Simulation of Demographic Change in Palestinian Territories

Mortality, birth rates and retirement play a major role in demographic changes. In most cases, mortality rates decreased in the past century without noticeable decrease in fertility rates, this leads to a significant increase in population growth. In many poor countries like Palestinian territories the number of births has fallen and the life expectancy increased. In this article we concentrate on measuring, analyzing and extrapolating the age structure in Palestine a few decades ago into future. A Fortran program has been designed and used for the simulation and analysis of our statistical data. This study of demographic change in Palestine has shown that Palestinians will have in future problems as the strongest age cohorts are the above-60-year olds. We therefore recommend the increase of both the retirement age and women employment.Comment: For Int. J. Mod. Phys. C 18, issue 11; 9 pages including figures and progra

Complete list of Darboux Integrable Chains of the form t1x=tx+d(t,t1)t_{1x}=t_x+d(t,t_1)

We study differential-difference equation of the form $$\frac{d}{dx}t(n+1,x)=f(t(n,x),t(n+1,x),\frac{d}{dx}t(n,x))$$ with unknown $t(n,x)$ depending on continuous and discrete variables $x$ and $n$. Equation of such kind is called Darboux integrable, if there exist two functions $F$ and $I$ of a finite number of arguments $x$, $\{t(n\pm k,x)\}_{k=-\infty}^\infty$, ${\frac{d^k}{dx^k}t(n,x)}_{k=1}^\infty$, such that $D_xF=0$ and $DI=I$, where $D_x$ is the operator of total differentiation with respect to $x$, and $D$ is the shift operator: $Dp(n)=p(n+1)$. Reformulation of Darboux integrability in terms of finiteness of two characteristic Lie algebras gives an effective tool for classification of integrable equations. The complete list of Darboux integrable equations is given in the case when the function $f$ is of the special form $f(u,v,w)=w+g(u,v)$

Magnetostatic surface waves on left-handed materials (LHM)

The nonlinear characteristics of magnetostatic surface waves at microwave frequencies in a layered structure of left-handed material film and a semi-infinite linear ferrite substrate have been investigated. The general dispersion relation is derived and analyzed numerically. It is found that it has two solutions for ω (k), one represents a physical solution and other unacceptable. The effects of the applied external magnetic field around the proposed region have also been examined

Nonlinear TE Electromagnetic Surface Waves in a Ferrite Layered Structure

Characteristics of TE electromagnetic surface waves propagating in a nonlinear dielectric film bounded by a ferrite cover are examined theoretically. A dispersion relation based on Jacobian Elliptic Functions is derived, which describes the behaviour of the nonreciprocal nonlinear waves. ) TE ( . ) Jacobian Function (

COLLISIONAL DRIFT WAVES OF A WEAKLY MAGNETIZED PLASMA

The two-fluid equations are used to derive a model of collisional drift waves for cylindrical magnetized plasmas. Both the radial electron temperature variation and the sheared BE о о× rotation in the plasmas have been taken into account. It is found that the presence of the BE о о× rotation leads to an important modification of the theory of drift waves derived by Sayasov Yu. S. and Aebischer HA (1988). The theory is applied to an experimental data of helium plasma using Runge-Kutta integration method. Our calculation shows that the temperature variation and the BE о о× rotation are important in the predictions of drift wave frequency and radial position of the maximum wave amplitude

Surface Electromagnetic Waves at a Single Interface of Superconductor and Left-Handed Materials

The wave propagation characteristics along the single interface of superconductor and left-handed materials are investigated theoretically. An expression for the complex permittivity of a superconductor is derived in the approximation of two-component plasma containing "normal" and "superconducting" electrons. Basic relations are obtained in the general case at temperatures T ≤ Tc where c T is the critical temperature. The frequency, the structure, and the temperature dependences of surface electromagnetic waves propagating along a single interface of a superconductor-left-handed material interface are computed, analyzed and discussed

Integrable discretizations of the sine-Gordon equation

The inverse scattering theory for the sine-Gordon equation discretized in space and both in space and time is considered.Comment: 18 pages, LaTeX2

Non-linear surface waves at a single interface of semimagnetic semiconductor–left handed materials (LHM)

The nonlinear characteristics of TE surface waves at microwave frequencies in a layered structure of non-linear semimagneticsemiconductor cover and left-handed material substrate have been investigated. Numerical analysis and derivation were carried out for the dispersion relation in its general form. The power flow has also been studied as a function of wave number for different frequencies and magnetic fields. It is shown that the proposed waveguide structure depends significantly on the operating wave frequency and can be efficiently controlled by varying the frequency

Towards the theory of integrable hyperbolic equations of third order

The examples are considered of integrable hyperbolic equations of third order with two independent variables. In particular, an equation is found which admits as evolutionary symmetries the Krichever--Novikov equation and the modified Landau--Lifshitz system. The problem of choice of dynamical variables for the hyperbolic equations is discussed.Comment: 22

Sensitivity of Left Handed Material Film-Superconductor Waveguide Sensors

The sensitivity of planar waveguide sensor containing dielectric, superconductor, and left-handed materials has been theoretically investigated. The proposed waveguide sensor in this study consists of a metamaterial film bounded by a dielectric cover and a superconductor substrate. The variation of the sensor sensitivity are found to be strongly depended on the metamaterial film, the film thickness and the temperature of the superconductor