Search Results (1,476)

Tourism is a fast-growing sector that generates a significant greenhouse gas (GHG) footprint, yet subnational data needed to measure the sector remain scarce. Quantifying tourism-related emissions is essential for effective climate policy and alignment with international targets. This study contributes to quantifying tourism sector GHG emissions using the 2023 Korean National Travel Survey data and a spend-based environmentally extended input–output (EEIO) model. Expenditure data were mapped onto the 33-sector multiregional EEIO framework, estimating a total of 2623 tCO_2eq emissions by region, expenditure type, and industry sector in 2023, where about 73% of the total was attributed to tourism-related sectors with the sample data, 24,282. The results illustrate how tourism emissions are shaped especially by transportation systems and regional context. Provinces that surround metropolitan cities in the mainland, for example, Gyeonggi and Gangwon Provinces near Seoul and Incheon, and Gyeongnam Province neighboring Busan and Ulsan, record higher emissions due to large travel volumes from these metropolitan cities and energy-intensive transportation services. Jeju Island stands out as an outlier, with disproportionately high emissions relative to its size, driven by reliance on aviation, which significantly raises its per-visitor footprint. Sectoral analysis identified transportation services, agriculture, electricity, and gas as key sectors. By providing detailed provincial-level data, this study offers a first empirical foundation to corporate Category 6 of Scope 3 reporting and supports central and local governments in designing region-specific climate strategies associated with tourism-related sectors. Full article

Fingerplate expansion joints are commonly used in bridges to accommodate large movements in bridge decks, often due to thermal expansion or contraction. Although these joints are designed to last the bridge’s lifetime, they have experienced premature degradation under high-volume vehicular loads. Damage to these joints can compromise structural integrity and endanger public safety. To address this, a series of experimental fatigue tests were conducted to simulate cyclic vehicular loading, with the goal of identifying the controlling failure modes and refining design practices for fingerplate expansion joints. The study involved constructing fingerplate joint specimens based on standard Missouri Department of Transportation (MoDOT) designs, incorporating three design variables: fingerplate thickness, flange stiffeners, and concrete embedment. Additionally, two optimized designs were developed and tested under both fatigue and static loading conditions. Two distinct failure types were observed in the specimens. Specimens with flange stiffeners experienced fatigue failure, characterized by crack propagation through the back weld of the fingerplate to the supporting beam. In contrast, specimens without flange stiffeners failed due to serviceability issues, as they could not sustain the required load before reaching the maximum allowable deformation, leading to buckling of the supporting beam’s top flange. The optimized designs showed no fatigue degradation and exhibited increased ultimate strengths compared to the standard MoDOT designs. Overall, a thicker fingerplate improved the stiffness and fatigue performance of the expansion joint, while bolted connections effectively eliminated the crack propagation fatigue failure observed in many specimens and in the field. Full article

This study investigated the electrolytic-plasma hardening (EPH) of cast 20GL steel, used for railway spring beams. The main objective was to analyze the spectral characteristics of the cathodic discharge and establish correlations between the plasma parameters, processing regimes, and resulting surface properties. Optical emission spectroscopy revealed that the plasma at 260 V exhibited a high-energy state with an electron density of ~5.3 × 10¹⁶ cm⁻³ and an electron temperature of 10,031 K. Using these parameters, the heat flux from the plasma to the steel surface was estimated at ~1.5 × 10⁷ W/m², confirming that the discharge provides sufficient energy for surface austenitization. Microstructural analysis demonstrated that the electrolyte flow rate, which determines the cooling rate, is the key parameter controlling phase transformations. At low flow rates, ferrite–pearlite and bainitic structures formed, while a fully martensitic structure and maximum hardness (1046 HV) were achieved at 10 L/min. Tribological tests confirmed the superior wear resistance of the martensitic layers, showing a friction coefficient of 0.454 and a wear volume 3.4 times lower than in the as-cast state. These findings verify that EPH offers an energy-efficient, low-cost method for improving the surface performance and service life of 20GL steel components in heavy-duty railway applications. Full article

