Here, we administered repeated-pulse transcranial magnetic stimulation to healthy people at the left Guangming (GB37) and a mock point, and calculated the sample entropy of electroencephalo- gram signals using nonli...Here, we administered repeated-pulse transcranial magnetic stimulation to healthy people at the left Guangming (GB37) and a mock point, and calculated the sample entropy of electroencephalo- gram signals using nonlinear dynamics. Additionally, we compared electroencephalogram sample entropy of signals in response to visual stimulation before, during, and after repeated-pulse tran- scranial magnetic stimulation at the Guangming. Results showed that electroencephalogram sample entropy at left (F3) and right (FP2) frontal electrodes were significantly different depending on where the magnetic stimulation was administered. Additionally, compared with the mock point, electroencephalogram sample entropy was higher after stimulating the Guangming point. When visual stimulation at Guangming was given before repeated-pulse transcranial magnetic stimula- tion, significant differences in sample entropy were found at five electrodes (C3, Cz, C4, P3, T8) in parietal cortex, the central gyrus, and the right temporal region compared with when it was given after repeated-pulse transcranial magnetic stimulation, indicating that repeated-pulse transcranial magnetic stimulation at Guangming can affect visual function. Analysis of electroencephalogram revealed that when visual stimulation preceded repeated pulse transcranial magnetic stimulation, sample entropy values were higher at the C3, C4, and P3 electrodes and lower at the Cz and T8 electrodes than visual stimulation followed preceded repeated pulse transcranial magnetic stimula- tion. The findings indicate that repeated-pulse transcranial magnetic stimulation at the Guangming evokes different patterns of electroencephalogram signals than repeated-pulse transcranial mag- netic stimulation at other nearby points on the body surface, and that repeated-pulse transcranial magnetic stimulation at the Guangrning is associated with changes in the complexity of visually evoked electroencephalogram signals in parietal regions, central gyrus, and temporal regions.展开更多
In recent years,decision support systems(DSSs)have successfully deployed ontologies in their architecture.The result of such a use is information systems that assist users and organizations in semi-structured decision...In recent years,decision support systems(DSSs)have successfully deployed ontologies in their architecture.The result of such a use is information systems that assist users and organizations in semi-structured decision-making activities.Visitors from throughout Iran travel to different cities and regions every year,and they need help making their choices.Some of these tourists are unable to visit the beautiful areas of the destination city due to a lack of awareness.In this study,we design an ontology-based spatial DSS to find entertainment and tourism centers in Arak,Iran.The objective is to provide users with recommendations appropriate for the location,time,age group,type of activity,and other factors.In this model,the demands and concerns of tourists have been managed by creating a domain Web Ontology Language(OWL)for entertainment centers as a knowledge base in the Protégéenvironment.The developed webbased DSS operates on a client-server architecture using technologies such as Werkzeug and Flask.As a result,it makes it possible to ontology reasoning based on the HermiT engine to choose the right center and conduct a semantic search on classes related to the appropriate point of interest.The main distinction between the proposed methodology and the previous studies on spatial DSS is that criteria