144 research outputs found

    Topograafiliste kaartide temaatiline Ôigsus ja tÀielikkus

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    VĂ€itekirja elektrooniline versioon ei sisalda publikatsiooneSuuremÔÔtkavalised topograafilised kaardid on tĂ€napĂ€eva ruumiandmete taristute lahutamatuks osaks. TĂ€nu sellele on kaardil kujutatud andmete kasutajaskond laialdane alates nii riigi- kui omavalitsusest ja lĂ”petades hariduse vĂ”i ettevĂ”tlusvaldkonnaga. Suur kasutajaskond eeldab andmetelt kĂ”rget kvaliteeti. Ruumiandmete kvaliteediga on nii teadlased kui ruumiandmete tootjad tegelenud ĂŒle 40 aasta. Ühe suurima saavutusena nimetavad mitmed autorid (Devillers, R. et al., 2010; Hunter et al., 2009) ISO 19100 ruumiandmete kvaliteedi standardite loomist. Rahvuslike kaardistusagentuuride katusorganisatsiooni Eurogeographics’i 2018. a uurimus nĂ€itab, et INSPIREga ĂŒhinenud liikmete seas on ruumiandmete kvaliteedi standardite kasutus suurenenud. Samas tuuakse vĂ€lja ka kvaliteedi valdkonna mĂ”ned kitsaskohad. Üheks suuremaks puuduseks on see, et kvaliteeti kĂ€sitletakse monotoonsena, mis kogu ruumiandmekogu ulatuses omab ĂŒhesugust vÀÀrtust. Tegelikult peaks kvaliteeti analĂŒĂŒsima ning vÀÀrtuseid esitama suurema detailsusega kas vĂ€iksemate territoriaalsete ĂŒksuste kohta, nĂ€htuskihtide kohta vĂ”i mĂ”ne muu omaduse, nĂ€iteks kaardistuse teinud vĂ€litöötaja, jĂ€rgi moodustatud alamhulga kohta. Detailsem kvaliteedi analĂŒĂŒs ning saadud nĂ€itajate esitamine on vajalik nii andmetootjatele kvaliteedi paremaks tagamiseks kui ka kasutajatele. Doktoritöös on kasutatud Eesti pĂ”hikaardi 1:10 000 vĂ€litööde kontrolli andmeid aastatest 2003-2006. Töö eesmĂ€rgiks on uurida vĂ€litöötajate mĂ”ju topograafilise kaardistuse kvaliteedile. PĂ”hiliselt on analĂŒĂŒsitud klassifitseerimise Ă”igsust ning tĂ€ielikkust, mida kirjeldati liigsete ja puuduvate objektide nĂ€itajatega. VĂ€likaardistusel tehtud vigu ja nende struktuuri analĂŒĂŒsiti kahel tasandil: 1) ĂŒldisel tasandil, kus analĂŒĂŒsis osalesid kĂ”ik andmebaasis olnud vead korraga; 2) detailsel tasandil, kus vigu analĂŒĂŒsiti vĂ€litöötajate lĂ”ikes (II teadusartikkel). Topograafiliste andmete kvaliteet vĂ”ib erineda ka ruumiliselt. Selle pĂ”hjuseks vĂ”ib olla maastiku keerukus, vĂ€litöötaja sugu, kogemus ning vĂ”imekus maastikku tĂ”lgendada. KĂ€esolevas doktoritöös uuriti kas ja mil mÀÀral mĂ”jutavad kaardistuse kvaliteeti vĂ€litöötaja teatud omadused ning maastiku keerukus (III teadusartikkel). Vektorandmetest maastiku keerukuse indeksite arvutamiseks töötati vĂ€lja metoodika, mille abil vĂ€iksed punkt ning joonobjektid lĂ”imiti ĂŒhtseks pinnakatte kihiks (I teadusartikkel). Reaalne maailm on pidevas muutumise. SeetĂ”ttu vajab topograafiline andmestik pidevat kaasajastamist ehk uut kaardistamist, mis on ressursimahukas ja kallis. TĂ€napĂ€eval on ĂŒhe potentsiaalse vĂ”imalusena uuritud vabatahtlikke kaardistajate poolt toodetud andmestiku (VGI) kvaliteetsust ning kasutamist kaasajastamise protsessis. Doktoritöö nĂ€itas, et ĂŒldisel ja detailsel tasandil tehtud kaardistusvigade analĂŒĂŒsid andsid teatud juhtudel erinevaid tulemusi ning teatud juhtudel sarnaseid tulemusi. Vead, mis ilmnesid mĂ”lemal tasandil, olid sĂŒsteemsed, teisel juhul aga pĂ”hjustatud peamiselt ĂŒksikutest vĂ€litöötajatest. NĂ€htused, mis olid kriitilisemad mĂ”lema tasandi analĂŒĂŒsides, olid kivihunnik, vundament, harvik, rada, siht ja salu. VĂ€litöötaja sugu kaardistuse kvaliteeti ei mĂ”jutanud. Samas vĂ€ikse töökogemusega vĂ€litöötajate kaardistuskvaliteet oli kĂ”rgem, kui keskmise töökogemusega vĂ€litöötajatel ning kvaliteet tĂ”usis jĂ€llegi vĂ€ga kogenud töötajatel. AnalĂŒĂŒsi tulemused nĂ€itasid, et hoonestatud-mitmekesises maastikutĂŒĂŒbis oli