The rise in online home delivery services(OHDS)has had a significant impact on how urban services are supplied and used in recent years.Studies on the spatial accessibility of OHDS are emerging,but few is known about ...The rise in online home delivery services(OHDS)has had a significant impact on how urban services are supplied and used in recent years.Studies on the spatial accessibility of OHDS are emerging,but few is known about the temporal dimension of OHDS accessibility as well as the geographic and socioeconomic differences in the spatiotemporal accessibility of OHDS.This study measures the spatiotemporal accessibility of four types of OHDS,namely leisure,fresh and convenient,medical,and catering services.The geographic and socioeconomic disparities in the spatiotemporal accessibility of these four types of OHDS are then identified using spatial statistical methods and the Kruskal-Wallis test(K-W test).The case study in Nanjing,China,suggests that:1)spatiotemporal accessibility better reflects the temporal variation of OHDS accessibility and avoids overestimation of OHDS accessibility when only considering its spatial dimension.2)The spatiotemporal accessibility of OHDS varies geographically and socioeconomically.Neighborhoods located in the main city or neighborhoods with higher housing prices,higher population density,and higher point of interest(POI)mix have better OHDS spatiotemporal accessibility.Our study contributes to the understanding of OHDS accessibility from a spatiotemporal perspective,and the empirical insights can assist policymakers in creating intervention plans that take into account variations in OHDS spatiotemporal accessibility.展开更多
Cities in deltas are vulnerable to climate change, especially their unembanked neighborhoods that are not protected by dikes. Rising sea levels and extreme water levels in the rivers can lead to the flooding of these ...Cities in deltas are vulnerable to climate change, especially their unembanked neighborhoods that are not protected by dikes. Rising sea levels and extreme water levels in the rivers can lead to the flooding of these urban areas. The Netherlands has a long history in water management. However, building dikes and the elevation of land are traditionally treated as rather stand-alone measures. Attention is rarely paid to the surrounding area, let alone to the complex context of cities and certainly not to disadvantaged neighborhoods. Yet, inner-city area redevelopment may provide opportunities to integrate flood management in these planning processes. In order to investigate the support of stakeholders for risk-reducing adaptive measures and more resilient measures, we did research in an unembanked inner-city area in the city of Rotterdam (The Netherlands), in which we conducted in-depth interviews with the central stakeholders. The main conclusion is that the most important barriers for integrating climate adaptation measures into that neighborhood are the fragmentation of water-safety policy (e.g. elevation of rebuilding locations) and the hierarchical governance arrangement in water management. This type of fragmentation led on its turn to fragmentation with other policy goals for the neighborhood. It also led to fragmentation between different areas in the same neighborhood that received political attention and those that are excluded from water-safety policy. This questions the approach in terms of social justice. An important side effect is that this governance arrangement also restricted innovation towards climate adaptation. Therefore, integrating water-safety policies in urban planning (in its capacity as a more integrative and comprehensive spatial approach) should be considered the best option to increase the adaptive capacity in delta cities. Not only can the negative effects in terms of policy fragmentation be dealt with effectively, but also spatial fragmentation can be tackled.展开更多
Cities' urban morphology is the result of historic, cultural, political and social processes. The historical cores in Mexican cities have high cultural diversity, which also intermingle pre-Hispanic cultures with col...Cities' urban morphology is the result of historic, cultural, political and social processes. The historical cores in Mexican cities have high cultural diversity, which also intermingle pre-Hispanic cultures with colonial forms, as well with modernity and post-modernity irruption. The case study is Santa Barbara's neighborhood in Toluca City, which was founded in 1524, and the case study was the first neighborhood in Toluca's historical core. At present time, this neighborhood is considered as one of the most dangerous places in the city's historical core, therefore, it has been abandoned. This paper will display the changes in urban morphology of the neighborhood through the years from 1877 to 2010. For site evaluation, the methodologies of Ashihara (1982) and Lynch's (1961) were used in order to analyze positive and negative spaces, as well as main street visual features, street and avenue directions, street circulation and street circulation path configuration. The results show that the focal nodes are a key factor for economic and social reactivation, with which, through urban activation of vacant lots and the traditional use of the streets as public space, is possible to generate centripetal development to restructure the neighborhood.展开更多
The percolation fields constructed around the elements of a cluster system in the phase spaces of properties are studied.It is shown that such neighborhoods significantly increase the number of structure parameters of...The percolation fields constructed around the elements of a cluster system in the phase spaces of properties are studied.It is shown that such neighborhoods significantly increase the number of structure parameters of the system under study,expanding the possibilities of analytical description.To study the structure and properties of such systems in the proposed model,a three-dimensional continuum percolation problem with interacting elements is solved.The dependences of the structure and properties of clusters on the parameters of the generation processes of the cluster system are studied,and analytical dependences are obtained.展开更多
The yield map is generated by fitting the yield surface shape of yield monitor data mainly using paraboloid cones on floating neighborhoods. Each yield map value is determined by the fit of such a cone on an elliptica...The yield map is generated by fitting the yield surface shape of yield monitor data mainly using paraboloid cones on floating neighborhoods. Each yield map value is determined by the fit of such a cone on an elliptical neighborhood that is wider across the harvest tracks than it is along them. The coefficients of regression for modeling the paraboloid cones and the scale parameter are estimated using robust weighted M-estimators where the weights decrease quadratically from 1 in the middle to zero at the border of the selected neighborhood. The robust way of estimating the model parameters supersedes a procedure for detecting outliers. For a given neighborhood shape, this yield mapping method is implemented by the Fortran program paraboloidmapping.exe, which can be downloaded from the web. The size of the selected neighborhood is considered appropriate if the variance of the yield map values equals the variance of the true yields, which is the difference between the variance of the raw yield data and the error variance of the yield monitor. It is estimated using a robust variogram on data that have not had the trend removed.展开更多
