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Development of Truck Route Choice Data Using Truck GPSKamali, Mohammadreza 06 November 2015 (has links)
Over the past few decades, the value and weight of freight shipments have grown steadily in both developed and developing countries. A recent statistic in the U.S. reveals that weight of shipments increased from 18,879 to 19,662 million tons between 2007 and 2012 (1). It is also expected that this amount will increase to 28,520 million tons by 2040 (1). It is worth mentioning that 67 percent of shipments are shipped by truck mode in 2012. The monetary value of freight is expected to escalate even faster than weight. This value is estimated to rise from US$ 882 per ton in 2007 to US$ 1,377 per ton in 2040. As a result, freight transportation management and modeling has aroused the interest of both public sector and groups of firms to improve the efficiency of the business operations. Traffic assignment plays a central role in the current freight modeling, and freight route analysis is of fundamental importance in understanding the truck flows explicitly.
In the first part of this thesis, large streams of truck-GPS data from the American Transportation Research Institute (ATRI) are cleaned, processed, and analyzed using easy to implement and practical procedures to study the diversity of observed truck routes between a given origin-destination (OD) pair. This is because, for any given OD pair, the analyst could observe and compare the route choices of a large number of trips, as opposed to observing only one or a few trips. Doing so helps in quantifying the number of different routes taken by trucks between an OD pair and paves the way for a systematic analysis of the “diversity” in route choices between any OD pair. This thesis develops methods to measure the diversity of routes between a given OD pair and identifies unique routes used between the given OD pair. From a practical standpoint, such analysis of the diversity in observed route choices helps in improving the existing route choice set generation algorithms.
In the second part of the thesis, the methodologies developed in the first part are implemented in an FDOT sponsored project entitled “GPS Data for Truck-Route Choice Analysis of Port Everglades Petroleum Commodity Flows”. This project aims to use truck-GPS data from ATRI to derive petroleum tanker trucks’ travel path (or route) information, describing the routes that the tanker trucks take to travel from Port Everglades to their final delivery points.
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Comprehensive Exploratory Analysis of Truck Route Choice Diversity in FloridaLuong, Trang D. 02 November 2017 (has links)
This thesis presents a comprehensive exploratory analysis of truck route choice diversity in the state of Florida, for both long-haul and short-haul truck travel segments. We employ six metrics to measure three different dimensions of diversity in truck route choice between any given origin-destination (OD) pair. These dimensions are: (1) number of distinct routes used to travel between the OD pair, (2) the extent of overlap (or lack thereof) among the routes, and (3) the evenness (or the dominance) of the usage of different unique routes. The diversity metrics were utilized to examine truck route choice diversity from over 73,000 truck trips that were derived from over 200 million GPS records of a large truck fleet. Descriptive analysis and statistical modeling of the diversity metrics offered insights on the determinants of various dimensions of truck route choice diversity between an OD pair. The results could be used to improve choice set generation algorithms for truck route choice modeling as well as in planning truck route policies and investments.
