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The purpose of this study is to model the global dynamic hysteresis properties with an improved Jiles–Atherton (J-A) model through a unified set of parameters.

First, the waveform scaling parameters β, λ_k and λ_c are used to improve the calculation accuracy of hysteresis loops at low magnetic flux density. Second, the Riemann–Liouville (R-L) type fractional derivatives technique is applied to modified static inverse J-A model to compute the dynamic magnetic field considering the skin effect in wideband frequency magnetization conditions.

The proposed model is identified and verified by modeling the hysteresis loops whose maximum magnetic flux densities vary from 0.3 to 1.4 T up to 800 Hz using B30P105 electrical steel. Compared with the conventional J-A model, the global simulation ability of the proposed dynamic model is much improved.

Accurate modeling of the hysteresis properties of electrical steels is essential for analyzing the loss behavior of electrical equipment in finite element analysis (FEA). Nevertheless, the existing inverse Jiles–Atherton (J-A) model can only guarantee the simulation accuracy with higher magnetic flux densities, which cannot guarantee the analysis requirements of considering both low magnetic flux density and high magnetic flux density in FEA. This paper modifies the dynamic J-A model by introducing waveform scaling parameters and the R-L fractional derivative to improve the hysteresis loops’ simulation accuracy from low to high magnetic flux densities with the same set of parameters in a wide frequency range.

This paper aims to prepare high corrosion-resistant chromium-free zinc-aluminum (Zn–Al) coatings reinforced with multi-walled carbon nanotubes (MWCNTs) and nano-ZnO particle composites.

The morphology, composition and corrosion resistance of the coatings were analyzed by electrochemical tests, water contact angle tests, immersion tests, scanning electron microscopy/energy dispersive spectrometer and X-ray diffraction.

The composite coating with 0.3% MWCNTs and 0.5% nano-ZnO particles demonstrated both high shielding performance and cathodic protection performance, which was attributed to the porosity filling of MWCNTs and nano-ZnO particles together with the electrical connection of MWCNTs between the zinc and aluminum powders.

This work laid an experimental foundation for the preparation and corrosion mechanism of high corrosion-resistant chromium-free Zn–Al coating reinforced with MWCNTs and nano-ZnO particles.

This paper aims to report the effect of titanium oxide (TiO₂) particles on the specific wear rate (SWR) of alkaline treated bamboo and flax fiber-reinforced composites (FRCs) under dry sliding condition by using a robust statistical method.

In this research, the epoxy/bamboo and epoxy/flax composites filled with 0–8 Wt.% TiO₂ particles have been fabricated using simple hand layup techniques, and wear testing of the composite was done in accordance with the ASTM G99-05 standard. The Taguchi design of experiments (DOE) was used to conduct a statistical analysis of experimental wear results. An analysis of variance (ANOVA) was conducted to identify significant control factors affecting SWR under dry sliding conditions. Taguchi prediction model is also developed to verify the correlation between the test parameters and performance output.

The research study reveals that TiO₂ filler particles in the epoxy/bamboo and epoxy/flax composite will improve the tribological properties of the developed composites. Statistical analysis of SWR concludes that normal load is the most influencing factor, followed by sliding distance, Wt.% TiO2 filler and sliding velocity. ANOVA concludes that normal load has the maximum effect of 31.92% and 35.77% and Wt.% of TiO2 filler has the effect of 17.33% and 16.98%, respectively, on the SWR of bamboo and flax FRCs. A fairly good agreement between the Taguchi predictive model and experimental results is obtained.

This research paper attempts to include both TiO₂ filler and bamboo/flax fibers to develop a novel hybrid composite material. TiO₂ micro and nanoparticles are promising filler materials, it helps to enhance the mechanical and tribological properties of the epoxy composites. Taguchi DOE and ANOVA used for statistical analysis serve as guidelines for academicians and practitioners on how to best optimize the control variable with particular reference to natural FRCs.

