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Acta Mathematica Sinica, Chinese Series 1997 Vol.40

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Hierarchy Structures of Phase Spaces on Linear Logic

YouLiang Hou,DePei Liu

Acta Mathematica Sinica, Chinese Series    1997, 40 (1): 1-008.   DOI: 10.12386/A1997sxxb0001
Abstract2317)      PDF(pc) (408KB)(738)       Save
In this paper the algebraic structures of phase spaces are investigated. The phase spaces with hierarchy are defined and a property of the least subspaces of a phase space is given. According to these results, some characteristics of linear tautologies are discussed.
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On the Existence of the Optimal Measurable Coupling of Transition Probablity
ShaoYi Zhang,Kan Xu
Acta Mathematica Sinica, Chinese Series    1997, 40 (1): 5-13.   DOI: 10.12386/A1997sxxb0002
Abstract2394)      PDF(pc) (478KB)(835)       Save
In this paper, by the method of stochastic linear programming and some skill in s-space, we give a proof for the existence of the optimal measurable coupling of transition probability.
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Some Genenalizations to Several Dimensions of the Pedoe Inequality with Applications
GangSong Leng,LiHua Tang
Acta Mathematica Sinica, Chinese Series    1997, 40 (1): 14-21.   DOI: 10.12386/A1997sxxb0003
Abstract2904)      PDF(pc) (408KB)(785)       Save
In this paper, we establish some inequalities involving two n-dimensional simplexes in Euclidean space En, which are generalizations of the well-known Pedoe inequality, and prove some applications thereof.
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The Comparison between Arbitrary Information Sources and Nonhomogeneous Markov Information Sources and the Small Deviations Theorems
Wen Liu(1),WeiGuo YANG(2)
Acta Mathematica Sinica, Chinese Series    1997, 40 (1): 22-36.   DOI: 10.12386/A1997sxxb0004
Abstract2563)      PDF(pc) (430KB)(1165)       Save
Let {Xn, n≥0} be a sequence of measurable functions taking their values in the alphabet S = {1,2,…, N}. Let P,Q be two probability measures on the measurable space, such that {Xn,n ≥ 0} is Markovian under Q, Let h(P \ Q) = limsupn-1 log[P(X0,…, Xn)/Q(X0,…, Xn)} be the sample divergence-rate distance n→∞ of P relative to Q. In this paper, a class of small deviations theorems for the averages of the functions of two variables of an arbitrary information sources are discussed by using the concept h(P \ Q), and, as a corollary, a small deviations theorem for the entropy densities of arbitrary information sources is obtained. Finally, an extension of Shannon-McMillan Theorem on the case of nonhomogeneous Markov information sources is given.
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On Dirichlet Problem for One Class of Nonlinear Equations
ChunPeng Yang(1),Rong Wu(2)
Acta Mathematica Sinica, Chinese Series    1997, 40 (1): 37-42.   DOI: 10.12386/A1997sxxb0005
Abstract2743)      PDF(pc) (393KB)(1002)       Save
Suppose D is a nonempty regular open set in Rd (d≥ 3). This paper gives the usual formula of the nonegative bounded solution for the Dirichlet problem for one class of nonlinear equations by using super Brownian motion. Under some conditions, this paper proves the existence and the uniqueness for the Dirichlet problem have fixed limit at infinity and obtain the probabilistic formula and extended some results in [4].
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Lumer-Phillips Theorem for C-Semigroups and C-Hemitian Operators
YangRong Li
Acta Mathematica Sinica, Chinese Series    1997, 40 (1): 43-52.   DOI: 10.12386/A1997sxxb0006
Abstract3148)      PDF(pc) (440KB)(816)       Save
We give a sufficient condition, for a densely defined operator A, generating a contract C-semigroup, which is also necessary if C is a isometric operator, this generalize the Lumer-Phillips theorem; moreover, we use this result to describe the generators of isometric C-semigroups.
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Global Existence and Uniqueness, Oscillation and Nonoscillation of Impulsive Delay Differential Equations
JianHua Shen
Acta Mathematica Sinica, Chinese Series    1997, 40 (1): 53-59.   DOI: 10.12386/A1997sxxb0007
Abstract4132)      PDF(pc) (416KB)(941)       Save
Consider the impulsive delay differential equation We obtain a global existence and uniqueness theorem of solutions of Eq.(E). General impulsive perturbed conditions are also obtained for the oscillatory or nonoscillatory behavior of all solutions when the corresponding linear delay differential equations has same behavior.
