A qualitive reasoning approach for improving query results for sketch based queries by topological analysis of spatial aggregation

Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.Sketch-based spatial query systems provide an intuitive method of user interaction for spatial databases. These systems must be capable of interpreting user sketches in a way that matches the information that the user intended to provide. One challenge that must be overcome is that humans always simplify the environments they have experienced and this is reflected in the sketches they draw. One such simplification is manifested as aggregation or combination of spatial objects into conceptually or spatially related groups. In this thesis I develop a system that uses reasoning tools of the RCC-8 to evaluate sketchbased queries and provide a method for minimizing the effects of aggregation by determining whether a solution to a query can be expanded if some groups of regions are assumed to be parts of a larger aggregate region. If such a group of regions is found, then this group must be included in the solution. The solution is approximate because the approach taken only verifies that assumed parts of an aggregate are not inconsistent with the configuration of the whole solution. Only cases where the size of the solution equals the size of the query minus one are analysed. It is observed that correctly identifying aggregated regions leads to solutions that are more similar to the original query sketch when the size of every other solution is smaller than the size of the query or when a lower limit is placed on the acceptable size of a solution because the new, expanded or refined solution becomes more complete with respect to the sketch of the query

Cognitively plausible representations for the alignment of sketch and geo-referenced maps

In many geo-spatial applications, freehand sketch maps are considered as an intuitive way to collect user-generated spatial information. The task of automatically mapping information from such hand-drawn sketch maps to geo-referenced maps is known as the alignment task. Researchers have proposed various qualitative representations to capture distorted and generalized spatial information in sketch maps, however thus far the effectiveness of these representations has not been evaluated in the context of an alignment task. This paper empirically evaluates a set of cognitively plausible representations for alignment using real sketch maps collected from two different study areas with the corresponding geo-referenced maps. Firstly, the representations are evaluated in a single-aspect alignment approach by demonstrating the alignment of maps for each individual sketch aspect. Secondly, representations are evaluated across multiple sketch aspects using more than one representation in the alignment task. The evaluations demonstrated the suitability of the chosen representation for aligning user-generated content with geo-referenced maps in a real-world scenario

Navigating the Terrain of Digital Transition: Ghana’s Journey of Developing a Digital Land Information System

This paper explores Ghana’s two-decade journey in developing a digital land information system (LIS), exemplified by Ghana Enterprise Land Information System (GELIS) and Enterprise Land Information System (ELIS). Despite advancements by Ghana’s Lands Commission, manual processes persist and coexist with digital ones. Our study uses a qualitative approach to assess the effectiveness of the LIS implemented in Accra. This study found that Accra’s LIS is highly aligned with clear institutional mandates, roles, and responsibilities, as well as the availability of laws and policies to support analogue-to-digital conversion. Furthermore, a robust approach to protecting the data, operating system, and software underpins the system. Subsequently, the integration of a digital LIS has enhanced service delivery and accountability. Nonetheless, Accra’s LIS is still at the beginning of a comprehensive learning and development curve. Sustaining the LIS requires furtherance in the implementation plan, funding, law implementation, ICT strategy, divisional integration, work processes, data quality, and communication strategy. These findings will inform the next steps of improvement for Accra’s LIS and guide its nationwide scaling, contributing to discussions on technology acceptance dynamics in predominantly analogue environments

Deriving requirements for integrated and standardised cadastre profile from the legacy Board of Revenue and the contemporary land administration systems

Modernising the paper-based manual Land Administration System (LAS) benefits society at large. This study examines the integration and standardisation requirements of LASs in Islamabad, Pakistan, using the Land Administration Domain Model (LADM). The exploratory case study approach assesses land tenure, value, use and development aspects. The existing LASs satisfy LADM requirements for a unified LAS. Systematic transformations are required to upgrade revenue sketch maps and drawings into accurate geospatial data in 2D and above and below-ground infrastructure into 3D. Developing a LADM edition I & II country profile is recommended for land tenure security, socioeconomic development and sustainable urban growth

Applying the Land Administration Domain Model (LADM) for Integrated, Standardized, and Sustainable Development of Cadastre Country Profile for Pakistan

Rapid urban growth necessitates focused attention regarding its policy and governance to ensure affordable housing, transparent and efficient real-world systems, reduce social inequalities, and promote sustainable development. This study delves into the semantics and ontology for developing a Land Administration Domain Model (LADM) profile in the context of Pakistan’s Land Administration Systems (LASs), which currently face issues due to manual record-keeping, lack of transparency, frauds, and disintegration. Establishing a baseline through Record of Rights (RoR) and Property Information Report (PIR), alongside surveying and mapping procedures defined by laws and rules, forms the foundation for LADM profile development. This study explores the transition from manual LAS to 2D/3D representation, using LADM as a conceptual guideline. The LADM profile’s three key packages—PK_Party, PK_Administrative, and PK_SpatialUnit—a sub-package, and external classes are examined, with proposals for digitalisation and modernisation. Additionally, the study includes expert consultation, and highlights the significant support that the LADM implementation offers to achieve Sustainable Development Goals (SDGs) in Pakistan. In conclusion, the study underscores the need for a comprehensive and inclusive approach to address organisational overlaps and ambiguities within LAS, positioning PK LADM as a transformative force for sustainable urban LAS in Pakistan, aligning with broader SDGs. Recommendations include exploring realistic land valuation, integrated ownership and location verification systems, addressing historical survey data challenges, and promoting wider stakeholder adoption for sustainable 2D/3D urban LAS using LADM and its edition II as a way forward towards the creation of a smart city and digital twin

Cognitively plausible representations for the alignment of sketch and geo-referenced maps

In many geo-spatial applications, freehand sketch maps are considered as an intuitive way to collect user-generated spatial information. The task of automatically mapping information from such hand-drawn sketch maps to geo-referenced maps is known as the alignment task. Researchers have proposed various qualitative representations to capture distorted and generalized spatial information in sketch maps, however thus far the effectiveness of these representations has not been evaluated in the context of an alignment task. This paper empirically evaluates a set of cognitively plausible representations for alignment using real sketch maps collected from two different study areas with the corresponding geo-referenced maps. Firstly, the representations are evaluated in a single-aspect alignment approach by demonstrating the alignment of maps for each individual sketch aspect. Secondly, representations are evaluated across multiple sketch aspects using more than one representation in the alignment task. The evaluations demonstrated the suitability of the chosen representation for aligning user-generated content with geo-referenced maps in a real-world scenario