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This study aimed to evaluate the performance attributes relevant to thermal wear comfort of the commercially available hip protective pads and materials intended for impact protection that can be used for the hip protective pad.

The performance attributes relevant to thermal wear comfort (i.e. dry thermal resistance and evaporative resistance) of the pads were tested using MTNW Integrated Sweating Guarded Hotplate (iSGHP).

It was found that: the pad with more porous structure has more advantages in terms of evaporative resistance; the permeability index will be higher on the pad with an opening such as a segmented pad; the permeability index will be lower on the thicker and larger pad. The pocket fabric with open structure will have lower dry thermal resistance and evaporative resistance.

The study results showed that the properties of the utilised materials influenced thermal comfort performance. These results could be useful for designing and engineering hip protective garments.

This paper aims to examine the influence of hip protective clothing on ensemble performance attributes related to thermal comfort. It also explores the effect on protective pads of various materials and the arrangements of material. The thermal comfort characteristics are thermal insulation and moisture vapour resistance.

For this research, four ensembles of clothing were used: one ensemble without hip protective clothing and three ensembles with hip protective clothing. A thermal manikin was used to test the thermal insulation and moisture vapour resistance of the ensembles.

The findings revealed that incorporating hip protective clothing into the clothing ensembles influenced the thermal resistance and moisture vapour resistance of the ensemble. In the “all zones group,” the influence of the hip protective clothing depended on clothing style, with hipster-style clothing producing insignificant changes. In the “hip zones group” and “stomach and hip zones group,” hip protective clothing strongly influenced the thermal comfort attributes of ensembles. Pad material and volume play important roles in these changes in thermal comfort attributes.

These outcomes are useful for the design and engineering of hip protective clothing, where maximizing protection while minimizing thermal and moisture vapour resistance is critical for wear comfort and adherence in warm or hot conditions. The designer should consider that material, volume and thickness of protective pad affect the overall thermal comfort attributes of the hip protective clothing.

The purpose of this paper is to investigate the influence and relationship of segment area and opening area in segmented protective pad in comparison to non-segmented pad to the energy absorption and performance attributes relevant to thermophysiological wear comfort.

The compressive stress-strain curves were obtained using Instron Tester and were used to analyse the energy absorption of the pads and the segmented pad assemblies. The dry thermal resistance and evaporative resistance of the non-segmented and segmented protective pads were obtained using MTNW Sweating Guarded Hot Plate.

The compression test results and performance attributes relevant to thermophysiological wear comfort test result demonstrated that the area segment and opening area of segmented pad influenced their energy absorption value, dry thermal resistance value and evaporative resistance value (permeability index value).

The results are expected to be useful for design and engineering of hip impact protective garments. Hip impact protective pads are used to prevent hip fractures in elderly people as a result of fall.

This study aimed to determine the peak impact force and force attenuation capacity of weft-knitted spacer fabrics intended for padding that can be used for human body protection against impact.

A total of five weft-knitted spacer fabrics were fabricated with four different diameters of nylon monofilament yarns and one doubled monofilament yarns, respectively. The impact performances of the weft-knitted spacer fabrics were tested using a drop test method with a customized test rig to simulate falling. Impact tests were conducted on single- and multilayered experimental spacer fabrics to investigate the peak impact force and force attenuation capacity.

It was found that weft-knitted spacer fabric with a coarser or larger diameter of monofilament spacer yarn generated lower impact force and higher force attenuation capacity, thus resulting in better impact performance. Greater force attenuation can be achieved by utilizing a higher number of spacer fabric layers. However, the increase in thickness must be considered with the spacer fabric end use.

This study employed relatively coarse nylon monofilament yarn as spacer yarns to gain knowledge on the impact performance of weft-knitted spacer fabrics compared to warp-knitted spacer fabrics which are more common. The results showed that the diameter of spacer yarn significantly influenced the impact performance of the experimental weft-knitted spacer fabrics. These results could be useful for designing and engineering textile-based impact protectors.

Fracture experiments on real human bodies to examine the protected positions and protective devices for the development of protective clothing to manage fractures is exceedingly difficult. Thus, the experimental design will have limitations, more of which are imposed if subjects are elderly people. To circumvent these limitations, this study proposes a finite element model of the hip joint in elderly women with virtual impact simulations that can replace actual fall and impact tests, and examine the positions and characteristics of fractures resulting from taking a fall.

The hip joints were modeled after the average horizontal surface size and cross-sectional shapes of the lower extremities (waist to knee) in 439 elderly Korean women in that age group. The model was composed of bones, cartilages, and soft tissue.

The fracture was examined by comparing the maximum stress on the hip joint by applying a point force to its adjacent surface. The vulnerable part in the hip joint neck with a high risk of fracture risk on an impact could be determined and used to set the protective device attachment position.

It is significant that this study has developed a partial model of the human body that can be used for a relatively simple simulation by minimizing the highly complex human body as much as possible. Furthermore, the model is easily applicable to the designing of protected positions and protective devices for the development of special clothing, for hip joint fracture prevention.

The purpose of this paper is to develop a system to design a bulletproof pad for chest protection using three-dimensional body scan data.

Body data were divided into arbitrary number of groups based on the standard normal distribution theory, considering the width and height of the upper body. Several parameters were used to define the cover area of the bulletproof pad, and the shape of this area of each model in a group was averaged to generate the standard bulletproof pad model for that group.

It is possible to use three-dimensional body scan data in the design process of a mass-customized bulletproof pad for chest protection.

It is expected that it would be possible to design not only bulletproof pad but also many kinds of body-related products that need to reflect the shape of body using the methodology developed in this study.

Using this system, the mass customization of special garments and equipment would be possible, which will improve the wearers’ comfort and work efficiency.

Three-dimensional body measurement, parametric definition of cover area and user interface for shape modification developed in this study will facilitate the consumer-oriented product design.

Concrete workers perform physically demanding work in awkward postures, exposing their backs to musculoskeletal disorders. Back-support exoskeletons are promising ergonomic interventions designed to reduce the risks of back disorders. However, the suitability of exoskeletons for enhancing performance of concrete workers has not been largely explored. This study aims to assess a passive back-support exoskeleton for concrete work in terms of the impact on the body, usability and benefits of the exoskeleton, and potential design modifications.

Concrete workers performed work with a passive back-support exoskeleton. Subjective and qualitative measures were employed to capture their perception of the exoskeleton, at the middle and end of the work, in terms of discomfort to their body parts, ease of use, comfort, performance and safety of the exoskeleton, and their experience using the exoskeleton. These were analyzed using descriptive statistics and thematic analysis.

The exoskeleton reduced stress on the lower back but caused discomfort to other body parts. Significant correlations were observed between perceived discomfort and usability measures. Design modifications are needed to improve the compatibility of the exoskeleton with the existing safety gears, reduce discomfort at chest and thigh, and improve ease of use of the exoskeleton.

The study was conducted with eight concrete workers who used the exoskeleton for four hours.

This study contributes to existing knowledge on human-wearable robot interaction and provides suggestions for adapting exoskeleton designs for construction work.

This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the paper contains references to papers, conference proceedings and theses/dissertations on the subject that were published between 1977‐1998. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, ferrites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.