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Existence of Al2F-7^- in molten MF–AlF3(M = K, Cs) systems as determined by Raman spectroscopy and structural simulation 被引量:5
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作者 Ming Lin Xianwei Hu +3 位作者 Zhongning Shi Bingliang Gao Jiangyu Yu Zhaowen Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第5期19-23,共5页
The molten mixtures of alkali metal fluorides and aluminum fluoride are applied as aluminum electrolytes or brazing fluxes.However,the presence of Al2F-7^-in such molten systems is disputed.In the present study,MF-AlF... The molten mixtures of alkali metal fluorides and aluminum fluoride are applied as aluminum electrolytes or brazing fluxes.However,the presence of Al2F-7^-in such molten systems is disputed.In the present study,MF-AlF3(M=K,Cs)systems with molar ratios<1 were studied by in-situ Raman spectroscopy and molecular simulation.The results show that,in addition to AlF6^(3-),AlF5^(2-),and AlF4^-,the systems also contained Al2F-7^-.The characteristic bands in the Raman spectra belonging to Al2F-7^-were located at about 225 cm^-1,315 cm^-1,479 cm^-1,and 720 cm^-1.There are two possible structures of Al2F-7^-,which belong to the D3d and D3hpoint groups.Both of these structures are linear,and their single-point energies were found to differ by only 0.31 kcal/mol. 展开更多
关键词 MF-AlF3(M=K Cs)systems Raman spectroscopy STRUCTURAL SIMULATION Al2F7^- Ionic structure
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Phase equilibria calculation of LaI_3-MI (M=Na,K,Cs) binary systems
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作者 王玉 邵国泉 +2 位作者 李少波 孙益民 乔芝郁 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第2期300-303,共4页
The Gibbs energies of liquid phases in the LaI3-MI (M= Na, K, Cs) systems were described by the modified quasi-chemical model. From the measured phase equilibrium data of these binary systems, a set of thermodynamic... The Gibbs energies of liquid phases in the LaI3-MI (M= Na, K, Cs) systems were described by the modified quasi-chemical model. From the measured phase equilibrium data of these binary systems, a set of thermodynamic functions were optimized by using the CAL- PHAD technique. The enthalpy of mixing and the interaction parameter of the liquid phase were predicted from known data for the LaI3-MI systems. 展开更多
关键词 phase equilibria LaI3-MI systems CALPHAD technique enthalpy of mixing rare earths
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Changing Rules of Bonding Electron Pair Correlation Energies of CH_3X (X=F,OH,NH_2) Systems
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作者 ZHUOShu-Ping SIWei-Jiang JUGuan-Zhi 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第5期525-531,共7页
The pair correlation energy of bonding electrons is used and analyzed in the cal- culation of CH and CY (Y = F, O, N) bonding electron pairs in CH3X (X = F, OH, NH2) isoelec- tronic systems based on intra- and interpa... The pair correlation energy of bonding electrons is used and analyzed in the cal- culation of CH and CY (Y = F, O, N) bonding electron pairs in CH3X (X = F, OH, NH2) isoelec- tronic systems based on intra- and interpair correlation energy results at both MP2-OPT2/6- 311++G(d) and MP2-OPT2/cc-pVtz levels with MELD program. Comparison of two set results shows that cc-pVtz and 6-311++G(d) give more correlation energy of valence electrons and innermost core electron pairs, respectively in these systems, resulting that the total correlation energy with cc-pVtz basis of each system is larger than that with 6-311++G(d). Investigations of pair correlation energy show that with the decrease of electronegativity of X atom and the increase of H atoms in these CH3X (X = F, OH, NH2) systems, the pair correlation energy of 1sC2 of the C atoms is transferable, and the correlation energy of CH bonding electron pair with little changes is of approximate transferability, while those of CY (CF, CO, CN) bonding electron pair decrease in a large extent from CH3F through CH3OH to CH3NH2 molecules. It is suggested that the study of pair correlation energy of bonding electrons will further deepen the understanding of electron corre- lation effect from traditional chemical bonding concept. 展开更多
关键词 pair correlation energy bonding electron pair CH3X systems
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Public key based uniform access framework in 3G systems
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作者 王弈 谷大武 白英彩 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2006年第4期404-408,共5页
