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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Návrh řešení cestní sítě pro komplexní pozemkovou úpravu. / The proposal of a road network plan in a complex land consolidation project

ZÍDKOVÁ, Eva January 2008 (has links)
The diploma work is concerned on evaluation of the existing road network in complex land consolidation Plav. The aim of this work was to design reconstructions of existing roads and construction of new field roads and evaluate necessary appropriation of land. Further aim is to design a plan of additional arrangements {--} outplanting of attendant growth, drains e.g. and evaluate the role of road network in soil protection from erosion. The cadastral ground Plav has 510 hectares and is situated approximately 8 km far from České Budějovice. Field survey focused on road network as an integral part and basis for evaluation of real state of analysed area. The road network in analysed area is insuffiecient. Low density of road network, unsatisfactory technical state, neglected or missing attendant growth demand a lot of arrangements. Many reconstructions and constructions of new roads were planed.
22

HORN - Hank and OpenDRIVE Road Networks : An editor for creating HANK scenarios while working with OpenDRIVE

Öberg, Kim January 2012 (has links)
HORN is a solution to the problem of how to implement scenarios in a more efficient way than was previously possible allowing researchers who wish to create scenarios for HANK the ability to quicker implement larger scenarios than was previously possible. OpenDRIVE is an open standard for road networks that is believed to be the way forward and Horn is an attempt at unifying OpenDRIVE scenarios with HANK - the driving simulator currently in use at Link\"{o}pings Universitet, thus futureproofing all work done to implement scenarios. Before HORN HANK scenarios were laboriously constructed with a really bad program or by hand and HORN tries to make the process far less painful. This thesis describes how to work with the Road Network Editor program HORN ("Hank and OpenDRIVE Road Networks") that was developed for working with HANK's scenarios as well as my experience implementing it and some of the fascinating rules for how to draw some exotic two dimensional geometries I found out about as I worked on HORN.
23

Vehicle Routing Problems with road-network information / Problèmes de tournées de véhicules avec des informations du réseau routier

Ben Ticha, Hamza 20 November 2017 (has links)
Les problèmes de tournées de véhicules (VRPs) ont fait l’objet de plusieurs travaux de recherche depuis maintenant plus de 50 ans. La plupart des approches trouvées dans la littérature s’appuient sur un graphe complet ou un nœud est introduit pour tout point d’intérêt du réseau routier (typiquement les clients et le dépôt). Cette modélisation est, implicitement, basée sur l’hypothèse que le meilleur chemin entre toute paire de points du réseau routier est bien défini. Cependant, cette hypothèse n’est pas toujours valide dans de nombreuses situations. Souvent, plus d’informations sont nécessaires pour modéliser et résoudre correctement le problème. Nous commençons par examiner ces situations et définir les limites de la modélisation basée sur un graphe complet. Nous proposons un état de l’art des travaux qui examinent ces limites et qui traitent des VRPs en considérant plus d’informations issues du réseau routier. Nous décrivons les approches alternatives proposées, à savoir la modélisation utilisant un multi-graphe et celle utilisant la résolution directe sur un graph représentant le réseau routier. Dans une seconde étude, nous nous intéressons à l’approche basée sur la construction d’un multi-graphe. Nous proposons, d’abord, un algorithme qui permet de calculer d’une manière efficace la représentation par multi-graph du réseau routier. Puis, nous présentons une analyse empirique sur l’impact de cette modélisation sur la qualité de la solution. Pour ce faire, nous considérons le problème classique VRPTW comme un problème de pilote. Par la suite, nous développons une méthode heuristique efficace afin de résoudre le VRPTW basée sur une représentation par un multi-graphe.Dans une troisième étape, nous nous concentrons sur l’approche basée sur la résolution directe du problème sur un graphe représentant le réseau routier. Nous développons un algorithme de type branch-and-price pour la résolution de cette variante du problème. Une étude expérimentale est, ensuite, menée afin d’évaluer l’efficacité relative des deux approches. Enfin, nous étudions les problèmes de tournées de véhicules dans lesquels les temps de parcours varient au cours de la journée. Nous proposons un algorithme de type branch-and-price afin de résoudre le problème avec des fenêtres de temps directement sur le graphe représentant le réseau routier. Une analyse empirique sur l’impact de l’approche proposée sur la qualité de la solution est proposée. / Vehicle routing problems (VRPs) have drawn many researchers’ attention for more than fifty years. Most approaches found in the literature are, implicitly, based on the key assumption that the best path between each two points of interest in the road network (customers, depot, etc.) can be easily defined. Thus, the problem is tackled using the so-called customer-based graph, a complete graph representation of the road network. In many situations, such a graph may fail to accurately represent the original road network and more information are needed to address correctly the routing problem.We first examine these situations and point out the limits of the traditional customer-based graph. We propose a survey on works investigating vehicle routing problems by considering more information from the road network. We outline the proposed alternative approaches, namely the multigraph representation and the road network approach.Then, we are interested in the multigraph approach. We propose an algorithm that efficiently compute the multigraph representation for large sized road networks. We present an empirical analysis on the impact of the multigraph representation on the solution quality for the VPR with time windows (VRPTW) when several attributes are defined on road segments. Then, we develop an efficient heuristic method for the multigraph-based VRPTW.Next, we investigate the road network approach. We develop a complete branch-and-price algorithm that can solve the VRPTW directly on the original road network. We evaluate the relative efficiency of the two approaches through an extensive computational study.Finally, we are interested in problems where travel times vary over the time of the day, called time dependent vehicle routing problems (TDVRPs). We develop a branch-and-price algorithm that solves the TDVRP with time windows directly on the road network and we analyze the impact of the proposed approach on the solution quality.
24

