Research On The Structure Design Of Straight Tube Skirt Based On The Allocated Ratio Of Waist-darts’ Volumes

The ratio of waist dart volume is an important structural parameter to determine the fit of skirt.Considering the coverage rate of wearing objects,the waist darts of the Bunka basic skirt pattern is allocated in a fixed proportion without reflecting the ratios of dart volume corresponding to the waist shapes.In this study,the waist shape subdivisions and corresponded total waist darts volume and the ratio of each waist dart were obtained based on the characteristic factors of lower body shape extractions related waist darts volumes and ratios,and the discriminant model of waist shape features was established.It provides a theoretical reference for the individual structural design of waist darts on basic straight skirt pattern.A total of 34 anthropometric items were collected for120 female college students aged between 18 and 25 in central China by means of 3D scanning and photo measurement.Among them,the photo measurement included 7 angle items and 27 characteristic items of body surface were included and measured on overlapped graphics of waist characteristic sections.The comparison of the control variables between this sample and the national standard160/84 A female body size showed that the average hip circumference of subjects was slightly larger than the national standard.The comparison results of waist dart ratio with Bunka basic blocks of skirt showed that,the waist dart ratio showed significant difference except for dart 2.The correlation analysis results showed that the waist forward inclination(β),waist forward inclination(YTQ)and hip protrusion(AB)were significantly correlated with the ratio of anterior and posterior lumbar dint(1,2,4 and 5),respectively,indicating that the waist forward inclination and hip protrusion were closely related to the ratio of waist dint.There was a significant correlation between the total waist saving and the lateral waist receiving value(YTC)with r = above 0.8,indicating that the lateral waist shape was the main factor affecting the total waist saving.Furthermore,principal component analysis extracted three principal components with characteristic values greater than 1,and the cumulative contribution rate reached 87.144%,which were lumbar forward factor,waist shape factor and lateral waist shape factor.Among them,the lumbar forward factor and the lateral waist shape factor were Closely related to the ratio of anterior and posterior waist saving and total waist saving.According to the results of principal component analysis(PCA),the typical indexes of the front and side of the waist were screened,and the front and side of the waist were subdivided into 3 categories by K-means clustering.Nine composite types of waist shape reflecting the difference of waist shape were obtained by cross combination,and the corresponding configuration of waist saving amount was obtained.The Bayes discriminant analysis was used to obtain the discriminant function of waist morphological features.The cross validation showed that the positive discriminant rate of front and side features was more than 80%.Finally,the efficiency of Bayes discriminant functions for the waist features recognizing was verified by 18 female college students as new subjects.There has no significant difference between the measured values of new samples and the discriminant values by the paired sample T test.Then,three new samples with different waist shapes were selected randomly to try on straight skirts with corresponding waist dart ratios using CLO3 D.All of Bunka basic straight skirt of each subject showed that the side stitches inclined to the buttocks,the side waist was bulged,and the side folds often appeared,the adjusted basic straight skirt has reasonable and straight side seams,no obvious slant pleats,and high waist fit by contrast.