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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.
51

Safety Assessment of Different Bike Infrastructure Types: A Data-Driven Approach / SAFETY ASSESSMENT OF DIFFERENT BIKE INFRASTRUCTURE TYPES

Imad Monzer, Yasmina January 2023 (has links)
This thesis comprises two studies that investigated bike infrastructure safety in North America. The first study conducted a corridor-level analysis to quantify the safety of different bike infrastructure types and assess the influence of corridor-specific characteristics on their performance. Using a Poisson-lognormal Full Bayesian model, the study analyzed fatal and injury bike-vehicle collisions on over 7800 corridors in Toronto, Canada. The findings revealed that bike infrastructure effectively reduces bike collisions, with cycle tracks demonstrating superior safety benefits due to the physical separation of cyclists from vehicular traffic. Cycle tracks were found to be particularly effective on long corridors with fewer intersections as bike-vehicle interactions along the corridor are minimized. Signed routes were safe on low-volume and low-speed roads, while bike lanes are more suited for a short section of high-volume corridors with a high intersection density. The second study assessed the safety of parking-protected bike lanes (PPBL), a new concept that is rapidly growing in North America. Utilizing data from nineteen street sections in Vancouver and Ottawa, the study developed a Full Bayesian Before-and-after model to evaluate the safety impacts of converting traditional painted bike lanes to PPBLs. The results indicated a significant reduction of 31.2% in total collisions after PPBL implementation. However, the effects of PPBLs on cyclist safety were found to be sensitive to factors such as bike path opening density, intersection density, and intersection treatments. In roads where proper intersection treatments and minimal protection of PPBL openings can be provided, painted bike lanes can be converted into PPBLs, and significant safety benefits can be expected. The findings of this thesis offer practical guidance for city planners and policymakers regarding the safety implications of different bike infrastructure types and the most appropriate conditions to implement them, which supports bike safety enhancement initiatives and attracts more people to bike. / Thesis / Master of Applied Science (MASc) / This thesis presents two studies that offer valuable insights to improve bike safety. The first study examined the safety of various bike infrastructure types along with the impact of corridor characteristics on their performance. The findings emphasized the effectiveness of cycle tracks in reducing collisions on long corridors with fewer intersections. Signed routes were found to be effective on low-volume and low-speed roads, while bike lanes were ideal on short sections of high-volume roads with a high intersection density. The second study assessed the impacts of new designed concept, known as the parking-protected bike lanes (PPBLs). The study showed that converting painted bike lanes to PPBLs significantly reduced total collisions. However, proper treatment of intersection and bikeway openings is crucial for enhancing cyclist safety and reducing multi-vehicle rear-end collisions. Where proper intersection treatment and minimal protection of bikeway openings can be provided, bike lanes can be safely converted into PPBLs.
52

Railway Mobility Hubs: A feature-based investment return analysis

Hidalgo González, Guillermo, Queirós, António January 2019 (has links)
While there has been considerable research regarding the role of Mobility Hubs in cities and transport networks, significant investment is required to develop these facilities. It is the correlation between investment, new users’ attraction and revenue generation that is the key for a sustainable development of Mobility Hubs and this investment must, therefore, be correctly assessed and targeted. This study aims to develop a methodology to determine the viability of investing in Mobility Hub features, weighing the investment on different Hub features and services against expected potential benefits and revenue generation, addressing the question: Can investment in Mobility Hub features be justified and, if so, which features maximize its expected positive impact? Based on a review of literature and definition of possible Hub features as variables, secondary research data was compiled to enable the analysis of expected impacts of each variable/feature in terms of new user’s attraction and revenue generation, which was then used to develop individual Net Present Value analysis of each feature. The result of these analysis demonstrates and concludes that different Hub features have the potential to generate substantially different investment outcomes, and that each feature should be analyzed individually prior to investment decision. It was also concluded by this research that the proposed assessment methodology can be used for future research on other listed Hub features, albeit with the constraint that primary data will be required when secondary research data is not available.
53

I strävan mot en grönare kommun : En kvalitativ fallstudie över Borås kommuns arbete med klimatväxling på sina enheter. / In pursuit of a greener municipality : A qualitative study on the municipality of Borås work with climate change on it’s units.

