Search Results (39)

Background: The Kingdom of Saudi Arabia is adjacent to two vital marine ecosystems; the semi-enclosed Arabian Gulf and the largely landlocked Red Sea. Dinoflagellates are repeatedly found in these bodies of marine water, which serve as significant routes for cargo ships. Through these ships and ballast water, invasive dinoflagellate species and their cysts are introduced. They compete with indigenous species for nutrients and space, cause massive fish kill-off and disturb the ecological balance and biodiversity. To address these threats, the International Convention for the Control and Management of Ships’ Ballast Water and Sediments (BWM Convention) set forth guidelines intended to curtail the dissemination of such detrimental organisms. The Kingdom of Saudi Arabia was one of the co-signatory countries to this Convention. Methods of detection and monitoring include microscopy, molecular characterization and remote sensing, which are employed for the detection and monitoring of these harmful algae, in order to avert disasters such as fish die-offs. The results of several reports confirmed the presence of number of dinoflagellates in both the Arabian Gulf and the Red Sea, some of which are toxin producers, with certain species being highlighted as invasive species whose presence requires a high level of alert. Discussion: The monitoring, the change in engineering of cargo ships and the introduction of advanced surveillance methods, together with the proper treatments of ballast water, are all important security elements that ensure the safe disposal of ballast water without introducing harmful species. Full article

The study focuses on the T-shaped tunnel scenario with protective doors, performs explosion tests using aluminized explosives, and investigates the propagation patterns and loading characteristics of explosion shock waves in the straight tunnel, at the T-shaped junction, and within the semi-enclosed space in front of the protective door. It was observed that, in comparison to TNT explosives, the overpressure curve of aluminized explosives in the near-explosion zone exhibited a two- batch characteristic. The second batch presented the maximum overpressure peak. In contrast, in the far zone, the curve displayed a stable triangular waveform. In the main tunnel of the T-shaped opening with protective doors, it was found that the back blast surface located in front of the entrance to the main tunnel experienced the maximum momentum, which could be as high as 12 times greater than that of the reflection area on the blast-facing surface at the entrance of the main tunnel and the shock-wave pressure wave pattern can be divided into four batch. The regularities of each measurement point in multiple tests show consistency, highlighting the influence laws of the geometric structure on the wave pattern and load distribution. In addition, this paper integrates LS-DYNA numerical simulation with aerodynamics theory to reveal that shock waves generate expansion waves and oblique shock waves as they pass through the T-shaped opening. After two reflections off the main tunnel wall and the door, a stable propagation waveform is established. In addition, through dimensional analysis and in combination with the experimental results, the momentum at key positions was analyzed and predicted. This study offers a reference for the design of relevant engineering protection measures. Full article

University students are subject to various demands in their role as academics. Such pressures tend to amplify emotional distress, making them more susceptible to mental health hazards. This study investigates the influence of enclosed courtyards on students’ mental health within educational facilities, focusing on their distinct spatial configurations, such as semi-open layouts and vegetation cover, as well as their effects on intellectual functioning and well-being. The research used electroencephalography (EEG) to examine brainwave activity and quantify the influence of the spatial design of enclosed courtyards on the mental and emotional well-being of students. An experiment with 16 students and EEG measurements was conducted in the Faculty of Engineering courtyard at Egypt’s Ain Shams University in Cairo, providing 60–70% statistical power to detect medium effect sizes (Cohen’s d = 0.5, α = 0.05), which is sufficient for exploratory research. The study explores the psychophysiological implications of the brain’s electrical signals as neurological measurements, such as alpha and theta brainwaves, in order to assess individuals’ relaxation, restoration, and attention levels. The findings show that natural characteristics of the courtyard, expansive space, and visual stimuli have a significant effect on restoration and attention. While the sample size is limited and the design is context-specific, the results provide preliminary evidence that meticulously designed enclosed courtyards can improve students’ mental well-being. These findings invite further multi-site validation to assess generalizability. This study contributes to the expanding domain of neurolandscape” by demonstrating the interplay between built environments and mental health in educational contexts. Full article

