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基于区间推理和AFS结构的模糊分类器
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作者 邱望仁 刘陶 刘晓东 《信息与控制》 CSCD 北大核心 2006年第5期651-656,661,共7页
在分析区间值模糊集理论和现有模糊分类器的基础上,提出两种分类器的算法,它们分别是建立在区间值推理和AFS结构上的.经Iris数据实验,证明第一种算法分类结果很好,后一算法不仅结果与前面的一样好,而且它还能处理一些描述模糊概念的数据... 在分析区间值模糊集理论和现有模糊分类器的基础上,提出两种分类器的算法,它们分别是建立在区间值推理和AFS结构上的.经Iris数据实验,证明第一种算法分类结果很好,后一算法不仅结果与前面的一样好,而且它还能处理一些描述模糊概念的数据库.这两种算法在分类实践中具有良好的应用前景.* 展开更多
关键词 区间值模糊集 模糊推理 模糊分类器 模糊匹配函数 afs结构
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基于相平面的车辆AFS与DYC可拓协调控制 被引量:4
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作者 周国忠 严运兵 +1 位作者 杨勇 彭文典 《武汉科技大学学报》 CAS 北大核心 2021年第2期146-153,共8页
为了提高汽车的操纵稳定性,弥补主动前轮转向(AFS)在轮胎侧向力饱和的情况下对车辆稳定性控制的不足,引入直接横摆力矩控制(DYC),设计了基于相平面的可拓协调控制系统,分为上、下两层。上层为AFS和DYC的功能协调层,以轮胎侧偏特性线性... 为了提高汽车的操纵稳定性,弥补主动前轮转向(AFS)在轮胎侧向力饱和的情况下对车辆稳定性控制的不足,引入直接横摆力矩控制(DYC),设计了基于相平面的可拓协调控制系统,分为上、下两层。上层为AFS和DYC的功能协调层,以轮胎侧偏特性线性极限和β相图稳定域边界作为依据来划分汽车行驶状态,对应于可拓集合中的经典域、可拓域和非域,运用可拓学理论求解关联度函数,并确定控制器间的协调权重;下层为主动前轮转向控制器和直接横摆力矩控制器,均采用粒子群算法优化PID控制参数。利用Simulink与CarSim软件搭建联合仿真试验平台,选用低附单移线工况和低附阶跃转向工况进行仿真验证。结果表明,本文所设计的可拓协调控制策略能有效弥补单一主动前轮转向控制的不足,改善车辆对参考轨迹的跟踪效果,并能降低质心侧偏角,保证了车辆的行驶稳定性。 展开更多
关键词 汽车操纵稳定性 可拓协调控制 主动前轮转向 直接横摆力矩控制 关联度函数 相平面
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AFS自动陀螺定位定向系统在地铁中的应用 被引量:1
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作者 王建 《工程勘察》 CSCD 北大核心 2006年第12期69-71,共3页
根据笔者的实践经验,本文介绍了AFS自动陀螺系统的组成、功能和作业步骤。实践证明,将其应用在地铁工程测量中,能够达到提高隧道贯通精度、大大提高作业效率及降低劳动强度等目的。
关键词 afs 自动陀螺仪 应用
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Functional Characteristics of Beijing Subway Stations Based on POI Data:Taking Beijing Metro Line 6 as An Example 被引量:1
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作者 SUN Shuai LIU Ting AI Jie 《Journal of Landscape Research》 2023年第3期27-30,共4页
Urban subway station is a key node related to urban social,political,economic and cultural activities.There are some differences in the location,function orientation,land use and flow characteristics of different type... Urban subway station is a key node related to urban social,political,economic and cultural activities.There are some differences in the location,function orientation,land use and flow characteristics of different types of stations in the city.This paper mainly used Tyson’s edge,kernel density analysis,chart analysis and other methods to classify the functional types of 412,393 POI data of 26 stations along Metro he results showed that the spatial distribution of Beijing Metro Line 6 was mainly divided into 3 categories,subway stations were divided into 4 categories.Among them,type A sites were divided into composite and single types,and the distribution characteristics of the 6 types of sites were quite different.Based on the qualitative and quantitative analysis of POI point data,this method can quickly classify and analyze the characteristics of stations along Line 6 in Beijing,which also has theoretical and practical value for the planning of urban subway lines. 展开更多
关键词 Urban functional areas Subway station POI data
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Service Functions of Private Community Health Stations in China: A Comparison Analysis with Government-sponsored Community Health Stations
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作者 侯万里 樊宏 +8 位作者 许静 王芳 柴云 徐汉成 李永斌 刘利群 王斌 金建强 卢祖洵 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2012年第2期159-166,共8页
In China, with the restructuring of health care system moving forward, private community health facilities have been playing a complementary but increasingly important role in providing public health and basic medical... In China, with the restructuring of health care system moving forward, private community health facilities have been playing a complementary but increasingly important role in providing public health and basic medical care services in urban areas. However, only limited evidence is available con-cerning the service functions of private community health facilities in China. The aim of this study was to explore the functions of private community health stations (PCHSs) to provide evidence-based rec-ommendations