Two kinds of cotton fibers cultivated by different methods were measured and the mechanical properties of these fibers were compared with the mechanical properties of cotton yarns made of organic cotton fiber and non-organic cotton fiber. In this study, the mechanical properties of single cotton fibers and cotton yarns the authors measured and the moduli were calculated by assuming that the cross-section of the cotton fiber is elliptical. It was also found that the strains and stresses of breaking point of organic cotton fibers were larger than those of non-organic cotton fibers. Cotton fibers cultivated in different areas were then examined and it was found that the moduli of cotton fibers cultivated in the northern or southern hemisphere (USA and Australian cottons in this study) were very similar, and the yarn properties for yarns made from cotton fibers from both areas were also very similar. However, the yarn consisting of a mixture of cottons in the northern and southern hemispheres had larger strain, torsional stiffness and hysteresis. It was concluded that the deterioration of fibers consisting of a mixture of cotton contributes to the yarn properties, because the rules of surface orientation differ for cotton fibrils cultivated in the northern and the southern hemisphere as shown in Onogi’s study (Textile Res. J.66, 406-410 (1996)).

This study aimed to validate the effectiveness of the Articulation Motion Assessment System (AMAS), a joint kinematic evaluation system, for clinical applications. AMAS enables synchronised measurement using neurophysiological indicators, overcoming laboratory setting limitations. We compared AMAS-based ankle joint kinematic evaluations, particularly the sagittal and frontal plane angles, with two-dimensional (2D) motion analysis to determine the validity and reliability of AMAS. Both AMAS and 2D motion analysis reliably detected significant differences in angles within the sagittal and frontal planes. Correlation analysis revealed a significant moderate-to-strong correlation between the AMAS and the conventional method of 2D motion analysis, proving the measurement validity of the AMAS (ρ = 0.53–0.77 for sagittal plane angles; ρ = 0.46–0.72 for frontal plane angles). The average root mean squared error (RMSE) was significantly lower in AMAS (10.90 ± 2.93° for sagittal plane angles; 13.44 ± 1.09° for frontal plane angles) than in the inertial sensor-based three-dimensional (3D) motion analysis. Reliability analysis revealed high reliability of measurements (intraclass correlation coefficients (ICC) ≥ 0.76). However, the Bland–Altman analysis identified a slightly lower fixed bias, which was observed as a characteristic of each measurement system. The AMAS accurately detects ankle joint angles without being constrained by measurement environment limitations. Synchronised measurements using neurophysiological indicators potentially contribute to understanding ankle joint control mechanisms and developing rehabilitation strategies.

The aim of this study was to clarify the relationship between tactile sensation and physical properties of instrument panel material by applying the method of objective fabric hand evaluation. Physical properties of samples were measured, and subjective evaluation of tactile sensation was conducted by forty-four subjects. The subjects were divided into two clusters based on the subjective evaluation results, and the differences in the tactile evaluation criteria for each cluster were discussed. The results of the multiple regression analysis indicated that softness and elastic feel were related to compressional properties, while roughness was strongly related to surface roughness property. Surface roughness, softness, and elastic feel contributed significantly to the total tactile evaluation. Emboss patterns influenced surface roughness, and types of material polymer affected compressional properties. Furthermore, the two clusters differed in their evaluation of the appropriate roughness and softness, indicating differences in preferences.

The purpose of this study was to clarify the relationship between the physical properties of cotton towels and subjects' preferences. 52 towel samples were measured for physical properties and subjectively evaluated by 59 subjects. Subjects were classified into clusters based on their subjective evaluations, and multiple regression analysis was used to examine the relationship between tactile and physical properties and differences in preferences. In results, subjects were divided into three clusters; the cluster (a) that emphasized fullness, the cluster (b) that valued fluffiness, and the cluster (c) that attached importance to smoothness. For the cluster (a), thickness had the greatest influence on preference. For the cluster (b) and (c), when towels had similar thickness, compressional resilience RC and mean deviation of friction coefficient MMD had the most influence on the evaluation of preference, but when the thickness were different, the cluster (b) emphasized sensations based on compressional energy WC and the cluster (c) emphasized sensations based on RC and MMD. These results will contribute to manufacturing that meets diverse preferences in the future.

Fiber-to-fiber recycling must be promoted to achieve sustainability in the textile industry. Mixed fiber materials cause significant issues in recycling, making accurate sorting essential for recycling. Garments may contain internal materials called interlinings, which are wrapped in the outer fabric and are not visible from the garment’s surface. This study proposes a non-destructive method for detecting interlinings in garments using active infrared (IR) thermography. Numerical simulations showed that the presence, thickness, and material of the interlining affected the cooling behavior. Fourier analysis of the surface temperature curves revealed that an increased interlining thickness leads to slower cooling and a greater phase lag, enabling the identification of interlining characteristics from thermal responses.