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Criteria Condition for Generalized Diagonally Dominant Matrices 被引量:3
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作者 田素霞 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第1期102-106,共5页
In this paper, we provide some new necessary and sufficient conditions for generalized diagonally dominant matrices and also obtain some criteria for nongeneralized dominant matrices.
关键词 generalized diagonally dominant matrices Positive diagonal matrix criteria condition
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PARALLEL REGION PRESERVING MULTISECTION METHOD FOR SOLVING GENERALIZED EIGENPROBLEM 被引量:1
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作者 曾岚 周树荃 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1996年第2期51+46-50,共6页
The parallel multisection method for solving algebraic eigenproblem has been presented in recent years with the development of the parallel computers, but all the research work is limited in standard eigenproblems of ... The parallel multisection method for solving algebraic eigenproblem has been presented in recent years with the development of the parallel computers, but all the research work is limited in standard eigenproblems of symmetric tridiagonal matrix. The multisection method for solving the generalized eigenproblem applied significantly in many science and engineering domains has not been studied. The parallel region preserving multisection method (PRM for short) for solving generalized eigenproblems of large sparse and real symmetric matrix is presented in this paper. This method not only retains the advantages of the conventional determinant search method (DS for short), but also overcomes its disadvantages such as leaking roots and disconvergence. We have tested the method on the YH 1 vector computer, and compared it with the parallel region preserving determinant search method the parallel region preserving bisection method (PRB for short). The numerical results show that PRM has a higher speed up, for instance, it attains the speed up of 7.7 when the scale of the problem is 2 114 and the eigenpair found is 3, and PRM is superior to PRB when the scale of the problem is large. 展开更多
关键词 parallel processing structural analysis numerical algebra generalized eigenproblem parallel multisection method
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UNSTEADY FLOWS OF A GENERALIZED SECOND GRADE FLUID WITH THE FRACTIONAL DERIVATIVE MODEL BETWEEN TWO PARALLEL PLATES 被引量:19
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作者 谭文长 徐明喻 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2004年第5期471-476,共6页
The fractional calculus approach in the constitutive relationship model of a generalized second grade fluid is introduced.Exact analytical solutions are obtained for a class of unsteady flows for the generalized secon... The fractional calculus approach in the constitutive relationship model of a generalized second grade fluid is introduced.Exact analytical solutions are obtained for a class of unsteady flows for the generalized second grade fluid with the fractional derivative model between two parallel plates by using the Laplace transform and Fourier transform for fractional calculus.The unsteady flows are generated by the impulsive motion or periodic oscillation of one of the plates.In addition,the solutions of the shear stresses at the plates are also determined. 展开更多
关键词 fractional derivative unsteady flows generalized second grade fluid parallel plates
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The Generalized Roper-Suffridge Extension Operator for Locally Biholomorphic Mappings 被引量:48
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作者 LIU Xiao-song,LIU Tai-shun (Department of Mathematics, University of Science and Technology of C hina, Hefei 230026, China) 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第3期221-229,共9页
In this paper, we introduce the generalized R oper-Suffridge extension operator for locally biholomorphic mappings. It is sh own that this operator preserves the starlikeness on some Reinhardt domains and does not pre... In this paper, we introduce the generalized R oper-Suffridge extension operator for locally biholomorphic mappings. It is sh own that this operator preserves the starlikeness on some Reinhardt domains and does not preserve convexity for some cases. Meanwhile, the growth theorem and di stortion theorem of the corresponding mappings are given. 展开更多
关键词 biholomorphic mappings starlike mappings and convex mappings the generalized Roper-Suffridge extension operator
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3D Profile Filter Algorithm Based on Parallel Generalized B-spline Approximating Gaussian 被引量:3
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作者 REN Zhiying GAO Chenghui SHEN Ding 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第1期148-154,共7页