vĂ€litöötajate lĂ”ikes kaardistuse kvaliteet kĂ”rgem, kui avatud-lihtsas vĂ”i suletud-keerukas maastikutĂŒĂŒbis. Sarnastele tulemustele on jĂ”udnud ka mitmed VGI kvaliteeti uurinud autorid. Kaardistuse kvaliteedi tĂ”stmiseks tuleks sĂŒsteemsete vigade vĂ€ltimiseks tĂ€iendada kaardistusjuhendeid – tĂ€psustada nĂ€htuse definitsiooni vĂ”i tunnuseid vĂ”i kaaluda, kas antud nĂ€htuse kaardistamine on ĂŒldse vajalik. Individuaalsete, ĂŒksikute vĂ€litöötajate pĂ”hjustatud vigade vĂ€ltimiseks on soovitav viia lĂ€bi koolitusi. Samuti vĂ”iks vĂ€litöötaja valida endale sobiva maastikutĂŒĂŒbi kaardistamise, sest uuringud on nĂ€idanud, et sobiv maastik tĂ”stab turvalisust ning enesekindlust ja seelĂ€bi ka kvaliteeti.The availability of quality topographic databases and associated maps is critical for all users of spatial data. Various governmental agencies, first responders, utilities and GIS practitioners rely on the completeness and thematic accuracy of national topographic datasets. Spatial data quality has been the subject of discussions for almost 40 years. One of the biggest achievements of that period was agreement in international standards for spatial data quality. National mapping agencies involved in INSPIRE, are users of the ISO 19100 quality standards or the others spatial data quality standards. By contrast, the biggest problem is that data quality is analysed and presented at a generic global level rather than at more detailed levels of granularity. More detailed quality information is needed for data users and data producers as well. An analysis of topographical Estonian Basic Map, empirical field inspections from 2003-2006 provides an excellent case study to investigate the effect of characteristics of field workers on spatial data quality. Mainly three quality elements are considered: classification correctness, omission, and commission. The error analyses published in II paper were performed on two levels: in general across all map sheets and in detail according to the field workers involved. The quality of topographical maps may vary spatially, also. The variation of the interpretation of orthophotos on the field may occur due to the differences in the complexity of the landscape, differences in the characteristics of individual field workers, and differences in their perception of the landscape. In the III publication the interaction between the characteristics of field workers, including their gender and years of experience (as a proxy for their mapping skills), and landscape heterogeneity were explored. In order to obtain landscape indicators describing landscape heterogeneity, the methodology of calculation of landscape indicators for vector data was developed (I publication). Results showed the importance of error analyses on the level of a field worker and by landscapes as well. The outcomes reveal that the structure of errors on the general level and field workers’ level is different by geometry and error types. However, both systematic and individual errors were evident. Gender and years of experience of the field workers did not have a statistically significant impact on the mapping quality. By contrast, the results showed differences in the rates of misclassification, omission, and commission errors between field workers in different landscape types. To improve the mapping quality concerning systematic errors, it is necessary to revise the definitions or methods of determination in a mapping specification or to consider whether the mapping of these features is absolutely necessary. In case of individual errors, monitoring field work to detect errors, so that workers can be trained to avoid such errors in the future, would also improve the mapping accuracy.

