100 research outputs found

    Geographic Information Systems: A Tutorial and Introduction

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    his tutorial provides a foundation in GIS including its basic structure, concepts, and spatial analysis. GIS is a new field in business schools and presents opportunities for research. It is derived from about a dozen disciplines, some unfamiliar to most IS researchers. Following an overview of vertical-sector uses of GIS, the paper introduces their costs and benefits. The links of GIS to related technologies such as GPS, wireless, location-based technologies, web services, and RFID are examined. Conceptual models and research methodologies are discussed, including Spatial Decision Support Systems (SDSS), and GIS in visualization, organizational studies, and end user computing. Suggestions for future research are presented

    Capturing time in space : Dynamic analysis of accessibility and mobility to support spatial planning with open data and tools

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    Understanding the spatial patterns of accessibility and mobility are a key (factor) to comprehend the functioning of our societies. Hence, their analysis has become increasingly important for both scientific research and spatial planning. Spatial accessibility and mobility are closely related concepts, as accessibility describes the potential to move by modeling, whereas spatial mobility describes the realized movements of individuals. While both spatial accessibility and mobility have been widely studied, the understanding of how time and temporal change affects accessibility and mobility has been rather limited this far. In the era of ‘big data’, the wealth of temporally sensitive spatial data has made it possible, better than ever, to capture and understand the temporal realities of spatial accessibility and mobility, and hence start to understand better the dynamics of our societies and complex living environment. In this thesis, I aim to develop novel approaches and methods to study the spatio-temporal realities of our living environments via concepts of accessibility and mobility: How people can access places, how they actually move, and how they use space. I inspect these dynamics on several temporal granularities, covering hourly, daily, monthly, and yearly observations and analyses. With novel big data sources, the methodological development and careful assessment of the information extracted from them is extremely important as they are increasingly used to guide decision-making. Hence, I investigate the opportunities and pitfalls of different data sources and methodological approaches in this work. Contextually, I aim to reveal the role of time and the mode of transportation in relation to spatial accessibility and mobility, in both urban and rural environments, and discuss their role in spatial planning. I base my findings on five scientific articles on studies carried out in: Peruvian Amazonia; national parks of South Africa and Finland; Tallinn, Estonia; and Helsinki metropolitan area, Finland. I use and combine data from various sources to extract knowledge from them, including GPS devices; transportation schedules; mobile phones; social media; statistics; land-use data; and surveys. My results demonstrate that spatial accessibility and mobility are highly dependent on time, having clear diurnal and seasonal changes. Hence, it is important to consider temporality when analyzing accessibility, as people, transport and activities all fluctuate as a function of time that affects e.g. the spatial equality of reaching services. In addition, different transport modes should be considered as there are clear differences between them. Furthermore, I show that, in addition to the observed spatial population dynamics, also nature’s own dynamism affects accessibility and mobility on a regional level due to the seasonal variation in river-levels. Also, the visitation patterns in national parks vary significantly over time, as can be observed from social media. Methodologically, this work demonstrates that with a sophisticated fusion of methods and data, it is possible to assess; enrich; harmonize; and increase the spatial and temporal accuracy of data that can be used to better inform spatial planning and decision-making. Finally, I wish to emphasize the importance of bringing scientific knowledge and tools into practice. Hence, all the tools, analytical workflows, and data are openly available for everyone whenever possible. This approach has helped to bring the knowledge and tools into practice with relevant stakeholders in relation to spatial planning

    Dynamic Maps: Representations of Change in Geospatial Modeling and Visualization

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    By coining the descriptive phrase ―user-centric geographic cosmology, Goodchild (1998), challenges the geographically oriented to address GIS in the broadest imaginable context: as interlocutor between persons and geo-phenomena. This investigation responds both in a general way, and more specifically, to the representations of change in GIS modeling and visualization leading to dynamic mapping. The investigation, consisting of a report and a series of experiments, explores and demonstrates prototype workarounds that enhance GIS capabilities by drawing upon ideas, techniques, and components from agent-based modeling and visualization software, and suggests shifts at the conceptual, methodological, and technical levels. The workarounds and demonstrations presented here are four-dimensional visualizations, representing changes and behaviors of different types of entities such as living creatures, mobile assets, features, structures, and surfaces, using GIS, agent-based modeling and animation techniques. In a typical case, a creature begins as a point feature in GIS, becomes a mobile and interactive object in agent-based modeling, and is fleshed out to three dimensions in an animated representation. In contrast, a land surface remains much the same in all three stages. The experiments address change in location, orientation, shape, visual attributes, viewpoint, scale, and speed in applications representing predator-prey, search and destroy, sense and locate and urban sprawl. During the experiments, particular attention is paid to factors of modeling and visualization involved in engaging human sensing and cognitive abilities

