Search Results (15)

The advancement of floating offshore wind energy demands innovative and robust mooring and shared infrastructure solutions to enable scalable, cost-effective deployment of future wind farms. This review provides a comprehensive overview of shared mooring systems for floating offshore wind applications, with a focus on system configurations, environmental load considerations, modelling methods and mooring cost estimations. Existing concepts of shared mooring and shared anchoring are summarized and discussed. Drawing on insights from numerical studies, industrial practices, and academic research, the paper identifies key technical challenges and gaps in current design methodologies, validation requirements, and regulatory frameworks. Recommendations are proposed to guide future research aimed at improving system reliability, optimizing mooring layouts, and lowering the levelized cost of energy for large-scale floating wind projects. Full article

This study explores the factors driving employees’ sustainability-switching behaviors (SSBs) by integrating the Push, Pull, and Mooring (PPM) model with the Theory of Reasoned Action (TRA). A quantitative, cross-sectional survey was conducted with a convenience sample of 132 professionals actively involved in organizational sustainability initiatives across diverse industries and global regions. The findings reveal that leadership commitment significantly fosters both affective and normative employee commitments, with normative commitment positively influencing SSB. Surprisingly, organizational trust showed a negative impact on SSB, suggesting that employees may delegate responsibility for sustainability to the organization when trust is high. Inertia emerged as a strong barrier to behavioral change, independently inhibiting sustainability efforts. The study highlights the complex dynamics among leadership, trust, and inertia, offering practical insights for organizations aiming to foster sustainability. Addressing inertia directly and promoting shared responsibility for sustainability are critical for successful organizational transitions. Future research should explore the psychological mechanisms behind inertia and further investigate the paradoxical role of trust in sustainability initiatives. Full article

As design options for floating wind farms continue to be explored, shared (or multiline) anchors that secure mooring lines from multiple turbines remain a promising technology that can potentially reduce the number of anchors and overall mooring costs. This study evaluates two methods for analyzing the loads on shared anchors: one in which floating offshore wind turbines are simulated individually (using the software OpenFAST), and one in which an entire floating wind farm is simulated collectively (using the software FAST.Farm). A three-line shared anchor is evaluated for multiple loading scenarios in deep water, using the International Energy Agency 15 MW turbine on the VolturnUS-S semisubmersible platform. While the two methods produce broadly comparable results, the coupled wave loading on platforms within the farm results in wave force cancellations and amplifications that decrease multiline force directional ranges and increase multiline force extreme values (up to 7%) and standard deviations (up to 11%) for wave-driven load cases. The inclusion of wakes in FAST.Farm also reduces the net load on the shared anchor due to the velocity deficit, leading to larger differences between OpenFAST and FAST.Farm (up to 3% difference in mean loads) for load cases with operational turbines. Full article

Poetry and philosophy have had a close but uneasy relationship in the western tradition. Both share an eschewal of the discovery of novel facts, but are somewhat opposed in that discovery is a central aim of poetry, but not at all the aim of philosophy. Through a close reading of W.H. Auden’s ‘In Memory of W.B. Yeats’ and a versification of part of G.E. Moore’s ‘A Defence of Common Sense’, I argue that what poetry shows corresponds, in a broadly symbolist sense, to Wittgenstein’s understanding of the miraculous nature of the world. In this regard, poetry can offer philosophy clarity, in the form of its tonal architecture, value, and ethics, and may also constitute a perspicuous representation. Poetry remains in a perpetual mode of potential, as well as being possessed of a vatic autonomy. Full article

