期刊文献+
共找到216,872篇文章
< 1 2 250 >
每页显示 20 50 100
Triangle Bounded L⁃algebras and Triangle Ideals
1
作者 Hao Chen Xiaolong Xin 《Journal of Harbin Institute of Technology(New Series)》 2025年第5期52-64,共13页
This study mainly focuses on the triangle bounded L⁃algebras and triangle ideals.Firstly,the definition of triangle bounded L⁃algebras is presented,and several examples with different conditions are outlined along wit... This study mainly focuses on the triangle bounded L⁃algebras and triangle ideals.Firstly,the definition of triangle bounded L⁃algebras is presented,and several examples with different conditions are outlined along with an exploration of their properties.Moreover,we investigate the structure of triangle bounded L⁃algebra with a special condition.Secondly,we define the concept of triangle ideals of triangle bounded L⁃algebra and explore the connection between the triangle ideals of triangle bounded L⁃algebra L and the ideals of bounded L⁃algebra E(L).In addition,we classified and studied various classes of triangle ideals,including Stonean triangle ideals,extended Stonean triangle ideals,and lattice ideals,and by introducing the notion of Stonean triangle bounded L algebras,we examine the relationship between Stonean triangle bounded L⁃algebras and Stonean triangle ideals.Finally,we investigate the interrelationships among these various types of triangle ideals. 展开更多
关键词 triangle bounded L⁃algebra Stonean triangle bounded L⁃algebra triangle ideal (extended)Stonean triangle ideal lattice ideal
在线阅读 下载PDF
Tunable Topological Floquet Bound States in the Continuum in a Periodically Driven Double SSH Chain
2
作者 Xian Duan Ruozhen Wang +3 位作者 Bo Zhu Zhi Tan Honghua Zhong Shu Chen 《Chinese Physics Letters》 2025年第9期77-87,共11页
We propose a novel approach to generate and manipulate topological Floquet bound states in the continuum(BICs)via a class of systems constructed by coupling two identical periodically driven one-dimensional Su-Schrief... We propose a novel approach to generate and manipulate topological Floquet bound states in the continuum(BICs)via a class of systems constructed by coupling two identical periodically driven one-dimensional Su-Schrieffer-Heeger chains.The formation of topological Floquet BICs can be adjusted only by tuning the driving amplitude or frequency,regardless of whether the static system has BICs or not.The interchain bias can only change the localization property of topological Floquet BICs,and a bigger bias can lead to transforming topological Floquet BICs into bound states out of the continuum(BOCs).But it does not change the topological properties of these topological Floquet states.Based on the repulsion effect of edge states,we propose to detect occurrence of topological Floquet BICs and transition point between topological Floquet BICs and BOCs using quantum walk.Our work provided a convenient and realistic approach for the experimental realization and manipulation of BICs in a single-particle quantum system. 展开更多
关键词 generate manipulate topological floquet bound states static system CONTINUUM double SSH chain class systems interchain bias floquet bicsand tunable topological floquet bound states
原文传递
Nowhere-zero 5-fows for graphs with bounded genus
3
作者 LI Jiaao SU Bo 《运筹学学报(中英文)》 北大核心 2025年第3期124-134,共11页
A nowhere-zero k-flow on a graph G=(V(G),E(G))is a pair(D,f),where D is an orientation on E(G)and f:E(G)→{±1,±2,,±(k-1)}is a function such that the total outflow equals to the total inflow at each vert... A nowhere-zero k-flow on a graph G=(V(G),E(G))is a pair(D,f),where D is an orientation on E(G)and f:E(G)→{±1,±2,,±(k-1)}is a function such that the total outflow equals to the total inflow at each vertex.This concept was introduced by Tutte as an extension of face colorings,and Tutte in 1954 conjectured that every bridgeless graph admits a nowhere-zero 5-flow,known as the 5-Flow Conjecture.This conjecture is verified for some graph classes and remains unresolved as of today.In this paper,we show that every bridgeless graph of Euler genus at most 20 admits a nowhere-zero 5-flow,which improves several known results. 展开更多
关键词 5-fow conjecture minimal counterexample graphs with bounded genus
在线阅读 下载PDF
Independent dual-band bound states in the continuum based on terahertz all-dielectric metasurfaces
4
作者 WANG Yu LIU Yang +5 位作者 HAO Xiao-yu ZHENG Si-yu LIU Meng ZHANG Yu-ping ZHAN Yi ZHANG Hui-yun 《中国光学(中英文)》 北大核心 2025年第5期1230-1242,共13页
