Heisenberg群上一类左不变LPDO的局部基本解及局部可解性

In this paper it is proved that local fundamental solution exists in some space W^m(H_n) (m∈Z), if the left invariant differential operator on the Heisenberg group H_n satisfies certain condition. The main results are:l.Let L be a left invariant differential operator on H_n. If there exist R≥0, r,s∈R and operators {B_λ|λ∈Γ_R} ∈V^s(Γ_R, M^r) such that, for almost all λ∈Γ_R, B_λ is the right inverse of Ⅱ_λ(L), then there exists E∈W^m(H_n) (when m≥0 or m even) or E∈W^m-1(H_n) (when m<0 and odd) such that LE =δ(near the origie) Where m=min([r],-[2s]-n-2); 2. Let L(W,T) be of the form (3.1). If there exist R≥0 and r,s∈R such that when |λ|≥R,(?) and C_λ≥ C|λ|^x(C>0), then the same conclusion as above holds with m=min(-[2r]-n-2,[-2s]-n-2).     

导算子范数的一个估计

In this paper, a derivation δ_AB mapping into a ideal I of B(H) is considered, when A,B ∈B(H) and I is a norm ideal. If Ran(δ_AB)?I, let δ_AB:B(H)→I denote the induced operator and let λ be the scalar such that A- λ∈I, B-λ∈I, we estimate the norm of δ_AB as follows‖A-λ‖+‖B-λ‖≥‖δ_AB‖≥‖A- λ‖+‖B-λ‖ when W_N(A-λ)∩W_N(λ - B)≠?, where W_N(A- λ) denotes the normalized maximal numerical range and ‖A-λ‖ denotes the norm of A-λ∈I. In particular when I=C_p(lp, we prove that ‖δ_AB‖_p=‖A-λ‖_p+‖B-λ‖_p if and only if ‖A-λ‖=‖A-λ‖_p and W_N(A-λ)∩W_N(λ-B)≠?. At last, some examples show that the estimate as above is exact.     

正规算子和亚正规算子的一些特征

In this paper it is proved that if T is a bounded linear operator on a Hilbert space H and λ(?)c1(W(T)), where cl(W(T)) is the closure of W(T)={(Tx, x); x∈H, ‖x‖ =1}, then T is normal iff U_λ=(T-λ)^*-1 (T-λ) is hyponormal and T is hyponormal iff U_λ=(T-λ)^*-1 (T-λ) is normaliod.     

真同态像都是挠模的挠自由模

This paper is devoted to proving the following fact :Let G be a Gabriel topology, E an injective module cogenerating torsion theory (T, F) associated to G. N_G= (0≠M∈F|M/L∈T for every nonzero submodu-le L?M} . then, M∈N_G if and only if1) M is uniform,2) every nonzero homomorphism form M into M is injective,3) M is a quasi-essential submodule of E.At the same time, we proved that if a module M∈N_G then M, M_G∈N_G.Fi-nally, we considered critically compressible modules, under the assumption that Gabriel topology G is perfect.     

关于控制算子的若干注记

Let B(H) be the set of all bounded linear operators on a Hilbert space H. An operator T∈B(H) is called dominant if (T-λ)(T-λ)^*≤M_λ²(T-λ)^*(T-λ),?λ∈C.The numerical range of T is difined by W (T) = {(Tx, x): ‖x‖ = 1, x∈H}. In Section 1 some new characteristic of dominant operators are given. If C = AB - BA, we prove that O∈W(C)^- then A is a dominart or φ-quasihy ponor-mal. In Section 2 we prove that O∈σ_e(△_A^σ) if A is a dominant, where(?), we also prove that if A∈B(H) is a norm attaining Ф-quasihyponormal, then A has a non-trivial invariant subspace. In Section 3 we discuss the closeness of the range of bounded linear operator F_AB:X→AX-XB, and prove that R(δ_A)∩{A}′∩{Aⁿ}′=0, where δ_A:X→AX-XA.     

