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35 pages, 1129 KiB  
Article
Internal and External Cultivation to Drive Enterprises’ Green Transformation: Dual Perspectives of Vertical Supervision and Environmental Self-Discipline
by Huixiang Zeng, Yuyao Shao, Ning Ding, Limin Zheng and Jinling Zhao
Sustainability 2025, 17(15), 7062; https://doi.org/10.3390/su17157062 - 4 Aug 2025
Viewed by 227
Abstract
Central Environmental Protection Inspection (CEPI) is a major step in China’s environmental vertical supervision reform. With the multi-period Difference-in-Differences method, we assess the impact of CEPI on enterprise green transformation. In addition, we further explore the impact of enterprise environmental self-discipline. The results [...] Read more.
Central Environmental Protection Inspection (CEPI) is a major step in China’s environmental vertical supervision reform. With the multi-period Difference-in-Differences method, we assess the impact of CEPI on enterprise green transformation. In addition, we further explore the impact of enterprise environmental self-discipline. The results show that CEPI significantly promotes enterprise green transformation, and this effect on governance is further strengthened by environmental self-discipline. The synergistic governance effect of compound environmental regulation is pronounced, particularly in enterprises lacking government–enterprise relationships and in areas covered by CEPI “look back” initiatives and where local governments rigorously enforce environmental laws. The mechanism analysis reveals that CEPI mainly promotes enterprise green transformation by improving executive green cognition, boosting investment in environmental protection, and enhancing green innovation efficiency. This study provides a fresh perspective on analyzing the governance impact of CEPI and provides valuable insights for improving multi-collaborative environmental governance systems. Full article
(This article belongs to the Section Economic and Business Aspects of Sustainability)
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25 pages, 5841 KiB  
Article
Creating Micro-Habitat in a Pool-Weir Fish Pass with Flexible Hydraulic Elements: Insights from Field Experiments
by Mehmet Salih Turker and Serhat Kucukali
Water 2025, 17(15), 2294; https://doi.org/10.3390/w17152294 - 1 Aug 2025
Viewed by 193
Abstract
The placement of hydraulic elements in existing pool-type fishways to make them more suitable for Cyprinid fish is an issue of increasing interest in fishway research. Hydrodynamic characteristics and fish behavior at the representative pool of the fishway with bottom orifices and notches [...] Read more.
The placement of hydraulic elements in existing pool-type fishways to make them more suitable for Cyprinid fish is an issue of increasing interest in fishway research. Hydrodynamic characteristics and fish behavior at the representative pool of the fishway with bottom orifices and notches were assessed at the Dagdelen hydropower plant in the Ceyhan River Basin, Türkiye. Three-dimensional velocity measurements were taken in the pool of the fishway using an Acoustic Doppler velocimeter. The measurements were taken with and without a brush block at two different vertical distances from the bottom, which were below and above the level of bristles tips. A computational fluid dynamics (CFD) analysis was conducted for the studied fishway. The numerical model utilized Large Eddy Simulation (LES) combined with the Darcy–Forchheimer law, wherein brush blocks were represented as homogenous porous media. Our results revealed that the relative submergence of bristles in the brush block plays a very important role in velocity and Reynolds shear stress (RSS) distributions. After the placement of the submerged brush block, flow velocity and the lateral RSS component were reduced, and a resting area was created behind the brush block below the bristles’ tips. Fish movements in the pool were recorded by underwater cameras under real-time operation conditions. The heatmap analysis, which is a 2-dimensional fish spatial presence visualization technique for a specific time period, showed that Capoeta damascina avoided the areas with high turbulent fluctuations during the tests, and 61.5% of the fish presence intensity was found to be in the low Reynolds shear regions in the pool. This provides a clear case for the real-world ecological benefits of retrofitting existing pool-weir fishways with such flexible hydraulic elements. Full article
(This article belongs to the Section Hydraulics and Hydrodynamics)
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19 pages, 3405 KiB  
Article
Study on Hydrological–Meteorological Response in the Upper Yellow River Based on 100-Year Series Reconstruction
by Xiaohui He, Xiaoyu He, Yajun Gao and Fanchao Li
Water 2025, 17(15), 2223; https://doi.org/10.3390/w17152223 - 25 Jul 2025
Viewed by 402
Abstract
Precipitation, as a key input in the water cycle, directly influences the formation and change process of runoff. Meanwhile, the return runoff intuitively reflects the available quantity of water resources in a river basin. An in-depth analysis of the evolution laws and response [...] Read more.
