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Weggebruikers gaan niet bepaald efficiënt om met de informatie die hun wordt aangereikt, zoveel heeft wetenschappelijk onderzoek naar het reizigersgedrag wel aangetoond. Wetenschappers spreken in dit verband van inertie – een zekere traagheid in het verwerken en gebruiken van nieuwe informatie. Voor zijn proefschrift The Dynamics of User Perception, Decision Making and Route Choice onderzocht Jaap Vreeswijk de achtergronden van inertie bij keuzegedrag. In deze bijdrage lichten Vreeswijk en zijn promotors Van Berkum en Van Arem de belangrijkste resultaten toe.

The EU FP7 project eCoMove created an integrated solution for more energy efficient road transport based on cooperative technology. The project's core concept assumed that there is theoretical minimum energy consumption achievable with the "perfect eco-driver" travelling through the "perfectly eco-managed" road network. Microscopic traffic flow simulation played an important role for the assessment of traffic efficiency and energy efficiency as only a few vehicles could be equipped with the eCoMove System in the real world. The simulations were performed for different test sites, application combinations, traffic demands and penetration rates. This paper gives an overview of the test sites, the traffic management applications, the simulation environment used and presents conclusions from the simulation studies.

Although travel time is probably one of the most important attributes in route choice, the shortest time route is often not the preferred route according to several studies in the literature. This study tries to explain this finding by testing the hypotheses that choice makers may be able to estimate travel times correctly for routes they prefer, but that they are biased against alternatives even if these are faster. For a few choice sets of routes in the Dutch city of Enschede, respondents were asked to choose a route and provide their estimated travel times for both the preferred and alternative routes. These travel times were then compared with actual travel times. The comparison confirmed the hypotheses. In only 41% of the cases the shortest time route was chosen. Travel times were generally overestimated while respondents on average overestimated travel times of non-chosen routes more than the travel times of chosen routes. Besides, familiar routes, orbital routes and most direct routes were preferred even when they had a higher travel time. These results show that drivers are not able or do not want to evaluate routes objectively which has important implications for traffic management practices.

This paper describes the results of the verification and validation of the ecoStrategic Model, which was developed, implemented and tested in the eCoMove project. The model uses real-time and historical traffic information to determine the current, predicted and desired state of traffic in a network. The model was implemented for the city of Helmond, the Netherlands. The validation focused on two questions: (1) does the model realistically and accurately predict the traffic situation 15 minutes ahead, so that traffic management measures may be taken when necessary, and (2) does the desired state, which minimizes the environmental costs, result in lower overall CO2 emissions

In het Europese project eCoMove werken 32 partners uit tien landen aan slimme, coöperatieve oplossingen om het verkeer energiezuiniger te maken. Welk concept hanteren de partners? En welke concrete applicaties hebben de eCoMove-partners inmiddels ontwikkeld

This paper presents the eco-Strategic Model (eStraM), one of the core technologies being developed within the eCoMove project (EU 7th Framework). eCoMove aims to tackle the problem of energy efficiency in road transport by applying the latest vehicle-to-infrastructure and vehicle-to-vehicle communication technologies, to create an integrated solution comprising cooperative eco-driving support and eco-traffic management. eStraM, a part of the eCoMove system, is a network model that provides current and predicted information about hotspot events for congestion and CO2 emissions or locations that have a major impact on CO2 emissions. It is a basis for applications such as traffic management and control and it may also be used by in-vehicle and back office applications

In april 2010 is het driejarige EU-project eCoMove gestart, waarin automobielfabrikanten, wegbeheerders, de verkeersindustrie en de onderzoekswereld samenwerken om coöperatieve systemen te ontwikkelen die het brandstofverbruik met 20% kunnen verminderen. Er worden applicaties ontwikkeld die het verkeer op zo efficiënt mogelijk wijze door het netwerk geleiden en applicaties die bestuurders van personen- en vrachtauto’s tijdens het rijden ondersteunen. Daarnaast worden ook applicaties ontwikkeld waarmee vervoerders milieuvriendelijker hun ritten kunnen plannen en applicaties waarmee bestuurders voor of na een verplaatsing kunnen bekijken hoe ze hun rijgedrag verder kunnen optimaliseren. Deze bijdrage gaat dieper in op de eCoMove applicaties die de Nederlandse partners zullen (helpen) ontwikkelen. De applicaties zijn bedoeld voor zowel het stedelijke- als het snelwegennet en maken gebruik van voertuig-voertuig en voertuiginfrastructuurcommunicatie. Aandachtspunten bij de ontwikkeling zijn trade-offs tussen brandstofverbruik en overige doelen, en trade-offs tussen systeem- en individuele doelen.

