La sortie de route est l’une des causes principales des accidents. En dehors de l’inattention du conducteur, elle est principalement due à une vitesse inadaptée, que ce soit par rapport aux limites légales de vitesses ou à l’environnement. Or les systèmes visant à alerter le conducteur de dépassements de la limite ou à le contraindre à une certaine vitesse existent et ont un impact positif sur les accidents. Cependant, ils n’ont pas encore atteints la maturité de systèmes d’assistance agissant en fonction de toutes les conditions de conduite. Cette thèse a pour objet d’étudier le risque intégré de sortie de route et donc de développer un système d’alerte à des vitesses excessives qui permet de déterminer la vitesse limite en fonction de toutes les conditions extérieures (environnement, infrastructure), du comportement du conducteur et de la dynamique du véhicule. Pour atteindre cet objectif, nous proposons de définir les différents facteurs de l’infrastructure, de l’environnement, du véhicule et du conducteur, limitant la vitesse. Certains de ces facteurs sont mesurables, les autres seront estimés par des observateurs. Ainsi, nous établirons des relations entre ces facteurs et la vitesse du véhicule en se basant sur des modèles mathématiques. Ces modèles nous permettront de définir des facteurs d’ajustement d’une vitesse de référence. La vitesse ajustée pourra ensuite être utilisée soit pour alerter le conducteur dans un système d’assistance, soit pour évaluer les limites existantes. Un modèle de véhicule étant nécessaire à la synthèse des observateurs et à la qualification de la dynamique véhicule, nous avons opté pour le modèle à quatre roues. Le filtre de Kalman étendu a été utilisé comme technique d’estimation. Pour le développement théorique du système d’alerte, nous utilisons le profil de la SAVV comme vitesse de référence après quelques améliorations. Ensuite, plusieurs modèles mathématiques sont utilisés pour lier la vitesse aux autres facteurs influents. Le système développé a été implanté sous SimuLink/MatLab et nous avons pu présenter quelques scenarios pratiques. Enfin, des expérimentations en temps réel sur un véhicule prototype du LIVIC ont permis de valider les résultats des simulations. / Run-off-road risk is one of the main accidents type. Apart from the driver inattention, it is mainly due to an unsuitable speed, whether to the legal speeds limits or the environment. However systems aiming to alert the driver of exceeding the limit or to force him to maintain a certain speed exist and have a positive impact on the accidents. However, they did not reach yet the maturity of assistance systems acting according to all the driving conditions. The objective of this thesis is to study the run-off-road risk and thus to develop an alert system for excessive speeds which is able to determine the speed limit according to all the external conditions (environment, infrastructure), the driver behavior and the vehicle dynamics. To achieve this goal, we propose to define the various factors of the infrastructure, the environment, the vehicle and the driver, limiting speed. Some of these factors are measurable; the others will be estimated by observers. Thus, we will establish relations between these factors and the vehicle speed based on mathematical models. These models will serve to define adjustment factors of a reference speed. Adjusted speed could then be used either to alert the driver in an assistance system, or to evaluate the existing limits. A vehicle model being necessary for the observer’s synthesis and the qualification of vehicle dynamics, we chose the four wheels vehicle model. The Extended Kalman filter was used as an estimation technique. For the theoretical development of the alert system, we use the SAVV speed profile as a reference speed after some improvements. Then, several mathematical models are used to bind speed to the other influential factors. The developed system was established under SimuLink/MatLab and we could present some practical scenarios. In addition, real-time experimentations on a LIVIC prototype vehicle are made and allowed to validate the simulations results.

Th.--Droit--Paris 1, 1984.