Fuzzy度量化——嵌入理论的一个应用

A fuzzy Pseudo-metric space is called fuzzy metric space iff it is sub-T₀ space. Suppose that (X,F) is a fuzzy topological space. Consider a relation ～between ordinary points of X: x～y iff for each λ≠0,x_λ∈y_λ and y_λ∈x_λ. The relation～is an equivalent relation. The corresponding fuzzy quotien space is a sub-T0 space and is called the associated sub-T₀ space of (X,F). in this paper, we establish the following theorem via fzzzy imbedding theory:Theorem Suppose that (X,F) is a fuzzy topological space with countable topological base. Then (1)(X,F) is fuzzy metrizable iff it is a fuzzy completely regular and sub-T₀ space.(2)(X,F) is a fuzzy completely regular space,then its associated sub-T₀ space is fuzzy metrizable.     

关于Cn空间有界域的一个解析不变量

The main results of the present paper are: For any bounded D in space Cⁿ, there is an analytic invariant λ(D)(≤1). If D is a transitive domain, then λ(D)<1 and k₀(D)=(λ(D))/(1-λ(D)), where k₀(D) is the Schwarz constant of domain D (cf[1]). And we have discussed the Characteristic properties of λ(D).     

赋范线性空间的第二对偶空间

Theorem. A mapping x^** of X^* into sealar field Φ is a linear functional if and only if there exists a μ∈ba(S) such that X^**(X^*)=∫_sx^*(s)μ(ds),x^*∈X^* Theorem. F∈ba(S.Σ)^* if and only if there exists a λ∈ba (T) (T is the closed unit sphere of the space B(S,Σ))such that F(μ)=∫(∫_st(s)μ(ds))λ(dt),μ∈ba(S,Σ).     

分数阶连续模与Fourier级数的绝对收敛

Let f∈L_2π and let(?) be its Fourier series. For any γ>0 , the continuity modulus of fractional order γ of f∈L_2π^p(p≥1) is defined by.     

关于非线性泛函的一个问题

Suppose that H is a Hilbert space, D is a convex closed set inis a functioal, f(x)=1/2‖x‖²-g(x). Suppose that the minimum of f(x) withrespect to D is attained at x₀∈D and f(x) has a bounded linear Gateaux differential at x₀. In this paper we prove that f(x₀) is a critical value of f(x) when and only when g′(x₀)∈I_D(x₀)={(1-λ)x₀+λy|y∈D.λ≥0}.     

关于集值系统x∈F(x,y),y∈G(x,y)解的存在性

Let (E, ‖·‖) be a uniformly convex Banach space, X a nonempty compact and convex subset of E. Let F be a closed mapping of X×X into 2^X, G a mapping of X×X into C(X). It is shown that if for any f∈C(X), x∈X, F(x,f(x)) is a closed and convex subset of X, and G(x,f(x)) is a continuous function and for any x,y₁,y₂∈X,H(x,G(x,y₁),G(x,y₂))≤‖y₁-y₂‖ then there exist X₀,y₀∈X such that X₀∈F(x₀,y₀) and y₀∈G(x₀, y₀).     

关于正规δθ-可加空间的逆极限

This paper proves the following results: Let X = lim← { Xσ,π^σρ，∧ },| ∧ | =λ, and every pro-jection πσ : X → Xσ be an open and onto mapping. (A) If X is λ-paracompact and every Xσ is normal and δθ-refinable, then X is normal and δθ-refinable; (B) If X is hereditarily λ-pamcompact and every Xσ is hereditarily normal and hereditarily δθ-refinable, then X is hereditarily normal and hereditarily δθ-refiable.     

Fixed Point Theorem of {a,b,c} Contraction and Nonexpansive Type Mappings in Weakly Cauchy Normed Spaces

Let C be a closed convex weakly Cauchy subset of a normed space X. Then we define a new {a,b,c} type nonexpansive and {a,b,c} type contraction mapping T from C into C. These types of mappings will be denoted respectively by {a,b,c}-ntype and {a,b,c}-ctype. We proved the following： 1. If T is {a,b,c}-ntype mapping, then inf{ ｜｜ T（x）-x｜｜ ：x C C} =0, accordingly T has a unique fixed point. Moreover, any sequence {Xn}n∈NN in C with limn→∞｜｜T（xn） - Xn｜｜ = 0 has a subsequence strongly convergent to the unique fixed point of T. 2. If T is {a,b,c}-ctype mapping, then T has a unique fixed point. Moreover, for any x∈C the sequence of iterates {Tn （x）}n∈N has subsequence strongly convergent to the unique fixed point of T. This paper extends and generalizes some of the results given in [2,4, 7] and [13].     

