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Lightweight, open construction cotton knitted fabrics generally do not impart good protection from solar ultraviolet radiation (UVR). As lightweight 100% cotton single jersey is highly cherished for summerwear, it is sine qua non to understand the structural parameters that effectively strike a good balance between UV protection and thermophysiological comfort of the wearer. Relatively heavy fabrics protect from UVR, but comfort is compromised because of waning porosity, increase in thickness and thermal insulation. The purpose of this paper is to engineer knits that will bestow maximum UV protection while preserving the thermophysiological comfort of the wearer.

In total, 27 cotton single jersey fabrics with different areal densities and yarn counts were selected. Ultraviolet protection factor (UPF) was calculated based on the work of Imrith (2022). To précis, the authors constructed a UV box to measure the UPF of fabrics, denoted as UPF_B. UPF_B data were correlated with AATCC 183-2004 and yielded high correlation, R² 0.977. It was concluded that UPF 50 corresponds to UPF_B 94.3. Thermal comfort properties were measured on the Alambeta and water-vapour resistance on the Permetest. Linear programming (LP) was used to optimize UPF_B and comfort. Linear optimization focused on maximizing UPF_B while keeping the thermophysiological comfort and areal density as constraints.

The resulting linear geometrical and sensitivity analyses generated multiple technically feasible solutions of fabrics thickness and porosity that gave valid UPF_B, thermal absorptivity and water-vapour and thermal resistance. Subsequently, an interactive optimization software was developed to predict the stitch length, tightness factor and yarn count for optimum UPF_B from a given areal density. The predicted values were then used to knit seven 100% cotton single jersey fabrics and were tested for UV protection. All seven fabrics gave UPF_B above the threshold, that is, higher than 94.3. The mathematical model demonstrated good correlations with the optimized parameters and experimental values.

The optimization software predicted the optimum UPF_B reasonably well, starting from the fabric structural and constructional parameters. In addition, the models were developed as interactive user interfaces, which can be used by knitted fabric developers to engineer cotton knits for maximizing UV protection without compromising thermophysiological comfort. It has been demonstrated that LP is an efficient tool for the optimization and prediction of targeted knitted fabrics parameters.

The purpose of this paper is to analyze the effects of treatments using chitosan in different degree of deacetylations (DDs) on thermophysiological comfort properties of nylon 6,6/elastane pressure garments using a large skin model hot plate instrumentation to prevent infection and excess sweating during burn scar management for future designs.

Chitosans in different DD (DD 70, DD 81 and nylon 6,6/elastane fabrics in different structures, then the total DD 90) are treated with thermal resistance (R_ct) ((°ΔC)(m²)/W), total heat loss (Q_t or THL) (W/m²), apparent total evaporative resistance ( R e t A ), ((ΔkPa)(m²)/W), apparent intrinsic evaporative resistance ( R e f A ), ((ΔkPa)(m²)/W) and total insulation values (I_t) (clo) were analyzed using the large skin model hot plate instrumentation in comparison with untreated control samples. Antimicrobial activities, washing tests and moisture regain properties were also evaluated.

It is found that chitosan DDs have a significant effect on thermophysiological comfort properties of nylon 6,6 fabrics. A small but statistically significant decrease was observed in thermal resistance (R_ct) (Tog) and isolation (I_t) (clo) properties for higher chitosan DDs and for higher chitosan concentrations for all fabric samples after each treatment. Antimicrobial activity showed a small but statistically significant decrease for all samples with the increase of DD and fabrics treated with lower DD 70 of chitosan showed better antimicrobial activity for all samples. Additionally, fabrics treated with higher DD’s exhibited higher moisture regain.

Treatments with chitosan in different DD and in different concentrations impact the heat and moisture transfer properties of nylon 6,6 fabrics significantly. It is a reference to evaluate the thermophysiological comfort properties of pressure garments for future designs using dry and sweating skin tests while imparting antimicrobial activity with chitosans in different DDs.

