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3D extraction of buildings is required for many applications such as cadastral, city modelling, infrastructure mapping and urban growth analysis. Moreover, an accurate information about location and dimension of building features provides crucial input for the fire-safety analysis and managing other hazards in an urban environment. Traditionally, building boundaries are delineated based on manual or semi-automated reconstruction from close-range and satellite images. These processes are time-consuming and limited to 2D reconstruction of building objects. The lack of automated methods can be attributed to problems in finding an appropriate information from the data and the complexity in the scene (Elberink 2008).

The cadastral registration system in Malaysia is a parcel based system and it is 2D in nature (Chong 2006; Hassan and Abdul Rahman 2010; Abdul Rahman et al. 2011). This system of cadastral information has served most of the users need for decades. However, in the near future, 2D information may no longer be able to serve the community, especially in more complex situations such as buildings above roads in some large cities and towns. Three dimensional (3D) modelling of cadastral objects such as legal spaces of around buildings, utility networks and other spaces is one of the future aspects for the Malaysian cadastral system. The Malaysian 3D cadastral model could be developed within the framework of the Land Administration Domain Model (LADM) where the generation of the UML model that complies with the concept of LADM for the Malaysian cadastral system can be addressed. The purpose of the LADM is not to replace existing systems, but rather to provide a formal language for describing various sub-systems, so that their similarities and differences can be better understood (ISO 19152 2012).

Indoor navigation is important for various applications such as disaster management, building modeling, safety analysis etc. In the last decade, indoor environment has been a focus of wide research that includes development of indoor data acquisition techniques, 3D data modeling and indoor navigation. In this research, an automated method for 3D modeling of indoor navigation network has been presented. 3D indoor navigation modeling requires a valid 3D model that can be represented as a cell complex: a model without any gap or intersection such that two cells (e.g. room, corridor) perfectly touch each other. This research investigates an automated method for 3D modeling of indoor navigation network using a geometrical model of indoor building environment. In order to reduce time and cost of surveying process, Trimble LaserAce 1000 laser rangefinder was used to acquire indoor building data which led to the acquisition of an inaccurate geometry of building. The connection between surveying benchmarks was established using Delaunay triangulation. Dijkstra algorithm was used to find shortest path in between building floors. The modeling results were evaluated against an accurate geometry of indoor building environment which was acquired using highly-accurate Trimble M3 total station. This research intends to investigate and propose a novel method of topological navigation network modeling with a less accurate geometrical model to overcome the need of required an accurate geometrical model. To control the uncertainty of the calibration and of the reconstruction of the building from the measurements, interval analysis and homotopy continuation will be investigated in the near future Refereed/Peer-reviewed

This paper reports on cartographic enrichments of three dimensional geovirtual environments including the representation of 3D city models. In the recent years 3D city models have become effective and powerful tools that support the simulation and visualization of our real world in a more and more realistic and detailed way. At the same time, there is a growing interest in comprising more information in the virtual living environment in addition to interior and exterior geometric features, roof and facade textures. A lot of information is related to houses, floors, flats, rooms, etc. but also to persons or specific features at certain urban locations. The paper presents the state of the art of cartographic principles in 3D city models, discusses approaches of cartographic enrichments with the aim to bring added values to the visual exploration of 3D geovirtual environments and reveals missing cartographic design rules within this area.

The advantages of three dimensional (3D) city models can be seen in various applications including photogrammetry, urban and regional planning, computer games, etc. They expand the visualization and analysis capabilities of Geographic Information Systems on cities, and they can be developed using web standards. However, these 3D city models consume much more storage compared to two dimensional (2 D) spatial data. They involve extra geometrical and topological information together with semantic data. Without a proper spatial data clustering method and its corresponding spatial data access method, retrieving portions of and especially searching these 3D city models, will not be done optimally. Even though current developments are based on an open data model allotted by the Open Geospatial Consortium (OGC) called CityGML, its XML-based structure makes it challenging to cluster the 3D urban objects. In this research, the authors propose an opponent data constellation technique of space-filling curves (3D Hilbert curves) for 3D city model data representation. Unlike previous methods, that try to project 3D or n-dimensional data down to 2D or 3D using Principal Component Analysis (PCA) or Hilbert mappings, in this research, they extend the Hilbert space-filling curve to one higher dimension for 3D city model data implementations. The query performance was tested for single object, nearest neighbor and range search queries using a CityGML dataset of 1,000 building blocks and the results are presented in this paper. The advantages of implementing space-filling curves in 3D city modeling will improve data retrieval time by means of optimized 3D adjacency, nearest neighbor information and 3D indexing. The Hilbert mapping, which maps a sub-interval of the ([0,1]) interval to the corresponding portion of the d-dimensional Hilbert's curve, preserves the Lebesgue measure and is Lipschitz continuous. Depending on the applications, several alternatives are possible in order to cluster spatial data together in the third dimension compared to its clustering in 2 D.

As cities and urban areas grow and become more complex, the task of managing, updating and displaying three-dimensional urban information can be challenging for city and urban authorities. The emergence of 3D city models has enabled the authorities to work with more reliable and competent data as 3D data (and maps) are proven to be more accurate and relatable in representing real world objects and scenarios. In South East Asia countries such as Malaysia and Singapore, urban development activities are dynamic causing city inventory information to change within short periods of time. The ability to detect and track the changes on building structures located in a city can avoid loss of revenue to the urban authorities as well as improving the efficiency of a city inventory in assisting the decision making process on management level. City inventory management system should be able to store and provide information especially related to the building structure that is needed by the local authority to manage a city efficiently. Current traditional methods utilized by most urban authorities in South East Asia region are inefficient and unable to cope with current complex scenarios in urban areas. This results in some valuable information for building management and information systems being discarded. This research presents a method to boost the efficiency of some aspect in city inventory for local authorities by introducing 3D change detection method on 3D city models. The proposed method is able to detect and analyse changes that occur on 3D buildings using the 3D segmentation approach. A hybrid semantic-geometric 3D segmentation method that deals with segmentation of a 3D building based on its semantic value and surface characteristics, fitted by one of the predefined primitives is presented. The technique is designed to retain existing semantic and geometric information and ultimately enrich it by adding more specialized information. For future work, the proposed method will be implemented as part of the auto-updating module that is able to detect any changes on 3D buildings such as storage and retrieval of semantic information of the changed structure, and automatically update the 3D city models for analysis.