The memory demand of modern applications has been rapidly increasing with the continuous growth of data volume across industrial and academic domains. As a result, computing devices (i.e., IoT devices, smartphones, and tablets) often experience memory shortages that degrade system performance and quality of service by wasting CPU cycles and energy. Thus, most operating systems rely on the swap mechanism to mitigate the memory shortage situation in advance, even if the swap memory fragmentation problem occurs over time. In this paper, we analyze the fragmentation behavior of the swap memory space within storage devices over time and demonstrate that the latency of swap operations increases significantly under aged conditions. We also propose a new extension of the traditional swap mechanism, called VSwap, that mitigates the swap memory fragmentation problem in advance by introducing two core techniques, virtual migration and address remapping. In VSwap, virtual migration gathers valid swap pages scattered across multiple clusters into contiguous regions within the swap memory space, while address remapping updates the corresponding page table entries to preserve consistency after migration. For experiments, we enable VSwap on the traditional swap mechanism (i.e., kswapd) by implementing it with simple code modifications. To confirm the effectiveness of VSwap, we performed a comprehensive evaluation based on various workloads. Our evaluation results confirm that VSwap is more useful and highly valuable than the original swap mechanism. In particular, VSwap improves the overall performance up to 48.18% by harvesting available swap memory space in advance with negligible overhead; it performs close to the ideal performance. Full article

Pollinators play a crucial role in global biodiversity, providing essential ecosystem services such as crop pollination. However, their abundance and diversity have been gradually decreasing in recent years. Despite increasing interest in sustainable agriculture, information on vegetable crops that attract insect pollinators remains limited. We hypothesize that variation in floral traits among vegetable crop cultivars, especially nectar volume, nectar sugar concentration, and pollen characteristics, significantly influences visitation patterns and species composition. To test this, we evaluated multiple cultivars of six vegetable crops (cowpea, sweet potato, eggplant, green bean, mustard, and chickpea) over two years, focusing on five key pollinator groups (honey bees, bumble bees, carpenter bees, sweat bees, and wasps). Cowpea and sweet potato consistently attracted the most pollinators, whereas chickpea attracted the fewest. In 2022, nectar volume was highest in sweet potato (16.45 ± 0.37 µL) and lowest in chickpea (1.18 ± 0.75 µL). Similarly, in 2023, sweet potato recorded the highest nectar volume (8.33 ± 2.95 µL), and chickpea the lowest (0.02 ± 0.01 µL). However, chickpea (31.00 ± 1.58 °Bx) and mustard (30.10 ± 1.12 °Bx) recorded the highest nectar sugar concentration in both years, and chickpea and eggplant produced significantly more pollen grains. A significant positive correlation was observed between nectar volume and pollinator abundance. Comprehensively, this two-year study demonstrates the complex relationship between floral traits and pollinator preferences. These findings offer growers practical guidance on selecting vegetable intercrops that attract specific pollinators, thereby enhancing pollination services, supporting biodiversity, and improving the yield of pollinator-dependent crops. Full article

Increasing traffic volumes, heavier axle loads, and the growing frequency of premature pavement distress pose major challenges for modern road infrastructure. In many regions, asphalt pavements experience early rutting, cracking, and moisture-induced damage, underscoring the need for improved material performance and longer service life. Reinforcing fibres are increasingly used to enhance asphalt mixture properties, with aramid fibres recognised for their superior mechanical and thermal stability. This study evaluates the effect of FlexForce (FF) fibres on the mechanical and fracture behaviour of two dense-graded asphalt concretes, AC 16 surf and AC 16 bin, produced with different binders and fibre dosages (0.02% and 0.04% by mixture weight). Laboratory tests, including indirect tensile strength ratio (ITSR), indirect tensile stiffness modulus (IT-CY), crack propagation resistance, and dynamic modulus measurements, were performed to assess moisture susceptibility, stiffness, and viscoelastic behaviour. The results showed that fibre addition had little effect on compactability and stiffness under standard conditions but improved temperature stability and stiffness at elevated temperatures, particularly when used with polymer-modified binders. Moisture resistance decreased slightly, while fracture performance improved moderately at intermediate temperatures. Overall, low fibre dosages (~0.02%) provided the most balanced performance, indicating that the mechanical benefits of aramid reinforcement depend strongly on binder rheology, temperature, and interfacial compatibility. These findings contribute to optimising fibre dosage and binder selection for aramid-reinforced asphalt layers in practice. Full article

