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1
Epp, Viktor, Özgül Gün, Hans-Jörg Deiseroth, and Martin Wilkening. "Extreme mobility." Universitätsbibliothek Leipzig, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-183736.
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2
Poirel, Maylis. "Produire les usagers : analyse du travail quotidien des professionnels de la mobilité." Thesis, Paris Est, 2018. http://www.theses.fr/2018PESC1046/document.
Full textAbstract:
La prise en compte des usagers est aujourd'hui incontournable pour les professionnels en charge de la production des services de mobilité. Or, qu'il s'agisse de services traditionnels ou de nouveaux services collaboratifs comme le covoiturage, l'essentiel du travail de ces professionnels se déroule en l'absence des usagers, inaccessibles ou encore inexistants. La prise en compte des usagers se traduit alors par la mise en place d'outils variés (enquête, concertation, traitement des réclamations, communication, système d'information, etc.) destinés à représenter les usagers dans les différentes dimensions de la production du service. Au croisement d'approches interactionniste, sociotechnique et communicationnelle, cette thèse propose une lecture unifiée de ces divers outils de prise en compte des usagers en tant que travail collectif de construction d'une fiction de l'usager. Les professionnels élaborent cette fiction à l'articulation de leur travail d'interaction avec les usagers pendant lequel ils les mettent en scène et de leur travail de réflexivité pendant lequel ils les mettent en récit. Cette recherche repose sur une enquête qualitative menée chez deux producteurs franciliens de services de mobilité, constituée d'observations participantes de situations de travail et d'entretiens semi-directifs. Le premier cas est celui de l'autorité organisatrice de transport d'Île-de-France, suivie dans ses missions d'organisation du développement et de l'exploitation des services régionaux de transports collectifs. Le deuxième est celui d'une jeune start-up de covoiturage courte distance analysée au moment du lancement d'une expérimentation sur un territoire en grande couronne en partenariat avec les collectivités localesIt is now essential for professionals in charge of the mobility services production to take into account their users. However, most of the time they work in the absence of users : in the case of classic services, the users are inaccessible, and in the case of emerging collaborative services such as carpooling, they don't exist yet. Professionals then use various devices, such as surveys, consultation, claims processing, communication, or information system, in order to represent the users in the different dimensions of the mobility services production. This thesis research relies on interactionist, sociotechnical and commmunication approaches in order to give a global understanding of the production of these various devices generally taken separately. The main argument is that the professionals build a fiction in which the users become characters: they go back and forth between staging interactions with the users and reflecting on them through storytelling.This research relies on a qualitative study with two mobility services producers in the Parisian region based on participant observation of work situations and semi-structured interviews with professionals. The first one is the regional Public Transport Authority in charge of the design and the operation of the regional public transport services. The second one is a short distance carpooling start-up launching an experiment in partnership with local authorities in the outer suburbs of the metropolitan area
3
Lam, Wing-yee Winnie, and 林泳怡. "Individual mobility for socially sustainable transport." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2012. http://hub.hku.hk/bib/B47752889.
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A socially sustainable transport system has to make sure that opportunities are accessible to all. The social dimension is important as transport-related barriers can contribute to social injustice. A well-functioning transport system should promote greater equity by linking people and places together. The discussion in this thesis revolves around the main concept of individual mobility. It refers to the ease with which an individual can move from one place to another to access opportunities. The main research objective of the thesis is to investigate the factors affecting individual mobility of three selected transport-disadvantaged groups, namely children, working mothers and the elderly.
The thesis presents three in-depth case studies within a framework of time geography. Each study highlights the individual mobility problems confronted by the selected transport-disadvantaged group. The first case study is a detailed investigation of children’s mobility to access educational opportunities. The next chapter examines gendered mobility of working mothers and their counterparts. Finally, a walkability study is carried out to evaluate how the walking environment affects outdoor mobility of the aging population. This research employs a suite of methods in evaluating individual mobility. Children’s access to educational opportunities is examined through the computation of the size of potential path area and the number of weighted opportunities reachable within given space-time constraints. To move on, multilevel analysis is carried out to compare the daily activity spaces of married couples. Finally, a walkability assessment is conducted to evaluate factors affecting older people’s access to health-care facilities. These approaches build up to a comprehensive and holistic view to explore the issue of socially sustainable transport.
By providing a more focused picture on the transport problems faced by groups which run the risks of being excluded in the mainstream transport development, this study has the potential to provide a new and comprehensive outlook in the theme of social sustainability in transport research. This thesis brings the social, spatial and temporal dimensions together in planning for a socially sustainable transport system. The results of each case study provide advice and develop initiatives to work towards a more inclusive, equitable and sustainable society. The findings from the chapter on children show that place disadvantage is an important issue to be addressed. For working mothers, the household responsibility hypothesis is evident, despite the compact city environment. The final chapter shows that active transport can benefit elderly citizens in a multitude of ways. More walkability assessments surrounding health-care and other opportunities should be looked into and audited. From the findings, the research concludes that the needs of these groups are not thoroughly addressed in Hong Kong, and related geographical research is also limited in the field. The urge to address the preferences and needs of these groups are of strategic
importance. Recommendations for future research include an improved understanding of the needs among an expanded range of stakeholders and depending on the locations in where they live.published_or_final_version
Geography
Doctoral
Doctor of Philosophy
4
Brockmann, Dirk, Vincent David, and Alejandro Morales Gallardo. "Human mobility and spatial disease dynamics." Universitätsbibliothek Leipzig, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-188611.
Full textAbstract:
The understanding of human mobility and the development of qualitative models as well as quantitative theories for it is
of key importance to the research of human infectious disease dynamics on large geographical scales. In our globalized world,
mobility and traffic have reached a complexity and volume of unprecedented degree. Long range human mobility is now
responsible for the rapid geographical spread of emergent infectious diseases. Multiscale human mobility networks exhibit two prominent features: (1) Networks exhibit a strong heterogeneity, the distribution of weights, traffic fluxes and populations sizes of communities range over many orders of magnitude. (2) Although the interaction magnitude in terms of traffic intensities decreases with distance, the observed power-laws indicate that long range interactions play a significant role in spatial disease dynamics. We will review how the topological features of traffic networks can be incorporated in models for disease dynamics and show, that the way topology is translated into dynamics can have a profound impact on the overall disease dynamics. We will also introduce a class of spatially extended models in which the impact and interplay of both spatial heterogeneity as well as long range spatial interactions can be investigated in a systematic fashion. Our analysis of multiscale human mobility networks is based on a proxy network of dispersing US dollar bills, which we incorporated in a model to produce real-time epidemic forecasts that projected the spatial spread of the recent outbreak of Influenza A(H1N1).
5
Voge, Tom. "Automated transport systems for sustainable urban mobility." Thesis, University of Southampton, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.485515.
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The thesis has as a general aim to analyse if and to what extent automated urban transport systems (AUTS) can provide more sustainable mobility in urban areas. AUTS is defined as a transport system with the following properties. AUTS consist of a fleet of road vehicles with fully automated driving capabilities for passenger transport on a network of roads with on-demand and door-to-door capability. The vehicle fleet is under control of a central management system in order to meet a particular demand in a particular environment. Key Findings are that various related systems and technologies which provide one or more of the functionalities of AUTS have proven to be feasible and to provide some of the benefits anticipated for AUTS. A number of early AUTS applications have already been used or tested since 1997; these systems have proven to be safe and reliable, but various perceived risks so far delayed a wider implementation. Users and stakeholders were able to envisage the potential of AUTS to improve urban mobility, but some concerns remained at this stage over technology being mature enough for systems in mixed traffic. After having used the system, public acceptance increased, as due to the innovative characteristics of AUTS, users who had no direct experience with the system before, developed a different attitude. AUTS vehicle performance parameters including acceleration, deceleration, and jerk are below benchmark values for comparable systems in terms of comfort and safety levels for passengers. AUTS as part of the multi-modal public transport system and with accompanying measures can improve .network efficiency and reduce travel times. The research has shown that there is large potential for AUTS to provide more sustainable mobility in urban areas. But a number of implementation barriers have been identified, which so far have hindered a more widespread and large-scale implementation of AUTS. Future work in this field therefore has to address these issues and to develop means to overcome these barriers in order to realise the potentials of AUTS. Furthermore sensor technologies and robotics algorithms have to be further improved, and new vehicle, infrastructure and operational concepts have to be developed for larger and more advanced systems.
6
Brockmann, Dirk, Vincent David, and Alejandro Morales Gallardo. "Human mobility and spatial disease dynamics." Diffusion fundamentals 11 (2009) 2, S. 1-27, 2009. https://ul.qucosa.de/id/qucosa%3A13918.
Full textAbstract:
The understanding of human mobility and the development of qualitative models as well as quantitative theories for it is
of key importance to the research of human infectious disease dynamics on large geographical scales. In our globalized world,
mobility and traffic have reached a complexity and volume of unprecedented degree. Long range human mobility is now
responsible for the rapid geographical spread of emergent infectious diseases. Multiscale human mobility networks exhibit two prominent features: (1) Networks exhibit a strong heterogeneity, the distribution of weights, traffic fluxes and populations sizes of communities range over many orders of magnitude. (2) Although the interaction magnitude in terms of traffic intensities decreases with distance, the observed power-laws indicate that long range interactions play a significant role in spatial disease dynamics. We will review how the topological features of traffic networks can be incorporated in models for disease dynamics and show, that the way topology is translated into dynamics can have a profound impact on the overall disease dynamics. We will also introduce a class of spatially extended models in which the impact and interplay of both spatial heterogeneity as well as long range spatial interactions can be investigated in a systematic fashion. Our analysis of multiscale human mobility networks is based on a proxy network of dispersing US dollar bills, which we incorporated in a model to produce real-time epidemic forecasts that projected the spatial spread of the recent outbreak of Influenza A(H1N1).
7
Hwang, T. K. Phillip. "Enhancing the mobility of the ageing population through human-powered mobility design." Thesis, Birmingham City University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298899.
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Granlund, Nilsson Mattias. "Artisan : Professional urban mobility." Thesis, Umeå universitet, Designhögskolan vid Umeå universitet, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-160366.
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The idea for this project initially came from an article i read about a small company in Stockholm, called “The cycling plumber” In the article, the founder of the company who explained that he was tired of looking for parking and sitting in traffic in his work-van around the tight and congest- ed streets of Stockholm. This sparked an interest from me, what options does the urban-operating handyman have in terms of transportation? Using the design process and thorough user studies, this project explores a new type of commercial vehicle segement, intended for carpenters operating in the dense city traffic of the future. The final product proposed, is called VW Artisan. It’s a versatile commercial vehicle utilizing a detachable toolbox system to improve the efficiency and comfort of the user during their daily work.Idén till detta projekt kom ursprungligen från en artikel som handlade om ett nytt företag i Stockholm, kallat “Cyklande rörmokaren”. I artikeln förklarade grundaren till företaget att han hade tröttnat på att sitta i köer och leta efter parkering runt Stockholms tätt trafikerade gator. Detta väckte ett intresse för mig. Vilka transportalternativ har en hantverkare som huvudsakligen arbetar i större städer? Med hjälp av designprocessen och utförliga användarstudier utforskar detta projektet en ny typ av kommersiellt fordonssegment, avsett för hantverkare i framtidens tätt befolkade städer. Slutresultatet som föreslås i detta projekt kallas för VW Artisan. Ett mångsidigt arbetsfordon med en avtagbar verktygsvagn för att effektivisera och öka komforten i användarens dagliga arbete.
