We study increasing quasiconcave functions which are co-radiant. Such functions have frequently been employed in microeconomic analysis. The study is carried out in the contemporary framework of abstract convexity and abstract concavity. Various properties of these functions are derived. In...

The control problem of controlling ruin probabilities by investments in a financial market is studied. The insurance business is described by the usual Cramer-Lundberg-type model and the risk driver of the financial market is a compound Poisson process. Conditions for investments to be...

Nonzero-sum ergodic semi-Markov games with Borel state spaces are studied. An equilibrium theorem is proved in the class of correlated stationary strategies using public randomization. Under some additivity assumption concerning the transition probabilities stationary Nash equilibria are also...

In this paper we analyze a single removable and unreliable server in the N policy M/G/1 queueing system in which the server breaks down according to a Poisson process and the repair time obeys an arbitrary distribution. The method of maximum entropy is used to develop the approximate...

In this paper we consider vector optimization problems where objective and constraints are set-valued maps. Optimality conditions in terms of Lagrange-multipliers for an ɛ-weak Pareto minimal point are established in the general case and in the case with nearly subconvexlike data. A comparison...

Order-value optimization (OVO) is a generalization of the minimax problem motivated by decision-making problems under uncertainty and by robust estimation. New optimality conditions for this nonsmooth optimization problem are derived. An equivalent mathematical programming problem with...

This paper gives conditions for the convergence of the Laurent series expansion for a class of continuous-time controlled Markov chains with possibly unbounded reward (or cost) rates and unbounded transition rates. That series is then used to study several optimization criteria, including...

The paper deals with a class of semi-Markov control models with Borel state and control spaces, possibly unbounded costs, and unknown holding times distribution H. Assuming that H does not depend on state-action pairs, we combine suitable methods of statistical estimation of H with control...

Brucker et al. (Math Methods Oper Res 56: 407–412, 2003) have given an O(n <Superscript>2</Superscript>)-time algorithm for the problems <InlineEquation ID="IEq1"> <EquationSource Format="TEX">$$P \mid p_{j}=1, r_{j}$$</EquationSource> </InlineEquation>, outtree <InlineEquation ID="IEq2"> <EquationSource Format="TEX">$$\mid \sum C_{j}$$</EquationSource> </InlineEquation> and <InlineEquation ID="IEq3"> <EquationSource Format="TEX">$$P \mid pmtn, p_{j}=1, r_{j}$$</EquationSource> </InlineEquation>, outtree <InlineEquation ID="IEq4"> <EquationSource Format="TEX">$$\mid \sum C_{j}$$</EquationSource> </InlineEquation>. In this note, we show that their algorithm admits an...</equationsource></inlineequation></equationsource></inlineequation></equationsource></inlineequation></equationsource></inlineequation></superscript>