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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.
61

Utveckling av ett cykelskåp anpassat för stadsmiljö / Development of a bike box matching city environments

Öberg, Daniel January 2019 (has links)
Projektet började som en öppen fråga i samarbete med ett konsultföretag inom produktutveckling att utveckla en säkrare parkering för cyklar. Det utfördes därför en omfattande förstudie för att utvärdera cykelvärlden och se potentiella utvecklingsmöjligheter hos olika typer av cykelparkeringar. Blidsberg mekaniska är ett företag som tillverkar cykelparkeringar och andra sorts produkter för utemiljöer. De involverades i arbetet och ville utöka sitt sortiment med ett nytt cykelskåp. Designprocessen började med en bred marknadsundersökning för att analysera befintliga cykelparkeringar i en förstudie. Under förstudien samlades även behov in som sedan skapade en kravspecifikation. Det kreativa arbetet i att utveckla ett nytt cykelskåp tog hjälp av olika kreativitetsmetoder som genererade flertalet koncept som sedan jämfördes i en matris. Ett vinnande koncept framställdes och kunde konkurrera med en redan befintlig lösning. Resultatet blev en kombination av redan befintliga lösningar. Cykelskåpet tar inte upp mer plats än behövligt för att de flesta cyklar ska få plats. Skåpet är modulanpassat och kan därför placeras mer platseffektivt på olika platser. En ljusindikation på handtaget visar om skåpet är ledigt eller upptaget och öppnas med en tagg som skannas på en RFID-läsare. / The project began as an open question in collaboration with a consulting company in product development to develop a more secure parking for bicycles. Therefore, a comprehensive feasibility study was performed to evaluate the bicycle values and to see potential development opportunities for different types of bicycle parking. Blidsberg mekaniska is a company that manufactures bicycle parking and other types of outdoor environment products. They were involved in the work and wanted to expand their range with a new bike box. The designprocess started with a marketreasearch with the aim to analyze cycle parks in a pre-study. During the pre-study demands was researched and formed a requirement specification. The creative work in the development of a new cycle park was helped by many creative methods that generated many concepts that later was compared in a matrix. The final concept was able to compete with the existing solutions. The result was a combination of already existing solutions. The bicycle locker does not take up more space than is necessary for most bicycles to fit in. The bicycle locker is modularly adapted and can therefore be placed more space efficiently in different places. A light indication on the handle indicates whether the bicycle locker is free or occupied and opened with a tag that is scanned on a RFID-reader.
62

