期刊文献+
共找到5篇文章
< 1 >
每页显示 20 50 100
点接触混合润滑的数值求解方法 被引量:4
1
作者 罗剑 赵三星 《润滑与密封》 CAS CSCD 北大核心 2017年第6期35-39,共5页
基于半系统法的统一Reynolds方程,对点接触混合润滑进行数值模拟。在流体润滑区,采用Reynolds方程求解流体压力,在固体接触区采用简化Reynolds方程求解压力。弹性变形使用离散卷积-快速傅里叶变换(DC-FFT)计算。为了加快迭代收敛速度,... 基于半系统法的统一Reynolds方程,对点接触混合润滑进行数值模拟。在流体润滑区,采用Reynolds方程求解流体压力,在固体接触区采用简化Reynolds方程求解压力。弹性变形使用离散卷积-快速傅里叶变换(DC-FFT)计算。为了加快迭代收敛速度,在数值求解过程中使用渐进网格加密(Progressive Mesh Densification,PMD)算法。数值模拟结果表明,该模型可以快速地求解光滑和粗糙表面条件下的各种润滑情况,包括全膜、混合和边界润滑;随着卷吸速度的增加,润滑状态从边界到混合再到全膜润滑是个光滑过渡的过程。 展开更多
关键词 半系统法 混合润滑 点接触 渐进网格加密算
下载PDF
Semiparametric Regression and Model Refining 被引量:13
2
作者 SUN Haiyan WU Yun 《Geo-Spatial Information Science》 2002年第4期10-13,共4页
This paper presents a semiparametric adjustment method suitable for general cases.Assuming that the regularizer matrix is positive definite,the calculation method is discussed and the corresponding formulae are presen... This paper presents a semiparametric adjustment method suitable for general cases.Assuming that the regularizer matrix is positive definite,the calculation method is discussed and the corresponding formulae are presented.Finally,a simulated adjustment problem is constructed to explain the method given in this paper.The results from the semiparametric model and G_M model are compared.The results demonstrate that the model errors or the systematic errors of the observations can be detected correctly with the semiparametric estimate method. 展开更多
关键词 model error systematric error semiparametric regression model refine regularizer matrix smoothing parameter
下载PDF
Observer-based hybrid control algorithm for semi-active suspension systems 被引量:2
3
作者 REN Hong-bin CHEN Si-zhong +2 位作者 ZHAO Yu-zhuang LIU Gang YANG Lin 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第9期2268-2275,共8页
In order to improve ride comfort and handling performance of the vehicle, an adaptive hybrid control algorithm is proposed for semi-active suspension systems. The virtues of sky-hook is combined with ground-hook contr... In order to improve ride comfort and handling performance of the vehicle, an adaptive hybrid control algorithm is proposed for semi-active suspension systems. The virtues of sky-hook is combined with ground-hook control strategies and a more suitable compromise for the suspension systems is chosen. The hybrid coefficient is tuned according to the longitudinal and lateral acceleration so as to improve the vehicle stability especially in high speed conditions. Damping continuous adjustable absorber is used to continuously control the damping force so as to eliminate the damping force jerk instead of traditional on-off control policy. Based on suspension stroke measured by sensors, unscented Kalman filter is designed to estimate the suspension states in real-time for the realization of hybrid control, which improves the robustness of the control strategy and is adaptive to different types of road profiles. Finally, the proposed control algorithm is validated under the following two typical road profiles: half-sine speed bump road and the random road. The simulation results indicate that the hybrid control algorithm could offer a good coordination between ride comfort and handling of the vehicle. 展开更多
关键词 semi-active suspension hybrid control unscented Kalman filter (UKF)
下载PDF
Semi-blind Channel Estimator for OFDM-STC
4
作者 吴赟 罗汉文 +1 位作者 宋文涛 黄建国 《Journal of Shanghai Jiaotong university(Science)》 EI 2007年第2期229-233,共5页
Channel state information of OFDM-STC system is required for maximum likelihood decoding.A subspace-based semi-blind method was proposed for estimating the channels of OFDM-STC systems.The channels are first estimated... Channel state information of OFDM-STC system is required for maximum likelihood decoding.A subspace-based semi-blind method was proposed for estimating the channels of OFDM-STC systems.The channels are first estimated blindly up to an ambiguity parameter utilizing the nature structure of STC,irrespective of the underlying signal constellations.Furthermore,a method was proposed to resolve the ambiguity by using a few pilot symbols.The simulation results show the proposed semi-blind estimator can achieve higher spectral efficiency and provide improved estimation performance compared to the non-blind estimator. 展开更多
关键词 channel estimation OFDM-STC SEMI-BLIND subspace-based
下载PDF
Exponential Stability Analysis of a Redundant Robot Configuration with a Built-in Safety System
5
作者 Xin Zhang 《Journal of Systems Science and Information》 2009年第4期289-293,共5页
The paper presents a model of a redundant robot configuration with a built-in safety. By the method of strong continuous semi-group, the paper analyzes the essential spectrum of the system operator before and after pe... The paper presents a model of a redundant robot configuration with a built-in safety. By the method of strong continuous semi-group, the paper analyzes the essential spectrum of the system operator before and after perturbation. The results show that in s special condition, the dynamic solution of the system is exponential stability and tends to the steady solution of the system. 展开更多
关键词 strictly dominant eigenvalue essential spectrum DISTURBANCE exponential stability
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部