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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.
111

Smart City Energy Efficient Multi-Modal Transportation Modeling and Route Planning

Ghanem, Ahmed Mohamed Abdelaleem 25 June 2020 (has links)
As concerns about climate change increase, many people are calling for reductions in the use of fossil fuels and encouraging a shift to more sustainable and less polluting transportation modes. Cities and urban areas are more concerned because their population currently comprises over half of the world's population. Sustainable transportation modes such as cycling, walking, and use of public transit and electric vehicles can benefit the environment in many ways, including a reduction in toxic greenhouse gas (GHG) emissions and noise levels. In order to enhance the trend of using sustainable modes of transportation, tools, measures, and planning techniques similar to those used for vehicular transportation need to be developed. In this dissertation, we consider four problems in the context of different sustainable modes of transportation, namely, cycling, rail, public transit, and ridesharing. We develop different models to predict bike travel times for use in bike share systems (BSSs) using random forest (RF), least square boosting (LSBoost), and artificial neural network (ANN) techniques. We also use cycling Global Positioning System (GPS) data collected from 10 people (3 females and 7 males) to study cyclists' acceleration/deceleration behavior. Moreover, we develop a continuous rail transit simulator (RailSIM) intended for multi-modal energy-efficient routing applications. Finally, we propose a dynamic trip planning system that integrates ridesharing and public transit. The work done in this dissertation can help encouraging more people to move to more sustainable modes of transportation. / Doctor of Philosophy / As concerns about climate change increase, many people are calling for reductions in the use of fossil fuels and encouraging a shift to more sustainable and less polluting transportation modes. Cities and urban areas are more concerned because their population currently comprises over half of the world's population. Sustainable transportation modes such as cycling, walking, and use of public transit and electric vehicles can benefit the environment in many ways, including a reduction of toxic greenhouse gas (GHG) emissions and noise levels. In order to enhance the trend of using sustainable modes of transportation, tools, measures, and planning techniques similar to those used for vehicular transportation need to be developed. In this dissertation, we consider four problems in the context of different sustainable modes of transportation, namely, cycling, rail, public transit, and ridesharing. We develop different models to predict bike travel times in bike share systems (BSSs) using machine learning techniques. We also use cycling Global Positioning System (GPS) data collected from 10 people (3 females and 7 males) to study cyclists' acceleration/deceleration behavior. Moreover, we develop a continuous rail transit simulator (RailSIM) intended for multi-modal energy-efficient routing applications. Finally, we propose a dynamic trip planning system that integrates ridesharing and public transit. The work done in this dissertation can help encouraging more people to move to more sustainable modes of transportation.
112

