An upper estimate of the new curvature entropy is provided,via the integral inequality of a concave function.For two origin-symmetric convex bodies in R^(n),this bound is sharper than the log-Minkowski inequality of c...An upper estimate of the new curvature entropy is provided,via the integral inequality of a concave function.For two origin-symmetric convex bodies in R^(n),this bound is sharper than the log-Minkowski inequality of curvature entropy.As its application,a novel proof of the log-Minkowski inequality of curvature entropy in the plane is given.展开更多
Energy poverty in developing countries is a critical issue characterized by the lack of access to modern energy services,such as electricity and clean cooking facilities,as marked in SDG 7.This study explores the corr...Energy poverty in developing countries is a critical issue characterized by the lack of access to modern energy services,such as electricity and clean cooking facilities,as marked in SDG 7.This study explores the correlations between energy poverty,energy intensity,resource abundance,and income inequality,as these factors have been theorized to play important roles in influencing energy poverty in developing countries.By observing that the dataset is heterogeneous across the countries and over the time frame,we use the Method of Moments Quantile Regression(MMQR)to analyze our developing countries’data from 2000 to 2019.Our findings indicate that energy intensity is a significant factor influencing energy poverty,suggesting that higher energy consumption relative to the sample countries can exacerbate this issue.Additionally,we observe that income inequality within the sample countries is a critical determinant of energy poverty levels,highlighting the dynamics between economic disparity and access to energy resources.Interestingly,our study reveals that resource abundance acts as a blessing rather than a curse in terms of energy poverty,implying that countries rich in natural resources may have better opportunities to combat energy deprivation.Finally,we emphasize the vital role of financial markets in addressing energy poverty on a global scale,suggesting that robust financial systems can facilitate investments and innovations aimed at improving energy access for vulnerable populations.The results from the robustness analysis support the empirical results obtained from the main estimation.The empirical findings of the present study advance important comprehensions for policymakers to adopt energy policies that address the complex challenges of energy poverty and promote inclusive energy access.展开更多
In this paper,we construct a power type functional which is the approximation functional of the Singular Trudinger-Moser functional.Moreover,we obtain the concentration level of the functional and show it converges to...In this paper,we construct a power type functional which is the approximation functional of the Singular Trudinger-Moser functional.Moreover,we obtain the concentration level of the functional and show it converges to the concentration level of singular Trudinger-Moser functional on the unit ball.展开更多
An evolution inequality of Sobolev type involving a nonlinear convolution term is considered.By using the nonlinear capacity method and the contradiction argument,the non-existence of the nontrivial local weak solutio...An evolution inequality of Sobolev type involving a nonlinear convolution term is considered.By using the nonlinear capacity method and the contradiction argument,the non-existence of the nontrivial local weak solution is proved.展开更多
The purpose of this article is to introduce a new method with a self-adaptive stepsize for approximating a common solution of monotone inclusion problems and variational inequality problems in reflexive Banach spaces....The purpose of this article is to introduce a new method with a self-adaptive stepsize for approximating a common solution of monotone inclusion problems and variational inequality problems in reflexive Banach spaces.The strong convergence result for our method is established under some standard assumptions without any requirement of the knowledge of the Lipschitz constant of the mapping.Several numerical experiments are provided to verify the advantages and efficiency of proposed algorithms.展开更多
The purpose of this paper is to study some famous inequalities in Euclidean space.We are able to reveal an elegant relation between the famous Selberg inequality and Bessel inequality in Euclidean space.
