Internet of Vehicles (IoV) is a new system that enables individual vehicles to connect with nearby vehicles,people, transportation infrastructure, and networks, thereby realizing amore intelligent and efficient transp...Internet of Vehicles (IoV) is a new system that enables individual vehicles to connect with nearby vehicles,people, transportation infrastructure, and networks, thereby realizing amore intelligent and efficient transportationsystem. The movement of vehicles and the three-dimensional (3D) nature of the road network cause the topologicalstructure of IoV to have the high space and time complexity.Network modeling and structure recognition for 3Droads can benefit the description of topological changes for IoV. This paper proposes a 3Dgeneral roadmodel basedon discrete points of roads obtained from GIS. First, the constraints imposed by 3D roads on moving vehicles areanalyzed. Then the effects of road curvature radius (Ra), longitudinal slope (Slo), and length (Len) on speed andacceleration are studied. Finally, a general 3D road network model based on road section features is established.This paper also presents intersection and road section recognition methods based on the structural features ofthe 3D road network model and the road features. Real GIS data from a specific region of Beijing is adopted tocreate the simulation scenario, and the simulation results validate the general 3D road network model and therecognitionmethod. Therefore, thiswork makes contributions to the field of intelligent transportation by providinga comprehensive approach tomodeling the 3Droad network and its topological changes in achieving efficient trafficflowand improved road safety.展开更多
作为建筑行业的发展方向,建筑信息模型(Building Information Modeling,BIM)技术已然成为实现建筑信息化发展目标的关键技术。在数字校园建设过程中,若能够将地理信息系统与建筑信息模型相融合,则可实现校园全场景的三维可视化与建筑设...作为建筑行业的发展方向,建筑信息模型(Building Information Modeling,BIM)技术已然成为实现建筑信息化发展目标的关键技术。在数字校园建设过程中,若能够将地理信息系统与建筑信息模型相融合,则可实现校园全场景的三维可视化与建筑设施精细化管理。从场景搭建、数字校园建模以及BIM与三维地理信息系统(3D Geographic Information System,3D GIS)结合应用角度出发,阐述了大学数字校园系统设计要点,为数字化校园持续发展奠定基础。展开更多
化学事故具有突发性强、环境污染破坏严重、救援难度大等特点,对突发化学事故的影响范围、破坏程度进行快速评估,为事故抢险救援提供决策支持,是应对重特大突发化学事故、降低事故损失的重要手段。本文基于三维地理信息系统(Three-dimen...化学事故具有突发性强、环境污染破坏严重、救援难度大等特点,对突发化学事故的影响范围、破坏程度进行快速评估,为事故抢险救援提供决策支持,是应对重特大突发化学事故、降低事故损失的重要手段。本文基于三维地理信息系统(Three-dimensional Geographic Information System,3D GIS),在充分考虑下垫面影响的前提下,研究了大气污染扩散模型,提出了扩散场快速构建技术及兼顾污染分区的救援力量调度方法,并以此为核心建立了系统总体框架,形成了集扩散模拟、危害分析、救援调度等功能于一体的突发化学事故危害评估与救援辅助决策支持系统,可为突发化学事故危害后果评估与辅助救援决策提供有效的技术支撑。展开更多
为了城市地下管线的可持续发展,要解决传统市政管线管理模式中存在的信息不透明、管理难度大等问题,以实现三维可视化、管线状态监测及视频监控、故障定位等目标。从系统总体架构和系统功能、数据库建设等方面出发,整合应用建筑信息模型...为了城市地下管线的可持续发展,要解决传统市政管线管理模式中存在的信息不透明、管理难度大等问题,以实现三维可视化、管线状态监测及视频监控、故障定位等目标。从系统总体架构和系统功能、数据库建设等方面出发,整合应用建筑信息模型(building information modeling,BIM)技术与三维地理信息系统(three-dimensional geographic information system,3D GIS)技术,提出智慧地下管线系统的建设方案。结合工程实例,应用智慧地下管线系统,分析与评价其应用效果。以期为未来地下管线的巡查、分析、决策提供数据支持,为相关工程提供借鉴。展开更多
Underground pipeline networks constitute a major component of urban infrastructure,and thus,it is imperative to have an efficient mechanism to manage them.This study introduces a secondary development system to effici...Underground pipeline networks constitute a major component of urban infrastructure,and thus,it is imperative to have an efficient mechanism to manage them.This study introduces a secondary development system to efficiently model underground pipeline networks,using the building information modeling(BIM)-based software Revit.The system comprises separate pipe point and tubulation models.Using a Revit application programming interface(API),the spatial position and attribute data of the pipe points are extracted from a pipeline database,and the corresponding tubulation data are extracted from a tubulation database.Using the Family class in Revit API,the cluster in the self-built library of pipe point is inserted into the spatial location and the attribute data is added;in the same way,all pipeline instances in the pipeline system are created.The extension and localization of the model accelerated the modeling speed.The system was then used in a real construction project.The expansion of the model database and rapid modeling made the application of BIM technology in three-dimensional visualization of underground pipeline networks more convenient.Furthermore,it has applications in pipeline engineering construction and management.展开更多
