bluuebunny/crossref_metadata_2025 huggingface dataset:
POINT-BASED VERSUS PLANE-BASED SELF-CALIBRATION OF STATIC TERRESTRIAL LASER SCANNERS
Authors: Chow J. C. K. , Lichti D. D. , Glennie C.
Published: September 2012

Abstract. Systematic trends are apparent when studying the self-calibration residuals of many modern static terrestrial laser scanners. Since the operation of terrestrial laser scanners is comparable to an efficient robotic total station, the sensor modelling parameters are developed in the spherical coordinate system where the raw observables of the scanner are range, horizontal angle, and vertical angle. Sensor calibration parameters are already well established for both hybrid and panoramic type laser scanners through the signalized target-based self-calibration method. In this paper, a less labour-intensive and more efficient planar-feature based terrestrial laser scanner self-calibration method, which is more suitable for in-situ self-calibration, is presented. Through simulation it will be demonstrated that the point-based self-calibration and plane-based self-calibration shares many common characteristics. Plane-based self-calibration results from real data captured with the panoramic type Leica HDS6100 and hybrid type Trimble GS200 scanner are also presented to show the practicality of the proposed method and as a comparison to the point-based self-calibration.
ACCURACY ANALYSIS OF KINECT DEPTH DATA
Authors: Khoshelham K.
Published: September 2012

Abstract. This paper presents an investigation of the geometric quality of depth data obtained by the Kinect sensor. Based on the mathematical model of depth measurement by the sensor a theoretical error analysis is presented, which provides an insight into the factors influencing the accuracy of the data. Experimental results show that the random error of depth measurement increases with increasing distance to the sensor, and ranges from a few millimetres up to about 4 cm at the maximum range of the sensor. The accuracy of the data is also found to be influenced by the low resolution of the depth measurements.
GEO-REFERENCED MAPPING USING AN AIRBORNE 3D TIME-OF-FLIGHT CAMERA
Authors: Kohoutek T. K. , Nitsche M. , Eisenbeiss H.
Published: September 2012

Abstract. This paper presents the first experience of a close range bird's eye view photogrammetry with range imaging (RIM) sensors for the real time generation of high resolution geo-referenced 3D surface models. The aim of this study was to develop a mobile, versatile and less costly outdoor survey methodology to measure natural surfaces compared to the terrestrial laser scanning (TLS). Two commercial RIM cameras (SR4000 by MESA Imaging AG and a CamCube 2.0 by PMDTechnologies GmbH) were mounted on a lightweight crane and on an unmanned aerial vehicle (UAV). The field experiments revealed various challenges in real time deployment of the two state-of-the-art RIM systems, e.g. processing of the large data volume. Acquisition strategy and data processing and first measurements are presented. The precision of the measured distances is less than 1 cm for good conditions. However, the measurement precision degraded under the test conditions due to direct sunlight, strong illumination contrasts and helicopter vibrations.
LAND-BASED MOBILE LASER SCANNING SYSTEMS: A REVIEW
Authors: Puente I. , González-Jorge H. , