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The objective of this research is to develop a method for designing customised pressure garments that can be more accurately applied to a burn wound area. The method includes the use of a 3D digital image of the wounded body part obtained by a body scanner and the development of a 3D pressure garment model and a 2D pattern. The scanned data contain detailed information that cannot be feasibly obtained by manual measurements, such as body curvature. The model parameters include the pressure to be exerted, pressure garment fabric properties and radius of curvature of the cross-sections of scanned body parts. By using a 3D pressure garment model, a 2D garment pattern is developed, and then, a pressure garment is constructed by using the pattern. The technique has been experimentally verified and customised pressure garments are made for a number of volunteer subjects. The customised pressure garments made for the subjects exert pressures close to the design pressure, but vary along the circumference of a given cross-section. The customised pressure garments constructed by using the developed method have shown a more accurate fit to uniformly exert the design pressure onto the whole of the wounded area.

This paper reports on the development of a method for the prediction of clothing pressure of girdles on the human body.

In this paper, we propose to use a standard mannequin dummy to measure the clothing pressure of girdles and from which to predict the pressure on the different human body. An improved mathematical programming method for numerical simulation of cloth wrinkling is investigated.

In general, the prediction equations of the model are effective in estimating the clothing pressure on the human body from the clothing pressure on a standard mannequin dummy.

The method may be used by the manufacturers of girdles to test their products on a dummy to see whether the pressure distribution is satisfactory to the targeted group of consumers. It can also be used by consumers to assess the suitability of girdles based on the estimated clothing pressure, which may be predicted from the pressure pre‐tested on a dummy and the consumer's body characteristics.

Direct measurement of clothing pressure on human body for the evaluation of pressure garments is time consuming, expensive. It is therefore desirable to predict the girdle's pressure instead of the direct measurement on human subjects. The method may be used by manufacturers of girdles as well as by consumers.

The purpose of this study was to categorize the whole body shapes of overweight and obese females in the US and examine apparel fit based on the current ASTM sizing standards related to the body shapes categorized.

Body scan data from 2,672 subjects were used. To categorize their whole body shapes using 97 body measurements, principal component analysis with varimax rotation, a hierarchical cluster analysis and K-means cluster analysis were used. To compare the ASTM sizing standards for plus sizes (curvy and straight) and missy sizes (curvy and straight), five body parts (bust, under bust, waist, top hip, hip) using the formula for fit tolerance (measurement plus half of the interval) were compared with the ASTM sizing standards to determine the size appropriate for each body part.

Five whole body shapes among overweight and obese females in the US were categorized: Rectangle-curvy; parallelogram-moderately curvy; parallelogram-hip tilt; inverted trapezoid-moderately curvy and inverted trapezoid-hip tilt. When the body measurements in each body shape were compared with the current ASTM sizing systems for both misses and plus sizes, four-fifths or more of overweight and obese female adults in the US would find it difficult to obtain a perfect fit for both tops and bottoms.

Identifying whole body shapes among overweight and obese women in the US contributes significantly, as it will help apparel companies that target the markets of larger women develop a new sizing system. This study is the first attempt to analyze fit by comparing the ASTM sizing charts with body measurements in each body shape group. Further, the study contributes to the body-related literature by filling gaps in missing whole BS categories among overweight and obese females.

Internal gearings are commonly used in transmissions due to their advantages like high-power density. To ensure high efficiency, load-carrying capacity and good noise behavior, a profound knowledge of the local gear mesh is essential. The tooth contact of internal gears relates to a convex and concave surface that form a conformal contact. This is in contrast to external gears, where two convex surfaces form a contraformal contact. This paper aims at a better understanding of conformal contacts under elastohydrodynamic lubrication (EHL) to improve the design of internal gearings.

