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For the spatial reconstruction of a two phase flow, as it might occur in a pipe, the main problem has always been the blurring of the resulting images.

In this paper, we present a method where blurring is implicitly avoided by the use of level sets. The level set method describes the iteratively evolving interface between different materials. The underlying field problem is solved with the boundary element method formulated in the region, where the degrees of freedom are present and the finite element method in all other regions.

Finally reconstruction results of an electrical capacitance tomography sensor are presented to show the validity of the method.

Presents a method where blurring is avoided by the use of level sets.

The accurate simulation of battery cells is of growing interest in automotive industry especially in hybrid vehicle technology. Conventional lumped parameter models are not able to predict the battery voltage accurately. Thus models describing the physics of the battery cell are searched. In this paper a model consisting of six partial differential equations is proposed, which predicts the state of charge (SOC) and the battery voltage for given charge and discharge current densities.

In this chapter we interpret traffic safety culture (TSC) in terms of data on beliefs, attitudes, and behaviors from the fourth wave of the SARTRE study to find out whether they can be interpreted in a perspective. The SARTRE study is a European-wide survey that started in 1991 and collects information on mobility, risk perceptions, attitudes, behaviors, and experiences on the road (Cauzard, 1998, 2004; Cestac & Delhomme, 2012). The chapter focuses on the group of car drivers.

A principal component factor analysis was conducted to explore the underlying structure of the data set. Results suggest an underlying structure of five components which explain more than 55% of the variance. These dimensions were labeled (1) acceptance of technology and enforcement, (2) risk attitudes, (3) experienced and self-exerted behavioral control, (4) personal concern, (5) perception of other road users’ safety performance.

The influence of these five factors on safety performance (fatality rates) was estimated by regression analysis. Results show that only the second factor (risk attitudes) has a significant effect on fatality rates. As a consequence, expressive and instrumental attitudes about risk-taking should be addressed in driver training as well as information campaigns in order to improve safety culture at the level of individual car drivers.

Considers, without loss of generality, a simple linear problem, where in a certain domain the magnetic field, generated by infinitely long conductors, whose locations as well as the currents are unknown, has to meet a certain figure. The problem is solved by applying hierarchical simulated annealing, which iteratively reduces the dimension of the search space to save computational cost. A Gauss‐Newton scheme, making use of analytical Jacobians, preceding a sequential quadratic program (SQP), will be applied as a second approach to tackle this severely ill‐posed problem. The results of these two techniques will be analyzed and discussed and some comments on future work will be given.

Electrical impedance tomography (EIT) is a non‐invasive method to monitor conductivity changes in regions of the human body. Its robust, miniaturizable instrumentation makes EIT particularly suitable for online‐monitoring without too much inconvenience for the patient. A major methodological problem is the poor quality of the conductivity images, which is due to the low spatial resolution and low sensitivity for structures far away from the object’s surface as well as large qualitative errors in the reconstructed conductivity values. This paper outlines the advantages of multi‐frequency EIT for a simple two‐dimensional model. In the first part of the paper we assume that some a priori information from MR images is at hand, providing good starting values for the reconstruction process, while in the second part it is assumed that no a priori information about regions of different material values is available.

Previous studies have shown how the nature of businesses and the strategies pursued by their owners are affected by the personality traits of their owners. These personality traits can be formed in the early stages of life due to experiences and the surrounding context, where religion is a particularly important aspect of this context. This study aims to explore how religion affects entrepreneurial activities through the personality traits created.

This study uses interviews with 43 Muslim entrepreneurs in Scotland to examine the role played by religion. This ensures that the national institutional context is kept consistent but also allows an in-depth examination of relationships, which are likely to be interlinked and recursive.

The traits created influence the nature of the entrepreneurial activities undertaken with the potential to harm and support the entrepreneurial endeavours. It is the combination of personality traits that are formed which have the greatest effect. As such, it is found that Muslim entrepreneurs display less openness and creativity associated with new ideas, but this does not reflect risk aversion rather hard work in itself is valued, and patience combined with an external locus of control mean entrepreneurial behaviours are not altered to boost poorly performing business activities.

For Muslim entrepreneurs in Scotland, their traits explain why growth may not be a foremost consideration of these entrepreneurs rather they may value hard work and meeting the ideals of formal and informal institutions associated with religion. For those seeking to support minority groups through the promotion of entrepreneurship, either they must seek to overcome these ingrained traits or alter support to complement the different objectives held by Muslim entrepreneurs.

Following the recent surge in research on carsharing, the paper synthesizes this growing literature to provide a comprehensive understanding of the current state of research and to identify directions for future work. Specifically, this study details implications for service theory and practice.

Systematic selection and analysis of 279 papers from the existing literature, published between 1996 and 2020.

The literature review identified four key themes: business models, drivers and barriers, customer behavior, and vehicle balancing.

For managers, the study illuminates the importance of collaboration among stakeholders within the automotive sector for purposes of widening their customer base and maximizing utilization and profits. For policy makers, their important role in supporting carsharing take-off is highlighted with emphasis on balancing support rendered to different mobility services to promote mutual success.

This is the first systematic multi-disciplinary literature review of carsharing. It integrates insights from transportation, environmental, and business studies, identifying gaps in the existing research and specifically suggesting implications for service research.

Nonlinear solution approaches for inverse problems require fast simulation techniques for the underlying sensing problem. In this work, the authors investigate finite element (FE) based sensor simulations for the inverse problem of electrical capacitance tomography. Two known computational bottlenecks are the assembly of the FE equation system as well as the computation of the Jacobian. Here, existing computation techniques like adjoint field approaches require additional simulations. This paper aims to present fast numerical techniques for the sensor simulation and computations with the Jacobian matrix.

For the FE equation system, a solution strategy based on Green’s functions is derived. Its relation to the solution of a standard FE formulation is discussed. A fast stiffness matrix assembly based on an eigenvector decomposition is shown. Based on the properties of the Green’s functions, Jacobian operations are derived, which allow the computation of matrix vector products with the Jacobian for free, i.e. no additional solves are required. This is demonstrated by a Broyden–Fletcher–Goldfarb–Shanno-based image reconstruction algorithm.

MATLAB-based time measurements of the new methods show a significant acceleration for all calculation steps compared to reference implementations with standard methods. E.g. for the Jacobian operations, improvement factors of well over 100 could be found.

The paper shows new methods for solving known computational tasks for solving inverse problems. A particular advantage is the coherent derivation and elaboration of the results. The approaches can also be applicable to other inverse problems.