9
Boud, John Michael. "The electron mobility in indium phosphide." Thesis, University of Surrey, 1988. http://epubs.surrey.ac.uk/847279/.
Full textAbstract:
Hall effect and resistivity measurements have been carried out as a function of hydrostatic pressure and temperature on a number of samples of indium phosphide ranging from exceptionally pure to highly doped. In the case of pure and lightly doped InP an iterative solution of the Boltzmann Equation has been used successfully to describe the temperature and pressure dependence of mobility over the helium temperature range. Measurements on the highest mobility samples of InP ever grown suggest that the conduction band deformation potential is 6. 7eV. For the case of highly doped material it was found that a theory of scattering from a correlated distribution of impurities describes both the temperature and pressure dependence of mobility well. Pressure dependent mobility measurements on a sample having an impurity density close to the Mott transition suggest that the inclusion of impurity band conduction in the analysis is necessary even at nitrogen temperatures and above. Such an analysis is used successfully to describe the temperature and pressure dependence of both mobility and Hall carrier concentration.
10
au, Knebworth@iinet net, and Iain Cameron. "Understanding, modelling and predicting transport mobility in urban environments." Murdoch University, 2004. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20050513.141512.
Full textAbstract:
In the last three decades the global population has been growing at an essentially constant rate, at around 1.5 per cent per year, to about 6.026 billion in 2000 when it was estimated that 47% of that population live in an urban environment. Further, a United Nations projection indicates that 60% of the total global population may be living in an urban settlement by the year 2025. This increasing urbanisation brings with it increased employment, that delivers affluence, which then continues the cycle of migration and movement to these growing metropolitan areas in both developed and developing countries.
As cities increase in population and expand their urban area, there is a consequential expansion of urban transportation and accompanying service infrastructure. People travel daily, irrespective of their vast differences in culture, economic conditions and means of transportation. This daily mobility is sought for its own sake as well as to bridge the spatial distance that separates their homes from the work place, to accomplish their households domestic needs and to undertake social journeys, such as visiting friends and taking holidays.
As the worlds urban population undertakes its daily mobility by a variety of transportation modes, an individuals mobility behaviour and mode-choice is governed by a complex matrix of physical and human, social and management indicators, measures and/or drivers. A literature review describes the current understanding of this complex matrix and concludes by identifying and defining a set of fundamental underlying measures that drive private motorised, public transport and non-motorised (walking and bicycling) mobility at national, city and household levels.
As practical instruments, transportation models play an important role in providing decision-makers with analytical tools to help them understand their citys transportation and the different future scenarios it may face. While not necessarily producing foolproof information or predictions, models are still the best methods available to test the likely implications of alternative transportation policy decisions in a rapidly changing urban environment. Urban transport models are generally based on the notion that traffic can be modelled in aggregate measures through statistical data and predictive modelling techniques.
In this research, dimensional analysis is used to derive sketch-plan models for private motorised, public transport and non-motorised mobility for any urban environment based on four-decades of detailed land-use and travel pattern data from a large international sample of cities. These models are developed on the basis of a set of fundamental underlying measures that are deemed to drive private motorised, public transport and non-motorised (walking and bicycling) mobility at the city level.
Importantly, the models also embody three key attributes. They are:
easy to use, minimising user requirements and data inputs
policy-sensitive, capable of assessing a sufficient range of policy options
reliable and robust over time, so that the results can be consistently believed.
The capacity of the sketch-plan models to predict personal mobility in an urban environment is statistically validated against an independent land-use and travel pattern data set for 83 cities located on five continents. Despite their simplicity and maintaining a consistent functional form over a time-series of four-decades and across all geographic and cultural regions, the private motorised mobility model can consistently explain up to 92% of the variance in private motorised urban mobility. The results for the public transport mobility model are less reliable and consistent, in particular when developing cities are part of the model. Results for developed or wealthier cities are much better. Reasons for these results and their inadequacies are discussed. The non-motorised modes mobility model is the least successful part of the modelling work. This can be attributed to a combination of inadequate data and, very likely, the more micro-level determinants of usage of these modes.
The private motorised urban mobility sketch-plan model equation developed in this thesis is able to predict present and future trends of automobile use in individual cities to a high degree of statistical reliability. The model equation offers urban transport planners a focused direction on the fundamental measures that have the potential to control and deliver automobile restraint policies and strategies. A series of case studies shows that this model has wide applications in understanding past trends in private motorised mobility and in developing urban environmental strategy and policy through its ability to calculate and assess current and future motor vehicle emissions inventories in cities. The thesis makes suggestions for future work in this area of metropolitan level transport modelling, in particular, how to improve the public and non-motorised transport models so that total urban transport mobility can be better understood and modelled.
11
Oberc, Barbara. "Gender and Mobility - Sustainable Development in the Transport Sector." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-236169.
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Several statistical studies show that women in developed countries, taken to be facing equal opportunities, are more environmentally benevolent in transport choice than men, as well as shape more environmentally benign (i.e. smaller) mobilities. Some researchers contend that a greater inclusion of women is needed in matters furthering sustainable development within the transport sector, because they believe women to be intrinsically more environmentally conscious. However, few qualitative studies explore the actual reasons behind women's more environmentally sustainable behavior in the transport sector. This qualitative study, conducted in Uppsala, aims to uncover the situation in present-day Sweden, a country renowned for its high level of sustainability and gender equality initiatives. Fourteen in-depth interviews were carried out (allowing for greater insight into the factors informing individuals' transport choices and mobility patterns) with a sample of individuals pertaining to two demographically different neighborhoods (providing an observation of the influence that other demographic and socio-economic factors might have). While the results show certain gendered undertones in the organization of the interviewed individuals' lifestyles, the reasons behind making certain transport choices and shaping one's mobility are reported by the study's subjects to be the same for both men and women. The primary factors guiding the interviewees' choices are predominantly linked to convenience, saving money, and saving time. Although the interviewees speak of facing equal opportunities, however, these appear to be to an extent still influenced by gender, mainly in the meaning ascribed to automobility and an unequal division of labor.
12
Thomas, Kalarikad Jonah. "Transport properties of high mobility one-dimensional electron gases." Thesis, University of Cambridge, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.627346.
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Sadeghian, Paria. "Human mobility behavior : Transport mode detection by GPS data." Licentiate thesis, Högskolan Dalarna, Institutionen för information och teknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:du-36346.
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GPS tracking data are widely used to understand human travel behavior and to evaluate the impact of travel. A major advantage with the usage of GPS tracking devices for collecting data is that it enables the researcher to collect large amounts of highly accurate and detailed human mobility data. However, unlabeled GPS tracking data does not easily lend itself to detecting transportation mode and this has given rise to a range of methods and algorithms for this purpose. The algorithms used vary in design and functionality, from defining specific rules to advanced machine learning algorithms. There is however no previous comprehensive review of these algorithms and this thesis aims to identify their essential features and methods and to develop and demonstrate a method for the detection of transport mode in GPS tracking data. To do this, it is necessary to have a detailed description of the particular journey undertaken by an individual. Therefore, as part of the investigation, a microdata analytic approach is applied to the problem areas, including the stages of data collection, data processing, analyzing the data, and decision making. In order to fill the research gap, Paper I consists of a systematic literature review of the methods and essential features used for detecting the transport mode in unlabeled GPS tracking data. Selected empirical studies were categorized into rule-based methods, statistical methods, and machine learning methods. The evaluation shows that machine learning algorithms are the most common. In the evaluation, I compared the methods previously used, extracted features, types of dataset, and model accuracy of transport mode detection. The results show that there is no standard method used in transport mode detection. In the light of these results, I propose in Paper II a stepwise methodology to detect five transport modes taking advantage of the unlabeled GPS data by first using an unsupervised algorithm to detect the five transport modes. A GIS multi-criteria process was applied to label part of the dataset. The performance of the five supervised algorithms was evaluated by applying them to different portions of the labeled dataset. The results show that stepwise methodology can achieve high accuracy in detecting the transport mode by labeling only 10% of the data from the entire dataset. For the future, one interesting area to explore would be the application of the stepwise methodology to a balanced and larger dataset. A semi-supervised deep-learning approach is suggested for development in transport mode detection, since this method can detect transport modes with only small amounts of labeled data. Thus, the stepwise methodology can be improved upon for further studies.
14
Nazari, zahra. "New Paradigm of Mobility, Public Transport, and Sharing Economy." Thesis, Malmö universitet, Fakulteten för kultur och samhälle (KS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-21300.
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Abstract This study aims to contribute to getting more knowledge about how promoting and strengthening the new paradigm of mobility in a deprived area led to social inclusion. The advent of women's transport on a global scale is only a sign of greater gender inequality in cities being manifested by their limited access to urban resources. Integrating a theoretical framework of mobility justice and social justice with the methodological praxis of focus group, semi-structured interview, and statistics that the research has been conducted an in-depth interview with 9 participating women which are subsequently implemented through feminist research. The analytical part of the study is illustrated within three critical considerations of gendered daily mobilities: temporal, spatial, and those relating to wider concerns of policy and transport planning. Ultimately, the research suggests that the new paradigm of mobility expands the sharing mobility opportunities of women in the district, and a step towards reducing wider inequity in public health in form of increasing knowledge alliance and culture of learning.
15
Cameron, Iain. "Understanding, modelling and predicting transport mobility in urban environments." Thesis, Cameron, Iain (2004) Understanding, modelling and predicting transport mobility in urban environments. PhD thesis, Murdoch University, 2004. https://researchrepository.murdoch.edu.au/id/eprint/499/.
Full textAbstract:
In the last three decades the global population has been growing at an essentially constant rate, at around 1.5 per cent per year, to about 6.026 billion in 2000 when it was estimated that 47% of that population live in an urban environment. Further, a United Nations' projection indicates that 60% of the total global population may be living in an urban settlement by the year 2025. This increasing urbanisation brings with it increased employment, that delivers affluence, which then continues the cycle of migration and movement to these growing metropolitan areas in both developed and developing countries.
As cities increase in population and expand their urban area, there is a consequential expansion of urban transportation and accompanying service infrastructure. People travel daily, irrespective of their vast differences in culture, economic conditions and means of transportation. This daily mobility is sought for its own sake as well as to bridge the spatial distance that separates their homes from the work place, to accomplish their household's domestic needs and to undertake social journeys, such as visiting friends and taking holidays.
As the world's urban population undertakes its daily mobility by a variety of transportation modes, an individual's mobility behaviour and mode-choice is governed by a complex matrix of physical and human, social and management indicators, measures and/or drivers. A literature review describes the current understanding of this complex matrix and concludes by identifying and defining a set of fundamental underlying measures that drive private motorised, public transport and non-motorised (walking and bicycling) mobility at national, city and household levels.
As practical instruments, transportation models play an important role in providing decision-makers with analytical tools to help them understand their city's transportation and the different future scenarios it may face. While not necessarily producing foolproof information or predictions, models are still the best methods available to test the likely implications of alternative transportation policy decisions in a rapidly changing urban environment. Urban transport models are generally based on the notion that traffic can be modelled in aggregate measures through statistical data and predictive modelling techniques.
In this research, dimensional analysis is used to derive sketch-plan models for private motorised, public transport and non-motorised mobility for any urban environment based on four-decades of detailed land-use and travel pattern data from a large international sample of cities. These models are developed on the basis of a set of fundamental underlying measures that are deemed to drive private motorised, public transport and non-motorised (walking and bicycling) mobility at the city level.
Importantly, the models also embody three key attributes. They are:
* easy to use, minimising user requirements and data inputs
* policy-sensitive, capable of assessing a sufficient range of policy options
* reliable and robust over time, so that the results can be consistently believed.
