带有乘右适当断面的右主投射半群(英文)

In this paper,the concept of right adequate transversals of rpp semigroups is introduced.We establish the structure of rpp semigroups with multiplicative right adequate transversals in terms of right normal bands and right adequate semigroups.In particular, some special cases are considered.     

On generalized inverse transversals

Let S be a regular semigroup, S° an inverse subsemigroup of S.S° is called a generalized inverse transversal of S, if V（x）∩S°≠Ф. In this paper, some properties of this kind of semigroups are discussed. In particular, a construction theorem is obtained which contains some recent results in the literature as its special cases.     

MM-Wave Band Transversal Filter with Improved Spurious Characteristics

A spurious-suppressed transversal filter using the multiple-coupled line is proposed. The frequency characteristics of the multiple-coupled line are analyzed in detail. In order to compare the performances, the novel spurious-suppressed transversal filter using triple-coupled half-wavelength directional couplers is designed at 30 GHz. The spurious-suppression characteristics of the proposed transversal filter are verified by the full wave analysis and the measurement. The spurious response of the fabricated filter is effectively suppressed and the large attenuation is obtained in the stopband.     

On the state of strength‐three covering arrays

A covering array of size N, strength t, degree k, and order υ is a k × N array on υ symbols in which every t × N subarray contains every possible t × 1 column at least once. We present explicit constructions, constructive upper bounds on the size of various covering arrays, and compare our results with those of a commercial product. Applications of covering arrays include software testing, drug screening, and data compression. © 2002 Wiley Periodicals, Inc. J Combin Designs 10: 217–238, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/jcd.10002     

Randomization of Sharkovskii-type theorems

We formulate an abstract scheme for the randomization of Shar- kovskii-type theorems via transformation to the deterministic case. In particular, Sharkovskii-type theorems for scalar differential equations can be randomized in this way. A random version of the standard Sharkovskii theorem is presented explicitly. Many remarks, comments and illustrating examples are supplied.

     

On Adequate Transversals

We consider adequate transversals of abundant semigroups and prove that, in a particular case, there is a natural embedding of an inverse transversal within a certain regular subsemigroup. We also introduce the concepts of simplistic, perfect, and quasi-adequate transversal and provide a number of interesting connections between these.     

λ-Automorphisms of a Riemannian Foliation II

In Pak (Ann. Global Anal. Geom.13 (1995), 281–288), the notion of -automorphisms of a harmonic Riemannian foliation was extended to a general Riemannian foliation. By applying the characterization obtained in Pak of a -automorphism to be transversal Killing, we here consider the problem that a transversal conformal or projective field is transversal Killing. A special condition, namely _{B B} = 0, is discussed.     

On left Hadamard transversals in non-solvable groups

Let G be a group of order 4n and t an involution of G. A 2n-subset R of G is called a left Hadamard transversal of G with respect to 〈t〉 if G=R〈t〉 and for some subsets S₁ and S₂ of G. Let H be a subgroup of G such that G=[G,G]H, t∈H, and t^G⊄H, where t^G is the conjugacy class of t and [G,G] is the commutator subgroup of G. In this article, we show that if R satisfies a condition , then R is a (2n,2,2n,n) relative difference set and one can construct a v×v integral matrix B such that BB^T=B^TB=(n/2)I, where v is a positive integer determined by H and t^G (see Theorem 2.6). Using this we show that there is no left Hadamard transversal R satisfying (*) in some simple groups.