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The purpose of this paper is to provide the details of developments to research works in the distribution characteristics of the air gaps within firefighters’ clothing and research methods to evaluate the effect of air gaps on the thermal protective performance of firefighters’ clothing.

In this paper, the distribution of air gaps within firefighters’ clothing was first analyzed, and the air gaps characteristics were summarized as thickness, location, heterogeneity, orientation and dynamics. Then, the evaluation of the air gap on the thermal protective performance of fighters’ clothing was reviewed for both experimental and numerical studies.

The air gaps within clothing layers and between clothing and skin play an important role in determining the thermal protective performance of firefighters’ protective clothing. It is obvious that research works on the effects of actual air gaps entrapped in firefighters’ clothing on thermal protection are comparatively few in number, primarily focusing on static and uniform air gaps at the fabric level. Further studies should be conducted to define the characteristic of air gap, deepen the understand of mechanism of heat transfer and numerically simulate the 3D dynamic heat transfer in clothing to improve the evaluation of thermal protective performance provided by the firefighters’ clothing.

Air gaps within thermal protective clothing play a crucial role in the protective performance of clothing and provide an efficient way to provide fire-fighting occupational safety. To accurately characterize the distribution of air gaps in firefighters’ clothing under high heat exposure, the paper will provide guidelines for clothing engineers to design clothing for fighters and optimize the clothing performance.

This paper is offered as a concise reference for researchers’ further research in the area of the effect of air gaps within firefighters’ clothing under thermal exposure.

The purpose of this paper is to determine the effects of clothing ease and body postures on the size and distribution of the air gap as well as the body coverage with the clothing.

Visual and quantitative analyses were conducted using a 3D body scanner and Geomagic Software. The air gap size and clothing area factor (f_cl) in three test coverall and seven selected postures were calculated and compared.

The results indicated that both the clothing ease and body postures had a strong effect on the air gap and clothing coverage, especially the more complex the postures, the wider the range of influence. Nevertheless, these effects varied over body regions, being stronger at the lower body than the upper body. The air gap size at the left side of the body was generally larger than the right side. It was also found that the clothing coverage was linearly correlated with the air gap size and could be employed as an indicator to evaluate clothing protective capabilities.

The findings suggested that greater attention should be paid to the protection and flexibility at the lower body and asymmetrical distribution of the air gap should be considered in the future air gap modeling.

The outcomes provided useful information to improve the protective clothing and develop more realistic air gap models to simulate the heat and mass transfer.

The purpose of this paper is to determine the effect of flash fire exposure on the mechanical properties of single-layer thermal protective clothing.

The full-scale flame manikin tests were performed to simulate flash fire exposure. Two typical fire-resistant fabrics were investigated. The manikin was divided into seven body parts and the specimens meeting the requirements of tensile and tear strength standards were sampled. Fabric thickness, mass per unit area, tensile strength and tear strength were measured and analyzed.

The results revealed the significant influence of heat flux on both of tensile and tear strength. However, the regression analysis indicated the low R² of the liner models. When the tensile and tear strength retention were reorganized based on the body parts, both of the multiple linear regression models for tensile and tear strength showed higher R² than the one-variable linear regressions. Furthermore, the R² of the multiple linear regression model for tear strength retention was remarkably higher than that of the tensile strength.

The findings suggested that greater attention should be paid to the local part of human body and more factors such as the air gap should be considered in the future thermal aging of firefighters’ clothing studies.

The outcomes provided useful information to evaluate the mechanical properties of thermal protective clothing and predict its service life.

Personal protective assembles protect searchers and rescuers from potential hazards when they enter the earthquake disaster field. Since the earthquake rescue work is risky and complicated, the corresponding protective clothing should meet with the protective, functional and comfort performance demands. The purpose of this paper is to discuss the design principles of this kind of protective clothing and present a design model based on the principles.

In this study, the requirements of the protective clothing were investigated in terms of environment, human and clothing. Then the design principles were analyzed by the hierarchy method in four aspects: protection, comfort, ergonomics and compatibility. Design approaches were also investigated in accordance with the design principles in three hierarchies.

Key design points were summarized in the selection of the shell fabrics and linings, clothing styles, constructions and specifications. Also, the overall design methodology of the protective clothing for earthquake rescue members was established.

This paper provided a theoretical basis and design model for the development of earthquake search and rescuers’ clothing.

This study aims to investigate the heat transfer mechanism of the uniforms used by people working in hot, humid and windy environments. Furthermore, the effectiveness of an opening structure added to the armpit of the uniforms in improving thermal comfort was comparatively examined.

A set of uniforms was tested with the opening at the armpit alternatively zipped or unzipped. Thermal manikin and human tests were performed in a climatic chamber simulating the specific environmental conditions, including wind speeds at four levels (0.15, 0.5, 2, 4 m/s) and relative humidities at two levels (50 and 85%). Static and dynamic thermal insulations of clothing (I_T) were examined by the thermal manikin tests. The human bodies' thermal responses, including heart rates (HR), eardrum temperatures (T_e), skin temperatures (T_sk) and subjective perceptions, were given by the human tests.

Special mechanisms of heat transfer in the specific uniforms used in tropical monsoon climates were revealed. Reductions on I_T were caused by the movement of the human body and the environmental wind, and the empirical equations would underestimate this reduction. The opening at the armpit was able to prompt more heat transfer under dynamic condition, with reducing the I_T by 11.8%, lowering the mean T_sk by 0.92°C, and significantly improving the subjective perceptions (p < 0.05). The heat exhaustion was alleviated with lowering the T_e by 0.32°C.