Spatial data modelling information-based systems in current mining operations in Ghana are introduced with particular emphasis on the concepts and the hierarchical structure for three-dimensional (3D) mine. The integration of the various components of a mine is presented, and a queryable 3D mine simulation is also discussed. The conceptual and logical models of 3D tetrahedral model are discussed. This paper discusses the concepts and background knowledge for 3D mine development in general, and then goes further to demonstrate the implementation of the unified spatial data model for mine development. The results showed that a singular spatial data model can be developed to show man-made objects above and below the mine surface.

Cities and urban areas entities such as building structures are becoming more complex as the modern human civilizations continue to evolve. The ability to plan and manage every territory especially the urban areas is very important to every government in the world. Planning and managing cities and urban areas based on printed maps and 2D data are getting insufficient and inefficient to cope with the complexity of the new developments in big cities. The emergence of 3D city models have boosted the efficiency in analysing and managing urban areas as the 3D data are proven to represent the real world object more accurately. It has since been adopted as the new trend in buildings and urban management and planning applications. Nowadays, many countries around the world have been generating virtual 3D representation of their major cities. The growing interest in improving the usability of 3D city models has resulted in the development of various tools for analysis based on the 3D city models. Today, 3D city models are generated for various purposes such as for tourism, location-based services, disaster management and urban planning. Meanwhile, modelling 3D objects are getting easier with the emergence of the user-friendly tools for 3D modelling available in the market. Generating 3D buildings with high accuracy also has become easier with the availability of airborne Lidar and terrestrial laser scanning equipments. The availability and accessibility to this technology makes it more sensible to analyse buildings in urban areas using 3D data as it accurately represent the real world objects. The Open Geospatial Consortium (OGC) has accepted CityGML specifications as one of the international standards for representing and exchanging spatial data, making it easier to visualize, store and manage 3D city models data efficiently. CityGML able to represents the semantics, geometry, topology and appearance of 3D city models in five well-defined Level-of-Details (LoD), namely LoD0 to LoD4. The accuracy and structural complexity of the 3D objects increases with the LoD level where LoD0 is the simplest LoD (2.5D; Digital Terrain Model (DTM) + building or roof print) while LoD4 is the most complex LoD (architectural details with interior structures). Semantic information is one of the main components in CityGML and 3D City Models, and provides important information for any analyses. However, more often than not, the semantic information is not available for the 3D city model due to the unstandardized modelling process. One of the examples is where a building is normally generated as one object (without specific feature layers such as Roof, Ground floor, Level 1, Level 2, Block A, Block B, etc). This research attempts to develop a method to improve the semantic data updating process by segmenting the 3D building into simpler parts which will make it easier for the users to select and update the semantic information. The methodology is implemented for 3D buildings in LoD2 where the buildings are generated without architectural details but with distinct roof structures. This paper also introduces hybrid semantic-geometric 3D segmentation method that deals with hierarchical segmentation of a 3D building based on its semantic value and surface characteristics, fitted by one of the predefined primitives. For future work, the segmentation method will be implemented as part of the change detection module that can detect any changes on the 3D buildings, store and retrieve semantic information of the changed structure, automatically updates the 3D models and visualize the results in a userfriendly graphical user interface (GUI).

One of the most dangerous disaster threatening the high rise and complex buildings of today's world including thousands of occupants inside is fire with no doubt. When we consider high population and the complexity of such buildings it is clear to see that performing a rapid and safe evacuation seems hard and human being does not have good memories in case of such disasters like world trade center 9/11. Therefore, it is very important to design knowledge based realtime interactive evacuation methods instead of classical strategies which lack of flexibility. This paper presents a 3D-GIS implementation which simulates the behaviour of an intelligent indoor pedestrian navigation model proposed for a self -evacuation of a person in case of fire. The model is based on Multilayer Perceptron (MLP) which is one of the most preferred artificial neural network architecture in classification and prediction problems. A sample fire scenario following through predefined instructions has been performed on 3D model of the Corporation Complex in Putrajaya (Malaysia) and the intelligent evacuation process has been realized within a proposed 3D-GIS based simulation.

This paper discusses the method of developing Campus Information System. The system can handle 3D spatial data within desktop and web environment. The method consists of texturing of building facades for 3D building models and modeling 3D Campus Information System. In this paper, some of these steps are carried out; modelling 3D buildings, toggling these models on the terrain and ortho-photo, integration with a geo-database, transferring to the CityServer3D environment by using CityGML format and designing the service, etc. In addition to this, a simple but novel method of texturing of building façades for 3D city modeling that is based on Dynamic Pulse Function (DPF) is used for synthetic and procedural texturing. DPF is very fast compared to other photo realistic texturing methods. Last but not least, it is aimed to present this project on web using web mapping services. This makes 3D analysis easy for decision makers.

Recent synthetic aperture radar (SAR) sensors with a capability of providing data with varying spatial resolutions, polarizations, and incidence angles have attracted greater interest for forest biomass and carbon storage estimation. This study investigates the capability of RADARSAT-2 fine-beam dual-polarization (C-HV and C-HH) data for forest biomass estimation in complex subtropical forest, with different types of processing: 1) raw intensity data (both polarizations separately and as polarization ratio) and 2) texture parameters of both polarizations (separately, jointly, and as polarization ratio). Field data (diameter at breast height and height) were collected from 53 field plots and converted to biomass (dry weight) using a newly developed allometric model. Finally, biomass estimation models were developed between SAR signatures from different processing steps and field plot biomass using stepwise multiple regression. All biomass estimation models using radar intensity data (C-HV, C-HH, and ratio of C-HV and C-HH) proved ineffective, but texture parameters derived from intensity data showed potential. We were able to estimate forest biomass amounts up to 360 t/ha with a goodness of fit of 0.78 (adjusted r2) and an rmse of 28.68 t/ha using the combination of texture parameters of both polarizations (C-HV and C-HH). However, goodness of fit could be improved to 0.91 (adjusted r2) and an rmse of 26.95 t/ha for biomass levels up to 532 t/ha using the ratio of texture parameters of C-HV/C-HH. The result is very encouraging and indicates that the dual-polarization C-band SAR sensor has a potential for the estimation of forest biomass, particularly using the polarization ratio of texture measurements, and biomass estimation can be improved substantially beyond the previously stated saturation level for C-band SAR.

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).

