Search Results (1,955)

With the advent of digitization, digital twin technology is gradually becoming one of the core technologies of the Industry 4.0 era, highlighting the increasing importance of digital twin project management. Despite its potential, DT projects face significant risks during implementation, stemming from technical, managerial, and operational complexities. To address these challenges, this study proposes an improved failure mode and effect analysis (FMEA) framework by integrating double hierarchy hesitant fuzzy linguistic term sets (DHHFLTSs) and the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS). This framework converts qualitative assessments into quantitative metrics and calculates weights using a hybrid approach, enabling more precise risk prioritisation. Application of the model to an automotive manufacturing company’s DT project identified key risks, particularly in the iteration and upgrade phase, emphasising the importance of cross-departmental collaboration and robust digital infrastructure. The proposed model provides a systematic framework for enterprises to assess and mitigate risks, ensuring the successful deployment of DT projects. Full article

Cross-flow turbines are widely used in microhydropower systems because of their cost-effectiveness, environmental sustainability, adaptability, and robust design. However, their relatively lower efficiency than other turbine types limit their application in large-scale projects. Previous studies have identified poor flow profiles as a significant factor contributing to inefficiency, with the number of blades playing a critical role in the flow behavior, efficiency, and structural stability. This study employed numerical simulations to analyze how varying the number of blades affects the internal flow characteristics and performance of the turbine at, and off, its best operating points. Configurations with 16, 20, 24, 28, 32, 36, 40, and 44 blades were investigated under constant low-head conditions, fully open valve settings, and varying runner speeds. Simulations were performed using ANSYS CFX, incorporating steady-state conditions, a two-phase flow model with a movable free surface, and a shear stress turbulence model. The results indicate that the 28-blade configuration achieved a maximum hydraulic efficiency of 83%, outperforming the preset 24-blade setup by 6%. Flow profiles were examined using pressure and velocity gradients to identify regions of adverse pressure. Due to the impulse nature of the turbine, the flow profile is more sensitive to changes in the flow speed than to pressure. The flow trajectory showed stability in the first stage but exhibited discrepancies in the second stage, which were attributed to turbulence, recirculation, and shaft flow impingement. The observed performance improvements were linked to reduced hydraulic losses due to flow separation and friction, emphasizing the significance of the number of blades and the regions of optimal efficiency under low-head conditions. Full article

As railway infrastructure projects become increasingly complex, the potential of Building Information Modeling (BIM) technology to enhance project efficiency and management has garnered significant attention. This paper analyzes the quantitative and qualitative benefits of BIM in the design and construction stages of railway development projects through case studies and compares its effectiveness in these two phases. The results indicate that BIM primarily benefits the design stage by reducing design errors and optimizing processes to save costs and time, averaging cost savings of USD 41,000 and a reduction of 49 days in project duration. In the construction stage, the impact of BIM is even more pronounced, reflected in reduced rework, dynamic resource management, and shortened project timelines, leading to savings of USD 710,795 and a reduction of 89 to 104.5 days in project duration. The 3D modeling and real-time information-sharing capabilities of BIM significantly enhance cross-departmental collaboration efficiency and information transparency, minimizing rework caused by communication issues and greatly optimizing project management and execution. This study shows that BIM can lay the groundwork for construction during the design phase and further improve project management efficiency during the construction phase. Full article

