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KEY TECHNOLOGIES IN DEVISING AUTONOMOUS VEHICLE LOCATION AND NAVIGATION SYSTEMFei, Peng, Pingfang, Zheng, Qishan, Zhang, Zhongkan, Liu 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / In this paper, a devising scheme of Autonomous Vehicle Location and Navigation System
is introduced firstly. Then, several key technologies used in the devising scheme are
presented, which includes a data fusion method based on extended decentralized kalman
filter technology, a map-matching method used to compensate the positioning error, and a
digital map data processing method used to realize route planning algorithm. By this
time, a sample machine based on the devising scheme introduced in this paper has
already been worked out successfully. The availability and the advantages of these
technologies have been demonstrated.
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OPTIMAL ENERGY-DELAY ROUTING PROTOCOL WITH TRUST LEVELS FOR WIRELESS AD HOC NETWORKSTaqieddin, Eyad 10 1900 (has links)
ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / An ad hoc network is a group of wireless nodes which do not rely on any fixed infrastructure. Hosts cooperate by forwarding packets for each other to communicate with nodes that are out of the radio transmission range. We propose a new routing algorithm that is based on the concept of multipoint relay nodes (MPR). The main focus of the Trust Level Routing protocol is the reliability and survivability of the network by applying costs to each MPR candidate. The cost calculation is based on the delay incurred, energy available at the MPR node, energy spent during transmission and number of packets sent on each link. We highlight the vulnerabilities in current link state routing algorithms and propose the use of light weight encryption algorithms to achieve a dependable routing algorithm. Network simulator (ns-2) is used to compare the protocol performance to other existing link state routing protocols.
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Association of Children’s Urinary CC16 Levels with Arsenic Concentrations in Multiple Environmental MediaBeamer, Paloma, Klimecki, Walter, Loh, Miranda, Van Horne, Yoshira, Sugeng, Anastasia, Lothrop, Nathan, Billheimer, Dean, Guerra, Stefano, Lantz, Robert, Canales, Robert, Martinez, Fernando 23 May 2016 (has links)
Arsenic exposure has been associated with decreased club cell secretory protein (CC16) levels in adults. Further, both arsenic exposure and decreased levels of CC16 in childhood have been associated with decreased adult lung function. Our objective was to determine if urinary CC16 levels in children are associated with arsenic concentrations in environmental media collected from their homes. Yard soil, house dust, and tap water were taken from 34 homes. Urine and toenail samples were collected from 68 children. All concentrations were natural log-transformed prior to data analysis. There were associations between urinary CC16 and arsenic concentration in soil (b = -0.43, p = 0.001, R-2 = 0.08), water (b = -0.22, p = 0.07, R-2 = 0.03), house dust (b = -0.37, p = 0.07, R-2 = 0.04), and dust loading (b = -0.21, p = 0.04, R-2 = 0.04). In multiple analyses, only the concentration of arsenic in soil was associated with urinary CC16 levels (b = -0.42, p = 0.02, R-2 = 0.14 (full model)) after accounting for other factors. The association between urinary CC16 and soil arsenic may suggest that localized arsenic exposure in the lungs could damage the airway epithelium and predispose children for diminished lung function. Future work to assess this possible mechanism should examine potential associations between airborne arsenic exposures, CC16 levels, lung function, and other possible confounders in children in arsenic-impacted communities.
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Enfants victimes de l'insécurité routière : épidémiologie des traumatismes et séquellesJavouhey, E. 05 January 2007 (has links) (PDF)
Cette recherche avait pour objectif de mieux connaître l'épidémiologie des traumatismes par accident de la route chez l'enfant. Pour cela, des analyses ont été réalisées à partir des données d'une grande qualité : le Registre du Rhône. Les incidences de traumatismes routiers chez les enfants ont été calculées. La localisation et la nature des lésions ont été finement décrites, en fonction du type d'usager de la route. Le deuxième objectif était d'identifier des facteurs de risque de traumatisme sévère et de séquelles. Les handicaps secondaires aux traumatismes routiers ont été étudiés à partir d'une étude de cohorte prospective multicentrique conduite dans douze villes françaises, incluant 139 enfants sévèrement traumatisés de la route et admis en réanimation pédiatrique. Les déficiences fonctionnelles, comportementales et cognitives ainsi que les degrés d'incapacités et les retentissements sur la famille et la scolarité, ont été évalués six mois et un an après l'accident. Les différents outils d'évaluation ont montré leur complémentarité pour apprécier la réalité des handicaps. Des facteurs de risque de séquelles à un an ont été identifiés permettant de cibler les enfants qui devraient bénéficier d'une prise en charge et d'un suivi particuliers. Des recommandations pour la prévention ont pu être élaborées, concernant particulièrement l'utilisation des dispositifs de protection en voiture, à deux-roues, les modalités de prise en charge en fonction des facteurs de gravité et les modalités de traitement en phase aiguë.
