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Decarbonizing economies requires an energy transition from conventional energy resources to renewable and clean energy resources. However, this transition largely depends upon the availability of huge investments to manage high start‐up costs and operational infrastructure. In this respect, the financial sector can play a vital role. This study explores the financial sector's role in renewable energy consumption utilizing a comprehensive measure of financial sector development constituting both financial institutions and financial markets. Moreover, the study utilizes an advanced econometric technique “dynamic panel threshold model” on panel data of 165 countries ranging from 1980 to 2019. The empirical analysis reveals the presence of a threshold value of 0.191, 0.196, and 0.008 for the overall financial development index, financial institutions index, and financial market index, respectively. This finding confirms the presence of a U‐shaped curve between financial sector development and renewable energy consumption, validating the existence of the financial Kuznets curve. Thus, initially, financial sector development results in lower renewable energy consumption while after reaching the threshold level it boosts renewable energy consumption. Furthermore, the study also shows the statistically significant role of economic growth, trade openness, and inflation in explaining renewable energy usage. The obtained outcomes suggest a pressing necessity to improve both financial institutions and markets to surpass the threshold levels of financial sector performance within the financial sector, thus supporting a rise in renewable energy consumption. [ABSTRACT FROM AUTHOR]

The Yangtze River Basin serves as an essential ecological shelter in China, yet it has encountered escalating aquatic ecological challenges. Exploring the spatial–temporal changes and the trade-off–synergy relationships of water-related ecosystem services (WESs) is necessary for formulating management and planning policies targeting the sustainable development of watersheds. In this study, the InVEST model is utilized to evaluate the spatial–temporal variations in water yield (WY), water purification (WP), and soil conservation (SC) in the Yangtze River Basin using remote-sensed data from 2001 to 2021. The spatial overlay method and a correlation analysis were adopted to reveal the trade-off–synergy relationship among the three WESs. Additionally, we performed a comparative analysis across the grid and sub-basin scales. The results showed that the multi-year average WY, WP, and SC were 536.10 mm, 1.32 kg/ha, and 250.08 t/ha, representing increasing rates of 4.74 mm/a, −0.001 kg/ha/a, and 1.88 t/ha/a, respectively. Moreover, the trade-off–synergy relationships of WESs exhibited spatial variability; specifically, the WY-WP, WP-SC, and WY-SC pairs demonstrated reduced synergy magnitude over time. The WES interactions were stable across the scales of interest, while synergy strength showed noticeable variability. The findings may contribute to the sustainable development of the Yangtze River Basin and enhance the comprehensive management of WESs. [ABSTRACT FROM AUTHOR]

In order to study the scale effect in wave-structure interactions and the role that structure-related parameters (tension T or bending stiffness EI) plays, riser model tests under regular waves were conducted using the model with multiple geometric scales (1:15, 1:12 and 1:9) in a wave basin. The riser model used is a novel structural design combing the outer polyvinyl chloride pipe with the core steel rod which could be simplified as a cantilever beam. Different initial tension T acting on the riser are tested by adjusting the slotted weight. The results show that the amplitude varies in a cubic fashion with the distance from the fixed end. In addition, the influence of the wave period and top tension T on the amplitude are investigated, which ultimately leads to a dimensionless number π1 = KCd·TL²/EI where KC is the classical Keulegan-Carpenter number (KC), EI shows the bending stiffness of the riser model and L gives the pipe length. With the KC number revised to take the distance from the fixed end into the calculation, this parameter provides a good measure in estimating the amplitudes of the riser vibrations induced by the waves. [ABSTRACT FROM AUTHOR]

Purpose: Hoping to uncover the physical principles of the vibration of the functionally graded material (FGM) microplate, by which the authors can make contributions to the design and manufacturing process in factories like micro-electro-mechanical system (MEMS) and other industries. Design/methodology/approach: The authors design a method by establishing a reasonable mathematical model of the physical microplate composed of a porous FGM. Findings: The authors discover that the porosity, the distributions of porosity, the power law of the FGM and the length-to-thickness ratio all affect the natural frequency of the vibration of the microplate, but in different ways. Originality/value: Originally proposed a model of the micro FGM plate considering the different distributions of the porosity and scale effect and analyzed the vibration frequency of it. [ABSTRACT FROM AUTHOR]

We consider the problem of deformation of a layered rectangle whose lower side is rigidly clamped, a distributed normal load acts on the upper side, and the lateral sides are in conditions of sliding termination. One-parameter gradient elasticity theory is used to account for the scale effects. The boundary conditions on the lateral faces allow us to use separation of variables. The displacements and mechanical loads are expanded in Fourier series. To find the harmonics of displacements, we have a system of two fourth order differential equations. We seek a solution to the system of differential equations by using the elastic potential of displacements and find the unknown integration constants by satisfying the boundary and transmission conditions for the harmonics of displacements. Considering some particular examples, we calculate the horizontal and vertical distribution of displacements as well as the couple and total stresses of a layered rectangle. We exhibit the difference between the distributions of displacements and stresses which are found on using the solutions to the problem in the classical and gradient formulations. Also, we show that the total stresses have a small jump on the transmission line due to the fact that, in accord with the gradient elasticity theory, not the total stresses, but the components of the load vectors should be continuous on the transmission line. Furthermore, we reveal a significant influence of the increase of the scale parameter on the changes of the values of displacements and total and couple stresses. [ABSTRACT FROM AUTHOR]

Based on the data of 2015 China Household Finance Survey (CHFS), this paper applies the intermediary effect model to identify the intermediate transmission mechanism in which farmland transfers affect agricultural production efficiency. The results show that the output value of households that have transferred farmland is increased by about 27% more than those that have not. In addition, the transfer of farmland has a more significant impact on the agricultural production efficiency of young and middle --aged families. The transfer of farmland from grain production areas has an increased tendency to household output value. The mechanism analysis shows that the transfer of farmland affects agricultural production efficiency in the following two ways. On the one hand, the transfer of farmland can help realize the effective replacement of labor by machinery, increase the mechanization degree of agricultural production, and realize the scale effect of farmland. On the other hand, based on the maximization of their own interests, farmers prefer to plant cash crops and improve agricultural production efficiency through the selection effect. By comparing the above two effects, we found that the planting selection behavior of compacting grain and expanding economic growth is more prominent. Therefore, this article proposes to promote the development of the farmland transfer market and make use of scale advantage. Meanwhile, the self-selection behavior of transferred farmers in planting crops should be valued and young people with advanced concepts to engage in agricultural production activities should be introduced, which inject "fresh blood" into agricultural modernization. However, we should also keep the red line of farmland and alert the phenomenon of "non-agricultural" and "non-grain" in the transfer of farmland. [ABSTRACT FROM AUTHOR]