This study reflects on the impact that the neighborhoods’in-between spaces have on:spatial perception,social interaction,and security.These sites,characterized by their abandonment and deterioration,can also be seen ...This study reflects on the impact that the neighborhoods’in-between spaces have on:spatial perception,social interaction,and security.These sites,characterized by their abandonment and deterioration,can also be seen as crucial spaces of opportunity for cities,in the architectural,urban and landscape research.This paper aims to analyze the sociospatial relationships in the neighborhoods’in-between spaces and examine the impact of inbetween space configuration on urban habitability.The investigation draws on a survey of perception to residents about the requirements for a suitable social interaction in these spaces.This study was developed in a neighborhood in the city periphery,characterized by their social dynamics and location in a nature conservation area.The findings indicate that the appropriation process,activities,and collective practices are dependent on the spatial legibility,in this case when this increases,gives rise to improve the habitability and the rehabilitation of the in-between space.Furthermore,the lack of design on in-between spaces substantially affects the use of these spaces and the social interaction among residents.展开更多
With rapid urbanization,millions of rural villagers have become urban citizens in China.This paper estimates the effect of the in situ urbanization policy on an individual's health by employing the difference-in-d...With rapid urbanization,millions of rural villagers have become urban citizens in China.This paper estimates the effect of the in situ urbanization policy on an individual's health by employing the difference-in-differences framework and using panel survey data from the China Family Panel Studies.Our findings show that this program,unlike other kinds of urbanization,which have had negative impacts on mental health or made people smoke or drink more,increased people's self-reported health status significantly.Further mechanism analysis reveals that the in situ urbanization policy afected health by increasing people's confidence in the future,their satisfaction with their current lives,and their medical insurance enrollment.This study highlights the importance of"the city comes to villagers"urbanization in China,and it can play an essential role in advancing the urbanization rate and avoiding the negative impacts of urbanization on health.展开更多
A path-factor is a spanning subgraph F of G such that every component of F is a path with at least two vertices.Let k≥2 be an integer.A P_(≥k)-factor of G means a path factor in which each component is a path with a...A path-factor is a spanning subgraph F of G such that every component of F is a path with at least two vertices.Let k≥2 be an integer.A P_(≥k)-factor of G means a path factor in which each component is a path with at least k vertices.A graph G is a P_(≥k)-factor covered graph if for any e∈E(G),G has a P_(≥k)-factor including e.Letβbe a real number with 1/3≤β≤1 and k be a positive integer.We verify that(ⅰ)a k-connected graph G of order n with n≥5k+2 has a P_(≥3)-factor if|NG(I)|>β(n-3k-1)+k for every independent set I of G with|I|=「β(2k+1)」;(ⅱ)a(k+1)-connected graph G of order n with n≥5k+2 is a P_(≥3)-factor covered graph if|NG(I)|>β(n-3k-1)+k+1 for every independent set I of G with|I|=「β(2k+1)」.展开更多
With the advancement of the transformation,the contradiction between the residents’demand for a better living environment and the convenience of living in the settlements comes to the fore.Effective identification,or...With the advancement of the transformation,the contradiction between the residents’demand for a better living environment and the convenience of living in the settlements comes to the fore.Effective identification,organic integration,timely adoption,and correct decision-making for the transformation of old neighborhoods are pressing issues in the transformation of old neighborhoods.Therefore,this paper takes the green building evaluation standards of various countries as the research basis and support for the construction of the transformation strategy of old neighborhoods.Through the collection and comparative analysis of the indicators of green building evaluation standards,the index system of transformation is formed,and it also provides a certain foundation for the subsequent related research.展开更多
Water quality deterioration often occurs in secondary water supply systems(SWSSs), and increased heavy metal concentrations can be a serious problem. In this survey, twelve residential neighborhoods were selected to i...Water quality deterioration often occurs in secondary water supply systems(SWSSs), and increased heavy metal concentrations can be a serious problem. In this survey, twelve residential neighborhoods were selected to investigate the influence of SWSSs on the seasonal changes in heavy metal concentrations from input water to tank and tap water. The concentrations of nine evaluated heavy metals in all groups of water samples were found to be far below the specified standard levels in China. The concentrations of Fe, Mn, and Zn increased significantly from the input water samples to the tank and tap water samples in spring and summer( p < 0.05), especially for the water samples that had been stagnant for a long time. Negative correlations were found between most of the heavy metals and residual chlorine(Fe, Cu, Zn, and As, r =-0.186 to-0.519, p < 0.05). In particular, a high negative correlation was observed between Fe and residual chlorine( r =-0.489 to-0.519, p < 0.01) in spring and summer. Fe and Mn displayed positive correlations with turbidity( r = 0.672 and 0.328, respectively;p < 0.05). In addition, Cr and As were found to be positively associated with some nutrients(NO, TN, and SO;r = 0.420-0.786, p < 0.01). The material of the storage tanks had little influence on the difference in heavy metal concentrations. Overall, this survey illustrated that SWSSs may pose a chronic threat to water quality and could provide useful information for practitioners.展开更多
For decades,the immune system has been associated with host protection against infectious pathogens or tumors,while also contributing to autoimmunity.Notwithstanding,this paradigm is now changing,with recent studies h...For decades,the immune system has been associated with host protection against infectious pathogens or tumors,while also contributing to autoimmunity.Notwithstanding,this paradigm is now changing,with recent studies highlighting novel roles for immune mediators in the maintenance of steady-state tissue homeostasis.In this perspective,we review some of the latest findings featuring immune modulators of the nervous system pathophysiology,with a special focus on interleukin(IL)-17.展开更多
