2022 |
Apostolopoulos, Konstantinos; Potsiou, Chryssy How to Improve Quality of Crowdsourced Cadastral Surveys Journal Article In: Land, vol. 11, no. 10, pp. 1642, 2022, ISSN: 2073-445X. Abstract | Links | BibTeX | Tags: cadastral basemap, Cadastre, Crowdsourcing, Land administration, quality controls @article{apostolopoulos2022improve,The potential for introducing voluntary citizen participation, combined with mobile services, for cadastral data collection for a systematic first registration has been thoroughly investigated and even implemented in some official projects. This data collection procedure can technically be ac-complished safely, but results have shown that many participants have difficulty in identifying the land parcels (location, shape and size) on the base-map (orthophoto, air-photo, etc.) correctly. Either they have to ask the assistance of a private professional, or there is a high risk that a number of errors may appear in the submitted crowdsourced data. This paper investigates how to improve the quality of such crowdsourced cadastral data, by adding to the base-map any available and relevant geospatial and descriptive information that may help the participants to correctly identify their land parcel. In particular, the research investigates and suggests (a) which types of available geospatial information should be added to the base-map and by whom (professionals or a group of trained volunteers), and (b) the necessary quality controls that must be made in the compilation of the advanced crowdsourced base-map—a case study follows to assess the suggested proposal. In addition, this paper provides an updated version of the crowdsourced methodology for cadastral surveys as modelled by the authors in an earlier stage of their research. This updated version briefly includes all quality controls needed to ensure the quality of a modern cadastre that the authors will further investigate in a subsequent stage. |
2021 |
Gkeli, Maria; Potsiou, Chryssy; Ioannidis, Charalabos BIM data as Input to 3D Crowdsourced Cadastral Surveying-Potential and Perspectives Proceedings Article In: 2021. Abstract | Links | BibTeX | Tags: 3D cadastre, BIM, Crowdsourcing, Land administration @inproceedings{nokey,So far traditional procedures have often led to increased costs and long delays in the 2D cadastral surveying procedures, making the completion of first registration difficult or even impossible for many countries. In the meantime, the ongoing urbanization has led to the construction of complex buildings with multi-dimensional property rights even in countries with poor and incomplete 2D land administration systems (LAS). This new urban reality though, requires the establishment of modern 3D LAS to protect and secure property Rights, Restrictions and Responsibilities (RRRs) within the three-dimensional environment. Fortunately, crowdsourcing and VGI have recently claimed a critical role as a reliable methodology with an increased potential for affordable and fast systematic registration of both 2D and 3D cadastral data. It has also become clear that a nationwide cadastral system may be comprised of various datasets of varying geometric accuracies integrated together in a fit-for-purpose whole. In the meantime, many cities, regardless of the progress in establishing good land administration systems, are mapped in 3D at various levels of detail and have complex buildings designed, constructed and managed by Building Information Modeling (BIM). Linking cadastral information to the 3D digital representations of the man-made environment could be a promising approach in order to define, declare and visualize the complex 3D cadastral space units. The integration of geospatial information derived from existing BIM with the LAS and the use of crowdsourcing methodology to identify the 3D cadastral objects and declare related rights and other necessary information, may significantly speed up the implementation of multipurpose 3D LAS. Utilizing the Information and Communication Technology (ICT) tools, low-cost equipment, crowdsourcing techniques, web services, open-source software and BIM, the development of a reliable, qualitative and affordable solution for the initial implementation of a 3D cadastre is feasible. This research focuses on how BIM information and crowdsourcing techniques can be combined together to improve the compilation process of a 3D cadastre. The main objective is to investigate and discuss how these domains may interact and cooperate to serve the needs of the systematic 3D Cadastral registration. An innovative 3D crowdsourced cadastral procedure which will also integrate available BIM data is