@article{leca_kempf_uzsoy_2022, title={TOWARDS DECENTRALIZED DECISIONS FOR MANAGING PRODUCT TRANSITIONS IN SEMICONDUCTOR MANUFACTURING}, ISSN={["0891-7736"]}, DOI={10.1109/WSC57314.2022.10015337}, abstractNote={Continuous renewal of the product portfolio through product transitions is crucial to semiconductor manufacturing firms. These decisions take place in a decentralized environment, where decisions by different functional units must be coordinated to optimize corporate performance. Starting from a centralized optimization model, we obtain decentralized models using Lagrangian relaxation, and explore the challenges encountered in formulating and solving these decentralized models. Although the Lagrangian approaches yield tight upper bounds on the optimal solution value, the structure of the dual solution renders the construction of a near-optimal feasible solution difficult, and fully separable decentralized models encounter significant problems in achieving convergence due to scaling issues. We present computational experiments that illustrate the difficulties involved, and discuss directions for future work.}, journal={2022 WINTER SIMULATION CONFERENCE (WSC)}, author={Leca, Carlos and Kempf, Karl and Uzsoy, Reha}, year={2022}, pages={3442–3452} }
 @article{kravetz_leca_brito_saloni_tilotta_2020, title={Characterization of Selected Pyrolysis Products of Diseased Orange Wood}, volume={15}, ISSN={["1930-2126"]}, DOI={10.15376/biores.15.3.7118-7126}, abstractNote={Orange trees in Brazil are often burned as a means of eradication when they become infected with Huanglongbing disease. Rather than destroying them, which is a low-value proposition, one potential option is to utilize the biomass through pyrolysis. In this preliminary work, orange trees (Citrus sinensis) otherwise selected for purging, were sampled and pyrolyzed at 500 °C, and the charcoal and bio-oil were evaluated for potential value-added use. The results showed that the pyrolysis process resulted in 26.3% charcoal, 57.6% bio-oil, and 16.0% non-condensable gases. Qualitative analysis of the bio-oil by gas chromatography/mass spectrometry found 178 chemical compounds; however, only 25% of those compounds could be reliably identified. Potential applications of the compounds identified in the bio-oil were determined by examining the published literature, and it was found that at least 73% of them showed promise. Finally, initial studies on the immediate analysis of the pyrolysis charcoal showed that it potentially meets the standards set forth for Brazilian domestic use.}, number={3}, journal={BIORESOURCES}, author={Kravetz, Carolina and Leca, Carlos and Brito, Jose Otavio and Saloni, Daniel and Tilotta, David C.}, year={2020}, month={Aug}, pages={7118–7126} }