Precipitation, as a key input in the water cycle, directly influences the formation and change process of runoff. Meanwhile, the return runoff intuitively reflects the available quantity of water resources in a river basin. An in-depth analysis of the evolution laws and response relationships between precipitation and return runoff over a long time scale serves as an important support for exploring the evolution of hydrometeorological conditions and provides an accurate basis for the scientific planning and management of water resources. Taking Lanzhou Station on the upper Yellow River as a typical case, this study proposes the VSSL (LSTM Fusion Method Optimized by SSA with VMD Decomposition) deep learning precipitation element series extension method and the SSVR (SVR Fusion Method Optimized by SSA) machine learning runoff element series extension method. These methods achieve a reasonable extension of the missing data and construct 100-year precipitation and return runoff series from 1921 to 2020. The research results showed that the performance of machine learning and deep learning methods in the precipitation and return runoff test sets is better than that of traditional statistical methods, and the fitting effect of return runoff is better than that of precipitation. The 100-year precipitation and return runoff series of Lanzhou Station from 1921 to 2020 show a non-significant upward trend at a rate of 0.26 mm/a and 0.42 × 108 m3/a, respectively. There is no significant mutation point in precipitation, while the mutation point of return runoff occurred in 1991. The 100-year precipitation series of Lanzhou Station has four time-scale alternations of dry and wet periods, with main periods of 60 years, 20 years, 12 years, and 6 years, respectively. The 100-year return runoff series has three time-scale alternations of dry and wet periods, with main periods of 60 years, 34 years, and 26 years, respectively. During the period from 1940 to 2000, an approximately 50-year cycle, precipitation and runoff not only have strong common-change energy and significant interaction, but also have a fixed phase difference. Precipitation changes precede runoff, and runoff responds after a fixed time interval. Full article
(This article belongs to the Section Water and Climate Change)
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25 pages, 3279 KiB  
Review
Current State of Development of Demand-Driven Biogas Plants in Poland
by Aleksandra Łukomska, Kamil Witaszek and Jacek Dach
Processes 2025, 13(8), 2369; https://doi.org/10.3390/pr13082369 - 25 Jul 2025
Viewed by 474
Abstract
Renewable energy sources (RES) are the foundation of the ongoing energy transition in Poland and worldwide. However, increased use of RES has brought several challenges, as most of these sources are dependent on weather conditions. The instability and lack of control over electricity [...] Read more.
Renewable energy sources (RES) are the foundation of the ongoing energy transition in Poland and worldwide. However, increased use of RES has brought several challenges, as most of these sources are dependent on weather conditions. The instability and lack of control over electricity production lead to both overloads and power shortages in transmission and distribution networks. A significant advantage of biogas plants over sources such as photovoltaics or wind turbines is their ability to control electricity generation and align it with actual demand. Biogas produced during fermentation can be temporarily stored in a biogas tank above the digester and later used in an enlarged CHP unit to generate electricity and heat during peak demand periods. While demand-driven biogas plants operate similarly to traditional installations, their development requires navigating regulatory and administrative procedures, particularly those related to the grid connection of the generated electricity. In Poland, it has only recently become possible to obtain grid connection conditions for such installations, following the adoption of the Act of 28 July 2023, which amended the Energy Law and certain other acts. However, the biogas sector still faces challenges, particularly the need for effective incentive mechanisms and the removal of regulatory and economic barriers, especially given its estimated potential of up to 7.4 GW. Full article
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23 pages, 406 KiB  
Article
Periodically Kicked Rotator with Power-Law Memory: Exact Solution and Discrete Maps
by Vasily E. Tarasov
Fractal Fract. 2025, 9(7), 472; https://doi.org/10.3390/fractalfract9070472 - 21 Jul 2025
Viewed by 395
Abstract
This article discusses the transformation of a continuous-time model of the fractional system into a discrete-time model of the fractional system. For the continuous-time model, the exact solution of the nonlinear equation with fractional derivatives (FDs) that has the form of the damped [...] Read more.
