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The potential of clean energy is constrained by various social, environmental, and technological challenges. The current work is likely the first to observe the influence of economic complexity on production-based carbon emissions to develop clean and sustainable energy solutions that address climate change apprehensions. The study examines the impacts of clean energy, economic complexity, public service transportation, and improving technology on production-based carbon emissions. This study employ the novel dynamic autoregressive distributive lag simulation method and a novel machine learning technique, Kernel-based regularized least squares, to ascertain the causal effect among variables. The results reveal that economic complexity is escalating environmental contamination. Similarly, public service transportation increases environmental costs, but clean energy and improving technology decrease the production-based emissions in China. These findings offer valuable guidance for China's public transportation system to integrate and consolidate the road, railway, airline transportation, and aviation sectors. [ABSTRACT FROM AUTHOR]

Resource-driven models and technology-driven models appear in different stages of economic development. In the early stage of industrialization, resource-driven economic development is usually the main development mode. Due to the impact of scientific progress and resource shortages, technology-driven economic growth has gradually become mainstream in the middle and late periods of industrialization. However, what are the differences between these two development models in driving economic growth? What is the asymptotic and iterative relationship between them? Understanding the interaction between the two is helpful to promote high-quality economic development. Therefore, by constructing a comprehensive evaluation framework of economic growth-resource consumption-technology progress and using the system dynamics model to simulate the evolution characteristics of the regional economic development driving force in the Yangtze River Economic Belt (YREB), the study finds that there is a long-term stable interaction between economic development and the resource- and technology-driven system in the YREB from 2015 to 2030. The energy of the simulation model is accurately reflects the regional development status, and the error of all simulation values is controlled within 5%. With the continuous improvement of economic aggregates, the contribution of technology input to economic growth gradually increases, while the driving force of resource input to economic growth shows a downward trend. Technological progress has become the most important driving force for sustainable economic development, especially the investment of technical personnel and technological capital. This study deepens the understanding of the driving mode of economic development and provides a reference for the development practice of other regions. [ABSTRACT FROM AUTHOR]

Shale oil in China is widely distributed and has enormous resource potential. The pores of shale are at the nanoscale, and traditional research methods encounter difficulty in accurately describing the fluid flow mechanism, which has become a bottleneck restricting the industrial development of shale oil in China. To clarify the distribution and migration laws of fluid microstructure in shale nanopores, we constructed a heterogeneous inorganic composite shale model and explored the fluid behavior in different regions of heterogeneous surfaces. The results revealed the adsorption capacity for alkanes in the quartz region was stronger than that in the illite region. When the aperture was small, solid–liquid interactions dominated; as the aperture increased, the bulk fluid achieved a more uniform and higher flow rate. Under conditions of small aperture/low temperature/low pressure gradient, the quartz region maintained a negative slip boundary. Illite was more hydrophilic than quartz; when the water content was low, water molecules formed a "liquid film" on the illite surface, and the oil flux percentages in the illite and quartz regions were 87% and 99%, respectively. At 50% water content, the adsorbed water in the illite region reached saturation, the quartz region remained unsaturated, and the difference in the oil flux percentage of the two regions decreased. At 70% water content, the adsorbed water in the two regions reached a fully saturated state, and a layered structure of "water–two-phase region–water" was formed in the heterogeneous nanopore. This study is of great significance for understanding the occurrence characteristics and flow mechanism of shale oil within inorganic nanopores. [ABSTRACT FROM AUTHOR]

The ecosystem service value (ESV) is an important basis for measuring an ecological environment's quality and the efficient management of ecosystems. It is particularly necessary to explore a proven methodology for assessing and predicting ESV dynamics coupled with policy-oriented scenarios that can provide a theoretical groundwork for macro decision, particularly in the context of implementing ecological protection and restoration projects. This study selected the land cover (LC) of Sichuan Province at five periods and the spatiotemporal dynamic equivalent factor method to assess the ESVs from 2000 to 2020. Additionally, the study coupled the Markov chain and GeoSOS-FLUS model, and predicted the future pattern of ESVs under four future development scenarios. The results show that (a) the areas of forests, shrubs, waters, wastelands, wetlands, and impervious areas showed a continuous increase from 2000 to 2020, with the most frequent interchanges occurring among croplands, forests, and grasslands. (b) The implementation of ecological protection and restoration projects led to a 13,083.32 × 108 yuan increase in ESV, and barycenter of the ESVs is located in the northeastern part of Ya'an and exhibits a tendency to move towards the northeast. (c) The ESV aggregation pattern of each city has remained unchanged, with Ganzi being the only city with a high aggregation. Overall, there are more conflict cities than coordination cities between economic development and the ecological environment. (d) The total ESV in 2025 will continue to increase under all development scenarios, reaching a maximum of 50,903.37 × 108 yuan under the EP scenario. This study can provide insights for ecological planning decisions and sustainable regional socio-economic development. [ABSTRACT FROM AUTHOR]

This study provides new insights into the impact of climate policy uncertainty, energy consumption, and economic development on China's carbon emissions. In doing so, we develop a novel index of China's climate policy uncertainty (CCPU). We then use the newly constructed dynamic autoregressive distributed lag (ARDL) simulation model, the frequency-domain causality (FDC) test, and the fully modified OLS (FMOLS) estimation to investigate these potential relationships from 2005 to 2021. The empirical results suggest that increasing CCPU reduces carbon emissions in most parts of China, which improves environmental degradation. Furthermore, the effects of energy consumption and economic growth on carbon emissions are confirmed to be positive in each location. Finally, the results of the FDC and FMOLS confirm the robustness of the model. Our findings suggest that information from the CCPU can be used to forecast CO2 emissions in China. Furthermore, the government should strike a balance between economic growth and environmental regulation and promote the use of renewable energy to reduce carbon emissions. Proactively developing climate policy is important to achieve the goal of carbon neutrality. [ABSTRACT FROM AUTHOR]

The Xiaomojiu landslide is a typical high-elevation, long-runout landslide located in the Jinsha River Corridor. In this study, sequential InSAR time-series estimation was used to calculate the line of sight (LOS) surface displacements with descending and ascending Sentinel-1 images, and it turned out that the cumulative LOS surface displacement of the landslide was up to −78.4 mm during the period from October 2017 to April 2021 with the maximum LOS surface displacement rate of −38.5 mm/year. The landslide body could be divided into five zones (A, B1, B2, B3, and C) according to its topographical characteristics together with the LOS surface displacement time series. Combining engineering geological characteristics, LOS cumulative surface displacements with site investigation suggest that the Xiaomojiu landslide is likely to be a precipitation-triggered ancient traction rock landslide at the accelerated deformation stage. A dynamic simulation of the Xiaomojiu landslide with the PFC3D software shows that it could take approximately 65 s for the Xiaomojiu landslide from start-up to acceleration to deceleration to build-up of a barrier lake, followed by a simulation from the barrier lake to outburst floods with the HEC-RAS software indicating that the maximum depth of the outburst floods could be 13.5 m (15%), 24.6 m (25%), 42.1 m (50%), and 50.3 m (75%) along Qinghai-Tibet Plateau Transportation Corridor (QTPTC). It is believed that the results of this study provide a reference for landslide prevention along the QTPTC and the Jinsha River. [ABSTRACT FROM AUTHOR]

By solving the problems such as the shortage of drainage power in inland rivers and the difficulty of construction land, the integrated gate pump with compact structure and small floor area has received much attention. Among them, the integrated gate pump with larger diameter has a short application time and few examples in China. This paper takes the Salt River Pump Gate Project as the background, uses the three-dimensional parametric calculation model, carries on the design optimization analysis of the door blade thickness, the plate thickness and other parameters, and the reinforcement analysis of the weak parts of the wall pipe and web. At the same time, the key problems such as vibration and anticorrosion of the gate pump are analyzed and demonstrated. The results show that the thickness of the door blade should not increase too much, and the panel and web structure with large separation should be properly strengthened at the same time to control the resonance frequency domain. When the ratio of gate width to height is less than 0.6 and the ratio of the pump outer diameter to gate width is close to 0.5, the plate thickness combination in the range of 12-16 mm should be used. Transverse, longitudinal and diagonal ribs should be considered at the same time for wall pipe reinforcement. Through a dynamic simulation analysis, the design of Salt River Pump Gate can avoid the resonance of the integrated pump gate, and has a certain safety margin. [ABSTRACT FROM AUTHOR]

