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1 – 10 of over 158000THE paper reviews the problem of the influence of the walls of a closed tunnel in increasing the velocity in the neighbourhood of a model under test. It is shown that, for a…
Abstract
THE paper reviews the problem of the influence of the walls of a closed tunnel in increasing the velocity in the neighbourhood of a model under test. It is shown that, for a perfect fluid, considerations of continuity suffice to establish an exact value of the mean interference velocity for any cross‐section of the tunnel. This mean interference velocity is expressed in terms of the perturbation velocity which would be caused by the same model in the absence of the walls. The linearized theory of subsonic compressible flow is applied and it is shown that the interference velocity for a small two or three dimensional model is increased in proportion to l/β3, where β=√(l—M2) and M is the Mach number. Interference caused by a body with a long parallel middle body, the influence of the wake from a model and of the boundary layer on the tunnel walls are briefly considered.
Jun Zhang, KyoungOk Kim and Masayuki Takatera
The purpose of this paper is to propose a size-changing method with three-dimensional (3D) garment modeling for various body sizes considering vertical body proportions in…
Abstract
Purpose
The purpose of this paper is to propose a size-changing method with three-dimensional (3D) garment modeling for various body sizes considering vertical body proportions in addition to horizontal dimensions, while preserving the silhouette and ease of the original garment.
Design/methodology/approach
Cross-sectional dimensions and shapes of one dress form (the standard body) and jacket bodice were obtained by 3D scanning. The authors calculated horizontal multiplication factors of the relationship between the standard body and jacket bodice, and vertical body proportions. A target dress form was deformed using multiplication factors and vertical body proportions to construct a garment model that fitted the dress form. The method was verified using three different dress forms. The bodices of the jackets were compared with those obtained without adjusting vertical proportions.
Findings
Employing the proposed method, jacket bodices were made and fitted on target bodies while preserving the original shape. Jackets bodices made without considering vertical proportions had many wrinkles and deformed shape and poor fit around the bust line owing to the different vertical proportions. The vertical proportion is thus an important factor in the 3D garment modeling of garments of different size fitted on a body.
Research limitations/implications
The proposed method is a new size-changing or grading method for a bodice that preserves the original silhouette.
Originality/value
The proposed modeling method allows the construction of jacket bodice models and jackets of different size considering vertical body proportions. The method is applicable when making individually tailored garments or ready-to-wear garments for different targets.
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Youngsook Cho, Naoko Okada, Hyejun Park, Masayuki Takatera, Shigeru Inui and Yoshio Shimizu
In order to mass‐customize clothes, it is essential to consider individual body shape using computerized 3D body models. This paper describes the development of an interactive body…
Abstract
Purpose
In order to mass‐customize clothes, it is essential to consider individual body shape using computerized 3D body models. This paper describes the development of an interactive body model that can be altered with individual body shape for the purpose of computerized pattern making.Design/methodology/approach – For altering perimeter and length for contouring individual body shapes, a cross‐sectional line model is proposed arranged at regular intervals. This model is easy for controlling body shape and also for calculating length and perimeters. Shape control lines (SCL) are used to modify the shape of the model in order to adjust the model to represent different body shapes. SCL are used to modify the perimeter of the cross‐sectional line by scaling method with different center position and scaling ratio in a horizontal direction.Findings – In order to investigate whether virtual body models can be adequately substituted for real physical models, the perimeter and cross‐section areas of shape control lines were compared, which resulted in an agreement ratio of over 93 percent. This fact supports the adaptability and potential usefulness of the body model.Originality/value – This research makes it possible for customers to modify the body model to match their own body shape during internet or catalogue shopping; it can also enable apparel manufacturers to communicate with their customers by describing the body model to fit on the screen while in the ordering process.
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In Hwa Kim, Hyunsook Han and Su-Jeong Hwang Shin
The purpose of study is to investigate effectiveness of pattern technique in relation to the use of anthropometric references for drafting women's basic bodice patterns by…
Abstract
Purpose
The purpose of study is to investigate effectiveness of pattern technique in relation to the use of anthropometric references for drafting women's basic bodice patterns by assessing characteristics of pattern formation, quantification of wearing ease on the transverse plan and actual ease distribution on body forms.
Design/methodology/approach
Three pattern drafting techniques were analyzed, which have different frequency of using direct body measurements for pattern formulation. Ease quantification and wearing ease distribution were evaluated on the two different body forms: a young female body and a heavy woman body. Women's basic bodice patterns were drafted with YUKA CAD and virtually draped on the two body forms with CLO 3D. Rapidform was used to evaluate garment appearance. Areal ease and its distribution were assessed. A deviation map was used for wrinkle analysis.