A European project using volunteer drivers and placing them in different driving scenarios in a simulated environment is making pioneering efforts to improve safety for all road users at intersections

Voor de invoering van coöperatieve voertuig-wegkantsystemen in Europa leggen drie grote en gei'ntegreerde Europese onderzoeksprojecten de basis: CVIS, Safespot en Coopers. Nederlandse overheden en bedrijven zijn hierin goed vertegenwoordigd en lopen voorop in de ontwikkeling van coöperatieve technologieën en toepassingen in mobiliteit. Vanaf zoo6 is in Europese projecten de basistechnologie ontwikkeld die vanaf zoog op grote schaal getest en aan een breder publiek getoond zal worden. Belangrijke evenementen zijn het r6th ITS World Congress in Stockholm in september van dit jaa¡ een Europese Coöperatieve Systemen Showcase in zoro in Nederland (in voorstelfase) en een demonstratie-evenement 'Cooperative Systems on the Road' in Helmond 1n mei van dit jaar (www.testsiteheimond.org). Omvangrijke Europese onderzoeksprojecten hebben coöperatieve systemen op de kaart gezet. Het echte werk, invoerlng en gebruik, kan nu beginnen!

This paper describes the Human-Machine-Interface (HMI) design approach for the integration of several cooperative systems that were developed in the projects CVIS and SAFESPOT. In this design approach, several important issues for integrated HMI were accounted for: the prioritization of the information for the highest safety relevance, the timing of the warning, and presenting the information in such way that the driver will act intuitively in the proper way and timely instant. The HMI design has been demonstrated at the Helmond test site. Experts have evaluated two applications (intersection and a lane-change application). The acceptance was rated positive for both systems, the trust in the systems was rated as adequate and the visual and acoustic warnings were rated as fairly easy to understand. In addition, the tactile and haptic warnings were rated as easier to understand compared to the visual/acoustic warnings. These results provide input for ongoing HMI design for cooperative systems.

This paper describes the Human-Machine-Interface (HMI) design approach for the integration of several cooperative systems that were developed in the projects CVIS and SAFESPOT. In this design approach, several important issues for integrated HMI were accounted for: the prioritization of the information for the highest safety relevance, the timing of the warning, and presenting the information in such way that the driver will act intuitively in the proper way and timely instant. The HMI design has been demonstrated at the Helmond test site. Experts have evaluated two applications (intersection and a lane-change application). The acceptance was rated positive for both systems, the trust in the systems was rated as adequate and the visual and acoustic warnings were rated as fairly easy to understand. In addition, the tactile and haptic warnings were rated as easier to understand compared to the visual/acoustic warnings. These results provide input for ongoing HMI design for cooperative systems.

About forty percent of all accidents occur at intersections. The Intelligent Cooperative Intersection Safety system (IRIS), as part of the European research project SAFESPOT, is a roadside application and aims at minimizing the number of accidents at controlled and uncontrolled intersections. IRIS uses vehicle-to-infrastructure communication to track and analyze the movements of all individual vehicles. A key element of IRIS is to identify dangerous situations in time and take the appropriate measure to prevent collisions. This paper presents the concept of IRIS, points out the complexity of intersections and addresses the usefulness and results of a driving simulator study. KEYWORDS Intersection safety, SAFESPOT, IRIS, Cooperative, Vehicle-to-Infrastructure, Roadside application, Driving simulator, Driver behaviour, Human Factors

