19 research outputs found

    Towards BIM/GIS interoperability: A theoretical framework and practical generation of spaces to support infrastructure Asset Management

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    The past ten years have seen the widespread adoption of Building Information Modelling (BIM) among both the Architectural, Engineering and Construction (AEC) and the Asset Management/ Facilities Management (AM/FM) communities. This has been driven by the use of digital information to support collaborative working and a vision for more efficient reuse of data. Within this context, spatial information is either held in a Geographic Information Systems (GIS) or as Computer-Aided Design (CAD) models in a Common Data Environment (CDE). However, these being heterogeneous systems, there are inevitable interoperability issues that result in poor integration. For this thesis, the interoperability challenges were investigated within a case study to ask: Can a better understanding of the conceptual and technical challenges to the integration of BIM and GIS provide improved support for the management of asset information in the context of a major infrastructure project? Within their respective fields, the terms BIM and GIS have acquired a range of accepted meanings, that do not align well with each other. A seven-level socio-technical framework is developed to harmonise concepts in spatial information systems. This framework is used to explore the interoperability gaps that must be resolved to enable design and construction information to be joined up with operational asset information. The Crossrail GIS and BIM systems were used to investigate some of the interoperability challenges that arise during the design, construction and operation of an infrastructure asset. One particular challenge concerns a missing link between AM-based information and CAD-based geometry which hinders engineering assets from being located within the geometric model and preventing geospatial analysis. A process is developed to link these CAD-based elements with AM-based assets using defined 3D spaces to locate assets. However, other interoperability challenges must first be overcome; firstly, the extraction, transformation and loading of geometry from CAD to GIS; secondly, the creation of an explicit representation of each 3D space from the implicit enclosing geometry. This thesis develops an implementation of the watershed transform algorithm to use real-world Crossrail geometry to generate voxelated interior spaces that can then be converted into a B-Rep mesh for use in 3D GIS. The issues faced at the technical level in this case study provide insight into the differences that must also be addressed at the conceptual level. With this in mind, this thesis develops a Spatial Information System Framework to classify the nature of differences between BIM, GIS and other spatial information systems

    Modelling the world in 3D : aspects of the acquisition, processing, management and analysis of spatial 3D data

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    Output constraints in multimedia database systems

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    Zusammenfassung Semantische Fehler treten bei jeder Art von Datenverwaltung auf. Herkömmliche Datenbanksysteme verwenden eine Integritätskontrolle, um semantische Fehler zu vermeiden. Um die Integrität der Daten zu gewährleisten werden Integritätsregeln benutzt. Diese Regeln können allerdings nur die Konsistenz einfach strukturierter Daten überprüfen. Multimedia Datenbanksystem verwalten neben einfachen alphanumerischen Daten auch komplexe Mediendaten wie Videos. Um die Konsistenz dieser Daten zu sichern, bedarf es einer erheblichen Erweiterung des bestehenden Integritätskonzeptes. Dabei muss besonders auf die konsistente Datenausgabe geachtet werden. Im Gegensatz zu alphanumerischen Daten können Mediendaten während der Ausgabe verfälscht werden. Dieser Fall kann eintreten, wenn eine geforderte Datenqualität bei der Ausgabe nicht erreicht werden kann oder wenn Synchronisationsbedingungen zwischen Medienobjekten nicht eingehalten werden können. Es besteht daher die Notwendigkeit, Ouptut Constraints einzuführen. Mit ihrer Hilfe kann definiert werden, wann die Ausgabe von Mediendaten semantisch korrekt ist. Das Datenbanksystem kann diese Bedingungen überprüfen und so gewährleisten, dass der Nutzer semantisch einwandfreie Daten erhält. In dieser Arbeit werden alle Aspekte betrachtet, die notwendig sind, um Ausgabebedingungen in ein Multimedia Datenbanksystem zu integrieren. Im einzelnen werden die Modellierung der Bedingungen, deren datenbankinterne Repräsentation sowie die Bedingungsüberprüfung betrachtet. Für die Bedingungsmodellierung wird eine Constraint Language auf Basis der Prädikatenlogik eingeführt. Um die Definition von zeitlichen und räumlichen Synchronisationen zu ermöglichen, verwenden wir Allen-Relationen. Für die effiziente Überprüfung der Ausgabebedingungen müssen diese aus der Spezifikationssprache in eine datenbankinterne Darstellung überführt werden. Für die datenbankinterne Darstellung werden Difference Constraints verwendet. Diese erlauben eine sehr effiziente Bedingungsüberprüfung. Wir haben Algorithmen entwickelt, die eine effiziente Überprüfung von Ausgabebedingungen erlauben und dies anhand von Experimenten nachgewiesen. Neben der Überprüfung der Bedingungen müssen Mediendaten so synchronisiert werden, dass dies den Ausgabebedingungen entspricht. Wir haben dazu das Konzept des Output Schedules entwickelt. Dieser wird aufgrund der definierten Ausgabebedingungen generiert. Durch die Ausgabebedingungen, die in dieser Arbeit eingeführt werden, werden semantische Fehler bei der Verwaltung von Mediendaten erheblich reduziert. Die Arbeit stellt daher einen Beitrag zur qualitativen Verbesserung der Verwaltung von Mediendaten dar.Semantic errors exist as long as data are managed. Traditional database systems try to prevent this errors by proposing integrity concepts for stored data. Integrity constraints are used to implement these integrity concepts. However, integrity constraints can only detect semantic errors in elementary data. Multimedia database systems manage elementary data as well as complex media data, like videos. Considering these media data we need a much wider consistency concept as traditional database systems provide. Especially, data output of media data must be taken into account. In contrast to alphanumeric data the semantics of media data can be falsified during data output if data quality or synchronization of data are not suitable. Thus, we need a concept for output constraints that allow for preventing semantic errors in case of data output. For integrating output constraints into a multimedia database system we have to consider modelling, representation and checking of output constraints. For modelling output constraints we have introduced a constraint language which uses the same principles as traditional constraint languages. Our constraint specification language must support temporal and spatial synchronization constraints. However, it is desired to support both kinds of synchronization in almost the same manner. Therefore, we use Allen-Relations for defining temporal synchronization constraints as well as for defining spatial synchronization constraints. We need a database internal representation of output constraints that makes efficient constraint checking possible. The Allen-Relations used in the constraint language cannot be checked efficiently. However, difference constraints are a class of constraints that allows an very efficient checking. Therefore, we use difference constraints as database internal representation of output constraints. As methods for checking consistency of output constraints we use an approach based on graph theory as well as an analytical approach. Both approaches require a constraint graph as data structure. For data output we need an output order that is adequate to the defined output constraints. This output schedule can be produced based on the output constraints. With output constraints, proposed in this thesis, semantical correctness of media data considering the data output can be supported.Thus, the contribution of this work is an qualitative improvement of managing media data by database systems