Currently, the approximation methods of the Gaussian filter by some other spline filters have been developed. However, thesc methods are only suitable for the study of one-dimensional filtering, when these methods are... Currently, the approximation methods of the Gaussian filter by some other spline filters have been developed. However, thesc methods are only suitable for the study of one-dimensional filtering, when these methods are used for three-dimensional filtering, it is found that a rounding error and quantization error would be passed to the next in every part. In this paper, a new and high-precision implementation approach for Gaussian filter is described, which is suitable for three-dimensional reference filtering. Based on the theory of generalized B-spline function and the variational principle, the transmission characteristics of a digital filter can be changed through the sensitivity of the parameters (t1, t2), and which can also reduce the rounding error and quantization error by the filter in a parallel form instead of the cascade form, Finally, the approximation filter of Gaussian filter is obtained. In order to verify the feasibility of the new algorithm, the reference extraction of the conventional methods are also used and compared. The experiments are conducted on the measured optical surface, and the results show that the total calculation by the new algorithm only requires 0.07 s for 480×480 data points; the amplitude deviation between the reference of the parallel form filter and the Gaussian filter is smaller; the new method is closer to the characteristic of the Gaussian filter through the analysis of three-dimensional roughness parameters, comparing with the cascade generalized B-spline approximating Gaussian. So the new algorithm is also efficient and accurate for the implementation of Gaussian filter in the application of surface roughness measurement. 展开更多
关键词 generalized B-spline Gaussian filter three-dimensional reference cascade characteristic parallel characteristic
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Dynamic stiffness method for free vibration of an axially moving beam with generalized boundary conditions 被引量:3
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作者 Hu DING Minhui ZHU Liqun CHEN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2019年第7期911-924,共14页
Axially moving beams are often discussed with several classic boundary conditions, such as simply-supported ends, fixed ends, and free ends. Here, axially moving beams with generalized boundary conditions are discusse... Axially moving beams are often discussed with several classic boundary conditions, such as simply-supported ends, fixed ends, and free ends. Here, axially moving beams with generalized boundary conditions are discussed for the first time. The beam is supported by torsional springs and vertical springs at both ends. By modifying the stiffness of the springs, generalized boundaries can replace those classical boundaries. Dynamic stiffness matrices are, respectively, established for axially moving Timoshenko beams and Euler-Bernoulli (EB) beams with generalized boundaries. In order to verify the applicability of the EB model, the natural frequencies of the axially moving Timoshenko beam and EB beam are compared. Furthermore, the effects of constrained spring stiffness on the vibration frequencies of the axially moving beam are studied. Interestingly, it can be found that the critical speed of the axially moving beam does not change with the vertical spring stiffness. In addition, both the moving speed and elastic boundaries make the Timoshenko beam theory more needed. The validity of the dynamic stiffness method is demonstrated by using numerical simulation. 展开更多
关键词 AXIallY moving BEAM natural frequency TIMOSHENKO BEAM model DYNAMIC stiffness matrix generalized boundary condition
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APPLICATION OF GENERALIZED CONVECTIVE VORTICITY VECTOR IN A RAINFALL PROCESS CAUSED BY A LANDFALLING TROPICAL DEPRESSION 被引量:4
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作者 喻自凤 余晖 《Journal of Tropical Meteorology》 SCIE 2012年第4期422-435,共14页
A heavy rainfall process, which occurred in Shanghai during 5-6 August, 2001 from a landfalling tropical depression (TD),is examined with a control numerical experiment based on MM5 model. It is found that the contour... A heavy rainfall process, which occurred in Shanghai during 5-6 August, 2001 from a landfalling tropical depression (TD),is examined with a control numerical experiment based on MM5 model. It is found that the contours of generalized equivalent potential temperature (θ*) are almost vertical with respect to horizontal surfaces near the TD center and more densely distributed than those of equivalent potential temperature (θe).Because the atmosphere is non-uniformly saturated in reality, θ* takes the place of θe in the definition of convective vorticity vector (CVV) so that a new vector, namely the generalized convective vorticity vector (CVV*), is applied in this study. Since CVV* can reflect both the secondary circulation and the variation of horizontal moist baroclinicity, the vertical integration of vertical component of CVV* is found, in this study, to represent the rainfall areas in the TD case better than potential vorticity (PV), moist potential vorticity (MPV), generalized moist potential vorticity (Pm), and CVV, with high-value area of CVV* corresponding to heavy-rainfall area. Moreover, the analysis from CVV* implies that the Hangzhou Bay might play an important role in the heavy rain process. A sensitivity experiment without the Hangzhou Bay is then designed and compared with the control run. It is found that the CVV* becomes weaker than that in the control run, implying that the elimination of Hangzhou Bay results in reduced rainfall. Further analyses show that the Hangzhou Bay provides sufficient water vapor and surface heat flux to the TD system, which is very important to the genesis and development of mesoscale cloud clusters around the TD and the associated heavy rainfall. 展开更多
