Approximation of a system of nonlinear Carrier wave equations by approximating the Carrier terms with their integral sums

This paper is concerned with the approximation of a system of nonlinear Carrier wave equations (CEs) by approximating the Carrier terms with their integral sums. At first, under suitable conditions, the linear approximate method, the Galerkin method, and compactness arguments provide the unique existence of a weak solution (un,vn) of the problem (Pn), for each n ∈ N, for a system of nonlinear wave equations related to Maxwell fluid between two infinite coaxial circular cylinders. Next, we prove that {(un,vn)}n converges to the weak solution (u,v)of the problem for a system of CEs in a suitable function space. This proof is done by using the compactness lemma of Aubin-Lions and the method of continuity with a priori estimates. We end the paper with a remark related to open problems

Optimizing airway network efficiency with the A-star algorithm: a case study of Ho Chi Minh FIR

Airway network optimization is crucial for airspace planning, addressing high traffic density and alleviating pressure on Air Traffic Controllers. With the rapid growth of civil aviation, overloaded airways and congestion have become significant challenges. Vietnam’s air transport sector plays a vital role in economic and social development, enhancing connectivity across the Asia-Pacific region. Additionally, Vietnam has led the global recovery of domestic aviation post-COVID-19 and, as the world’s fifth fastest-growing aviation market, is expected to reach 150 million air transport passengers by 2035. This highlights Vietnam’s dynamic growth and strategic importance within global aviation. However, this rapid expansion has exposed vulnerabilities in Vietnam’s airways, particularly within the Ho Chi Minh Flight Information Region (HCM FIR), where congestion and overload are evident, especially during adverse weather. To address these challenges, this study proposes optimizing the airway network in 2D space using the A-star algorithm, tailored for the HCM FIR. This approach aims to reduce flight distances, improve operational efficiency, and ease ATC workloads, marking a critical step toward enhancing Vietnam’s airspace management system

Could e-commerce activities drive to climate change mitigation? Novel evidence from panel quantile regression model

This study aims at shedding light on how e-commerce contributes to climate change in European Union countries. To explore this relationship, we introduced a novel index designed to measure the evolution of climate change as the dependent variable, while considering e-commerce activities as the independent variable within 2011 to 2022 period. Our investigation of the correlation between these variables employed a panel quantile regression model. The outcomes revealed a statistically significant increasing trend for higher quantiles. This finding indicates that, as we traverse the climate change index from lower to higher percentiles, the impact of e-commerce becomes more conspicuous and is statistically significant. This underscores that the influence of e-commerce on climate change intensifies as we move towards the upper percentiles of the climate change index. To address how e-commerce affects climate change, it becomes imperative to introduce and enforce the concept of environmental responsibility in the management of e-commerce activities. This could involve adopting sustainable practices, optimizing packaging materials, and encouraging eco-friendly delivery methods. Policymakers and businesses alike should consider these findings in their efforts to strike an equilibrium between the convenience of e-commerce and the need to curb its environmental impact

Collaborative actions to support SMEs\u27 sustainability in times of crisis

The paper provides a detailed analysis of SMEs’ interest in collaborative action for sustainability as a way of responding to the challenges posed by recent crises. This study attempts to bridge the research gap on how managers of small and medium-sized enterprises manage business sustainability, providing complex insights into the application of collaborative practices for sustainability and the collaborative advantages that can support the competitiveness of these enterprises in the marketplace. The research design is quantitative and targeted 672 SMEs in Romania. A moderated moderation analysis is also carried out, and the model tests the relationship between the age of the analysed SMEs and the impact felt after recent crises, a relationship moderated by sustainable cooperation, and a moderator moderated by possible changes felt from the application of collaborative practices. Finally, this regression function is statistically significant and was shown to be a significant moderated moderation. The research results showed the major impact of recent crises on the activity of SMEs, indicating that the interest of these companies in collaborative actions and the level of results expected from collaboration for sustainability decreases the greater the impact of crises on their business

Comparative efficiency testing of a composite hydraulic cylinder

The paper points to the increasing use of composite materials in hydraulic components. This entails many benefits, such as weight reduction which is particularly important in aviation. However, new problems arise with the use of new materials. With regard to a hydraulic actuator whose cylinder is made of a composite material, one of the issues is ensuring adequate efficiency, comparable to that of a steel cylinder. The efficiency of a hydraulic actuator is related to friction processes in the structural nodes and to leaks in the cylinder. This paper presents the original results of volumetric, hydraulic-mechanical and total efficiency tests of three designs differing in the material used as a liner of a cylinder. The materials considered as liner were CFRP composite, polyurethane F180. In addition, a steel liner was considered as a reference. Variations in actuator efficiency depending on the liner used were indicated