Global climate continues to warm; by reducing carbon emission (CE) to cope with climate warming has become a global consensus. The influencing factors of CE exhibit diversification and spatial characteristics, and the complexity of the CE system poses challenges to green and low-carbon development and the realization of China's dual-carbon goals. Taking the Pearl River Delta urban agglomeration as an example, this study explored the influencing factors of CE and designed emission reduction schemes with the help of multi-scale geographically weighted regression (MGWR). Based on this, the system dynamics model was used to construct a CE system framework considering multi-dimensional driving factors, so as to combine the complex CE system with the emission reduction countermeasures considering spatial heterogeneity, and realize the dynamic simulation of CE reduction policies. The results showed that the urban agglomeration as a whole will reach carbon peak by 2025. Shenzhen, Zhuhai, and Dongguan have achieved carbon peak before 2020, while other cities will reach carbon peak by 2025–2030. The government policy constraints can effectively curb CE, but if government constraints were relaxed, CE will rise and individual cities will not reach carbon peak. Comprehensive CE reduction policies are better than a single CE reduction policy. The study found that this model framework provides a systematic analysis of carbon reduction strategies for urban agglomerations, offering decision-makers various combinations of economic development and green low-carbon objectives. This will further contribute to a multi-faceted mitigation of high emission in urban agglomeration and promote regional sustainable development. [ABSTRACT FROM AUTHOR]

The supply capacity of water resources, food and meat products is of great importance to the people's livelihood of a country. In recent years, although China has introduced many policies on water resources and grain production, the current situation of China's food self-sufficiency and imbalance between supply and demand of water resources has not been fundamentally changed. Food security and water security are facing a serious situation. This paper takes the water footprint as the connection point, and combines the water food meat system with mutual influence, mutual causation and dynamic feedback into a composite system. At the same time, the simulation model of the composite system is established by using system dynamics, and the dynamic simulation of water grain meat in China from 2000 to 2050 is carried out to explore the current situation and future development trend of China's water, grain and meat supply capacity. It was found that during the simulated period, the agricultural blue-green water footprint on the demand side would continue to dominate, followed by the gray water footprint. The blue water footprint on the supply side remained stable, whereas the green water footprint and the circulating water footprint showed an upward trend. According to the contemporary social and economic development and the model of water resources in China, there will be no meat shortage in the future, but issues have been found in the ability to guarantee water and food supply. The root of China's food support capability problem is excessive grain consumption due to meat production, whereas the cause of the water support capability problem is the slow development of the water conservation. Food support capability issues can be solved by regulating the meat output of livestock farming and fishery operations, reducing excess production capacity, and stabilizing the meat supply and demand. To solve the water support capability issue, China should focus on accelerating the pace of agricultural water-conservation development, improving the sewage treatment system, building rainwater-collection projects, and promoting the research and development of water recycling technology. This study provides support for optimizing the structures of the meat and grain industries and the policy formulation of the efficient use of water resources in China. [ABSTRACT FROM AUTHOR]

For simulating the dynamic rupture process in earthquake scenarios, the stress distribution along the fault remains unclear owing to a lack of direct measurements. Regional stress fields are often resolved onto the fault plane to determine the stress distribution along it. To overcome this limitation, we considered different interseismic locking models to better constrain the actual stress distribution. Specifically, we took the Suoerkuli section in the middle of the Altyn Tagh fault, China, and conducted dynamic rupture simulations to obtain possible earthquake scenarios. The surface rupture length and moment magnitude obtained from the simulations were consistent with those of historical earthquakes. Compared with the traditional stress field resolution method, our approach led to better constrained fault rupture extent and distribution characteristics of regional intensity, thereby avoiding overestimations of earthquake damage. We conclude that examining regional seismic hazards and risks based on seismic dynamic rupture simulations that account for the locking ratio of the fault plane is advantageous, and should be encouraged. [ABSTRACT FROM AUTHOR]

During the past two decades, more and more rail-cum-road bridges have been built to meet the ever-increasing demand of highway and railway transportation in China. The rail-cum-road bridges are expected to withstand multiple types of loadings during normal operation, including wind, road vehicle, and train. Accurate quantifications of the coupling dynamics among bridge, road vehicle, and train are essential to ensure the safety and reliability of rail-cum-road bridges during their lifetime. The present study develops an analytical framework to simulate the complex wind–road vehicle–train–bridge (WRVTB) system. In addition, a scalable multiple-time-step (SMTS) algorithm is proposed to overcome the computational efficiency issue of traditional single-time-step (STS) algorithms for solving the WRVTB interaction. The SMTS algorithm utilizes domain decomposition techniques to enable a fine and a coarse time-step to be assigned for a road vehicle–train subsystem and bridge subsystem, which greatly improves the computational efficiency for solving the WRVTB interaction. A numerical simulation of coupled WRVTB analysis is conducted based on a prototype rail-cum-road bridge to demonstrate the computational efficiency and accuracy of the proposed method. The results indicate that both the MTS and the SMTS algorithms are able to achieve better accuracy and efficiency simultaneously in comparison with the STS algorithm. Although the SMTS algorithm does not exhibit obvious superiority over the MTS algorithm in terms of the overall accuracy and computational efficiency, the major advantage of the proposed SMTS algorithm over the MTS algorithm is the flexibility. When the SMTS algorithm is adopted, a refined time-step can be assigned to a subsystem of interest, while relatively coarse time-steps can be assigned to the remaining subsystems. As such, the desired accuracy of the subsystem of interest is guaranteed at a low computational cost. [ABSTRACT FROM AUTHOR]

Analysing the dynamics of landscape connectivity is of great significance for biodiversity conservation, but the scientific expression of ecological processes and the depth of coupling landscape pattern and ecological process requires to be strengthened. Taking the grassland of Poyang Lake as a case, based on the integrated perspective of habitat and biology, and comprehensively considering the ecological process of water level change and species dispersal, this study firstly analysed the changes of functional connectivity of grassland with different water levels and dispersal distances by using the graph‐based connectivity indices. Then, landscape pattern indices were applied to analyse the dynamics of landscape pattern of grassland and further study the effects of landscape pattern on landscape functional connectivity. The results showed as follows: (1) From the perspective of habitat, the functional connectivity of grassland has progressively decreased with the increase of water level. From the perspective of ecology, the species dispersal distance had an absolutely positive impact on landscape functional connectivity. With the increase of dispersal distance, the functional connectivity of grassland increased significantly. (2) The dynamics of landscape pattern of grassland showed that with the increase of water level, the patch area shrank, the patch shape tended to be simple, the patch density decreased and the patch fragmentation aggravated. (3) The correlation results between landscape pattern and functional connectivity indicated that flux index (F) had a significant positive relationship with patch density (PD), edge density (ED), probability of connectivity (PC) had a strong significant positive relationship with largest patch index (LPI), COHESION and number of components (NC) had a negative relationship with LPI, ED, COHESION. This study provides theoretical guidance for the protection and management of grassland in Poyang Lake. [ABSTRACT FROM AUTHOR]

