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Simultaneous optimization of multiple responses in machining processes is a challenging task to process engineers. Conflicting type response and cumbersome internal mathematical steps of optimization method itself make the task more difficult. Some discrete multi-response optimization methods namely WSN, GRA, VIKOR, MOORA and TOPSIS methods involve comparatively simpler implementation procedures. For simultaneous optimization of average depth of cut and average kerf taper in abrasive waterjet machining process, the five methods are employed. Different normalization techniques, data conversion methods and combination methods for responses are used. Optimum results are validated through confirmation test. Optimum results for different weight factor combinations are also checked. Performance of multi-response optimization methods is compared with the aid of Spearman’s rank correlation coefficient.

Medium carbon steel is one of the most abundantly used materials globally due to its availability, low cost, and wide range of properties. On the other hand, medium carbon steel has a significant disadvantage in terms of corrosion and wear resistance. In this research work the medium carbon steel substrate is electroplated with ternary alloy Zn–Ni–W to improve the hardness and resistance to corrosion in the steel substrate. Providing a Zn–Ni–W alloy sacrificial thin layers with a trace amount of W on the surface of a mild steel substrate improves its corrosion and wear resistance. The electrolyte composition is optimized in such a way that the coating is rich in Zn which makes it a sacrificial type coating. The coating is done in an acidic sulfate bath with current density and pH of 1 A/dm² and 5 respectively. The electrodeposition process is carried out at two different temperatures 55 °C and 70 °C with a deposition time of 30 min respectively. Surface morphology, chemical content, phase structure, and the thickness of these coatings are studied and compared using SEM, EDS, and XRD. Corrosion and wear behavior of Zn–Ni–W alloy coating has been done with the help of Electrochemical impedance spectroscopy (EIS). In conclusion, EIS results reveal notable characteristics for the Zn–Ni–W sample coated at 70 °C. The thin film exhibited a low corrosion rate and corrosion current, indicating a enhanced resistance against corrosion. Furthermore, the high polarization resistance value emphasizes the film's effectiveness in inhibiting corrosion processes. These findings collectively emphasize the favorable corrosion-resistant properties of the Zn–Ni–W coating deposited at 70 °C.

This study provides an innovative approach about chromized-doped layers by discovering the optimal proportion of Mg (1 wt.%, 2 wt.%, and 3 wt.%) used as doping elements in order to enhance diffusion and stabilize the formed chromium oxide during the diffusion process. Our main objective is to evaluate the effect of Mg doping on the microstructural and the electrochemical behavior of the doped layer, systematically evaluating the impact of simultaneous variation of NH₄Cl activator. The chromized-doped layers were analyzed by X-ray diffraction (XRD) and a scanning electron microscopy (SEM) equipped with EDX analysis. The doped layers were tested in 3.5% NaCl solution, and then were characterized by electron probe micro-analyzer (EPMA). The results revealed that doping contributed to the improvement of chromium diffusion for all the layers (≥ 96% Cr), stabilizing chromium oxide by forming a more stable oxide (MgCr₂O₄). However, Cr-Mg/1 wt.% showed the most homogenous crystalline structure and topography compared to the other layers, with the most insignificant defects. The Cr-Mg/1 wt.% presented an excellent corrosion resistance in the 3.5% NaCl solution, where its surface did not suffer any type of corrosion or damages. In addition, the balanced value of the activator (NH₄Cl) relative to the other doped layers may play a significant role. As a result, the Cr-Mg/1 wt.% (using 4 wt.% NH₄Cl) could be a robust and innovative surface, paving the way for new possibilities in the field of chromizing coatings.

Heavy metal contamination in surface water is a worldwide concern. Being the primary source of river pollution, the wastewater drains bring agricultural and domestic waste into the rivers. The present study was carried out to evaluate levels of heavy metals from wastewater drains of River Ghaggar in Punjab (India). The water samples were collected in five different seasons to carry out this work. The concentration of five metals (lead, cadmium, iron, aluminium, and nickel) was determined through Microwave Plasma-Atomic Emission Spectroscopy (MP-AES) technique. The data were interpreted through various environmental and human health risk assessments. The results of the current study revealed that lead, iron, and aluminium exceeded the permissible limit of the Central Pollution Control Board (India). Pollution indices such as the heavy metal pollution index (HPI), heavy metal evaluation index (HEI), water pollution index (WPI), and degree of contamination (C_d), suggested enormous heavy metal contamination in the study area. Human health risk assessment also revealed that people dwelling near these drains are highly prone to cancer disease and hazard quotients were observed above the threshold limit that poses high non-carcinogenic risks. Based on the current study, recommendations are made for water quality improvement in the wastewater drains of Punjab. These drains are further responsible for enhancing pollution in the main rivers in the State of Punjab and heavy metal pollution also poses several environmental and health risks. The compiled data during the present study provides a baseline model that can be helpful in resource management for government authorities of Punjab state.

It is not possible to directly measure the reaction forces and moments acting on the joints in the living things without damaging the integrity of the body. L5/S1 joint in the human body have a higher damage potential than other joints. In this study, it is aimed to develop a method that can calculate the net reaction forces and moments acting on the L5/S1 and upper extremity joints by using only kinematic measurement inputs, without the need for force measurement from the points where the feet contact the ground. For this purpose, 3D biomechanical model suitable for human anatomy was created. Kinematic analyzes were performed using the Denavit–Hartenberg (DH) method. Iterative Newton–Euler (NE) method was used for inverse dynamic calculations. The kinematic measurement inputs of joint movements were obtained by the subject in an experimental study involving the lifting task a certain load from the ground and lowering it to a high place. The model was verified by comparing the results obtained using the proposed method with each other and with the literature data.