Strategic Design of Smart Bike-Sharing Systems for Smart Cities

Ashqar, Huthaifa Issam 25 October 2018 (has links)
Traffic congestion has become one of the major challenging problems of modern life in many urban areas. This growing problem leads to negative environmental impacts, wasted fuel, lost productivity, and increased travel time. In big cities, trains and buses bring riders to transit stations near shopping and employment centers, but riders then need another transportation mode to reach their final destination, which is known as the last mile problem. A smart bike-sharing system (BSS) can help address this problem and encourage more people to ride public transportation, thus relieving traffic congestion. At the strategic level, we start with proposing a novel two-layer hierarchical classifier that increases the accuracy of traditional transportation mode classification algorithms. In the transportation sector, researchers can use smartphones to track and obtain information of multi-mode trips. These data can be used to recognize the user's transportation mode, which can be then utilized in several different applications; such as planning new BSS instead of using costly surveys. Next, a new method is proposed to quantify the effect of several factors such as weather conditions on the prediction of bike counts at each station. The proposed approach is promising to quantify the effect of various features on BSSs in cases of large networks with big data. Third, these resulted significant features were used to develop state-of-the-art toolbox algorithms to operate BSSs efficiently at two levels: network and station. Finally, we proposed a quality-of-service (QoS) measurement, namely Optimal Occupancy, which considers the impact of inhomogeneity in a BSS. We used one of toolbox algorithms modeled earlier to estimate the proposed QoS. Results revealed that the Optimal Occupancy is beneficial and outperforms the traditionally-known QoS measurement. / PHD / A growing population, with more people living in cities, has led to increased pollution, noise, congestion, and greenhouse gas emissions. One possible approach to mitigating these problems is encouraging the use of bike-sharing systems (BSSs). BSSs are an integral part of urban mobility in many cities and are sustainable and environmentally friendly. As urban density increases, it is likely that more BSSs will appear due to their relatively low capital and operational costs, ease of installation, pedal assistance for people who are physically unable to pedal for long distances or on difficult terrain, and the ability to track bikes in some cases. This dissertation is a building block for a smart BSS in the strategic level, which could be used in real and different applications. The main aims of the dissertation are to boost the redistribution operation, to gain new insights into and correlations between bike demand and other factors, and to support policy makers and operators in making good decisions regarding planning new or existing BSS. This dissertation makes many significant contributions. These contributions include novel methods, measurements, and applications using machine learning and statistical learning techniques in order to design a smart BSS. We start with proposing a novel framework that increases the accuracy of traditional transportation mode classification algorithms. In the transportation sector, researchers can use smartphones to track and obtain information of multi-mode trips. These data can be used to recognize the user’s transportation mode, which can be then used in planning new BSS. Next, a new method is proposed to quantify the effect of several factors such as weather conditions on the prediction of bike station counts. Third, we use state-of-the-art data analytics to develop a toolbox to operate BSSs efficiently at two levels: network and station. Finally, we propose a quality-of-service (QoS) measurement, which considers the impact of inhomogeneity of BSS properties.
113

Ermittlung und Konzeption eines 85 %-Bemessungsfahrzeugs für Lastenfahrräder

Fassnacht, Lukas, Schäfer, Petra, Knese, Dennis 16 May 2024 (has links)
Dieser Artikel beschreibt die Konzeption eines Bemessungsfahrzeugs für Lastenfahrräder anhand der Datenerfassung von 103 Fahrzeugen. Ziel war es, aus einer Vielzahl von Lastenfahrrädern, die im Privatsektor genutzt werden, ein „repräsentatives“ Bemessungsfahrzeug zu erstellen, das für verkehrsplanerische Maßnahmen verwendet werden kann. Dazu wurde eine Datenerhebung anhand von Online-Recherchen sowie der Vermessung von Lastenfahrrädern durchgeführt. Aus dieser Datengrundlage konnten 42 unterschiedliche Lastenfahrrad-Modelle mit vollständigen Daten für die Analyse genutzt werden. Auf Basis dieser Analyse wurde ein Bemessungslastenfahrrad entwickelt, das 2,60 Meter lang ist, einen Radstand von exakt 2 Metern besitzt, 1,20 Meter hoch ist, eine 70 Zentimeter breite Transportbox und einen 89 Zentimeter breiten Lenker aufweist. Die Nutzung des entwickelten Bemessungslastenfahrrads ist in der Verkehrsplanung, beispielsweise zur Dimensionierung der Breiten von Radwegen, Abständen zwischen Pollern und Umlaufsperren oder Parkmöglichkeiten für Lastenfahrräder, schon jetzt nutzbar, sollte aber durch eine Hüllkurvensimulation und eine Ausweitung der Stichprobe ergänzt werden.:1. Einleitung 2. Bemessungsfahrzeuge in der Verkehrsplanung 2.1 Relevanz in der Verkehrsplanung 2.2 Grundlagen von Bemessungsfahrzeugen: vom PKW zum Lastenfahrrad 3. Datengrundlage und Methodik 3.1 Angewandte Methodik zur Entwicklung eines Bemessungslastenfahrrads 3.2 Erstellung der Datengrundlage 4. Ergebnisse der Untersuchung 4.1 Auswertung der Lastenfahrrad-Maße 4.2 Erstellung des 85 %-Bemessungsfahrzeugs 5. Schlussfolgerung Literaturverzeichnis / This paper describes the design of a dimensioning vehicle for cargo bikes based on data collection of 103 vehicles. The goal was to create a dimensioning vehicle from a large number of cargo bikes used in the private sector that can be used for transport planning tasks. To accomplish this, a data collection was conducted using online research as well as measuring cargo bikes. From this database, 42 different cargo bike models with a complete dataset could be used for the analysis. From the analysis, it was possible to develop a dimensioning cargo bike, which is 2.60 meters long, has a wheelbase of exactly 2 meters, is 1.20 meters high, has a 70 centimeter wide transport box and 89-centimeter-wide handlebars. The developed dimensioning cargo bike is already usable in transport planning, for example for dimensioning the widths of bike lanes, distances between bollards and circulation grids, or parking facilities for cargo bikes, but should be supplemented by an envelope curve simulation and an expansion of the sample.:1. Einleitung 2. Bemessungsfahrzeuge in der Verkehrsplanung 2.1 Relevanz in der Verkehrsplanung 2.2 Grundlagen von Bemessungsfahrzeugen: vom PKW zum Lastenfahrrad 3. Datengrundlage und Methodik 3.1 Angewandte Methodik zur Entwicklung eines Bemessungslastenfahrrads 3.2 Erstellung der Datengrundlage 4. Ergebnisse der Untersuchung 4.1 Auswertung der Lastenfahrrad-Maße 4.2 Erstellung des 85 %-Bemessungsfahrzeugs 5. Schlussfolgerung Literaturverzeichnis
114

