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This study aims to enhance the dyeability of polyester fabrics with turmeric natural dyes through plasma and alkaline treatments. The aim is to achieve better color strength in dyed samples without significant changes in their other properties. This is done while the weight loss is kept in a range with no considerable effect on those properties.

The surface of a poly(ethylene terephthalate) fabric was modified using oxygen plasma at a low temperature. The alkaline hydrolysis of that polyester fabric was also done through treating it with an aqueous sodium hydroxide (NaOH) solution. The untreated and treated polyester fabrics were studied for the changes of their physical characteristics such as weight loss, wetting behavior, strength loss, bending length, flexural rigidity and K/S and wash fastness. The samples were treated with plasma and sodium hydroxide and dyed with a turmeric natural dye.

In comparison to the untreated sample, the plasma-treated, alkaline-treated and plasma treatment followed by alkaline hydrolysis polyester experienced 9.3%, 68.6% and 102.3% increase in its color depth as it was dyed with a turmeric natural dye, respectively. The plasma treatment was followed by alkaline hydrolysis. The improvement in the color depth could be attributed to the surface modification.

In this paper, investigations were conducted of the separate effects of plasma treatment and alkaline hydrolysis as well as their synergistic effect on the dyeing of the polyester fabric with a natural dye obtained from turmeric.

This study aims to investigate the effect of the copresence of ferrous (Fe²⁺) ions and sodium dodecyl sulfate (SDS) on the activity of an amylase enzyme during the desizing of greige viscose fabric for potential industrial applications. The removal of starches is an essential step before processing the fabric for dyeing and finishing operations. The authors tend to accomplish it in eco-friendly and sustainable ways.

The experiments were designed under the Taguchi approach, and the results were analyzed using grey relational analysis to optimize the process. The textile properties of absorbency, reducing sugars, bending length, weight loss, Tegawa rating and tensile strength were assessed using the standard protocols. The control and optimized viscose specimens were investigated for certain surface chemical properties using advanced analytical techniques including scanning electron microscopy (SEM), X-ray diffraction (XRD) and thermal gravimetric analysis (TGA).

The results demonstrate that the Fe²⁺ concentration and process time were the main influencing factors in the amylolytic desizing of viscose fabric. The optimized process conditions were found to be 0.1 mm Fe²⁺ ions, 3 mm SDS, 80°C, 7 pH and 30 min process time. The copresence of Fe²⁺ ions and SDS promoted the biodesizing of viscose fabric. The SEM, Fourier transform infrared spectroscopy, XRD and TGA results demonstrated that the sizing agent has efficiently been removed from the fabric surface.

The amylase desizing of viscose fabric in the presence of certain metal ions and surfactants is a significant subject as the enzyme may face them due to their prevalence in the water systems. This could also support the biodesizing and bioscouring operations to be done in one bath, thus making the textile pretreatment process both economical and environmentally sustainable.

The authors found no report on the biodesizing of viscose fabric in the copresence of Fe²⁺ ions and the SDS surfactant under statistical multiresponse optimization. The biodesized viscose fabric has been investigated using both conventional and analytical approaches.

This paper aims to investigate and deliver experimental evidence to establish ball burnishing (BB) as an effective procedure for processing fused filament fabricated parts (FFF). This study, which is a novel contribution to applying BB on FFF parts of materials with different properties, demonstrates the validity of this technology on polymers and provides generalizations for its implementation.

A BB tool has been designed and validated. Statistical models have been used to determine the process parameters that provide the best results. In addition, the process’ impacts on the dimensional accuracy, quality, hardness and mechanical performance of the treated parts under static bending and fatigue testing have been quantified and compared to the untreated samples.

This study shows the best combination of process parameters for two printing orientations which have been decisive in obtaining successful results. These positive results allow stating procedure guidelines and recommendations for use in the industrial environment.

This paper fulfills an identified need to enhance FFF parts' surface and mechanical properties, as more experimental evidence of studies demonstrating this technology's validity in additive manufacturing is yet to be found.

The conventional design method relies on a priori knowledge, which limits the rapid and efficient development of electronic packaging structures. The purpose of this study is to propose a hybrid method of data-driven inverse design, which couples adaptive surrogate model technology with optimization algorithm to to enable an efficient and accurate inverse design of electronic packaging structures.

The multisurrogate accumulative local error-based ensemble forward prediction model is proposed to predict the performance properties of the packaging structure. As the forward prediction model is adaptive, it can identify respond to sensitive regions of design space and sample more design points in those regions, getting the trade-off between accuracy and computation resources. In addition, the forward prediction model uses the average ensemble method to mitigate the accuracy degradation caused by poor individual surrogate performance. The Particle Swarm Optimization algorithm is then coupled with the forward prediction model for the inverse design of the electronic packaging structure.

