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The induction of geological disasters is predominantly influenced by the dynamic evolution of the stress and plastic zones of the multilayer rock formations surrounding deep-rock roadways, and the behaviours and mechanisms of high in situ stress are key scientific issues related to deep-resource exploitation. The stress environment of deep resources is more complex owing to the influence of several geological factors, such as tectonic movements and landforms. Therefore, in practical engineering, the in situ stress field is in a complex anisotropic three-dimensional state, which may change the deformation and failure law of the surrounding rock. The purpose of this study is to investigate the tunnelling-induced stress and plastic evolution causing instability of multilayered surrounding rock by varying three-dimensional in situ stresses.

Based on data from the Yangquan Coal Mine, China, a finite difference model was established, and the elastic-plastic constitutive model and element deletion technology designed in the study were analysed. Gradual tunnelling along the roof and floor of the coal seam was used in the model, which predicted the impact tendency, and compared the results with the impact tendency report to verify the validity of the model. The evolutions of the stress field and plastic zone of the coal roadway in different stress fields were studied by modifying the maximum horizontal in situ stress, minimum horizontal in situ stress and lateral pressure coefficient.

The results shown that the in situ stress influenced the stress distribution and plastic zone of the surrounding rock. With an increase in the minimum horizontal in situ stress, the vertical in situ stress release area of the roof surrounding rock slowly decreased; the area of vertical in situ stress concentration area of the deep surrounding rock on roadway sides decreased, increased and decreased by turn; the area of roof now-shear failure area first increased and then decreased. With an increase in the lateral pressure coefficient, the area of the horizontal in situ stress release area of the surrounding rock increased; the area of vertical in situ stress release area of the roof and floor surrounding rock first decreased and then increased; the area of deep stress concentration area of roadway sides decreased; and the plastic area of the surrounding rock and the area of now-shear failure first decreased and then increased.

The results obtained in this study are based on actual cases and reveal the evolution law of the disturbing stress and plastic zone of multilayer surrounding rock caused by three-dimensional in situ stress during the excavation of deep rock roadways, which can provide a practical reference for the extraction of deep resources.

Plans a wear simulation of assembled textile structures by sewing, basing the study on the submission of standardized seams carried out on 40 wool fabrics and blends containing wool to a series of 20 cycles of fatigue, including: washing, drying and submission to a static mechanical load under determined characteristics and steam ironing. Seams in the warp and weft directions were performed on. Examines the following parameters: fabric strength and elongation to break; seam strength and slippage; seam efficiency; seams’ opening limit and both the modulus at 1mm and at break, along the fatigue cycles. Analyses results obtained in function of the seam directions and fatigue cycles.

In the cardboard package production process, the cardboard roll and the cardboard bottom are joined in the seaming process. During the process, the cardboard is plastically deformed and damage to the cardboard surface can occur. The purpose of this study was to optimise the macro-geometrical parameters of the seaming chuck in order to minimise the cardboard damage during the seaming process.

The influences of geometrical properties of the seaming chuck on the seaming force were investigated using numerical investigations and statistical analysis.

A force-displacement model was established, which enabled the optimisation of the seaming chuck geometry for a reduction of the seaming force.

Results from the present study imply that for tribological optimisation, not only the surface properties such as roughness and frictional response but also the macro-geometrical features of the actual mechanical components should be considered, as these can considerably affect the contacting forces and consequently the friction within the tribosystem.

Based on the performed analyses, a new seaming chuck was manufactured, which is currently undergoing testing in the real production process and is providing improved performance in terms of seam quality as compared to the benchmark.

In the present work, a systematic approach towards the use of statistical methods in tribological optimisation projects is provided for a use case applying a combination of numerically calculated and experimentally measured values.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-02-2020-0065/

This paper aims to propose the artificial neural network (ANN) and regression models for the estimation of the thread consumption at multilayered seam assembly stitched with lock stitch 301.