This article discusses the transformation of a continuous-time model of the fractional system into a discrete-time model of the fractional system. For the continuous-time model, the exact solution of the nonlinear equation with fractional derivatives (FDs) that has the form of the damped rotator type with power non-locality in time is obtained.This equation with two FDs and periodic kicks is solved in the general case for the arbitrary orders of FDs without any approximations. A three-stage method for solving a nonlinear equation with two FDs and deriving discrete maps with memory (DMMs) is proposed. The exact solutions of the nonlinear equation with two FDs are obtained for arbitrary values of the orders of these derivatives. In this article, the orders of two FDs are not related to each other, unlike in previous works. The exact solution of nonlinear equation with two FDs of different orders and periodic kicks are proposed. Using this exact solution, we derive DMMs that describe a kicked damped rotator with power-law non-localities in time. For the discrete-time model, these damped DMMs are described by the exact solution of nonlinear equations with FDs at discrete time points as the functions of all past discrete moments of time. An example of the application, the exact solution and DMMs are proposed for the economic growth model with two-parameter power-law memory and price kicks. It should be emphasized that the manuscript proposes exact analytical solutions to nonlinear equations with FDs, which are derived without any approximations. Therefore, it does not require any numerical proofs, justifications, or numerical validation. The proposed method gives exact analytical solutions, where approximations are not used at all. Full article
22 pages, 3439 KiB  
Article
Metabolomics Analysis Reveals the Influence Mechanism of Different Growth Years on the Growth, Metabolism and Accumulation of Medicinal Components of Bupleurum scorzonerifolium Willd. (Apiaceae)
by Jialin Sun, Jianhao Wu, Weinan Li, Xiubo Liu and Wei Ma
Biology 2025, 14(7), 864; https://doi.org/10.3390/biology14070864 - 16 Jul 2025
Viewed by 230
Abstract
Bupleurum scorzonerifolium Willd. is a perennial herbaceous plant of the genus Bupleurum in the Apiaceae family. Also known as red Bupleurum, it is mainly distributed in Northeast China, North China and other regions and is a commonly used medicinal plant. It is [...] Read more.
Bupleurum scorzonerifolium Willd. is a perennial herbaceous plant of the genus Bupleurum in the Apiaceae family. Also known as red Bupleurum, it is mainly distributed in Northeast China, North China and other regions and is a commonly used medicinal plant. It is difficult for the wild plant resources of Bupleurum scorzonerifolium Willd. to meet the market demand. In artificial cultivation, there are problems such as a low yield per plant, low quality, weakened stress resistance and variety degradation. The contents of bioactive components and metabolites in traditional Chinese medicinal materials vary significantly across different growth years. The growth duration directly impacts their quality and clinical efficacy. Therefore, determining the optimal growth period is one of the crucial factors in ensuring the quality of traditional Chinese medicinal materials. In this study, Gas Chromatography–Mass Spectrometry (GC-MS) and High-performance liquid chromatography (HPLC) were comprehensively applied to analyze the metabolically differential substances in different parts of Bupleurum scorzonerifolium Willd. By comparing the compositions and content differences of chemical components in different growth years and different parts, the chemical components with significant differences were accurately screened out. In order to further explore the dynamic change characteristics and internal laws of metabolites, a metabolic network was constructed for a visual analysis and, finally, to see the optimal growth years of Bupleurum scorzonerifolium Willd. This result showed that with the accumulation of the growth cycle, the height, root width, fresh mass and saikosaponins content of Bupleurum scorzonerifolium Willd. increased year by year. Except for sodium and calcium elements in the main shoot, the other elements were significantly reduced. In addition, 59 primary metabolites were identified by GC-MS, with the accumulation of the growth cycle, the contents of organic acids, sugars, alcohols and amino acids gradually decreased, while the contents of alkyl, glycosides and other substances gradually increased. There were 53 positive correlations and 18 negative correlations in the triennial Bupleurum scorzonerifolium Willd. grid, all of which were positively correlated with saikosaponins. Therefore, the triennial Bupleurum scorzonerifolium Willd. was considered to be the suitable growth year. It not only provided a new idea and method for the quality evaluation of Bupleurum scorzonerifolium Willd., but also provided a scientific basis for the quality control of Chinese herbs. Full article
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16 pages, 516 KiB  
Article
The Rebuilding of the Kaʻba During the Period of Sulṭān Murād IV in the Context of the ʻUlamāʼ-Umarāʼ Discussions
by Abdullah Çakmak
Religions 2025, 16(7), 915; https://doi.org/10.3390/rel16070915 - 16 Jul 2025
Viewed by 416
Abstract
The last stop on the Muslim pilgrimage is the Kaʻba. Like all other holy and religious places, the Kaʻba has survived due to the repairs it has undergone since its construction. However, the Kaʻba has been rebuilt at times when it was destroyed [...] Read more.