Given a new perspective on the environmental hypothesis, this paper systematically investigates the validity of the environmental Kuznets curve (EKC), pollution haven, and pollution halo hypotheses using carbon efficiency as the dependent variable. Applying the dynamic autoregressive distributed lag simulations based on the annual time series data over the period 1990–2019, the study found that real GDP per capita has negative effects on China's environmental quality both in the short and long run, whereas the square of real GDP per capita has positive impacts. This validates the EKC hypothesis for China. Furthermore, foreign direct investment has negative effects on environmental quality in China, implying that the case of China exemplifies the pollution haven hypothesis and not the pollution halo hypothesis. The empirical results also demonstrate that energy efficiency and trade openness improve China's environmental quality both in the short run and long run. These findings, therefore, provide insights into achieving the ambitious climate goals in China by 2050. [ABSTRACT FROM AUTHOR]

Loess landslides pose significant physical and environmental threats to communities of the Heifangtai Terrace in Gansu Province, China. Estimating potentially affected areas using dynamic numerical simulations provides a foundation for risk assessment and management. However, current studies often use rheological input parameters derived from the back analysis of an individual historical landslide, which requires that the potential landslide is quite similar to the historical landslide to guarantee the accuracy of predictions. We collected data from 20 loess flowslides that occurred from 2015 to 2019 in the Heifangtai Terrace. A friction model embedded in MassFlow was used to simulate run-out behavior. Accumulation depths at multiple control points were used as observation information. A multi-objective optimization back analysis was used to calibrate optimal rheological parameters for each flowslide, yielding a region-specific database of 20 datasets for statistical analyses. Finally, two flowslides that occurred in 2019 were employed as potential landslides to conduct probabilistic run-out predictions based on the database. These predictions agreed well with the observed accumulation areas in both cases, thus validating our method. This database will be useful for future landslide run-out predictions in this area. [ABSTRACT FROM AUTHOR]

We simulated the rupture dynamics and ground motion of the 1850 Xichang, China, earthquake on the Zemuhe fault, which consists of the Lijinbao segment, the Dajing segment, the Chechejie segment, and the Songxin segment, with the curved grid finite‐difference method, and compared the simulation results with the field observed data and written records inferred data. We focused on the rupture extent of this earthquake and the effects of the maximum principal stress azimuth and nucleation location on the rupture process and the corresponding damage distribution. Numerical simulation results suggest that the regional maximum principal stress orientation that surrounds the Zemuhe fault was approximately N55°W, which is identical with the azimuth from the stress relief experiment in the neighboring area. Our simulations further imply that the nucleation location is under Lanbiluo. The simulation of this preferred nucleation location model suggests that the rupture propagated through the entire Dajing segment and the Chechejie segment, and the rupture gradually arrested at shallow depths after it transferred to the Lijinbao segment and the Songxin segment. Moreover, the simulation suggests that the rupture on the Chechejie segment was initiated at the surface and then mainly propagated downward due to the free surface effect. In addition, the Xichang earthquake may have exhibited a low rupture velocity on the Dajing segment. Furthermore, our simulation results emphasize the importance of the stepover width in the earthquake dynamics. Plain Language Summary: The 1850 Xichang earthquake occurred on the nonplanar Zemuhe fault. We used physics‐based computer simulations of the rupture process to investigate the rupture length and source location of this earthquake. We found that the regional stress direction and magnitude are important to the simulation results. We also found that this earthquake mainly propagates through two segments of the Zemuhe fault (five segments in total) and the source location is approximately under Lanbiluo at a depth of 10 km. Moreover, our simulation implies that the earthquake rupture directivity has a strong effect on the surface damage distribution of the research area. Key Points: We simulate the dynamic rupture and ground motion of the 1850 Xichang, China, earthquakeThe earthquake rupture area covers the entire Dajing and Chechejie segments, and part of the Lijinbao and Songxin segmentsNucleation location, stepover width, and free surface play important roles in the dynamic rupture process and slip distribution [ABSTRACT FROM AUTHOR]

The accurate simulation of the dynamics of the anaerobic–anoxic–oxic (A2O) process in the biochemical reactions in wastewater treatment plants (WWTPs) is important for system prediction and optimization. Previous studies have used real-time monitoring data of WWTPs to develop data-driven predictive models, but these models cannot be used to provide mathematical analysis of A2O dynamic properties. In this study, we developed a new simulation and analysis method for determining A2O dynamics in biochemical reactions using deep learning and the Koopman operator to address the above problems. This method was validated through data from a real-world WWTP in east China and compared it with the traditional deep learning model. According to the results, the new method achieved high-accuracy prediction. Meanwhile, with the help of the Koopman operator, the new method was able to analyze the asymptotical stability and convergence behavior of the A2O process, which provides a brand-new perspective for the in-depth study of biochemical reactor dynamics. [ABSTRACT FROM AUTHOR]

A simulation model based on Dymola modelling was developed to investigate the dynamic characteristics of automatic generation control (AGC) for variable-load thermal power units in this study. Specifically, a 300 MW unit from a power plant in northern China was used to verify the model's validity in steady-state processes and to analyze the behavior of the main thermal parameters under different rates of load changes. The economic performance of the unit under different rates of load changes is also analyzed by combining the economic indexes of "two regulations" in the power grid. Results indicate that as the rate of load changes increases, boiler output, main steam temperature, reheat steam temperature, main steam pressure, and working temperatures of various equipment fluctuate more intensely. Specifically, at a rate of load reduction of 2.0% Pe MW/min, the maximum deviation of the main steam temperature can reach 7.6 °C, with the screen-type superheater experiencing the largest heat exchange. To achieve a balance between safety and economics for the unit, the rate of load raising should not exceed 1.2% Pe MW/min, and the rate of load reduction should not exceed 0.8% Pe MW/min. This paper applies the covariance index and AGC assessment index of the thermal power unit load control system to the established dynamic simulation model to supplement the AGC assessment index in the "two regulations", and to provide a flexible and reasonable system evaluation result for field operators to refer to, so as to improve the economics of the system on the basis of safety. [ABSTRACT FROM AUTHOR]

The construction of island airports on coral reefs inevitably encounters the impact load of aircraft takeoff and landing. However, previous studies have not presented a detailed description of the dynamic response of the coral sand beneath the runways of island reclamation airports under aircraft load. In the current study, the coral sand of Mischief Reef Airport in the Nansha Islands, China, was selected as the background. The pore water pressure and strain characteristics of reshaped coral sand under aircraft loads with different dynamic stress amplitudes and vibration frequencies were studied using dynamic triaxial tests. Particle discrete element software was employed to study the deformation characteristics of coral sand with different particle sizes and porosities under aircraft loads. Results show that when the dynamic stress amplitude and vibration frequency were small, the pore water pressure and strain of the coral sand samples gradually increased with the number of load cycles, and the growth rate became increasingly small. When the dynamic stress amplitude and vibration frequency were large, the axial strain of the coral sand samples increased with the vibration frequency, and the growth rate exhibited an increasing trend. The deformation of the coral sand samples increased with porosity under aircraft loading. The larger the variation range of the coral sand particle size was, the larger the coral sand deformation caused by aircraft takeoff and landing load was. These results can provide a reference for the treatment and repair of the airstrip foundation of island airports. [ABSTRACT FROM AUTHOR]

This study investigates the performance of the 23 CMIP6 models in simulating spring precipitation over China and preliminarily explores the reasons for the underestimation of spring precipitation over South China (SC). The results show that the CMIP6 models can generally capture spring precipitation over China but have distinct underestimations in SC. In addition to analysing the results of the multimodel ensemble mean (MME), based on the regional mean spring precipitation differences over SC, we also analyse five models with greater overestimated precipitation amounts composing the high‐value MME (H_MME) and five models with greater underestimated precipitation amounts composing the low‐value MME (L_MME) as comparisons. Moisture budget analysis reveals that the underestimated dynamic component of vertical moisture advection mainly causes the negative biases of spring precipitation over SC. Further analyses indicate that the underestimation of the intensity of the East Asian subtropical jet (EASJ) generally causes weakened secondary meridional circulation to the south of 30°N and moisture convergence over SC in CMIP6 models. Consequently, less moistened air would be lifted to high levels, providing an unfavourable background for the occurrence of spring precipitation and inducing underestimation compared with the observations. The modelling EASJ shows much stronger (weaker) H_MME (L_MME), which generally enhances (weakens) the dynamic component of the secondary circulation over SC, favourable for the increase (decrease) in spring precipitation. [ABSTRACT FROM AUTHOR]

