Optimization models for the dynamic facility location and allocation problem

International audienceThe design of logistic distribution systems is one of the most critical and strategic issues in industrial facility management. The aim of this study is to develop and apply innovative mixed integer programming optimization models to design and manage dynamic (i.e. multi-period) multi-stage and multi-commodity location-allocation problems (LAP). LAP belong to the NP-hard complexity class of decision problems, and the generic occurrence requires simultaneous determination of the number of logistic facilities (e.g. production plants, warehousing systems, distribution centers), their locations, and assignment of customer demand to them. The proposed models use a mixed integer linear programming solver to find solutions in complex industrial applications even when several entities are involved (production plants, distribution centers, customers, etc.). Lastly, an application of the proposed models to a significant case study is presented and discussed

Advanced head and neck surgery training during the COVID-19 pandemic

The COVID-19 pandemic has significantly impacted medical training. Here we assess its effect on head and neck surgical education. Methods Surveys were sent to current accredited program directors and trainees to assess the impact of COVID-19 on the fellow's experience and employment search. Current fellows' operative logs were compared with those of the 2018 to 2019 graduates. Results Despite reduction in operative volume, 82% of current American Head and Neck Society fellows have reached the number of major surgical operations to support certification. When surveyed, 86% of program directors deemed their fellow ready to enter practice. The majority of fellows felt prepared to practice ablative (96%), and microvascular surgery (73%), and 57% have secured employment to follow graduation. Five (10%) had a pending job position put on hold due to the pandemic. Conclusions Despite the impact of the COVID-19 pandemic, current accredited trainees remain well-positioned to obtain proficiency and enter the work-force