Научная статья на тему 'New perspectives and challenges of 3D GIS. From automatic building generation to virtual cities, will the Nd GIS be able to represent the user space?'

New perspectives and challenges of 3D GIS. From automatic building generation to virtual cities, will the Nd GIS be able to represent the user space? Текст научной статьи по специальности «Строительство и архитектура»

CC BY
205
57
i Надоели баннеры? Вы всегда можете отключить рекламу.
Ключевые слова
GIS / AEC / CAD / DB / 3D SDI / CITYGML / SPATIAL ONTOLOGY / 3D URBAN MODEL / 3D CITY MODEL / BUILDING / EXCHANGE FORMATS / VIRTUAL CITIES / MAPPING / ARCHITECTURE / GEODESY / HDS / LIDAR / PHOTOGRAMMETRIC SURVEY / AIRBORNE SENSORS / LOCATION BASED SYSTEMS / GNSS / CADASTRE / CLOUD COMPUTING / RFID / UBIQUITOUS LIFE / INTERNET / WI-FI

Аннотация научной статьи по строительству и архитектуре, автор научной работы — Van Cranenbroeck Joël, Lazerko Maria

The questions the authors would like to address in that paper are about the perspectives and challenge that 3D and even 4D GIS are confronted to represent and manage the user space. In our today and future society there is a growing interest and effective need of geospatial information to manage the space and the social life of people, to provide strategic data's to city planners and governmental agencies and also to address the disaster situations like the recent earthquakes in Haiti and Chile. On the other side, the users of such information systems are also willing to interface with their spaces and even to cross over those geospatial data's with their social networks. With the long term experience the professionals have acquired in the formalism, the data structure and the semantic associated with the 2D GIS it would have been straight forwarded to extend the dimensions to the third and even the fourth one as time is an intimate component of the geospatial data. For those who doubt about that the authors would simply refer to the cadastral information that are updated at least on a yearly basis and allow the administrators to setup the genealogy of the rights associated of a given parcel. But it is definitively not the case. Some attempt has been made to upgrade the 2D GIS up to 2.5D GIS where the height would have been considered as an attribute of some objects like the buildings to derive a 3D representation of some limited spaces like cities and industrial areas. The challenges posed by the 3D are of many natures and the fact that today the acquisition technologies (like HDS, LIDAR, Airborne sensors …) allow easily to capture massively the data in 3D is one of the paradoxes. In their conclusions, the authors will suggest a change of paradigm that would address those issues by considering that the geospatial data's must be accessible from the users and from their spaces. After all, the technology is now evolving to Cloud computing that utilizes software as a service (SaaS), such as Web 2.0 and other technology trends, all of which depend on the Internet for satisfying users' needs.

i Надоели баннеры? Вы всегда можете отключить рекламу.
iНе можете найти то, что вам нужно? Попробуйте сервис подбора литературы.
i Надоели баннеры? Вы всегда можете отключить рекламу.

Текст научной работы на тему «New perspectives and challenges of 3D GIS. From automatic building generation to virtual cities, will the Nd GIS be able to represent the user space?»

УДК 528.41.001:528.7

Джоел ван Кроненброк

Leica Geosystems AG, Швейцария

М.М. Лазерко

СГГА, Новосибирск

НОВЫЕ ПЕРСПЕКТИВЫ И ПРОБЛЕМЫ 3D ГИС. ОТ АВТОМАТИЧЕСКОГО ПОСТРОЕНИЯ ЗДАНИЯ ДО ВИРТУАЛЬНЫХ ГОРОДОВ. СПОСОБНА ЛИ N-ПРОСТРАНСТВЕННАЯ ГИС ПРЕДСТАВЛЯТЬ ПРОСТРАНСТВО ПОЛЬЗОВАТЕЛЯ?

Joёl van Cranenbroeck

Leica Geosystems AG, Switzerland

E-mail: [email protected]

Maria Lazerko

Siberian State Academy of Geodesy

Russian Federation

E-mail: [email protected]

NEW PERSPECTIVES AND CHALLENGES OF 3D GIS. FROM AUTOMATIC BUILDING GENERATION TO VIRTUAL CITIES, WILL THE ND GIS BE ABLE TO REPRESENT THE USER SPACE?