Terrestrial ecosystems play an important role in carbon reduction and sequestration, and it is important to explore the carbon sequestration potential of terrestrial ecosystems under different land use scenarios to enhance the regional carbon storage potential. We analysed land use changes in the Loess Plateau, an important ecological barrier in China, from 2000 to 2020, used the PLUS model to predict land use patterns under different scenarios in 2035, and applied the InVEST model to assess carbon storage from 2000 to 2035. The findings were as follows: (1) Cropland in the study area decreased significantly from 2000 to 2020, and forests, waters, and construction land showed an increasing trend. The area of cropland further decreased under the natural growth and ecological protection scenarios, the area of grassland decreased significantly under the cropland protection scenario, and forests and waters were effectively protected under the natural development, ecological protection, and cropland protection scenarios. (2) Carbon storage in the Loess Plateau has increased by 28 Tg (0.56%) over the past 20 years. Compared with those in 2020, by 2035, carbon storage under the natural development, ecological protection, and cropland protection scenarios will increase by 30, 44, and 21 Tg, respectively. (3) Carbon storage has obvious spatial heterogeneity, with high carbon density in the northern Qinling Mountains, Taihang Mountains, and Lvliang Mountains and low carbon density in Erdos City and its surrounding areas. Regional differences in carbon density are closely related to the spatial distribution of land use types. (4) Carbon storage showed an inverted V-shaped trend with the increase in elevation. Land use change is the main reason for the increase or decrease in carbon storage under different scenarios. Compared with the other two scenarios, the ecological protection scenario not only protects the ecological environment but also has a strong carbon storage potential, which may be significant for guiding the formulation of future land use planning on the Loess Plateau. [ABSTRACT FROM AUTHOR]

To achieve low-carbon development of industrial land in China, it is important to coordinate the conflicts of interest among stakeholders in the process of land expropriation and utilization. However, the complex interaction mechanism and influencing factors among stakeholders make it difficult to achieve the goal under the Chinese decentralization and unique land development pattern. To solve these problems, this paper first analyzes the four main stakeholders' conflicts of interest in the process of land expropriation and utilization, that is, the central government, local government, peasant, and enterprise. Then, we construct two evolutionary game models to examine the dynamic changes of stakeholders' different strategies and take the Beijing-Tianjin-Hebei region as an example to compare the impacts of factors on strategies under different conditions using simulation analysis. The research shows that under the Chinese decentralization, adjusting the action strengths of different stakeholders can have different effects on system equilibrium. In terms of the central government's reward and penalty, increasing the reward and penalty for local government will shorten the time of system equilibrium to a different degree, and there is little difference between the effects of political and economic penalties. Interestingly, increasing the incentives for peasants cannot promote the system equilibrium in advance. In addition, the key to local governments' decision on illegal land expropriation lies in benefits rather than costs, and investment in low-carbon technology reform with positive externalities is easier to control than investment in economic production with negative externalities associated with pollution emissions. [ABSTRACT FROM AUTHOR]

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To achieve the goal of clean heating in northern rural areas, a cooperative heating system, composed of a biomass boiler and a multi-source heat pump was proposed, based on building heat load and resource conditions. This cooperative heating system combined biomass energy, geothermal energy and air energy. A dynamic simulation model is established by using the TRNSYS software. Under the condition of energy balance, an optimization model is proposed based on the minimum annual cost. The proposed model is applied in a demonstration project for the Miaofuan rural community in Linzi Town, Linyi County, Dezhou City in Shandong Province, China. The heat supply ratio of each equipment and the operation mode of the coupled system are optimized. Results show that the coupled system with the optimal configuration can reduce the annual cost by 9.60%, 14.22% and 11.66%, respectively; compared with the geothermal heat pump, air source heat pump and biomass boiler alone. Therefore, the proposed cooperative heating system can be well applied in rural areas. [ABSTRACT FROM AUTHOR]

The comprehensive indexes approach based on stand structure parameters is mainly used to select trees for harvest. However, these indexes do not consider the comprehensive impact of horizontal and vertical structures, leading to an incomplete analysis of the forest structure and an inaccurate selection of trees for harvest. To solve this problem, we constructed a comprehensive decision index of logging (CDIL), integrating horizontal and vertical structure parameters which can identify harvest trees more scientifically. In this study, we took the Shanxia Forest Farm in the Jiangxi Province of China as the experimental area and used mixed broadleaf/conifer forests at different ages as our experimental sample. We selected eight horizontal and vertical spatial structure parameters to establish an efficient, objective, and accurate comprehensive decision index of logging. We combined 3D visualization technology to realize the dynamic visualization simulation of the index at different intensities of tending and felling management. The results indicated that the proposed CDIL-index could effectively optimize the forest spatial structure. From the perspective of stand structure adjustment, the optimal thinning intensity was 20%. The average CDIL in each plot decreased by more than 80% after logging, while the change range of each plot was between 30% and 70% after the F index was applied to implement tending and logging. The CDIL was 11.4% more accurate in selecting trees for harvesting than the F index. In this study, the main conclusion is that the CDIL would enable forest managers to more accurately choose trees for harvesting, leading to forest adjustment that would reduce the competition pressure among trees and improve the distribution and health of trees, possibly making the forest structure more stable. [ABSTRACT FROM AUTHOR]

The spring finger collection mechanism is a core component of balers. It is usually used to collect soft straw crops (corn straw, wheat straw, green forage), and rarely used for hard stem crops (such as branch pruning residues). Due to different biophysical characteristics of hard stem crops and soft straw crops, the collection mechanisms are also different. In China, branch pruning residues in apple orchards are collected manually. It is a heavy labor task. To this end, this article uses an improved spring finger mechanism to collect pruning residues in apple orchard branches, effectively replacing manual collection operations. A dynamic motion trajectory simulation platform is developed by analyzing each action using pitchforks or other agricultural tools throughout the entire collection process, and combined with the structure of the spring finger collection mechanism. The platform of the spring finger collection mechanism is improved to collect orchard branches, and redesign and manufacture the core components of the collection mechanism. In addition, comparative tests were performed on4 different placement orientation sunder the conditions of R=40±2 r/min and V=0.9-1.1 m/s. That is, 1) messy, 2) transverse, 3) portrait orientation (the treetop firstly contacts the collection device), and 4) portrait orientation (the thick stems of the branches first touch the collection device). The results indicate that 1) and 2) have similar success rates in picking branches, while 3) and 4) have lower success rates, especially with 4) being the lowest). The analysis found that some branches were directly inserted into the spring finger gap and moved under the machine, resulting in a large amount of losses. This study aims to improve the success rate of picking branches in the bundling machine and verify the relationship between different placement directions and the success rate of picking branches. [ABSTRACT FROM AUTHOR]

Emergency materials transportation, both economic and societal, is one of the most important parts of unconventional emergency management. In the present study, we built a quantitative simulation model underlying the mechanism of emergency materials transportation specifically regarding typhoon disasters. We then explored the internal influence factors and association mechanisms of the dynamic model as they relate to the effective control and guidance of emergency materials transportation. Using system dynamic model, this paper conducts the simulation study to identify the key influencing factors for the speed of emergency materials transportation. The relationships between influencing factors and the emergency capability were analyzed qualitatively. On this basis, SD flow chart was built. A typhoon disaster event in Leizhou Peninsula, China, is used as an example to validate the effectiveness and feasibility of the proposed model, as well as to simulate different emergency management strategies. Results of governmental emergency materials transportation are key factors in process of emergency formulating the policy to improve the speed and efficiency for emergency materials transportation during the emergency management process. [ABSTRACT FROM AUTHOR]