are object properties in an ontology.Therefore,decision support relies on real-time reasoning rather than transforming criteria into geospatial layers.The evaluation results confirmed efficient interaction with this system,purposeful information retrieval,and rapid decision-making process.The results also indicated that searching for a POI(point of interest)in the study area using the developed system is at least 30%more successful than a search engine or social media.Moreover,to overcome the cold start problem,the proposed technique might be utilized in conjunction with the POI recommender systems.展开更多
长春市是国家新型城镇化综合试点城市,识别长春市中心城区功能,针对当前存在的问题提出对策建议,对城市空间的优化与协调具有重要意义。以兴趣点(Point of Interest,POI)数据及开放街道地图(Open Street Map,OSM)数据为基础,结合核密度...长春市是国家新型城镇化综合试点城市,识别长春市中心城区功能,针对当前存在的问题提出对策建议,对城市空间的优化与协调具有重要意义。以兴趣点(Point of Interest,POI)数据及开放街道地图(Open Street Map,OSM)数据为基础,结合核密度分析、实地调查验证等方法,识别长春市中心城区城市功能类型。结果表明:单一功能区中,商业功能区数量最多,居住功能区最少;主导—混合功能区中的商业主导功能区及交通主导功能区形成对商业聚集区与轨道交通系统的重要补充;细分—混合功能区特征显示功能混合程度从市中心向周边逐渐加大。经验证,城市功能识别结果符合长春市实际,由此提出对策建议:未来长春市中心城区应注重多中心发展格局,并加强绿地空间和公共服务设施建设。展开更多
兴趣点(point of interest,POI)推荐可以缓解用户选择困难问题并提高位置服务商、商家的收益,是位置社交网络的研究热点之一。在已有的综述中缺乏数据问题对策的梳理、前沿算法的更新、算法性能对比实验等内容。因此对这一领域的研究进...兴趣点(point of interest,POI)推荐可以缓解用户选择困难问题并提高位置服务商、商家的收益,是位置社交网络的研究热点之一。在已有的综述中缺乏数据问题对策的梳理、前沿算法的更新、算法性能对比实验等内容。因此对这一领域的研究进行系统性综述,从数据问题、算法技术和对比实验三个方面进行归纳总结。从POI数据问题角度分析并归纳出数据稀疏、数据依赖和数据隐私三大问题及其对应的解决方法;从算法所用技术角度将现有重要研究分为矩阵分解、编码器、图神经网络、注意力机制、生成模型五类,比较并总结其优劣;从算法性能对比角度出发,选取使用频度最高的召回率和精度作为评价指标,对五个代表性算法进行实验及评价;指出该领域所面临的挑战和未来研究方向。展开更多
城乡结合部边界识别是城乡精细规划与治理的基础工作,对于土地可持续利用、城乡一体化等进程具有推动作用。以往城乡结合部划分存在数据源单一、获取困难、时空分辨率低的不足,基于电子地图的兴趣点(point of interest,POI)和国家极地...城乡结合部边界识别是城乡精细规划与治理的基础工作,对于土地可持续利用、城乡一体化等进程具有推动作用。以往城乡结合部划分存在数据源单一、获取困难、时空分辨率低的不足,基于电子地图的兴趣点(point of interest,POI)和国家极地轨道伙伴关系(national polar-orbiting partnership,NPP)卫星的夜间灯光融合数据,构建NPP&POI综合指数;结合城乡空间结构关系,提出了一种新的城乡结合部空间识别方法。以武汉市为例,采用断裂点分析法识别空间突变点,求得城乡结合部边界,利用土地利用结构信息熵、归一化植被指数(normalized difference vegetation index,NDVI)以及人口密度数据对划定结果进行验证和比较,并对典型区域进行了野外实地校核。结果表明,相较于单独采用POI、夜间灯光和人口密度数据,NPP&POI综合指数考虑了夜间灯光与POI中设施类型、光照强度和分辨率差异,其划分识别出的城乡结合部边界准确度更高、时效性更强;相较于土地利用、景观等数据,NPP&POI综合指数更能表征城乡发展活力,定量识别出城乡潜在中心区与多层结构对于城乡基础设施的配置、产业分工、生态职能划分等研究具有参考意义。NPP&POI综合指数在城乡空间上的二次突变规律证实了城乡结合部作为城市扩张过程中产生的地域实体客观存在,为城乡三元结构理论提供了实证支撑。展开更多
利用兴趣点(point of interest,POI)数据对小尺度经济活动的有效描述功能,以西安市为例,探究轨道交通站域生产性服务业的空间分布特征。在提出站域范围确定方法并整合城市内部生产性服务业业态类型的基础上,通过区位商测度揭示6类业态...利用兴趣点(point of interest,POI)数据对小尺度经济活动的有效描述功能,以西安市为例,探究轨道交通站域生产性服务业的空间分布特征。在提出站域范围确定方法并整合城市内部生产性服务业业态类型的基础上,通过区位商测度揭示6类业态的站域空间分布整体特征及局域特征,借助二阶偏相关分析研判站域物质空间环境对各类业态分布强度的影响,并解译蕴含的空间分布影响机制。结果表明:(1)生产性服务业业态的站域空间分布大都呈现相对全市总体占优的特征,而各类业态的局域空间分布特征又可细分为向心型、离心型和过渡型;(2)在轨道交通站域内,职住空间的多样性促进大部分业态的站域集中分布,开敞空间的开敞度抑制大部分业态的站域集中分布,道路空间的路网密度则仅对部分业态的空间分布产生较弱的正向影响;(3)西安市轨道交通站域生产性服务业空间分布的影响机制有基于强烈实体产业关联的互补性机制、基于空间资源博弈的竞争性机制、基于特定部门非典型需求的有选择支持性机制。展开更多
运用大数据与传统地理信息系统相结合的方式,以山西旅游景区POI(Point of Interest)数据为研究对象,对其进行分类后,研究其总体空间分布格局、分布方向以及具体地市空间分布特征。结果表明:山西旅游景区总体分布格局呈现晋中地区集聚特...运用大数据与传统地理信息系统相结合的方式,以山西旅游景区POI(Point of Interest)数据为研究对象,对其进行分类后,研究其总体空间分布格局、分布方向以及具体地市空间分布特征。结果表明:山西旅游景区总体分布格局呈现晋中地区集聚特征,具体各类旅游景区的集聚形态与程度有所差异。其中,地文景观类旅游景区集聚于晋中、晋东南和晋北东部地区;水域风光类旅游景区以晋中、晋南和晋北东部地区为轴呈条带状分布;生物景观类旅游景区在空间上呈"菱形"状集聚形态;遗址遗迹类旅游景区集聚于晋北和晋东南地区;建筑与设施类旅游景区呈"三角形"状集聚特征;娱乐购物类旅游景区在全省范围内分布较为均匀。旅游景区空间分布方向与山西省区域形状吻合,除娱乐购物类旅游景区分布方向性和向心性不明显之外,其他类别旅游景区均有不同程度的集聚特征;各地市旅游景区分布情况中,水域风光类旅游景区在各市域间分布较为均匀,地文景观类和建筑设施类旅游景区热点区域出现在阳泉市,冷点区域出现在晋城市,但其集聚程度均较低;生物景观类旅游景区热点区域位于长治市,冷点区域位于临汾市和运城市,其集聚程度较高。最后,从自然地理和人文社会两方面对旅游景区空间分布的影响因素进行了定性分析。展开更多
基金supported by the National Natural Science Foundation of China,No.31100711,51377045,31300818the Natural Science Foundation of Hebei Province,No.H2013202176
