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The purpose of equal channel angular pressing (ECAP) is producing ultra-fine grain materials. In practical applications, it is important to understand and predict effect of different process parameters on deformed parts. One of the most important process parameters is friction coefficient. Behavior evaluation of different lubricants in the ECAP process is the aim of this research.

The present study concerns the experimental measurements of the effective strain by means of gridded parts for three different lubricants, graphite, molybdenum disulfide and zinc stearate, to evaluate friction coefficient in ECAP process. Mesh size was 2 × 2 mm² and embedded in parts made of AL2024; process was done in ambient temperature, and parts were in annealed situation. After the process, strain measured by optical and analytical methods for evaluation of lubricants’ behavior with different friction coefficients.

This study shows that zinc stearate has better effects rather than other lubricants in ECAP process and ECAPed parts.

The fatal challenge for researchers and industrial applications of ECAP process is lubrication. This research is a guide for scientists and engineers (in the future applications) to reduce and control bad frictional effects, produce better parts (more strain homogenous parts), prevent die failures and decrease press tonnage in ECAP process.

The objective of this paper is twofold as follows: first, it explores the relationship between economic growth and the environment in the context of the environmental Kuznets curve (EKC) in Iran, as a semi-industrialized and largest developing economy in the Middle East. Second, it investigates the effectiveness of government spending on environmental protection.

The paper uses the ecological footprint data and an ARDL model to gauge the income and government spending effects on environmental improvement. This method avoids the problems associated with using the regression including a squared income.

The results find no evidence for a turning point in the income–pollution relationship and no significant impact of government spending on reducing footprint. We conjecture that the structure of the economy and the weak institutional quality may explain the results.

This includes limited time series data on institutional quality indices and their small variations over time.

Creating an environmental fund using the oil windfall and applying environmental tax/subsidies policies will help address increasing environmental challenges in energy-rich developing countries. Education and public awareness about environmental problems and their impacts on the standard of living are also nonexpensive but effective ways to increase citizen's engagement towards improving environment.

The EKC may take different forms in various countries depending on their economic structure and institution qualities.

The paper uses the ARDL method rather than a commonly used regression with a squared income to estimate the EKC. It also uses ecological footprint as a measure of environmental damage. Exploring government effectiveness in managing public good is also novel in the empirical literature.

Internet of things (IoT) is essential in technical, social and economic domains, but there are many challenges that researchers are continuously trying to solve. Traditional resource allocation methods in IoT focused on the optimal resource selection process, but the energy consumption for allocating resources is not considered sufficiently. This paper aims to propose a resource allocation technique aiming at energy and delay reduction in resource allocation. Because of the non-deterministic polynomial-time hard nature of the resource allocation issue and the forest optimization algorithm’s success in complex problems, the authors used this algorithm to allocate resources in IoT.

For the vast majority of IoT applications, energy-efficient communications, sustainable energy supply and reduction of latency have been major goals in resource allocation, making operating systems and applications more efficient. One of the most critical challenges in this field is efficient resource allocation. This paper has provided a new technique to solve the mentioned problem using the forest optimization algorithm. To simulate and analyze the proposed technique, the MATLAB software environment has been used. The results obtained from implementing the proposed method have been compared to the particle swarm optimization (PSO), genetic algorithm (GA) and distance-based algorithm.

Simulation results show that the proper performance of the proposed technique. The proposed method, in terms of “energy” and “delay,” is better than other ones (GA, PSO and distance-based algorithm).

The paper presents a useful method for improving resource allocation methods. The proposed method has higher efficiency compared to the previous methods. The MATLAB-based simulation results have indicated that energy consumption and delay have been improved compared to other algorithms, which causes the high application of this method in practical projects. In the future, the focus will be on resource failure and reducing the service level agreement violation rate concerning the number of resources.

The proposed technique can solve the mentioned problem in the IoT with the best resource utilization, low delay and reduced energy consumption. The proposed forest optimization-based algorithm is a promising technique to help enterprises participate in IoT initiatives and develop their business.

The purpose of this paper is to report on the development of magnetorheological (MR) fluids, having high on-state shear stress/viscosity, low off-state shear stress/viscosity, good redispersibility and stable suspension of carbonyl iron particles, using tetramethyl ammonium hydroxide (TAH) and oleic acid.

MR fluids for use in brakes are synthesized using different weight percentages of silicone oil, TAH, oleic acid and iron particles. The effects of TAH and oleic acid are studied. Shear stress is measured as a function of magnetic field on a magneto-rheometer. The images of MR particles settling with time are presented. The test set-up used to evaluate the performance of the MR fluids synthesized for brake application is detailed. Finally, a significant improvement in the MR performance of brakes is reported.

