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Copyright of Acta Scientiarum Naturalium Universitatis Pekinensis is the property of Editorial Office of Acta Scientiarum Naturalium Universitatis Pekinensis and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The work is devoted to the application of various nonlinear dynamics methods to identify interactions in short noisy time series extracted from biological rhythms related to the respiratory, cardiovascular and nervous systems. These interactions are considered as transitions to synchronized states, as the coupling directionality and the delay time in the influence of one system on another. For the analyzed data, the relationship between these rhythms is due to the fact that the neurons of medulla are related to the brain response to changes in blood pressure and respiration during external pain stimulation. Phase synchronization between the variability of blood pressure and respiratory fluctuations in response to these stimuli was established in half of the analyzed time series using methods for assessing phase synchronization based on finding instantaneous phases by the synchrosqueezed wavelet transform and based on calculating the recurrences of phase trajectories. For unsynchronized time series, a predominantly unidirectional influence of respiratory rhythm fluctuations on the blood pressure variability was obtained by the method of phase dynamics modeling and the method of estimating recurrence probabilities. For two third of the data, a unidirectional influence of the blood pressure variability on the neuronal variability was determined, and the remaining data were characterized by a bidirectional relationship between the neuronal and blood pressure variability. Delay time estimation by phase dynamics modeling showed reduced time of influence of the blood pressure variability on the neuronal variability in bidirectional coupling compared to the influence of the neuronal variability on the blood pressure variability. [ABSTRACT FROM AUTHOR]

Abstract Vibration quality is a vital indicator for assessing the progress of modern equipment. The dynamic vibration absorber (DVA) based on the acoustic black hole (ABH) feature is a new passive control method that manipulates waves. It offers efficient energy focalization and broad-spectrum vibration suppression, making it highly promising for applications in large equipment such as aircraft, trains, and ships. Despite previous advancements in ABH-DVA development, certain challenges remain, particularly in ensuring effective coupling with host structures during control. To address these issues, this study proposes a partitioned ABH-featured dynamic vibration absorber (PABH-DVA) with partitions in the radial direction of the disc. By employing a plate as the host structure, simulations and experiments were conducted, demonstrating that the PABH-DVA outperforms the original symmetric ABH-DVA in terms of damping performance. The study also calculated and compared the coupling coefficients of the two ABH-DVAs to uncover the mechanism behind the enhanced damping. Simulation results revealed that the PABH-DVA exhibits more coupled modes, occasionally with lower coupling coefficients than the symmetric ABH-DVA. The influence of frequency ratio and modal mass was further analyzed to explain the reasons behind the PABH-DVA's superior damping performance. Additionally, the study discussed the impact of the number of slits and their orientation. This research further explains the coupling mechanism between the ABH-DVA and the controlled structure, and provides new ideas for the further application of ABH in engineering.

In recent years, rapid city development has significantly impacted the microclimate environments in urban blocks. Many studies have shown that varied built-up environmental factors lead to corresponding degrees of influence on microclimate. Urban blocks are one of the most concentrated urban settlements, and their impact on the urban climate and environment cannot be ignored. Taking the Fengtai district in Beijing as an example, using the ArcGIS platform inputted with meteorological data and built-up environment data, this study selected climate-sensitive units in the Fengtai district, of which 746 highly sensitive block units were obtained. SPSS software was used to analyze the correlation between built-up environmental factors and climate elements, and the relationship between the degree of influence and magnitude was analyzed using a regression equation. An optimization strategy for built-up environments on an urban block scale was proposed. A model for improving the climate environment at the urban block scale is summarized. Coupling study between climate environment and influencing factors at the urban block scale is an effective way to deal with the improvement of the urban microclimate environment and refinement transformation in the post-epidemic era.

Vibration quality is a vital indicator for assessing the progress of modern equipment. The dynamic vibration absorber (DVA) based on the acoustic black hole (ABH) feature is a new passive control method that manipulates waves. It offers efficient energy focalization and broad-spectrum vibration suppression, making it highly promising for applications in large equipment such as aircraft, trains, and ships. Despite previous advancements in ABH-DVA development, certain challenges remain, particularly in ensuring effective coupling with host structures during control. To address these issues, this study proposes a partitioned ABH-featured dynamic vibration absorber (PABH-DVA) with partitions in the radial direction of the disc. By employing a plate as the host structure, simulations and experiments were conducted, demonstrating that the PABH-DVA outperforms the original symmetric ABH-DVA in terms of damping performance. The study also calculated and compared the coupling coefficients of the two ABH-DVAs to uncover the mechanism behind the enhanced damping. Simulation results revealed that the PABH-DVA exhibits more coupled modes, occasionally with lower coupling coefficients than the symmetric ABH-DVA. The influence of frequency ratio and modal mass was further analyzed to explain the reasons behind the PABH-DVA's superior damping performance. Additionally, the study discussed the impact of the number of slits and their orientation. This research further explains the coupling mechanism between the ABH-DVA and the controlled structure, and provides new ideas for the further application of ABH in engineering. [ABSTRACT FROM AUTHOR]

During the configuration process of open architecture products (OAPs), adaptive change is inevitable to meet customers' personalised demands. However, the coupling between modules makes adaptive changes of open architecture products more difficult. For the coupling between modules in open architecture product design, an approach to analysing the coupling between modules is proposed. The implications of adaptive change for open architecture products are explained, and the interface relationships among the common platform, customised modules, and personalised modules are analysed. The coupling modes of three cases are discussed, i.e. the coupling between modules under the same branch, between modules under different branches with only functional collaboration, and between modules under different branches with function-structure correlation. The coupling degrees are calculated with consideration of the number of connections between modules and their comprehensive correlation degree. The structural complexity of the module is considered by development cost, development time, change cost, and change time, which is expressed with the information content in axiomatic design. Based on structural complexity, the dependency, and coupling degree between modules, the calculation method of change impact degree between modules is presented. The method on coupling analysis between modules in open architecture product design for personalised electric winches is illustrated. [ABSTRACT FROM AUTHOR]

