The limited interior space in modern vehicles, driven by the adoption of EVs/HEVs and low-profile designs, necessitates new approaches to seat cushion design. Seat comfort relies on the load-deflection properties of polyurethane foam, which are difficult to predict due to their nonlinear behavior. To address this, we developed a series spring physical model to approximate these properties. Our findings show that this model's behavior aligns strongly with that of actual polyurethane foam, allowing its complex nonlinear properties to be accurately described by a simple exponential function. This model is applicable not only to foam samples but also to complex structures like full seat assemblies, offering a valuable tool for improving the efficiency of seat design and performance prediction.

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Rotating flow in corotating systems is modelled using non-axisymmetric configuration with inserted obstruction (arm) and a partial shroud opening. These kinds of systems exist in artificial hearts, turbomachinery, and hard disk drive (HDD), and they exhibit three-dimensional structure and fluid shear within their enclosed casing. In our study, we applied 2D-2C particle image velocimetry (PIV) to investigate planar flow physics in the model which portrayed an HDD used for information storage. While the flow has been extensively investigated in simplified axisymmetric models, there is a lack of sufficient results for non-axisymmetric configurations that more accurately represent conventional HDD geometries. Varying the inseretion angle of the arm between shallow and deep configurations, and at three measurement planes in the inter-disk 𝑟 − 𝑧 plane, the flow pattern exhibited different behaviour depending on the region upstream or downstream the inserted arm. Downstream, the flow transitioned at a critical radius (𝑟𝑐∗ ) between solid body rotation towards the edge of the hub and a sheared flow towards the edge of the disk. At the hubarm constricted region, an accelerated flow was formed with the deep arm insertion velocity matching, and exceeding disks local velocity further downstream, but the shallow insertion maintained a full solid body rotation towards the edge of the hub. At the upstream region of the inserted arm, a distinct pattern of the flow revealed a deceleration pattern.

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This paper presents a study on the optimal restructuring of distribution networks using MATLAB and the Binary Particle Swarm Optimization (BPSO) algorithm. The primary objectives are to minimize power losses and enhance power quality within the network. We employ the Binary PSO algorithm to address the complex problem of network reconfiguration, aiming to achieve efficient load distribution and improved reliability. Through extensive simulations and performance evaluations, our approach demonstrates the effectiveness of BPSO in achieving significant reductions in power losses and improvements in overall power quality. The results offer valuable insights into the practical application of advanced optimization techniques for enhancing the efficiency and reliability of distribution networks.

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Frequent urban pluvial flooding due to heavy rainfall has occurred in densely populated residential areas in Japan in recent years. In the 21st century, low-impact development (LID) as a stormwater management (SWM) strategy has been advocated by many countries in response to such events. The use of rain gardens (RGs), a typical LID design approach, can effectively reduce urban pluvial flooding. However, in our previous analytical study of RGs in Saitama City, a suburb of Tokyo, we found that ordinary RGs were only effective during initial peak rainfall, which we assumed was related to limited soil permeability and the absence of active water management. To improve the role of RGs in reducing flooding, this study proposes the concept of smart RGs (SRGs). SRGs are controlled by soil sensors that detect zones of optimal soil permeability and moisture levels and use intelligent valves to direct rainwater to those zones via an infiltration piping system. The intelligent valves adjust the water flow rate and distribution to maintain a balanced infiltration rate across the different zones. By linking the sensors and intelligent valves to local weather forecasts, the smart valves can increase the infiltration rates of SRGs before the onset of a rainstorm. This ensures that the SRGs can hold more rainwater when the rainstorm arrives. This study aimed to verify the effectiveness of SRGs in reducing urban pluvial flooding during continuous rainfall in Saitama City using pySWMM simulations. The effectiveness of the SRGs was measured using two dimensions: overflow volume and infiltration volume. SRGs reduced the total runoff volume from 6% to 17% compared to RGs and demonstrated a 17.36% increase in the total infiltration volume compared to regular RGs.