Understanding the behavior of urban air pollution is important en route for sustainable urban development (SUD). Malaysia is on its mission to be a developed country by year 2020 comprehends dealing with air pollution is one of the indicators headed towards it. At present monitoring and managing air pollution in urban areas encompasses sophisticated air quality modeling and data acquisition. However, rapid developments in major cities cause difficulties in acquiring the city geometries. The existing method in acquiring city geometries data via ground or space measurement inspection such as field survey, photogrammetry, laser scanning, remote sensing or using architectural plans appears not to be practical because of its cost and efforts. Moreover, air monitoring stations deployed are intended for regional to global scale model whereby it is not accurate for urban areas with typical resolution of less than 2 km. Furthermore in urban areas, the pollutant dispersion movements are trapped between buildings initiating it to move vertically causing visualization complications which imply the limitations of existing visualization scheme that is based on two-dimensional (2D) framework. Therefore this paper aims is to perform groundwork assessment and discuss on the current scenario in Malaysia in the aspect of current policies towards SUD, air quality monitoring stations, scale model and detail discussion on air pollution dispersion model used called the Operational Street Pollution Model (OSPM). This research proposed the implementation of three-dimensional (3D) spatial city model as a new physical data input for OSPM. The five Level of Details (LOD) of 3D spatial city model shows the scale applicability for the dispersion model implementtation. Subsequently 3D spatial city model data commonly available on the web, by having a unified data model shows the advantages in easy data acquisition, 3D visualization of air pollution dispersion and improves visual analysis of air quality monitoring in urban areas.

Uc boyutlu (3B) kent modellerinin farkli alanlardaki kullanimi gun gectikce onem kazanmaktadir. Gelisen teknoloji ile birlikte gercege cok yakin, semantik veri ile butunlestirilmis ve etkilesimli 3B kent modelleri olusturulabilmektedir. Gorsel ve veritabani tasarimi yapilmis 3B kent modelleri konum analizi, pazarlama, acil durum, afet yonetimi, tesis planlamasi gibi bircok alanda kendine kullanim alani bulmaktadir. Bu makalede 3B kent modeli olusturulurken, amaca yonelik gorsellestirme yapilmasinin onemine deginilmistir. Calismanin amaci, Kampus/Kent Bilgi Sistemleri kapsaminda 3B gorsel modellemeye yonelik ihtiyaclarin ortaya konmasi ve bu modellerin internet ortaminda sunulmasidir. Kampus/Kent bilgi sistemleri karar verme, muhendislik uygulamalari, projelendirme gibi bircok alanda imkan saglamaktir. Calisma kapsaminda dijital fotograflar ile ozel doku kaplama teknikleri kullanilarak Karabuk Universitesi'nin sanal olarak uc boyutlu modeli olusturulmustur. Veri toplama ve isleme kismi 3B bilgi sistemleri olusturulurken en onemli asamalardandir. Bu calismada sanal kampus modelinin uretiminde kampus yerlesim plani, sayisal arazi modeli ve 3B bina modellerinden olusan farkli tipte veriler kullanilmistir.

Scaling factor is one of the most crucial aspect in 2D and 3D models especially in computer graphics, CAD, GIS, and games. Different user or/and application need different scale models during various stages of the use of data, including visualization and interaction. There are some arisen issues on 3D data model especially to meet GIS requirements while minimize the redundancy of the datasets. In GIS modelling, various data structures and data models have been proposed to support variety of applications and dimensionalities, but only a few in scale dimension. Some of them have succeeded in modelling scale such as in Space-Scale Cube (SSC) model. The recently implemented Dual Half-Edge (DHE) data structure within the PostgreSQL database is suitable for any valid 3D spatial model; not yet being explored for other dimensional such as scale environment. Using the same vario-scale approach, the DHE data model is also capable to implement a variable Level of Detail (LoD) representation such as SSC model. Some advantages of the DHE are described in this paper such as the dynamic property (valid updates based on Euler operations) and topology approach in comparison with other existing data structures. The last section of this paper describes capability of the DHE data structure to provide a better platform for GIS integrated space-scale data model.

This paper describes the usage of MUSCLE (Multidirectional Scanning for Line Extraction) Model for automatic generation of 3D networks in CityGML format (from raster floor plans). MUSCLE (Multidirectional Scanning for Line Extraction) Model is a conversion method which was developed to vectorize the straight lines through the raster images including floor plans, maps for GIS, architectural drawings, and machine plans. The model allows user to define specific criteria which are crucial for acquiring the vectorization process. Unlike traditional vectorization process, this model generates straight lines based on a line thinning algorithm, without performing line following-chain coding and vector reduction stages. In this method the nearly vertical lines were obtained by scanning the images horizontally, while the nearly horizontal lines were obtained by scanning the images vertically. In a case where two or more consecutive lines are nearly horizontal or nearly vertical, raster data become unmanageable and the process generates wrongly vectorized lines. In this situation, to obtain the precise lines, the image with the wrongly vectorized lines is diagonally scanned. By using MUSCLE model, the network models are topologically structured in CityGML format. After the generation process, it is possible to perform 3D network analysis based on these models. Then, by using the software that was designed based on the generated models, a geodatabase of the models could be established. This paper presents the correction application in MUSCLE and explains 3D network construction in detail.

Buildings are often modelled as two-dimensional (2D) footprints which are extruded to simple cubes. Buildings are also represented as more complex objects with roofs, facades, etc. – in this case they are polyhedra, sometimes of a complex shape. These allow for visualisation and analysis of a wide area like a city, but micro-scale analysis of interiors is not possible. An example can be rescue operation simulation where information about the internal structure of a building and the external terrain is crucial to improve the response time. It demands a three-dimensional (3D) model where each room is represented as a separate element; there are also doors, windows, walls and other objects that have to be included. Even complex geometrical models can be easily constructed using Computer-Aided Design (CAD) systems. However, lack of semantic information and topological relations makes such models poor choices for GIS analysis. With the new dual half-edge (DHE) data structure and a set of Euler operators a 3D model can be built as in CAD systems, and represented as a cell complex. Construction of non-manifold objects is also possible. An advantage of the DHE is simplicity – only edges and nodes are used. Because of the 3D duality implemented in the structure volumes (cells) and faces are also present in the model. The geometry of a model is constructed explicitly by using Euler operators: connections between elements are created automatically, and semantic information is represented with attributes which can be assigned to any element of the model.

