Infrastructure Engineering - Research Publications
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ItemAssessment of relative accuracy of AHN-2 laser scanning data using planar features(MDPI, 2010)AHN-2 is the second part of the Actueel Hoogtebestand Nederland project, which concerns the acquisition of high-resolution altimetry data over the entire Netherlands using airborne laser scanning. The accuracy assessment of laser altimetry data usually relies on comparing corresponding tie elements, often points or lines, in the overlapping strips. This paper proposes a new approach to strip adjustment and accuracy assessment of AHN-2 data by using planar features. In the proposed approach a transformation is estimated between two overlapping strips by minimizing the distances between points in one strip and their corresponding planes in the other. The planes and the corresponding points are extracted in an automated segmentation process. The point-to-plane distances are used as observables in an estimation model, whereby the parameters of a transformation between the two strips and their associated quality measures are estimated. We demonstrate the performance of the method for the accuracy assessment of the AHN-2 dataset over Zeeland province of The Netherlands. The results show vertical offsets of up to 4 cm between the overlapping strips, and horizontal offsets ranging from 2 cm to 34 cm.
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ItemContribution of typical non-structural components to the performance of high-rise buildings based on field reconnaissance(Springer Science and Business Media LLC, 2010-09-01)
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ItemDevelopment of an interoperable tool to facilitate spatial data integration in the context of SDI(Taylor & Francis, 2010)The integration of multisource heterogeneous spatial data is one of the major challenges for many spatial data users. To facilitate multisource spatial data integration, many initiatives including federated databases, feature manipulation engines (FMEs), ontology-driven data integration and spatial mediators have been proposed. The major aim of these initiatives is to harmonize data sets and establish interoperability between different data sources. On the contrary, spatial data integration and interoperability is not a pure technical exercise, and there are other nontechnical issues including institutional, policy, legal and social issues involved. Spatial Data Infrastructure (SDI) framework aims to better address the technical and nontechnical issues and facilitate data integration. The SDIs aim to provide a holistic platform for users to interact with spatial data through technical and nontechnical tools. This article aims to discuss the complexity of the challenges associated with data integration and propose a tool that facilitates data harmonization through the assessment of multisource spatial data sets against many measures. The measures represent harmonization criteria and are defined based on the requirement of the respective jurisdiction. Information on technical and nontechnical characteristics of spatial data sets is extracted to form metadata and actual data. Then the tool evaluates the characteristics against measures and identifies the items of inconsistency. The tool also proposes available manipulation tools or guidelines to overcome inconsistencies among data sets. The tool can assist practitioners and organizations to avoid the time-consuming and costly process of validating data sets for effective data integration.
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ItemA better way to manage land information(The Intermedia Group, 2010)Australia’s Federal Government has no constitutional authority over land administration. Each state and territory has its own system and, to date, this system has served the nation well. Each system is reflected in the historic, independent pattern where each jurisdiction computerises its own processes and operates according to its own timetable, needs, reporting functions, customer service design and other imperatives. However, the country’s capacity to meet increasingly national issues – such as management of the macro economy, a national property market, climate change response, disaster management, national business coordination and national security– is problematic. Seamless information about landownership, and its use, value and development is essential to the strategic planning of capital cities. Processes such as levying capital gains tax, allocating drought relief, and managing crime and terrorism all require broad strategic planning, as do the development of early warning systems for emergencies and climate change initiatives. As a consequence, national priorities that rely on information about land are faced with the technical, policy and institutional barriers that come with integrating data from multiple state-based sources. The solution is a national land information infrastructure.