ENVIRONMENTAL IMPACT ASSESSMENT AND IMPROVED DESIGN OF BIKE SHARING SYSTEMS FROM THE LIFE CYCLE PERSPECTIVE

Hao Luo (6617804) 10 June 2019 (has links)
<div>Bike sharing system (BSS) is growing worldwide. Although bike sharing is viewed as a sustainable transportation mode, it still has environmental footprints from its operation (e.g., bike rebalancing using automobiles) and upstream impacts (e.g., bike and docking station manufacturing). Thus, evaluating the environmental impacts of a BSS from the life cycle perspective is vital to inform decision making for the system design and operation. In this study, we conducted a comparative life cycle assessment (LCA) of station-based and dock-less BSS in the U.S. The results show that dock-less BSS has a greenhouse gas (GHG) emissions factor of 118 g CO2-eq/bike-km in the base scenario, which is 82% higher than the station-based system. Bike rebalancing is the main source of GHG emissions, accounting for 36% and 73% of the station-based and dock-less systems, respectively. However, station-based BSS has 54% higher total normalized environmental impacts (TNEI), compared to dock-less BSS. The dock manufacturing dominants the TNEI (61%) of station-based BSS and the bike manufacturing contributes 52% of TNEI in dock-less BSS. BSS can also bring environmental benefits through substituting different transportation modes. Car trip replacement rate is the most important factor. The results suggest four key approaches to improve BSS environmental performance: 1) optimizing the bike distribution and rebalancing route or repositioning bikes using more sustainable approaches, 2) incentivizing more private car users to switch to using BSSs, 3) prolonging lifespans of docking infrastructure to significantly reduce the TNEI of station-based systems, and 4) increasing the bike utilization efficiency to improve the environmental performance of dock-less systems.</div><div>To improve the design of current BSS from the life cycle perspective, we first proposed a simulation framework to find the minimal fleet size and their layout of the system. Then we did a tradeoff analysis between bike fleet size and the rebalancing frequency to investigate the GHG emission if we rebalance once, twice and three times a day. The optimal BSS design and operation strategies that can minimize system GHG emission are identified for a dock-less system in Xiamen, China. The results show that at most 15% and 13% of the existing fleet size is required to serve all the trip demand on weekday and weekend, if we have a well-designed bike layout. The tradeoff analysis shows that the GHG emission may increase if we continue to reduce the fleet size through more frequent rebalancing work. Rebalancing once a day during the night is the optimal strategy in the base scenario. We also tested the impacts of other key factors (e.g., rebalancing vehicle fleet size, vehicle capacity and multiple depots) on results. The analysis results showed that using fewer vehicles with larger capacity could help to further reduce the GHG emission of rebalancing work. Besides, setting 3 depots in the system can help to reduce 30% of the GHG emission compared with 1-depot case, which benefits from the decrease of the commuting trip distance between depot and the serve region.</div>
63

Ciclovias: Possibilidades de Implantação em Goiânia

Domingos, John Moreira 09 April 2012 (has links)
Made available in DSpace on 2016-08-10T10:49:49Z (GMT). No. of bitstreams: 1 JOHN MOREIRA DOMINGOS - PARTE 1.pdf: 12430925 bytes, checksum: eeca054f912c863b738537149b31db04 (MD5) Previous issue date: 2012-04-09 / Macro phenomenon as capitalism and the industrial revolution imposed drastic changes in the lives of huge populations. Urbanization, a major consequence of these, brought problems of all kinds. Among them, those related to urban mobility are presented as a complex challenge to be solved. As the object of study, it appears that the city of Goiânia in 2011 joined the group of five Brazilian cities with more than one million vehicles, with a rate of vehicles/capita of 0.95 (DENATRAN, 2011e IBGE, 2010 ), as the fifth capital with a higher mortality rate in the total of accidents and motorcycle accidents seventh (www.samugoiania.com.br). But in 50 years, was one of Goiânia Brazilian cities that had more bikes for people (DEUS and BARREIRA, 2006), has been called the Brazilian capital of bike (OPTION JOURNAL, 1980), in 1980 there were 47.783 daily movements by bicycles and; 50,000 users, representing 23% of the economically active population of the city (IPLAN, 1981). Therefore, this dissertation presents the benefits of bicycle use and road cycle infrastructure as an important strategy in addressing conflicts of urban mobility and also seeks to highlight the call and the historical roots cycling of Goiânia. / Macrofenômenos como capitalismo e revolução industrial impuseram drásticas mudanças na vida de imensas populações. A urbanização, uma das principais consequências desses, trouxe problemas de toda ordem. Dentre eles, os relacionados à mobilidade urbana se apresentam como um complexo desafio a ser equacionado. Como objeto de estudo, apresenta-se a cidade de Goiânia que em 2011 entrou para o grupo das cinco cidades brasileiras com mais de um milhão de veículos, com uma taxa de veículos/habitante de 0,95 (DENATRAN, 2011 e IBGE, 2010), como a quinta capital com maior taxa de mortalidade no total dos acidentes e a sétima dos acidentes com motos (www.samugoiania.com.br). Porém, nos anos 50, Goiânia era uma das cidades brasileiras que mais possuíam bicicletas por habitantes (DEUS e BARREIRA, 2006); já foi denominada a capital brasileira das bicicletas (JORNAL OPÇÃO, 1980); em 1980 havia 47.783 deslocamentos diários por bicicletas e; 50.000 usuários, que representavam 23% da população economicamente ativa da cidade, (IPLAN, 1981). Por tanto, esta dissertação apresenta os benefícios do uso da bicicleta e das infra-estruturas cicloviárias como importante estratégia no equacionamento dos conflitos de mobilidade urbana e busca também ressaltar a vocação e as raízes históricas ciclísticas de Goiânia.
64