Towards an Integrated Approach to Verification and Model-Based Testing in System Engineering

Lefticaru, Raluca, Konur, Savas, Yildirim, Unal, Uddin, Amad, Campean, Felician, Gheorghe, Marian 22 April 2017 (has links)
Yes / Engineering design in general and system design of embedded software have a direct impact on the final engineering product and the software implementation, respectively. Guaranteeing that the models utilised meet the specified requirements is beneficial in detecting misbehaviour and software flaws. This requires an integrated approach, combining verification and model-based testing methodology and notations and methods from system engineering and software engineering. In this paper, we propose a model-based approach integrating various notations utilised in the functional design of complex systems with formal verification and testing. We illustrate our approach on the cruise control system of an e-Bike case study.
115

Development of crash test methodology for child bike trailers : A study on methodology development for crash testing of child bike trailers at Thule Test Center

Egerhag, Johannes, Johansson, Karl January 2024 (has links)
The purpose of this study is to develop and analyze the possibilities of implementing a new crash test method for child bike trailers based on StVZO §67 Explanation 19 Appendix 2 at Thule Test Center or use an alternative method. The study is based on the following three problem statements: can a new method based on StVZO §67 Explanation 19 Appendix 2 replace TÜV and RISE test methods? Is it possible to implement a new test method in Thule Crash Lab using the acceleration sled track or using a different approach? How can crash testing contribute to optimizing the development of child bike trailers? This study began with background information and the problem description of Thule’s lack of test method and their need for a new alternative. The theorical background provides information about testing for product development. It also provides information about StVZO §67 Explanation 19 Appendix 2 which will be the basis for the study and the previous test methods Thule has used, which were RISE and TÜV.  Observations, analyzes and an interview from the previous test methods established the foundation for the concept study which included brainstorming sessions to generate concepts for the new test method. The concepts consisted both of methods with and without the acceleration sled track. Several workshops served as concept selections which filtered out concepts that exceeded limitations of the facilities at Thule Test Center. The concepts that could not fulfill the requirements from StVZO §67 Explanation 19 Appendix 2 was also filtered out.  To find out if the acceleration sled could be used as a test method, different tests were involved which included evaluation of test impulses and crash tests with handmade fixtures for the child bike trailer. This was carried out to ensure that the crash sled could operate under the variables that was calculated in preparation for the test and that the fixtures could handle the accelerations.  The study also included discussions and conclusions with suggestions for modifications to the concepts that could not be directly implemented due to the limitations in Thule facilities. Some of the modifications were also taken up as suggestions for further research. The study also included comparison between internal and external testing. The comparison explained the importance for Thule to have an internal test method and generally an alternative for crash testing their child bike trailers. As presented in the study, crash testing is crucial for an optimized development of new child bike trailers to ensure safe, qualitative and durable child bike trailers. It is also crucial to stay competitive in the market. To validate stresses and forces subjected onto the construction of the final test method, static calculations were performed which gave an indication of what dimensions the beams for the construction could have. As discussed, dynamic calculations could have been done to achieve a more precise and accurate result.  The final test method is an example of what Thule could use for crash testing their child bike trailers with the requirements from StVZO §67 Explanation 19 Appendix 2. Design changes are possible if it were to be implemented and the new test method gives Thule an internally option.
116