This paper compares two types of access methods in 3G telecommunication systems, registration based access method and alternative access method. Through analyzing their common ground, we establish a public-key based u... This paper compares two types of access methods in 3G telecommunication systems, registration based access method and alternative access method. Through analyzing their common ground, we establish a public-key based uniform access framework, which combines different access methods into one unified model and provides more scalability and flexibility. Then an improved wireless authentication protocol is introduced into the framework, which gives an example of how unification is obtained by using public key technology. Since original protocol has flaws, an improved one is proposed based on security investigation. Improved authentication protocol overcomes the weakness of the original one, and maintains all the security features owned by old protocol. Finally, the feasibility of this framework is analyzed with consideration of current development in mobile telecommunication fields and the future trend of 3G systems. The result shows that public key technology has a promising future in 3G and Beyond 3G systems. It points out a new way for key management in future telecommunication systems. 展开更多
关键词 3G telecommunication systems public Key cryptosystem network access
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Research Framework of B3G Mobile Communications Systems
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作者 Chen Ming, You Xiaohu (National Mobile Communications Research Laboratory, Southeast University, Nanjing 210096, China) 《ZTE Communications》 2006年第2期29-34,共6页
Compared with the services in 3G, services in Beyond 3G (B3G) have some distinctive characteristics such as the packet data services being the majority, more service types, larger scale of services, higher peak transm... Compared with the services in 3G, services in Beyond 3G (B3G) have some distinctive characteristics such as the packet data services being the majority, more service types, larger scale of services, higher peak transmission rate, enlarged range of transmission rates, more spatial and temporal distribution differences, and more service transmission requests occurring in fast moving vehicles. In order to meet the requirements of B3G services, the B3G systems must have great improvement in network architecture, air interface scheme, radio resource allocation strategy, frequency bands, and Radio Frequency (RF) technology etc. Therefore, the research of the B3G systems should focus on the theory of generalized cellular communications networks, theory of the Multiple Input Multiple Output (MIMO) wireless transmission system, matching of radio resources to new-type air interfaces, new iterative detection and adaptive link methods, and new-type antenna and RF technologies. 展开更多
关键词 MIMO IEEE USA Research Framework of B3G Mobile Communications systems
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Thermodynamic optimization and calculation of phase diagrams of YbCl_3-MCl (M=Na, K, Rb, Cs) 被引量:1
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作者 孙益民 姚永香 +3 位作者 胡娟 孟祥珍 高天铱 乔芝郁 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第4期552-557,共6页
YbCl3-MCl (M = Na, K, Rb, Cs) systems were optimized and calculated using the CALPHAD (CALculation of PHAse Diagram) technique. The modified quasi-chemical model in the pair-approximation for short-range ordering ... YbCl3-MCl (M = Na, K, Rb, Cs) systems were optimized and calculated using the CALPHAD (CALculation of PHAse Diagram) technique. The modified quasi-chemical model in the pair-approximation for short-range ordering was used to describe the Gibbs energies of liquid phase in the systems. On the basis of the measured phase diagram data and experimental thermodynamic properties, a series of thermodynamic functions were optimized and calculated through an interactive computer-assisted analysis. Furthermore, some reasonable discussions on the thermodynamic parameters for these strong interaction binary systems were carded out. The results showed that the optimized parameters and experimental data are thermodynamically self-consistent. 展开更多
关键词 phase diagram YbCl3-MCl systems modified quasi-chemical model thermodynamic properties rare earths
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A Non-Singleton Type-3 Fuzzy Modeling: Optimized by Square-Root Cubature Kalman Filter 被引量:1
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作者 Aoqi Xu Khalid A.Alattas +3 位作者 Nasreen Kausar Ardashir Mohammadzadeh Ebru Ozbilge Tonguc Cagin 《Intelligent Automation & Soft Computing》 SCIE 2023年第7期17-32,共16页
