We study the Cauchy problem for the Hamilton-Jacobi equation with a semi-concave initial condition. We prove an inequality between the two types of weak solutions emanating from such an initial condition (the variational and the viscosity solution). We also give conditions for an explicit semi-concave function to be a viscosity solution. These conditions generalize the entropy inequality charac...

Stationary quasi-P eikonal equations, stationary Hamilton-Jacobi equations, arise from the asymptotic approximation of anisotropic wave propagation. A paraxial formulation of the quasi-P eikonal equation results in a paraxial quasi-P eikonal equation, an evolution Hamilton-Jacobi equation in a preferred direction, which provides a fast and efficient way for computing viscosity solutions of quas...

In this work, the ability of the MgCaFe- Layered double hydroxide (LDH) for congo red (CR) dye removal in aqueous solution was investigated. Various parameters such as initial dye concentrations, temperature, adsorbent dosage, pH effect and agitation rate were examined and optimal conditions (10 mgL-1 of the dye concentration, 25 °C of temperature, 0.5 gL-1 of the adsorbent dosage, pH~7 and 450...

The power supply of remote sites and applications at minimal cost and with low emissions is an important issue when discussing future energy concepts. This paper presents modeling and optimization of a photovoltaic (PV)/wind/diesel system with batteries storage for electrification to an off-grid remote area located in Rafsanjan, Iran. For this location, different hybrid systems are studied and ...

in this research, rice husk and activated carbon adsorbents were used for removal of lead ion from aqueous solution at ph= 6. in the batch tests experimental parameters were studied, including contact time and initial metal ions concentration.survey of the equilibrium time at different concentration showed that equilibrium time is reduced with decrease of initial concentration of solution from ...

background and purpose: recently, release of pollutants such as heavy metal ions to the environment becomes one of the most important problems for soil and water. the present study was conducted to introduce modified rice husk (rh) as a new low-cost adsorbent. materials and methods: in this study, tartaric acid modified rh (tarh), was used as an adsorbent for removal of ni(ii) and cd(ii) from w...

Light-emitting dendrimers are a new distinct class of material for OLEDs. Dendrimers consist of a light-emitting core, dendrons and surface groups. Dendrimers are designed for solution coating and have a number of advantages over conjugated polymers. We report our recent results for solution processed green dendrimer OLEDs. The OLEDs were fabricated by spin-coating a blend of first generation d...

The reload cost spanning tree problem (RCSTP) is an NP-hard problem, where we are given a set of nonnegative pairwise demands between nodes, each edge is colored and a reload cost is incurred when a color change occurs on the path between a pair of demand nodes. The goal is to find a spanning tree with minimum reload cost. We propose a tree-nontree edge swap neighborhood for the RCSTP and an ef...

We present efficient algorithms for solving Legendre equations over Q (equivalently, for finding rational points on rational conics) and parametrizing all solutions. Unlike existing algorithms, no integer factorization is required, provided that the prime factors of the discriminant are known.

The modeling of physical systems often leads to partial differential equations (PDEs). Usually, the equations or the domain where the equations are posed are so complicated that the analytic solution cannot be found. Thus, the equations must be solved using numerical methods. In order to do this, the PDEs are first discretized using the finite element method (FEM) or the finite difference metho...