A comprehensive examination of the process of determining locations for river crossings constitutes the basic subject of this thesis. This process is highly complex and involves a variety of interrelated governmental and technical problems. The various financial and administrative responsibilities of the three levels of Canadian government provide a complicated operational framework within which river crossings and other transportation facilities are located and constructed. Similarly, inter-related locational criteria, such as land use and transportation needs and engineering requirements, pose formidable problems for the design and location of transportation facilities. In order that these inter-related problems are coped with effectively, it is proposed: That in Canada, the Provincial Government should use a comprehensive planning approach, within a framework of intergovernmental participation, to determine the location of river crossings within the Provincial highway system. The investigation is limited in scope to an analysis of river crossings that are the constitutional responsibility of the Provincial Governments in Canada. Reference is made to the financing and administration of transportation facilities in British Columbia for purposes of illustration. The administration and financing of highways is discussed in some detail since highways form the physical and functional framework for the planning of river crossings. The term "river crossing" is defined as a bridge or tunnel structure crossing any water barrier. An examination is made of the three levels of governmental responsibilities respecting transportation planning and of the need for inter-governmental participation during the process of determining river crossing locations. The examination includes a discussion of the relationship between the role of "executive authority" and the various financial and administrative responsibilities of the Federal, Provincial and Municipal Governments. It is concluded that because of its constitutional responsibilities respecting land use planning and highways, and its dominant financial role in the provision of highway facilities, the Provincial Government should act as the executive authority in the process of determining locations for Provincial river crossings. Regardless, however, of the financial arrangements between levels of government, there should be inter-governmental administrative participation during the process of locating river crossings. In particular, Municipalities having been delegated the responsibility for community planning should be given the opportunity to integrate proposed highway and river crossing facilities with local land use and transportation plans. It is suggested that a comprehensive planning approach provides for the consideration of all major governmental and technical factors pertinent to the location selection process. It is assumed that the transportation planning process for determining the design and location of overall transportation systems is basic to the comprehensive planning approach. An examination of the locational criteria related to river crossings confirms the need to consider all significant factors when determining locations for river crossings. A framework for location selection is developed in order to implement the comprehensive planning approach and to apply effectively the locational criteria to location selection problems. A case study investigation tests the validity of the hypothesis and the effectiveness of the framework for location selection. The case study concerns the process of determining a location for a Fraser River crossing in the Metropolitan Vancouver, B.C. area nine years ago. The decision to locate a tunnel crossing at Deas Island is evaluated in retrospect through the application of the location selection framework to the overall Fraser River crossing problem. From the case study analysis, it is concluded that the hypothesis proposed in this thesis is basically valid. The Provincial Government, because of its constitutional and financial responsibilities, should act as the executive authority in determining river crossing locations within the Provincial highway system. Inter-governmental participation, especially administrative, is essential to the integration of Federal, Provincial and Municipal transportation and land use functions. The use of the comprehensive planning approach and its related framework for location selection facilitates the consideration of all significant factors pertinent to the determination of river crossing locations. However, the comprehensive planning approach should be so defined as to include broad transportation and land use policies which would serve as basic guidelines in the process of determining river crossing locations. / Applied Science, Faculty of / Community and Regional Planning (SCARP), School of / Graduate

Texte remanié de: Th. doct.--Droit privé--Perpignan, 1998. / Bibliogr. p. 427-446. Index.

People in unfamiliar environments often need navigation guidance to reach a destination. Research has found that compared to outdoors, people tend to lose orientation much more easily within complex buildings, such as university buildings and hospitals. This paper proposes a category-based method to generate landmark-based route instructions to support people's wayfinding activities in unfamiliar indoor environments. Compared to other methods relying on detailed instance-level data about the visual, semantic, and structural characteristics of individual spatial objects, the proposed method relies on commonly available data about categories of spatial objects, which exist in most indoor spatial databases. With this, instructions like "Turn right after the second door, and use the elevator to go to the second floor" can be generated for indoor navigation. A case study with a university campus shows that the method is feasible in generating landmark-based route instructions for indoor navigation. More importantly, compared to metric-based instructions (i.e., the benchmark for indoor navigation), the generated landmark-based instructions can help users to unambiguously identify the correct decision point where a change of direction is needed, as well as offer information for the users to confirm that they are on the right way to the destination.

No description available.

Thesis (Ph. D.)--Purdue University, 2005. / Includes bibliographical references (p. 186-196). Also available online.