While the use of three-dimensional (3D) geographical information system (GIS) is becoming in rapid development and being used in various fields such as urban and regional planning, disaster management and planning, mo...While the use of three-dimensional (3D) geographical information system (GIS) is becoming in rapid development and being used in various fields such as urban and regional planning, disaster management and planning, mobile navigation and etc., commercial and open source GIS software packages tend to offer 3D-GIS functionalities for their products. On the basis, GIS analysis functions are to provide information with respect to geographical location and by having 3D spatial data as an input, it will give advantages in providing horizontal position information. However, to analyze moving objects (temporal) in 3D seems not an easy task and not fully supported by current GIS platform packages. Previously in two-dimensional (2D) GIS practice, main issue addressed by researchers in managing temporal spatial objects is GIS packages were designed based on hardware and software constraints whereby it should be based on the temporal spatial objects ontology. Nowadays, the trend of managing temporal 3D data is via 3D spatial simulation or animation. This approach will not in assistance for GIS users in conducting spatial queries. Without having a suitable ontology and valid topological data structure for temporal 3D data, it will cause repetitive of temporal data (redundancy) and complications in executing spatial analysis in 3D environment. Therefore this paper focuses on the ontology for managing moving 3D spatial objects (i.e. air pollution, flood). The characteristics of moving objects were reviewed thoroughly by categorizing it based on its different appearances. Moreover, existing methods in managing temporal database were addressed and discussed for its practicalities. Another important aspect in managing temporal 3D objects is the implementation of topological data structures for 3D spatial objects were reviewed. In the last section of this paper it summarized the issues and further ideas towards implementing and managing temporal 3D spatial objects in GIS based on the Geoinformation Ontology (GeO).展开更多
目前盐腔围岩蠕变模拟中计算网格生成多是理想化的,并没有充分利用真实探测数据。针对这些问题,提出了一种新的三维计算模型生成方法。借助HalfEdge数据结构,基于研究区域边界、DEM(digital element model,数字高程模型)和钻井数据,构...目前盐腔围岩蠕变模拟中计算网格生成多是理想化的,并没有充分利用真实探测数据。针对这些问题,提出了一种新的三维计算模型生成方法。借助HalfEdge数据结构,基于研究区域边界、DEM(digital element model,数字高程模型)和钻井数据,构建了研究区域地层三维模型;基于声纳测腔数据构建了盐腔三维模型,并对其进行了拓扑检查与修正;将地层三维模型与盐腔三维模型进行三维空间布尔运算,获取盐腔围岩三维模型;通过对该模型进行三维空间网格离散,得到盐腔围岩四面体网格单元,即数值模拟计算模型。通过该方法构建的三维计算模型,可以为后期盐腔围岩蠕变数值模拟过程提供有效的计算网格,进而可以为盐腔的建造,尤其是安全合理地利用盐腔提供科学依据和技术支持。展开更多
基金the National Natural Science Foundation of China(Nos.62272063,62072056 and 61902041)the Natural Science Foundation of Hunan Province(Nos.2022JJ30617 and 2020JJ2029)+4 种基金Open Research Fund of Key Lab of Broadband Wireless Communication and Sensor Network Technology,Nanjing University of Posts and Telecommunications(No.JZNY202102)the Traffic Science and Technology Project of Hunan Province,China(No.202042)Hunan Provincial Key Research and Development Program(No.2022GK2019)this work was funded by the Researchers Supporting Project Number(RSPD2023R681)King Saud University,Riyadh,Saudi Arabia.
文摘Internet of Vehicles (IoV) is a new system that enables individual vehicles to connect with nearby vehicles,people, transportation infrastructure, and networks, thereby realizing amore intelligent and efficient transportationsystem. The movement of vehicles and the three-dimensional (3D) nature of the road network cause the topologicalstructure of IoV to have the high space and time complexity.Network modeling and structure recognition for 3Droads can benefit the description of topological changes for IoV. This paper proposes a 3Dgeneral roadmodel basedon discrete points of roads obtained from GIS. First, the constraints imposed by 3D roads on moving vehicles areanalyzed. Then the effects of road curvature radius (Ra), longitudinal slope (Slo), and length (Len) on speed andacceleration are studied. Finally, a general 3D road network model based on road section features is established.This paper also presents intersection and road section recognition methods based on the structural features ofthe 3D road network model and the road features. Real GIS data from a specific region of Beijing is adopted tocreate the simulation scenario, and the simulation results validate the general 3D road network model and therecognitionmethod. Therefore, thiswork makes contributions to the field of intelligent transportation by providinga comprehensive approach tomodeling the 3Droad network and its topological changes in achieving efficient trafficflowand improved road safety.
