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The design of distribution networks that simultaneously consider location and inventory decisions seeks to balance costs and product availability. The most commonly observed measure of product availability in practical settings is the fill‐rate service level. However, the optimal design of a distribution network that considers the fill rate to control shortages of fast‐moving consumer goods (FMCG) is considered intractable and has only been addressed by heuristic methods. This paper addresses the optimal design of a distribution network for FMCG able to provide high fill‐rate service level under a continuous review (r,Q)$(r,Q)$ policy. Considering the exact formulation for the provided fill rate, we formulated a joint location–inventory model with fill‐rate service level constraints as a convex mixed integer nonlinear problem for which a novel decomposition‐based outer approximation algorithm is proposed. Numerical experiments have shown that our solution approach provides good‐quality solutions that are on average 0.15% and, at worst, 2.2% from the optimal solution. [ABSTRACT FROM AUTHOR]

This paper studies carbon tax effectiveness in inducing a transition to cleaner production when a firm faces different technologies and demands over a planning horizon. To determine carbon tax effectiveness, we propose a model based on strategic capacity production planning under carbon taxes that considers proper performance measures. The model, which is formulated as a mixed integer linear problem (MILP), considers issues that previous works have not studied jointly, and that are relevant in a technological transition, such as machine replacement, workforce planning, and maintenance. The effectiveness measures consider levels of clean production and periods to reach a technological transition. Our computational experiments, based on a real case, have shown that in the absence of carbon taxes, a firm has no incentive to transition to clean technology. Still, the effectiveness of carbon taxes depends on the characteristics of the technology available for the production process and the magnitude of the demand. We include managerial insights aimed at both companies and the environmental authority. [ABSTRACT FROM AUTHOR]

This study aimed to determine the effect of CO2 laser microperforation (LMP) pre-treatment in terms of pore density and pore size on the time required for apple (Granny Smith) slices to reach a water activity below 0.4 by means of different dehydration techniques: osmotically dehydration followed by conventional hot air-drying (OD/CD) or refractance window™ technology (OD/RW™) or just drying by means of refractance window™ technology (RW™). Furthermore, a suitable mathematical model for the diffusion phenomenon was implemented. CO2 laser microperforation was performed on the apple slices in order to reach different pore radius and densities. Apple slices were osmotically dehydrated with a 45°Brix solution at 40 °C before the conventional and refractance window™ treatments, and others were directly dried with a RW™. The drying procedures were performed at 70 °C to reach a water activity (aw) below of 0.4. The drying time, color change, soluble solid content, and diffusion coefficients (Deff) were determined. Compared to non-microperforated samples, increasing the pores density from 2.86 to 7.94 pores/cm2 and the pores size from 100 to 300 μm, drying time was reduced in the range of 10 to 60%. The Deff ranged from 5.76 × 10–10 to 11.07 × 10–10 m2/s for the Fick's second law model and from 0.21 × 10–10 to 5.94 × 10–10 m2/sα for the anomalous diffusion model and showed super-diffusive behavior (α > 1). Laser pre-treatment favored anomalous diffusion behavior during drying. Collectively, RW™ showed promising results by significantly reducing the control drying time by over 50%. [ABSTRACT FROM AUTHOR]

Popular measures of product availability in inventory systems seek to control different aspects of stock shortages. However, none of them simultaneously control all aspects of shortages, because stock shortages in inventory systems are complex random events. This paper analyzes the performance of αL service measure, defined as the probability that stockouts do not occur during a replenishment cycle, to cover different aspects of stock shortages when used to design an optimal continuous review (Q, r) policy. We show that explicitly controlling the frequency of replenishment cycle stockouts, using the αL service-level, allows to implicitly control the size of the stockouts at an arbitrary time, the size of accumulated backorders at an arbitrary time, and the duration of the replenishment cycle stockouts. However, the cost of controlling the frequency of replenishment cycle stockouts is greater than the cost of controlling the size of stockouts and the duration of the replenishment cycle stockouts. [ABSTRACT FROM AUTHOR]