This study examines the impact of artificial intelligence(AI)on carbon inequality(CI)in 67 countries from 1995 to 2019.The results suggest that(i)AI significantly amplifies CI both between and within countries due to ...This study examines the impact of artificial intelligence(AI)on carbon inequality(CI)in 67 countries from 1995 to 2019.The results suggest that(i)AI significantly amplifies CI both between and within countries due to its energy requirements and uneven deployment;(ii)trade openness and global value chain(GVC)positioning mitigate AI’s effect on inter-country CI,while robust governance—marked by larger government size and institutional transparency—curtails intra-country disparities;(iii)specific thresholds(trade openness>4.74,GVC position>−1.07,government size>2.90,transparency>−0.22)shift the impact of AI from exacerbating to reducing CI.The adverse effects of AI can be reversed through enhanced trade,GVC integration,and strong governance.Key policy implications:Policymakers must prioritize exceeding these thresholds to leverage AI for sustainable and equitable outcomes.This requires(a)promoting trade liberalization to spread the benefits of AI globally,reducing inter-country CI;(b)strengthening GVC participation to offset the carbon-intensive use of AI;(c)building government capacity and transparency to ensure fair adoption of AI domestically;and(d)embedding these strategies in climate policies to align AI with the long-term goals of environmental justice and the SDGs,particularly climate action(SDG 13)and reducing inequalities(SDG 10).展开更多
Since 2000,China's investment in Africa has grown rapidly,following a steady upward trajectory.However,this influx of Chinese capital has sparked both economic and political controversies.By integrating multi-sour...Since 2000,China's investment in Africa has grown rapidly,following a steady upward trajectory.However,this influx of Chinese capital has sparked both economic and political controversies.By integrating multi-source data—from micro-level individual projects to national statistics—this study examines the impact of Chinese investment on African economic development between 2000 and 2022.The results reveal a significant positive correlation between Chinese investment and economic growth across different scales,with investment-intensive regions achieving stronger economic outcomes.The DID analysis indicates that the Belt and Road Initiative has contributed positively to Africa's economic development.Both static and dynamic panel models confirm that Chinese investment significantly stimulates growth,exhibiting notable lag effects.Furthermore,β-convergence models demonstrate that Chinese investment fosters economic convergence among African countries.Regarding regional inequality,the findings suggest that Chinese investment helps to narrow disparities across Africa,promoting a more balanced economic landscape.Overall,this research underscores the constructive role of China's investment in fostering economic growth and reducing inequality within the African context.展开更多
In this paper,we establish a stability estimate for the isoperimetric inequality of horospherically convex domains in hyperbolic plane.This estimate involves a relationship between the Hausdorff distance to a geodesic...In this paper,we establish a stability estimate for the isoperimetric inequality of horospherically convex domains in hyperbolic plane.This estimate involves a relationship between the Hausdorff distance to a geodesic ball and the deficit in the isoperimetric inequality,where the coefficient of the deficit is a universal constant.展开更多
Three-dimensional(3D)urban structures play a critical role in informing climate mitigation strategies aimed at the built environment and facilitating sustainable urban development.Regrettably,there exists a significan...Three-dimensional(3D)urban structures play a critical role in informing climate mitigation strategies aimed at the built environment and facilitating sustainable urban development.Regrettably,there exists a significant gap in detailed and consistent data on 3D building space structures with global coverage due to the challenges inherent in the data collection and model calibration processes.In this study,we constructed a global urban structure(GUS-3D)dataset,including building volume,height,and footprint information,at a 500 m spatial resolution using extensive satellite observation products and numerous reference building samples.Our analysis indicated that the total volume of buildings worldwide in2015 exceeded 1×10^(12)m^(3).Over the 1985 to 2015 period,we observed a slight increase in the magnitude of 3D building volume growth(i.e.,it increased from 166.02 km3 during the 1985–2000 period to 175.08km3 during the 2000–2015 period),while the expansion magnitudes of the two-dimensional(2D)building footprint(22.51×10^(3) vs 13.29×10^(3)km^(2))and urban extent(157×10^(3) vs 133.8×10^(3)km^(2))notably decreased.This trend highlights the significant increase in intensive vertical utilization of urban land.Furthermore,we identified significant heterogeneity in building space provision and inequality across cities worldwide.This inequality is particularly pronounced in many populous Asian cities,which has been overlooked in previous studies on economic inequality.The GUS-3D dataset shows great potential to deepen our understanding of the urban environment and creates new horizons for numerous 3D urban studies.展开更多
In this paper, we investigate the effect of exceptional points(EPs) on the violation of Leggett–Garg inequality(LGI) and no-signaling-in-time(NSIT) conditions and compare the different effects between the Hamiltonian...In this paper, we investigate the effect of exceptional points(EPs) on the violation of Leggett–Garg inequality(LGI) and no-signaling-in-time(NSIT) conditions and compare the different effects between the Hamiltonian EP(HEP) and Liouvillian EP(LEP) on those violations. We consider an open system consisting of two coupled qubits and each qubit is contacted with a thermal bath at a different temperature. In the case of omitting quantum jumps, we find that the system exhibits a second-order HEP, which separates the parameter space into an overdamped regime and an underdamped regime. In this situation, the LGI and NSIT conditions can be violated in both regimes and not violated at the HEP. In the case of without omitting quantum jumps, we find that the system exhibits a third-order LEP, which also separates the parameter space into an overdamped regime and an underdamped regime. In this situation, the LGI can only be violated in the underdamped regime with large coupling strength between the qubits.Conversely, the NSIT conditions can be violated in both regimes, as well as at the LEP, except in the overdamped regime with small coupling strength between the qubits. Comparing the violations of the LGI and NSIT conditions with HEP and LEP, we find that the quantum jumps would reduce the generation of coherence, enhance the decoherence, and lead to narrower parameter regimes that the LGI and NSIT conditions can be violated. Furthermore, in both cases,the NSIT conditions can be violated in a wider parameter regime than the LGI.展开更多
