The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
This paper is devoted to the problem of optimal weather routing for transoceanic ship voyages. The goal of optimization is to reduce travel time and fuel consumptions. The optimal route is searched on the admissible set, which comprises routes satisfying all of the imposed static and dynamic constraints. The static constraints are represented mostly by coastal lines and shallow waters. The dynamic...
We consider two close ways of linearization for sublinear operator that takes compact convex values. The first way consists in a representation of given multioperator by the family of so called basis selectors that are single-valued linear bounded operators. The second way consists in linear extension of given multioperator from its values on some Hamel basis. Every of the ways above leads to its...
We use the payment schedule based approach to ensure stable cooperation in multistage games with vector payoffs. On the example of the Shapley value in multicriteria game it is shown that the irrational behavior proof condition and the balance condition may be incompatible. We design a recurrent payment schedule that satisfies such advantageous properties as the efficiency condition, non-negativity...
Many of ordinary differential equations one can reduce to the form of a polynomial differential system. One of the best methods for the numerical solution of such systems is the method of Taylor series. In this work we consider the Cauchy problem for the polynomial ODE system, and then — a theorem about the accuracy of its solutions by this method. In connection with this theorem, a special minimax...
Exhausters and coexhausters were proposed by V.F. Demyanov and is used for studying nonsmooth functions. These objects are families of convex compact sets in terms of which optimality conditions are described. This makes possible to construct effective optimization algorithms for nonsmooth problems. Exhausters and coexhausters are not uniquely defined. The smaller families the easier computations...
This paper addresses a nonconvex optimization problem with the cost function and inequality constraints given by d.c. functions. The original problem is reduced to a problem without inequality constraints by the exact penalization procedure. A special local search method for the penalized problem is developed, which is based, first, on the linearization procedure with respect to the basic nonconvexity...
New results in the field of stability of elastic systems with one-sided reinforcement are obtained. The stability problem of the rods, compressed by the longitudinal force, being in an elastic medium and deflections of which are limited by a rigid obstacle on the one hand is analytically solved. The influence of boundary conditions on the magnitude of the critical force is investigated.
The technique hereinafter referred to as “differentiation by iteration” can be used in the study of the rate of convergence of iterative methods. The area of its application is essentially extended to the set of non-differentiable functions by introducing a notuon of a half-derivatives.
We study a problem of stable cooperation on a single-product market where firms are in competitive relationship. Firms compete in quantities, but the maximum quantity of the product to be produced by any firm is bounded which is common knowledge. We assume that firms may cooperate forming coalitions, and the firms belonging to the same coalition choose their quantities to maximize the joint profit...
A commutative diagram that connects the basic objects of commutative algebra with the main objects of commutative analysis is constructed. Namely, with the help of five types of canonical embeddings we constructed a diagram between two sets of objects: Abelian semigroups — Abelian regular (cancellative) semigroups — Abelian groups, on the first hand, and convex cones — regular convex cones — linear...
Controllable systems are considered. Sufficient conditions for global null-controllability are obtained for a given set of admissible controls. The Lyapunov functions are used for analyzing the presence of an asymptotic stationary point in the system.
A.N. Tikhonov's approximate system of linear algebraic equations solution approach is extended to find a stable solution of a linear programming problem with an approximation of the coefficient matrix. This approach is formalized as the special case of a linear programming problem. Necessary and sufficient conditions for the existence of the solution of specified problem and the form of this solution...
The problem of estimating the state of a nonlinear dynamical system based on spline-approximation of functions is considered in the article. The resulted examples of use in the task of filtering and signal detection.
Bending of vertical beams with the SD-effect under a concentrated load at the end of the beam is discussed. To solve this problem, the Ilyushin model of perfect plasticity is used. The problem is solved analytically and numerically for the heavy vertical beam made out of A40X steel with SD-effect. The solutions for beams with weight and without weight are compared.
The motion of mechanical system consisting of carrier and load is considered. The carrier has a rectilinear channel for load motion. The channel axis is located at fixed angle to horizon in vertical plane containing the carrier trajectory. The carrier motion differential equations and necessary conditions of carrier motion from immobility state are obtained for a preset given load motion law. The...
The problem of suboptimal control in stochastic nonlinear dynamical systems based on the spline approximation of nonlinear functions is considered in this article.
Statistical analysis is widely used for problem solving in different fields. We present a research on Saint Petersburg morbidity rate. The aim of the work is to detect the heterogeneity in districts of the city with respect to morbidity rate, which was chosen as an indicator of population health. Methods of cluster analysis was utilized for grouping districts to homogeneous sets. Clustering can be...
The results of development, theoretical justification and experimental research of interior point algorithms for solving linear programming problems are presented in the article.
The operation schedule of an oceangoing ship is influenced by wave and wind disturbances, and is therefore weather routing. The work shows the goal of finding a safe and time-saving route by meteorological obtained based on modified genetic algorithm. By improving selection operator of genetic algorithm the author achieves the goal of finding the optimal route more quickly and precisely. In the cross...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.