In this paper, firstly we study the series ma intenance system with two components, obtain its exsistence and uniqueness of a dynamic state nonnegative solution by strongly continuous semigroups of operator s theory. ...In this paper, firstly we study the series ma intenance system with two components, obtain its exsistence and uniqueness of a dynamic state nonnegative solution by strongly continuous semigroups of operator s theory. Then we prove that 0 is the eigenvalue of the system’s host operators, a nd finally we study the eigenvector of the eigenvalue 0.展开更多
For a maximal subgroup M of a group G, a g-completion for M is a subgroup C such that C is not contained in M while MG, the core of M in G, is contained in C and C/MG has no proper normal subgroup of G/MG. This concep...For a maximal subgroup M of a group G, a g-completion for M is a subgroup C such that C is not contained in M while MG, the core of M in G, is contained in C and C/MG has no proper normal subgroup of G/MG. This concept was introduced by ZHAO Yao-qing in 1998. In this paper we characterize the solvability of finite groups by means of g-completions and obtain some new results.展开更多
In this paper, we obtain some global existence results for the higher-dimensionai nonhomogeneous, linear, semilinear and nonlinear thermoviscoelastic systems by using semigroup approach.
We establish the exponential stability of global solutions and C0-semigroup for the compressible Navier.Stokes equations of a viscous polytropic ideal gas in both bounded domain in R^1 and bounded annular domains in R...We establish the exponential stability of global solutions and C0-semigroup for the compressible Navier.Stokes equations of a viscous polytropic ideal gas in both bounded domain in R^1 and bounded annular domains in R^n （n=2,3）.展开更多
In this paper, the properties of the heat diffusion semigroup {e^(t△)}_(t≥0) generated by the Hodge-deRham operator in a Riemannian manifold are discussed.
The last decade was marked by the special interest in flora, biological characteristics, its adaptation to climate fluctuations and the influence of human activities. The steppe climate is generally characterized by i...The last decade was marked by the special interest in flora, biological characteristics, its adaptation to climate fluctuations and the influence of human activities. The steppe climate is generally characterized by its heterogeneity. The lower semi-arid： 300 mm to 400 mm per year; The arid higher： 200 mm to 300 mm per year; The arid lower： between 100 mm and 200 mm per year. Its wide analysis of a region is based on data provided by weather stations; a summary of the climate study area was analyzed with representative stations （Ain Sefra, El Aricha, Ras el-Ma, Saf-Saf）. This steppe is in various states of degradation, consisting of Stipa tenacissima, Artemisia herba alba, Biscutella didyma, Spartium junceum and Lepidium glastifolium, etc..展开更多
We studied the influence of soil heterogeneity on plant community structure in a semiarid region of Central Mexico using Bray-Curtis Ordination. The results showed that some edaphic factors, such as soil depth, organi...We studied the influence of soil heterogeneity on plant community structure in a semiarid region of Central Mexico using Bray-Curtis Ordination. The results showed that some edaphic factors, such as soil depth, organic matter, and potassium and calcium content, explained 80% of the total variation in structure of the studied communities. We found that soil resources were heterogeneously distributed in the study area, indicating that the edaphic variables considered in this study explain the existing plant community variability, moreover the presence of some shrubs as Krameria cytisoides influences the soil properties, suggesting that there is a reciprocal effect between plant and soil.展开更多
Let S be an antinegative commutative semiring having no zero divisions or finite general Boolean Algebra and μ(S) the set of n×n matrices over S. In this paper we characterize the structure of the senigroup n,...Let S be an antinegative commutative semiring having no zero divisions or finite general Boolean Algebra and μ(S) the set of n×n matrices over S. In this paper we characterize the structure of the senigroup n,(S) of linear operators on μn,(S) that strongly preserve the M-P inverses of matrices.展开更多
By using the strong continuous semigroup theory of linear operators we prove the existence of a unique positive time-dependent solution of the model describing a re-pairable, standby, human & machine system.
Exponential stability of the first order singular distributed parameter systems is discussedin the light of degenerate semi-group methods,which is described by the abstract developing equationin Hilbert space.The nece...Exponential stability of the first order singular distributed parameter systems is discussedin the light of degenerate semi-group methods,which is described by the abstract developing equationin Hilbert space.The necessary and sufficient conditions concerning the exponential stability of thefirst order singular distributed parameter systems are given.展开更多
The exponential stability of a multi-state device is discussed in this paper. We present that the Co-semigroup generated by the system operator is quasi-compact and irreducible. It is known that 0 is a simple eigenval...The exponential stability of a multi-state device is discussed in this paper. We present that the Co-semigroup generated by the system operator is quasi-compact and irreducible. It is known that 0 is a simple eigenvalue of the system operator. In combination with this, we obtain that the time-dependent solution exponentially converges to the steady-state solution, which is the positive eigenfuction corresponding to the simple eigenvalue O.展开更多
The perturbation of semigroup by a multiplicative functional with bounded variation is investigated in the frame of weak duality. The strong continuity and Schrodinger type equation of the perturbated semigroup are di...The perturbation of semigroup by a multiplicative functional with bounded variation is investigated in the frame of weak duality. The strong continuity and Schrodinger type equation of the perturbated semigroup are discussed. A few switching identities and formulae conerning dual additive functionals and Revuz measures are given.展开更多
文摘In this paper, firstly we study the series ma intenance system with two components, obtain its exsistence and uniqueness of a dynamic state nonnegative solution by strongly continuous semigroups of operator s theory. Then we prove that 0 is the eigenvalue of the system’s host operators, a nd finally we study the eigenvector of the eigenvalue 0.
