Search Results (49)

Although consumption is a key engine of economic growth, it is also one of the main drivers of environmental degradation. In this context, a deeper understanding of consumers’ perceptions and behavior regarding sustainable products is essential for promoting a more sustainable future, with behavioral change being crucial to achieving it. This research study explores consumer behavior regarding sustainable egg consumption, a sector where production is frequently associated with environmental and ethical concerns such as animal welfare and intensive resource use. Based on a sample of 197 valid responses from Portuguese egg consumers collected through an online survey distributed between 27 February and 17 March, of the year 2025, and applying the Theory of Planned Behavior (TPB) framework through a structural equation modeling (SEM) approach, this study finds that consumers’ intention to consume sustainable eggs is influenced by their attitudes and subjective norms. Furthermore, actual consumption behavior is driven by both the intention to consume sustainable eggs and perceived behavioral control. By providing an in-depth analysis of consumer behavior related to sustainable egg consumption, this study contributes to the advancement of the scientific literature on the subject. It also aims to support policymakers and other stakeholders in designing and implementing more effective strategies to promote environmentally responsible consumption practices. Full article

To improve the traction performance of mobile mechanisms on soft ground, such as paddy fields, tidal flats, and swamps, a mallard (Anas platyrhynchos) foot was adopted as a bionic prototype to explore the influence and contribution of the plantar morphology of the toes and webbing on the anti-subsidence function during its locomotion on wet and soft substrates and to apply this to the bionic design of high-traction wheel grousers. A handheld three-dimensional laser scanner was used to scan the main locomotion postures of a mallard foot during ground contact, and the Geomagic Studio software was utilized to repair the scanned model. As a result, the main three-dimensional geometric models of a mallard foot during the process of touching the ground were obtained. The plantar morphology of a mallard foot was divided into three typical parts: the plantar irregular edge curve, the lateral webbing surface, and the medial webbing surface. The main morphological feature curves/surfaces were extracted through computer-aided design software for the fitting and construction of a mathematical model to obtain the fitting equations of the three typical parts, and the mathematical model construction of the plantar irregular morphology of the mallard foot was completed. In order to verify the sand-fixing and flow-limiting characteristics of this morphological feature, based on the discrete element method (DEM), the numerical simulation of the interaction between the plantar surface of the mallard foot and sand particles was carried out. The simulation results show that during the process of the mallard foot penetration into the loose medium, the lateral and medial webbing surfaces cause the particles under the foot to mainly move downward, effectively preventing the particles from spreading around and significantly enhancing the solidification effect of the particles under the sole. Based on the principle and technology of engineering bionics, the plantar morphology and movement attitude characteristics of the mallard were extracted, and the characteristics of concave middle and edge bulge were applied to the wheel grouser design of paddy field wheels. Two types of bionic wheel grousers with different curved surfaces were designed and compared with the traditional wheel grousers of the paddy field wheel. Through pressure-bearing simulation and experiments, the resistance of different wheel grousers during the process of penetrating into sand particles was compared, and the macro–micro behaviors of particle disturbance during the pressure-bearing process were analyzed. The results show that a bionic wheel grouser with unique curved surfaces can well encapsulate sand particles at the bottom of the wheel grouser, and it also has a greater penetration resistance, which plays a crucial role in improving the traction performance of the paddy field wheel and reducing the disturbance to the surrounding sand particles. This paper realizes the transformation from the biological model to the mathematical model of the plantar morphology of the mallard foot and applies it to the bionic design of the wheel grousers of the paddy field wheels, providing a new solution for improving the traction performance of mobile mechanisms on soft ground. Full article

This paper identifies and examines the latest research on renewable energy in Poland, reviewing articles published between 2021 and 2023 indexed in the Scopus database. It analyzes 124 papers, categorizing them into 11 thematic areas which include (1) energy production, (2) energy consumption, (3) energy policy, (4) sustainable development activities, (5) technology and engineering, (6) energy storage, (7) powering vehicles, (8) awareness and attitude regarding energy, (9) finances and investments, (10) emission, and (11) other. The main objective was to analyze the state of the current research on renewables in Poland. The results highlight significant progress in renewable energy capacity, particularly in wind and solar power, driven by national policies, EU funding, and growing public support. The analysis also reveals persistent challenges related to technology, infrastructure, and policy. The authors critically evaluate the research’s relevance to Poland’s energy sector and globally. They also refer to issue of non-renewable energy sources, which, despite the development of the RES sector, still play a dominant role in the Polish energy economy. Due to this, the article not only describes the state of knowledge, but also formulates conclusions on the real needs and opportunities for the further development of energy in Poland. Full article

