Dissertation Project
Design and Control of Stochastic Manufacturing Systems
Date of Defense
15 July 2022
Research Interest
My research focuses on the design and control of stochastic manufacturing systems. Problems include the optimal design of an assembly line with generally distributed task times or the start of production decision in the ramp-up of semiconductor manufacturing.
Our research focuses on the design and control of stochastic manufacturing systems. Flow lines are common in many industries producing in large quantities. We analyze the assembly line balancing problem with stochastic task times. We consider the optimization problem of minimizing the number of stations with a constraint on the probability of finishing a work piece within the given cycle time. Technical precedence relations have to be fulfilled and each task has to be assigned to exactly one station.
In addition to this design problem, we analyze the optimal start of production in a ramp-up process which faces stochastic yield. Yield problems occur when some of the produced products do not meet the specifications and can therefore not be used to fulfill demand. The yield distribution of a production process could change over time, depending on the past production volume.
Diefenbach, J, Stolletz, R (2022): Stochastic Assembly Line Balancing: General Bounds and Reliability-based Branch-and-Bound Algorithm. European Journal of Operational Research. DOI: 0.1016/j.ejor.2022.01.015
Diefenbach, J. M., Schwarz, J. A., and R. Stolletz (2019): Second thoughts on not so random sampling. 8th Workshop on Queueing Theory, Obergurgl, Austria, December 2019.
Diefenbach, J. M. and R. Stolletz (2019): Data-driven line balancing: bounds and optimization. Young European Queueing Theorists, Eindhoven, Netherlands, October 2019
Schnitzler, J. M., Schwarz, J. A., and R. Stolletz (2019): Impact of stochastic yield with learning on start of production. SMMSO 2019, Goslar, Germany, June 2019.
Schnitzler, J. M., Schwarz, J. A., and R. Stolletz (2019): Impact of stochastic yield with learning on start of production. Productive4.0 Research Workshop, Istanbul, Turkey, January 2019.
Schnitzler, J. M., Schwarz, J. A., and R. Stolletz (2018): First “random thoughts” on not so random sampling. 7th Workshop on Queueing Theory, Obergurgl, Austria, December 2018.
Schnitzler, J. M. and R. Stolletz (2018): A branch and bound procedure for the chance-constrained stochastic assembly line balancing problem. Automotive Workshop, Frankfurt (Oder), November 2018
Schnitzler, J. M. and R. Stolletz (2018): A branch and bound procedure for the stochastic assembly line balancing problem. EURO 2018, Valencia, Spain, July 2018.
Schnitzler, J. M. and R. Stolletz (2018): A branch and bound procedure for the stochastic assembly line balancing problem. 28. Workshop der Quantitativen Betriebswirtschaftslehre, Hoechst, Germany, March 2018.
Schnitzler, J. M. and R. Stolletz (2017): A branch and bound procedure for the stochastic assembly line balancing problem. 6th Workshop on Queueing Theory, Obergurgl, Austria, December 2017.
Schnitzler, J. M. and R. Stolletz (2017): A sampling approach for line balancing with stochastic task completion times. 27. Workshop der Quantitativen Betriebswirtschaftslehre, Klappholttal (Sylt), March 2017.
Schnitzler, J. M. and R. Stolletz (2016): A sampling approach for line balancing with stochastic task completion times. 5th Workshop on Queueing Theory, Obergurgl, Austria, December 2016.
Schnitzler, J. M. and R. Stolletz (2016): Line balancing with stochastic task completion times – numerical investigation of a sampling approach. Automotive Workshop, Hagen, September 2016.
Scholarship of the Graduate School of Economic & Social Sciences (GESS), University of Mannheim (funded by the German Research Foundation (DFG) as part of the 'Excellence Initiative'), September 2016 – October 2017.
Education
09/
2016 – 07/ 2022
Doctoral Studies in Business Administration, Chair of Production Management (Prof. Stolletz), University of Mannheim
09/2016 – present
Doctoral Studies in Operations (Ph.D. Program), Center for Doctoral Studies in Business (CDSB), University of Mannheim09/
2014 – 08/ 2016
Mannheim Master Management (M. Sc.), University of Mannheim09/
2011 – 08/ 2014
Studies in Business Administration (B. Sc.), University of Mannheim08/
2013 – 12/ 2013
Studies in Business Administration (semester abroad), Montana State Univeristy09/
2001 – 06/ 2010
Abitur, Carl-Benz Gymnasium, LadenburgProfessional experience
09/
2016 – 12/ 2020
Research Assistant, Chair of Production Management (Prof. Stolletz), University of Mannheim03/
2015 – 07/ 2016
Working Student, Daimler AG, Mannheim – Production Scheduling07/
2014 – 12/ 2014
Intern, Daimler AG, Mannheim – Production Scheduling01/
2013 – 2/ 2013
Intern, PERI GmbH, Weißenhorn – Corporate Development06/
2012 – 05/ 2012
President of the Chapter Mannheim of MTP e.V.