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期刊论文 85

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关键词

2

稳定性 2

CP);符号间干扰(inter symbol interference, ISI);载波间干扰(inter carrier interference 1

DPP);分布式功率转换器;开关电容转换器 1

ICI);最大似然估计(maximum likelihood estimation 1

MLE) 1

MPPT);差分功率处理(Differential power processing 1

OFDM);快速傅立叶变换(Fast Fourier transform, FFT);循环前缀(cyclic prefix 1

R/S分析 1

ε-不敏感损失函数 1

丙烯 1

中断模型;k-可靠性;对偶;线性规划松弛;互补松弛型 1

低合金高强度钢 1

例外点 1

倾转旋翼机;状态跟踪控制;线性切换系统;类时间依赖的多Lyapunov函数方法;光滑插值 1

全国火灾起数 1

共同李雅普诺夫函数 1

切换拓扑 1

判别学习;统计建模;贝叶斯分类器;高斯混合模型;UCI数据集 1

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Dynamic characteristics of an NC table with phase space reconstruction

Linhong WANG, Bo WU, Runsheng DU, Shuzi YANG

《机械工程前沿(英文)》 2009年 第4卷 第2期   页码 179-183 doi: 10.1007/s11465-009-0018-9

摘要: The dynamic properties of a numerical control (NC) table directly interfere with the accuracy and surface quality of work pieces machined by a computer numerical control (CNC) machine. Phase space reconstruction is an effective approach for researching dynamic behaviors of a system with measured time series. Based on the theory and method for phase space reconstruction, the correlation dimension, maximum Lyapunov exponent, and dynamic time series measured from the NC table were analyzed. The characteristic quantities such as the power spectrum, phase trajectories, correlation dimension, and maximum Lyapunov exponent are extracted from the measured time series. The chaotic characteristic of the dynamic properties of the NC table is revealed via various approaches. Therefore, an NC table is a nonlinear dynamic system. This research establishes a basis for dynamic system discrimination of a CNC machine.

关键词: NC table     chaotic characteristic     phase-space reconstruction     correlation dimension     maximum Lyapunov exponent    

Robust nonlinear control via feedback linearization and Lyapunov theory for permanent magnet synchronous

Ridha CHEIKH, Arezki MENACER, L. CHRIFI-ALAOUI, Said DRID

《能源前沿(英文)》 2020年 第14卷 第1期   页码 180-191 doi: 10.1007/s11708-018-0537-3

摘要: In this paper, the method for the nonlinear control design of a permanent magnet synchronous generator based-wind energy conversion system (WECS) is proposed in order to obtain robustness against disturbances and harvest a maximum power from a typical stochastic wind environment. The technique overcomes both the problem of nonlinearity and the uncertainty of the parameter compared to such classical control designs based on traditional control techniques. The method is based on the differential geometric feedback linearization technique (DGT) and the Lyapunov theory. The results obtained show the effectiveness and performance of the proposed approach.

关键词: permanent magnet synchronous generator     wind energy conversion system     stochastic     differential geometric     feedback linearization     maximum power point tracking     Lyapunov     robust control    

基于Lü系统的移动机器人完成特殊情况下全覆盖路径规划的参数值选择策略 Research Article

李彩虹1,刘聪1,宋勇2,梁振英1

《信息与电子工程前沿(英文)》 2023年 第24卷 第2期   页码 231-244 doi: 10.1631/FITEE.2200211

摘要: 针对移动机器人完成特殊情况下的全覆盖路径规划(complete coverage path planning, CCPP)任务,基于Lü系统,提出一种构造混沌机器人的系统参数值综合选择策略,以满足特殊任务下遍历轨迹高随机性和高覆盖率的需求。首先利用混沌系统必为耗散系统的特点,大致确定Lü系统成为耗散系统的参数取值范围;然后计算耗散系统下的李雅普诺夫指数谱,缩小系统参数的取值范围;其次画出这些参数下的相平面,大致判断其轨迹的拓扑分布特性;进一步在好的参数取值里,计算每个参数下变量的皮尔逊相关系数,判断每个变量的随机特性。最后,在所确定参数值下,利用其中的变量构造混沌机器人,并仿真测试了覆盖率,研究覆盖率和变量随机特性之间的关系。上述综合选择策略根据覆盖轨迹混沌性和随机性的要求,逐渐缩小了系统参数的取值范围。与使用一组固定的经典参数值的Lü系统相比,经过综合方法选择参数值的系统,能挑选出李雅普诺夫指数大的变量来构造混沌机器人,从而使覆盖轨迹的随机性能更高。另一个混沌Lorenz系统,用来测试和验证所设计策略的可行性和有效性。此类研究能够提高机器人完成特殊情况下CCPP任务的效率。

