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Industrial dye effluent causes significant risks to the environment. The present study was focused on photocatalytic degradation of the dye Direct Red 28 using a ternary composite of graphitic carbon nitride, TiO2, and polyorthoanisidine (g-C3N4/TiO2/POA), prepared by in-situ oxidative polymerization o-anisidine. The synthesized composite g-C3N4/TiO2/POA properties were characterized using different analytical techniques. X-ray diffraction (XRD) results revealed the prominent pattern of TiO2 and g-C3N4 in the composite peak at 2θ° while Fourier transform infrared (FTIR) results provided the confirmation peaks for g-C3N4/TiO2/POA and POA at 1,110 cm−1 and 1,084 cm−1 for C-O-C ether. Scanning electron microscopy (SEM) demonstrated an increase in the average size of the composite up to 428 nm. The energy-dispersive X-ray spectroscopy (EDX) spectrum provided the weight percentages of the C, O, and Ti in the composite were 8.5%, 45.69%, and 45.81%, respectively. The photocatalytic degradation of Direct Red 28 dye under UV irradiation using a composite showed that 86% Direct Red 28 dye was degraded by a 30 mg/L dose of g-C3N4/TiO2/POA in 240 min at pH 2. After four consecutive cycles, the utilized composite showed 79% degradation of Direct Red 28, demonstrating the stability and effectiveness of the g-C3N4/TiO2/POA photocatalyst. The high reusability and efficiency of the g-C3N4/TiO2/POA composite are due to increased light absorption range and reduced e−/h+ recombination rate in the presence of g-C3N4 and POA.

This study refines a single-layer Feed-Forward Neural Network (FFNN) for the treatment of textile dye wastewater, concentrating on percentage decolorization (%DEC) and percentage chemical oxygen demand (%COD) reduction. The optimized neural network configuration comprises four input and one output neuron, fine-tuned based on the mean squared error (MSE). The training phase demonstrates a consistent MSE decline, reaching its lowest at epoch 209 for %DEC and epoch 34 for %COD, with corresponding MSEs of $1.799 \times 10^{-5}$ and $ 1.4 \times 10^{-3} $, respectively. The maximum absolute errors for %DEC and %COD were found to be $ 4.0787 $ and $ 2.4486 $, while the mean absolute errors were $ 0.4821 $ and $ 0.7256 $, respectively. In contrast to second-degree polynomial regression, the FFNN model exhibits enhanced predictive accuracy, as indicated by higher $ R^2 $ values of $ 0.99363 $ for %DEC and $ 0.99716 $ for %COD, and reduced error metrics.

Abstract A variety of industries employ synthetic azo dyes. However, the biosphere is being damaged by the unused/leftover azo dyes, which pose a danger to all living things. Therefore, treating them to shield the environment from the potential harm of azo dyes is crucial. Bio-sorption is a cheap and effective mode for eliminating toxic dyes in the environment. The current work focused on synthesizing magnesium oxide (MgO) nanoparticles using an aqueous leaf extract of neem (Azadirachta indica). The XRD and SEM analyses of MgO nanoparticles indicated the crystalline nature of MgO nanoparticles with a cubic structure, and the size was around 90–100 nm. FTIR analysis showed the presence of a stretching frequency peak at 550 cm−1, confirming the Mg–O bond. The surface analysis revealed the cluster form of the synthesized nanoparticles. The UV–visible absorption peak for MgO nanoparticles was found at 294 nm and band gap of 4.52 eV. In order to eliminate the Reactive Red 195 dye, MgO nanoparticles were used. At pH 4, 40 °C, 0.02% dye concentration, and 0.003 g/L catalyst amount, the highest degree of decolorization (91%) was seen. Decreased total organic carbon (TOC) and the chemical oxygen demand (COD) percent were 84.33% and 81.3%, respectively. The proposed mechanism of target dye degradation was also investigated. MgO NPs were found to be effective in their catalytic behavior toward the degradation of Reactive Red 195 dye up to five cycles with almost no change in their catalytic activity.