Método para definição de rede de rotas cicláveis em áreas urbanas de cidades de pequeno porte: um estudo de caso para a cidade de Bariri-SP / Method for the definition of cycling routes network in urban areas of small-sized cities: a case study for the city of Bariri-SP

Monari, Marcelo 11 May 2018 (has links)
A Lei nº 12.587, de 3 de janeiro de 2012, obriga a todos os municípios brasileiros com população superior a 20 mil habitantes a elaborarem um plano de mobilidade urbana integrado e compatível com seus respectivos planos diretores ou neles inseridos, priorizando os modos de transporte não motorizados. Apesar da exigência legal, muitos municípios brasileiros, principalmente os de pequeno porte, não dispõem de diretrizes para o desenvolvimento de sistemas cicloviários. O objetivo deste trabalho é elaborar um método para definição de rede de rotas cicláveis em áreas urbanas de cidades de pequeno porte, cuja ideia central é avaliar segmentos viários com relação a fatores que influenciam no uso da bicicleta como modo de transporte urbano, tais como declividade, disponibilidade de espaço e influência exercida pelos veículos motorizados. O método proposto é subdividido em cinco etapas: (1) caracterização da área de estudo; (2) análise dos polos geradores de tráfego por bicicletas; (3) avaliação da compatibilidade das vias com o transporte cicloviário; (4) identificação das rotas cicláveis; e (5) definição da rede. Os modelos escolhidos para a verificação do perfil topográfico e para a avaliação da qualidade de serviço das vias de tráfego para o transporte cicloviário são, respectivamente, o modelo da AASHTO (1999) e o modelo de Sorton e Walsh (1994). Foi realizado um estudo de caso na cidade de Bariri-SP. Os resultados mostram que as rotas cicláveis identificadas priorizam segmentos com infraestrutura cicloviária pré-existente, assim como locais que necessitam de facilidades para ciclistas, como ciclofaixas e ciclovias, e dispõem de espaço para sua inserção. Quanto aos espaços compartilhados, nota-se uma tendência de que as rotas cicláveis sejam compostas por segmentos com boas avaliações globais de nível de estresse. A rede de rotas cicláveis definida para a cidade de Bariri-SP é formada por 19 eixos viários distribuídos de maneira a atender toda a área delimitada para estudo. / The law 12.587 of January 3rd, 2012, enforces every Brazilian city over 20,000 inhabitants to elaborate an urban mobility plan integrated and compatible with their respective master plans, giving priority to non-motorized transportation modes. Despite legal enforcement, many Brazilian cities, mainly the small ones, are not given proper guidelines to develop cycling systems. This research\'s goal is to elaborate a method to define a cycling routes network in urban areas of small-sized cities, whose main point is to assess road segments according to factors that influence the bicycle use as an urban transportation mode, such as slope, space availability to stand cycling transportation as well as motorized vehicles influence on bicycle traffic. The proposed method splits into five steps: (1) study area characterization; (2) analysis of bicycle traffic generator poles; (3) evaluation of the streets compatibility with bicycle transportation; (4) cycling routes identification; (5) network definition. The chosen models for topographic verification and service quality ratings of the roads for cycling transportation are, respectively, the AASHTO\'s (1999) model and the Sorton and Walsh\'s (1994) model. A case study was carried out in the city of Bariri-SP. The results of the proposed method\'s application show that the identified cycling routes prioritize road segments with cycling infrastructure already existent, as well as places in need of cycling facilities, such as cycle lanes and cycle paths, that have available space to accommodate them. Concerning shared spaces, there\'s a trend that cycling routes are composed of segments with good global stress level evaluations. The cycling routes network defined in the city of Bariri-SP is made up by 19 road axes widespread to serve the whole area delimited for study.
117