Benchmark testing demonstrated the superior approximate performance of the proposed ensemble model. Two engineering cases have shown that using the proposed method for inverse design has significant computational savings while ensuring design accuracy. In addition, the proposed method is capable of outputting multiple structure parameters according to the expected performance and can design the packaging structure based on its extreme performance.

Because of its data-driven nature, the inverse design method proposed also has potential applications in other scientific fields related to optimization and inverse design.

This paper aims to investigate the responses of single piles and pile groups due to tunneling-induced ground movements in a two-layered soil system. The analyses mainly focus on the additional single pile responses in terms of bending moment, lateral deflection, axial force, shaft resistance and pile settlement. Subsequently, a series of parametric studies were carried out to better understand the responses of single piles induced by tunneling. To give further understanding regarding the pile groups, a 2 × 2 pile group with two different pile head conditions, namely, free and capped, was considered.

Using the PLAXIS three-dimensional (3D) software, a full 3D numerical modeling is performed to investigate the effects of ground movements caused by tunneling on adjacent pile foundations. The numerical model was validated using centrifuge test data found in the literature. The relevance of the 3D model is also judged by comparison with the 2D plane strain model using the PLAXIS 2D code.

The numerical test results reveal that tunneling induces significant displacements and internal forces in nearby piles. The magnitude and distribution of internal forces depend mainly on the position of the pile toe relative to the tunnel depth and the distance between the pile and the vertical axis of the tunnel. As the volume loss increases from 1% to 3%, the apparent loss of pile capacity increases from 11% to 20%. By increasing the pile length from 0.5 to 1.5 times, the tunnel depth, the maximum pile settlement and lateral deflection decrease by about 63% and 18%, respectively. On the other hand, the maximum bending moment and axial load increase by about 7 and 13 times, respectively. When the pile is located at a distance of 2.5 times the tunnel diameter (Dt), the additional pile responses become insignificant. It was found that an increase in tunnel depth from 1.5Dt to 2.5Dt (with a pile length of 3Dt) increases the maximum lateral deflection by about 420%. Regarding the interaction between tunneling and group of piles, a positive group effect was observed with a significant reduction of the internal forces in rear piles. The maximum bending moment of the front piles was found to be higher than that of the rear piles by about 47%.

Soil is a complex material that shows differently in primary loading, unloading and reloading with stress-dependent stiffness. This general behavior was not possibly being accounted for in simple elastic perfectly plastic Mohr–Coulomb model which is often used to predict the behavior of soils. Thus, in the present study, the more advanced hardening soil model with small-strain stiffness (HSsmall) is used to model the non-linear stress–strain soil behavior. Moreover, unlike previous studies THAT are usually based on the assumption that the soil is homogeneous and using numerical methods by decoupled loadings under plane strain conditions; in this study, the pile responses have been exhaustively investigated in a two-layered soil system using a fully coupled 3D numerical analysis that takes into account the real interactions between tunneling and pile foundations. The paper presents a distinctive set of findings and insights that provide valuable guidance for the design and construction of shield tunnels passing through pile foundations.

Dehydrated bacterial cellulose’s (BC) intrinsic rigidity constrains applicability across textiles, leather, health care and other sectors. This study aims to yield a novel BC modification method using glycerol and succinic acid with catalyst and heat, applied via an industrially scalable padding method to tackle BC’s stiffness drawbacks and enhance BC properties.

Fabric-like BC is generated via mechanical dehydration and then finished by using padding method with glycerol, succinic acid, catalyst and heat. Comprehensive material characterizations, including international testing standards for stiffness, bending properties (cantilever method), tensile properties, moisture vapor transmission rate, moisture content and regain, washing, thermal gravimetric analysis, derivative thermogravimetry, Fourier-transform infrared spectroscopy and colorimetric measurement, are used.

The combination of BC/glycerol/succinic acid dramatically enhanced porous structure, elongation (27.40 ± 6.39%), flexibility (flexural rigidity of 21.46 ± 4.01 µN m; bending modulus of 97.45 ± 18.20 MPa) and moisture management (moisture vapor transmission rate of 961.07 ± 86.16 g/m²/24 h; moisture content of 27.43 ± 2.50%; and moisture regain of 37.94 ± 4.73%). This softening process modified the thermal stability of BC. Besides, this study alleviated the drawbacks for washing (five cycles) of BC and glycerol caused by the ineffective affinity between glycerol and cellulose by adding succinic acid with catalyst and heat.