Generalizace cestní sítě v topografických mapách / Generalization of Road Network in Topographic Maps

Vojtíšková, Zuzana January 2017 (has links)
Generalization of Road Network in Topographic Map Abstract The diploma thesis presents automated selection of the elements of path network. The review deals with this term and describes its position in map generalization process; the ways of path thinning apllied in the main Czech cartography institutions are reviewed too. Next part of the thesis describes the data and the tools that are applied in the proposed method. The main part introduces the suggested method of selecting elements of path network which was implemented on the test data. Keywords: map generalization, path network, path thinning, graph theory, ZABAGED, ArcGIS, Python, NetworkX
25

Automatic road network extraction from high resolution satellite imagery using spectral classification methods

Hauptfleisch, Andries Carl 30 July 2010 (has links)
Road networks play an important role in a number of geospatial applications, such as cartographic, infrastructure planning and traffic routing software. Automatic and semi-automatic road network extraction techniques have significantly increased the extraction rate of road networks. Automated processes still yield some erroneous and incomplete results and costly human intervention is still required to evaluate results and correct errors. With the aim of improving the accuracy of road extraction systems, three objectives are defined in this thesis: Firstly, the study seeks to develop a flexible semi-automated road extraction system, capable of extracting roads from QuickBird satellite imagery. The second objective is to integrate a variety of algorithms within the road network extraction system. The benefits of using each of these algorithms within the proposed road extraction system, is illustrated. Finally, a fully automated system is proposed by incorporating a number of the algorithms investigated throughout the thesis. Copyright / Dissertation (MSc)--University of Pretoria, 2010. / Computer Science / unrestricted
26

Strojové zpracování časoprostorových dat pro potřeby územního plánování. / Machine processing of space-time data for spatial planning.

Brožek, Jan January 2020 (has links)
The diploma thesis deals with the processing of raw data from vehicle tracking by means of GPS in order to obtain traffic quantities as a possible source of data for traffic surveys and subsequent analysis in the field of traffic modeling.
27

Modeling and simulation of operational forest planning in relation to road network layout, cable corridor layout and timber transportation / 路網配置, 架線配置, 原木輸送に関連する森林作業計画のモデル化とシミュレーション

Shirasawa, Hiroaki 24 March 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第18321号 / 農博第2046号 / 新制||農||1021(附属図書館) / 学位論文||H26||N4828(農学部図書室) / 31179 / 京都大学大学院農学研究科森林科学専攻 / (主査)教授 吉岡 崇仁, 教授 德地 直子, 准教授 長谷川 尚史 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM
28

A comparative study of nature-inspired metaheuristic algorithms on sustainable road network planning