Compared to traditional single-frequency bound states in the continuum(BIC),dual-band BIC of-fers higher degrees of freedom and functionality.Moveover,implementing independent control of dual-band BICs can further enh... Compared to traditional single-frequency bound states in the continuum(BIC),dual-band BIC of-fers higher degrees of freedom and functionality.Moveover,implementing independent control of dual-band BICs can further enhance their advantages and maximize their performance.This study presents a design for a dielectric metasurface that achieves dual-band BICs in the terahertz(THz)range.By adjusting two asym-metry parameters of the structure,independent control of the two symmetry-protected BICs is achieved.Fur-thermore,by varying the shape of the silicon holes,the design's robustness to geometric variations is demon-strated.Finally,the test results show that the figures of merit(FOMs)for both BICs reach 109.This work provides a new approach for realizing and tuning dual-frequency BICs,offering expanded possibilities for applications in multimode lasers,nonlinear optics,multi-channel filtering,and optical sensing. 展开更多
关键词 dual-band bound states in the continuum metasurface terahertz sensing symmetry protection
在线阅读 下载PDF
Attosecond Time Delay in Bound-Bound Transitions Probed by Fano Resonances
5
作者 Zhigang Zheng Li Wang +5 位作者 Di Wang Mingyue Wang Fan Xiao Jing Zhao Xiaowei Wang Zengxiu Zhao 《Chinese Physics Letters》 2025年第9期23-27,共5页
This letter presents a method for probing the attosecond time delay between two radiatively resonant transitions from Fano structures,which arise from interference between the extreme ultraviolet free induction decay(... This letter presents a method for probing the attosecond time delay between two radiatively resonant transitions from Fano structures,which arise from interference between the extreme ultraviolet free induction decay(XFID)emission and high-order harmonics.The ellipticity dependence of the Ne^(+)XFID yield confirms that the ionic excited-state populations originate from inelastic recollision between tunneling electrons and parent ions.Subsequent extraction of relative phases from Fano structures enables the determination of the time delay(~22 as)between the two decay pathways.This work provides an experimental approach to probe the attosecond time delay between different XFID channels and contributes to a deeper understanding of the tunneling-plusrescattering model in strong laser fields. 展开更多
关键词 radiatively resonant transitions extraction relative phases parent ionssubsequent fano structureswhich bound bound transitions tunneling electrons inelastic recollision fano structures
原文传递
Importance of the Breit Interaction for Electron-Positron Pair Production in Bound-Bound Muon Transitions
6
作者 Oleg Yu.Andreev Deyang Yu +1 位作者 Konstantin N.Lyashchenko Daria M.Vasileva 《Chinese Physics Letters》 2025年第9期18-22,共5页
We explored a distinct mechanism for matter creation via electron-positron pair production during bound-bound transitions in the deexcitation of muonic atoms.For ions with nuclear charges Z≥24,transitions from low-ly... We explored a distinct mechanism for matter creation via electron-positron pair production during bound-bound transitions in the deexcitation of muonic atoms.For ions with nuclear charges Z≥24,transitions from low-lying excited states to the 1s-muon state can lead to the production of electron-positron pairs.We show that the Breit interaction determines the transition probabilities for states with nonzero orbital momentum.We show that the pair production arises mainly from the decay of the 2p states.Thus,the Breit interaction governs electron-positron pair production in bound-bound muon transitions.This process offers a unique opportunity to explore quantum electrodynamics in strong fields,as well as a class of nonradiative transitions involving electron-positron pair production. 展开更多
关键词 breit interaction decay p statesthusthe muonic atomsfor Breit Interaction Electron Positron Pair Production Strong Fields bound bound Muon Transitions Quantum Electrodynamics
原文传递
New Universal Bounds for Eigenvalues of the Markov Diffusion Operator L2
7
作者 Yanli LI Feng DU 《Journal of Mathematical Research with Applications》 2025年第6期745-757,共13页
