A column generation-based heuristic for rostering with work patterns

Lusby, Richard Martin; Dohn, Anders Høeg; Range, Troels Martin; Larsen, Jesper

doi:10.1057/jors.2011.27

Cited by 20 publications

(29 citation statements)

References 30 publications

(31 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Contributions to tour scheduling for ground handlers and other airport personnel have been made by Dowling et al (1997), Chu (2007), Ásgeirsson (2012), and Lusby et al (2011). In contrast to their work and other tour scheduling research found in the literature (e.g., see Van den Bergh et al 2013), our framework considers the most flexible break regulations and contains over-and undertime constraints for individual workers with hierarchical skill levels.…”

Section: Literature Reviewmentioning

confidence: 99%

See 1 more Smart Citation

The flexible break assignment problem for large tour scheduling problems with an application to airport ground handlers

Kiermaier

Frey

Bard

2020

J Sched

View full text Add to dashboard Cite

The paper examines the complexity of assigning multiple breaks to shifts in the context of large-scale tour scheduling. A mixed-integer programming (MIP) model is presented that includes shift and days-off scheduling along with break assignments for a multi-skilled workforce. To achieve tractability, a two-stage decomposition procedure is proposed that separates the tour scheduling problem (TShP) from the break assignment problem (BAP). The former MIP is first solved to determine the shifts and days off for the workforce that minimize labor and shortages costs over the planning horizon. The results are used as input to a second MIP that optimally places the breaks to minimize the costs of working hours and uncovered periods. Three implicit BAP formulations are investigated. To better understand the literature and the models previously developed, a 3-field break classification scheme is introduced. The first field characterizes the number of breaks permitted per shift, the second specifies whether the length of the breaks is fixed or variable, and the third limits their position in a shift. A complexity analysis of the resulting 12 BAPs along with a few special cases is also included. Most problems are shown to be strongly NP-hard. Computations are presented for a wide variety of scenarios for both the TShP and the BAP using data provided by a European airport ground handler company. In all, over 500 instances were investigated using high and low demand fluctuation curves and the various break and shift flexibility options. The results indicate that increasing flexibility in break regulations can make a significant difference in coverage, but the degree depends on the underlying structure of the demand curve as well as on the types of shifts permitted. Formulations with the most flexible shift and break regulations reduced undercoverage by up to 16.68% compared to the most common scenarios in which shifts are limited to a single lunch break.

show abstract

Section: Literature Reviewmentioning

confidence: 99%

“…Solution quality was judged by how closely the days-on and days-off assignments matched employee requests. Finally, Lusby et al (2011) tackled a ground crew rostering problem for a European airline using a column generation-based heuristic. Their goal was to create longterm rosters based on 6 days-on, 3 days-off work patterns.…”

Section: Literature Reviewmentioning

confidence: 99%

The flexible break assignment problem for large tour scheduling problems with an application to airport ground handlers

Kiermaier

Frey

Bard

2020

J Sched

View full text Add to dashboard Cite

show abstract

“…Solving the LP relaxation of (9)-(20) does not necessarily lead to an integer solution. In order to make the solution integral we apply the technique of aggressive variable fixing (see, e.g., Lusby et al (2012) or Range et al (2014). Accordingly, the integer variables are successively fixed at their upper bounds, and the column generation for (9)-(20) is run again until a new LP relaxation bound (with respect to the fixed variables) is obtained.…”

Section: Implementational Issuesmentioning

confidence: 99%

Dynamic job assignment: A column generation approach with an application to surgery allocation

Range

Kozlowski

Petersen

2019

European Journal of Operational Research

View full text Add to dashboard Cite

We consider the assignment of jobs to agents in a stochastic and dynamic setting. Focus is on a dynamic scenario with due dates and service levels reflecting the completion of jobs within certain deadlines. Due dates and other relevant characteristics for currently uncompleted jobs generated in the past are known, but the consumption of resources needed for their completion is stochastic. Distributions for the generation of future jobs as well as their characteristics are known. Capacity is limited, and an arriving job that cannot be assigned to an agent within its due date must be outsourced. Outsourcing is accompanied by a cost. We develop an optimization model based on column generation for the assignment of known and future jobs to agents such that the expected cost of outsourcing is minimum. The model is an extension of a generalized assignment problem and provides an allocation of known as well as tentative future jobs to agents. The model is embedded in a rolling horizon framework and subjected to a series of computational tests. The results indicate that taking stochastic information about future job arrivals into account in the assignment of jobs to agents implies an improved performance. The model is highly relevant in the context of patient scheduling in an operating theater. For this reason patient scheduling constitutes the storyline in the development of the model. 1 For this reason, a rescheduling is required on a regular basis.1. An explicit modeling of stochastic arrival processes and service times, where the stochastic future arrivals are incorporated into the planning problem.2. The application of a strictly convex cost function for expected overtime.3. The extension and embedding of a static one-period stochastic scheduling model into a dynamic setting.

show abstract

“…In manpower planning, robust optimization has traditionally been applied to staffing and scheduling problems (for example, Burke et al 2004, Lusby et al 2012. However, to the best of our knowledge, we haven't seen any literature on its application to longer term manpower planning.…”

Section: One Of the Earliest Attempts Was Bymentioning

confidence: 99%