Purpose–This paper investigates how high-speed rail(HSR)influences socioeconomic inequality by providing the first systematic bibliometric review of research trends,methodological approaches and thematic structures.I...Purpose–This paper investigates how high-speed rail(HSR)influences socioeconomic inequality by providing the first systematic bibliometric review of research trends,methodological approaches and thematic structures.It examines whether HSR fosters balanced regional development or reinforces spatial disparities.Design/methodology/approach–Using the Bibliometrix R package,237 records were retrieved from the Web of Science(1985–2024).Citation indicators,keyword co-occurrence and collaboration networks were combined with natural language processing(NLP)to classify studies by territorial scale,methodology,economic variables and inequality outcomes.Findings–The paper offers the first structured overview of how the literature conceptualizes the link between HSR and inequality.It highlights persistent gaps–scarcity of city-level analyses,limited socioeconomic indicators and reliance on Chinese case studies–providing a foundation for more comparative and interdisciplinary research.Originality/value–This paper contributes by offering a structured overview of how the literature has conceptualized and measured the relationship between HSR and inequality.By identifying persistent research gaps–such as the scarcity of city-level analyses,limited use of socioeconomic indicators,and overreliance on Chinese case studies–it provides a foundation for more comparative and interdisciplinary approaches.The study informs policymakers and researchers on how to design future infrastructure projects that balance efficiency with equity.展开更多
In this paper,we explicitly establish Poincaréinequality for 1≤p<∞ over simple geometric domains,such as segment,rectangle,triangle or tetrahedron.We obtain sharper bounds of the constant in Poincaré in...In this paper,we explicitly establish Poincaréinequality for 1≤p<∞ over simple geometric domains,such as segment,rectangle,triangle or tetrahedron.We obtain sharper bounds of the constant in Poincaré inequality and,in particular,the explicit relation between the constant and the geometric characters of the domain.展开更多
Background:Blindness and vision impairment(BVI)continue to pose significant global public health challenges,disproportionately impacting vulnerable populations and further widening socioeconomic disparities.This study...Background:Blindness and vision impairment(BVI)continue to pose significant global public health challenges,disproportionately impacting vulnerable populations and further widening socioeconomic disparities.This study conducts a comprehensive evaluation of the global burden of BVI and the socioeconomic inequalities in its distribution from 1990 to 2021,aiming to provide insights for targeted intervention strategies.Methods:Using data from Global Burden of Disease 2021,this study performed a multiscale analysis of BVI burden,examining patterns at the global,regional and national levels.We quantified the disease burden using disability-adjusted life years DALY and prevalence rates.Temporal trends were analyzed by calculating estimated annual percentage changes(EAPC).Stratified assessments were carried out by sex and age group across 21 regions and 204 countries.The study also included comparative analyses of six major eye conditions and evaluated their associations with socio-demographic index(SDI).Results:Globally,the age-standardized prevalence of BVI increased from 12,453.52 per million(95%UI:10,287.58-15,226.09)in 1990 to 15,784.33 per million(12,761.44-19,502.32)in 2021,with an EAPC of 1.09%(95%UI:0.97-1.20).During this period,global DALYs attributable to BVI increased by 37.7%.Disease trends exhibited significant divergence,with near vision loss showing the steepest increase(EAPC:1.47%),while the prevalence of glaucoma declined(EAPC:-0.73%).Geographic disparities were pronounced,with substantial improvements observed in Equatorial Guinea(EAPC:-1.75)and worsening burdens in Benin(+0.54).Disease distribution demonstrated strong regional clustering,with near vision loss being predominant in Sub-Saharan Africa(64.47%)and East Asia(50.97%),while cataract was the most common condition in Oceania(33.86%).Females consistently bore a higher burden,particularly in South Asia(646.3 vs 563.2 DALYs).Moreover,we identified a strong inverse correlation between SDI and BVI burden(Ρ=-0.772 for DALYs).Conclusions:This study highlights the severe global burden of BVI and the significant cross-country inequality,particularly in low-and middle-income countries.It emphasizes the urgent need for targeted interventions and the integration of eye care into universal health policies to promote global health equity in the post-pandemic era.展开更多
Environmental inequality is a prevalent issue in developing countries undergoing urban expansion.Urban expansion induces the formation and evolution of environmental inequality by creating environmental and structural...Environmental inequality is a prevalent issue in developing countries undergoing urban expansion.Urban expansion induces the formation and evolution of environmental inequality by creating environmental and structural conditions that lead to the spatial relocation of environmental hazards and the socio-spatial segregation of different groups in developing countries.This study investigated the spatial patterns and temporal trends of environmental inequality under urban expansion in Guangzhou,a megacity in China.It considered how environmental disparities and socio-demographic attributes interact in terms of industrial pollution exposure using additive semiparametric quantile regression,combined with spatial visualisation,on the basis of the economic and population census data from 1990 to 2020.This study revealed that urban expansion sparked the spatial displacement of environmental risks and the social-spatial differentiation,exposing the peripheral regions and disadvantaged groups to higher environmental risks.A reciprocal transformation occurred between central and peripheral regions,as well as a process of redistributing environmental risks across social space.In the context of urban expansion in developing countries,the causes of environmental inequality shifted from individual socio-economic differences to structural factors,such as industrial layout and social division of labour in cities,leading to the spatial displacement and concealment of environmental inequality.This study provides insights and guidance for policymakers to address the issue of environmental inequality in the context of urban expansion.展开更多