The aim of the present study was to investigate the interaction between salts of fatty acids (FAS) and elastin. Absorption of fatty acids in elastin may affect the elasticity of elastin-containing tissue. Such phenomena could, for instance, be of relevance for the understanding of the formation of atherosclerotic plaque in blood vessel walls.Chapter I gives a general introduction on the relevance of this study and an outline of the thesis. Furthermore, it contains information on the characteristics of both elastin and FAS.In chapter 2, experiments are discussed that give insight into the absorption mechanism. Elastin from bovine ligamentum nuchae was exposed to solutions of FAS having hydrocarbon chain lengths varying between 12 and 16 carbon atoms. The amount absorbed was determined gravimetrically. The uptake of FAS can be described by a second order mechanism, in which the absorption rate depends on the concentration of FAS in solution and the number of absorption sites in elastin, and in which the desorption depends on the number of occupied sites. Competitive absorption experiments showed that the absorption rate constant decreases with increasing chain length. The binding of FAS is reversible. Therefore it is allowed to calculate the standard Gibbs energy,Δ abs G 0 of the absorption process from the absorption isotherms. The affinity of the FAS for elastin is predominantly determined by hydrophobic interaction. The value forΔ abs G 0 per CH 2 group in the FAS is -0.8±0.2kJ/mol. This is much smaller thanΔ abs G 0 for the transfer of CH 2 from an aqueous to a nonaqueous environment (-4kJ/mol). The difference may be explained by the fact that the FAS monomers that bind to elastin are released from micelles in solution. Although under the experimental condition of pH= 10 where the experiment have been carried out, the overall electric charge in elastin is negative, the contribution from the negatively charged head group of the FAS toΔ abs G 0 is attractive and equal to about - 3k.J/mol. This suggests electrostatic attraction between FAS with positively charged groups, such as the desmosine and isodesmosine cross-links in elastin.Binding of FAS is accompanied by co-absorption of salt (NaCl) and solvent in the elastin. The former results in an osmotic pressure between the elastin sample and the surrounding solution. This pressure increases as the salt concentration and/or the chain length of the FAS increases. The uptake of solution partly occurs to compensate for the electrostatic repulsion between the negatively charged groups of FAS in elastin. The swelling and, hence, the absorption of FAS is limited by the cross-linking of elastin. Due to the presence of OH- ions and absorbed FAS, degradation of elastin occurs, resulting in a decrease in cross-link density which, in turn promotes the uptake of more FAS. The rate of cross-link rupture is proportional to the osmotic pressure, both are larger for FAS with a longer chain. The inference is that the degradation of elastin is enhanced by the internal osmotic pressure.Elastin is a network of randomly coiled polypeptide chains displaying rubber-elastic proper-ties. In chapters 3, 4 and 5 the influence of FAS on the rubber elasticity is studied.In chapter 3, the change in elasticity modulus, which is the retractive force per unit cross-sectional area, is considered. The modulus depends on the number of cross- links per unit volume of elastin. Because of the degradation of elastin, caused by FAS uptake, the number of crosslinks and hence, the elasticity modulus decrease. The degradation rate increases with increasing chain length of the absorbed FAS. In addition, FAS may also change the rheological character of elastin. After a relatively long incubation time, depending on the water content and temperature, FAS may induce a change from a pure rubber-like into viscoelastic behaviour.The influence of FAS on the conformational distribution of the chains in the network is discussed in chapter 4. The end-to-end length of the polypeptide chains does not change significantly upon FAS absorption, provided that the samples retain their rubber-elastic character. In the case of viscoelastic behaviour, no inference about the conformational properties of the chains could be made. Furthermore, the dependency of the conformational distribution on the temperature is hardly affected by FAS absorption. These results imply that the rotational freedom of the polypeptide chain is not significantly affected. The inference is made that the FAS molecules do not bind directly to the polypeptide units in the main chain, but rather to the (hydrophobic) side groups. It is also possible that FAS molecules bind to the cross- links, either through hydrophobic interaction with the alkyl groups and/or through electrostatic interactions with the positively charged quaternary ammonium group of the desmosine or isodesmosine units.Upon lowering the temperature, the number of accessible conformations of the polypeptide chain decreases, which results in a rubberglass transition over a relatively narrow temperature range. The transition temperature (T g ) decreases with increasing water content in elastin. This can be explained by the reduction of intermolecular interactions and therefore by an increase of the rotational freedom at higher water content. As it was concluded that the rotational freedom of the polypeptide chains is not affected by absorption of FAS, no influence of FAS on T g is expected. In chapter 5, this expectation was confirmed. Binding of FAS does not directly influence the T g . However, since absorption of FAS causes swelling of the elastin network, and, therefore increases the uptake of water, binding of FAS indirectly causes a shift of T g towards lower values.The most important conclusion concerning the interaction between FAS and elastin is that the direct influence of FAS on the elastic properties is very small. However, since FAS absorption is attended by swelling of the network and degradation of elastin, FAS absorption changes the rubber-elastic properties indirectly. The influence of the FAS is larger for longer chain length.