In the present study, the generalized regression and neural network models are developed by considering the fabric types: woven, nonwoven and multilayer combination thereof, with basic sewing parameters: sewing thread linear density, stitch density, needle count and fabric assembly thickness. The network with feed-forward backpropagation is considered to build the ANN, and the training function trainlm of MATLAB software is used to adjust weight and basic values according to the optimization of Levenberg Marquardt. The performance of networks measured in terms of the mean squared error and the layer output is set according to the sigmoid transfer function.

The proposed ANN and regression model are able to predict the thread consumption with more accuracy for multilayered seam assembly. The predictability of thread consumption from available geometrical models, regression models and industrial empirical techniques are compared with proposed linear regression, quadratic regression and neural network models. The proposed quadratic regression model showed a good correlation with practical thread consumption value and more accuracy in prediction with an overall 4.3% error, as compared to other techniques for given multilayer substrates. Further, the developed ANN network showed good accuracy in the prediction of thread consumption.

The estimation of thread consumed while stitching is the prerequisite of the garment industry for inventory management especially with the introduction of the costly high-performance sewing thread. In practice, different types of fabrics are stitched at multilayer combinations at different locations of the stitched product. The ANN and regression models are developed for multilayered seam assembly of woven and nonwoven fabric blend composition for better prediction of thread consumption.

Knitted fabrics have been widely used in a wide range of applications such as apparel industry. Since these fabrics are continuously subjected to the long-term tensile stresses or tensile creep in real conditions, investigation of viscoelastic behavior of sewn knitted fabrics would be important especially at the seamed area. The paper aims to discuss this issue.

A lockstitch machine was used to produce sewn samples by knitted fabric. Factors such as stitch per inch (SPI), thread tension and thread type were variables of the model. Tensile creep tests under constant load of 200 N were conducted, and creep compliance parameter D(t) of samples was obtained as a response variable. A successive residual method (SRM) was also used to characterize viscoelastic properties of sewn-seamed fabrics.

The instantaneous elastic responses of the seamed samples were less than those of the neat fabric (fabric with no seam). An increase in sewing thread strength increases the instantaneous elastic response of the sample. SPI and thread tension have an optimum value to increase E₀. High tenacity polyester thread, due to its higher elastic modulus, caused a larger E₀ than polyester/cotton thread in sewn knitted fabric. Characteristics of seam including sewing thread type, SPI and sewing tension have significant influence on T₀. Sewn-seamed fabric by high modulus thread shows less viscous strain T₀ than the neat fabric (fabric with no seam). Viscous strain T₀ decreases as SPI changes from 8 to 4 and/or 12. SPI and thread tension have an optimum value to increase the viscous strain T₀. E1 is the same for optimum seamed fabric and fabric sample but T1 is about two times greater for seamed fabric. Retarded time for creep recovery increases by sewing process but characteristics of seam have significant influence on E1 and T1. All sewn knitted fabric samples used in this study could be described by Burger’s model, which is a Maxwell model paralleled with a Kelvin one.

This paper is going to use a different method named successive residuals to model the creep behavior of seamed knitted fabric. On the whole, this paper paved a way to obtain viscoelastic constants of sewn-seamed knitted fabrics based on different sewing parameters such as the modulus of elasticity of the sewing thread, SPI and sewing thread tension.

Examines the tenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

Even though modern welding technology has improved, initial defects on weld notches cannot be avoided. Assuming the existence of crack-like flaws after the welding process, the stage of a fatigue crack nucleation becomes insignificant and the threshold for the initial crack propagation can be used as a criterion for very high cycle fatigue whereas crack growth analysis can be applied for the lifetime estimation at lower number of cycles. The purpose of this paper is to present a mechanism based approach for lifetime estimation of welded joints, subjected to a multiaxial non-proportional loading.

The proposed method, which is based on the welding process simulation, thermophysical material modeling and fracture mechanics, considers the most important aspects for fatigue of welds. Applying worst-case assumptions, fatigue limits derived by the weight function method can be then used for the fatigue assessment of complex welded structures.