    What explains inconsistencies in field-based ecosystem mapping?

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    Questions: Field-based ecosystem mapping is prone to observer bias, typically resulting in a mismatch between maps made by different mappers, that is, inconsistency. Experimental studies testing the influence of site, mapping scale, and differences in experience level on inconsistency in field-based ecosystem mapping are lacking. Here, we study how inconsistencies in field-based ecosystem maps depend on these factors. Location: IĆĄkoras and Guollemuorsuolu, northeastern Norway, and Landsvik and Lygra, western Norway. Methods: In a balanced experiment, four sites were field-mapped wall-to- wall to scales 1:5000 and 1:20,000 by 12 mappers, representing three experience levels. Thematic inconsistency was calculated by overlay analysis of map pairs from the same site, mapped to the same scale. We tested for significant differences between sites, scales, and experience-level groups. Principal components analysis was used in an analysis of additional map inconsistencies and their relationships with site, scale and differences in experience level and time consumption were analysed with redundancy analysis. Results: On average, thematic inconsistency was 51%. The most important predictor for thematic inconsistency, and for all map inconsistencies, was site. Scale and its interaction with site predicted map inconsistencies, but only the latter were important for thematic inconsistency. The only experience-level group that differed significantly from the mean thematic inconsistency was that of the most experienced mappers, with nine percentage points. Experience had no significant effect on map inconsistency as a whole. Conclusion: Thematic inconsistency was high for all but the dominant thematic units, with potentially adverse consequences for mapping ecosystems that are fragmented or have low coverage. Interactions between site and mapping system properties are considered the main reasons why no relationships between scale and thematic inconsistency were observed. More controlled experiments are needed to quantify the effect of other factors on inconsistency in field-based mapping. classification, experience, field-based mapping, GIS, inter-observer variation, land-cover mapping, landscape metrics, ordination, scale, vegetation mappingpublishedVersio

    Geoinformatics in Citizen Science

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    The book features contributions that report original research in the theoretical, technological, and social aspects of geoinformation methods, as applied to supporting citizen science. Specifically, the book focuses on the technological aspects of the field and their application toward the recruitment of volunteers and the collection, management, and analysis of geotagged information to support volunteer involvement in scientific projects. Internationally renowned research groups share research in three areas: First, the key methods of geoinformatics within citizen science initiatives to support scientists in discovering new knowledge in specific application domains or in performing relevant activities, such as reliable geodata filtering, management, analysis, synthesis, sharing, and visualization; second, the critical aspects of citizen science initiatives that call for emerging or novel approaches of geoinformatics to acquire and handle geoinformation; and third, novel geoinformatics research that could serve in support of citizen science

    Spatiotemporal enabled Content-based Image Retrieval

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    Space time geography of Malaria and the environmental risks to households, Lagos State, Nigeria

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    Phd ThesisThe research employs the theoretical lens of human ecology of disease to examine the ecology of malaria in Lagos state, Nigeria. As a first step I examine the spatial and temporal trends in clinical malaria infection using a density-based algorithm to identify two locations (Ikeja and Kosofe LGAs) with one of the highest malaria infection rates and ecologically diverse terrain. They form the focus of this research. I gather data and derive measures on 26 theoretically relevant environment and socio-cultural risk variables in a cross-section of 208 households using mixed methods that comprise semi-structured interviews, a questionnaire, environmental observations, GIS and remote sensing data and GPS mapping. Through these efforts, I build a household spatial database. I assess the contributory influences of the risk variables through the development and assessment of ten ecologically relevant candidate models of urban malaria using statistical and GIS analysis. I also engage with the everyday lives of the households and qualify the quantitative relationships. Findings reveal that the most parsimonious candidate model is grounded on the human ecology of disease principle. While many of the variables are not statistically significant, some, such as travel history, animal presence and household size, are of public health importance. One important finding emerges. The risk variable “working at night without mosquito protection”, though it does not appear in this model, seems to be important across other models. I examine it further and note that its risk within households is higher than those associated with residential locations. In fact, households inhabit low-risk locations and have low vulnerability risk rates. This suggests that in urban areas, infection likely occurs outside homes and mostly from places of work or social gathering, and coincides with older household members rather than vulnerable children. This research suggests further insights for urban-like occupations and behaviours.Dorothy Hodgkin Postgraduate Award (NERC & Shell BP), Newcastle University and the Nigerian Petroleum Technology Development Fund

    Radar satellite imagery for humanitarian response. Bridging the gap between technology and application