文摘Here, we administered repeated-pulse transcranial magnetic stimulation to healthy people at the left Guangming (GB37) and a mock point, and calculated the sample entropy of electroencephalo- gram signals using nonlinear dynamics. Additionally, we compared electroencephalogram sample entropy of signals in response to visual stimulation before, during, and after repeated-pulse tran- scranial magnetic stimulation at the Guangming. Results showed that electroencephalogram sample entropy at left (F3) and right (FP2) frontal electrodes were significantly different depending on where the magnetic stimulation was administered. Additionally, compared with the mock point, electroencephalogram sample entropy was higher after stimulating the Guangming point. When visual stimulation at Guangming was given before repeated-pulse transcranial magnetic stimula- tion, significant differences in sample entropy were found at five electrodes (C3, Cz, C4, P3, T8) in parietal cortex, the central gyrus, and the right temporal region compared with when it was given after repeated-pulse transcranial magnetic stimulation, indicating that repeated-pulse transcranial magnetic stimulation at Guangming can affect visual function. Analysis of electroencephalogram revealed that when visual stimulation preceded repeated pulse transcranial magnetic stimulation, sample entropy values were higher at the C3, C4, and P3 electrodes and lower at the Cz and T8 electrodes than visual stimulation followed preceded repeated pulse transcranial magnetic stimula- tion. The findings indicate that repeated-pulse transcranial magnetic stimulation at the Guangming evokes different patterns of electroencephalogram signals than repeated-pulse transcranial mag- netic stimulation at other nearby points on the body surface, and that repeated-pulse transcranial magnetic stimulation at the Guangrning is associated with changes in the complexity of visually evoked electroencephalogram signals in parietal regions, central gyrus, and temporal regions.
文摘In recent years,decision support systems(DSSs)have successfully deployed ontologies in their architecture.The result of such a use is information systems that assist users and organizations in semi-structured decision-making activities.Visitors from throughout Iran travel to different cities and regions every year,and they need help making their choices.Some of these tourists are unable to visit the beautiful areas of the destination city due to a lack of awareness.In this study,we design an ontology-based spatial DSS to find entertainment and tourism centers in Arak,Iran.The objective is to provide users with recommendations appropriate for the location,time,age group,type of activity,and other factors.In this model,the demands and concerns of tourists have been managed by creating a domain Web Ontology Language(OWL)for entertainment centers as a knowledge base in the Protégéenvironment.The developed webbased DSS operates on a client-server architecture using technologies such as Werkzeug and Flask.As a result,it makes it possible to ontology reasoning based on the HermiT engine to choose the right center and conduct a semantic search on classes related to the appropriate point of interest.The main distinction between the proposed methodology and the previous studies on spatial DSS is that criteria are object properties in an ontology.Therefore,decision support relies on real-time reasoning rather than transforming criteria into geospatial layers.The evaluation results confirmed efficient interaction with this system,purposeful information retrieval,and rapid decision-making process.The results also indicated that searching for a POI(point of interest)in the study area using the developed system is at least 30%more successful than a search engine or social media.Moreover,to overcome the cold start problem,the proposed technique might be utilized in conjunction with the POI recommender systems.
