- Scheduling seminar - list.iid.ciirc.cvut.cz

Pascal Van Hentenryck (Georgia Tech) | April 13 | Constraint Programming for Scheduling
by Zdeněk Hanzálek 11 Apr '22

11 Apr '22

Dear scheduling researcher, We are delighted to announce the talk given by Pascal Van Hentenryck (Georgia Tech). The title is "Constraint Programming for Scheduling". The seminar will take place on Zoom on Wednesday, April 13 at 13:00 UTC. Join Zoom Meeting https://cesnet.zoom.us/j/94015623000?pwd=eThCQmZwZjJpdExEK2g0TWUvLzZuZz09 Meeting ID: 940 1562 3000 Passcode: 808863 You can follow the seminar online or offline on our Youtube channel as well: https://www.youtube.com/channel/UCUoCNnaAfw5NAntItILFn4A The abstract follows. This talk reviews the start of the art in solving scheduling problems with constraint programming, and examines novel research directions, with a focus on the integration of constraint programming and mathematical programming, and the use of machine learning. It reviews applications where constraint programming provides an integrated approach to complex problems, the hybridization of constraint programming and mathematical programming, learning-based constraint programming, and optimization proxies. The next talk in our series will be given by: Iiro Harjunkoski (Hitachi Energy) | April 27 | Scheduling and Energy – Industrial Challenges and Opportunities For more details, please visit https://schedulingseminar.com/ With kind regards Zdenek, Mike and Guohua -- Zdenek Hanzalek Industrial Informatics Department, Czech Institute of Informatics, Robotics and Cybernetics, Czech Technical University in Prague, Jugoslavskych partyzanu 1580/3, 160 00 Prague 6, Czech Republic https://rtime.ciirc.cvut.cz/~hanzalek/

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Christian Artigues (LAAS - CNRS) | March 30 | Mixed integer linear programming for resource-constrained scheduling
by Zdeněk Hanzálek 28 Mar '22

28 Mar '22

Dear scheduling researcher, We are delighted to announce the talk given by Christian Artigues (LAAS - CNRS). The title is "Mixed integer linear programming for resource-constrained scheduling". The seminar will take place on Zoom on Wednesday, March 30 at 13:00 UTC. Join Zoom Meeting https://cesnet.zoom.us/j/91490324777?pwd=dFV0UjRlL2UyZUg1ZC9ZdGtJb2FqUT09 Meeting ID: 914 9032 4777 Passcode: 848529 You can follow the seminar online or offline on our Youtube channel as well: https://www.youtube.com/channel/UCUoCNnaAfw5NAntItILFn4A The abstract follows. Mixed-Integer linear programming (MILP) is one of the generic modeling and algorithmic solution framework for NP-hard scheduling problems, along with Constraint Programming (CP) and SAT solvers. However, the literature often reports poor results of MILP solvers for resource-constrained scheduling problems compared to CP or SAT-based approaches such as Lazy Clause Generation. However, even if this is partly true because of the powerful dedicated scheduling algorithms embedded in constraint propagators, MILP approaches can reach very good results in terms of primal and dual bounds if the right formulation and specialized MILP components such as valid inequalities and column generation are chosen for the problem at hand. This talk first reviews the standard MILP formulations for resource-constrained scheduling problems and a few recent advances in the field. In particular, we focus on basic polyhedral results, on the relative relaxation strength of compact and extended formulations augmented with valid inequalities. Finally, we provide examples, including industrial ones where MILP, possibly integrated in hybrid CP/SAT/MILP methods, appears as a technique of choice. The next talk in our series will be given by: Pascal Van Hentenryck (Georgia Tech) | April 13 | Constraint Programming for Scheduling For more details, please visit https://schedulingseminar.com/ With kind regards Zdenek, Mike and Guohua -- Zdenek Hanzalek Industrial Informatics Department, Czech Institute of Informatics, Robotics and Cybernetics, Czech Technical University in Prague, Jugoslavskych partyzanu 1580/3, 160 00 Prague 6, Czech Republic https://rtime.ciirc.cvut.cz/~hanzalek/

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Lars Mönch (Uni of Hagen) | March 16 | Scheduling Problems in Semiconductor Wafer Fabrication Facilities: Part 2
by Zdeněk Hanzálek 14 Mar '22

