IRANIAN JOURNAL OF SCIENCE AND TECHNOLOGY TRANSACTION A- SCIENCE
Year:2006 | Volume:30 | Issue:A2|Papers Count:11

Let G be a locally compact group, and let w be a weight on G. We show that the weighted measure algebra M(G, w) is amenable if and only if G is a discrete, amenable group and sup{w (g) w (g−1) :gÎG} < ¥ , where w (g)³1 (gÎG).

Scott and Szewczyk in Technometrics, 2001, have introduced a similarity measure for two densities ¦1 and  ¦2 , bySIM(¦1 ¦2)=< ¦1 ¦2>/Ö<¦1 ¦2> <¦1 ¦2>Where<¦1 ¦2>ò+¥-¥¦1(c,q1) ¦2(c,q2)dc sim(¦1 ¦2) has some appropriate properties that can be suitable measures for the similarity of ¦1 and ¦2 . However, due to some restrictions on the value of parameters and the kind of densities, discrete or continuous, it cannot be used in general. The purpose of this article is to give some other measures, based on modified Scott's measure, and Kullback information, which may be better than sim (¦1 ¦2) in some cases. The properties of these new measures are studied and some examples are provided.

In this paper the class of n-ary hypergroups is introduced and several properties are found and examples are presented. n-ary hypergroups are a generalization of hypergroups in the sense of Marty. On the other hand, we can consider n-ary hypergroups as a good generalization of n-ary groups. We define the fundamental relation b* on an n-ary hypergroup H as the smallest equivalence relation such that H / b* is the n-ary group, and then some related properties are investigated.

In the present paper, the sequence space ar(u, p) of a non-absolute type is introduced and it is proved that the space ar(u, p) is linearly isomorphic to the Maddox’s space (p).Besides this, the basis is constructed and the a-, b- and γ-duals are computed for the space ar(u, p). Furthermore, some matrix mappings from ar(u, p) to some sequence spaces are characterized. The final section of the paper is devoted to some consequences related to the rotundity of the space ar(u, p).

Finite and boundary element methods have been used by many authors to solve mathematical physics problems. However, the coupling of these two methods happens to be more efficient as it combines their merits. In this paper, the mathematical analysis of the coupling of finite and boundary element methods for the Helmholtz equation is presented.

A 2-D heat conduction model has been solved by using the Adomian Decomposition Method to predict the transient temperature and heat flux distribution in a thick solid that is irradiated by a laser source. The laser source may operate in a continuous wave (CW) mode or repeated pulse (RP) mode and may have arbitrary, spatial and temporal profiles.A generalized solution containing five-term approximation of a rapidly convergent series is obtained. The solution is then applied to some special cases of practical interest, such as laser irradiation of sandstones and limestones. Laser drilling of geologic formations is being considered by the petroleum industry in the foreseeable future. The 2-D transient temperature distribution is presented in a graphical form and discussed.A comparison between the results obtained from the Adomian method and those obtained numerically by using the Crank-Nicholson method is also presented.

In this paper, the stability and boundedness of solutions of a second order nonlinear vector differential equation are investigated. Our results include and improve some well-known results in the relevant literature.

We obtain sufficient conditions for the series Sanln to be absolutely summable of order k by a triangular matrix.

In the present paper we define strongly Dn -summable sequences which generalize A-summable sequences and prove such spaces to be complete paranormed spaces under certain conditions, some topological results have also been discussed.

In this paper, we obtain two intrinsic integral inequalities of Hessian manifolds.