Rydholm Allard, Mattias, Insgård, Erik January 2017 (has links)
I detta examensarbete undersöks hur en svensk kommun kan arbeta med klimatväxling för att minska dess ekologiska fotavtryck och negativa effekt på miljön. Miljöfrågor är något som varje kommun brottas med dagligen för att föra arbetet kring hållbar utveckling framåt. Två forskningsfrågor formulerades som skulle ta reda på vilka faktorer som anställda i en svensk kommun upplever ökar miljömedvetenheten och användningen av elcykeln som arbetsfordon.  Tre olika hemtjänstenheter i Borås kommun har undersökts utifrån en kvalitativ ansats ihop med en litteraturstudie. Genom att fokusera på en infrastruktur som främjar elcykelanvändandet, erbjuda utbildningar kring elcykelanvändandet samt arbeta med kampanjer som ökar tillgängligheten på elcyklar kan kommuner skapa en kulturförändring vid val av fordon. Miljöutbildningar, miljöledningssystem och elcyklar ses som fungerande sätt att klimatväxla på, med olika preferenser från person till person beroende på tidigare kunskap och erfarenheter. De tre klimatväxlingsåtgärderna upplevs på olika sätt bidra till att personer agerar på ett mer hållbart sätt. Exempelvis genom bättre resurshantering, eco-driving och via byte av fordon släpps mindre CO2 ut per resa. / This thesis examines how a Swedish municipality can work with climate change to reduce its ecological footprint and negative effects on the environment. Environmental issues are something that every municipality encounters daily to forward the work on sustainable development. Two research questions were formulated that would determine the factors that employees in a Swedish municipality experience increases environmental awareness and usage of electrical bikes as work vehicles. Three different home care service units in Borås municipality has been examined based on a qualitative approach together with a literature study. By focusing on an infrastructure that encourage e-bike usage, provide education on ebikes and creating campaigns that increases the availability of e-bikes, municipalities can create a cultural change in the selection of vehicles. Environmental education, environmental management systems and e-bikes are working ways of climate compensation, with different preferences from person to person, depending on previous knowledge and experience. The three types of climate compensation alternatives are perceived as different ways to help people act more sustainable. For example, through better resource management, education in eco-driving and lesser CO2-emissions per trip by changing vehicle.
54

Bicyclist understanding, use, and preference of various innovative bicycle infrastructure treatments

Oliver, Jonathan Hunt 08 July 2011 (has links)
As bicycle transportation has increased, especially among commuters, so have the types of bicycle infrastructure facilities increased. This report focuses on the application of several of these innovative bicycle infrastructure treatments in three different scenarios: shared-lane facilities, bicycle-specific facilities, and high-conflict area treatments. The focus treatments include the sharrow, Sharrow Bicycle Priority Lane, Green Bicycle Priority Lane, Bicycles May Use Full Lane sign, green bike lane, bike-box, green lane in a conflict area, and elephant's footprint markings. The goal of this report is to gather how well bicyclists understand their meaning, how they would use each, and which treatments are most preferred among bicyclists. Data for this study was gathered in the form of an online survey administered to 1000 bicyclists of varying levels and purposes from different regions of the country. The survey gathers general rider characteristics, asks how each bicyclist would use each treatment in different traffic speed and volume scenarios, and finally each respondent rates each of the treatments in order of preference. Using the survey results, the effectiveness of each treatment is analyzed in detail by different population segments of those surveyed. Bicyclist riding characteristics and route choice factors are also examined in detail to better understand the sampled population of riders. The results are discussed and conclusions to the effectiveness of each treatment are made.
55

Uma abordagem heurística para um problema de rebalanceamento estático em sistemas de compartilhamento de bicicletas