Economic inequality is a persistent global issue with profound implications for mental health,particularly among older adults.Previous studies have largely focused on objective economic well-being indicators such as i...Economic inequality is a persistent global issue with profound implications for mental health,particularly among older adults.Previous studies have largely focused on objective economic well-being indicators such as income,employment status,and poverty.While these factors are crucial,emerging evidence suggests that welfare benefits and subjective economic well-being components of what can be deemed augmented economic well-being,may play equally significant roles in shaping psychological health among aging populations.This research explores how disparities in these aspects contribute to psychological distress in older adults.We highlight the role of financial security,government assistance pro-grams,and personal economic satisfaction.We propose policy interventions to mitigate adverse effects and emphasize the need for a holistic approach to econo-mic well-being to improve mental health outcomes in older adults.This study reveals that subjective financial security and access to welfare benefits often surpass income as predictors of mental health.These insights underscore the importance of broadening economic frameworks in aging research and deve-loping integrated policies to enhance financial and psychological well-being.展开更多
Clustering a social network is a process of grouping social actors into clusters where intra-cluster similarities among actors are higher than inter-cluster similarities. Clustering approaches, i.e. , k-medoids or hie...Clustering a social network is a process of grouping social actors into clusters where intra-cluster similarities among actors are higher than inter-cluster similarities. Clustering approaches, i.e. , k-medoids or hierarchical, use the distance function to measure the dissimilarities among actors. These distance functions need to fulfill various properties, including the triangle inequality (TI). However, in some cases, the triangle inequality might be violated, impacting the quality of the resulting clusters. With experiments, this paper explains how TI violates while performing traditional clustering techniques: k-medoids, hierarchical, DENGRAPH, and spectral clustering on social networks and how the violation of TI affects the quality of the resulting clusters.展开更多
Using real fields instead of complex ones, it was recently claimed, that all fermions are made of pairs of coupled fields (strings) with an internal tension related to mutual attraction forces, related to Planck’s co...Using real fields instead of complex ones, it was recently claimed, that all fermions are made of pairs of coupled fields (strings) with an internal tension related to mutual attraction forces, related to Planck’s constant. Quantum mechanics is described with real fields and real operators. Schrodinger and Dirac equations then are solved. The solution to Dirac equation gives four, real, 2-vectors solutions ψ1=(U1D1)ψ2=(U2D2)ψ3=(U3D3)ψ4=(U4D4)where (ψ1,ψ4) are coupled via linear combinations to yield spin-up and spin-down fermions. Likewise, (ψ2,ψ3) are coupled via linear combinations to represent spin-up and spin-down anti-fermions. For an incoming entangled pair of fermions, the combined solution is Ψin=c1ψ1+c4ψ4where c1and c4are some hidden variables. By applying a magnetic field in +Z and +x the theoretical results of a triple Stern-Gerlach experiment are predicted correctly. Then, by repeating Bell’s and Mermin Gedanken experiment with three magnetic filters σθ, at three different inclination angles θ, the violation of Bell’s inequality is proven. It is shown that all fermions are in a mixed state of spins and the ratio between spin-up to spin-down depends on the hidden variables.展开更多
In this note,we prove a logarithmic Sobolev inequality which holds for compact submanifolds without a boundary in manifolds with asymptotically nonnegative sectional curvature.Like the Michale-Simon Sobolev inequality...In this note,we prove a logarithmic Sobolev inequality which holds for compact submanifolds without a boundary in manifolds with asymptotically nonnegative sectional curvature.Like the Michale-Simon Sobolev inequality,this inequality contains a term involving the mean curvature.展开更多
Poverty and income inequality are problems faced by many countries including China.Since the implementation of Targeted Poverty Alleviation(TPA),absolute poverty has been eradicated,meanwhile,Chinese rural residents&#...Poverty and income inequality are problems faced by many countries including China.Since the implementation of Targeted Poverty Alleviation(TPA),absolute poverty has been eradicated,meanwhile,Chinese rural residents' income and inequality have experienced unprecedented new dynamics,but still,very few studies have focused on them.Hence,we attempt to examine the new trends in Chinese farmers' income inequality and to understand its causes during this period.We observe that China's urban-rural income ratio has been shrinking and the urban-rural inequality has been decreasing from 2014 to 2021.The reduction in the Theil index indicates a decrease in the regional inequality of farmers' income as well,and the decline in inter-regional inequality among eight economic zones contributes about 80% to increased equality.These new trends are caused by the fact that,with the TPA,the incomes of rural residents especially that in destitute areas,grew faster than that of urban residents and farmers in prosperous areas.The higher share of non-agricultural industry and agricultural mechanization level have significant positive impact on regional equality of farmers' income,while urban-rural dual structure has significant negative inhibitory effects.The lowest farmers' income and the highest inequality in the Northwest,and the slowest growth in the Northeast deserve more attention in rural Revitalization.From these findings,we propose four policy implications that would be applied to improve Chinese farmers' income equality,govern relative poverty,and achieve common prosperity in the post-poverty era.展开更多
基金supported by the NSFC(12171378)supported by the Characteristic innovation projects of universities in Guangdong province(2023K-TSCX381)+3 种基金supported by the Young Top-Talent program of Chongqing(CQYC2021059145)the Major Special Project of NSFC(12141101)the Science and Technology Research Program of Chongqing Municipal Education Commission(KJZD-K202200509)the Natural Science Foundation Project of Chongqing(CSTB2024NSCQ-MSX0937).
