In-car usage-based insurance feedback strategies. A comparative driving simulator study

Usage-Based Insurances (UBI) enable policyholders to actively reduce the impact of vehicle insurance costs by adopting a safer and more eco-friendly driving style. UBI is especially relevant for younger drivers, who are a high-risk population. The effectiveness of UBI should be enhanced by providing in-car feedback optimised for individual drivers. Thirty young novice drivers were therefore invited to complete six experimental drives with an in-car interface that provided real-time information on rewards gained, their driving behaviour and the speed limit. Reward size was either displayed directly in euro, indirectly as a relatively large amount of credits, or as a percentage of the maximum available bonus. Also, interfaces were investigated that provided partial information to reduce the potential for driver distraction. Compared to a control no-UBI condition, behaviour improved similarly across interfaces, suggesting that interface personalisation after an initial familiarisation period could be feasible without compromising feedback effectiveness.

Practitioner Summary: User experiences and effects on driving behaviour of six in-car interfaces were compared. The interface provided information on driving behaviour and rewards in a UBI setting. Results suggest that some personalisation of interfaces may be an option after an initial familiarisation period as driving behaviour improved similarly across interfaces.     

Quasi-periodic variations of low energy cosmic rays

Cosmic rays(CR)play an important role in space weather-related studies.Their temporal variability,both of a quasi-periodic character as well as an irregular one,has been studied from ground-based direct measurements,as well as from cosmogenic nuclides,over a long time.We attempt to describe the current knowledge of selected quasi-periodicities in CR flux in the energy range above the atmospheric threshold,from direct measurements.The power spectrum density(PSD)of the CR time series as measured by neutron monitors(NMs)and by muon detectors has a rather complicated character.Along with the shape(slope)of the PSD,knowledge of the contribution of quasi-periodic variations(q-per)to the CR signal is of importance for the modulation,as well as for checking the links of CR to space weather,and/or to space climate effects.The rotation of the Earth and solar rotation cause two types of mechanisms behind the certain q-per observed in secondary CR on the Earth’s surface.Solar activity and solar magnetic field cyclicities contribute to the q-per signals in CR if studied over a longer time.The complexity of the spatial structure of the interplanetary magnetic field(IMF)and its evolution within the heliosphere,in addition to the changes in the geomagnetic field,cause variability in contributions of the q-per in CR.Wavelet spectra are useful tools for checking the fine structure of q-per and their temporal behaviour.Over a long time NMs and muon telescopes provide information about q-per in CR.     

Wavelet-based de-noising techniques in MRI

The paper deals with techniques for the enhancement of magnetic resonance (MR) images using the wavelet analysis, which is assessed from the viewpoint of choosing the mother wavelet and the thresholding technique. Three parameters are used as objective criteria of the quality of image enhancement: the signal-to-noise ratio (SNR), image contrast, and linear approximation of edge steepness. Unlike most of the standard methods, which work exclusively with image magnitude, we also examined the influence of image phase, i.e. the image is processed as a complex signal. In addition to the interpretation of results, a short summary is given that deals with the choice of the optimal mother wavelet and thresholding technique for different types of MR images.     

The ultimate equivalence problem for DOL systems

Summary The ultimate equivalence problem for DOL systems is shown to be recursively decidable. In algebraic formulation this problem can be stated as follows: Given finite alphabet , two homomorphisms h ₁ and h ₂ on the free monoid ^* and two words w ₁ w ₂ in ^*, does there exist m0 so that h ₁ ⁿ (w ₁) = h ₂ ⁿ (w ₂) for all nm?This research was supported by the National Research Council of Canada, Grant No. A7403, and most of it has been done during the author's stay at the University of Karlsruhe, Karlsruhe, Germany (Fed. Rep.)     