14 Mar '22

Dear scheduling researcher, We are delighted to announce the talk given by Lars Mönch (Uni of Hagen). The title is "Scheduling Problems in Semiconductor Wafer Fabrication Facilities: Part 2". The seminar will take place on Zoom on Wednesday, March 16 at 14:00 UTC. Join Zoom Meeting https://cesnet.zoom.us/j/94701637415?pwd=TWI4ZDVINUNRd3pjWktQNjFDRXJJZz09 Meeting ID: 947 0163 7415 Passcode: 919535 You can follow the seminar online or offline on our Youtube channel as well: https://www.youtube.com/channel/UCUoCNnaAfw5NAntItILFn4A The abstract follows. Semiconductors enable the systems and products that we use to work, communicate, travel, entertain, harness the energy, treat illness, make new scientific discoveries, and more. Semiconductor manufacturing is among the most complex manufacturing systems in existence today. This complexity makes scheduling semiconductor manufacturing systems extremely difficult. In this two-part seminar, we discuss scheduling problems in this challenging domain. In the second part, we discuss batch scheduling problems, multiple orders per job scheduling problems, and scheduling problems that include time lags for the jobs. Moreover, scheduling problems related to cluster tools will be also briefly considered. Solution techniques, mainly based on problem decomposition and metaheuristics, will be also discussed. Finally, future research direction for scheduling semiconductor wafer fabrication facilities will be identified. The next talk in our series will be given by: Christian Artigues (LAAS - CNRS) | March 30 | Mixed integer linear programming for resource-constrained scheduling For more details, please visit https://schedulingseminar.com/ With kind regards Zdenek, Mike and Guohua -- Zdenek Hanzalek Industrial Informatics Department, Czech Institute of Informatics, Robotics and Cybernetics, Czech Technical University in Prague, Jugoslavskych partyzanu 1580/3, 160 00 Prague 6, Czech Republic https://rtime.ciirc.cvut.cz/~hanzalek/

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[Scheduling seminar] John W. Fowler (Arizona State Univ.) | March 2 | Scheduling Problems in Semiconductor Wafer Fabrication Facilities: Part 1
by Zdeněk Hanzálek 28 Feb '22

28 Feb '22

Dear scheduling researcher, We are delighted to announce the talk given by John W. Fowler (Arizona State Univ.). The title is " Scheduling Problems in Semiconductor Wafer Fabrication Facilities: Part 1". The seminar will take place on Zoom on Wednesday, March 2 at 14:00 UTC. Join Zoom Meeting https://cesnet.zoom.us/j/96133782270?pwd=VVFGRGJoSS9IZ1d5NkRyamFiZUh5QT09 Meeting ID: 961 3378 2270 Passcode: 292650 You can follow the seminar online or offline on our Youtube channel as well: https://www.youtube.com/channel/UCUoCNnaAfw5NAntItILFn4A The abstract follows. Semiconductors enable the systems and products that we use to work, communicate, travel, entertain, harness energy, treat illness, make new scientific discoveries, and more. Semiconductor manufacturing is among the most complex manufacturing systems in existence today. This complexity makes scheduling semiconductor manufacturing systems extremely difficult. In this two-part seminar, we discuss scheduling problems in this challenging domain. In the first part, we describe the manufacturing process and identify typical scheduling problems found in semiconductor manufacturing systems at the workstation, work area, factory, and supply chain levels. We also discuss approaches for scheduling problems with secondary resources and for factory level scheduling. The next talk in our series will be given by: Lars Mönch (Uni of Hagen) | March 16 | Scheduling Problems in Semiconductor Wafer Fabrication Facilities: Part 2 For more details, please visit https://schedulingseminar.com/ With kind regards Zdenek, Mike and Guohua -- Zdenek Hanzalek Industrial Informatics Department, Czech Institute of Informatics, Robotics and Cybernetics, Czech Technical University in Prague, Jugoslavskych partyzanu 1580/3, 160 00 Prague 6, Czech Republic https://rtime.ciirc.cvut.cz/~hanzalek/

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Kangbok Lee (POSTECH) | February 16 | Scheduling Heuristics for Steelmaking Continuous Casting Processes
by Zdeněk Hanzálek 14 Feb '22

