A stochastic optimization approach for paper recycling reverse logistics network design under uncertainty

One of the most important objectives of a manufacturing firm is the efficient design and operation of its supply chain to maximize profit. Paper is an example of a valuable material that can be recycled and recovered. Uncertainty is one of the characteristics of the real world. The methods that cope with uncertainty help researchers get realistic results. In this study, a two-stage stochastic programing model is proposed to determine a long term strategy including optimal facility locations and optimal flow amounts for large scale reverse supply chain network design problem under uncertainty. This network design problem includes optimal recycling and collection center locations and optimal flow amounts between the nodes in the multi-facility environment. Proposed model is suitable for recycling/manufacturing type of systems in reverse supply chain. All deterministic, stochastic models are mixed-integer programing models and are solved by commercial software GAMS 21.6/CPLEX 9.0

Potential savings in buildings using stand-alone PV systems

This research analyses the electricity consumption and CO2 emissions of 3 hotels in Greece using energy auditing. Following this analysis, the energy generation, at the same month, from a stand alone PV system will be presented for each case, showing its contribution in electricity consumption and its possible share on the total electricity consumption. The PV systems are installed from the same company, and they have different power capacity of 75, 100 and 200kW. This research aims at showing potential energy and emissions savings from the selected cases, showing the necessity to promote the application of renewable energy sources and in particular PV stand alone systems in Greek hotels considering the current socio-economic situation of the country. © Springer-Verlag Berlin Heidelberg 2013