关键词 tropical cyclone generalized convective vorticity vector (CVV*) RAINFall LANDFall
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Generalized Parallel Coprime Array for Two-Dimensional DOA Estimation:A Perspective from Maximizing Degree of Freedom 被引量:4
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作者 Luo Chen Xinping Lin +1 位作者 Beizuo Zhu Xiaofei Zhang 《China Communications》 SCIE CSCD 2021年第4期14-26,共13页
Parallel arrays with coprime subarrays have shown its potential advantages for two dimensional direction of arrival(DOA)estimation.In this paper,by introducing two flexible coprime factors to enlarge the inter-element... Parallel arrays with coprime subarrays have shown its potential advantages for two dimensional direction of arrival(DOA)estimation.In this paper,by introducing two flexible coprime factors to enlarge the inter-element spacing of parallel uniform subarrays,we propose a generalized parallel coprime array(GPCA)geometry.The proposed geometry enjoys flexible array layouts by the coprime factors and enables to extend the array aperture to achieve great improvement of estimation performance.Meanwhile,we verify that GPCA always can obtain M2 degrees of freedom(DOFs)in co-array domain via 2M sensors after optimization,which outperforms sparse parallel array geometries,such as parallel coprime array(PCA)and parallel augmented coprime array(PACA),and is the same as parallel nested array(PNA)with extended aperture.The superiority of GPCA geometry has been proved by numerical simulations with sparse representation methods. 展开更多
关键词 direction of arrival estimation generalized parallel coprime array degrees of freedom array aperture coprime factors
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Inference for dependence competing risks from bivariate exponential model under generalized progressive hybrid censoring with partially observed failure causes 被引量:2
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作者 WANG Liang LI Huanyu MA Jin'ge 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第1期201-208,共8页
Inference are considered for the dependence competing risks model by using the Marshal-Olkin bivariate exponential distribution. Under generalized progressively hybrid censoring with partially observed failure causes,... Inference are considered for the dependence competing risks model by using the Marshal-Olkin bivariate exponential distribution. Under generalized progressively hybrid censoring with partially observed failure causes, the maximum likelihood estimators are established, and the approximate confidence intervals are also constructed via the observed Fisher information matrix.Moreover, Bayes estimates and highest probability density credible intervals are presented and the importance sampling technique is used to compute corresponding results. Finally, the numerical analysis is proposed for illustration. 展开更多
关键词 DEPENDENCE competing risk generalized PROGRESSIVE HYBRID CENSORING BIVARIATE exponential distribution Bayesian inference.
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Criteria Conditions for Generalized Diagonally Dominant Matrices 被引量:3
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作者 TIAN Su-xia 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第1期63-67,共5页
In this paper, some new sufficient conditions for generalized dominant matrices are given, and some results in [1] are generalized and improved.
关键词 generalized diagonal dominant matrices α-diagonal dominant matrix criteria condition
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APPROXIMATION OF GENERALIZED BI-AXIALLY SYMMETRIC POTENTIALS WITH FAST RATES OF GROWTH 被引量:3
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作者 H.S.Kasana(Dept.of Math., Birla Iust.of Tech. & Sci.,Pilani-333 031(Rajasthan), India.D.Kumar)(Dept.of Math., D. S. M.Degree College, Kanth-244 501 (Moradabad),U.P.,India.) 《Acta Mathematica Scientia》 SCIE CSCD 1995年第4期458-467,共10页
The paper deals with growth and approximation of solutions (not necessarily entire) of certain elliptic partial differential equations. These solutions are called Generalized Bi-axially Symmetric Potentials (GBSP'... The paper deals with growth and approximation of solutions (not necessarily entire) of certain elliptic partial differential equations. These solutions are called Generalized Bi-axially Symmetric Potentials (GBSP's). The GBSP's are taken to be regular in a finite hyperball and influence of the growth of their maximum moduli on the rate of decay of their approximation errors in sup norm is studied. The authors obtain the characterizations of the q-type and lower q-type of a GBSP H ∈ HP,0 < R < ∞, in terms of rate of decay of approximation error E.(H,R0), 0 < R0<R <∞. 展开更多
关键词 generalized bi-axially symmetric potentials Elliptic partial differential equations Index q Entire GBSP polynomials Sup norm.