for policy-making and practice in the development of urban community health services systems. A total of 818 PCHSs and 4320 government-sponsored community health stations (GCHSs) located in 28 cities of China were investigated in 2008. The percentages of stations that provided health services and the annual workload per community health worker (CHW) were compared between the two types of institutions. The results showed that the percentages of PCHSs providing public health services were significantly higher than those of GCHSs (P<0.05); but no significant differences were found in the percentages of basic medical services providing between PCHSs and GCHSs (P>0.05). The annual workloads of all the public health services and basic medical services per CHW in PCHSs were lighter than those in GCHSs (P<0.05), except for resident health records establishment and health education materials distribution (P>0.05). At present, the GCHSs are still the mainstream in urban China, which will last for a long period in future. However, our findings showed that the annual workloads of CHWs in PCHSs were no heavier than those in GCHSs, and the PCHSs were willing to provide public health services. In view of current inadequacy of health resources in China, it is feasible to further develop PCHSs under the guidance of the government, given that PCHSs can perform the basic functions of community health services, which is useful for the formation of public-private partnerships (PPP) and the improvement of community health services. 展开更多
关键词 private community health stations government-sponsored community health stations services functions
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AFS-9X系列原子荧光仪软件操作功能的开发应用
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作者 辛若竹 吴鸣 +2 位作者 常晶红 彭永凯 马淑欣 《化学分析计量》 CAS 2013年第3期73-76,共4页
介绍AFS-9X系列原子荧光仪工作系统应用管理样品校正测试样品检测结果的软件操作方法。仪器可自动显示更接近于真值的校正值及试验的回收率,加强和完善了仪器对检测结果质量控制的功能,说明了软件操作中影响检测数据准确度的注意事项。
关键词 afs-9X系列 软件操作 质控功能 注意事项
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Function Analysis of Urban Rail Transit Smart Station
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作者 Can Chen 《Journal of Architectural Research and Development》 2023年第4期26-31,共6页
In order to make rail transit smart stations serve passengers better,the potential of smart stations should be optimized to reduce time cost,and relieve traffic congestion.In this paper,the construction of smart stati... In order to make rail transit smart stations serve passengers better,the potential of smart stations should be optimized to reduce time cost,and relieve traffic congestion.In this paper,the construction of smart stations based on the management experience of a subway station and the benefits of smart stations were analyzed and discussed.The construction of smart stations,as well as the key technologies for the construction of smart stations,will aid in the automation and intelligent management of subway stations. 展开更多
关键词 Urban rail transit Smart station function analysis
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Classification of Service Functions in the Life Circle of Beijing Subway Line 7
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作者 SUN Shuai XIANG Zixiong 《Journal of Landscape Research》 2024年第4期21-26,共6页
As a key node for the surrounding area,metro stations are closely connected with the surrounding urban space and develop cooperatively.Different types of metro stations have differences in land use and functional posi... As a key node for the surrounding area,metro stations are closely connected with the surrounding urban space and develop cooperatively.Different types of metro stations have differences in land use and functional positioning.This paper mainly used the methods of Tyson polygon,kernel density analysis and correlation analysis,based on POI data,to classify the stations of Beijing Metro Line 7.This paper made a detailed analysis of commercial subway stations,and analyzed the distribution characteristics of commercial metro stations on Line 7. 展开更多
关键词 POI data Kernel density analysis Correlation analysis function analysis around metro station