In this paper,we study the eigenvalue problem of the Markov diffusion operator L^(2),and give generalized inequalities for eigenvalues of the operator L^(2)on a Markov diffusion triple.By applying these inequalities,w... In this paper,we study the eigenvalue problem of the Markov diffusion operator L^(2),and give generalized inequalities for eigenvalues of the operator L^(2)on a Markov diffusion triple.By applying these inequalities,we then get some new universal bounds for eigenvalues of a special Markov diffusion operator L^(2)on bounded domains in an Euclidean space.Moreover,our results can reveal the relationship between the(k+1)-th eigenvalue and the first k eigenvalues in a relatively straightforward manner. 展开更多
关键词 Markov diffusion operator EIGENVALUES universal bounds Markov diffusion triple
原文传递
STARE:a new detector array for exploring the breakup reaction mechanisms induced by weakly bound nuclei
8
作者 Yan-Song Wu Gao-Long Zhang +12 位作者 Cheng-Jian Lin Nan-Ru Ma Lei Yang Guang-Xin Zhang Shi-Peng Hu Huan-Qiao Zhang Marco Mazzocco Yong-Jin Yao Zhen-Wei Jiao Ming-Li Wang Xue-Dou Su Hao-Bo Lv Kun Dong 《Nuclear Science and Techniques》 2025年第11期167-176,共10页
A new detector array with a large solid angle coverage for the coincidence measurement of charged fragments was developed to study the breakup reaction mechanisms of weakly bound nuclear systems at energies around the... A new detector array with a large solid angle coverage for the coincidence measurement of charged fragments was developed to study the breakup reaction mechanisms of weakly bound nuclear systems at energies around the Coulomb barrier.The array has been used to explore the breakup reaction mechanisms of^(6,7)Li+^(209)Bi systems at E_(beam)=30,40,47 MeV,showing good performance in particle identification and complete kinematic measurements.Based on this,different breakup modes and breakup components were clearly distinguished,and some new breakup modes were discovered,such as^(7)Li→α+t breakup mode in6Li+209Bi system and^(7)Li→^(6)He+p breakup mode in^(7)Li+^(209)Bi system.This array can also be used to explore other breakup reaction mechanisms induced by weakly bound nuclei. 展开更多
关键词 Detector array Coincidence measurement Breakup reaction Weakly bound nuclei
在线阅读 下载PDF
Upper bound stability analysis of tiered geosynthetic-reinforced soil wall
9
作者 Chengzhi Xiao Xiangsheng Meng +1 位作者 Shan Gao Luqiang Ding 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第1期556-572,共17页
The tiered geosynthetic-reinforced soil (GRS) walls have been increasingly applied in the high and steep retaining soil structures. However, very little is known about the design method for the tiered GRS wall in prac... The tiered geosynthetic-reinforced soil (GRS) walls have been increasingly applied in the high and steep retaining soil structures. However, very little is known about the design method for the tiered GRS wall in practice. This study is aimed at proposing an upper-bound stability analysis method of a tiered GRS wall. The proposed method was firstly validated by the existing results from the centrifuge test and the numerical method, and then a parametric study was performed to investigate the effects of the cohesionless backfill friction angle φ1 and the wall geometric parameters including the offset distance, the total wall height, the batter angle δ, the number of tiers n, and wall height ratio of adjacent tiers on the dimensionless equivalent earth pressure coefficient KT. The analysis results demonstrated that as the φ1 increases, the shear strength of backfill is enhanced and thus the KT or the total reinforcement tensile force decreases, and the KT decreases with the increase of the offset distance at the initial stage and then becomes stable when it reaches a certain critical value. For a fixed offset distance, the KT or the total reinforcement tensile force decreases with the increase of the δ. For the two-tiered GRS walls having the offset distance less than the critical value, the wall with the smaller wall height ratio has a larger KT. Further, the variation of the location of the critical failure surfaces of tiered GRS walls was presented in this study with the variation of the φ1 and the wall geometry. 展开更多
关键词 GEOSYNTHETICS Tiered GRS walls Offset distance Upper bound theorem Internal stability
在线阅读 下载PDF
Delay bounded routing with the maximum belief degree for dynamic uncertain networks
10
作者 MA Ji KANG Rui +3 位作者 LI Ruiying ZHANG Qingyuan LIU Liang WANG Xuewang 《Journal of Systems Engineering and Electronics》 2025年第1期127-138,共12页