Key words: GIS, AEC, CAD, DB, 3D SDI, CityGML, spatial ontology, 3D urban model, 3D city model, Building, Exchange formats, Virtual Cities, Mapping, Architecture, Geodesy, HDS, LIDAR, Photogrammetric survey, Airborne sensors, Location Based Systems, GNSS, Cadastre, Cloud computing, RFID, Ubiquitous life, Internet, Wi-Fi.

SUMMARY

The questions the authors would like to address in that paper are about the perspectives and challenge that 3D and even 4D GIS are confronted to represent and manage the user space.

In our today and future society there is a growing interest and effective need of geospatial information to manage the space and the social life of people, to provide strategic data’s to city planners and governmental agencies and also to address the disaster situations like the recent earthquakes in Haiti and Chile. On the other side, the users of such information systems are also willing to interface with their spaces and even to cross over those geospatial data’s with their social networks.

With the long term experience the professionals have acquired in the formalism, the data structure and the semantic associated with the 2D GIS it would have been straight forwarded to extend the dimensions to the third and even the fourth one as “time” is an intimate component of the geospatial data. For those who doubt about that the authors would simply refer to the cadastral information that are updated at least on a yearly basis and allow the administrators to setup the genealogy of the rights associated of a given parcel.

But it is definitively not the case. Some attempt has been made to upgrade the 2D GIS up to 2.5D GIS where the height would have been considered as an attribute

of some objects like the buildings to derive a 3D representation of some limited spaces like cities and industrial areas.

The challenges posed by the 3D are of many natures and the fact that today the acquisition technologies (like HDS, LIDAR, Airborne sensors ...) allow easily to capture massively the data in 3D is one of the paradoxes.

In their conclusions, the authors will suggest a change of paradigm that would address those issues by considering that the geospatial data’s must be accessibl e from the users and from their spaces. After all, the technology is now evolving to Cloud computing that utilizes software as a service (SaaS), such as Web 2.0 and other technology trends, all of which depend on the Internet for satisfying users' needs.

THE EXPECTATION

Dohyung Kim and Ilir Bejleri already quoted that many urban planning agencies involve the public in the development review process. In this process, the new development proposals are typically presented as a collection of reports, GIS maps,

2-dimensional plans, perspective drawings and photographs.

Frequently, participating citizens face difficulties in fully understanding the proposals due to lack of training in interpreting 2D plans and maps and inability to link all the pieces of information together. This can negatively affect the development approval, discourage future public involvement and may diminish the role of public participation in decision making.

The communication of information to the public can be facilitated by the use of

3-dimensional information, particularly for urban design projects. The 3D digital models, rendered in high realistic details can deliver clear representations of the information and can be successfully used to analyze the proposed developments in the context of the surrounding structures and for comparison of proposed design alternatives.

Moreover, the combination of 3D models with 2D GIS thematic data such as demographics, zoning and property information, provide the comprehensive information required for the understanding and analysis of the complex relationships in city planning.

Recent developments in GIS data structures with a focus in relational databases have created opportunities for a better integration of traditional 2D thematic GIS information with 3D urban models.

Also in our local cities and global economies today, Doug Eberhard in “A Model Vision of the Future” continues to see increased demand and democratization for richer information and communication moving from analogue to digital, 2D to 3D, to 4D and beyond.

So how will we envision and engage CAD, BIM, Geospatial, Analysis, Simulation, Visualization, Web Services and Collaboration tools in the future? How can we work in a more informed, integrated and visual way, while maintaining the security and integrity of our designs, our data and our decisions? How will owners, agencies, businesses and the public interface with this process and information as it becomes more valuable and more available.or not? How will the people, the

policies, the projects and the tools come together to help us better plan, design, construct and maintain a more sustainable world today and in the future?

WHY A 3D GIS SYSTEM IS MUCH MORE COMPLEXE?

