Integrity evaluation of offshore wind turbine MP-TP connection technologies

To reach net-zero emissions in the UK by 2050, in accordance with Paris agreement (2016), the imperative role of renewable energy production has become evident globally. With the exponential growth in the installed capacity of offshore wind energy in the UK and around the world, the industry is continuously increasing the capacity of wind turbines, subsequently requiring larger structures to support them. Offshore wind turbines often consist of a foundation, a transition piece, and a tower. One critical component of the offshore wind turbine structures is the connection between the Monopile (MP) foundation, which is largely employed in the majority of offshore wind turbines currently installed around the world, and the Transition Piece (TP). This thesis investigates the suitability of both current and alternative MP-TP connection technologies to provide an in-depth knowledge of the advantages and disadvantages of each technology for potential use in future offshore wind farms. In this research study Finite Element Analysis (FEA) and analytical calculations are employed to investigate three distinct MP-TP connection technologies: threaded connection, C1 wedge connection and Slip Joint technologies. Further investigations have been carried out by reanalysing the existing fatigue data on various size and threaded connections available in the literature. Furthermore, through conducting new fatigue tests, this thesis contributes a comprehensive evaluation of the accuracy of the fatigue design curves recommended in international standards for large-scale bolted connections. The findings from this study underscore the potential of the existing flanged bolted connection technology as well as two novel technologies — namely C1 connection and Slip Joint — to address current and future challenges associated with the increasing size of offshore wind turbine structures. Moreover, they highlight the need for various feasible alternative solutions for MP-TP connections to be considered and employed in future offshore wind farms. This thesis provides a comprehensive analysis of the advantages and disadvantages of the mentioned MP-TP technologies. It identifies areas for further research to address the existing gaps in knowledge and enhance understanding of these innovative technologies for deployment in future offshore wind farm projects.To reach net-zero emissions in the UK by 2050, in accordance with Paris agreement (2016), the imperative role of renewable energy production has become evident globally. With the exponential growth in the installed capacity of offshore wind energy in the UK and around the world, the industry is continuously increasing the capacity of wind turbines, subsequently requiring larger structures to support them. Offshore wind turbines often consist of a foundation, a transition piece, and a tower. One critical component of the offshore wind turbine structures is the connection between the Monopile (MP) foundation, which is largely employed in the majority of offshore wind turbines currently installed around the world, and the Transition Piece (TP). This thesis investigates the suitability of both current and alternative MP-TP connection technologies to provide an in-depth knowledge of the advantages and disadvantages of each technology for potential use in future offshore wind farms. In this research study Finite Element Analysis (FEA) and analytical calculations are employed to investigate three distinct MP-TP connection technologies: threaded connection, C1 wedge connection and Slip Joint technologies. Further investigations have been carried out by reanalysing the existing fatigue data on various size and threaded connections available in the literature. Furthermore, through conducting new fatigue tests, this thesis contributes a comprehensive evaluation of the accuracy of the fatigue design curves recommended in international standards for large-scale bolted connections. The findings from this study underscore the potential of the existing flanged bolted connection technology as well as two novel technologies — namely C1 connection and Slip Joint — to address current and future challenges associated with the increasing size of offshore wind turbine structures. Moreover, they highlight the need for various feasible alternative solutions for MP-TP connections to be considered and employed in future offshore wind farms. This thesis provides a comprehensive analysis of the advantages and disadvantages of the mentioned MP-TP technologies. It identifies areas for further research to address the existing gaps in knowledge and enhance understanding of these innovative technologies for deployment in future offshore wind farm projects

Critical analysis of MP-TP wedge connection concept for application in offshore wind turbines

The main technologies that have been employed in the offshore wind industry for connecting the monopile foundation to the transition piece (MP-TP) are the grouted connection and threaded connection. The latter has been widely used in the majority of offshore wind farms developed in the last decade. However, as the offshore wind turbines get larger in size to increase the level of produced electricity, there is an essential need to re-evaluate the use of threaded joints as the current main choice for MP-TP connections and develop new MP-TP concepts which offer lower costs. An innovative MP-TP technology which has been developed for application in offshore wind industry is the wedge connection concept. In this paper, an independent study has been conducted through analytical evaluation and finite element analysis to understand the technological benefits that this concept offers. The study has been developed in three different steps: design of hole geometry, stress distribution prediction and a real-case scenario to evaluate the strength of the system under different loading conditions. The results from this study have been discussed in terms of the main advantages that the wedge connection technology offers as an alternative MP-TP concept for offshore wind applications