In this study, Weather Research and Forecasting (WRF) ‐based dynamic downscaling simulation was performed over China at a horizontal resolution of 25 km. To reduce the systematic large‐scale biases from lateral boundary conditions, a dynamic blending (DB) technique was introduced in downscaling, and its performance was compared with downscaling without DB (NO_DB) as well as the driving global climate model (GCM, i.e., HadGEM3). In the present‐day simulation for verification, added values were found in DB, relative to the GCM and NO_DB, in simulating the precipitation extremes, especially over southeastern China. Possible causes responsible for this improvement were further analyzed. In the GCM, excessive moisture and atmospheric heating in the upper troposphere in conjunction with abnormally strong deep convection resulted in excessive extreme precipitation over southeastern China, while in NO_DB, insufficient moisture and atmospheric heating in the whole troposphere in conjunction with abnormally weak convection suppressed extreme precipitation there. In comparison, DB showed a closer representation of observations in terms of vertical velocity and vertical profiles of atmospheric moisture and heating, accounting for the improved simulation of extreme precipitation. In the future projection under the SSP5‐8.5 scenario, both the GCM and DB predicted that extreme precipitation would increase in most parts of China; however, DB indicated a larger increase over southeastern China relative to the GCM. Stronger moisture flux convergence over southeastern China in DB accounted for this larger increase, and in addition, the thermodynamic effect associated with more precipitable water dominated the stronger moisture flux convergence. Key Points: High‐resolution climate simulation over ChinaDynamic downscaling with dynamic blending technology adds great value to the simulated extreme precipitationProjections of future extreme precipitation changes in China under the SSP5‐8.5 scenario [ABSTRACT FROM AUTHOR]

Under the current rapid urbanization and industrialization in China, competition for production, living, and ecological spaces is becoming fierce. Improving production–living–ecological spaces (PLESs) has become a core issue in China's land‐space development strategy. In this study, the multiple linear logistic regression (MLLR)–multicriteria evaluation (MCE)–cellular automata (CA)–Markov hybrid model was used to predict the land‐use pattern for 2030, and the spatial conflict model was established based on landscape indices to measure the evolution characteristics of spatial conflicts. The results demonstrated that, from 2005 to 2030, the production–ecological space (PES) will have front‐runner status in Wuhan, followed by the ecological–production space (EPS). In 2005–2015, the living–production space (LPS) and PES occupied large amounts of EPS and ecological space (ES), especially in the main urban areas and near rivers, and the spatial transformation was the most significant. By 2030, there will be less transformation of each space type, but the conversion amount of LPS will still be relatively large. With the passage of time, the LPS will increase, the EPS will decrease slightly, and the ES will fluctuate. During the period 2005–2030, the conflict level will change gradually from seriously out of control to controllable, and the hot spot of PLES will show a scattering distribution. The cold spot area will be distributed mainly in the southern part of Wuhan, which will be expanded greatly by 2030. Our research indicates that analyzing the reasonable utilization of PLES is of great value by identifying spatial conflicts; differentiated sustainable development strategies should be formulated according to the future spatial and temporal patterns of PLES, which can help in scientific judgments on the spatial matching of land use and provide early warnings of spatial conflicts. Integr Environ Assess Manag 2022;18:1578–1596. © 2021 SETAC KEY POINTS: The exchange of production–living–ecological spaces can present the contradictory signals of regional spatial conflict.The results of conflict identification of PLES in time and space can provide a reference for future regional specific optimizing land allocation.The measurement model constructed based on the landscape pattern indices can reveal the identification of regional spatial conflicts. Over time, the PLES spatial conflict in Wuhan will be gradually improved. [ABSTRACT FROM AUTHOR]

The variability and inhomogeneity of solar energy limits the development of solar heating systems (SHS) in many fields. In order to improve the utilization efficiency of SHS, this paper takes three typical cities (Xi'an, Dunhuang, Lhasa) as the research object, studies the operation state of SHS in student dormitory buildings, and puts forward a corresponding optimization strategy. The research shows that the reduction of water supply temperature will improve the operation efficiency and energy saving effect of a spontaneous combustion heat pump and that there is an optimal volume of heat storage water tank (HSWT), which can make the energy saving effect of SHS run better. The optimization of the SHS shows the water supply temperature is 35 °C, and the optimal volume of HSWT is 15 m3 in the "Resource-general area (Ⅲ)" represented by Xi'an, 25 m3 in the "Resource-rich area (Ⅱ)" represented by Dunhuang, and 40 m3 in the "Resource-richer area (Ⅰ)" represented by Lhasa. With the increase in the abundance of solar energy resources in the region, the optimal volume of HSWT also increases. Meanwhile, the solar energy contribution rate of the three regions in descending order is 61.3% (Lhasa), 32.8% (Dunhuang), and 25.9% (Xi'an). After optimization, the contribution of SHS increased by about 5%. The research results will help improve the efficiency of SHS in cold areas of China and make the system more efficient and energy efficient during operation. [ABSTRACT FROM AUTHOR]

Planetary rovers may traverse terrains with complex geometries and variable physical properties, but their mobility behaviors are complicated and difficult to simulate precisely. This article focuses on high-fidelity dynamic modeling and simulation for a type of rovers that incorporate single-input-multi-output joints to enhance terrain adaptability, which has been used on China's Tianwen-1 Mars rover. A novel multibody dynamic model and its solutions are derived first with consideration of single-input-multi-output joints. Then, a unified terramechanics model is proposed, considering variable terrain surfaces and covering rover's motion states of skidding, slipping, and steering, solved the problem of simulation instability caused by model switching between soft and hard terrains. As the contact areas of wheels with various terrains and resultant sinkage are dominant factors to ensure fidelity but difficult to determine, a new terrain modeling method for calculating contact area and wheel sinkage is developed using digital elevation map with physical properties. A simulation system is developed, integrating all the above models, and verified with physical experiments and commercial software. The relative simulation errors that have been achieved are less than 5.9% for bogie angles, 6.1% for drawbar pull, and 3.4% for slip ratios, demonstrating high fidelity simulation results. [ABSTRACT FROM AUTHOR]

As the basic unit of a city, community is an important carrier of residents' healthy life. With the development of society, the environmental status of old communities has been unable to meet the needs of residents' healthy life, and it is urgent to optimize the community environment. The emergence of novel coronavirus also put forward more strict requirements for the grassroots governance of old communities in China. Taking Fuguoli community in Beijing City as an example, the problems existing in the external environment of old communities were excavated from the perspective of functional requirements, and the distributed green space layout pattern and the dynamic simulation of community microclimate environment was constructed through the method of field survey and numerical simulation. Furthermore, the environmental optimization strategies of old communities with combination of peacetime and epidemic situation were put forward to help the epidemic prevention and control. [ABSTRACT FROM AUTHOR]

• Innovates wheel polygonal wear (WPW) diagnosis with calibrated wheel-rail FRF. • Cepstral-Bayesian FRF calibration using hybrid numerical-experimental data. • Weighted angle-synchronous moving average (WASMA) filter out rail disturbance. • FRF and WASMA synergy enhances accuracy for WPW quantitative diagnosis. The safety and efficiency of high-speed trains in China are significantly impacted by Wheel Polygonal Wear (WPW). Onboard monitoring methods for WPW currently suffer from reduced precision due to the intrinsic modal characteristics of the wheel-rail system and external disturbances such as rail roughness. To address this issue, this study develops a quantitative diagnostic approach for WPW employing a calibrated Frequency Response Function (FRF). A novel Cepstral-Bayesian calibration method is proposed for calibrating the FRF to precisely represent the real behaviors of the wheel-rail system, which is critical for considering system resonances. This method integrates information from dynamic simulation with sensor measurements. Furthermore, the weighted angle-synchronous moving average preprocessing is combined to reduce disturbances from rail roughness. Both dynamic simulations and field test data validate this technique, demonstrating its superior accuracy in quantifying WPW compared to existing methodologies. This offers a robust solution for both identifying and precisely quantifying WPW. [ABSTRACT FROM AUTHOR]

