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Weak influence of natural vegetation in urban green spaces compared to agricultural ecosystems on House Martin populations:Insights from nationwide citizen science data in the Czech Republic
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作者 Denisa Dvorakova Jan Sipos Josef Suchomel 《Avian Research》 SCIE CSCD 2024年第2期139-146,共8页
The House Martin(Delichon urbicum)is a common farmland bird species in the European landscape,yet its population numbers are currently in decline.However,it is not yet sufficiently explained why this long-term decline... The House Martin(Delichon urbicum)is a common farmland bird species in the European landscape,yet its population numbers are currently in decline.However,it is not yet sufficiently explained why this long-term decline occurs.To fill this gap in our knowledge,we investigated how land cover composition affects the abundance of House Martins on the landscape scale by using nationwide citizen science data.Utilizing a generalised linear mixed-effect model(GLMM),we evaluated 12,094 records from the Czech Republic spanning 2009-2017.Our analysis underscores the significance of land cover type in shaping House Martin abundance.More specifically,our results indicate that within agricultural land covers“naturally managed arable lands”exhibited significant positive effect,while forests,orchards,and vineyards were deemed less favourable for House Martin populations.Within urban land covers,we found a clear distinction in the impact on House Martin populations,with a positive effect observed in urban infrastructure,development areas,and post-industrial sites(i.e.,UrbanAreas),while an indifferent impact was noted within urban green spaces and landscaped areas(i.e.,GreenUrban).Notably,our findings suggest that the simple spatial,age,and species structure typical of forests in Europe,and similarly,the uniform structure of parks and gardens,may be responsible for the decline in the abundance of the House Martin.We advocate for the preservation or enhancement of urban greenery,expansion of natural vegetation in rural areas and adoption of ecological management practices in orchards and vineyards to mitigate further declines in House Martin populations. 展开更多
关键词 Citizen science Habitat preferences House Martin Species distribution urban and suburban landscape
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Microspace Revitalization Design around Xihuangcun Railway Station from the Perspective of Urban Renewal
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作者 WU Di XU Fang 《Journal of Landscape Research》 2024年第1期31-34,共4页
Railways within the city carry the historical memory of urban development and are important industrial heritage resources.However,with urban development and changes in transportation functions,railways lose their orig... Railways within the city carry the historical memory of urban development and are important industrial heritage resources.However,with urban development and changes in transportation functions,railways lose their original application value and are gradually left unused or even abandoned,affecting the vitality of the region.Taking the space around Xihuangcun Railway Station as the research object,the public activity space on both sides of the railway is reshaped through five strategies:function revitalization,traffic revitalization,heritage revitalization,spatial revitalization,and landscape revitalization,and the grey area of the city is transformed into a vibrant development zone of the city. 展开更多