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Étude de l'influence du débit et de la température de l'eau sur le régime thermique autour des ponceaux construits sur pergélisolPerier, Loriane 23 April 2018 (has links)
L’apport de chaleur induit par les constructions routières est susceptible d’affecter le régime thermique du pergélisol sous-jacent et de causer des dommages importants. Sur l’Alaska Highway au Yukon (Canada), des problèmes d’instabilités sont fréquemment observés et certains sont localisés aux abords des ponceaux. En autorisant la libre circulation de l’air et de l’eau à travers une conduite, des perturbations thermiques additionnelles sont infligées au sol environnant. De plus, une mauvaise gestion du drainage de l’eau aux abords des ouvrages aggrave la sévérité des instabilités. Afin de documenter ces perturbations, deux ponceaux ont été instrumentés sur l’Alaska Highway au Yukon. Le premier est situé au site expérimental de Beaver Creek; le deuxième est proche de la frontière avec l’Alaska. Les températures du sol autour des ponceaux et la température de l’air dans les ponceaux ont été enregistrées pendant une année; tandis que la température de l’eau et le débit ont été enregistrés pendant deux printemps et étés. La collecte de ces données a permis de concevoir un modèle 2D sur le logiciel TEMP/W représentant le remblai et le ponceau de Beaver Creek. En parallèle, les données ont servi à valider un modèle mathématique établi basé sur des principes physiques. Ce modèle permet de calculer le flux de chaleur transmis au sol en fonction du débit et de la température de l’eau. Par la suite, des simulations de variation de débit et de température de l’eau ont été appliquées dans le modèle mathématique. Les différents flux de chaleur correspondants ont été appliqués sur le modèle thermique 2D afin de déterminer l’influence du débit et de la température de l’eau sur les températures du sol sous le ponceau. Des simulations similaires ont été conduites en faisant varier des paramètres de conception comme la présence ou non de l’isolant. Ce mémoire présente donc trois objectifs principaux; 1) l’amélioration des connaissances relatives à l’effet de la circulation de l’eau à travers un ponceau sur le régime thermique du sol sous-jacent; 2) la documentation sur le régime thermique autour de ponceaux routiers; et 3) l’étude de l’influence du débit et de la température de l’eau sur la stabilité thermique du sol. Finalement, une méthode de conception de système de drainage, permettant de limiter l’impact d’un ponceau sur la profondeur de dégel du sol sous-jacent, est présentée dans le présent mémoire. / Heat sources induced by road construction are likely to affect the thermal regime of underlying permafrost and cause significant damage. On the Alaska Highway in Yukon (Canada), instability problems have been observed and some are located close to culverts. Culverts allow free water and air circulation through the buried pipe. Thus, additional thermal disturbances occur at that location. In addition, poor water management around the embankment exacerbates instabilities. To document these disturbances, two culverts were monitored; one is located at the Beaver Creek test site and the second is close to the U.S Border. Air temperature within and soil temperatures around the culverts were recorded for one year, while water temperature and flow rate were recorded during two thawing seasons. The data collection allowed the design of a 2D model in TEMP/W representing thermal conditions around the Beaver Creek culvert. Then, these data were used to validate an established mathematical model based on the physical principles of heat transfer. The mathematical model calculates the heat flux transmitted to the ground as a function of water temperature and flow rate. Subsequently, variations of flow rate and water temperature were applied to the mathematical model. The corresponding heat fluxes were applied to the 2D thermal model in TEMP/W to determine the influence of flow rate and water temperature on soil temperatures below the culvert. Similar simulations were conducted with design parameters, such as the presence or absence of the insulation. This thesis 1) enhanced knowledge of the effects of flow rate and water temperature through a culvert on the soil thermal regime; 2) documented the thermal regime around culverts; and 3) studied the influence of flow rate and water temperature on the thermal regime. Finally, a drainage system design method is presented which aims to minimize the impact of a culvert on the thaw depth.
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An integrated control system for an Automatic Guided Vehicle (AGV)Boje, E.P., Kotze, B.J. January 2008 (has links)
Published Article / An immense amount of research is currently, being done on the development and use of Automatic Guided Vehicles (AGVs) in industry. An important component of this research often involves navigation and route-optimization of such AGVs. In this paper the design and control of an AGV, using a stationary control system and a GPS-like navigational system, is discussed. Substantial provision has also been made for the display of operational characteristics of the AGV on the stationary control unit.
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Développement d'un simulateur reproduisant le profil des routes sous les roues d'un véloBrassard, Francis January 2010 (has links)
L'industrie du vélo utilise à profusion le terme confort sans savoir parfaitement ce que cela représente. Aucun outil scientifique n'existe afin d'identifier le confort et ainsi la conception d'un simulateur de vibration de la route est envisagée. Le principal objectif de ce projet de maîtrise est de concevoir un simulateur permettant de reproduire le profil de la route afin de retrouver les mêmes niveaux de vibration que lorsque le vélo roule sur la route. Ainsi, la conception du simulateur se divise en deux parties : la conception mécanique du banc de test qui sert de pièce maîtresse du simulateur ainsi que le calcul des profils numériques des routes. Le premier volet présente la conception mécanique du banc de test. Le banc de test est la pièce maîtresse qui supporte le vélo et qui transmet le mouvement provenant des actionneurs à l'aide d'un bras d'amplification mécanique des mouvements. Le mouvement est créé par des actionneurs de la compagnie D-Box qui présentent plusieurs limitations et contraintes influençant directement la conception du banc de test et le calcul des profils de route. La démarche afin de calculer des profils numériques des routes est présentée dans le deuxième volet. Les profils de route sont la représentation numérique de la route réelle. Ces derniers servent de signal alimentant les actionneurs du banc de test. Afin de calculer les profils, il est nécessaire de faire des mesures d'accélération sur la route et, à l'aide de la technique du problème inverse, les profils de route sont calculés. La démarche de conception se termine avec une validation du simulateur. Ce chapitre dédié à la validation démontre que l'utilisation d'une amplification mécanique à l'aide d'un bras de levier n'influence pas les mesures. La précision de la reproduction de la route est également étudiée alors qu'un écart de 6% à 9% est remarqué entre les mesures d'accélération sur la route et celles sur le banc de test. Le dernier volet du mémoire présente un exemple d'utilisation possible du banc de test. Une étude comparative identifie qu'il n'est pas suggéré d'utiliser des masses inertes afin de remplacer un cycliste. Ces résultats sont basés sur des études dynamiques d'un cadre de vélo.