The capacity of the sketch-plan models to predict personal mobility in an urban environment is statistically validated against an independent land-use and travel pattern data set for 83 cities located on five continents. Despite their simplicity and maintaining a consistent functional form over a time-series of four-decades and across all geographic and cultural regions, the private motorised mobility model can consistently explain up to 92% of the variance in private motorised urban mobility. The results for the public transport mobility model are less reliable and consistent, in particular when developing cities are part of the model. Results for developed or wealthier cities are much better. Reasons for these results and their inadequacies are discussed. The non-motorised modes mobility model is the least successful part of the modelling work. This can be attributed to a combination of inadequate data and, very likely, the more micro-level determinants of usage of these modes.
The private motorised urban mobility sketch-plan model equation developed in this thesis is able to predict present and future trends of automobile use in individual cities to a high degree of statistical reliability. The model equation offers urban transport planners a focused direction on the fundamental measures that have the potential to control and deliver automobile restraint policies and strategies. A series of case studies shows that this model has wide applications in understanding past trends in private motorised mobility and in developing urban environmental strategy and policy through its ability to calculate and assess current and future motor vehicle emissions inventories in cities. The thesis makes suggestions for future work in this area of metropolitan level transport modelling, in particular, how to improve the public and non-motorised transport models so that total urban transport mobility can be better understood and modelled.
16
Cameron, Iain. "Understanding, modelling and predicting transport mobility in urban environments." Cameron, Iain (2004) Understanding, modelling and predicting transport mobility in urban environments. PhD thesis, Murdoch University, 2004. http://researchrepository.murdoch.edu.au/499/.
Full textAbstract:
In the last three decades the global population has been growing at an essentially constant rate, at around 1.5 per cent per year, to about 6.026 billion in 2000 when it was estimated that 47% of that population live in an urban environment. Further, a United Nations' projection indicates that 60% of the total global population may be living in an urban settlement by the year 2025. This increasing urbanisation brings with it increased employment, that delivers affluence, which then continues the cycle of migration and movement to these growing metropolitan areas in both developed and developing countries.
As cities increase in population and expand their urban area, there is a consequential expansion of urban transportation and accompanying service infrastructure. People travel daily, irrespective of their vast differences in culture, economic conditions and means of transportation. This daily mobility is sought for its own sake as well as to bridge the spatial distance that separates their homes from the work place, to accomplish their household's domestic needs and to undertake social journeys, such as visiting friends and taking holidays.
As the world's urban population undertakes its daily mobility by a variety of transportation modes, an individual's mobility behaviour and mode-choice is governed by a complex matrix of physical and human, social and management indicators, measures and/or drivers. A literature review describes the current understanding of this complex matrix and concludes by identifying and defining a set of fundamental underlying measures that drive private motorised, public transport and non-motorised (walking and bicycling) mobility at national, city and household levels.
As practical instruments, transportation models play an important role in providing decision-makers with analytical tools to help them understand their city's transportation and the different future scenarios it may face. While not necessarily producing foolproof information or predictions, models are still the best methods available to test the likely implications of alternative transportation policy decisions in a rapidly changing urban environment. Urban transport models are generally based on the notion that traffic can be modelled in aggregate measures through statistical data and predictive modelling techniques.
In this research, dimensional analysis is used to derive sketch-plan models for private motorised, public transport and non-motorised mobility for any urban environment based on four-decades of detailed land-use and travel pattern data from a large international sample of cities. These models are developed on the basis of a set of fundamental underlying measures that are deemed to drive private motorised, public transport and non-motorised (walking and bicycling) mobility at the city level.
Importantly, the models also embody three key attributes. They are:
* easy to use, minimising user requirements and data inputs
* policy-sensitive, capable of assessing a sufficient range of policy options
* reliable and robust over time, so that the results can be consistently believed.
The capacity of the sketch-plan models to predict personal mobility in an urban environment is statistically validated against an independent land-use and travel pattern data set for 83 cities located on five continents. Despite their simplicity and maintaining a consistent functional form over a time-series of four-decades and across all geographic and cultural regions, the private motorised mobility model can consistently explain up to 92% of the variance in private motorised urban mobility. The results for the public transport mobility model are less reliable and consistent, in particular when developing cities are part of the model. Results for developed or wealthier cities are much better. Reasons for these results and their inadequacies are discussed. The non-motorised modes mobility model is the least successful part of the modelling work. This can be attributed to a combination of inadequate data and, very likely, the more micro-level determinants of usage of these modes.
The private motorised urban mobility sketch-plan model equation developed in this thesis is able to predict present and future trends of automobile use in individual cities to a high degree of statistical reliability. The model equation offers urban transport planners a focused direction on the fundamental measures that have the potential to control and deliver automobile restraint policies and strategies. A series of case studies shows that this model has wide applications in understanding past trends in private motorised mobility and in developing urban environmental strategy and policy through its ability to calculate and assess current and future motor vehicle emissions inventories in cities. The thesis makes suggestions for future work in this area of metropolitan level transport modelling, in particular, how to improve the public and non-motorised transport models so that total urban transport mobility can be better understood and modelled.
17
Bendiksen, Bård A., Eddy W. Hansen, and Harald Walderhaug. "NMR studies of benzene mobility in metal-organic framework UiO-67." Universitätsbibliothek Leipzig, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-182918.
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Wright, K. T. "Electrical transport calculations for off-axis silicon." Thesis, Cardiff University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.373877.
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Bejoy, B. J., and B. Paramasivan. "RELIABILITY ORIENTED TRANSPORT PROTOCOL IN WSN." IJCSN Journal, 2012. http://hdl.handle.net/10150/229012.
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Wireless Sensor Network consists of tens or thousands of
sensor nodes scattered in a physical space and one or
more Base stations or Sinks. Even thought developed for
military applications now they find a wide variety of
civilian applications also. Some of the applications are
Target tracking, Animal monitoring, Vehicle monitoring.
The need (or lack thereof) for reliability in a sensor
network is firmly dependent upon the specific
application the sensor network is used for. Some
applications like re-tasking or reprogramming sensor
nodes [upgrading software or algorithms, adding codes,
scripts etc] over -the-air requires assured delivery of
high-priority events to sinks. We believe that as the
number of sensor network applications grows, there will
be a need to build more powerful general-purpose
hardware and software environments capable of
reprogramming or retasking sensors to.Wireless sensor network is a special form of wireless networks dedicated to surveillance and monitoring applications Reliability in wireless sensor network is application specific. The specific form of reliability might change from application to application. Our idea is to generate reliability based transport protocol that is customizable to meet the needs of emerging reliable data applications in sensor networks and is also adaptive when the nodes are mobile. In our approach, clusters are formed for minimizing energy dissipation. The nodes maintain a neighbor list to forward data and any changes in the local topology can trigger updates to a node’s neighbor list. If a node notices that its neighbor list has changed, it can spontaneously re-advertise all of its data thus providing reliable transport in mobility conditions also. Our approach has five phases-setup, relaying, relay initiated error recovery, selective status reporting and node supervising. Our simulation results prove that the proposed approach can outperform existing related techniques and is highly responsive to the various error and mobility conditions experienced in sensor networks.
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Harrison, Ian. "A study of colloidal mobility in glacial sand formation." Thesis, Nottingham Trent University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.309568.
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Jakobsson, Mattias. "Monte Carlo Studies of Charge Transport Below the Mobility Edge." Doctoral thesis, Linköpings universitet, Beräkningsfysik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-74322.
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Charge transport below the mobility edge, where the charge carriers are hopping between localized electronic states, is the dominant charge transport mechanism in a wide range of disordered materials. This type of incoherent charge transport is fundamentally different from the coherent charge transport in ordered crystalline materials. With the advent of organic electronics, where small organic molecules or polymers replace traditional inorganic semiconductors, the interest for this type of hopping charge transport has increased greatly. The work documented in this thesis has been dedicated to the understanding of this charge transport below the mobility edge. While analytical solutions exist for the transport coefficients in several simplified models of hopping charge transport, no analytical solutions yet exist that can describe these coefficients in most real systems. Due to this, Monte Carlo simulations, sometimes described as ideal experiments performed by computers, have been extensively used in this work. A particularly interesting organic system is deoxyribonucleic acid (DNA). Besides its overwhelming biological importance, DNA’s recognition and self-assembly properties have made it an interesting candidate as a molecular wire in the field of molecular electronics. In this work, it is shown that incoherent hopping and the Nobel prize-awarded Marcus theory can be used to describe the results of experimental studies on DNA. Furthermore, using this experimentally verified model, predictions of the bottlenecks in DNA conduction are made. The second part of this work concerns charge transport in conjugated polymers, the flagship of organic materials with respect to processability. It is shown that polaronic effects, accounted for by Marcus theory but not by the more commonly used Miller-Abrahams theory, can be very important for the charge transport process. A significant step is also taken in the modeling of the off-diagonal disorder in organic systems. By taking the geometry of the system from large-scale molecular dynamics simulations and calculating the electronic transfer integrals using Mulliken theory, the off-diagonal disorder is for the first time modeled directly from theory without the need for an assumed parametric random distribution.
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Adanu, Emmanuel Kofi. "Exploratory Applications of Epidemiological Methods in Transport Safety and Mobility." Thesis, The University of Alabama, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10603643.
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Evident similarities and links between the outcomes of traffic crashes and stranded (or constrained) mobility have been identified and are reported in this research. Generally, a high level of travel activities is an indicator of high crash exposure. However, studies have shown that the highest rates of traffic fatalities occur in low- and middle-income regions, where many citizens experience relatively low levels of motorized travel. This ironic observation reveals serious challenges facing transport mobility systems in the less privileged regions of the world. Studies on traffic crashes and mobility constraints also reveal that they both have individual and regional variations in their occurrence, effects, and severities. Consequently, the outcomes of traffic crashes and constrained mobility are serious public health concerns worldwide.
As public health problems, their study is analogous to the study of diseases and other injuries and thus, suitable for the application of epidemiological techniques. This dissertation therefore explores the use of epidemiological techniques to analyze traffic crashes and mobility/accessibility constraints from a human-centered perspective. The dissertation therefore consists of two major focus areas. The first part of the study applies widely used epidemiology/public health – based statistical tools to analyze traffic crashes with the aim of gaining better understanding of the human-centered causes and factors that influence these causes, and how these ultimately affect the severity of crashes. This part is further divided into two sub-sections. The first sub-section used latent class analysis to identify homogeneous clusters of human-centered crash causal factors and then applied latent class logit and random parameters logit modeling techniques to investigate the effects of these factors on crash outcomes. The second sub-section of the first part of the dissertation applies multilevel regression analysis to understand the effects of driver residential factors on driver behaviors in an attempt to explain the area-based differences in the severity of road crashes across sub-regions. Both studies are necessary to develop potential human-centered mitigations and interventions and for the effective and targeted implementation of those countermeasures. The second part of the study provides an epidemiological framework for addressing mobility/accessibility constraints with a view to diagnosing symptoms, recommending treatment, and even discussing the idea of transmission of constrained mobility among city dwellers. The medical condition, hypomobility, has been used to connote constrained mobility and accessibility for people in urban areas. In transportation and urban studies, hypomobility can result in a diminished ability to engage in economic opportunities and social activities, hence deepening poverty and social exclusion and increasing transport costs, among other negative outcomes. The condition is especially pronounced in poor urban areas in developing countries. The framework proposed in this study is expected to help identify and address barriers to mobility and accessibility in the rapidly growing cities throughout the developing world, with particular applicability to the rapidly developing cities in Sub-Saharan Africa.