Delay aware routing is now widely used to provide efficient network transmission. However, for newly developing or developed mobile communication networks(MCN), only limited delay data can be obtained. In such a netwo... Delay aware routing is now widely used to provide efficient network transmission. However, for newly developing or developed mobile communication networks(MCN), only limited delay data can be obtained. In such a network, the delay is with epistemic uncertainty, which makes the traditional routing scheme based on deterministic theory or probability theory not applicable. Motivated by this problem, the MCN with epistemic uncertainty is first summarized as a dynamic uncertain network based on uncertainty theory, which is widely applied to model epistemic uncertainties. Then by modeling the uncertain end-toend delay, a new delay bounded routing scheme is proposed to find the path with the maximum belief degree that satisfies the delay threshold for the dynamic uncertain network. Finally, a lowEarth-orbit satellite communication network(LEO-SCN) is used as a case to verify the effectiveness of our routing scheme. It is first modeled as a dynamic uncertain network, and then the delay bounded paths with the maximum belief degree are computed and compared under different delay thresholds. 展开更多
关键词 dynamic uncertain network uncertainty theory epistemic uncertainty delay bounded routing maximum belief degree
在线阅读 下载PDF
AN EXPONENTIAL NON-UNIFORM BERRY-ESSEEN BOUND OF SOME TIME INHOMOGENEOUS DIFFUSION PROCESS
11
作者 Qiaojing LIU Yaqian LV Baobin WANG 《Acta Mathematica Scientia》 2025年第5期1879-1890,共12页
this paper,we study the exponential non-uniform Berry-Esseen bound for the maximum likelihood estimator of some time inhomogeneous diffusion process.As applications,the optimal uniform Berry-Esseen bound and optimal C... this paper,we study the exponential non-uniform Berry-Esseen bound for the maximum likelihood estimator of some time inhomogeneous diffusion process.As applications,the optimal uniform Berry-Esseen bound and optimal Cramer-type moderate deviations of the Ornstein-Uhlenbeck process andα-Brownian bridge can be obtained.The main methods are the change of measure method and asymptotic analysis technique. 展开更多
关键词 Berry-Esseen bound time inhomogeneous diffusion process Cramer-type mod-erate deviations Ornstein-Uhlenbeck process
在线阅读 下载PDF
LOWER BOUNDS ESTIMATE FOR THE BLOW-UP TIME OF A NONLINEAR NONLOCAL POROUS MEDIUM EQUATION 被引量:20
12
作者 刘灯明 穆春来 辛巧 《Acta Mathematica Scientia》 SCIE CSCD 2012年第3期1206-1212,共7页
The lower bounds for the blow-up time of blow-up solutions to the nonlinear nolocal porous equation ut=△u^m+u^p∫Ωu^qdxwith either null Dirichlet boundary condition or homogeneous Neumann boundary condi- tion is g... The lower bounds for the blow-up time of blow-up solutions to the nonlinear nolocal porous equation ut=△u^m+u^p∫Ωu^qdxwith either null Dirichlet boundary condition or homogeneous Neumann boundary condi- tion is given in this article by using a differential inequality technique. 展开更多
关键词 Lower bounds blow-up time Dirichlet boundary condition Neumann boundary condition
在线阅读 下载PDF
Green’s Functions of a Class of Sturm-Liouville Problems with Eigenparameters in Boundary Conditions
13
作者 XIAO Lu MU Dan ZHANG Ruifan 《数学理论与应用》 2025年第1期94-106,共13页
In this paper,we study a class of Sturm-Liouville problems,where the boundary conditions involve eigenparameters.Firstly,by defining a new inner product which depends on the transmission conditions,we obtain a new Hil... In this paper,we study a class of Sturm-Liouville problems,where the boundary conditions involve eigenparameters.Firstly,by defining a new inner product which depends on the transmission conditions,we obtain a new Hilbert space,on which the concerned operator A is self-adjoint.Then we construct the fundamental solutions to the problem,obtain the necessary and sufficient conditions for eigenvalues,and prove that the eigenvalues are simple.Finally,we investigate Green’s functions of such problem. 展开更多
关键词 Sturm-Liouville problem Eigenparameter-dependent boundary condition Green’s function
在线阅读 下载PDF
随机级数的a.s.S-可和性与a.s.收敛性 被引量:2
14
作者 杨薇娜 《湖北大学学报(自然科学版)》 CAS 北大核心 2006年第1期7-11,共5页
通常在随机向量对称性条件下,人们研究随机级数a.s.S-可和性与a.s.收敛性的关系及a.s.S-有界性与a.s.有界性间的联系.对有关a.s.S-可和及a.s.有界的重要引理和定理进行了改进和推广,得到了进一步的结果.