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Generalized thermoelastic functionally graded spherically isotropic solid containing a spherical cavity under thermal shock 被引量:2
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作者 M.K.Ghosh M.Kanoria 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第10期1263-1278,共16页
This paper is concerned with the determination of thermoelastic displacement, stress and temperature in a functionally graded spherically isotropic infinite elastic medium having a spherical cavity, in the context of ... This paper is concerned with the determination of thermoelastic displacement, stress and temperature in a functionally graded spherically isotropic infinite elastic medium having a spherical cavity, in the context of the linear theory of generalized thermoelasticity with two relaxation time parameters (Green and Lindsay theory). The surface of cavity is stress-free and is subjected to a time-dependent thermal shock. The basic equations have been written in the form of a vector-matrix differential equation in the Laplace transform domain, which is then solved by an eigenvalue approach. Numerical inversion of the transforms is carried out using the Bellman method. Displacement, stress and temperature are computed and presented graphically. It is found that variation in the thermo-physical properties of a material strongly influences the response to loading. A comparative study with a corresponding homogeneous material is also made. 展开更多
关键词 generalized thermoelasticity functionally graded material (FGM) Green-Lindsay theory vector-matrix differential equation Bellman method
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Improved theory of generalized meteo-ballistic weighting factor functions and their use 被引量:1
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作者 Vladimir CECH Jiri JEVICKY 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2016年第3期242-254,共13页
It follows from the analysis of artillery fire errors that approximately two-thirds of the inaccuracy of indirect artillery fire is caused by inaccuracies in the determination of the meteo parameters included in fire ... It follows from the analysis of artillery fire errors that approximately two-thirds of the inaccuracy of indirect artillery fire is caused by inaccuracies in the determination of the meteo parameters included in fire error budget model.Trajectories calculated under non-standard conditions are considered to be perturbed.The tools utilized for the analysis of perturbed trajectories are weighting factor functions(WFFs)which are a special kind of sensitivity functions.WFFs are used for calculation of meteo ballistic elements B(ballistic wind w B,densityρB,virtual temperatureτB,pressure p B)as well.We have found that the existing theory of WFF calculation has several significant shortcomings.The aim of the article is to present a new,improved theory of generalized WFFs that eliminates the deficiencies found.Using this theory will improve methods for designing firing tables,fire control systems algorithms,and meteo message generation algorithms. 展开更多
关键词 EXTERIOR BallISTIC Non-standard projectile trajectory Perturbation Meteoconditions Sensitivity FUNCTION (generalized) weighting (factor) function(curve) (generalized) EFFECT FUNCTION Norm EFFECT
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Improved design of online fault diagnoser for partially observed Petri nets with generalized mutual exclusion constraints 被引量:2
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作者 Jiufu Liu Wenliang Liu +2 位作者 Jianyong Zhou Yan Sun Zhisheng Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第5期971-978,共8页
This paper investigates the fault detection problem for discrete event systems (DESs) which can be modeled by partially observed Petri nets (POPNs). To overcome the problem of low diagnosability in the POPN online fau... This paper investigates the fault detection problem for discrete event systems (DESs) which can be modeled by partially observed Petri nets (POPNs). To overcome the problem of low diagnosability in the POPN online fault diagnoser in current use, an improved online fault diagnosis algorithm that integrates generalized mutual exclusion constraints (GMECs) and integer linear programming (ILP) is proposed. Assume that the POPN structure and its initial markings are known, and the faults are modeled as unobservable transitions. First, the event sequence is observed and recorded. GMEC is used for elementary diagnosis of the system behavior, then the ILP problem of POPN is solved for further diagnosis. Finally, an example of a real DES to test the new fault diagnoser is analyzed. The proposed algorithm increases the diagnosability of the DES remarkably, and the effectiveness of the new algorithm integrating GMEC and ILP is verified. 展开更多
关键词 fault diagnosis partially observed Petri nets (POPNs) integer linear programming (ILP) generalized mutual exclusion constraints (GMECs)
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PREDICTION OF MAGNETOCRYSTALLINE ANISOTROPY OF POLYCRYSTALLINE MATERIALS WITH GENERALIZED VECTOR METHOD 被引量:1
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《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1991年第7期66-69,共4页
The crystallite orientation distribution functions(ODFs)were determined for the surface, 1/4 depth and 1/2 depth layers of a cold-rolled W20 non-oriented silicon steel sheet.By extending the theory of magnetic anisotr... The crystallite orientation distribution functions(ODFs)were determined for the surface, 1/4 depth and 1/2 depth layers of a cold-rolled W20 non-oriented silicon steel sheet.By extending the theory of magnetic anisotropy to textured materials with no sample symmetry, the variation of magnetic torque versus directions in the plane of the sheet was further calcu- lated quantitatively,which fits well with the measured torque curve. 展开更多