Ultimately, this dissertation explores the application of epidemiological techniques to two major transportation problems: traffic safety and constrained mobility. The techniques presented in this dissertation provide policy makers, agencies, and transport professionals with tools for evidence-based policies and effective implementation of appropriate countermeasures.
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Falkmer, Torbjörn. "Transport mobility for children and adolescents with cerebral palsy (CP) /." Linköping : Univ, 2001. http://www.bibl.liu.se/liupubl/disp/disp2001/med672s.pdf.
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Meneau, Aurélie Yvette Béatrice. "Charge transport physics of high-mobility, solution-crystallised molecular semiconductors." Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708741.
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Fletcher, Marc Philipp. "Insulated gating and electrical transport of InGaAs high mobility devices." Thesis, University of Cambridge, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648821.
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Gupta, Adbhut. "Hydrodynamic and ballistic transport in high-mobility GaAs/AlGaAs heterostructures." Diss., Virginia Tech, 2021. http://hdl.handle.net/10919/105062.
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The understanding and study of electron transport in semiconductor systems has been the instigation behind the growth of semiconductor electronics industry which has enabled technological developments that are part of our everyday lives. However, most materials exhibit diffusive electron transport where electrons scatter off disorder (impurities, phonons, defects, etc.) inevitably present in the system, and lose their momentum. Advances in material science have led to the discovery of materials which are essentially disorder-free and exhibit exceptionally high mobilities, enabling transport physics beyond diffusive transport. In this work, we explore non-diffusive transport regimes, namely, the ballistic and hydrodynamic regimes in a high-mobility two-dimensional electron system in a GaAs quantum well in a GaAs/AlGaAs heterostructure. The hydrodynamic regime exhibits collective fluid-like behavior of electrons which leads to the formation of current vortices, attributable to the dominance of electron-electron interactions in this regime. The ballistic regime occurs at low temperatures, where electron-electron interactions are weak, constraining the electrons to scatter predominantly against the device boundaries.
To study these non-diffusive regimes, we fabricate mesoscopic devices with multiple point contacts on the heterostructure, and perform variable-temperature (4.1 K to 40 K) zero-field nonlocal resistance measurements at various locations in the device to map the movement of electrons. The experiments, along with interpretation using kinetic simulations, demarcate hydrodynamic and ballistic regimes and establish the dominant role of electron-electron interactions in the hydrodynamic regime. To further understand the role of electron-electron interactions, we perform nonlocal resistance measurements in the presence of magnetic field in transverse magnetic focusing geometries under variable temperature (0.39 K to 36 K). Using our experimental results and insights from the kinetic simulations, we quantify electron-electron scattering length, while also highlighting the importance of electron-electron interactions even in ballistic transport. At a more fundamental level, we reveal the presence of current vortices in both hydrodynamic and surprisingly, ballistic regimes both in the presence and absence of magnetic field. We demonstrate that even the ballistic regime can manifest negative nonlocal resistances which should not be considered as the hallmark signature of hydrodynamic regime. The work sheds a new light on both hydrodynamic and ballistic transport in high-mobility solid-state systems, highlighting the similarities between these non-diffusive regimes and at the same time providing a way of effectively demarcating them using innovative device design, measurement schemes and one-to-one modeling. The similarities stem from total electron system momentum conservation in both the hydrodynamic and ballistic regimes. The work also presents a sensitive and precise experimental technique for measuring electron-electron scattering length, which is a fundamental quantity in solid-state physics.Doctor of Philosophy
Electrons are the charged particles that are bound around the nuclei of atoms. But sometimes in a solid material electrons break free away from the nuclei and wander around. They are then the carriers of electric current ubiquitous in our daily lives as in our homes, and in our electronic devices such as smartphones and computers. Often an analogy is made between the flow of electric current in a material and the flow of water in a stream. However, the analogy does not hold well for most materials. In most materials the motion of electrons can be thought of as balls in a pinball machine - their movement hindered and randomized by collisions with the countless defects and impurities present in the material they travel through. However, recently scientists have been able to synthesize ultraclean materials, where electrons can indeed mimic the flow of water under the right conditions. In this aptly-named hydrodynamic regime, electrons predominantly interact with each other and that leads to the formation of current whirlpools or vortices similar to those forming in water. A telling signature of this regime is a negative electrical resistance appearing near the location of the vortex. When the interactions between electrons are weak, such as at very low temperatures, electrons move along straight-line trajectories until they hit and bounce off the device edges, similar to billiard balls. This low-temperature phenomenon is called ballistic transport. In this work we reveal that measurement of negative resistance and formation of current vortices are not unique to the hydrodynamic regime but can occur in the ballistic regime as well. It is indeed counterintuitive that electrons moving like billiards balls can behave similarly to electrons flowing like water. The similarities can be traced back to a fundamental physics conservation law active in both situations, namely momentum conservation. To experimentally realize the tests, we use a very high purity semiconductor material GaAs/AlGaAs and fabricate tiny devices on the material with a cutting-edge design, capable of precisely measuring resistance at various locations along the device to map the movement of electrons. The simulations of the novel physics indeed reveal current vortices of various sizes in the ballistic regime, in agreement with the experimental data showing negative resistance. In another experiment, we apply a magnetic field, making the electrons move in circular paths. If uninterrupted, electrons complete half circles and are collected through an opening in the device, giving resistance peaks in experiments. Due to electron-electron interactions, the electrons on their circular trajectory are interrupted by other electrons which leads to a decay in resistance peaks. This decay is utilized to measure the strength of electron-electron interactions. The work has both fundamental and applied implications. The existence of whirlpools shows that the electron momentum is not lost by collisions, and that in turn means that the conduction of electrical current in these regimes is inherently efficient. This opens up avenues for electronic devices which are faster, more functional and more power efficient than present electronic devices.
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Bachir, Danya. "Estimating urban mobility with mobile network geolocation data mining." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLL004/document.
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Dans les prochaines décennies, la circulation et les temps de trajets augmenteront drastiquement en raison du fort taux d'accroissement de la population urbaine. L'augmentation grandissante de la congestion sur les réseaux de transports menace le bon fonctionnement des villes à plusieurs niveaux, tels que le bien-être des citoyens, la santé, l'économie, le tourisme ou la pollution.Ainsi, il est urgent, pour les autorités locales et nationales, de promouvoir l'innovation pour la planification urbaine, à l'aide d'une politique de soutien à l'innovation et de prises de mesures radicales.Pour guider les processus de décisions, il est crucial d'estimer, analyser et comprendre la mobilité urbaine au quotidien.Traditionnellement, les informations sur les déplacements des populations était collectées via des rapports nationaux et locaux, tels que les recensements et les enquêtes. Toutefois, ces derniers ont un coût important, induisant une très faible fréquence de mise-à-jour, ainsi qu'une temporalité restreinte des données.En parallèle, les technologies de l'information et de la communication fournissent une quantité de données de mobilité sans précédent, au jour le jour, toutes catégories de population confondues. En particulier, les téléphones portables accompagnent désormais la majorité des citoyens lors de leurs déplacements et activités du quotidien. Dans cette thèse, nous estimons la mobilité urbaine par l'exploration des données du réseau mobile, qui sont collectées en temps réel, sans coût additionnel, par les opérateurs télécoms. Le traitement des données brutes est non-trivial en raison de leur nature sporadique et de la faible précision spatiale couplée à un bruit complexe.La thèse adresse deux problématiques via un schéma d'apprentissage faiblement supervisé (i.e., utilisant très peu de données labellisées) combinant plusieurs sources de données de mobilité. Dans un premier temps, nous estimons les densités de population et le nombre de visiteurs au cours du temps, à une échelle spatio-temporelle relativement fine.Dans un second temps, nous construisons les matrices Origine-Destination qui représentent les flux totaux de déplacements au cours du temps, pour différents modes de transports.Ces estimations sont validées par une comparaison avec des données de mobilité externes, avec lesquelles de fortes corrélations et de faibles erreurs sont obtenues.Les modèles proposés sont robustes au bruit et à la faible fréquence des données, bien que la performance des modèles soit fortement dépendante de l'échelle spatiale.Pour atteindre une performance optimale, la calibration des modèles doit également prendre en compte la zone d'étude et le mode de transport. Cette étape est nécessaire pour réduire les biais générés par une densité urbaine hétérogène et les différents comportements utilisateur.Ces travaux sont les premiers à estimer les flux totaux de voyageurs routiers et ferrés dans le temps, à l'échelle intra-régionale.Bien qu'une validation plus approfondie des modèles soit requise pour les renforcer, nos résultats mettent en évidence l'énorme potentiel de la science des données de réseaux mobiles appliquées à la planification urbaineIn the upcoming decades, traffic and travel times are expected to skyrocket, following tremendous population growth in urban territories. The increasing congestion on transport networks threatens cities efficiency at several levels such as citizens well-being, health, economy, tourism and pollution. Thus, local and national authorities are urged to promote urban planning innovation by adopting supportive policies leading to effective and radical measures. Prior to decision making processes, it is crucial to estimate, analyze and understand daily urban mobility. Traditionally, the information on population movements has been gathered through national and local reports such as census and surveys. Still, such materials are constrained by their important cost, inducing extremely low-update frequency and lack of temporal variability. On the meantime, information and communications technologies are providing an unprecedented quantity of up-to-date mobility data, across all categories of population. In particular, most individuals carry their mobile phone everywhere through their daily trips and activities. In this thesis, we estimate urban mobility by mining mobile network data, which are collected in real-time by mobile phone providers at no extra-cost. Processing the raw data is non-trivial as one must deal with temporal sparsity, coarse spatial precision and complex spatial noise. The thesis addresses two problematics through a weakly supervised learning scheme (i.e., using few labeled data) combining several mobility data sources. First, we estimate population densities and number of visitors over time, at fine spatio-temporal resolutions. Second, we derive Origin-Destination matrices representing total travel flows over time, per transport modes. All estimates are exhaustively validated against external mobility data, with high correlations and small errors. Overall, the proposed models are robust to noise and sparse data yet the performance highly depends on the choice of the spatial resolution. In addition, reaching optimal model performance requires extra-calibration specific to the case study region and to the transportation mode. This step is necessary to account for the bias induced by the joined effect of heterogeneous urban density and user behavior. Our work is the first successful attempt to characterize total road and rail passenger flows over time, at the intra-region level.Although additional in-depth validation is required to strengthen this statement, our findings highlight the huge potential of mobile network data mining for urban planning applications
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Hussen, Berhanu Woldetensae. "Sustaining Sustainable Mobility : the Integration of Multimodal Public Transportation in Addis Ababa." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSE2042/document.
