Possibility Of Solving Research Articles

Codify a Three echelon inventory control model in terms of inflation with allowed shortage for a deterioration items

In this research initially, trying to find a model for inventory control system in a three-echelon supply chain for one-product system composed of levels of production, warehouse and seller and then will be trying to find optimal point in mentioned model. Model condition has been under inflation and has been considered for a commodity in which shortage is allowed and production has been deteriorating. With assumption be stable lead time and rate of demand and production and deterioration factor, obtain the overall cost function and restrictions for mentioned state. The impact of inflation with exponential function is on the price of units after that because of complex non-linear equation obtained, possibility of solving is impossible through classical methods. So we use MATLAB software for the numerical solution, sometime in numerical cases MATLAB can’t solve in routine time or can’t solve so we proposed the simulated annealing metaheuristic algorithm for these cases.

Frictionally Decaying Frontal Warm-Core Eddies

Purpose. The dynamics of nonstationary, nonlinear, axisymmetric, warm-core geophysical surface frontal vortices affected by Rayleigh friction is investigated semi-analytically using the nonlinear, nonstationary reduced-gravity shallow-water equations. The scope is to enlarge the number of known (semi)analytical solutions of nonstationary, nonlinear problems referring to geophysical problems and even to pave the way to their extension to broader geometries and/or velocity fields. Methods and Results. The used method to obtain the solutions is based on the decomposition of the original equations in a part expressing their prescribed spatial structure, so that they can be transformed into ordinary differential equations depending on time only. Based on that analytical procedure, the solutions are then found numerically. In this frame, it is found that vortices characterized by linear distributions of their radial velocity and arbitrary structures of their section and azimuthal velocity can be described exactly by a set of nonstationary, nonlinear coupled ordinary differential equations. The first-order problem (i. e., that describing vortices characterized by a linear azimuthal velocity field and a quadratic section) consists of a system of 4 differential equations, and each further order introduces in the system three additional ordinary differential equations and two algebraic equations. In order to illustrate the behavior of the nonstationary decaying vortices and to put them in the context of observed dynamics in the World Ocean, the system’s solution for the first-order and for the second-order problem is then obtained numerically using a Runge-Kutta method. The solutions demonstrate that inertial oscillations and an exponential attenuation dominate the vortex dynamics: expansions and shallowings, contractions and deepenings alternate during an exact inertial period while the vortex decays. The dependence of the vortex dissipation rate on its initial radius is found to be non-monotonic: it is higher for small and large radii. The possibility of solving (semi)analytically complex systems of differential equations representing observed physical phenomena is rare and very valuable. Conclusions. Our analysis adds realism to previous theoretical investigations on mesoscale vortices, represents an ideal tool for testing the accuracy of numerical models in simulating nonlinear, nonstationary frictional frontal phenomena in a rotating ocean, and paves the way to further extensions of (semi-) analytical solutions of hydrodynamical geophysical problems to more arbitrary forms and more complex density stratifications.

ПЛОСКИЙ АСИНХРОННЫЙ ЭЛЕКТРОПРИВОД ЖЕРНОВОЙ МЕЛЬНИЦЫ

In modern flour production, the preservation of all vitamins and minerals in it is relevant. Minerals and vitamins are stored in flour, ground from whole grains. In the stone mills, the grain is subjected to repeated exposure to the working surfaces of the millstones, as a result of which the flour contains a large percentage of the most important components of the grain. The stone mill’s drive should provide a low rotational speed of the mills (peripheral speed up to 10 m/sec.) and the possibility of smooth control of its speed and torque without reducing the performance of the mill. From this point of view, it is promising to use in the mill’s drive, instead of asynchronous motors, rotation with additional devices (gearboxes, belt drives, V-belt drives, etc.) of flat asynchronous electric drives. The article suggests possible variants of technical solutions for stone mills with flat electric drives. It was concluded that the use of a flat asynchronous motor in the mill’s drive allows not only smoothly adjusting the frequency and torque of the millstones, but also because of the presence of edge effects, to prevent flour sticking in the millstone working zone. Compiled with the possibility of solving by analytical methods a mathematical model of mill’s drive, based on a flat electric drives, taking into account the longitudinal edge effect, the strength of viscous (internal) and dry (external) friction. The mechanical characteristics of the drive were found when moving the flat electric drives inductors and the dependencies of the change in the mill productivity on the millstone rotation frequency when grinding various grains, changing the fill factor of the grinding zone and the gap between the millstones were obtained.

Responsabilidade Institucional: Globalidade, Cidadania e Transparência

Globality's informational revolution brought huge challenges and new professional demands. The ideological transparency of teaching institutions emerges as a possibility of solving and relieving tensions of the school's environment. The regimental reforms must be aligned to the school's outer and inner limits, especially regarding the boundaries of good faith and sociability. Thus, the concepts of tolerance, limits, norms and rules of living and education undergo a redefinition tension in face of the set of global transformations and their reflexes on the growing juridicization of the school environment. To accept this problem is a fundamental element to the understanding and restructuring of the school environment.

A Tangent Formula Derived from Patterson-Function Arguments. IV. The Solution of Difference Structures Directly from Superstructure Reflections

The possibility of solving by direct methods the difference structure δ of a superstructure using only the intensities of the superstructure reflections h is shown. The refinement of the phases Φ of the strong superstructure E values, which are normalized separately from the E values of the main or substructure reflections, is carried out maximizing the function Zδp′ = Σh(Eh − 〈Eh〉)Ch(Φ), where Ch(Φ) is the amplitude of the structure factor of δ3 expressed in terms of Φ. The maximization is performed with a new tangent formula that only differs from that given previously [Rius (1993). Acta Cryst. A49, 406–409] by an extra summation, i.e. the phase information is now derived from quartets and negative quintets instead of triplets and negative quartets. A preliminary test calculation demonstrates the capability of this tangent formula to solve the difference structure of the mineral wermlandite using only the measured superstructure intensities. Although more tests covering a variety of situations are still required to allow for a generalization, this result seems to confirm the viability of determining the internal structure of reconstructed surfaces by interpreting the corresponding three-dimensional difference Patterson function by direct methods. Access to this function is now possible, since, with the advent of intense synchrotron sources, not only in-plane intensity data but also the corresponding diffraction rods can be measured.

The Tolman-Reggeantitelephone paradox: Its solution by tachyon mechanics

The possibility of solving (at least « in micropliysics ») all the ordinary causal paradoxes devised for tachyons is not yet widely recognized; on the contrary, the effectiveness of the Stuckelberg-Feynman « switching principle » is often misunderstood. We want, therefore, to show in detail and rigorously how to solve the oldest causal paradox, originally proposed by Tolman, which is the kernel of so many further tachyon paradoxes. The key to the solution is a careful application oftachyon kinematics, which can be unambiguously derived from special relativity. A systematic, thorough analysis of all tachyon paradoxes is going to appear elsewhere.