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The Existence of Hamonic Maps with Free Boundaries
DeLiang XU
Acta Mathematica Sinica, Chinese Series    1997, 40 (1): 60-66.   DOI: 10.12386/A1997sxxb0008
Abstract2719)      PDF(pc) (490KB)(822)       Save
We study the existence of hamonic maps with free boundaries from disk into Riemannian manifolds. By using the perturbation technique of Sacks-Uhlenbeck, and the estimate of morse index of hamonic maps, we obtain some existence results.
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On Theta Pairs for Maximal Subgroups of Finite Groups
YaoQing Zhao
Acta Mathematica Sinica, Chinese Series    1997, 40 (1): 67-72.   DOI: 10.12386/A1997sxxb0009
Abstract3142)      PDF(pc) (392KB)(720)       Save
In the paper "On theta pairs for a maximal subgroup" (Proc. Amer. Math. Soc., V109N3(1990)), N.P. Mukherjee and P.Bhattacharya denned the concept of θ-pairs associated to a maximal subgroup of a finite group, studied the influence of θ-pairs on the structure of the group itself and obtained several results. In this paper we study first the further properties of θ-pairs, then improve in essence some of the main results in Mukherjee and Bhattacharya's paper by using these properties and deal with some new conditions which are necessary and sufficient for a group to be solvable or nilpotent.
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The Duality of Relative Hopf Modules
LiangYun Zhang
Acta Mathematica Sinica, Chinese Series    1997, 40 (1): 73-79.   DOI: 10.12386/A1997sxxb0010
Abstract2609)      PDF(pc) (337KB)(904)       Save
In this paper, we give the duality properties of relative Hopf modules. At first, we prove that the duality modules of relative Hopf modules are still relative Hopf modules. Then, we give the basic structure theorem and Maschke's theorem to the duality relative Hopf modules of relative Hopf modules.
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The Existence and Uniqueness and Stability of Almost Periodic Solutions
QuanYi Wang
Acta Mathematica Sinica, Chinese Series    1997, 40 (1): 80-89.   DOI: 10.12386/A1997sxxb0011
Abstract7049)      PDF(pc) (418KB)(885)       Save
This paper gives some sufficient conditions which ganrantee the existence and uniqueness and stability and instability of periodic solutions and almost periodic solutions and the estimate on the existence bound of the periodic solutions for some differential equations. Our results extend the main results in [1] and the relative results in [2-6].
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The Uncertainty Principle and Uniqueness of the Cauchy Problem
WeiKe Wang
Acta Mathematica Sinica, Chinese Series    1997, 40 (1): 90-99.   DOI: 10.12386/A1997sxxb0012
Abstract3724)      PDF(pc) (476KB)(717)       Save
This article apply the idea of the uncertainty principle to consider the uniqueness of the Cauchy problems for second order elliptic operators with non-smooth characteristics. We first construct a decomposition of function and study the Carleman estimate in the micro-local sense, then we prove the uniqueness of the Cauchy problems in more general cases.
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Oscillation of Systems of Hyperbolic Differential Equations with Deviating Arguments
YongKun Li
Acta Mathematica Sinica, Chinese Series    1997, 40 (1): 100-105.   DOI: 10.12386/A1997sxxb0013
Abstract3333)      PDF(pc) (364KB)(962)       Save
In this paper, sufficient conditions are obtained for the oscillation of all solutions of the homogeneous Neumann, Dirichlet and Robin's boundary value problems associated with the hyperbolic system for i = 1, 2, ???, m, (x, t) ? ft x (0, oo), $1 C Rn, where A denotes the Laplacian in E".
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Strong Converse Inequality for Bernstein Type Operators
Song Li
Acta Mathematica Sinica, Chinese Series    1997, 40 (1): 106-121.   DOI: 10.12386/A1997sxxb0014
Abstract3006)      PDF(pc) (370KB)(785)       Save
For Szasz-Mirakian operator Sn, Bernstein operator Bn and Baskakov operators Vn, we prove that there exists a constant C > 0 such that wψ12 (f; 1/n~1/n)≤ and and hold for all where and denote Ditzian-Totik moduli of smoothness.