Método para definição de rede de rotas cicláveis em áreas urbanas de cidades de pequeno porte: um estudo de caso para a cidade de Bariri-SP / Method for the definition of cycling routes network in urban areas of small-sized cities: a case study for the city of Bariri-SP

Marcelo Monari 11 May 2018 (has links)
A Lei nº 12.587, de 3 de janeiro de 2012, obriga a todos os municípios brasileiros com população superior a 20 mil habitantes a elaborarem um plano de mobilidade urbana integrado e compatível com seus respectivos planos diretores ou neles inseridos, priorizando os modos de transporte não motorizados. Apesar da exigência legal, muitos municípios brasileiros, principalmente os de pequeno porte, não dispõem de diretrizes para o desenvolvimento de sistemas cicloviários. O objetivo deste trabalho é elaborar um método para definição de rede de rotas cicláveis em áreas urbanas de cidades de pequeno porte, cuja ideia central é avaliar segmentos viários com relação a fatores que influenciam no uso da bicicleta como modo de transporte urbano, tais como declividade, disponibilidade de espaço e influência exercida pelos veículos motorizados. O método proposto é subdividido em cinco etapas: (1) caracterização da área de estudo; (2) análise dos polos geradores de tráfego por bicicletas; (3) avaliação da compatibilidade das vias com o transporte cicloviário; (4) identificação das rotas cicláveis; e (5) definição da rede. Os modelos escolhidos para a verificação do perfil topográfico e para a avaliação da qualidade de serviço das vias de tráfego para o transporte cicloviário são, respectivamente, o modelo da AASHTO (1999) e o modelo de Sorton e Walsh (1994). Foi realizado um estudo de caso na cidade de Bariri-SP. Os resultados mostram que as rotas cicláveis identificadas priorizam segmentos com infraestrutura cicloviária pré-existente, assim como locais que necessitam de facilidades para ciclistas, como ciclofaixas e ciclovias, e dispõem de espaço para sua inserção. Quanto aos espaços compartilhados, nota-se uma tendência de que as rotas cicláveis sejam compostas por segmentos com boas avaliações globais de nível de estresse. A rede de rotas cicláveis definida para a cidade de Bariri-SP é formada por 19 eixos viários distribuídos de maneira a atender toda a área delimitada para estudo. / The law 12.587 of January 3rd, 2012, enforces every Brazilian city over 20,000 inhabitants to elaborate an urban mobility plan integrated and compatible with their respective master plans, giving priority to non-motorized transportation modes. Despite legal enforcement, many Brazilian cities, mainly the small ones, are not given proper guidelines to develop cycling systems. This research\'s goal is to elaborate a method to define a cycling routes network in urban areas of small-sized cities, whose main point is to assess road segments according to factors that influence the bicycle use as an urban transportation mode, such as slope, space availability to stand cycling transportation as well as motorized vehicles influence on bicycle traffic. The proposed method splits into five steps: (1) study area characterization; (2) analysis of bicycle traffic generator poles; (3) evaluation of the streets compatibility with bicycle transportation; (4) cycling routes identification; (5) network definition. The chosen models for topographic verification and service quality ratings of the roads for cycling transportation are, respectively, the AASHTO\'s (1999) model and the Sorton and Walsh\'s (1994) model. A case study was carried out in the city of Bariri-SP. The results of the proposed method\'s application show that the identified cycling routes prioritize road segments with cycling infrastructure already existent, as well as places in need of cycling facilities, such as cycle lanes and cycle paths, that have available space to accommodate them. Concerning shared spaces, there\'s a trend that cycling routes are composed of segments with good global stress level evaluations. The cycling routes network defined in the city of Bariri-SP is made up by 19 road axes widespread to serve the whole area delimited for study.
118