文摘长春市是国家新型城镇化综合试点城市,识别长春市中心城区功能,针对当前存在的问题提出对策建议,对城市空间的优化与协调具有重要意义。以兴趣点(Point of Interest,POI)数据及开放街道地图(Open Street Map,OSM)数据为基础,结合核密度分析、实地调查验证等方法,识别长春市中心城区城市功能类型。结果表明:单一功能区中,商业功能区数量最多,居住功能区最少;主导—混合功能区中的商业主导功能区及交通主导功能区形成对商业聚集区与轨道交通系统的重要补充;细分—混合功能区特征显示功能混合程度从市中心向周边逐渐加大。经验证,城市功能识别结果符合长春市实际,由此提出对策建议:未来长春市中心城区应注重多中心发展格局,并加强绿地空间和公共服务设施建设。
文摘兴趣点(point of interest,POI)推荐可以缓解用户选择困难问题并提高位置服务商、商家的收益,是位置社交网络的研究热点之一。在已有的综述中缺乏数据问题对策的梳理、前沿算法的更新、算法性能对比实验等内容。因此对这一领域的研究进行系统性综述,从数据问题、算法技术和对比实验三个方面进行归纳总结。从POI数据问题角度分析并归纳出数据稀疏、数据依赖和数据隐私三大问题及其对应的解决方法;从算法所用技术角度将现有重要研究分为矩阵分解、编码器、图神经网络、注意力机制、生成模型五类,比较并总结其优劣;从算法性能对比角度出发,选取使用频度最高的召回率和精度作为评价指标,对五个代表性算法进行实验及评价;指出该领域所面临的挑战和未来研究方向。
文摘利用兴趣点(point of interest,POI)数据对小尺度经济活动的有效描述功能,以西安市为例,探究轨道交通站域生产性服务业的空间分布特征。在提出站域范围确定方法并整合城市内部生产性服务业业态类型的基础上,通过区位商测度揭示6类业态的站域空间分布整体特征及局域特征,借助二阶偏相关分析研判站域物质空间环境对各类业态分布强度的影响,并解译蕴含的空间分布影响机制。结果表明:(1)生产性服务业业态的站域空间分布大都呈现相对全市总体占优的特征,而各类业态的局域空间分布特征又可细分为向心型、离心型和过渡型;(2)在轨道交通站域内,职住空间的多样性促进大部分业态的站域集中分布,开敞空间的开敞度抑制大部分业态的站域集中分布,道路空间的路网密度则仅对部分业态的空间分布产生较弱的正向影响;(3)西安市轨道交通站域生产性服务业空间分布的影响机制有基于强烈实体产业关联的互补性机制、基于空间资源博弈的竞争性机制、基于特定部门非典型需求的有选择支持性机制。
文摘运用大数据与传统地理信息系统相结合的方式,以山西旅游景区POI(Point of Interest)数据为研究对象,对其进行分类后,研究其总体空间分布格局、分布方向以及具体地市空间分布特征。结果表明:山西旅游景区总体分布格局呈现晋中地区集聚特征,具体各类旅游景区的集聚形态与程度有所差异。其中,地文景观类旅游景区集聚于晋中、晋东南和晋北东部地区;水域风光类旅游景区以晋中、晋南和晋北东部地区为轴呈条带状分布;生物景观类旅游景区在空间上呈"菱形"状集聚形态;遗址遗迹类旅游景区集聚于晋北和晋东南地区;建筑与设施类旅游景区呈"三角形"状集聚特征;娱乐购物类旅游景区在全省范围内分布较为均匀。旅游景区空间分布方向与山西省区域形状吻合,除娱乐购物类旅游景区分布方向性和向心性不明显之外,其他类别旅游景区均有不同程度的集聚特征;各地市旅游景区分布情况中,水域风光类旅游景区在各市域间分布较为均匀,地文景观类和建筑设施类旅游景区热点区域出现在阳泉市,冷点区域出现在晋城市,但其集聚程度均较低;生物景观类旅游景区热点区域位于长治市,冷点区域位于临汾市和运城市,其集聚程度较高。最后,从自然地理和人文社会两方面对旅游景区空间分布的影响因素进行了定性分析。