We investigate fluid flow and heat transfer in a channel obstructed by nail-shaped hurdles under forced convection using the Finite Difference Method. Due to the absence of an analytical solution, numerical techniques are employed. The channel is geometrically transformed into a rectangular configuration using curvilinear coordinates. Elliptic grid generation is used to discretize the domain. The Navier–Stokes equations are reformulated through the vorticity stream function formulation, and the Finite Difference Method incorporates a coordinate transformation approach. Effects of Reynolds numbers between (20≤Re≤600), Prandtl numbers (0.71,17.1), and nail spans (0.1≤h≤0.7) on velocity, temperature profiles is studied. Local and Average Nusselt numbers on Nail-shaped hurdle are also calculated. The observed maximum Nusselt numbers are 13.49,27.83, and 11.86 at Ra=600,Pr=7.1, and h=0.1, respectively Results show that higher Reynolds and Prandtl numbers increase Nusselt numbers, enhancing heat transfer. Narrower nail spans improve heat transfer efficiency.

The Matrix converters (MCs) are widely used in a large number of applications such as Aircraft, Submarines, and AC drives. In these applications, because of the many chances of occurrence of a critical fault that leads to a halt of the system, and due to the failure of power electric switches, the MC operations can be compromised and there is a fear of burning of the components caused by the whole system shutdown. Therefore, a Fault-Tolerant Control System (FTCS) is extremely necessary for the continued operations of the Three-Phase Matrix Converter (TPMC) to improve the reliability and productivity of the system under faulty conditions. In this paper, an advanced FTCS is proposed based on detection, and dual hardware redundancy for TPMC. Two types of faults are injected into the system to observe the performance of the proposed system: internal open circuit faults on switches and external short circuit faults at the load side. A Fault Detection and Isolation (FDI) unit is used to detect and isolate the faulty switches using Artificial Neural Networks (ANN), and dual hardware redundancy in the switches has been proposed for fault tolerance. In case of external fault, a load-side fault detector is implemented using ANN. The simulation results in MATLAB/Simulink environment show the accurate and stable working of TPMC under faulty conditions, and hardware-in-the-loop is implemented with STM32-Nucleo-F103RB board to verify open circuit fault results. The proposed dual redundant FTC with FDI unit offers an excellent solution for the continued performance of TPMC which ultimately enhances the reliability of the system.

2D woven auxetic fabrics (AF) developed by weave design modification provide a continuous, commercial, and low-cost manufacturing process for high strength and stable auxetic structures. However, AFs developed by previous methods have a highly folded surface, which is problematic in printing, laminating, and stitching. For the first time, we studied the auxeticity in a few yarn-based auxetic structures, which provides a uniform surface texture. Reentrant honey-comb geometry was chosen to fabricate auxetic woven fabrics, as such geometry shows the best auxetic nature. Different parameters of auxetic geometry were optimized based on their mechanical response using the statistical tool: gray relational analysis (GRA). The mechanical properties of AFs were compared with conventional (3/1 twill woven) non-auxetic fabric (NAF), having the same specifications. The smaller unit cell (3E) with a reorientation area of 4P showed optimum auxeticity and mechanical properties. The optimized auxetic structure showed superior mechanical properties as compared to conventional fabric. GRA grade of optimized AF was 67.3% higher than the NAF. Most importantly, the tensile strength was 23% higher for optimized AF structure. The bidimensional energy dissipation ability of the AF provides a key advantage in the superior mechanical response.

