1,720,986 research outputs found
Enabling a fully integrated BIM environment using Semantics and Artificial Intelligence
Get PDFThis thesis addresses the challenge of data fragmentation in the Architecture, Engineering, Construction, and Operations industry by proposing an integrated framework that combines semantic web technologies and artificial intelligence. Despite the impact of Building Information Modelling in transforming traditional design and construction workflows, the full potential of Building Information Modelling remains limited by the isolation of data across multiple platforms and disciplines. Traditional Computer-Aided Design and early Building Information Modelling systems often rely on visual integration, which lacks the robust semantic connections needed for automated data exchange and cross-disciplinary validation.
The research is organised into three interrelated branches. The first branch focuses on the federation of Building Information Modelling models by converting disparate domain-specific representations into a unified semantic framework. By transforming files based on Industry Foundation Classes into ontological formats, the study identifies and links duplicated elements, such as spatial zones and building storeys, across different models. This process establishes explicit semantic relationships that overcome the limitations of mere visual coordination, enabling a more integrated and machine-readable data environment. The creation of these semantic links not only enhances interoperability but also lays the groundwork for automated reasoning and efficient information retrieval across disciplines.
The second branch introduces novel artificial intelligence methods for the automated validation of Building Information Modelling content. Recognising that manual verification is both error-prone and resource-intensive, the thesis employs deep learning approaches, including graph neural networks and context-aware neural networks, to systematically identify and correct inconsistencies in element classification and property definitions. These artificial intelligence-driven models are trained on publicly available open-source Building Information Modelling datasets, which serve as proxies for real-world applications. The experimental results demonstrate significant improvements in the accuracy and reliability of automated data validation processes. By reducing dependency on manual checks, the proposed methods substantially mitigate risks associated with misclassification and erroneous data entries, thereby enhancing overall model integrity.
The third branch extends the framework by integrating external data sources for cross-validation. Crucial information that is often relevant to a building project, such as schematic drawings, design documents, or ancillary databases, is not embedded within the Building Information Modelling model itself. To address this gap, a conceptual framework is developed to extract, structure, and compare external information with the Building Information Modelling content. This cross-validation process ensures that discrepancies between the digital model and real-world documentation are detected early, allowing for timely corrections that improve project outcomes. Such a systematic approach not only fortifies the reliability of Building Information Modelling data but also supports advanced applications such as digital twin implementations and intelligent asset management.
Overall, the contributions of this thesis offer a robust pathway toward mitigating data fragmentation in the Architecture, Engineering, Construction, and Operations industry. By establishing a fully integrated Building Information Modelling environment through semantic enrichment and artificial intelligence-based validation, the proposed framework enhances the fidelity of digital models and streamlines interdisciplinary collaboration. The research results present that automated semantic integration and data validation can significantly increase operational efficiency and data quality in construction projects. Future research will focus on further improvement of proposed artificial intelligence methodologies and expanding the framework to adapt to evolving industry standards and new technological innovations, ultimately providing the way for smarter, more firm construction environments.In reference to IEEE copyrighted material which is used with permission in this thesis, the IEEE does not endorse any of NTNU’s products or services. Internal or personal use of this material is permitted. If interested in reprinting/republishing IEEE copyrighted material for advertising or promotional purposes or for creating new collective works for resale or redistribution, please go to http://www.ieee.org/publications_standards/publications/rights/rights_link.html to learn how to obtain a License from RightsLink
Competitive timber floors Optimisation of hollow section timber floor elements for adaptable buildings
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Competitive timber floors Optimisation of hollow section timber floor elements for adaptable buildings
No full textGoing Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
AI-driven sustainable cities: A Nordic-inspired requirement framework
Get PDFThis paper examines the integration of AI and data technologies into sustainable urban development, emphasizing Norway's unique cultural and environmental context. It first explores how concepts like trust and sustainability inform urban planning and operations. Then, the study assesses AI's potential to enhance urban development, and, through case studies, it identifies challenges and opportunities in adopting these technologies. Finally, it proposes a Nordic requirement framework for AI and data integration, promoting sustainability aligned with Norway's values and adaptable for broader European contexts
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Damping in Timber Structures
Get PDFKey point to development of environmentally friendly timber structures, appropriate to urban ways of living, is the development of high-rise timber buildings. Comfort properties are nowadays one of the main limitations to tall timber buildings, and an enhanced knowledge on damping phenomena is therefore required, as well as improved prediction models for damping.
The aim of this work has consequently been to estimate various damping quantities in timber structures. In particular, models have been derived for predicting material damping in timber members, beams or panels, or in more complex timber structures, such as floors. Material damping is defined as damping due to intrinsic material properties, and used to be referred to as internal friction. In addition, structural damping, defined as damping due to connections and friction in-between members, has been estimated for timber floors.
The thesis consists of six main parts. The first part is entitled “Contexts”, and is composed of four chapters. A general overview of the wood material and its structural use in buildings is presented in Chapter 1. Chapter 2 gives a thorough literature review on comfort properties of (timber) floors. Chapter 1 and Chapter 2 serve as justifications for the motivation of this work, expressed in Chapter 3, and the aim of the work, expressed in Chapter 4.
