We consider the problem of deciding whether a given rational function has a power series expansion with all its coefficients positive. Introducing an elementary transformation that preserves such positivity we are able to provide an elementary proof for the positivity of Szegö’s function 1 (1− x)(1− y)+ (1− y)(1− z)+ (1− z)(1− x) which has been at the historical root of this subject starting wi...

background: human body posture influences on his/her physiological functions. the purpose of this study was to investigate the effect of forward shoulder correction on pulmonary function of elementary female students. methods: subjects of this quasi-experimental research were two groups (n=20) of students with normal posture (np) and forward shoulder posture(fsp)  which is divided randomly into...

There exist local search landscapes where the evaluation function is an eigenfunction of the graph Laplacian that corresponds to the neighborhood structure of the search space. Problems that display this structure are called “Elementary Landscapes” and they have a number of special mathematical properties. The term “Quasi-elementary landscapes” is introduced to describe landscapes that are “alm...

The study of honest elementary degrees has its roots in subrecursion theory from the nineteen seventies. Some relevant papers are Meyer & Ritchie [12] and Machtey [9–11]. These papers deal with subrecursive function classes being generated by so-called honest functions where an honest function is defined relative to a subrecursive class S and a model of computation: a function f : N → N is hone...

We introduce a new notion of computable function on R and prove some basic properties. We give two applications, first a short proof of Yoshinaga’s theorem that periods are elementary (they are actually lower elementary). We also show that the lower elementary complex numbers form an algebraically closed field closed under exponentiation and some other special functions.

cognitive impairment may be a common even at the onset of multiple sclerosis (ms). in this case-control study, we tried to find out the probable relationship between homocysteine levels and cerebral atrophy or cognitive impairment in patients with multiple sclerosis. one hundred fifty six patients who had ms according to mcdonald diagnostic criteria were included in this study. patients’ age, g...

Consider combining several elementary detectors by the extreme decision rule of responding "no" only when all elementary detectors respond "no" and "yes" otherwise. The question raised is: Which psychometric functions for the detectors have the property that the resulting psychometric function is simply the original function displaced in the logarithm of the physical scale? The answer is p(I) =...

In this paper, we first give a characterization of sub-topical functions with respect to their lower level sets and epigraph. Next, by using two different classes of elementary functions, we present a characterization of sub-topical functions with respect to their polar functions, and investigate the relation between polar functions and support sets of this class of functions. Finally, we obtai...

Abstract: Fractional differentiation models have proven their usefulness in representing high dimensional systems with only few parameters. Generally, two elementary fractional functions are used in time-domain identification: Cole-Cole and Davidson-Cole functions. A third elementary function, called Havriliak-Negami, generalizes both previous ones and is particularly dedicated to dielectric sy...