To further understand the challenge of increasing the dimension of 2D GIS, we would like first to refer to the tasks or the functions of a GIS (Raper and Maguire, 1992) are: (1) Capture, (2) Structuring, (3) Manipulation, (4) Analysis and (5) Presentation, and can be summarised as follows:

- Capture is inputting spatial data to the system. Many different techniques and devices are available for both geometric and attribute data. The devices in frequent use for collecting spatial data can be classified as manual, semiautomatic or automatic and the output either vector or raster format.

- Structuring is a crucial stage in creating a spatial database using a GIS. This is because it determines the range of functions, which can be used for manipulation and analysis. Different system may have different structuring capabilities (simple or complex topology, relational or object-oriented).

- Manipulation, among important manipulation operations are generalisation and transformation. Generalisation is applied for reducing data complexity or to make the data presentation more legible. Transformation includes coordinate transformation to a specified map projection and scaling, etc.

- Analysis is the core of a GIS system. It involves metric, topological and/or order operations on geometric and attribute data. Primarily, analysis in GIS concerns operations on more than one set of data, which generates new spatial information of the data. Terrain analysis (e.g. inter-visibility), geometric computations (volume, area, etc), overlay, buffering, zoning, sorting are among typical analysis functions in GIS.

- Presentation is a final task in GIS. That is to present all the generated information or results such as in the form of maps, graphs, tables, reports, etc.

Ideally, a 3D GIS should have the same functions as 2D GIS and should be able to model, represent, manage, manipulate, analyse and support decisions based upon information associated with three-dimensional phenomena (Worboys, 1995).

The definition of 3D GIS is very much the same as for 2D system. In 2D GIS systems are common, widely used and able to handle most of the GIS tasks efficiently. The same kind of system may not be able to handle 3D data if more advanced 3D applications are demanded (Raper and Kelk, 1991; Rongxing Li, 1994) - such as representing the full length, width and nature of a borehole. 3D GIS system is not just a simple extension by another dimension (i.e. the 3rd dimension) on to 2D GIS. To add this third dimension into existing 2D GIS needs a thorough investigation of many aspects of GIS including a different concept of modelling, representations and aspects of data structuring.

Existing GIS packages are widely used and understood for handling, storing, manipulating and analysing 2D spatial data. Their capability and performance for 2D and for 2.5D data (that is also DTM) is generally accepted by the GIS community. However a GIS package, which can handle and manipulate 2D data and DTM, cannot

be considered as 3D GIS system because DTM data is not real 3D spatial data. The third dimension of the DTM data only provides (often after interpolation) a surface attribute to features whose coordinates consist only of planimetric data or x, y coordinates. GIS software handling real 3D spatial data is rarely found. Although the problem has been addressed by several researchers such as Raper and Kelk (1991), Cambray (1993), Rongxing Li (1994), and Fritsch (1996), some further aspects particularly spatial data modelling using object-oriented techniques need to be investigated.

Further, works of Pilouk(1996), Abdul-Rahman(2000), and Zlatanova(2000) have investigated the problems and proposed some solutions to the problems. Pilouk’s and Abdul-Rahman’s works were focussed on suitable data structures for the system whereas Zlatanova’s work looked on the use of Web and 3D city buildings.

The developments of 3D GIS is however driven also by the new application and Raper and Kelk (1991), Rongxing Li (1994), Forstner (1995), and Bonham-Carter (1996), Pilouk(1996), Abdul-Rahman(2000) present some of the three dimensional application areas in

GIS, including:

- Ecological studies

- 3D urban mapping

- Environmental monitoring

- Landscape planning

- Geological analysis

- Architecture

- Civil engineering

- Automatic vehicle navigation

- Mining exploration

- Archaeology

- Hydrographic surveying

- Marine biology

The above applications may produce much more useful information if they were handled in a 3D spatial system, but it appears that 3D spatial objects on the surface and subsurface demand more complex solutions (e.g. in terms of modelling, analysis, and visualization) than the existing systems can offer.