文摘An upper estimate of the new curvature entropy is provided,via the integral inequality of a concave function.For two origin-symmetric convex bodies in R^(n),this bound is sharper than the log-Minkowski inequality of curvature entropy.As its application,a novel proof of the log-Minkowski inequality of curvature entropy in the plane is given.
文摘Energy poverty in developing countries is a critical issue characterized by the lack of access to modern energy services,such as electricity and clean cooking facilities,as marked in SDG 7.This study explores the correlations between energy poverty,energy intensity,resource abundance,and income inequality,as these factors have been theorized to play important roles in influencing energy poverty in developing countries.By observing that the dataset is heterogeneous across the countries and over the time frame,we use the Method of Moments Quantile Regression(MMQR)to analyze our developing countries’data from 2000 to 2019.Our findings indicate that energy intensity is a significant factor influencing energy poverty,suggesting that higher energy consumption relative to the sample countries can exacerbate this issue.Additionally,we observe that income inequality within the sample countries is a critical determinant of energy poverty levels,highlighting the dynamics between economic disparity and access to energy resources.Interestingly,our study reveals that resource abundance acts as a blessing rather than a curse in terms of energy poverty,implying that countries rich in natural resources may have better opportunities to combat energy deprivation.Finally,we emphasize the vital role of financial markets in addressing energy poverty on a global scale,suggesting that robust financial systems can facilitate investments and innovations aimed at improving energy access for vulnerable populations.The results from the robustness analysis support the empirical results obtained from the main estimation.The empirical findings of the present study advance important comprehensions for policymakers to adopt energy policies that address the complex challenges of energy poverty and promote inclusive energy access.
文摘In this paper,we construct a power type functional which is the approximation functional of the Singular Trudinger-Moser functional.Moreover,we obtain the concentration level of the functional and show it converges to the concentration level of singular Trudinger-Moser functional on the unit ball.
基金Supported by Scientific Research Fund of Hunan Provincial Education Departmen(t23A0361)。
文摘An evolution inequality of Sobolev type involving a nonlinear convolution term is considered.By using the nonlinear capacity method and the contradiction argument,the non-existence of the nontrivial local weak solution is proved.
基金Supported by NSFC(No.12171062)the Natural Science Foundation of Chongqing(No.CSTB2022NSCQ-JQX0004)+1 种基金the Chongqing Talent Support Program(No.cstc2024ycjh-bgzxm0121)Science and Technology Project of Chongqing Education Committee(No.KJZD-M202300503)。
文摘The purpose of this article is to introduce a new method with a self-adaptive stepsize for approximating a common solution of monotone inclusion problems and variational inequality problems in reflexive Banach spaces.The strong convergence result for our method is established under some standard assumptions without any requirement of the knowledge of the Lipschitz constant of the mapping.Several numerical experiments are provided to verify the advantages and efficiency of proposed algorithms.
基金Supported by Shandong Provincial Natural Science Foundation(ZR2024MA053).
文摘The purpose of this paper is to study some famous inequalities in Euclidean space.We are able to reveal an elegant relation between the famous Selberg inequality and Bessel inequality in Euclidean space.
基金supported by National Natural Science Foundation of China(Grant No.72104246).