关键词 urban renewal Heritage rejuvenation Abandoned railway Microspace
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Comparison of Ozone and PM2.5 Concentrations over Urban,Suburban,and Background Sites in China 被引量:14
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作者 Lan GAO Xu YUE +4 位作者 Xiaoyan MENG Li DU Yadong LEI Chenguang TIAN Liang QIU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2020年第12期1297-1309,I0001-I0004,共17页
Surface ozone(O3)and fine particulate matter(PM2.5)are dominant air pollutants in China.Concentrations of these pollutants can show significant differences between urban and nonurban areas.However,such contrast has ne... Surface ozone(O3)and fine particulate matter(PM2.5)are dominant air pollutants in China.Concentrations of these pollutants can show significant differences between urban and nonurban areas.However,such contrast has never been explored on the country level.This study investigates the spatiotemporal characteristics of urban-to-suburban and urban-tobackground difference for O3(Δ[O3])and PM2.5(Δ[PM2.5])concentrations in China using monitoring data from 1171 urban,110 suburban,and 15 background sites built by the China National Environmental Monitoring Center(CNEMC).On the annual mean basis,the urban-to-suburbanΔ[O3]is−3.7 ppbv in Beijing-Tianjin-Hebei,1.0 ppbv in the Yangtze River Delta,−3.5 ppbv in the Pearl River Delta,and−3.8 ppbv in the Sichuan Basin.On the contrary,the urban-to-suburbanΔ[PM2.5]is 15.8,−0.3,3.5 and 2.4μg m^−3 in those areas,respectively.The urban-to-suburban contrast is more significant in winter for bothΔ[O3]andΔ[PM2.5].In eastern China,urban-to-background differences are also moderate during summer,with−5.1 to 6.8 ppbv forΔ[O3]and−0.1 to 22.5μg m^−3 forΔ[PM2.5].However,such contrasts are much larger in winter,with−22.2 to 5.5 ppbv forΔ[O3]and 3.1 to 82.3μg m^−3 forΔ[PM2.5].Since the urban region accounts for only 2%of the whole country’s area,the urban-dominant air quality data from the CNEMC network may overestimate winter[PM2.5]but underestimate winter[O3]over the vast domain of China.The study suggests that the CNEMC monitoring data should be used with caution for evaluating chemical models and assessing ecosystem health,which require more data outside urban areas. 展开更多
关键词 OZONE PM2.5 urban suburban BACKGROUND
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Suburbanization and Subcentering of Population in Beijing Metropolitan Area:A Nonparametric Analysis 被引量:3
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作者 SUN Tieshan HAN Zhenhai +1 位作者 WANG Lanlan LI Guoping 《Chinese Geographical Science》 SCIE CSCD 2012年第4期472-482,共11页
This study focuses on the suburbanization and subcentering of population and examines the nature of spatial restructuring in terms of the population distribution in the Beijing metropolitan area.Instead of the classic... This study focuses on the suburbanization and subcentering of population and examines the nature of spatial restructuring in terms of the population distribution in the Beijing metropolitan area.Instead of the classic density function approach,we employ the nonparametric analysis to characterize the spatial pattern of population densities in the Beijing metropolitan area and identify the suburban subcenters.Our findings