关键词: 混沌移动机器人;Lü系统;全覆盖路径规划;参数值选择策略;李雅普诺夫指数;皮尔逊相关系数    

Robust control based on the Lyapunov theory of a grid-connected doubly fed induction generator

Ridha CHEIKH, Arezki MENACER, Said DRID

《能源前沿(英文)》 2013年 第7卷 第2期   页码 191-196 doi: 10.1007/s11708-013-0245-y

摘要: This paper discusses the robust control of a grid-connected doubly-fed induction generator (DFIG) controlled by vector control using a nonlinear feedback linearization strategy in order to ameliorate the performances of the control and to govern the developed stator active and reactive power in a linear and decoupled manner, in which an optimal operation of the DFIG in sub-synchronous operation is given, as well as the control stator power flow with the possibility of keeping stator power factor at a unity. The use of the state-all-flux induction machine model gives place to a simpler control model. So, to achieve this objective, the Lyapunov approach is used associated with a sliding mode control to guarantee the global asymptotical stability and the robustness of the parametric variations.

关键词: doubly fed induction generator (DFIG)     vector control     Lyapunov function     power factor unity     active power     reactive power    

燃气轮机燃烧室效率模化试验中压力指数的研究

杨锐,王应时

《中国工程科学》 2003年 第5卷 第10期   页码 83-87

摘要:

通过对2种不同类型的燃气轮机燃烧室的数值计算,研究了不同燃烧类型对燃气轮机燃烧室效率模化试验中压力指数选取的影响。结果表明,压力指数除受到燃料、余气系数等影响之外,燃烧类型也有很大影响。对于以碳氢化合物为燃料,化学反应控制类型燃烧室模化中N值相对较大,大致范围为1.6~2.0。当燃烧过程受扩散控制时, N值相对较小,大致范围为1.0~1.4。

关键词: 燃烧室效率模化试验     压力指数     数值模拟    

Model reduction of contact dynamics simulation using a modified Lyapunov balancing method

Jianxun LIANG, Ou MA, Caishan LIU

《机械工程前沿(英文)》 2011年 第6卷 第4期   页码 383-391 doi: 10.1007/s11465-011-0244-9

摘要:

Finite element models are often used to simulate impact and contact dynamics responses of multibody dynamical systems. However, such a simulation remains very inefficient because very small integration time step must be used when solving the involved differential equations, especially when the involved contact stiffness is high. Although many model reduction techniques have been available to improve the efficiency of finite element based simulations, these techniques cannot be readily applied to contact dynamics simulations due to the high nonlinearity of the contact dynamics models. This paper presents a model reduction approach for finite-element based multibody contact dynamics simulation, based on a modified Lyapunov balanced truncation method. An example is presented to demonstrate that, by applying the model reduction the simulation process is significantly speeded up and the resulting error is bounded within an acceptable level. The performance of the method with respect to some influential factors such as element size, shape and contact stiffness is also investigated.

关键词: contact dynamics     dynamic simulation     model reduction     finite element method    

Robust direct power control based on the Lyapunov theory of a grid-connected brushless doubly fed induction

M. Abdelbasset MAHBOUB,Said DRID,M. A. SID,Ridha CHEIKH

《能源前沿(英文)》 2016年 第10卷 第3期   页码 298-307 doi: 10.1007/s11708-016-0411-0

摘要: This paper deals with robust direct power control of a grid-connected brushless doubly-fed induction generator(BDFIG). Using a nonlinear feedback linearization strategy, an attempt is made to improve the desired performances by controlling the generated stator active and reactive power in a linear and decoupled manner. Therefore, to achieve this objective, the Lyapunov approach is used associated with a sliding mode control to guarantee the global asymptotical stability. Thus, an optimal operation of the BDFIG in sub-synchronous operation is obtained as well as the stator power flows with the possibility of keeping stator power factor at a unity. The proposed method is tested with the Matlab/Simulink software. Simulation results illustrate the performances and the feasibility of the designed control.

关键词: brushless doubly fed induction generator (BDFIG)     vector control     Lyapunov theory     power factor unity     active and reactive power    

Principle of maximum entropy for reliability analysis in the design of machine components

Yimin ZHANG

《机械工程前沿(英文)》 2019年 第14卷 第1期   页码 21-32 doi: 10.1007/s11465-018-0512-z

摘要: We studied the reliability of machine components with parameters that follow an arbitrary statistical distribution using the principle of maximum entropy (PME). We used PME to select the statistical distribution that best fits the available information. We also established a probability density function (PDF) and a failure probability model for the parameters of mechanical components using the concept of entropy and the PME. We obtained the first four moments of the state function for reliability analysis and design. Furthermore, we attained an estimate of the PDF with the fewest human bias factors using the PME. This function was used to calculate the reliability of the machine components, including a connecting rod, a vehicle half-shaft, a front axle, a rear axle housing, and a leaf spring, which have parameters that typically follow a non-normal distribution. Simulations were conducted for comparison. This study provides a design methodology for the reliability of mechanical components for practical engineering projects.