designed, tested and evaluated, aiming to save time and funds and provide a solution for the initial registration and visualization of 3D cadastral data. An open-sourced web application for the visualization and manipulation of BIM data is developed and tested. The user of the application is able to zoom in and out of the scene, make 3D measurements, create vertical and horizontal slices of the building in order to reveal hidden entities, helping him/her to recognize and identify each property unit, and finally insert all the necessary cadastral information, updating the system with new data. The proposed BIM data as Input to 3D Crowdsourced Cadastral Surveying-Potential and Perspectives (11069) Maria Gkeli, Chryssy Potsiou and Charalabos Ioannidis (Greece) FIG e-Working Week 2021 Smart Surveyors for Land and Water Management-Challenges in a New Reality Virtually in the Netherlands, 21-25 June 2021 crowdsourced framework is tested on a multi-storey building in Athens, Greece. The main potential, perspectives and reliability of such an implementation are assessed and discussed. |
Apostolopoulos, Konstantinos; Potsiou, Chryssy Consideration on how to introduce gamification tools to enhance citizen engagement in crowdsourced cadastral surveys Journal Article In: Surv. Rev., vol. 54, no. 383, pp. 142–152, 2021, ISSN: 0039-6265. Abstract | Links | BibTeX | Tags: Cadastral surveying, Citizen participation, Crowdsourcing, Gamification, Land administration, VGI @article{apostolopoulos2022consideration,The major objective of this research is to investigate the progress of citizen participation in cadastral surveying and to consider ways on how to introduce gamification tools for further improvement. A brief literature review is presented in the areas of the Sustainable Development Agenda 2030 related to land administration and citizen engagement, e-government and citizen participation and gamification tools for citizen engagement. This paper, also, includes an investigation of the progress in introducing volunteerism and citizen participation to the Hellenic Cadastre. A case study is held by a group of volunteers in order to assess the developed tools designed either by the private sector or by the cadastral agency. |
2020 |
Mourafetis, George; Potsiou, Chryssy In: ISPRS Int. J. Geo-Information, vol. 9, no. 4, pp. 190, 2020, ISSN: 22209964. Abstract | Links | BibTeX | Tags: Cadaster, Crowdsourcing, Land administration, Mobile services, VGI @article{Mourafetis2020,Greece is one of the few European countries that has not yet a fully operating Cadastre at national coverage. Cadastral surveying and property registration have been completed only for about 8% of the Greek territory, which includes about 18% of the total property rights. At the remaining areas, cadastral surveying and property registration is still under development and is expected to be completed by the end of 2021. The cadastral survey is a participatory procedure in which property right holders, or their representatives, are expected to declare the land parcels on which they have property rights and submit all documents that prove these rights. The time frame available for the declaration is 3 months, which is specific for each municipality. Right holders are now enabled to provide both spatial and descriptive information, regarding their properties and property rights, without the need of a professional. That includes the parcel's boundary lines along with the legal documents required to validate the declaration. Each right holder, or a representative, has the option to submit a declaration over the internet through a web application without the need of a professional. Within the frame of a PhD research, several concerns were addressed such as usability, security, and scalability in order for the outcome to support its scope while respecting binding constrains. As a result, two web applications have been created to officially support the Hellenic Cadaster property rights declaration process. The suggested approach was considered a big success in terms of both public acceptance and usability as shown from the statistics collected during the first eight months of its formal operation. |