This paper presents a generalized and efficient method for quasi-static analysis of mooring systems, including complex scenarios such as when shared mooring lines interconnect multiple floating wind or wave energy devices. While quasi-static mooring models are well established, most published formulations are focused on specific applications, and no publicly available implementations provide efficient handling of large mooring system networks. The present formulation addresses these gaps by: (1) formulating solutions for edge cases not typically supported by quasi-static models; (2) creating a fully generalized model structure such that any combination of mooring lines, point masses, and floating bodies can be assembled; and (3) deriving analytic expressions for the system Jacobians (stiffness matrices) so that systems with many degrees of freedom can be solved efficiently. These techniques form the theory basis of MoorPy, an open-source mooring analysis library. The model is demonstrated on nine scenarios of increasing complexity with features of interest for offshore renewable energy applications. When compared with steady-state results from a lumped-mass dynamic model, the results show that the quasi-static formulation accurately calculates profiles and tensions and that its analytic approach provides more efficient and reliable computation of system stiffness matrices than finite-differencing methods. These results verify the accuracy of the MoorPy model. Full article

Compressors are an essential component of aircraft engines. Their design and operation must be extremely reliable as engine safety and performance depend greatly on these elements. Axial compressors exhibit instabilities, such as surge or rotating stall, in a region close to the peak of their performance curves. These fluid dynamic instabilities can cause drops in efficiency, stress on the blades, fatigue, and even failures. Compressors are handled therefore by operating with a safety margin far from the surge line. Moreover, models able to predict onset instabilities and to reproduce them are of great interest. A dynamic system able to describe successfully both surge and rotating stall is the model presented by Moore and Greitzer That model has also been used for developing control laws of the compressor dynamics. The present work aims at developing an artificial neural network (ANN) approach able to predict either the permanence of the system in stable working condition or the onset instabilities from a time sequence of the compressor dynamics. Different solutions were tried to find the most suitable model for identifying the system, as well as the effects of the duration of the time sequence on the accuracy of the predicted compressor working conditions. The network was further tried for sequences with different initial values in order to perform a system analysis that included multiple variations from the initial database. The results show how it is possible to identify with high accuracy both rotating stall and surge with the ANN approach. Moreover, the presence of an underlying fluid dynamic model shares some similarities with physically informed AI procedures. Full article

This study investigated the interplay between exit selection models and local pedestrian movement patterns within floor field frameworks. Specifically, this investigation analysed the performance of a multinomial logit exit choice model, incorporating both expected utility theory and cumulative prospect theory frameworks when coupled with three distinct local-level pedestrian movement models (FF-Von Neumann, FF-Moore, and NSFF). The expected utility theory framework considers the deterministic component as a linear relationship, while the cumulative prospect theory framework further considers the decision-maker’s risky attitudes by transforming objective terms into subjective terms using a power value function. The core objective was to comprehend how local movement dynamics, as represented by the floor field models, influence decision-making during exit selection. Comparative analyses revealed intriguing variations between the three local models, despite their shared expected utility theory-based exit choice framework. These discrepancies stemmed from the diverse pedestrian trajectory behaviours generated by each model. Consequently, these local dynamics impacted the decision-maker’s assessment of critical factors, such as the number of evacuees close to the decision-maker ($NCDM$) and the number of evacuees close to an exit ($NCE$), which the exit choice model incorporates. These assessments, in turn, significantly affected higher-level decision-making. The integration of the three models with the multinomial logit exit choice model, using either cumulative prospect theory and expected utility theory frameworks, further strengthened the observed bilateral relationship. While the specific nature of this relationship varied depending on the chosen framework and its implementation details, these consistent findings demonstrate the robustness of the results. This reinforced the influence of local-level pedestrian dynamics on higher-level exit selection, highlighting the importance of accurate crowd dynamics modelling, especially when advanced exit choice models consider local movement factors. Full article