The last stop on the Muslim pilgrimage is the Kaʻba. Like all other holy and religious places, the Kaʻba has survived due to the repairs it has undergone since its construction. However, the Kaʻba has been rebuilt at times when it was destroyed for various reasons. Since the interruption of the pilgrimage would undermine the legitimacy of the caliph, Muslims attached great importance to rebuilding the Kaʻba in such cases. The Kaʻba was last rebuilt by the Ottoman Sulṭān Murād IV after the flood of 1039/1630. However, the rebuilding process has not been without its controversies. Although the Ottoman Empire attempted to rebuild the Kaʻba out of necessity, some scholars objected to this initiative. Ibn ʻAllān, one of the leading Shafiʻi muftis of Mecca, followed the rebuilding work day by day and did not hesitate to intervene when necessary. Riḍwān Agha, who carried out the rebuilding of the Kaʻba, was able to overcome Ibn ʻAllān’s objections with fatwas from the muftis of the four sects (four Sunni schools of law) and thus completed the building work. After the Kaʻba was rebuilt, Turkish works on its history began to be produced. In this way, the public was informed that the Kaʻba could be rebuilt if necessary, and attempts were made to anticipate and prevent any potential reactions. This study aims to contribute to the history of the Kaʻba by analysing its rebuilding after the flood of 1039/1630 through debates between scholars (ʻulamāʼ) and administrators (umarāʼ) during this period. Access to the details of this issue from the works of the ʻulamāʼ who witnessed the rebuilding makes this paper unique. Full article
(This article belongs to the Special Issue Pilgrimage: Diversity, Past and Present of Sacred Routes)
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25 pages, 953 KiB  
Article
How Changing Portraits and Opinions of “Pit Bulls” Undermined Breed-Specific Legislation in the United States
by Michael Tesler and Mary McThomas
Animals 2025, 15(14), 2083; https://doi.org/10.3390/ani15142083 - 15 Jul 2025
Viewed by 570
Abstract
Scholars and journalists typically trace the diffusion of breed-specific legislation (BSL) in the U.S. to the surge in negative media portraits of pit bull-type dogs (PBTDs) during the late twentieth century. Yet, while news coverage still portrays these dogs unfavorably, we document a [...] Read more.
Scholars and journalists typically trace the diffusion of breed-specific legislation (BSL) in the U.S. to the surge in negative media portraits of pit bull-type dogs (PBTDs) during the late twentieth century. Yet, while news coverage still portrays these dogs unfavorably, we document a sharp rise in countervailing sources of “pit bull positivity” over the past two decades. Drawing on insights from the respective social science research on changes in attitudes and public policy, we argue that this influx of positivity should powerfully impact opinions and policies towards PBTDs. Our data and analyses consistently support that argument. We analyze two different series of repeated cross-sectional surveys to show that public support for “pit bulls” grew considerably from 2014 to 2024. We also show that voters’ support for ballot measures overturning local “pit bull bans” increased substantially during that same ten-year period. Finally, our analysis of the frames and narratives deployed in recent state and local policy debates shows how this growing pit bull positivity has helped overturn over 300 discriminatory laws against these dogs since 2012. We conclude with a discussion of how shifts in portraits and opinions of PBTDs will likely continue eroding breed-specific legislation going forward. Full article
(This article belongs to the Special Issue Animal Law and Policy Across the Globe in 2025)
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21 pages, 10296 KiB  
Article
Spatiotemporal Mechanical Effects of Framework–Slope Systems Under Frost Heave Conditions
by Wendong Li, Xiaoqiang Hou, Jixian Ren and Chaoyang Wu
Appl. Sci. 2025, 15(14), 7877; https://doi.org/10.3390/app15147877 - 15 Jul 2025
Viewed by 280
Abstract
To investigate the slope instability caused by differential frost heaving mechanisms from the slope crest to the toe during frost heave processes, this study takes a typical silty clay slope in Xinjiang, China, as the research object. Through indoor triaxial consolidated undrained shear [...] Read more.