In this work, a vertical landing mechanism of a reusable launch vehicle (RLV) is investigated using a flexible–rigid coupled dynamics model. The presented model takes into account the four-legged landing mechanism and the main body cabin. Flexibilities of the main components in the vertical landing mechanism are considered. The hydro-pneumatic spring force and thrust aftereffect caused by the sequential deactivation of the engine are introduced separately. Several simulation cases are selected to analyze the loads acting on the landing mechanism and the dynamics behavior of the whole RLV system. Simulation results show that considering flexibility in the landing mechanism is critical for dynamics analysis under various initial conditions. The adopted RLV design is capable of achieving stable landings under specified initial velocity and attitude conditions, demonstrating its feasibility for engineering applications. Moreover, the hydro-pneumatic spring plays a crucial role in absorbing the impact of the initial landing leg, ensuring a smoother landing experience and minimizing potential damage to the vehicle. Full article

Digital transformation (DT) has become an important engine for the development of the digital economy and an important means of reshaping corporate culture, business processes, management models, and so on. Different social communities at different levels have different needs and understandings of digital transformation. Therefore, this paper proposes to explore the communication themes of digital transformation on social media. This study’s main objective is to uncover underlying thematic structures and core ideas from large amounts of textual data in different social media communities to better understand the significance of the communication themes. This paper also aims to reveal the characteristics of diffusion patterns of DT themes by opinion-themed mining. This study uses text mining and social network analysis methods to mine DT themes, theme structure, and the statistical characteristics of hot words across various online communities. The main findings of this study are as follows. The Huawei forum discusses the technological drivers of the digital economy from a micro level. Sohu News explores business operation strategies at a macro level. The Zhihu forum discusses the elements of digital development at the micro level. Moreover, the hot words’ degree centrality and betweenness centrality across various online communities exhibited a power law distribution. In conclusion, this research paper studies and analyzes DT themes of different social media platforms to discover the opinions and attitudes of various social groups in the digital transformation era and deeply interprets social trends and public opinions in order to provide valuable decision-making theoretical support for managers, enterprises, and governments. Full article

This paper addresses the issue of insufficient accuracy and efficiency in existing methods for the alignment of marine propulsion systems with single stern tube bearing, caused by uncertainties in the actual parameters of propulsion systems and the scarcity of data, and a new alignment method based on fine-tuning a pre-trained model is proposed. First, a characterization method for the attitude of the main engine is proposed, taking into account the specific alignment requirements of marine propulsion systems with single stern tube bearing. Next, a pre-trained model is constructed based on large-scale samples from the design propulsion system and the fine-tuning of the pre-trained model is performed using small samples from the actual propulsion system’s alignment process to obtain the target model, which guides the practical alignment. Finally, the effectiveness and superiority of the proposed method are validated by applying actual measured data and by applying finite element simulations; in eight alignments, all verification parameter errors are much smaller than the maximum allowable error. The results show that the proposed method significantly improves the accuracy and efficiency of alignment of this type of propulsion system and provides a technical approach to the small-sample modeling problem in the alignment of propulsion systems. Full article

The construction industry is a key driver of economic development in a developing country like Sri Lanka. However, many construction projects still face serious safety challenge areas such as poor attitude, bad conduct, negligence, out-of-date legislation, a lack of qualified safety officers and financial constraints. This study aims to determine which safety challenges are the key ones in the Sri Lankan construction industry and how these challenges are classified and related to each other. The significance of this research is that it identifies the most important safety challenge areas and addresses them, which helps to overcome other safety challenge areas that rely on them. To achieve this aim, survey questionnaires were developed, and a survey was conducted among key project stakeholders, including safety officers, engineers, managers, quantity surveyors and human resources personnel, to collect information on significant safety factors that can help in improving safety. Forty-three safety challenge elements were identified and assessed through factor analysis. The ten most significant safety challenge elements were extracted and categorised into two main categories: (i) economy-related and (ii) human-resource-related challenges. The results of this survey provide a very good foundation for project managers or safety managers to identify certain criteria when selecting construction staff and making project plans. Full article