Textile auxetic materials with negative Poisson’s ratio (NPR) have potential applications in protective textile, filtration, and energy absorbance. However, cotton core-spun based auxetic textile is rarely investigated. In this study, cotton core-spun (Lycra)-based helical auxetic yarn (HAY) was developed, and the effects of core filament linear density on the auxetic behavior were studied. Core-spun cotton yarns of 8/1 Nec containing core filament (180, 260, and 420 D) were developed. Then, these core-spun yarns were wrapped with 50 D Dyneema filament at 393 twist/m to make the HAY. The diameter, NPR, and tensile strength of HAY were increased with increasing linear density of Lycra filament. Image analysis of HAY containing 420 D Lycra showed 57% diameter increase with the change in axial strain from 0 to 15 mm. The maximum auxetic behavior with NPR of −3.97 and tensile strength of 26.71 cN/tex was observed in 420 D Lycra-based HAY. This study proved that the cotton core spun-based HAY can be produced with significant auxetic properties for practically potential use in wearable protective textiles.

Dual-core yarns, containing two filaments within the core of the yarn, have gained increasing commercial and research interest recently, especially in denim manufacturing. The use of multi-components in dual-core yarns allows for tailoring the properties of the yarn and denim fabric. The type of filaments and fibers and their surface characteristics play a role in fiber-to-fiber cohesion within yarn structure. However, little has been reported regarding the effect of different filaments on the properties of dual-core yarns. The objective of this study was to investigate the effect of three different filaments, T400, polyester flat (PET flat) and polyester textured (PET textured) as well as two yarn structures, siro versus non-siro, on tensile, elastic and other properties of dual-core yarns at same twist level and linear density of the yarn. The results showed that the siro spun dual-core yarn containing T400 exhibited 25% higher tenacity compared with yarns containing other filaments. However, the plastic deformation of the yarn containing PET flat filament, having a higher initial modulus, was at a relatively lower level compared with T400 and PET textured. Overall, the siro yarn structure showed lower imperfections and higher tenacity compared with the non-siro yarn structure. The dual-core yarn containing T400 showed a higher level of moisture wicking compared with other filaments which can add to the comfort properties but a similar hairiness level. The findings of this study suggest that the use of a filament with a higher initial modulus can improve the stretch and recovery behavior of the dual-core yarns.

Sustainable packaging solutions are of paramount importance in addressing the environmental challenges posed by conventional non-biodegradable materials. This study addresses this critical need by introducing a novel approach to crafting antimicrobial biodegradable polymer films. Leveraging the benefits of polyvinyl alcohol (PVA) as a base material, combined with corn-starch (CS) and mint extract (ME), these films offer a compelling synergy of eco-friendliness, antimicrobial efficacy, and mechanical strength. The antimicrobial property was imparted by adding mint extract, and boric acid (BA) was added as a cross-linker for better mechanical properties. All process was done by solution casting method followed by mechanical stirring. After 7 days, starch-PVA blend showed 50% weight loss; however, after adding mint extract, the action of microbes was reduced, and a 50% reduction in weight was observed after 12 days. The excellent mechanical properties were achieved by adding 10% aqueous solution of BA as a cross-linker. The confirmation of BA in the blend was done by the Fourier transform infrared spectroscopy (FTIR). Differential scanning calorimetry (DSC) was used to check the thermal properties of the films. Antimicrobial results showed that mint extract was resistant to staphylococcus aureus bacteria. These biodegradable films offer a multifaceted solution, aligning with sustainability objectives, showcasing antimicrobial potential, and demonstrating mechanical robustness. As such, they hold promise for a diverse array of applications, particularly in the realm of environmentally conscious food packaging. In the pursuit of greener alternatives, these films stand as a testament to innovative materials engineering that harmonizes functionality with ecological responsibility.

This study addresses environmental concerns related to sugarcane biomass as an industrial fuel source by exploring its potential for textile applications. Bagasse undergoes sequential alkali-H _2 O _2 treatment, followed by varying concentrations of silicone softener (50 g l ^−1 − 100 g l ^−1 − 150g l ^−1 ). The goal is to enhance fiber fineness and softness. Comprehensive physical and chemical characterization reveals significant alterations in treated fibers, impacting surface morphology, crystallinity, linear density, and moisture regain. Results indicate a decline in fiber linear density from 59.47tex to 48.84tex, thus improved fineness, moisture regain initial from 6.9% to 4.7%, reduced crystallinity, and enhanced mechanical strength with silicone softener treatment. Treated fibers show promise as a sustainable alternative to conventional cotton, emphasizing the importance of sugarcane biomass for eco-friendly textile manufacturing.

