Academic articles

Forest Equipment Planning–From Spreadsheet to Simple Dynamic Model


Forest equipment planning and availability depend on forest management and harvesting regimes in addition to the market demand. This project aims to support the equipment planning process by estimating the future need of forest equipment with different forest management options. The number of required machinery depends on how much feedstock is available. It also depends on how much biomass was processed by previous machines in the system. The number of products that the machine in question has to process varies based on the supply chain structure.

Production Planning: Simulation Based Predictive Analytics Solution and Evalutation of Forecast Error Measures


Production planning is usually performed based on customer orders or demand forecasts. The demand forecasts in production systems can either be generated by manufacturing companies themselves, i.e. forecast prediction or they can be provided by customers. For both alternatives, forecast prediction, as well as the customer-provided forecasts, the quality of those forecasts is critical for success. In this paper, predictive analytics simulation modeling is used to generate forecast data that mimic different forecast behaviors.

Transportation Optimization Model of an Ambulance System in India


According to a World Health Organization (WHO) report in 2018, 1.35 million people die each year due to road accidents globally. In a country like India, it is becoming increasingly difficult to provide post-accident services on time with an increase in congestion. In this paper, the researchers propose a system which decreases the post-accident response time of Emergency Medical Services (EMS) in India by adding another layer of the patient transport vehicle. Based on a transportation system analysis, the paper discusses a new algorithm and a system design with a transportation optimization simulation model.

Airport Passenger Shopping Modeling and Simulation: Targeting Distance Impacts


The ever-increasing importance of airport retail has encouraged both industry and academics to look into ways to increase airport retail revenue. Despite the growing interest in this topic, there is a lack of passenger shopping behavioral model. This paper aims to fill this gap and enhance our understanding of how the location of the shop affects passenger decision. This paper first investigates the possible passenger shopping behavioral model through an exploratory Eye-tracking exercise. Data was collected to calibrate and validate the behavioral model through the use of an Agent-Based Simulation Model.

STTAR: a Simheuristics-enabled Scheme for Multi-stakeholder Coordination of Aircraft Turnaround Operations


Aircraft ground handling involves all services to an aircraft (e.g. passenger boarding/disembarking, re-fuelling, deicing) between its arrival and immediately following departure. The aircraft, parked at its stand, witnesses a number of service providers move around it to perform their duties. Inter-dependencies among service providers abound, and knock-on effects at disrupted times are rife. Coordination from the side of the airport operator is difficult.

The research team proposes a tactical robust scheme by which ground handlers and the airport operator cooperate, although indirectly, in the development of plans for the next day that are less likely to be impacted by at least the more frequent operational disruptions. The scheme is based on a simheuristic approach which integrates ad-hoc heuristics with a hybrid simulation model (agent-based/discrete-event).

Open Pit Optimization for Short-term Forecasting Using Mining Simulator


Simulation modelling has long been used as a decision support tool in the mining industry. This is typically done to address issues on the strategic time horizon, with a heavy focus on experimentation and sensitivity analysis. These issues include mining equipment selection, pit optimization, design and operation of the mine-plant interface, testing the robustness of a mine plan and blending.

Mining simulators can be used to forecast production in the short term to test the quality of truck dispatch decisions (allocation of trucks to loaders) and evaluate the value of alternate scheduling rules. It can also be used to produce a forecast of the likelihood of achieving a shift target and allow operators to test what-if options to reduce the risk of production loss or reduce costs by putting excess equipment on standby. Being able to make these decisions with confidence helps to drive improvements in operations efficiency.

Strategic Supply Chain Design for an Austrian Winter Road Service Provider


Snowplow operations are critical for public safety and economic success in countries where difficult driving conditions occur in winter. Specifically, the salt supply ensuring good driving conditions is a crucial factor. In this paper, the strategic supply chain design of a winter service provider in Austria is investigated. Two research directions on the influence of bigger and fewer salt silos per depot and the logistic costs for a unique summer salt purchasing strategy are addressed applying two independent solution approaches. On the same data basis, a simulation model is developed and a mixed integer linear problem is applied to answer the respective research questions.

How Order Placement Influences Resource Allocation and Order Processing Times Inside a Multi-user Warehouse


This paper focuses on the influence of different order placement behavior of users on the allocation of common resources inside a multi-user warehouse. Furthermore, the interdependencies between one user’s resource usage on other users’ order processing time is investigated. For this objective, an agent-based simulation model has been developed, depicting a rectangular warehouse with two users and one order picker. Results show that different order placement behavior and resource usage of one user have a strong influence on order processing times of other users. Furthermore, by simulating uneven order placement by one user, it can be shown that peaks in order demand influence other user’s order processing times with a delay of up to two hours after the peak occurred. Thus, the results highlight the need for coordinated order placement of partners inside a multi-user warehouse.

Rail Fleet Maintenance Optimization at the UK Rail Network


This paper presents a joint simulation project in the area of railway fleet maintenance optimization. A simulation model was developed to understand and visualize the complex interaction in a railway system comprising rolling stock, depots, and maintenance guidelines. In many cases, requirements on such a system come from different sides, such as fleet operation (timetables and availability), maintenance engineering (maintenance regime), and depot management (depot restrictions). The paper describes the domain-specific challenge, the model for planned maintenance optimization, the implemented scheduling algorithm, and resulting insights. It, furthermore, describes how the model can be used for a variety of different use cases all along a railway project: from sizing to forecast and performance analysis and from initial tender theory check to operational risk analysis and preventive maintenance optimization. Two real-world use cases are presented: West Coast Main Line and TransPennine Express, both in the United Kingdom.