Urbanization inevitably interfered with the supply and demand of ecosystem services (ESs), which has a crucial impact on the ESs balance. Scientific exploration and clarification of the coupling and decoupling relationship between them can effectively reveal the disturbance of urbanization to the ecosystem, which can help to reasonably manage and protect the ecosystem. Previous studies have paid more attention to the coupling relationship but less attention to the decoupling relationship. This study comprehensively reflected urbanization from the three aspects of construction land, population, and economy and used the evaluation matrix to measure ESs. On this basis, coupling and decoupling analyses were taken to fully clarify the complex relationship between urbanization and ESs balance in China, so as to provide a reference for the formulation of relevant policies. Coupling aspect, the coupling degrees between the proportion of construction land (CLP) and ESs balance index (ESBI) were higher only in the central and eastern plains. The coupling degrees between population density (PD) and ESBI, economic density (ED) and ESBI, and land development index (LDI) and ESBI were only lower in the central and eastern plains than in other regions. Decoupling aspect, strong, weak negative, weak, and strong negative decoupling were the main decoupling types between urbanization and ESs balance in China. Among them, the proportion of the strong decoupling type is much higher than other types, which proves the opposite relationship between the two. Weak decoupling can not only promote economic growth and social development but also protect the ecological environment and biodiversity, which is a type of sustainable development and an ideal state that urbanization should pursue. The results can provide scientific guidance for the formulation of differentiated ecosystem management policies. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Southeast University / Dongnan Daxue Xuebao is the property of Journal of Southeast University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Promoting the progression of agricultural modernization and digital economy integration has introduced new opportunities and challenges for the advancement of China's agriculture towards high-quality development. Based on panel data from 31 provinces in China from 2011 to 2020, we use the entropy method, coupling coordination model, spatial auto-correlation model, and obstacle model to explore the degree of coupling coordination and influencing factors of China's digital economy and agricultural modernization. The results show the following. (1) China's digital economy and agricultural modernization are underdeveloped on the whole, but they show a positive upward trajectory. The digital economy is outpacing the development of agricultural modernization, but the gap between the two is gradually narrowing. (2) The degree of coupling coordination between China's digital economy and agricultural modernization shows an upward trend. Additionally, there is regional heterogeneity and uneven development of the coupling coordination, i.e., it is high in the eastern region and low in the western region, accompanied by strong spatial agglomeration and correlation. (3) The main obstacle to the progression of the digital economy is digital infrastructure, while the main obstacle to the progression of agricultural modernization is agricultural production capacity. Based on China's national conditions, we should fully promote the role of the digital economy, explore plans and strategies for promoting the digital economy in differentiated areas, mitigate any imbalanced development, promote the coordinated development of the digital economy and agricultural modernization, and provide decision-making references for the implementation of a digitized China, as well as rural revitalization strategies. [ABSTRACT FROM AUTHOR]

Exploring urban spatial structures through spatial coupling analysis methods is an important method to provide theoretical support for the construction of sustainable urban structures. In order to make up for the neglect of POI species differences in previous studies, information entropy was introduced to calculate POI confusion, and a comprehensive POI index was constructed by combining kernel density and the entropy weight method; impervious surface coverage was extracted based on land cover data. The spatial distribution of the Beijing–Tianjin–Hebei urban agglomeration and some typical cities was analyzed by coupling two types of data using the dual-factor mapping method. The research indicates the following: (1). The spatial distribution of the two sets of data in the Beijing–Tianjin–Hebei region is highly consistent, indicating a state of high spatial coupling; Beijing has the highest proportion of coupling in the same region at the city level (73.39%). (2). The areas with different coupling of the two types of data are mainly distributed in the urban fringe areas transitioning from the city center to the suburbs, as well as in large-scale areas with single functionality such as airports, scenic spots, and ports. This study shows that analysis combining the POI comprehensive index and impervious surface coverage can effectively characterize urban spatial structure characteristics, providing a new perspective for the study of the spatial structure of the Beijing–Tianjin–Hebei urban agglomeration. It is of great significance for a deeper understanding of the laws of urban agglomeration spatial structures and guiding the coordinated development of the Beijing–Tianjin–Hebei urban agglomeration. [ABSTRACT FROM AUTHOR]

Revenue Management of Service Systems under Incomplete Information Revenue management with reusable resources finds many important applications in today's economy, such as cloud computing services, car/bicycle rental services, ride-hailing services, hotel management, project team management, and call center services. The existing literature predominantly assumes that the stochastic demand and service processes are given as an input to the models, and the pricing decisions are made with full knowledge of the distributional information. However, in practice, the decision maker may not know how demand or service rates react to price changes. Thus, the decision maker needs to learn the underlying mapping between prices and rates from past observations, while maximizing the total expected revenue on the fly. In "Online Learning and Pricing for Service Systems with Reusable Resources", H. Jia, C. Shi, and S. Shen developed a series of online learning algorithms for revenue management problems with reusable resources and showed that they admit an optimal regret bound. We consider a price-based revenue management problem with finite reusable resources over a finite time horizon T. Customers arrive following a price-dependent Poisson process, and each customer requests one unit of c homogeneous reusable resources. If there is an available unit, the customer gets served within a price-dependent exponentially distributed service time; otherwise, the customer waits in a queue until the next available unit. In this paper, we assume that the firm does not know how the arrival and service rates depend on posted prices, and thus it makes adaptive pricing decisions in each period based only on past observations to maximize the cumulative revenue. Given a discrete price set with cardinality P, we propose two online learning algorithms, termed batch upper confidence bound (BUCB) and batch Thompson sampling (BTS), and prove that the cumulative regret upper bound is O ˜ (P T) , which matches the regret lower bound. In establishing the regret, we bound the transient system performance upon price changes via a novel coupling argument, and also generalize bandits to accommodate subexponential rewards. We also extend our approach to models with balking and reneging customers and discuss a continuous price setting. Our numerical experiments demonstrate the efficacy of the proposed BUCB and BTS algorithms. Funding: This research was partially supported by an Amazon research award and the Department of Energy [Award DE-SC0018018]. [ABSTRACT FROM AUTHOR]