This study focuses on developing and characterizing multifunctional composites based on the diglycidyl ether of bisphenol-A (DGEBA) epoxy matrix. The aim is to enhance fire resistance and electrical conductivity properties for applications in various fields. To achieve this, aluminum tri-hydroxide (ATH) was incorporated as a flame retardant (FR) agent, while polyaniline (PANI) was added to impart electrical conductivity. The composites were categorized into three groups: the first containing flame retardant (FR), the second containing PANI for conductivity, and the third containing both PANI and FR for combined effects. E 60-FP emerged as the optimal multifunctional composite, exhibiting superior mechanical properties among the tested formulations. Thermogravimetric analysis (TGA) results provided valuable insights into the thermal stability of E 60-FP, revealing that it retained 42% of its initial mass at a temperature of 600 °C. Additionally, the composite achieved a V-0 rating in the UL 94 test, confirming its excellent fire resistance. Notably, E 60-FP displayed impressive mechanical strength, with a tensile strength of 7.2 MPa and a tensile modulus of 1117.6 MPa. Its flexural strength and modulus were measured at 31.2 MPa and 2800.2 MPa, respectively. Furthermore, the composite E 60-FP exhibited remarkable electrical conductivity, measuring 6.1 × 10 ^–6 S cm ^−1 . These findings highlight the potential of DGEBA epoxy composites containing PANI and ATH as promising materials for applications requiring fire resistance and electrical conductivity properties.

Inducing roughness to achieve superhydrophobic surfaces through nanoparticlesʹ inclusion is a well-known concept; however, the consistency and secondary pollutants are challenges to be addressed. As a potential solution, we proposed a superhydrophobic nanofibrous membrane through the electrospinning of polyacrylonitrile and hydrophobic polydimethylsiloxane (PAN/H-PDMS) blended solution and post-heat treatment process. During carbonization, a drastic differential shrinkage between PAN and H-PDMS induces a hierarchically nanorough surface of the electrospun nanofiber. Thanks to the synergistic combination of micro-nano scale hierarchical roughness, a significant improvement in superhydrophobicity was observed with the water contact angle (WCA) of 163.48° and sliding angle (SA) of 4.2°. The proposed composite superhydrophobic nanofibrous membrane (CSN-M) exhibited excellent robustness against the tape peel, abrasion, and bending cycles by maintaining WCA higher than 158° and SA less than 6.5°. The outstanding self-healing feature recovered the WCA to 162.25° and lowered the SA to 5.0° after heat treatment at 60 °C. In addition, the CSN-M revealed a tensile modulus of 12.11 Mpa, a hydrostatic pressure of 39.18 cmH2O, and excellent breathability. The developed CSN-M is strong, with high permeability and outstanding mechano-chemical durability, making it a suitable choice for water/oil separation and self-cleaning applications.

Kapok fiber is emerging as a cheaper natural fiber having excellent thermal insulation properties. Recycled polyester/kapok blended needle punched nonwoven waddings are prepared where the effect of kapok fiber %, sheet areal density, and needle punch density on thermal resistance and air permeability is measured and analyzed with the help of MINITAB®18.1. Three percentages of kapok fiber (20, 40, 60%), four levels of fabric areal density (150, 300, 450, 600 g.m-2) and two levels of punch density (15, 20 punches.cm-2) were chosen. The statistical analysis revealed that kapok fiber % and areal density had a significant effect on both thermal resistance and air permeability of nonwovens. The thermal resistance was decreased significantly with the increase in kapok fiber %, especially at higher punch density. A significant interaction between kapok fiber % and areal density was observed for air permeability. It may be concluded that, in the selected range of input variables, recycled PET/kapok nonwovens with less % of kapok fibers and punch density display better thermal insulation performance, especially at higher areal density. The prepared nonwovens may find applications in winter coats and wadding layers for quilts, etc., and will also help to reduce the pollution from the environment.