Street greening is widely recognized as influencing resident well-being and housing prices, and street-view imagery provides a fine-grained data source for quantifying urban microenvironments. However, existing research predominantly relies on single indicators such as the Green View Index (GVI) and overall green coverage/volume lacking a systematic analysis of how the hierarchical structure of trees, shrubs, and grass relates to housing prices. This study examines the high-density block context of Tianjin’s six urban districts. Using the Street Greening Space Structure (SGSS) dataset to construct greening structure configurations, we integrate housing-price data, neighborhood attributes, and 13,280 street-view images from the study area. We quantify how “visibility and hierarchical ratios” are capitalized on in the housing market and identify auditable threshold ranges and contextual gating. We propose an urban–forest structural system centered on visibility and hierarchical ratios that links street-level observability to ecosystem services. Employing an integrated framework combining Geographical-XGBoost (G-XGBoost) and SHapley Additive exPlanations (SHAP), we move beyond average effects to reveal structural detail and contextual heterogeneity in capitalization. Our findings indicate that tree visibility G_TVI is the most robust and readily capitalized price signal: when G_TVI increases from approximately 0.06 to 0.12–0.16, housing prices rise by about 8%–10%. Hierarchical structure is crucial: balanced tree–shrub ratios and moderate shrub–grass ratios translate “visible green” into functional green. Capitalization effects are environmentally conditioned—more pronounced along corridors with high centrality and accessibility—and are likewise common in dense East Asian metropolises (e.g., Beijing, Shanghai, Seoul, and Tokyo) and rapidly motorizing cities (e.g., Bangkok and Jakarta). These patterns suggest parametric prescriptions that prioritize canopy-corridor continuity and keep ratios within actionable threshold bands. We translate these findings into urban greening strategies that prioritize canopy continuity, under-canopy permeability, and maintainability, providing sustainability-oriented, parameterized guidance for converting urban greening structure into ecological capital for sustainable cities. Full article

Silicone rubber, primarily composed of polydimethylsiloxane (PDMS) chains, is widely used in sealing materials due to its excellent flexibility and durability. Its performance is significantly affected by environmental conditions, with humid-heat aging being a major factor of degradation. In this study, molecular dynamics simulations were conducted to systematically investigate the effects of water and temperature on PDMS at the molecular scale. The glass transition temperature (T_g) and free volume distribution were analyzed to evaluate the mobility of polymer chains under hydrated conditions. Mechanical simulations (including tensile and compressive deformation) indicate that the combined effect of elevated temperature and moisture significantly accelerates the degradation of rubber properties. Thermal decomposition simulations indicate that, under high-temperature and humid conditions, PDMS main chains gradually break into small molecules, with free radical reactions further promoting the aging process. The results elucidate the molecular mechanisms underlying silicone rubber performance deterioration under the coupled action of water and temperature, providing a theoretical basis for service-life prediction and durability design of sealing materials. Full article

This study examines the evolution of the Yellow River Basin’s urban corporate network from 2003 to 2023, aiming to understand how intercity connectivity and decision-making authority have developed. Using headquarters–subsidiary linkages of listed firms, we measure connectivity and control of cities within the urban system and employ spatial error models to identify their main determinants. The results show that the network has become denser and more geographically inclusive, especially in the middle and lower reaches. However, a clear hierarchy remains, and upstream integration stays limited. Community structures are anchored by capitals, and multi-core patterns strengthen over time. Coastal hubs in Shandong handle the most significant volumes of ties, while interior capitals such as Zhengzhou, Lanzhou, Xi’an, and Taiyuan concentrate authority—a contrast that has intensified since 2013. Connectivity and control often diverge, and disparities in both have increased. Administrative rank remains the strongest predictor of a city’s position, although its influence has decreased as factors such as openness, development, producer services, and innovation have gained importance. Transportation accessibility and human capital consistently support both connectivity and control, while government intervention initially restricts network roles but becomes less influential over time. These findings suggest that intercity corporate linkages have expanded, yet decision-making authority has not dispersed and remains concentrated in a small set of capitals. Governance that coordinates across provinces is necessary to ensure that increasing linkages translate into shared economic opportunities while protecting the basin’s fragile ecological environment. Full article