Despite advancements in construction digitalisation and alternative building technologies, cost overrun is still a challenge in the construction industry. The inflation rate is increasing, especially in developing countries, and is critical in cost overrun matters. It can deviate construction built-up rate components. This may thwart improving construction-related Sustainable Development Goals (SDGs). Studies concerning the impact of the inflation rate on construction-related SDGs are scarce in developing countries, including Nigeria. The study investigated the impact of inflation on Nigeria’s construction projects and their outcome on SDGs and suggested possible ways to improve achievement of construction-related SDGs and their targets.

The researchers employed a qualitative research design. This is because of the study’s unexplored dimension. The researchers engaged 35 participants across major cities in Nigeria via semi-structured virtual and face-to-face interviews. The research utilised a thematic method for collated data and accomplished saturation.

Findings reveal that the impact of inflation on construction projects, if not checked, could hinder achieving construction-related SDGs in Nigeria. This is because of the past three years of hyperinflation that cut across major construction components. It shows that the upward inflation rate threatens achieving construction-related SDGs and proffered measures to mitigate inflation and, by extension, enhance achieving construction-related SDGs. This includes a downward review of the Monetary Policy Rate, control of exchange rate volatility and addressing insecurity to restore FDIs and FPIs confidence.

Besides suggesting possible solutions to mitigate hyperinflation on construction components to improve achieving construction-related SDGs, findings will stipulate government policymakers put measures in place through favourable fiscal and monetary policy implementation and encourage moving from a consumption to a production nation.

This study aims to enhance our understanding of sustainable water management in construction through a life-cycle embodied water assessment of a villa in the United Arab Emirates (UAE). It provides insights and recommendations for improving the water efficiency by identifying areas for potential embodied water saving and reduction in environmental impacts in the construction industry.

This study uses a life-cycle assessment (LCA) approach and focuses on a UAE villa as a case study. It analyses the embodied water consumption during construction (initial embodied water) and maintenance (recurrent embodied water) using an input–output-based hybrid analysis. Additionally, it compares the embodied water observations with the operational water usage and comprehensively evaluates the water consumption in the villa’s life-cycle.

The initial (28%) and recurrent embodied water (42%) represent significant proportions of a building’s life-cycle water demand. The structural elements, predominantly concrete and steel, contribute 40% of the initial embodied water consumption. This emphasises the importance of minimising the water usage in these materials. Similarly, internal finishes account for 47% of the recurrent embodied water. This emphasises the importance of evaluating the material service life.

These findings indicate the efficacy of using durable materials with low embodiment and water-efficient construction methods. Additionally, collaborative research between academia, industry, and the government is recommended in conjunction with advocating for policies promoting low embodied-water materials and transparency in the construction sector through embodied water footprint reporting.

Previous studies focused on the operational water and marginally addressed the initial embodied water. Meanwhile, this study highlights the significance of the initial and recurrent embodied water in the life-cycle water demand. It emphasises on the need for adaptable buildings with reduced embodied water and more durable materials to minimise the requirement for frequent material replacements.

Metal laser-powder-bed-fusion using laser-beam parts are particularly susceptible to contamination due to particles attached to the surface. This may compromise so-called technical cleanliness (e.g. in NASA RPTSTD-8070, ASTM G93, ISO 14952 or ISO 16232), which is important for many 3D-printed components, such as implants or liquid rocket engines. The purpose of the presented comparative study is to show how cleanliness is improved by design and different surface treatment methods.

Convex and concave test parts were designed, built and surface-treated by combinations of media blasting, electroless nickel plating and electrochemical polishing. After cleaning and analysing the technical cleanliness according to ASTM and ISO standards, effects on particle contamination, appearance, mass and dimensional accuracy are presented.

Contamination reduction factors are introduced for different particle sizes and surface treatment methods. Surface treatments were more effective for concave design features, however, the initial and resulting absolute particle contamination was higher. Results further indicate that there are trade-offs between cleanliness and other objectives in design. Design guidelines are introduced to solve conflicts in design when requirements for cleanliness exist.

This paper recommends designing parts and corresponding process chains for manufacturing simultaneously. Incorporating post-processing characteristics into the design phase is both feasible and essential. In the experimental study, electroless nickel plating in combination with prior glass bead blasting resulted in the lowest total remaining particle contamination. This process applied for cleanliness is a novelty, as well as a comparison between the different surface treatment methods.