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Electromagnetic response function for the semi-annual variations estimated by the single-station method using the night-time values of the geomagnetic fields
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作者 陈伯舫 《Acta Seismologica Sinica(English Edition)》 CSCD 2000年第3期316-324,共9页
The geomagnetic night-time values were used to estimate the electromagnetic response function Q1 for half-year period. If the spatial structure of the source field can be described by the approximation, one can estim... The geomagnetic night-time values were used to estimate the electromagnetic response function Q1 for half-year period. If the spatial structure of the source field can be described by the approximation, one can estimate the Q1 value using the single-station Z/H method. This technique enables us to carry out regional deep gcomagnetic sounding by the method. The data used for analyses are geomagnetic night-time values for about, typically, 26 years from 5 good-quality stations and for several years from 34 stations distributed over the globe. The results indicate that the night-time values yield more reliable response estimates for half-year period compared to the usual estimates obtained from daily means. It implies that the approximation for the night-time fields holds good for the half-year period, but the daily means are not suitable for estimating the response function of the semi-annual variations by using the single-station method. Source field analyses for daily means data and night-time means data have also been carried out in this paper. 展开更多
关键词 geomagnetic night-time data semi-annual variations electromagnetic response functions single-station Z/H method
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AF-8B对小鼠机体抗疲劳作用的研究 被引量:1
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作者 郭唯 张培林 +2 位作者 张海艳 董建军 赵天增 《河南科学》 2005年第6期813-815,共3页
试验观察从天然植物中提取的黄酮醇苷类化合物AF-8B对小鼠机体是否有抗疲劳作用.方法通过小鼠负重游泳试验、肝糖原测定以及血乳酸测定对AF-8抗疲劳作用进行综合考察.结果AF-8B能显著延长小鼠负重游泳时间、增加小鼠肝糖原含量、减少小... 试验观察从天然植物中提取的黄酮醇苷类化合物AF-8B对小鼠机体是否有抗疲劳作用.方法通过小鼠负重游泳试验、肝糖原测定以及血乳酸测定对AF-8抗疲劳作用进行综合考察.结果AF-8B能显著延长小鼠负重游泳时间、增加小鼠肝糖原含量、减少小鼠血乳酸含量.结论AF-8B具有显著抗疲劳作用. 展开更多
关键词 功能食品 抗疲劳 黄酮醇苷 af-8B
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基于小目标类别注意力机制与特征融合的AF-ICNet非结构化场景语义分割方法 被引量:6
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作者 艾青林 张俊瑞 吴飞青 《光子学报》 EI CAS CSCD 北大核心 2023年第1期181-194,共14页
针对非结构化道路分割难度大、小目标检测精度较低等问题,构建基于小目标类别注意力机制与特征融合的AF-ICNet轻量级实时语义分割网络。采用空洞空间卷积池化金字塔融合不同尺度特征感受野以增强网络的全局感知能力。嵌入CA注意力机制,... 针对非结构化道路分割难度大、小目标检测精度较低等问题,构建基于小目标类别注意力机制与特征融合的AF-ICNet轻量级实时语义分割网络。采用空洞空间卷积池化金字塔融合不同尺度特征感受野以增强网络的全局感知能力。嵌入CA注意力机制,建立通道信息和空间位置信息以增强网络对非结构化道路小目标类别语义特征的提取能力。针对类别分布不均衡问题,改进权重交叉熵损失函数。利用AF-ICNet模型对Cityscapes与IDD数据集进行训练,在Cityscapes测试图像中分割的MIoU达到了71.5%,在IDD测试图像中分割的MIoU达到了62.5%。搭建实验测试系统进行实景测试,测试结果表明,AF-ICNet有效提升了非结构化道路及小目标类别的分割精度,并满足测试的实时性要求。 展开更多
关键词 小目标类别语义分割 af-ICNet CA注意力机制 空洞空间卷积池化金字塔 损失函数
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基于AFC数据挖掘的轨道交通站点分类研究 被引量:13
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作者 邓评心 郑长江 +1 位作者 马庚华 李锐 《华东交通大学学报》 2019年第2期77-82,共6页
轨道交通站点的分类对于研究不同类别站点的客流规律、周边土地利用情况以及发展趋势都有着重要影响。基于AFC数据,综合多种有效性指标确定分类数,采用主成分分析、k-means聚类、多元线性回归等方法,定性分析与定量分析相结合对站点进... 轨道交通站点的分类对于研究不同类别站点的客流规律、周边土地利用情况以及发展趋势都有着重要影响。基于AFC数据,综合多种有效性指标确定分类数,采用主成分分析、k-means聚类、多元线性回归等方法,定性分析与定量分析相结合对站点进行类别划分。将苏州轨道交通1、2号线共58个站点分为4类,为站点分类别后续研究以及轨道交通发展研究奠定基础。 展开更多
关键词 afC数据 站点功能定位 K-MEANS 回归分析
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基于CEEMDAN-AF和提升小波的发动机支撑信号去噪研究 被引量:2
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作者 顾中禹 靳鸿 崔建峰 《自动化与仪表》 2019年第5期5-9,共5页
针对某履带式车辆发动机支撑压力传感器信号由于工况复杂、环境恶劣所导致的信噪比低、有效信号被埋没等问题,该文提出了一种基于自适应白噪声的完整集成经验模态分解与自相关函数(CEEMDAN-AF)和提升小波的联合去噪方法。该方法首先对... 针对某履带式车辆发动机支撑压力传感器信号由于工况复杂、环境恶劣所导致的信噪比低、有效信号被埋没等问题,该文提出了一种基于自适应白噪声的完整集成经验模态分解与自相关函数(CEEMDAN-AF)和提升小波的联合去噪方法。该方法首先对信号进行CEEMDAN分解得到IMF分量,通过AF判别出IMF分量中噪声主导分量并对其进行提升小波去噪,最后进行数据重构得到去噪信号。通过实验仿真和实测压力传感器信号对比验证表明,该方法在信噪比和均方根误差方面具有优势,对实测压力传感器信号去噪效果明显。 展开更多
关键词 信号去噪 CEEMDAN 自相关函数 提升小波 发动机支撑 压力传感器
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利用行人路阻函数评估地铁站内AFC设备运营状况 被引量:2