The recently available space-borne SAR sensor, PALSAR, is more promising than its predecessor JERS-1 for biomass estimation because of its long wavelength (L-band), and its ability to provide data with different polarizations, varying incidence angles and higher spatial resolutions. This research investigates the potential of two-date dual polarization (HH and HV) SAR imagery for biomass estimation using different kinds of texture processing and different combinations of single and dual polarization ratios. The investigation is conducted in a mountainous, sub-tropical study area where biomass levels are far beyond the previously recognized saturation levels for L-band SAR images, and forest is a mixture of native and non-native species and plantations. We analyzed two-date SAR data with four steps of image processing, including raw data processing in various combinations, texture measurement parameters of HH and HV polarizations, texture measurement parameters of HH and HV together (both jointly and as a ratio), and a ratio of two-date texture parameters along with a single and two-date ratio. When the processed images were compared with ground data from 50 plots, the performance from raw data processing was low, with adjusted r 2 = 0.22, but after all four processing steps, promising model accuracy (adjusted r 2 = 0.90 and RMSE = 28.58 t/ha) and validation accuracy (using the Leave-One-Out-Cross-Validation) with adjusted r 2 = 0.88 and RMSE = 35.69 t/ha, were achieved from the combination of single- and two-date polarization ratios of texture parameters. The strong performance achieved indicates that L-band dual-polarization (HH and HV) SAR data from PALSAR has great potential for biomass estimation, far beyond the previously reported L-band saturation point for biomass. This result is attributed to the synergy among texture processing and dual polarization on the one hand, which were able to average out random speckle noise, and the use of ratio instead of absolute quantities, due to its well known ability to reduce forest structural and terrain effects. The additional use of two-date SAR data with these processing techniques was able to add complementary information derived from biomass response in both wet and dry seasons. Thus overall, undesirable image noise and terrain effects were reduced.

Traditionally, environment orientations are given via signposts, tour guides, or through the web. However, these methods cannot construct a good personal context-aware knowledge environment. With the advancement of Augmented Reality (AR) and mobile devices, mobile learning or ubiquitous context-aware knowledge, becomes easy and boundary-free. AR technology creates a user-centered, visualized operation, and a real-time-feedback knowledge environment by visualizing virtual objects superimposed with the real world. Meanwhile, context and location aware applications are automatically adapt to the environment of a user, for instance location, time, behavior, or physical condition of a person. This paper focuses on the integration of Augmented Reality and Geographic Information System (GIS) to enhance context and location awarenesslearning in mobile environment. The developed application was able to show significant outcome in a way of which information can be disseminated and presented to the user. For example, nearby features can be easily identified, user can obtained contextual information in real-time, information obtained is more on location-oriented, increases user awareness about events in their locality. Subsequently, it increases the level of self-tour-guide experience and context-aware learning environment.

Road roughness is the deviation of a road surface from a designed surface grade that influences safety conditions for road users. Mobile laser scanning (MLS) systems provide a rapid, continuous and cost-effective way of collecting highly accurate and dense 3D point-cloud data along a route corridor. In this paper an algorithm for the automated estimation of road roughness from MLS data is presented, where a surface grid is fitted to the lidar points associated with the road surface. The elevation difference between the lidar points and their surface grid equivalents provides residual values in height which can be used to estimate roughness along the road surface. Tests validated the new road-roughness algorithm by successfully estimating surface conditions on multiple road sections. These findings contribute to a more comprehensive approach to surveying road networks. Resume La rugosite d'une route est la deviation de la surface de la route par rapport a la surface concue, qui influence les conditions de securite pour les usagers de la route. Le balayage laser mobile (MLS) offre un moyen rapide, continu et rentable pour recueillir des nuages de points 3D tres precis et denses le long d'une route. Cet article presente un algorithme pour l'estimation automatique de la rugosite de la route a partir de donnees MLS, ou une grille est ajustee sur les points lidar censes representer la surface de la route. La difference entre les altitudes des points lidar et de leurs equivalents dans la grille fournit des valeurs residuelles de hauteur qui peuvent etre utilisees pour estimer la rugosite a la surface de la route. Des tests ont valide ce nouvel algorithme en estimant les caracteristiques de la surface sur de multiples sections de route. Ces resultats contribuent a une approche plus globale du releve topographique des reseaux routiers. Zusammenfassung Die Rauhigkeit einer Strassenoberflache ist die qualitative Abweichung der tatsachlichen Oberflache von der geplanten Oberflache. Eine solche Abweichung beeinflust die Sicherheitsbedingungen fur Strasennutzer. Mit Mobile Laserscanning Systemen (MLS) konnen schnell, kontinuierlich und auf kostengunstige Weise hochgenaue und dichte 3D-Punktwolken entlang eines Strasenkorridors erfasst werden. Dieses Paper stellt einen Algorithmus zur automatischen Bestimmung der Oberflachenrauhigkeit in MLS Daten vor. Ein Oberflachenraster wird an die Punkte der Strasenoberflache angepasst. Die Residuen zwischen Lidarpunkten und den entsprechenden Hohen des angepasten Gitters konnen zur Schatzung der Rauhigkeit verwendet werden. In Tests mit verschiedenen Strasenabschnitten wurde der neue Algorithmus hinsichtlich der Schatzung der Oberflachenbeschaffenheit validiert. Auf Basis dieser Ergebnisse kann ein noch umfassender Ansatz zur Erfassung von ganzen Strasennetzen angegangen werden. Resumen La rugosidad de una carretera es la desviacion de la superficie disenada que afecta las condiciones de seguridad de los usuarios de la carretera. Los sistemas de laser moviles proporcionan una manera rapida, continua y barata de recolectar nubes de puntos 3-D densas y de gran precision a lo largo de un corredor. En este articulo se presenta un algoritmo para la estimacion automatica de la rugosidad de la carretera, donde una malla se ajusta a los puntos lidar asociados con la superficie de la carretera. La diferencia entre la elevacion de los puntos lidar y los equivalentes en la malla proporcionan residuos en altura usados para estimar la rugosidad de la superficie a lo largo de la carretera. Las comprobaciones validan el nuevo algoritmo de rugosidad de la carretera al estimar con exito las condiciones de la carretera en diversas secciones de carretera. Estos resultados contribuyen a un enfoque mas amplio de la medida de las caracteristicas de redes de carreteras. 摘要 路面平整度是衡量道路表面和设计表面之差的等级,对道路使用者的安全条件的度量。移动激光扫描(MLS)系统提供了一种快速获取低成本、高精确和高密度的沿着路线走廊的连续三维点云数据的方式。本文提出从MLS数据自动估计路面平整度的算法,该算法利用一个路面格网来拟合激光点云,两者之间在高程上的残差值可以被用来衡量路面平整度。试验充分验证了本文所提出的新算法针对多路段路面平整度处理的可靠性,本文的这些发现为路网测量提供了一种更全面的手段。