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    This work deals with radar satellite imagery and its potential to assist of humanitarian operations. As the number of displaced people annually increases, both hosting countries and relief organizations face new challenges which are often related to unclear situations and lack of information on the number and location of people in need, as well as their environments. It was demonstrated in numerous studies that methods of earth observation can deliver this important information for the management of crises, the organization of refugee camps, and the mapping of environmental resources and natural hazards. However, most of these studies make use of -high-resolution optical imagery, while the role of radar satellites is widely neglected. At the same time, radar sensors have characteristics which make them highly suitable for humanitarian response, their potential to capture images through cloud cover and at night in the first place. Consequently, they potentially allow quicker response in cases of emergencies than optical imagery. This work demonstrates the currently unused potential of radar imagery for the assistance of humanitarian operations by case studies which cover the information needs of specific emergency situations. They are thematically grouped into topics related to population, natural hazards and the environment. Furthermore, the case studies address different levels of scientific objectives: The main intention is the development of innovative techniques of digital image processing and geospatial analysis as an answer on the identified existing research gaps. For this reason, novel approaches are presented on the mapping of refugee camps and urban areas, the allocation of biomass and environmental impact assessment. Secondly, existing methods developed for radar imagery are applied, refined, or adapted to specifically demonstrate their benefit in a humanitarian context. This is done for the monitoring of camp growth, the assessment of damages in cities affected by civil war, and the derivation of areas vulnerable to flooding or sea-surface changes. Lastly, to foster the integration of radar images into existing operational workflows of humanitarian data analysis, technically simple and easily-adaptable approaches are suggested for the mapping of rural areas for vaccination campaigns, the identification of changes within and around refugee camps, and the assessment of suitable locations for groundwater drillings. While the studies provide different levels of technical complexity and novelty, they all show that radar imagery can largely contribute to the provision of a variety of information which is required to make solid decisions and to effectively provide help in humanitarian operations. This work furthermore demonstrates that radar images are more than just an alternative image source for areas heavily affected by cloud cover. In fact, what makes them valuable is their information content regarding the characteristics of surfaces, such as shape, orientation, roughness, size, height, moisture, or conductivity. All these give decisive insights about man-made and natural environments in emergency situations and cannot be provided by optical images Finally, the findings of the case studies are put into a larger context, discussing the observed potential and limitations of the presented approaches. The major challenges are summarized which need be addressed to make radar imagery more useful in humanitarian operations in the context of upcoming technical developments. New radar satellites and technological progress in the fields of machine learning and cloud computing will bring new opportunities. At the same time, this work demonstrated the large need for further research, as well as for the collaboration and transfer of knowledge and experiences between scientists, users and relief workers in the field. It is the first extensive scientific compilation of this topic and the first step for a sustainable integration of radar imagery into operational frameworks to assist humanitarian work and to contribute to a more efficient provision of help to those in need.Die vorliegende Arbeit beschĂ€ftigt sich mit bildgebenden Radarsatelliten und ihrem potenziellen Beitrag zur UnterstĂŒtzung humanitĂ€rer EinsĂ€tze. Die jĂ€hrlich zunehmende Zahl an vertriebenen oder geflĂŒchteten Menschen stellt sowohl AufnahmelĂ€nder als auch humanitĂ€re Organisationen vor große Herausforderungen, da sie oft mit unĂŒbersichtlichen VerhĂ€ltnissen konfrontiert sind. Effektives Krisenmanagement, die Planung und Versorgung von FlĂŒchtlingslagern, sowie der Schutz der betroffenen Menschen erfordern jedoch verlĂ€ssliche Angaben ĂŒber Anzahl und Aufenthaltsort der GeflĂŒchteten und ihrer natĂŒrlichen Umwelt. Die Bereitstellung dieser Informationen durch Satellitenbilder wurde bereits in zahlreichen Studien aufgezeigt. Sie beruhen in der Regel auf hochaufgelösten optischen Aufnahmen, wĂ€hrend bildgebende Radarsatelliten bisher kaum Anwendung finden. Dabei verfĂŒgen gerade Radarsatelliten ĂŒber Eigenschaften, die hilfreich fĂŒr humanitĂ€re EinsĂ€tze sein können, allen voran ihre UnabhĂ€ngigkeit von Bewölkung oder Tageslicht. Dadurch ermöglichen sie in KrisenfĂ€llen verglichen mit optischen Satelliten eine schnellere Reaktion. Diese Arbeit zeigt das derzeit noch ungenutzte Potenzial von Radardaten zur UnterstĂŒtzung humanitĂ€rer Arbeit anhand von Fallstudien auf, in denen konkrete Informationen fĂŒr ausgewĂ€hlte Krisensituationen bereitgestellt werden. Sie sind in die Themenbereiche Bevölkerung, Naturgefahren und Ressourcen aufgeteilt, adressieren jedoch unterschiedliche wissenschaftliche AnsprĂŒche: Der Hauptfokus der Arbeit liegt auf der Entwicklung von innovativen Methoden zur Verarbeitung von Radarbildern und rĂ€umlichen Daten als Antwort auf den identifizierten Forschungsbedarf in diesem Gebiet. Dies wird anhand der Kartierung von FlĂŒchtlingslagern zur AbschĂ€tzung ihrer Bevölkerung, zur Bestimmung von Biomasse, sowie zur Ermittlung des Umwelteinflusses von FlĂŒchtlingslagern aufgezeigt. DarĂŒber hinaus werden existierende oder erprobte AnsĂ€tze fĂŒr die Anwendung im humanitĂ€ren Kontext angepasst oder weiterentwickelt. Dies erfolgt im Rahmen von Fallstudien zur Dynamik von FlĂŒchtlingslagern, zur Ermittlung von SchĂ€den an GebĂ€uden in Kriegsgebieten, sowie zur Erkennung von Risiken durch Überflutung. Zuletzt soll die Integration von Radardaten in bereits existierende AblĂ€ufe oder Arbeitsroutinen in der humanitĂ€ren Hilfe anhand technisch vergleichsweise einfacher AnsĂ€tze vorgestellt und angeregt werden. Als Beispiele dienen hier die radargestĂŒtzte Kartierung von entlegenen Gebieten zur UnterstĂŒtzung von Impfkampagnen, die Identifizierung von VerĂ€nderungen in FlĂŒchtlingslagern, sowie die Auswahl geeigneter Standorte zur Grundwasserentnahme. Obwohl sich die Fallstudien hinsichtlich ihres Innovations- und KomplexitĂ€tsgrads unterscheiden, zeigen sie alle den Mehrwert von Radardaten fĂŒr die Bereitstellung von Informationen, um schnelle und fundierte Planungsentscheidungen zu unterstĂŒtzen. DarĂŒber hinaus wird in dieser Arbeit deutlich, dass Radardaten fĂŒr humanitĂ€re Zwecke mehr als nur eine Alternative in stark bewölkten Gebieten sind. Durch ihren Informationsgehalt zur Beschaffenheit von OberflĂ€chen, beispielsweise hinsichtlich ihrer Rauigkeit, Feuchte, Form, GrĂ¶ĂŸe oder Höhe, sind sie optischen Daten ĂŒberlegen und daher fĂŒr viele Anwendungsbereiche im Kontext humanitĂ€rer Arbeit besonders. Die in den Fallstudien gewonnenen Erkenntnisse werden abschließend vor dem Hintergrund von Vor- und Nachteilen von Radardaten, sowie hinsichtlich zukĂŒnftiger Entwicklungen und Herausforderungen diskutiert. So versprechen neue Radarsatelliten und technologische Fortschritte im Bereich der Datenverarbeitung großes Potenzial. Gleichzeitig unterstreicht die Arbeit einen großen Bedarf an weiterer Forschung, sowie an Austausch und Zusammenarbeit zwischen Wissenschaftlern, Anwendern und EinsatzkrĂ€ften vor Ort. Die vorliegende Arbeit ist die erste umfassende Darstellung und wissenschaftliche Aufarbeitung dieses Themenkomplexes. Sie soll als Grundstein fĂŒr eine langfristige Integration von Radardaten in operationelle AblĂ€ufe dienen, um humanitĂ€re Arbeit zu unterstĂŒtzen und eine wirksame Hilfe fĂŒr Menschen in Not ermöglichen

