Factors influencing the perceived usability of wearable chair exoskeleton with market segmentation: A structural equation modeling and K-Means Clustering approach

The sudden implementation of work-from-home setup has caused the rise of sedentary position among employees which led to an increase in development or worsening of musculoskeletal disorders. To help mitigate this problem, wearable assistive devices such as wearable chairs have been argued to be beneficial. Several studies have expounded on the benefit of using this, however little to no available device is yet present in the Philippines. To which, businesses and developers could capitalize on this aspect. This study examined the perceived usability of wearable chair exoskeleton in the Philippines by integrating the Unified Theory of Acceptance and Use of Technology (UTAUT2) and System Usability Scale (SUS). A questionnaire was developed and distributed to 365 residents in the Philippines to measure the factors and their relationship to perceived usability accurately. Indicators and measures used in the questionnaire were derived from existing literature on technology acceptance and usability evaluation. Partial least squares structural equation modeling (PLS-SEM) was used for this study. Results revealed that perceived usability was significantly influenced by usage behavior. At the same time, habit, hedonic motivation, and performance expectancy significantly influenced the behavioral intention of the wearable chair exoskeleton. K-Means clustering was also utilized to identify clusters of target users of the wearable chair in the country, such as high-value customers, core customers, and low-value customers. Results indicated that demographic factors such as females, 30 years old and below, earning Php45,000 and above monthly, and living in a city are highly likely to utilize the product. The findings of this study can be applied and extended as a theoretical framework for future researchers of consumer behavior and exoskeleton developers for enhancing the innovation and usability of this new technology. This study may also be used and capitalized by investors to strategize the development and marketing of the exoskeletons among industrial and teleworkers worldwide.     

Influence mechanism of icon semantics on visual search performance: Evidence from an eye-tracking study

Explicit icon semantics can reduce the difficulty of understanding complex visual information. Optimizing the icon semantics and text semantics of icons can effectively improve the cognitive performance of digital interfaces. This paper adopts visual search tasks to study the effects of different combinations of icon semantic familiarity and the presence or absence of text on icon search performance under horizontal and vertical layouts. The behavioral experiment results show that under two layouts: 1. The main effect of icon semantics is significant, and the search performance increases with the increase of semantic familiarity. 2. The main effect of text is significant, and the search performance is negatively correlated with the addition of text. The eye movement experiment found that the semantic familiarity of icons had a significant impact on average fixation time. Furthermore, the number of fixation points changed significantly after the text variable was added. Therefore, there was no significant difference in the number of fixation points in the horizontal layout, and icon semantics was the main influencing factor in visual search. In the vertical layout, there was no significant difference in average fixation time, and text was the main influencing factor of visual search. The results show that the semantic familiarity of icons and different combinations with or without text significantly affect visual search performance in horizontal and vertical layouts. This paper provides a theoretical reference for the combination of icons and text in interface design.     

Association between pain intensity in the neck and components of a workstation: A cross-sectional study on Japanese office workers

This study aimed to investigate the association between inappropriate workstation components and neck pain intensity. This cross-sectional study was conducted on 309 Japanese office workers. Workstation questionnaires were developed based on previous studies and consisted of 11 items that assessed the armrest, monitor screen, desk, and keyboard. For each of the 11 items, we defined whether the item was “inadequate” based on previous studies. Neck pain experienced was measured using a numerical rating scale (NRS) of 0–10, and the NRS scores were categorized into three (0: “no pain,” 1–3: “low pain intensity,” and 4–10: “high pain intensity”). Crude and adjusted ordered logistic regressions were used to determine the association between the inadequate workstation and neck pain intensity. In the first analysis model, each item of the workstation questionnaire was used as an explanatory variable. Then, in the second analysis model, the number of inadequate workstation components was used as the explanatory variable. Ordered logistic regression analyses showed that the distance of the eye to the monitor was significantly associated with neck pain intensity (crude, OR: 2.21; 95% CI: 1.41–3.19; adjusted, OR: 1.79; 95%CI: 1.08–2.50). The number of inadequate workstation components had a significant positive association with neck pain intensity (crude, OR: 1.19, 95%CI: 1.04–1.34; adjusted, OR: 1.15, 95% CI: 1.00–1.32). The results of this study suggest that the distance between the eye and the monitor might be the most important workstation factor contributing to neck pain, and workstation components should be assessed collectively.     