Essays on Environmental Policy: Design and Evaluation

Cornago, Elisabetta 15 March 2019 (has links) (PDF)
In this thesis, I analyze the impacts of the design and implementation of different environmental policy tools from a theoretical and empirical perspective: certificates providing information on the energy performance of buildings (chapter 1); urban road pricing schemes such as congestion charges (chapter 2); quantity-based policy tools to support production with non-polluting technologies (chapter 3).In chapter 1, co-authored with Luisa Dressler, we study how energy performance certificates (EPCs) impact the residential rental market. These certificates can help solve information asymmetries between landlords and tenants about the thermal quality of dwellings for rent, which, in turn, is expected to facilitate investment aimed at improving dwellings' energy performance. However, disclosure of EPCs is often incomplete, which hampers their effectiveness in relieving such information asymmetries. Moreover, even when a certificate is available, landlords do not always disclose it. This contradicts the so-called information unraveling result, according to which all landlords should disclose quality information unless it is costly to do so: in such a setting, information eventually unravels. Using a cross-sectional dataset of residential rental advertisements from the Belgian region of Brussels, we empirically evaluate incentives to disclose energy performance ratings. We find that two fundamental assumptions underlying the unraveling result are not confirmed in our setting: firstly, tenants value energy performance of rental property only when dwellings are of very high quality; secondly, tenants do not appear to rationally adjust their expectations when faced with dwellings that withhold their energy performance rating. Finally, we formulate specific policy advice for reforming EPC mechanisms to increase disclosure rates.In chapter 2, I study how urban congestion pricing impacts the use of sustainable mobility options such as bike sharing, presenting evidence from the city of Milan, Italy.As concern for air pollution grows in cities across the world, policies such as urban road pricing are rolled out to induce urban residents to opt for greener transport options. While several papers have analyzed the impact of urban road pricing on air pollution and on car use, this is the first analysis of its impact on sustainable travel behaviors, such as the use of bike sharing.I extend a stylized theoretical model of travel behavior to formalize the drivers of bike-sharing demand. Then, I exploit a panel dataset covering all bike-sharing trips carried out over an 8-year period in the city of Milan to estimate the impact of congestion pricing on bike-sharing use. The empirical strategy I employ in this study is based on the sudden suspension and reintroduction of congestion pricing, which generate a quasi-experimental setting. Adopting an event study approach, I find that suspending the congestion charge reduces daily bike-sharing traffic by about 5% in the short run. I show that, in Milan, congestion pricing mainly impacts bike-sharing use through the reduction of road traffic congestion, which makes cycling safer and more pleasant. The direct effect of the increased relative cost of car use is secondary in individual decisions to use bike-sharing. The role of these effects is likely to be context-specific, as they may be affected by the baseline level of urban congestion, the broader policy mix affecting the cost of driving and the specific design of the congestion pricing scheme.In chapter 3, co-authored with Renaud Foucart, we study the impact of different quantity-based tools that governments can use to support the production of homogeneous goods through clean rather than polluting inputs in a setting where production costs are uncertain.In recent years, many sectors have been disrupted by clean innovation, as clean inputs have emerged as close substitutes of polluting ones: for example, in the power sector renewable energy sources are increasingly used for electricity generation instead of fossil fuels. Whenever the negative externalities caused by polluting incumbent technologies are not internalized in production costs, emerging clean technologies are left at a disadvantage. For this reason, governments may want to design policy support schemes for emerging clean technologies.We develop a theoretical framework in which well-established polluting technologies entail known production and pollution costs, while using emerging green technologies requires higher, steeper and uncertain production costs. In this context, a government chooses between a range of quantity-based instruments to support the deployment of clean technologies based on cost estimates, as costs of production with green inputs are uncertain.We show that a cap on production with polluting inputs is the least distortionary among quantity instruments; next is a mandatory share of production with green inputs out of total production. Setting a policy objective in terms of a precise level of green inputs for production is the least efficient policy approach. This ranking results from the so-called “technology effect”, which determines the extent to which the market corrects cost estimation errors after real costs are observed. / Doctorat en Sciences économiques et de gestion / info:eu-repo/semantics/nonPublished
65

