Nonlinear and dynamic programming models for an inventory problem in a partially observable environment

Darendeliler, Alp
In this study, a single-item periodic-review inventory system is considered in a partially observable environment with finite capacity, random yield and Markov modulated demand and supply processes for finite-horizon. The exact state of the real process, which determines the distribution of the demand and supply, is unobservable so the decisions must be made according to the limited observations called observed process. Partially Observable Markov Decision Process is used to model this problem. As an alternative to the dynamic programming model, a nonlinear programming model is developed to find optimal policies. The optimal policies of the nonlinear program is more practical to obtain and use compared to the dynamic programming model. Computational study is performed for the three data sets in order to compare the results of the two models. The results show that the optimal policies of the two models are the same.


Tactical inventory and backorder decisions for systems with predictable production yield
Mart, Turgut; Duran, Serhan; Department of Industrial Engineering (2010)
We consider a manufacturing system with stochastic demand and predictable production yield. The manufacturer has predetermined prices and limited production capacity in each period. The producer also has the option to save some inventory for future periods even if there is demand in the current period. The demand that is not met is lost or may be backordered for only one period. Our objective is to maximize the expected profit by choosing optimal production, save and backorder quantities in each period. We ...
Energy preserving methods for lattice equations
Erdem, Özge; Karasözen, Bülent (2010-11-27)
Integral preserving methods, like the averaged vector field, discrete gradient and trapezoidal methods are to Poisson systems. Numerical experiments on the Volterra equations and integrable discretization of the nonlinear Schrodinger equation are presented.
Nonlinear Finite Element Analysis Versus Ex Vivo Strain Gauge Measurements on Immediately Loaded Implants
Eser, Atilim; AKÇA, KIVANÇ; Eckert, Steven; Cehreli, Murat Cavit (2009-05-01)
Purpose: To evaluate the level of agreement between nonlinear finite element stress analysis (NL-FEA) and ex vivo strain gauge analysis (EV-SGA) on immediately loaded implants. Materials and Methods: Four 4.1-mm-diameter, 12-mm-long implants were placed bilaterally into the lateral and first premolar regions of completely edentulous maxillae of four human cadavers. Two-element 90-degree rosette strain gauges were bonded to the labial cortical bone around the implants, and 100 N maximal load was applied over...
Computer Solutions of Plane Strain Axisymmetric Thermomechanical Problems
Eraslan, Ahmet Nedim (2005-08-01)
A simple computational model is developed to estimate elastic, elastic-plastic, fully plastic, and residual stress states in generalized plane strain axisymmetric structures considering temperature dependent physical properties as well as nonlinear isotropic strain hardening. Using the von Mises yield criterion, total deformation theory and a Swift-type nonlinear hardening law, a single nonlinear differential equation governing thermoelastoplastic behavior is obtained. A shooting technique using Newton iter...
Kalaylıoğlu Akyıldız, Zeynep Işıl; Ghosh, Sujit K. (2013-12-01)
A series of returns are often modeled using stochastic volatility models. Many observed financial series exhibit unit-root non-stationary behavior in the latent AR(1) volatility process and tests for a unit-root become necessary, especially when the error process of the returns is correlated with the error terms of the AR(1) process. In this paper, we develop a class of priors that assigns positive prior probability on the non-stationary region, employ credible interval for the test, and show that Markov Ch...
Citation Formats
A. Darendeliler, “Nonlinear and dynamic programming models for an inventory problem in a partially observable environment,” M.S. - Master of Science, Middle East Technical University, 2016.