An existing numerical EHL model is used for studying the characteristic properties of a hard conformal EHL line contact. A hard contraformal EHL line contact is studied as reference. Non-Newtonian fluid behavior and thermal effects are considered. By taking into account the local contact conformity and kinematics, the effects and relevance of the curvature of the lubricant gap and micro-slip are analyzed. In a parameter study, scale effects of the contact radii on film thickness, temperature rise and friction are examined.

The curvature of the lubricant gap and effects of micro-slip are small in hard conformal EHL line contacts. For high micro-slip, it can be neglected. Hence, the modeling of conformal contacts using an equivalent geometry of the contact problem is reasonable. The parameter study shows beneficial tribological aspects of the conformal contact compared to the contraformal contact. Higher film thickness and lower fluid coefficient of friction are observed for conformal contacts, which can be attributed to lower pressures for the case of the same external normal force, or to a higher contact temperature rise for the case of equivalent contact pressure.

Despite its widespread existence, the local geometry and kinematics in hard conformal EHL line contacts like in internal gearings have been rarely studied. The findings help for a better understanding of local contact characteristics and its relevance. The quantified scale effects help to improve the efficiency and load-carrying capacity of machine elements with hard conformal EHL contacts, like internal gearings.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-12-2022-0366/

This paper reports a pressure distribution model that will predict the pressure applied by a pressure garment onto a wounded body segment which could facilitate the production of custom made pressure garments. The model is generated by using the 3D data of the wounded body segment of a patient which are obtained by a non-intrusive non-contact measurement system. The circumference of the body segment is calculated from scanned digital data. Then, a circumference reduction factor is calculated to determine the circumference of the pressure garment in order to apply the design pressure by using a specific fabric with an experimentally determined modulus of elasticity in the circumferential direction. Then, the radius of curvature for each data point in a given layer is calculated and the pressure applied is obtained. Finally, a 3D pressure distribution model for the whole wounded part is constructed by stacking the pressure maps of adjacent layers. The model is verified through a comparison with the actual pressure measured by using custom made pressure garments and volunteer subjects. The comparison shows reasonable agreement. The model enables garment manufacturers/therapists to evaluate the effectiveness of a custom designed pressure garment before it is manufactured and eliminates the need for in-situ pressure measurements.

The purpose of this paper is to describe a method permitting the creation of a realistic model of spherical roller bearing with the aim of determining contact stress and fatigue life based on dynamic loading conditions. The paper also aims to recognize the effect of tolerance values on contact stress and fatigue life. Motion and load transmission in spherical roller bearing occurs within the assembly by elliptical curved contacting surfaces. The stress produced by the transmitted load would be very high because of least contacting area between these surfaces.

The paper describes a methodology to determine contact stress using analytically as well as finite element method for spherical roller bearing. The comparison for the both each approach for contact stress at different loading condition is carried out. Prediction of fatigue life based on dynamic loading conditions for bearing is also determined using finite element model. The effect on induced contact stress and fatigue life by varying tolerances on inner race dimensions have been found out.

The paper suggests that the maximum stress produces at the start or end of the contacting arc under static loading condition in spherical roller bearing. The analytical and finite element approach is in good agreement. The fatigue life prediction is useful for selecting loading conditions for various applications of double row spherical roller bearing. Tolerance level at inner ring raceway radius is kept high because of manufacturing constrain of complex curvature geometric shape.

The present approach does not consider dynamic loading conditions for contact stress analysis. Therefore, researchers are encouraged to analyze the effect of wear, lubrication and other tribological aspects on bearing life.

The paper includes determination of contact stress and prediction of fatigue life for spherical roller bearing using analytical as well as finite element approach. The tolerance values at inner race are identified as per manufacturing constraint based on contact stress and fatigue life.

Stretch fabrics are employed to create compression in garments for medical, sports, and fitness applications. Although potential correlations between wearing compression garments and physiological or performance metrics have been studied, such correlations require knowledge of the actual compression caused by garments. The purpose of this paper is to demonstrate, compare, and contrast different methods for measuring compression delivered by an exemplar compression garment.

