The Least Distributive Lattice Congruence on Commutative Distributive Semiring

In this paper, we describe the least distributive lattice congruence on a commutative distributive semiring.

Exact Sequence and Commutative Diagrams of Semimodule Homomorphism

Throught the introduction of the concept * exact sequence,we set up several satisfied results of commutative diagrams of semimodule homomorphism.

An Extra Phase for Two-Mode Coherent States Displaced in Noncommutative Phase Space

Using deformed boson algebra,we study the property of two-mode coherent states in noncommutative phase space.When a two-mode field evolves in the noncommutative phase space,it can acquire an extra θ-dependent phase compared to the case of commutative space.This phase is detectable and may be used to test noncommutativity.

A TTP-Independent Watermarking Protocol Based on Commutative Cryptosystem for Copyright Protection in E-Commerce

For the purpose of deterring unauthorized duplication and distribution of multimedia contents in e-commerce, some Buyer-seller watermarking protocols which combine of traditional watermarking and fingerprinting techniques have been proposed, However, previous protocols have potential risk from trust third party （TTP） because all entities （including multi-buyers and multi-sellers） mentioned in protocol construct a star tupology like connection, in which the watermark certification authority （WCA） serves as the central point in the interaction and therefore its availability probably turns out to be the vital bottleneck of reliability and efficiency to the whole system. Secondly, WCA holds entire information about watermark used hy Buyers so that an innocent Buyer can he found as guilty if WCA collude with the Seller. In this paper, we propose a watermarking protocol to address the problems using cryptographic technologies in phase of watermark generation. The resuh is a TTP-independent and collusion-secure buyer-seller watermarking protocol.

The Energy Distribution of a Noncommutative Reissner–Nordström Black Hole

We study the energy distribution of a noncommutative Reissner–Nordström black hole.We consider both Ein-stein and Møller prescriptions,and compare our results with the corresponding results obtained recently for a Schwarzschild black hole.

An involutive Jordan automorphism of triangular matrix algebra over commutative rings

Let Tn＋1 （R） be upper matrix algebra of order n ＋ 1 over a 2-torsion free commutative ring R with identity. In this paper, we find an automorphism, which is fixed by all orthogonal idempotents and is not an R-algebra aulomorphism, of Tn＋1 （R）. Furthermore we prove that this aulomorphism is an involutive Jordan automorphism of Tn＋1 （R）.

FINITELY GENERATED COMMUTATIVE ARCHIMEDEAN SEMIGROUPS

In this work commutative Archimedean finitely generated semigroups axe characterized in terms of ideal extensions.

Ideals of Classical Linear Lie Superalgebra P(n) over Commutative Rings

Let R be a commutative ring with identity 1. The relations between the ideals of Lie superalgebra P（n） and the ideals of R are discussed by studying the basis, center and order ideal of P（n）. All ideals of P（n） are proved to be minimal and standard.

The Localization of Commutative Bounded BCK-Algebras

In this paper we develop a theory of localization for bounded commutative BCK-algebras. We try to extend some results from the case of commutative Hilbert algebras (see [1]) to the case of commutative BCK-alge- bras.

The K_2-groups over Finaite Commutative Rings

The present note determines the structure of the K2-group and of its subgroup over a finite commutative ring R by considering relations between R andfinite commutative local ring Ri (1 < i < m), where R Ri and K2(R) =K2(Ri). We show that if charKi= p (Ki denotes the residual field of Ri), then K2(Ri) and its subgroups must be p-groups.

On Commutative Δ-Semigroups

In this paper entitled on commutative Delta-Semigroups, we have obtained important results on commutative Δ-semigroups.

Derivations of Certain Lie Algebras of Upper Triangular Matrices over Commutative Rings

Let R be an arbitrary commutative ring with identity. Denote by t the Lie algebra over R consisting of all upper triangular n by n matrices and let b be the Lie subalgebra of t consisting of all matrices of trace 0. The aim of this paper is to give an explicit description of the derivation algebras of the Lie algebras t and b, respectively.

