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This study demonstrates the application of a new experimental technique for laboratory-scale simulation of the open-die forging process, known as cogging, an intermediate hot-working process necessary to design an optimised microstructure in the advanced engineering titanium alloy Ti-6Al-4V. Small test-bars of Ti-6Al-4V alloy were subjected to multi-directional cogging operations at elevated temperatures (950–1050 °C). The as-received material, prior to forging, underwent heat treatments to coarsen the initial grain structure, to better simulate the industrial-scale intermediate microstructure (i.e.,β recrystallised) and to help prove the capability of the set-up to achieve microstructure modification via globularisation (below β-transus), and recrystallisation (dynamic and static) and recovery mechanisms (above β-transus) within the cogged material. The influences of hot working parameters on deformation localisation, width of α platelets, and globularisation within the resulting microstructure variation have been investigated using light microscopy (LM), Vickers hardness (HV) testing, and electron backscatter diffraction (EBSD). The cogged Ti-6Al-4V alloy specimens underwent various microstructural evolution stages after hot forging, thus indicating successful application of the designed miniaturised open-die forging apparatus for high temperature experimentation and characterisation studies. This will be suitable for low-cost small-scale trials to determine the key process parameters affecting the onset of microstructure evolution during open-die forging (e.g.,ingot-to-billet conversion) of the Ti-6Al-4V alloy, prior to large-scale trials which are rather more expensive.

Background:The COVID-19 pandemic and its social restrictions accelerated the expansion of virtual clinical care, and this has been reported to be safe, low cost and flexible.Aim:This study aimed to examine nursing practices and patient satisfaction with unscheduled nurse-led virtual care for people with diabetes.Methods:A cross-sectional descriptive survey of clinical nurse specialists and patients was carried out, using an activities log for nursing practices and a satisfaction and enablement survey for callers.Findings:Patients reported high satisfaction levels and greater self-confidence in keeping themselves healthy after receiving virtual care. Most calls (74.8%) from patients were for advice and education. Each call led to an average of 2.5 actions for the clinical nurse specialist.Conclusion:The service is highly valued and is effective, but adds to the nurse workload burden.

ABSTRACTThe relationship between railway track-bed stresses and speed is essential when performing track foundation design. Current approaches to describe this relationship are typically empirical and multiply the static track response by a dynamic amplification factor to account for speed effects. This paper develops an alternative method for dynamic amplification factor generation instead of numerical simulation. A vehicle–track dynamics model is presented, capable of simulating the subgrade dynamics considering random track irregularities. First, samples of irregularity are generated based on a mean vertical track profile power spectral density. A range of train speeds and track-spectrum cumulative probabilities are computed using the numerical model before analyzing the resultant surface stresses. The resulting dynamic amplification factors follow a Gumbel distribution. Data normalization is performed before developing a bespoke dynamic amplification function. Based on speed, track-spectrum cumulative probability, and p-values, the proposed model yields dynamic amplification predictions within 5% of the simulated values.