The structure of plant communities at local scales depends on both the spatial heterogeneity of abiotic environmental factors and the biotic interactions within the community.However,although environmental filtering d...The structure of plant communities at local scales depends on both the spatial heterogeneity of abiotic environmental factors and the biotic interactions within the community.However,although environmental filtering due to microtopographic heterogeneity and resource competition among plants caused by spatial variation in tree density and size are considered to be very important in explaining the mechanisms of community assembly,their effects on the processes of individual mortality and recruitment in natural forest regeneration,as well as their relative contributions,are still poorly understood.To address this,we established a 12-ha permanent plot in a subtropical evergreen broad-leaved forest area and measured microtopographic variables such as elevation,slope,aspect,and terrain position index(TPI)using a total station.We monitored the individual mortality and recruitment in forest natural regeneration through repeated surveys at 5-year intervals.We fitted spatial covariance models to jointly use multiple factors from three groups of variables(microtopographic effect,neighborhood density effects,neighborhood size effects)as explanatory variables to analyze their roles in driving the mortality and recruitment of all individual and 12 dominant species in forest natural regeneration at the neighborhood scale.Our results show that:(1)In the crucial early stages of secondary forest restoration,natural regeneration is influenced by a synergy of environmental filtering,due to microtopographic heterogeneity,and resource competition among plants.(2)For distinct species responses,evergreen dominant species'mortality is largely explained by neighborhood effects,while deciduous species are more affected by topographic factors.Furthermore,the adverse effects of larger conspecific trees on younger trees indicate a pattern of competitive pressure leading to mortality among regenerating trees,such pattern emphasis the influence of parent trees on natural regeneration.(3)As trees grow,their interaction with these stressors evolves,suggesting a shift in their resource acquisition strategies and response to neighborhood effects and environmental factors.Despite these changes,the relative importance of topographic factors in determining survival and recruitment success remains constant.This research highlights the importance of considering both environmental and neighborhood effects in forest management,particularly in early secondary forest restoration.展开更多
Geolocating social media users aims to discover the real geographical locations of users from their publicly available data,which can support online location-based applications such as disaster alerts and local conten...Geolocating social media users aims to discover the real geographical locations of users from their publicly available data,which can support online location-based applications such as disaster alerts and local content recommen-dations.Social relationship-based methods represent a classical approach for geolocating social media.However,geographically proximate relationships are sparse and challenging to discern within social networks,thereby affecting the accuracy of user geolocation.To address this challenge,we propose user geolocation methods that integrate neighborhood geographical distribution and social structure influence(NGSI)to improve geolocation accuracy.Firstly,we propose a method for evaluating the homophily of locations based on the k-order neighbor-hood geographic distribution(k-NGD)similarity among users.There are notable differences in the distribution of k-NGD similarity between location-proximate and non-location-proximate users.Exploiting this distinction,we filter out non-location-proximate social relationships to enhance location homophily in the social network.To better utilize the location-proximate relationships in social networks,we propose a graph neural network algorithm based on the social structure influence.The algorithm enables us to perform a weighted aggregation of the information of users’multi-hop neighborhood,thereby mitigating the over-smoothing problem of user features and improving user geolocation performance.Experimental results on real social media dataset demonstrate that the neighborhood geographical distribution similarity metric can effectively filter out non-location-proximate social relationships.Moreover,compared with 7 existing social relationship-based user positioning methods,our proposed method can achieve multi-granularity user geolocation and improve the accuracy by 4.84%to 13.28%.展开更多
A spectral analysis of the vertical positions and velocities of 374 open star clusters(OSCs)was carried out.We took these OSCs from the Hunt and Reffert catalog;they have an average age of about 10 million years,and a...A spectral analysis of the vertical positions and velocities of 374 open star clusters(OSCs)was carried out.We took these OSCs from the Hunt and Reffert catalog;they have an average age of about 10 million years,and are located on the galactic plane XY in a narrow zone inclined by 25°to the galactic axis Y.The following estimates of the parameters of the Radcliffe wave were obtained:(a)the maximum value in periodic perturbations of vertical coordinates Z_(max)=92±10pc with the wavelength of these perturbations λ_(z)=4.82±0.09 kpc;(b)the maximum value of the velocity of vertical disturbances Wmax=4.36±0.12km s^(-1) with disturbance wavelengthλ_(W)=1.78±0.02 kpc.Note that the results of the vertical velocity analysis are first-class in accuracy and completely new.展开更多
Technological advancements in unmanned aerial vehicles(UAVs)have revolutionized various industries,enabling the widespread adoption of UAV-based solutions.In engineering management,UAV-based inspection has emerged as ...Technological advancements in unmanned aerial vehicles(UAVs)have revolutionized various industries,enabling the widespread adoption of UAV-based solutions.In engineering management,UAV-based inspection has emerged as a highly efficient method for identifying hidden risks in high-risk construction environments,surpassing traditional inspection techniques.Building on this foundation,this paper delves into the optimization of UAV inspection routing and scheduling,addressing the complexity introduced by factors such as no-fly zones,monitoring-interval time windows,and multiple monitoring rounds.To tackle this challenging problem,we propose a mixed-integer linear programming(MILP)model that optimizes inspection task assignments,monitoring sequence schedules,and charging decisions.The comprehensive consideration of these factors differentiates our problem from conventional vehicle routing problem(VRP),leading to a mathematically intractable model for commercial solvers in the case of large-scale instances.To overcome this limitation,we design a tailored variable neighborhood search(VNS)metaheuristic,customizing the algorithm to efficiently solve our model.Extensive numerical experiments are conducted to validate the efficacy of our proposed algorithm,demonstrating its scalability for both large-scale and real-scale instances.Sensitivity experiments and a case study based on an actual engineering project are also conducted,providing valuable insights for engineering managers to enhance inspection work efficiency.展开更多