The accurate measurement of orchard canopy volume serves as a crucial foundation for wind regulation and dosage adjustments in precision orchard management. However, existing methods for measuring canopy volume fail to satisfy the high precision and real-time requirements necessary for accurate variable-rate applications in fruit orchards. To address these challenges, this study develops a canopy volume measurement model for orchard spraying using LiDAR point cloud data. In the domain of point cloud feature extraction, an improved Alpha Shape algorithm is proposed for extracting point cloud contours. This method improves the validity judgment for contour line segments, effectively reducing contour length errors on each 3D point cloud projection plane. Additionally, improvements to the mesh integral volume method incorporate the effects of canopy gaps in height difference calculations, significantly enhancing the accuracy of canopy volume estimation. For feature selection, a random forest-based recursive feature elimination method with cross-validation was employed to filter 10 features. Ultimately, five key features were retained for model training: the number of point clouds, the 2D point cloud contour along the X- and Z-projection directions, the 2D width in the Y-projection direction, and the 2D length in the Z-projection direction. During model construction, the study optimized the hyperparameters of partial least squares regression (PLSR), backpropagation (BP) neural networks, and gradient boosting decision trees (GBDT) to build canopy volume measurement models tailored to the dataset. Experimental results indicate that the PLSR model outperformed other approaches, achieving optimal performance with three principal components. The resulting canopy volume measurement model achieved an R² of 0.9742, an RMSE of 0.1879, and an MAE of 0.1161. These results demonstrate that the PLSR model exhibits strong generalization ability, minimal prediction bias, and low average prediction error, offering a valuable reference for precision control of canopy spraying in orchards. Full article

CO₂ sequestration is considered one of the main pillars in achieving the ongoing decarbonization efforts. A myriad of CO₂ sequestration projects targeted sandstone reservoirs since carbonate reservoirs appeared to be unpropitious due to their geological complexity and unfavorable mineralogy and properties. This study investigates CO₂ sequestration potential in a carbonate saline aquifer while considering various geological complexities by capitalizing on numerical simulation. A synthetic anticline reservoir model examined the optimum well location and landing zone for CO₂ sequestration. Additionally, the model evaluated the role of natural fractures in the migration path of CO₂ plume and geochemical reactions throughout the storage process. The study demonstrates that placing the injection well away from the top of the structure in a low-dip region while injecting in the bottom interval would yield the optimum design. After applying a plethora of analyses, geological complexity could impede the migration path of CO₂ but eventually produce a similar path when injected in a similar region. The geochemical interactions between the injected CO₂ and reservoir fluids and minerals reduce the free and trapped CO₂ quantities by dissolving calcite and precipitating dolomite. Furthermore, natural fractures impact the CO₂ quantities during early times only when the fractures cross the top layers. Similarly, the CO₂ migration differs due to the higher permeability within the fractures, resulting in slightly different CO₂ plumes. Consequently, the role of natural fractures should be limited in carbon storage projects, specifically if they do not cross the top of the reservoir. This study reflects a unique perspective on sequestering CO₂ while capturing the roles of natural fractures and well placement in depicting the migration path of the CO₂ plume. A similar systematic workflow and holistic approach can be utilized to optimize the subsurface storage process for potential formations. Full article

Mediterranean diet adherence has been decreasing during the last few decades, and non-appropriate snacking habits have also been identified among Mediterranean children and adolescents. To co-create new snacks and to explore children’s interests and preferences, a multi-method approach was used in the present study, including some qualitative and quantitative research phases. Conducted in collaboration with schools in Lebanon, Egypt, Portugal, Italy, and Spain, different snack prototypes were designed and tested in a Mediterranean cross-cultural context. The results showed significant differences among countries in snacking preferences and general food-related attitudes. Italian children exhibited higher levels of neophobia, resulting in lower acceptance of all proposed snacks. Some sensory and contextual insights were collected, such as Egyptian children favoring sweet and crunchy textures and “At school”, “With my friends”, and “As a morning/afternoon snack” being identified as linked to snack acceptance in some countries. The present study underscores the value of co-creation processes involving children to address non-recommended dietary patterns, highlighting the critical role of sensory properties, cultural differences, and contextual factors in designing healthy snacks that meet the Mediterranean diet’s principles but are highly appreciated by the young segment of the population. Full article