文摘This study examines the impact of artificial intelligence(AI)on carbon inequality(CI)in 67 countries from 1995 to 2019.The results suggest that(i)AI significantly amplifies CI both between and within countries due to its energy requirements and uneven deployment;(ii)trade openness and global value chain(GVC)positioning mitigate AI’s effect on inter-country CI,while robust governance—marked by larger government size and institutional transparency—curtails intra-country disparities;(iii)specific thresholds(trade openness>4.74,GVC position>−1.07,government size>2.90,transparency>−0.22)shift the impact of AI from exacerbating to reducing CI.The adverse effects of AI can be reversed through enhanced trade,GVC integration,and strong governance.Key policy implications:Policymakers must prioritize exceeding these thresholds to leverage AI for sustainable and equitable outcomes.This requires(a)promoting trade liberalization to spread the benefits of AI globally,reducing inter-country CI;(b)strengthening GVC participation to offset the carbon-intensive use of AI;(c)building government capacity and transparency to ensure fair adoption of AI domestically;and(d)embedding these strategies in climate policies to align AI with the long-term goals of environmental justice and the SDGs,particularly climate action(SDG 13)and reducing inequalities(SDG 10).
基金National Natural Science Foundation of China,No.42101424,No.42001115。
文摘Since 2000,China's investment in Africa has grown rapidly,following a steady upward trajectory.However,this influx of Chinese capital has sparked both economic and political controversies.By integrating multi-source data—from micro-level individual projects to national statistics—this study examines the impact of Chinese investment on African economic development between 2000 and 2022.The results reveal a significant positive correlation between Chinese investment and economic growth across different scales,with investment-intensive regions achieving stronger economic outcomes.The DID analysis indicates that the Belt and Road Initiative has contributed positively to Africa's economic development.Both static and dynamic panel models confirm that Chinese investment significantly stimulates growth,exhibiting notable lag effects.Furthermore,β-convergence models demonstrate that Chinese investment fosters economic convergence among African countries.Regarding regional inequality,the findings suggest that Chinese investment helps to narrow disparities across Africa,promoting a more balanced economic landscape.Overall,this research underscores the constructive role of China's investment in fostering economic growth and reducing inequality within the African context.
文摘In this paper,we establish a stability estimate for the isoperimetric inequality of horospherically convex domains in hyperbolic plane.This estimate involves a relationship between the Hausdorff distance to a geodesic ball and the deficit in the isoperimetric inequality,where the coefficient of the deficit is a universal constant.
基金supported by the National Science Fund for Distinguished Young Scholars(42225107)the National Natural Science Foundation of China(42001326,42371414,42171409,and 42271419)+1 种基金the Natural Science Foundation of Guangdong Province of China(2022A1515012207)the Basic and Applied Basic Research Project of Guangzhou Science and Technology Planning(202201011539)。
文摘Three-dimensional(3D)urban structures play a critical role in informing climate mitigation strategies aimed at the built environment and facilitating sustainable urban development.Regrettably,there exists a significant gap in detailed and consistent data on 3D building space structures with global coverage due to the challenges inherent in the data collection and model calibration processes.In this study,we constructed a global urban structure(GUS-3D)dataset,including building volume,height,and footprint information,at a 500 m spatial resolution using extensive satellite observation products and numerous reference building samples.Our analysis indicated that the total volume of buildings worldwide in2015 exceeded 1×10^(12)m^(3).Over the 1985 to 2015 period,we observed a slight increase in the magnitude of 3D building volume growth(i.e.,it increased from 166.02 km3 during the 1985–2000 period to 175.08km3 during the 2000–2015 period),while the expansion magnitudes of the two-dimensional(2D)building footprint(22.51×10^(3) vs 13.29×10^(3)km^(2))and urban extent(157×10^(3) vs 133.8×10^(3)km^(2))notably decreased.This trend highlights the significant increase in intensive vertical utilization of urban land.Furthermore,we identified significant heterogeneity in building space provision and inequality across cities worldwide.This inequality is particularly pronounced in many populous Asian cities,which has been overlooked in previous studies on economic inequality.The GUS-3D dataset shows great potential to deepen our understanding of the urban environment and creates new horizons for numerous 3D urban studies.
基金financially supported by the National Natural Science Foundation of China (Grants Nos. 11775019 and 11875086)。
文摘In this paper, we investigate the effect of exceptional points(EPs) on the violation of Leggett–Garg inequality(LGI) and no-signaling-in-time(NSIT) conditions and compare the different effects between the Hamiltonian EP(HEP) and Liouvillian EP(LEP) on those violations. We consider an open system consisting of two coupled qubits and each qubit is contacted with a thermal bath at a different temperature. In the case of omitting quantum jumps, we find that the system exhibits a second-order HEP, which separates the parameter space into an overdamped regime and an underdamped regime. In this situation, the LGI and NSIT conditions can be violated in both regimes and not violated at the HEP. In the case of without omitting quantum jumps, we find that the system exhibits a third-order LEP, which also separates the parameter space into an overdamped regime and an underdamped regime. In this situation, the LGI can only be violated in the underdamped regime with large coupling strength between the qubits.Conversely, the NSIT conditions can be violated in both regimes, as well as at the LEP, except in the overdamped regime with small coupling strength between the qubits. Comparing the violations of the LGI and NSIT conditions with HEP and LEP, we find that the quantum jumps would reduce the generation of coherence, enhance the decoherence, and lead to narrower parameter regimes that the LGI and NSIT conditions can be violated. Furthermore, in both cases,the NSIT conditions can be violated in a wider parameter regime than the LGI.