The difficulties in realising 3D GIS or 3D geo-spatial systems result mainly from:

- Conceptual model: although there are several data structures available for the 2.5D and 3D data, each of them has its own strong and weak points in representing spatial objects. Spatial data can be modelled in different ways. The conceptual 3D model integrates information about semantics, 3D geometry and 3D spatial relationships (3D topology). The conceptual model provides the methods for describing real-world objects and spatial relationships between them. The design of a conceptual model is a subject of intensive investigations and several 3D models have

already been reported (see Brisson 1990, Molenaar 1992, Cambray 1993, Pilouk 1996, Pigot 1995, Zlatanova 2000, Abdul-Rahman 2000, Pfund 2001).

- Data collection: Modelling in 3D drastically increases the cost of data acquisition, as compared with 2D. Despite the progress in automatic object detection and 3D reconstruction (see Gulch et al 1999, Lang and Forstner 1996), the manual work is still predominant. Methods for constructing the model combining data from various sources, automatic techniques for data acquisition (geometry and images for texturing), rules and algorithms for ensuring consistency of data, algorithms for the automatic building of 3D topology, etc., are the topics still widely discussed in the literature.

- Spatial analysis: Whilst thematic analysis and 2D spatial analysis are well studied, research on 3D spatial analysis is still at an intensive stage. Spatial relationships are the fundament of a large group of operations to be performed in GIS, e.g. inclusion, adjacency, equality, direction, intersection, connectivity, and their appropriate description and maintenance is inevitable. Similar to 2D variants, 3D GIS should be capable to perform metric (distance, length, area, volume, etc), logic (intersection, union and difference), generalisation, buffering, network (shortest way) and merging operations. Except metric operations, most of them require knowledge about spatial relationships.

- Visualisation, navigation and user interface: Advances in the area of computer graphics have made visual media a major ingredient of the current interface and it is likely that graphics will play a dominant role in the communication and interaction with computers in the future. 3D visualisation within 3D GIS requires a number of specific issues to be investigated, e.g. appropriate means to visualise 3D spatial analysis result, tools to effortlessly explore and navigate through large models in real time, and texture the geometry. Observations on the demand for 3D City models (see Gruber et al 1995) show user preferences for photo-true texturing, due to improved model performance in terms of detail and orientation. Trading photo-true texture raises new topics for research, i.e. collection (methods, automation), storage (original images vs. separate pieces) and mapping onto the "geometry". Specific functions of objects modelled in VR systems, and referred to as behaviours; gain an increased popularity as tools for walking through the model, exploring particular phenomena and improving the cognitive perception.

- Internet access: Remote access to 3D spatial information is one of the newest research topics. The Web has already shown a great potential in improving accessibility to 2D spatial information (raster or vector maps) hosted in different computer systems over the Internet. New Web standard (VRML, DML) have created the ability to distribute and navigate in 3D virtual worlds. The research on spatial query and 3D visualisation over the Web has resulted in a few prototype systems (see Coors et al 1998, Lindenbeck et al 1998). The design criteria, however, are visualisation- rather than spatial analysis-oriented.

Research works attempt to address these major issues by investigating the possible uses of several data structures (including some 2D structures), the construction of these data structures, the utilisation of these structures in spatial

modelling, the topological relationships of the 2D, 2.5D, and 3D spatial objects, the development of a database from the spatial data and the implementation of them in the form of a software which can be seen as component of 3D GIS.

THE CASE STUDY OF 3D BUILDING MODELS

The rapid development of multi-sensor and multimedia technologies has made it possible to construct and visualise detailed 3D city models. 3D city models are typically rendered as central perspectives with rich depth cues and a self-explaining character. They offer an intuitive organisation of spatial objects that replicates or reflects the real world, thus utilising the viewer’s natural perception and memory of space as well as spatial relationships (Mallot et al., 2002; Germanchis and Cartwright, 2003).

Indeed 3D city models have been increasingly applied as communication languages and working tools in a growing number of fields such as architecture, construction, archaeological reconstruction, urban planning, tourism, civil engineering, mobile telecommunication, energy supply, navigation, facility management, disaster simulation, spatial cognition and computer game industry.