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Generalized Morrey Space and Generalized Campanato Space and Their Application (Ⅰ)
CongXin Wu,YongQiang Fu
Acta Mathematica Sinica, Chinese Series    1997, 40 (1): 122-128.   DOI: 10.12386/A1997sxxb0015
Abstract3025)      PDF(pc) (366KB)(828)       Save
Campanato space is widely used to study partial differential equation. Thus in this paper we generalize Morrey space and Campanato space, and study the properties of the introduced generalized Morrey space and generalized Campanato space. In another paper, we obtain the regularity for nonpower growth elliptic partial differential equation by means of generalized Campanato space.
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L~p Boundedness for Oscillatory Singular Integrals
QiRong Qiu
Acta Mathematica Sinica, Chinese Series    1997, 40 (1): 129-132.   DOI: 10.12386/A1997sxxb0016
Abstract4163)      PDF(pc) (280KB)(1041)       Save
This paper considers the following oscillatory singular integrals: Tf(x)= P.V. ∫Rn eip(x-y)K(x - y)f(x)dy, where K(y) = Ω(y)/||y||n and ∫Sn-1Ω(y)dσ(y) = 0. For P which satisfies certain convex condition andΩ∈ Lq(Sn-1) (q > 1), we prove that T is bounded on Lp(Rn), p > 1.
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Inequalities of Hardy Martingales and Convexity in Complex Space
DePei Liu(1),Turdebek N. Bekja
Acta Mathematica Sinica, Chinese Series    1997, 40 (1): 133-143.   DOI: 10.12386/A1997sxxb0017
Abstract3275)      PDF(pc) (491KB)(923)       Save
In this paper we study the relationships of inequalities of Hardy martingales with values in complex quasi-Banach space and analytic uniform convexity of the space, prove weak (1,1), strong (p,p) and convex φ-function inequalities of q-mean-square function of Hardy martingales, and using them give characterizations of analytic q-uniform convexifiablity of complex space. In the same time we characterize the same property by using Banach-space-valued analytic functions and Brown motion in unit disk of complex plane.
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On a Problem of Heilbronn Type in Higher Dimensional Space
Yi Hong,GuoQiang Wang,ZhiSui T
Acta Mathematica Sinica, Chinese Series    1997, 40 (1): 144-153.   DOI: 10.12386/A1997sxxb0018
Abstract2894)      PDF(pc) (552KB)(900)       Save
The following problem of Heilbronn type is considered. Let S Rk be a set consists of n points A1, A2,…,An, d(S)=min{AiAj|1≤i
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The Algebras Having Singular Value Decomposition Property
LiPing Huang
Acta Mathematica Sinica, Chinese Series    1997, 40 (2): 161-166.   DOI: 10.12386/A1997sxxb0019
Abstract2862)      PDF(pc) (396KB)(860)       Save
Let F be a field, R an F-algebra with an involution, if any matrix over R has a singular value decomposition (SVD for short), then R is said to have the SVD property. This paper shows that: R is an F-algebra having the SVD property if and only if R is isomorphic to either R+ or R+(-1~1/-1) or the quaternion field (-1,-1/R+) over R+, where R+ is the set of all symmetric elements of R, and R+ is a Galois order closed field.
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FP-selfinjective Dimension over Non-commutative Coherent Rings
ZhaoYong Huang
Acta Mathematica Sinica, Chinese Series    1997, 40 (2): 167-174.   DOI: 10.12386/A1997sxxb0020
Abstract2745)      PDF(pc) (410KB)(771)       Save
In this paper, we introduce the notion of Wn-modules and describe non-commutative coherent rings with finite FP-selfinjective dimension. The obtained results generalize the works of Stentrom and Bass. Finally we apply these results to extension closed categories of modules.
