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The purpose of this paper is to optimise parameters of digital image analysis to investigate the deformation behaviour of woven sample and to detect the onset and variation of wrinkling that occurs due to bias‐tensioned fabric buckling.

Using models of predescribed shape, the relationship between the digitized gray scale intensities and wrinkles of the surface are analysed and conditions of specimen illumination and filtering procedures are chosen.

It is proposed to convert acquired images to binary to record the onset of buckling and to estimate critical buckling parameters of stretched woven samples. The threshold value is determined as mean value of approximated histogram of stretched specimen centre line. It is defined that profile curve and gray scale disperse presented by parameter CV can be used to obtain additional information and to compare behaviour of different samples during bias tension.

Proposed image analysis technique allows detection of the onset of buckling wave formation and evaluation of surface waviness changes in woven samples different in colour and weave type tension. However, the behaviour of fabric samples with sharp multicoloured and complicated patterns cannot be assessed by gray scale imaging.

The proposed approach can be adjusted to investigate different wrinkling problems – buckling during simple shearing or picture frame test, seam puckering, draping.

The purpose of this paper is to test whether household preferences satisfy the assumption of base-independence, to examine the effects of household income on equivalence scales and thereby food consumption economies of scale and to examine how far conventional poverty rates require adjustment when scale economies in food consumption are taken into consideration.

To achieve these aims, the authors use a Pendakur (1999) adaptation of the test of base-independence, and income dependent Engel (1895) equivalence scales.

In Sri Lanka, the hypothesis of base-independence is rejected: the equivalence scales increase with household income both at the national and the sectoral level, that is urban, rural and estate sectors. This suggests that low-income households enjoy greater scale economies. After adjusting for scale economies, urban, rural and estate poverty headcount ratios decline by 3.2, 8.8 and 13.7, respectively, while at the national level the decline is about 8.3.

The results are based on the assumption that all of the adults in the households have identical tastes, irrespective of their gender and age. Furthermore, the survey data exclude three districts in the northern province of Sri Lanka due to resettlement activities took place after the civil war.

Higher scale economies among the poor imply that poverty among low-income households is overstated when using traditional measures of poverty rates.

The novelty of this paper is that it provides insights on the effect of income on food consumption economies of scale and implications of this phenomenon on poverty estimates in the context of a developing country like Sri Lanka.

The soil water retention curve (SWRC) and unsaturated hydraulic conductivity (UHC) are crucial indices to assess hydraulic properties of porous media that primarily depend on the particle and pore size distributions. This study aims to present a method based on the discrete element model (DEM) and the typical Arya and Paris model (AP model) to numerically predict SWRC and UHC.

First, the DEM (PFC^3D software) is used to construct the pore and particle size distributions in porous media. The number of particles is calculated according to the AP model, which can be applied to evaluate the relationship between the suction head and the moisture of porous media. Subsequently, combining critical path analysis (CPA) and fractal theory, the air entry value is applied to calculate the critical pore radius (CPR) and the critical volume fraction (CVF) for evaluating the unsaturated hydraulic conductivity.

This method is validated against the experimental results of 11 soils from the clay loam to the sand, and then the scaling parameter in the AP model and critical volume fraction value for many types of soils are presented for reference; subsequently, the gradation effect on hydraulic property of soils is analyzed. Furthermore, the calculation for unbound graded aggregate (UGA) material as a special case and a theoretical extension are provided.

The presented study provides an important insight into the relationship between the heterogeneous particle and hydraulic properties by the DEM and sheds light on the directions for future study of a method to investigate the hydraulic properties of porous media.

This study aims to evaluate Netemeyer and colleagues' much cited financial well-being scale in Brazil and India and compare responses from different demographics. It also compares the results using two analysis techniques, item response theory (IRT) and confirmatory factor analysis (CFA).

A total of 994 survey responses from Brazil and 1,081 from India were collected. IRT and CFA models were used to analyse the data.

The results demonstrate the two-dimensional structure of the financial well-being scale and show that different items are differentially useful in measuring the construct across different groups. These findings may support the scale's future refinement and use in applied studies that will target specific groups (e.g. males, females, younger respondents and older respondents).

This study serves as an example to others who can explore the advantages of IRT over classical test theory methods to assess the psychometric properties of scales aimed at measuring latent constructs of interest in the field of marketing.

The correct diagnosis of financial well-being is important to guide interventions by governments and non-governmental entities, as well as by financial institutions interested in better understanding individuals.

The authors show how the identification of the characteristics of scale items provided by the IRT technique allows for a better understanding of its properties and how it can be improved.

The purpose of this paper is to investigate the use of nanoindentation with a Berkovich indenter as a method of extracting equivalent stress‐strain curves for the base metal and the welded zone of a friction stir welded aluminum alloy.

Friction stir welding is a solid‐state joining process, which emerged as an alternative technique to be used in high strength alloys that were difficult to join with conventional joining techniques. This technique has a significant effect on the local microstructure and residual stresses combined with deformation. Nano‐ and micro‐indentation are the most commonly used techniques to obtain local mechanical properties of engineering materials. In order to test the reliability of nanoindentation technique and to connect nanoscale with macroscale, the indentation hardness‐depth relation established by Nix and Gao was applied on the experimental values.

The predictions of this model were found to be in good agreement with classical hardness measurements on AA 6082‐T6 aluminum alloy. Also, finite element method provides a numerical tool to calculate complex nanoindentation problems and in correlation with gradients theories forms a well‐seried tool in order to take into account size effects.

By studying this alloy, the paper reviews fundamental principles such as stress‐strain distribution, size effects rise during nanoindentation and the applicability of finite element method, in order to take into account these issues.

THE word “Nomography” means literally the art of drawing up laws in proper form.

The purpose of this paper is to identify optimum operating parameters, namely, link-length and vertex angle, for producing virtual clothing prototypes for the purpose of pattern flattening.

Commercially available physically based simulation and flattening engines were utilized to carry out the computational part of this study. Two separately developed 3D garment templates were used for the creation of virtual garments in the form of a triangulated mesh and later for pattern unwrapping by taking differential link-lengths and vertex angles into account to ascertain their effects on the mesh quality and on the ultimate pattern flattening process.

It has been found that a link-length between 10 and 15 mm and a vertex angle between 120° and 160° are optimum for the virtual clothing prototyping process.

The findings of this study can universally be applied to simplify the tasks of virtual clothing prototyping and pattern unwrapping using commercial software packages.

Previously, there has not been any guidance available for the selection of specific operational parameters to promote 3D garment design.

This paper reports experiments with a term weighting model incorporating relevance information in which it is assumed that index terms are distributed dependently. Initially this model was tested with complete relevance information against a similar model which assumes index terms are distributed independently. The experiments demonstrated conclusively that index terms are not independent for a number of diverse document collections. It was concluded that the use of relevance information together with dependence information could potentially improve retrieval effectiveness. As a result of further experiments the initial strict dependence model was modified and in particular a new relevance‐based term weight was developed. This modified dependence model was then used as the basis for relevance feedback, i.e. with partial relevance information only, and significant increases in retrieval effectiveness were achieved. The evaluation method used in the feedback experiments emphasized the effect of the feedback on documents which the potential user would not previously have seen. Finally the incorporation of relevance feedback in an operational system is considered and in particular it is argued that if high recall searches are required, relevance feedback based on the modified dependence model may be superior to the widely used Boolean search.