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Transit Oriented Development theoretical and practical framework represents an important tool for municipalities, private actors and citizens to enhance quality of life in urban contexts. Planning cities that encourage sustainable mobility patterns can contribute to aim at diversifying land use and making cities more accessible, safer and attractive for people. Handen has developed as a car-dependant area that is planned to growth its population and build more than 9000 new housing units by 2030 (Haninge Kommun, 2016). The TOD standard 3.0 was applied in the area around Handen pendeltåg station, to practically assess the TODness level of the area and provide recommendations to take into a consideration for future and current developments. Using the TOD standard in Handen can contribute to aim at a more sustainable growth pattern for both current and expected new citizens on the area. After implementing the evaluation system, it was found out that the best ranked variables were Compactness and Cycling. In contrast the variables that received the lowest scores were Walk, Densify, Connect, and Shift. Overall, Handen scored a Bronze level of TODness. Therefore, there are several actions that could be implemented on the study area in order to improve the TODness level. Specifically, Handen needs to diversify its land use, enhance the pedestrian network, encourage land mix use, decrease the space destined to cars and increase pedestrian connectivity, among others.

Among the low-power wireless technologies that have emerged in recent years, ultra-wideband (UWB) has successfully established itself as the reference for accurate ranging and localization, both outdoors and indoors. Due to its unprecedented performance, paired with relatively low energy consumption, UWB is going to play a central role in the next wave of location-based applications. As the trend of integration in smartphones continues, UWB is also expected to reach ordinary users, revolutionizing our lives the same way GPS and similar technologies have done. But the impact of UWB may not be limited to ranging and localization. Because of its considerable data rate, and its robustness to obstacles and interference, UWB communication may hold untapped potential for sensing and control applications. Nevertheless, several research questions still need to be answered to assess whether UWB can be adopted widely in the communication and localization landscapes. On one hand, the rapid evolution of UWB radios and the release of ever more efficient chips is a clear indication of the growing market for this technology. However, for it to become pervasive, full-fledged communication and localization systems must be developed and evaluated, tackling the shortcomings affecting current prototypes. UWB systems are typically single-hop networks designed for small areas, making them impractical for large-scale coverage. This limitation is found in communication and localization systems alike. Specifically for communication systems, energy-efficient multi-hop protocols are hitherto unexplored. As for localization systems, they rely on mains-powered anchors to circumvent the issue of energy consumption, in addition to only supporting small areas. Very few options are available for light, easy to deploy infrastructures using battery-powered anchors. Nonetheless, large-scale systems are required in common settings like industrial facilities and agricultural fields, but also office spaces and museums. The general goal of enabling UWB in spaces like these entails a number of issues. Large multi-hop infrastructures exacerbate the known limitations of small, single-hop, networks; notably, reliability and latency requirements clash with the need to reduce energy consumption. Finally, when device mobility is a factor, continuity of operations across the covered area is a challenge in itself. In this thesis, we design energy-efficient UWB systems for large-scale areas, supporting device mobility across multi-hop infrastructures. As our opening contribution, we study the unique interference rejection properties of the radio to inform our design. This analysis yields a number of findings on the impact of interference in communication and distance estimation, that are directly usable by developers to improve UWB solutions. These findings also suggest that concurrent transmissions in the same frequency channel are a practical option in UWB. While the overlapping of frames is typically avoided to prevent collisions, concurrent transmissions have counter-intuitively been used to provide highly reliable communication primitives for a variety of traffic patterns in narrowband radios. In our first effort to use concurrent transmissions in a full system, we introduce the UWB version of Glossy, a renowned protocol for efficient network-wide synchronization and data dissemination. Inspired by the success of concurrency-based protocols in narrowband, we then apply the same principles to define a novel data collection protocol, Weaver. Instead of relying on independent Glossy floods like state-of-the-art systems, we weave multiple data flows together to make our collection engine faster, more reliable and more energy-efficient. With Glossy and Weaver supporting the communication aspect in large-scale networks, we then propose techniques for large-scale localization systems. We introduce TALLA, a TDoA solution for continuous position estimation based on wireless synchronization. We evaluate TALLA in an UWB testbed and in simulations, for which we replicate accurately the behavior of the clocks in our real-world platforms. We then offer a glimpse of what TALLA can be employed for, deploying an infrastructure in a science museum to track visitors. The collected movement traces allow us to analyze fine-grained stop-move mobility patterns and infer the sequence of visited exhibits, which is only possible because of the high spatio-temporal granularity offered by TALLA. Finally, with SONAR, we tackle the issue of large-scale ranging and localization when the infrastructure cannot be mains-powered. By blending synchronization and scheduling operations into neighbor discovery and ranging, we drastically reduce energy consumption and ensure years-long system lifetime. Overall, this thesis enhances UWB applicability in scenarios that were previously precluded to the technology, by providing the missing communication and localization support for large areas and battery-powered devices. Throughout the thesis, we follow an experiment-driven approach to validate our protocol models and simulations. Based on the evidence collected during this research endeavor, we develop full systems that operate in a large testbed at our premises, showing that our solutions are immediately applicable in real settings.