With the increasing demand for energy conservation and emission reduction in the automotive industry, optimizing the performance of cylinder liner and piston ring pairs in engines has become crucial. Aluminum–silicon alloy cylinder liners, known for their lightweight and excellent thermal conductivity, have emerged as a new trend in cylinder liner materials. Given the relatively moderate hardness of Al-Si alloys, judicious selection of piston rings is imperative to ensure optimal performance. This study investigates the tribological properties of aluminum–silicon alloy cylinder liners paired with CKS and DLC piston rings. The surface morphology and hardness of the test materials were characterized, and reciprocating friction and wear tests were conducted, using a tribometer to simulate operating conditions. The friction coefficient and wear volume were used as indicators to evaluate the tribological properties of the piston rings. The results show that, when the aluminum–silicon alloy cylinder liner was paired with a DLC piston ring, the friction coefficient was 27.82% lower, and the wear volume of the cylinder liner was 83.52% lower, compared to pairing with a CKS piston ring. When paired with a CKS piston ring, wear was exacerbated because silicon particles were easily dislodged to form abrasive particles. This particle detachment is mainly caused by the collision between the fine ceramic particles embedded in the CKS coating and the silicon particles (≤5 μm) uniformly distributed in the Al-Si alloy cylinder liner during the sliding process. The DLC piston ring, containing both sp² and sp³ hybridized carbon–carbon bonds, combined excellent lubrication properties with high hardness, resulting in minimal wear on both the cylinder liner and piston ring. Specifically, the DLC coating has a hardness of 2300 HV_0.3, which is 2.42 times that of the CKS piston ring (950 HV_0.3); the sp³-hybridized carbon in the DLC coating enhances its wear resistance to resist scratching from silicon particles in the cylinder liner, while the sp²-hybridized carbon forms a graphite-like transfer layer at the friction interface to reduce frictional resistance. In conclusion, the aluminum–silicon alloy cylinder liner paired with a DLC piston ring exhibits superior tribological properties. Selecting an appropriate piston ring can significantly enhance the tribological properties of the cylinder liner–piston ring pair, thereby extending the engine’s service life. Full article

In this study, iron ore tailings (IOTs) with different mass replacement rates (0%, 20%, 40%, 60%, 80%, 100%) and basalt fibers (BFs) with different volume contents (0, 0.1%, 0.2%, 0.3%) were co-incorporated into recycled concrete. To better simulate real-world conditions, a coupled carbonation–freeze–thaw cycling test was performed on C30 cubic specimens. Each test cycle comprised 7 days of carbonation followed by 25 freeze–thaw cycles, with four total cycles conducted. For specimens subjected to different numbers of test cycles, measurements were taken of the recycled concrete’s variations in mass, dynamic elastic modulus, and compressive strength. Scanning electron microscopy (SEM) was employed to examine the microscopic morphology of concrete under the test conditions and to analyze the mechanism through which the two materials influence the durability of recycled concrete in the experimental environment. Based on the Weibull distribution, a damage prediction model for basalt fiber iron ore tailing recycled concrete (BF-IOT-RAC) under the test environment was developed, and the service life of BF-IOT-RAC in Northwest China was predicted. The results indicate that the two materials can enhance the performance of recycled concrete when their dosages are appropriate; however, excessive dosages exert adverse effects. BF1T40 had a mass loss rate of 1%, an RDEM of 92%, and the cube compressive strength of 33.5 MPa at the conclusion of this test, with all three indicators being higher than those of recycled concrete with a single material incorporated. SEM observations revealed that the surface of BF1T40 was more intact than that of other recycled concretes after the test. According to the prediction, BF1T40 has the longest service life in the northwest region, reaching 42–43 years. Full article

This study examined the impact of a shift schedule change on firefighter sleep and health outcomes (n = 24). Firefighters from a U.S. department transitioned from a 24 h on, 48 h off (24/48) schedule to a 48 h on, 96 h off (48/96) schedule. Wrist actigraphy and self-reported health outcomes were assessed at three time points: baseline (24/48), 3 months post-transition, and 6 months post-transition. Objective sleep measures included total sleep time (TST), sleep efficiency (SE), sleep onset latency (SOL), and wake after sleep onset (WASO). Self-reported health outcomes included the Insomnia Severity Index (ISI), Beck Depression Inventory–II (BDI-II), Beck Anxiety Inventory (BAI), Multidimensional Assessment of Fatigue (MAF), and the Alcohol Use Disorders Identification Test (AUDIT). Linear mixed-effects models (LMMs) with random intercepts were used to evaluate changes over time, adjusting for age, years of service, and individual night-time call volume. Results showed significant improvements in TST, SE, SOL, and WASO at the 3-month follow-up, which were sustained but did not further increase at 6 months. ISI and BDI-II scores also improved, while BAI, MAF, and AUDIT remained stable. These findings suggest that the 48/96 schedule may provide short-term improvements in sleep and psychological health for firefighters in low call-volume settings. Additional research is needed in higher-volume departments and over longer timeframes. Full article