Fatigue life analysis of threaded connections in offshore wind turbines

With the rapid expansion of the installed offshore wind capacity around the world, it is essential to improve the structural integrity of these energy structures for reduced electricity cost and prolonged operational lifespans. An important part of the offshore wind turbine structures is the connection between the monopile foundation and the transition piece. Currently the dominant technology for connecting the monopile to transition piece is using L flanges held together with large-scale bolts. Threaded connections have emerged as a prevalent technology for linking sections of wind turbines, boasting commendable performance despite some inherent drawbacks. This study conducts a comprehensive review of the recommended fatigue design curves for threaded connections in international standards and compares them with the existing fatigue data on medium to large scale bolt sizes. Additionally, the fatigue behaviour of M72 threaded connections has been further analysed by performing new tests with two different values of mean stress. The obtained data from this study have been discussed in terms of the level of conservatism in the recommended fatigue design curves available in international standards for threaded connections. Moreover, the experimental analysis has been combined with numerical and analytical investigations to provide further insight into the life prediction of the threaded connections under fatigue loading conditions

Optimising design parameters for offshore wind MP-TP wedge connection technology using analytical techniques

The offshore wind industry is a rapidly growing sector and will likely play a significant role in the future of green energy. Monopile support structures are the dominant foundation type in offshore wind turbines. Existing monopile to transition piece technologies have a number of challenges, and a new design, called wedge connection, presents a promising solution. In the present study analytical techniques, supported with finite element modelling, have been used to optimise the wedge connection design. A spring model was created and solved for both the application of the preload and the combination of the preload and the external force. A lower bound on the preload that would ensure the connection does not become loose was found. The self-locking mechanism was shown to be not a required design feature. The optimum number of wedge connections in one offshore wind turbine has been found as a function of the width of the connection and the monopile diameter. It has been shown that laboratory experiments on a single segment of wedge connection are likely to be conservative due to a higher stress concentration factor than in the full structure

Neurocognitive Impairment in HIV-Infected Naïve Patients with Advanced Disease: The Role of Virus and Intrathecal Immune Activation

Objective. To investigate intrathecal immune activation parameters and HIV-RNA in HIV-associated neurocognitive disorders (HAND) of advanced naïve HIV-infected patients and to evaluate their dynamics before and after initiation of antiretroviral therapy (ART). Methods. Cross-sectional and longitudinal analysis of HIV RNA, proinflammatory cytokines (IL-6, IL-10, INF-γ, TNF-α, TGF-β1, and TGF-β2) and chemokines (MIP-1α, MIP-1β, and MCP-1) in plasma and cerebrospinal fluid (CSF) of HIV-infected patients with CD4 <200/μL. Results. HAND was diagnosed at baseline in 6/12 patients. Baseline CSF HIV-RNA was comparable in patients with or without HAND, whereas CSF concentration of IL-6 and MIP-1β, proinflammatory cytokines, was increased in HAND patients. CSF evaluation at 12 weeks was available in 10/12 cases. ART greatly reduced HIV-RNA in all patients. Nevertheless, IL-6 and MIP-1β remained elevated after 12 weeks of therapy in HAND patients, in whom CSF HIV RNA decay was slower than the plasmatic one as well. Conclusion. Immune activation, as indicated by inflammatory cytokines, but not higher levels of HIV-RNA is observed in advanced naïve HIV-infected patients with HAND. In HAND patients, ART introduction resulted in a less rapid clearance of CSF viremia compared to plasma and no modifications of intratechal immune activation

Digital earth:yesterday, today, and tomorrow

The concept of Digital Earth (DE) was formalized by Al Gore in 1998. At that time the technologies needed for its implementation were in an embryonic stage and the concept was quite visionary. Since then digital technologies have progressed significantly and their speed and pervasiveness have generated and are still causing the digital transformation of our society. This creates new opportunities and challenges for the realization of DE. ‘What is DE today?’, ‘What could DE be in the future?’, and ‘What is needed to make DE a reality?’. To answer these questions it is necessary to examine DE considering all the technological, scientific, social, and economic aspects, but also bearing in mind the principles that inspired its formulation. By understanding the lessons learned from the past, it becomes possible to identify the remaining scientific and technological challenges, and the actions needed to achieve the ultimate goal of a ‘Digital Earth for all’. This article reviews the evolution of the DE vision and its multiple definitions, illustrates what has been achieved so far, explains the impact of digital transformation, illustrates the new vision, and concludes with possible future scenarios and recommended actions to facilitate full DE implementation.</p

JRC Data Policy

The work on the JRC Data Policy followed the task identified in the JRC Management Plan 2014 to develop a dedicated data policy to complement the JRC Policy on Open Access to Scientific Publications and Supporting Guidance, and to promote open access to research data in the context of Horizon 2020. Important policy commitments and the relevant regulatory basis within the European Union and the European Commission include: the Commission Decision on the reuse of Commission documents, Commission communication on better access to scientific information, Commission communication on a reinforced European research area partnership for excellence and growth, Commission recommendation on access to and preservation of scientific information, and the EU implementation of the G8 Open Data Charter.JRC.H.6-Digital Earth and Reference Dat