To explore new methods for the conservation and utilization of traditional villages, a research path of “spatial distribution analysis–traditional village classification–pattern language identification” was constructed. First, the spatial distribution characteristics of traditional villages in Enshi Prefecture were analyzed. Then, the factors influencing the distribution characteristics were explored, and traditional village types were classified. Finally, the Production-Living-Ecological space pattern languages (PLES-PLs) of traditional villages were identified. The results show the following: (1) Traditional villages in Enshi Prefecture exhibit a clustered distribution at the macro level, mainly concentrated in the central and southwestern regions, but the distribution is unbalanced across counties and cities. (2) Five Production-Living-Ecological space pattern languages were identified, namely Nested Pattern, Ring-Shaped Pattern, Guided Pattern, Juxtaposed Pattern, Semi-Enclosed Pattern. Full article

A simulation study was conducted on the hydrogen leakage diffusion process and influencing factors of fuel cell vehicles in enclosed spaces. The results indicate that when hydrogen leakage flows towards the rear of the vehicle, it mainly flows along the rear wall of the space and diffuses to the surrounding areas. Setting ventilation openings of different areas on the top of the carriage did not significantly improve the spatial diffusion speed of the leaked hydrogen, and the impact on the concentration of leaked hydrogen was limited to the vicinity of the ventilation openings. The ventilation opening at the rear can accelerate the diffusion of hydrogen gas to the external environment, significantly reducing the concentration of hydrogen and rate of gas rise. When the leaked hydrogen gas flows towards the front of the vehicle and above the space, the concentration of hydrogen mainly increases along the height direction of the space. The research results have significant safety implications for the use of fuel cell semi-trailer trucks. Full article

Theaters in ancient Pompeii played a vital role in Roman entertainment, shaping the auditory experiences of spectators. This study examines the acoustic properties of the Amphitheater, the Grand Theater, and the Odeon using impulse response (IR) analysis to reconstruct their soundscapes. Next, the study considers the impact of typical musical instruments, vocal performances, and ambient sounds—such as gladiatorial combat—on these spaces’ acoustics. Findings reveal significant differences in reverberation times, sound clarity, and spatial characteristics, shaped by each theater’s design. These sites, preserved after the eruption of Mount Vesuvius, provide a unique opportunity to analyze how architecture influenced sound propagation. The Amphitheater, with its vast open structure, enhanced large-scale events, while the Grand Theater’s semi-enclosed design balanced musical and theatrical performances. The Odeon, the most intimate of the three, prioritized speech clarity. These insights highlight how Roman architects engineered performance spaces to accommodate diverse entertainment forms. By combining acoustic measurements with historical context, this research offers a deeper understanding of ancient Pompeii’s soundscapes and the auditory experiences of its inhabitants and offers insights for composition and soundscape creations that take inspiration from these prominent historical architectural and cultural icons whilst exploring its potential within contemporary immersive listening practices. Full article