Development of new shoe sizing system for women based on regression analysis of foot shapes

This study aims to demonstrate a new method of developing a shoe sizing system with a standard fitting for each size for Bangladeshi women based on foot measurements. In this study, bivariate correlation analysis was carried out to determine key foot dimensions of 976 women aged 20 to 60. Simple linear regression analyses of key parameters against foot length (FL) were conducted, and the regression equations assisted in determining grading value and size-fit combinations. Nine sizes with three fittings (narrow, standard, and wide) each were generated where the grading values were 6 mm, 5 mm, 2 mm, and 4 mm for FL, joint girth (JG), joint width (JW), and arch length (AL), respectively. Cross-tabulation analysis verified the sizing system with a coverage rate 94.98% of JG, 88.02% of JW, and 98.77% of AL, where standard fittings covered the maximum number of participants. This study could benefit women in choosing accurate shoe sizes for their feet to ensure proper shoe fitting.Relevance to industryThe proposed new shoe sizing system could assist the footwear industries in manufacturing women's shoes in different sizes with appropriate sizing and grading values, which will provide better fitting than existing systems. In addition, industries could produce shoes with a smaller number of size-fit combinations to accommodate most women's feet.     

The embedded single-fibre dynamic load test — a new non-destructive interphase investigation tool

Embedded single-fibre tests are commonly used to investigate fibre/matrix adhesion. However, unstable crack propagation renders these destructive tests hard to interpret. Most of the relevant theories apply an energy or a strength criterion to indirectly deduce interphase properties from the obtained results. A new method, the embedded single-fibre dynamic load (SFD) test, was developed to measure interphasial viscoelastic properties directly in a non-destructive way. Using different fibres in combination with poly(phenylene sulfide) in a comparative study, it is shown that results from the SFD test correlate well with those from single-fibre pull-out (SFP) tests. The morphology is established as a key link for an understanding of the fracture behaviour as well as the dynamic-mechanical behaviour of the interphase in fibre-reinforced composites.     

A link between dispersion models and monitoring data: The estimate of source term

An important application of real-time atmospheric dispersion models is the link between model results and field measurements to achieve an estimate of the source term of a continous realease. In this paper a method for the evaluation of the emission rate (STEP: Source Term Estimate Program) is presented. STEP doesn't depend on the dispersion model used and is based on few, simple considerations about the cause of the commonly observed scatter between measured and computed concentration values at fixed sample points. The results of two STEP tests are presented: firstly, it has been validated against a set of tracer data collected during two meteorological and diffusion campaigns; secondly, a sensitivity study with respect to meteorological parameters and to the number of monitoring data available was carried out.     

Effect of tissue type and variety on cell wall chemistry of onion (Allium cepa L.)

The purpose of this study was a comparative examination of the cell wall chemistry of component tissues of different varieties of onions (Allium cepa L. cv Sturon, Durco, Hysam, Grano de Oro and Caribo). Cold alcohol-insoluble residues (CAIRs) were prepared and were extracted sequentially with water, imidazole, CDTA, Na₂CO₃ and 0.5 M KOH to leave a residue. These were analysed for their carbohydrate compositions. On a whole organ basis, the cell wall carbohydrate composition was similar for each variety studied, and no significant change resulted from commercial storage, with or without sprout suppressant. However, there were significant differences in the carbohydrate composition of cell walls from different tissues. Cell walls of inner leaf bases contained galactoserich pectic polysaccharides. Outer layers had progressively less pectic galactose, and the outer brown skin contained virtually none. This was accompanied by changes in water- and CDTA-soluble polysaccharides and may be related to the dry and protective nature of the non-lignified outer skin. The differences in cell walls from different tissues provide the basis for developing processing methods for exploiting onion waste.     

COMIS—an international multizone air-flow and contaminant transport model

A number of interzonal models have been developed to calculate air flows and pollutant transport mechanisms in both single and multizone buildings. A recent development in multizone air-flow modeling, the COMIS model, has a number of capabilities that go beyond previous models, much as COMIS can be used as either a stand-alone air-flow model with input and output features or as an infiltration module for thermal building simulation programs. COMIS was designed during a 12 month workshop at Lawrence Berkeley National Laboratory (LBNL) in 1988–1989. In 1990, the Executive Committee of the International Energy Agency's Energy Conservation in Buildings and Community Systems program created a working group on multizone air-flow modeling, which continued work on COMIS. The group's objectives were to study physical phenomena causing air flow and pollutant (e.g., moisture) transport in multizone buildings, develop numerical modules to be integrated in the previously designed multizone air flow modeling system, and evaluate the computer code. The working group supported by nine nations, officially finished in late 1997 with the release of IISiBat/COMIS 3.0, which contains the documented simulation program COMIS, the user interface IISiBat, and reports describing the evaluation exercise. This paper serves as an introduction for the other publications included in this Special Issue.