Internal Combustion (IC) engines are prevalent in the process sector, and maintaining sufficient Air-Fuel Ratio (AFR) regulation in their fuel system is crucial for enhanced engine performance, fuel economy, and environmental safety. Faults in the AFR system's sensors cause the engine to shut down, hence, fault tolerance is essential. In order to avoid engine shutdown, this paper offers a novel Active Fault-Tolerant Control System (AFTCS) for air-fuel ratio control of an Internal Combustion (IC) engine in a process plant. In the Fault Detection and Isolation (FDI) unit, the proposed AFTCS uses a nonlinear regression-based observer model for analytical redundancy. The suggested system was simulated in the MATLAB / Simulink environment. The proposed system was tested at two different speeds (300 r/min and 600 r/min) and the results show that the system's response is within the acceptable bound without compromising the stability. The findings also demonstrate the higher fault tolerance capability for sensor defects of the AFR control system, particularly for the MAP sensor (at 300 r/min) in terms of reduced oscillatory response in comparison to the current literature. Compared to the linear regression-based and Genetic Algorithm (GA) based model, the nonlinear regression-based model results in a more accurate estimation of the faulty sensors. The proposed model is also efficient in terms of computation power and response time.

Nanoscale surface roughness has conventionally been induced by using complicated approaches; however, the homogeneity of superhydrophobic surface and hazardous pollutants continue to have existing challenges that require a solution. As a prospective solution, a novel bubbled-structured silica nanoparticle (SiO2) decorated electrospun polyurethane (PU) nanofibrous membrane (SiO2@PU-NFs) was prepared through a synchronized electrospinning and electrospraying process. The SiO2@PU-NFs nanofibrous membrane exhibited a nanoscale hierarchical surface roughness, attributed to excellent superhydrophobicity. The SiO2@PU-NFs membrane had an optimized fiber diameter of 394 ± 105 nm and was fabricated with a 25 kV applied voltage, 18% PU concentration, 20 cm spinning distance, and 6% SiO2 nanoparticles. The resulting membrane exhibited a water contact angle of 155.23°. Moreover, the developed membrane attributed excellent mechanical properties (14.22 MPa tensile modulus, 134.5% elongation, and 57.12 kPa hydrostatic pressure). The composite nanofibrous membrane also offered good breathability characteristics (with an air permeability of 70.63 mm/s and a water vapor permeability of 4167 g/m2/day). In addition, the proposed composite nanofibrous membrane showed a significant water/oil separation efficiency of 99.98, 99.97, and 99.98% against the water/xylene, water/n-hexane, and water/toluene mixers. When exposed to severe mechanical stresses and chemicals, the composite nanofibrous membrane sustained its superhydrophobic quality (WCA greater than 155.23°) up to 50 abrasion, bending, and stretching cycles. Consequently, this composite structure could be a good alternative for various functional applications.

Nanofiber-based facial masks have attracted the attention of modern cosmetic applications due to their controlled drug release, biocompatibility, and better efficiency. In this work, Azadirachta indica extract (AI) incorporated electrospun polyvinyl alcohol (PVA) nanofiber membrane was prepared to obtain a sustainable and hydrophilic facial mask. The electrospun AI incorporated PVA nanofiber membranes were characterized by scanning electron microscope, Ultraviolet-visible spectroscopy (UV-Vis) drug release, water absorption analysis, 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging, and antibacterial activity (qualitative and quantitative) at different PVA and AI concentrations. The optimized nanofiber of 376 ± 75 nm diameter was obtained at 8 wt/wt% PVA concentration and 100% AI extract. The AI nanoparticles of size range 50~250 nm in the extract were examined through a zeta sizer. The water absorption rate of ~660% and 17.24° water contact angle shows good hydrophilic nature and water absorbency of the nanofiber membrane. The UV-Vis also analyzed fast drug release of >70% in 5 min. The prepared membrane also exhibits 99.9% antibacterial activity against Staphylococcus aureus and has 79% antioxidant activity. Moreover, the membrane also had good mechanical properties (tensile strength 1.67 N, elongation 48%) and breathability (air permeability 15.24 mm/s). AI-incorporated nanofiber membrane can effectively be used for facial mask application.