    Capturing time in space : dynamic analysis of accessibility and mobility to support spatial planning with open data and tools

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    Understanding the spatial patterns of accessibility and mobility are a key (factor) to comprehend the functioning of our societies. Hence, their analysis has become increasingly important for both scientific research and spatial planning. Spatial accessibility and mobility are closely related concepts, as accessibility describes the potential to move by modeling, whereas spatial mobility describes the realized movements of individuals. While both spatial accessibility and mobility have been widely studied, the understanding of how time and temporal change affects accessibility and mobility has been rather limited this far. In the era of ‘big data’, the wealth of temporally sensitive spatial data has made it possible, better than ever, to capture and understand the temporal realities of spatial accessibility and mobility, and hence start to understand better the dynamics of our societies and complex living environment. In this thesis, I aim to develop novel approaches and methods to study the spatio-temporal realities of our living environments via concepts of accessibility and mobility: How people can access places, how they actually move, and how they use space. I inspect these dynamics on several temporal granularities, covering hourly, daily, monthly, and yearly observations and analyses. With novel big data sources, the methodological development and careful assessment of the information extracted from them is extremely important as they are increasingly used to guide decision-making. Hence, I investigate the opportunities and pitfalls of different data sources and methodological approaches in this work. Contextually, I aim to reveal the role of time and the mode of transportation in relation to spatial accessibility and mobility, in both urban and rural environments, and discuss their role in spatial planning. I base my findings on five scientific articles on studies carried out in: Peruvian Amazonia; national parks of South Africa and Finland; Tallinn, Estonia; and Helsinki metropolitan area, Finland. I use and combine data from various sources to extract knowledge from them, including GPS devices; transportation schedules; mobile phones; social media; statistics; land-use data; and surveys. My results demonstrate that spatial accessibility and mobility are highly dependent on time, having clear diurnal and seasonal changes. Hence, it is important to consider temporality when analyzing accessibility, as people, transport and activities all fluctuate as a function of time that affects e.g. the spatial equality of reaching services. In addition, different transport modes should be considered as there are clear differences between them. Furthermore, I show that, in addition to the observed spatial population dynamics, also nature’s own dynamism affects accessibility and mobility on a regional level due to the seasonal variation in river-levels. Also, the visitation patterns in national parks vary significantly over time, as can be observed from social media. Methodologically, this work demonstrates that with a sophisticated fusion of methods and data, it is possible to assess; enrich; harmonize; and increase the spatial and temporal accuracy of data that can be used to better inform spatial planning and decision-making. Finally, I wish to emphasize the importance of bringing scientific knowledge and tools into practice. Hence, all the tools, analytical workflows, and data are openly available for everyone whenever possible. This approach has helped to bring the knowledge and tools into practice with relevant stakeholders in relation to spatial planning. Keywords: Accessibility; Spatial mobility; Spatio-temporal; Multimodal; Travel time; Open data; Social media; GIS; Data science; Data mining; Spatial planning; National parks; Finland; South Africa; Peruvian Amazonia; Helsinki Region; TallinnAlueellisen saavutettavuuden ja ihmisten liikkumisen rakenteiden hahmottaminen on tärkeää yhteiskunnan toiminnan ymmärtämisessä. Saavutettavuusanalyyseistä on tullut yksi keskeisistä työkaluista alueellisen suunnittelun ja päätöksenteon tueksi. Käsitteinä saavutettavuus