性影响等问题,提出了一种基于机器学习模型的智能评价方法。首先,研究并提取了颤振信号的特征;其次,采用支持向量机(support vector machine,简称SVM)和K近邻算法(K nearest neighbors,简称KNN)2种机器学习模型进行制动颤振的智能评价;然后,提出基于概率密度特征的特征排序与筛选算法,将特征从39维筛选至11维,以提高机器学习模型的准确率;最后,通过对比试验发现,经过特征筛选后的训练机器学习模型SVM和KNN的准确率分别从72.5%和68.75%提升到了86.25%和87.5%。试验结果表明,提出的特征提取和基于概率密度的特征筛选方法在对蠕动颤振评价上具有较高的有效性。 展开更多
关键词 制动颤振 特征提取 特征排序 特征筛选 支持向量机 K近邻
在线阅读 下载PDF
向量变分不等式的高阶可微性与灵敏性
19
作者 马权禄 薛小维 《山东大学学报(理学版)》 北大核心 2025年第2期105-113,共9页
研究向量变分不等式和弱向量变分不等式两类问题的高阶可微性与灵敏性。介绍了相依锥、高阶切集等的基本定义,研究了与向量变分不等式密切相关的一类集值映射的高阶微分性质,得到了其高阶导数的精确计算公式。通过讨论集值映射与其剖面... 研究向量变分不等式和弱向量变分不等式两类问题的高阶可微性与灵敏性。介绍了相依锥、高阶切集等的基本定义,研究了与向量变分不等式密切相关的一类集值映射的高阶微分性质,得到了其高阶导数的精确计算公式。通过讨论集值映射与其剖面映射二者高阶导数之间的关系,得到了向量变分不等式的高阶可微性与灵敏性。 展开更多
关键词 向量变分不等式 高阶切集 相依导数 灵敏性
原文传递
一类非凸向量优化问题关于真非控解的对偶理论
20
作者 马俊涛 游曼雪 《保山学院学报》 2025年第2期20-27,共8页
变动序优化问题在医学图像配准、投资组合优化、环境和行为科学等问题中具有重要应用。研究一类带变序结构的非凸约束向量优化问题,借助一个非线性标量化函数定义与原问题相关的实值增广拉格朗日函数,讨论拉格朗日函数的鞍点性质,根据... 变动序优化问题在医学图像配准、投资组合优化、环境和行为科学等问题中具有重要应用。研究一类带变序结构的非凸约束向量优化问题,借助一个非线性标量化函数定义与原问题相关的实值增广拉格朗日函数,讨论拉格朗日函数的鞍点性质,根据拉格朗日函数的鞍点来刻画给定向量优化问题的Benson型真非控解。根据拉格朗日函数定义原向量优化问题相应的对偶集,并证明了相关的对偶性结果。 展开更多
关键词 向量优化 变序结构 增广拉格朗日函数:鞍点 对偶性
在线阅读 下载PDF
上一页 1 2 33 下一页 到第
使用帮助 返回顶部