Although these application fields share the common demand for 3D information, their special requirements considerably differ with regard to precision, actuality, spatial coverage and interoperability.

In other words, what is needed is not one single solution, but rather a number of 3D city models, which can be (1) different resolutions of a city model, (2) different updates of a city model, or (3) interoperable models of different cities spread over a large region. While case (2) and (3) deal with the research issues of spatial-temporal data acquisition and modelling, case (1) focuses on the study of 3D objects in the scale space.

The scale space of 3D buildings is essentially a linear continuum, along which an arbitrary number of milestones can be said to exist referred to as Levels of Detail (LoD). Each LoD corresponds to a certain degree of generalisation. Unlike the 2D topographic maps that have standard official scale series, there are no generally agreed LoDs for 3D buildings.

At its finest Level of Detail (LoD), a building object can be typically described by its external components, roof surface, roof element, external wall surface, wall element, and internal components, floor surface, internal wall, shared wall surface, ground surface and ceiling surface.

Typically associated with its cadastral footprint, a building hull can be assigned a number of general attributes describing the various qualities of the building. Each storey level can be further attributed for example by information about the occupancy. Finally, every internal or external component can be integrated with application-specific attributes such as incident solar energy, temperature or building construction material.

3D building data can be acquired using a variety of terrestrial and non terrestrial techniques.

Among others, aerial photogrammetry, aerial laser scanning, terrestrial measurement, close range photogrammetry, terrestrial laser scanning and official cadastral information have been widely applied.

- Aerial photogrammetry is able to economically capture the roof landscape and ground texture of a large built-up area. The limited resolution of aerial images, however, does not allow the detection of small roof elements. Neither are fa?ade structures acquirable as they are mostly invisible from the air.

- Aerial laser scanning based on LIDAR (LIght Detection And Ranging) technology can be used for direct acquisition of 3D building surfaces. LIDAR scanning can take place day or night, as long as clear flying conditions are present. The cost of laser scanning is usually more expensive than photogrammetric methods, but the directly available 3D surface characterised by a point cloud allows for straightforward data processing.

- Terrestrial measurement is a complementary method for the acquisition of fine details, especially the individual structure points that cannot be observed from the air. The high precision of this method requires laborious field work since terrestrial details are usually selected and measured on site.

- Close range photogrammetry is an economic method for the geometric documentation of complex buildings and texture registration of fa?ades. The result of stereophotogrammetric analysis is usually a precise 3D line drawing composed of the visually characteristic edges and points on building surfaces. Areas between the edges, however, can hardly be interpreted in fine detail.

- Terrestrial laser scanning or ground-based LIDAR technology is used to capture 3D models of complex and irregular buildings. It is relatively expensive and requires large storage capacity since the footprint contains many measure points that do not belong to the building structure. The 3D scanning does not reach as high a precision on structural edges of buildings as close range photogrammetry or terrestrial but its surface-based working principle allows a precise interpretation of the surface areas between characteristic edges.

- The geometric and semantic attributes of buildings documented in cadastral databases and maps provide rich sources for the derivation of building models of different LoDs. Information such as ground plan, the number of storeys and the hypothetical assumptions about the average storey height can easily lead to a block model. Further information such as ridge and eave lines and their terrestrially measured heights can extend the block model to include roof forms. An important advantage of seamlessly available cadastral data is that individual building models from different cities can be easily sewed together to form a value-added 3D model covering a large region.

All these existing methods can be combined to construct high-fidelity and photorealistic 3D building models.

Although methods for the acquisition of 3D building geometries has been constantly improving with regard to precision, reliability, degree of automation and processing speed, a fully automated procedure for constructing high fidelity 3D building models is not yet in sight.

The existing approaches, even in combination, are too time intensive and expensive for 3D data acquisition and updating. The lack of access to actual and extensive building models in various LoDs has hindered the integration of thematic information of different granularities. Moreover, the existing different LoDs of 3D buildings within a limited spatial scope are often captured separately, using different methods. The missing linkages result in a high maintenance cost and difficulties for the user in conducting multi-scale spatial analysis.