The thermophysiological comfort of fabrics is prerequisite as customers covet adequate moisture, heat management-supported and UV protective clothing that measure up to their levels of activities and environmental conditions. Hitherto, scant tasks have been reported with the purpose of engineering both comfort and UV protection simultaneously. From that vantage point, the objective of this work is to develop a model for optimum UPF, air permeability, water-vapour resistance, thermal resistance, thermal absorptivity and areal density of knitted fabrics.

Weft knitted fabrics of various compositions were investigated. UPF was tested using the Labsphere UV transmittance analyser. The FX 3300 (Textest instruments) air permeability tester was used to test air permeability. Thermal comfort and water-vapour resistance were evaluated using the Alambeta and Permetest instruments, respectively. Based on image processing, the porosity was measured. Fabrics thickness and areal density were measured according to standard methods. Furthermore, parametric and non-parametric statistical test methods were applied to the data for analysis.

Linear regression was substantiated by Kolmogorov-Smirnov test. Then multiple linear regression of porosity and thickness together on UPF and comfort parameters were visually depicted by virtue of 3D linear plots. Residual analysis with quantile-quantile and probability plots, advocated the tests using the Shapiro-Wilk test. The result was validated by comparison with experimental data tested. The samples gave satisfactory relative errors and were supported by the z-test method. All tests indicated failure to reject the null hypothesis.

The predictive models were embedded into an interactive computer program. Fabric thickness and porosity are the inputs needed to run the program. It will predict the optimum UPF, areal density and thermophysiological comfort parameters. In a nutshell, knitters may use the program to determine optimum structural parameters for diverse permutations of UPF and thermophysiological comfort parameters; scilicet high UV protection together with low thermal insulation combined with low water-vapour resistance and high air permeability.

To evaluate the effectiveness of ventilation systems in outdoor jackets, two jackets were purchased and modified, one made of PTFE laminated fabric and the other made of polyurethane coated fabric. Six male subjects undertook exercise routines simulating fell walking while wearing these jackets. The skin temperature at four different locations and the amount of perspiration generated during exercise were recorded for analysis. The experimental results were analysed using two‐ way analysis of variance. From the analysis it was found that during the exercise the design of the pit zip openings, especially with pit zip openings at both sleeve and side seams, in a jacket has an effect on thermal regulation, limiting the rate of temperature increase; however, during rest it is the fabric that plays the more important role. The results for the period of exercise suggest that the provision of ventilation at appropriate positions in the jacket could contribute considerably to heat loss irrespective of the use of breathable fabrics.

The purpose of this paper is to integrate a thermophysiological human body model into a CFD simulation to predict the dry and latent body heat loss, the clothing, skin and core temperature, skin wettedness and periphery blood flow distribution. The integration of the model allows to generate more realistic boundary conditions for the CFD simulation and allows to predict the room distribution of temperature and humidity originating from the occupants.

A two-dimensional thermophysiological body model is integrated into a CFD simulation to predict the interaction between the human body and room environment. Parameters varied were clothing insulation and metabolic activity and supply air temperature. The body dry and latent heat loss, skin wettedness, skin and core temperatures were predicted together with the room air temperature and humidity.

Clothing and metabolic activity were found to have different level of impact on the dry and latent heat loss. Heat loss was more strongly affected by changes in the metabolic rate than in the clothing insulation. Latent heat loss was found to exhibit much larger variations compared to dry heat loss due to the high latent heat potential of water.

Unlike similar studies featuring naked human body, clothing characteristics like sensible resistance and vapor permeability were accommodated into the present study. A method to ensure numerical stability of the integrated simulation was developed and implemented to produce robust and reliable simulation performance.

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.

In this study the effect of the aminofunctional silicone softeners on fabrics’ heat and moisture transport properties has been investigated by means of Alambeta and Permetest instruments. The silicone treated PES blended fabrics are warmer to the touch, but less comfortable as regards their reduced water‐vapour permeability. The finishing stage of the fabrics has considerable influence on their thermal touch sensation and water‐vapour permeability.

The purpose of this paper is to analyze the influence of underwear on the microenvironment of human clothing.