In many problems,to analyze the process/metabolism behavior,a mod-el of the system is identified.The main gap is the weakness of current methods vs.noisy environments.The primary objective of this study is to present a... In many problems,to analyze the process/metabolism behavior,a mod-el of the system is identified.The main gap is the weakness of current methods vs.noisy environments.The primary objective of this study is to present a more robust method against uncertainties.This paper proposes a new deep learning scheme for modeling and identification applications.The suggested approach is based on non-singleton type-3 fuzzy logic systems(NT3-FLSs)that can support measurement errors and high-level uncertainties.Besides the rule optimization,the antecedent parameters and the level of secondary memberships are also adjusted by the suggested square root cubature Kalmanfilter(SCKF).In the learn-ing algorithm,the presented NT3-FLSs are deeply learned,and their nonlinear structure is preserved.The designed scheme is applied for modeling carbon cap-ture and sequestration problem using real-world data sets.Through various ana-lyses and comparisons,the better efficiency of the proposed fuzzy modeling scheme is verified.The main advantages of the suggested approach include better resistance against uncertainties,deep learning,and good convergence. 展开更多
关键词 MODELING computational intelligence fuzzy logic systems MODELING identification deep learning type-3 fuzzy systems optimization
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FTIR光谱、X射线和DTA法研究R_2O_3∶3Ga_2O_3∶4B_2O_3(R=La^(3+),Y^(3+),Yb^(3+))系的固态反应
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作者 E.Beregi 1, A.Watterich 1, J.Madarasz 2, J.Sztatisz 2,K.Polgar 1 (1.Research Institute for Solid State Physics and Optics,HAS,Po Box 49,H 1525 Budapest,Hungary 2.Institute of General and Analytical Chemistry,Technical University of Budapest,Szt.G 《人工晶体学报》 EI CAS CSCD 北大核心 2000年第S1期46-46,共1页
Single crystals of huntite type double borates possess excellent physical and chemical properties and are applied in laser optics.Substituted with various rare earths and Ga 3+ ,Cr 3+ or Sc 3+ ions the properties of t... Single crystals of huntite type double borates possess excellent physical and chemical properties and are applied in laser optics.Substituted with various rare earths and Ga 3+ ,Cr 3+ or Sc 3+ ions the properties of these borates can be improved. [1] For the first time double borates RGa 3(BO 3) 4(R=Y 3+ ,Sm 3+ ,Eu 3+ ,Gd 3+ ,Tb 3+ and Dy 3+ )were synthesised by Blasse and Bril [2] at 750℃. The goal of the present work is to study the solid state reactions in the R 2O 3∶3Ga 2O 3∶4B 2O 3(R=La 3+ ,Y 3+ ,Ho 3+ ,Yb 3+ )systems.Such reactions can lead to RGa 3(BO 3) 4 formation. Reagent grade oxide powders were used as reactants and mixed together in desired rations in acetone.Then differential thermal analysis(DTA)was used to study the formations of borates and changes in structure of mixtures heated up to 1000℃.In addition pellets were prepared by using 15mPa pressure and sintered at different temperatures from 600℃ to 1100℃ for 20 hours in order to study the reactions by IR and X ray. 展开更多
关键词 solid state reaction R 2O 33Ga 2O 3∶4B 2O 3(R=La 3+ Y 3+ Yb 3+ )systems
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3D (Three-Dimensional) Caco-2 Spheroids: Optimized in vitro Protocols to Favor Their Differentiation Process and to Analyze Their Cell Growth Behavior
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作者 Gabriella Rainaldi Alessandra Boe Sandra Gessani 《Journal of Pharmacy and Pharmacology》 2016年第7期341-350,共10页
3D (Three-dimensional) Caco-2 spheroids closely recapitulating in vivo physiological organization of intestinal epithelial cells, provide an excellent in vitro model system to study their pathophysiology and their r... 3D (Three-dimensional) Caco-2 spheroids closely recapitulating in vivo physiological organization of intestinal epithelial cells, provide an excellent in vitro model system to study their pathophysiology and their response to stressful stimuli. The objective of this technical note is to provide optimized in vitro experimental protocols for culturing 3D Caco-2 spheroids and for analyzing their cell growth features. An optimized 3D Caco-2 spheroid culturing technique based on a new configuration of the culture medium is provided A methodological approach to determine the distribution of the cell cycle phases in disaggregated Caco-2 spheroids by using cytofluorimetric analysis is also described. The optimized culturing protocol favors 3D Caco-2 spheroid differentiation process, as evaluated by the number of well-differentiated spheroids with a single hollow lumen. The cytofluorimetric analysis allows rapid collection of cell cycle phase data from high numbers of spheroid samples, thus, permitting to estimate their growth dynamics in a relatively short time. The optimized technical approaches described here can be applied in systematic manner to a variety of research activities utilizing 3D Caco-2 spheroids. Ease of use, time and economic saving advantages deriving from these protocols further highlight their potential. 展开更多
关键词 3D multicellular spheroids 3D intestinal epithelial spheroids 3D Caco-2 spheroid culture systems optimizedexperimental protocols.
