this paper investigates the dynamics and stability properties of a discrete-time lotka-volterra type system. we first analyze stability of the fixed points and the existence of local bifurcations. our analysis shows the presence of rich variety of local bifurcations, namely, stable fixed points; in which population numbers remain constant, periodic cycles; in which population numbers oscillate amo...

in this paper, a novel approach for ranking fuzzy numbers based on the angle measure is introduced. several left and right spreads at each chosen levels of fuzzy numbers is used to determine center of mass points(cmps) and then, the angels between the cmps and the horizontal axis is calculated. the total angle is determined by averaging the computed angles and finally, the novel method is compa...

a modification of peng-robinson equation is described wherein in the parameter b is expressed as a linear function of temperature. the modified equation is then applied to a series of light hydrocarbons and refrigerants, and predicted values for vapor pressure, saturated vapor volume, saturated liquid volume and the heat of evaporation are compared with the corresponding experimental data. cons...

an analytical equation of state (eos) developed by ihm-song-mason (ism) has been applied tocalculate some thermophysical properties of molten polymers including poly (1-octene) (po), poly (vinylmethyl ether) (pvme), poly (vinyl chloride) (pvc), and poly (styrene) (ps). three temperature-dependentparameters of the ism eos have been determined based on the alternative scaling constants, dispersiv...

an analytical equation of state was applied to calculate the thermodynamic properties for argon.the equation of state is that of song and mason. it is based on a statistical-mechanical perturbationtheory of the hard convex bodies and can be written as fifth-order polynomial in the density. thereexist three temperature-dependent parameters: the second virial coefficient, an effective molecularvo...

in the present work, we have obtained the equation of state for neutron star matter considering the in uence of the ferromagnetic and antiferromagnetic spin state. we have also investigated the structure of neutron stars. according to our results, the spin asymmetry stiens the equation of state and leads to high mass for the neutron star.

In this work we investigate a class of admitting center maps on a metric space. We state and prove some fixed point and best proximity point theorems for them. We obtain some results and relevant examples. In particular, we show that if $X$ is a reflexive Banach space with the Opial condition and $T:Crightarrow X$ is a continuous admiting center map, then $T$ has a fixed point in $X.$ Also, we ...

effect of in order to test the memory state in patients with non-insulin dependent diabetes mellitus (niddm) after glycemic control, one-hundred patients referring to isfahan endocrine and metabolism research center were simply randomized. they were compared in point of memory state with one hundred cases as the control group. the wechsler memory scale test was utilized to evaluate the memory s...