Albuquerque, Fabio Cruz Barbosa de 20 May 2016 (has links)
Submitted by Fernando Souza (fernandoafsou@gmail.com) on 2017-08-15T11:46:12Z No. of bitstreams: 1 arquivototal.pdf: 884446 bytes, checksum: 92314027dddef8365b4a2e655b65bd78 (MD5) / Made available in DSpace on 2017-08-15T11:46:13Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 884446 bytes, checksum: 92314027dddef8365b4a2e655b65bd78 (MD5) Previous issue date: 2016-05-20 / The Static Bike Rebalancing Problem (SBRP) is a recent problem motivated by the task of repositioning bikes among stations in a self-service bike-sharing systems. This problem can be seen as a variant of the one-commodity pickup and delivery vehicle routing problem, where multiple visits are allowed to be performed at each station, i.e., the demand of a station is allowed to be split. Moreover, a vehicle may temporarily drop its load at a station, leaving it in excess or, alternatively, collect more bikes (even all of them) from a station, thus leaving it in default. Both cases require further visits in order to meet the actual demands of such station. This work deals with a particular case of the SBRP, in which only a single vehicle is available and the objective is to nd a least-cost route that meets the demand of all stations and does not violate the minimum (zero) and maximum (vehicle capacity) load limits along the tour. Therefore, the number of bikes to be collected or delivered at each station should be appropriately determined in order to respect such constraints. This is a NP-Hard problem since it contains other NP-Hard problems as special cases, hence, using exact methods to solve it is intractable for larger instances. Several methods have been proposed by other authors, providing optimal values for small to medium sized instances, however, no work has consistently solved instances with more than 60 stations. The proposed algorithm to solve the problem is an iterated local search (ILS) based heuristic combined with a randomized variable neighborhood descent (RVND) as local search procedure. The algorithm was tested on 980 benchmark instances from the literature and the results obtained are quite competitive when compared to other existing methods. Moreover, the method was capable of nding most of the known optimal solutions and also of improving the results on a number of open instances. / O Problema do Rebalanceamento Est atico de Bicicletas (Static Bike Rebalancing Problem, SBRP) e um recente problema motivado pela tarefa de reposicionar bicicletas entre esta c~oes em um sistema self-service de compartilhamento de bicicletas. Este problema pode ser visto como uma variante do problema de roteamento de ve culos com coleta e entrega de um unico tipo de produto, onde realizar m ultiplas visitas a cada esta c~ao e permitido, isto e, a demanda da esta c~ao pode ser fracionada. Al em disso, um ve culo pode descarregar sua carga temporariamente em uma esta c~ao, deixando-a em excesso, ou, de maneira an aloga, coletar mais bicicletas (at e mesmo todas elas) de uma esta c~ao, deixando-a em falta. Em ambos os casos s~ao necess arias visitas adicionais para satisfazer as demandas reais de cada esta c~ao. Este trabalho lida com um caso particular do SBRP, em que apenas um ve culo est a dispon vel e o objetivo e encontrar uma rota de custo m nimo que satisfa ca as demandas de todas as esta c~oes e n~ao viole os limites de carga m nimo (zero) e m aximo (capacidade do ve culo) durante a rota. Portanto, o n umero de bicicletas a serem coletadas ou entregues em cada esta c~ao deve ser determinado apropriadamente a respeitar tais restri c~oes. Trata-se de um problema NP-Dif cil uma vez que cont em outros problemas NP-Dif cil como casos particulares, logo, o uso de m etodos exatos para resolv^e-lo e intrat avel para inst^ancias maiores. Diversos m etodos foram propostos por outros autores, fornecendo valores otimos para inst^ancias pequenas e m edias, no entanto, nenhum trabalho resolveu de maneira consistente inst^ancias com mais de 60 esta c~oes. O algoritmo proposto para resolver o problema e baseado na metaheur stica Iterated Local Search (ILS) combinada com o procedimento de busca local variable neighborhood descent com ordena c~ao aleat oria (randomized variable neighborhood descent, RVND). O algoritmo foi testado em 980 inst^ancias de refer^encia na literatura e os resultados obtidos s~ao bastante competitivos quando comparados com outros m etodos existentes. Al em disso, o m etodo foi capaz de encontrar a maioria das solu c~oes otimas conhecidas e tamb em melhorar os resultados de inst^ancias abertas.
56