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Addis-Abeba, qui s’étend sur 540 km2 et compte 3,1 millions d’habitants, connait aujourd’hui des transformations socio-économiques et spatiales rapides. Elle n’est pas seulement le coeur politique, commercial, économique et financier du pays mais aussi une ville internationale accueillant le siège de l’Union africaine et d’autres institutions internationales. Comme d’autres villes africaines, elle connait un rythme élevé d’urbanisation. Ce processus a impliqué la croissance du nombre d’habitants mais aussi une extension spatiale accrue. En conséquence, la demande de déplacements et la longueur des parcours ont augmenté. Le transport joue ainsi un rôle clé, pesant sur le développement socio-économique et la configuration de l’espace urbain. Tout aussi important, en tant que demande dérivée, il joue sur la capacité des citadins à accomplir leurs diverses activités. La motorisation des ménages restant faible en dépit d’une lente progression, le transport public constitue le principal moyen d’accès à une mobilité motorisée pour la majorité de la population. L’offre est constituée d’une multitude d’opérateurs formels et informels, travaillant selon un schéma artisanal. On estime à plus de 18 000 les véhicules de transport public, la plupart de faible capacité, qui parcourent chaque jour les rues d’Addis-Abeba. En dépit de son importance, le transport public souffre de capacités d’investissement insuffisantes ainsi que, jusqu’à récemment, du manque d’une politique publique claire et affirmée. Il pâtit également de l’absence d’une approche intégrée, pour sa planification, sa gestion et sa mise en oeuvre. De nombreuses villes du Nord, parfois depuis près d’un demi-siècle, ont choisi de construire un service intégré de transport public. L’intégration y est vue comme un outil viable pour offrir un transport urbain de haute qualité et « sans couture », permettant un développement urbain durable. Par contre, les villes africaines, caractérisées par une urbanisation rapide, des taux d’équipement automobile faibles, un système de transport public déficient et des contraintes financières majeures manquent de telles expériences d’intégration du transport public. Notre question est donc : « Comment les villes africaines peuvent-elles reproduire et mettre en oeuvre des politiques d’intégration du transport public ? », originellement développées dans les villes du Nord. La thèse essaie d’apporter des éléments de réponse à cette question. Elle s’appuie sur une analyse des différentes formes d’intégration du transport public. Puis elle propose un schéma de conception et de mise en oeuvre d’un système de transport public intégré, appréhendé comme un outil de mobilité urbaine durable pour Addis-AbebaAddis Ababa, with an area of 540 km2 and with population of 3.1 million people is experiencing a rapid pace of socio-economic and physical transformation. The city is not only the political, commercial, economic and financial hub of the country but also an international city serving as the seat of the African Union and various international organizations. Alike many African Cities, Addis Ababa has been undergoing a high rate of urbanization. This process of rapid urbanization has resulted in the increase in the size of the population and the physical expansion of the city. As a consequence, travel demand and length of the trip are increasing. Transportation plays a key role in determining the socioeconomic development and shaping the spatial development framework of the city. Equally important, transportation as derived demand is also a fundamental means for residents to fulfill their various activities. In Addis Ababa motorization, although on the increase, is low and public transportation is the most important mode of motorized mobility for the large majority of the city’s population. There are various formal and informal operators of the public transport mainly operating on individual basis. It is estimated that there are over 18,000 public transport vehicles that are daily running in Addis Ababa, most of them low capacity vehicles. Despite its importance, the public transport sector not only suffers from shortage, insufficient capital investment, and until recently lack of clear governmental policy and leadership but also from the absence of integrated approach to its operation, planning and management.Many cities in the North have embarked on integrating the provision of public transportation for nearly half a century now. In these cities, integration in public transportation has been recommended as a viable instrument for providing high quality and seamless urban transport and enhancing sustainable urban development. African cities which are characterized by their high urbanization rate, low level of private car ownership, deficient public transportation system and significant financial constraints lack public transportation integration experiences. The question is then ‘how do African cities replicate and implement public transport integration practices?’ that have been originally developed for the Cities of the North. The thesis attempts to answer this question and analyses the different forms of public transport integration. It then proposes a framework for implementing integrated public transport as a sustainable means of urban mobility in Addis Ababa
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Mahamat, Hemchi Hassane. "Mobilités urbaines et planification : le cas de N'Djamena." Thesis, Bordeaux 3, 2015. http://www.theses.fr/2015BOR30011/document.
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Le rapport de l’individu à son environnement urbain, déjà complexe, se complexifie aujourd’hui davantage du fait de la prolifération de nouvelles pratiques de mobilité. De nouveaux espaces urbains sont créés, appuyés par des politiques, des cultures et des moyens. Pour s'en persuader, il suffit de rappeler que l'aptitude à se mouvoir est une faculté essentielle de tout individu, une condition de survie de toutes les sociétés qui détermine le degré de développement du territoire. Notre étude s'attache à montrer comment chaque type d'acteur concerné conçoit et organise les rapports entre mobilité et territoire. Nous étudions comment les différentes stratégies s'inscrivent dans l'espace urbain et nous aident à mieux appréhender ses atouts et ses limites et comment se pratiquent les mobilités urbaines. Nous proposons des grilles de lecture de ces dernières à partir du cas de la ville de N’Djamena, la capitale tchadienne. Cette étude traite de la mobilité urbaine à partir de l’analyse du fonctionnement actuel du système de transport ainsi que des stratégies de gestion urbaine et d’adaptation aux mobilités par la population de N’Djamena. Différentes stratégies sont mises en œuvre aussi bien par la population que par les opérateurs de transports qui sont souvent des particuliers travaillant en collaboration avec les différents syndicats. Pour prendre en considération les différents aspects et enjeux socio-spatiaux des pratiques des mobilités urbaines à travers la ville de N’Djamena, il s’est révélé pertinent et heuristique de croiser les différents outils et disciplines que constituent l’urbanisme, la sociologie, la géographie et l’ingénierie des transports. L'espace n'est jamais donné, il est toujours construit. Ce travail tente ainsi de définir dans un premier temps les différents concepts en lien avec les mobilités urbaines tantôt confondus, souvent antagonistes, leurs origines et leurs interprétations. Nous démontrons que la mobilité se présente comme un concept soulevant des enjeux d’ordre social, urbanistique, économique, géographique, etc. Dans un second temps, ce travail analyse les modalités d’adaptation de la population face aux offres de transports que propose le secteur dans des conditions d’insuffisance accrue à travers toute la ville de N’Djamena en termes de planification, de gestion et de moyen de transport. C’est ainsi que cette étude aborde les dysfonctionnements du système des transports de la capitale tchadienne ainsi que les stratégies d’adaptation de la population, en particulier celles de la périphérie que représentent le 1er, le 8e et le 9e arrondissement. Cette étude analyse ainsi les origines et les causes de la prolifération du système des transports que sont les mototaxis. Ces derniers, apparus dans les années soixante-dix, constituent aujourd’hui une pratique qui évolue entre acceptation citoyenne et refus politiqueThe relation of the individual to his urban environment, already complex, is more complex today because of the proliferation of new mobility practices. New urban spaces are created, supported by policies, cultures and resources.To be convinced of it, we need to remember that the ability to move is an essential right of any individual, a condition of survival of all societies which determines the degree of development of the territory. Our study attempts to show how each type of actor concerned designs and organizes the link between mobility and territory. We study how different strategies are part of the urban space and help us to better understand its strengths and limitations, and how to practice urban mobility. We offer reading grids of the latterbased on the case of the city of N'Djamena, the capital of Chad.This study deals with urban mobility from the analysis of the current transport system functioning, as well as urban management and adaptation strategies tomobilities by the population of N'Djamena. Different strategies are implemented both by the population and by transport operators who are often individuals working in collaboration with various unions. To consider the various socio-spatial aspects and issues of urban mobility practices through the city of N'Djamena, it has been relevant and heuristic to cross the different tools and disciplines of urban planning, sociology, geography and transportation engineering. Space is never given, it is always built. This work thus attempts to define at first the various concepts related to urban mobility – sometimes confused, often antagonistic –, their origins and their interpretations. We demonstrate that mobility is as a concept rising social, urban planning, economic and geographical issues, amongst others. Secondly, this work analyzes the modalities of adaptation of the population to transport offers, in a context of increasing deficiencyconditions in planning, management and conveyancethroughout the city of N'Djamena. Thus, this study addresses the shortcomings of Chadian capital transport system as well as the adaptation strategies of the population, particularly within the periphery that is the 1st, 8th and 9th districts.This study analyzes the origins and causes of the proliferation of bikecabs within the transport system. The latter, appeared in the seventies, is today a practice that evolves between citizen acceptance and political refusal
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Nevrlá, Alice. "Uplatnění principů trvalé udržitelnosti v dopravě." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-226947.
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This master’s thesis summarizes the sustainable transport issues and practical applications in this field. It also deals with components of non-sustainable transport, European Union's policy and explores the theory of externalities in sustainable transport. On a practical example - parking in the Brno city center, is finding a solution to the problem of insufficient parking capacity, using principles of sustainable transport
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Pivano, Cyril. "Désagrégation spatiale des données de mobilité du recensement de la population appliquée à l'Ile-de-France." Thesis, Paris Est, 2016. http://www.theses.fr/2016PESC1185/document.
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Bendiksen, Bård A., Eddy W. Hansen, and Harald Walderhaug. "NMR studies of benzene mobility in metal-organic framework UiO-67." Diffusion fundamentals 20 (2013) 43, S. 1, 2013. https://ul.qucosa.de/id/qucosa%3A13612.
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Bonneville, Jean-Baptiste. "Quel modèle économique pour une offre de transport de voyageurs porte-à-porte ?" Thesis, Paris Est, 2018. http://www.theses.fr/2018PESC1007/document.
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Fournir un service de mobilité porte-à-porte pour les voyageurs est un objectif largement partagé. C’est aussi un objectif stratégique pour SNCF. En effet, après plus de trente années de croissance portée par le TGV, l’entreprise a fait face à des difficultés qui l’ont incitée à revoir son modèle économique. Elle vise à s’affirmer comme un véritable opérateur multimodal et à retrouver, grâce à d’autres modes que le train, sa vocation de desserte fine des territoires. Le porte-à-porte consiste à permettre aux individus d’aller d’une origine à une destination sans utiliser leur voiture, donc en utilisant différents moyens de transport mis bout à bout. La question posée est celle de l’existence d’un hypothétique opérateur de mobilité porte-à-porte qui serait l’interlocuteur unique du voyageur et qui lui garantirait la continuité de service tout au long du déplacement. Ce travail étudie, dans une démarche de recherche-intervention, les modèles économiques possibles pour un opérateur de mobilité porte-à-porte : quelle offre, quelle organisation entre les acteurs, quelle répartition des coûts et de la valeur ? La thèse apporte dans un premier temps une analyse approfondie de la notion de porte-à-porte pour les voyageurs. Ensuite elle détaille les enjeux pour les différentes parties prenantes. Les évolutions du contexte réglementaire de la mobilité en France, les enjeux relatifs au développement durable et la modification des équilibres en place sous l’effet de la transition numérique de l’économie sont passés en revue. Au sein de SNCF, différents approches du porte-à-porte existent qui reflètent la complexité de l’entreprise. L’évolution du système d’acteurs dans leur diversité ouvre des perspectives nouvelles. Trois grands types de modèles économiques pour le porte-à-porte sont identifiés : un modèle intégré, un modèle de plate-forme et un modèle distribué. Il en découle des trajectoires possibles de moyen et long termes pour le groupe ferroviaire. Sans être exclusifs les uns des autres, les trois modèles ont chacun leur domaine de pertinence. Affirmer un modèle économique distribué du porte-à-porte semble toutefois être une orientation à privilégier pour que le transport ferroviaire reste pertinent face à la voiture individuelleThe goal of providing passengers with seamless door-to-door mobility has today become a common objective, and a key priority for SNCF, France’s historical national rail group. After more than 30 years of growth thanks to the success of the TGV high-speed train, SNCF faces difficulties that have prompted it to reconsider its business model. The firm has decided to become a genuine multimodal operator with the capacity to provide a comprehensive territorial service through a variety of transport modes. The principal function of door-to-door transport is to enable travellers to go from A to B without using their own cars but a sequence of transport modes. This raises the possibility of the emergence of door-to-door mobility operators that provide a one-stop shop for travellers and offer continuity of service provision over an entire journey. This paper explores possible business models for a door-to-door mobility operator: the nature of the service, organisation between stakeholders and the revenue model. It begins with a detailed analysis of the idea of door-to-door service in the context of passenger transport. It then studies the main challenges for the stakeholders, in particular the evolution of France’s regulatory framework, issues relating to sustainable development and the effects of the digital economy. Different approaches to door-to-door provision exist within SNCF, reflecting the complexity of the company. Growing diversity in the system of actors has opened up new possibilities. Three contrasting business models were identified for door-to-door services: the integrated model, the platform model and the distributed model, all of which offer possible mid-term and long-term strategic directions for SNCF. Without being mutually exclusive, all three models are relevant in their distinct spheres. Nevertheless, the distributed model would seem to offer the greatest potential for rail transport to remain competitive with the private car
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Roland, Ulf, Khanneh W. Fomba, Frank Stallmach, Petrik Galvosas, Jörg Kärger, and Frank-Dieter Kopinke. "Influence of phase transitions on the mobility of organic pollutants in synthetic and natural polymers." Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-197022.