Sweat is a natural body excretion produced by skin glands, and the body cools itself by releasing salty sweat. Wetness in the underarms and feet for long durations causes itchiness and an unpleasant smell. Skin-friendly reusable sweat pads could be used to absorb sweat. Transportation of moisture and functionality is the current challenge that many researchers are working on. This study aims to develop a functional and breathable sweat pad with antimicrobial and quick drying performance. Three layered functional sweat pads (FSP) are prepared in which the inner layer is made of an optimized needle-punched coolmax/polypropylene nonwoven blend. This layer is then dipped in antimicrobial ZnO solution (2, 4, and 6 wt.%), and super absorbent polymer (SAP) is embedded, and this is called a functional nonwoven (FNW1) sheet. Electrospun nanofiber-based nanomembranes of polyamide-6 are optimized for bead-free fibers. They are used as a middle layer to enhance the pad’s functionality, and the third layer is again made of needle-punched optimized coolmax/polypropylene nonwoven sheets. A simple nonwoven-based sweat pad (SSP) is also prepared for comparison purposes. Nonwoven sheets are optimized based on better comfort properties, including air/water vapor permeability and moisture management (MMT). Nonwoven webs having a higher proportion of coolmax show better air permeability and moisture transfer from the inner to the outer layer. Antimicrobial activity of the functional nonwoven layer showed 8 mm of bacterial growth, but SSP and FSP showed only 6 mm of growth against Staphylococcus aureus. FSP showed superior comfort and antibacterial properties. This study could be a footstone toward highly functional sweat pads with remarkable comfort properties.

Synthetic antibiotics have captured the market in recent years, but the side effects of these products are life-threatening. In recent times, researchers have focused their research on natural-based products such as natural herbal oils, which are eco-friendly, biocompatible, biodegradable, and antibacterial. In this study, polyethylene oxide (PEO) and aqueous ginger extract (GE) were electrospun to produce novel antibacterial nanomembrane sheets as a function of PEO and GE concentrations. A GE average particle size of 91.16 nm was achieved with an extensive filtration process, inferring their incorporation in the PEO nanofibres. The presence of the GE was confirmed by Fourier transform infrared spectroscopy (FTIR) through peaks of phenol and aromatic groups. The viscoelastic properties of PEO/GE solutions were analysed in terms of PEO and GE concentrations. Increasing PEO and GE concentrations increased the solution’s viscosity. The dynamic viscosity of 3% was not changed with increasing shear rate, indicating Newtonian fluid behaviour. The dynamic viscosity of 4 and 5 wt% PEO/GE solutions containing 10% GE increased exponentially compared to 3 wt%. In addition, the shear thinning behaviour was observed over a frequency range of 0.05 to 100 rad/s. Scanning Electron Microscopy (SEM) analysis also specified an increase in the nanofibre’s diameter with increasing PEO concentration, while SEM images displayed smooth morphology with beadless nanofibres at different PEO/GE concentrations. In addition, PEO/GE nanomembranes inhibited the growth of Staphylococcus aureus, as presented by qualitative antibacterial results. The extent of PEO/GE nanomembrane’s antibacterial activity was further investigated by the agar dilution method, which inhibited the 98.79% Staphylococcus aureus population at 30% GE concentration.