The MR fluid having 0.25 Wt.% oleic acid showed low off-state viscosity/shear stress and high on-state viscosity/shear stress. A higher weight percentage of TAH in the MR fluid further reduced the low off-shear stress and increased the high on-state shear stress with better stability.

Improvement of MR brake performance by adding surfactants like TAH and oleic acid has been the subject matter of several studies in the past, but these studies used a fixed percentage of surfactants in MR fluids. In the present work, the optimum percentage of TAH and oleic acid for an improved braking performance is determined by varying their content in the MR fluid, which has not been reported in any other work thus far.

The metaverse has garnered increasing attention from researchers and practitioners, yet numerous firms remain hesitant to invest in it due to ongoing debates about its potential financial benefits. Therefore, it is crucial to analyze how the implementation of metaverse initiatives affects firms’ stock market value – an area that remains underexplored in the existing literature. Additionally, there is a significant lack of research on the contingency factors that shape the stock market reaction, leaving a noticeable gap in managerial guidance on the timing and benefits of investments in the metaverse. To narrow these gaps, we examine whether and when the implementation of metaverse initiatives enhances firms’ stock market value.

Based on 73 metaverse implementation announcements disclosed by Chinese listed firms during January 2021–August 2023, we employ an event study approach to test the hypotheses.

We find that metaverse implementation announcements elicit a positive stock market reaction. Moreover, the stock market reaction is stronger for technology-focused announcements and smaller firms, or when public attention to the metaverse is higher. Nevertheless, firms’ growth prospects do not significantly alter the stock market reaction.

This study extends the nascent literature on the metaverse by applying signaling theory to offer novel insights into the signaling effect of metaverse implementation announcements on stock market value and the boundary conditions under which the effectiveness of the signal varies. Besides, it provides managers with important implications regarding how to tailor the investment and information disclosure strategies of the metaverse to more effectively enhance firms’ stock market value.

This study investigated the production of free and encapsulated nanoemulsions using Cordia myxa fruit peel (CMFP) extract and vitamin D3.

The CMFP extract was obtained using an ultrasonic technique, and its characteristics such as total phenolic content (TPC), antioxidant activity, cytotoxicity and gas chromatography-mass spectrometry (GC/MS) analysis were assessed. CMFP was encapsulated in vitamin D3 oil droplets of nanoemulsion prepared by ultra-homogenization using calcium alginate polymer. The nanoemulsions were evaluated for 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity, antimicrobial activity, morphology, Fourier transform infrared (FTIR) analysis and release rate in a simulated gastrointestinal model.

The GC/MS results revealed that pyrocatechol, cholestanoids and propionaldehyde were the predominant compounds in the extract. The highest cytotoxicity effect of CMFP was observed at concentrations of 6.25 and 12.5 ppm of the extract. Encapsulated nanoemulsions exhibited the highest antimicrobial activity against Escherichia coli (ATCC 35218). The antioxidant activity of the free and encapsulated nanoemulsions ranged from 25.81 to 36.08 mg/100g and 49.25–55.7 mg/100g, respectively. Free nanoemulsions showed a higher release rate in the simulated gastric model compared to encapsulated ones. The FTIR spectrum allowed for the identification of functional groups responsible for antioxidant and antibacterial properties, indicating that these properties of the nanoemulsions were maintained.

This study demonstrates the successful co-encapsulation of CMFP extract and vitamin D3 in nanoemulsions, which significantly enhanced the stability, bioavailability and functional properties of both compounds. Encapsulated nanoemulsions exhibited higher antioxidant and antimicrobial activities compared to their free counterparts, with controlled release in simulated gastrointestinal conditions. These findings confirm that nanoemulsion-based encapsulation is an effective strategy to protect and enhance the bioactivity of plant extracts and vitamins, supporting their potential use in functional food products and therapeutic application.

The healthcare ecosystem continues to evolve with new technological developments with the support of its stakeholders. The technology-driven and patient-centric Healthcare 5.0 (H5.0) ecosystem is undergoing a transformation promising enormous benefits. However, the need to identify and understand the inherent challenges and barriers faced in the journey of H5.0 implementation and the relevant countermeasures for accelerated implementation has become critical.

The current research paper has utilised the Delphi approach for the collection of information and applied a well-proven quality function deployment (QFD) methodology for analysis.

The house of quality (HOQ) tool from the QFD has highlighted the critical H5.0 challenges which contribute to, approximately, 60% of the total weight. The identified top five process descriptors from the developed HOQ also contribute, approximately 60% among overall countermeasures. A useful H5.0 implementation progress (HIP) index has been recommended for tracking the progress made in the H5.0 implementation journey.

This research is among the first that has provided the application of the HOQ approach in the QFD methodology in the domain of H5.0. It has provided useful insights to the stakeholders. Furthermore, the development of a simple and practical HIP index is another useful value addition.