This study collected site and spatial morphological data from 63 typical aging community activity spaces and extracted 12 spatial types through statistical analysis. A parametric modeling tool was used to generate spatial models. Based on clearly defined design variables and constraints, the NSGA-II multi-objective optimization algorithm was applied to minimize summer thermal discomfort, maximize winter thermal comfort, and maximize annual average sunlight duration, resulting in 342 Pareto optimal solutions. The study first explored the linear relationships between spatial morphology and environmental performance using the Spearman method. It then integrated ensemble learning and the interpretable machine learning model SHAP to reveal nonlinear relationships and boundary effects. The results of the two methods complemented and reinforced each other. Based on a comparison of these two approaches, morphological indicators showing significant differences were selected for attribution and sensitivity analyses, clarifying the mechanisms by which spatial morphological parameters influence environmental performance and identifying their critical thresholds. Key findings include the following: (1) the UTCI-S exhibits significant negative linear correlations with the open space ratio (OSR) and spatial crowding density (SCD); the UTCI-W shows negative linear correlations with canopy coverage (CVH) and wind speed (WS); and a positive linear correlation exists between the sky view factor (SVF) and AV.SH. (2) Boundary effects and threshold intervals of critical morphological parameters were identified as follows. The open space ratio should be controlled to 10–15%, the shrub–tree layer coverage to 0.013–0.0165%, and the average building height to 3.1–3.8 m. (3) Spatial layout principles demonstrate that placing fully enclosed spaces (E-2) and semi-enclosed spaces (S-1/S-3) on the northern side, as well as semi-enclosed spaces (S-1/S-2) and circulation spaces (C-3) on the southern side, significantly enhance microclimatic performance. These findings provide quantitative guidelines for community space design in cold regions and offer data support for creating outdoor environments that meet the comfort needs of the elderly. Full article

China’s urbanization process has entered the stage of mid-to-late transformation and upgrading, with the urbanization and population growth rates having passed the turning point. Urban renewal has become an increasingly important issue, among which the renovation of old residential areas holds enormous potential. The improvement of the living environment is urgent, and enhancing the microclimate to improve the livability and comfort of outdoor residential spaces is a critical factor. This study presents for the first time a quantitative framework for multifactor synergistic optimization by coupling building layout closure and material albedo effects. This paper takes typical old residential areas in Fuyang as an example and uses 3D microclimate simulation software (ENVI-met Version 4.3) to establish a simulation model. It evaluates the microclimate and thermal comfort under different building layouts, green infrastructures, building envelope materials, and various surface materials. The results show that: (1) Regarding building layout, the point-cluster layout generally results in the best improvement of daily cumulative physiological equivalent temperature (PET) values, followed by row-type and enclosed layouts; (2) The optimal solutions for improving the daily average PET value are as follows: using glass as the building envelope material in the point-cluster layout; 100% tree coverage in the row-type layout; and 100% asphalt coverage as the surface material in the point-cluster layout. These three conditions reduce the daily average PET by 3.51 °C, 23.87 °C, and 2.65 °C, respectively; (3) The degree of impact on PET is ranked as: green infrastructure configuration > building layout > building envelope materials > surface materials; (4) When the building layout of the residential area is more enclosed, such as using row-type or enclosed layouts, the order of building envelope materials improving thermal comfort is: brick, concrete, and glass. When the building layout is less enclosed, such as using point-cluster layouts, the order of building envelope materials improving thermal comfort is: glass, brick, and concrete. Therefore, it is concluded that applying point-cluster layout in buildings, using glass as the building envelope material, and having 100% coverage of asphalt pavement as the surface material and 100% coverage of trees can maximize the improvement of the thermal environment of the buildings. The conclusion is applicable to old residential areas in warm temperate semi-humid monsoon climatic zones characterized by high densities (floor area ratios > 2.5) and high rates of hardening of the ground (≥80%), and is particularly instructive for medium-sized urban renewal projects with an urbanization rate between 45% and 60%. Full article

This paper introduces a multi-indicator heuristic evaluation-based rapidly exploring random tree (MIHE-RRT) algorithm to address the key challenges of robot path planning in complex environments. The core innovation lies in a novel dual optimization framework that combines Hammersley sequence sampling with a comprehensive multi-indicator heuristic evaluation mechanism. The Hammersley sequence ensures uniform coverage of the configuration space, while the multi-indicator heuristic evaluation mechanism intelligently guides tree expansion through a three-dimensional evaluation system incorporating diversity, distance, and angle values. After generating the initial path, a pruning algorithm removes redundant points to produce an efficient and practical final path. Extensive experimental validation in four different environmental scenarios (semi-enclosed, maze, chaotic, and crowded) demonstrates that MIHE-RRT outperforms RRT (rapidly exploring random tree), IBi-RRT (improved bidirectional rapidly exploring random tree), and HB-RRT (halton biased rapidly exploring random tree) algorithms. Results show significant improvements in planning efficiency (54–88% reduction in execution time), path quality (15–24% shorter paths), and computational resource utilization (77–94% reduction in nodes). These excellent performance metrics not only prove MIHE-RRT’s advantages in complex environments but also make it particularly suitable for practical robot navigation applications requiring reliable and efficient path planning. Full article