Variables that can be considered in experimental investigations of internal instability of earth dam materials are often bounded by practicality and feasibility constraints. To overcome these shortcomings, a total of 164 previous published experimental results were compiled to study statistically the relative significance of vertical effective stress, grain size ratio (D15/d85), fines content, coefficient of uniformity (Cu), and specimen length in the mechanism of internal instability. The present statistical results agreed with previous experimental findings on the combined dominant roles played by fines content and stress in the internal instability. However, the stress reduction factor was found to be inversely correlated with the vertical effective stress, which was not reported previously. The scale effect of specimen size has significant positive correlations with both the stress reduction factor and critical hydraulic gradient, whereas the influences of Cu and D15/d85 were minimal, in contrast to previous experimental findings. An improved theoretical hydromechanical envelope for predicting internal instability of cohesionless soil in the space of stress-gradient–stress reduction factor was proposed in this study. The unstable envelope moved with increasing applied hydraulic gradient until the state of material touching the envelope. [ABSTRACT FROM AUTHOR]

Grasping the interrelationship between the supply and demand of ecosystem services (ESs) and spatial scale characteristics is the foundation for effective ecological zoning management, which helps to realize a win–win situation for both ecological protection and economic development. This paper focuses on the following three real problems: mismatch in ES supply and demand evaluation, mechanical and subjective delineation of ecological zoning, and rough management strategies, and constructs a multi-scale ecological zoning management framework for the "comprehensive evaluation of supply and demand, ecological zoning, and enhancement of human well-being". This study integrates the InVEST model, SOM, Z-score quadrant matching, and coordination degree method, and applies them to the ecological management zoning of Hangzhou. The results show that (1) the spatial differentiation of ESs in Hangzhou is significant. The spatial pattern of the five types of ES supply varies at the county scale and the grid scale on which ES demand is concentrated and is consistent at different scales. (2) ES supply–demand matching in Hangzhou is at the basic coordination and can be divided into four modes including HH, LH, LL, and HL at both the county and grid scales. On the small scale, the proportion of mismatches declines slightly, but the severity rises. (3) ES supply is divided into four categories as follows: the food production bundle, the carbon storage bundle, the ESs balancing bundle, and the ESs depleting bundle, and clarifies the priority of ES management. (4) Construct an ecological management practice path, delineates 6 ecological management zones at the county scale and 19 secondary management zones at the grid scale. Targeted measures are proposed in terms of supply–demand adjustment strategies, ecological management strategies, and key implementation areas. This study helps to incorporate the interaction between the supply and demand of ESs into the planning framework and provides decision-making support for refined ecological management. [ABSTRACT FROM AUTHOR]

Economic agglomeration has played a key function in China's economic transformation. Meanwhile, structural adjustment and external pressure to reduce carbon emission necessitate a deeper investigation into its relationship with carbon productivity. This paper measures economic agglomeration and carbon productivity of 281 cities in China in 2003–2017. With the purpose of exploring the spatial effect of economic agglomeration on carbon productivity, a spatial Durbin model is constructed. In addition, the mediation effect model is also adopted for examining the transmission mechanism of economic scale and technological progress on economic agglomeration as well as carbon productivity. A heterogeneity test is also carried out to uncover the varying effects of economic agglomeration on carbon productivity. The empirical results suggest that economic agglomeration raises carbon productivity not only in the local cities but also in the neighbouring ones. The impact of economic agglomeration on carbon productivity becomes more potent as the level of economic agglomeration increases. For cities with low level of economic agglomeration, the effect is mainly achieved through the expansion of economic scale, but for cities with high level of economic agglomeration, the effect is mainly achieved through technological progress. Therefore, we suggest encouraging carbon productivity improvement through technology effect in cities with high economic agglomeration level, while enhancing carbon productivity through scale effect in cities with low economic agglomeration level. [ABSTRACT FROM AUTHOR]

At present, titanium alloy/carbon fiber reinforced polymer (TA1/CFRP) laminates, representing the latest fourth generation of fiber metal laminates (FMLs), are predominantly applied in the field of aerospace. The miniaturization of traditional FMLs in thickness or plane size to the micron level for the study of structural properties of ultra-thin laminates will further expand the application of FMLs in the field of micro-devices. Given that carbon nanotubes have a strengthening mechanism in polymers. However, most existing studies have focused on the effect of carbon nanotubes on the properties of macro-scale FMLs, while the enhancement mechanism of the interfacial and mechanical properties of ultra-thin micro-scale FMLs has not been studied, leaving the mechanism still unclear. Based on this, this paper explores the interfacial deformation mode, damage fracture and performance enhancement mechanism of the ultra-thin TA1/CFRP laminates by comparing the parameters of tensile strength and elongation under quasi-static conditions and different process parameters of multi-walled carbon nanotubes content, test temperature, geometry size and grain size. Meanwhile, the correlation law between high-speed tension and quasi-static tension is determined, a 29.3 % increase in tensile strength as the strain rate rises from 0.001 s−1 to 100 s−1, yielding the basic deformation law of ultra-thin FMLs.

Accurately identifying the optimal spatial scales of effect analysis of influencing factors on water quality is crucial for effective water environment management. To address this, we propose a framework that consists of mix scale division (watersheds, riparian buffers, and circular buffers), and conduct a case study in the Yuanjiang River Basin (YJRB). Scale effects and non-linear impacts of various influencing factors on water quality were identified. The case study results revealed the variations of these water quality indicators were predominated by different influencing factors at various sales, such as by slope (SL) at the scale of riparian buffer (w) = 500 m and circular buffer (r) = 15 km (with a contribution percentage of 16.6 %), mean annual temperature (TE) at the watershed scale (23.4 %), annual precipitation (PR) at the scale of w = watershed and r = 15 km etc. The percentage of cultivated land (CL) > 28 % at the scale (w = 500 m, r = 50 km) will lead to increase in total phosphorus (TP) and SL > 26° at the scale (w = 500 m, r = 15 km) will lead to increase in pondus hydrogenii (pH). While, POP > 30 person per unit area at the scale (w = 100 m, r = 1 km), SL > 24° at the scale (w = 500 m, r = 15 km), NDVI > 0.48 at the scale (w = 500 m, r = 5 km) and PR > 1300 mm at the scale (w = watershed, r = 15 km) will lead to decrease in ammonia nitrogen (NH3-N), total nitrogen (TN), electrical conductivity (EC) and turbidity (NTU) respectively. Results indicated that the precision can be improved by regulating influencing factors within scale effects and considering the non-linear effects of factors on water quality.