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Wootton, Gayle. "Inclusive urban mobility : participation, rights and decision-making in transport planning." Thesis, Cardiff University, 2018. http://orca.cf.ac.uk/116529/.
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The aim of this research is to combine theories of public participation and rights-based approaches to governance with discourses on social exclusion and transport disadvantage explored through a case study of a planned mass public transport system in a city adopting a rights-based approach to participatory governance. It does so by using a mixed-method case study approach, utilising qualitative research methods. Quito in Ecuador provided the natural choice for the case study given its rights-based approach to participatory governance determined through the Constitution of 2008 and the Law of Citizen Participation (2010), and shortly after receiving the devolved responsibility for urban planning and transport, the city government took the decision to install a metro line in the city centre. The research addressed three research questions. First, it examined the extent to which transport related social exclusion is intensified by existing practices of transport planning and operation. Second, it looked at the potential benefit of a rights-based approach to participatory governance. Third, it examined how a conceptualised understanding of transport-related social exclusion was able to describe the phenomenon as it exists in Quito, and through a framework devised from the literature to evaluate participatory activities, it considered both the activities of the city government in engaging the public, alongside the response received from citizens and civil society organisations. The research concluded that a rights-based approaches to participation in decision-making can address transport-related social exclusion and mobility challenges. Although Quito’s metro project fell into the ‘prepare-reveal-defend’ model of decision making, there were genuine attempts by the city government to initiate participation. Some initiatives took place after the decision was made, and others were overly complex i.e. the formulaic process of the ‘Offering of Accounts’. The research also determined that cultural change is required for residents to embrace a new open government, and that civil society organisations have a key role to play on fostering better participatory processes, and ultimately decision-making.
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Golbuff, Laura. "Moving beyond physical mobility : blogging about cycling and urban transport policy." Thesis, Cardiff University, 2014. http://orca.cf.ac.uk/73196/.
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It is often acknowledged that movement exists in multiple, interdependent forms and that we live in an Information Age. However, mobilities perspectives on contemporary cycling tend to neglect the a) interconnections between transport (physical mobility of people and objects) and communication (mobility of symbolic information) b) paradigmatic shifts in modernity that affect how and why we communicate about transport. This thesis responds to such neglect. Firstly, it places urban cycling in an internet context by examining practices and perceptions of policy blogging, asking why do individuals blog about cycling-related transport policy and to what effect? Secondly, it analyses the answers to these questions through the theoretical lens of the risk society and reflexive modernisation theses. Empirical data is the result of 46 semi-structured interviews with bloggers and expert system representatives, mostly in London, New York and Paris. Blogging about cycling-related transport policy is shown to be an individualised response to the perceived failings of expert systems, as well as in Giddens’ words, a ‘reflexive project of the self’. Citizens who may otherwise only be policy subjects or passive consumers of transport, emerge as policy, media and civil society actors by virtue of their ability to publish information, which forms the basis of social relations. Through blogging, they produce and mobilise knowledge. Knowledge claims mediated by blogging interact with expert systems responsible for transport, which in turn adapt; routine institutional practices evolve; a new order emerges; blogging makes a difference. That difference is however limited, not least because the public remains reliant on expert systems. Ultimately, despite the obvious importance of physical mobility to cycling, this thesis seeks to move beyond it. Information and communication technologies have radically altered how we - researchers, the public, expert system representatives - communicate about and understand cycling, and as such, this project argues for a renewed emphasis on mobilities in a genuinely plural sense of the word as being about more than physically moving from A to B.
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Yadav, Meeta. "Design of a Transport Layer Protocol for 4G Wireless Systems, Mobility." NCSU, 2003. http://www.lib.ncsu.edu/theses/available/etd-06162003-162847/unrestricted/etd.pdf.
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El, Rashidy Rawia Ahmed Hassan. "The resilience of road transport networks : redundancy, vulnerability and mobility characteristics." Thesis, University of Leeds, 2014. http://etheses.whiterose.ac.uk/7782/.
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This thesis is concerned with the development of a composite resilience index for road transport networks. The index employs three characteristics, namely redundancy, vulnerability and mobility, measuring resilience at network junction, link and origin-destination levels, respectively. Various techniques have been adopted to quantify each characteristic and the composite resilience index as summarised below. The redundancy indicator for road transport network junctions is based on the entropy concept, due to its ability to measure the system configuration in addition to being able to model the inherent uncertainty in road transport network conditions. Various system parameters based on different combinations of link flow, relative link spare capacity and relative link speed were examined. The developed redundancy indicator covers the static aspect of redundancy, i.e. alternative paths, and the dynamic feature of redundancy reflected by the availability of spare capacity under different network loading and service level. The vulnerability indicator for road transport network links is developed by combining vulnerability attributes (e.g. link capacity, flow, length, free flow and traffic congestion density) with different weights using a new methodology based on fuzzy logic and exhaustive search optimisation techniques. Furthermore, the network vulnerability indicators are calculated using two different aggregations: an aggregated vulnerability indicator based on physical characteristics and the other based on operational characteristics. The mobility indicator for road transport networks is formulated from two mobility attributes reflecting the physical connectivity and level of service. The combination of the two mobility attributes into a single mobility indicator is achieved by a fuzzy logic approach. Finally, the interdependence of the proposed characteristics is explored and the composite resilience index is estimated from the aggregation of the three characteristics indicators using two different approaches, namely equal weighting and principal component analysis methods. Moreover, the impact of real-time travel information on the proposed resilience characteristics and the composite resilience index has been investigated. The application of the proposed methodology on a synthetic road transport network of Delft city (Netherlands) and other real life case studies shows that the developed indicators for the three characteristics and the composite resilience index responded well to traffic load change and supply variations. The developed composite resilience index will be of use in various ways; first, helping decision makers in understanding the dynamic nature of resilience under different disruptive events, highlighting weaknesses in the network and future planning to mitigate the impact of disruptive events. Furthermore, each developed indicator for the three characteristics considered can be used as a tool to assess the effectiveness of different management policies or technologies to improve the overall network performance or the daily operation of road transport networks.
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Yuill, Brendan Thomas. "Sediment Transport and Bed Mobility in a Low-ordered Ephemeral Watershed." Diss., The University of Arizona, 2009. http://hdl.handle.net/10150/195269.
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This dissertation reports the results of a field based study examining sediment transport and bed mobility in a low-ordered, ephemeral watershed. Runoff and sediment transport concentrations were sampled at the watershed outlet to determine flow discharge and sediment flux during approximately 21 flow events, from 1998 - 2007. Sediment collected in flow was measured for grain-size distribution to determine if specific grain-size fractions behave differently while in transport. The coarse sediment yield was measured for mass and grain-size distribution at the watershed outlet for two years, 2005 - 2006. Further, the arrangement and composition of the channel bed material was comprehensively mapped using terrestrial-based photogrammetry for the years, 2005 - 2006. Results show that patterns of sediment transport are complex, controlled in part by flow hydraulics but also by other phenomena. Some of the variation in sediment transport is determined by grain-size. Grain-sizes with different sources within the watershed and that transported by different transport modes were observed to follow different patterns of transport. Also, the channel bed, which serves as the source for the coarse fraction of the sediment transport, was observed to change in grain composition during periods of flow. This tendency for the bed material to evolve in time likely affected the amount and composition of the sediment grains that were entrained from it.An additional objective of this dissertation was to determine how unique the observed patterns of sediment transport were to low-order ephemeral channels. Sediment transport and yield were modeled using bed load transport formulae designed to capture the physical mechanics of transport as observed in perennial streams. Results show that contemporary transport models predict transport within the field site with similar accuracy as that in many perennial systems but not well enough to rely on their predictions for many engineering applications.
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Cranois, Aude. "De l'automobilité à l'électromobilité : des conservatismes en mouvement ? : la fabrique d'une politique publique rurale entre innovations et résistances." Thesis, Paris Est, 2017. http://www.theses.fr/2017PESC1066/document.
