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Research and Application of a Multi-Field Co-Simulation Data Extraction Method Based on Adaptive Infinitesimal Element
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作者 Changfu Wan Wenqiang Li +2 位作者 Sitong Ling Yingdong Liu Jiahao Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期321-348,共28页
Regarding the spatial profile extraction method of a multi-field co-simulation dataset,different extraction directions,locations,and numbers of profileswill greatly affect the representativeness and integrity of data.... Regarding the spatial profile extraction method of a multi-field co-simulation dataset,different extraction directions,locations,and numbers of profileswill greatly affect the representativeness and integrity of data.In this study,a multi-field co-simulation data extractionmethod based on adaptive infinitesimal elements is proposed.Themultifield co-simulation dataset based on related infinitesimal elements is constructed,and the candidate directions of data profile extraction undergo dimension reduction by principal component analysis to determine the direction of data extraction.Based on the fireworks algorithm,the data profile with optimal representativeness is searched adaptively in different data extraction intervals to realize the adaptive calculation of data extraction micro-step length.The multi-field co-simulation data extraction process based on adaptive microelement is established and applied to the data extraction process of the multi-field co-simulation dataset of the sintering furnace.Compared with traditional data extraction methods for multi-field co-simulation,the approximate model constructed by the data extracted from the proposed method has higher construction efficiency.Meanwhile,the relative maximum absolute error,root mean square error,and coefficient of determination of the approximationmodel are better than those of the approximation model constructed by the data extracted from traditional methods,indicating higher accuracy,it is verified that the proposed method demonstrates sound adaptability and extraction efficiency. 展开更多
关键词 Multi-field co-simulation adaptive infinitesimal elements principal component analysis fireworks algorithm sintering furnace simulation
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Comparison of the time-domain electromagnetic field from an infinitesimal point charge and dipole source 被引量:3
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作者 周楠楠 薛国强 王贺元 《Applied Geophysics》 SCIE CSCD 2013年第3期349-356,359,共9页
An electromagnetic field is generated through the accelerating movement of two equal but opposite charges of a single dipole. An electromagnetic field can also be generated by a time-varying infinitesimal point charge... An electromagnetic field is generated through the accelerating movement of two equal but opposite charges of a single dipole. An electromagnetic field can also be generated by a time-varying infinitesimal point charge. In this study, a comparison between the electromagnetic fields of an infinitesimal point charge and a dipole has been presented. First, the time-domain potential function of a point source in a 3D conductive medium is derived. Then the electric and magnetic fields in a 3D homogeneous lossless space are derived via the relation between the potential and field. The field differences between the infinitesimal point charge and the dipole in the step-off time, far-source, and near-source zones are analyzed, and the accuracy of the solutions from these sources is investigated. It is also shown that the field of the infinitesimal point charge in the near-source zone is different from that of the dipole, whereas the far-source zone fields of these two sources are identical. The comparison of real and simulated data shows that the infinitesimal point charge represents the real source better than the divole source. 展开更多
关键词 infinitesimal point charge dipole source TIME-DOMAIN electromagnetic response near-source zone.
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Infinitesimal dividing modeling method for dual suppliers inventory model with random lead times 被引量:2
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作者 Ji Pengcheng Song Shiji Wu Cheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第3期527-536,共10页
As one of the basic inventory cost models, the (Q, τ)inventory cost model of dual suppliers with random procurement lead time is mostly formulated by using the concepts of "effective lead time" and "lead time de... As one of the basic inventory cost models, the (Q, τ)inventory cost model of dual suppliers with random procurement lead time is mostly formulated by using the concepts of "effective lead time" and "lead time demand", which may lead to an imprecise inventory cost. Through the real-time statistic of the inventory quantities, this paper considers the precise (Q, τ) inventory cost model of dual supplier procurement by using an infinitesimal dividing method. The traditional modeling method of the inventory cost for dual supplier procurement includes complex procedures. To reduce the complexity effectively, the presented method investigates the statistics properties in real-time of the inventory quantities with the application of the infinitesimal dividing method. It is proved that the optimal holding and shortage costs of dual supplier procurement are less than those of single supplier procurement respectively. With the assumption that both suppliers have the same distribution of lead times, the convexity of the cost function per unit time is proved. So the optimal solution can be easily obtained by applying the classical convex optimization methods. The numerical examples are given to verify the main conclusions. 展开更多
关键词 INVENTORY precise model random lead times dual supplier infinitesimal dividing method optimiza- tion.
