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Dissimilar materials found applications in the structural fields to withstand the different types of loads and provide multi-facet properties to the final structure. Aluminum alloy materials are mostly used in aerospace and marine industries to provide better strength and safeguard the material from severe environmental conditions. The purpose of this study is to develop new material with superior strength to challenge the severe environmental conditions.

In the present investigation, friction stir welding (FSW) dissimilar joints were prepared from AA6061 and AA5083 aluminum alloys, and the weld nugget (WN) was reinforced with hard reinforcement particles such as La₂O₃ and CeO₂. The tribological and mechanical properties of the prepared materials were tested to analyze the suitability of material in the aerospace and marine environmental conditions.

The results showed that the AA6061–AA5083/La₂O₃ material exhibited better mechanical and tribological characteristics. The FSW dissimilar AA6061–AA5083/La₂O₃ material exhibited lower wear rate of 7.37 × 10⁻³ mm3/m and minimum friction coefficient of 0.31 compared to all other materials owing to the reinforcing effect of La₂O₃ particles and the fine grains formed by FSW process at WN region. Further, FSW dissimilar AA6061–AA5083/La₂O₃ material displayed a maximum tensile strength and hardness of 378 MPa and 118 HV, respectively, among all the other materials tested.

This work is original and novel in the field of materials science engineering focusing on tribological characteristics of friction stir welded dissimilar aluminum alloys by the reinforcing effect of hard particles such as La₂O₃ and CeO₂.

In wireless sensor networks, improving the network lifetime is considered as the prime objective that needs to be significantly addressed during data aggregation. Among the traditional data aggregation techniques, cluster-based dominating set algorithms are identified as more effective in aggregating data through cluster heads. But, the existing cluster-based dominating set algorithms suffer from a major drawback of energy deficiency when a large number of communicating nodes need to collaborate for transferring the aggregated data. Further, due to this reason, the energy of each communicating node is gradually decreased and the network lifetime is also decreased. To increase the lifetime of the network, the proposed algorithm uses two sets: Dominating set and hit set.

The proposed algorithm uses two sets: Dominating set and hit set. The dominating set constructs an unequal clustering, and the hit set minimizes the number of communicating nodes by selecting the optimized cluster head for transferring the aggregated data to the base station. The simulation results also infer that the proposed optimized unequal clustering algorithm (OUCA) is greater in improving the network lifetime to a maximum amount of 22% than the existing cluster head selection approach considered for examination.

In this paper, lifetime of the network is prolonged by constructing an unequal cluster using the dominating set and electing an optimized cluster head using hit set. The dominator set chooses the dominator based on the remaining energy and its node degree of each node. The optimized cluster head is chosen by the hit set to minimize the number of communicating nodes in the network. The proposed algorithm effectively constructs the clusters with a minimum number of communicating nodes using the dominating and hit set. The simulation result confirms that the proposed algorithm prolonging the lifetime of the network efficiently when compared with the existing algorithms.

The proposed algorithm effectively constructs the clusters with a minimum number of communicating nodes using the dominating and hit sets. The simulation result confirms that the proposed algorithm is prolonging the lifetime of the network efficiently when compared with the existing algorithms.

Aluminum alloys are applicable in marine and aero fields. Alloys AA5083 and AA6061 are aluminum alloys with different chemical and physical properties. Combination of two dissimilar materials could result in enhanced strength. Generally, dissimilar aluminum alloy joint is made by friction stir welding (FSW) to achieve improved physical properties compared with the parent alloys. The purpose of this research is to develop a new FSW dissimilar material with enhanced properties using AA5083 and AA6061 alloys.

In this research, FSW joint was made for butt joint configuration using AA5083 and AA6061 aluminum alloys. Cylindrical pin with threaded profile was used to perform the joint. The tool tilting angle was maintained as constant, and the tool rotational speed and the welding speed were varied. Wear performance and mechanical strength of the joint were analyzed.