Návrh rámu horského kola a jeho deformačně napěťová analýza pomocí MKP / Design of mountain-bike crossbar and its FEM analysis

Jelínek, Martin January 2008 (has links)
The aim of this diploma thesis is the part of evolution of the new bicycle frame for mountain biking, category enduro. The first part of this thesis is focused on creating dimensional modified model of the bike frame in CAD system SolidWorks. Subsequently this frame will be detailed by FEM analysis in software ANSYS Workbench and determine boundary conditions for this analysis. The final part is about visualization of the new bike frame.
119

Applying strategic design to stand out in the cargo bike market. : Development of a cargo bike for non-cargo bike people. / Tillämpning av strategisk design för att sticka ut på lastcykelmarknaden. : Utveckling av en lastcykel för lastcykelskeptiska.

Mikkelsen, Anna, Wernberg, Moa January 2019 (has links)
This report presents a master’s degree project in Integrated Product Design at KTH Royal Institute of Technology in Stockholm, on behalf of the company Rawbike. The purpose was tod evelop a design and construction proposal for a cargo bike from a strategic market perspective, that could broaden the audience of Rawbike to include more female users. The Rawhauler is a powerful cargo bike with attitude for those who need an agile, multifunctional and modular cargo solution. The Rawhauler makes it possible to carry heavyloads and climb the steepest of hills while having a pleasant biking experience in crowded commuter traffic. Literature studies and strategic tools were used to design a branding strategy where a smallcompany like Rawbike can develop a strong brand to stand out in the crowd. User centredstudies were conducted to ensure a product well adapted to the needs and wants of its users. The insights gained from these two fields were then used to develop a competitive concept thatboth extended the existing portfolio and appealed to the whole Rawbike community, regardlessof gender. / I denna rapport redovisas ett examensarbete på mastersnivå inom utbildningen Teknisk Design på Kungliga Tekniska Högskolan i Stockholm, på uppdrag av företaget Rawbike. Syftet med projektarbetet var att skapa ett marknadsstrategiskt design- och konstruktionsförslag på en lastcykel som skulle kunna bredda Rawbikes befintliga publik och inkludera fler kvinnliga användare. Rawhaulern är en kraftfull lastcykel med attityd för dig som behöver en smidig, multifunktionell och anpassningsbar lastlösning. Rawhaulerns möjliggör för att kunna ta rejält med last där du kan bestiga även de brantaste av backar och ha en härlig cykelupplevelse i trång cykelpendlingstrafik. Litteraturstudier och marknadsstrategiska verktyg användes för att utforma en varumärkesstrategi där ett litet företag som Rawbike kan sticka ut ur mängden med ett starktvarumärke. Användarcentrerade studier genomfördes för att kunna skapa en produkt välförankrad i användarens behov och begär. Insikterna från dessa två områden användes sedan för ta fram ett konkurrenskraftigt koncept som både utökade befintlig produktportfölj och kunde gå hem hos alla, oavsett kön, i Rawbikes community.
120

Ridazz, Wrenches, and Wonks: A Revolution on Two Wheels Rolls Into Los Angeles

Strauss, Donald Parker 25 March 2015 (has links)
No description available.

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