Smart tourism economics: introducing a technology-driven competitive advantages framework

Recently, in the Hospitality 5.0 era, the Smart Tourism industry has experienced disruptions due to the widespread integration of cutting-edge technologies (Artificial Intelligence, Internet of Things, Robots, Big Data, and others) enabling the overall tourist experience enhancement. This study aims to identify the main clusters of technologies adopted and to highlight the competitive advantages resulting from their implementation in Smart Tourism. A meta-analysis was conducted on a final WoS sample of 60 papers published between 2015 and 2023. Four synoptic tables showcase the technologies, the processes they facilitate, the competitive advantages, and the smart destinations where they have been implemented. The originality of this research consists of the 70 competitive advantages identified across the industry, leveraged in designing the CECoR map (Customer Experience, Costs, Revenues) and the CAdSTT framework (Competitive Advantage-driven Smart Tourism Technologies). Guidelines for supporting managers in planning and initiating projects aiming at integrating technology to increase organisational value were proposed

Residential satisfaction indicator: Latin American evidence

Latin American construction companies, particularly in Ecuador, operate in a highly competitive environment. In this context, achieving customer satisfaction is a primary objective for the success of real estate projects. This research aims to develop a comprehensive residential satisfaction index that includes sustainability dimensions, based on global satisfaction indices and structural equation modeling. This study will enable residential builders to assess their performance from the customer’s perspective and make strategic decisions aimed at improving quality, which, in turn, will lead to greater customer satisfaction in future projects. The findings of this research will provide valuable input for decision-making in the real estate sector, with a focus on the Latin American context

Utilization of recycled carbide as adsorbent for adsorption of dyes and COD from textile waste

This study assessed the potential of carbide waste (CW), a by-product of the welding industry, as a cost-effective adsorbent for removing dyes and COD from textile wastewater. CW was prepared through drying, filtering, and shaping into 2 mm-thick tablets (3 mm diameter), followed by heating at 150 °C for 120 minutes. Characterization using FTIR and SEM-EDX confirmed functional groups like hydroxyl and carbonyl and significant surface morphological changes. Batch experiments achieved maximum color and COD removal efficiencies of 94.48% and 96.73%, respectively, at 75 g adsorbent dosage and 150 min contact time. Freundlich isotherm (R² = 0.9918 for color) indicated heterogeneous adsorption, and kinetic studies fit a pseudo-second-order model. The process was exothermic, spontaneous, and governed by physical adsorption. Regeneration trials showed COD removal efficiency remained 90% after four cycles. These findings establish CW as an efficient, sustainable adsorbent with promising environmental and industrial applications for textile wastewater treatment

Diagnosis, management, and treatment of a heritage-built environment in South Chile

In Chile, photography arrived at the end of the 19th century together with the establishment of settlements of migrants from central Europe to southern Chile. The aims of this study are: (i) contextualise functional states of existing buildings in a specific sector of the historic Valdivia city centre; (ii) determine the state of conservation of the 42 cases under study; (iii) conduct qualitative and quantitative analyses of the main pathologies presented in the sample; (iv) perform an analysis focused on the urban context according to façade alignment, façade visibility index, and ratio of height versus street width; and (v) comparatively analyse the results achieved. This research reflects the importance of developing innovative procedures and mitigation strategies focused on preventive maintenance actions and future control systems that can maximise the resilience of a specific local context (Los Ríos region) and its surroundings. This study revealed that the number of pathologies detected was directly proportional to the state of conservation of the cases, classified by the functional service life model. Properties in Condition C were mainly affected by pathologies of a structural nature, which indicates that their functionality is not guaranteed, and a deeper inspection is needed for conservation and preservation actions. First published online 12 December 202

Improving obsessive-compulsive buying through brand attachment and hedonic value: customer-based brand value

This study aims to explore how hedonic value influences obsessive-compulsive buying behavior by examining the mediating roles of brand attachment and customer-based brand value. The research addresses inconsistencies in previous studies on the influence of hedonic market value on obsessive-compulsive buying by integrating brand attachment and customer-based brand value as key factors. The literature review reveals a gap in understanding the mediating role of these variables in the relationship between hedonic value and compulsive buying. Six hypotheses were developed and tested using PLS-SEM within a sample of 246 customers in Central Java, Indonesia. The results highlight that customer-based brand value significantly mediates the impact of hedonic value on brand attachment, which in turn enhances obsessive-compulsive buying. Additionally, the study finds that brand attachment directly contributes to the increase in compulsive buying behavior. The findings suggest that a positive customer experience, influenced by strong brand identity, is crucial in fostering brand attachment and subsequently driving obsessive-compulsive purchasing. This research provides a comprehensive understanding of how hedonic and brand-related factors interact to influence consumer behavior