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Dominant Correlation Effects in Two-Electron Atoms 被引量:1
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作者 Hubert Klar 《Journal of Applied Mathematics and Physics》 2020年第7期1424-1433,共10页
Two-electron atoms have been investigated near threshold of double escape within the framework of hyperspherical coordinates. A particularly useful set of hyperspherical angles has been used. It is well known for many... Two-electron atoms have been investigated near threshold of double escape within the framework of hyperspherical coordinates. A particularly useful set of hyperspherical angles has been used. It is well known for many years that the hyperradial motion is nearly separable from the hyperspherical angular motion. Therefore, the Born-Oppenheimer separation method should be useful. However, the success of that method in molecular physics is based on the small mass ratio, electron mass to nuclear mass. In the atomic application such a small parameter does not exist. Nevertheless the method works surprisingly well in the lower part of the spectrum. For increasing excitation energy the method becomes shaky. Near ionization threshold, it breaks even down. The author will present elsewhere an improved Born-Oppenheimer method. First pilot developments and comparison with the experimental situation are presented already here. Inclusion of a momentum-momentum radial coupling delivers an improved basis. We show that our extended Born-Oppenheimer approach leads to a deformation of the whole potential energy surface during the collision. In consequence of this deformation we outline a quantum derivation of the Wannier threshold cross section law, and we show that (e, 2e) angular distribution data are strongly influenced by that surface deformation. Finally, we present a mechanism for electron pair formation and decay leading to a supercurrent independent of the temperature. Our framework can be extended to more than two electrons, say 3 or 4. We conclude that our improved Born-Oppenheimer method <a href="#ref.1">[1]</a> is expected not only to deliver better numerical data, but it is expected to describe also the Wannier phenomenon. The idea of the new theory together with first qualitative results is presented in this paper. 展开更多
关键词 Born-Oppenheimer Approximation Wannier Theory Electronic Correlation 3-Body systems Hyperspherical Coordinates
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Bifurcation and Chaotic Dynamics of Homoclinic Systems in R^3 被引量:2
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作者 Sun Jianhua Department of Mathematics Nanjing University Nanjing, 210008 China 《Acta Mathematica Sinica,English Series》 SCIE CSCD 1995年第2期128-136,共9页
We consider perturbations which may or may not depend explicitly on time for the three-dimensional homoclinic systems. We obtain the existence and bifurcation theorems for transversal homoclinic points and homoclinic ... We consider perturbations which may or may not depend explicitly on time for the three-dimensional homoclinic systems. We obtain the existence and bifurcation theorems for transversal homoclinic points and homoclinic orbits, and illustrate our results with two examples. 展开更多
关键词 Bifurcation and Chaotic Dynamics of Homoclinic systems in R~3
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THE E^(1)_(3) TYPE OF CUBIC SYSTEMS WITH TWO INTEGRAL STRAIGHT LINES
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作者 陈国维 《Annals of Differential Equations》 1998年第1期13-23,共11页
The existence and uniqueness of limit cycle for the E 1 3 type of cubic systems with two integral straight lines has been studied in this paper. It is found that the system has no limit cycle when the two int... The existence and uniqueness of limit cycle for the E 1 3 type of cubic systems with two integral straight lines has been studied in this paper. It is found that the system has no limit cycle when the two integral straight lines intersect each other; it has a unique limit cycle when the two integral straight lines are paralleled. The sufficient and necessary conditions are also given to guarantee the existence of the unique limit cycle. 展开更多
关键词 E 1 3 type of cubic systems integral straight line limit cycle
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CALCULATION OF FOCAL VALUES FOR E_3~1 SYSTEMS
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作者 黄元石 刘蓉 《Annals of Differential Equations》 1999年第3期249-259,共11页
In this paper, we investigate the calculation method of focal values for E13systems. By means of Poincare method and Wu elimination, we design a special algorithm to calculate focal values for E13 systems and obtain s... In this paper, we investigate the calculation method of focal values for E13systems. By means of Poincare method and Wu elimination, we design a special algorithm to calculate focal values for E13 systems and obtain some satisfactory results on analysing the number of limit cycles for E13 systems. 展开更多
关键词 focal values limit cycles E_3~1 systems
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FOCAL QUANTITIES AND BIFURCATION OF LIMIT CYCLES FOR E^1_3 SYSTEM
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作者 黄元石 刘蓉 《Annals of Differential Equations》 1999年第4期362-377,共16页