Luqman, Mohammed January 2022 (has links)
Global warming is a serious threat to the existence of human life on earth. Greenhouse gas emission is the major cause of global warming. Carbon dioxide is the major greenhouse gas emitted due to human activity. Road transport accounts for 15% of CO2 emissions worldwide. There are many initiatives adopted worldwide to minimize the emission of CO2 due to road transportation. Vehicle engines are upgraded to make it environment friendly, electric vehicles are promoted, public transport is promoted, etc. Apart from these, proper road network planning could also reduce emissions. It is not practical to completely replace the road transport system due to its importance in the transport of passengers and goods. This thesis is focused on finding ideal road conditions, that produce minimum CO2 emissions. The road network parameters that are studied in this thesis are speed limit, the number of vehicle lanes, and junction design. Due to time constraints, it is not feasible to do this study on a real road network. Hence, a simple artificial road network is created using a traffic simulator named SUMO for analysis. Both traffic congestion and the higher speed of the vehicles cause higher emissions. Roads are heavily interconnected in cities and road parameters of the adjacent roads should be adjusted together with the road being studied, to have an impact on the overall traffic. As adjacent road networks are too many numbers in cities, it is not feasible to validate every possible option. There is no algorithm invented so far to analyze such problems having too many possible states. However, there are optimization algorithms that can determine approximate solutions for such problems. In this thesis, I compared the performance of five nature-inspired metaheuristic algorithms on the sustainable road network problem. The five algorithms studied in this study are Particle Swarm Optimization, Genetic Algorithm, Artificial Bee Colony, Differential Evolution, and Harmony Search. The differential evolution algorithm generated the best result and was able to reduce the emissions by 6% and it is followed by genetic algorithms. Statistical tests are performed to evaluate whether the differences are significant or not.
29

Road Networks, Social Disorganization And Lethality, An Exploration Of Theory And An Examination Of Covariates

Poole, Aaron 01 January 2013 (has links)
Utilizing a Criminal Event Perspective, the analyses of this dissertation test a variety of relationships to the dependent variable: the Criminal Lethality Index. Data from the National Incident-Based Reporting System, the Census and American Community Survey, the American Trauma Society, and data derived from the Census’s mapping TIGER files are combined to create a database of 190 cities. This database is used to test road network connectivity (Gama Index), medical resources, criminal covariates and Social Disorganization variables in relation to a city’s Criminal Lethality Index. OLS regression demonstrates a significant and negative relationship between a city’s Gama Index and its Criminal Lethality Index. In addition, percent male, percent black, median income and percent of the population employed in diagnosing and treating medical professions were all consistently positively related to Criminal Lethality. The percent of males 16 to 24, percent of single parent households, and Concentrated Disadvantage Index were all consistently and negatively related to Criminal Lethality. Given these surprising results, additional diagnostic regressions are run using more traditional dependent variables such as the number of murders in a city and the proportion of aggravated assaults with major injuries per 100,000 population. These reveal the idiosyncratic nature of utilizing the Criminal Lethality Index. This dependent variable has proven useful in some circumstances and counterintuitive in others. The source of the seemingly unintuitive results is the fact that certain factors only reduce murders but many factors impact both murder and aggravated assaults, thereby creating difficultly when trying to predict patterns in Criminal Lethality
30

Möjligheter för automatiserade godstransporter I Västerbotten : Vilken påverkan har väginfrastruktur för potentialen till automatiserade transportsystem i region Västerbotten?

Törnell, Axel January 2021 (has links)
The technology behind self-driving trucks in currently under development for deployment on public road. The objective of this study is to explore and understand the number of industries that could be reached by self-driving trucks with the limits of Västerbottens current road network.  The effect from implementing self-driving trucks is an emerging research field. We do not understand to what extent the physical infrastructure affect which industries may be able to use self-driving trucks since there is a lack of exploration and research within the scientific literature.  The thesis has been conducted by a literature study, interviews, and a spatial analysis. The spatial analysis examined the potential for self-driving trucks to access industries depending on what road infrastructure self-driving trucks are assumed to be able to operate. The number of industries that self-driving trucks can access was calculated for four different subsets of the road networks: The European highway network, National highway network, Functional priority road network and roads with driving lane with over 5m. This resulted in the conclusion that the European highway network had the lowest number of industries within the search radiuses, a considerate amount of all industries (49%) was still within a 1 km radius. The road type “Driving lane with over 5m” having a clear majority of the industries with a total of 94% of the industries within a 1 km radius.  The findings of this study suggest that self-driving trucks which are capable of operating only at a limited part of the road network still potentially could be used for a relatively large number of industrial freight transport flows in Västerbotten. This could indicate that self-driving trucks with a limited operating design domain could address a substantial share of the freight transport market.

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