Findings
Compared to the pattern formation derived from few anthropometric references, patterns using sufficient anthropometric references provided overall better fit for the different body forms. Ease distribution without considering body arcs was found to be a cause of garment fit problems. Patterns with little or no ease caused transverse fine wrinkles and skewed side seams. Pattern techniques those used linear equations caused problems on the bust because the formulation could not reflect bust protrusions in relation to the body torso shape differences.
Originality/value
This study revealed characteristics of pattern formulae and linear equations in relation to anthropometric references and body shapes. The findings may be effective in developing algorithm of the customized pattern formation in the industry.
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The purpose of this study is to investigate cross‐cultural differences between American and Japanese college students' body type under/overestimation regarding their own bodies…
Abstract
Purpose
The purpose of this study is to investigate cross‐cultural differences between American and Japanese college students' body type under/overestimation regarding their own bodies within the framework of self‐construal theory.
Design/methodology/approach
Information from 137 American college students and 160 Japanese college students was collected in using a survey method. Their height, body weight, gender, and self‐estimated body types from three different options (underweight, normal weight, and overweight) was collected in order to assess the relationship between self‐estimated and real body types of these participants. The real body type based on one's body mass index and the self‐estimated body type were compared for each participant.
Findings
Japanese students were found to be more in the underweight category and less in the overweight category than American students. It was also found that Japanese students, and female students in general, were more likely to overestimate their body types and American students, and male students in general, were more likely to underestimate their body types.
Research limitations/implications
The present study used self‐report survey method and should be considered a pilot study. In future research, the height and weight of participants should actually be measured to obtain more reliable data. Future research should investigate other possible psychological factors for creating different body types between different cultures.
Originality/value
The present study was the first cross‐cultural study regarding body type under/overestimation regarding their own bodies between American and Japanese college students.
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Xiangyu Du, Junying Yang, Fei Gao, Xiaoming Han and Linlin Su
This paper aims to reveal the effects of the copper third body on different copper matrix friction materials with a novel experimental way called “exogenous powder.”
Abstract
Purpose
This paper aims to reveal the effects of the copper third body on different copper matrix friction materials with a novel experimental way called “exogenous powder.”
Design/methodology/approach
An accurate adding device of exogenous copper powder was designed to control the flow rate. The tribological properties with and without exogenous copper powder were investigated by a pin-on-disc tribometer during dry sliding.
Findings
Experimental results indicate that the Cu addition tends to increase the friction coefficient. For pure Cu material, the exogenous copper third body exhibits poor fluidity on the friction surface, causing serious adhesive wear on the friction interface. For the Cu 90% + 10% Gr material, the plasticity of exogenous copper powder may intensify the deformation of the third body of the surface, presenting layered accumulation distribution. For the pure Cu and Cu 95% + 5% SiO2 material, the Cu addition makes the composition and density of the third body uneven in the direction of depth.
Originality/value
The role of the copper component on different materials is revealed from a new perspective, and the relationship between the third body structure and the friction properties is explored.
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Peter R.M. Jones, Peng Li, Katherine Brooke‐Wavell and Gordon M. West
Presents a standard data format for describing and interpolating 3‐D human body shapes from data collected by a 3‐D body scanner. The body data were treated as a series of…
Abstract
Presents a standard data format for describing and interpolating 3‐D human body shapes from data collected by a 3‐D body scanner. The body data were treated as a series of horizontal cross‐sections. Each cross‐section was described by 16 data points. The 3‐D surface can be calculated by interpolating between these sections. This procedure allowed editing and manipulation of raw scanned data, as well as substantial data reduction. Horizontal cross‐sections of the body were chosen to correspond to particular anatomical surface landmarks, rather than distances from a reference point. Hence, each data element described a particular anatomical location, irrespective of body shape and size. This feature allowed comparison and averaging of 3‐D shapes, greatly enhancing the application of 3‐D scanned data. The standard data format allows 3‐D scanned data to be transferred into CAD/CAM systems for automated garment design and manikin manufacture.
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The research is made in view of the anthropometry information obtaining problem in garment MTM on the network mode. The purpose of this paper is to obtain anthropometry…
Abstract
Purpose
The research is made in view of the anthropometry information obtaining problem in garment MTM on the network mode. The purpose of this paper is to obtain anthropometry information in a convenient and detailed way in garment MTM on the network mode.