• Habitat quality was assessed for both historical and future scenarios for the Hexi region. • Quantitatively evaluate the contribution of land use transformation to habitat quality change in different scenarios from 2020 to 2030. • The spatial distribution of habitat quality was analyzed under the natural development and ecological protection scenarios. • Selection of typical cases in arid zones to study the history and future dynamics of habitat quality, which can provide lessons for optimizing habitat quality in other arid zones. Habitat quality is an important characterization of the health level of ecosystems. Unreasonable development activities have led to a degradation in habitat quality and loss of biodiversity, especially in the arid areas of northwest China where the ecological environment is fragile. In this study, we focused on the arid area in northwestern China (Hexi region). By integrating the InVEST model and PLUS model, we evaluated the dynamics of habitat quality in the Hexi region from 1990 to 2020 under the background of land use change, and simulated the habitat quality in this area in 2030 under different scenarios. The results showed that: (1) From 1990 to 2020, the areas of farmland, waterbodies, and built-up land increased by 2343.26 km2, 416.42 km2 and 739.28 km2 respectively, and the area of unutilized land decreased by 3020.36 km2. In terms of changes in land use type, unutilized land changed the most. (2) From 1990 to 2020, the habitat quality increased by 1.07 %, spatially showed a high distribution pattern along the Qilian Mountains and a low distribution pattern in the remaining area. The spatial change was dominated by stabilization, and the rank change was mainly from poor habitat quality areas to good habitat quality areas. (3) Under the scenario of natural development (ND), the future built-up land area will rapidly increase by 989 km2. In the ecological protection (EP) scenario, the areas of forest and grassland will increase by 10476 km2, the expansion of cultivated land and built-up land will be effectively curbed, and the habitat quality will be greatly improved. (4) In 2020–2030 (ND scenario), land use change will cause a certain degree of degradation of habitat quality. In 2020–2030 (EP scenario), land use change will promote the improvement of habitat quality. In addition, through this study, we provide a new method to quantify the relationship between land use and habitat quality. [Display omitted] [ABSTRACT FROM AUTHOR]

China–Myanmar oil and gas pipelines in Southwest China guarantee the energy security of China. Due to poor geographical circumstances, the safety of pipelines is seriously threatened by natural disasters. Therefore, there is a crucial, practical significance to establishing a model of leakage and diffusion of crude oil in the mountainous terrain and to conduct related applied studies. In the present study, computational fluid dynamic simulations of the dynamic diffusion process of leaking contaminants on the mountain surface was performed; the influence of the pipe pressure, landform, surface environment and leakage location on diffusion speed and range were discussed carefully. The results indicate that the variation of topographic altitude determines the path of leaking contaminants. Accordingly, an improved algorithm based on the SFD8 algorithm to predict the path of leaking contaminants at a low leakage rate was proposed; this would be instructive for an emergency response to ensure the safety of pipelines. [ABSTRACT FROM AUTHOR]

China is undergoing a rapid dietary transition as well as a changing income distribution. In this paper, we examine the impacts of income heterogeneity on the prediction of food consumption using a dataset that covered 22,210 urban households in China's 6 provinces. The two-stage Exact Affine Stone Index Implicit Marshallian Demand System (EASI demand system) model, which deals with the problem of censoring and endogeneity, is applied to estimate demand elasticity across income strata. Additionally, a dynamic simulation method considering income heterogeneity is conducted to predict future food consumption trends. The results reveal that income elasticity follows a decreasing trend with income growth. Furthermore, the results show that the consumption of major food items in the 15th period will increase by 7.9% to 42.0% over the base period. The growth potential of low-income groups is significantly higher than that of middle- and high-income groups. However, the prediction results may be overestimated if the differences in consumer behavior across income groups and the dynamic simulation procedure are not taken into account. Our study indicates that the consumption features of different income groups need to be included in food consumption forecasts. Moreover, the government should formulate food policies for different income groups to promote a sustainable food system transformation. [ABSTRACT FROM AUTHOR]

Rack railway is a new type of transportation in China. In order to solve the key problem of track change in the operation of the rack railway and to ensure that the train can pass through the rail turnout smoothly, this paper proposes a movable rack switch mechanism in the turnout based on the track-covered detachable turnout by comparing the structural forms and characteristics of the existing rack railway turnouts. Furthermore, with the finite element model of the rack switch system established, the dynamic simulation of the mechanism is carried out by using software ADAMS, and the motion force of each component in the linkage mechanism is analyzed. At the same time, the stress distribution of the mechanism is analyzed with software ANSYS. The results show that the designed movable rack switch mechanism can operate safely and reliably without dead point and the force on the operating rod of the switch system meets the requirement of the maximum output force in the movement. Besides, the maximum equivalent stress of each link for the rack switch system is less than its allowable stress, which meets the static design requirements for the mechanism. [ABSTRACT FROM AUTHOR]

Hydrogen-blended electricity-gas integrated energy system (EG-IES) utilizes surplus renewable energy power generation to blends hydrogen into the natural gas pipeline network for achieve efficient and economical large-scale hydrogen consumption and long-distance transportation. While enhancing the coupling between the power grid and gas grid, the scheduling control of such a complex system becomes increasingly important. The paper presents a dynamic model of a hydrogen blended EG-IES with high renewable energy permeability, and a modeling method that considers distribution parameters of the natural gas pipeline is obtained by using the cell segmentation and calculating the blended gas composition in real-time to avoid the assumption of constant composition. After the validation against available operational data, a case study of the certain area of Central China is simulated. The coordinate control law is reasonably designed according to the dynamic characteristics of EG-IES and the objective of realizing the load increase within the hydrogen concentration constraint, and the PID is utilized as the benchmark to compare dynamic performance. The results demonstrate that the coordinated control based on the alternate adjustment control law has no overshoot and shorter adjustment time of p l and ε about 33% and 42% than benchmark on the large delay system. • Establish a dynamic hydrogen blended electricity-gas integrated system model. • Solve the distribution parameter characteristics of the natural gas pipeline network. • Dynamic simulation and verification of a real EG-IES in Central China was carried. • Analysis of the different coordinate control performance during the load up process. [ABSTRACT FROM AUTHOR]

Coal resources perform an important role in China's energy structure. Hydraulic support is the main supporting equipment of fully mechanized mining face in coal mines. Because the hydraulic support frequently bears the impact pressure from the working face, it is very easy to cause failure of the balance jack. In order to solve the problem that the balance jack easily damaged by impact and improve the impact resistance of the hydraulic support, an improved fast response balance jack with multiple adaptive buffers was proposed in this paper. The energy dissipation characteristics of the balance jack were analyzed by establishing the mathematical model of the multiple buffering process of it. Based on ADAMS, the dynamic simulation model of the hydraulic support was constructed, and the mechanical response characteristics of the proposed balance jack and the traditional balance jack under different impact loads were compared and analyzed. By changing the equivalent stiffness of the novel balance jack system, the influence of different initial inflation pressure and length of the buffer cavity on the dynamic performance of the novel balance jack was discussed. The results show that compared with the traditional balance jack, the multi-adaptive response balance jack proposed in this paper can reduce the peak force of the hinge point by about 24.6% and the fluctuation frequency was also significantly reduced under the ultimate load condition at the front end of the top beam, which has better impact resistance. When the initial inflation pressure of the buffer cavity is 40~45 MPa and the initial length is less than 105 mm, a better buffer effect can be achieved. This study provides a new solution to solve the failure problem of the balance jack under the underground impact pressure and improve the safety and reliability of hydraulic support. [ABSTRACT FROM AUTHOR]