suggest that the population has spread with rapid urban growth in the Beijing metropolitan area,and the compact urban form has been replaced by a more dispersed polycentric spatial distribution.However,compared with the decentralization of western cities,the spatial extent of the decentralization of population in the Beijing metropolitan area is quite limited.The rapid growth of population in the near suburbs has expedited the sprawl of the central city,with a larger central agglomeration of population dominating the metropolitan area.In this sense,the spatial pattern of the Beijing metropolitan area is still characterized by the continuous compactness.However,our findings do provide the evidence that the city has been turning to a polycentric structure.We find significant population subcenters have emerged in the suburbs of Beijing since the 1980s.But the polycentricity emerged in the Beijing metropolitan area is very different by nature from that observed in Western cities.The subcenters emerged are adherent to the development scheme planned for the city,so it can be referred to as the so called 'planned polycentricity'. 展开更多
关键词 suburbanIZATION population subcenters POLYCENTRICITY urban spatial structure Beijing metropolitan area
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Impacts of Suburbanization on Urban Eco-environment of Xi'an in China
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作者 Li Junli Cao Mingming 《Chinese Journal of Population,Resources and Environment》 2011年第4期90-94,共5页
Suburbanization in large cities is an important phenomenon in the process of urbanization development in China in recent decades,which plays a very important role in promoting city development,whereas some side effect... Suburbanization in large cities is an important phenomenon in the process of urbanization development in China in recent decades,which plays a very important role in promoting city development,whereas some side effects on the eco-environment appeared at the same time.This paper,taking Xi'an City in China as a case study site,analyzed the features of population suburbanization and industry suburbanization and pointed out the impacts of suburbanization on urban eco-environment.Based on the research,suggestions of countermeasures for urban planning and municipal management of Xi'an City in protecting urban eco-environment and conserving natural ecology were put forward in the end. 展开更多
关键词 suburbanIZATION urban environment ecological impacts COUNTERMEASURES Xi'an City
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Expansion Strategy of Agricultural Industrial Chain of Suburban Villages and Towns in the Process of Urbanization——A Case Study of Yongle Town in Nanming District of Guiyang City
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作者 ZHU Li ZHU Jing 《Asian Agricultural Research》 2011年第6期118-122,134,共6页
On the basis of introducing the connotation of agricultural industrial chain, taking Yongle Town in Nanming District of Guiyang City as an example, this paper analyzes the advantages and constraint factors of the subu... On the basis of introducing the connotation of agricultural industrial chain, taking Yongle Town in Nanming District of Guiyang City as an example, this paper analyzes the advantages and constraint factors of the suburban villages and towns in the process of expanding agricultural industrial chain in the context of urbanization. Corresponding