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Jintu Fan

Publications and source records attributed to Jintu Fan.

6 recordsLinked to original sources

Prediction of clothing thermal insulation and moisture vapour resistance of the clothed body walking in wind.

Clothing thermal insulation and moisture vapour resistance are the two most important parameters in thermal environmental engineering, functional clothing design and end use of clothing ensembles. In this study, clothing thermal insulation and moisture vapour resistance of various types of clothing ensembles were measured using the walking-able sweating manikin, Walter, under various environmental conditions and walking speeds. Based on an extensive experimental investigation and an improved understanding of the effects of body activities and environmental conditions, a simple but effective direct regression model has been established, for predicting the clothing thermal insulation and moisture vapour resistance under wind and walking motion, from those when the manikin was standing in still air. The model has been validated by using experimental data reported in the previous literature. It has shown that the new models have advantages and provide very accurate prediction.

Equipment Design↗

Interactions of the surface heat and moisture transfer from the human body under varying climatic conditions and walking speeds.

The surface heat and moisture transfer from the human body are normally characterized by the thermal insulation and moisture vapor resistance, which are important parameters in environmental engineering. In the past, due to the limitation of measurement technology, simultaneous measurement of these two parameters was not possible and hence there is a lack of clear understanding on the interaction of surface heat and moisture transfer. In this paper, through the experimental measurements on a newly developed sweating/non-sweating fabric manikin (named WALTER) under varying climatic conditions and "walking" speeds, we show that the surface thermal insulation is little affected by moisture transfer. The surface moisture vapor resistances measured under isothermal conditions tend to be greater than those measured under non-isothermal conditions, especially when the wind velocity is less than 2.0m/s. The Lewis Relation holds under non-isothermal conditions, but should be corrected under isothermal condition when the wind velocity is small.

Climate↗

Perceived body size affected by garment and body mass index.

This study investigated the effect of garment size on perceived body size. The perceived body sizes of nine Chinese men, with Body Mass Index between 17.0 and 37.1 kg/m(2), wearing five sizes of white T-shirts were assessed using Thompson and Gray's Nine-figural Scale. Garment sizes on perceived body sizes were different for those of different Body Mass Index. A backpropagation neural net model was used to model the nonlinear relationship between the perceived body size and the body's BMI, body chest girth, and garment ease (difference between garment and body chest girth). When the BMI was less than 20, wearing larger-sized T-shirts tended to increase perceived body size. For large chest sizes and for taller persons (BMI of 20 to 28) large garments made the wearer look thinner. However, for small persons (BMI of 20 to 28) effect of garment size was relatively small. Obese persons (BMI of > 28), wearing garments too tight or too loose were perceived as larger. Minimum perceived body size was found for garment ease of 2 to 3 cm.

Adult↗

Visual perception of surface wrinkles.

To study the relationship between visual perception of magnitude of wrinkles and geometrical parameters of surfaces, four potentially relevant parameters of the surface profile were considered: the variance (sigma2), the cutting frequency (Fc), the effective disparity curvature (Dce) of the wrinkled surface over the eyeball distance of the observer, and the frequency component of the disparity curvature (Dcf). Analysis of garment seams with varying amount of pucker showed that, while the logarithm for each of these four parameters has a strong linear relationship with the visually perceived magnitude of wrinkles, following the Fechner Law, the effective disparity curvature (Dce) and the frequency component of the disparity curvature (Dcf) with visual perception appeared stronger. This modeling may be an objective method for measuring magnitude of surface wrinkles.

Clothing↗

New functions and applications of walter, the sweating fabric manikin.

In this paper, latest developments on Walter, a sweating fabric manikin, are reported. These include the improved simulation of "walking motion", the design and construction of an automated water supply, and real-time measurement of evaporative water loss and regulation of "skin" temperature through the regulation of the pumps inside the manikin body. Testing of commercial garment ensembles showed that the measurement of thermal insulation and moisture-vapour resistance of clothing is very reproducible with the coefficient of variation being generally less than 5%. It was also shown that, in addition to the thermal insulation and moisture-vapour resistance, the percentage of moisture accumulation within clothing is a very useful parameter of clothing comfort. The improved manikin has been used to investigate the effects of walking motion on thermal insulation and evaporative resistance of clothing. The trend of the effects of walking speed up to 1.13 m s(-1) for the nude manikin and when it was wearing garments of different sizes are reported.

Clothing↗

Garment sizes in perception of body size.

This paper reports an experimental investigation of the effect of garment size on perceived body size. The perceived body sizes of three Chinese men (thin, medium, and obese build) wearing different sizes of white T-shirts were assessed using Thompson and Gray's 1995 Nine-figural Scale in 1 (thinnest) to 9 (obese) grade and a newly-proposed method. Within the limit of commercially available T-shirt sizes, for thin and medium persons, perceived body sizes are bigger when wearing T-shirts of larger sizes. For an obese person, however, wearing a large size T-shirt tends to make him look thinner. The study also showed that the newly proposed comparative method is more reliable in comparing body size perception but without measuring the magnitude of the change in body-size grade. The figural scale and the comparative method can be complementary.

Adult↗