Amidst swift socioeconomic progress, urbanization is intensifying, necessitating robust methodologies for environmental quality monitoring. Landscape Ecological Risk (LER) has emerged as a pivotal tool in this context. Extensive research has focused on the land utilization rates within watersheds, scrutinizing them through the lens of land use/land cover (LULC) dynamics. This study delves into the LULC attributes of the Bosten Lake Basin (BLB) across three temporal snapshots: 2000, 2010, and 2020. Grasslands and bare ground made up the vast majority area of the BLB. Selected twelve landscape pattern indices, analyzed their response curves with respect to grain size, determined the optimal grain size to be 150 m, and analysed its optimum amplitude of 10 km × 10 km on the basis of the semi-variance function, thus determined the optimal scale for analyzing the landscape pattern. Exploring scale effect facilitates a nuanced examination of the landscape patterns and land use efficacy within BLB. From 2000 to 2020, the landscape pattern showed less fragmented, less aggregated, and more spatially heterogeneous. The landscape ecological risk index model has been constructed for the investigation of the LER change characteristics of the BLB. Lowest-risk zones and lower-risk zones of LER predominate in BLB. In 2000, 2010 and 2020 the combined lower and lowest risk zones represent 62.02 %, 59.37 % and 58.44 % of the catchment area respectively. Finally, analyzed the spatial autocorrelation variation characteristics of LER. The global Moran' I index of BLB for the three periods from 2000 to 2020 exceeded 0.7. This study establishes theoretical and practical foundation for future multi-scale landscape ecological risk studies in eco-fragile regions.

This paper investigates possibilities of reducing production inefficiency using same input vector. Firms mostly suffer technical inefficiency in their production. Producers are found to operate below the frontier. Hence, empirical measures of production efficiencies are necessary to determine the inefficiency level, magnitude of inefficiency reduction, and gains that could be obtained by improving performance in the sector. The study used secondary data collected from Food and Agriculture Organization (FAO) and the National Bureau of Statistics (NBS) database. The dataset covers the period 1960-2021. Variables extracted included agricultural GDP (kg), fertiliser usage (kg), agricultural labour(man-days), and number of tractors (No). The data were subjected to a unit root test for stationarity, and a stochastic frontier production/ Cost function model were applied to determine technical inefficiency of variables in the model. The result of unit root shows that series are integrated of the first order I (1). AIC criteria indicate an optimal lag length of two years, while the Unrestricted Co-integration Trace and Maximum Eigenvalue test show strong evidence of long-run relationship amongst variables. The parameters of Stochastic Frontier Production Function estimated were positively consistent with the study’s a priori expectation for such variables as fertiliser (0.2634), labour (0.3159), land (0.1846), and tractor (0. 1587). Output-oriented technical efficiency is 0.7802 (78%) and 22% is technically inefficient. A decreasing returns to scale value of (0.9226) with a scale effect of 0.9226. The sector is 58% economically efficient with cost savings of 42% and 75% allocative efficiency. This study concludes that Nigeria’s agriculture suffers from production inefficiencies and this inefficiency can be reduced by using the same input levels.

The joint roughness coefficient (JRC), introduced in Barton (1973) represented a new method in rock mechanics and rock engineering to deal with problems related to joint roughness and shear strength estimation. It has the advantages of its simple form, easy estimation, and explicit consideration of scale effects, which make it the most widely accepted parameter for roughness quantification since it was proposed. As a result, JRC has attracted the attention of many scholars who have developed JRC-related methods in many areas, such as geological engineering, multidisciplinary geosciences, mining mineral processing, civil engineering, environmental engineering, and water resources. Because of such a developing trend, an overview of JRC is presented here to provide a clear perspective on the concepts, methods, applications, and trends related to its extensions. This review mainly introduces the origin and connotation of JRC, JRC-related roughness measurement, JRC estimation methods, JRC-based roughness characteristics investigation, JRC-based rock joint property description, JRC's influence on rock mass properties, and JRC-based rock engineering applications. Moreover, the representativeness of the joint samples and the determination of the sampling interval for rock joint roughness measurements are discussed. In the future, the existing JRC-related methods will likely be further improved and extended in rock engineering.

Satellite-derived Land Surface Temperature (LST) plays an important role in research on natural energy balance and water cycle. Considering the tradeoff between spatial and temporal resolutions, accurate fine-resolution LST must be obtained through the use of LST downscaling (DLST) technology. Various methods have been proposed for DLST at fine resolutions (e.g., 10 m) and small scales. However, the scale effect of these methods, which is inherent to DLST processes at different extents, has rarely been addressed, thus limiting their application. In this study, a modified daily 10 m resolution DLST method based on Google Earth Engine, called mDTSG, is proposed in order to reduce the scale effect at fine spatial resolutions. The proposed method introduces a convolution-based moving window into the DLST process for the fusion of different remote sensing data. The performance of the modified method is compared with the original method in six regions characterized by various extents and landscape heterogeneity. The results show that the scale effect is significant in the DLST process at fine resolutions across extents ranging from 100 km2 to 22,500 km2. Compared with the original method, mDTSG can effectively reduce the LST value differences between tile edges, especially when considering large extents (>22,500 km2) with an average R2 improvement of 33.75%. The average MAE is 1.63 °C, and the average RMSE is 2.3 °C in the mDTSG results, when compared with independent remote sensing products across the six regions. A comparison with in situ observations also shows promising results, with an MAE of 2.03 °C and an RMSE of 2.63 °C. These findings highlight the robustness and scalability of the mDTSG method, making it a valuable tool for fine-resolution LST applications in diverse and extensive landscapes.

In the modified formula for the cubic law, the roughness correction coefficient C serves as a parameter that indicates the characteristics of the roughness of a rock’s surface. In this study, surface data for natural rock samples were acquired through high-precision 3D scanning and combined with publicly accessible CT scan data on rough rock fractures to generate spatial coordinates. The roughness correction coefficient C was calculated and analyzed using both formulaic and numerical methods. The analysis revealed significant effects of scale on the roughness correction coefficient for rock fractures within a size range of 5 to 10 cm (determined based on the actual sample size), with tensile fractures demonstrating greater variations compared to shear fractures. When calculating the roughness correction coefficient on the same fracture surface in different directions, significant directional effects were observed. Furthermore, elliptical fitting demonstrated favorable results. The conclusion drawn was that the roughness correction coefficient for fracture surfaces can be represented effectively using a tensor form, thereby simplifying the expression of directionality. Calculating and analyzing the fractal dimension of a rough surface further confirmed the existence of effects of size on roughness.