To investigate the slope instability caused by differential frost heaving mechanisms from the slope crest to the toe during frost heave processes, this study takes a typical silty clay slope in Xinjiang, China, as the research object. Through indoor triaxial consolidated undrained shear tests, eight sets of natural and frost-heaved specimens were prepared under confining pressure conditions ranging from 100 to 400 kPa. The geotechnical parameters of the soil in both natural and frost-heaved states were obtained, and a spatiotemporal thermo-hydro-mechanical coupled numerical model was established to reveal the dynamic evolution law of anchor rod axial forces and the frost heave response mechanism between the frame and slope soil. The analytical results indicate that (1) the frost heave process is influenced by slope boundaries, resulting in distinct spatial variations in the temperature field response across the slope surface—namely pronounced responses at the crest and toe but a weaker response in the mid-slope. (2) Under the coupled drive of the water potential gradient and gravitational potential gradient, the ice content in the toe area increases significantly, and the horizontal frost heave force exhibits exponential growth, reaching its peak value of 92 kPa at the toe in February. (3) During soil freezing, the reverse stress field generated by soil arching shows consistent temporal variation trends with the temperature field. Along the height of the soil arch, the intensity of the reverse frost heave force field displays a nonlinear distribution characteristic of initial strengthening followed by attenuation. (4) By analyzing the changes in anchor rod axial forces during frost heaving, it was found that axial forces during the frost heave period are approximately 1.3 times those under natural conditions, confirming the frost heave period as the most critical condition for frame anchor design. Furthermore, through comparative analysis with 12 months of on-site anchor rod axial force monitoring data, the reliability and accuracy of the numerical simulation model were validated. These research outcomes provide a theoretical basis for the design of frame anchor support systems in seasonally frozen regions. Full article
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21 pages, 3134 KiB  
Article
Allometric Growth and Carbon Sequestration of Young Kandelia obovata Plantations in a Constructed Urban Costal Wetland in Haicang Bay, Southeast China
by Jue Zheng, Lumin Sun, Lingxuan Zhong, Yizhou Yuan, Xiaoyu Wang, Yunzhen Wu, Changyi Lu, Shufang Xue and Yixuan Song
Forests 2025, 16(7), 1126; https://doi.org/10.3390/f16071126 - 8 Jul 2025
Viewed by 444
Abstract
The focus of this study was on young populations of Kandelia obovata within a constructed coastal wetland in Haicang Bay, Xiamen, Southeast China. The objective was to systematically examine their allometric growth characteristics and carbon sequestration potential over an 8-year monitoring period (2016–2024). [...] Read more.
The focus of this study was on young populations of Kandelia obovata within a constructed coastal wetland in Haicang Bay, Xiamen, Southeast China. The objective was to systematically examine their allometric growth characteristics and carbon sequestration potential over an 8-year monitoring period (2016–2024). Allometric equations were developed to estimate biomass, and the spatiotemporal variation in both plant and soil carbon stocks was estimated. There was a significant increase in total biomass per tree, from 120 ± 17 g at initial planting to 4.37 ± 0.59 kg after 8 years (p < 0.001), with aboveground biomass accounting for the largest part (72.2% ± 7.3%). The power law equation with D2H as an independent variable yielded the highest predictive accuracy for total biomass (R2 = 0.957). Vegetation carbon storage exhibited an annual growth rate of 4.2 ± 0.8 Mg C·ha−1·yr−1. In contrast, sediment carbon stocks did not show a significant increase throughout the experimental period, although long-term accumulation was observed. The restoration of mangroves in urban coastal constructed wetlands is an effective measure to sequester carbon, achieving a carbon accumulation rate of 21.8 Mg CO2eq·ha−1·yr−1. This rate surpasses that of traditional restoration methods, underscoring the pivotal role of interventions in augmenting blue carbon sinks. This study provides essential parameters for allometric modeling and carbon accounting in urban mangrove afforestation strategies, facilitating optimized restoration management and low-carbon strategies. Full article
(This article belongs to the Section Forest Ecology and Management)
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11 pages, 4942 KiB  
Field Guide
Paleopathology in Bone Material from the Anthropology Laboratory of the University of Granada
by Miguel C. Botella, Meriem Khaled and José Gijón
Encyclopedia 2025, 5(3), 99; https://doi.org/10.3390/encyclopedia5030099 - 7 Jul 2025
Viewed by 313
Abstract
The Field Guide “Paleopathology Collection at the University of Granada” includes one of the most important collections of human bone remains that present anomalies or specific characteristics that can be used to determine the existence of diseases, accidents or malformations in each subject’s [...] Read more.
