Nonconvex perturbations of maximal monotone differential inclusions

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Electrowetting-Induced Oil Film Entrapment and Instability

We investigate the spreading at variable rate of a water drop on a smooth hydrophobic substrate in an ambient oil bath driven by electrowetting. We find that a thin film of oil is entrapped under the drop. Its thickness is described by an extension of the Landau-Levich law of dip coating that includes the electrostatic pressure contribution. Once trapped, the thin film becomes unstable under the competing effects of the electrostatic pressure and surface tension and dewets into microscopic droplets, in agreement with a linear stability analysis. Our results recommend electrowetting as an efficient experimental approach to the fundamental problem of dynamic wetting in the presence of a tunable substrate-liquid interaction

Dynamics of the Orthoglide parallel robot

Recursive matrix relations for kinematics and dynamics of the Orthoglide parallel robot having three concurrent prismatic actuators are established in this paper. These are arranged according to the Cartesian coordinate system with fixed orientation, which means that the actuating directions are normal to each other. Three identical legs connecting to the moving platform are located on three planes being perpendicular to each other too. Knowing the position and the translation motion of the platform, we develop the inverse kinematics problem and determine the position, velocity and acceleration of each element of the robot. Further, the principle of virtual work is used in the inverse dynamic problem. Some matrix equations offer iterative expressions and graphs for the input forces and the powers of the three actuators

Resonant nonlinear periodic problems with the scalar p-Laplacian and a nonsmooth potential

We study periodic problems driven by the scalar p-Laplacian with a nonsmooth potential. Using the nonsmooth critical point theory for locally Lipsctiz functions,we prove two existence theorems under conditions of resonance at infinity with respect to the first two eigenvalues of the negative scalar p-Laplacian with periodic boundary conditions.Universidade de Aveir

Three nontrivial solutions for the p-Laplacian Neumann problems with a concave nonlinearity near the origin

We consider a nonlinear Neumann problem driven by the p- Laplacian, with a right-hand side nonlinearity which is concave near the origin. Using variational techniques, combined with the method of upper-lower solutions and with Morse theory, we show that the problem has at least three nontrivial smooth solutions, two of which have a constant sign (one positive and one negative).FCTPOCI/MAT/55524/200

The particularities of the calculation and of the cost reduction in lignite production

In the market economy, the entities are, in an objective way, obliged to be preoccupied with the reduction of costs, taking into consideration the relationship of independence and indirect proportionality between the level of production costs and profit. The laws of competition oblige to the limitation of the waste channels, to the introduction of performant tehnological and tehnical solutions, to the systematic development of the work productivity. Because of this, we appreciated that is advisable that also in the extraction of lignite, we should determine a correct production cost, according to which should be possible the identification of the cost optimization possibilities. On the other hand, the effective cost of the lignite has a major importance because it represents the price which is registered in the accountancy, and, at the same time, through its size, concreted in stocks, it influences the total of the circulant actives and the net active, and the financial result of the exercise. These aspects can be arguments for the option of approaching this work’s theme, in which there are analised the following problems: the general structure and the particularities of the production cost in lignite extraction and the directions for the minimization of the effective production cost, including for the applying of the standard-cost method.lignite stocks, production costs, actual cost, standard cost, cost reduction.