In this paper, we proposed a method of introducing globally uniaxial strain into SOI(silicon-on-insulator) wafers, and the strain mechanism was discussed. Based on the size effect of internal-stress of SiN film, uniaxial strain was introduced in SOI layer by the formation of SiN bar array which width and the spacing were 1.5 μm and 3.0 μm on the whole surface of He+ implanted SOI wafer. Polarized Raman spectroscopy was adopted to reveal the uniaxial character of the introduced strain. In the crystallographic orientation of [100] and [110], uniaxially tensile strain of 0.7613% and 0.5125% was achieved respectively. [ABSTRACT FROM AUTHOR]

Few studies provide direct evidences that agricultural fiscal affects agricultural carbon intensity. This study tries to fill this gap. Using panel data of 30 provinces in China from 2005 to 2019, we conclude that agricultural fiscal expenditures significantly reduce agricultural carbon intensity. The result is still robust after employing the provincial agricultural leaders' birthplace information as an instrumental variable. Further study shows that the negative effect of agricultural fiscal expenditures on agricultural carbon intensity is more pronounced in regions with less corruption and is also more visible in central, western, and inland regions than other areas. For this effect, agricultural technological improvement and structure optimization are possible channels, but not operation scale expansion. Interestingly, although agricultural fiscal expenditures reduce the local agricultural carbon intensity, neighbor regions' carbon intensities are increased due to fiscal rivalry. [ABSTRACT FROM AUTHOR]

Slant range geometry plays a crucial role in interpreting synthetic aperture radar (SAR) observations, especially in converting line-of-sight (LOS) surface deformations to actual vertical subsidence. This paper proposes a new conversion model to retrieve vertical settlements of the embankment slopes using the geometrical parameters of the dam and the SAR sensor. The simulation results highlight the impact of slope foreshortening and heading direction of the satellite on deformation retrieval. Various SAR data with different resolutions and bands are used to analyze the model's performance, revealing a high conformity of the model with practical conversion parameters exceeding 80% for TerraSAR-X and Cosmo-SkyMed data. [ABSTRACT FROM AUTHOR]

The assumption of an isotropic material behaviour is still common practice for tunnel design. Strictly speaking, this assumption is only valid if the influence of directional dependencies on the resulting deformations and stresses is marginal. In lithologies that have a high degree of anisotropy, such as shales and phyllites, the orientation characteristics of material properties such as strength and stiffness should be taken into account in order to avoid serious misinterpretations of the bearing capacity and deformation characteristic of the surrounding rock and the tunnel lining. The main focus is to accurately distinguish between the different types and terminology of anisotropy. [ABSTRACT FROM AUTHOR]

In the present study, the added resistance, heave, and pitch of the KRISO Container Ship (KCS) in waves, at both model scale and full scale, are predicted numerically in regular head waves, for four wavelengths and three wave heights. The ISIS-CFD viscous flow solver, implemented in the Fidelity Fine Marine software provided by CADENCE, was employed for the numerical simulations. The spatial discretization was based on the finite volume method using an unstructured grid. The unsteady Reynolds-averaged Navier–Stokes (RANS) equations were solved numerically, with the turbulence modeled by shear stress transport (k-ω) (SST). The free-surface capturing was based on the volume-of-fluid method. The computed solutions were validated through comparisons with towing test data available in the public domain. To predict the uncertainties in the numerical solution, a systematic grid convergence study based on the Richardson extrapolation method was performed for a single wave case on three different grid resolutions. Specific attention was given to the free-surface and wake flow in the propeller plane. The purpose was to compare the numerical results from the model- and full-scale tests to examine the scale's effect on the ship's performance in regular head waves. The comparison between the model scale and full scale showed obvious differences, less accentuated for the free-surface topology and clearly observed in terms of boundary layer formation in the propeller's vicinity. [ABSTRACT FROM AUTHOR]

Rural tourism serves as a crucial means for fostering rural economic prosperity and inheriting rural culture. The assessment of the quality of rural tourism development and the identification of disparities in rural tourism development among regions have become focal points in current research. This paper utilizes tourism big data to establish a system for evaluating rural tourism popularity and proposes a method for identifying rural tourism hotspots. The study explores the spatiotemporal evolution characteristics and formation mechanisms of the cold and hot patterns of rural tourism in China during two periods (pre-pandemic and post-pandemic) and on two spatial scales (provincial and municipal levels). The research findings indicate that (1) the annual variation in rural tourism popularity exhibits a fluctuating upward trend, with significant seasonal variations on a monthly basis. (2) The spatial pattern of rural tourism popularity changes with the scale effect. At the provincial level, hotspot areas form an east–west dual-core pattern, while at the municipal level, hotspot areas demonstrate an evolution from a three-core to a four-core pattern. In the post-pandemic era, rural tourism popularity in the northwest and southwest regions is experiencing a counter-trend growth. (3) At different spatiotemporal scales, influencing factors and their impact intensities vary. At the provincial level, road density and reception capacity consistently play dominant roles, and per capita disposable income significantly influences early-stage popularity enhancement. At the municipal level, resident population and tourism resources influence are the dominant factors, and the influence of air quality and regional media attention gradually strengthens. This article provides a new perspective on quantitative research in rural tourism, offering significant guidance for the rational allocation of resources in rural tourism, regional tourism collaboration, and the sustainable development of rural tourism in the post-pandemic era. [ABSTRACT FROM AUTHOR]

Power transformers are critical equipment responsible for the transmission and transformation of electrical energy, and they are an important component of power system. Under the combined effects of electric field, thermal field, and mechanical stress, insulation degradation is prone to occur in oil-paper insulation structures. Among them, the "liquid-solid" interface formed by oil and oil-immersed pressboard is the weak point in transformer insulation, and extensive operational experience has shown that creeping flashover of insulating pressboard is a common fault in power transformers. Creeping flashover of insulating pressboard can rapidly destroy the insulation structure, leading to irreversible damage to the transformer and posing a serious risk of transformer accidents. In recent years, many scholars have conducted in-depth research on the characteristics and mechanisms of creeping flashover in oil-paper insulation structures using various experimental methods. They have obtained significant findings that have important theoretical and practical implications for optimizing the structure of power transformers and improving their reliability. This paper first introduces the characteristics of the electromagnetic environment inside the power transformer and the common forms of creeping flashover accidents in engineering. Then, classified according to the uneven degree of electric field and creepage distance of test electrodes used in relevant research, and the test methods and flashover characteristics of small size (<5 cm) and large size insulating pressboard under extremely uneven and slightly uneven electric fields are introduced respectively. Secondly, the existing breakdown model and mechanism theory of oil-paper insulation structure creeping flashover are summarized. Finally, the limitations of the existing creeping flashover test method of insulating pressboard are analysed, and the key issues to be solved are condensed. This review aims to provide readers with a comprehensive overview of the test methods, characteristics, and mechanisms of insulating pressboard creeping flashover. [ABSTRACT FROM AUTHOR]