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Floods pose a significant threat to urban populations particularly those in low-lying areas, where evacuation routes can quickly become impassable. This case study focused on the 2015 Kanto–Tohoku heavy rain in Joso City to investigate the effect of residential geographic characteristics and evacuation routes on evacuation time and success during flood events. By integrating flood simulation data with a multiagent evacuation simulation model, this study evaluated evacuation feasibility across seven residential clusters, which have distinct topographical and hydrological features. It identified three key geographic factors as critical to evacuation outcomes: residential elevation, inundation from tributary flooding, and surrounding low-lying terrain. Clusters at higher elevations achieved high evacuation success rates despite delayed departure, while low-lying clusters exhibited high failure rates regardless of the route taken. Furthermore, clusters at higher elevations and farther from shelters highlighted the effectiveness of adaptive route selection strategies (evacuating inundated areas via the shortest possible route), which helped increase evacuation success rates and reduce evacuation times.

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Bridges are a critical component of urban development, and effective bridge management systems are essential to ensure their optimal functioning and maintenance. An effective bridge asset maintenance plan balances the importance of preventive maintenance with corrective maintenance. By implementing appropriate measures at the right time, effective maintenance planning can significantly reduce the costs associated with delayed or corrective (reactive) interventions. However, the adoption of maintenance strategies varies due to geographical factors and other regional constraints. This study aimed to understand the current practices and challenges in implementing maintenance plans for bridge infrastructure across developing countries. For this purpose, an interview survey was conducted with practitioners and managers from nine bridge maintenance departments in Bhutan, Ethiopia, Nepal, Thailand, and Pakistan. The responses, analyzed using the inductive coding method, helped identify critical issues and opportunities for improvement in bridge maintenance and management plans. A comparison of the responses revealed that, although some organizations implement elements of preventive maintenance, most agencies remain primarily reliant on corrective maintenance. The study identified several challenges common to both maintenance types, including the lack of dedicated budgets, insufficient data, and limited technical capacity. Furthermore, the absence of structured planning frameworks and the underutilization of inspection data continue to hinder the integration of proactive strategies into bridge maintenance planning.

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This study focuses on the Tsukishima district in Tokyo and employs a questionnaire-based approach to systematically examine residents' everyday greening practices, their intentions to install green curtains, and the associated motivations and barriers. The survey results indicate that 42.4% of respondents have implemented greening measures in their living spaces, driven primarily by motivations such as residential beautification and personal interest. In contrast, green curtains are more commonly perceived as functional environmental interventions, with temperature regulation being the most cited motivation, while concerns over insect infestation and reduced natural lighting serve as key obstacles. Further analysis reveals significant variations in green curtain installation intentions across different age groups and housing sizes: both younger and older residents exhibit higher willingness to install green curtains, and those living in more limited spaces are more inclined to adopt green curtain due to their potential environmental benefits. In comparison, awareness of environmental policies and greening event participation show no significant correlation with installation intention. In fact, the overall awareness of greening policies and participation in community greening activities remain low, suggesting that residents' greening behaviors are largely shaped by individual experience and personal needs, rather than policy guidance or collective engagement.

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The construction industry, particularly road construction, frequently suffers from schedule delays, cost overruns, and workflow inefficiencies. Traditional scheduling approaches reliant on static critical path methods have been found to be inadequate in fully managing the inherent variability and uncertainity of road construction and maintenance operations. In contrast, the Last Planner System, a key component of lean construction, promotes collaborative planning, constraint management, and continuous workflow improvement, offering a dynamic framework for enhancing project reliability and control. This research aims to assess the effectiveness of lean scheduling using the Last Planner System for under-construction and maintenance road projects. By leveraging empirical data from ongoing projects, the study evaluates the planning reliability, workflow efficiency, and scheduling performance using metrics such as Percent Plan Completed and Coefficient of Variance. The results revealed that maintenance projects showed greater fluctuation in Percent Plan Completed than underconstruction projects, underscoring the need for adaptive scheduling. This research offers practical insights for contractors, project managers, and public agencies aiming to optimize planning reliability, reduce waste, and improve infrastructure delivery.

