جستجوی مقالات مرتبط با کلیدواژه « Reduction » در نشریات گروه « ریاضی »

‎In this paper, the Lie symmetry method and Lie brackets of vector fields are used in order to find some new solutions of the (3+1)-dimensional sourceless wave equation‎. ‎The obtained solutions are classified into two categories; polynomial and non-polynomial exact solutions‎. ‎Because of the properties of the Lie brackets and the symmetries‎, ‎a generalized method is implemented for constructing new solutions from old solutions‎. ‎We demonstrate the generation of such polynomial and non-polynomial solutions through the medium of the group theoretical properties of the equation‎. ‎It is noteworthy that this method could be used when the equations have two special kinds of symmetries which will be mentioned below‎.

In this paper, we show that for any BL-general L-fuzzy automaton (BL-GLFA) there exists a complete deterministic accessible reduced BL-general L-fuzzy automaton that recognizing the behavior of the BL-GLFA. Also, we prove that for any finite realization β, there exists a minimal complete deterministic BL-GLFA recognizing β. We prove any complete deterministic accessible reduced BL-GLFA is a minimal BLGLFA. After that, we show that for any given finite realization β, the minimal complete deterministic BL-GLFA recognizing β is isomorphic to any complete accessible deterministic reduced BL-GLFA recognizing β. Moreover, we give some examples to clarify these notions. Finally, by using these notions, we give some theorems and algorithms and obtain some related results.

Herein, a highly efficient, simple, base-free, chemoselective and environmentally-benign strategy was developed for the reduction of nitro compounds using NaBH4 as a hydrogen and electron source in the presence of a bimetallic and low-cost nanocatalyst (Fe3O4@Ni-Co-BTC NPs). Thanks to inimitable structure of Fe3O4@Ni-Co-BTC NPs, this nanostructured catalyst exhibits superior catalytic performance for the reduction of a wide library of electron-donating and electron-withdrawing aromatic, heteroaromatic, heterocyclic and aliphatic nitro compounds. Interestingly, the aforesaid nanocatalyst showed high reactivity and chemoselectivity for the reduction of the nitro group in the presence of other reducible functional groups such as COOH, CHO, COCH3, CN, NHAc and OCOCH3. Furthermore, due to the superparamagnetic nature of Fe3O4@Ni-Co-BTC NPs, it could be easily separated from the reaction mixture and reused for at least seven consecutive recycle runs while its activity and selectivity was preserved. Performing the reaction at room temperature and in a green media is another notable feature of the present method.

Throughout this paper, all rings are commutative  with identity and all modules are unital. Let $R$  be a ring and $M$ be an $R$-module. Then $M$ is called a multiplication module provided for every submodule $N$ of $M$ there exists an ideal $I$ of $R$ such that $N=IM$. Also $M$ is said to be a comultiplication module if for every submodule $N$ of $M$ there exists an ideal $I$ of $R$ such that $ N=(0:_MI)$. In this  paper, we introduce the notions of reduction and coreduction of submodules, integral dependence, integral codependence, integral closure and $\Delta$-closure over multiplication and comultiplication modules.

The moment map is a mathematical expression of the concept of the conservation associated with the symmetries of a Hamiltonian system. The abstract moment map is defined from G-manifold M to dual Lie algebra of G. We will interested study maps from G-manifold M to spaces that are more general than dual Lie algebra of G. These maps help us to reduce the dimension of a manifold much more.

Among a wide range of pollutants, organic pollutants have given rise to major environmental concerns. Various methods have been considered to mitigate the damage, including catalytic reduction to less hazardous compounds. Catalysts that benefit from high surface area and suitable surface sites for various steps of the catalytic reaction have shown outstanding results in performing such duties. Mesoporous CuO/SiO2 has been synthesized and characterized here and it showed excellent results for catalytic removal of methylene blue as a model organic pollutant. Several control samples were also studied to postulate a possible mechanism for activity enhancement.

This paper introduces the notion of multidimensional fuzzy finite tree automata (MFFTA) and investigates its closure properties from the area of automata and language theory. MFFTA are a superclass of fuzzy tree automata whose behavior is generalized to adapt to multidimensional fuzzy sets. An MFFTA recognizes a multidimensional fuzzy tree language which is a regular tree language so that for each dimension, a fuzzy membership grade is assigned to each tree. We study MFFTA by extending some classical problems and properties of automata and regular languages such as determinization, reduction, duality and operations on languages. Furthermore, we provided the method of converting every complete fuzzy tree automata to an MFFTA as well as an example to show the efficiency of MFFTA in comparison to FFTA.}

In this note, we define bisimulation for BL-general fuzzy automata and show that if there is a bisimulation between two BL-general fuzzy automata, then they have the same behavior.
For a given BL-general fuzzy automata, we obtain the greatest bisimulation for the BL-general fuzzy automata. Thereafter, if we use the greatest bisimulation, then we obtain a quotient BL-general fuzzy automata and this quotient is minimal, furthermore there is a morphism from the first one to its quotient.
Also, for two given BL-general fuzzy automata we present an algorithm, which determines bisimulation between them.
Finally, we present some examples to clarify these new notions.

In this paper we define a new type of rings”almost powerhermitian rings” (a generalization of almost hermitian rings) and establish several sufficient conditions over a ring R such that, every regular matrix admits a diagonal power-reduction.