The ergonomics on body pressure distribution of latex product design is the future trend in bedding product design. The numerical simulation of latex pillow compression performance is critical for the optimal design of bedding products. This paper reports the use of the finite element method to simulate the compression performance of latex foam and the design of latex pillows based on the pressure distribution and displacement changes of the human pillow system. The compression performance, shear performance and tensile performance of the latex foam are tested, and the stress and strain images of three mechanical experiments are obtained. Combined with the experimental results, three methods of 'hyper foam test data, hyper foam model parameter method and low-density foam method' were used to perform uniaxial compression simulation on bedding latex foam using the finite element software ABAQUS. The simulation results and experimental values were fitted and analyzed. The analysis found that the low-density foam simulation method has the largest R2, which is 0.9871, and the simulation result is the most accurate. The optimal simulation method was selected to simulate the dynamic pressure changes and cervical displacement of the human head and latex pillow models, as well as the simulation experiments with latex pillows of different heights. The curve is fitted to obtain the second-order polynomial equations of pressure and cervical socket displacement. In contrast, it can be concluded that latex pillow products with a neck height of 100 mm are better for the supine position of younger adult women in China. [ABSTRACT FROM AUTHOR]

Excess nitrogen and phosphorus inputs are the main causes of aquatic environmental deterioration. Accurately quantifying and dynamically assessing the regional nitrogen and phosphorus pollution emission (NPPE) loads and influencing factors is crucial for local authorities to implement and formulate refined pollution reduction management strategies. In this study, we constructed a methodological framework for evaluating the spatio-temporal evolution mechanism and dynamic simulation of NPPE. We investigated the spatio-temporal evolution mechanism and influencing factors of NPPE in the Yangtze River Economic Belt (YREB) of China through the pollution load accounting model, spatial correlation analysis model, geographical detector model, back propagation neural network model, and trend analysis model. The results show that the NPPE inputs in the YREB exhibit a general trend of first rising and then falling, with uneven development among various cities in each province. Nonpoint sources are the largest source of land-based NPPE. Overall, positive spatial clustering of NPPE is observed in the cities of the YREB, and there is a certain enhancement in clustering. The GDP of the primary industry and cultivated area are important human activity factors affecting the spatial distribution of NPPE, with economic factors exerting the greatest influence on the NPPE. In the future, the change in NPPE in the YREB at the provincial level is slight, while the nitrogen pollution emissions at the municipal level will develop towards a polarization trend. Most cities in the middle and lower reaches of the YREB in 2035 will exhibit medium to high emissions. This study provides a scientific basis for the control of regional NPPE, and it is necessary to strengthen cooperation and coordination among cities in the future, jointly improve the nitrogen and phosphorus pollution tracing and control management system, and achieve regional sustainable development., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The harsh indoor environment in winter in the hot-summer and cold-winter zones of China and the increasing demand for winter heating from residential consumers have prompted more and more researchers to address the energy-efficient heating problem in non-centralized heating areas. A computational fluid dynamics model of a typical building was developed to analyze the dynamic heat transfer characteristics and energy consumption of interior partitions under decentralized heating in this region, of which the accuracy of the established model was proved by the relative error of less than 5% compared with the experimental measurement. Then seven typical kinds of interior partition configurations with different wall thickness, wall material, and insulation layer locations were developed and evaluated through simulation analysis. Transient heat storage ratio and cumulative heat storage ratio were proposed to demonstrate the dynamic heat transfer characteristics of interior partitions. The simulation results showed that 180 mm and 220 mm solid clay bricks can reduce energy consumption by 17.56% and 30.23%, respectively, compared with 120 mm solid clay bricks. The energy consumption of fly ash aerated concrete and solid clay brick partitions were reduced by 10.18% and 19.02%, respectively, compared with porous concrete partitions. The dynamic heat transfer characteristics of internal partitions with internal insulation were similar to those with external insulation due to the reduction in unnecessary energy consumption transferred to adjacent unheated rooms by about 20% compared to that without insulation. And the heat consumption of interior partitions under convective heating was 17.3% higher than under radiant heating. [ABSTRACT FROM AUTHOR]

Revealing the long-term development trajectory and peak scenarios of the urban residential building sector is crucial for formulating targeted emission reduction strategies and contributing to achieving the "Dual carbon" target. Given that, significant variables affecting carbon emissions from urban residential buildings (URBCE) at both macro and end-use building levels are identified in this study. Furthermore, an innovative dynamic simulation model is developed by integrating the Monte Carlo simulation model with the Kaya identity model, taking into account the uncertainties of the variables. Subsequently, the long-term evolution trajectories, potential emission peaks, and peak time of the URBCE close to 2060 in China's hot summer and cold winter (HSCW) zone are simulated. Results indicate that URBCE is expected to reach its peak of 272.43 Mt CO 2 in 2040 under the baseline scenario. Through the dynamic simulation, the probable peak time of energy consumption in the HSCW zone is 2044 (±1.85), with a peak of 145.42 (±6.91) Mtce, and the possible peak time of carbon emissions is probably 2039 (±1.60), with a peak of 271.93 (±13.40) Mt CO 2. According to dynamic sensitivity analysis, carbon emission factor, per capita residential space, and heating energy intensity can promote the peak size and timing. These findings lay a robust foundation for the formulation of regionally specific carbon reduction targets and initiatives. Dynamic simulation results of peaking time and peak value of URBEC and URBCE. [Display omitted] [ABSTRACT FROM AUTHOR]

Stepover structures are widely distributed in natural fault systems. The jump distance is typically easier to identify than both the stepover location and the overlap distance because of the presence of lakes and sedimentary basins around the stepover. Using the curved grid finite‐difference method, we first conducted a 3D spontaneous dynamic rupture simulation of the 1833 Songming earthquake on a continuous model of the western Xiaojiang fault to estimate the regional stress azimuth. Then, we performed rupture process simulations with different stepover structure models on the western Xiaojiang fault to investigate the effects of the stepover location and overlap distance on the dynamic rupture process. In addition, we analyzed the fault strength ratio S and rupture velocity of the preferred fault models and discussed the occurrence of supershear rupture during the Songming event. Finally, we simulated the strong ground motion with the preferred fault models for the 1833 Songming earthquake. Our simulation results suggest that the optimal regional maximum principal stress azimuth during the Songming event was N20°W. Our simulations further reveal that the Qingshuihai stepover is located in the middle of Qingshuihai Lake, and the overlap distance is 6 km; in contrast, the location of the Yangzonghai stepover is located in the southern part of Yangzonghai Lake, and the overlap distance is not constrained. Furthermore, our numerical simulation indicates that the Songming earthquake exhibited supershear rupture; however, this supershear rupture is not sustained and is easily affected by the friction parameters and nucleation location. Key Points: We model the dynamic rupture process of the 1833 M 8.0 Songming, China, earthquakeThe results show the roles that stepover location and overlap distance have on the dynamic rupture and ground motionsThe 1833 Songming earthquake may have exhibited supershear rupture [ABSTRACT FROM AUTHOR]

It is important to understand the response of vegetation dynamics and surface water budget to the changing climate. To investigate the effects of vegetation and climate change on evapotranspiration and runoff on a basin scale, the SSiB4T/TRIFFID (SSiB4/TRIFFID coupled with TOPMODEL) is used to perform long-term dynamic simulations of vegetation succession and the water balance under different climate scenarios for a subalpine basin. The results of all experiments show that fraction of vegetation changes from a dominance of C3 grasses to tundra shrubs and then gradually approaches equilibrium with a dominance of forests. Change to evapotranspiration is very sensitive to temperature changes but is not sensitive to precipitation changes when the temperature remains unchanged. Runoff is very sensitive to changes in both temperature and precipitation. In the increase of temperature, evapotranspiration of forests increases the most among the three vegetation types. From the control run to the [T+5, (1+40%)P] run (A temperature increase of 5 °C, an increase in precipitation of 40%), the role of forests in increasing runoff changes to a reduction in runoff. [ABSTRACT FROM AUTHOR]