This study predicted the motion response and power performance of a floating wind turbine system equipped with a semisubmersible Taida platform, an IEA 15 MW wind turbine, and a 3 × 2 mooring design in the Hsinchu offshore area in the Taiwan Strait. The hydrodynamic properties were calculated using ANSYS-AQWA and STAR-CCM+. The motion equations were solved by OrcaFlex to obtain the motion response and generator power, as well as the dynamics of the mooring system and aerodynamics of the wind turbine. The waves were assumed to share the same direction as the wind. This study compared the mean values and standard deviations of the motion response, generator power, and mooring line tension between the potential- and viscous-flow approaches by considering the combination of seven wind directions and four current directions under two wave conditions in the Hsinchu offshore area. The numerical prediction shows that the viscous effect has a larger impact on the hydrodynamic properties in the heave, roll, and pitch motions. The angle between the leading mooring line of the system and dominant wind direction in the Taiwan Strait, which comes from the northeast, should be from 120° to 180° in order to deliver a relatively favorable performance of the system. Full article

In March 2020, a ferry (Splendid G.N.V. Company, Italy) moored in the port of Genova (Northwest of Italy) was transformed into a medical care facility for COVID-19. The project intended to help infected patients that required low-intensity care, were discharged from hospitals in the Liguria Region and were not yet able to return home. The aim was to share some of the treatment burden of the completely overcrowded local ashore hospitals and to free up bed spaces for patients in the acute phase of the disease. In this work we highlighted under the health port authority perspective the safety issues that the crew faced resulting from the exceptional and very unusual allocation of ashore medical facilities on a passenger ship. Full article

The holistic perspective model is a concept of three stages that considers the whole of online consumer behavior. It is based on dynamic aspects and overview measurement to demonstrate the preliminary of three stages, including “Pre-purchase”, “Purchase” and “Post-purchase”. There is a shared purpose for all the positive, negative, and hesitation factors that inhibit or encourage online shopping decisions. This model can capture the dynamic and fast-changing elements in online shopping platforms. Most online buying-selling platforms are gaining popularity and growing rapidly. Thus, they should maintain good levels of online customers’ satisfaction. This research presents a balanced investigation model of online consumer purchasing behaviors under uncertainty through the integration of Push-Pull Mooring (PPM) theory and the three stages of online consumer behaviors. In this study, questionnaires were collected from 525 online applications from experienced users of electronic business platforms. The outcome reveals that PPM affects three stages of online consumer behaviors. This means that PPM factors influence online customers during and after online shopping. This research can be used to develop attractive online shopping applications for prospective customers while retaining existing customers, which is the challenge faced by online shopping platforms. Full article

After the first weeks of vaccination against SARS-CoV-2, several cases of acute thrombosis were reported. These news reports began to be shared frequently across social media platforms. The aim of this study was to conduct an analysis of Twitter data related to the overall discussion. The data were retrieved from 14 March to 14 April 2021 using the keyword ‘blood clots’. A dataset with n = 266,677 tweets was retrieved, and a systematic random sample of 5% of tweets (n = 13,334) was entered into NodeXL for further analysis. Social network analysis was used to analyse the data by drawing upon the Clauset–Newman–Moore algorithm. Influential users were identified by drawing upon the betweenness centrality measure. Text analysis was applied to identify the key hashtags and websites used at this time. More than half of the network comprised retweets, and the largest groups within the network were broadcast clusters in which a number of key users were retweeted. The most popular narratives involved highlighting the low risk of obtaining a blood clot from a vaccine and highlighting that a number of commonly consumed medicine have higher blood clot risks. A wide variety of users drove the discussion on Twitter, including writers, physicians, the general public, academics, celebrities, and journalists. Twitter was used to highlight the low potential of developing a blood clot from vaccines, and users on Twitter encouraged vaccinations among the public. Full article