The study yields an effective padding process for BC softening and a unique modified BC to contribute added value to textile and leather industries as a sustainable alternative to existing materials and a premise for future research on BC functionalization by using doable technologies in mass production as padding.

The application of servo steel struts enables the active control of the excavation-induced deformation in foundation pits. However, there is currently only one design axial force for each servo steel strut, which requires in-situ axial force adjustments based on the experience of site engineers. The purpose of this study is to develop a method for determining the design axial forces of servo steel struts at different excavation steps.

In this study, a hybrid method for determining the design axial forces of servo steel struts in different excavation steps was established based on the combination of the elastic foundation beam model and nonlinear optimisation.

The hybrid method is capable of providing a better set of design axial forces than the original design method. The lateral wall displacement and bending moment could be better controlled. Ordinary steel struts should be prevented from being set between servo steel struts to avoid axial force losses.

The axial forces of the servo steel struts at different excavation steps should be designed to achieve better deformation control effects. Moreover, a well-designed set of axial forces can also reduce the internal forces of the retaining structure.

The hybrid method enables the determination of the design axial forces of servo steel struts at different excavation steps, which can guide axial force adjustments in practical projects.

The aim of the paper is to propose a global, automated and continuous curvature calibration strategy for bending sensors, which is used for the angle feedback control of soft fingers.

In this work, the proposed curvature calibration strategy for bending sensors is based on the constant curvature bending properties of soft fingers. The strategy is to install the bending sensor on the soft finger and use the laser distance sensor to assist calibration, then calculate the relationship between the curvature and the voltage of the bending sensor through geometric conversion. In addition, this work also develops a full set of standard calibration systems and collection procedures for the bending sensor curvature calibration and uses machine learning algorithms to fit the collected data.

First, compared with the traditional calibration methods, the proposed curvature calibration strategy can achieve constant curvature measurement with the advantages of better continuity. Second, using the sensor data obtained by the proposed calibration method as the feedback signal for the soft finger bending angle control, the control effect is better than that of the traditional method.

This work proposes and verifies a global, automated and continuous curvature calibration strategy for bending sensors and is used for the angle feedback control of soft fingers. In addition, this work also develops a full set of standard calibration systems and collection procedures, which can be applied to a variety of flexible bending sensors with a good adaptability.

Tapered steel sections are widely used in house building design due to their structural efficiency and aesthetic appearance. Due to the practical usage of web tapering specifications in the metal building industry, fabrication and material expenses are analyzed to achieve geometric and economic productivity. The purpose of this study is to investigate the effectiveness of utilizing web profiles with openings in reducing the weight of steel beams.

In this paper, the nonlinear analysis of the bending behavior of a tapered steel section with an opening was studied by finite element analysis. The results were then compared with those of the tapered steel section without an opening in terms of displacement and yield moment.

The bending capacity of a tapered steel section was analyzed using finite element analysis. Results showed that the tapered steel section without openings had a higher bending capacity compared to the section with various sizes of web openings. The results also showed that decreasing the number of openings would increase the bending capacity, whereas increasing the size of the opening would decrease it. The difference in the yield moment between the tapered steel section with and without openings was only 15.818%. A total of 60 nonlinear analyses were conducted to investigate the effect of the number and size of web openings, flange thickness and web thickness on the bending behavior. However, this study showed that web opening with octagon shape and 0.6D size of web opening, where D is the depth of section, showed the best section in terms of yield moment and volume reduction compared to other opening size and shape.

It is also found that tapered steel section has better moment resistance in thicker flange and web. The study is valuable for engineers and designers who work with steel structures and need to optimize the performance of tapered steel sections with web openings.

This paper aims to present a kinematics analysis method and statics based control of the continuum robot with mortise and tenon joints to achieve better control performance of the robot.

The kinematics model is derived by the geometric analysis method under the piecewise constant curvature assumption, and the workspace and dexterity of the proposed robot are analyzed to optimize its structure parameters. Moreover, the statics model is established by the principle of virtual work, which is used to analyze the mapping relationship between the bending deformation and the applied forces/torques. To improve the control accuracy of the robot, a model-based controller is put forward.

Results of the experiments verify the feasibility of the proposed continuum structure and the correctness of the established model and the control method. The force deviation between the theoretical value and the actual value is relatively small, and the mean value of the deviation between the driving forces is only 0.46 N, which verify the established statics model and the controller.

The proposed model and motion controller can realize its accurate bending control with a few deviations, which can be used as the reference for the motion planning and dynamic model of the continuum robot.