Adding the third dimension has dramatically increased the complexity of a building model in both a geometric and a semantic sense. While a large-scale 2D building is represented by its cadastral ground plan, the appearance of a 3D building is characterised by a lot more surface elements. Consequently, it can take many possible forms. The meaning of a 2D building is usually expressed by a number of semantic attributes attached to its ground plan. In 3D space, however, every surface element of a building can be described by special semantic attributes in addition to its more general attributes.

Bearing in mind the complexity of a 3D building model, cartographers are confronted with the challenging task of deriving constraints for model generalisation from the interdependencies among building parts, neighbourhood relationships among individual buildings, and spatial structures of settlement blocks.

So far the knowledge and conceptual models necessary to support these structures are still largely missing and still fields of research.

TOWARD THE CREATION OF A GENERIC META 3D URBAN SPATIAL INFORMATION META-MODEL

The need of 3D urban spatial data infrastructure (3D SDI) is now almost commonly accepted. However, their implementation suffers from a lack of standardisation. This is usually due to an underestimation of the initial conceptual step, where modelling options should be clearly stated.

Roland Billen, Franfois Laplanche, Siyka Zlatanova and Ludvig Emgard (2008) used an ontological approach inspired by their experience in spatial data acquisition techniques.

The starting point of that ontology is to consider that the universe is composed by free space and occupied space where their interface is the only measurable feature. On that basis, a generic 3D urban spatial information meta-model is elaborated and compared to the CityGML standard through the study of the building object. Except from some Level of Detail (LoD) issues, both models are compatible.

TO RESTORE THE SPACE TO THE PEOPLE - A CHANGE OF PARADIGM

To achieve the integration a 3D geospatial data infrastructure has to be built in order to connect the existing information islands created by traditional disciplines such as architecture, civil engineering and GIS but with different focus.

Usually GIS is used to represent the current status of a whome city for administrative purposes while in contrast, planning and construction professionals focus on the future shape and status of a relatively small part city or just individuals buildings in very high detail.

Due to the historic development of domain specific applications, systems and formats, the different data sources are not interoperable per se. Dollner and Hargerdorn (2007) have shown an integration of these data on visualization level using a service-based 3D viewer based on the OGC Web Service initiative 4 (OWS-4).

However, new challenge such as disaster management, sustainable development, and energy-efficiency require do not only require an integration on visualization level, but an integration and convergence on data model level to enable intelligent data processing on city scale level.

iНе можете найти то, что вам нужно? Попробуйте сервис подбора литературы.

When those information systems will be available the question of the availability to the users of the users will still most probably stay as a serious issue.

The strategic goal for 2010 set for Europe is “to become the most competitive and dynamic knowledge-based economy in the world, capable of sustainable economic growth with more and better jobs and greater social cohesion." (Lisbon European Council, 2000)

This new style of society is defined as the „Information Society’, in which low-cost information and Information Communication Technologies (ICTs) are in general use. E-Government has been defined as one of the most important goals in achieving the Information Society (European Commission, 2005a), which intends to provide the public with the services of government.

As one of the most important section of e-Government, e-Planning is about using ICTs to facilitate the urban planning process, with the support of government policy (Communities and Local Government, 2004). The aim of e-Planning is to enable easy access to information, guidance and services that support and assist planning applicants, and streamlined means of sharing and exchanging information among key players. As traditional planning process, socio-economic, environmental and natural resource issues need to be considered in e-Planning to ensure urban sustainable development and to enhance the quality of human life.

The public is the most essential stakeholder in urban planning and should be considered carefully in the urban planning process, since they consist of the most unpowered group (Vasconcelos et al., 2000). It is no doubt that efficient public participation can help government officials and other professionals to create better planning alternatives. In the context of e-Government and e-Planning, one of main aims of the Information Society is to enhance the dialogue between the public and authorities, based on the sharing of information and the genuine participation of social groups at various levels (European Commission, 2004).