Prescribe a bike: reducing income-based disparities in bike access for health promotion and active transport through primary care

Ryan, Kathleen Mary 22 June 2016 (has links)
Low-income groups have greater potential to gain from incorporating health promotion into daily living using bike-share to increase physical activity and expand transport options. The potential is unmet because of socioeconomics and access. Disproportionate uptake of bike-share by higher income individuals widens the gaps in health equity and transportation equity as bike-share use over-represents males with more resources, less need, and lower health risk. The Prescribe a Bike (RxBike) program, a key focus of this study, is a partnership between primary care providers (PCPs) at an urban safety net hospital and the city’s existing income-based, subsidized bike-share membership. Three studies using quantitative and qualitative methods were performed to: examine utilization of bike-share by Boston residents among subsidized and non-subsidized members; examine perceived attributes of the RxBike program by Boston Medical Center (BMC) PCPs; and evaluate BMC patient referrals. The overarching conceptual model uses elements of theories from health services and organizational behavior, in a public health framework. Analysis of Boston resident utilization at the trip-level (2012-2015) demonstrated overall ridership was increasingly by males and residents of more advantaged neighborhoods. Subsidized members had significantly higher likelihood of living in neighborhoods with socioeconomic and health disadvantage, and less gender disparity when compared to non-subsidized members. The impact was minimal because subsidized members made only 7.17% of trips. The survey of PCPs revealed mismatch between highly favorable opinion of RxBike appropriateness and lower intent to refer. Female gender and not being an urban biker predicted lower likelihood of intent to refer. Examination of open-ended survey comments mirrored quantitative data and expanded on the range of provider biking safety concerns in Boston. From 2013-2015, 27 BMC providers made only 72 referrals to RxBike. Patients referred had high cardiovascular health risk, resided in neighborhoods with extremely high levels of disadvantage, and in neighborhoods without meaningful access to bike-share kiosks. Overall, the subsidized membership extends reach of bike-share to residents of neighborhoods with more health and socioeconomic risk than the rest of the city; RxBike has strong potential to impact this vulnerable population. The most critical matters for program success are safety and neighborhood access.
66

Improving Service Level of Free-Floating Bike Sharing Systems

Pal, Aritra 13 November 2017 (has links)
Bike Sharing is a sustainable mode of urban mobility, not only for regular commuters but also for casual users and tourists. Free-floating bike sharing (FFBS) is an innovative bike sharing model, which saves on start-up cost, prevents bike theft, and offers significant opportunities for smart management by tracking bikes in real-time with built-in GPS. Efficient management of a FFBS requires: 1) analyzing its mobility patterns and spatio-temporal imbalance of supply and demand of bikes, 2) developing strategies to mitigate such imbalances, and 3) understanding the causes of a bike getting damaged and developing strategies to minimize them. All of these operational management problems are successfully addressed in this dissertation, using tools from Operations Research, Statistical and Machine Learning and using Share-A-Bull Bike FFBS and Divvy station-based bike sharing system as case studies.
67

From vision to prototype : Virtual road racing / Från idé till prototyp : Virtuell cykling