To provide the supplier with the minimizum vehicle travel distance in the distribution process of goods in three situations of new customer demand,customer cancellation service,and change of customer delivery address,...To provide the supplier with the minimizum vehicle travel distance in the distribution process of goods in three situations of new customer demand,customer cancellation service,and change of customer delivery address,based on the ideas of pre-optimization and real-time optimization,a two-stage planning model of dynamic demand based vehicle routing problem with time windows was established.At the pre-optimization stage,an improved genetic algorithm was used to obtain the pre-optimized distribution route,a large-scale neighborhood search method was integrated into the mutation operation to improve the local optimization performance of the genetic algorithm,and a variety of operators were introduced to expand the search space of neighborhood solutions;At the real-time optimization stage,a periodic optimization strategy was adopted to transform a complex dynamic problem into several static problems,and four neighborhood search operators were used to quickly adjust the route.Two different scale examples were designed for experiments.It is proved that the algorithm can plan the better route,and adjust the distribution route in time under the real-time constraints.Therefore,the proposed algorithm can provide theoretical guidance for suppliers to solve the dynamic demand based vehicle routing problem.展开更多
https://www.sciencedirect.com/journal/energy-and-buildings/vol/308/suppl/C.Volume 308,1.April 2024.[OA](1)Equity-oriented power sharing and demand response for enhancing green energy access in mixed communities.by Pet...https://www.sciencedirect.com/journal/energy-and-buildings/vol/308/suppl/C.Volume 308,1.April 2024.[OA](1)Equity-oriented power sharing and demand response for enhancing green energy access in mixed communities.by Petr Musilek、Akhtar Hussain,Article 114029.Abstract:The distribution of renewable energy resources(RERs)is currently uneven and is largely influenced by their affordability across various communities.This has led to disparities in access to green energy for different community members.To address these inequalities,this study proposes an equity-oriented powersharing mechanism that incorporates demand response(DR).The implementation ofthis approach will increase the availability of green energy for all members of the community in mixed neighborhoods.First,a DR program is introduced for conventional homes(i.e.,homes without RERs)to maximize the consumption of RERs by shifting their load to RER excess intervals.Then,a proportionally fair mechanism is introduced to distribute the available resources among community members during times of high excess.The objective is to minimize the grid dependence of community members by reducing their reliance on purchasing power from the grid.To ensure renewable energy homes(i.e.,homes with installed RERs)maintain their green energy access,additional constraints are put in place to prioritize their energy needs when compared to the non-sharing case.Three indices(green energy access,grid dependence,and cost reduction)are introduced to evaluate the performance of the proposed method in different cases:the base case,the powersharing-only case,and the case of power-sharing with the DR.Finally,the impact of different seasons,day types,and userdefined parameters is analyzed.Simulations have shown that the proposed method can significantly increase the green energy access of conventional homes without affecting the access to green energy of renewable energy homes.It also decreases the grid dependence and the electricity cost of the entire community.展开更多
This study used the China Meteorological Administration(CMA)three-source fusion gridded precipitation analysis data as a reference to evaluate the precipitation forecast performance of the European Centre for Medium-R...This study used the China Meteorological Administration(CMA)three-source fusion gridded precipitation analysis data as a reference to evaluate the precipitation forecast performance of the European Centre for Medium-Range Weather Forecasts(ECMWF)model for China from 2017 to 2022.The main conclusions are as follows.The precipitation forecast capability of the ECMWF model for China has gradually improved from 2017 to 2022.Various scores such as bias,equitable threat score(ETS),and Fractions Skill Score(FSS)showed improvements for different categories of precipitation.The bias of light rain forecasts overall adjusted towards smaller values,and the increase in forecast scores was greater in the warm season than in the cold season.The ETS for torrential rain more intense categories significantly increased,although there were large fluctuations in bias across different months.The model exhibited higher precipitation bias in most areas of North China,indicating overprediction,while it showed lower bias in South China,indicating underprediction.The ETSs indicate that the model performed better in forecasting precipitation in the northeastern part of China without the influence of climatic background conditions.Comparison of the differences between the first period and the second period of the forecast shows that the precipitation amplitude in the ECMWF forecast shifted from slight underestimation to overestimation compared to that of CMPAS05,reducing the likelihood of missing extreme precipitation events.The improvement in ETS is mainly due to the reduction in bias and false alarm rates and,more importantly,an increase in the hit rate.From 2017 to 2022,the area coverage error of model precipitation forecast relative to observations showed a decreasing trend at different scales,while the FSS showed an increasing trend,with the highest FSS observed in 2021.The ETS followed a parabolic trend with increasing neighborhood radius,with the better ETS neighborhood radius generally being larger for moderate rain and heavy rain compared with light rain and torrential rain events.展开更多
With the increasing demand for electrical services,wind farm layout optimization has been one of the biggest challenges that we have to deal with.Despite the promising performance of the heuristic algorithm on the rou...With the increasing demand for electrical services,wind farm layout optimization has been one of the biggest challenges that we have to deal with.Despite the promising performance of the heuristic algorithm on the route network design problem,the expressive capability and search performance of the algorithm on multi-objective problems remain unexplored.In this paper,the wind farm layout optimization problem is defined.Then,a multi-objective algorithm based on Graph Neural Network(GNN)and Variable Neighborhood Search(VNS)algorithm is proposed.GNN provides the basis representations for the following search algorithm so that the expressiveness and search accuracy of the algorithm can be improved.The multi-objective VNS algorithm is put forward by combining it with the multi-objective optimization algorithm to solve the problem with multiple objectives.The proposed algorithm is applied to the 18-node simulation example to evaluate the feasibility and practicality of the developed optimization strategy.The experiment on the simulation example shows that the proposed algorithm yields a reduction of 6.1% in Point of Common Coupling(PCC)over the current state-of-the-art algorithm,which means that the proposed algorithm designs a layout that improves the quality of the power supply by 6.1%at the same cost.The ablation experiments show that the proposed algorithm improves the power quality by more than 8.6% and 7.8% compared to both the original VNS algorithm and the multi-objective VNS algorithm.展开更多
