A practical two parameter model of pile-soil gapping for prediction of monopile offshore wind turbine dynamics

Monopile mounted offshore wind turbines (OWTs) are expected to experience a very large number of cyclic loads throughout their operational lifetime, and the existing p-y method of foundation modelling does not fully account for the effects of dynamic cyclic loading, such as pile-soil gapping. In this paper a dynamic model based on the beam on non-linear Winkler foundation scheme with a novel algorithm capable of capturing the effects of pile-soil gapping is presented. It can account for gap cave-in, and the resulting gap size can react dynamically to changing loading amplitudes, using only two calibration parameters. Static and dynamic cyclic loaded model validations are presented, and give very good agreement with experimental results, performing better than existing p-y curves for dynamic loading. The model is also applied to an OWT case study and predictions of natural frequency reduction due to soil erosion agree well with measured results. It is shown that the inclusion of gapping may result in a significant decrease to the natural frequency prediction of OWTs relative to the value predicted without gapping. As such, not to consider gapping could lead to unconservative predictions, and any additional soil degradation throughout the serviceable lifetime could therefore result in unwanted resonance. The method provided in this paper provides a simple and accurate model to predict this behaviour which is crucial to ascertain during the design phase.</p

Modelling the impact of gapping behaviour on monopile mounted offshore wind turbine dynamics

Increased demand for renewable energy production has stimulated interest in the offshore wind turbine (OWT) industry as a viable solution, and with OWTs growing larger in scale, further research is required into the dynamics of these newer structures. The majority of installed OWTs to date are built upon monopile foundations, and it is widely acknowledged that the current design methods for offshore piles are not appropriate for the large diameter piles required. This paper uses a novel pile-soil gapping algorithm to simulate the effects ofdegradation to the soil conditions in the sea bed. Using a 1D Winkler beam spring approach, a dynamic model is validated for prediction of the natural frequencies of several OWT case studies, and the gapping algorithm is shown to reproduce well the reduction in natural frequency likely attributed to soil degradation measured from an OWT in Kentish Flats wind farm. It is found through the simulation of rotor-stop tests that the presence of gapping decreases the measured natural frequency, and this effect is greater for the monopile foundations with a smaller slenderness ratio

The Mental Health Impacts of COVID-19 on PK-12 Students: A Systematic Review of Emerging Literature

The mental health impact of the coronavirus disease 2019 (COVID-19) pandemic on PK-12 youth is likely an urgent and enduring concern, yet research on this topic is still emerging. To synthesize current knowledge, the researchers conducted a systematic review of empirical studies exploring the mental health impacts of COVID-19. Five themes emerged across 104 included studies: (a) the pandemic proved widely disruptive to PK-12 youth; (b) there was a clear connection between the mental health of caregivers (e.g., parents) and children; (c) the pandemic broadly increased levels of stress, anxiety, and depression in PK-12 youth; (d) students were particularly affected on the basis of age, gender, race/ethnicity, socioeconomic status, and previous mental health or disability diagnosis; and (e) youth demonstrated negative and positive coping strategies and even saw some positive mental health outcomes during the pandemic. Implications for research, practice, and policy are discussed.; The mental health impact of the coronavirus disease 2019 (COVID-19) pandemic on PK-12 youth is likely an urgent and enduring concern, yet research on this topic is still emerging. To synthesize current knowledge, the researchers conducted a systematic review of empirical studies exploring the mental health impacts of COVID-19. Five themes emerged across 104 included studies: (a) the pandemic proved widely disruptive to PK-12 youth; (b) there was a clear connection between the mental health of caregivers (e.g., parents) and children; (c) the pandemic broadly increased levels of stress, anxiety, and depression in PK-12 youth; (d) students were particularly affected on the basis of age, gender, race/ethnicity, socioeconomic status, and previous mental health or disability diagnosis; and (e) youth demonstrated negative and positive coping strategies and even saw some positive mental health outcomes during the pandemic. Implications for research, practice, and policy are discussed

On the assessment of passive devices for structural control via real-time dynamic substructuring

In this work, the applicability of a dynamic testing technique known as real-time dynamic substructuring (RTDS) for the assessment of passive vibration suppression systems in seismic protection of buildings is analysed. RTDS is an efficient method for the assessment of dynamic and rate-dependent behaviour of systems subjected to dynamic excitation at real scale and in real scenarios. The actuators used in RTDS test introduce additional undesirable dynamics into the system, which are often not fully compensated for in the actuator controller—these dynamics are commonly approximated as a feedback delay. To guarantee the validity and accuracy of an RTDS simulation, a stability analysis of the substructured system that includes the feedback delay should be carried out. In this paper, we present explicit analyses that provide a dynamic characterization of the delay-induced phenomena in RTDS simulations when considering passive vibration suppression systems with strong nonlinearities. We present a complete set of closed-form expressions to describe the main phenomena because of delay in terms of dynamic stability in an RTDS simulation. Through an experimental study, we confirm the existence of self-sustained oscillations caused by very small delay in the feedback loop. This lead the system to instability in the form of high-frequency oscillations. Copyright © 2011 John Wiley & Sons, Ltd