Textile-supported nanocomposite as a scaffold has been extensively used in the medical field, mainly to give support to weak or harmed tissues. However, there are some challenges in fabricating the nanofiber/textile composite, i.e., suitable porous structure with defined pore size, less skin contact area, biocompatibility, and availability of degradable materials. Herein, polyamide-6 (PA) nanofibers were synthesized using needleless electrospinning with the toothed wheel as a spinneret. The electrospinning process was optimized using different process and solution parameters. In the next phase, optimized PA nanofiber membranes of optimum fiber diameter with uniform distribution and thickness were used in making nanofiber membrane–textile composite. Different textile fabrics (woven, non-woven, knitted) were developed. The optimized nanofiber membranes were combined with non-woven, woven, and knitted fabrics to make fabric-supported nanocomposite. The nanofiber/fabric composites were compared with available market woven and knitted meshes for mechanical properties, morphology, structure, and chemical interaction analysis. It was found that the tear strength of the nanofiber/woven composite was three times higher than market woven mesh, and the nanofiber/knitted composite was 2.5 times higher than market knitted mesh. The developed composite structures with woven and knitted fabric exhibited improved bursting strength (613.1 and 751.1 Kpa), tensile strength (195.76 and 227.85 N), and puncture resistance (68.76 and 57.47 N), respectively, than market available meshes. All these properties showed that PA nanofibers/textile structures could be utilized as a composite with multifunctional properties.

Safety and critical applications employ fault-tolerant control systems (FTCS) to increase reliability and availability in the event of a failure of critical components. Process facilities may employ these technologies to cut down on production losses caused by equipment failures that occur on an irregular or unscheduled basis. Air–fuel ratio (AFR) adjustment in the fuel system of internal combustion engines (ICE) is crucial for enhancing engine efficiency, saving fuel energy, and safeguarding the environment. This paper proposes a novel hybrid fault-tolerant control system (HFTCS) for controlling the AFR in ICEs that combines the features of both an active fault-tolerant control system (AFTCS) and a passive fault-tolerant control system (PFTCS). The fault detection and isolation (FDI) unit is designed using fuzzy logic (FL) as part of an AFTCS to give estimated sensor values to the engine controller when the sensor becomes faulty. Super-twisting sliding mode control (ST-SMC) is implemented as part of a PFTCS to maintain AFR by adjusting the throttle actuator in the fuel supply line under faulty conditions. Lyapunov stability analysis is also performed to make sure that the system remains stable in both normal and faulty conditions. According to the results in the Matlab/Simulink environment, the suggested system stays robust and stable during sensor faults. In faulty situations, it also maintains the AFR at 14.6 without any degradation, and a comparison with previous studies is carried out. The study shows that the suggested approach is an innovative and highly dependable solution for AFR control in ICEs, preventing engine shutdown and output loss for higher profitability.

In this article, three distinct strategies for designing an Active Fault-Tolerant Control System (AFTCS) for Air-Fuel Ratio (AFR) control of an Internal Combustion (IC) engine in a process plant to avoid engine shutdown, are presented. The proposed AFTCS employs a Genetic Algorithm (GA), Particle Swarm Optimization (PSO), and a Nonlinear Regression (NLR)-based observer model in the Fault Detection and Isolation (FDI) unit for analytical redundancy. A comparison between these three proposed techniques is carried out to determine the least expensive and most accurate approach. The results show that the nonlinear regression produces highly accurate results by consuming very low computational power, and its response time is also very low as compared to GA and PSO. The results obtained show that NLR requires 99.6% and 93.1% less computational time for throttle and MAP estimation, respectively, by reducing the estimation error to as low as 0.01. The simulation of the proposed system is carried out in the MATLAB/Simulink environment. The results prove the superior fault tolerance performance for sensor faults of the AFR control system, especially for the Manifold Absolute Pressure (MAP) sensor in terms of less oscillatory response as compared to that reported in existing literature.