Potsiou, Chryssy; Paunescu, Cornel; Ioannidis, Charalabos; Apostolopoulos, Konstantinos; Nache, Florin Reliable 2D Crowdsourced Cadastral Surveys: Case Studies from Greece and Romania Journal Article In: ISPRS Int. J. Geo-Information, vol. 9, no. 2, pp. 89, 2020, ISSN: 2220-9964. Abstract | Links | BibTeX | Tags: Cadastre, Crowdsourcing, Land administration, opensource @article{Potsiou2020,This paper is part of a doctoral dissertation (PhD) research that investigates the development of a procedure for reliable 2D crowdsourced cadastral surveying introducing the use of new Information Technology IT tools and increased citizen participation, supported by m-services. For the development of this procedure, the formal cadastral procedure applied currently in two Europeans countries, Greece and Romania, for their modern nation-wide projects is firstly investigated. The first part of this paper briefly investigates the current stage of progress of those projects in both countries, as well as the specifications and procedures applied for the cadastral surveys, and assesses the level of participation of the right holders and the efficiency of the current procedures. Then, a proposal for a crowdsourced general procedure with increased participation of the right holders in the initial cadastral data collection phase is designed that it may be of value either for the planners of those two projects to improve their projects towards a more fit-for-purpose approach and successfully meet the deadlines timely, or for researchers and planners of other projects with similar nation-wide approaches which also require accurate, assured and authoritative end products. For the assessment of the applicability of the proposal, three case studies are held and tested in urban, rural and suburban areas in both countries, using both a commercial application and an open source one. These crowdsourced surveys are compared to the formal cadastral surveys that have been compiled by cadastral professionals in both countries and the achieved results are assessed and judged as satisfactory in terms of geometric accuracies and the avoidance of gross errors in the location of the parcels. A proposal for future research in order to further improve the proposed procedure is discussed. |
2019 |
Gkeli, Maria; Potsiou, Chryssy; Ioannidis, Charalabos Crowdsourced 3D cadastral surveys: looking towards the next 10 years Journal Article In: Journal of Geographical Systems, vol. 21, no. 1, pp. 61-87, 2019. Abstract | Links | BibTeX | Tags: 3D cadastre, 3D modelling, Crowdsourcing, Land administration @article{Gkeli2019,Rapidly growing cities, multiple uses of urban space and the complexity of overlapping property rights require various types of rights to be registered and handled in a uniform and reliable way, considering the third dimension. The adoption of automated and low-cost but reliable procedures for cadastral surveys and for the capture and processing of cadastral data, as well as the use of modern Information Technology (IT) tools and m-services, is the beginning of a new cadastral evolution. 3D-crowdsourced cadastral data capture has huge potential and may soon facilitate the work of National Mapping Agencies (NMAs). In this paper, an innovative fit-for-purpose procedure is designed and initially tested that aims to save time and costs and to provide a modern technical solution for the initial collection, registration and visualization of 3D cadastral data. An open-source, mobile application for the acquisition of 3D crowdsourced cadastral data and 3D modelling and visualization of property units is developed, tested and presented. The proposed technical procedure is adjustable and may be used in both the developed and the developing world. The geometric accuracy of the final product depends on the geometric accuracy of the basemaps used. The developed application is tested on a multi-story building in an urban area of Larisa, in Greece. An initial evaluation of the procedure and the final product, in terms of its usability, affordability, reliability and implementation duration, is conducted. The first results are satisfactory and may lead to a fit-for-purpose procedure for a 3D cadastre for all in the future. |
2022 |
How to Improve Quality of Crowdsourced Cadastral Surveys Journal Article In: Land, vol. 11, no. 10, pp. 1642, 2022, ISSN: 2073-445X. |
2021 |
BIM data as Input to 3D Crowdsourced Cadastral Surveying-Potential and Perspectives Proceedings Article In: 2021. |
Consideration on how to introduce gamification tools to enhance citizen engagement in crowdsourced cadastral surveys Journal Article In: Surv. Rev., vol. 54, no. 383, pp. 142–152, 2021, ISSN: 0039-6265. |
2020 |
In: ISPRS Int. J. Geo-Information, vol. 9, no. 4, pp. 190, 2020, ISSN: 22209964. |
Reliable 2D Crowdsourced Cadastral Surveys: Case Studies from Greece and Romania Journal Article In: ISPRS Int. J. Geo-Information, vol. 9, no. 2, pp. 89, 2020, ISSN: 2220-9964. |
2019 |
Crowdsourced 3D cadastral surveys: looking towards the next 10 years Journal Article In: Journal of Geographical Systems, vol. 21, no. 1, pp. 61-87, 2019. |