TY  - JOUR
A1  - Grajewski, Matthias
A1  - Kleefeld, Andreas
T1  - Detecting and approximating decision boundaries in low-dimensional spaces
JF  - Numerical Algorithms
N2  - A method for detecting and approximating fault lines or surfaces, respectively, or decision curves in two and three dimensions with guaranteed accuracy is presented. Reformulated as a classification problem, our method starts from a set of scattered points along with the corresponding classification algorithm to construct a representation of a decision curve by points with prescribed maximal distance to the true decision curve. Hereby, our algorithm ensures that the representing point set covers the decision curve in its entire extent and features local refinement based on the geometric properties of the decision curve. We demonstrate applications of our method to problems related to the detection of faults, to multi-criteria decision aid and, in combination with Kirsch’s factorization method, to solving an inverse acoustic scattering problem. In all applications we considered in this work, our method requires significantly less pointwise classifications than previously employed algorithms.
KW  - MCDA
KW  - Inverse scattering problem
KW  - Fault approximation
KW  - Fault detection
Y1  - 2023
SN  - 1572-9265
N1  - Corresponding author: Matthias Grajewski
VL  - 93
IS  - 4
PB  - Springer Science+Business Media
CY  - Dordrecht
ER  - 
TY  - JOUR
A1  - Schopen, Oliver
A1  - Shah, Neel
A1  - Esch, Thomas
A1  - Shabani, Bahman
T1  - Critical quantitative evaluation of integrated health management methods for fuel cell applications
JF  - International Journal of Hydrogen Energy
N2  - Online fault diagnostics is a crucial consideration for fuel cell systems, particularly in mobile applications, to limit downtime and degradation, and to increase lifetime. Guided by a critical literature review, in this paper an overview of Health management systems classified in a scheme is presented, introducing commonly utilised methods to diagnose FCs in various applications. In this novel scheme, various Health management system methods are summarised and structured to provide an overview of existing systems including their associated tools. These systems are classified into four categories mainly focused on model-based and non-model-based systems. The individual methods are critically discussed when used individually or combined aimed at further understanding their functionality and suitability in different applications. Additionally, a tool is introduced to evaluate methods from each category based on the scheme presented. This tool applies the technique of matrix evaluation utilising several key parameters to identify the most appropriate methods for a given application. Based on this evaluation, the most suitable methods for each specific application are combined to build an integrated Health management system.
KW  - Fuel cell
KW  - Health management system
KW  - Online diagnostic
KW  - Fault detection
KW  - Non-model-based Evaluation
Y1  - 2024
U6  - https://doi.org/10.1016/j.ijhydene.2024.05.156
SN  - 0360-3199
VL  - 70
SP  - 370
EP  - 388
PB  - Elsevier
CY  - Amsterdam
ER  -