In the next few years, 3D data is expected to be an intrinsic part of geospatial data. However, issues on 3D spatial data management are still in the research stage. One of the issues is performance deterioration during 3D data retrieval. Thus, a practical 3D index structure is required for efficient data constellation. Due to its reputation and simplicity, R-Tree has been received increasing attention for 3D geospatial database management. However, the transition of its structure from 2D to 3D had caused a serious overlapping among nodes. Overlapping nodes also occur during splitting operation of the overflown node N of M + 1 entry. Splitting operation is the most critical process of 3D R-Tree. The produced tree should satisfy the condition of minimal overlap and minimal volume coverage in addition with preserving a minimal tree height. Based on these concerns, in this paper, we proposed a crisp clustering algorithm for the construction of a 3D R-Tree. Several datasets are tested using the proposed method and the percentage of the overlapping parallelepipeds and volume coverage are computed and compared with the original R-Tree and other practical approaches. The experiments demonstrated in this research substantiated that the proposed crisp clustering is capable to preserve minimal overlap, coverage and tree height, which is advantageous for 3D geospatial data implementations. Another advantage of this approach is that the properties of this crisp clustering algorithm are analogous to the original R-Tree splitting procedure, which makes the implementation of this approach straightforward.

Topology is one of the mechanisms to describe relationships between spatial objects. Thus, it is the basis for many spatial operations. Models utilizing the topological properties of spatial objects are usually called topological models, and are considered by many researchers as the best suited for complex spatial analysis (i.e., the shortest path search). A number of topological models for two-dimensional and 2.5D spatial objects have been implemented (or are under consideration) by GIS and DBMS vendors. However, when we move to one more dimension (i.e., three-dimensions), the complexity of the relationships increases, and this requires new approaches, rules and representations. This paper aims to give an overview of the 3D topological models presented in the literature, and to discuss generic issues related to 3D modeling. The paper also considers models in object-oriented (OO) environments. Finally, future trends for research and development in this area are highlighted.

In the last few years, 3D urban data and its information are rapidly increased due to the growth of urban area and urbanization phenomenon. These datasets are then maintain and manage in 3D spatial database system. However, performance deterioration is likely to happen due to the massiveness of 3D datasets. As a solution, 3D spatial index structure is used as a booster to increase the performance of data retrieval. In commercial database, commonly and widely used index structure for 3D spatial database is 3D R-Tree. This is due to its simplicity and promising method in handling spatial data. However, 3D R-Tree produces serious overlapping among nodes. The overlapping factor is important for an efficient 3D R-Tree to avoid replicated data entry in a different node. Thus, an efficient and reliable method is required to reduce the overlapping nodes in 3D R-Tree nodes. In this paper, we proposed a 3D geospatial data clustering to be used in the construction of 3D R-Tree and respectively could reduce the overlapping among nodes. The proposed method is tested on 3D urban dataset for the application of urban infill development. By using several cases of data updating operations such as building infill, building demolition and building modification, the proposed method indicates that the percentage of overlapping coverage among nodes is reduced compared with other existing approaches.

Designing 3D navigation systems requires addressing solution methods for complex topologies, 3D modelling, visualization, topological network analysis and so on. 3D navigation within 3D-GIS environment is increasingly growing and spreading to various fields. One of those fields is evacuation through the shortest path with safety in case of disasters such as fire, massive terrorist attacks happening in complex and tall buildings of today’s world. Especially fire with no doubt is one of the most dangerous disaster threatening these buildings including thousands of occupants inside. This chapter presents entire solution methods for designing an intelligent individual evacuation model starting from data generation process. The model is based on Multilayer Perceptron (MLP) which is one of the most preferred artificial neural network architecture in classification and prediction problems. We focus on integration of this model with a 3D-GIS based simulation for demonstrating an individual evacuation process.

Sharing of spatial data using internet is getting common as seen in various developments in Spatial Data Infrastructure (SDI). Spatial data sharing requires standardized file format for interoperability which could be seen in different working groups in Geography Mark-up Language (GML) and CityGML where different level of details (LOD) is described in CityGML for 3D city. In order to solve the large dataset problem that arises due to XML describ-able advantage used in CityGML, a schema-aware encoder (CitySAC) is invented and achieved better compression ratio and required lesser time, compared to the novel Lemper-Zipf-Markov (LZMA) algorithm. Since geometries and semantics data are required in data transaction over the web services especially for analysis, the use case of the proprietor schema-aware encoder is defined. The advantage of the decoder is the availability for code-on-demand. This chapter discusses brief introduction of the schema-aware development background as well as the related works; the development of javascript decoder to solve the interoperability issue in implementing CitySAC over the open web environment as well as the example application.

2D cadastre has been in existence for decades and most countries have found it convenient. However, in complex situations it has been found to be inadequate as ownership becomes difficult to realise. 3D cadastre data was previously not being collected, thus, making such data even more difficult to realise. 3D data collection for 3D cadastre is one of the main issues for practicing surveyors. Several ways of obtaining 3D data exist namely, traditional surveying, terrestrial laser scanning and from Computer Aided Design (CAD) sources. Various data sources have different data structure and a generalized data structure for 3D cadastre hardly reported. A simple and rapid method for indoor data acquisition is proposed. This seeks to determine if the dual half edge data structure is suitable for 3D cadastre. The dual half edge data structure is applied within a graphical user interface. The concept for indoor surveying or data acquisition within the LA_SpatialUnit of the Land Administration Domain Model (LADM) is presented and proposed. Results show inconsistency of Trimble LaserAce 1000 for distance below 5 m with wide and narrow angle of measurement in indoor environment.

With the emerging communication technology in recent years, geospatial data sharing is getting important and popular. Spatial data could be accessed and shared by various stakeholders anytime with the support of a common platform, the Spatial Data Infrastructure (SDI). Data sharing for 3D city building is getting popular using Open Geospatial Consortium (OGC) standard named City Geographic Markup Language (CityGML). Due to human readable schema, data sharing in CityGML often consumes high bandwidth and storage. Transmitting CityGML over web services without compression is not practical. As CityGML represented in Extensible Markup Language (XML) schema, XML compression seemed useful for CityGML. Conventional dictionary compressor such as WinZIP, GZip or BZip could reduce data size; however, the decompressed documents certainly produce the original file, which is still consuming large storage space. This paper discussed the existing 3D-SDI framework, compression techniques and how the schema-aware compressor is developed to achieve a higher compression ratio. The proposed compressor is tested by using Putrajaya city 3D building and results are compared against existing techniques. The results are then decompressed and compared with original 3D buildings by visualizing using CityGML viewer. The future directions are highlighted in the final section.