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Etude géologique et géotechnique routière : la route nationale 75 entre Vif et le col de La Croix-Haute (Isère)Koseoglu, Mesut 19 March 1977 (has links) (PDF)
La route nationale 75 ( R . N. 75), surtout entre Vif et le Col de la Croix-Haute, manifeste plusieurs sortes de désordres affaissements, glissements de terrain, chutes de pierres, etc . ) qui posent de sérieux problèmes techniques en temps normal ou à l'occasion des travaux d'élargissement et de redressement et constituent aussi une gêne, voire un danger, pour les usagers . La concentration et la répétition de ces désordres justifiaient une étude géologique et géotechnique détaillée du tracé et de son voisinage, sujet du présent mémoire . Notre travail, à l'occasion duquel nous avons voulu montrer l'intérêt que présente, avant toute réalisation d'ouvrages de Génie civil, un examen géologique complet, comporte six chapitres : - le cadre géographique, où sont étudiés les caractères généraux de la région, sa morphologie, son climat et son urbanisation ; - le cadre géologique, consacré à l'étude lithologique et structurale des terrains quaternaires et du socle, ainsi qu'à leur hydrogéologie; - le troisième chapitre est réservé à l'étude géotechnique de chacune de ces formations, à partir d'essais de laboratoire et d'observations de terrain; - l'utilisation des méthodes géophysiques a été abordée dans le quatrième chapitre ; - dans le cinquième chapitre, nous avons passé en revue les diverses catégories de désordres actuellement recensées . L'étude de leur contexte géologique, hydrogéologique et géotechnique, ainsi que la consultation des dossiers de l'Equipement, qui nous ont permis d'obtenir des informations sur les observations déjà effectuées et sur le passé de ces désordres, nous ont aidé à en déterminer les causes et à proposer les solutions qui nous semblent le mieux s'y adapter; Enfin, à la lumière des données obtenues précédemment, qui permettent un jugement sur l'aptitude à l 'implantation routière dans les divers terrains, en fonction de leur nature et de la morphologie locale, nous avons établi une carte géotechnique, destinée à faciliter l'étude de futurs projets et le choix entre des variantes de leur tracé .
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Contribution à l'étude de sols latéritiques du Sénégal et du BrésilNdiaye, Massamba 09 September 2013 (has links) (PDF)
Cette étude porte sur les matériaux graveleux latéritiques utilisés dans de nombreux pays pour la construction des couches de fondation et de base des chaussées routières. Au Sénégal, les matériaux sont sélectionnés par référence aux règles du CEBTP de 1972, révisées en 1980. Les graveleux latéritiques doivent respecter des fuseaux granulométriques avant ou après compactage. Des conditions sont aussi imposées à l'indice CBR, à l'indice de plasticité et à l'optimum Proctor. Les recherches présentées dans ce rapport concernent différentes questions :- quel est l'effet du compactage à différentes énergies sur la fragmentation des particules solides et la modification de la courbe granulométrique ? Comment en tenir compte dans la sélection des matériaux et donc leur classification ? Comment se comportent ces matériaux dans les chaussées sous l'effet du compactage à la mise en œuvre puis de la circulation ?- peut-on trouver une corrélation entre l'indice CBR et les paramètres granulométriques ou géotechniques du sol ? Les corrélations sont-elles valables pour tous les sites ou seulement à l'échelle d'une carrière ?- comment réagit le sol graveleux latéritique lorsqu'on le mélange avec un autre matériau dépourvu de particules fines pour améliorer sa plasticité et sa résistance ?- comme une partie des recherches a eu lieu au Brésil, le rapport compare les procédures expérimentales utilisées au Brésil et au Sénégal. La pertinence de l'utilisation des coefficients de fragmentabilité et dégradabilité, introduits dans la classification des sols latéritiques de Rodrigues et al. pour caractériser l'évolution des graveleux latéritiques, a été évaluée par des essais de laboratoire sur le matériau de la carrière de Lam-Lam et le même matériau mis en œuvre en couche de base sur deux routes du Sénégal. Le coefficient de dégradabilité ne différencie pas les matériaux et le coefficient de fragmentabilité semble être un meilleur paramètre. L'étude de l'évolution des classes granulaires des latérites de deux carrières du Sénégal et deux carrières