data envelopment analysis (dea) is a wide range of mathematical models that used for measuring the relative efficiency of a set of harmonic units whit similar inputs and outputs. this model calculates some different weight for input and output variables in each decision making model. this variation in similar weights caused some critiques to this method. from 1991 some linear and nonlinear mode...

presence of distributed generation (dg) in electric distribution systems provides an attractive new alternative in capacity expansion planning of these systems. in this paper a new model is developed for solving simultaneous placement of hv/mv substations and dg units as a static planning tool. this model aims to minimize fixed and variable costs of planning. constraints related to dgs, substat...

the numerical methods are of great importance for approximating the solutions of nonlinear ordinary or partial differential equations, especially when the nonlinear differential equation under consideration faces difficulties in obtaining its exact solution. in this latter case, we usually resort to one of the efficient numerical methods. in this paper, the chebyshev collocation method is sugge...

in the present study an alternative model allows the extension of the debye-hückel theory (dht) considering time dependence explicitly. from the electro-quasistatic approach (eqs) done in earlier studies time dependent potentials are suitable to describe several phenomena especially conducting media as well as the behaviour of charged particles in arbitrary solutions acting as electrolytes.this...

The control of blood pressure is a complex mixture of neural, hormonal and intrinsic interactions at the level of the heart, kidney and blood vessels. While experimental approaches to understanding these interactions are useful, it remains difficult to conduct experiments to quantify these interactions as the number of parameters increases. Thus, modelling of such physiological systems can offe...

performance of a supply chain highly depends on its suppliers and therefore, appropriate selection of them is of great importance. this paper presents an integrated model of an mcdm method and a mathematical programming in order to select suppliers and determine lot sizes in the supply chain. the proposed framework comprises two main sub-models; the qualitative sub-model seeks to evaluate the s...

In this paper it is shown that the global existence in time and asymptotic profile of the solution of a mathematical model of tumour invasion with proliferation proposed by Chaplain et al. For this purpose we consider a related nonlinear evolution equation with strong dissipation and proliferation corresponding to our mathematical model and the initial Neumann-boundary value problem for the evo...

hysteretic dampers as the most practical passive control methods have improved the seismic performance of steel structures through energy dissipation induced by large inelastic deformations. among them in this paper, kbf (knee braced frames), a special form of braced frames having a diagonal brace connected to a knee element instead of beam-column joint, is investigated. in such systems, the kn...