Moisture generation in the ventilation projects of deeply buried underground corridors affects the underground building environment and personnel health. In order to master the heat and humidity transfer law of underground corridors, this paper establishes a mathematical model by theoretical analysis, and the application of the theoretical model in engineering calculation is verified by a field test. It is found that the ventilation efficiency and heat and humidity transfer effect are related to corridor shape. The results show that under the same cross-sectional area, the average temperature drop and humidity of a rectangular corridor are 0.25% and 0.3% higher than that of an arch corridor, and 0.8% and 0.9% higher than that of a circular corridor. Under the condition of constant section circumference, the average temperature drop and humidity of a rectangular corridor are 0.51% and 0.62% higher than that of an arch corridor, and 1.37% and 1.58% higher than that of a circular corridor. When the equivalent diameter is the same, there is almost no difference in the heat and humidity transfer effect of the three shaped corridors. Full article

The study investigates controlled environment agriculture (CEA) in Nigeria focusing on its feasibility, economic benefits, environmental impact, and socio-economic implications. While CEA technologies such as hydroponics, vertical farming, automation, and greenhouse systems offer efficiency and yield improvements, this review highlights the extent to which they can be utilized in solving the food challenges facing the country including food shortages, wasteful use of land, and climatic disturbances in agriculture. However, their adoption faces challenges like high initial costs, technical knowledge gaps, and unstable energy infrastructure. Additionally, there is a lack of localized research on resource utilization, crop profitability, and the scalability of these systems in Nigeria’s urban and rural contexts, which further hinders adoption. Government policy reforms, renewable energy access, and capacity-building programs are crucial to overcoming these barriers. Localized pilot projects and field studies are also necessary to validate the feasibility of CEA systems under Nigeria’s unique socio-economic and climatic conditions. Cross-country comparisons with South Africa and Kenya reveal actionable insights for Nigeria’s CEA implementation such as South Africa’s public-private partnerships and Kenya’s solar-powered vertical farms which can serve as actionable blueprints for Nigeria’s CEA adoption and expansion. Nigeria with its teeming population is food import-dependent, with agricultural imports reaching 3.35 trillion Naira between 2019 and 2023. This is unsustainable and requires alternative measures including targeted CEA interventions to increase its agricultural productivity. Overall, for CEA to contribute meaningfully to the Nigerian agricultural sector, specific changes including targeted subsidies, policy reforms, renewable energy access, stakeholder engagement, capacity-building programs, and infrastructure development must be instituted to achieve sustainable agricultural growth. Furthermore, strategies such as hybridizing traditional and CEA practices and creating “pay-as-you-grow” financial models for CEA infrastructure can make the transition more viable for smallholder farmers, who dominate Nigeria’s agricultural sector. Full article

The hydrosphere is an element of the climate system and changes in the latter are reasonably projected over the river outflow. Climatic changes, however, are unevenly distributed over the Earth, and understanding their regional imprint on the hydrosphere is of great importance. In this study, we have conducted a statistical analysis of the monthly maximum and minimum river discharge recorded in 22 hydrological stations located on 19 of the Bulgarian rivers during the period 1993–2022. We have found that in half of the river basins, the trend of the spring maximum discharge is significantly positive (α = 0.05). In the other half of the stations, the trend is neutral. The stations with a positive trend are not randomly distributed but grouped, forming a pattern crossing the country from northwest to southeast. This pattern of trend distribution raises questions about the causes of the irregular hydrological response to the rising global near-surface temperatures. A comparison of hydrological data with some climatic variables (i.e., temperature, precipitation, and ozone at 70 hPa), combined with neural network analysis results, suggests ozone as a possible reason for the heterogeneous hydrological response. Its effect could be explained by an imposed episodic warming of the near-surface temperature due to fluctuations in the ozone density near the tropopause, which in turn favours the faster melting of ice and snow in the corresponding river basins. Full article