With the growing intensity of cooperation, the partners in the manufacturing supply chain (SC) raise stricter requirements for information sharing (IS) within the SC, which has been an effective capability to improve the performance of manufacturing SC. To reveal the influence of IS on SC performance, this paper firstly carries out a theoretical analysis on the influencing factors of IS, SC integration and SC performance, and builds a theoretical model of the IS's impacting on SC performance. Next, valid index data were obtained by investigating typical manufacturing enterprises in Yangtze River Delta region of China. Then, according to the dynamics system flow of IS influence on SC performance, the proposed theoretical model would be modeled from system dynamics and simulated by Vensim PLE software. The results show that IS among manufacturing SC nodes enhances the SC performance via SC integration; when SC integration is suitable for IS, SC performance will be improved as long as the IS amount is greater than zero; however, excessive IS would reduce the quality and weaken the amount of IS; overall, the degree of IS and SC integration are the key to better SC performance. This implies that how to improve IS among SC partners is a very important thing in manufacturing SC management. And, it also enlightens that enterprise managers should pay attention to establish a high-level trust relationship with SC partners, achieve high-quality IS with a wider range, and then promote the SC system more integrated to improve its operational performance. [ABSTRACT FROM AUTHOR]

One of the major ways of delivering renewable energy generation from large-scale energy bases in northeast, northwest, and northern China, is to bundle the power from wind-photovoltaic-thermal units and then transmit it by alternating current/direct current (AC/DC) systems. The interactions among wind power units, photovoltaic (PV) power units, and high voltage direct current (HVDC) systems make the stability of the interconnected power system more complicated. In this paper, a framework model of wind-PV-thermal-bundled power transmitted by AC/DC systems is constructed based on the mathematical models of thermal power units, wind power units, PV power units, and HVDC transmission systems. Considering the fluctuations of wind power outputs and PV power outputs, a small-signal stability model of an interconnected power system with wind-PV-thermal-bundled power transmitted by AC/DC systems is established based on an existing stability theorem. The interactions among various forms of energy and their impacts on wind-PV-thermal-bundled power transmitted by AC/DC systems are studied through theoretical analysis and dynamic simulation. A sample interconnected power system is used to demonstrate the proposed method. It is shown by simulation results that the wind-PV-thermal-bundled power transmission distance; the electrical distance among wind power units, PV power units, and thermal power units; the grid-connected capacities of wind, PV, and thermal power units; and the power loading ratios of AC lines over DC lines all have various degrees of impacts on the stability of the interconnected power system. [ABSTRACT FROM AUTHOR]

Rapid urbanization leads to dramatic changes in land use patterns, and the land use/cover change (LUCC) can reflect the spatial impact of urbanization on the ecological environment. Simulating the process of LUCC and predicting the ecological risk future changes can provide supports for urban ecological management. Taking the Yangtze River Delta Urban Agglomeration (YRDUA), China as the study area, four developmental scenarios were set on the basis of the land use data from 2005 to 2015. The temporal land use changes were predicted by the integration of the system dynamic and the future land use simulation (SD-FLUS) model, and the geographically weighted regression (GWR) model was used to identify the spatial heterogeneity and evolution characteristics between ecological risk index (ERI) and socio-economic driving forces. Results showed that: 1) From 2005 to 2015, the expansion of construction land (7670.24 km2) mainly came from the occupation of cultivated land (7854.22 km2). The Kappa coefficient of the SD-FLUS model was 0.886, indicating that this model could be used to predict the future land use changes in the YRDUA. 2) Gross domestic production (GDP) and population density (POP) showed a positive effect on the ERI, and the impact of POP exceeded that of GDP. The ERI showed the characteristics of zonal diffusion and a slight upward trend, and the high ecological risk region increased by 6.09%, with the largest increase. 3) Under different developmental scenarios, the land use and ecological risk patterns varied. The construction land is increased by 5.76%, 7.41%, 5.25% and 6.06%, respectively. And the high ecological risk region accounted for 12.71%, 15.06%, 11.89%, and 12.94%, correspondingly. In Scenario D, the structure of land use and ecological risk pattern was better compared with other scenarios considering the needs of rapid economic and ecological protection. This study is helpful to understand the spatio-temporal pattern and demand of land use types, grasp the ecological security pattern of large-scale areas, and provide scientific basis for the territory development of urban agglomeration in the future. [ABSTRACT FROM AUTHOR]

Loess cave dwellings are the most typical style of regional architecture in northwest China; now, there are still tens of millions of people living in them. The northwest is an earthquake-prone area, and cave dwellings have suffered a lot of damage in previous moderate and strong earthquakes, so their earthquake resistance has attracted people's attention. At present, the seismic analysis of aboveground building structures is relatively mature, while the seismic analysis of loess cave dwellings is less researched. To study the seismic response of loess cave dwellings, a single-hole cliff-side loess cave dwelling located in Yangjialing revolution former sites of Yan'an City of northwest China was investigated and surveyed; the three-dimensional numerical model was established by MIDAS/GTS NX. Combining the historic earthquake damage investigation, dynamic time-history analysis of the single-hole loess cliff-side cave dwelling subject to four horizontal earthquake actions was conducted to determine the weak positions, failure characteristics, and the corresponding displacement and stress of the loess cave dwelling under earthquake load. The results show that the loess has an amplification effect on the seismic waves, the arch vault is a key factor to the stability of the loess cave dwellings, the cliff-side loess cave dwellings in an 8-degree area cannot be used to continue living, and the entrance to loess cave dwellings is the most dangerous place when the earthquake happens. [ABSTRACT FROM AUTHOR]

Die EU, die USA und China stellen heute die Hälfte des weltweiten Energiebedarfs. Um eine höhere Energieeffizienz zu erreichen, werden derzeit die Bauvorschriften in der EU und den USA verschärft. Die wachsende Bedeutung von großflächigen Glaselementen in moderner Architektur veranlasst die Untersuchung von möglichem Optimierungspotential vor allem in der Entwurfsphase. Die wesentliche Herausforderung besteht darin, diese mit größtmöglichem Energiesparpotential zu vereinen. Aus einer entsprechenden Kombination von unterschiedlichen Materialien kann eine gesteigerte Ressourceneffizienz der Gesamtkonstruktion resultieren. Zur Bewertung dieser Möglichkeit werden Holz‐Glas‐Fassaden konventionellen Fassaden gegenübergestellt. Dieser Vergleich erfolgt hinsichtlich der Materialwahl und anhand von daraus resultierenden thermisch dynamischen Gebäudesimulationen, sowie ökologischen Evaluierungen. Resource‐efficient planning of large‐scale timber‐glass facades | ecological and energetic evaluation. The EU, the USA and China account for half of global energy demand. In order to achieve higher energy efficiency, building regulations in the EU and the USA are currently being tightened. The growing importance of large‐scale glass elements in modern architecture leads to the investigation of possible optimization potential, especially in the design stage. The main challenge is to combine these with the greatest possible energy saving potential. An appropriate combination of different materials can result in increased resource‐efficiency of the overall design. To evaluate this possibility, the timber‐glass facades are compared with conventional facades. This comparison is made with regard to the choice of materials and the resulting thermal dynamic building simulations, as well as ecological evaluations. [ABSTRACT FROM AUTHOR]

Global warming is currently the biggest problem. China is the world's highest CO2 emitter. The Chinese authorities agreed to overcome global pollution per the current Paris treaty and have shown deep concern regarding global warming. Hence, policymakers are paying attention to economic policy uncertainty. Motivated by this issue, the study examines the effect of energy use, economic policy uncertainty, and economic growth on China's CO2 emissions from 1970 to 2018 by employing a novel dynamic ARDL simulation model. The findings show that energy use and economic growth have statistically substantial long-run and short-run positive effects on CO2 emissions. However, economic policy uncertainty has a statistically insignificant effect on CO2 emissions, due to firms' sustainability policies. Energy use can have valuable policy consequences, particularly for environmental sustainability. Therefore, based on the empirical findings, the crucial partnership and feedback on China's carbon emission policy should be carried forward. [ABSTRACT FROM AUTHOR]