du Brésil sous compactage CBR confirme l'importance de la fragmentation des particules les plus grandes et le décalage des courbes granulométriques vers les sols plus fins, mais ces changements dépendent de la nature des latérites testées. Il en résulte que l'étude des matériaux graveleux latéritiques doit continuer de se faire à l'échelle de la carrière. La méthode de régression linéaire multiple a été appliquée à la prévision de l'indice CBR des matériaux prélevés dans deux carrières sénégalaises (40 prélèvements à Sindia et 46 à Dougar). Cette étude a montré que l'on peut trouver des approximations acceptables à l'échelle de chaque carrière pour calculer l'indice CBR à partir des courbes granulométriques et à partir de six paramètres choisis pour leur influence potentielle sur cet indice : le passant au tamis 80µm, les caractéristiques de courbure et d'étendue de la courbe granulométrique, l'indice de plasticité et les caractéristiques Proctor. Mais les formules établies sur un site sont inadaptées à la prévision de l'indice CBR sur d'autres sites, ce qui confirme que les analyses doivent se faire à l'échelle de la carrière. La lithostabilisation des latérites de Lam-Lam et de Sindiapar mélange avec 30% et 10% de sable de KeurMassar pour abaisser leur indice de plasticité naturel a eu l'effet attendu sur la plasticité, tout en respectant les critères granulométriques. Mais l'effet de l'ajout du sable sur l'indice CBR est inattendu et devra être étudié : diminution pour la latérite de Lam-Lam et augmentation pour la latérite de Sindia. La comparaison des normes françaises et brésiliennes a montré que, malgré de légères différences, les résultats sont globalement équivalents. La plus grande différence concerne l'indice CBR, qui est déterminé avec des énergies de compactage différentes et donne des résultats plus faibles au Brésil. Mais les conditions imposées aux matériaux sont adaptées à ces valeurs
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Optimal Path Queries in Very Large Spatial DatabasesZhang, Jie January 2005 (has links)
Researchers have been investigating the optimal route query problem for a long time. Optimal route queries are categorized as either unconstrained or constrained queries. Many main memory based algorithms have been developed to deal with the optimal route query problem. Among these, Dijkstra's shortest path algorithm is one of the most popular algorithms for the unconstrained route query problem. The constrained route query problem is more complicated than the unconstrained one, and some constrained route query problems such as the Traveling Salesman Problem and Hamiltonian Path Problem are NP-hard. There are many algorithms dealing with the constrained route query problem, but most of them only solve a specific case. In addition, all of them require that the entire graph resides in the main memory. Recently, due to the need of applications in very large graphs, such as the digital maps managed by Geographic Information Systems (GIS), several disk-based algorithms have been derived by using divide-and-conquer techniques to solve the shortest path problem in a very large graph. However, until now little research has been conducted on the disk-based constrained problem. <br /><br /> This thesis presents two algorithms: 1) a new disk-based shortest path algorithm (DiskSPNN), and 2) a new disk-based optimal path algorithm (DiskOP) that answers an optimal route query without passing a set of forbidden edges in a very large graph. Both algorithms fit within the same divide-and-conquer framework as the existing disk-based shortest path algorithms proposed by Ning Zhang and Heechul Lim. Several techniques, including query super graph, successor fragment and open boundary node pruning are proposed to improve the performance of the previous disk-based shortest path algorithms. Furthermore, these techniques are applied to the DiskOP algorithm with minor changes. The proposed DiskOP algorithm depends on the concept of collecting a set of boundary vertices and simultaneously relaxing their adjacent super edges. Even if the forbidden edges are distributed in all the fragments of a graph, the DiskOP algorithm requires little memory. Our experimental results indicate that the DiskSPNN algorithm performs better than the original ones with respect to the I/O cost as well as the running time, and the DiskOP algorithm successfully solves a specific constrained route query problem in a very large graph.