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Characteristic Functional Structure of Infinitesimal Symmetry Transformations for Nonholonomic System 被引量:1
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作者 张宏彬 陈立群 《Journal of Shanghai University(English Edition)》 CAS 2005年第2期134-138,共5页
It was proved that velocity-dependent infinitesima l symmetry transformations of nonholonomic systems have a characteristic functio nal structure, which could be formulated by means of an auxiliary symmetry tra nsform... It was proved that velocity-dependent infinitesima l symmetry transformations of nonholonomic systems have a characteristic functio nal structure, which could be formulated by means of an auxiliary symmetry tra nsformation function and is manifestly dependent upon constants of motion of th e system. An example was given to illustrate the applicability of the results. 展开更多
关键词 analytical mechanics nonholonomic system velocity-dependent infinitesimal symmetry transformation characteristic functional structure constant of motion.
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ON THE INFINITESIMAL ISOMETRIC DEFORMATIONS OF SUBMANIFOLDS
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作者 程新跃 杨文茂 《Acta Mathematica Scientia》 SCIE CSCD 1997年第4期392-404,共13页
In this paper, we consider the infinitesimal I- and Il-isometry deformations of submanifolds immersed in a space form N of constant curvature. We obtain some results which are new even in the case of N being the Eucli... In this paper, we consider the infinitesimal I- and Il-isometry deformations of submanifolds immersed in a space form N of constant curvature. We obtain some results which are new even in the case of N being the Euclidean space. At the same time, we generalize some classical results in E-3 Go the submanifolds immersed in a space form of constant curvature. 展开更多
关键词 infinitesimal isometric deformation mean curvature Gauss-Kronecker curvature sectional curvature
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RELATIONS BETWEEN PERFORMANCE POTENTIALS AND INFINITESIMAL REALIZATION FACTORS IN CLOSED QUEUEING NETWORKS
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作者 YinBaoqun DaiGuiping +1 位作者 XiHongsheng YangXiaoxian 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第4期458-464,共7页
In this paper,the concept of the infinitesimal realization factor is extended to the parameter dependent performance functions in closed queueing networks.Then the concepts of realization matrix (its elements are cal... In this paper,the concept of the infinitesimal realization factor is extended to the parameter dependent performance functions in closed queueing networks.Then the concepts of realization matrix (its elements are called realization factors) and performance potential are introduced,and the relations between infinitesimal realization factors and these two quantities are discussed.This provides a united framework for both IPA and non IPA approaches.Finally,another physical meaning of the service rate is given. 展开更多
关键词 closed queueing networks performance function performance potential realization matrix infinitesimal realization factor.
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From Braided Infinitesimal Bialgebras to Braided Lie Bialgebras
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作者 Shengxiang Wang 《Advances in Pure Mathematics》 2017年第7期366-374,共9页
The present paper is a continuation of [1], where we considered braided infinitesimal Hopf algebras (i.e., infinitesimal Hopf algebras in the Yetter-Drin feld category for any Hopf algebra H), and constructed their Dr... The present paper is a continuation of [1], where we considered braided infinitesimal Hopf algebras (i.e., infinitesimal Hopf algebras in the Yetter-Drin feld category for any Hopf algebra H), and constructed their Drinfeld double as a generalization of Aguiar’s result. In this paper we mainly investigate the necessary and sufficient condition for a braided infinitesimal bialgebra to be a braided Lie bialgebra (i.e., a Lie bialgebra in the category ). 展开更多
关键词 Braided infinitesimal BIALGEBRA Braided LIE BIALGEBRA YETTER-DRINFELD CATEGORY Balanceator
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A Theorem on Infinitesimal I-isometry of Surfaces Immersed in a Space with Constant Curvature
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作者 程新跃 杨文茂 邱敦元 《Chinese Quarterly Journal of Mathematics》 CSCD 1997年第4期63-69, ,共7页
In this paper we discuss the infinitesimal I-isometric de formations of surfaces immersed in a space with constant curvature. We obtain a sufficient condition for the de formation vector field to be zero vector field ... In this paper we discuss the infinitesimal I-isometric de formations of surfaces immersed in a space with constant curvature. We obtain a sufficient condition for the de formation vector field to be zero vector field which is generalization of the results in [1] and [2]. 展开更多
关键词 infinitesimal isometric deformation mean curvature vector sectional curvature
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Influence of Infinitesimal Neglected Effects by Current Theory of Gravitation and Experiments on the Stability of the Universe