There is a huge energy demand from offshore renewable energy resources. To maximize the use of various renewable energy sources, a combined floating energy system consisting of different types of energy devices is an ideal option to reduce the levelized cost of energy (LCOE) by sharing the infrastructure of the platform and enhancing the power production capacity. This study proposed a combined concept of energy systems by combing a heave-type wave energy converter (WEC) with a semisubmersible floating wind turbine. In order to investigate the power performance and dynamic response of the combined concept, coupled aero-hydro-servo-elastic analysis was carried out using the open-source code F2A, which is based on the coupling of the FAST and AQWA tools by integrating all the possible environmental loadings (e.g., aerodynamic, hydrodynamic). Numerical results obtained by AQWA are used to verify the accuracy of the coupled model in F2A in predicting dynamic responses of the combined system. The main hydrodynamic characteristics of the combined system under typical operational conditions were examined, and the calculated responses (motions, mooring line tension and produced wave power) are discussed. Additionally, the effect of aerodynamic damping on the dynamic response of the combined system was examined and presented. Moreover, a second fully coupled analysis model was developed, and its response predictions were compared with the predictions of the model developed with F2A in order for the differences of the calculated responses resulted by the different modeling techniques to be discussed and explained. Finally, the survivability of the combined concept has been examined for different possible proposed survival modes. Full article

We aim to identify the engagement strategies that higher education students, engaging in emergency online learning in low-resource settings, perceive to be effective. We conducted a sequential mixed-methods study based on Moore’s interaction framework for distance education. We administered a questionnaire to 313 students engaging in emergency online learning in low-resource settings to examine their perceptions of different engagement strategies. Our results showed that student–content engagement strategies, e.g., screen sharing, summaries, and class recordings, are perceived as the most effective, closely followed by student–teacher strategies, e.g., Q and A sessions and reminders. Student–student strategies, e.g., group chat and collaborative work, are perceived as the least effective. The perceived effectiveness of engagement strategies varies based on the students’ gender and technology access. To support instructors, instructional designers, and researchers, we propose a 10-level guide for engaging students during emergency online classes in low-resource settings. Full article

The 2017 U.S. Senate Special Election in Alabama, which was decided on 12 December 2017, was one of the most contentious and scandal-laden political campaigns in recent memory. The Republican candidate, Roy Moore, gained notoriety during the 2017 campaign when a number of women alleged to national media that as teenagers they were subject to sexual advances by Moore, who was then in his early 30s and serving as a local assistant district attorney. The process and results of this particular election provide the heretofore unexamined impact of political scandal on localism or friends-and-neighbors voting in political contests. Based on data from the 2017 special election in Alabama, econometric results presented here suggest that a candidate who is embroiled in political scandal suffers an erosion in the usual friends-and-neighbors effect on his or her local vote share. In this particular case, the scandal hanging over Moore eroded all of the friends-and-neighbors effect that would have been expected (e.g., about five percentage points) in his home county, as well as about 40% of the advantage Moore had at home over his opponent in terms of constituent political ideology. Full article

In the near future, the oceans will be subjected to a massive development of marine infrastructures, including offshore wind, tidal and wave energy farms and constructions for marine aquaculture. The development of these facilities will unavoidably exert environmental pressures on marine ecosystems. It is therefore crucial that the economic costs, the use of marine space and the environmental impacts of these activities remain within acceptable limits. Moreover, the installation of arrays of wave energy devices is still far from being economically feasible due to many combined aspects, such as immature technologies for energy conversion, local energy storage and moorings. Therefore, multi-purpose solutions combining renewable energy from the sea (wind, wave, tide), aquaculture and transportation facilities can be considered as a challenging, yet advantageous, way to boost blue growth. This would be due to the sharing of the costs of installation and using the produced energy locally to feed the different functionalities and optimizing marine spatial planning. This paper focuses on the synergies that may be produced by a multi-purpose offshore installation in a relatively calm sea, i.e., the Northern Adriatic Sea, Italy, and specifically offshore Venice. It analyzes the combination of aquaculture, energy production from wind and waves, and energy storage or transfer. Alternative solutions are evaluated based on specific criteria, including the maturity of the technology, the environmental impact, the induced risks and the costs. Based on expert judgment, the alternatives are ranked and a preliminary layout of the selected multi-purpose installation for the case study is proposed, to further allow the exploitation of the synergies among different functionalities. Full article