Quantum commutative algebras and their duals

If an algebra A is quantum commutative with respect to the action of a quasitriangular Hopf algebra H, then the monoidal structure on the category HM of modules over H induces a monoidal structure on the category A#H M modules over the associated smash product A #H. The condition under which the braiding structure of HM induces a braiding structure on A#H M is further investigated. Dually, the notion of quantum cocommutativity is introduced, and similar result in this dual situation is obtained

Computation of the Orders of Classical Groups Over Finite Commutative Rings

In the present note, we compute the orders of several classes of classical groups over finite commutative rings. Simultaneously, using the order of GL_n, we obtain some Anzahl theorems of vector space over local rings. For any finite commutative ring R (with identity 1), R can be written as a direct product of a finite number of local rings R_i, i.e. , where R_i is a local ring, and the classical group G(R) can be written as . So to determine the cardinality |G(R)|, we must determine |G(R_i)| the cardinality of classical group G over a local ring.

Jordan Higher Derivable Maps on Triangular Algebras by Commutative Zero Products

In this paper, the structure of Jordan higher derivable maps on triangular algebras by commutative zero products is given. As an application, the form of Jordan higher derivable maps of nest algebras by commutative zero products is obtained.

The nonexistence of sensitive commutative group actions on graphs

In this paper,we observe a special kind of continuous functions on graphs.By estimating the integrals of these functions,we prove that there are no sensitive commutative group actions on graphs.Furthermore,we consider a 1-dimensional continuum composed of a spiral curve and a circle and show that there exist sensitive homeomorphisms on it,which answers negatively a question proposed by Kato in 1993.

On Polynomial Functions over Finite Commutative Rings

Let R be an arbitrary finite commutative local ring. In this paper, we obtain a necessary and sufficient condition for a function over R to be a polynomial function. Before this paper, necessary and sufficient conditions for a function to be a polynomial function over some special finite commutative local rings were obtained.

Commutative Rings Whose Zero-divisor Graph Is a Proper Refinement of a Star Graph

A graph is called a proper refinement of a star graph if it is a refinement of a star graph, but it is neither a star graph nor a complete graph. For a refinement of a star graph G with center c, let G＊ be the subgraph of G induced on the vertex set V（G） ／ {c or end vertices adjacent to c}. In this paper, we study the isomorphic classification of some finite commutative local rings R by investigating their zero-divisor graphs G=Г（R）, which is a proper refinement of a star graph with exactly one center c. We determine all finite commutative local rings R such that G＊ has at least two connected components. We prove that the diameter of the induced graph G＊ is two if Z（R）2 ≠{0}, Z（R）3 = {0} and Gc is connected. We determine the structure of R which has two distinct nonadjacent vertices a, fl C Z（R）＊／{c} such that the ideal [N（a）N（β）]{0} is generated by only one element of Z（R）＊／{c}. We also completely determine the correspondence between commutative rings and finite complete graphs Kn with some end vertices adjacent to a single vertex of Kn.

THE STRUCTURE OF SYMPLECTIC GROUPS OVER ARBITRARY COMMUTATIVE RINGS

The structure of symplectic groups over fields has been determined completely. Several authors discussed symplectic groups over commutative rings, but they made strong restrictions on the underlying rings. In this letter we start from elementary symplectic matrices and,

THE STRUCTURE OF ORTHOGONAL GROUPS OVER ARBITRARY COMMUTATIVE RINGS

Let R be an arbitrary commutative ring, and n an integer≥3. It is proved for any ideal J of R thatEO2n（R, J）=[EO2n（R）, EO2n（J）]=[EO2n（R）, EO2n（R, J）]=[EO2n（R）, O2n（R,J）]=[O2n（R）, EO2n（R,J）].In particular, EO2n（R, J） is a normal subgroupof O2n（R）. Furthermore, the problem of normal subgroups of O2n（R） has an affirmative solution if and only if aR∩ Ann（2）=α2 Ann（2） for each a in R. In particular, if 2 is not a zero divisor in R, then the problem of normal subgroups of O2n（R） has an affirmative