The establishment of an eco-industrial demonstration park is based on the principles of sustainable development and aims to achieve social progress and economic growth before ultimately evolving into a fully developed industrial ecosystem. This study explores the relationship between the ecological environment and socioeconomic development in Zhengzhou Economic Development Zone (area of 158.7 km2), China. By analyzing the landscape patterns and changes in ecosystem service values over the periods of 2010, 2015, and 2019, results revealed a remarkable shift in land use in this area from 2010 to 2019. Particularly noteworthy was the remarkable growth in forest lands, which expanded from 0.98 km2 in 2010 to 23.42 km2 in 2019, whereas cultivated and bare lands decreased by 47.55% and 73.81%, respectively. The value of ecosystem services experienced a continuous increase and reached 13.3009 billion yuan in 2019. This study also examined the coordination degree of socioeconomic development and ecological environment coupling and found considerable progress from 2010 to 2019. The coupling degree values of 0.129, 0.809, and 0.960 for the aforementioned years indicated a remarkable improvement in synergistic and integrated development between the socioeconomic system and the ecosystem in this area. The landscape patterns in this area underwent noteworthy transformations. [ABSTRACT FROM AUTHOR]

Analyzing the spatio-temporal relationship between socio-economics and land-use structure at the micro-scale is crucial for effective spatial governance in large cities. This paper focuses on Beijing, utilizing long time-series remote sensing images and multi-source data spanning 30 years. We employ spatio-temporal clustering based on kilometer grid cells and a community-scale multi-factor aggregation method to categorize the linkages and spatio-temporal matching of population, GDP, land development, and ecological protection at the community level in a problem-oriented approach. Results indicate significant changes in Beijing's population, GDP, and land use, with a 11.53% increase in land development intensity. We identify significant temporal and spatial disparities between population–GDP dynamics, population–land development trends, and GDP–land development patterns, underscoring the multifaceted challenges inherent in urban governance. Areas characterized by lagging population concentration, sluggish economic growth, rampant land development, and ecological fragility collectively encapsulate notable portions of Beijing's expansive urban terrain. Mismatches pose governance risks, with medium to high-risk communities comprising 18.08% of community units and high-risk types representing 4.27% in Beijing. These discrepancies pose formidable governance risks, with communities ranging from moderate to high-risk categories, necessitating tailored interventions to address their unique challenges. This systematic exploration of comprehensive governance issues within mega-cities promises to furnish decision-makers with invaluable insights, facilitating nuanced and strategic urban governance approaches tailored to the intricacies of urban dynamics and challenges. [ABSTRACT FROM AUTHOR]

Through on-site investigation, the number, locations, and causes of death in the Luding earthquake were obtained. Based on an analysis of the causes of death, 44.1% of the deaths were caused by building collapse, and 54.8% were caused by earthquake-induced geological effects. Therefore, it is particularly important to conduct research on targeted methods for assessing casualties for emergency rescue work after earthquakes. First, this article analyzes the number of deaths as a result of different earthquake intensities and building types and, combined with data from 81 on-site survey points (lethality levels and quantity and ratios of different types of buildings), obtains the regional lethality levels for different intensities and administrative units in the study area (intensity VIII and IX areas). Second, based on on-site investigation results of points at which secondary geological effects (landslides and rolling stones) occurred, and by combining parameters, such as the slope, slope direction, slope curvature, and distance from the fault, this study obtains the risk level of earthquake-induced landslides. On this basis, a coupling analysis is conducted on the seismic landslide risk level and lethality level. The results show a positive correlation between the risk level and the lethality level; the higher the risk level, the higher the corresponding lethality level is, but this relationship is not absolute. The Pearson's correlation coefficient for the fitting results is 0.70828, the coefficient of determination R2 is 0.50102, and the mean squared (MS) is 0.029. The results of the sensitivity analysis of the two levels show values that are above the average level, with the prediction accuracy of the landslide risk level and lethality level being 0.708 and 0.609, respectively. The fitting results show average values at a moderate level; by constructing a fitting relationship between the landslide risk level and lethality level, the relationship can provide ideas and feasibility for constructing a lethality matrix for secondary geological disasters during earthquakes. Furthermore, it is possible to quickly evaluate the number of deaths due to secondary geological effects of the earthquake. [ABSTRACT FROM AUTHOR]

During automobile crashes, the main behavior of plastics in the vehicle is bending deformation. Because of this, it is important to accurately calculate the edge stress and allowable stress on structural surfaces. For that purpose, it is necessary to consider the distribution of the fiber orientation angle and degree in the plate thickness direction. In a general coupled analysis for injection-molded materials, a material model is created based on the physical properties obtained from an arbitrary test piece. Therefore, even if the orientation angle in each part to be analyzed is taken into consideration, the degree of orientation is constant in each part, and the degree of orientation distribution in the plate thickness direction is also treated as constant. We tried to improve the accuracy of crash analysis by calculating the edge stress and allowable stress with high accuracy by considering the distribution of orientation angle and degree in the plate thickness direction. For that purpose, we created a model that calculates properties of composite materials from resin and fiber properties, and a process that maps the distribution of orientation angle and degree in the plate thickness direction to each integration point of the shell element in structural molding analysis. [ABSTRACT FROM AUTHOR]

Blanket is of vital importance for engineering application of the fusion reactor. Nuclear heat deposition in materials is the main heat source in blanket structure. In this paper, the three-dimensional method for thermal-hydraulics/neutronics coupling analysis is developed and applied for the full-scale module of the helium-cooled ceramic breeder tritium breeding blanket (HCCB TBB) designed for China Fusion Engineering Test Reactor (CFETR). The explicit coupling scheme is used to support data transfer for coupling analysis based on cell-to-cell mapping method. The coupling algorithm is realized by the user-defined function compiled in Fluent. The three-dimensional model is established, and then the coupling analysis is performed using the paralleled Coupling Analysis of Thermal-hydraulics and Neutronics Interface Code (CATNIC). The results reveal the relatively small influence of the coupling analysis compared to the traditional method using the radial fitting function of internal heat source. However, the coupling analysis method is quite important considering the nonuniform distribution of the neutron wall loading (NWL) along the poloidal direction. Finally, the structure optimization of the blanket is carried out using the coupling method to satisfy the thermal requirement of all materials. The nonlinear effect between thermal-hydraulics and neutronics is found during the blanket structure optimization, and the tritium production performance is slightly reduced after optimization. Such an adverse effect should be thoroughly evaluated in the future work.