<p>Within this thesis, we examined the possibilities of using an increasing amount of<br />publicly available metadata about locations and peoples&#39; activities in order to gain<br />new knowledge and develop new models of behavior and movement of people. The<br />purpose of the research conducted for this thesis was to solve practical problems,<br />such as: analyzing attractive tourist sites, defining the most frequent routes people<br />are taking, defining main ways of transportation, and discovering behavioral<br />patterns in terms of defining strategies to suppress expansion of virus infections. In<br />this thesis, a practical study was carried out on the basis of protected (aggregated<br />and anonymous) CDR (Caller Data Records) data and metadata of geo-referenced<br />multimedia content.</p> / <p>Предмет и циљ истраживања докторске дисертације представља евалуација<br />могућности коришћења све веће количине јавно доступних података о<br />локацији и кретању људи, како би се дошло до нових сазнања, развили нови<br />модели понашања и кретања људи који се могу применити за решавање<br />практичних проблема као што су: анализа атрактивних туристичких локација,<br />откривање путања кретања људи и средстава транспорта које најчешће<br />користе, као и откривање важних параметара на основу којих се може<br />развити стратегија за заштиту нације од инфективних болести итд. У раду је у<br />ту сврхе спроведена практична студија на бази заштићених (агрегираних и<br />анонимизираних) ЦДР података и метаподатака гео-референцираног<br />мултимедијалног садржаја. Приступ је заснован на примени техника<br />вештачке интелигенције и истраживања података.</p> / <p>Predmet i cilj istraživanja doktorske disertacije predstavlja evaluacija<br />mogućnosti korišćenja sve veće količine javno dostupnih podataka o<br />lokaciji i kretanju ljudi, kako bi se došlo do novih saznanja, razvili novi<br />modeli ponašanja i kretanja ljudi koji se mogu primeniti za rešavanje<br />praktičnih problema kao što su: analiza atraktivnih turističkih lokacija,<br />otkrivanje putanja kretanja ljudi i sredstava transporta koje najčešće<br />koriste, kao i otkrivanje važnih parametara na osnovu kojih se može<br />razviti strategija za zaštitu nacije od infektivnih bolesti itd. U radu je u<br />tu svrhe sprovedena praktična studija na bazi zaštićenih (agregiranih i<br />anonimiziranih) CDR podataka i metapodataka geo-referenciranog<br />multimedijalnog sadržaja. Pristup je zasnovan na primeni tehnika<br />veštačke inteligencije i istraživanja podataka.</p>

The continuous progression of urbanization has resulted in an increasing number of people living in cities or towns. In parallel, advancements in technologies, such as the Internet, telecommunications, and transportation, have allowed for better connectivity among people. This has engendered drastic changes in urban systems during the recent decades. From a social geographic perspective, the changes in urban systems are primarily characterized by intensive contacts among people and their interactions with the surrounding urban environment, which further leads to subsequent challenging problems such as traffic jams, environmental pollution, urban sprawl, etc. These problems have been reported to be heterogeneous and non-deterministic. Hence, to cope with them, massive amounts of geographic data are required to create new knowledge on urban systems. Due to the thriving of Volunteer Geographic Information (VGI) in recent years, this thesis presents knowledge on urban systems based on extensive VGI datasets from three sources: highway dataset from the OpenStreetMap (OSM) project, photo location dataset from the Flickr website, and GPS tracking datasets from volunteers, taxicabs, and air flights. The knowledge primarily relates to two issues of urban systems: the urban space and the corresponding human dynamics. In accordance, on one hand, urban space acts as a carrier for associated geographic activities and knowledge of it benefits our understanding of current social and economic problems in urban systems. On the other hand, human dynamics reflect human behavior in urban space, which leads to complex mobility or activity patterns. Its investigation allows a derivation of the underlying driving force that is very instructive to urban planning, traffic management, and infectious disease control. Therefore, to fully understand the two issues, this thesis conducts a thorough investigation from multiple aspects. The first issue is investigated from four aspects. First, at the city level, the controversial topic of city size regularity is investigated in terms of natural cities, and the conclusion is that Zipf’s law holds stably for all US cities. Second, at the sub-city level, the size distribution of spatial units within different cities in terms of the clusters formed by street nodes, photo locations, and taxi static points are explored, and the result shows a remarkable scaling property of these spatial units. Third, enlightened by the scaling property of the urban space at the city or sub-city level, this thesis devises a novel tool that can demarcate the cities into three categories: compact cities, normal cities, and sprawling cities. The tool is then applied to cities in both the US and three European countries. In the last, another representation of urban space is taken into account, namely the transportation network. The findings report that the US airport network displays the properties of scale-free, small-world, and disassortative mixing and that the individual natural airports show heterogeneous patterns that are probably subject to geographic constraints and socioeconomic factors. The second issue is examined from four perspectives. First, at the city level, the movement flow contributed by agents using two types of behavior is investigated through an agent-based simulation, and the result conjectures that the human mobility behavior is mainly shaped by the underlying street network. Second, at the country level, this thesis reports that the human travel length by air can be approximated well by an exponential distribution, and subsequent simulations indicate that human mobility behavior is largely constrained by the underlying airport network. Third, at the regional level, the length that humans travel by car is demonstrated to agree well with a power law with exponential cutoff distribution, and subsequent simulation further reproduces this levy flight characteristic. Based on the simulation, human mobility behavior is again revealed to be primarily shaped by the underlying hierarchical spatial structure. Finally, taxicab static points are adopted to explore human activity patterns, which can be characterized as the regularities in space and time, the heterogeneity and predictability in space. From a complex system perspective, this thesis presents the knowledge discovered in urban systems using massive volumes of geographic data. Together with new knowledge from empirical findings, the development of methods, and the design of theoretic models, this thesis also shares the research community with geographic data generated from extensive VGI datasets and the corresponding source codes. Moreover, this study is aligned with a paradigm shift in that it analyzes large-size datasets using high processing power as opposed to analyzing small-size datasets with low processing power. / <p>QC 20121113</p>