High quality representation of the topographic and the correct representation of significant urban features would be a fundamental foundation to a better urban flood model. Without such a representation, simulation of flood behaviours would be less successful as the flow patterns were completely dependent on ground levels and the shape of the features. Typically, such data can be obtained via Light Detection and Ranging (LiDAR) surveys. The process of turning raw LiDAR data into a useful Digital Terrain Model (DTM) involves careful processing and application of thinning, filtering and interpolation algorithms. Filtering is a process of automatic detection and interpretation of bare earth and objects from the point cloud of LiDAR data, which results in the generation of a DTM. To date, many filtering algorithms have been developed, and in a more general sense, many of them have become standard industry practice. However, when it comes to the use of a DTM for urban flood modelling applications, these algorithms cannot be always considered suitable. Depending on the terrain characteristics, they can even lead to misleading results and degrade the predictive capability of the modelling technique. This is largely due to the fact that urban environments often contain a variety of features (or objects) such as buildings, elevated roads, bridges, curbs and others which have the ability to store or divert flows during flood events. As these objects dominate urban surfaces, appropriate filtering methods need to be applied in order to identify such objects and to represent them correctly within a DTM so that the DTM can be used more safely in modelling applications. The work described in this chapter concerns improvements of a LiDAR filtering algorithm. The key characteristics of this improved algorithm are: ability to recover curbs and the use of appropriated roughness coefficient of Manning’s value to represent close-to-earth vegetation (e.g. grass and small bush). The results of the improved algorithm were demonstrated using Kuala Lumpur (Malaysia) as a case study. Improvement, in terms of a difference in flood depths and flood flows were observed between the hydraulics models built from several available filtering algorithms and the improved algorithm (MPMA). The overall results suggest that the improvement made in MPMA can lead to some difference in model results, which may in some cases be significant with a tendency towards incorrect flood flow by those models in which such features are not properly represented.

In this research, different texture enhancement methods were investigated and proposed. Rectified perpendicular symmetric photos of 3D objects such as buildings and trees were used to generate the texture for the 3D models. Texture enhancement methods such as higher radiometric adjustment for raised surfaces and Dynamic Pulse Function (DPF) were utilized based on the form of the facade and operators’ observation along with tessellation method. The result of DPF compared with the photorealistic texturing in aspects, quality and data size. The problem of missing faces in a polyhedron and missing object within a CityGML viewer has been solved and described in this chapter. The chapter also describes the development of External code-Lists for objects of the study area which is a starting point for Malaysian Spatial Data Infrastructure (MySDI).

Generally, National Mapping Agencies (NMAs) produce and maintain topographic and cadastral maps. Regular update of map products is the most critical problem faced by NMAs. Therefore, implementation of new technology to automate map generalization has become crucial in updating smaller-scale maps from frequently updated larger-scale maps. Additionally, customized data products can be produced. Implementation of single database and derivation (generalization) of multiple-scale maps from one database can improve the efficiency and maintenance of derived data products. However, consensus between NMAs on a common generalization technique has not been achieved due to incompatibility and complexity of data models. Definitions of terms, technology and organizational structures of the NMAs across the globe are different. This chapter reviews the pertinent generalization efforts made by a number of European NMAs. A framework is proposed based on two correlated models: process-oriented generalization models and object-level-oriented generalization models, which is related to level of map objects. A portion of this framework is implemented and tested on datasets of Kelantan state in Malaysia to produce generalized maps. Generalization operations (e.g., simplification, aggregation, smoothing, etc.) are applied with the aim to generalize polygons and transportation network (e.g., roads, etc.). The proposed framework could be adopted, implemented and tested on datasets maintained by Malaysian National Mapping Agency known as JUPEM (Portal Rasmi Jabatan Ukur Dan Pemetaan Malaysia).

Describing 3D city model over distributed service architecture using Open Geospatial Consortium (OGC) standard, CityGML, is getting popular e.g., Berlin-3D Spatial Data Infrastructure (SDI), Heidelberg-3D SDI, etc. Currently, visualizing 3D city model over the web using X3D is getting common where Web 3D Service (W3DS) publish 3D models in compliance with W3C X3D standard. However, involvement of 3D analysis in 3D SDI environment for Web Processing Service (WPS) requires CityGML whilst this human readable schema often raises issues such as large data that consumes high bandwidth and storage etc. Transmitting CityGML over web services without compression is unpractical due to the typical problem for CityGML. Utilizing conventional compression techniques like WinZIP, GZip, and etc., could reduce large bandwidth consumption for transmitting CityGML over the internet. However, specific schema-aware compression technique shown in this chapter could achieve even higher compression ratio and require lesser time due to utilizing the advantage of parallel programming. Moreover, compressed data is filtered and can be used for smart devices. This distinguishes the advantage using this compressor instead of conventional compression as the filtered data is relatively smaller in file size whilst maintaining essential geometries and attributes information without requiring to decompress back to original file. This chapter discusses how the technique is developed and integrated into simulated Putrajaya 3D SDI, and the results are also illustrated. We also highlight the future directions of the research in the final section.

Generally, cities are expanding due to rapid population growth and require 3D city models for effective town planning, communication and disaster management. Rendering of 3D scenes directly is not so much appropriate as appearance properties, textures and materials attached with city models drastically increase the loading time for visualization and spatial analysis. Additionally, different applications or users demand different Level of Detail (LoDs), thus one of the questions arises—how different LoDs can be made available to these applications? Generation of lower LoDs given by OGC standard CityGML from higher LoDs to reduce data volume is a generalization problem. Relying only on existing geometric-based generalization approaches can result in the elimination or merging of important features, hence, semantic information can be considered. A review of pertinent generalization algorithms proposed by several researchers is presented. Additionally, this paper provides a method for generalization of 3D structures with the aim to derive multiple LoDs keeping semantic information into account. For this purpose, height and positional accuracy of objects at different LoDs provided by CityGML are considered. Initially, building parts and installations are removed. 2D footprints of remaining 3D structures are projected onto ground and simplified to derive LoDs building geometry. An adoption of methods of Sester and Brenner (Continuous generalisation for visualisation on small mobile devices. Heidelberg, pp. 355–368, 2004) extended by Fan et al. (Lecture notes in geoinformation and cartography, advances in giscience. Springer, Heidelberg, pp. 387–405, 2009) are applied for simplification and aggregation of projected footprints. The experiments showed that due to repetition of coordinates of connected nodes in CityGML increase both the rendering time and memory space. However, elimination of important smaller features can be avoided by taking semantic information into account while performing generalization operations.

