Proposal of the Measurement Conditions for Hanji–Determination Folding Endurance

This study aims to optimize the measurement conditions of handmade Hanji paper to reduce the time required for measurement while meeting folding endurance standards, for various basis weights. Thirteen types were selected, including 12 types of Hanji with grammages of 17 g/m2, 30 g/m2, and 45 g/m2, and one type of 75 g/m2 copy paper, and 24 sheets were prepared in the laid and chain directions. Subsequently, folding endurance experiments at different load (14.72 N, 9.81 N, 4.91 N) and specimen width conditions (15 mm, 10 mm, 5 mm) were performed, using a 4-MIT folding endurance tester. The results showed that, for specimen widths of 15 mm and 10 mm under a load of 4.91 N, the folding endurance falls within the reference range (10∼10000 times). In particular, reduced folding endurance range and measurement time were observed at a width of 10 mm under a load of 4.91 N. Moreover, the endurance trend lines based on the average values of load and specimen width ranges enabled the prediction of the folding endurance within those ranges, according to the decreasing slope. Furthermore, for a specimen width of 15 mm under a load of 4.91 N, the folding endurance in the comparison group (35 to 17723 times) significantly exceeds the upper limit of the reference range (10∼10000 times). Therefore, the measurement conditions of 4.91 N with a specimen width of 10 mm are proposed.

Effectiveness of an Assistive Instrument for Physical Therapists with Visual Impairment to Conduct the Muscle Tightness Test

Disability sports have been globally promoted to achieve an inclusive society. However, the current opportunities for people with disabilities are few in terms of participating in supporting positions, such as athletic trainers. In Japan, many people with visual impairment (VI) work as physical therapists; thus, they can become active as medical staff in the sports field. An example of a medical assessment is the muscle tightness test (MTT); however, conducting it is expected to be difficult for people with VI. To improve this difficulty, the current study developed an assistive instrument (AsI) and examined its effectiveness. We recruited 22 physical therapists with VI. The measurement for MTT targeted the hamstrings, iliopsoas, gastrocnemius, and quadriceps. The participants performed the MTT using a universal goniometer (UG) and the AsI and filled up a questionnaire. AsI was compared against UG based on three aspects, namely, ease, accuracy, and measurement time. In terms of ease, significant differences were observed in 9 out of 12 questionnaire items. The mean (SD) score for “Comprehensive ease of the MTT” improved from 2.8 (1.0) to 3.9 (0.8). For accuracy, the AsI yielded a decrease in the total error of the measurement. Lastly, the measurement time for AsI was longer than that for the UG. Therefore, the AsI was effective in terms of ease and accuracy, whereas measurement time remained as an issue.

The Direct Subjective Refraction: Unsupervised measurements of the subjective refraction using defocus waves

We present the Direct Subjective Refraction (DSR), a new subjective refraction method, and validate it vs the Traditional Subjective Refraction (TSR) and an unsupervised version of it (UTSR). We project an optotunable lens onto the eye to create Temporal Defocus Waves produces flicker and chromatic distortions, minimum when the mean optical power of the wave matches the spherical equivalent of the eye. 25 subjects performed the DSR visual and UTSR tasks without supervision. DSR is more repeatable than TSR and UTSR (standard deviations ±0.17D, ±0.28, and ±0.47D). The time per repetition of DSR is only 39s (almost 6 min for TSR). Cyclopegia severely affects UTSR, but not DSR, confirming that the DSR task de-activates the accommodative system. DSR is a new method to obtain the spherical equivalent that does not requires supervision and overpasses existing subjective methods in terms of accuracy, precision, and measurement time.

The effect of the addition of granite powder to the primer on the pull-off strength of epoxy resin coatings

This article describes the effect of adding waste granite powder to the epoxy resin layer on its pull-off strength. The substrate was C30 / 37 concrete. The priming resin was modified with 10%, 20%, 30%, 40%, 50%, and 60% of granite powder. For control purposes, a sample was also made without the addition of powder. For each material configuration, four strength tests were carried out with the use of an automatic device recording both the pull-off strength and the measurement time. The obtained results were compared with the control sample. The best result in the test was obtained with the addition of 20%, which gave an increase of 19% compared to the reference sample. An equally good result was obtained with the addition of 10% granite powder (increase by 11%). The addition of a larger amount of the additive resulted in a decrease or a slight increase in the pull-off strength compared to the reference sample. Additionally, the additive has been found to darken the coating, and the coating becomes completely opaque when added above 50%.

Property requirements of vibration measurements in wind turbine drivetrain bearing condition monitoring

Wind turbine drivetrain bearing failures continue to lead to high costs resulting from turbine downtime and maintenance. As the standardised tool to best avoid downtime is online vibration condition monitoring, a lot of research into improving the signal analysis tools of the vibration measurements is currently being performed. However, failures in the main bearing and planetary gears are still going undetected in large numbers. The available field data is limited when it comes to the properties of the stored measurements. Generally, the measurement time and the covered frequency range of the stored measurements are limited compared to the data used in real-time monitoring. Therefore, it is not possible to either reproduce the monitoring or to evaluate new tools developed through research for signal analysis and diagnosis using the readily available field data. This study utilises 12 bearing failures from wind turbine condition monitoring systems to evaluate and make recommendations concerning the optimal properties in terms of measurement time and frequency range the stored measurements should have. The results show that the regularly stored vibration measurements that are available today are, throughout most of the drivetrain, not optimal for research-driven postfailure investigations. Therefore, the storage of longer measurements covering a wider frequency range needs to begin, while researchers need to demand this kind of data.