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1.
This paper discusses the integration of three-dimensional (3D) geographic information systems (GIS) and video surveillance systems using augmented reality (AR) techniques. The motivation for this integration is to overcome problems faced by conventional video surveillance systems. Explicit information concerning which camera currently monitors what area in such systems is missing; therefore, insight into the situation depends heavily on the operator’s training and experience. To ensure the complete coordination and monitoring of a situation in a system with multiple cameras, it is necessary to introduce a single reference system. GIS arises as a natural solution because it not only provides a solid ground truth but also provides semantic information that can be highly important in certain video surveillance applications. To integrate information into a GIS application, that information must be georeferenced. Based on our previous research regarding the addition of georeferencing information to surveillance video, this paper introduces models that can be applied to help integrate video and GIS. With an analogy to Milgram’s continuum between the real world and virtual reality, and analogous to the augmented reality and augmented virtuality in Milgram’s continuum, two models of integration are defined here: GIS-augmented video and video-augmented GIS. Then, we define the architecture of GIS-based video surveillance based on these proposed integration models, and finally, a prototype is implemented. The implemented prototype serves as a basis for analysing possible applications of real-world systems based on the integration of GIS and video.  相似文献   

2.
ABSTRACT

A flood evacuation represents a complex geographic phenomenon that includes comprehensive interactions among humans, the flood and urban environments; thus, the simulation of flood evacuations requires crowd simulation models to be coupled with flood models. This paper studies the human-environment relationship during flooding and promotes a simulation model that combines cellular automata and a multiagent system to simulate crowd evacuations in flood disasters. A case study of Niaodao Island was used to evaluate the performance of flood evacuation experiments, and real-participant experiments based on the virtual reality (VR) environment were employed for bench-mark comparisons. The integrated model can provide a comprehensive solution to assist flood risk analysis.  相似文献   

3.
GIS互操作的实现途径评述   总被引:19,自引:1,他引:18  
文中主要探讨了开放式GIS的规程和关键技术,促进数据、系统和机构的互操作,总结了世界上著名公司最近GIS产品实现互操作的技术途径,给出了国际上有关GIS互操作、开放式GIS研究的最新进展以及近期发展方向。  相似文献   

4.
5.
The improvement of geospatial thinking is essential for success in science, technology, engineering, and mathematics disciplines. Training based on the geovisualization and interpretation of landforms can develop the relief interpretation skill. The research reported here focuses on the study of relief visualization and interpretation, using results from a workshop performed with forty-six university students using different displays of geovisualization in a Spatial Data Infrastructure (SDI) geoportal: LiDAR digital surface model, HillShade digital terrain model, digital elevation model, slope model, high-resolution orthophoto, and topographic map. The results are compared with those of another workshop on the same topic carried out with augmented reality (AR) technology. The relief interpretation skill improvement was measured before and after each of the workshops using the Topographic Map Assessment test. The results with the SDI geoportal showed a significant gain in relief interpretation skill between pretest and posttest scores but less than the gain obtained with AR. No differences were found due to the gender of the participants in either case. Key Words: augmented reality, geospatial thinking, landform interpretation, relief interpretation skill, Spatial Data Infrastructure.  相似文献   

6.
This paper explores the way in which GIS, Virtual Reality (VR) and the Internet are closely integrated through the link of Virtual Reality Modelling Language (VRML) for spatial data visualization, analysis and exploration. Integration takes advantage of each component, and enables the dynamic 3D content to be built, visualized, interacted with and deployed all on the Web. To accomplish this, a hybrid approach that merges the conventional client-side and server-side methods is proposed, which offers the best of both worlds in terms of flexibility and capability, as well as the rational use of computing resources. Based on this approach, a Web-based prototype toolkit is designed and implemented by using an affordable desktop GIS through its macro language together with Java, Common Gateway Interface (CGI) and HTML programming. This toolkit comprises a 3D visualization tool, a 3D analysis tool, and a Java/VRML interface, which are respectively used for the creation of VRML models from 2D maps, surface analysis (e.g. profile creation and visibility analysis), and interaction (e.g. selecting and querying) with the output VRML worlds of 3D visualization and analysis. It is demonstrated that this toolkit provides an integrated environment, facilitating users to gain insights from the interaction with virtual environments that are built from existing GIS databases.  相似文献   