关键词 generalized vector method magnetic torque TEXTURE
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LOGARITHMICALLY IMPROVED REGULARITY CRITERION FOR THE 3D GENERALIZED MAGNETO-HYDRODYNAMIC EQUATIONS 被引量:1
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作者 赵继红 刘桥 《Acta Mathematica Scientia》 SCIE CSCD 2014年第2期568-574,共7页
This article proves the logarithmically improved Serrin's criterion for solutions of the 3D generalized magneto-hydrodynamic equations in terms of the gradient of the velocity field, which can be regarded as improvem... This article proves the logarithmically improved Serrin's criterion for solutions of the 3D generalized magneto-hydrodynamic equations in terms of the gradient of the velocity field, which can be regarded as improvement of results in [10] (Luo Y W. On the regularity of generalized MHD equations. J Math Anal Appl, 2010, 365: 806-808) and [18] (Zhang Z J. Remarks on the regularity criteria for generalized MHD equations. J Math Anal Appl, 2011, 375:799 802). 展开更多
关键词 generalized magneto-hydrodynamic equations regularity criterion multiplier spaces
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Generalized constrained multiobjective games in locally FC-uniform spaces 被引量:1
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作者 丁协平 黎进三 姚任之 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第3期301-309,共9页
A new class of generalized constrained multiobjective games is introduced and studied in locally FC-uniform spaces without convexity structure where the number of players may be finite or infinite and all payoff funct... A new class of generalized constrained multiobjective games is introduced and studied in locally FC-uniform spaces without convexity structure where the number of players may be finite or infinite and all payoff functions get their values in an infinite-dimensional space. By using a Himmelberg type fixed point theorem in locally FC-uniform spaces due to author, some existence theorems of weak Paxeto equilibria for the generalized constrained multiobjective games are established in locally FC-uniform spaces. These theorems improve, unify and generalize the corresponding results in recent literatures. 展开更多
关键词 locally FC-uniform space fixed point generalized constrained multiobjective game weak Pareto equilibria
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Convergence Properties of Generalized Fourier Series on a Parallel Hexagon Domain 被引量:1
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作者 WANG SHU-YUNI LIANG XUEoZHANG +1 位作者 FU YAO SUN XUE-NAN 《Communications in Mathematical Research》 CSCD 2009年第2期104-114,共11页
A new Rogosinski-type kernel function is constructed using kernel function of partial sums Sn(f; t) of generalized Fourier series on a parallel hexagon domain Ω associating with threedirection partition. We prove t... A new Rogosinski-type kernel function is constructed using kernel function of partial sums Sn(f; t) of generalized Fourier series on a parallel hexagon domain Ω associating with threedirection partition. We prove that an operator Wn(f; t) with the new kernel function converges uniformly to any continuous function f(t) ∈ Cn(Ω) (the space of all continuous functions with period Ω) on Ω. Moreover, the convergence order of the operator is presented for the smooth approached function. 展开更多
关键词 three-direction coordinate kernel function generalized Fourier series uniform convergence
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The Structure and the Sufficent and Necessary Conditions for Generalized Statistically Self-Similar Sets 被引量:1
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作者 DENG Ai-jiao HU Di-he (College of Mathematics and Computer Science,Wuhan University,Wuhan 430072,China) 《Wuhan University Journal of Natural Sciences》 CAS 2000年第1期13-21,共9页
We constructed a class of generalized statistically self-similar set.S and give the necessary and sufficent conditions to ensure a random recursive set being a generalized statistically self-similar set. The statist... We constructed a class of generalized statistically self-similar set.S and give the necessary and sufficent conditions to ensure a random recursive set being a generalized statistically self-similar set. The statistically self-similar sets defined by Hutchinson,Falconer,Graf are the special cases of ours. 展开更多
关键词 statistically recursive set generalized statistically self-similar set Hausdorff metric
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EQUILIBRIUM EXISTENCE FOR MULTI-LEADER-FOLLOWER GENERALIZED CONSTRAINED MULTIOBJECTIVE GAMES IN LOCALLY FC-UNIFORM SPACES 被引量:1
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作者 丁协平 《Acta Mathematica Scientia》 SCIE CSCD 2015年第2期339-347,共9页
In this article, we introduce and study some new classes of multi-leader-follower generalized constrained multiobjective games in locally FC-uniform spaces where the number of leaders and followers may be finite or in... In this article, we introduce and study some new classes of multi-leader-follower generalized constrained multiobjective games in locally FC-uniform spaces where the number of leaders and followers may be finite or infinite and the objective functions of the followers obtain their values in infinite-dimensional spaces. Each leader has a constrained correspondence. By using a collective fixed point theorem in locally FC-uniform spaces due to author, some existence theorems of equilibrium points for the multi-leader-follower generalized constrained multiobjective games are established under nonconvex settings. These results generalize some corresponding results in recent literature. 展开更多
关键词 Multi-leader-follower generalized constrained multiobjective games collective fixed point theorem locally FC-uniform space
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