The need for 3D visualization and navigation within 3D-GIS environment is increasingly growing and spreading to various fields. When we consider current navigation systems, most of them are still in 2D environment that is insufficient to realize 3D objects and obtain satisfactory solutions for 3D environment. One of the most important research areas is evacuating the buildings with safety as more complex building infrastructures are increasing in today’s world. The end user side of such evacuation system needs to run in mobile environment with an accurate indoor positioning while the system assist people to the destination with support of visual landscapes and voice commands. For realizing such navigation system we need to solve complex 3D network analysis. The objective of this paper is to investigate and implement 3D visualization and navigation techniques and solutions for indoor spaces within 3D-GIS. As an initial step and as for implementation a GUI provides 3D visualization of Corporation Complex in Putrajaya based on CityGML data, stores spatial data in a Geo-Database and then performs complex network analysis under some different kind of constraints. The GUI also provides a routing simulation on a calculated shortest path with voice commands and visualized instructions which are intended to be the infrastructure of a voice enabled mobile navigation system in our future work.

In the near future Building Information Modelling will be applied in different areas of the AEC industry. Building Information Models (BIMs) will be used as resources to enable interoperability of software and ‘Building Information Modelling’ based Integrated Project Delivery will be realised as a common process of managing a project over a single shared information backbone. Thus, facilitating the collaborative use of shared BIMs is becoming important in parallel with the industrial demand in the field. Some urban management tasks such as disaster management, delivery of goods and services, and cityscape visualisation are managed by using Geospatial Information Systems as the current state-of-art, as the tasks in these processes require a high level and volume of integrated geospatial information. Several of these tasks such as fire response management require detailed geometric and semantic information about buildings in the form of geospatial information, while tasks such as visualisation of the urban fabric might require less (geometric and semantic) information. Today service-oriented architectures are becoming more popular in terms of enabling integration and collaboration over distributed environments. In this context, this short chapter presents an enhancement for a BIM Web Service pattern (i.e. RESTful BIM) that will help in facilitating information transfer from Building Information Models into the geospatial environment. The chapter starts with the background section later provides a review on the RESTful BIM pattern. Geospatial Views that can be developed for the RESTFul BIM will be elaborated on later in the chapter.

Complexities of streamflow structures, drainage systems, sewers and urban landscape render difficulties for urban flood mitigation and rehabilitation planning towards reducing urban flood disaster. GIS has been useful for the investigation of urban runoff spatial patterns. However, the inability of GIS to realistically explore the momentum and continuity aspects of overland flow and urban runoff process has been proven to be the shortcomings of the system. This leads to the requirement of an extended dimension representing dynamic soft geometrical volumes of urban stormwater runoff. The inclusion of Volumetric Soft Geo-objects (VSG) offers a comprehensive and practical 3D dynamic modeling of urban runoff volume. The VSG are driven based on Kinematic Wave Routing and Green-Ampt method for modeling open channel flow and overland flow volume respectively. Basin model, sub-basin, reach and junction elements are extracted from Digital Elevation Model (DEM) with 5 meter resolution using the HEC-GeoHMS program and the HEC-HMS model. The modeled results of discharge volume gave an R2 of 0.88 and a Nash–Sutcliffe coefficient of 0.82, indicating that VSG provides end-users the prospect to envision complex information of flood disaster management.

Today’s map navigation systems (from 2D to 3D) provide direction instructions in the form of maps, pictograms, and spoken language. However, they are so far not able to support or has very limited access to landmark-based navigation, which the most natural navigation concept is for humans and which also plays an important role for upcoming personal navigation systems. In order to provide such navigation, in this paper, we discuss one of possible solution of modeling visibility in 3D navigation through visual landmarks using Geo-DBMS approach. The aim is to generate measurable visual landmarks along the focus map in a city model which can be used in car or pedestrian navigation system (as web or mobile application). The focus map is obtained from 3D analytical operation (3D buffering from the 3D shortest path analysis result) function within Geo-DBMS. Detailing to the generated measurable visual landmark’s facade, an implementation of dynamic pulse function is then applied. The techniques for choosing specific landmarks and generating the focus maps are shortly presented and their functionality is explained. We tested the proposed approach by using Stuttgart 3D city model. Finally, the paper provides outlook on ideas for future deployment and research.

Effective GIS-based Infiltration Excess Overland Flow (IEOF) simulation and visualization requires good knowledge of GIS core concepts and prediction of soil infiltration rates due to impervious area coverage. The success or failure of GIS-based IEOF simulation and visualization resides initially with the georeference system used. Cartographers have long complained about the poor quality of the output from GIS, which today is generally due not to limitations of the GIS itself but instead to a lack of understanding of cartographic principles among hydrologists and environmentalists. Implementation of soft geo-objects representing flow elements such as streams, mudflows, and runoff provides better dynamic visualization in terms of velocity and direction. Inclusion of volumetric overland flow would help in determining the volume of runoff that hits the flood-plain areas, estimating channel flow capacity, and routing and diversions to reduce effects from flooding. With rapid urbanization, industrialization, and climate change, historical runoff and infiltration rates would provide an improper guide for future enhanced visualization of the current 2D land use surface. This study aims to visualize the influence of georeferencing on IEOF simulation when represented by volumetric soft geo-objects within a 3D environment, which is driven by the physically based Green-Ampt method. Visualization is analyzed by focusing on infiltration and overland flow processes using the conformal-based Malaysian Rectified Skew Orthomorphic (MRSO) and the equidistant-based Cassini-Soldner projection. Appropriate usage of a georeferencing system to visualize 3D dynamic IEOF simulation may see high demand from civil engineers, environmentalists, town planners, geologists, and meteorologists as a basis for producing scientific results in flood management control, sustainability for long-term development purposes, stream restoration, rehabilitation, and hydrologic impact assessment.

3D spatial modeling is one of the most important issues in 3D GIS research. It involves the definition of spatial objects, data models, and attributes for visualization, interoperability and standards. Real world complexity leads to different modeling approaches, as seen in different GIS applications. This paper provides some review of the problems, challenges and issues pertaining to the 3D GIS problems, especially in the handling and managing of 3D solids in DBMS. The paper also describes 3D spatial operators in DBMS and presents results using a simulation dataset. At the end of the paper, we provide and highlight requirements and recommendations for future research.