7.
从新宅居生活看网络虚拟旅游的前景和方向   总被引:1,自引:1,他引:0  
刘沛林 《地理科学》2020,40(9):1403-1411
随着信息化技术和网络技术的快速发展,居家服务系统的越来越完善,不愿或不能出门实现旅游目的的人群越来越庞大。对于数量巨大的不愿或不能外出旅游的“宅居”人群来说,通过网络实现虚拟旅游是最理想的方案。网络虚拟旅游在中国起步晚,但近年来发展快,已表现出产品多样化、技术集成化、需求娱乐化、用户大众化、功能休闲化等特点。目前要解决的主要问题集中在:① 3D高清动态仿真效果提质的技术实现问题;② 运用AR等新技术优势解决现场体验感不足的问题;③ 解决景区如何在网络虚拟旅游中受益的问题。未来的网络虚拟旅游方向是:① 在线产品越来越真实化和高清化;② 客源市场越来越大众化和多元化;③ 产品内容越来越多样化和分众化;④ 展示平台越来越普及化和共享化。  相似文献   

8.
虚拟城市是 3维城市地理信息系统的前沿领域 ,该文对在微机上如何建立虚拟城市作了初步探讨 ,把建立虚拟城市的方法分为 3维真实场景建模、海量数据环境下的场景漫游以及确定任意时刻声音文件的调入时机三个部分。重点介绍了控制三维场景漫游、自适应层次细节模型、简单碰撞检测的实现方法 ,并提出了采用泰森模型调用声音文件的新思路。最后给出在VC 开发环境下用OpenGL建立虚拟城市的应用实例。  相似文献   

9.
《The Journal of geography》2012,111(5):307-313
Abstract

Instructors have continually sought new methods and teaching aids to improve lectures and course content. This is especially true today as relevance and innovation become by-words in course evaluations. The recent availability of color space photography provides the instructor with a valuable new method of illustrating geographic phenomena. This photography complements the usual combinations of visual aids in three ways: (1) Scale; (2) Context; and (3) Realism. After textbook diagrams have focused the student's attention on separate geographic features, photographs taken from space place these phenomena in the fuzzy context of reality. By using the two concepts together the student can obtain a better perspective of the interrelationship of geographic factors in the real world.  相似文献   

10.
国外旅游研究领域Web点击流分析研究进展   总被引:1,自引:1,他引:0  
Web点击流数据记录了在线旅游者使用互联网实际发生的电子记录,为旅游研究提供了新机会。该文介绍了Web点击流数据的特性及Web点击流数据分析在旅游研究中的价值,回顾了国外Web点击流分析在旅游研究领域的相关进展,包括旅游网站(目的地网站和酒店网站)访问者行为、旅游者在线信息搜索以及旅游目的地建议系统等,并对其发展前景进行了讨论。  相似文献   

11.
The increased popularity of standards for geospatial interoperability has led to an increasing number of geospatial Web services (GWSs), such as Web Map Services (WMSs), becoming publicly available on the Internet. However, finding the services in a quick and precise fashion is still a challenge. Traditional methods collect the services through centralized registries, where services can be manually registered. But the metadata of the registered services cannot be updated timely. This paper addresses the above challenges by developing an effective crawler to discover and update the services in (1) proposing an accumulated term frequency (ATF)–based conditional probability model for prioritized crawling, (2) utilizing concurrent multi-threading technique, and (3) adopting an automatic mechanism to update the metadata of identified services. Experiments show that the proposed crawler achieves good performance in both crawling efficiency and results' coverage/liveliness. In addition, an interesting finding regarding the distribution pattern of WMSs is discussed. We expect this research to contribute to automatic GWS discovery over the large-scale and dynamic World Wide Web and the promotion of operational interoperable distributed geospatial services.  相似文献   