14 Feb '22

Dear scheduling researcher, We are delighted to announce the talk given by Kangbok Lee (POSTECH, Korea). The title is "Scheduling Heuristics for Steelmaking Continuous Casting Processes". The seminar will take place on Zoom on Wednesday, February 16 at 14:00 UTC. Join Zoom Meeting https://cesnet.zoom.us/j/91094063787?pwd=d01UbWRPOHJQUy93dnBhWU5QclRLQT09 Meeting ID: 910 9406 3787 Passcode: 284143 You can follow the seminar online or offline on our Youtube channel as well: https://www.youtube.com/channel/UCUoCNnaAfw5NAntItILFn4A The abstract follows. Steelmaking-Continuous Casting (SCC) is a bottleneck in the steel production process and its scheduling has become more challenging over time. In this paper, we provide an extensive literature review that highlights challenges in the SCC scheduling and compares existing solution methods. From the literature review, we collect the essential features of an SCC process, such as unrelated parallel machine environments, stage skipping, and maximum waiting time limits in between successive stages. We consider an SCC scheduling problem with as objective the minimisation of the weighted sum of cast break penalties, total waiting time, total earliness, and total tardiness. We formulate the problem as a mixed-integer linear programming model and develop an iterated greedy matheuristic that solves its subproblems to find a near-optimal solution. Through numerical experiments, we show that our algorithm outperforms two types of genetic algorithms when applied to test instances. The next talk in our series will be given by: John W. Fowler (Arizona State Univ.) | March 2 | Scheduling Problems in Semiconductor Wafer Fabrication Facilities: Part 1 For more details, please visit https://schedulingseminar.com/ With kind regards Zdenek, Mike and Guohua -- Zdenek Hanzalek Industrial Informatics Department, Czech Institute of Informatics, Robotics and Cybernetics, Czech Technical University in Prague, Jugoslavskych partyzanu 1580/3, 160 00 Prague 6, Czech Republic https://rtime.ciirc.cvut.cz/~hanzalek/

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Yindong Shen (AIA Huazhong Uni) | February 2| Public transit planning and scheduling based on AVL data in China
by Zdeněk Hanzálek 31 Jan '22

31 Jan '22

Dear scheduling researcher, We are delighted to announce the talk given by Yindong Shen (AIA Huazhong Uni). The title is "Public transit planning and scheduling based on AVL data in China". The seminar will take place on Zoom on Wednesday, February 2 at 14:00 UTC. Join Zoom Meeting https://cesnet.zoom.us/j/93999293735?pwd=S0R4Z0xPckVjdjd6ejRBbjVyZlZ6dz09 Meeting ID: 939 9929 3735 Passcode: 992845 You can follow the seminar online or offline on our Youtube channel as well: https://www.youtube.com/channel/UCUoCNnaAfw5NAntItILFn4A The abstract follows. The public transit operations planning process commonly includes the following activities: network route design, service planning (frequency setting and timetabling) and scheduling (vehicle scheduling, crew scheduling and rostering). However, network route design is generally the only one widely recognized, whilst service planning and scheduling are often ignored in China. This leads to the lack of elaborate timetables and schedules, hence, transit operation is often in disorder with high operating costs. To raise the service level and the utilization of resources, an applied study for three cities in China has been conducted, focusing on the enhancement of the recognition and execution of public transit planning and scheduling. A comprehensive framework of public transit planning is first proposed, which is composed of three traditional Chinese items (i.e. network route design, land use for depots, and deployment of vehicles) and the following newly added items: intelligent public transit system (iPTS) planning, service planning, and scheduling. This is pioneering work in China, during which an iPTS plan is conceived and a new vehicle scheduling approach based on AVL data is developed. Experiments during actual projects show that vehicle schedules with high on-time probability and low cost were compiled, while the essential input parameters such as headways and trip times were set automatically. It is anticipated that the research fruits and practical experiences obtained would be of great benefit in improving service and management levels and resource use in public transport in China and some other developing countries. The next talk in our series will be given by: Kangbok Lee (POSTECH)| February 16| Scheduling Heuristics for Steelmaking Continuous Casting Processes For more details, please visit https://schedulingseminar.com/ With kind regards Zdenek, Mike and Guohua -- Zdenek Hanzalek Industrial Informatics Department, Czech Institute of Informatics, Robotics and Cybernetics, Czech Technical University in Prague, Jugoslavskych partyzanu 1580/3, 160 00 Prague 6, Czech Republic https://rtime.ciirc.cvut.cz/~hanzalek/

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Dvir Shabtay (Ben-Gurion Uni)| January 19| On the Parameterized Complexity of Machine Scheduling Problems
by Zdeněk Hanzálek 17 Jan '22

