We investigate the temperature dependence of the order parameters of the Blume–Capel model for zero magnetic field in the lowest approximation of the cluster variation method which is identical to the mean-field approximation. Besides the stable branches of the order parameters, we establish...

The magnetic properties of the mixed spin-12 and spin-1 Ising ferromagnetic system with a crystal–field interaction in the absence and presence of an external magnetic field are studied by using the cluster variation method. Thermal variations of order parameters are investigated and the...

An interactive two-state model for cell membrane potassium and sodium ion channels in the presence of electric fields is proposed and studied using the pair approximation. In the model, ion channels which can either be in an open or closed states are regarded as residing on a two-dimensional...

A mixed-spin Ising model on a decorated Bethe lattice is rigorously solved by combining the decoration–iteration transformation with the method of exact recursion relations. Exact results for critical lines, compensation temperatures, total and sublattice magnetizations are obtained from a...

Using the exact recursion method, the magnetic properties (magnetizations, phase transition, tricritical point and compensation temperatures) of a ferrimagnetic mixed Ising bilayer system (σ=1/2 and S=1) with single-ion anisotropy are investigated. The influence of the single-ion anisotropy D...

A kinetic model of cell membrane ion channels is proposed based on the path integral method. From the Pauli-type master equations valid on a macroscopic time scale, we derive a first-order differential equation or the kinetic equation which governs temporal evolution of the channel system along...

The concept of a global phase diagram – a diagram in the space of fluid interaction parameters in which regions of similar types of phase behavior are demarcated – has proved very valuable in both theoretical and experimental studies of fluid mixtures. This type of work sheds light on the...

We investigate hierarchical structures of the European countries by using debt as a percentage of Gross Domestic Product (GDP) of the countries as they change over a certain period of time. We obtain the topological properties among the countries based on debt as a percentage of GDP of European...

We have examined the hierarchical structures of correlations networks among Turkey’s exports and imports by currencies for the 1996–2010 periods, using the concept of a minimal spanning tree (MST) and hierarchical tree (HT) which depend on the concept of ultrametricity. These trees are...

We studied the topology of correlation networks among 34 major currencies using the concept of a minimal spanning tree and hierarchical tree for the full years of 2007–2008 when major economic turbulence occurred. We used the USD (US Dollar) and the TL (Turkish Lira) as numeraires in which the...