strategies of expanding the agricultural industrial chain of Yongle Town in the process of urbanization as follows: vigorously develop the leading enterprises; strengthen the construction of farmers' specialized cooperatives and agricultural associations; build and perfect agricultural industrial chain organizations; set up the public information platform; rely on the food industrial park to propel the deep processing of agricultural products; vigorously develop the logistics of agricultural products; promote the development of operation model of "brand+ standard+ scale"; vigorously develop ecology-oriented rural tourism; give full play to the functional role of the government. 展开更多
关键词 urbanIZATION suburban villages and towns Income increase of farmers Expansion of agricultural industry chain China
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The Mechanism Behind Urban Population Growth and Shrinkage from the Perspective of Urban Network Externalities
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作者 ZHOU Ying ZHENG Wensheng +2 位作者 WANG Xiaofang XIONG Yajun WANG Xuzheng 《Chinese Geographical Science》 SCIE CSCD 2023年第2期189-204,共16页
Urban shrinkage is a global phenomenon,and it will coexist with urban growth for many years.At the same time,the network connection between cities continuously improved due to the construction of the transportation an... Urban shrinkage is a global phenomenon,and it will coexist with urban growth for many years.At the same time,the network connection between cities continuously improved due to the construction of the transportation and information networks.However,the relationship between urban network externalities and urban population growth/shrinkage remains unclear.Therefore,based on high-speed railway(HSR)flow data,a spatial econometric model is used to explore the mechanism behind urban population growth and shrinkage from the perspective of network externalities in China.The results indicate that:1)the urban network experiences a certain clubbing effect.Growing cities that are strongly connected are concentrated along China’s main railway lines and the southeastern coastal areas,while shrinking cities that are weakly connected are distributed at the periphery of the network.2)Moreover,the network externality disregards spatial distance and together with the agglomeration externality influences the growth and shrinking of cities.3)Urban economic development still promotes the development of Chinese cities.However,the improvement of the urban economy has a negative cross-regional spillover effect on neighboring cities due to urban competition.4)Lastly,Local spillovers of urban network externalities are positive,while cross-regional ones are negative.Consequently,the government needs to promote the construction of multi-dimensional network connections between cities to promote cities’sustainable development.This study reveals the relationship between urban network externalities and urban development,enriches the theories of network externalities and urban growth/shrinkage,and provides a reference for regional coordinated development. 展开更多
关键词 urban growth/shrinkage urban networks network externality high-speed railway(HSR) China
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Safety and Quality Control Management Strategy for Urban Railway Engineering Construction
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作者 Tao Yuan 《Journal of World Architecture》 2023年第2期30-35,共6页
