Towards unmanned cargo ships: A task based design process to identify economically viable low and unmanned ship concepts

Unmanned and low-manned transport has increasingly been studied this past decade. While there have been successful trials for autonomous navigation, unmanned cargo ships are not commercially available yet. First, this dissertation investigates how changes to a ship’s systems and organizational structure can affect the crew’s size and composition...

Maximum Coverage Problems: Theory and Application in Optimal Sensor Selection

In this thesis we analyse the class of <i>maximum coverage</i> problems. For all discussed problems, linear programs are formulated. Using the notion of <i>submodularity</i>, we prove that for the weighted version of the basic <i>Maximum Coverage</i> problem, where the weights differ per set, a polynomial-time greedy algorithm guarantees a (1 -...

Integrative approach for transducer positioning optimization for ultrasonic structural health monitoring for the detection of deterministic and probabilistic damage location

The concept of structural health monitoring has been introduced to ensure structural integrity during the design lifetime of a structure. The main objectives of structural health monitoring are to detect, locate, quantify, and predict any damage that occurs during this lifetime of the structure so that effective and efficient maintenance and...

Data-driven Decision Support for Component Flow Turnaround Time Reduction in Aircraft Maintenance: Case Study at KLM Engineering & Maintenance

Aircraft maintenance is inherently unpredictable due to differences in failure rates between components. This results in high variance inflow in repair shops, which in case of insufficient capacity yields long turnaround times and thus the need for additional components in stock. The aim of this research project is to determine the effect of...

Identification of Room Boundaries for Sound Field Estimation

Echoes generated by the sound reflected off the walls of a room carry information about the geometry of the enclosure. Capitalization of this acoustic property could lead to improvements in current state-of-the-art methods for sound field estimation, where prior information can be used to improve the conditioning of the problem. In this thesis,...

Formation flight in civil aviation

A model has been developed to demonstrate the value of a decentralized approach to formation flight routing. In the considered scenario, formation flight is an in-flight option. While centralized approaches are well covered in the literature, anticipating the use of formation flight before take-off, decentralized approaches have received less...

Design of a Combinatorial Tool for Preliminary Space Mission Analysis, applied to the GTOC2 Problem

In recent years, space missions to asteroids have been a focus of research. This type of mission has introduced a new challenge in space mission analysis: target selection. Indeed, given the large number of small Solar System bodies and their various orbital and physical characteristics, selecting a specific target is a rather complex task. This...

Counting sequences, Gray codes and lexicodes

A counting sequence of length n is a list of all 2^n binary n-tuples (binary codewords of length n). The number of bit positions where two codewords differ is called the Hamming distance of these two codewords. The average Hamming distance of a counting sequence of length n is defined as the average Hamming distance between the 2^n pairs of...