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Les sociétés rurales sont caractérisées par des modes de vie et de déplacement quotidiens particulièrement dépendants du mode automobile, et la mobilité est, depuis longtemps déjà, un enjeu central des politiques publiques qui leur sont destinées. Les collectivités rurales sont prises dans une tension entre l'injonction à adopter des mobilités plus diversifiées, plus économes, et, en même temps, un climat d'incertitudes et des contraintes politiques et budgétaires qui freinent les choix de rupture. La thèse analyse les conditions d'émergence d'une offre de publique en faveur de l'électromobilité alors qu’une multitude de dispositifs encouragent l'introduction de voitures électriques, de vélos à assistance électrique et de bornes de recharge. Les acteurs ruraux s'en saisissent-ils pour autant ? Et de quelle manière ? La recherche questionne donc les modalités particulières du saisissement des instruments d’incitation liés à l’électromobilité dans les petites collectivités rurales et étudie la manière dont celles-ci acceptent, en la reformulant, cette injonction à la modernité et au changement. L'hypothèse centrale de cette thèse est que l'émergence de l'offre électromobile dans le monde rural fait l'objet d'une construction et d'une mise en forme conjointe, mais loin d'être consensuelle, entre le monde local (usagers, élus, opérateurs privés) et les acteurs extérieurs. En mobilisant une approche pluridisciplinaire, le déploiement très progressif de l’électromobilité est analysé dans le cadre d'une démarche de recherche menée dans la Manche et en Aveyron. Après une contextualisation de l’émergence des politiques électromobiles dans les deux territoires étudiés, la thèse montre comment ce nouveau champ de l'action publique permet aux élus ruraux d'adopter avec prudence et sans renier l'automobilité auxquels ils restent attachés, un nouveau référentiel de mobilité durable. L’électromobilité est une proposition saisie ou détournée, discutée et expérimentée avant d'être éventuellement intégrée à une stratégie territoriale en fonction des ressources et du rôle de l’acteur local. Ensuite, après avoir constaté la très grande diversité des thématiques qui introduisent l'offre politique de l’électromobilité dans les territoires ruraux, la thèse propose une typologie pour mieux comprendre le foisonnement de micro-projets électromobiles et les visées auxquelles est censé répondre du point de vue des élus. L’appropriation de l’électromobilité est engagée via une pragmatique locale par des acteurs à la recherche d’un nouveau modèle d’aménagement rural. Nous montrons, à travers quelques projets de plus grande envergure visant à déployer des bornes de recherche ou des véhicules à hydrogène, que le déploiement électromobile est aussi un objet de pouvoir. Dans deux départements marqués historiquement par la production électrique (l'une d'origine nucléaire, l'autre hydroélectrique) et donc par les proximités historiques de l'industriel et du monde politique local, la thèse montre le saisissement stratégique de l’électromobilité par des acteurs locaux, comme les syndicats départementaux d’énergie. Il s’agit de promouvoir un nouveau modèle économico-énergétique territorial tout en maintenant les proximités politico-industrielles de toujours. L'un des principaux résultats est le constat de l'écart entre l'apparence d'intense renouvellement que relaient les discours et la mise en scène de l'offre politique et le saupoudrage presque anecdotique des projets réels. Ces démarches semblent porter les ferments d’une réinvention économique, territoriale et sociale du monde rural très ambiguë. D'un côté, l'électromobilité est utilisée au profit de stratégies de conservation de rapports de pouvoir, même si certaines formes d'appropriation de l'électromobilité reconfigurent discrètement les cadres de production des politiques publiques d'aménagement rural, débouchant sur une image de la transition mobilitaire rurale plurielle, sinon divergenteRenewed mobility policies have been developed since the mid-2000s in French rural areas, which are particularly car dependent. Local authorities have chosen to offer alternatives to automotive mobility. This thesis analyzes the emergence of public electric mobility policies, while national or European incentives encourage their development (cars, bicycles, charging stations). Do rural actors seize these incentives? And how? This study questions therefore the particular ways in which the incentive mechanisms related to electromobility in small rural communities are taken advantage of and how local authorities consent to this encouragement to change. The main hypothesis of this research is that the emergence of e-mobility in rural territories is elaborated and shaped by both local stakeholders and external actors, not always in consensual ways. With a multidisciplinary approach, we study the gradual deployment of e-mobility in two French territories, the Manche department and the Aveyron department. This study is based on the monitoring of several projects, and on interviews of local stakeholders.Our results show how e-mobility is used by local stakeholders to negotiate the turn toward a more sustainable rural transportation network and to reconsider the automobility system. It is seized, discussed, tested or rejected and might be integrated into a territorial strategy, depending on the resources and on the role of local actors.E-mobility is undertaken in several ways. First, it is implanted in a diversity of local public policies (tourism, social inclusion, environment), within smaller projects such as electric bike rental or electric car sharing system. It emerges through practical initiatives which stakeholders come up with in search of new mobility systems for the territory.Secondly, we show that e-mobility is a strategic tool, in larger projects (hydrogen, charging stations) in order to promote an energy system for the territory. In two territories historically shaped by electrical production (nuclear power and hydroelectric power), we demonstrate that e-mobility represents a powerful tool in the context of an energy transition, as it enables stakeholders to secure their role within these territories.The movement toward this innovation is made in the continuity of the rural and local policies, targetting isues such as tourism or local economy, and in connection with the national energy policies of energy transition. Finally, we hypothesize that these projects can also lead to discontinuities, to a reinvention of the rural, toward a new energy network, and new mobilities
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Täuber, Daniela, Mario Heidernätsch, Michael Bauer, Günter Radons, Jörg Schuster, and Christian von Borczyskowski. "Single molecule tracking of the molecular mobility in thinning liquid films on thermally grown SiO 2." Universitätsbibliothek Leipzig, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-191721.
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Diffusion coefficients obtained from weighted mean square displacements along probe molecule trajectories within ultrathin liquid TEHOS films show a correlation with film thickness. By studying cumulative distributions obtained with a time resolution of 20 ms,
we could show that the diffusion is heterogeneous within our liquid films which consist of a few molecular layers only.
We detected two components of the diffusion process, a slower and a faster one. Thinning of the film due to evaporation caused a slowdown of the whole diffusion process. But this resulted not from a slowdown in the two contributing components itself. Instead their relative contributions changed in favor for the slow component. We conclude that there is no pronounced difference in the diffusion coefficients attributed to the molecular layers 3 to 5 vertically above the substrate, but with the loss of upper layers along with the thinning process the concentration of probe molecules in the near surface region containing only one or two molecular layers is increased.
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Lukaszewski, Daniel. "Multipath transport for virtual private networks." Thesis, Monterey, California: Naval Postgraduate School, 2017. http://hdl.handle.net/10945/53013.
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Approved for public release; distribution is unlimitedVirtual Private Networks (VPNs) are designed to use the Transmission Control Protocol (TCP) or User Datagram Protocol (UDP) to establish secure communication tunnels over public Internet. Multipath TCP (MPTCP) extends TCP to allow data to be delivered over multiple network paths simultaneously. This thesis first builds a testbed and investigates the potential of using MPTCP tunnels to increase the goodput of VPN communications and support seamless mobility. Based on the empirical results and an analysis of the MPTCP design in Linux kernels, we further introduce a full-multipath kernel, implementing a basic Multipath UDP (MPUDP) protocol into an existing Linux MPTCP kernel.We demonstrate the MPUDP protocol provides performance improvements over single path UDP tunnels and in some cases MPTCP tunnels. The MPUDP kernel should be further developed to include more efficient scheduling algorithms and path managers to allow better performance and mobility benefits seen with MPTCP.
Outstanding Thesis
Lieutenant, United States Navy
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Zhang, Zhiyang. "Probing Transport of Ion Dense Electrolytes using Electrophoretic NMR." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/51966.
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Ion transport of electrolytes determines the performance of many electroactive devices, from fuel cells to batteries to soft mechanical actuators. This dissertation aims to address some fundamental issues regarding ion transport of ion dense electrolytes using electrophoretic NMR and NMR diffusometry.
I first describe the design and fabrication of the first instrumentation capable of reliable ENMR on highly ion-dense electrolytes such as ionic liquids and electrolytes for zinc-air batteries. I design a new electrophoretic NMR sample cell using parallel capillaries to investigate the electrophoretic mobilities of pure ionic liquids. It shows the first study of a highly ion-dense electrolyte with electrophoretic NMR. Then I employ NMR diffusometry and electrophoretic NMR to investigate ion association of pure ionic liquids.
Then I use electrophoretic NMR technique to investigate the electrophoretic mobilities of electrolytes for zinc-air batteries. For Zn2+ salt added dicyanamide (dca) based ionic liquids, I investigate the effects of Zn2+ salt on chemical shift of dca and ion motion. The combination of mobilities measurements and diffusion measurements provides some new insight of ion aggregation.
We explore ion transport of ionic liquids inside the ionic polymer Nafion as a function of hydration level. When ionic liquids diffuse inside ionic polymers, isolated anions diffuse faster (e 4X) than cations at high hydration whereas ion associations result in substantially faster cation diffusion (d 3X) at low hydration inside membranes, revealing prevalent anionic aggregates.
Finally, we compare diffusion activation energy measurements in a hydrated perfluorosulfonate ionomer and aqueous solutions of triflic acid, which provides insight into water transport dynamics on sub-nm lengthscales. And we explore the physical meaning of activation energy, characterizing local intermolecular interactions that occur on the pre-diffusional (~ 1 ps) timescale.Ph. D.
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Keblowski, Wojciech. "Moving past sustainable mobility towards a critical perspective on urban transport. A right to the city-inspired analysis of fare-free public transport." Doctoral thesis, Universite Libre de Bruxelles, 2018. https://dipot.ulb.ac.be/dspace/bitstream/2013/270011/4/KEBLOWSKI.pdf.
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Cette thèse de doctorat est consacrée aux politiques de transport public gratuit, à travers des données empiriques tirées d'une analyse géographique globale de la FFPT et de programmes particuliers de FFPT à Tallinn (Estonie), Aubagne (France) et Chengdu (Chine). Le travail empirique et les réflexions qui y sont menées résultent d’un intérêt pour les « alternatives » urbaines et d’une réflexion sur la façon dont les celles-ci pourraient être identifiées et étudiées dans le domaine de transports urbains. Reconnaissant la domination des perspectives dites « néoclassiques » et « durables » sur le transport urbain, la thèse propose de remettre en cause cette domination en intégrant une dimension explicitement urbaine dans l'analyse des politiques des transports. L'objectif principal de la recherche est donc de renforcer le lien entre les traditions critiques de la théorie urbaine et la géographie des transports en analysant et en démontrant comment les politiques des transports sont également des politiques urbaines. Elle développe ainsi un cadre inspiré du concept de « droit à la ville » d’Henri Lefebvre. Cela permet d'étudier comment les politiques de transports sont étayées par des questions de gouvernance, de coalitions et de régimes urbains ;quels intérêts et acteurs elle représentent ;comment elles sont au centre de l’entre-preneurialisme urbain ainsi que des résistances aux logiques entrepreneuriales ;quel rôle elle jouent dans la compétitivité territoriale ;comment elle peuvent être explorées à travers des questions liées à la participation des travailleurs et des citoyens, en soulignant le rôle de ses travailleurs et utilisateurs. Dans ce sens, le « droit à la ville » est proposé comme une grille d’analyse critique à travers laquelle la réalité des transports urbains peut être vue, analysée et, de manière volontairement normative, modifiée.Doctorat en Sciences
info:eu-repo/semantics/nonPublished
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Vasudevan, Vandana. "Mobilité et accessibilité spatiale des femmes en milieu urbain : capabilités et bien-être." Thesis, Université Grenoble Alpes (ComUE), 2019. http://www.theses.fr/2019GREAH013.