ja liikkuminen ovat lähellä toisiaan. Saavutettavuudella tarkoitetaan tyypillisesti ihmisten mahdollisuutta saavuttaa eri paikkoja liikkumalla, kun ihmisten liikkumisen tutkimus keskittyy toteutuneeseen liikkumiseen. Saavutettavuuden ja todellisen liikkumisen alueellisia rakenteita on tutkittu melko paljon eri ympäristöissä. Rakenteiden ajallisten muutosten huomioiminen saavutettavuus- ja liikkumistutkimuksessa on ollut paljon vähäisempää. Nykyiset massiiviset digitaaliset tietoaineistot ovat mahdollistaneet yhteiskunnan eri toimintojen tarkastelun ennennäkemättömällä tarkkuudella niin ajallisesti kuin alueellisestikin. Väitöskirjassani pyrin kehittämään ja soveltamaan uusia lähestymistapoja sekä analyyttisia työkaluja alueellisen saavutettavuuden sekä ihmisten liikkumisen tutkimuksessa. Lisäksi pyrin ymmärtämään kuinka saavutettavuusrakenteet sekä ihmisten liikkumisen rakenteet vaihtelevat ajassa ja tilassa eri aikaperspektiiveillä ulottuen tunneista ja päivistä aina kuukausittaisiin ja vuosienvälisiin tarkasteluihin. Työni anti tieteelliseen keskusteluun on menetelmäpainotteinen, mutta tarjoan myös kontekstisidonnaisia havaintoja tutkimusalueiltani. Uusien tietolähteiden sekä menetelmien suhteen on tärkeää ymmärtää toisaalta niiden tarjoamat mahdollisuudet, mutta myös heikkoudet. Yksi väitöskirjani tavoite onkin tarkastella näitä tekijöitä eri aineistojen ja menetelmien suhteen. Väitöskirjani koostuu johdanto-osasta sekä viidestä tieteellisestä artikkelista. Artikkelit on toteutettu erilaisissa maantieteellisissä ympäristöissä: Perun Amazoniassa, Suomen ja Etelä-Afrikan kansallispuistoissa, Tallinnassa sekä Helsingin metropolialueella. Tulokseni osoittavat, että alueelliset saavutettavuuden ja liikkumisen rakenteet vaihtelevat merkittävästi eri ajankohtina ja niissä on selkeitä päivittäisiä ja kausittaisia vaihteluja. Ajallinen vaihtelu kohdistuu kaikkiin saavutettavuuden komponentteihin, sillä niin liikennejärjestelmä, palveluverkko, kuin ihmisten sijainnitkin vaihtelevat merkittävästi ajassa. Näiden yhteisvaikutuksesta saavutettavuus saattaa samalla alueellakin näyttäytyä eri ajankohtina hyvin erilaisena. Saavuttavuuden ajallinen vaihtelu olisikin tärkeää huomioida entistä paremmin esimerkiksi suunnittelussa. Lisäksi saavutettavuuden alueelliset rakenteet näyttäytyvät hyvin erilaisina riippuen siitä, millä kulkutavalla saavutettavuutta mallinnetaan. Autoilijan saavutettavuustodellisuus on toisenlainen kuin joukkoliikenteen käyttäjän. Tulokseni osoittavat, että myös luonnon dynamiikalla voi olla suuri merkitys saavutettavuuteen. Esimerkiksi Amazonian jokien vedenkorkeuden vuodenaikainen vaihtelu vaikuttaa suuresti navigoimiseen ja saavutettavuusrakenteisiin alueellisella tasolla. Liikenneverkon dynaamisuuden lisäksi myös ihmisten liike, ja ihmisten sijainnin dynaamisuus, tulisi ottaa huomioon saavutettavuusmallinnuksessa. Ihmisten vaihtelevien sijaintien tutkimus on perinteisesti vaikeaa, mutta uusilla aineistolähteillä, kuten sosiaalisella medialla, voidaan tuottaa tästä uutta tietoa. Toisaalta dynaaminen saavutettavuus on pitkälti riippuvainen kohdepisteiden, kuten palveluiden alueellisista rakenteista. Alueilla joissa liikenneverkko on melko vakiintunut, palveluiden rakennemuutoksilla saattaa olla liikennehankkeita suurempi vaikutus saavutettavuuteen. Menetelmällisesti väitöskirjani osoittaa eri datalähteiden ja menetelmien yhdistelyn tärkeyden datan spatiaalisen ja ajallisen tarkkuuden parantamisessa, yhdenmukaistamisessa, laadun arvioimisessa, ja rikastamisessa. Lopuksi haluan korostaa tieteellisen tiedon, menetelmien ja aineistojen avoimuuden tärkeyttä, sillä sen avulla tehty työ on mahdollista saada tehokkaasti osaksi käytännön suunnittelua ja päätöksentekoa. Väitöskirjassani kehittämäni työkalut ja sen aikana tuotetut datat onkin julkaistu pääsääntöisesti avoimesti. Tämän ansiosta niitä voidaan vapaasti hyödyntää ja niiden laatua voidaan arvioida kriittisesti. Avoimuuden seurauksena työssä kehitetyt menetelmät ovat jo päätyneet osaksi käytännön aluesuunnittelutyötä. Asiasanat: Saavutettavuus; Liikkuminen; Aika-tilallisuus; Multimodaalisuus; Matka-aika; Avoin data; GIS; Sosiaalinen media; Datatiede; Tiedonlouhinta; Alueellinen suunnittelu; Kansallispuistot; Suomi; Etelä-Afrikka; Perun Amazonia; Pääkaupunkiseutu; Tallinn