    2019 EC3 July 10-12, 2019 Chania, Crete, Greece

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    De-Sign Environment Landscape City Atti

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    La VI Conferenza Internazionale sul Disegno, De_Sign Environment Landscape City_Genova 2020 tratta di: Rilievo e Rappresentazione dell’Architettura e dell’Ambiente; Il Disegno per il paesaggio; Disegni per il Progetto: tracce - visioni e pre-visioni; I margini i segni della memoria e la città in progress; Cultura visiva e comunicazione dall’idea al progetto; Le emergenze architettoniche; Il colore e l’ambiente; Percezione e identità territoriale; Patrimonio iconografico culturale paesaggistico: arte, letteratura e ricadute progettuali; Segni e Disegni per il Design e Rappresentazione avanzata. Federico Babina, architetto e graphic designer presenta ARCHIVISION, e Eduardo Carazo Lefort, Docente dell’Università di Valladolid e Targa d’Oro dell’Unione Italiana Disegno la Lectio Magistralis. The VI International Conference on Drawing, De_Sign Environment Landscape City_Genoa 2020, deals with: Survey and Representation of Architecture and the Environment; Drawing for the landscape; De-signs for the Project: traces-visions and previews; Margins, signs of memory and the city in progress; Visual culture and communication from idea to project; Architectural emergencies; The color and the environment; Perception and territorial identity; Landscape cultural iconographic heritage: art, literature and design implications; Signs and Drawings for Design and Advanced Representation. Federico Babina, architect and graphic designer presents ARCHIVISION, and Professor Eduardo Carazo Lefort-University of Valladolid and Gold Plate of the Italian Design Union presents his Lectio Magistralis
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