With the growing emphasis on sustainability, awareness of the environmental impacts and negative potential inherent in current business systems has increased. The circular economy (CE) represents an innovative approach that transforms the traditional linear economy into a restorative system, focussing on extending the life cycle of materials through continuous circulation. The Circular B project aims to develop an international framework that considers multiple facets of the CE, including material and asset management and the use of components in the built environment throughout the entire life cycle of the value chain. The primary objective of the CE is to eliminate waste and pollution (e.g., carbon reduction) and strengthen the resilience of the value chain. However, the current implementation of circular strategies has not yet been found to be effective, with several challenges that cause adverse impacts. This study focuses on investigating and analyzing these challenges, particularly in the cultural and societal domains, using both qualitative and quantitative approaches. The scope of the questionnaire was to identify (1) awareness and understanding, (2) cultural attitude, (3) barriers to adoption, (4) incentives and motivations, (5) participation and engagement, and (6) education and training. A questionnaire was distributed to 270 respondents, with anonymous responses collected. The survey included eight questions specifically designed to address cultural and societal challenges. The survey was conducted with participants from various sectors, including academia, local authorities, industry professionals, consultants, and others collected from all over the world, ensuring diverse perspectives. The main weaknesses found based on this survey are related to (1) budget constraints due to high costs of reintegrating in the loop of materials or components due to the complexity of circular processes, (2) applicability on the market remains still limited, (3) the importance of planning and design in the initial phases, (4) the importance of establishing a comprehensive network to enhance collaboration among stakeholders, and (5) inadequate policies. The insights gained from this study will help stakeholders, such as constructors, maintainers, engineers, designers, and consultants, across various organizations in the value chain to develop practical solutions to mitigate these challenges and improve the overall business system. Full article

This paper provides an overview of the social reasons that lead women to consider egg cryopreservation, as well as the attitudes and knowledge of women towards this procedure. Methods: For the creation of this article, a literature review was carried out both in the existing medical literature and in search engines. The key points are as follows: (1) The main reasons women choose to delay childbearing are the lack of a suitable male partner, education and career advancement, and financial instability. Women feel societal and family pressure to have children, even though they may not feel ready. (2) Women’s attitudes towards egg cryopreservation vary. While some are open to the idea, many are opposed to it, especially when it is used for non-medical reasons. There are concerns about the success rates, health risks, and ethical implications of the procedure. (3) The legal and regulatory framework around egg cryopreservation differs across countries. Some countries allow it only for medical reasons, while others have more permissive policies. The issue of who should bear the financial cost of the procedure is also debated. (4) There is a need to better educate women, as well as healthcare providers, about fertility decline and the options available for preserving fertility, including egg cryopreservation. Full article

In recent years, quadcopter-type unmanned aerial vehicles have been preferred in many engineering applications. Because of its nonlinear dynamic model that makes it hard to create optimal control, quadcopter control is one of the main focuses of control engineering and has been studied by many researchers. A quadcopter has six degrees of freedom movement capability and multi-input multi-output structure in its dynamic model. The full nonlinear model of the quadcopter is derived using the results of the experimental studies in the literature. In this study, the control of the quadcopter is realized using the symbolic limited optimal discrete controller synthesis (S-DCS) method. The attitude, altitude, and horizontal movement control of the quadcopter are carried out. To validate the success of the SDCS controller, the control of the quadcopter is realized with fractional order proportional-integral-derivative (FOPID) controllers. The parameters of the FOPID controllers are calculated using Fire Hawk Optimizer, Flying Fox Optimization Algorithm, and Puma Optimizer, which are recently developed meta-heuristic (MH) algorithms. The performance of the S-DCS controller is compared with the performance of the optimal FOPID controllers. In the path planning part of this study, the optimal path planning performances of the SDCS method and the MH algorithms are tested and compared. The optimal solution of the traveling salesman problem (TSP) for a single quadcopter and min-max TSP with multiple depots for multi quadcopters are obtained. The methods and the cases that optimize the dynamic behavior and the path planning of the quadcopter are investigated and determined. Full article

With the rapid development of marine engineering in recent years, offshore operations have become increasingly common, making wave compensation platforms crucial for safe operations at sea. This paper presents a pendulum-type wave compensation platform specifically designed for wave compensation applications. The main components of this wave compensation platform include a chassis, support base, hydraulic cylinders, telescopic rods, upper platform, three sets of balancing mechanisms, three sets of tilt angle sensors, and a control system. Firstly, to thoroughly understand the compensatory motion of the pendulum-type three-degree-of-freedom wave compensation platform, kinematic analysis of the entire system was conducted, and the motion inverse solution curves of the mechanism were obtained through simulation using motion simulation software. Secondly, to enhance the compensatory response performance of the platform, a fuzzy PID control algorithm was employed to control the system and achieve attitude control of the platform. Finally, through control system simulation, compared to PID control, fuzzy PID reduces system response delay and successfully meets the expected technical requirements and application needs. Full article