12.
典型绿洲土地利用/土地覆被变化的可视化模拟初步分析   总被引:18,自引:7,他引:11  
新疆绿洲集中了全疆90%以上的人口和95%以上的社会财富。绿洲土地利用和覆盖变化(LUCC)在新疆生态环境变化中起到主导作用,它直接影响着新疆社会经济的稳定与可持续发展。充分认识绿洲环境变化需要成熟的技术和有效的方法,规划与决策同样需要有效的交流途径和方式。目前,地图、遥感和GIS结合的应用方法,已经非常普遍应用到地理要素的空间分布研究中,并有效地揭示景观要素的空问分布、相互关系和时空模式。由于这些方法表现三维景观时,容易产生空问信息的丢失和理解的困难,且不易再现环境的动态变化。GIS结合虚拟现实技术(VR)可以充分利用两者的优势,可模拟真实景观和再现时空变化过程。本文以三工河绿洲为例,针对新疆典型绿洲的LUCC,对GIS与VR技术结合的方法进行了探索,提出了新的认识典型绿洲LUCC的途径,为有效地认识和研究绿洲环境变化、设计和规划它的未来,提供了动态交互的可视化模拟分析手段。  相似文献   

13.
Abstract

Inquiry-based learning has a long tradition in geography education, and many faculty members are using inquiry to tap the constructivist potential of the World Wide Web. This paper reports on the development of a scoring guide that assesses the degree to which teaching materials support issues-based geographic inquiry. The scoring guide was tested in a content analysis of geographers7 Web-based teaching materials. The results of the preliminary analysis suggest that relatively few geography teaching materials on the Web bear the characteristics of inquiry. Additional research is needed to determine whether teaching materials on the Web are facilitating a shift toward constructivist practice in the discipline.  相似文献   

14.
Abstract

Models can greatly assist the student to understand important aspects of a complex reality. A simple model, based on empirical data about farm size in Tokugawa, Japan, is here introduced and applied to China. The model makes explicit one of the major lessons East Asian civilization has for regions of the world more recently integrated into “civilization”; that is, that the productive capacity of land, and thus its ability to support people, is finite. The model also provides a useful integrative framework for introduction to the physical aspects of the geography of East Asia.  相似文献   

15.
In a Web service‐based distributed environment, individual services must be chained together dynamically to solve a complex real world problem. The Semantic Web Service has shown promise for automatic chaining of Web services. This paper addresses semi‐automatic geospatial service chaining through Semantic Web Services‐based process planning. Process planning includes three phases: process modeling, process model instantiation and workflow execution. Ontologies and Artificial Intelligence (AI) planning methods are employed in process planning to help a user dynamically create an executable workflow for earth science applications. In particular, the approach was implemented in a common data and service environment enabled by interoperable standards from OGC and W3C. A case study of the chaining process for wildfire prediction illustrates the applicability of this approach.  相似文献   

16.
Current data sharing in the Internet environment is supported using metadata at the file level. This approach has three fundamental shortcomings. First, sharing data from different sources with different semantics, data models, and acquisition methods usually requires data conversion and/or integration like data conflation. This can be tedious and error‐prone. Second, data updated from one source cannot be automatically propagated to other related data or applications. Finally, data sharing at the file level makes it difficult to provide feature‐level data for searching, accessing, and exchanging in real time over the Internet. This paper addresses these three issues by proposing a standards‐based framework for sharing geospatial data in the transportation application domain. The proposed framework uses a standard data model—geospatial data model proposed by the Geospatial One‐Stop initiative to harmonize the semantics and data models without the use of data integration methods. It uses Geography Markup Language (GML) for geospatial data coding and feature relationship, which provides a basis to propagate the data update from one source to related other sources and applications, and to search and extract data at the feature level. The framework uses the Web Feature Service (WFS) to search, access and extract data at the feature level from distributed sources. Finally, the Scalable Vector Graphics (SVG) standard was used for data display on the Web browser. Two transportation network datasets are used in the prototype case study to implement the proposed framework. The prototype allows the user to access and extract data at the feature level on the Web from distributed sources without downloading the full data file. It shows that the proposed standards‐based feature‐level data‐sharing system is capable of sharing data without data conflation, accessing, and exchanging data in real time at the feature level. The prototype also shows that changes in one database can be automatically reflected or propagated in another related database without data downloading.  相似文献   

17.