The exemplar compression garment is a plain jersey knit maternity band. The compression delivered by this garment was determined via three different methods – Tekscan pressure mapping system, Hohenstein Measurement System (HOSY), and a fabric-based analytical model employing uniaxial fabric tensile data.

HOSY and the fabric-based model, assuming a circular cross section for the garment, provided comparable results for compression versus garment height. However, these methods did not capture the varying compression delivered at different transverse locations when the subject was noncircular in cross section. Assuming an elliptical cross section, the fabric-based model predicted results that were comparable to those measured by the Tekscan system: for example, compressions were approximately 130-160 percent greater at the hip, and approximately 60-100 percent lower at the posterior, than HOSY revealed. Further, the Tekscan system allows the effect of movement on compression to be captured.

This paper compares and contrasts three compression measurement methods and demonstrates the importance of angular position and height dependencies. Further, the fabric-based model is presented as a tool to assist design of compression garments.

This paper seeks to present a novel perspective on the interplay of forces that govern the dynamics of the massively complex multi‐body system that is our physical universe. It offers a consistent, coherent and complete rationale for the phenomenon referred to as “gravitation”. This includes notably, for the first time, an explanation for the mechanism by which “matter tells space how to curve and curved space tells matter how to move”, and also possible causal explanations for the various outcomes of Einstein's equivalence principle.

Starting from the well‐supported premise that elementary particles are formed from closed‐loop electromagnetic energy flows, the likely impact of such constructs on the behaviour of large‐scale dynamic systems is analysed from first principles.

Gravitation is shown to be a natural consequence of such a construct. The warping of space in the presence of gravitating mass, consistent with the view presented by general relativity, is shown to relate to a clearly comprehensible physical structure with a well‐defined causation. Possible explanations are offered for: gravitational time dilation; gravitational red shift; gravitational potential energy; and slowing and bending of light in a gravitational field.

This novel perspective opens a wide range of potential avenues of innovative research, both pure and applied.

A variety of new technologies may prove to be open to development, notably in the aerospace field. Antigravity technologies, whilst amenable to investigation and possible development, may prove highly energy‐intensive.

This paper is totally original and of very significant potential value in various respects.

The use of shoulder protectors is strongly recommended when carrying objects on the shoulder to ensure the health and safety of workers. Thus, this study aimed to develop and verify an ergonomic shoulder protector that considers human body shape and carrying posture from an ergonomic perspective. Ultimately, this study will present a shoulder protector with enhanced fit and safety for carrying workers at construction sites.

The shoulder protector was designed and printed using three-dimensional printing technology with variable side neck points and shoulder point heights to reflect the human body's shoulder line shape and to position the carried object stably on the shoulder. The developed shoulder protectors were evaluated in terms of their fit according to the work posture of the carrier, adherence upon motion and durability through structural analysis.

The design of the shoulder protector for carrying workers followed the shoulder line. It is best placed above the side neck point by 1.0 cm and above the shoulder point by 2.0 cm. Its length is slightly shorter than the human shoulder for superior fit and safety.

The final shoulder protector (FSP) for carrying workers reflects the body curvature while enhancing fit and safety by considering activity and protective factors. As functional studies and evaluations on the need for protectors are scarce, this study provides fundamental data in the evaluation of protective gears.

Contact problems are central to solid mechanics as contact is the principal method of applying loads to a deformable body and the point with resulting stress concentration is often the most critical point within the body. This paper presents a finite element model for the elastic contact between two cylinders at several positions. The effects of friction and surface roughness have been considered. The contact between two skew cylinders is also investigated. Results from finite element model show a good agreement with those of analytical solutions available in the literature. It was seen that the geometry of contacting bodies and orientation of applied load effect highly on contact stresses. Although the effect of surface roughness was seen to be more than that of friction, both of them can be assumed negligible in elastic contact problems.