The safety management of urban railway engineering construction involves many different aspects and a wide scope,playing an important role in guaranteeing the safety of construction projects.Management agencies have m... The safety management of urban railway engineering construction involves many different aspects and a wide scope,playing an important role in guaranteeing the safety of construction projects.Management agencies have more stringent requirements on the quality of railway construction.The overall quality of a construction project should meet the construction requirements before the project can be carried out.In this article,the problems in the actual work of the entire life cycle of safety management are explained,and the lessons and experience pertaining to the safety and quality of urban railway construction projects are discussed.The purpose of this paper is to provide references for the management of urban railway construction. 展开更多
关键词 urban railway SAFETY Quality management
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Fundamental Ideas and Basic Concepts of HSR Route Selection in Complicated Urban Areas
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作者 WANG Huihuang ZHANG Yiran(Translated) 《Chinese Railways》 2023年第2期53-60,共8页
Up till now,no systematic studies on railway route selection in urban areas,HSR route selection in particular,have been taken in China.Based on the Shenzhen Railway Terminal Project and the Shenzhen-Shanwei Railway Pr... Up till now,no systematic studies on railway route selection in urban areas,HSR route selection in particular,have been taken in China.Based on the Shenzhen Railway Terminal Project and the Shenzhen-Shanwei Railway Project,research on HSR route selection in complicated urban areas has been conducted.An optimal route selection plan is determined after studying the local geological and environmental conditions and the complexity of tunnel construction.The research concludes that there are four major concerns in HSR route selection:the match between the new route and the urban planning,the potential economic return for the massive investment,the likely impacts of land expropriation on social stability,and the best synthesis of multiple controlling factors to meet the HSR standard.Moreover,six principles should be followed in railway route selection in complicated urban areas:the new route should be in alignment with the railway deployment;the route should align with the existing passage as much as possible;extensive analysis and in-depth demonstrations should be done to find the most appropriate combination of open and hidden excavation in tunnel construction;geological conditions and tunnel construction complexities are among the priorities;environmental sensitive sites and environmental vibration noise should be avoided as much as possible;special attention should be paid to the relocation of the power supply,television and communication facilities and the rearrangement of tubes and wires. 展开更多
关键词 high speed railway(HSR) complicated urban areas route selection railway network layout
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超级中学垄断与城市内顶尖大学入学机会区域差异——基于北京市的实证研究
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作者 吴宇川 郭丛斌 《北京社会科学》 CSSCI 北大核心 2024年第8期103-114,共12页