Based on the basic laws of energy and mass conservation, the paper combined the theory of heat and mass transfer to establish the simulation of the influence of underwear on human thermal reaction in microclimate and prediction model of human thermal reaction law.

The impact on the microenvironment affected by tighter underwear is less than the effect of loose underwear and computational flow dynamics (CFD) can accurately predict the thermal reaction parameters’ values of the human body.

It can be effectively used for the prediction of heat exchange between human body and environment in high-temperature environment and human thermophysiological parameters, and overcomes the individual differences of human experiments and the danger and repeatability of high-temperature environmental experiments.

The purpose of this study is to analyze the question “In what order of magnitude does the comfort and performance improvement lie with the use of a cooling vest for construction workers?”.

The use of personal cooling systems, in the form of cooling vests, is not only intended to reduce the heat load, in order to prevent disruption of the thermoregulation system of the body, but also to improve work performance. A calculation study was carried out on the basis of four validated mathematical models, namely a cooling vest model, a thermophysiological human model, a dynamic thermal sensation model and a performance loss model for construction workers.

The use of a cooling vest has a significant beneficial effect on the thermal sensation and the loss of performance, depending on the thermal load on the body.

Each cooling vest can be characterized on the basis of the maximum cooling power (Pmax; in W/m²), the cooling capacity (Auc; in Wh/m2) and the time (tc; in minutes) after which the cooling power is negligible. In order to objectively compare cooling vests, a (preferably International and/or European) standard/guideline must be compiled to determine the cooling power and the cooling capacity of cooling vests.

It is recommended to implement the use of cooling vests in the construction process so that employees can use them if necessary or desired.

Climate change, resulting in global warming, is one of the biggest problems of present times. Rising outdoor temperatures will continue in the 21st century, with a greater frequency and duration of heat waves. Some regions of the world are more affected than others. Europe is one of the regions of the world where rising global temperatures will adversely affect public health, especially that of the labor force, resulting in a decline in labor productivity. It will be clear that in many situations air conditioning is not an option because it does not provide sufficient cooling or it is a very expensive investment; for example, in the situation of construction work. In such a situation, personal cooling systems, such as cooling vests, can be an efficient and financially attractive solution to the problem of discomfort and heat stress.

The value of the study lies in the link between four validated mathematical models, namely a cooling vest model, a thermophysiological human model, a dynamic thermal sensation model and a performance loss model for construction workers.

Choosing the adequate garment for sports practice in adverse weather conditions, either cold or hot, is an aspect of great influence on activity performance. The purpose of this paper is to describe how the Institute of Biomechanics of Valencia has developed a methodology which allows assessing the fit of the garment to the real situation of use by evaluating its influence in the thermoregulatory response of the human body.

Under controlled environmental conditions and at fixed activity levels, two shirts are tested in the laboratory. Eight subjects performed a test which consisted of six phases of different activity level in two conditions (25°C/50 percent RH and 10°C/60 percent RH). Throughout the test, physiological parameters of the thermal response as well as work load indicators are registered. Skin temperature at three different locations (chest, arm, and thigh), microclimate variables in some areas of subject‐garment interface (in armpit and upper back) and heart rate are measured continuously. Six samples of sweat are also collected regularly from dorsal region during the test to estimate the sweating rate and the loss of salts. Weight loss is also checked before and after performing the test to estimate the dehydration level. Subjects will be asked during the test about humidity and temperature perception on the body as a whole or by different zones. The results allowed measuring a significant influence of the shirt in skin temperature. Therefore, the methodology developed for studying of the user‐product interaction through the assessment of the thermophysiological response and the subjective perception allows recommending the comfort ranges for each piece of garment as well as indicating those work load and environmental conditions for which the influence of garment on user's performance is optimal.

The user‐product interaction through the assessment of the thermophysiological response and the subjective perception allows recommending the comfort ranges for each piece of garment as well as indicating those work load and environmental conditions for which the influence of garment on user's performance is optimal.

Choosing a suitable garment for sports practice in adverse weather conditions, either cold or hot, is an aspect of great influence on activity performance and this paper presents new results.