Measurements of relaxed expiratory volume in one second (REV1.0) and forced inspiratory volume in one second (FIV1.0) were made on 50 subjects on two occasions to know the variability of these procedures in the individual subject. The mean coefficients of variation for REV1.0 and FIV1.0 were 6740' and 892%, respectively. The 95% confidence limit of difference between highest readings obtained o...

Forming Limit Diagrams are useful tools for evaluation of formability in the sheet metals. In this paper the effects of yield criteria on predictions of the right and left-hand sides of forming limit diagrams (FLDs) are investigated. In prediction of FLD, Hosford 1979, “Karafillis-Boyce” (K-B) and BBC2000 anisotropy yield functions have been applied. Whereas the prediction of FLD is based on th...

Let k be a field and let Q be a (finite) quiver. We fix a representation S with EndkQ S = k and Ext 1 kQ(S, S) = 0. In analogy to [3, Section 1] we consider the following subcategories of repk Q. Let M S be the full subcategory of all modules X with ExtkQ(S,X) = 0 such that, in addition, X has no direct summand which can be embedded into some direct sum of copies of S. Similarly, let MS be the ...

We study Farrell Nil-groups associated to a finite order automorphism of a ring R. We show that any such Farrell Nil-group is either trivial, or infinitely generated (as an abelian group). Building on this first result, we then show that any finite group that occurs in such a Farrell Nil-group occurs with infinite multiplicity. If the original finite group is a direct summand, then the countabl...

We discuss sharpness in the Hausdorff Young theorem for unimodular groups. First the functions on unimodular locally compact groups for which equality holds in the Hausdorff Young theorem are determined. Then it is shown that the Hausdorff Young theorem is not sharp on any unimodular group which contains the real Une as a direct summand, or any unimodular group which contains an Abelian normal ...

Let {Xn, n >= 1} be a strictly stationary sequence of negatively associated random variables, with common continuous and bounded distribution function F. In this paper, we consider the estimation of the two-dimensional distribution function of (X1,Xk+1) based on histogram type estimators as well as the estimation of the covariance function of the limit empirical process induced by the se...

It is proved in this paper that the maximum number of limit cycles of system { dx dt = y, dy dt = kx− (k + 1)x2 + x3 + (α + βx + γx2)y is equal to two in the finite plane, where k > 11+ √ 33 4 , 0 < | | 1, |α| + |β| + |γ| = 0. This is partial answer to the seventh question in [2], posed by Arnold.

Misunderstandings about the Concept of Limit among High School Seniors E. Reyhaani, Ph.D. Z. Sharifi M. Soltaani The concept of limit is one of the basic concepts in mathematics. As such, clear understanding of it is pre-requisite for learning many other concepts. However, many of high school students suffer from misunderstanding this basic concept. To identify and remedy these ...