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作者 Ping’an Luo 《Journal of Modern Physics》 2014年第15期1437-1449,共13页
From the hypotheses compatible with microphysics theory, this paper establishes a new theoretical model of static universal gravitation and deduces new formula of the theory of universal gravitation. In a first order ... From the hypotheses compatible with microphysics theory, this paper establishes a new theoretical model of static universal gravitation and deduces new formula of the theory of universal gravitation. In a first order approximation, the new formula shows the inverse-square law consistent with Newton formula, which would indicate that the new theory is consistent with the experimental results that can be reasonably explained by the current theory of gravitation. The parameters and higher order terms among the coefficients of this paper reveal the numerous infinitesimal neglected effects by current theory and experiments. In the first order approximation, the meanings of the physical parameters included in coefficients are analyzed and the infinitesimal neglected effects are applied in the study of the stability of the universe, which overcomes the difficulty of singularity in the cosmology of Newton, Einstein, etc., and concludes that the boundary of universe is unlimited, without any need of the hypothesis that the universe starts off with the big bang. Therefore, this paper establishes a harmonious and ingenious relationship between microphysics and macrophysics theories. In addition, through the analysis of the formula derived from the theory of this paper, it is found that: in general, the gravitational constant is not always a constant in the gravitation formula requiring high precision;from the perspective of the interaction of field quantum, the acting force may not be equal to counter-acting force under the interaction of indirect contact;the gravity process is an exothermic process;in the gravitational process, annihilation effects may exist amongst gravitons;reciprocal translation may exist amongst fundamental forces. 展开更多
关键词 Universal GRAVITATION Graviton ANNIHILATION Effect General THEORY of Relativity Steady-State Model of the UNIVERSE infinitesimal
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Infinitesimal Methods in the Works of Thabit ibn Qurra and L, Euler in Spherical Trigonometry
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作者 Golikova N.G. Al-Dabbagh J.J. 《Journal of Mathematics and System Science》 2013年第8期381-384,共4页
In one of his astronomical works the prominent arabic medieval scientists Thabit ibn Qurra (836-901) studied the visible motion of the Sun and found the points, where its velocity is maximum or minimum. He also lbun... In one of his astronomical works the prominent arabic medieval scientists Thabit ibn Qurra (836-901) studied the visible motion of the Sun and found the points, where its velocity is maximum or minimum. He also lbund the points on the ecliptic, where this velocity is equal to the average velocity of the Sun over all the ecliptic. For this purpose he used the idea of infinitely small arcs and their ratios in different points of the circle. The great scientist Leonard Euler (1707-1783) introduced in his works on spherical trigonometry the line-element ds of the surface of the sphere, i.e. the differential of the arc length. He constructed the spherical trigonometry as an inner geometry on the surface of the sphere. He replaced the trigonometry lines, which were in use befbre him, by trigonometric functions. 展开更多
关键词 L.Euler lbn Qurra spherical trigonometry infinitesimals
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Infinitesimally Stability of C~∞ Map-Germs under a Subgroup of A
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作者 邹建成 熊剑飞 《Journal of Mathematical Research and Exposition》 CSCD 1999年第3期539-545,共7页
In [1], tile universal unfolding of Coo map germs under a subgroup of the group A,which is well known group defined by J.Mather [2], was discussed. In this papersSome conditions are given to characterize the infinites... In [1], tile universal unfolding of Coo map germs under a subgroup of the group A,which is well known group defined by J.Mather [2], was discussed. In this papersSome conditions are given to characterize the infinitesimally stability of unfoldings. 展开更多
关键词 map germ universal unfolding infinitesimally stability
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The Extension of Infinitesimal Prolongation Theorem and Its Application
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作者 陈东立 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2003年第2期221-224,共4页
Infinitesimal prolongation theorem is extended from sequences to nets based on κ-saturated nonstandard model. As its an application, a main property about topology of uniform convergence is proved. The proof is much ... Infinitesimal prolongation theorem is extended from sequences to nets based on κ-saturated nonstandard model. As its an application, a main property about topology of uniform convergence is proved. The proof is much simpler than it was, meanwhile the nonstandard characteristics of convergence with respect to u.c. topology is given. 展开更多
关键词 infinitesimal Prolongation Theorem κ-saturation monad of uniformity topology of uniform convergence.