    An Agent-Based Variogram Modeller: Investigating Intelligent, Distributed-Component Geographical Information Systems

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    Geo-Information Science (GIScience) is the field of study that addresses substantive questions concerning the handling, analysis and visualisation of spatial data. Geo- Information Systems (GIS), including software, data acquisition and organisational arrangements, are the key technologies underpinning GIScience. A GIS is normally tailored to the service it is supposed to perform. However, there is often the need to do a function that might not be supported by the GIS tool being used. The normal solution in these circumstances is to go out and look for another tool that can do the service, and often an expert to use that tool. This is expensive, time consuming and certainly stressful to the geographical data analyses. On the other hand, GIS is often used in conjunction with other technologies to form a geocomputational environment. One of the complex tools in geocomputation is geostatistics. One of its functions is to provide the means to determine the extent of spatial dependencies within geographical data and processes. Spatial datasets are often large and complex. Currently Agent system are being integrated into GIS to offer flexibility and allow better data analysis. The theis will look into the current application of Agents in within the GIS community, determine if they are used to representing data, process or act a service. The thesis looks into proving the applicability of an agent-oriented paradigm as a service based GIS, having the possibility of providing greater interoperability and reducing resource requirements (human and tools). In particular, analysis was undertaken to determine the need to introduce enhanced features to agents, in order to maximise their effectiveness in GIS. This was achieved by addressing the software agent complexity in design and implementation for the GIS environment and by suggesting possible solutions to encountered problems. The software agent characteristics and features (which include the dynamic binding of plans to software agents in order to tackle the levels of complexity and range of contexts) were examined, as well as discussing current GIScience and the applications of agent technology to GIS, agents as entities, objects and processes. These concepts and their functionalities to GIS are then analysed and discussed. The extent of agent functionality, analysis of the gaps and the use these technologies to express a distributed service providing an agent-based GIS framework is then presented. Thus, a general agent-based framework for GIS and a novel agent-based architecture for a specific part of GIS, the variogram, to examine the applicability of the agent- oriented paradigm to GIS, was devised. An examination of the current mechanisms for constructing variograms, underlying processes and functions was undertaken, then these processes were embedded into a novel agent architecture for GIS. Once the successful software agent implementation had been achieved, the corresponding tool was tested and validated - internally for code errors and externally to determine its functional requirements and whether it enhances the GIS process of dealing with data. Thereafter, its compared with other known service based GIS agents and its advantages and disadvantages analysed

    A CAD-based modeling for dynamic visualization of urban environments in piecemeal (incremental) growth

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    Thesis (Master)--Izmir Institute of Technology, City and Regional Planning, Izmir, 2002Includes bibliographical references (leaves: 114-122)Text in English; Abstract: Turkish and Englishxi, 122 leavesVisualization is inherent to the conduct of urban design as a direct connection between the designer and three dimensional reality of urban settlements. Visualization of urban environments and urban design projects is vital, since most designers prefer to understand place and context through visualization. The reasons for visualization in urban design can be classified under three headings: .visual thinking, design communication and testing mechanism. Digital revolution. has improved computer use in urban design, as in many other fields. Dynamic computer models can present an ideal environment to visualize the change in respect to time. Digital tools are much more efficient than conventional methods in explaining the growth and change of urban environments. Especially, incremental growth requires features not found in .static/analog. media. Christopher Alexander and his colleagues, in their book .A New Theory of Urban Design., tried to justify their ideas about piecemeal growth by an experiment. The analog methods, such as physical models, two-dimensional diagrams, have been used to conduct the experiment and to convey their ideas about the design process. This thesis tries to produce a .dynamic/digital. model that could be utilized in their experiment instead of static/analog methods. Spatial data should be considered as dynamic, or changing identities rather than as simple, static features. Time is an example of a dynamic component of a spatial data set. Recent technological developments are increasing computer hardware and software capabilities so that this dynamic aspect of data can be accounted for by today.s systems. Dynamic data have not been a great concern in digital technologies for many years, but today changing patterns and dimensions are becoming more important

    L'analisi spaziale

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    The so-called data deluge, along with ever-increasing technological capabilities, tantalizes geographers with exciting opportunities for spatial data analysis. These opportunities come with challenges, because data and technology, alone, cannot address the pressing questions of our world. Spatial analysis, a.k.a. spatial statistics, is a lot more than colourful maps and attractive displays: still relatively underrepresented in the Italian geography, this discipline has grown from a strictly quantitative niche to part of a critical spatial science and continues to stimulate new developments in statistics because, as we know, spatial is special. This book, published in the series “New Geographies. Work Tools”, adds spatial analysis to the Italian geographer’s toolbox. Not a how-to manual, it presents some of the core analytical issues through the redundancy of narrative language and mathematical language. It traces the journey of spatial analysis from its roots in quantitative geography, GIS, and statistics, towards the definition of its own identity and the acceptance of its own relativity and limitations. It discusses the relationship of spatial analysis with GIScience and its efforts to embed critiques within its own discourse, emphasizing the role of theory, the importance of hypothesis testing, and acknowledging the ethics surrounding the use and analysis of data. A few examples illustrate practical implementations, showing the value added by spatial statistics in yielding reliable analyses that can support management decisions. It concludes with a brief outlook on the Italian geographic literature, where spatial analysis – like elsewhere – can play a role in competently accepting today’s opportunities and challenges, in a constructive dialogue within geography as a whole
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