Floods pose a significant threat to the safety of countries with severe societal, economic, and environmental consequences, especially the flash floods in mountainous regions. Previous studies have shown that many floods were caused by intense rainfall with highly saturated soil. In this study, we applied a physically-based distributed hydrological model (Integrated Hydrology Model, InHM) to a warm humid mountainous catchment in Southwest China, the Shouxi River. The main objective of our research is to investigate the relative importance of rainfall and antecedent soil moisture on flood generation in our study region. Our results show that an increase in rainfall return period and antecedent soil saturation ratio significantly increased peak flow and shortened peak time. There is a correlation between the ratio of antecedent soil saturation ratio to rainfall (SPR) and peak flow. When SPR <1, there is a positive correlation; when SPR >1, there is a negative correlation. Additionally, with the increase in drainage area, the relative importance of rainfall tends to decrease, while the relative contribution of soil saturation ratio tends to increase. The findings could provide support for the determination of the dominant factors influencing runoff generation in humid regions, offering scientific support for the timely and effective flood prevention and mitigation measures in mountainous regions. [ABSTRACT FROM AUTHOR]

This study examines the effects of globalization on environmental quality, explicitly focusing on the scale, technique, and composition aspects proposed by KOF Swiss Economic Institute. A large sample of 115 developed and developing countries is analyzed to understand how different dimensions of globalization impact environmental degradation at various levels, using the quantile regression method. The results indicate that globalization has a positive effect on emissions at lower and middle quantiles, but at the upper quantiles, the effect becomes negative, based on the distribution of CO2 per capita (CO2PC). Additionally, each dimension of globalization has its influence on emissions: (i) Renewable energy consumption significantly negatively impacts environmental quality across most percentiles, except for the 90th percentile. (ii) Foreign direct investment inflows positively affect environmental quality at lower quantiles but negatively at higher quantiles. (iii) Urbanization initially correlates negatively with environmental degradation at the 50th percentile, but this relationship turns positive at the 75th percentile. Overall, globalization benefits countries facing environmental degradation seriously, while countries maintaining a high quality environment have not benefited much from globalization. These findings offer valuable insights for policymakers in developing effective environmental policies considering diverse economic and environmental conditions across countries. [ABSTRACT FROM AUTHOR]

Non-grain cultivated land is distributed in the areas with a concentrated population and frequent mining activities in recent years, particularly with the continuous development of urban expansion and industrialization. The scale effect of nongrain cultivated land can be one of the most important geographic phenomena in spatial heterogeneity. The optimal strength of related factors can also be conducive to the sustainable production of cultivated land in the mineral grain composite areas. In this study, the aggregation and dispersion of non-grain cultivated land were considered in the different geographic scale units from the scale effect and spatial contiguity. The study area was taken as the largest copper mine and grain composite area in Jiangxi Province of China. Nine factors were selected considering the scale of 500-6100m block, watershed, and administrative village. The spatial measurement model was used to analyze the type of non-grain cultivated land in the mineral grain composite area. Firstly, the land survey data was used to quantify the non-grain cultivated land in 2020. Global Moran's I index was used to test the multi-scale spatial autocorrelation of three types of non-grain cultivated land in the mineral grain composite area. The block scale was classified into four scale levels; Then, the ordinary least square (OLS), spatial lag, and spatial error models were used to carry out the binary simulation regression of non-food cultivated land and the related factors. A comparison was made on the strength of the influencing factors at different scales. The results show that: (1) three forms of nongrain cultivated land were distributed mainly in the central and western regions, as well as the riparian zones with less distribution in the mountainous areas. The overall distribution of non-grain cultivated land showed strong spatial autocorrelation and strong spatial heterogeneity, with significant spatial spillover effects at most scales; (2) The outstanding scale effects were found in the spatial heterogeneity of non-grain cultivated land in the mineral grain composite area. Four zones were divided, according to the actual situation. (3) There was an inconsistent significance of related factors of non-grain cultivated land in different scales. The significant rate was 90.2% in the regression of non-grain cultivated land on the small scale, with an average value of the R² 0.236, which was better than other scales. The scale of the catchment area was better than that of administrative villages; (4) There was also a clear scale effect in the strength of related factors in the non-grain cultivated land, indicating the most significant in the small-scale level. the average regression coefficient of the main factors was greater than 0.25, and the significant rate reached 92%. Therefore, the cultivated non-grain cultivated land in the mineral grain composite area was affected by multi-scale, multi-factors, and multi-dimensions. The influence of related factors at different scales was the optimal choice to solve the cultivated non-grain cultivation. It is necessary to consider the spatial dependence and scale effect in the existence of non-grain arable land in the future comprehensive land space improvement in the mineral grain composite area. The key factors should also be optimized for the land space, according to local conditions. [ABSTRACT FROM AUTHOR]

This paper aims to show the scale effects of vertical maneuvering derivatives for an underwater vehicle using computational fluid dynamics (CFD). The model scale and full-scale benchmark DARPA suboff hull forms were used in numerical vertical planar motion mechanism simulations to achieve this aim. The heave forces, pitch moments, and Euler coefficients are calculated together with the linear vertical maneuvering derivatives by implementing the Fourier series expansion approach. The results show that the coupled added mass terms are significantly influenced by the scale effects, whereas the impact of scale effects on the decoupled added mass and coupled and decoupled damping terms is negligible. Considering that the effects of the coupled added mass on the vertical maneuvering characteristics are almost negligible, the vertical maneuvering of a submarine is slightly influenced by the scale effects. [ABSTRACT FROM AUTHOR]