17 Jan '22

Dear scheduling researcher, We are delighted to announce the talk given by Dvir Shabtay (Ben-Gurion Uni). The title is "On the Parameterized Complexity of Machine Scheduling Problems". The seminar will take place on Zoom on Wednesday, January 19 at 14:00 UTC. Join Zoom Meeting https://cesnet.zoom.us/j/94434108596?pwd=UTFuT2V3VjRiT3dwTENwRStZSkxPdz09 <https://cesnet.zoom.us/j/94434108596?pwd=UTFuT2V3VjRiT3dwTENwRStZSkxPdz09> Meeting ID: 944 3410 8596 Passcode: 384746 You can follow the seminar online or offline on our Youtube channel as well: https://www.youtube.com/channel/UCUoCNnaAfw5NAntItILFn4A The abstract follows. The main goal of parameterized complexity is to try to design algorithms that are capable of solving (in reasonable time) hard problems in cases where some predefined problem parameters are of limited size. This theory was developed in the early 90s, contributing to many new techniques in the area of algorithmic design ever since. In this talk we survey the main aspects of parametrized complexity, and highlight its applicability to the area of scheduling. We also discuss some challenges and open problems for future research. The next talk in our series will be given by Yindong Shen (AIA Huazhong Uni) | February 2, 2022| Public transit planning and scheduling based on AVL data in China For more details, please visit https://schedulingseminar.com/ With kind regards Zdenek, Mike and Guohua -- Zdenek Hanzalek Industrial Informatics Department, Czech Institute of Informatics, Robotics and Cybernetics, Czech Technical University in Prague, Jugoslavskych partyzanu 1580/3, 160 00 Prague 6, Czech Republic https://rtime.ciirc.cvut.cz/~hanzalek/

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Rubén Ruiz (UP de València)| December 22| State-of-the-art flowshop scheduling heuristics: Dos and Don'ts
by Zdeněk Hanzálek 20 Dec '21

20 Dec '21

Dear scheduling researcher, We are delighted to announce the talk given by Rubén Ruiz (UP de València). The title is "State-of-the-art flowshop scheduling heuristics: Dos and Don'ts". The seminar will take place on Zoom on Wednesday, December 22 at 14:00 UTC. Join Zoom Meeting https://cesnet.zoom.us/j/91381308994?pwd=bFgzTFR1ZzlNNHpybTc5YTlTTHRxQT09 Meeting ID: 913 8130 8994 Passcode: 212305 You can follow the seminar online or offline on our Youtube channel as well: https://www.youtube.com/channel/UCUoCNnaAfw5NAntItILFn4A The abstract follows. Many scheduling problems are simply too hard to be solved exactly, especially for instances of medium or large size or when realistic constraints are present. As a result, the literature on heuristics and metaheuristics for scheduling is extensive. More often than not, metaheuristics are capable of generating solutions close to optimality or to tight lower bounds for instances of realistic size in a matter of minutes. Metaheuristics have been refined over the years and there are literally hundreds of papers published every year with applications to most domains in many different journals. Most regrettably, some of these methods are complex in the sense that they have many parameters that affect performance and hence need careful calibration. Furthermore, many times published results are hard to reproduce due to specific speed-ups being used or complicated software constructs. These complex methods are difficult to transfer to industries in the case of scheduling problems. Another important concern is the recently recognized “tsunami” of novel metaheuristics that mimic the most bizarre natural or human processes, as for example intelligent water drops, harmony search, firefly algorithms and the like. See K. Sörensen “Metaheuristics—The Metaphor exposed” (2015), ITOR 22(1):3-18. In this presentation, we briefly review different flowshop problems and variants. From the basic flowshop problem with makespan minimization to other objectives like flowtime minimization, flowshops with sequence-dependent setup times, no-idle flowshops, all the way up to complex hybrid flexible flowline problems. We will show how simple Iterated Greedy (IG) algorithms often outperform much more complex approaches. IG methods are inherently simple with very few parameters. They are easy to code and results are easy to reproduce. We will show that for all tested problems so far they show state-of-the-art performance despite their simplicity. As a result, we will defend the choice of simpler, yet good performing approaches over complicated metaphor-based algorithms. The next talk in our series will be given by Christian Artigues (LAAS-CNRS Toulouse)| December 22| For more details, please visit https://schedulingseminar.com/ With kind regards Zdenek, Mike and Guohua -- Zdenek Hanzalek Industrial Informatics Department, Czech Institute of Informatics, Robotics and Cybernetics, Czech Technical University in Prague, Jugoslavskych partyzanu 1580/3, 160 00 Prague 6, Czech Republic https://rtime.ciirc.cvut.cz/~hanzalek/