In this paper, we discuss the problem of 0D feature-in-3D planar polygon. It has been recognized that 3D union and 3D intersections are among important spatial operators in 3D GIS. A 0D feature-in-polygon test is one of the problems in 3D GIS. Though it is a classic problem, however, it has not been addressed appropriately in the literature. Moreover, the 0D feature-in-polygon query is rather complicated if it is implemented into 3D spatial information system. From the aspect of 3D spatial analysis, the general 0D feature-in-3D planar polygon problem should be formulated in a suitable way. Our basic idea is to solve a general 0D feature-in-3D planar polygon problem that includes all special conditions. The method addresses an essential mathematical algorithm that applicable for real objects and provides an approach for implementation in further 3D analytical operation, e.g. 3D union or 3D intersection for 3D GIS.

The needs for three-dimensional (3D) visualization and navigation within 3D-GIS environment are growing and expanding rapidly in a variety of fields. In a steady shift from traditional two-dimensional (2D) GIS toward 3D-GIS, a great amount of accurate 3D data sets (e.g. city models) have become necessary to be produced in a short period of time and provided widely on the market. This requires a number of specific issues to be investigated, e.g. 3D routing accuracy, appropriate means to visualize 3D spatial analysis, tools to effortlessly explore and navigate through large models in real time, with the correct texture and geometry. There had been a lot of study on 3D landscapes, urban and city models. The rapid advancement in science and technology had opened wide options for a change and development of current methods and concepts. Virtual Reality (VR) is one of those developments, which gives the sense of feel in virtual environment. It enables users to visualize, make query and exploring 3D data. Such system can, not only help laymen, who often have trouble in understanding or interpreting complex data, but they also can help experts in decision making. The objective of this paper is to discuss some initial requirements of the proposed solution towards 3D-GIS. Eventually, this paper will serve as a starting point for a more challenging research idea. The focus of this research is to investigate and implementing 3D navigation techniques and solutions for 3D-GIS. Investigation on the support of navigation in real world environment will be carried out. This will include a research on the benefits of using 3D network model (non-planar graph) compared to 2D, how to use visual landmarks in route descriptions and using 3D geometry to get more accurate routing (in buildings, or in narrow street, etc). And as for implementation, a GUI provides the users with means (e.g. fill-out forms) to specify SQL queries interact and visualize 3D outcomes in virtual reality environment. This has opened up the ability to distribute and navigate accurately in 3D virtual worlds. The initial study on Klang Valley will go through data conversion processes from different formats like Laser, VRML, CAD and Shape 3D in a first person view environment using a developed system using VRML, JAVA and .Net compiler. The dataset structure will be in the form of various 2D, 2.5D and 3D array of height fields.

2D cadastre being practice in Malaysia for decades and at the moment it provides vital land and property information like ownerships of the parcels for most parts of the country. The current 2D cadastre system is regularly updated both in rural and in urban areas by the national survey agency (NMA), i.e. the Department of Survey and Mapping (JUPEM). NMA is the responsible agency with survey and mapping to deal on the technical part of producing the cadastral map. They have a very well designed system called Cadastral Database Management System (CDMS) with Digital Cadastral Database (DCDB). On the other hands, the ownership information (who owns what) comes from Land and Mines Offices (PTG) and all these information are considered two-dimensional (2D) in nature. Typical information related to parcels and property ownerships like parcel numbers or IDs, parcel’s geometry and dimensions, etc. are digitally available. In Land Office, they have their own registration system called Computerized Land Registration System (CLRS). Unfortunately, these valuable information being handled by two different agencies in two non-integrated systems. It can be realized that these information still in 2D system and most of the existing 2D cadastre systems are hardly able to provide more realistic and meaningful information to users. With the rapid development of hardware, software and knowledge, we believed Malaysia are ready to develop a 3D Cadastre System to solve the problems with the complexity of cadastral registration of 3D property situations. In Malaysia, hybrid 3D cadastre will be discussed as this model was proposed by previous research work, i.e. Stoter (2004). However, the design system should be realistic and practical to be applied based on Malaysian cadastral environment either on regulation or historically. The aim of this paper is to discuss some initial literature reviews of the subject or problem with respect to current 2D Cadastre System and 2D registration system in Malaysia. The early findings of the problems will be served as starting point in developing and addressing a much bigger problem for a PhD research work.

The establishment of Malaysia cadastral system is to monitor matters of land especially the land ownership. The system is setup to ensure consistency in cadastral information that comes from cadastral survey and cadastral land registration. In general, the cadastral survey and cadastral land registration are managed by Department of Survey and Mapping Malaysia (DSMM) and Land Offices (LO) respectively. The system for land registration is known as Cadastral Data Management System (CDMS) which is controlled by DSMM where as Computerized Land Registration System (CLRS) administered by the Land Office. A cadastre is normally a parcel-based and up-to-date land information system containing a record of interests on land (e.g. rights, restrictions and responsibilities). Currently, the system is based on 2D space. The cadastral object can be either a complete land parcel, parcel of storey houses (strata) e.g. apartments, flats residential or parcel below the surface (stratum). Demands from land owners as well as property owners show that it is insufficient to register cadastral parcel based on 2 D space. Real-estate property is actually in 3D. Current 3D GIS technology could be used to develop a registration system for 3D Cadastre and eventually a solution for complex 3D Cadastre objects or situations. Therefore, the new cadastral system should reflect the existence of the real-world objects - 3D physical objects and have its own legal rights. 3D technologies make it possible to establish 3D cadastre. This paper discusses a development of 3D registration system for cadastre objects in 3D. The main objective is to look into possibility of enhancing the current systems practiced by the DSMM and LO towards 3D cadastre registration. In other words, this research attempts to address one of the aspects in 3D Cadastre, i.e. how to register 3D objects and properties for 3D cadastre.

DBMS becomes very important for GIS as it used to handle large volume of spatial data and could ensure the stability of dataset handling. Next generation of GIS software would highly depend on DBMS in both geometrical modeling and analysis. One of the desired components in such future software or system is the geometric modeling that works with 3D spatial operations. This paper presents a portion of the problems, which are 3D topological operations for DBMS. These operations are very important for 3D spatial analysis. This paper discusses implementation of a 3D data type (Polyhedron) and eight 3D topological relationships between polyhedrons. The relationships are compliant with the 4-intersection model, and it could be extended to 9-intersection model if the exterior component is considered. The implementations are tested for PostgreSQL.