Against the backdrop of the international political and economic configuration featuring that“the East is rising and the West is declining”,relations between China and its neighboring countries enjoy steady developm...Against the backdrop of the international political and economic configuration featuring that“the East is rising and the West is declining”,relations between China and its neighboring countries enjoy steady development in general.However,the return of the Cold War mentality,rampant protectionism and prominent security governance issues have seriously threatened peace and stability in China’s neighboring region.展开更多
基金Under the auspices of National Natural Science Foundation of China (No.42330510)。
文摘The rise in online home delivery services(OHDS)has had a significant impact on how urban services are supplied and used in recent years.Studies on the spatial accessibility of OHDS are emerging,but few is known about the temporal dimension of OHDS accessibility as well as the geographic and socioeconomic differences in the spatiotemporal accessibility of OHDS.This study measures the spatiotemporal accessibility of four types of OHDS,namely leisure,fresh and convenient,medical,and catering services.The geographic and socioeconomic disparities in the spatiotemporal accessibility of these four types of OHDS are then identified using spatial statistical methods and the Kruskal-Wallis test(K-W test).The case study in Nanjing,China,suggests that:1)spatiotemporal accessibility better reflects the temporal variation of OHDS accessibility and avoids overestimation of OHDS accessibility when only considering its spatial dimension.2)The spatiotemporal accessibility of OHDS varies geographically and socioeconomically.Neighborhoods located in the main city or neighborhoods with higher housing prices,higher population density,and higher point of interest(POI)mix have better OHDS spatiotemporal accessibility.Our study contributes to the understanding of OHDS accessibility from a spatiotemporal perspective,and the empirical insights can assist policymakers in creating intervention plans that take into account variations in OHDS spatiotemporal accessibility.
文摘Cities in deltas are vulnerable to climate change, especially their unembanked neighborhoods that are not protected by dikes. Rising sea levels and extreme water levels in the rivers can lead to the flooding of these urban areas. The Netherlands has a long history in water management. However, building dikes and the elevation of land are traditionally treated as rather stand-alone measures. Attention is rarely paid to the surrounding area, let alone to the complex context of cities and certainly not to disadvantaged neighborhoods. Yet, inner-city area redevelopment may provide opportunities to integrate flood management in these planning processes. In order to investigate the support of stakeholders for risk-reducing adaptive measures and more resilient measures, we did research in an unembanked inner-city area in the city of Rotterdam (The Netherlands), in which we conducted in-depth interviews with the central stakeholders. The main conclusion is that the most important barriers for integrating climate adaptation measures into that neighborhood are the fragmentation of water-safety policy (e.g. elevation of rebuilding locations) and the hierarchical governance arrangement in water management. This type of fragmentation led on its turn to fragmentation with other policy goals for the neighborhood. It also led to fragmentation between different areas in the same neighborhood that received political attention and those that are excluded from water-safety policy. This questions the approach in terms of social justice. An important side effect is that this governance arrangement also restricted innovation towards climate adaptation. Therefore, integrating water-safety policies in urban planning (in its capacity as a more integrative and comprehensive spatial approach) should be considered the best option to increase the adaptive capacity in delta cities. Not only can the negative effects in terms of policy fragmentation be dealt with effectively, but also spatial fragmentation can be tackled.
文摘Cities' urban morphology is the result of historic, cultural, political and social processes. The historical cores in Mexican cities have high cultural diversity, which also intermingle pre-Hispanic cultures with colonial forms, as well with modernity and post-modernity irruption. The case study is Santa Barbara's neighborhood in Toluca City, which was founded in 1524, and the case study was the first neighborhood in Toluca's historical core. At present time, this neighborhood is considered as one of the most dangerous places in the city's historical core, therefore, it has been abandoned. This paper will display the changes in urban morphology of the neighborhood through the years from 1877 to 2010. For site evaluation, the methodologies of Ashihara (1982) and Lynch's (1961) were used in order to analyze positive and negative spaces, as well as main street visual features, street and avenue directions, street circulation and street circulation path configuration. The results show that the focal nodes are a key factor for economic and social reactivation, with which, through urban activation of vacant lots and the traditional use of the streets as public space, is possible to generate centripetal development to restructure the neighborhood.
文摘The percolation fields constructed around the elements of a cluster system in the phase spaces of properties are studied.It is shown that such neighborhoods significantly increase the number of structure parameters of the system under study,expanding the possibilities of analytical description.To study the structure and properties of such systems in the proposed model,a three-dimensional continuum percolation problem with interacting elements is solved.The dependences of the structure and properties of clusters on the parameters of the generation processes of the cluster system are studied,and analytical dependences are obtained.
文摘The yield map is generated by fitting the yield surface shape of yield monitor data mainly using paraboloid cones on floating neighborhoods. Each yield map value is determined by the fit of such a cone on an elliptical neighborhood that is wider across the harvest tracks than it is along them. The coefficients of regression for modeling the paraboloid cones and the scale parameter are estimated using robust weighted M-estimators where the weights decrease quadratically from 1 in the middle to zero at the border of the selected neighborhood. The robust way of estimating the model parameters supersedes a procedure for detecting outliers. For a given neighborhood shape, this yield mapping method is implemented by the Fortran program paraboloidmapping.exe, which can be downloaded from the web. The size of the selected neighborhood is considered appropriate if the variance of the yield map values equals the variance of the true yields, which is the difference between the variance of the raw yield data and the error variance of the yield monitor. It is estimated using a robust variogram on data that have not had the trend removed.
基金We would like to express our gratitude to the Autonomous University of Baja California(UABC),the Master's and Doctoral Program in Architecture,Urbanism and Design(MyDAUD),as well as the National Council of Science and Technology(Conacyt).The project is linked to the paper:Habitability and post-covid.A study of urban connectivity in public,which has as code:402/3412.This project is internal to the university and it does not have funds.