Based on the relative lack of research on the acoustic characteristics of traditional Gan opera theaters, this paper takes the Zhaomutang theater in Leping, Jiangxi Province, as a case study. By employing impulse response measurements and sound quality index evaluation, this work investigates and analyzes the sound field characteristics of the stage, front patio, Xiangtang, rear patio, and Qintang through field measurements. The results show that the small volume and low ceiling in the stage area lead to higher early reflections and enhanced self-auditory support for performers. The semi-enclosed Xiangtang space exhibits the best speech definition and music clarity. Although the front and rear patios are open-air, they still maintain moderate reverberation and sound energy intensity due to reflections from surrounding surfaces. In contrast, the Qintang has a relatively weak early sound energy because of its volume and functional constraints. Still, its overall reverberation time is not significantly different from that in the other areas. Comprehensive indices indicate that the Zhaomutang theater balances speech intelligibility and musical richness for multifunctional scenarios—ancestor worship, opera performances, and gatherings—thus providing an enhanced viewing experience. These findings offer critical reference points for the protection, restoration, and acoustic optimization of Gan Opera ancestral temple theaters and provide an empirical foundation for further investigation into the multi-space coupling characteristics of traditional theaters. Full article

As global climate change intensifies, the frequency and severity of extreme weather events continue to rise. However, research on semi-outdoor and transitional spaces remains limited, and transportation stations are typically not fully enclosed. Therefore, it is crucial to gain a deeper understanding of the environmental needs of users in these spaces. This study employs machine learning (ML) algorithms and the SHAP (SHapley Additive exPlanations) methodology to identify and rank the critical factors influencing outdoor thermal comfort at tram stations. We collected microclimatic data from tram stations in Guangzhou, along with passenger comfort feedback, to construct a comprehensive dataset encompassing environmental parameters, individual perceptions, and design characteristics. A variety of ML models, including Extreme Gradient Boosting (XGB), Light Gradient Boosting Machine (LightGBM), Categorical Boosting (CatBoost), Random Forest (RF), and K-Nearest Neighbors (KNNs), were trained and validated, with SHAP analysis facilitating the ranking of significant factors. The results indicate that the LightGBM and CatBoost models performed exceptionally well, identifying key determinants such as relative humidity (RH), outdoor air temperature (Ta), mean radiant temperature (Tmrt), clothing insulation (Clo), gender, age, body mass index (BMI), and the location of the space occupied in the past 20 min prior to waiting (SOP20). Notably, the significance of physical parameters surpassed that of physiological and behavioral factors. This research provides clear strategic guidance for urban planners, public transport managers, and designers to enhance thermal comfort at tram stations while offering a data-driven approach to optimizing outdoor spaces and promoting sustainable urban development. Full article

The investigation of hydrogen leakage and diffusion behavior is of great importance for the assessment of safety risks and the establishment of safety regulations for hydrogen refueling stations. However, the uncertainty associated with the location of hydrogen leaks and the complex environment pose challenges in understanding the diffusion characteristics of hydrogen leaks. In this research, a numerical analysis is performed to study the diffusion of hydrogen leaks in both horizontal and vertical directions under three different environments, considering two different sizes of leak holes. The results show that horizontal and vertical hydrogen leaks have different effects on the hydrogen diffusion behavior. The presence of a canopy and obstacles inhibits hydrogen diffusion and dilution, which could be the cause of more severe accidents. Moreover, the size of the leak hole also impacts the scale of the flammable gas cloud. The effect of leaking direction to the canopy is also considered. In comparison with the semi-open space, the pressure on the canopy is higher in an enclosed space. Full article