文摘Purpose–This paper investigates how high-speed rail(HSR)influences socioeconomic inequality by providing the first systematic bibliometric review of research trends,methodological approaches and thematic structures.It examines whether HSR fosters balanced regional development or reinforces spatial disparities.Design/methodology/approach–Using the Bibliometrix R package,237 records were retrieved from the Web of Science(1985–2024).Citation indicators,keyword co-occurrence and collaboration networks were combined with natural language processing(NLP)to classify studies by territorial scale,methodology,economic variables and inequality outcomes.Findings–The paper offers the first structured overview of how the literature conceptualizes the link between HSR and inequality.It highlights persistent gaps–scarcity of city-level analyses,limited socioeconomic indicators and reliance on Chinese case studies–providing a foundation for more comparative and interdisciplinary research.Originality/value–This paper contributes by offering a structured overview of how the literature has conceptualized and measured the relationship between HSR and inequality.By identifying persistent research gaps–such as the scarcity of city-level analyses,limited use of socioeconomic indicators,and overreliance on Chinese case studies–it provides a foundation for more comparative and interdisciplinary approaches.The study informs policymakers and researchers on how to design future infrastructure projects that balance efficiency with equity.
基金Supported by National Natural Science Foundation of China(Grant Nos.12001170 and 11601124)Innovative Funds Plan of Henan University of Technology(Grant No.2021ZKCJ11).
文摘In this paper,we explicitly establish Poincaréinequality for 1≤p<∞ over simple geometric domains,such as segment,rectangle,triangle or tetrahedron.We obtain sharper bounds of the constant in Poincaré inequality and,in particular,the explicit relation between the constant and the geometric characters of the domain.
基金supported by grants from the National Natural Science Foundation of China(82000901,82171084).
文摘Background:Blindness and vision impairment(BVI)continue to pose significant global public health challenges,disproportionately impacting vulnerable populations and further widening socioeconomic disparities.This study conducts a comprehensive evaluation of the global burden of BVI and the socioeconomic inequalities in its distribution from 1990 to 2021,aiming to provide insights for targeted intervention strategies.Methods:Using data from Global Burden of Disease 2021,this study performed a multiscale analysis of BVI burden,examining patterns at the global,regional and national levels.We quantified the disease burden using disability-adjusted life years DALY and prevalence rates.Temporal trends were analyzed by calculating estimated annual percentage changes(EAPC).Stratified assessments were carried out by sex and age group across 21 regions and 204 countries.The study also included comparative analyses of six major eye conditions and evaluated their associations with socio-demographic index(SDI).Results:Globally,the age-standardized prevalence of BVI increased from 12,453.52 per million(95%UI:10,287.58-15,226.09)in 1990 to 15,784.33 per million(12,761.44-19,502.32)in 2021,with an EAPC of 1.09%(95%UI:0.97-1.20).During this period,global DALYs attributable to BVI increased by 37.7%.Disease trends exhibited significant divergence,with near vision loss showing the steepest increase(EAPC:1.47%),while the prevalence of glaucoma declined(EAPC:-0.73%).Geographic disparities were pronounced,with substantial improvements observed in Equatorial Guinea(EAPC:-1.75)and worsening burdens in Benin(+0.54).Disease distribution demonstrated strong regional clustering,with near vision loss being predominant in Sub-Saharan Africa(64.47%)and East Asia(50.97%),while cataract was the most common condition in Oceania(33.86%).Females consistently bore a higher burden,particularly in South Asia(646.3 vs 563.2 DALYs).Moreover,we identified a strong inverse correlation between SDI and BVI burden(Ρ=-0.772 for DALYs).Conclusions:This study highlights the severe global burden of BVI and the significant cross-country inequality,particularly in low-and middle-income countries.It emphasizes the urgent need for targeted interventions and the integration of eye care into universal health policies to promote global health equity in the post-pandemic era.
基金Under the auspices of the National Natural Science Foundation of China(No.42271181,41871111)。
文摘Environmental inequality is a prevalent issue in developing countries undergoing urban expansion.Urban expansion induces the formation and evolution of environmental inequality by creating environmental and structural conditions that lead to the spatial relocation of environmental hazards and the socio-spatial segregation of different groups in developing countries.This study investigated the spatial patterns and temporal trends of environmental inequality under urban expansion in Guangzhou,a megacity in China.It considered how environmental disparities and socio-demographic attributes interact in terms of industrial pollution exposure using additive semiparametric quantile regression,combined with spatial visualisation,on the basis of the economic and population census data from 1990 to 2020.This study revealed that urban expansion sparked the spatial displacement of environmental risks and the social-spatial differentiation,exposing the peripheral regions and disadvantaged groups to higher environmental risks.A reciprocal transformation occurred between central and peripheral regions,as well as a process of redistributing environmental risks across social space.In the context of urban expansion in developing countries,the causes of environmental inequality shifted from individual socio-economic differences to structural factors,such as industrial layout and social division of labour in cities,leading to the spatial displacement and concealment of environmental inequality.This study provides insights and guidance for policymakers to address the issue of environmental inequality in the context of urban expansion.
