Juergen Branke

University of Warwick

59Publications

16H-index

2,202Citations

Publications 59

Newest*
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Identifying efficient solutions via simulation: myopic multi-objective budget allocation for the bi-objective case*
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Estimated H-index: 16

Estimated H-index: 2

Simulation optimisation offers great opportunities in the design and optimisation of complex systems. In the presence of multiple objectives, there is usually no single solution that performs best on all objectives. Instead, there are several Pareto-optimal (efficient) solutions with different trade-offs which cannot be improved in any objective without sacrificing performance in another objective. For the case where alternatives are evaluated on multiple stochastic criteria, and the performance...

Estimated H-index: 1

Estimated H-index: 16

Estimated H-index: 8

Human resource planning in home healthcare is gaining importance day by day since companies in developed and developing countries face serious nurse and caregiver shortages. In the problem considered in this paper, the decision of patient assignment must be made immediately when the patient request arrives. Once patients have been accepted, they are serviced at the same days, times and by same nurse during their episode of care. The objective is to maximise the number of patient visits for a set...

Estimated H-index: 1

Estimated H-index: 16

Estimated H-index: 8

The importance of home healthcare is growing rapidly since populations of developed and even developing countries are getting older and the number of hospitals, retirement homes, and medical staff do not increase at the same rate. We consider the Home Healthcare Nurse Scheduling Problem where patients arrive dynamically over time and acceptance and appointment time decisions have to be made as soon as patients arrive. The objective is to maximise the average number of daily visits for a single n...

Published on Dec 11, 2018

Estimated H-index: 15

Estimated H-index: 32

This paper uses a Genetic Programming Hyper-Heuristic (GPHH) to evolve routing policies for the Uncertain Capacitated Arc Routing Problem (UCARP). Given a UCARP instance, the GPHH evolves feasible solutions in the form of decision making policies which decide the next task to serve whenever a vehicle completes its current service. Existing GPHH approaches have two drawbacks. First, they tend to generate small routes by routing through the depot and refilling prior to the vehicle being fully load...

Estimated H-index: 2

Estimated H-index: 16

Abstract This paper considers the problem of simultaneously identifying the optima for a (continuous or discrete) set of correlated tasks, where the performance of a particular input parameter on a particular task can only be estimated from (potentially noisy) samples. This has many applications, for example, identifying a stochastic algorithm’s optimal parameter settings for various tasks described by continuous feature values. We adapt the framework of Bayesian Optimisation to this problem. We...

Optimizing agents with genetic programming : an evaluation of hyper-heuristics in dynamic real-time logistics*
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Estimated H-index: 4

Estimated H-index: 16

Estimated H-index: 22

Dynamic pickup and delivery problems (PDPs) require online algorithms for managing a fleet of vehicles. Generally, vehicles can be managed either centrally or decentrally. A common way to coordinate agents decentrally is to use the contract-net protocol (CNET) that uses auctions to allocate tasks among agents. To participate in an auction, agents require a method that estimates the value of a task. Typically, this method involves an optimization algorithm, e.g. to calculate the cost to insert a ...

A Multi-objective Time-Linkage Approach for Dynamic Optimization Problems with Previous-Solution Displacement Restriction*
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Published on Apr 3, 2018

Estimated H-index: 9

Estimated H-index: 13

Estimated H-index: 1

Dynamic optimization problems (DOPs) are problems that change over time and many real-world problems are classified as DOPs. However, most of investigations in this domain are focused on tracking moving optima (TMO) without considering any other objectives which creates a gap between real-world problems and academic research in this area. One of the important optimization objectives in many real-world problems is previous-solution displacement restriction (PSDR) in which successive solutions sho...

Estimated H-index: 9

Estimated H-index: 7

Estimated H-index: 16

This paper deals with a stochastic multi-period task-resource allocation problem. A team of agents with a set of resources is to be deployed on a multi-period mission with the goal to successfully complete as many tasks as possible. The success probability of an agent assigned to a task depends on the resources available to the agent. Unsuccessful tasks can be tried again at later periods. While the problem can in principle be solved by dynamic programming, in practice this is computationally pr...

Estimated H-index: 44

Estimated H-index: 16

Estimated H-index: 8

This paper proposes a simulated annealing variant for optimization problems in which the solution quality can only be estimated by sampling from a random distribution. The aim is to find the solution with the best expected performance, as, e.g., is typical for problems where solutions are evaluated using a stochastic simulation. Assuming Gaussian noise with known standard deviation, we derive a fully sequential sampling procedure and decision rule. The procedure starts with a single sample of th...

Published on Dec 3, 2017

Estimated H-index: 2

Estimated H-index: 16

This paper considers the problem of identifying the best of a discrete set of alternatives for each of a set of correlated problem instances. We assume that the instances can be described by a set of continuous features and the performance of a particular alternative on a particular problem instance can only be estimated from noisy samples. A possible application is in manufacturing, where we would like to identify the best dispatching rule to be used depending on shop floor conditions, and perf...

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Co-Authors

Sanaz Mostaghim

H-index : 21

Tim Blackwell

H-index : 20

Hartmut Schmeck

H-index : 27

Trung Thanh Nguyen

H-index : 13

Christian Schmidt

H-index : 9