To ensure the transition to electric transport in order to reduce CO₂ emissions, a number of projects have been initiated to develop and introduce new types of locally produced vehicles. The Russian Federation market is quite conservative and has its own specifics and a special consumer model. In addition, the component base of localized components for electric vehicles is relatively small, which is justified by relatively low demand and market volumes. To create the concept of a Class C passenger vehicle with electric traction, marketing research was conducted in a group of people who are potentially ready to abandon traditional vehicles and choose electric vehicles or hybrids. The purpose of the study is to evaluate the opinion of consumers and to form the technical characteristics of a Class C hybrid car based on localized components. Methods: To obtain the results, various components of the power unit were modeled, and a balanced solution was found that meets the requirements of consumers in the region. Mathematical modeling was carried out and analytical studies of the power reserve of various configurations of power units within the WLTC cycle were carried out in the digital environment of Siemens Amesim. Analytical work on the study of the composition of cars for calculating the masses of modern components and aggregates was carried out using Autodatas. Consumer opinions were assessed through a survey using the Yandex. Forms service. The relevance of the study is confirmed by the lack of domestic models of sequential hybrids on the market and the lack of similar studies, based on the opinion of a potential consumer. The result is the technical parameters of the main components and assemblies, which should ensure the optimal cost of the final product and meet the requirements of the consumer. Conclusion: As a result of the study, a concept of a combined sequential-type power unit was developed based on available components, meeting the main consumer properties, and the technical characteristics of the components were presented. Full article

Background/Objectives: India’s private healthcare sector remains fragmented, with weak primary care, uneven secondary services, and tertiary care accessible to few. Fee-for-service payments and indemnity-style insurance distort prices and fragment accountability. This paper develops a conceptual, theory-driven framework for integrating financing and delivery so that prices reflect social opportunity costs and competition rewards value rather than volume. Methods: A comparative synthesis of international integration models covering Israel, the United States, Spain, Brazil, and the United Kingdom was undertaken. Each exemplar was analysed for ownership form, market maturity, and regulatory capacity, and interpreted using four strategic management theories: Contingency theory, the Resource-based view, Dynamic capabilities, and Institutional theory. These perspectives were combined to construct a contingency-based typology tailored to India’s mixed health system. Results: Two state-contingent integration pathways emerged. Hospital-first vertical integration suits hospital-dense, high-growth states such as Tamil Nadu and Delhi, where capital and regulatory depth permit managed-care scaling. Primary-care-first reverse integration is preferable in resource-constrained contexts such as Bihar and Chhattisgarh, leveraging community trust and lower capital intensity. Conclusions: Achieving universal health coverage in India requires regulatory conditions, such as ownership flexibility, solvency oversight, risk adjustment, and transparent outcomes reporting, to enable accountable payer–provider organisations to form. The framework extends contingency theory to mixed health systems and offers a transferable blueprint for emerging markets seeking sustainable, integrated managed care. Full article

Real-time control of web traffic is a critical issue for network operators and service providers. It helps ensure robust service and avoid service interruptions, which has an important financial impact. However, due to the high speed and volume of actual internet traffic, standard multivariate time series models are inadequate for ensuring efficient real-time traffic management. In this paper we introduce a new model for functional time series analysis, developed by combining a local linear smoothing approach with an $L^1$-robust estimator of the quantile’s derivative. It constitutes an alternative, robust estimator for functional modal regression that is adequate to handle the stochastic volatility of high-frequency of web traffic data. The mathematical support of the new model is established under functional dependent case. The asymptotic analysis emphasizes the functional structure of the data, the functional feature of the model, and the stochastic characteristics of the underlying time-varying process. We evaluate the effectiveness of our proposed model using comprehensive simulations and real-data application. The computational results illustrate the superiority of the nonparametric functional model over the existing conventional methods in web traffic modeling. Full article