The results revealed that the increase of tool rotational speed led to poor wear performance, whereas increase of welding speed showed a better wear performance. Further, the prepared joint was analyzed for different wear parameters such as sliding velocity and applied load. The results displayed that the increase of sliding velocity exhibited low wear rate and the increase of load showed high wear rate.

This work is original and deals with the wear performance of AA5083–AA6061 joint at different tool rotational and welding speeds.

This paper aims to investigate the effect of Cu content and T6 heat treatment on the mechanical properties and the tribological performance of SiCp/Al-Si-Cu-Ni-Mg hybrid composites at an elevated temperature.

The stir casting method was used to synthesize SiCp/Al-12Si-xCu-1Ni-1Mg (x = 2, 3, 3.5, 4, 4.5, 5 Wt.%) composites containing 20 vol% SiC. The hardness and tensile strength of the aluminum matrix composites (AMCs) at room temperature and elevated temperature were studied, and the wear mechanism was investigated using scanning electron microscopic and energy dispersive spectroscopy.

Results indicate that the hardness and tensile strength of the AMCs are affected significantly by T6 heat treatment and Cu content. The high-temperature friction and wear mechanism of AMCs is the composite wear mechanism of oxidation wear, adhesion wear, abrasive wear, peeling wear, high-temperature softening and partial melting. Among them, adhesion wear, high-temperature matrix softening and local melting are the main wear mechanisms.

The influence mechanism of Cu content on the hardness, tensile strength and high temperature resistance of AMCs was explained by microstructure. And the results further help to explore the application of AMCs in high temperature.

For Internet celebrities, self-disclosure (SD) is a crucial step in building relationships with their followers who perceive this communication as para-social interaction (PSI), which facilitates socialization among followers. Normative commitment (NC) is critical for creating bonds among community members that are strengthened through socialization. However, research on the predictive relationships among SD, PSI and NC has been insufficient. This paper aims to investigate the effects of two facets of Internet celebrity SDs (i.e. private life and opinion) and two facets of PSI (i.e. companionship and following) on NC. The mediating role of PSI on the effects of SD on NC was also analyzed.

People who follow at least one Internet celebrity on a social networking site were recruited to participate in this study, and 494 valid questionnaires were collected for examination. The collected data were analyzed using structural equation modeling (SEM).

The results revealed that both private-life and opinion SDs have positive effects on companionship and following PSI, which consequently influence NC. A mediation test revealed that companionship and following PSI mediate the effects of private-life and opinion SD on NC. This study's findings also revealed that NC is influenced more by following PSI than it is by companionship PSI. Furthermore, opinion SD was determined to be the more influential factor in following PSI, whereas private-life SD was the more influential factor in companionship PSI.

This paper is useful for understanding the influence mechanism of the SD of Internet celebrities on PSI and NC.

Considers the focus group as an alternative to the traditional structured questionnaire. Their appeal, what they can and cannot achieve, and four key questions related to conducting focus groups are discussed. Focus groups are relevant to a broad spectrum of marketing issues related to the food industry, and it is concluded that their role will continue to dominate qualitative market research. Increasingly high standards will be demanded of moderators, perhaps leading to recognised qualifications for the holding of focus groups.

Decoupling of pressures ranging from regulatory compliance and stakeholders expectations to business competitiveness and sustainability, companies need to align their environmental strategies with a broader consideration of these influences. This paper aims at developing a dynamic alignment model to enhance the environmental performance that considers the influential pressures based on a multi-criteria decision-making process.

Authors have proposed a dynamic model for the alignment of the environmental performance based on a hybrid multi-criteria decision-making approach combining the analytic hierarchy process (AHP) and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS). This model considers contemporary strategic dynamism of the environmental performance and provides a methodology to assist companies prioritizing the environmental aspects based on the influential pressures and deciding on the enhancement pathways.

The proposed model based on a hybrid multi-criteria decision-making process allows prioritizing the environmental aspects considering the allocated weights to the alignment-triggered pressures and draw the way to develop different pathways to improve the alignment.