Introduction: Arid and semi-arid regions encompass nearly 40% of the Earth's land surface and are characterized by extensive undeveloped land, scarce water resources, and fragile ecosystems. The arid northwestern China is a representative arid and semi-arid region. It has developed rapidly in recent years, leading to a significant increase in human activity. This increased activity has had a pronounced impact on the ecosystem, posing a major challenge to the environment. The close relationship between human activities and ecosystem service value (ESV) is crucial for the healthy development of both humans and ecosystems. However, the intricate nature of this relationship and the degree to which they are codependent remain unclear and require further investigation. Methods: This study investigates the impact of human activities on land use intensity (LUI) and degree of urbanization (URB). It comprehensively evaluates the spatial and temporal distribution of human activities and ESV, quantifying their coordination through coupling models. Results: This work provides valuable insights and theoretical support for promoting the coordinated development of human activities and ESV. Overall, the LUI in the arid northwestern region decreased (from 0.485 in 2000 to 0.459 in 2020), while the URB increased (from 0.060 in 2000 to 0.087 in 2020). The ESV significantly increased, with a total growth of 556.58 billion yuan. In prefecture- level cities, the growth in ESV values ranges from 75.19 yuan/hm2 to 10,062.49 yuan/hm2.The coupling coordination degree between ESV and LUI has changed over time, transitioning from uncoordinated development to coordinated development. In addition, the coordination between ESV and URB has evolved from uncoordinated development to transitional coordination. The level of coordination between human activities and ESV in provincial capital cities significantly influences the coordination in surrounding cities. Discussion: In conclusion, effective development recommendations are provided based on the ESV, LUI, and URB of different cities, along with a proposed development strategy for ecosystem service functions that aligns with the 14th Five-Year Plan and "Vision 2035" of each province. This work provides important insights into the relationship between human activities and ESV, and its findings can be used to guide coordinated and sustainable urban development. [ABSTRACT FROM AUTHOR]

Copyright of Control Theory & Applications / Kongzhi Lilun Yu Yinyong is the property of Editorial Department of Control Theory & Applications and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

By deconstructing the dimensions of rural tourism and rural revitalization and constructing a coupled conceptual model, a coupled evaluation model is constructed. Yannanfei Tea Field Resort in Guangdong is taken as a research case for empirical analysis, to explore the coupled development trend of the two. The results show that ① the tourism development of Guangdong Yannanfei Tea Field Resort has a good synergistic relationship with rural revitalization. The two complement and promote each other, and rural tourism has significantly promoted the development of rural revitalization. ② The coupling development of tourism development and rural revitalization in Guangdong Yannanfei Tea Field Resort is divided into coupling imbalance period and coupling coordination period. The results indicate that the coordination between the two has not yet reached a level of good coordination and high-quality coordination. It is recommended that the resort should fully utilize the opportunity of rural revitalization strategy, increase investment in rural tourism, promote the transformation and upgrading of the resort, impel the integration of tea and tourism, and develop new business model of tea-tourism rural vacation. [ABSTRACT FROM AUTHOR]

In order to evaluate the safety of salvage operation, a numerical model of the coupling dynamic response characteristics of the “Yangtze River Estuary II” salvage system is established based on the three-dimensional potential flow theory and the Skempton formula. The model has been verified by actual measurement and is used in the safety analysis of the whole salvage process. The research results show that special attention needs to be paid to the motion response of the salvage system and the tension changes of the lifting and mooring lines in the two stages of bottom-off and partial water-out in the overall salvage process. With the increase of wave height and spectral peak period, the motion response of the salvage system and the extreme value of cable tension increase. The influence of wave direction on the six-degree-of-freedom movement of the system is more complicated, and the extreme value of the tension of the lifting cable increases significantly under the action of oblique waves. According to the calculation of the safety factor of the cable, when formulating a salvage plan, an appropriate lifting speed should be selected, and at the same time, salvage operations should be avoided in waves of 20°—70°.

Exploring urban spatial structures through spatial coupling analysis methods is an important method to provide theoretical support for the construction of sustainable urban structures. In order to make up for the neglect of POI species differences in previous studies, information entropy was introduced to calculate POI confusion, and a comprehensive POI index was constructed by combining kernel density and the entropy weight method; impervious surface coverage was extracted based on land cover data. The spatial distribution of the Beijing–Tianjin–Hebei urban agglomeration and some typical cities was analyzed by coupling two types of data using the dual-factor mapping method. The research indicates the following: (1). The spatial distribution of the two sets of data in the Beijing–Tianjin–Hebei region is highly consistent, indicating a state of high spatial coupling; Beijing has the highest proportion of coupling in the same region at the city level (73.39%). (2). The areas with different coupling of the two types of data are mainly distributed in the urban fringe areas transitioning from the city center to the suburbs, as well as in large-scale areas with single functionality such as airports, scenic spots, and ports. This study shows that analysis combining the POI comprehensive index and impervious surface coverage can effectively characterize urban spatial structure characteristics, providing a new perspective for the study of the spatial structure of the Beijing–Tianjin–Hebei urban agglomeration. It is of great significance for a deeper understanding of the laws of urban agglomeration spatial structures and guiding the coordinated development of the Beijing–Tianjin–Hebei urban agglomeration.

To promote the integrated development of the sports and tourism industry, create new formats, and drive the development of five happiness industries as tourism, culture, sports, health, and elderly care, promote local industrial layout and high-quality development, the author proposes an optimization model for the integration of sports industry digitalization and tourism industry. Based on the coupling coordination theory and fusion theory, the author chooses city A as the research case, through the coupling analysis method, the integrated development level of the sports industry and the tourism industry in City A was discriminated, and the dynamic factors and hindering factors affecting the coupling were explored, and the reasons were analyzed. The results show that the index weights of the two system layers, namely, the sports and tourism industry system layers, are 0.5 and 0.5, respectively. The top five weighted indicators are The number of sports-related enterprises, the number of tourist attractions, the number of travel agencies, the number of sports professionals and the number of domestic tourists received; The results of the coupling coordination degree show that in terms of degree D, there is an obvious trend of long-term stable linear increase and then a small decline, from 2010 to 2019, the D value increased from 0.28 to 1. Conclusion: The model is suitable for the practical framework of the development trend of the sports tourism industry model.