This paper presents a new and well-structured framework that aims to assess the current environmental impact from a Greenhouse Gas (GHG) emissions perspective. This tool includes a new set of Lean Key Performance Indicators (KPIs), which translates the well-known logic of Overall Equipment Effectiveness in the field of GHG emissions, that can progressively detect industrial losses that cause GHG emissions and support decision-making for implementing improvements.

The new metrics are presented with reference to two different perspectives: (1) to highlight the deviation of the current value of emissions from the target; (2) to adopt a diagnostic orientation not only to provide an assessment of current performance but also to search for the main causes of inefficiencies and to direct improvement implementations.

The proposed framework was applied to a major company operating in the plywood production sector. It identified emission-related losses at each stage of the production process, providing an overall performance evaluation of 53.1%. The industrial application shows how the indicators work in practice, and the framework as a whole, to assess GHG emissions related to industrial losses and to proper address improvement actions.

This paper scrutinizes a new set of Lean KPIs to assess the industrial losses causing GHG emissions and identifies some significant drawbacks. Then it proposes a new structure of losses and KPIs that not only quantify efficiency but also allow to identify viable countermeasures.

The quantum of metal particle waste generation in manufacturing industries is posing a great concern for the environment. The iron forging industries generate a huge amount of grinding sludge (GS) waste, which is disposed into the earth. The accumulation of this waste in dump yards causes an increase in soil and air pollution levels.

In the current investigation, an effort was made to use this waste GS for the progress of aluminum-based composite. To maintain uniform distribution of reinforcing material, the friction stir processing technique was used.

The characterization based on the SEM image of the Al/GS composite revealed that uniform dispersal of reinforcement content can be attained in a single tool pass. Number of grains/inch was approximately 2,402. XRD of GS powder confirmed the presence of SiO₂, Fe₂O₃, Al₂O₃ and CaO phases. These phases proved GS to be a better reinforcement with aluminum alloy. Tensile strength and hardness were significantly improved in comparison to the aluminum alloy. Thermal expansion and corrosion weight loss were evaluated to observe the influence of GS addition.

The studies proved that the use of GS as reinforcement material can help in curbing the menace of soil pollution to a large extent.

This study aims to explore the possibilities for regional (intra and inter) trade between Central Asia and South Asia (CASA) by examining several frameworks that impact the economic integration of these regions.

The study uses five indices, specifically the export diversification index, export survival rates, export sophistication, revealed comparative advantage and intra-industry trade index in South and Central Asia, from 2005 to 2021.

The findings show a twofold increase in the potential trade value between the two regions compared to the actual level. The intra-regional trade in Central Asia accounts for less than 5% of trade with all countries, whereas the intra-regional trade in South Asia accounts for 1.5%, and the inter-regional trade accounts for between 0.2 and 4% of total trade to all destinations. The intensity of trade measurements shows that inter-regional trade flows are modest because they make up a relatively small percentage of the entire trade volume, which includes all destinations, ranging from 0.2 to 4 %.

These findings have a significant impact on the successful implementation of trading-related measures, initiatives and institutional mechanisms for encouraging improved trade between and within both regions.

Export diversification initiatives aim to provide favourable outcomes for all parties involved, focusing on expanding the range of goods and services exchanged. CASA countries with higher diversification have shown more favourable outcomes than those relying on a restricted range of products. The authors expect policies promoting a broader array of exports to boost market shares, while maintaining a narrow focus may hinder new export prospects. In addition, regional value chains and policy initiatives promoting trade and investment could lead to increased value additions to exports, technological transfers and job creation.

The study emphasises the significance of trade-related policies, programmes and institutional mechanisms in promoting trade between CASA. It emphasises the need for policies that support investment and trade, adopt new requirements of the Agreement on Trade Facilitation and promote diversity and latency.

Based on economic analysis, the study offers practical insights and strategies for businesses in the CASA regions. It also provides analytical tools for academics and decision makers, as well as policy and programme recommendations for government agencies, development partners, researchers and individuals interested in trade dynamics in these regions.