The proposed dynamic alignment model presents an instrument for the continuous alignment of the environmental performance and an effective management of changes and contributes to minimize gaps and divergences.

In this paper, the environmental performance has been approached through the contemporary strategic dynamism with the deployment of the multi-criteria decision-making techniques to yield an alignment framework for the environmental decision that combines the internal and external approaches for an effective and sustainable improvement of the environmental performance.

Green walls (GWs), comprising living walls and green facades, have been touted as environmentally friendly products in architectural design. GWs can be viable in every aspect of sustainability; they provide residents of buildings with a wide range of economic, social and environmental benefits. Despite this, the adoption rate of GW is still in its infancy stage, and the existing literature concerning the hindrances inhibiting GW adoption is very limited. To address these gaps, the aim of this paper is to identify and prioritize the hindrances to GW adoption in Hong Kong.

After identifying 17 hindrances through an in-depth review of literature, the fuzzy Delphi method (FDM) is employed to refine the hindrances based on the local context with the help of 21 qualified experts in the field. Subsequently, Fuzzy Parsimonious Analytic Hierarchy Process (FPAHP) is exploited as a recently developed technique to prioritize the identified hindrances.

Results reveal that the most significant hindrances to the adoption of GW are maintenance cost, high installation cost, difficulties in maintenance, sophisticated implementation and inducement to fire. Findings call for scholars to address ways to improve GW installation practices and methods in order to eradicate the hindrances and provide lessons for policymakers, assisting them in facilitating the larger-scale adoption of GW.

Considering the dearth of studies on hindrances to the adoption of GWs, this paper provides a comprehensive outlook of the issue, providing knowledge that can be used as a building block for future scholars within the field. It also provides valuable insights for stakeholders within the construction industry about the hindrances to the adoption of GWs which could direct their efforts toward better implementation of it.

Urbanization is characterized mainly by changes in land use and conversion of natural areas into built environments, as well as by a series of impacts, such as loss of biodiversity, which interfere with the proper functioning of ecological networks.

Thus, the authors apply a bibliometric analysis using the term “Urban Trees” in the “Web of Science” database, between 2009 and 2019, as a keyword to include all urban green structures and identify the main aspects of urban ecological relationships. They found 8,367 published articles.

This review identified the main countries and research institutions that operate in urban afforestation. In general, developing countries seek to understand the environmental benefits that urban afforestation can provide, demonstrating the importance of maintaining existing green areas in urban centers to promote the balance of the ecosystem. It depends directly on the flow of ecosystem services provided by green infrastructures in the city, contributing significantly to carbon sequestration, retention of particulate matter, mitigation of heat islands and reduction of surface runoff, directly favoring the health and well-being of the population. The authors conclude that the actions currently implemented in urban afforestation, especially to increase the richness and abundance of species, will be decisive for the future of urban centers and the construction of more sustainable and egalitarian cities.

This work sought to develop a bibliographic research based on information obtained by bibliometric analysis that has the ability to identify trends and volumes of scientific production in a given area of knowledge.

Data-driven marketing is replacing conventional marketing strategies. The modern marketing strategy is based on insights derived from customer behavior information gathered from their facial expressions and neuro-signals. This study explores the potential for face recognition and neuro-marketing in modern-day marketing.

The study conducts an in-depth examination of the extant literature on neuro-marketing and facial recognition marketing. The articles for review are downloaded from the Scopus database, and PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) is then used to screen and choose the relevant papers. The systematic literature review method is applied to conduct the study.

An extensive review of the literature reveals that the domains of neuro-marketing and face recognition marketing remain understudied. The authors’ review of selected papers delivers five neuro-marketing and facial recognition marketing themes that are essential to modern marketing concepts.

Neuro-marketing and facial recognition marketing are artificial intelligence (AI)-enabled marketing techniques that assist in gaining cognitive insights into human behavior. The findings would be of use to managers in designing marketing strategies to enhance their marketing approach and boost conversion rates.

The uniqueness of this study lies in that it provides an updated review on neuro-marketing and face recognition marketing.