Teak [Tectona grandis L.f.] has a wide distribution range in tropical countries and is Nepal’s second most planted commercial tree species. This study aimed to develop a robust and reliable taper equation for Teak species in Nepal. To achieve this, 15 parametric taper equations were fitted and evaluated using the diameter and height data of 100 trees sampled from two stands of the Sagarnath Plantation projects, Nepal. The data set was split into training (90%) and testing (10%) sets based on the trees’ ID, and model fitting was conducted in two phases. In the first phase, nonlinear models were fitted to the training data using 10-fold cross-validation, and the performance was evaluated based on fit and validation statistics. The top five models were further analyzed in the second phase using a mixed effects framework to account for variance and correlation structures. The modified Bi model performed best under a fixed effects modeling framework (R² = 0.96, RMSE = 1.83 cm). However, the Sharma and Zhang model performed the best under a mixed-effects modeling framework (R² = 0.97, RMSE = 1.54 cm). Therefore, we suggest using the modified Bi under fixed effects and variable exponent equation of Sharma and Zhang under mixed-effects modeling as a taper equation for Teak. The Sharma and Zhang’s equation is recommended for its high accuracy and better performance over previously recommended variable exponents equations. Full article

Advanced construction techniques, such as additive manufacturing (AM) and modular construction, offer promising solutions to address labor shortages, reduce CO₂ emissions, and enhance material efficiency. Despite their potential, the adoption of these innovative methods is hindered by the construction industry’s fragmented expertise. Building Information Modeling (BIM) is frequently suggested to integrate this diverse knowledge, but existing BIM-based approaches lack a robust framework for systematically documenting and retrieving the cross-domain knowledge essential for construction projects. To bridge this gap, this paper presents an ontology-driven methodology for documenting and utilizing expert knowledge, with a focus on AM in construction. Based on a well-founded ontological framework, a set of modular ontologies is formalized for individual domains. Additionally, a prototypical documentation tool is developed to elevate recorded information and BIM models as a knowledge graph. This knowledge graph will interface with advanced large language models (LLMs), enabling effective question answering and knowledge retrieval. Full article

Adolescence is a phase characterized by reckless and risky behaviors, including the initiation and use of various illicit substances such as cannabis and alcohol. When ingested or administered, these substances affect mental processes by delivering pleasure, inner peace, and satisfaction. The aim of this study was to determine the prevalence and associated factors of psychoactive substance (PAS) use among adolescents. A cross-sectional study was conducted, including 300 participants surveyed using a structured questionnaire. Data were collected using the Mediterranean School Survey Project on Alcohol and Other Drugs (MedSPAD) to assess substance use, the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) to diagnose substance use disorders (SUDs), and the Early Trauma Inventory Self-Report Short Form (ETISR-SF) to identify childhood maltreatment, as well as socio-demographic characteristics. During the study period, 300 secondary school students participated. Their mean age was 17.92 ± 1.40 years, ranging from 15 to 22. There were slightly more males (56.7%) than females. A total of 40.67% of participants admitted to using at least one PAS at least once, while the prevalence of current use was 26%. Tobacco was the most commonly used substance (22.1%), followed by cannabis (7.33%). According to the DSM-5, 40.2% of users met the criteria for severe addiction. Factors associated with PAS use included the father’s level of education; place of use (e.g., home); poor relationships with parents, siblings, and teachers; and childhood maltreatment. Psychoactive substance use was found to be prevalent among adolescents in this study. Full article