The Field Guide “Paleopathology Collection at the University of Granada” includes one of the most important collections of human bone remains that present anomalies or specific characteristics that can be used to determine the existence of diseases, accidents or malformations in each subject’s life, as well as the probable cause of death. The collection consists of several thousand skeletons or parts of them. It is located at the Faculty of Medicine of the University of Granada and has been created and managed by Professor Miguel C. Botella López, founder and director of the Anthropology Laboratory of the University of Granada, between 1971 and 2024. Professor Botella is the author of the diagnoses made for each specimen from different geographical areas of Spain in a time period ranging from the Neolithic to the present day. The collection is of special interest to students and professionals in medicine, archaeology, criminology or law. Full article
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15 pages, 576 KiB  
Review
Police Fitness: An International Perspective on Current and Future Challenges
by Robin Orr, Elisa F. D. Canetti, Suzanne Gough, Kirstin Macdonald, Joe Dulla, Robert G. Lockie, J. Jay Dawes, Sam D. Blacker, Gemma S. Milligan and Ben Schram
Sports 2025, 13(7), 219; https://doi.org/10.3390/sports13070219 - 7 Jul 2025
Viewed by 1113
Abstract
Poor officer fitness can lead to decreased occupational task performance, injuries, increased absenteeism, and a variety of negative health sequalae further adding to the challenges of staffing law enforcement agencies. Optimizing the physical fitness for both serving officers and new recruits is critical [...] Read more.
Poor officer fitness can lead to decreased occupational task performance, injuries, increased absenteeism, and a variety of negative health sequalae further adding to the challenges of staffing law enforcement agencies. Optimizing the physical fitness for both serving officers and new recruits is critical as their loss is, and will increasingly be, difficult to replace. However, maintaining and recruiting a physically fit workforce faces several challenges. For serving officers, shiftwork is known to decrease motivation to exercise and negatively impact sleep and diet. Additional factors impacting their fitness includes age-related declines in fitness, increasing obesity, long periods of sedentarism, and negative COVID-19 effects. Concurrently, recruiting physically fit recruits is challenged by declining levels of fitness, reduced physical activity, and increasing obesity in community youth. Ability-based training (ABT), individualizing physical conditioning training based on the existing fitness levels of individuals within a group, offers a potential solution for delivering physical conditioning to groups of applicants, recruits, and officers with a range of physical fitness capabilities. Law enforcement agencies should consider implementing ABT during academy training and ongoing fitness maintenance to minimize injury risk and optimize task performance. Full article
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18 pages, 1717 KiB  
Article
Symmetries, Conservation Laws, and Exact Solutions of a Potential Kadomtsev–Petviashvili Equation with Power-Law Nonlinearity
by Dimpho Millicent Mothibi
Symmetry 2025, 17(7), 1053; https://doi.org/10.3390/sym17071053 - 3 Jul 2025
Viewed by 267
Abstract
This study investigates the potential Kadomtsev–Petviashvili equation incorporating a power-type nonlinearity (PKPp), a model that features prominently in various nonlinear phenomena encountered in physics and applied mathematics. A complete Noether symmetry classification of the PKPp equation is conducted, revealing four distinct scenarios based [...] Read more.
This study investigates the potential Kadomtsev–Petviashvili equation incorporating a power-type nonlinearity (PKPp), a model that features prominently in various nonlinear phenomena encountered in physics and applied mathematics. A complete Noether symmetry classification of the PKPp equation is conducted, revealing four distinct scenarios based on different values of the exponent p, namely, the general case where p1,1,2, and three special cases where p=1,p=1, and p=2. Corresponding to each case, conservation laws are derived through a second-order Lagrangian framework. Furthermore, Lie group analysis is employed to reduce the nonlinear partial differential Equation (NLPDE) to ordinary differential Equations (ODEs), thereby enabling the effective application of the Kudryashov method and direct integration techniques to construct exact solutions. In particular, exact solutions of of the considered nonlinear partial differential equation are obtained for the cases p=1 and p=2, illustrating the practical implementation of the proposed approach. The solutions obtained include solitary wave, periodic, and rational-type solutions. These results enhance the analytical understanding of the PKPp equation and contribute to the broader theory of nonlinear dispersive equations. Full article
(This article belongs to the Special Issue Symmetries in Differential Equations and Application—2nd Edition)
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22 pages, 48463 KiB  
Article
Study on the Evolution of Overlying Strata Fractures and Gas Control Technology of High Gas-Drainage Roadways Under Gob-Side Entry Retaining with Roadside Filling
by Yunfei Yang, Zetian Li, Anxiu Liu, Hongwei Liu, Zhangyang Li, Hongguang Guo and Zhigang Li
Appl. Sci. 2025, 15(13), 7445; https://doi.org/10.3390/app15137445 - 2 Jul 2025
Viewed by 288
Abstract
In order to examine the fracture development law of overlying strata in goafs and to reasonably lay out a high gas-drainage roadway under gob-side entry retaining with roadside filling, the 91–105 working face of the Wangzhuang Coal Mine was selected as the engineering [...] Read more.