Tomato cultivation is relatively dense, and the main stem is easily submerged in a background environment with small color difference. The semi-enclosed planting space and fast growth cycle are both limitations that cannot be ignored in detection technology. The accuracy and real-time performance of plant height detection are of great practical significance. To this end, we are committed to improving YOLOv5 and proposing a lightweight real-time detection method for plant height by combining visual features of tomato main stems. Here, we improved the backbone, neck, head, and activation functions of YOLOv5, using CSP dark net53-s as the backbone structure and introducing a focus structure to reduce the number of GE modules. We replaced all CSP2_X structures in neck and head with GE modules, embedded interactive multi-head attention, and replaced YOLOv5’s framework function and attention activation function. We defined visual features such as the color of the main stem of tomato plants in the preprocessed image; input improved YOLOv5; and completed plant height detection through effective feature map fusion, main stem framing, and scale conversion. The experimental results show that the linear deviation between the plant height detection value and the actual value of the proposed method is always less than 3 cm, and the detection FPS can reach up to 67 frames per second, with superior timeliness, which can effectively achieve lightweight real-time detection. Full article

This study examines how different primary school campus layouts impact the wind environment and classroom ventilation in Xi’an, using simulations for winter and summer conditions. It evaluates four typical floorplans to find the best for outdoor wind quality and classroom ventilation. During winter, the outdoor wind speed at a height of 1.5 m remains below 5 m/s, adhering to the Green Building Evaluation Standard (GB/T50378-2019). Notably, Scenario 1 achieves higher wind speeds due to the canyon effect between buildings, facilitating effective air renewal. The wind speed amplification factors in all scenarios are within the permissible limit of 2, while Scenario 1 demonstrates superior outdoor wind performance. Wind pressure differences on building surfaces remain within the 5 Pa limit, with Scenario 3 exhibiting the lowest difference of 0.74 Pa, contributing to energy-efficient heating. In summer, Scenario 1 uniquely avoids vortex areas and windless zones, ensuring efficient airflow across the campus. Its open floor planning prevents the formation of stagnant air zones, in contrast to Scenarios 2, 3, and 4, which create enclosed or semi-enclosed spaces promoting vortex formation and windless areas. These findings underscore the benefits of Scenario 1’s design in optimizing both winter and summer wind environments for energy efficiency and occupant comfort. This study recommends including adequately sized spaces in zigzag, branched, or enclosed floor plans to provide airflow and prevent high wind speeds. These results are crucial for shaping upcoming architectural plans to improve the environmental quality of school grounds, leading to improved health and comfort for students and teachers. Full article

With the expansion of Chinese university campuses, electric bikes (E-bikes) have become the most sustainable and effective commuting option because they are a flexible and energy-saving travel mode. Consequently, campus E-bike charging piles have become one of the most essential public service facilities on campuses. However, since most Chinese campuses are closed and independent, the principles of urban public service facilities cannot be simply applied to the layout and use of campus charging facilities. Thus, this study focuses on Zijingang Campus at Zhejiang University, and proposes an optimization strategy for the spatial and temporal layout of E-bike charging piles on the campus. First, trip chain demand models are constructed to examine the travel patterns of E-bike users on campus and the demands for charging areas and time. Second, a space location model is constructed to locate the charging piles in areas with high demand. Finally, according to the charging times of different users, user charging time is integrated into the strategy. This study enhances the layout and utilization system of campus E-bike charging facilities by considering both temporal and spatial dimensions. Overall, this study contributes to the advancement of sustainable transportation infrastructure planning on a campus-wide scale, offering theoretical insights for the design and utilization of functional facilities in large-scale, semi-enclosed environments (e.g., university campuses). Full article