The accurate evaluation of aerodynamic characteristics is a prerequisite and foundation for the design of high-performance aerodynamic shapes, navigation guidance, and strength of projectiles. The nonlinearity of aerodynamic calculations for a projectile is high, and the modeling and simulation are difficult, especially under the high-angle of attack flight conditions. Small variations in flight conditions, and structural parameters, etc., may cause large deviations in aerodynamic responses. Taking a small cylindrical projectile as an example, and to realize its attitude control, it is necessary to conduct aerodynamic characteristics analysis on it and analyze the main influencing factors of its aerodynamic characteristics parameters. In this paper, the finite volume method is used to solve the three-dimensional unsteady N-S equation, combined with the SST k-ω turbulence model, the overlapping grid technology, and the forced pitching vibration method, and the aerodynamic characteristics analysis model of the projectile is established, which realizes the accurate simulation of the surrounding flow field, aerodynamic coefficients, and dynamic derivative of the projectile under different flight conditions. On this basis, the Sobol global sensitivity analysis method based on the augmented radial basis function surrogate model of aerodynamics characteristics and Latin hypercube sampling is used to efficiently analyze and obtain the main influence parameters of cylindrical projectile aerodynamic characteristics. This paper provides a basic theory and fast algorithm for subsequent engineering system design, which has important theoretical and engineering value. Full article

To address environmental challenges, the Architecture, Engineering, Construction, and Operations (AECO) industry, which is known for its high resource consumption and waste production, needs to switch to a circular economy (CE). This approach focuses on reducing, recycling, and reusing materials to narrow, slow, and close material loops. However, one of the main problems which the AECO industry is still facing is the lack of common, standardized, and automated procedures to consider the recyclability and presence of hazardous materials. To address this problem, this study focuses on extending the recyclability rate from the material to building scale, considering the presence of hazardous materials based on the European Waste Catalogue (EWC), hence defining a new KPI. It adopts Building Information Modelling (BIM) and Industry Foundation Classes (IFCs) and integrates them with bespoke programming in Python to develop a standardized and automated procedure that complies with Italian regulations. The new KPI will help clients and designers to rate the overall recyclability of a building and to choose the best combination of materials and components. The procedure includes data acquisition, transmission, and data/model integration, resulting in practical and trackable measures that could be globally scalable. Scenario analyses are also developed to consider the impact of maintenance attitude on waste production. Full article

The aim of this article is to present solutions related to wind energy in EU countries as an alternative to fossil fuels. This article is based on secondary information and statistical data regarding the development of wind power engineering in EU countries for the years 2016–2022. The main purpose of this paper is to analyze of the relations between the development of wind energy in European Union countries and GPD (gross domestic product) per capita and selected factors. The following hypotheses were formulated: H1—There is a statistically significant correlation between GDP per capita and the use of wind energy in European Union countries. H2—There is a relationship between the length of the coastline and the use of wind energy in European Union countries. H3—There is a statistically significant correlation between the attitude to uncertainty of the inhabitants of a given country and the use of wind energy in said country. The presented research results support all these hypotheses. The results of the research regarding H2 are as follows: in the case of northern European countries (Ireland and Finland) and the Iberian Peninsula (Spain and Portugal), the development of wind power engineering in the study period was faster than could be inferred from the length of the coastline in these countries. Regarding hypothesis H1, it was concluded on the basis of the analysis that the involvement of countries in the development of wind power engineering is correlated with their wealth. The novelty of this paper emerges from its innovative approach to analyzing wind power engineering, its incorporation of cultural factors, its quantitative assessment of correlations, and its actionable policy recommendations. These elements collectively contribute to a comprehensive and impactful study that advances our understanding of wind energy adoption in the European Union. Full article

This article analyses the media discourse about Islamophobia in Spain. Specifically, an overview of all the appearances of the term in four Spanish newspapers (ABC, El Mundo, El País, and La Vanguardia) is provided with the aim of finding out when the term was first used and became standard language. The study also demonstrates the links with the public interest and identifies the ideological and terminological attitudes in the discourse of each newspaper. The corpus includes 1475 news articles since the first reference (in 1987) to the term Islamophobia and May 2022, which were quantitatively examined in two steps. While the first was manual and served to document the historical background, the second allowed us to monitor the media content by means of Sketch Engine. Furthermore, the searches for the term “islamofobia” in Google Trends from Spain were also reviewed. The main findings show that both terrorist attacks in Western countries and the controversies surrounding freedom of speech are key to the emergence and normalisation of the concept, particularly since 2015. However, the interest of each newspaper differs, with El País covering the topic most frequently. This left-wing newspaper offers some notable variations in terminology as well. While the three right-wing newspapers consistently relate Islamophobia to threat, the vocabulary used in El País underpins the victimisation of the Arab-Islamic population. According to the Sketch Engine analysis, the usual terms that occur in combination with Islamophobia are racism, terrorism, violence, hate, anti-semitism, and xenophobia. Finally, Google Trends data confirmed the peak in public interest in the Barcelona and Cambrils attacks (17A). Full article