超级中学的发展壮大可能加剧城市内部顶尖大学入学机会的区域差异,不利于大型城市引导人口向郊区流动。基于对某顶尖大学A北京生源调查数据(2001—2021年)的分析发现,顶尖大学入学机会在北京市存在着明显的城郊差异,位于城区的超级中学... 超级中学的发展壮大可能加剧城市内部顶尖大学入学机会的区域差异,不利于大型城市引导人口向郊区流动。基于对某顶尖大学A北京生源调查数据(2001—2021年)的分析发现,顶尖大学入学机会在北京市存在着明显的城郊差异,位于城区的超级中学与首位中学近年来分别垄断了A大学约40%与超过20%的生源;超级中学垄断降低了北京市一般高中学生的顶尖大学入学机会,但这种负面影响主要表现为对郊区一般高中学生顶尖大学入学可能性、顶尖大学生源密度及相对录取排名的冲击,城区一般高中所受影响并不明显。因此应该增加郊区优质教育资源投入,强化市级政府的资源统筹力度,同时也需要扩大优质高中的资源覆盖、加强郊区教师队伍建设、优化高中学校规划布局。 展开更多
关键词 超级中学 顶尖大学 入学机会 城郊差异
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既有铁路开行市域(郊)列车开行方案优化
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作者 周波 宋唯维 陈聪聪 《铁道工程学报》 EI CSCD 北大核心 2024年第10期90-96,共7页
研究目的:在利用既有铁路资源发展市域(郊)铁路的背景下,本文研究旨在提高市域(郊)铁路的运营效率,以满足乘客的出行需求。通过分析不同到达模式下的乘客行为,提出一种适应混合到达模式的市域(郊)客流分配方式。基于“线路国有、国铁与... 研究目的:在利用既有铁路资源发展市域(郊)铁路的背景下,本文研究旨在提高市域(郊)铁路的运营效率,以满足乘客的出行需求。通过分析不同到达模式下的乘客行为,提出一种适应混合到达模式的市域(郊)客流分配方式。基于“线路国有、国铁与地方共营”管理模式,构建一个多目标优化模型,综合考虑乘客出行时间、运营成本和地方政府成本,并采用遗传粒子群优化算法求解,优化列车开行方案。研究结论:(1)通过对某条市域(郊)铁路线路早高峰时段客流数据的实证分析表明,构建的市域(郊)列车开行方案优化模型能够显著提高运营效率;(2)该模型早高峰时段缩短了乘客总旅行时间34.8%,降低了铁路局运营成本10.2%,减少地方政府成本11.5%,并节省了10%的车辆购置费用;(3)本研究成果可为利用既有铁路开行市域(郊)列车的项目规划决策和运营优化提供参考。 展开更多
关键词 铁路运输 既有铁路 市域(郊)铁路 混合到达模式 列车开行方案 优化模型
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基于互联互通的市域铁路网络节点模式选择
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作者 余攀 《铁道工程学报》 EI CSCD 北大核心 2024年第4期1-6,12,共7页
研究目的:采用系统性方法探讨互联互通条件下市域铁路网络节点模式的选择方法,以上海市域铁路网络为例,旨在实现市域铁路网络的高效运行和区域的有机连接。本文研究集中于互联互通节点的功能定位、枢纽等级、位置选择及其与近沪城市的... 研究目的:采用系统性方法探讨互联互通条件下市域铁路网络节点模式的选择方法,以上海市域铁路网络为例,旨在实现市域铁路网络的高效运行和区域的有机连接。本文研究集中于互联互通节点的功能定位、枢纽等级、位置选择及其与近沪城市的有效衔接,以期提供一种优化市域铁路网络规划和建设的科学方法。研究结论:(1)互联互通节点的合理选择和布局对于提升市域铁路网络的运行效率和区域连接性具有决定性意义;(2)互联互通节点的功能定位、枢纽等级和位置选择是实现市域铁路网络高效运行的关键因素;(3)通过系统性研究和分析上海市域铁路网络,提出的节点模式选择方法可为其他城市的市域铁路规划和建设提供参考。 展开更多
关键词 铁路运输 市域铁路 互联互通 节点模式选择 网络规划
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桐庐舒羽山房设计——杭州城乡融合互促中的近郊乡村建设案例
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作者 贺勇 陈相权 陈钰凡 《城市设计》 2024年第2期44-53,共10页
一个好的建筑应该成为触媒,激活当地的文化与产业。本文以舒羽山房为典型案例,将其置于城乡融合的视野之下,探讨了经济发达地区的近郊乡村如何通过产业、人才、事件、营建等各方面的相互促进,持续提升当地的经济发展与人居环境水平,推... 一个好的建筑应该成为触媒,激活当地的文化与产业。本文以舒羽山房为典型案例,将其置于城乡融合的视野之下,探讨了经济发达地区的近郊乡村如何通过产业、人才、事件、营建等各方面的相互促进,持续提升当地的经济发展与人居环境水平,推进深度城乡融合与共同富裕。 展开更多
关键词 舒羽山房 近郊乡村 城乡融合 营建策略
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人户分离变迁视角的大城市郊区化与人口结构再分布效应研究--基于南京市的实证
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作者 陈浩 陈友华 陈昭 《人口与社会》 2024年第2期40-53,共14页
人户分离人口是城市流动型人口的主要构成部分,其特征及空间分布变迁为认识大城市郊区化趋势提供了重要视角。近20年来,南京市人户分离人口规模增长迅速,占常住人口比重逐渐提高,其中市内人户分离人口占总人户分离人口的比重显著提高,... 人户分离人口是城市流动型人口的主要构成部分,其特征及空间分布变迁为认识大城市郊区化趋势提供了重要视角。近20年来,南京市人户分离人口规模增长迅速,占常住人口比重逐渐提高,其中市内人户分离人口占总人户分离人口的比重显著提高,其人口学特征呈现高学历化和大龄化趋势,其空间分布从核心区集聚向近郊区集聚转变。基于以上变迁特征,重新认识了南京城市郊区化的进程及其程度,发现:(1)2000—2010年期间,南京经历了核心区和近郊区人口普遍增长的快速城市化阶段,外来流动人口是此时期近郊区人口增长的主要来源;(2)2010—2020年期间,南京进入大规模城市郊区化阶段,核心区人口减少而近郊区人口集聚度显著增强,市内人户分离人口取代外来流动人口成为近郊区人口增长的主要来源;(3)2020年,南京的近郊区常住人口人户分离率高达54.4%,表明南京仍处于“迁居不迁户”的“半郊区化”状态,近郊区并未成长为相对独立于核心区、功能相对完整的综合性城区。郊区化带来了不均衡的人口结构再分布效应,要关注和积极应对核心区人口流失与人口结构衰退过快、近郊区“人户分离率”过高和远郊区人口老龄化持续加深等问题。 展开更多
关键词 大城市 人户分离 郊区化 人口普查 人口结构再分布 城市更新
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都市圈市域(郊)铁路创新发展策略研究
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作者 刘建红 陈望桂 《现代城市轨道交通》 2024年第8期1-5,共5页
市域(郊)铁路是建设“轨道上的都市圈”、支撑都市圈高质量发展的重要抓手。目前,我国市域(郊)铁路建设已进入加速发展的机遇期。在此背景下,文章梳理总结国外都市圈市域(郊)铁路发展经验及特征,剖析我国都市圈市域(郊)铁路发展现状及问... 市域(郊)铁路是建设“轨道上的都市圈”、支撑都市圈高质量发展的重要抓手。目前,我国市域(郊)铁路建设已进入加速发展的机遇期。在此背景下,文章梳理总结国外都市圈市域(郊)铁路发展经验及特征,剖析我国都市圈市域(郊)铁路发展现状及问题,并从理念创新、机制创新、建设创新及运管创新4个方面提出都市圈市域(郊)铁路创新发展策略建议,以期为促进其高质量、可持续发展提供参考和借鉴。 展开更多