文摘This study reflects on the impact that the neighborhoods’in-between spaces have on:spatial perception,social interaction,and security.These sites,characterized by their abandonment and deterioration,can also be seen as crucial spaces of opportunity for cities,in the architectural,urban and landscape research.This paper aims to analyze the sociospatial relationships in the neighborhoods’in-between spaces and examine the impact of inbetween space configuration on urban habitability.The investigation draws on a survey of perception to residents about the requirements for a suitable social interaction in these spaces.This study was developed in a neighborhood in the city periphery,characterized by their social dynamics and location in a nature conservation area.The findings indicate that the appropriation process,activities,and collective practices are dependent on the spatial legibility,in this case when this increases,gives rise to improve the habitability and the rehabilitation of the in-between space.Furthermore,the lack of design on in-between spaces substantially affects the use of these spaces and the social interaction among residents.
基金supported financially by the National Natural Science Foundation of China(Nos.71673282,72073059)the National Social Science Foundation of China(No.19ZDA116).
文摘With rapid urbanization,millions of rural villagers have become urban citizens in China.This paper estimates the effect of the in situ urbanization policy on an individual's health by employing the difference-in-differences framework and using panel survey data from the China Family Panel Studies.Our findings show that this program,unlike other kinds of urbanization,which have had negative impacts on mental health or made people smoke or drink more,increased people's self-reported health status significantly.Further mechanism analysis reveals that the in situ urbanization policy afected health by increasing people's confidence in the future,their satisfaction with their current lives,and their medical insurance enrollment.This study highlights the importance of"the city comes to villagers"urbanization in China,and it can play an essential role in advancing the urbanization rate and avoiding the negative impacts of urbanization on health.
文摘A path-factor is a spanning subgraph F of G such that every component of F is a path with at least two vertices.Let k≥2 be an integer.A P_(≥k)-factor of G means a path factor in which each component is a path with at least k vertices.A graph G is a P_(≥k)-factor covered graph if for any e∈E(G),G has a P_(≥k)-factor including e.Letβbe a real number with 1/3≤β≤1 and k be a positive integer.We verify that(ⅰ)a k-connected graph G of order n with n≥5k+2 has a P_(≥3)-factor if|NG(I)|>β(n-3k-1)+k for every independent set I of G with|I|=「β(2k+1)」;(ⅱ)a(k+1)-connected graph G of order n with n≥5k+2 is a P_(≥3)-factor covered graph if|NG(I)|>β(n-3k-1)+k+1 for every independent set I of G with|I|=「β(2k+1)」.
文摘With the advancement of the transformation,the contradiction between the residents’demand for a better living environment and the convenience of living in the settlements comes to the fore.Effective identification,organic integration,timely adoption,and correct decision-making for the transformation of old neighborhoods are pressing issues in the transformation of old neighborhoods.Therefore,this paper takes the green building evaluation standards of various countries as the research basis and support for the construction of the transformation strategy of old neighborhoods.Through the collection and comparative analysis of the indicators of green building evaluation standards,the index system of transformation is formed,and it also provides a certain foundation for the subsequent related research.
基金supported by the National Natural Science Foundation of China (Nos. 41861144023, U2005206)Xiamen Municipal Bureau of Science and Technology (No. YDZX20203502000003)。
文摘Water quality deterioration often occurs in secondary water supply systems(SWSSs), and increased heavy metal concentrations can be a serious problem. In this survey, twelve residential neighborhoods were selected to investigate the influence of SWSSs on the seasonal changes in heavy metal concentrations from input water to tank and tap water. The concentrations of nine evaluated heavy metals in all groups of water samples were found to be far below the specified standard levels in China. The concentrations of Fe, Mn, and Zn increased significantly from the input water samples to the tank and tap water samples in spring and summer( p < 0.05), especially for the water samples that had been stagnant for a long time. Negative correlations were found between most of the heavy metals and residual chlorine(Fe, Cu, Zn, and As, r =-0.186 to-0.519, p < 0.05). In particular, a high negative correlation was observed between Fe and residual chlorine( r =-0.489 to-0.519, p < 0.01) in spring and summer. Fe and Mn displayed positive correlations with turbidity( r = 0.672 and 0.328, respectively;p < 0.05). In addition, Cr and As were found to be positively associated with some nutrients(NO, TN, and SO;r = 0.420-0.786, p < 0.01). The material of the storage tanks had little influence on the difference in heavy metal concentrations. Overall, this survey illustrated that SWSSs may pose a chronic threat to water quality and could provide useful information for practitioners.
基金funded by the Fundacao para a Ciencia e Tecnologia(2020.00413.CEECIND and 2022.01244.PTDC,to JCR).
文摘For decades,the immune system has been associated with host protection against infectious pathogens or tumors,while also contributing to autoimmunity.Notwithstanding,this paradigm is now changing,with recent studies highlighting novel roles for immune mediators in the maintenance of steady-state tissue homeostasis.In this perspective,we review some of the latest findings featuring immune modulators of the nervous system pathophysiology,with a special focus on interleukin(IL)-17.