文摘For a maximal subgroup M of a group G, a g-completion for M is a subgroup C such that C is not contained in M while MG, the core of M in G, is contained in C and C/MG has no proper normal subgroup of G/MG. This concept was introduced by ZHAO Yao-qing in 1998. In this paper we characterize the solvability of finite groups by means of g-completions and obtain some new results.
基金Supported by the NNSF of China(10571024, 10871040)
文摘In this paper, we obtain some global existence results for the higher-dimensionai nonhomogeneous, linear, semilinear and nonlinear thermoviscoelastic systems by using semigroup approach.
基金Foundation item: Supported by the NSF of ChinaSupported by the Prominent Youth from Henan Province(0412000100)
文摘We establish the exponential stability of global solutions and C0-semigroup for the compressible Navier.Stokes equations of a viscous polytropic ideal gas in both bounded domain in R^1 and bounded annular domains in R^n （n=2,3）.
文摘In this paper, the properties of the heat diffusion semigroup {e^(t△)}_(t≥0) generated by the Hodge-deRham operator in a Riemannian manifold are discussed.
文摘The last decade was marked by the special interest in flora, biological characteristics, its adaptation to climate fluctuations and the influence of human activities. The steppe climate is generally characterized by its heterogeneity. The lower semi-arid： 300 mm to 400 mm per year; The arid higher： 200 mm to 300 mm per year; The arid lower： between 100 mm and 200 mm per year. Its wide analysis of a region is based on data provided by weather stations; a summary of the climate study area was analyzed with representative stations （Ain Sefra, El Aricha, Ras el-Ma, Saf-Saf）. This steppe is in various states of degradation, consisting of Stipa tenacissima, Artemisia herba alba, Biscutella didyma, Spartium junceum and Lepidium glastifolium, etc..
文摘We studied the influence of soil heterogeneity on plant community structure in a semiarid region of Central Mexico using Bray-Curtis Ordination. The results showed that some edaphic factors, such as soil depth, organic matter, and potassium and calcium content, explained 80% of the total variation in structure of the studied communities. We found that soil resources were heterogeneously distributed in the study area, indicating that the edaphic variables considered in this study explain the existing plant community variability, moreover the presence of some shrubs as Krameria cytisoides influences the soil properties, suggesting that there is a reciprocal effect between plant and soil.
文摘Let S be an antinegative commutative semiring having no zero divisions or finite general Boolean Algebra and μ(S) the set of n×n matrices over S. In this paper we characterize the structure of the senigroup n,(S) of linear operators on μn,(S) that strongly preserve the M-P inverses of matrices.
基金This research is supported by the Tianyuan Mathematics Foundation (No. 10226007) and the Science Foundation of Xinjiang University
文摘By using the strong continuous semigroup theory of linear operators we prove the existence of a unique positive time-dependent solution of the model describing a re-pairable, standby, human & machine system.
基金This research is supported by the National Natural Science Foundation of China under Grant No.60674018.
文摘Exponential stability of the first order singular distributed parameter systems is discussedin the light of degenerate semi-group methods,which is described by the abstract developing equationin Hilbert space.The necessary and sufficient conditions concerning the exponential stability of thefirst order singular distributed parameter systems are given.
基金The research is supported by Beijing Institute of Technology Foundation under Grant No.20060742011.
文摘The exponential stability of a multi-state device is discussed in this paper. We present that the Co-semigroup generated by the system operator is quasi-compact and irreducible. It is known that 0 is a simple eigenvalue of the system operator. In combination with this, we obtain that the time-dependent solution exponentially converges to the steady-state solution, which is the positive eigenfuction corresponding to the simple eigenvalue O.
基金Project supported in part by the National Natural Science Foundation of China (No.19501035).
文摘The perturbation of semigroup by a multiplicative functional with bounded variation is investigated in the frame of weak duality. The strong continuity and Schrodinger type equation of the perturbated semigroup are discussed. A few switching identities and formulae conerning dual additive functionals and Revuz measures are given.