IntroductionArid and semi-arid regions encompass nearly 40% of the Earth’s land surface and are characterized by extensive undeveloped land, scarce water resources, and fragile ecosystems. The arid northwestern China is a representative arid and semi-arid region. It has developed rapidly in recent years, leading to a significant increase in human activity. This increased activity has had a pronounced impact on the ecosystem, posing a major challenge to the environment. The close relationship between human activities and ecosystem service value (ESV) is crucial for the healthy development of both humans and ecosystems. However, the intricate nature of this relationship and the degree to which they are codependent remain unclear and require further investigation.MethodsThis study investigates the impact of human activities on land use intensity (LUI) and degree of urbanization (URB). It comprehensively evaluates the spatial and temporal distribution of human activities and ESV, quantifying their coordination through coupling models.ResultsThis work provides valuable insights and theoretical support for promoting the coordinated development of human activities and ESV. Overall, the LUI in the arid northwestern region decreased (from 0.485 in 2000 to 0.459 in 2020), while the URB increased (from 0.060 in 2000 to 0.087 in 2020). The ESV significantly increased, with a total growth of 556.58 billion yuan. In prefecture-level cities, the growth in ESV values ranges from 75.19 yuan/hm2 to 10,062.49 yuan/hm2.The coupling coordination degree between ESV and LUI has changed over time, transitioning from uncoordinated development to coordinated development. In addition, the coordination between ESV and URB has evolved from uncoordinated development to transitional coordination. The level of coordination between human activities and ESV in provincial capital cities significantly influences the coordination in surrounding cities.DiscussionIn conclusion, effective development recommendations are provided based on the ESV, LUI, and URB of different cities, along with a proposed development strategy for ecosystem service functions that aligns with the 14th Five-Year Plan and “Vision 2035” of each province. This work provides important insights into the relationship between human activities and ESV, and its findings can be used to guide coordinated and sustainable urban development.

Submarine pipelines are widely adopted around the world for transporting oil and gas from offshore fields. They tend to be severely ruined by the extreme waves induced by the natural disaster, such as hurricanes and tsunamis. To maintain the safety and function integrity of the pipelines, porous media have been used to wrap them from the external loads by the submarine environment. The functions of the porous wrappers under the hydrodynamic impact remain to be uncovered before they are widely accepted by the industry. In this study, a numerical wave tank is established with the immersed boundary method as one of the computational fluid dynamics. The submarine pipelines and their porous wrappers are two-way-coupled in terms of displacement and pressure at their interfaces. The impact from the solitary waves, which approximately represent the extreme waves in the reality, on the pipelines with different configurations of the porous wrapper is investigated. The results present significant protective functions of the wrappers on the internal pipelines, transferring the impact forces from the pipelines to the wrappers. The protective effects tend to be enhanced by the porosity and thickness of the wrappers. The influence of the pipeline configurations and the marine environment are then analysed. As for the front pipeline, an increase in the gap leads to a slight increase in the horizontal forces on both the wrapper and the pipeline, but a significant increase in the vertical forces. As for the rear pipeline, because of the shield function of the front pipeline, the velocity within the gap space and the forces on the pipes are decreased with the decrease in the gap size. The complex flow fields around the pipelines with wrappers are also illuminated, implying that the protection function of the wrapper is enhanced by the wave height reduction. [ABSTRACT FROM AUTHOR]

Burgeoning urbanization is a defining challenge for global carbon emissions mitigation in the coming decades. In this context, achieving low-carbon urbanization remains an urgent issue that demands prompt solutions. The coupling and decoupling relationships between urbanization and carbon emissions play an important role in the coordination of urbanization development and carbon emissions reduction, which has rarely been explored in existing studies, especially in China at the county level. To address this gap, the coupling and decoupling relationship between the urbanization level (UL) and carbon emissions density (CED) was explored using an improved coupling degree model and the Tapio decoupling method in China at the county level from 2000 to 2020. The results showed that the UL and CED of China both exhibited increasing trends, and the spatial distribution was quite similar, with the UL increasing from 0.018 in 2000 to 0.028 in 2020 and the CED increasing from 95.163 ton/km2 in 2000 to 295.746 ton/km2 in 2020. The spatial distribution of hotspots in the UL change differed with time, whereas that in the CED change was relatively stable. However, both of them were concentrated in eastern China. The coupling degrees of the UL and CED in China were 0.348, 0.355, 0.369, 0.370, and 0.338 in 2000, 2005, 2010, 2015, and 2020, respectively, with the moderately unbalanced type (>35%) being dominant at the county level and mainly scattered in eastern China. The changes in the spatial distribution patterns of the 10 subcategories were quite limited, with the systematically balanced type being dominant (89%). The decoupling types of the UL and CED during 2000–2005, 2005–2010, and 2010–2015 were weak decoupling, while those in 2015–2020 were expansive negative decoupling. At the county level, the most significant transition occurred between expansive negative decoupling, strong decoupling, and strong negative decoupling. The proportion of strong decoupling type counties peaked in 2015–2020 (70.86%), whereas that of the strong negative decoupling type counties remained high (17.55%), scattering the country. These findings can advance policy enlightenment of low-carbon urbanization and green development for China against the backdrop of "30·60 dual carbon" goal. [ABSTRACT FROM AUTHOR]

