Continuing the work K. C. Das, I. Gutman, B. Furtula, On second geometric-arithmetic index of graphs, Iran. J. Math Chem., 1(2) (2010) 17-28, in this paper we present lower and upper bounds on the third geometric-arithmetic index GA3 and characterize the extremal graphs. Moreover, we give Nordhaus-Gaddum-type result for GA3.

Every integer n > 0 є N defines an increasing monotonic series of integers: n1, n2, ...nk, such that nk = nk +k(k-1)/2. We define as s(m) the number of such series that an integer m belongs to. We prove that there are infinite number of integers with s=1, all of the form 2 (they belong only to the series that they generate, not to any series generated by a smaller integer). We designate them as...

Interval arithmetic is arithmetic for continuous sets. Floating-point intervals are intervals of real numbers with floating-point bounds. Operations for intervals can be efficiently implemented. Hence, the time is ripe for standardization. In this paper we present an interval model that is mathematically sound and closed for the 4 basic operations. The model allows for exception free interval a...

in this paper, we introduce a satisfaction function (sf) to compare interval values on the basis oftseng and klein’s idea. the sf estimates the degree to which arithmetic comparisons between two intervalvalues are satisfied. then, we define two other functions called lower and upper sf based on the sf. weapply these functions in order to present a new interpretation of inequality constraints wi...

A method for ray casting implicit surfaces, defined with procedural noise models, is presented. The method is robust in that it is able to guarantee correct intersections at all image pixels and for all types of implicit surfaces. This robustness comes from the use of an affine arithmetic representation for the quantity that expresses the variation of the implicit function along a ray. Affine a...

dust can be produced by almost all production processes in portland cement factory. dust exposure potentially can affect respiratory function. but evidence for respiratory effect of cement dust exposure has not been conclusive. in this study we assessed effect of cement dust exposure on respiratory function in a cement production factory. a respiratory symptoms questionnaire was completed and p...