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作者 邵远忠 邵巍跃 +1 位作者 张宁 徐文 《都市快轨交通》 北大核心 2013年第2期49-52,118,共5页
地铁站内AFC设备作为整个车站客流疏散的通行瓶颈,其运营状况关系到地铁线路乃至整个线网的运营状况。将BPR函数移植于地铁站内的行人交通流并对其进行线性改进,通过实际调研获取不同类型地铁站内与AFC设备处行人流相关的统计数据,并进... 地铁站内AFC设备作为整个车站客流疏散的通行瓶颈,其运营状况关系到地铁线路乃至整个线网的运营状况。将BPR函数移植于地铁站内的行人交通流并对其进行线性改进,通过实际调研获取不同类型地铁站内与AFC设备处行人流相关的统计数据,并进一步通过统计软件对调研数据进行拟合分析。研究表明,车站类型、设备数量以及设备布局对AFC设备运营状况具有重要影响,相关研究分析可为地铁站内AFC设备运营状况的分析与评估提供依据。 展开更多
关键词 城市轨道交通 地铁站 afC设备 行人路阻 函数 BPR
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A NOVEL ALGORITHM FOR SIDE PEAKS SUPPRESSION OF AMBIGUITY FUNCTION FOR PASSIVE RADAR BASED ON CHINESE DTTB SIGNAL 被引量:5
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作者 Li Jichuan Lu Xiaode Zhao Yaodong 《Journal of Electronics(China)》 2012年第6期485-492,共8页
The ambiguity function of Chinese standard Digital Television Terrestrial Broadcasting (DTTB) signals for passive radar contains one main peak and many side peaks. The side peaks may cause the false alarms. The relati... The ambiguity function of Chinese standard Digital Television Terrestrial Broadcasting (DTTB) signals for passive radar contains one main peak and many side peaks. The side peaks may cause the false alarms. The relative positions and the reasons for the side peaks are analyzed and a new algorithm for side peaks suppression is proposed in this paper. The algorithm, in consideration of the characteristics of the structure of the frame, can eliminate the side peaks completely in the valid Doppler observation interval by setting the reference signals to zero at equal intervals. Both the simulative and experimental results show that this algorithm can improve the performance of target detection of the passive radar based on DTTB signal. 展开更多
关键词 Passive radar Digital Television Terrestrial Broadcasting (DTTB) Ambiguity function (af) Side peaks suppression
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Kravchenko probabilityweight functions in problems of radar signals correlation processing 被引量:3
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作者 V F Kravchenko D V Churikov 《Journal of Measurement Science and Instrumentation》 CAS 2013年第3期231-237,共7页
In this report the combined method of correlation radar signal(RS)processing based on the theory of atomic functions(AF)is examined.Examples of using of new Kravchenko probability weight functions(WF)designs are prese... In this report the combined method of correlation radar signal(RS)processing based on the theory of atomic functions(AF)is examined.Examples of using of new Kravchenko probability weight functions(WF)designs are presented.Quality functional to estimate accuracy and efficiency of RS processing for concrete physical models is constructed.It is shown that the proposed approach significantly improves the quality of the coherent analysis of RS. 展开更多
关键词 radar signal (RS) atomic funtions af weight functions (WF)CLC number:TN911.7 Document code:AArticle ID:1674-8042(2013)03-0231-07
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The anomalous reactions of the geomagnetic horizontal field transfer functions before Tangshan earthquake
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作者 龚绍京 陈化然 +2 位作者 张翠芬 杨程君 马淑芹 《Acta Seismologica Sinica(English Edition)》 CSCD 1997年第1期60-69,共10页
We have collected the data of variometers in period from 1972 through 1984 at Changli and Baijiatuan stations. The results calculated from 19 groups of data show: 1) There are no significant anomalies of A... We have collected the data of variometers in period from 1972 through 1984 at Changli and Baijiatuan stations. The results calculated from 19 groups of data show: 1) There are no significant anomalies of A, B at Baijiatuan and that of B at Changli, but there are evident anomalous changes for A u, A v at Changli station. This result basically agrees to the a, b calculated using the method of measuring magnetograms, which demonstrates that the anomalies limited in the aftershock area and its neighbouring regions. 2) There are some changes of the inter station transfer functions of C u, C v, F u, F v before Tangshan earthquake, and the changes of the image parts C v, F v are more obvious, which is in agreement with the research results for Hualian earthquake. However, according to the results of Carlisle M =5.0 earthquake by Beamish(1982), the real parts F u, C u change more significantly. 展开更多