文摘Economic inequality is a persistent global issue with profound implications for mental health,particularly among older adults.Previous studies have largely focused on objective economic well-being indicators such as income,employment status,and poverty.While these factors are crucial,emerging evidence suggests that welfare benefits and subjective economic well-being components of what can be deemed augmented economic well-being,may play equally significant roles in shaping psychological health among aging populations.This research explores how disparities in these aspects contribute to psychological distress in older adults.We highlight the role of financial security,government assistance pro-grams,and personal economic satisfaction.We propose policy interventions to mitigate adverse effects and emphasize the need for a holistic approach to econo-mic well-being to improve mental health outcomes in older adults.This study reveals that subjective financial security and access to welfare benefits often surpass income as predictors of mental health.These insights underscore the importance of broadening economic frameworks in aging research and deve-loping integrated policies to enhance financial and psychological well-being.
文摘Clustering a social network is a process of grouping social actors into clusters where intra-cluster similarities among actors are higher than inter-cluster similarities. Clustering approaches, i.e. , k-medoids or hierarchical, use the distance function to measure the dissimilarities among actors. These distance functions need to fulfill various properties, including the triangle inequality (TI). However, in some cases, the triangle inequality might be violated, impacting the quality of the resulting clusters. With experiments, this paper explains how TI violates while performing traditional clustering techniques: k-medoids, hierarchical, DENGRAPH, and spectral clustering on social networks and how the violation of TI affects the quality of the resulting clusters.
文摘Using real fields instead of complex ones, it was recently claimed, that all fermions are made of pairs of coupled fields (strings) with an internal tension related to mutual attraction forces, related to Planck’s constant. Quantum mechanics is described with real fields and real operators. Schrodinger and Dirac equations then are solved. The solution to Dirac equation gives four, real, 2-vectors solutions ψ1=(U1D1)ψ2=(U2D2)ψ3=(U3D3)ψ4=(U4D4)where (ψ1,ψ4) are coupled via linear combinations to yield spin-up and spin-down fermions. Likewise, (ψ2,ψ3) are coupled via linear combinations to represent spin-up and spin-down anti-fermions. For an incoming entangled pair of fermions, the combined solution is Ψin=c1ψ1+c4ψ4where c1and c4are some hidden variables. By applying a magnetic field in +Z and +x the theoretical results of a triple Stern-Gerlach experiment are predicted correctly. Then, by repeating Bell’s and Mermin Gedanken experiment with three magnetic filters σθ, at three different inclination angles θ, the violation of Bell’s inequality is proven. It is shown that all fermions are in a mixed state of spins and the ratio between spin-up to spin-down depends on the hidden variables.
基金Supported by the NSFC(11771087,12171091 and 11831005)。
文摘In this note,we prove a logarithmic Sobolev inequality which holds for compact submanifolds without a boundary in manifolds with asymptotically nonnegative sectional curvature.Like the Michale-Simon Sobolev inequality,this inequality contains a term involving the mean curvature.
基金supported by the GanSu Provincial Science and Technology Program(No.22ZD6FA005)the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDA23060704).
文摘Poverty and income inequality are problems faced by many countries including China.Since the implementation of Targeted Poverty Alleviation(TPA),absolute poverty has been eradicated,meanwhile,Chinese rural residents' income and inequality have experienced unprecedented new dynamics,but still,very few studies have focused on them.Hence,we attempt to examine the new trends in Chinese farmers' income inequality and to understand its causes during this period.We observe that China's urban-rural income ratio has been shrinking and the urban-rural inequality has been decreasing from 2014 to 2021.The reduction in the Theil index indicates a decrease in the regional inequality of farmers' income as well,and the decline in inter-regional inequality among eight economic zones contributes about 80% to increased equality.These new trends are caused by the fact that,with the TPA,the incomes of rural residents especially that in destitute areas,grew faster than that of urban residents and farmers in prosperous areas.The higher share of non-agricultural industry and agricultural mechanization level have significant positive impact on regional equality of farmers' income,while urban-rural dual structure has significant negative inhibitory effects.The lowest farmers' income and the highest inequality in the Northwest,and the slowest growth in the Northeast deserve more attention in rural Revitalization.From these findings,we propose four policy implications that would be applied to improve Chinese farmers' income equality,govern relative poverty,and achieve common prosperity in the post-poverty era.