In order to achieve this aim, an important concept, the „e-Inclusion’, is introduced by the umbrella strategy of i2010 launched by the European Commission, which “ensures all people, especially the poor, the uneducated and the unskilled ones have access to this new society and benefit equally from ICTs for network strengthening, information sharing, creating knowledge resources and developing skills necessary for life/work in the new digital environment” European Commission, 2005b).

The authors suggest a dramatic change of paradigm in the way the spatial information would be capture and distribute to restore the space to the people.

TECHNOLOGY CONVERGENCE ASKS FOR A CHANGE OF PARADIGM

From the difficulties to represent the user’s space using geospatial infrastructure to one of the final goal to make that information available to the street people the authors believe that a change of paradigm is the future step.

The digital cities issue from the digital earth concept (Vice President US Al Gore, January 31, 1998 in California Science Centre, Los Angeles - California) highlighted the goal:

“We have an unparalleled opportunity to turn a flood of raw data into understandable information about our society and out planet. This data will include not only high-resolution satellite imagery of the planet, digital maps, and economic, social, and demographic information. If we are successful, it will have broad societal and commercial benefits in areas such as education, decision-making for a sustainable future, land-use planning, agricultural, and crisis management. The Digital Earth project could allow us to respond to manmade or natural disasters - or to collaborate on the long-term environmental challenges we face.

A Digital Earth could provide a mechanism for users to navigate and search for geospatial information - and for producers to publish it. The Digital Earth would be composed of both the "user interface" - a browsable, 3D version of the planet available at various levels of resolution, a rapidly growing universe of networked geospatial information, and the mechanisms for integrating and displaying information from multiple sources.

A comparison with the World Wide Web is constructive. [In fact, it might build on several key Web and Internet standards.] Like the Web, the Digital Earth would organically evolve over time, as technology improves and the information available expands. Rather than being maintained by a single organization, it would be composed of both publicly available information and commercial products and services from thousands of different organizations. Just as interoperability was the key for the Web, the ability to discover and display data contained in different formats would be essential.”

What has changed from January 1998 is that China for instance took share in that project and now it’s hundreds of large cities that are organizing themselves digitally and with the emergence of powerful communication infrastructure and broadband wireless Internet, South Korea has also launched their “Ubiquitous” government programs where the RFID (Radio Frequency IDentification) technology will play an important role.

RFID (radio frequency identification) is a technology that incorporates the use of electromagnetic or electrostatic coupling in the radio frequency (RF) portion of the electromagnetic spectrum to uniquely identify an object, animal, or person. RFID is coming into increasing use in industry as an alternative to the bar code. The advantage of RFID is that it does not require direct contact or line-of-sight scanning. An RFID system consists of three components: an antenna and transceiver (often combined into one reader) and a transponder (the tag). The antenna uses radio frequency waves to transmit a signal that activates the transponder. When activated, the tag transmits data back to the antenna. The data is used to notify a

programmable logic controller that an action should occur. The action could be as simple as raising an access gate or as complicated as interfacing with a database to carry out a monetary transaction. RFID is sometimes called dedicated short range communication (DSRC).

DSRC (Dedicated Short Range Communications) is a short to medium range communications service that supports both Public Safety and Private operations in roadside to vehicle and vehicle to vehicle communication environments. DSRC is meant to be a complement to cellular communications by providing very high data transfer rates in circumstances where minimizing latency in the communication link and isolating relatively small communication zones are important.

Positioning technologies have also evolved and if GNSS receivers can provide location to the users where the signals are available, other technologies are under development to provide indoor and outdoor coverage. That is the advent of the LBS (Location Based Services)

A location-based service (LBS) is an information and entertainment service, accessible with mobile devices through the mobile network and utilizing the ability to make use of the geographical position of the mobile device. LBS services can be used in a variety of contexts, such as health, work, personal life, etc. LBS services include services to identify a location of a person or object, such as discovering the nearest banking cash machine or the whereabouts of a friend or employee. LBS services include parcel tracking and vehicle tracking services. LBS can include mobile commerce when taking the form of coupons or advertising directed at customers based on their current location. They include personalized weather services and even location-based games. They are an example of telecommunication convergence.

And the last but not least information step is today the large emergence of social networks.

