Bool阵的逆阵

We give a characterization of a regular Boolean matrix and prove that AB = I Implies that BA = I, where A and B are Boolean matrices whose elements belong to a Boolean algebra of a set with more than two elements.     

关于Fuzzy Drazin子半群

本文引进了ＦｕｚｚｙＤｒａｚｉｎ子半群的概念,并讨论了它们的一些代数性质,改进并推广了［５］、［６］、［８］、［１０］及［１１］中的许多重要结果     

The use of jacobi's lemma in unimodularity theory

The paper applies Jacobi's fundamental result on minors of the adjoint matrix to obtain properties on determinants of unimodular matrices.     

Ultra‐Tough Inverse Artificial Nacre Based on Epoxy‐Graphene by Freeze‐Casting

Epoxy nanocomposites combining high toughness with advantageous functional properties are needed in many fields. However, fabricating high‐performance homogeneous epoxy nanocomposites with traditional methods remains a great challenge. Nacre with outstanding fracture toughness presents an ideal blueprint for the development of future epoxy nanocomposites. Now, high‐performance epoxy‐graphene layered nanocomposites were demonstrated with ultrahigh toughness and temperature‐sensing properties. These nanocomposites are composed of ca. 99 wt % organic epoxy, which is in contrast to the composition of natural nacre (ca. 96 wt % inorganic aragonite). These nanocomposites are named an inverse artificial nacre. The fracture toughness reaches about 4.2 times higher than that of pure epoxy. The electrical resistance is temperature‐sensitive and stable under various humidity conditions. This strategy opens an avenue for fabricating high‐performance epoxy nanocomposites with functional properties.     

Implicit representation of generalized variable upper bounds in linear programming

In certain linear programs, especially those derived from integer programs, large numbers of constraints may have very simple form. Examples are:x _ij 1 (simple upper bounds [SUB]), _i x _ij = 1 (generalized upper bounds [GUB]) andx _ij y _i (variable upper bounds [VUB]). A class of constraints called generalized VUB [GVUB] is introduced which includes GUB and VUB as special cases. Also introduced is a method for representing GVUB constraints implicitly within the mechanics of the simplex method.Research supported in part by the Mobil Oil Corporation.     

Some improvements for two-sided bounds on the inverse of diagonally dominant tridiagonal matrices

In this paper, we obtain lower and upper bounds for the entries of the inverses of diagonally dominant tridiagonal matrices. First of all we derive the bounds for off-diagonal elements of the inverse as a function of the diagonal ones, then we improve the two-sided bounds for the diagonal entries obtaining sharper lower and upper bounds for all the elements of the inverse.     

LEFT INVERSES AND RIGHT INVERSES OF A STRONG ENDOMORPHISM OF A GRAPH

1IntroductionConsiderableattelltionhasbeendevotedtotilesemigroupoftheelldomorphislllsofagraph,inparticular,thesemigroupofthestrongendomorpllisnasofagraph,seesurvey[1].Themainpurposeoftheseresearchesliesintheapplicatiollsofthealgebraictheoryofsendgroupstothetheoryofgraphs.ItiswellknowllthatoneofthemostimportantconceptsillselltigrouptheoryisGreen'srelations.In[2],thecharacterizatiollofGreen'srelationsonsEnd(G),themolloidofthestrongendomorphisnisofagrapllG.isgiven.LetSbeasemigroup.Thenotation…     

Implicit representation of generalized variable upper bounds using the elimination form of the inverse on secondary storage

A constraint of a linear program is called a generalized variable upper bound (GVUB) constraint, if the right-hand is nonnegative and each variable with a positive coefficient in the constraint does not have a nonzero coefficient in any other GVUB constraint. Schrage has shown how to handle GVUB constraints implicitly in the simplex-method. It is demonstrated in this paper that the Forrest-Tomlin data structure may be used for the inverse of the working basis, and it is discussed how to update this representation from iteration to iteration.     

On inverses of some permutation polynomials over finite fields of characteristic three

By using the piecewise method, Lagrange interpolation formula and Lucas' theorem, we determine explicit expressions of the inverses of a class of reversed Dickson permutation polynomials and some classes of generalized cyclotomic mapping permutation polynomials over finite fields of characteristic three.