文摘作为建筑行业的发展方向,建筑信息模型(Building Information Modeling,BIM)技术已然成为实现建筑信息化发展目标的关键技术。在数字校园建设过程中,若能够将地理信息系统与建筑信息模型相融合,则可实现校园全场景的三维可视化与建筑设施精细化管理。从场景搭建、数字校园建模以及BIM与三维地理信息系统(3D Geographic Information System,3D GIS)结合应用角度出发,阐述了大学数字校园系统设计要点,为数字化校园持续发展奠定基础。
文摘化学事故具有突发性强、环境污染破坏严重、救援难度大等特点,对突发化学事故的影响范围、破坏程度进行快速评估,为事故抢险救援提供决策支持,是应对重特大突发化学事故、降低事故损失的重要手段。本文基于三维地理信息系统(Three-dimensional Geographic Information System,3D GIS),在充分考虑下垫面影响的前提下,研究了大气污染扩散模型,提出了扩散场快速构建技术及兼顾污染分区的救援力量调度方法,并以此为核心建立了系统总体框架,形成了集扩散模拟、危害分析、救援调度等功能于一体的突发化学事故危害评估与救援辅助决策支持系统,可为突发化学事故危害后果评估与辅助救援决策提供有效的技术支撑。
文摘为了城市地下管线的可持续发展,要解决传统市政管线管理模式中存在的信息不透明、管理难度大等问题,以实现三维可视化、管线状态监测及视频监控、故障定位等目标。从系统总体架构和系统功能、数据库建设等方面出发,整合应用建筑信息模型(building information modeling,BIM)技术与三维地理信息系统(three-dimensional geographic information system,3D GIS)技术,提出智慧地下管线系统的建设方案。结合工程实例,应用智慧地下管线系统,分析与评价其应用效果。以期为未来地下管线的巡查、分析、决策提供数据支持,为相关工程提供借鉴。
基金supported by a grant(No.14DZ2292800,http://www.greengeo.net/)from“Technology Service Platform of Civil Engineering”of Science and Technology Commission of Shanghai Municipality.
文摘Underground pipeline networks constitute a major component of urban infrastructure,and thus,it is imperative to have an efficient mechanism to manage them.This study introduces a secondary development system to efficiently model underground pipeline networks,using the building information modeling(BIM)-based software Revit.The system comprises separate pipe point and tubulation models.Using a Revit application programming interface(API),the spatial position and attribute data of the pipe points are extracted from a pipeline database,and the corresponding tubulation data are extracted from a tubulation database.Using the Family class in Revit API,the cluster in the self-built library of pipe point is inserted into the spatial location and the attribute data is added;in the same way,all pipeline instances in the pipeline system are created.The extension and localization of the model accelerated the modeling speed.The system was then used in a real construction project.The expansion of the model database and rapid modeling made the application of BIM technology in three-dimensional visualization of underground pipeline networks more convenient.Furthermore,it has applications in pipeline engineering construction and management.
文摘While the use of three-dimensional (3D) geographical information system (GIS) is becoming in rapid development and being used in various fields such as urban and regional planning, disaster management and planning, mobile navigation and etc., commercial and open source GIS software packages tend to offer 3D-GIS functionalities for their products. On the basis, GIS analysis functions are to provide information with respect to geographical location and by having 3D spatial data as an input, it will give advantages in providing horizontal position information. However, to analyze moving objects (temporal) in 3D seems not an easy task and not fully supported by current GIS platform packages. Previously in two-dimensional (2D) GIS practice, main issue addressed by researchers in managing temporal spatial objects is GIS packages were designed based on hardware and software constraints whereby it should be based on the temporal spatial objects ontology. Nowadays, the trend of managing temporal 3D data is via 3D spatial simulation or animation. This approach will not in assistance for GIS users in conducting spatial queries. Without having a suitable ontology and valid topological data structure for temporal 3D data, it will cause repetitive of temporal data (redundancy) and complications in executing spatial analysis in 3D environment. Therefore this paper focuses on the ontology for managing moving 3D spatial objects (i.e. air pollution, flood). The characteristics of moving objects were reviewed thoroughly by categorizing it based on its different appearances. Moreover, existing methods in managing temporal database were addressed and discussed for its practicalities. Another important aspect in managing temporal 3D objects is the implementation of topological data structures for 3D spatial objects were reviewed. In the last section of this paper it summarized the issues and further ideas towards implementing and managing temporal 3D spatial objects in GIS based on the Geoinformation Ontology (GeO).
文摘目前盐腔围岩蠕变模拟中计算网格生成多是理想化的,并没有充分利用真实探测数据。针对这些问题,提出了一种新的三维计算模型生成方法。借助HalfEdge数据结构,基于研究区域边界、DEM(digital element model,数字高程模型)和钻井数据,构建了研究区域地层三维模型;基于声纳测腔数据构建了盐腔三维模型,并对其进行了拓扑检查与修正;将地层三维模型与盐腔三维模型进行三维空间布尔运算,获取盐腔围岩三维模型;通过对该模型进行三维空间网格离散,得到盐腔围岩四面体网格单元,即数值模拟计算模型。通过该方法构建的三维计算模型,可以为后期盐腔围岩蠕变数值模拟过程提供有效的计算网格,进而可以为盐腔的建造,尤其是安全合理地利用盐腔提供科学依据和技术支持。