A social network service focuses on building and reflecting of social networks or social relations among people, e.g., who share interests and/or activities. A social network service essentially consists of a representation of each user (often a profile), his/her social links, and a variety of additional services. Most social network services are web based and provide means for users to interact over the internet, such as email and instant messaging. Although online community services are sometimes considered as a social network service in a broader sense, social network service usually means an individual-centred service whereas online community services are group-centred. Social networking sites allow users share ideas, activities, events, and interests within their individual networks.

There have been some attempts to standardize these services to avoid the need to duplicate entries of friends and interests (see the FOAF standard and the Open Source Initiative), but this has led to some concerns about privacy.

Although some of the largest social networks were founded on the notion of digitizing real world connections, many other networks as seen in the List of social networking websites focus on categories from books and music to non-profit business to motherhood as ways to provide both services and community to individuals with shared interests.

So technology convergence asks for a change of paradigm in the way the geospatial infrastructure will be not only distributed but also organize.

The authors at that stage suggest that the geospatial objects be “animated” in a way that any of those objects would be able to not only carry their own “story” (attributes) but can also be capable of answering solicitations. The so-called “Animated Geospatial Objects ” will be loaded from the data capture specialists such as surveyors (a new role for them) and from the existing GIS database.

In our vision, anyone would be able to ask his environment about itself and create in mobile device such as we have today (mobile phone with positioning services and RFID reader) the representation needed to navigate and better communicate through his social network.

That is obviously a change of paradigm! All the geospatial industry would be hit by that concept as well as all the telecommunication operators.

This is from the author’s opinion an amazing vision that needs to be further developed knowing that if actually the 3D GIS failed to migrate from the initial 2D GIS it’s essentially because the formal meta-models have not been reviewed. We shouldn’t make the same mistake and the authors believe that this change of paradigm will represent an opportunity to re-align most of our geospatial technologies.

The “Animated Geospatial Objects” will bring a new vision of our world but also a better understanding of our environment and our neighbourhoods. Last not least that concept will be the vehicle for building a better world. That is our wish.

References

[1] C.Coskun AYDIN, Osman DEMIR and Mustafa ATASOY, Third Dimension (3D) in Cadastre and Its Integration with 3D GIS in Turkey. FIG Working Week 2004, Athens, Greece, May 22-27, 2004

[2] Roland BILLEN, Franfois LEPLANCHE, Siyka ZLATANOVA and Ludvig EMGARD, Vers la Creation d’un Meta-Modele Generique de l’Information Spatiale 3D Urbaine. Revue XYZ, n°114 - 1er trimester 2008.

[3] DOHYUNG Kim and Ilir BEJLERI, 3D GIS Database Framework for Facilitating Public Participation in City Planning. URISA Public Participation GIS (PPGIS) Conference, 2004.

[4] Ryan STRYNATKA, Erdas Consultant. Tech Convergence: Integrated 3D GIS, A Reality.

[5] Alias Abdul RAHMAN, Sisi ZLATANOVA and Morakot PILOUK. The 3D GIS Software Development: Global Efforts from Researchers and Vendors.

[6] Liqiu MENG and Andrea FORBERG. 3D Building Generalisation. Chapter 11 of Challenges in the Portrayal of Geographic Information. Elsevier Science Ltd.

[7] V. COORS. On the Convergence of 3D-GIS, CAD and 3D Simulation. Stuttgart University of Applied Science. Research projects on renewable energy management in buildings, “Solar Optimized Passive Buildings”. UAS, 2001-2004.

CONTACTS

Joel van Cranenbroeck

Business Development Manager for Geodetic Monitoring

Leica Geosystems AG, GSR EMEA

Rue du Tienne de Mont, 11

BE-5530 MONT - YVOIR

Belgium, Europa

E-mail: [email protected] Maria Lazerko

Siberian State Academy for Geodesy Novosibirsk, Russia Federation E-mail: [email protected]

© ffwoen ean KponenQpoK, M.M. Ha3epKO, 2010

i Надоели баннеры? Вы всегда можете отключить рекламу.