In this paper, we discuss focal quantities and bifurcation of limit cycles forE^1_3 systems. By means of the algorithm designed in [l] and by computing, weanalyse completely the conditions for the origin being a cente... In this paper, we discuss focal quantities and bifurcation of limit cycles forE^1_3 systems. By means of the algorithm designed in [l] and by computing, weanalyse completely the conditions for the origin being a center and the orderof the origin being a fine focus in the both cases of B/0 and B= 0 for E^1_3systems. 展开更多
关键词 QUANTITIES limit cycles E^1_3 systems
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Novel plant activators with thieno[2,3-d]-1,2,3-thiadiazole-6-carboxylate scaffold: Synthesis and bioactivity 被引量:4
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作者 Qing-Shan Du Yan-Xia Shi +5 位作者 Peng-Fei Li Zhen-Jiang Zhao Wei-Ping Zhu Xu-Hong Qian Bao-Ju Li Yu-Fang Xu 《Chinese Chemical Letters》 SCIE CAS CSCD 2013年第11期967-969,共3页
The 1,2,3-thiadiazole-carboxylate moiety was reported to be an important pharmacophore of plant activators.In this study,a series of novel plant activators based on thieno[2,3-d]-1,2,3-thiadiazole-6-carboxylate were d... The 1,2,3-thiadiazole-carboxylate moiety was reported to be an important pharmacophore of plant activators.In this study,a series of novel plant activators based on thieno[2,3-d]-1,2,3-thiadiazole-6-carboxylate were designed and synthesized and their biological activity as plant activators was studied.The structures of the novel compounds were identifed by1H NMR,19F NMR and HRMS.The in vivo bioassay showed that these novel compounds had good effcacy against seven plant diseases.Especially,compounds 1a and 1c were more potent than the commercialized plant activator BTH.Almost no fungicidal activity was observed for the active compounds in the in vitro assay,which matched the requirements as plant activators. 展开更多
关键词 Thieno[2 3-d]-1 2 3-thiadiazole-6-carboxylate derivatives Plant activator Systemic acquired resistance
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Nonlinear effects in topological materials 被引量:1
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作者 Jack WZUBER Chao ZHANG 《Frontiers of Optoelectronics》 EI CSCD 2021年第1期99-109,共11页
Materials,where charge carriers have a linear energy dispersion,usually exhibit a strong nonlinear optical response in the absence of disorder scattering.This nonlinear response is particularly interesting in the tera... Materials,where charge carriers have a linear energy dispersion,usually exhibit a strong nonlinear optical response in the absence of disorder scattering.This nonlinear response is particularly interesting in the terahertz frequency region.We present a theoretical and numerical investigation of charge transport and nonlinear effects,such as the high harmonic generation in topological materials including Weyl semimetals(WSMs)and α-T_(3)systems.The nonlinear optical conductivity is calculated both semi-classically using the velocity operator and quantum mechanically using the density matrix.We show that the nonlinear response is strongly dependent on temperature and topological parameters,such as the Weyl point(WP)separation b and Berry phase ФB.A finite spectral gap opening can further modify the nonlinear effects.Under certain parameters,universal behaviors of both the linear and nonlinear response can be observed.Coupled with experimentally accessible critical field values of 10^(4)-10^(5) V=m,our results provide useful information on developing nonlinear optoelectronic devices based on topological materials. 展开更多
关键词 TERAHERTZ nonlinear effects topological materials Weyl semimetals(WSMs) α-T_(3) systems
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Pose Synchronization of Multiple Rigid Bodies Under Average Dwell Time Condition 被引量:1
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作者 DENG Juan WANG Lin +1 位作者 LIU Zhixin HU Xiaoming 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2018年第1期215-233,共19页
This paper considers the pose synchronization problem of a group of moving rigid bodies under switching topologies where the dwell time of each topology may has no nonzero lower bound. The authors introduce an average... This paper considers the pose synchronization problem of a group of moving rigid bodies under switching topologies where the dwell time of each topology may has no nonzero lower bound. The authors introduce an average dwell time condition to characterize the length of time intervals in which the graphs are connected. By designing distributed control laws of angular velocity and linear velocity,the closed-loop dynamics of multiple rigid bodies with switching topologies can be converted into a hybrid dynamical system. The authors employ the Lyapunov stability theorem, and show that the pose synchronization can be reached under the average dwell time condition. Moreover, the authors investigate the pose synchronization problem of the leader-following model under a similar average dwell time condition. Simulation examples are given to illustrate the results. 展开更多
关键词 Average dwell time hybrid dynamical systems pose synchronization rigid body SE(3
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