Att sadla om och styra mot hållbar mobilitet : Användares perspektiv på hållbarhetsinitiativet LinBike - Linköpings elcykelpool

Holmsten, Jonathan, Arnåsen, Joakim January 2020 (has links)
Linköpings kommun invigde hösten 2019 en elcykelpool kallad LinBike i syfte att bidra till stadens utveckling och nå klimatmålen. Denna studie syftar till att undersöka användarna av LinBike för att förstå varför den används och huruvida den kan bidra till fler hållbara resor. Genom kvalitativa gatuintervjuer med 24 användare har fem olika mobilitetstyper identifierats som sammanfattar användarnas förhållningssätt till systemet. Analys av resultatet visar att elcyklarna främst används tack vare tjänstens bekvämlighet och prisvärdhet. LinBike bidrar till att användarna i många fall kan genomföra sina vardagliga resor enklare än innan. Förbättringsåtgärder föreslås som anses nödvändiga för att tjänsten ska behålla användare och bidra till en mer hållbar mobilitet. Studiens slutsatser är bland annat att klimatsmarta mobilitetstjänster bör fokusera på att vara smidiga och lättillgängliga för att locka användare. LinBike som färdmedel ersätter idag främst andra hållbara transportmedel och därför kan det inte konstateras att tjänsten bidrar till en mer hållbar mobilitet. / Linköpings municipality has during the autumn of 2019 established an electric bike-sharing system called LinBike with the purpose to contribute to the city’s development and reach its climate goals. The scope of this thesis is to study the users of LinBike to understand why it is used and whether it contributes to a sustainable mobility or not. Through qualitative street interviews with 24 users, five types of mobility users have been identified which summarize the users attitude towards the system. Analysis of the results demonstrate that the E-bikes are used mainly because of the convenience and the price of the service. LinBike helps make everyday travel easier than before. Improvement measures are proposed which are considered necessary for the service to maintain users and contribute to a more sustainable mobility. Conclusions are that climate-smart mobility services should focus on being comfortable and accessible to attract users. LinBike users usually replace other sustainable modes of transportation and thus it cannot be concluded that the service contributes to a more sustainable mobility.
57

Untersuchung und Implementierung von Vorhersage- und Optimierungsmethoden für die Reichweite von Elektromobilen am Beispiel des E-Bikes