Significant interaction challenges arise in both developing and using interactive map applications. Users encounter problems of information overload in using interactive maps to complete tasks. This is further exacerbated by device limitations and interaction constraints in increasingly popular mobile platforms. Application developers must then address restrictions related to screen size and limited bandwidth in order to effectively display maps on mobile devices. In order to address issues of user information overload and application efficiency in interactive map applications, we have developed a novel approach for delivering personalized vector maps. Ongoing task interactions between users and maps are monitored and captured implicitly in order to infer individual and group preferences related to specific map feature content. Personalized interactive maps that contain spatial feature content tailored specifically to users' individual preferences are then generated. Our approach addresses spatial information overload by providing only the map information necessary and sufficient to suit user interaction preferences, thus simplifying the completion of tasks performed with interactive maps. In turn, tailoring map content to specific user preferences considerably reduces the size of vector data sets necessary to transmit and render maps on mobile devices. We have developed a geographic information system prototype, MAPPER (MAP PERsonalization), that implements our approach. Experimental evaluations show that the use of personalized maps helps users complete their tasks more efficiently and can reduce information overload.  相似文献   

18.
To improve the efficiency of planning and designing silt dam systems, this article employs theories and technologies of collaboration and distributed virtual geographic environments (VGEs) to construct a collaborative virtual geographic environment (CVGE) system. The CVGE system provides geographically distributed users with a shared virtual space and a collaborative platform to implement collaborative planning. Many difficulties have been found in integrating data resources and model procedures for the planning of silt dam systems because of their diversity in heterogeneous environments. Unlike most of the current distributed system applications, the proposed CVGE system not only supports multi-platform and multi-program-language interoperability in the dynamically changing network environment, but also shares programs, data and software in the collaborative environment. Based on creating a shared 3D space by virtual reality technology, agent and grid technologies were tightly coupled to develop the CVGE system. A grid-based multi-agent system service framework was designed to implement this new paradigm for the CVGE system, which efficiently integrates and shares geographically distributed resources as well as having the ability to build modelling procedures on different platforms. At the same time, mobile agent computing services were implemented to reduce the network load, process parallel tasks, enhance communication efficiency and adapt dynamically to the changing network environment. Using Java, JMF (Java Media Framework API), Globus Toolkits (GT) core, Voyager, C++, and the OpenGL development package, a prototype system was developed to support silt dam systems planning in the case study area, the Jiu-Yuan-Gou watershed of the Loess Plateau, China. Compared with the traditional workflow, the CVGE system can reduce the workload by between one third and a half.  相似文献   

19.
《The Journal of geography》2012,111(6):338-342
Abstract

Over the past few years, considerable effort has been expended to improve the methods of teaching introductory courses in geography. For example, techniques such as the “open classroom” and simulation models have been introduced and seem to be successful, if for no other reason than their novelty. A new approach generates interest and induces the student to make a more personal commitment to his geography course and thereby provides a stronger motivation to learn. Of course, this is a primary concern even when the instructor employs standard approaches to classroom teaching.  相似文献   

20.
About one decade has passed since US vice president Al Gore articulated his vision of Digital Earth (DE). Within this decade, a global multi-resolution and three-dimensional (3D) representation of the Earth, which sums up the DE vision, increasingly gained interest in both public and science. Due to the desired high resolution of the available data, highly detailed 3D city models comprise a huge part of DE and they are becoming an essential and useful tool for a range of different applications. In the past as well as at present, 3D models normally come from a range of different sources generated by professionals, such as laser scans or photogrammetry combined with 2D cadaster data. Some models are generated with semi-automated or fully automated approaches, but in most cases manual fine tuning or even manual construction from architectural plans is required. Further beyond outdoor city models, DE additionally envisages the provision of indoor information. That is, the interior structure of public or publically accessible buildings, such as airports or shopping malls, is represented and made available in 3D; however, at the moment, such models are mostly created by hand and essentially based on professional data sources. In contrast to such professional data, which is mainly captured by surveyors or companies, the last few years revealed the phenomenon of crowdsourced geodata, which receives an increasing attractiveness as an alternative data source for many Geographic Information Systems (GIS). Former research already demonstrated the power and richness of such geodata – especially OpenStreetMap (OSM) – and it has also been proved that this non-standardized, crowdsourced geodata can be combined with international standards of the Open Geospatial Consortium (OGC). For example, CityGML Level-of-Detail 1 (LoD1) and LoD2 models have already been created automatically from OSM. The research presented in this article will further continue on the automated generation of CityGML models from OpenStreetMap. Essentially, a method for the creation of highly detailed CityGML LoD4 models with interior structures will be explained. By applying the invented approach on existing OSM data, limitations and restrictions of the IndoorOSM mapping proposal, the available data and the developed approach are revealed and discussed.  相似文献   

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