关键词 horizontal field inter station transfer functions underground electric structure abnormal field normal field
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On the problems concerned in“The subter-ranean electrical conductivity structure at the ChineseGreatWalStationonAntarctic(CG┐WSA)”byXiaopingZeng,YunfangLinandYuechenZhao
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作者 陈伯舫 《Acta Seismologica Sinica(English Edition)》 CSCD 1996年第3期143-147,共5页
By means of the Capon spectral analysis technique calculated the frequency response of the geomagnetic transfer functions for the Chinese Great Wall Station on Antarctic, and made a preliminary inference for the und... By means of the Capon spectral analysis technique calculated the frequency response of the geomagnetic transfer functions for the Chinese Great Wall Station on Antarctic, and made a preliminary inference for the underground electrical conductivity structure. In the present note, the writer considers that there are some problems concerned in their paper. Maybe it is worthwhile discussing these problems as below. 展开更多
关键词 the Chinese Great Wall station on Antarctic(CGWSA) transfer function.
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Multistatic radar analysis based on ambiguity function and Cramér-Rao lower bounds
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作者 雷鹏正 黄晓涛 《Journal of Central South University》 SCIE EI CAS 2014年第8期3092-3097,共6页
The primary goal of this work is to characterize the impact of weighting selection strategy and multistatic geometry on the multistatic radar performance. With the relationship between the multistatic ambiguity functi... The primary goal of this work is to characterize the impact of weighting selection strategy and multistatic geometry on the multistatic radar performance. With the relationship between the multistatic ambiguity function (AF) and the multistatie Cram6r-Rao lower bound (CRLB), the problem of calculating the multistatic AF and the multistatic CRLB as a performance metric for multistatic radar system is studied. Exactly, based on the proper selection of the system parameters, the multistatic radar performance can be significantly improved. The simulation results illustrate that the multistatic AF and the multistatic CRLB can serve as guidelines for future multistatic fusion rule development and multistatic radars deployment. 展开更多
关键词 ambiguity function af Cram6r-Rao lower bound (CRLB) multistatic radar
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Functional Characteristics of the Surrounding Area of Beijing Metro Line 5 Based on POI Data
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作者 SUN Shuai AI Jie LIU Ting 《Journal of Landscape Research》 2023年第2期27-31,38,共6页
As an important urban infrastructure,rail transit not only has transportation function,but also has a close connection and harmonious development with the surrounding urban space.Taking Beijing Metro Line 5 as an exam... As an important urban infrastructure,rail transit not only has transportation function,but also has a close connection and harmonious development with the surrounding urban space.Taking Beijing Metro Line 5 as an example,each station of Beijing Metro Line 5 was analyzed by GIS software and Echarts chart based on POI data.The functions of subway site type were divided into main function,secondary function and no significant function,and various types of sites within the main functional characteristics of urban functions were discussed in details.The paper presents a new method for identifying urban functional features,which can be applied to not only other metro stations in Beijing but also the same type of cities.Moreover,it lays a foundation for the research of rail transit subway stations and their related researches. 展开更多
关键词 POI Subway station Urban function
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