An accurate mechanism based method for the fatigue life assessment of welded joints has been presented and validated.

Compared to the fatigue limits provided by design codes, the proposed method offers more accurate lifetime estimation, a better understanding of interactions between welding process and fatigue behavior. It gives more possibilities to optimize the welding process specifically for the considered material, weld type and loading in order to achieve the full cost and weight optimization potential for industrial applications.

This paper aims to define the dominating factors having influence on the quality of the seam by sewing of fine fabrics and their optimum values.

Ten factors defining a seam's quality are chosen on the base of literary research. There was a check for concurrence of specialists' opinions, as the Spearman's coefficient of concordance was determined. A designed experiment with variation of the first three of the arranged factors was made. Mathematical models for the tensile and the aesthetical properties of the seam were devised, and also optimization made.

A classification of the properties, defining seam's quality, is made. A cause‐effect diagram of Ishikawa with aiming parameter – quality of the seam – has been developed. On the basis of a survey the factors that have a great deal of influence on it are presented. Mathematical models for seam's strength, elongation and smoothness are produced by changing the following factors: straining of the upper thread, size of the needle and load on the pressing foot are worked out. Received models are optimized.

The research was conducted using a sewing‐machine class 301. Received results and conclusions refer to seams made from base material – fabric from PES and sewing thread from 100 percent PE.

Optimum values have been established for the straining of the upper thread, the size of the needle and the load on the pressing foot by sewing of fabric from synthetic silk with mass applicable machines, needles, and sewing threads.

The research has been done in several directions: systemizing the seam's properties for evaluation of its quality and the factors defining it, inquiry into the significance of the different factors and implementation of a designed experiment. Consultations were made with a broad circle of specialists and these results are given in visual systems (schemes and graphs).

The properties of polyester/cotton (PC) fabric after chemical treatments as lining in woolen suits has been investigated, as the purpose of this paper is to study the influence of different finishing agents and their concentration on the properties of PC fabrics.

Three different chemical finishes such as anti-slip finish, softener and moisture management finish were applied to currently popular 80/20 PC pocketing fabric at three different concentration levels. A total of 60 seams were produced from 2/1 twill woolen shell fabric and chemically treated lining. Six important tests defining comfort and seam’s quality of lining fabric were chosen, namely, seam strength, seam slippage, stiffness, drape, water vapor transmission (WVT), abrasion resistance to study its properties and testing were done as per standardized test methods.

Chemical treatments affect the properties of PC fabric used as lining significantly in terms of seam strength, seam slippage, WVT and abrasion resistance. Among the three applied chemical finishes softener, at 20, 40 and 60 g/l, was found to be the best choice to make PC fabric suitable in terms of seam performance, durability, drape and comfort for use lining in suits with economic advantage.

The paper contributes to understanding the properties of relatively cheap 80/20 PC pocketing fabric used as lining in a suit.

The purpose of this paper is to establish a strain prediction model of mining overburden deformation, to predict the strain in the subsequent mining stage. In this way, the mining area can be divided into zones with different degrees of risk, and the prevention measures can be taken for the areas predicted to have large deformation.

A similar-material model was built by geological and mining conditions of Zhangzhuang Coal Mine. The evolution characteristics of overburden strain were studied by using the distributed optical fiber sensing (DOFS) technology and the predictive model about overburden deformation was established by applying machine learning. The modeling method of the predictive model based on the similar-material model test was summarized. Finally, this method was applied to engineering.

The strain value predicted by the proposed model was compared with the actual measured value and the accuracy is as high as 97%, which proves that it is feasible to combine DOFS technology with machine learning and introduce it into overburden deformation prediction. When this method was applied to engineering, it also showed good performance.

This paper helps to promote the application of machine learning in the geosciences and mining engineering. It provides a new way to solve similar problems.