As an integral part of urban functions, waste reduction behaviors inside the airport and outside in society form a linkage mechanism that influences each other, but the coupling mechanism between the two is not clear. In this study, we constructed a model of the interaction between airport and social waste reduction behaviors and explored the effects of internal airport factors and external social factors on airport waste reduction behaviors. The results show that both internal and external factors have a significant positive effect on passengers' behavior, with publicity and education, social norms, and laws and regulations having a greater effect. Airport internal factors (such as internal facilities, publicity and education and environmental stimulus) and social external factors (such as social norms and laws and regulations) can form a better positive feedback mechanism for waste reduction, and path coefficients for both interactions exceed 0.7. Airport publicity and education can directly improve passengers' waste reduction behaviors, and better promote the continuation of these behaviors in society. It is recommended connecting the publicity and education activities between airports and society. The social external factors are more likely to affect the behavior of airport management, and it is recommended that the design of airport management should be made more effective in developing countries that have weaker awareness of and worse social attitudes towards for waste reduction. [ABSTRACT FROM AUTHOR]

Bridge construction accidents are often caused by a variety of factors, so it is particularly important to explore the role mechanism of bridge construction accident risk factors to effectively prevent construction safety accidents and ensure the smooth construction of bridges. We collect the causes of bridge construction accidents in China from 2006 to 2023, take 126 typical cases as research samples, analyze the primary risk factors of bridge construction from four aspects (human factors, equipment factors, management factors, and environmental factors), establish a library of secondary risk factors with reference to the literature research, introduce the theory of risk coupling, and analyze the coupling mechanism and types of risk factors of bridge construction accidents. The N-K random Boolean network model (N-K model) quantifies the coupling relationship between risk factors, assesses the risk level, and uses social network analysis (SNA) to analyze the network of bridge construction accident risk factors. The results indicate that the more factors involved in risk coupling, the greater the safety risks in bridge construction. Human factors are susceptible to the influence of other elements, and environmental and management factors can directly or indirectly impact other factors. In addition, operational errors, a lack of supervision and management, inadequate safety inspections, poor management personnel, and insufficient technical capabilities are also key risk factors that need to be prevented and controlled. [ABSTRACT FROM AUTHOR]

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Analyzing the spatio-temporal relationship between socio-economics and land-use structure at the micro-scale is crucial for effective spatial governance in large cities. This paper focuses on Beijing, utilizing long time-series remote sensing images and multi-source data spanning 30 years. We employ spatio-temporal clustering based on kilometer grid cells and a community-scale multi-factor aggregation method to categorize the linkages and spatio-temporal matching of population, GDP, land development, and ecological protection at the community level in a problem-oriented approach. Results indicate significant changes in Beijing’s population, GDP, and land use, with a 11.53% increase in land development intensity. We identify significant temporal and spatial disparities between population–GDP dynamics, population–land development trends, and GDP–land development patterns, underscoring the multifaceted challenges inherent in urban governance. Areas characterized by lagging population concentration, sluggish economic growth, rampant land development, and ecological fragility collectively encapsulate notable portions of Beijing’s expansive urban terrain. Mismatches pose governance risks, with medium to high-risk communities comprising 18.08% of community units and high-risk types representing 4.27% in Beijing. These discrepancies pose formidable governance risks, with communities ranging from moderate to high-risk categories, necessitating tailored interventions to address their unique challenges. This systematic exploration of comprehensive governance issues within mega-cities promises to furnish decision-makers with invaluable insights, facilitating nuanced and strategic urban governance approaches tailored to the intricacies of urban dynamics and challenges.

Analyzing human–environment coupling is important in understanding the mechanisms and developments of human–environment systems. However, the current frameworks and approaches evaluating the relationship between human activities and the ecological environment remain limited. Integrating the vegetation-impervious surface–soil–air framework, Mann–Kendall test, correlation analysis, two-step floating catchment area method, coupling analysis, and optimal parameters-based geographical detector, this study comprehensively evaluate the environmental changes and analyzes the coupling relationship between environment and human activities, mainly in terms of habitat quality, landscape pattern, and ecological services. The study area was the Qilian Mountain National Nature Reserve in Gansu province, China, an ecologically fragile region with an environment closely linked to human activities. Along with district and county census data, various remote-sensing products (e.g., MODIS, Landsat) were used to assess the ecological level and human–environment coupling state of the study site from 2003 to 2019. The main results show: (1) The remote sensing composite index, which integrates eight ecological sub-indices, effectively captures the spatial and temporal variations of the ecological environment in the study area, providing comprehensive and detailed environmental information. (2) Analysis using the Mann–Kendall-correlation classification, coupling degree, and two-step floating catchment area methods consistently demonstrates a gradual coordination between human activities and the ecological environment in the study area. (3) In comparison to spatially interpolated population data, the remote sensing human activity index more significantly represents the spatial impact of human activities on the ecological environment. (4) The environmental aspects most strongly associated with human activities include carbon fixation and oxygen release, vegetation, humidity, and soil. (5) The ecological environment level does not uniformly deteriorate with increasing population density, and a notable alignment is observed between changes in the ecological environment and the implementation of government environmental protection policies. [ABSTRACT FROM AUTHOR]

The inkjet printing technology, based on piezoelectric microjet, realizes the high-efficiency processing of special-shaped structures, and has the advantages of high precision, high efficiency, and the ability to manufacture arbitrary complex parts. In this paper, a self-priming piezoelectric micro-jet device is proposed and its structure and microjet process are described. ANSYS two-phase two-way fluid-structure coupling simulation analysis is carried out, and the mechanism of the piezoelectric microjet is described in detail. The effects of voltage amplitude, input signal frequency, nozzle diameter, and oil viscosity on the ejection performance of the device are studied, and a set of effective control methods are summarized. Finally, the correctness of the piezoelectric microjet mechanism and the feasibility of the proposed self-priming piezoelectric micro-jet device are verified by experiments, and its ejection performance is tested. The experimental results are consistent with the ANSYS simulation results, which verifies the correctness of the experiment. [ABSTRACT FROM AUTHOR]

The inkjet printing technology based on piezoelectric micro-jets can effectively realize the efficient and high-precision processing of special-shaped structures. In this work, a nozzle-driven piezoelectric micro-jet device is proposed, and its structure and micro-jet process are described. ANSYS two-phase, two-way fluid–structure coupling simulation analysis is carried out, and the mechanism of the piezoelectric micro-jet is described in detail. The effects of voltage amplitude, input signal frequency, nozzle diameter and oil viscosity on the injection performance of the proposed device are studied, and a set of effective control methods is summarized. The correctness of the piezoelectric micro-jet mechanism and the feasibility of the proposed nozzle-driven piezoelectric micro-jet device are proved by experiments, and an injection performance test is carried out. The experimental results are consistent with the ANSYS simulation results, which confirms the correctness of the experiment. Finally, the stability and superiority of the proposed device are verified via comparation experiments. [ABSTRACT FROM AUTHOR]