    Temporal meta-model framework for Enterprise Information Systems (EIS) development

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    This thesis has developed a Temporal Meta-Model Framework for semi-automated Enterprise System Development, which can help drastically reduce the time and cost to develop, deploy and maintain Enterprise Information Systems throughout their lifecycle. It proposes that the analysis and requirements gathering can also perform the bulk of the design phase, stored and available in a suitable model which would then be capable of automated execution with the availability of a set of specific runtime components

    The building and application of a semantic platform for an e-research society

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    This thesis reviews the area of e-Research (the use of electronic infrastructure to support research) and considers how the insight gained from the development of social networking sites in the early 21st century might assist researchers in using this infrastructure. In particular it examines the myExperiment project, a website for e-Research that allows users to upload, share and annotate work flows and associated files, using a social networking framework. This Virtual Organisation (VO) supports many of the attributes required to allow a community of users to come together to build an e-Research society. The main focus of the thesis is how the emerging society that is developing out of my-Experiment could use Semantic Web technologies to provide users with a significantly richer representation of their research and research processes to better support reproducible research. One of the initial major contributions was building an ontology for myExperiment. Through this it became possible to build an API for generating and delivering this richer representation and an interface for querying it. Having this richer representation it has been possible to follow Linked Data principles to link up with other projects that have this type of representation. Doing this has allowed additional data to be provided to the user and has begun to set in context the data produced by myExperiment. The way that the myExperiment project has gone about this task and consideration of how changes may affect existing users, is another major contribution of this thesis. Adding a semantic representation to an emergent e-Research society like myExperiment,has given it the potential to provide additional applications. In particular the capability to support Research Objects, an encapsulation of a scientist's research or research process to support reproducibility. The insight gained by adding a semantic representation to myExperiment, has allowed this thesis to contribute towards the design of the architecture for these Research Objects that use similar Semantic Web technologies. The myExperiment ontology has been designed such that it can be aligned with other ontologies. Scientific Discourse, the collaborative argumentation of different claims and hypotheses, with the support of evidence from experiments, to construct, confirm or disprove theories requires the capability to represent experiments carried out in silico. This thesis discusses how, as part of the HCLS Scientific Discourse subtask group, the myExperiment ontology has begun to be aligned with other scientific discourse ontologies to provide this capability. It also compares this alignment of ontologies with the architecture for Research Objects. This thesis has also examines how myExperiment's Linked Data and that of other projects can be used in the design of novel interfaces. As a theoretical exercise, it considers how this Linked Data might be used to support a Question-Answering system, that would allow users to query myExperiment's data in a more efficient and user-friendly way. It concludes by reviewing all the steps undertaken to provide a semantic platform for an emergent e-Research society to facilitate the sharing of research and its processes to support reproducible research. It assesses their contribution to enhancing the features provided by myExperiment, as well as e-Research as a whole. It considers how the contributions provided by this thesis could be extended to produce additional tools that will allow researchers to make greater use of the rich data that is now available, in a way that enhances their research process rather than significantly changing it or adding extra workload
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