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Klong Toey Market, a densely populated area in Thailand, has attracted many newcomers due to high labor demand. Shophouses and markets were constructed around the harbor to facilitate goods distribution, serving residences to workers. However, many of these shophouses are now deteriorating, negatively impacting residents’ living environments. This research aims to provide insights for owners and residents of shophouses, fostering awareness of current environmental conditions. The goal is to collaboratively develop solutions to improve housing quality. With many older shophouses in existence, a deeper understanding of maintenance and enhancement strategies is crucial for creating healthier living environments that align with contemporary lifestyles. In this study, the actual condition of the shophouse was clarified by detailed actual measurements and grasp the difficult situation of the living environment. Subsequently, data on the physical and interior environments of shophouses were collected, including temperature, relative humidity, carbon dioxide levels, and lighting, to identify specific issues. It was found that high temperatures typically coincide with lower relative humidity and elevated carbon dioxide concentrations, while high humidity can hinder air density, complicating carbon dioxide dispersion. Notably, high humidity can lower temperatures but create a sensation of warmth, underscoring the need for comprehensive data management due to the interrelated nature of these factors. The analysis emphasizes that natural air movement and ventilation are crucial for regulating conditions within shophouses. Carbon dioxide levels can vary significantly in areas with the same temperature, particularly where ventilation is poor. Enhancing natural ventilation can improve carbon dioxide dispersion, temperature control, and reduce excess moisture, ultimately increasing resident comfort. This research contributes to a broader effort toward resilient urban housing in high-density contexts.

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The growth in the number of tourists in cultural landscapes that shelter delicate ecosystems and preserve unique cultural identities addresses a theme of increasing concern around the world. The purpose of this study is to relate the spatial distribution of tourists in Taketomi Island with potential socio-environmental problems observed in the field during participant observation research. Using the application of a questionnaire directly with tourists and the projection of the results into official data from 2019, this study explored the relationship between tourists’ concentration and the cultural landscape’s vital systems by producing heat maps for different scenarios with varying visitors’ numbers. An uncontrolled scenario with a high number of visitors concentrating in the most visited spots was found to be potentially harmful to ecological balance and sociocultural prosperity in specific areas highlighted by the heat maps. This study suggests that limiting the number of tourists, investing in low impact infrastructure, and improving tourist turnover and flow could help to mitigate the negative impacts of tourism development in such an area. Further studies are needed to enhance the mapping methods and organically grasp the main variables connected to ecosystem preservation and cultural adaptation to the new tourism realities.

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The Li ethnic group on Hainan Island has developed unique architecture that reflects their customs and cultural heritage. However, traditional Li-style residences are rapidly declining, with many villages at risk of disappearing (Chen, 2020). This loss is driven by complex factors, making it urgent to find sustainable preservation methods. This study uses theoretical analysis, fieldwork, interviews, and 3D modeling to explore solutions for Bai-Cha Village. Field studies in 2023 examined settlement patterns, geomorphology, and local views on tourism. Interviews with residents and officials provided insights on living conditions and expectations. Applying rural sustainable development theory, the paper analyzes the evolution and decline of traditional Li houses and proposes preservation strategies, using Bai-Cha as a case study to protect Li architecture and cultural heritage.

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This study investigates the effects of ion exchange with alkaline earth metals (Mg, Ca, Sr, Ba) on the performance of faujasite (FAU) zeolite membranes for water/isopropyl alcohol (IPA) pervaporation. FAU zeolite powders and membranes were synthesized and modified through ion exchange. The structural changes were analyzed using XRD, N2 adsorption-desorption, zeta potential measurements, and energy dispersive Xray spectroscopy (EDS). Ion exchange significantly impacted the crystallinity, surface charge, and pore properties of the FAU zeolites. The increase in ionic radius of divalent ions increased the water separation factor in PV permeation of IPA solutions from 7.474 to 4590. The ion exchange increased the d-value of the [111] plane of the FAU crystal, which is due to the suppression of permeation through the grain boundaries of the FAU membrane. The results provide insights into how ion exchange modifications affect the separation performance of FAU zeolite membranes for water/IPA pervaporation.