Λ-模的σ-子模的标准表示式

Let A be a commutative ring with unit element, and let M be a Λ-module and σ∈Hom_Λ (M, M). Then a non-empty subset N of M is called a σ-submodule of the Λ-module M, if (1) a-b∈N for all a, bg∈N, and (2) λσ(α)∈N and x-σ(x)∈N for all λ∈Λ, α∈N, x∈M. Let N be a σ-submodule of M. N is said to be a primary σ-submodule of the Λ-module M, if (1) N≠M, and (2) whenever λ∈Λ, x∈M and λσ(x) ∈N, then either x∈N or λ^kσ(M)?N for some positive integer h. This paper is intended to show (1) that if M satisfies maximal condition of σ-submodule, and K is a σ-submodule of M, then K is a finite intersection of primary σ-submodules, and (2) that the uniqueness on the normal expression of σ-submodule of the Λ-module. Also, some results of fractional module have been obtained.     

优序理论与平面分拆

Let λ∈N_0~k satisfying λ_1λ_2…λ_k for natural number set N_0. An orderideal λ determined by λ is defined to be {(i,j):1jλ_i,1ik}N~2. A planepartition (reverse) π of shape λ is an order- reversing (preserving) map from λto N-0. If P is any set of plane partitions, the generating function (abbrev.asGF) of P is the polynomial or fromal power series , where |π|denotethe weight of π. The enumeration theory of plane partitions is an active fieldof combinatorics. There are several approaches which have been successfully     

球面Schr?dinger算子的迹

Let S be a unit sphere in R³,Δ_θ,φ be the spherical Laplasian and q(θ,φ) be a continuous function on S. The following trace formulae are proved for the eigenvalues μ_n of L₀=-Δ_θ,φ and λ_n of L=L₀+q.     

On approximation properties of non-convolution type nonlinear integral operators

In the present paper we state some approximation theorems concerning pointwise convergence and its rate for a class of non-convolution type nonlinear integral operators of the form:Tλ (f;x) = B A Kλ (t,x, f (t))dt , x ∈< a,b >, λ∈Λ. In particular, we obtain the pointwise convergence and its rate at some characteristic points x0 of f as (x,λ ) → (x0,λ0) in L1 < A,B >, where < a,b > and < A,B > are is an arbitrary intervals in R, Λ is a non-empty set of indices with a topology and λ0 an accumulation point of Λ in this topology. The results of the present paper generalize several ones obtained previously in the papers [19]-[23].     

交一致连续偏序集

In this paper, as a generalization of uniform continuous posets, the concept of meet uniform continuous posets via uniform Scott sets is introduced. Properties and characterizations of meet uniform continuous posets are presented. The main results are:(1) A uniform complete poset L is meet uniform continuous iff ↑(U ∩↓ x) is a uniform Scott set for each x ∈ L and each uniform Scott set U;(2) A uniform complete poset L is meet uniform continuous iff for each∨∨x∈ L and each uniform subset S, one has x ∧S ={x ∧ s | s ∈ S}. In particular, a complete lattice L is meet uniform continuous iff L is a complete Heyting algebra;(3) A uniform complete poset is meet uniform continuous iff every principal ideal is meet uniform continuous iff all closed intervals are meet uniform continuous iff all principal filters are meet uniform continuous;(4) A uniform complete poset L is meet uniform continuous if L1 obtained by adjoining a top element1 to L is a complete Heyting algebra;(5) Finite products and images of uniform continuous projections of meet uniform continuous posets are still meet uniform continuous.     

A characterization of generalized derivations of JSL algebras

Let AlgL be a J-subspace lattice algebra on a Banach space X and M be an operator in AlgL. We prove that if δ : AlgL → B(X) is a linear mapping satisfying δ(AB) = δ(A)B + Aδ(B)for all A, B ∈ AlgL with AMB = 0, then δ is a generalized derivation. This result can be applied to atomic Boolean subspace lattice algebras and pentagon subspace lattice algebras.     

关于M1-空间的又一注记

In this note, we prove that, let f be a quasi-open, closed mapping from an M₁-space x onto a q-space (or a space of pointwise countable type) Y, then y is an M₁-space; which partially answers a classic problem. "Is the irreducible closed image of an M₁-space M₁?" (irreducible closed mapping→quasi-open mapping).