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On Real Hilbert Rings
GuangXing Zeng,ZhiZhong Dai
Acta Mathematica Sinica, Chinese Series    1997, 40 (2): 175-184.   DOI: 10.12386/A1997sxxb0021
Abstract2644)      PDF(pc) (495KB)(789)       Save
In this paper, by introducing the notion of a strongly real Hilbert ring, we show that (1) A ring A is a strqngly real Hilbert ring if and only if A[X] is a real Hilbert ring; and (2) A ring A is a strongly real Hilbert ring if and only if every real maximal ideal of A[X]contracts in A to a real maximal ideal. Thereby, the two main results listed in reference [1] are negated. Moreover, the so-called strictly real Hilbert rings are investigated; these rings are of significance for the discussion of the semialgebraic Nullstellensatz.
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A Generalization of Ekeland's Variational Principle and Applications
ChengKui Zhong
Acta Mathematica Sinica, Chinese Series    1997, 40 (2): 185-190.   DOI: 10.12386/A1997sxxb0022
Abstract2761)      PDF(pc) (367KB)(784)       Save
This paper first generalizes Ekeland's variational principle and then considers the relation between (P.S.) condition and coercivity of functional.
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Nonlinear Ergodic Theorems for Commutative Semigroups in Banach Spaces
Gang Li(1),JiPu Ma(2)
Acta Mathematica Sinica, Chinese Series    1997, 40 (2): 191-201.   DOI: 10.12386/A1997sxxb0023
Abstract2958)      PDF(pc) (445KB)(783)       Save
In this paper, we provide nonlinear ergodic theorems and weak convergence theorems for commutative semigroups of asymptotically nonexpansive type mappings iu uniformly convex Banach spaces that satisfy opial's condition or have a Frechet differentiable norm.
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On the Closed Spherical Curves and Jacobi Theorem

YouNing Wang,JiZhi Liu

Acta Mathematica Sinica, Chinese Series    1997, 40 (2): 202-206.   DOI: 10.12386/A1997sxxb0024
Abstract2447)      PDF(pc) (362KB)(705)       Save
An answer to the problem formulated by W. Fenchel[1] is obtained. A global property of spherical curves is given and applied to generalize Jacobi theorem on closed space curves.
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Some Surjectivity Theorems for Compact Perturbations of M-Accretive Operators
HaiYun Zhou
Acta Mathematica Sinica, Chinese Series    1997, 40 (2): 207-212.   DOI: 10.12386/A1997sxxb0025
Abstract3053)      PDF(pc) (364KB)(826)       Save
In the present paper we establish some surjectivity theorems for the operators A and C, where A is m-accretive and C is compact. Our results generalize and improve the main results of Zhu[5].
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Melnikov Vectors and Transversal Heteroclinic Orbits in Degenerate Cases
WeiYao Zeng(1),ZhuJun Jing(2)
Acta Mathematica Sinica, Chinese Series    1997, 40 (2): 213-220.   DOI: 10.12386/A1997sxxb0026
Abstract2546)      PDF(pc) (425KB)(739)       Save
In this paper, by using the theory of exponential dichotomies and functional analystic method, we investigate the degenerate heteroclinic bifurcation of the systems whose unperturbed equations have not heteroclinic manifold. The sufficient condition assuring the existence of transversal heteroclinic orbits is given by making use of Melnikov vector.
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Γ-Rings for Which the Jacoboson Radical Equals the Simplical Radical in All Homomorphic Images
DingGuo Wang
Acta Mathematica Sinica, Chinese Series    1997, 40 (2): 221-226.   DOI: 10.12386/A1997sxxb0027
Abstract2858)      PDF(pc) (408KB)(779)       Save
Let M be a Γ-ring in the sense of Nobusawa.The ring M2=(RΓML) was defined by Kyuno. In this paper, first we characterise primitive ideals and the Jacobson radical of M2. Next, we introduce a new class of Γ-rings in which, for every homomorphic image, the Jacobson radical equals the simplicial radical. We shall call this the class of PM-Γ-rings. Relationships between PM properties of Γ-ring M and the corresponding properties of Γn,m-ring Mm,n, the right operator ring R of Γ-ring M, M-ring Γ and the ring M2 are established. Finally, we give a general version of Jacobson properties for Γ-rings, which includes also Jacobson property, Brown-McCoy property and PM property.
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Global Structure of Solutions of Superlinear Singular Boundary Value Problems
XiYu Liu
Acta Mathematica Sinica, Chinese Series    1997, 40 (2): 227-234.   DOI: 10.12386/A1997sxxb0028
Abstract4893)      PDF(pc) (470KB)(812)       Save
This paper deals with a kind of superlinear boundary value problems with singularity. We prove continua to the solution set exist. Our corollary improves the main results of [1] to some extent, and we drop their main condition off.