关键词 市域(郊)铁路 都市圈 创新 发展 策略
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面向客流的市域与城轨贯通运营下快慢车开行方案优化
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作者 任艾 孟令云 +2 位作者 王义惠 黄雯铮 任苒 《北京交通大学学报》 CAS CSCD 北大核心 2024年第4期153-163,共11页
为顺应当前市域铁路与城轨线路贯通运营的发展趋势,基于市域与城市轨道交通线路终点对接的衔接形式,市域铁路开行快慢车,城轨开行站站停列车的运营模式,通过路径客流分配,对贯通运营条件下列车开行方案进行优化.以乘客出行成本及企业运... 为顺应当前市域铁路与城轨线路贯通运营的发展趋势,基于市域与城市轨道交通线路终点对接的衔接形式,市域铁路开行快慢车,城轨开行站站停列车的运营模式,通过路径客流分配,对贯通运营条件下列车开行方案进行优化.以乘客出行成本及企业运营成本最小化为目标,考虑客流出行需求、线路通过能力等约束构建双目标非线性整数规划模型,并设计遗传算法进行求解.结合重庆轨道交通5号线与江跳线,从市域与城轨本线及跨线客流出行时间、列车停站及运行成本两方面,对换乘、贯通运营及快慢车等不同运营模式组合下列车开行方案进行对比分析,验证模型的有效性.研究结果表明:较换乘衔接模式,市域铁路与城市轨道交通贯通运营条件下开行快慢车的运营模式下的乘客出行时间降低了2.92%,企业总运营成本降低了4.88%;该模式适用于跨线出行需求较大的线路,满足跨线乘客从郊区至中心城区的快速出行需求.研究成果可以从运输组织层面为市域铁路与城市轨道交通的高效融合提供理论支持. 展开更多
关键词 列车开行方案 市域铁路 城市轨道交通 贯通运营 快慢车
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城郊融合类村庄规划编制思路与实践
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作者 曾献君 林伟伟 +2 位作者 王世福 彭冲 吴俐颖 《规划师》 CSSCI 北大核心 2024年第5期114-122,共9页
城郊融合类村庄具有向城市转型的条件,但在我国进入城镇化中后期后,其转型时间、转型程度均存在较大的不确定性。在现有的国土空间规划体系下,根据城镇开发边界划定在高度城乡一体化区域推进控制性详细规划和村庄规划两类详细规划编制... 城郊融合类村庄具有向城市转型的条件,但在我国进入城镇化中后期后,其转型时间、转型程度均存在较大的不确定性。在现有的国土空间规划体系下,根据城镇开发边界划定在高度城乡一体化区域推进控制性详细规划和村庄规划两类详细规划编制已经难以应对空间发展的不确定性。通过分析城郊融合类村庄的特征、问题和发展趋势,阐述了村庄规划编制内涵的转变,提出了城郊融合类村庄规划编制的思路。以福建省惠安县崇武镇五峰村为例,结合其现状特征及发展问题,将村庄空间进一步细化为城镇功能区、城乡协调发展区、乡村功能区,探索不同用途管制下控制性详细规划、村庄规划联合编制的技术及成果表达形式,并提出该类地区详细规划一体化编制的路径,为优化城郊融合类村庄的规划编制技术、提升乡村空间治理能力提供参考和借鉴。 展开更多
关键词 城乡融合 城郊融合类村庄 村庄规划 国土空间规划 编制技术
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新建市域(郊)铁路经济性现状分析及对策研究 被引量:2
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作者 颜燕舞 《现代城市轨道交通》 2024年第1期131-135,共5页
随着我国城镇化的快速推进及重点城市都市圈的成型,市域(郊)铁路迎来了黄金发展期。为降低新建市域(郊)铁路建设及运营成本,实现市域(郊)铁路健康、可持续发展,文章通过对国内新建市域(郊)铁路经济性现状进行调研和分析,明确当前新建市... 随着我国城镇化的快速推进及重点城市都市圈的成型,市域(郊)铁路迎来了黄金发展期。为降低新建市域(郊)铁路建设及运营成本,实现市域(郊)铁路健康、可持续发展,文章通过对国内新建市域(郊)铁路经济性现状进行调研和分析,明确当前新建市域(郊)铁路存在的技术标准不完善、工程投资大、运营成本高等问题;再结合相关政策要求,从系统规划、设计建设、运营管理等方面,提出降低新建市域(郊)铁路建设及运营成本、提高经营效益的对策及建议,以期为国内新建市域(郊)铁路的规划、设计、运营管理提供参考和借鉴。 展开更多
关键词 市域(郊)铁路 经济性 现状分析 对策
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城市空中交通动态空域垂直起降飞行器路径优化
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作者 周航 赵风旸 胡小兵 《交通运输系统工程与信息》 EI CSCD 北大核心 2024年第5期295-308,共14页
针对目前城市空中交通动态空域航线优化方法难以保证最优性和计算效率上不足,以及对市区与市郊混合运行场景覆盖的缺陷,首先,提出一种适用于市郊和市区运行的城郊结合路网构建方法;其次,基于电动垂直起降飞行器(eVTOL)飞行动力学模型,... 针对目前城市空中交通动态空域航线优化方法难以保证最优性和计算效率上不足,以及对市区与市郊混合运行场景覆盖的缺陷,首先,提出一种适用于市郊和市区运行的城郊结合路网构建方法;其次,基于电动垂直起降飞行器(eVTOL)飞行动力学模型,提出准确的eVTOL功率消耗模型优化飞行路径;最后,基于涟漪扩散算法(RSA)提出适用于动态空域中的动态加权路网(RSA-DWRN)算法。通过构建包含时变气流和障碍区影响的城郊结合路网结构,以优化路径耗电量、飞行时间、计算时间和匹配度为指标,比较RSA-DWRN和传统动态路径优化算法DPO-A*在5种场景下600次实验优化效果。仿真结果表明:RSA-DWRN算法在4类指标下效果最好,且当动态空域环境因素越复杂时,RSA-DWRN表现越优;当空域中存在移动障碍物时,DPO-A*算法无法预测其运动轨迹且需频繁更新路网状态,大量提高了路径规划计算成本,而RSA-DWRN算法在相同情景下与动态环境变化过程协同进化,得到同时保证优化结果和计算效率的最优解。 展开更多
关键词 航空运输 城郊结合路网 涟漪扩散算法 电动垂直起降飞行器 动态空域 路径优化
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城际铁路和市域(郊)铁路高质量发展对策研究 被引量:1
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作者 张国华 欧心泉 李娟 《现代城市轨道交通》 2024年第3期1-5,共5页
加快城际铁路和市域(郊)铁路建设是当前我国新型城镇化的重点任务之一,在补齐区域综合交通短板、推动区域协调发展、培育发展新动能等方面发挥着重要作用。为推动城际铁路和市域(郊)铁路高质量发展,文章在深刻剖析其目前经济效益不理想... 加快城际铁路和市域(郊)铁路建设是当前我国新型城镇化的重点任务之一,在补齐区域综合交通短板、推动区域协调发展、培育发展新动能等方面发挥着重要作用。为推动城际铁路和市域(郊)铁路高质量发展,文章在深刻剖析其目前经济效益不理想、重复建设、地方政府财政补贴压力加剧等“内卷化”问题及产生原因的基础上,梳理出突破“内卷化”的发展思路,即重谋划、转方式、聚合力,并围绕规划、土地、投融资、商业模式等重点领域提出深化改革的对策及建议,以期加强长效机制建设,推动城际铁路和市域(郊)铁路步入更加可持续的发展轨道。 展开更多
关键词 城际铁路 市域(郊)铁路 高质量发展 对策 内卷化
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