An experimental test of green management information system effects on carrier selection: weigh station and tollbooth bypass technology adoption

In a highly competitive price-driven industry, carriers are continuously searching for opportunities to differentiate their offerings, minimize operational costs, and appeal to shippers. At the same time, environmental sustainability has evolved from being trendy jargon into a requirement for competitive supply chain management. It is at the intersection of these two modern topics that the current study identifies a new carrier selection attribute based on a specialized type of green management information system. We apply social exchange theory to hypothesize carrier price and green technology adoption effects on shipper purchase intent. The hypothesized direct and interaction effects are tested by way of a vignette-based experiment, with a sample of full-time working professionals. The supported hypotheses collectively suggest that the adoption of weigh station and tollbooth bypass technology, as a type of environmentally sustainable information system, positively affects transportation carrier selection and attenuates the negative effect of a carrier’s price on shippers’ purchase intentions. These research findings offer unique theoretical, practical, and policy implications surrounding the trucking carrier selection decision

Human emotional response to energy visualisations

This is the post-print version of the final paper published in International Journal of Industrial Ergonomics. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2012 Elsevier B.V.Past research has found that frequent energy usage feedback is an important factor in reducing home energy consumption, and that the sensory appeal and cognitive relevance of the feedback are key components of user engagement with energy systems. The visual design of the information interface is important not just due to its role in communicating data of cognitive relevance, but also because the choice of information type and format is important towards achieving interactive Hebbian learning. The objective of the current research study was to investigate the possible effect of image format on the human emotional response to scenes of energy systems, and to evaluate whether any gender related differences in emotional response occurred. An automated PC-based test was developed which utilised five visual image formats (Optical Gray-Scale, Optical Coloured, Optical Augmented, Infrared Gray-Scale and Infrared Blue-Red) and nine home energy scenes (hot water boiler, radiator, water faucet, kitchen oven, tea kettle, toaster, electrical connector, laptop computer and tea mug). The emotional response of the participant was measured in the automated test by means of a Self-Assessment Manikin (SAM) which provided symbolic graphical representations of the human body under various degrees of emotional response, and associated Likert format rating scales for the valence and activation level of the emotional response. Comparison of the results obtained for the different visual scenes suggests that the greatest level of human emotional activation was achieved by the Infrared Blue-Red (thermal image) format, and that, generally, coloured images provided higher levels of emotional activation than gray-scale images. The increased activation achieved by the infrared images suggests attention capturing potential due to novelty, or due to the direct link to heat and energy, or both. Significant differences in emotional response (both activation and valence) were found to occur as a function of gender. The current results provide first guidance which a designer can use when choosing image spectrum and colours to represent energy systems on the displays of thermostats, smart meters and the energy devices. Relevance to industry - The current results provide first guidance which a designer can use when choosing image spectrum and colours to represent energy systems on the displays of thermostats, smart meters and the energy devices. Such design guidance is currently lacking internationally but is of increasing importance due to the expansion of digital devices, internet services and the upcoming internet-of-things

Bilateral Syphilitic Optic Neuropathy with Secondary Autoimmune Optic Neuropathy and Poor Visual Outcome

We describe the case of a 65-year-old man who suffered progressive visual loss despite appropriate treatment of ocular syphilis. Our patient initially presented with a unilateral 6th nerve palsy and associated double vision, which self-resolved over 6 months. His ophthalmic examination was otherwise normal. 12 months after the initial complaint, he represented with dyschromatopsia, reduced visual acuity, tonic pupils, and optic nerve atrophy. He tested positive for syphilis and was admitted for treatment of neurosyphilis with high-dose benzylpenicillin. Despite treatment, at a 4-month review his visual acuity remained poor and progression of optic nerve atrophy was noted alongside the development of bilateral central scotomas. Further testing was congruent with a diagnosis of autoimmune optic retinopathy. We propose this to be secondary to his syphilitic infection. Syphilis is known as the “great mimicker,” and despite being quite treatable, this case highlights ongoing complexity in the diagnosis and management of syphilis, unfortunately with a poor visual outcome