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Christoph Dürr (Sorbonne Uni)| December 8 | Three models for scheduling under explorable uncertainty
by Zdeněk Hanzálek 06 Dec '21

06 Dec '21

Dear scheduling researcher, We are delighted to announce the talk given by Christoph Dürr <http://www.lip6.fr/Christoph.Durr> (Sorbonne Uni). The title is "Three models for scheduling under explorable uncertainty". The seminar will take place on Zoom on Wednesday, December 8 at 14:00 UTC. Join Zoom Meeting https://cesnet.zoom.us/j/94434410356?pwd=SWlmUElObjhtQWZCcm9PZGw5TTVnZz09 <https://cesnet.zoom.us/j/94434410356?pwd=SWlmUElObjhtQWZCcm9PZGw5TTVnZz09> Meeting ID: 944 3441 0356 Passcode: 040955 You can follow the seminar online or offline on our Youtube channel as well: https://www.youtube.com/channel/UCUoCNnaAfw5NAntItILFn4A The abstract follows. We consider a single machine scheduling problem, where every job has a processing time and a priority weight and the objective is to minimize the total weighted sum of completion times. The novelty is that the job characteristics are initially given in an imprecise manner to the algorithm. Tests can be performed for chosen jobs to learn their precise values, allowing for a better ordering of the jobs in the schedule. These tests however take some time, delaying the subsequent schedule. The algorithm needs to produce a schedule consisting of executions of all jobs and tests of some jobs. We will present three different models that have been studied in this context, as well as the results obtained for each of them. The talk covers papers authored by Levi, Magnanti and Shaposhnik, by C.D., Thomas Erlebach, Nicole Megow, Julie Meißner, and by Fanny Dufossé, C.D., Noël Nadal, Denis Trystram and Óscar C. Vásquez. The next talk in our series will be given by Rubén Ruiz (UP de València)| December 22| State-of-the-art flowshop scheduling heuristics: Dos and Don'ts For more details, please visit https://schedulingseminar.com/ With kind regards Zdenek, Mike and Guohua -- Zdenek Hanzalek Industrial Informatics Department, Czech Institute of Informatics, Robotics and Cybernetics, Czech Technical University in Prague, Jugoslavskych partyzanu 1580/3, 160 00 Prague 6, Czech Republic https://rtime.ciirc.cvut.cz/~hanzalek/

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Michel Gendreau (Polytech Montréal) | November 24 | Tabu search for the time-dependent vehicle routing problem with time windows on a road network
by Zdeněk Hanzálek 22 Nov '21

22 Nov '21

Dear scheduling researcher, We are delighted to announce the talk given by Michel Gendreau (Polytech Montréal). The title is "Tabu search for the time-dependent vehicle routing problem with time windows on a road network". The seminar will take place on Zoom on Wednesday, November 24 at 14:00 UTC. Join Zoom Meeting https://cesnet.zoom.us/j/94687225692?pwd=SWVESXR6djcvWkpxeUc3a0xiLzVNQT09 Meeting ID: 946 8722 5692 Passcode: 557044 You can follow the seminar online or offline on our Youtube channel as well: https://www.youtube.com/channel/UCUoCNnaAfw5NAntItILFn4A The abstract follows. Travel times inside cities often vary quite a lot during a day and significantly impact the duration of delivery routes. Some authors have proposed time-dependent (TD) variants of several vehicle routing problems (VRPs), including the VRP with time windows (VRPTW). In most papers, time-dependency is defined on customer-based graphs. Thus, a major impact of travel time variations is missed: in an urban environment, not only do travel times change, but also the paths used to travel from one customer to another. To address this issue, we work directly with the road network and consider travel time (or travel speed) variations on each road segment. We present a solution approach, based on tabu search, for a TDVRPTW in which travel speeds are associated with segments in the road network. Computational results on instances with up to 200 nodes and 580 arcs are reported and assessed. (Joint work with Maha Gmira, Andrea Lodi, and Jean-Yves Potvin). The next talk in our series will be given by Christoph Dürr (Sorbonne Uni)| December 8 | Three models for scheduling under explorable uncertainty For more details, please visit https://schedulingseminar.com/ With kind regards Zdenek, Mike and Guohua -- Zdenek Hanzalek Industrial Informatics Department, Czech Institute of Informatics, Robotics and Cybernetics, Czech Technical University in Prague, Jugoslavskych partyzanu 1580/3, 160 00 Prague 6, Czech Republic https://rtime.ciirc.cvut.cz/~hanzalek/

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