基金the Innovative Team Project of Nanjing Institute of Environmental Sciences MEE(ZX2023QT022)Sino-German Environmental Partnership PhaseⅢ:Strengthening Chinese environmental and nature conservation policy through dialogue+2 种基金The Central Public Welfare Scientific Institution Basal Research Fund,MEE(GYZX210302)Biodiversity Survey,Observation and Assessment Program of Ministry of Ecology and Environment of ChinaThe National Environmental Protection Public Welfare Industry Targeted Research Fund:Research and demonstration of key technologies for dynamic supervision of nature reserves(201509042)。
文摘The structure of plant communities at local scales depends on both the spatial heterogeneity of abiotic environmental factors and the biotic interactions within the community.However,although environmental filtering due to microtopographic heterogeneity and resource competition among plants caused by spatial variation in tree density and size are considered to be very important in explaining the mechanisms of community assembly,their effects on the processes of individual mortality and recruitment in natural forest regeneration,as well as their relative contributions,are still poorly understood.To address this,we established a 12-ha permanent plot in a subtropical evergreen broad-leaved forest area and measured microtopographic variables such as elevation,slope,aspect,and terrain position index(TPI)using a total station.We monitored the individual mortality and recruitment in forest natural regeneration through repeated surveys at 5-year intervals.We fitted spatial covariance models to jointly use multiple factors from three groups of variables(microtopographic effect,neighborhood density effects,neighborhood size effects)as explanatory variables to analyze their roles in driving the mortality and recruitment of all individual and 12 dominant species in forest natural regeneration at the neighborhood scale.Our results show that:(1)In the crucial early stages of secondary forest restoration,natural regeneration is influenced by a synergy of environmental filtering,due to microtopographic heterogeneity,and resource competition among plants.(2)For distinct species responses,evergreen dominant species'mortality is largely explained by neighborhood effects,while deciduous species are more affected by topographic factors.Furthermore,the adverse effects of larger conspecific trees on younger trees indicate a pattern of competitive pressure leading to mortality among regenerating trees,such pattern emphasis the influence of parent trees on natural regeneration.(3)As trees grow,their interaction with these stressors evolves,suggesting a shift in their resource acquisition strategies and response to neighborhood effects and environmental factors.Despite these changes,the relative importance of topographic factors in determining survival and recruitment success remains constant.This research highlights the importance of considering both environmental and neighborhood effects in forest management,particularly in early secondary forest restoration.
基金This work was supported by the National Key R&D Program of China(No.2022YFB3102904)the National Natural Science Foundation of China(No.62172435,U23A20305)Key Research and Development Project of Henan Province(No.221111321200).
文摘Geolocating social media users aims to discover the real geographical locations of users from their publicly available data,which can support online location-based applications such as disaster alerts and local content recommen-dations.Social relationship-based methods represent a classical approach for geolocating social media.However,geographically proximate relationships are sparse and challenging to discern within social networks,thereby affecting the accuracy of user geolocation.To address this challenge,we propose user geolocation methods that integrate neighborhood geographical distribution and social structure influence(NGSI)to improve geolocation accuracy.Firstly,we propose a method for evaluating the homophily of locations based on the k-order neighbor-hood geographic distribution(k-NGD)similarity among users.There are notable differences in the distribution of k-NGD similarity between location-proximate and non-location-proximate users.Exploiting this distinction,we filter out non-location-proximate social relationships to enhance location homophily in the social network.To better utilize the location-proximate relationships in social networks,we propose a graph neural network algorithm based on the social structure influence.The algorithm enables us to perform a weighted aggregation of the information of users’multi-hop neighborhood,thereby mitigating the over-smoothing problem of user features and improving user geolocation performance.Experimental results on real social media dataset demonstrate that the neighborhood geographical distribution similarity metric can effectively filter out non-location-proximate social relationships.Moreover,compared with 7 existing social relationship-based user positioning methods,our proposed method can achieve multi-granularity user geolocation and improve the accuracy by 4.84%to 13.28%.
文摘A spectral analysis of the vertical positions and velocities of 374 open star clusters(OSCs)was carried out.We took these OSCs from the Hunt and Reffert catalog;they have an average age of about 10 million years,and are located on the galactic plane XY in a narrow zone inclined by 25°to the galactic axis Y.The following estimates of the parameters of the Radcliffe wave were obtained:(a)the maximum value in periodic perturbations of vertical coordinates Z_(max)=92±10pc with the wavelength of these perturbations λ_(z)=4.82±0.09 kpc;(b)the maximum value of the velocity of vertical disturbances Wmax=4.36±0.12km s^(-1) with disturbance wavelengthλ_(W)=1.78±0.02 kpc.Note that the results of the vertical velocity analysis are first-class in accuracy and completely new.
基金supported by the National Natural Science Foundation of China(72201229,72025103,72394360,72394362,72361137001,72071173,and 71831008).
文摘Technological advancements in unmanned aerial vehicles(UAVs)have revolutionized various industries,enabling the widespread adoption of UAV-based solutions.In engineering management,UAV-based inspection has emerged as a highly efficient method for identifying hidden risks in high-risk construction environments,surpassing traditional inspection techniques.Building on this foundation,this paper delves into the optimization of UAV inspection routing and scheduling,addressing the complexity introduced by factors such as no-fly zones,monitoring-interval time windows,and multiple monitoring rounds.To tackle this challenging problem,we propose a mixed-integer linear programming(MILP)model that optimizes inspection task assignments,monitoring sequence schedules,and charging decisions.The comprehensive consideration of these factors differentiates our problem from conventional vehicle routing problem(VRP),leading to a mathematically intractable model for commercial solvers in the case of large-scale instances.To overcome this limitation,we design a tailored variable neighborhood search(VNS)metaheuristic,customizing the algorithm to efficiently solve our model.Extensive numerical experiments are conducted to validate the efficacy of our proposed algorithm,demonstrating its scalability for both large-scale and real-scale instances.Sensitivity experiments and a case study based on an actual engineering project are also conducted,providing valuable insights for engineering managers to enhance inspection work efficiency.
基金supported by Natural Science Foundation Project of Gansu Provincial Science and Technology Department(No.1506RJZA084)Gansu Provincial Education Department Scientific Research Fund Grant Project(No.1204-13).