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Infinitesimal nonrigidity of convex surfaces with planar boundary 被引量:1
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作者 LI Chunhe HONG Jiaxing 《Science China Mathematics》 SCIE 2005年第4期513-521,共9页
In the present paper infinitesimal nonrigidity of a class of convex surfaces with planar boundary is given. This result shows that if the image of the Gauss map of an evolution convex surface with planar boundary cove... In the present paper infinitesimal nonrigidity of a class of convex surfaces with planar boundary is given. This result shows that if the image of the Gauss map of an evolution convex surface with planar boundary covers some hemisphere, this surface may be of infinitesimal nonrigidity for the isometric deformation of planar boundary. 展开更多
关键词 infinitesimal nonrigidity CONVEX surface PLANAR boundary.
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Applications of differential algebra for computing Lie algebras of infinitesimal CR-automorphisms 被引量:1
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作者 SABZEVARI Masoud HASHEMI Amir +1 位作者 M.-ALIZADEH Benyamin MERKER Jel 《Science China Mathematics》 SCIE 2014年第9期1811-1834,共24页
We perform detailed computations of Lie algebras of infinitesimal CR-automorphisms associated to three specific model real analytic CR-generic submanifolds in C9by employing differential algebra computer tools—mostly... We perform detailed computations of Lie algebras of infinitesimal CR-automorphisms associated to three specific model real analytic CR-generic submanifolds in C9by employing differential algebra computer tools—mostly within the Maple package DifferentialAlgebra—in order to automate the handling of the arising highly complex linear systems of PDE’s.Before treating these new examples which prolong previous works of Beloshapka,of Shananina and of Mamai,we provide general formulas for the explicitation of the concerned PDE systems that are valid in arbitrary codimension k 1 and in any CR dimension n 1.Also,we show how Ritt’s reduction algorithm can be adapted to the case under interest,where the concerned PDE systems admit so-called complex conjugations. 展开更多
关键词 differential algebra differential polynomial ring Ritt reduction algorithm Rosenfeld-Grbner algorithm CR-manifolds Lie algebras of infinitesimal CR-automorphisms
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ON THE TRICOMI PROBLEM OF INFINITESIMAL DEFORMATION EQUATION FOR SURFACES WITH MIXED CURVATURE(Ⅱ)——EXISTENCE OF SOLUTION
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作者 孙和生 《Science China Mathematics》 SCIE 1992年第2期142-147,共6页
In this paper, the L, weak solution and H^1 strong solution to the Tricomi problem of in-finitesimal deformation equation for surfaces witb a mixed curvatute are proved under veryweak conditions.
关键词 infinitesimal DEFORMATION EQUATION of surface with MIXED CURVATURE EQUATION of MIXED type Tricomi problem existence of solution.
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Equivalent construction of the infinitesimal time translation operator in algebraic dynamics algorithm for partial differential evolution equation
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作者 LIU ChengShi Department of Mathematics, Northeast Petroleum University, Daqing 163318, China 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2010年第8期1475-1480,共6页
We give an equivalent construction of the infinitesimal time translation operator for partial differential evolution equation in the algebraic dynamics algorithm proposed by Shun-Jin Wang and his students. Our constru... We give an equivalent construction of the infinitesimal time translation operator for partial differential evolution equation in the algebraic dynamics algorithm proposed by Shun-Jin Wang and his students. Our construction involves only simple partial differentials and avoids the derivative terms of δ function which appear in the course of computation by means of Wang-Zhang operator. We prove Wang’s equivalent theorem which says that our construction and Wang-Zhang’s are equivalent. We use our construction to deal with several typical equations such as nonlinear advection equation, Burgers equation, nonlinear Schrodinger equation, KdV equation and sine-Gordon equation, and obtain at least second order approximate solutions to them. These equations include the cases of real and complex field variables and the cases of the first and the second order time derivatives. 展开更多
关键词 ALGEBRAIC dynamics infinitesimal TIME TRANSLATION OPERATOR partial differential evolution equation
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High-order field theory and a weak Euler–Lagrange–Barut equation for classical relativistic particle-field systems
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作者 范培锋 陈强 +1 位作者 肖建元 于治 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第11期42-54,共13页