Design/methodology/approach
First of all, 24 main measurement sizes of 427 young females are collected to constitute the measurement database. The database is used as background data support of the system. The images are captured to simplify the way of inputting the anthropometry information to the system. Through the 2D feature sizes extracted from body image and the basic dimensions provided by customer input to the system, so that to gain the body sample which is closest to the customer body type through query matching in the database. The detailed anthropometry information of the closest sample is used to describe the customer. The human body measurement database and the technology of body image acquisition are used to extract the feature sizes to achieve obtaining the anthropometry information in a convenient and detailed way.
Findings
Through query matching to the customer in a test, the body sample closest to the customer is gained, and the matching error rate is 0.0132. In the end, some customer samples are input to test the system, in order to verify the effectiveness of system functions. The matching error rates of five body types are gained all less than 0.006. The error is small, and the matching result is ideal.
Research limitations/implications
The size of database established in the paper can be increased constantly in the future to obtain the more accurately matching result.
Practical implications
The research of anthropometry information obtaining system in garment MTM on the network mode is the basis to achieve gaining the anthropometry information in a convenient and detailed way.
Social implications
Applying the established system of human body measurement information acquisition in this paper, it can achieve to obtain the detailed measurement information of customer through a convenient way, combining the method of human body parameter model establishment in the existing research, it can achieve the complete network tailored mode with detailed measurement information acquisition and 3D virtual fitting functions. And it can provide the most convenient experience and the most ideal garment MTM effect to the customer. This mode can be forecast to be an ideal form of garment MTM on the network in the future.
Originality/value
The anthropometry information obtaining system is the important part of garment MTM system on the network mode. It should be applied to the network mode and can obtain the detailed measurements for garment MTM. In this paper, the human body measurement database and the technology of body image acquisition are used in order to extract the feature size to obtain the anthropometry information in a convenient and detailed way.
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Yu Chen, Xianyi Zeng, Michel Happiette, Pascal Bruniaux, Royer Ng and Winnie Yu
The purpose of this paper is to present recent work for optimizing the estimation of ease allowance of a garment using fuzzy logic and sensory evaluation.
Abstract
Purpose
The purpose of this paper is to present recent work for optimizing the estimation of ease allowance of a garment using fuzzy logic and sensory evaluation.
Design/methodology/approach
The current method first generates a number of fuzzy models each corresponding to one specific key body part and one specific wearer's movement and then aggregates all the values of ease allowance generated from these fuzzy models using the ordered weighted averaging (OWA) operator. The aggregated ease allowance takes into account geometric measures on all representative human bodies, comfort sensations of wearers related to all movements or actions and different styles of trousers (tight, normal and loose). The weights of the OWA operator can be used to adjust the compromise between the style of garments and the comfort sensation of wearers. The related weights of the OWA operator are automatically determined according to designer's linguistic criteria characterizing the relationship between wearer's movements and the features of the garment to be designed.
Findings
Based on the optimized values of ease allowance generated from fuzzy models related to different key body positions and different wearer's movements, the authors obtain a personalized ease allowance, permitting to further improve the wearer's fitting perception of a garment. The effectiveness of the method has been validated in the design of trousers of jean type. It can also be applied for designing other types of garment.
Originality/value
Integration of wearer's body shapes and human comfort in the design of personalized garments.
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Young Sook Cho, Takuya Komatsu, Masayuki Takatera, Shigeru Inui, Yoshio Shimizu and Hyejun Park
This paper aims to describe the development of an interactive body model that can be altered to match individual body perimeter, postures and depth for the purpose of computerized…
Abstract
Purpose
This paper aims to describe the development of an interactive body model that can be altered to match individual body perimeter, postures and depth for the purpose of computerized pattern making.
Design/methodology/approach
Construction of the posture and depth adjustable body model requires the extraction of ten points, adjustment of coordinate points, linking of points by spline curves, control of section lengths and selectability of three hip types. Front to back depth of the model is adjusted by scaling ratio.
Findings
Good results were achieved in modelling back shapes, such as flat shape and stoop shape, and of modelling various hip shapes, such as flat shape and protruding shape. Also the presented body model is able to accurately simulate individual depth of bust, waist and hips. Silhouette comparison between the fully adjusted virtual body model and real body shapes shows an almost perfect match. A primary dialog for altering perimeter, length and depth, and a posture dialog for controlling back and hip shapes was developed.
Originality/value
By making fine adjustments to posture and depth, it is possible to make patterns which result in clothing that not only fits well, but also exhibits other desirable properties. This system could, therefore, be seen as a major step forward in pattern making.
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