This paper investigates possibilities of reducing production inefficiency using same input vector. Firms mostly suffer technical inefficiency in their production. Producers are found to operate below the frontier. Hence, empirical measures of production efficiencies are necessary to determine the inefficiency level, magnitude of inefficiency reduction, and gains that could be obtained by improving performance in the sector. The study used secondary data collected from Food and Agriculture Organization (FAO) and the National Bureau of Statistics (NBS) database. The dataset covers the period 1960-2021. Variables extracted included agricultural GDP (kg), fertiliser usage (kg), agricultural labour(man-days), and number of tractors (No). The data were subjected to a unit root test for stationarity, and a stochastic frontier production/Cost function model were applied to determine technical inefficiency of variables in the model. The result of unit root shows that series are integrated of the first order I (1). AIC criteria indicate an optimal lag length of two years, while the Unrestricted Co-integration Trace and Maximum Eigenvalue test show strong evidence of long-run relationship amongst variables. The parameters of Stochastic Frontier Production Function estimated were positively consistent with the study's a priori expectation for such variables as fertiliser (0.2634), labour (0.3159), land (0.1846), and tractor (0. 1587). Output-oriented technical efficiency is 0.7802 (78%) and 22% is technically inefficient. A decreasing returns to scale value of (0.9226) with a scale effect of 0.9226. The sector is 58% economically efficient with cost savings of 42% and 75% allocative efficiency. This study concludes that Nigeria's agriculture suffers from production inefficiencies and this inefficiency can be reduced by using the same input levels. [ABSTRACT FROM AUTHOR]

The effects of technical change may not exclusively be labour-augmenting, if it is assumed that linear homogeneity or balanced growth is not applicable. This study identified these effects on the steady-state output growth from labour, capital and scale-augmenting technological progress. The findings imply that a drop in investment-goods prices accelerates output growth but to a lesser extent than capital growth, and increasing (decreasing) returns to scale (IRS/DRS) will lead to faster (slower) per-capita output growth, but the effect is free from constant returns to scale (CRS). It was also found that a higher output elasticity of capital can be beneficial to output growth and that a substantial labour supply is conducive to higher income per capita under IRS but will reduce it if DRS are present, but again, CRS does not occur. Differentiating between labour and capital augmentations in empirical research is challenging, as a direct estimation of the impacts of technical change on output growth is impossible. Thus, an indirect estimation was conducted to measure these impacts as a Solow residual. [ABSTRACT FROM AUTHOR]

The frequent occurrence of haze has caused widespread concern in China, and PM2.5 is thought to be the main cause. Previous research showed that PM2.5 was not only influenced by meteorological conditions but also by land cover especially surface vegetation. It was concluded that PM2.5 concentration is significantly influenced by surface vegetation, but spatially how and in what manner are still unanswered. Taking the central area of Nanchang City, China, as a case, this study firstly applied land use regression (LUR) model to simulate the distribution of PM2.5 in 2020. Then, the dichotomous model was used to determine vegetation coverage. A statistical regression model was used to analyze the influence of vegetation cover on PM2.5 and the scale effects. The results showed that (1) vegetation coverage and PM2.5 concentration were both significantly negatively correlated at the spatial scales selected for this study. (2) The effect of vegetation coverage on PM2.5 varied with season and the 500 m had the best correlation. (3) The non-linear regression model fits better than the linear model, and the effect of vegetation coverage on PM2.5 was complex. (4) The effect of vegetation coverage on PM2.5 concentration was different with PM2.5 concentration level. The higher the PM2.5 concentration, the more pronounced the effect of vegetation coverage on it. This study proposed the idea and method of coupling vegetation coverage with PM2.5 concentration at the regional scale from gradient landscape's point of view and provided some references for mitigating PM2.5 pollution through optimizing urban vegetation patterns. [ABSTRACT FROM AUTHOR]

Large scale agricultural business entities (hereinafter referred to as "the large scale entities") are newly sprouted in the process of China's agricultural transformation from traditional production to modern mode, while the improvement of agricultural total factor productivity is an important driving force to realize agricultural transformation in China. Therefore, it is of great significance to explore whether the former has a promoting effect on the latter. First of all, the effective improvement of agricultural total factor productivity by the large scale entity development is analyzed from the two aspects of scale effect and technology utilization effect, and the effect mechanism is discussed in depth in this paper. Secondly, empirical test was carried out by using the panel data of prefecturelevel cities from 2015 to 2020. The benchmark regression results show that the development of large scale entities can significantly improve agricultural total factor productivity. The mechanism test results indicate that the development of large scale entities improves the agricultural total factor productivity by raising the agricultural mechanization level. The results of heterogeneity analysis show that the difference between large scale entities would affect the benchmarking results. Therefore, it is believed through the study as discussed in this paper that devoting greater effort to support the development of large scale entities is an important measure to improve agricultural total factor productivity and promote China's agricultural transformation, but it is necessary to act according to local conditions based on the difference of entity types in the process. [ABSTRACT FROM AUTHOR]

Refractories play an important role in societies' progress as they enable extensively consumed materials to be processed such as steel and cement. Because of the high demand of these supplies, refractory-lined equipment comprises massive structures that have large dimensions and weighs several tons. Conversely, laboratory samples, used to study the behavior of these materials, are orders of magnitude smaller and often found weighing less than 1 kg. Within the context of refractory castable drying, this work aims to investigate the impact of size effects on water removal dynamics during thermogravimetry tests. The analysis of mass loss and its derivative with respect to temperature indicates that increasing the heating rate applied in the small samples can lead to a better reproduction of the evaporation and ebullition stages of the drying of large ones, due to the compensation effect of the faster temperature increase on the smaller sample sizes leading to similar thermal gradients. Furthermore, the presence of polymeric fibers and their influence on the size effect are also examined, showing that the increased permeability induced by such additives reduces the intensity of the scale effect. Additionally, it was found that for cubic samples with sizes equal to or larger than 10 cm, a kink in the temperature evolution measured at the center of the samples took place. A hypothesis based on the results and on observations of recent studies is proposed to explain this phenomenon, attributing it to the rapid evaporation of accumulated liquid water at those positions. This study also highlights the importance of considering the size-dependent nature of drying dynamics in refractory castables, as conventional thermogravimetry on laboratory scale samples may overlook important phenomena. Understanding the mechanisms occurring at real structural scales during water removal is crucial for predicting their behavior upon heating and enabling faster and safer drying processes for refractories. [ABSTRACT FROM AUTHOR]