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Martingales with Respect to Complex Measures with b_p~+(K) Condition
YouLiang Hou,PeiDe Liu
Acta Mathematica Sinica, Chinese Series    1997, 40 (2): 235-245.   DOI: 10.12386/A1997sxxb0029
Abstract3108)      PDF(pc) (507KB)(751)       Save
This paper discussed the complex measure dμ= ψdv where the complex valued function ψ∈ Lloc1 and some properties of conditional expectations and matin-gales with respect to the measure dμ. Then it proved that the maximal operators of the martingales are week (p, p) bounded and strong (p, p) bounded if ψsatisfies bp+(K) condition and that the square operators of the martingales are L2-bounded if ψ satisfies b∞+(K) ∩ a1(K) condition.
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The Uniqueness of Limit Cycles Bifurcated from a Heteroclinic Loop
MaoAn Han
Acta Mathematica Sinica, Chinese Series    1997, 40 (2): 246-252.   DOI: 10.12386/A1997sxxb0030
Abstract2947)      PDF(pc) (415KB)(798)       Save
The limit cycle bifurcations near a heteroclinic loop with two or three saddle points are studied. The uniqueness of limit cycles is proved uader a simple condition, and a necessary and sufficient condition for a limit cycle to exist is obtained. As an application to a codimension two bifurcation in a three dimensional system, the problem on the uniqueness of limit cycles near a heteroclinic loop of the deduced plane system is solved.
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On the C~∞-solutions of the Feigenbaum Function Equation
YuanSheng Tang
Acta Mathematica Sinica, Chinese Series    1997, 40 (2): 253-258.   DOI: 10.12386/A1997sxxb0031
Abstract2576)      PDF(pc) (374KB)(851)       Save
In this paper, we construct some even continuous solutions of the Feigen-baum Function Equation. For every 0 < λ < 1, we give out some C∞-even-solutions of this equation.
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Quasisimilarity of Operators and (Q) Operators
Chen Lin,ZiKun Yan
Acta Mathematica Sinica, Chinese Series    1997, 40 (2): 259-264.   DOI: 10.12386/A1997sxxb0032
Abstract4467)      PDF(pc) (396KB)(807)       Save
In this paper, we introduce the conceptions S∈ (Q) S∈ L(H) with σe(S) C σe(T) for every operator T quasisimilar to S, β(S) = {λ∈C : a neighbourhood U of λ such that (S -z) ○(V,H) is closed for every neighbour hood V of λ, V U}, characterize (Q) operators by means of β(S) and show that the family of (Q) operators includes many familiar operators (such as subdecompasable, M-hyponormal, semi-hyponormal operators, etc.) and is norm-dense in L(H).
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Poisson Limit Law for Markov Chains in Markovian Environments
HanXing Wang,YongLong Dai
Acta Mathematica Sinica, Chinese Series    1997, 40 (2): 265-270.   DOI: 10.12386/A1997sxxb0033
Abstract2581)      PDF(pc) (374KB)(861)       Save
A Markov chain in markovian environment is studied in this paper. For this process we prove a limit law for the recurrence to small cylindrical sets. Moreover, we give a sufficient condition for the process being φ-mixing, and give a exponential estimation of the probability for the process to return to small cylindrical sets.
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Moment Inequality for Mixing Sequences and Nonparametric Estimation

ShanChao Yang

Acta Mathematica Sinica, Chinese Series    1997, 40 (2): 271-279.   DOI: 10.12386/A1997sxxb0034
Abstract3072)      PDF(pc) (485KB)(976)       Save
This paper gives two moment inequalities for σ-mixing and (ψ-mixing sequences. In the study of weighted sums, they are more useful than ones abtained by Shao Qiman in [6] and [7]. Here they are applied to discuss the rate of strong convergence for the nonparametric recursive kernel estimators and the strong consistency for the nonparametric weighted kernel estimators of regression function. The obtained results are much better.