文摘To provide the supplier with the minimizum vehicle travel distance in the distribution process of goods in three situations of new customer demand,customer cancellation service,and change of customer delivery address,based on the ideas of pre-optimization and real-time optimization,a two-stage planning model of dynamic demand based vehicle routing problem with time windows was established.At the pre-optimization stage,an improved genetic algorithm was used to obtain the pre-optimized distribution route,a large-scale neighborhood search method was integrated into the mutation operation to improve the local optimization performance of the genetic algorithm,and a variety of operators were introduced to expand the search space of neighborhood solutions;At the real-time optimization stage,a periodic optimization strategy was adopted to transform a complex dynamic problem into several static problems,and four neighborhood search operators were used to quickly adjust the route.Two different scale examples were designed for experiments.It is proved that the algorithm can plan the better route,and adjust the distribution route in time under the real-time constraints.Therefore,the proposed algorithm can provide theoretical guidance for suppliers to solve the dynamic demand based vehicle routing problem.
文摘https://www.sciencedirect.com/journal/energy-and-buildings/vol/308/suppl/C.Volume 308,1.April 2024.[OA](1)Equity-oriented power sharing and demand response for enhancing green energy access in mixed communities.by Petr Musilek、Akhtar Hussain,Article 114029.Abstract:The distribution of renewable energy resources(RERs)is currently uneven and is largely influenced by their affordability across various communities.This has led to disparities in access to green energy for different community members.To address these inequalities,this study proposes an equity-oriented powersharing mechanism that incorporates demand response(DR).The implementation ofthis approach will increase the availability of green energy for all members of the community in mixed neighborhoods.First,a DR program is introduced for conventional homes(i.e.,homes without RERs)to maximize the consumption of RERs by shifting their load to RER excess intervals.Then,a proportionally fair mechanism is introduced to distribute the available resources among community members during times of high excess.The objective is to minimize the grid dependence of community members by reducing their reliance on purchasing power from the grid.To ensure renewable energy homes(i.e.,homes with installed RERs)maintain their green energy access,additional constraints are put in place to prioritize their energy needs when compared to the non-sharing case.Three indices(green energy access,grid dependence,and cost reduction)are introduced to evaluate the performance of the proposed method in different cases:the base case,the powersharing-only case,and the case of power-sharing with the DR.Finally,the impact of different seasons,day types,and userdefined parameters is analyzed.Simulations have shown that the proposed method can significantly increase the green energy access of conventional homes without affecting the access to green energy of renewable energy homes.It also decreases the grid dependence and the electricity cost of the entire community.
基金Special Innovation and Development Program of China Meteorological Administration(CXFZ2022J023)Projects in Key Areas of Social Development in Shaanxi Province(2024SF-YBXM-556)Shaanxi Province Basic Research Pro-gram of Natural Science(2023-JC-QN-0285)。
文摘This study used the China Meteorological Administration(CMA)three-source fusion gridded precipitation analysis data as a reference to evaluate the precipitation forecast performance of the European Centre for Medium-Range Weather Forecasts(ECMWF)model for China from 2017 to 2022.The main conclusions are as follows.The precipitation forecast capability of the ECMWF model for China has gradually improved from 2017 to 2022.Various scores such as bias,equitable threat score(ETS),and Fractions Skill Score(FSS)showed improvements for different categories of precipitation.The bias of light rain forecasts overall adjusted towards smaller values,and the increase in forecast scores was greater in the warm season than in the cold season.The ETS for torrential rain more intense categories significantly increased,although there were large fluctuations in bias across different months.The model exhibited higher precipitation bias in most areas of North China,indicating overprediction,while it showed lower bias in South China,indicating underprediction.The ETSs indicate that the model performed better in forecasting precipitation in the northeastern part of China without the influence of climatic background conditions.Comparison of the differences between the first period and the second period of the forecast shows that the precipitation amplitude in the ECMWF forecast shifted from slight underestimation to overestimation compared to that of CMPAS05,reducing the likelihood of missing extreme precipitation events.The improvement in ETS is mainly due to the reduction in bias and false alarm rates and,more importantly,an increase in the hit rate.From 2017 to 2022,the area coverage error of model precipitation forecast relative to observations showed a decreasing trend at different scales,while the FSS showed an increasing trend,with the highest FSS observed in 2021.The ETS followed a parabolic trend with increasing neighborhood radius,with the better ETS neighborhood radius generally being larger for moderate rain and heavy rain compared with light rain and torrential rain events.
基金supported by the Natural Science Foundation of Zhejiang Province(LY19A020001).
文摘With the increasing demand for electrical services,wind farm layout optimization has been one of the biggest challenges that we have to deal with.Despite the promising performance of the heuristic algorithm on the route network design problem,the expressive capability and search performance of the algorithm on multi-objective problems remain unexplored.In this paper,the wind farm layout optimization problem is defined.Then,a multi-objective algorithm based on Graph Neural Network(GNN)and Variable Neighborhood Search(VNS)algorithm is proposed.GNN provides the basis representations for the following search algorithm so that the expressiveness and search accuracy of the algorithm can be improved.The multi-objective VNS algorithm is put forward by combining it with the multi-objective optimization algorithm to solve the problem with multiple objectives.The proposed algorithm is applied to the 18-node simulation example to evaluate the feasibility and practicality of the developed optimization strategy.The experiment on the simulation example shows that the proposed algorithm yields a reduction of 6.1% in Point of Common Coupling(PCC)over the current state-of-the-art algorithm,which means that the proposed algorithm designs a layout that improves the quality of the power supply by 6.1%at the same cost.The ablation experiments show that the proposed algorithm improves the power quality by more than 8.6% and 7.8% compared to both the original VNS algorithm and the multi-objective VNS algorithm.
文摘Against the backdrop of the international political and economic configuration featuring that“the East is rising and the West is declining”,relations between China and its neighboring countries enjoy steady development in general.However,the return of the Cold War mentality,rampant protectionism and prominent security governance issues have seriously threatened peace and stability in China’s neighboring region.