In both quantum and classical field systems,conservation laws such as the conservation of energy and momentum are widely regarded as fundamental properties.A broadly accepted approach to deriving conservation laws is ... In both quantum and classical field systems,conservation laws such as the conservation of energy and momentum are widely regarded as fundamental properties.A broadly accepted approach to deriving conservation laws is built using Noether's method.However,this procedure is still unclear for relativistic particle-field systems where particles are regarded as classical world lines.In the present study,we establish a general manifestly covariant or geometric field theory for classical relativistic particle-field systems.In contrast to quantum systems,where particles are viewed as quantum fields,classical relativistic particle-field systems present specific challenges.These challenges arise from two sides.The first comes from the mass-shell constraint.To deal with the mass-shell constraint,the Euler–Lagrange–Barut(ELB)equation is used to determine the particle's world lines in the four-dimensional(4D)Minkowski space.Besides,the infinitesimal criterion,which is a differential equation in formal field theory,is reconstructed by an integro-differential form.The other difficulty is that fields and particles depend on heterogeneous manifolds.To overcome this challenge,we propose using a weak version of the ELB equation that allows us to connect local conservation laws and continuous symmetries in classical relativistic particle-field systems.By applying a weak ELB equation to classical relativistic particle-field systems,we can systematically derive local conservation laws by examining the underlying symmetries of the system.Our proposed approach provides a new perspective on understanding conservation laws in classical relativistic particle-field systems. 展开更多
关键词 high-order field theory weak Euler-Lagrange-Barut equation infinitesimal criterion of symmetric condition Noether's theorem geometric conservation laws
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Why Is an Integral an Accurate Value?
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作者 Wenbing Wu Xiaojian Yuan 《Applied Mathematics》 2023年第12期847-850,共4页
The derivative and integral in calculus are both exact values. To explain this reason, the integration interval can be infinitely subdivided. The difference in area between curved trapezoids and rectangles can be expl... The derivative and integral in calculus are both exact values. To explain this reason, the integration interval can be infinitely subdivided. The difference in area between curved trapezoids and rectangles can be explained by the theory of higher-order infinitesimal, leading to the conclusion that the difference between the two is an infinitesimal value. From this, it can be inferred that the result obtained by integration is indeed an accurate value. 展开更多
关键词 INTEGRAL infinitesimal Curved Trapezoid Accurate Value
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Could Long-Term Stability Last Forever?
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作者 Maria K. Koleva 《Journal of Modern Physics》 CAS 2023年第4期450-460,共11页
The subject of the present paper is to prove that the recently introduced conjecture of boundedness puts a ban over the view of stability as asymptotic property. This result comes in sharp contrast with the prescripti... The subject of the present paper is to prove that the recently introduced conjecture of boundedness puts a ban over the view of stability as asymptotic property. This result comes in sharp contrast with the prescription of the traditional thermodynamics and statistical physics which consider the existence of equilibrium as asymptotic property of all systems. The difference commences from the use of infinitesimal calculus as the basic implement for modelling by the latter while the primary premise of the conjecture of boundedness is sustaining the energy/matter/information permanently bounded and finite. The latter property overrules the infinitesimal calculus as the major implement of modelling because, among all, it is proven that the traditional one suffers unsoluble difficulties. 展开更多
关键词 Long-Term Stability Equilibrium infinitesimal Calculus BOUNDEDNESS Decomposition Theorem Certain Information Universal Mechanism for Collapse
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DIFFERENTIABILITY OF C_0-SEMIGROUPS WITH APPLICATION
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作者 金振东 喻文焕 +1 位作者 靳展 王辅敏 《Transactions of Tianjin University》 EI CAS 1999年第2期25-29,共5页
This paper considers the differentiability of C 0 semigroups with respect to (w.r.t.) parameters contained in their infinitesimal generators.It is proved that the generalized continuity and strong differentiability ... This paper considers the differentiability of C 0 semigroups with respect to (w.r.t.) parameters contained in their infinitesimal generators.It is proved that the generalized continuity and strong differentiability of their infinitesimal generators w.r.t.parameters imply the differentiability of the C 0 semigroups.The results are applied to the differentiability of the solution of a linear delay differential equation w.r.t.its delays. 展开更多
关键词 C 0 semigroup infinitesimal generator generalized continuity strongly Frechet differential dalay equation
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