Windisch, Katrin 15 September 2011 (has links)
Durch steigende Rohölpreise werden alternative Antriebsmöglichkeiten zu Verbrennungsmotoren gesucht, ein aussichtsreiches Konzept ist die Elektromobilität. Elektromotoren werden nicht nur bei Automobilen eingesetzt sondern auch bei Fahrrädern, zum Beispiel bei Pedelecs. In der vorliegenden Arbeit werden verschiedene Möglichkeiten für die Optimierung der Reichweite dieser Fahrräder untersucht. Dafür wird zuerst ein vereinfachtes Modell für ein Pedelec hergeleitet, mit dem die benötigte Energiemenge für eine vorgegebene Strecke errechnet wird. Auf Grundlage dieser Berechnung werden im zweiten Teil verschiedene Optimierungsmethoden untersucht. Anschließend wird die Implementierung einer Optimierungsmethode vorgestellt. Zum Abschluss erfolgt eine Diskussion der Ergebnisse, eine kurze Zusammenfassung und ein Ausblick auf zukünftige Aufgaben.:Abbildungsverzeichnis iii Tabellenverzeichnis iv Codeverzeichniss v Bibliographische Angaben vi 1. Einleitung 1 1.1. Motivation 1 1.2. Diskussion der Aufgabenstellung 1 1.3. Gliederung 2 2. Modellierungsbetrachtung 3 2.1. Arten von Elektrofahrrädern 3 2.2. Modellierung von Elektrofahrzeugen 3 2.3. Spezielles Modell am Beispiel des Pedelecs 5 2.3.1. Beschreibung des Test-Pedelecs 5 2.3.2. Modifizierung des allgemeinen Modells 6 2.3.3. Zusammensetzung der physikalischen Leistung 7 3. Routendatenaufbereitung 11 3.1. Dateiformat 11 3.2. Kartentools 12 3.2.1. Routenplanung 12 3.2.2. Auswertung gefahrener Routen 12 3.3. Umrechnung von geographischer Breite und Länge 13 3.4. überarbeitung der Höhendaten 15 4. Optimierung der Fahrerunterstützung 17 4.1. Vorbetrachtungen 17 4.2. GewählteOptimierungsmethode 21 4.2.1. Sortierte Rückwärtsmethode 22 4.2.2. Binäre Suche 24 5. Implementierung in Python 27 5.1. Vorbereitung der Daten 27 5.2. Berechnung der Leistung 27 5.3. Optimierung 28 5.4. Auswertung 28 6. Diskussion der Ergebnisse 29 6.1. Diskussion und Ansätze für Weiterentwicklungen 29 6.2. Zusammenfassung 30 6.3. Ausblick 31 Literaturverzeichnis 33 A. Quellcode 36 A.1. Modul optimizetrack 39 A.1.1. Optionen für den Aufruf 39 A.2. Modul optimize 39 A.2.1. Klasse Optimizer 39 A.3. Modul simplegpx 42 A.3.1. Klasse SimpleGPXPoint 42 A.4. Module trackwrapper 43 A.4.1. Globale Konstanten 43 A.4.2. Klasse TrackSegment 43 A.4.3. Klasse TrackData 44 B. Verzeichnisstruktur der Begleit-CD 54
58

The recyclists : bikes, borders and basura

Melanson, Michael P., 1978- 05 August 2010 (has links)
In January, 2009, I joined Bikes Across Borders, a local grassroots organization, on their yearly bike caravan to Mexico. The group works to promote bicycles, both here and in Mexico, as an environmentally and financially sound alternative to motorized transportation. Each winter, members ride bicycles they build out of salvaged parts to border cities in Mexico. They give these bicycles to maquiladora workers who would otherwise spend a large portion of their income on transportation. These workers make a fraction of what they would in the U.S. and live in shacks amid the pollution from the factories they work in. This is the story of one group’s attempt at making a difference in the lives of these workers. / text
59

Cycling in the Crescent City: An exploration of the spatial variation in bicycle commuting in New Orleans

Bahr, Emilie S 17 May 2013 (has links)
This thesis examines the spatial variation in bicycle commuting across New Orleans. It identifies where in the city bicycle commuting is most and least prevalent. It also explores factors that are promoting and discouraging utilitarian bicycling. A review of existing literature on variables found to influence transportation bicycling is conducted, and a survey is disseminated to residents across the city to determine some of the motivations for and obstacles to transportation bicycling locally. Additionally, case studies are compiled pertaining to two neighborhoods falling on opposite ends of the bike-commute spectrum. These include analysis of socio-economic and demographic data; an evaluation of the built environment using maps and field observation; and interviews to assess residents’ attitudes about and experiences with transportation bicycling. In the end, this thesis should be helpful in pinpointing variables influencing bicycle commute rates and in determining the types of policies and investments that may be most effective in encouraging more bicycling in New Orleans and across the country.
60

Measuring the Sustainability of U.S. Public Bicycle Systems

Williamson, Max W 15 December 2012 (has links)
As cities worldwide plan for increasing urbanization levels, new challenges in mobility will arise. Any approach taken to address these new issues will need to consider how to move more people with declining resources, thus the need for a sustainable solution arises. This thesis examines the growing trend of cities creating public bicycle systems as a means to add sustainability to a transportation system and identifies what are the criteria and indicators of a sustainable public bicycle. The criteria and indicators are used to examine data collection techniques of three Public Bicycle Systems in the United States: Capital Bikeshare in Washington, D.C., Nice Ride in Minneapolis, Minnesota and Denver B-Cycle in Denver, Colorado.

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