Self-assembled peptide habitats to model tumor metastasis

Metastatic tumours are complex ecosystems; a community of multiple cell types, including cancerous cells, fibroblasts, and immune cells that exist within a supportive and specific microenvironment. The interplay of these cells, together with tissue specific chemical, structural and temporal signals within a three-dimensional (3D) habitat, direct tumour cell behavior, a subtlety that can be easily lost in 2D tissue culture. Here, we investigate a significantly improved tool, consisting of a novel matrix of functionally programmed peptide sequences, self-assembled into a scaffold to enable the growth and the migration of multicellular lung tumour spheroids, as proof-of-concept. This 3D functional model aims to mimic the biological, chemical, and contextual cues of an in vivo tumor more closely than a typically used, unstructured hydrogel, allowing spatial and temporal activity modelling. This approach shows promise as a cancer model, enhancing current understandings of how tumours progress and spread over time within their microenvironment. © 2022 by the authors. Licensee MDPI, Basel, Switzerland

Intervening to eliminate the centre-effect variation in home dialysis use: protocol for Inter-CEPt - a sequential mixed-methods study designing an intervention bundle

Introduction: Use of home dialysis by centres in the UK varies considerably and is decreasing despite attempts to encourage greater use. Knowing what drives this unwarranted variation requires in-depth understanding of centre cultural and organisational factors and how these relate to quantifiable centre performance, accounting for competing treatment options. This knowledge will be used to identify components of a practical and feasible intervention bundle ensuring this is realistic and cost-effective. Methods and analysis: Underpinned by the non-adoption, abandonment, scale-up, spread and sustainability framework, our research will use an exploratory sequential mixed-methods approach. Insights from multisited focused team ethnographic and qualitative research at four case study sites will inform development of a national survey of 52 centres. Survey results, linked to patient-level data from the UK Renal Registry, will populate a causal graph describing patient and centre-level factors, leading to uptake of home dialysis and multistate models incorporating patient-level treatment modality history and mortality. This will inform a contemporary economic evaluation of modality cost-effectiveness that will quantify how modification of factors facilitating home dialysis, identified from the ethnography and survey, might yield the greatest improvements in costs, quality of life and numbers on home therapies. Selected from these factors, using the capability, opportunity and motivation for behaviour change framework (COM-B) for intervention design, the optimal intervention bundle will be developed through workshops with patients and healthcare professionals to ensure acceptability and feasibility. Patient and public engagement and involvement is embedded throughout the project. Ethics and dissemination: Ethics approval has been granted by the Health Research Authority reference 20-WA-0249. The intervention bundle will comprise components for all stake holder groups: commissioners, provider units, recipients of dialysis, their caregivers and families. To reache all these groups, a variety of knowledge exchange methods will be used: short guides, infographics, case studies, National Institute for Health and Care Excellence guidelines, patient conferences, ‘Getting it Right First Time’ initiative, Clinical Reference Group (dialysis)

Exile Vol. XVI No. 2

PREFACE 3 ESSAY Observations At The Gap by Paul A. Dimitruk 4 Those Who Choose Words By Keith McWalter 5-6 On Victoria\u27s England by Paul A. Dimitruk 7-8 Facts Are The Enemy of Truth by Nancy Gutierrez FICTION Harmon by Barbara Mackey 22-25 Pilgrimage by Keith McWalter 35-44 ARTWORK by Wandi Solez: 6, 15, 23, 27 by Ken Wernz 10 by Stephen Swift 11 by Laura M. Hyslop 12 by Skip Staudt 19 by W. A. Hoffman 25 by Mary Ann Kowaski 34 by Jo Ann Orgo 40 PHOTOGRAPHY by Roger Block 16 by Tim Heath- all other POETRY My Poems by Susan Hallock 13 Counter-Fugue At Six-Thirty by Sherry Stodola 14-16 Apple Tree Poem by Darby Williams 17 When Snow Falls Into A Pond by Bruce Kidd 17 Woman-Man by Darby Williams 18 Transcendence by Wandi Solez 20 Paris Reflection by Wandi Solez 20 A Sleepless Night In Valencia, Spain by Wandi Solez 21 # 319 by Wandi Solez 21 Strange Lady by John Gillespie 26 Strange Lady II by John Gillespie 26 Where The Hell Is Rembrandt? by John Loveland 26 Years Ago by John Whitt 29 I\u27ve Finished Growing Now by Keith McWalter 29 Charisma by John Whitt 30 I Thought Of Cutting by John Loveland 31 Make Me Eat Peanut Butter by Fred Walton 31 The Cat by John Loveland 32 On The Rim by John Whitt 33 Undercurrent by Keith McWalter 33 Cover: Gail Lutsch Layouts: Keith McWalte