关键词: machine components     reliability     arbitrary distribution parameter     principle of maximum entropy    

Fractional order extremum seeking approach for maximum power point tracking of photovoltaic panels

Ammar NEÇAIBIA,Samir LADACI,Abdelfatah CHAREF,Jean Jacques LOISEAU

《能源前沿(英文)》 2015年 第9卷 第1期   页码 43-53 doi: 10.1007/s11708-014-0343-5

摘要: Due to the high interest in renewable energy and diversity of research regarding photovoltaic (PV) array, a great research effort is focusing nowadays on solar power generation and its performance improvement under various weather conditions. In this paper, an integrated framework was proposed, which achieved both maximum power point tracking (MPPT) and minimum ripple signals. The proposed control scheme was based on extremum-seeking (ES) combined with fractional order systems (FOS). This auto-tuning strategy was developed to maximize the PV panel output power through the regulation of the voltage input to the DC/DC converter in order to lead the PV system steady-state to a stable oscillation behavior around the maximum power point (MPP). It is shown that fractional order operators can improve the plant dynamics with respect to time response and disturbance rejection. The effectiveness of the proposed controller scheme is illustrated with simulations using measured solar radiation data.

关键词: extremum seeking (ES)     fractional order control (FOC)     fractional calculus     photovoltaic (PV) panel     maximum power point tracking (MPPT)    

The combined effects of biomass and temperature on maximum specific ammonia oxidation rate in domestic

《环境科学与工程前沿(英文)》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1411-9

摘要:

• Actual SAORs was determined using MLVSS and temperature.

关键词: Specific ammonia oxidation rate     Sequencing batch reactor     Biomass     Temperature coefficient     Model simulation    

Topology optimization of transient problem with maximum dynamic response constraint using SOAR scheme

《机械工程前沿(英文)》 2021年 第16卷 第3期   页码 593-606 doi: 10.1007/s11465-021-0636-4

摘要: This paper proposes a novel method for the continuum topology optimization of transient vibration problem with maximum dynamic response constraint. An aggregated index in the form of an integral function is presented to cope with the maximum response constraint in the time domain. The density filter solid isotropic material with penalization method combined with threshold projection is developed. The sensitivities of the proposed index with respect to design variables are conducted. To reduce computational cost, the second-order Arnoldi reduction (SOAR) scheme is employed in transient analysis. Influences of aggregate parameter, duration of loading period, interval time, and number of basis vectors in the SOAR scheme on the final designs are discussed through typical examples while unambiguous configuration can be achieved. Through comparison with the corresponding static response from the final designs, the optimized results clearly demonstrate that the transient effects cannot be ignored in structural topology optimization.

关键词: topology optimization     solid isotropic material with penalization     transient response     aggregation function     second-order Arnoldi reduction    

Maximum entropy based finite element analysis of porous media

Emad NOROUZI, Hesam MOSLEMZADEH, Soheil MOHAMMADI

《结构与土木工程前沿(英文)》 2019年 第13卷 第2期   页码 364-379 doi: 10.1007/s11709-018-0470-x

摘要: The maximum entropy theory has been used in a wide variety of physical, mathematical and engineering applications in the past few years. However, its application in numerical methods, especially in developing new shape functions, has attracted much interest in recent years. These shape functions possess the potential for performing better than the conventional basis functions in problems with randomly generated coarse meshes. In this paper, the maximum entropy theory is adopted to spatially discretize the deformation variable of the governing coupled equations of porous media. This is in line with the well-known fact that higher-order shape functions can provide more stable solutions in porous problems. Some of the benchmark problems in deformable porous media are solved with the developed approach and the results are compared with available references.

关键词: maximum entropy FEM     fully coupled multi-phase system     porous media    

Overlap maximum matching ratio (OMMR): a new measure to evaluate overlaps of essential modules