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Talk the walk : Empirical studies and data-driven methods for geographical natural language applicationsGötze, Jana January 2016 (has links)
Finding the way in known and unknown city environments is a task that all pedestrians carry out regularly. Current technology allows the use of smart devices as aids that can give automatic verbal route directions on the basis of the pedestrian's current position. Many such systems only give route directions, but are unable to interact with the user to answer clarifications or understand other verbal input. Furthermore, they rely mainly on conveying the quantitative information that can be derived directly from geographic map representations: 'In 300 meters, turn into High Street'. However, humans are reasoning about space predominantly in a qualitative manner, and it is less cognitively demanding for them to understand route directions that express such qualitative information, such as 'At the church, turn left' or 'You will see a café'. This thesis addresses three challenges that an interactive wayfinding system faces in the context of natural language generation and understanding: in a given situation, it must decide on whether it is appropriate to give an instruction based on a relative direction, it must be able to select salient landmarks, and it must be able to resolve the user's references to objects. In order to address these challenges, this thesis takes a data-driven approach: data was collected in a large-scale city environment to derive decision-making models from pedestrians' behavior. As a representation for the geographical environment, all studies use the crowd-sourced Openstreetmap database. The thesis presents methodologies on how the geographical and language data can be utilized to derive models that can be incorporated into an automatic route direction system. / <p>QC 20160516</p>
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Changing patterns of heroin use : examination of populations and individualsStrang, John Stanley January 1995 (has links)
No description available.
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The development and role of accident predictive modelsChatterjee, Kiron January 1995 (has links)
No description available.
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Samordning av transporter inom Uppsala Kommun och LandstingBerg, Martin January 2016 (has links)
The municipality and county administrations of Uppsala are planning a project for coordination of transports to their institutions and services across Uppsala County, which are today done separately. This report aims to analyze what the profits of such coordination might be, in terms of environmental care, economic and social aspects, given the resources available today. This is done by creating optimization models for both separate and coordinated transports, based on previously completed order tables, and comparing the results. The final results show at best a 13% improvement in driving distance and a 7% improvement in driver work time, which transfers into 172 000 SEK savings yearly and significant reductions in CO2-emissions while easing workload during high intensity days. Changes in the transport fleet might increase this to up to 272 000 SEK while possibly further reducing emissions but without creating significant increase in workload for drivers.
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Route Descriptions Using Maps, Photomaps, and Imagery: An Experimental AnalysisKelley, Maureen 11 July 2013 (has links)
Previous route description experiments conducted by psychologists
show there are differences between males and females in the use of landmarks when describing routes. Previous research has shown that females used landmarks and egocentric forms of turn descriptors more often than males for route descriptions. This method is known as route knowledge in the spatial knowledge literature. Males, conversely, were seen to use fewer landmarks and more cardinal direction descriptions and standard distances when describing routes. Spatial knowledge literature terms this method survey knowledge. The current experiment tested the hypothesis that sex is not the determinant of landmark usage for route descriptions but different cartographic methods depicting the same locale determine whether landmarks are described. Two
quasi-experiments were conducted using different map types. Results of
the experiments show that map type, not sex, influences landmark usage
for route descriptions. / 10000-01-01
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