Resistive Bridging Defect Detection in Bulk,FDSOI and FinFET Technologies

Fully Depleted Silicon on Insulator (FDSOI) and Fin Field Effect Transistor (FinFET) are likely alternatives to traditional planar Bulk transistors for future technologies due to their respective promising ways of tackling the scalability issues with better short channel characteristics. Both these technologies are aiming in particular at regaining a better electrostatic control by the gate over the channel of the transistor. However, FDSOI is a planar MOS technology and as a result it is much more in continuity with planar Bulk as compared to the vertical FinFET transistors. The competition between these two technologies is fierce and many studies have been reported in the literature to compare these technologies in terms of speed performance, power consumption, cost, etc. However, these studies have not yet focused on their testability properties while the impact of defects on circuits implemented in FDSOI and FinFET technologies might be significantly different from the impact of similar defects in planar MOS circuit. It is therefore the objective of the paper to address this aspect. More specifically, we analyze the electrical behavior of logic gates in presence of a resistive bridging defect for these three different technologies. A particular care has been taken to design transistors and elementary gates in such a way that the comparative analysis in different technologies is meaningful. After implementing similar design in each technology, we compare the electrical behavior of the circuit with the same resistive bridging defect and we analyze both the static and dynamic impact of this defect.     

A multi-level wave based numerical modelling framework for the steady-state dynamic analysis of bounded Helmholtz problems with multiple inclusions

The Wave Based Method (WBM) is an alternative numerical prediction method for both interior and exterior steady-state dynamic problems, which is based on an indirect Trefftz approach. It applies wave functions, which are exact solutions of the governing differential equation, to describe the dynamic field variables. The smaller system of equations and the absence of pollution errors make the WBM very suitable for the treatment of Helmholtz problems in the mid-frequency range, where element-based methods are no longer feasible due to the associated computational costs. A sufficient condition for convergence of the method is the convexity of the considered problem domain. As a result, only problems of moderate geometrical complexity can be considered and some geometrical features cannot be handled at all. In this paper, these limitations are alleviated through the development of a general modelling framework based on existing WBM methodologies which allows for the efficient introduction of inclusion configurations in bounded WBM models for problems governed by one or more Helmholtz equations. The feasibility and efficiency of the method is illustrated by means of numerical verification studies in which the methodology is applied to two types of dynamic problems. On the one hand, a single Helmholtz equation associated with the steady-state dynamic behaviour of acoustic cavities is studied. On the other hand, the framework is applied to the solution of the Navier system of partial differential equations that describe the elastodynamic response of two-dimensional perforated solids.     

An ontology‐based framework for automatic topic detection in multilingual environments

The detection of topics from large textual data volumes is currently a research area, which has many applications in the development of computational systems. A proposed solution for the detection of topics in data mining is the application of clustering methods. This paper presents the application of a new ontology‐based methodology for the automatic topic detection without any previous information based on the use of hierarchical clustering algorithms and a multilingual knowledge base. The approach also includes lexical resources that allow us to enrich the semantics of the analyzed texts. The novelty of this approach consists of the dimensionality reduction of the terms present in the texts by using ontology and the introduction of a method for the creation of a term weight matrix for use in clustering algorithms. With this approach, it is possible to improve automatic topic detection in documents. The proposed methodology was assessed with four datasets (two of them in English and two in Spanish).     

The effect of crosslinking on properties of polyurethane elastomers

A series of segmented polyurethanes from two polyols, 4,4′-diphenylmethane diisocyanate (MDI) and butane diol was synthesized. The degree of chemical crosslinking was controlled by varying the ratio of poly(oxypropylene) diol to poly(oxypropylene/oxyethylene) triol. The samples were prepared at the stoichiometric ratio of NCO to OH groups and at a constant concentration of hard segments (butane diol; MDI) equal 50 wt %. At low concentrations of the triol the molecular weight of the polyurethanes increases; at higher concentrations (above 9 mol %) crosslinked products are obtained. All samples show a distinct two-phase structure and in the region of 0–150°C the dynamic mechanical behavior is affected by the hard phase. Chemical crosslinking was found to increase the tensile strength and strain at break, but did not affect appreciably the tear strength, hardness, and soft segment glass transition. The stress relaxation rate at room temperature was found to depend both on the elongation and on the degree of crosslinking. A comparison of the sol fractions w_s found for crosslinked samples with the predictions of the theory of branching processes proved that the achieved conversions of reactive groups in networks are high (～ 0.98).