This study managed to improve the thermal performance of uniforms for workers under unforgiving conditions. The evaluation and design methods introduced by this study provided practical guidance for similar products with strict dress codes and cost control requirements based on the findings from thorough product tests and analysis.

In this study, the authors explore the association between employee education level and the efficiency of corporate investment using data from a sample of Chinese listed firms during the period from 2011 to 2018. By examining the impact of education on investment efficiency, the authors' study provides valuable insights that contribute to a deeper understanding of the underlying economic mechanisms related to education.

The authors conduct multivariate regression analyses to examine the relationship between investment efficiency (following Richardson, 2006) and the level of employee education, along with a series of control variables. To ensure the reliability of the authors' findings, the authors subject the their results to a comprehensive set of robustness tests, such as a staggered difference-in-difference (DiD) regression approach, an instrumental variable (IV) method and the use of alternative employee education level and investment efficiency measurements.

The findings offer compelling evidence that higher levels of education have a positive impact on firms' investment efficiency, and this effect remains robust across various model specifications and endogeneity considerations. Moreover, the influence of education is more pronounced in firms that prioritize employee training, maintain effective internal communication and offer attractive financial rewards. Furthermore, the results suggest that the relationship between education and investment efficiency is influenced by the firms' business nature and competitive environment. Factors such as business complexity, labor intensity and business location also play a role in shaping the impact of education on investment outcomes.

The study emphasizes the crucial role of education in influencing investment decisions and performance within firms. By delving into this previously unexplored area, the authors' research contributes to the existing literature, establishing that the level of employee education is a significant determinant of corporate investment efficiency. This valuable insight has substantial implications for firms aiming to enhance their investment decision-making processes and overall performance. Understanding the positive impact of education on investment efficiency can empower organizations to leverage their human capital effectively and achieve better investment outcomes, ultimately contributing to long-term success and competitiveness in the market.

The purpose of this study is to determine the temperature ratings of infant bedding.

Mathematical models were developed for predicting temperature ratings of infant bedding for all age groups based on the thermal balance equation. These models were validated by the published physiological data and the baby manikin tests. The air temperature was compared with the predicted temperature rating, and the skin temperature of infant or baby manikin was used to explain the validation results.

The models had higher prediction accuracy, especially for the infant bedding with uniformly distributed thermal insulation. The results showed that an increase of 1 clo in thermal insulation caused a decrease of 4.2–6.0 °C in temperature rating. The slope of the model reduced with the increasing month-age, indicating that an older infant had a lower temperature rating than a younger infant.

Suggestions were given for caregivers that younger infants ought to be covered with more bedding than adults; however, older infants were expected to require less bedding.

The outcomes provided scientific guidelines on the selection of bedding for infants at a particular room temperature to ensure the health and safety of infants.

The purpose of this paper is to study heat and steam transfer in a vertical air gap and improve thermal protective performance of protective clothing under thermal radiation and hot steam.

An experiment-based model was introduced to analyze heat and moisture transfer in the vertical air gap between the protective clothing and human body. A developed test apparatus was used to simulate different air gap sizes (3, 6, 9, 12, 15, 18, 21 and 24 mm). The protective clothing with different air gap sizes was subjected to dry and wet heat exposures.

The increase of the air gap size reduced the heat and moisture transfer from the protective clothing to the skin surface under both heat exposures. The minimum air gap size for the initiation of natural convection in the dry heat exposure was between 6 and 9 mm, while the air gap size for the occurrence of natural convection was increased in the wet heat exposure. In addition, the steam mass flux presented a sharp decrease with the rising of the air gap size, followed by a stable state, mainly depending on the molecular diffusion and the convection mass transfer.

This research provides a better understanding of the optimum air gap under the protective clothing, which contributes to the design of optimum air gap size that provided higher thermal protection against dry and wet heat exposures.

The ergonomic performance of protective clothing for earthquake disaster search and rescue team members is significant for its protective performance. The paper aims to discuss these issues.

By experimental simulations of the rescue tasks, an evaluation system for the protective clothing in both static and dynamic conditions was designed and established in this study. In static evaluation, motion capture system was used to measure the ranges of motions. The mobility was analyzed by the comprehensive evaluation method. In dynamic experiments, three types of rescue tasks were simulated for ergonomic evaluation. The results were analyzed based on the multi-levels joint evaluation method.

It was shown that the established evaluation system could meet well with the requirements of the ergonomic evaluation.

Fuzzy comprehensive evaluation method is an effective tool in ergonomic evaluation of clothing. The newly designed coverall and suit are of better ergonomic performance compared with the in-service clothing.

After China's accession to the WTO, different formats of retailing outlets have emerged and competition within China's apparel retail market has become keener. This paper presents a comparison research on four influential retailing outlets in the current Shanghai apparel retail market: upscale shopping centers, modern shopping malls, joint discount superstores (joint ventures with foreign retail giants), and manufacturers' wholly‐owned flagship stores (factory outlets). Corresponding to each retailing outlet, Plaza 66, Grand‐Gateway Mall, Carrefour Store in Quyang Road, and Youngor Flagship Store in Nanjing Road are studied, with an investigation of apparel brands covered by each. The results identify the four retailing outlets' characteristics, and future prospects in the Chinese apparel retail market are discussed.