Soundscape quality in green spaces of residential areas directly contributes to residents' quality of life. It has close relationships with landscape characteristics, which should be considered in landscape planning and design processes in residential areas. Accordingly, this study proposed a new perspective on the interrelationships between soundscape perception and landscape pattern on multi-scale, based on a case study of 30 residential green spaces in Fuzhou, China. Percentage of Landscape (PLAND), Patch Density (PD), Landscape Shape Index (LSI), and Patch cohesion index (COHESION) were utilized to represent the landscape pattern of vegetation, buildings, and roads in the residential areas. Soundscape perception was interpreted using the sound dominant degree (SDD) of sound sources and overall soundscape quality. The examined spatial scales range from 20 m to 180 m, with concentric circles spaced 20 m apart for each sampling point. Correlation analyses indicated that most landscape indices of vegetation and buildings were correlated with these soundscape perception indicators, while limited landscape indices of roads were associated with them. Based on the multi-scale landscape indices, multiple linear regression models for the SDD of sound sources and overall soundscape quality were established, confirming that the scale effect of landscape patterns can affect soundscape perception. Expressly, results indicated that these models were chiefly influenced by the landscape indices at a scale less than 120 m, but the scale effect of landscape pattern on the SDD of birdsong, pleasantness, and quietness was not so evident. Furthermore, we found that the number of explanatory variables may somewhat affect the model performance. The overall interpretability of these landscape indices for the SDD of sound sources was better than that of overall soundscape quality, implying the complexity of the latter. This study offers a fresh insight into the relationship between landscapes and soundscapes at varying scales. The findings can provide useful information for the promotion strategies of landscapes and soundscapes, especially in residential green spaces. [ABSTRACT FROM AUTHOR]

The monopile is the most common foundation to support offshore wind turbines. In the marine environment, local scour due to combined currents and waves is a significant issue that must be considered in the design of wind turbine foundations. In this paper, a full-scale numerical model was developed and validated based on field data from Rudong, China. The scour development around monopiles was investigated, and the effects of waves and the Reynolds number Re were analyzed. Several formulas for predicting the scour depth in the literature have been evaluated. It is found that waves can accelerate scour development even if the KC number is small (0.78a) is proposed and validated with field data. The equilibrium scour depth predicted using the proposed equation is evaluated and compared with those from nine equations in the literature. It is demonstrated that the values predicted from the proposed equation and from the S/M (Sheppard/Melville) equation are closer to the field data. [ABSTRACT FROM AUTHOR]

Rapid expansion of Spartina Alterniflora (S. alterniflora) has led to severe ecological consequences in coastal wetlands in China. Better understanding of the mechanism of S. alterniflora expansion is of great importance for its control and management. Although previous research has reported that the expansion of S. alterniflora is closely related to tidal creeks via field investigations, few studies have quantitatively investigated their relationships using remote sensing at different scales. In this study, we utilized time series satellite remote sensing imagery with different spatial resolutions to investigate the effects of tidal creeks on S. alterniflora expansion at both landscape scale and patch scale. We took the Yellow River Delta (YRD), China as our study area, where S. alterniflora has spread across the intertidal wetlands during the past decade. At landscape scale, we first derived the yearly maps of S. alterniflora and tidal creeks during 2009–2020 based on Landsat-series satellite imagery, then analyzed the spatio-temporal relationship between S. alterniflora and tidal creeks. By using grid analysis method, we evaluated the change of S. alterniflora area and tidal creek length and compared their change time. The results showed that 30.46 % of the grids experienced no change in tidal creeks while expansion of S. alterniflora, and 54.02 % of the grids experienced S. alterniflora area increase after the lengthening of tidal creeks. The results indicated that relationship between tidal creeks and S. alterniflora in YRD was dominated by “tidal creeks promoting S. alterniflora expansion”. We then simulated the S. alterniflora expansion at patch scale using an improved spatially explicit individual-based model based on S. alterniflora maps derived from Landsat imagery (30 m) and GF-1 high spatial resolution imagery (2 m), respectively. The results showed that consideration of long-distance dispersal of seeds along the direction of tidal creeks considerably enhanced the simulation accuracy, regardless of the spatial resolution of the S. alterniflora maps. High-resolution S. alterniflora maps yielded higher simulation accuracies. Our study suggests that the long-distance dispersal of seeds led by tidal creeks is an important manner for S. alterniflora expansion. Satellite remote sensing imagery have great potential to discover the mechanism of S. alterniflora expansion, facilitating control of S. alterniflora at the early invasion stage.

The demand for miniature, high-precision products is growing rapidly in many industries, which is driving the need for efficient manufacturing technologies. Micromilling is the most universal process for micromachining of metals and alloys. Therefore, the study of micromilling processes to increase the efficiency of machining miniature structural elements of products is an important issue for the current level of manufacturing technologies. The article presents an analytical review of modern scientific research on the process of micromilling of metals and alloys. The basic requirements for micromilling machines, their types and technical parameters are described. Typical micromilling designs, tool materials for their manufacture, and types of wear-resistant coatings used are discussed. The article provides manufacturers' recommendations on the purpose of micromilling conditions for various materials. The article explains the relationship between the effect of the minimum thickness of undeformed chips and the value of the kinematic rake angle and the scale effect with variations in cutting forces. The article discusses the peculiarities of chip formation during micromilling, namely the mechanism of chip removal at different thicknesses of the undeformed chips. The article highlights possible technical difficulties encountered during the cutting process and summarises recommendations for their solution and efficient micromilling of metals and alloys.

In this paper, the development of a 3D adaptive probabilistic explicit cracking model for concrete is reported. The contribution offered herein consists in a new adaptive mesh strategy designed to optimize the use of interface elements in probabilistic explicit cracking models. The proposed adaptive mesh procedure is markedly different from other strategies found in the literature, since it takes into account possible influences on the redistribution of stresses after cracking and can also be applied to purely deterministic cracking models. The process of obtaining the most appropriate adaptive mesh procedure involved the development and evaluation of three different adaptivity strategies. Two of these adaptivity strategies were shown to be inappropriate due to issues related to stress redistribution after cracking. The validation results demonstrate that the developed adaptive probabilistic model is capable of predicting the scale effect at a level similar to that experimentally observed, considering the tensile failure of plain concrete specimens. The results also show that different softening levels can be obtained. The proposed adaptive mesh strategy proved to be advantageous, being able to promote significant reductions in the simulation time in comparison with the classical strategy commonly used in probabilistic explicit cracking models.