Östlund, Eric Chung Anders January 2005 (has links)
<p>Riding a stationary exercise bike regularly can lead to many health benefits such as stronger muscles, higher metabolism and reduced body fat percentage to mention a few. The biggest drawback is that training on a stationary exercise bike can be immensely boring with no stimulation or amusement factor. </p><p>This thesis presents the development of a prototype, a road racing simulator that makes training on an exercise bike more stimulating. The prototype consists of an exercise bike and a computer game. It also features a network option, making it possible to race other users, multi player style. The purpose is to make home training on the exercise bike more amusing, enjoyable and maybe even challenging. </p><p>The focus in this report lies mainly on the graphics and network parts but all steps in producing the prototype are described so the reader can get a complete picture of the project.</p>
68

Evaluation of performance of a smartphone application for measuring bike paths’ condition

Erlandsson, Jonas January 2013 (has links)
There are several methods to measure surface evenness for car roads, but almost none for bike paths. Accordingly, VTI (the Swedish National Road and Transport Research Institute) have created a smartphone application which uses the accelerometers in the phone to measure the vibration from the road. This report’s aim is to analyze the data collected using this application, investigate if the data is repeatable, to find factors that are important for evenness and perform classification of bike paths as even or wiggly. Two main methods were used, Gaussian process and wavelets. Gaussian process was used to classify bike paths and wavelets to investigate the repeatability and see how many trips are needed to get a consistent result. The results show that the two different smartphones gave quite different results; one smartphone indicated almost twice as high RMS values (measure of vibration) than the other. The GPS positions of smartphones were quite good, except under a tunnel and close to high buildings. Some short section of the road gave very high or very low RMS values, but the general standard of all investigated bike paths were too even to detect any significant differences between the paths. The results show that there’s some unexplained variance in the turns, but the effect of the turns hasn’t been tested. The wavelets analysis show that around 15 trips were needed to get a consistent result. The report contains a description of a designed experiment that will continue this project. This new data will be collected in a more carefully to make a better separation between good and bad cycle routes by the RMS value. / <p>Uppdragsgivare: VTI (Anna Niska och Leif Sjögren)</p>
69

Electric Bicycle Design

Tovar López, Carlos January 2009 (has links)
The thesis consists of the design of an electric bike. Based on the analysis of the needs arising from urban transport in Sweden and its people.We wanted to develop a bicycle that could be manufactured in the coming years and be widely accepted by the Swedish population and later also in Europe.
70

A glimpse of Bike-n-Bus: an exploratory survey of the United States

McBurney, Andrew Patrick 09 April 2012 (has links)
Bike-n-Bus includes any number of methods where bicycle serves as the access mode to some form of bus transit. This study examines bike-n-bus operations in the United States based on telephone interviews with transit professionals from 33 transit agencies across the lower 48 states. It reviews past trends in research and gives some history of bike-n-bus in the U.S. and abroad. A brief explanation of methodology is followed by a description of the various facets of U.S. bike-n-bus operations, based on both interviews and the literature, with commentary by survey respondents. The study ends with a long term vision for bike-n-bus based on the characteristics of that mode-couple. Conclusions are addressed to various audiences: transit agency, community leader/ policy maker, and researcher. Included are suggestions for possible next steps in research and implementation. These findings would be of interest to those studying transit and bicycle travel, developing travel demand models, managing a transit agency, or those with influence over bicycle policy and infrastructure. Most transit agencies have installed front-mounted bicycle racks on their entire bus fleet, and expressed satisfaction that the amenity accommodates bicyclists. However, agencies have made only moderate efforts to follow-up on this success. Studies suggest that cycling to transit can be competitive with the private automobile in journey-to-work trips and attracts new riders to transit. Better bicycling infrastructure is the most significant way to increase the number of bike-n-bus riders. However, transit agencies seem reluctant to support these improvements.

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