Xiao-xia ZHANG,Qiang-hua XIAO,Bin LI,Sai HU,Hui-jun XIONG,Bi-hai ZHAO

《信息与电子工程前沿(英文)》 2015年 第16卷 第4期   页码 293-300 doi: 10.1631/FITEE.1400282

摘要: Protein complexes are the basic units of macro-molecular organizations and help us to understand the cell’s mechanism. The development of the yeast two-hybrid, tandem affinity purification, and mass spectrometry high-throughput proteomic techniques supplies a large amount of protein-protein interaction data, which make it possible to predict overlapping complexes through computational methods. Research shows that overlapping complexes can contribute to identifying essential proteins, which are necessary for the organism to survive and reproduce, and for life’s activities. Scholars pay more attention to the evaluation of protein complexes. However, few of them focus on predicted overlaps. In this paper, an evaluation criterion called overlap maximum matching ratio (OMMR) is proposed to analyze the similarity between the identified overlaps and the benchmark overlap modules. Comparison of essential proteins and gene ontology (GO) analysis are also used to assess the quality of overlaps. We perform a comprehensive comparison of serveral overlapping complexes prediction approaches, using three yeast protein-protein interaction (PPI) networks. We focus on the analysis of overlaps identified by these algorithms. Experimental results indicate the important of overlaps and reveal the relationship between overlaps and identification of essential proteins.

关键词: Protein-protein interaction network     Essential protein modules     Overlap     Overlap maximum matching ratio    

耗散陀螺系统的李雅普诺夫函数构造:剩余能量函数方法 Personal View

Cem CİVELEK, Özge CİHANBEĞENDİ

《信息与电子工程前沿(英文)》 2020年 第21卷 第4期   页码 629-634 doi: 10.1631/FITEE.1900014

摘要: 在自由度为4、张量有逆变(右上标)和协变(右下标)形式的耗散陀螺系统中,使用二阶线性微分方程建立拉格朗日耗散模型,即{L, D}模型。通过系统的{L, D}模型确定广义元素。满足勒让德变换先决条件时,可得哈密顿量。剩余能量函数(REF)由哈密顿量及损耗或耗散能量(为负)之和组成,将其作为李雅普诺夫函数,可通过李雅普诺夫第二方法作稳定性分析,并从数学上推导出稳定性条件。

关键词: 李雅普诺夫函数;剩余能量函数;耗散陀螺系统稳定性    

材料的一种新型应力应变模型

张于贤,王红

《中国工程科学》 2007年 第9卷 第8期   页码 88-91

摘要:

为研究自增强超高压容器的残余应力,提出了一个新型的应力应变模型,该模型比别的模型更接近于自增强超高压容器用钢的实际工作情况;以某材料为例介绍了确定该新型模型的方法,并对其误差进行了分析,论述了由一般的拉伸曲线求解该新型的应力应变关系模型的可行性及可靠性。

关键词: 低合金高强度钢     自增强     应力应变模型     硬化参数    

标题 作者 时间 类型 操作

Dynamic characteristics of an NC table with phase space reconstruction

Linhong WANG, Bo WU, Runsheng DU, Shuzi YANG

期刊论文

Robust nonlinear control via feedback linearization and Lyapunov theory for permanent magnet synchronous

Ridha CHEIKH, Arezki MENACER, L. CHRIFI-ALAOUI, Said DRID

期刊论文

基于Lü系统的移动机器人完成特殊情况下全覆盖路径规划的参数值选择策略

李彩虹1,刘聪1,宋勇2,梁振英1

期刊论文

Robust control based on the Lyapunov theory of a grid-connected doubly fed induction generator

Ridha CHEIKH, Arezki MENACER, Said DRID

期刊论文

燃气轮机燃烧室效率模化试验中压力指数的研究

杨锐,王应时

期刊论文

Model reduction of contact dynamics simulation using a modified Lyapunov balancing method

Jianxun LIANG, Ou MA, Caishan LIU

期刊论文

Robust direct power control based on the Lyapunov theory of a grid-connected brushless doubly fed induction

M. Abdelbasset MAHBOUB,Said DRID,M. A. SID,Ridha CHEIKH

期刊论文

Principle of maximum entropy for reliability analysis in the design of machine components

Yimin ZHANG

期刊论文

Fractional order extremum seeking approach for maximum power point tracking of photovoltaic panels

Ammar NEÇAIBIA,Samir LADACI,Abdelfatah CHAREF,Jean Jacques LOISEAU

期刊论文

The combined effects of biomass and temperature on maximum specific ammonia oxidation rate in domestic

期刊论文

Topology optimization of transient problem with maximum dynamic response constraint using SOAR scheme

期刊论文

Maximum entropy based finite element analysis of porous media

Emad NOROUZI, Hesam MOSLEMZADEH, Soheil MOHAMMADI

期刊论文

Overlap maximum matching ratio (OMMR): a new measure to evaluate overlaps of essential modules

Xiao-xia ZHANG,Qiang-hua XIAO,Bin LI,Sai HU,Hui-jun XIONG,Bi-hai ZHAO

期刊论文

耗散陀螺系统的李雅普诺夫函数构造:剩余能量函数方法

Cem CİVELEK, Özge CİHANBEĞENDİ

期刊论文

材料的一种新型应力应变模型

张于贤,王红

期刊论文