The sequential aldol reactions of thiopyran derivatives 112 and 119 to rapidly generate hexapropionate building blocks in two carbon-carbon forming steps has been well studied within the Ward group. An extension of this strategy to generate non-racemic tetra- and hexapropionate fragments involved the use of non-racemic 119 which was obtained via resolution of the acid derivate 131. <p> Part of the present work concerns the preparation of non-racemic 119 via enantioselective protonation of various thiopyran based ester derivatives. The trend observed in the ee obtained for the various ester derivatives is consistent with what has been previously observed by other groups. <p> Section 2.3 discusses the use of β-ketocarbonyl analogues of thiopyranone in vinylogous aldol reactions. A β-ketocarbonyl analogue was prepared and shown to undergo stereoselective aldol reactions under previously established condtions. The stereoselectivities of the reactions were in all cases consistent with what has been previously observed for the aldol reactions of 112 and 119 within the group. <p> Section 2.4 discusses the preparation of a meso dialdehyde derivative of thiopyranone (196) and its use in a simultaneouse two directional aldol reaction to generate a hexapropionate building block with six stereocenters in a one pot reaction. The meso adduct 202as generated was successfully desymmetrized via enantioselective enolization to afford an enantioenriched adduct with seven stereogenic centers. <p> The meso dialdehyde 196 was also desymmetrized via an enantiotopic group selective aldol reaction promoted with (S)-proline. This reaction proceeds via a dynamic kinetic and thermodynamic resolution to afford a single stereoisomer. The enantioenriched aldol adduct was converted to a tetrapropionate unit and also demonstrated after derivatization to undergo a second aldol reaction affording a non-racemic hexapropionate synthon. This chemistry is discussed in section 2.5. <p> Section 2.6 discuses the assignment of the relative and absolute configurations of the various aldol adducts via NMR and X-ray. <p> To demonstrate the synthetic usefulness of this research, the hexapropionate synthon 202as was used as a template towards the confirmation or reassignment of the core spiroketal structure reported for enteridic acid.

The sequential aldol reactions of thiopyran derivatives 112 and 119 to rapidly generate hexapropionate building blocks in two carbon-carbon forming steps has been well studied within the Ward group. An extension of this strategy to generate non-racemic tetra- and hexapropionate fragments involved the use of non-racemic 119 which was obtained via resolution of the acid derivate 131. <p> Part of the present work concerns the preparation of non-racemic 119 via enantioselective protonation of various thiopyran based ester derivatives. The trend observed in the ee obtained for the various ester derivatives is consistent with what has been previously observed by other groups. <p> Section 2.3 discusses the use of β-ketocarbonyl analogues of thiopyranone in vinylogous aldol reactions. A β-ketocarbonyl analogue was prepared and shown to undergo stereoselective aldol reactions under previously established condtions. The stereoselectivities of the reactions were in all cases consistent with what has been previously observed for the aldol reactions of 112 and 119 within the group. <p> Section 2.4 discusses the preparation of a meso dialdehyde derivative of thiopyranone (196) and its use in a simultaneouse two directional aldol reaction to generate a hexapropionate building block with six stereocenters in a one pot reaction. The meso adduct 202as generated was successfully desymmetrized via enantioselective enolization to afford an enantioenriched adduct with seven stereogenic centers. <p> The meso dialdehyde 196 was also desymmetrized via an enantiotopic group selective aldol reaction promoted with (S)-proline. This reaction proceeds via a dynamic kinetic and thermodynamic resolution to afford a single stereoisomer. The enantioenriched aldol adduct was converted to a tetrapropionate unit and also demonstrated after derivatization to undergo a second aldol reaction affording a non-racemic hexapropionate synthon. This chemistry is discussed in section 2.5. <p> Section 2.6 discuses the assignment of the relative and absolute configurations of the various aldol adducts via NMR and X-ray. <p> To demonstrate the synthetic usefulness of this research, the hexapropionate synthon 202as was used as a template towards the confirmation or reassignment of the core spiroketal structure reported for enteridic acid.

Texte remanié de: PhD--University of Westminster, 1998. / Glossaire. Bibliogr. p. 251-258. Index.