Fault-tolerant control systems (FTCS) are used in safety and critical applications to improve reliability and availability for sustained operation in fault situations. These systems may be used in process facilities to reduce significant production losses caused by irregular and unplanned equipment tripping. Internal combustion (IC) engines are widely used in the process sector, and efficient air–fuel ratio (AFR) regulation in the fuel system of these engines is critical for increasing engine efficiency, conserving fuel energy, and protecting the environment. In this paper, a hybrid fault-tolerant control system has been proposed, being a combination of two parts which are known as an active fault-tolerant control system and a passive fault-tolerant control system. The active part has been designed by using the genetic algorithm-based fault detection and isolation unit. This genetic algorithm provides estimated values to an engine control unit in case of a fault in any sensor. The passive system is designed by using the higher-order sliding mode control with an extra fuel actuator in the fuel supply line. The performance of the system was tested experimentally in MATLAB/Simulink environment. Based on the simulation results, the designed system can sustain the AFR despite sensor failures. A new method of managing the AFR of an IC engine has been demonstrated in this study, and it is highly capable, robust, reliable, and highly effective. A comparison with the existing works found in the literature also proves its superior performance. By inserting the fault in each sensor, it was clearly observed that proposed HFTCS was much better than the existing model as it was more fault-tolerant due to its ability to work in both online and offline modes. It also provided an exact value of 14.6 of AFR without any degradation.

Faults frequently occur in the sensors and actuators of process machines to cause shutdown and process interruption, thereby creating costly production loss. centrifugal compressors (CCs) are the most used equipment in process industries such as oil and gas, petrochemicals, and fertilizers. A compressor control system called an anti-surge control (ASC) system based on many critical sensors and actuators is used for the safe operation of CCs. In this paper, an advanced active fault-tolerant control system (AFTCS) has been proposed for sensor and actuator faults of the anti-surge control system of a centrifugal compressor. The AFTCS has been built with a dedicated fault detection and isolation (FDI) unit to detect and isolate the faulty part as well as replace the faulty value with the virtual redundant value from the observer model running in parallel with the other healthy sensors. The analytical redundancy is developed from the mathematical modeling of the sensors to provide estimated values to the controller in case the actual sensor fails. Dual hardware redundancy has been proposed for the anti-surge valve (ASV). The simulation results of the proposed Fault-tolerant control (FTC) for the ASC system in the experimentally validated CC HYSYS model reveal that the system continued to operate in the event of faults in the sensors and actuators maintaining system stability. The proposed FTC for the ASC system is novel in the literature and significant for the process industries to design a highly reliable compressor control system that would continue operation despite faults in the sensors and actuators, hence preventing costly production loss.

Stainless-steel fibre hybrid spun yarns are becoming increasingly popular due to their wide range of applications. In this aspect, the cost-effective and scalable processing of such yarns is highly important. Stainless-steel staple fibres are relatively heavier and weaker compared to conventional textile fibres. As a result, the staple spinning processing of these fibres showing higher tensile strength and productivity both at the same time is quite challenging. In this manuscript, we explored a number of spinning techniques to find the optimised method of producing low-twist and high-strength stainless-steel fibre hybrid spun yarns offering the advantage of both quality and productivity. Conventional ring spinning, folding and twisting, and advanced ring spinning techniques (ARSTs) such as pneumatic compact ring spinning and pneumatic compact SIRO spinning were employed in this study. Additionally, the plain and SIRO yarns were produced in two forms using the compact spinning method, one with pneumatic suction active (compact plain, compact SIRO) and other with pneumatic suction inactive (noncompact plain, noncompact SIRO). The tensile properties of yarns were tested and analysed. The results reveal that the tensile properties of conventional ring-spun and plied yarns can be enhanced to some extent by increasing the twist coefficient (TC) and the number of yarn plies, respectively. In contrast, by finding optimised spinning parameters, a substantially higher tensile strength (up to 16%) of yarns, produced at ARSTs, was observed even at the minimum level of TC used in experiments. The findings of the study are extremely valuable in terms of scaling up the production of high-quality metallic fibre hybrid spun yarns at a higher productivity level.