Multienergy system (MES) operation has proven beneficial to the flexibility and efficiency of energy usage. Although efforts have been made toward the simulation and optimization of MESs, successful MES deployment is a grand challenge for market operations. The previous literature focuses on the modeling of the MES and the formulation of corresponding locational marginal prices (LMPs). A detailed analysis of LMP properties in an MES market-clearing model has not been fully developed. Although coupling analysis between different energy systems has been conducted from a system and power flow perspective, a coupling analysis with a specific indicator from a LMP perspective could provide operators with new insight into MES integration. Therefore, this paper first identifies six properties of the LMP in a unified MES market-clearing model. Then, based on the identified properties, two new types of critical load levels (CLL), Self-CLL and Cross-CLL, are defined and discussed to investigate the MES price pattern. Next, the Self-CLLs and Cross-CLLs for an MES are quantified by grey relation analysis (GRA) to deliver an MES coupling analysis from the perspective of LMP patterns. The identified properties and proposed analysis are demonstrated with a small MES case and a large one.

Based on the integrated jacket-support offshore wind turbine model of the National Renewable Energy Laboratory (NREL), the computational fluid dynamics (CFD) method is coupled with the wind turbine integrated analysis method to study the blade icing process and its influence on the overall dynamic performance of the wind turbine. First, the blade motion attitude calculated by the integrated analysis method is input into CFD. The discrete multiphase model and melting solidification model are used to simulate the icing growth of three-dimensional wind turbine blades. The k-ε turbulence model is used to calculate the aerodynamic performance before and after icing. Finally, the aerodynamic results after blade icing are returned to the integrated analysis method to analyze the influence of blade icing on the overall response of the wind turbine. The results show that the blade icing increases linearly along the blade span. The icing is mainly concentrated on the leading edge of the blade with the thickest ice accumulation at the tip. The lift coefficient decreases and the drag coefficient increases after icing. Blade icing will reduce the power of the whole machine, the torque, and the rotor speed. At the same time, it will lead to additional vibration response at the blade tip and tower top, and increase the wind speed required by the wind turbine to reach the rated power.

Purpose: Trimalleolar ankle fractures (TAFs) are common traumatic injuries. Studies have described postoperative clinical outcomes in relation to fracture morphology, but less is known about foot biomechanics, especially in patients treated for TAFs. The aim of this study was to analyze segmental foot mobility and joint coupling during the gait of patients after TAF treatment. Methods: Fifteen patients, surgically treated for TAFs, were recruited. The affected side was compared to their non-affected side, as well as to a healthy control subject. The Rizzoli foot model was used to quantify inter-segment joint angles and joint coupling. The stance phase was observed and divided into sub-phases. Patient-reported outcome measures were evaluated. Results: Patients treated for TAFs showed a reduced range of motion in the affected ankle during the loading response (3.8 ± 0.9) and pre-swing phase (12.7 ± 3.5) as compared to their non-affected sides (4.7 ± 1.1 and 16.1 ± 3.1) and the control subject. The dorsiflexion of the first metatarsophalangeal joint during the pre-swing phase was reduced (19.0 ± 6.5) when compared to the non-affected side (23.3 ± 8.7). The affected side's Chopart joint showed an increased range of motion during the mid-stance (1.3 ± 0.5 vs. 1.1 ± 0.6). Smaller joint coupling was observed on both the patient-affected and non-affected sides compared to the controls. Conclusion: This study indicates that the Chopart joint compensates for changes in the ankle segment after TAF osteosynthesis. Furthermore, reduced joint-coupling was observed. However, the minimal case numbers and study power limited the effect size of this study. Nevertheless, these new insights could help to elucidate foot biomechanics in these patients, adjusting rehabilitation programs, thereby lowering the risk of postoperative long-term complications. [ABSTRACT FROM AUTHOR]

Agricultural development is a necessary component of national development efforts to fight food crises and promote poverty reduction in many developing countries. However, many developing countries have fallen into a stalemate between modernization and development—modernized areas are less capable of driving regional development despite their abundant land and rich population. Striking a balance between agricultural technology and environmental protection is a key feature of sustainable land development. Based on the social–ecological resilience theory, this study takes Cambodia as an example and aims to establish a comprehensive evaluation index system to measure the agricultural production, regional road construction, and agricultural eco-environment in Cambodia. The coupled coordination model and gray relation analysis model are utilized to explore the interaction between agriculture, roads, and the agricultural eco-environment. The results show that (1) Cambodia has road environmental risks, and there is a need for rural labor migration in areas with higher levels of economic development. (2) The main agricultural production areas are faced with the dilemma of lagging infrastructure development, such as roads, and a huge potential for agricultural development. (3) In the plains areas, the growing population has caused tension between food security, fertilizer abuse, and deforestation, which intensified the disturbance of the agricultural ecological environment. In summary, based on their own developmental needs, developing countries at different stages of development can explore the interaction between agricultural production, infrastructure development, and the agricultural eco-environment in the process of agricultural development. This study attempts to provide a set of practical development policy implications for developing countries that are seeking to enhance the coupling relationship between agricultural production, infrastructure, and the agricultural eco-environment. [ABSTRACT FROM AUTHOR]