Preventing eutrophication requires a deep understanding of nutrient sources and migration processes. The Guanshan River in the Danjiangkou Reservoir was selected as a typical agricultural basin. River water, sediment, and soil samples were collected to determine nitrogen (N) and phosphorus (P) contents and forms. Multivariate statistical analysis, buffer analysis, and extreme gradient boosting regression (XGBoost) were used to investigate the nutrient sources, the sources’ scale effects, and migration. The results showed that the exogenous sources of river nutrients were fertilizer (provided phosphate (PO4-P) and ammonium (NH4-N)), domestic wastewater (provided nitrate (NO3-N) and organic nitrogen), and natural soil and rock leaching (provided PO4-P and organic phosphorus). Fertilization within 300–1200 m and domestic wastewater discharge within 150 m of the river affected the contents of the river nutrients significantly (with R ranging between 0.40 and 0.73, p ≤ 0.01). The sediment was the N source and P sink of the overlying water. With NH4-N/PO4-P compound fertilization, the NO3-N and calcium-bound phosphorus (Ca-P) exhibited co-enrichment. Appropriately increasing NH4-N application could stimulate P biological uptake, thus inhibiting P emigration from agricultural soil under N-limited states. In conclusion, this study effectively recognized river nutrient sources and their scale impacts and also explored more effective fertilization strategies, which are beneficial for the optimized management of agricultural activities.

Thinning is a crucial approach to the near-natural conversion of plantations, contributing to the sustainability of forest management. However, over a rotation, the effects of thinning on tree growth, structure, and species diversity, as well as their scale-dependent outcomes, remain unclear. Ten years after conducting individual tree thinning in a Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) monoculture in southwest China, we analyzed the thinning effects within the influence zone (r = 0–2.5 m) centered around stumps and center trees. The results indicate that (1) individual tree thinning did not significantly promote the increment of diameter at breast height, volume, and biomass of Chinese fir. The four nearest Chinese fir around stumps and center trees were in a state of random distribution, high mixing, and dominance; (2) individual tree thinning significantly promoted the formation of species abundance and richness at r = 2–2.5 m. With increased scale, more species were found, leading to increased stability in diameter and species distribution. Linear and nonlinear relationships between diameter classes, mingling, and dominance became more stable; (3) later-coming populations within both modes exhibited a common characteristic of random distribution, high mixing, and disadvantage at each scale, but with significant differences in species composition (kj = 0.22–0.61). These results suggest that individual tree thinning has limited impacts on the growth and structure of retained trees in Chinese fir plantations but significantly enhances the formation of species diversity, demonstrating scale effects. This underscores the feasibility of individual tree thinning in the near-natural conversion of plantations.

Topographic scale characteristics contain valuable information for interpreting landform structures, which is crucial for understanding the spatial differentiation of landforms across large areas. However, the absence of parameters that specifically describe the topographic scale characteristics hinders the quantitative representation of regional topography from the perspective of spatial scales. In this study, false-color composite images were generated using normalized topographic relief data, showing a type of scale-oriented terrain pattern. Subsequent analysis indicated a direct correlation between the luminance of the patterns and the normalized topographic relief. Additionally, a linear correlation exists between the color of the patterns and the change rate in normalized topographic relief. Based on the analysis results, the issue of characterizing topographic scale effects was transformed into a problem of interpreting terrain patterns. The introduction of two parameters, flux and curl of topographic field, allowed for the interpretation of the terrain patterns. The assessment indicated that the calculated values of topographic field flux are equivalent to the luminance of the terrain patterns and the variations in the topographic field curl correspond with the spatial differentiation of colors in the terrain patterns. This study introduced a new approach to analyzing topographic scale characteristics, providing a pathway for quantitatively describing scale effects and automatically classifying landforms at a regional scale. Through exploratory analysis on artificially constructed simple DEMs and verification in four typical geomorphological regions of real terrain, it was shown that the terrain pattern method has better intuitiveness than the scale signature approach. It can reflect the scale characteristics of terrain in continuous space. Compared to the MTPCC image, the terrain parameters derived from the terrain pattern method further quantitatively describe the scale effects of the terrain.

The structure and diversity of plant communities respond to changes in landscape structure and vary with spatial scale, stand age and plant size. Therefore, it is important to identify the scale (grain size and extent) at which secondary forest attributes of large and/or small plants and landscape structure are more closely associated. We performed multi-scale analyses in which different grain sizes and extents were assessed to determine the most appropriate spatial scale for assessing the association of large/small tree aboveground biomass and species richness with successional age and landscape structure using regression analysis. AGB and species richness were more strongly associated with landscape structure when large grain sizes (500 m2) were used, with R2 values between 0.31 and 0.43. Variation in AGB and species richness was explained primarily by successional age and landscape structure, respectively. At large extents, successional age was related to the AGB of large trees (R2 = 0.43); at intermediate extents, landscape structure was related to the species richness of large trees (R2 = 0.31). The approach and results of this study may facilitate the identification of appropriate areas and scales for the maintenance or restoration of tree diversity, carbon storage, and the provision of ecosystem services in tropical dry forests.

The factors influencing the spatial evolution of rural settlements have always been the focus of rural geography. China's rural settlement space has undergone dramatic changes driven by rapid urbanization in recent decades. However, the spatial heterogeneity and scale effects of the factors influencing the spatial evolution of rural settlements have not attracted widespread attention and in-depth research from scholars. Taking Haikou City as a case example, this study examined the spatial heterogeneity of the factors influencing the spatial evolution of rural settlements from 2002 to 2020 using the remote sensing image visual interpretation method, spatial analysis technology of Geographic Information System (GIS), and Multi-scale Geographically Weighted Regression model. The study showed that: (1) The area of rural settlements in Haikou City has increased by 53.5% in the past 20 years, and the per capita area has grown from 120.59 square meters per person to 166.79 square meters per person, with the characteristics of expansion in the north and contraction in the south, a scattered settlement landscape, and obvious spatial heterogeneity. Moreover, the distribution and area changes of rural settlements showed a significant positive spatial agglomeration pattern. (2) The influences of various factors have obvious differences on spatial non-stationarity and scale effects with bandwidths ranging from 69 to 10 482. The effects of four factors, location, distance to road, distance to real estate development area, and elevation, on the spatial evolution of rural settlements are at the local scale. The effects of two factors, urbanization rate and slope, are at the mesoscale, and the effects of five factors, distance to the central city, population change rate, distance to river, road network density, and accessibility of tourist resource points, are at the global scale. Among these, the spatial evolution of rural settlements is most sensitive to location. (3) Factors such as the impetus of the central city and the development of real estate have the most important impact on the spatial evolution of rural settlements. In addition, settlements are increasingly expanding to areas closer to the central city, closer to real estate development zones, and closer to areas with lower altitudes, smaller slopes, higher levels of urbanization, and higher densities of road network. However, factors such as distance to river, population change rate, and accessibility of tourist resource points have no significant effects on the evolution of rural settlements. (4) Changing the development concepts led by the real estate industry and strictly implementing the "One household, one house" system are important measures to curb the disorderly expansion of rural settlements in Haikou City effectively.