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Historiquement, les femmes ont été exclues du processus de planification de la ville en raison d'attitudes sociales et culturelles enracinées qui les limitaient à la sphère privée.La planification, l'architecture et l'ingénierie étant des professions à prédominance masculine, peu de femmes se sont exprimées au niveau des décideurs politiques en matière de construction de villes, une situation qui n'a pas radicalement changé, même aujourd'hui. La féminisation de la main-d'œuvre a entraîné une augmentation du nombre de femmes occupant l'espace public. Ce n'est que dans les années 1970 que les géographes féministes ont commencé à souligner que le modèle de mouvement des femmes dans la ville était notamment différente de celui des hommes. Ils ont fait les voyages plus courts et plus fréquents et ont formé une toile, tandis que les trajectoires des hommes sont en grande partie linéaires. Les femmes portaient des bébés et des sacs d'épicerie et poussaient des poussettes, en mouvement. Dans plusieurs pays, elles ont moins accès aux véhicules privés marchaient plus et utilisaient plus de transports publics que les hommes. Ces particularités ont été attribuées à deux facteurs :Premièrement, les femmes qui travaillent assument un «double charge» tant pour le travail que pour les tâches ménagères / familiales. La « pauvreté temporelle» qui en résulte a influé sur leur carrière professionnelle, car les femmes prennent des emplois plus près de chez elles afin que le temps de trajet puisse être raccourci. Par conséquent, les femmes se sont limitées à certains types de professions qui peuvent être exécutées sans menacer la gestion des affaires domestiques. En outre, la mobilité des femmes a été limitée en raison du risque de harcèlement sexuel dans les espaces publics.Les études qui ont mis au premier plan ces questions de mobilité de genre ont presque toujours été réalisées dans des contextes occidentaux. On sait très peu de choses sur la mobilité des travailleuses urbaines dans les pays asiatiques moins développés. De plus, le rôle et l'impact de la mobilité sur la vie des femmes n'ont pas été examinés dans la littérature existante. Cette étude utilise une approche qualitative pour contribuer à notre compréhension des expériences de la ville des femmes des villes qui se déplacent dans les espaces publics de la manière suivante :1)En utilisant l'approche par les capacités, l'étude examine les mobilités quotidiennes des femmes des villes et leur emploi du temps dans différentes activités effectuées au cours d'une journée de travail. Cela étant fait, il met l'accent sur la façon dont leur capacité de mobilité affecte d'autres capacités nécessaires au bien-être, telles que les capacités de loisirs, de santé et de relations personnel.2)L'étude met l'accent sur l'accessibilité et montre que, pourtant que la mobilité est vitale, elle n'est pas une condition suffisante pour améliorer la qualité de vie des personnes. L'amélioration de l'accessibilité spatiale, qui englobe la capacité d'atteindre une destination ainsi que la qualité du parcours, devrait être constitue un objectif plus important pour les décideurs3)Afin de rendre opérationnel l'approche par les capacités, une nouvelle technique visuelle appelée « Jeu de cartes » utilisant des cartes illustrées ont été créées pour obtenir des réponses sur les activités et états d'être (fonctionnements dans la terminologie de l'approche par les capacités) actuellement réalisés et souhaitée.4)Comme la recherche primaire a été faite dans trois villes à travers un pays développé et en développement-la France et l'Inde-il offre des informations précieuses sur les points communs dans la vie des mères qui travaillent, qui coupent à travers le binaire des pays développés et en développement.L'étude conclut que la capacité de mobilité et d'accessibilité spatiale n'est pas seulement vitale pour les femmes, mais qu'elle contribue également à la réalisation d'autres capacités nécessaires au bien-êtreHistorically, women have been kept out of the city planning process due to embedded social and cultural attitudes which restricted them to the private sphere. As planning, architecture and engineering were male dominated professions, few women had a voice at policy-making level of city building, a situation which has not altered drastically even today. With the feminization of the labour force, more women began to occupy the public space and use urban infrastructure.Yet,it was not until the 1970s that feminist geographers began to point out that women’s movement pattern in the city was distinctly different from that of men’s. Women made shorter, more frequent trips and ‘trip chained’ i.e. linking their work trips to trips made for household and family related needs. This was different from men’s trajectories which were largely linear. Women also carried babies and grocery bags and pushed strollers while on the move. They had less access to private vehicles, walked more and used more public transport than men did. These behaviours have over time changed in western societies but remain stubbornly in place in developing countries.Researchers observed that the peculiarities of women’s mobility was due to two factors . Firstly, despite being in the labour force in increasing numbers, women’s responsibilities at home did not change. Working women bore ‘double burden’ of both work and household/child care responsibilities. The resulting ‘time poverty’ impacted their professional careers as women have been found to take jobs closer to home so that commute time can be saved. Consequently, women have restricted themselves to certain types of occupations that can be performed without threatening the management of the home front. Additionally, women’s mobility was restricted spatially and temporally by the risk of sexual harassment in public spaces including in transit environments like buses and metro stations.The studies which brought these issues of gendered mobility to the forefront have almost always been done in western contexts. Very little is known about the mobility of urban working women in less developed countries of Asia. Further, the role and impact of mobility on women’s overall lives has not been examined in existing literature. This study uses a qualitative approach to enhance our understanding of urban women’s experiences of the city as they move through public spaces in the following ways :1)Using the capability approach, the study micro examines urban women’s daily mobilities and their time usage in different activities performed during a working day. Having done that, it focusses on how their capability for mobility affects other capabilities necessary for well being, such as the capabilities for leisure, for health and fitness or for nurturing valued relationships. Such an approach, of looking at women’s mobility through the lens of capabilities and its role in women’s overall lives is a hitherto unexplored perspective.2)The study puts the spotlight on accessibility, showing that while mobility is vital, it is an insufficient condition to improve people’s quality of life. What is more meaningful as a goal for policy makers is the improvement of spatial accessibility, which encompasses reachability and quality of the journey undertaken.3)In order to operationalize the capability approach, a new visual technique named ‘Game of Cards’ using picture cards was created to elicit responses about achieved and potential functionings.4)As the primary research was done in three cities across a developed and developing country-France and India- it offers valuable insights about the commonalities in the lives of working mothers, that cut across the binary of developed and developing countries.The study concludes that the capability for mobility and spatial accessibility is not only vital on its own for women but is also instrumental in the attainment of other capabilities necessary for well being
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Rynning, Maja karoline. "Towards a Zero-Emission Urban Mobility Urban design as a mitigation strategy, harmonizing insights from research and practice." Thesis, Toulouse, INSA, 2018. http://www.theses.fr/2018ISAT0020/document.
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La thèse étudie la façon dont le design urbain peut être une stratégie pour promouvoir les mobilités zéro émission, dans le cadre d’une mobilité quotidienne, telles que la marche, le vélo et les transports en commun. Ce travail explore les connaissances des praticiens du design urbain bâti, à savoir des urbanistes, des aménageurs, des architectes ainsi que des paysagistes, en tant qu’une source complémentaire s’ajoutant à celles issues de la recherché. Des enquêtes ont été menées en France et en Norvège. Les résultats ont été croisés avec la littérature scientifique ainsi qu’avec la littérature issue du design urbain. Un changement modal permanent requiert que l’utilisation de modes zéro émission soit à la fois une possibilité et un plaisir. L’influence du design urbain sur les choix modaux est particulièrement importante durant le voyage, lorsque l’usager se déplace à travers la ville et ses espaces publics. En particulier, les interactions avec l’environnement bâti, à l’échelle d’un quartier, influencent la manière dont la personne se souviendra de son déplacement. Ce souvenir impactera, dans un second temps, ses futurs choix modaux. Ces interactions sont d’autant plus importantes dans le cas de la marche et du vélo, ce qui impacte directement l’utilisation des transports en communThe doctoral thesis explores how urban design can be a mobility-mitigation strategy to promote the use of zero-emission modes such as walking, cycling, and public transport. What is the potential contribution of neighbourhood-scale built-environment interventions towards a sustainable modal shift? The work explores the experience-based knowledge of urban design practitioners (urban planners and designers, architects, landscape architects) as a source for new insights, complementary to those of research. A mixed-methods approach was employed in France and in Norway, consisting of workshops, interviews, and a survey. The results were crossed with findings from research and design literature, analyzed from an interdisciplinary, holistic perspective. The results show that achieving a permanent modal shift requires the use of zero-emission choices to be both possible and pleasurable. The influence of urban design is likely most significant during trips, when a person moves through a city and its public spaces. Interactions with the neighbourhood-scale built environment influences overall travel satisfaction, and the remembered trip experience matters for future modal choices. Modal choices are highly individual; people’s barriers for a zero-emission choice vary. Urban design interventions can help lower these, through bigger or smaller measures
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Yu, Tsung-Hsing. "Numerical studies of heterojunction transport and High Electron Mobility Transistor (HEMT) devices." Diss., Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/13035.
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Davis, Annabel. "Relationships between transport, mobility, sustainable livelihoods and social capital for poverty reduction." Thesis, University of Wolverhampton, 2004. http://hdl.handle.net/2436/92340.
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Ekelund, Åsa. "Metal mobility and transport from an oil-shale mine, Lake Nõmmejärv, Estonia." Thesis, Stockholms universitet, Institutionen för naturgeografi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-195364.
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Mining activities have a large impact on the environment, for example by the release of heavy metals from acid mine drainage and erosion of mine waste. North-eastern Estonia has the largest commercially exploited oil-shale deposit in the world. Waste from the mining processes have led to contamination of groundwater and streams polluted by phenols, oil products, sulphates and heavy metals. This thesis concerns the metal mobility from oil-shale mines in north-eastern Estonia, through water flow in the drainage system directed into Lake Nõmmejärv, which acts as a sedimentation basin for the mining water. A sediment core along with lake bottom surface samples were retrieved and analysed for heavy metals associated with mining. Water samples were collected and analysed for TOC. The sedimentary records show distinctively the change with the high inflow of water. The analysis of heavy metal content does not suggest a high impact on the environment, possibly because of a buffering effect by the limestone bedrock. The contents of heavy metals are somewhat elevated compared to background contents in Swedish lake sediments, but only cadmium and nickel levels are in the range that can be hazardous for the survival of organisms.
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El-Dorghamy, Ahmed. "Children's potential mobility and appropriation of transport options in an informal settlement." Doctoral thesis, Humboldt-Universität zu Berlin, 2018. http://dx.doi.org/10.18452/19549.
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Die vorliegende Arbeit untersucht die tatsächliche und potenzielle Mobilität von Kindern aus einer informellen Siedlungsstruktur in einer Megacity des globalen Südens am Fall Ezbet El-Hagganas im Großraum Kairos; die Entwicklung von Mobilitätsgewohnheiten in der Kindheitsphase und bezieht sich dabei nicht nur auf Kinder als Nutzer, sondern berücksichtigt zudem deren unmittelbares soziales Umfeld und den gesamtgesellschaftlichen Kontext.
Der theoretische Rahmen für die Untersuchung der Mobilität von Kindern basiert auf Icek Ajzens Theorie des geplanten Verhaltens sowie auf Vincent Kaufmanns Konzeptualisierung des Motilitätsbegriffes. Primärdaten wurden in einer Feldstudie und in Fokusgruppen erhoben. Die Ergebnisse deuteten auf eine hohe Prävalenz der unabhängigen Mobilität von Kindern (child independent mobility, CIM) auf deren am häufigsten zu bewältigenden Strecke (zur Schule) hin, zunächst durch nicht motorisierte Formen der Verkehrsteilnahme, aber weitgehend auch mit Hilfe von verschiedenen formellen wie informellen Nahverkehrsmitteln. Es wurden sozio-kulturelle und sozialpsychologische Einflussfaktoren seitens sowohl Kindern als auch ihren Eltern identifiziert, die die Verkehrsteilnahme von Kindern hemmen oder befördern können. Gleichermaßen wurden hemmende Faktoren untersucht. Die Akzeptanz des Radfahrens von Kindern wurde als Fallbeispiel für unerschlossenes Mobilitätspotenzial untersucht und deutet auf die Prävalenz sozialpsychologischer Faktoren hin, die Entscheidungsfaktoren rationaler und praktischer Natur entgegenstehen und die die Verkehrsmittelnutzung von Kindern mindern; hier benannt als Nutzungslücke (appropriation gap). Die Ergebnisse wurden schließlich in Zusammenhang mit dem Konzept der Verkehrsteilnahme gestellt und erlauben die Diskussion von Implikationen für die politische Ebene und für den Diskurs von Mobilität in benachteiligten Gruppen der Gesellschaft.This study investigates the nature of children's actual and potential mobility in a case study of an informal settlement in a megacity of a developing country; namely Ezbet El-Haggana in Greater Cairo and explores the nature of the childhood phase of developing mobility practices and habits, not only as enabled by children themselves as commuters, but also as enabled by parents and the surrounding community and society. A theoretical framework was constructed through which children's mobility is investigated. It is based on Icek Ajzen's Theory of Planned Behavior and Vincent Kaufmann's conceptualization of Motility. The data was primarily collected through a field survey and focus groups. Results indicated high prevalence of child independent mobility (CIM) in the most frequent trip (to school), not only through active transport but also largely through different formal and informal transport services available. There are socio-cultural and socio-psychological factors among both the parents and the children that constitute the appropriation of mobility options that cater to children, either enabling or inhibiting their mobility. Through the experiences of children's mobility, the acquired skills and adaptive attitudes by both children and parents enhance children's potential mobility compared to children in wealthier communities that may be granted less mobility rights or have less competences among other factors. Inhibiting factors were also investigated; the specific case of acceptance of cycling for children. This exemplified prevalence of socio-psychological factors that overshadow practical and rational aspects of choice; it is articulated here as an appropriation gap. Results were finally associated with the conceptualization of appropriation to discuss implications for policy and for the discourses of mobility in disadvantaged communities.