关键词 S-可和 a.s.收敛 S-有界 a.s.有界
在线阅读 下载PDF
The decoherence of the triangular and Coulomb bound potential quantum dot qubit 被引量:2
15
作者 李红娟 孙家奎 肖景林 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第1期100-103,共4页
We study the eigenenergies and eigenfunctions of the ground and first-excited states of an electron which is strongly coupled to an LO-phonon in a quantum dot with a triangular bound potential and Coulomb bound potent... We study the eigenenergies and eigenfunctions of the ground and first-excited states of an electron which is strongly coupled to an LO-phonon in a quantum dot with a triangular bound potential and Coulomb bound potential by using the Pekar variational method. This system may be used as a two-level qnbit. Phonon spontaneous emission causes the decoherence of the qubit. Numerical calculations are performed on the decoherence rate as a function of the polar angle, the Coulomb binding parameter, the coupling strength, the confinement length of the quantum dot and the dispersion coefficient. 展开更多
关键词 quantum dot triangular bound potential Coulomb bound potential DECOHERENCE
原文传递
End-to-End Deterministic Transmission with Bounded Time Error in Time-Sensitive Networking
16
作者 Ma Hao Shou Guochu +3 位作者 Li Hongxing Liu Yaqiong Hu Yihong Chen Li 《China Communications》 2025年第12期30-46,共17页
Time synchronization is a prerequisite for ensuring determinism in time-sensitive networking(TSN).While time synchronization errors cannot be overlooked,pursuing minimal time errors may incur unnecessary costs.Using c... Time synchronization is a prerequisite for ensuring determinism in time-sensitive networking(TSN).While time synchronization errors cannot be overlooked,pursuing minimal time errors may incur unnecessary costs.Using complex network theory,this study proposes a hierarchy for TSN and introduces the concept of bounded time error.A coupling model between traffic scheduling and time synchronization is established,deriving functional relationships among end-to-end delay,delay jitter,gate window,and time error.These relationships illustrate that time errors can trigger jumps in delay and delay jitter.To evaluate different time errors impact on traffic scheduling performance,an end-to-end transmission experiment scheme is designed,along with the construction of a TSN test platform implementing two representative cases.Case A is a closed TSN domain scenario with pure TSN switches emulating closed factory floor network.Case B depicts remote factory interconnection where TSN domains link via non-TSN domains composed of OpenFlow switches.Results from Case A show that delay and delay jitter on a single node are most significantly affected by time errors,up to one gating cycle.End-to-end delay jitter tends to increase with the number of hops.When the ratio of time error bound to window exceeds 10%,the number of schedulable traffic flows decreases rapidly.Case B reveals that when time error is below 1μs,the number of schedulable traffic flows begins to increase significantly,approaching full schedulability at errors below 0.6μs. 展开更多
关键词 bounded time error deterministic communications time synchronization time-sensitive networking traffic scheduling
在线阅读 下载PDF
Release profile and metabolism of bound polyphenols of oat bran during in vitro simulated gastrointestinal digestion and colonic fermentation
17
作者 Yu Zhang Bing Bai +3 位作者 Kai Huang Sen Li Hongwei Cao Xiao Guan 《Food Science and Human Wellness》 2025年第4期1557-1565,共9页
Whole-grain foods have attracted emerging attention due to their health benefits.Whole grains are rich in bound polyphenols(BPs)linked with dietary fibers,which is largely underestimated compared with free polyphenols... Whole-grain foods have attracted emerging attention due to their health benefits.Whole grains are rich in bound polyphenols(BPs)linked with dietary fibers,which is largely underestimated compared with free polyphenols.In this study,in vitro simulated gastrointestinal digestion and colonic fermentation models were used to study the release profile and metabolism of BPs of oat bran.Significantly higher level of BPs was released during in vitro colon fermentation(3.05 mg GAE/g)than in gastrointestinal digestion(0.54 mg GAE/g).Five polyphenols were detected via LC-MS and their possible conversion pathways were speculated.Released BPs exhibited chemical antioxidant capacity.16S rRNA sequencing further revealed that Clostridium butyricum,Enterococcus faecalis,Bacteroides acidifaciens were the key bacteria involved in the release of BPs,and this was verified by whole-cell transformation.Our results helped to explain the possible mechanism of the health benefits of BPs in whole grains. 展开更多