BACKGROUND: Discussing the research status and development trend of cortical bone trajectory screws and understanding the research direction and hotspots of cortical bone trajectory screws will help researchers grasp the latest information and development trends in this field. OBJECTIVE: To explore the global research status and future development trends of cortical bone trajectory screws. METHODS: English literature related to cortical bone trajectory screws published from January 1 2000 to October 28, 2021 was searched in the Web of Science core collection database. Bibliometric method was used to count and analyze the collected literature. VOS viewer software was used to perform visualized research on these articles to analyze the research hotspots and development trends of cortical bone trajectory screws. RESULTS AND CONCLUSION: (1) A total of 426 articles were included. The global research publication volume of cortical bone trajectory screws has increased year by year, with the most published articles in 2020, with a total of 64 articles published. Among them, the United States has the largest number of publications and has the largest contribution to the world, ranking No. 1 (172 papers). China has published 84 papers, ranking second. (2) WORLD NEUROSURGERY has the largest number of related papers at 33; the National Institutes of Health and the US Department of Health Human Services are the most funded. (3) MATSUKAWA K is the author with the most published articles, with 19 articles; YATO Y ranked second, with 14 articles published. (4) From the visual analysis of cortical bone trajectory screw research, the research in this field still has a lot of room for exploration, and the number of publications will continue to increase. The United States and Japan are leading in this field, followed by China. In recent years, the research direction has mainly focused on the surgical treatment of cortical bone trajectory screws. [ABSTRACT FROM AUTHOR]

The study aims to analyze the influence of complex service factors on ravelling resistance performance for large-void asphalt pavements by carrying out tests on environmental and vehicle factors, conducting ultraviolet aging, freeze–thaw cycles, as well as vehicle speed simulated tests with the Rotating Surface Abrasion Test, vehicle tests, and traffic volume tests, and by making a correlation analysis between the Cantabro Abrasion test and Rotating Surface Abrasion Test. The result shows that environmental factors significantly affect the ravelling resistance performance of drainage asphalt pavements. With the increase in the times of UV aging and freeze–thaw cycles, the ravelling loss rate of asphalt specimens shows a tendency to increase, and the combined test of UV aging and freeze–thaw cycles aggravated the ravelling damage of asphalt specimens. Meanwhile, vehicle factors have a significant attenuation effect on the ravelling resistance performance of drainage asphalt pavements. With the increase in the speed, pressure, and times of the Rotating Surface Abrasion, the ravelling loss rate of asphalt specimens shows a steady tendency to increase. Furthermore, there exists a good correlation between the Rotating Surface Abrasion speed, pressure, times, and the ravelling loss rate. Finally, the two test results of the Cantabro Abrasion test and Rotating Surface Abrasion test are consistent in their changes during single/composite factor analysis, confirming the feasibility of using the Rotating Surface Abrasion test index to characterize the change in the ravelling resistance performance of drainage asphalt pavements. [ABSTRACT FROM AUTHOR]

Anode hydrogen circulation system with purge valve has become one of the most effective ways for proton exchange membrane fuel cell (PEMFC) to alleviate performance degradation caused by nitrogen permeation and improve the hydrogen utilization rate. However, nonlinearity and multivariable coupling of the system make it difficult for PEMFC to achieve pressure and hydrogen supply synchronous tracking under complex operating conditions. To solve the problem, a novel nonlinear model predictive control scheme based on coupling analysis is proposed in this paper. Firstly, coupling characteristics of the hydrogen circulation system and the control pairing of the multivariable system are analyzed based on the relative gain array method. Then a novel control scheme based on an adaptive model predictive controller and a nonlinear model predictive controller is designed to keep the anode pressure stable and sufficient hydrogen supply, which use nonlinear observers to estimate the internal states online. Finally, the proposed controllers are implemented in control experiments of a 50 kW PEMFC anode hydrogen circulation system. The results demonstrate that the proposed control approach has great dynamic performance, anti-disturbance ability and can maintain a high hydrogen utilization rate under purge operation, current disturbance and uncertain intake pressure. • A PEMFC anode model with gas permeation and water transmission is proposed. • Multivariable coupling and control pairing of anode system are analyzed. • LPV-MPC and NMPC with state observers for anode pressure and flow regulation. • Dynamics of the recirculation system are improved under pressure fluctuations. • Trade-off between dynamic performance and efficiency of anode system is discussed. [ABSTRACT FROM AUTHOR]

Copyright of Large Electric Machine & Hydraulic Turbine is the property of Large Electric Machine & Hydraulic Turbine Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This research aims to analyze the contribution of univariate and relational citation analysis methods, applied to patents, for the identification and characterization of scientific-technological domains, in documents indexed in the Derwent Innovation Index database. The adopted method was patentometrics associated with bibliometrics, using joint analysis of the relational bibliometric citation methods: co-citation and bibliographic coupling. The corpus of the study is composed of 144 patent families. Through the bibliographic coupling, 5 theme clusters and researchers with well-defined thematic domains were observed. Employing co-citation, 23 clusters were identified, characterizing the epistemic domains related to technological currents in which stem cell inventors operate. Such results allowed us to prospect the scientific-technological scenario in this theme, which can illustrate some institutions' innovation potentials and explain who the actors at the forefront of such research are. It is proposed that applying this methodology allies to topic modeling techniques. [ABSTRACT FROM AUTHOR]

Submarine pipelines are widely adopted around the world for transporting oil and gas from offshore fields. They tend to be severely ruined by the extreme waves induced by the natural disaster, such as hurricanes and tsunamis. To maintain the safety and function integrity of the pipelines, porous media have been used to wrap them from the external loads by the submarine environment. The functions of the porous wrappers under the hydrodynamic impact remain to be uncovered before they are widely accepted by the industry. In this study, a numerical wave tank is established with the immersed boundary method as one of the computational fluid dynamics. The submarine pipelines and their porous wrappers are two-way-coupled in terms of displacement and pressure at their interfaces. The impact from the solitary waves, which approximately represent the extreme waves in the reality, on the pipelines with different configurations of the porous wrapper is investigated. The results present significant protective functions of the wrappers on the internal pipelines, transferring the impact forces from the pipelines to the wrappers. The protective effects tend to be enhanced by the porosity and thickness of the wrappers. The influence of the pipeline configurations and the marine environment are then analysed. As for the front pipeline, an increase in the gap leads to a slight increase in the horizontal forces on both the wrapper and the pipeline, but a significant increase in the vertical forces. As for the rear pipeline, because of the shield function of the front pipeline, the velocity within the gap space and the forces on the pipes are decreased with the decrease in the gap size. The complex flow fields around the pipelines with wrappers are also illuminated, implying that the protection function of the wrapper is enhanced by the wave height reduction.