The influence of annealing treatments at 600°C, 750°C, and 900°C on the alloy structure and memory properties was investigated in this study using a powder-core wire fusion-deposited Fe-14Mn-6Si-9Cr-5Ni alloy, accompanied by a preliminary analysis of the effects of annealing temperature. The results show that compared with the alloy annealed at 600°C, the alloy annealed at 750°C has less crossover of cooling martensite, resulting in improved ordering of stress-induced martensite during pre-deformation, and consequently, enhanced memory properties. At 900°C, ferrite almost completely decomposed, promoting martensitic growth through the crystal, which sharply decreased the memory properties, only slightly better than those of the unannealed alloy. It can be seen that annealing at the appropriate temperature can regulate the morphology and amount of cooling martensite in the additively manufactured Fe-Mn-Si-Cr-Ni alloy, thus improving the memory properties. However, excessively high annealing temperatures can cause excessive decomposition or even disappearance of δ-ferrite, which stabilizes the grain boundaries, thus adversely affecting the memory properties of the alloy.

A polymer processing method called rotational moulding is utilised to make hollow things without tension. Despite being the resin matrix of choice for rotational moulding, linear low-density polyethylene (LLDPE) performs only moderately in areas where sturdiness is required. In order to maintain the necessary strength, fibres might fill the gap. A variety of testing methods, including FTIR, particle size distribution, bulk density, MFI, DSC, and TGA, were used to support the requirement of processability for rotational moulding in the current study. Peanut shell powder (PSP) was combined with the LLDPE at amounts varying from 2 to 20%. The importance of both materials’ peaks can be seen in FTIR results, which suggested a range of 8% to 18% PSP in LLDPE. Particle size distribution and Bulk density measurement indicated that blends above 14% PSP are not recommended for rotational moulding. Based on MFI data, it was determined that PSP blends of 14% and above have values lower than 3 g/10min which is not suitable in terms of sufficient flow ability in rotational moulding. The inclusion of PSP was found to increase the blend’s crystallinity by 6.6% for 12% PSP blend. As per DSC and TGA data, adding peanut shell powder to LLDPE does not significantly alter the processing temperature range as compared to neat LLDPE, making rotational moulding appropriate for blends containing 8% to 12% PSP.

In the present time, cloud platforms are gaining more popularity for outsourcing features. So, many public or private organizations are fascinated towards cloud technology since it can handle enormous amounts of data. Cloud services also enable secure data exchanges among the registered and legitimate users. Depending on data sensitivity, cloud dependent data transfer suffers from security and privacy issues. This raises a big challenge for cloud dependent data sharing. Available solutions are having some limitations such as failure at single point, inconvenient and inefficient in terms of weak data model or revocation of user. In this research, we have suggested a quorum based scheme. In the suggested scheme, the quorum concept is assimilated with HM-ACS. For non-quorum and quorum approaches, experiments are performed. Thus, experimental analysis proved that the proposed schemes are performing much better in terms of key generation, memory required, encryption decryption and computation requirements. These schemes are also efficient and secured against all threats for data and user privacy.

The efficient management of a diverse truck fleet presents a significant challenge within the realm of logistics and transportation management. The primary objective revolves around optimizing fleet efficiency by assigning the most suitable truck type to each task, all while accommodating an array of constraints such as delivery time windows, capacity limits. In this study, we introduce a Mixed Integer Non Linear Programming (MINLP) model tailored for the optimization of heterogeneous truck fleets, facilitating the precise allocation of trucks to their respective roles. Employing the CPLEX as our decision-making tool, we conduct computational experiments that underscore the effectiveness of our MINLP model and CPLEX solver in enhancing the operational efficiency of heterogeneous truck fleets while adhering rigorously to various constraints and compare the solution with Genetic Algorithm. The findings convincingly demonstrate the potential of our proposed methodology to furnish logistics and transportation managers with invaluable insights, ultimately contributing to the sustainability and efficiency of modern logistics and transportation systems.

Super Duplex Stainless Steels (SDSS), in spite of their numerous commercial applications is considered to be extremely difficult to machine owing to its poor thermal conductivity, severe chemical affinity, and work hardening nature. Several studies have analysed the possibility of adopting conventional lubrication/cooling methods and coating techniques to address the machinability-related challenges of the alloy. However, limited studies have explored the use of multi-layered coatings to enhance the tool life properties while machining the alloy. Hence, this work intends to investigate the impact of using CVD TiCN-Al₂O₃ coated tools to analyse the significance of parameters like speed, feed rate, and depth of cut on the machinability aspects of SDSS 2507 in dry turning conditions. The experimentation analysis revealed that while speed, feed rate, and depth of cut had a significant impact on influencing the tool wear characteristics, surface roughness values were impacted by only feed rate values. Similarly, feed rate, depth of cut, and interaction effects between these factors were noted to have a considerable influence on the cutting forces. Meanwhile, the study also focuses on developing an analytical model to predict the cutting forces that consider the sticking-sliding effects by incorporating the chip groove area across the machining interface. The predicted cutting force values were observed to be in close agreement with the experimental results. The error values were noted to be below 15% in the majority of the cases, which confirms the significance of the predicted model.