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The Existence and Uniqueness of Periodic Solutions to Higher Dimensional Periodic System with Delay

JinDe Chao(1),YongKun Li(2)

Acta Mathematica Sinica, Chinese Series    1997, 40 (2): 280-286.   DOI: 10.12386/A1997sxxb0035
Abstract5021)      PDF(pc) (377KB)(767)       Save
In this paper, higher dimensional periodic systems with delay of the form x'(t) = A(t,x(t))x(t) + f(t,x(t - r)) are considered, where the n x n matrix A(t, x) and the n-vector f(t,x) are continuous in (t,x) ∈ R × Rn, and A(t + T,x)-A(t,x), f(t + T, x) = f(t, x). Using fixed point method, some sufficient conditions to guarantee the existence and uniqueness of T periodic solution for the systems are obtained. The main results in [1-3] are extended and improved.
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The Pointwise Continuity of the M-P Inverses A_x~+
WeiPing Chao(1),JiPu Ma(2)
Acta Mathematica Sinica, Chinese Series    1997, 40 (2): 287-295.   DOI: 10.12386/A1997sxxb0036
Abstract3389)      PDF(pc) (394KB)(733)       Save
We give some conditions of the pointwise continuity of the M-P inverses Ax+ of Ax, when Ax is pointwise continuous. Then some applications to integral equations are given in 3.
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Paracommutators on Local Fields
Jin Zou
Acta Mathematica Sinica, Chinese Series    1997, 40 (2): 296-300.   DOI: 10.12386/A1997sxxb0037
Abstract2642)      PDF(pc) (349KB)(768)       Save
The main result of this paper is: suppose that A(ζ,η) satisfies A0, A1, A2, A3, A4, then Tb is bounded on L2(K) if and only if b eBMO(K). We apply this result to prove that the commutator of fractional integration with b is bounded on L2(K) if and only if b∈I-s(BMO), (-1 < s < 0), the commutator of singular integral transform with b is bounded on L2(K) if and only if b∈BMO(K), and the commutator of multiplier with b is bounded on L2(K) if b∈BMO(K).
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Tensor Product of Modules and Indecomposables Module for Quantum Algebras
YuanHuai Bai
Acta Mathematica Sinica, Chinese Series    1997, 40 (2): 301-307.   DOI: 10.12386/A1997sxxb0038
Abstract2964)      PDF(pc) (450KB)(729)       Save
Let M be the ideal in Z[v] generated by v-1 and a odd prime p, U be a quantum algebra over A-Z[V]M with a symmetric Cartan matrix. Let k be algebraically closed field of characteristic zero. Consider a ring homomorphism A→k (v→ζ) and let Uk = U A k, Uk be infinitesimal quantum algebra of Uk,ζ be a primitive p-th root of 1. Let V and M be finite dimensional integrable Uk-modules. In this paper we show that Uk module isomorphisms V M ≌ M V when at least one of V or M is injective, or least one of V or M is trivial Uk module. Moreover, if V is indecomposable Uk module, M is indecomposable Uk module and M restricts to an indecomposable Uk module, then we show that V M is indecomposable Uk module. Finally, if V and M is Uk module isomorphisms and with unique simple submodule, we prove that the V and M also is Uk module isomorphisms, this shows Uk structure on indecomposable injective Uk module is unique.
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Group Rings over Lower Dimensional Rings
HuanYin Chen
Acta Mathematica Sinica, Chinese Series    1997, 40 (2): 308-312.   DOI: 10.12386/A1997sxxb0039
Abstract2521)      PDF(pc) (353KB)(764)       Save
In this paper, we study the structures of modules over group ring RG with KdimR ≤1, gl.dimR ≤ 2 or w.gl.dimR = 0. As applications, we give some characterizations of group rings with lower dimensional coefficient rings.
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A Note on Comparison Theorems for Splittings of Bounded Operators
YongZhong Song
Acta Mathematica Sinica, Chinese Series    1997, 40 (2): 313-318.   DOI: 10.12386/A1997sxxb0040
Abstract2944)      PDF(pc) (335KB)(748)       Save
Comparison theorems for nonnegative splittings of bounded linear operators have been presented by Marek and Szyld. Without detailed proofs, they also gave the hypotheses which provide strict inequalities for the comparisons. In this note, several counter examples are given which show that all the hypotheses by Marek and Szyld, which provide strict inequalities, are not sufficient. Then the corrected comparison theorems are proposed.
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