In order to examine the fracture development law of overlying strata in goafs and to reasonably lay out a high gas-drainage roadway under gob-side entry retaining with roadside filling, the 91–105 working face of the Wangzhuang Coal Mine was selected as the engineering case study. The failure laws and fracture development characteristics of the overlying strata in both the strike and dip directions using gob-side entry retaining and roadside filling were studied through rock mechanic tests and PFC numerical simulations. The optimal layout of the high gas-drainage roadway was determined through theoretical analysis and coupled Fluent–PFC numerical simulations, and on-site monitoring was conducted to evaluate the extraction effects. The results indicate that the first weighting interval of the 91–105 working face was 40 m, while the periodic weighting interval was approximately 14 m. The height of the falling zone was 14.4 m, and the height of the gas-conducting fracture zone was 40.7 m. In the dip direction, compared with coal pillar retaining, gob-side entry retaining with roadside filling formed an inverted trapezoid secondary breaking zone above the retaining roadway. Using this method, the span of the separation zone increased to 30 m, and the collapse angle decreased to 52°, resulting in a shift in the separation zone—the primary space for gas migration—toward the goaf. It was determined that the optimal location of the high gas-drainage roadway was 28 m above the coal roof and 30 m horizontally from the return air roadway. Compared with the 8105 working face, this position was 10 m closer toward the goaf. On-site gas extraction monitoring data indicate that, at this optimized position, the gas concentration in the high gas-drainage roadway increased by 22%, and the net gas flow increased by 18%. Full article
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19 pages, 4066 KiB  
Article
Mechanical Response and Fatigue Life Analysis of Asphalt Pavements Under Temperature-Load Coupling Conditions
by Zhenzheng Liu, Le Zhang, Yuan Gao, Yanying Dong, Yuhang Liu and Bo Li
Appl. Sci. 2025, 15(13), 7441; https://doi.org/10.3390/app15137441 - 2 Jul 2025
Viewed by 213
Abstract
The effects of heavy traffic and complex natural environmental conditions have made the problem of the inadequate life expectancy of asphalt pavements increasingly pronounced. In this study, finite-element software was used to establish the three-dimensional analytical model of temperature-load coupling under different axial [...] Read more.
The effects of heavy traffic and complex natural environmental conditions have made the problem of the inadequate life expectancy of asphalt pavements increasingly pronounced. In this study, finite-element software was used to establish the three-dimensional analytical model of temperature-load coupling under different axial loads and calculate the distribution law of temperature-load coupling stress under the most unfavorable loading conditions. By comparing temperature and coupled stresses at different depths, the extent to which combined stress changes due to environmental factors affect different depths was determined. Finally, the fatigue life patterns of asphalt pavements under different seasons and axle loads were analyzed. The results showed that the temperature-load coupling stress varied periodically under different axial loads. Among them, the temperature stress had less influence on the coupling stress in spring and fall and more influence in winter. As the depth increases, the coupling stresses and their range of influence gradually decrease. Also, the farther away from the wheel load position, the smaller the traveling load disturbance and the closer the coupling stresses were to the temperature stresses. Under the most unfavorable loading conditions, the change rule of the degree of influence of environmental effects along the depth direction showed that the winter gradually decreased, the spring and fall seasons for the first time decreased and then increased, and the minimum influence on the road surface was at 9 cm. Overall, the degree of influence of environmental action at different axial loads was 70.53%, 41.90%, 27.13%, and 23.77% along the depth direction. Full article
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