The presence of isolated stones in the soil layers of engineering sites has significantly increased. Currently, the existing methods for dealing with isolated stones are inadequate to meet engineering needs. This paper combines pile-planting technology with isolated stones to incorporate them into the load-bearing system, resulting in a new type of pre-drilled composite pile suitable for isolated stone sites. A visualization testing system for pile-soil deformation is developed using Particle Image Velocimetry (PIV) technology and transparent soil, conducting non-intrusive model tests on pile-planting and boulder-capped piles under different uplift load conditions, and comparing the results with a discrete-continuous coupled three-dimensional numerical model analysis. The results indicate that when an isolated stone with a cross-sectional area four times that of the pile exists at the pile tip, the ultimate pullout bearing capacity of the pile increases by a factor of two. Regarding the distribution of internal and external side friction resistances of the core and outer concrete of the piles, the internal friction resistance of piles without isolated stones is approximately 1.47 times that of the external friction resistance and about 0.8 times the ratio of the diameters of the pile and core. For piles with isolated stones at the tip, the internal friction resistance is approximately 1.37 times that of the external friction resistance. Under the ultimate load, the displacement field around the pile without an isolated stone exhibits an “inverted triangular” distribution; the displacement field around the pile with an isolated stone at the tip exhibits a “trapezoidal” distribution. This study investigates the bearing capacity and load transfer mechanisms of the new pre-drilled composite piles in isolated stone engineering sites, and the research findings may provide new solutions for similar construction projects involving rubble reclamation. Full article

Background/Objectives: Internet use positively impacts mental health in older adults, with health literacy (HL) playing a key role. While social networks may complement individual HL, the role of neighborhood relationships in this association, particularly by gender, remains unclear. This study examined how the association between HL and Internet use among older adults was modified by neighborhood relationships. Methods: Using baseline data from the Chofu–Digital–Choju project, a cross-sectional analysis was conducted on 1955 community-dwelling adults aged 65–84 (889 men and 1066 women). HL was assessed using the Communicative and Critical Health Literacy scale and dichotomized at four points. Neighborhood relationships were categorized as high (visiting/chatting with neighbors) or low (exchanging greetings/no relationship). Gender-stratified logistic regression analyses were performed with Internet use as the dependent variable, with HL, neighborhood relationships, and their interaction as independent variables. Results: Internet user proportion was 55.6% for men and 41.8% for women. HL was positively associated with Internet use in both genders, though patterns differed. Among men, the HL–Internet use association was consistent (OR = 3.09; 95% CI: 2.25–4.24) regardless of neighborhood relationship levels. For women, this association was significantly modified (interaction OR = 0.46, 95% CI: 0.24–0.87). Women with low HL but strong neighborhood relationships showed increased odds of Internet use (OR = 2.08, 95% CI: 1.32–3.26). Conclusions: Gender-specific patterns in HL and neighborhood relationships influence Internet use among older adults. Neighborhood relationships may compensate for low HL in women, underscoring the need for gender-sensitive strategies to promote digital HL. Full article

Robotic construction using three-dimensional (3D) concrete printing (3DCP) offers significant potential to transform Kuwait’s construction industry, particularly in reducing waste. This study explores the feasibility of integrating 3DCP into Kuwait’s construction waste management practices by examining the perspectives of key stakeholders. Through a mixed method approach of a comprehensive literature review, a survey of 87 industry professionals, and 33 in-depth interviews with representatives from the Public Authority for Housing Welfare (PAHW), Municipality, private sector, and the general public, the study identifies both the benefits and challenges of 3DCP adoption. The findings highlight key advantages of 3DCP, including increased construction efficiency, cost savings, enhanced design flexibility, and reduced material waste. However, several barriers, such as regulatory limitations, technical challenges in adapting 3DCP to local project scales, and cultural resistance, must be addressed. Results also indicate varying levels of stakeholder familiarity with 3DCP and existing waste management practices, underscoring the need for awareness and educational initiatives. This study makes two significant contributions: first, by providing a detailed analysis of the technical and regulatory challenges specific to Kuwait’s construction sector, and second, by offering a strategic roadmap for 3DCP integration, including regulatory reform, research into sustainable materials, and cross-sector collaboration. These recommendations aim to enhance waste management practices by promoting more sustainable and efficient construction methods by achieving SDGs 9, 11, 12, and 13. The study concludes that government support and policy development will be essential in driving the adoption of 3DCP and achieving long-term environmental benefits in Kuwait’s construction industry. Full article