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Pervaporation (PV) is an effective separation technique that utilizes membrane technology to selectively extract alcohol from aqueous solutions through hydrophobic MFI (Mobil-Five) membranes. The performance of these zeolite membranes was influenced by polarity and molecular sieving. This study explored the use of hexamethyldisiloxane (HMDSO) for post-treatment of MFI membranes to enhance their surface properties and separation efficiency. Evaluating various treatment temperatures revealed that increasing the temperature improved membrane thickness and hydrophobicity, evidenced by decreased alcohol permeance and increased water contact angles. The ethanol-water PV system demonstrated higher permeance than the methanol-water system due to ethanol's lower polarity and better adsorption on hydrophobic membranes. The optimal HMDSO treatment was found at 200 °C for 2 hours, achieving a separation factor of 26.5—approximately double that of untreated membranes—while higher temperatures reduced separation performance. This research highlighted the potential of HMDSO treatment for improving MFI membrane efficiency in PV applications.

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The aim of the present study was to determine the content of flavonoids, phenolics, saponins and alkaloids, as well as the antioxidant function of Artemisia vulgaris extract using a simple and fast colorimetric technique. Particularly, the subclasses of flavonoids as they have been reported to possess remarkable pharmacological importance. The extract was prepared by ultrasound assisted extraction in 70% ethanol. The colorimetric assays showed that the ethanolic A. vulgaris extract contained phenolics (41.527 ± 2.658 mg GAE/g), saponin (52.176 ± 9.927 mg EE/g) and alkaloid (4.335 ± 1.613 mg CAE/g). The total flavonoid contents were 18.562 ± 8.547 mg NE/g and 7.536 ± 0.351 mg QE/g using 2,4-dinitrophenylhydrazine (DNPH) and aluminium chloride methods, respectively. However, UHPLCMS/MS detected mostly glycosylated flavonols and flavones in the plant extract. The presence of ketones and aldehydes in other compounds could possibly cause overestimation in the result of DNPH assasy. The presence of bioactive compounds proven enhancing the peroxyl radical scavenging ability of A. vulgaris extract. Therefore, the plant extract could be a natural source f bioactive ingredient for the development of innovative and functional foods.

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Positive affect supports well-being, resilience, learning, and social functioning. However, assessment in applied settings often depends on self-reports that can be unreliable or unavailable for people who struggle to recognize or express emotions. Therefore, this study examines the practical utility of physiological indices for assessing high- and low-arousal positive affect (HAPA, LAPA) within participants. In a controlled experiment, videos induced HAPA and LAPA across multiple trials per participant. We collected selfreported HAPA and LAPA scores alongside electroencephalography (EEG) and heart rate variability (HRV) data. Standard EEG band powers and several HRV metrics, including pNN10, were caluclated over stimulus intervals, and within-participant associations with self-reports were estimated using repeatedmeasures correlation. Results were limited to pNN10: a small positive association with HAPA and a small negative association with LAPA; other HRV indices. Findings suggest pNN10 offers modest, useful information to support self-report in practice.

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The idea of strong stability of linear time invariant systems has been introduced by Karcanias, N., Halikias, G., and Papageorgiou, A. (2010), which is a stricter condition compared to traditional definitions, Lyapunov, and asymptotic stability. In this paper, we consider robust stability and stabilization based on the concept of strong stability. Assuming that there is norm-bounded uncertainty in the linear system, we design a state feedback non-overshooting controller via linear matrix inequality (LMI) approach.

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Currently, responsiveness and reduced lead times are not only desirable attributes for make-toorder businesses, but they are also important for maketo-stock businesses looking to grow their long-term competitiveness. One of the challenges facing the production managers is changeover time, which needs to be addressed. This study aims at demonstrating how the SMED methodology may be used to decrease changeover time in the production process at the X plant, which is a typical fertilizer company in Vietnam. With the implementation, the changeover time is reduced by approximately 37.48%, from 707 minutes to 442 minutes. By differentiating between external and internal setup work, converting internal setups to external ones, and optimizing the entire process, the study identifies important inefficiencies and provides targeted fixes. These include rearranged process steps, quicker sample analysis methods, and enhanced cleaning equipment, all of which contributed to enhanced production efficiency. Overall, this study highlights the managerial value of SMED, stressing the need of using data to identify bottlenecks, standardizing processes to ensure consistency, and encouraging a continuous improvement mindset through ongoing analysis. Fertilizer production facilities can significantly increase production efficiency and overall performance by implementing this strategy across departments.

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