The next part “Backgrounds” briefly describes the basic theories used along the thesis, for the analytical studies (Chapter 5), the experimental studies (Chapter 6), and the numerical studies (Chapter 7). The part “State of the art” is a general literature review on damping (Chapter 8). A particular accent is set on the derivation of various damping prediction models.
The “Research” part summarizes the original research work. Chapter 9 briefly presents the background and main findings for each study, and Chapter 10 concludes and proposes suggestions for further research.
The studies are detailed in four journal papers, which are integrally reported in the “Publications” part.
Paper I focuses on the evaluation of material damping in timber beam specimens with dimensions typical of common timber floor structures. Using the impact test method, 11 solid wood beams and 11 glulam beams made out of Norway Spruce (Picea Abies) were subjected to flexural vibrations. The tests involved different spans and orientations. A total of 420 material damping evaluations were performed, and the results are presented as mean values for each configuration along with important statistical indicators to quantify their reliability. The consistency of the experimental method was validated with respect to repeatability and reproducibility. General trends found an increasing damping ratio for higher modes, shorter spans, and edgewise orientations. It is concluded from the results that material damping is governed by shear deformation, which can be expressed more conveniently with respect to the specific mode shape and its derivatives.
Paper II deals with the prediction of material damping in Timoshenko beams. Complex elastic moduli and complex stiffness are defined to derive an analytical model that predicts the hysteretic system damping for the whole member. The prediction model comprises two parts, the first related to bending, and the second related to shear. Selected experimental damping evaluations from Paper I are used to validate the model and obtain fitted values of loss factors for two types of wood. The good agreement of the derived model with experimental data reveals an efficient approach in the prediction of material damping.
In Paper III, a semi-analytical prediction model of material damping in timber panels is described. The approach is derived from the strain energy method and input is based on loss factors, which are intrinsic properties of the considered materials, together with material properties and mode shape integrals, whose calculation can easily be implemented in most finite element codes. Experimental damping evaluations of three types of timber panels are performed. These are particleboards, oriented strand board panels and structural laminated veneer panels. Fair goodness-of-fit between the experimental results and the prediction models reveals an efficient approach for the prediction of material damping in timber panels with any boundary conditions, knowing only the loss factors and the mode shapes.
In Paper IV, dynamic properties of two timber floors are experimentally evaluated by impact method. Each floor uses one specified type of connectors, either screws or nails. A numerical model is developed using constrained degrees-of-freedom for the modeling of connectors. Numerical analyses have been performed, and show good agreement with experimental results. A procedure is written using the commercial finite element software Abaqus to predict material damping from a strain energy approach. Estimation of structural damping is performed as the difference between the experimentally evaluated total damping and the predicted material damping. The contribution from floor members to material damping is extensively investigated, and the needs for better prediction of damping are discussed.
Specific details of some aspects of the work are included in the “Appendix” part.PhD i konstruksjonsteknikkPhD in Structural Engineerin
Stormwater-related databases – Review and Recommendations
Get PDFFloods and stormwater events are the costliest natural catastrophes. Costs are expected to increase due to urbanization and climate change. Mitigation is needed, and is already ongoing in certain cases. Different stakeholders with different motivations unfortunately often evaluate vulnerability by using fragmented and incomplete data sources. This report intends to review the different approaches for collecting and analysing data, and to evaluate their usefulness within the proposed framework for a "smart" use of data. The objectives of this work have been: - to describe a selection of event-based databases related to floods, - to review qualitatively and quantitatively a selection of national object-based databases, - to evaluate the current Norwegian situation and to propose measures for improvement. This study has shown that data are spread around a heterogeneous community of stakeholders concerned with different motivations, different needs, and different levels of data processing. In general, the needs of the different stakeholders have not been surveyed and defined systematically enough. Regarding international flood databases, there is still a substantial demand for a standardized and systematic collection of flood damage data with clearly defined and documented procedures. Regarding national stormwater-related inventory databases, there is a substantial potential in upgrading from the delivery of passive raw data to the delivery of knowledge-driven decision-support tools. Further work should aim at: ‐ Exploiting more efficiently available sources of data and exploring alternative sources of data,‐ Achieving a more efficient transformation of data into knowledge via the development of analytical tools that match the identified needs of relevant end-users by efficiently processing several relevant sources of data, ‐ Providing ergonomic and user-friendly digital solutions to support workers in their daily tasks and to efficiently document the actions within the system, and ‐ Triggering the implementation of evaluation processes within the national agencies for business purposes, and at a national scale for providing the policymakers with useful knowledge about the societal risks associated with climate changes. Technical challenges can relatively easily be solved by digitization and its opportunities for improvement of the workflow and for higher quality of data. Organisational challenges must be solved by an end-users-focused approach to identify needs and expectations. The task WP2.1 intends to be a catalyser within Klima 2050 project for triggering a global data-driven evaluation system to provide policymakers with knowledge on societal risk associated with climate change, and for strengthening national agencies and private companies' innovation capacity for addressing climatic changes.publishedVersio
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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