Next-Generation Digital Earth: A position paper from the Vespucci Initiative for the Advancement of Geographic Information Science

This position paper is the outcome of a joint reflection by a group of international geographic and environmental scientists from government, industry, and academia brought together by the Vespucci Initiative for the Advancement of Geographic Information Science, and the Joint Research Centre of the European Commission. It argues that the vision of Digital Earth put forward by Vice-President Al Gore 10 years ago needs to be re-evaluated in the light of the many developments in the fields of information technology, data infrastructures, and earth observation that have taken place since. It focuses the vision on the next-generation Digital Earth and identifies priority research areas to support this vision. The paper is offered as input for discussion among different stakeholder communities with the aim to shape research and policy over the next 5-10 years

PIXAPP Photonics Packaging Pilot Line development of a silicon photonic optical transceiver with pluggable fiber connectivity

This paper demonstrates how the PIXAPP Photonics Packaging Pilot Line uses its extensive packaging capabilities across its European partner network to design and assemble a highly integrated silicon photonic-based optical transceiver. The processes used are based on PIXAPP's open access packaging design rules or Assembly Design Kit (ADK). The transceiver was designed to have the Tx and Rx elements integrated on to a single silicon photonic chip, together with flipchip control electronics, hybrid laser and micro-optics. The transceiver used the on-chip micro-optics to enable a pluggable fiber connection, avoiding the need to bond optical fibers directly to the photonic chip. Finally, the packaged transceiver module was tested, showing 56 Gb/s loop-back modulation and de-modulation, validating both the transmitter and receiver performance

Artificial Intelligence: A European Perspective

We are only at the beginning of a rapid period of transformation of our economy and society due to the convergence of many digital technologies. Artificial Intelligence (AI) is central to this change and offers major opportunities to improve our lives. The recent developments in AI are the result of increased processing power, improvements in algorithms and the exponential growth in the volume and variety of digital data. Many applications of AI have started entering into our every-day lives, from machine translations, to image recognition, and music generation, and are increasingly deployed in industry, government, and commerce. Connected and autonomous vehicles, and AI-supported medical diagnostics are areas of application that will soon be commonplace. There is strong global competition on AI among the US, China, and Europe. The US leads for now but China is catching up fast and aims to lead by 2030. For the EU, it is not so much a question of winning or losing a race but of finding the way of embracing the opportunities offered by AI in a way that is human-centred, ethical, secure, and true to our core values. The EU Member States and the European Commission are developing coordinated national and European strategies, recognising that only together we can succeed. We can build on our areas of strength including excellent research, leadership in some industrial sectors like automotive and robotics, a solid legal and regulatory framework, and very rich cultural diversity also at regional and sub-regional levels. It is generally recognised that AI can flourish only if supported by a robust computing infrastructure and good quality data: • With respect to computing, we identified a window of opportunity for Europe to invest in the emerging new paradigm of computing distributed towards the edges of the network, in addition to centralised facilities. This will support also the future deployment of 5G and the Internet of Things. • With respect to data, we argue in favour of learning from successful Internet companies, opening access to data and developing interactivity with the users rather than just broadcasting data. In this way, we can develop ecosystems of public administrations, firms, and civil society enriching the data to make it fit for AI applications responding to European needs. We should embrace the opportunities afforded by AI but not uncritically. The black box characteristics of most leading AI techniques make them opaque even to specialists. AI systems are currently limited to narrow and well-defined tasks, and their technologies inherit imperfections from their human creators, such as the well-recognised bias effect present in data. We should challenge the shortcomings of AI and work towards strong evaluation strategies, transparent and reliable systems, and good human-AI interactions. Ethical and secure-by-design algorithms are crucial to build trust in this disruptive technology, but we also need a broader engagement of civil society on the values to be embedded in AI and the directions for future development. This social engagement should be part of the effort to strengthen our resilience at all levels from local, to national and European, across institutions, industry and civil society. Developing local ecosystems of skills, computing, data, and applications can foster the engagement of local communities, respond to their needs, harness local creativity and knowledge, and build a human-centred, diverse, and socially driven AI. We still know very little about how AI will impact the way we think, make decisions, relate to each other, and how it will affect our jobs. This uncertainty can be a source of concern but is also a sign of opportunity. The future is not yet written. We can shape it based on our collective vision of what future we would like to have. But we need to act together and act fast.JRC.B.6-Digital Econom