Combinatorial optimization for job sequencing with one common and multiple secondary resources by using a SAT solver augmented with a domain-specific heuristic

This paper solves job sequencing with one common and multiple secondary resources (JSOCMSR) problem by encoding it as a Boolean satisfiability (SAT) problem and applying domain-specific heuristics to improve the SAT solver’s performance. JSOCMSR problem is an NP-hard scheduling problem where each job utilizes two resources: a shared resource and...

Integration of variable selection heuristics into a MaxSAT solver for solving the multi-mode resource-constrained project scheduling problem

The multi-mode resource-constrained project scheduling problem (MRCPSP) is an extension of the resource-constrained project scheduling problem (RCPSP), which allows activities to be executed in multiple modes. The state-of-the-art solutions for solving this NP-Hard problem are dedicated algorithms and (meta-)heuristics. However, this paper...

Surgery scheduling: Dealing with overtime

Surgical scheduling is a complex task that requires consideration of various factors, including the probability of overtime. In this study, we address the research problem of surgery scheduling while accounting for the likelihood of exceeding scheduled operating room (OR) time. To tackle this problem, we employ integer linear programming (ILP)...

Heuristic Augmentation of SAT Solvers for MRCPSP

The multi-mode resource-constrained project scheduling problem (MRCPSP) is an NP-hard scheduling problem that concerns activities with several execution modes connected by precedence relations. Precedence relations define a partial ordering in which activities must be processed. The execution mode of an activity defines its processing time and...

Robustness Analysis for the Re-entrant Flow Shop Problem

Scheduling is required in almost every industry and when done well it can bring a lot of revenue. Flexibility is often forgotten when creating the initial schedules. Therefore, in case of an unexpected delay, the whole schedule has to suffer. In this paper, we consider a re-entrant flow shop with sequence-dependent setup times and relative due...

An efficient metaheuristic to solve the project portfolio selection and scheduling problem for industrial projects

Industrial companies aim for optimizing profit from delivering project outcomes. Maximizing profit relies on optimization of using resources, production capacity and available time. To reach this goal, companies are typically reliant on planning and production schedules. This problem is known as the project portfolio selection and scheduling...

Autonomous Temperature Sensor for Smart Agriculture: Wireless communication & Networking

In this thesis, the design and implementation of a wireless communication module and an accompanying network are discussed. This wireless communication module is used in a device which communicates frost temperatures measured at orchards. The goal is to gather data on how fruit frost develops on orchards, and to warn a fruit farmer if it starts...

Multi-inference on the Edge: Scheduling Networks with Limited Available Memory

The execution of multi-inference tasks on low-powered edge devices has become increasingly popular in recent years for adding value to data on-device. The focus of the optimization of such jobs has been on hardware, neural network architectures, and frameworks to reduce execution speed. However, it is yet not known how different scheduling...

Annualized hours: Comparing an exact optimization model with its approximation

In this thesis, we propose two mixed integer linear program formulations for an optimization problem that incorporates annualized hours: an exact one and an approximation. The objective of our model consists of three weighted parts: a part which minimizes the difference between working hours and contract hours for each employee per week, a part...

Scheduling an international relay-run

Roparun is a Foundation that organizes a yearly relay race from Paris, Hamburg and Almelo to Rotterdam in order to raise money for a variety of causes related to palliative care. They requested for an application that could create the start schedule of the race. In this thesis, the problem is analyzed and a greedy based solution is presented....

Using Temporal Constraint Networks for Smart Grid Scheduling

Smart Grid scheduling problems are characterized by quickly changing situations and multiple external factors that cannot be controlled. Most smart grid research applies stochastic models over the total power consumption of a household or system to find a schedule that achieves an optimization, a balancing, or constraint satisfaction. While...

Teaching Assistant Management Platform: Automating the recruitment and scheduling of teaching assistants

The majority of the courses in the Computer Science Bachelor at the Delft University of Technology use so called lab sessions to provide an opportunity for students to ask questions about course material and get feedback on their assignment. In order to optimally support the students, teaching assistants, or TAs, are appointed to assist the...

Empirical Analysis of Decremental Temporal Reasoning Algorithms

Efficient reasoning about time is crucial for robot operation, planning, and many other applications. A widespread representation used for reasoning about time is the so-called Simple Temporal Network (STN). Students at TU Delft previously developed and implemented algorithms for performing incremental reasoning over STNs. These algorithms...