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A historic and cultural resources survey for Indiana State Road 26Nelson, Ross A. January 2007 (has links)
The following is a historic and cultural resources survey for the Indiana State Road 26 corridor between Lafayette and Fairmount, Indiana. The main goals of the survey are to examine the historic and cultural resources on State Road 26, and to provide information on its potential as a state byway.The historic and cultural resources survey is divided into four portions- a) a history of the State Road 26 corridor, b) descriptions of the corridor's historic and natural features, c) current issues facing the corridor, and d) ideas on how to market and interpret the corridor. The corridor has been separated into five distinct sections in the study. The study also includes visuals in the appendices to help illustrate the nature of the corridor. / Department of Architecture
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Evidence-based spatial intervention for regeneration of deteriorating urban areas : a case of study from Tehran, IranRismanchian, Omid January 2012 (has links)
Throughout the urban development process over the last seven decades in Tehran, the capital city of Iran, many self-generated neighbourhoods have developed in which the majority of the residents are low-income families. On one hand, the main spatial attribute of these deprived neighbourhoods is spatial isolation from the surrounding, more affluent areas, which is accompanied by inadequate urban infrastructure and a lack of accessibility and permeability. On the other hand, the Tehran City Revitalisation Organisation - the governmental sector which is in charge of the deprived areas - is incapable of conducting urban regenerations without investment from the private sector, and is seeking methods to create ‘socio-economic stimulant zones’ to attract private sector participation in regeneration programmes. In this regard, this research investigates the notion of ‘spatial isolation’ which in return causes socio-economic isolation as highlighted in the literature. The research suggests that in order to develop feasible regeneration programmes, which can meet the interest of both people and government, and release the deprived area from isolation both spatially and socio-economically, the regeneration plans should focus on public open space developments as ‘socio-economic stimulant zones’. With regard to this idea, the research highlights the street as a ‘social arena’ – not arteries or thoroughfares – as the type of public open space in which its development could not only release the deprived areas from spatial isolation, but could also direct more pedestrian movement to and through the deprived neighbourhoods, making more opportunities for the creation of socio-economic interactions. In this respect, the theory of ‘natural movement’ and theories and literature of ‘integrated public open spaces’ form the theoretical framework of the research to support this idea. For further investigation, two case studies, one as the deprived area and one as the control area, have been chosen, and the spatial pattern of the city and the two cases have been analysed in regard to the notion of ‘spatial isolation’ through Space Syntax using Depthmap software and GIS. Also, the correlation between the distribution pattern of commercial land uses and syntactic measures across the city of Tehran is investigated to identify the potential streets in which to create commercial opportunities. Afterwards, in order to study the street life and the variety of activities the streets can afford, a few locally integrated streets in the deprived case have been chosen. At this stage, nineteen behaviours have been observed and classified in five major classes including the necessary, social, optional, hazardous, and occasional activities, and the correlation with syntactic measures are studied. Moreover, the methods of developing a route filtering system and a transformability index for identifying the most suitable streets for the creation of a pedestrian friendly network are discussed, using an example of a deprived area, integrating it with the surrounding urban fabric to create the ‘socio-economic stimulant zones’. The results show that by identifying the underlying spatial pattern of the urban fabric, it is possible to release the deprived areas from its spatial isolation through developing a street network without causing urban fragmentation. This approach could also form a cost-effective basis for developing a pedestrian friendly street network as one of the ‘socio-economic stimulant zones’, which the Tehran City Revitalisation Organisation is looking for; the type of streets that not only support the necessary activities and transportation, but could also facilitate socio-economic interaction.
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INCORPORATING TRAVEL TIME RELIABILITY INTO TRANSPORTATION NETWORK MODELINGZhang, Xu 01 January 2017 (has links)
Travel time reliability is deemed as one of the most important factors affecting travelers’ route choice decisions. However, existing practices mostly consider average travel time only. This dissertation establishes a methodology framework to overcome such limitation.
Semi-standard deviation is first proposed as the measure of reliability to quantify the risk under uncertain conditions on the network. This measure only accounts for travel times that exceed certain pre-specified benchmark, which offers a better behavioral interpretation and theoretical foundation than some currently used measures such as standard deviation and the probability of on-time arrival.
Two path finding models are then developed by integrating both average travel time and semi-standard deviation. The single objective model tries to minimize the weighted sum of average travel time and semi-standard deviation, while the multi-objective model treats them as separate objectives and seeks to minimize them simultaneously. The multi-objective formulation is preferred to the single objective model, because it eliminates the need for prior knowledge of reliability ratios. It offers an additional benefit of providing multiple attractive paths for traveler’s further decision making.
The sampling based approach using archived travel time data is applied to derive the path semi-standard deviation. The approach provides a nice workaround to the problem that there is no exact solution to analytically derive the measure. Through this process, the correlation structure can be implicitly accounted for while simultaneously avoiding the complicated link travel time distribution fitting and convolution process.
Furthermore, the metaheuristic algorithm and stochastic dominance based approach are adapted to solve the proposed models. Both approaches address the issue where classical shortest path algorithms are not applicable due to non-additive semi-standard deviation. However, the stochastic dominance based approach is preferred because it is more computationally efficient and can always find the true optimal paths.
In addition to semi-standard deviation, on-time arrival probability and scheduling delay measures are also investigated. Although these three measures share similar mathematical structures, they exhibit different behaviors in response to large deviations from the pre-specified travel time benchmark. Theoretical connections between these measures and the first three stochastic dominance rules are also established. This enables us to incorporate on-time arrival probability and scheduling delay measures into the methodology framework as well.
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