关键词 Oat bran bound polyphenols In vitro digestion Colonic fermentation Ferulic acid
在线阅读 下载PDF
科学与信仰的冲突与调和——A.S.拜厄特“新维多利亚小说”中科学与信仰之谜题 被引量:1
18
作者 汤黎 李跃平 《四川师范大学学报(社会科学版)》 CSSCI 北大核心 2017年第4期113-119,共7页
当代英国女作家A.S.拜厄特"新维多利亚小说"通过对维多利亚时代科学观念和信仰危机的重述,从科学与信仰、物质与精神、灵魂与肉身这几个方面剖析了维多利亚人的困惑与希冀。小说反映了进化论和唯灵论这两大维多利亚思潮的冲突... 当代英国女作家A.S.拜厄特"新维多利亚小说"通过对维多利亚时代科学观念和信仰危机的重述,从科学与信仰、物质与精神、灵魂与肉身这几个方面剖析了维多利亚人的困惑与希冀。小说反映了进化论和唯灵论这两大维多利亚思潮的冲突,也再现了维多利亚人试图调和科学和信仰这两者所作出的尝试。唯灵论的流行揭示了维多利亚时期占主导地位的功利主义和实证主义面具之下的唯心主义和直觉主义倾向。作为维多利亚时期流行的科学主义和传统的宗教信仰之间的一种折衷方式,通灵术盛行的背后是对物质和精神之间关系的探寻,也是对灵魂与肉身关系的追问。维多利亚人对人类主体性的思索,对揭示世界本质的渴望,都可以在拜厄特的"新维多利亚小说"中得以窥见。 展开更多
关键词 a.s.拜厄特 “新维多利亚小说” 科学 信仰 唯灵论
在线阅读 下载PDF
Lower bound on BER performance for maximal ratio combining with weighting errors 被引量:1
19
作者 盛彬 尤肖虎 《Journal of Southeast University(English Edition)》 EI CAS 2005年第4期379-384,共6页
The theoretical lower bounds on mean squared channel estimation errors for typical fading channels are presented by the infinite-length and non-causal Wiener filter and the exact closed-form expressions of the lower b... The theoretical lower bounds on mean squared channel estimation errors for typical fading channels are presented by the infinite-length and non-causal Wiener filter and the exact closed-form expressions of the lower bounds for different channel Doppler spectra are derived. Based on the obtained lower bounds on mean squared channel estimation errors, the limits on bit error rate (BER) for maximal ratio combining (MRC) with Gaussian distributed weighting errors on independent and identically distributed (i. i. d) fading channels are presented. Numerical results show that the BER performances of ideal MRC are the lower bounds on the BER performances of non-ideal MRC and deteriorate as the maximum Doppler frequency increases or the SNR of channel estimate decreases. 展开更多
关键词 lower bound bit error rate minimum mean-square error channel estimation maximal ratio combining
在线阅读 下载PDF
Self-scheduled direct thrust control for gas turbine engine based on EME approach with bounded parameter variation
20
作者 Kehuan WANG Xiaofeng LIU Genchang WANG 《Chinese Journal of Aeronautics》 2025年第6期414-426,共13页
Direct Thrust Control(DTC) is effective in dealing with the mismatch between thrust and rotor speed in traditional engine control. Among the DTC architecture, model-based thrust estimation method has less arithmetic c... Direct Thrust Control(DTC) is effective in dealing with the mismatch between thrust and rotor speed in traditional engine control. Among the DTC architecture, model-based thrust estimation method has less arithmetic consumption and better real-time performance. In this paper,a direct thrust controller design approach for gas turbine engine based on parameter dependent model is proposed. In order to ensure the stability of DTC control system based on parameter dependent model, there are usually conservatism detects. For the purpose of reducing the conservatism in the solution process of filter and controller, an Equilibrium Manifold Expansion(EME) model with bounded parameter variation of engine is established. The design conditions of Kalman filter for discrete-time EME system are introduced, and the proposed conditions have a certain suppression effect on the input noise of the system with bounded parameter variation.The engine thrust estimator stability and H∞filtering problems are solved by the polytopic quadratic Lyapunov function based on the Linear Matrix Inequalities(LMIs). To meet the performance requirements of thrust control, the Grey Wolf Optimization(GWO) algorithm is applied to optimize the PID control parameters. The proposed method is verified on a Hardware-in-Loop(HIL) platform. The simulation results demonstrate that the DTC framework can ensure the stability of engine closed-loop system in large range deviation tests. The filter and controller solution method considering the parameter variation boundary can obtain a solution that makes the system have better performance parameters. Moreover, the proposed filter has better thrust estimation performance than the traditional Kalman filter under the condition of sensor noise. Compared with Augmented Linear Quadratic Regulator(ALQR) controller, the PID controller optimized by GWO has a faster response in simulation. 展开更多
关键词 Gas turbines Direct thrust control bounded parameter variation Linear matrix inequalities Greywolf optimization
原文传递
上一页 1 2 250 下一页 到第
使用帮助 返回顶部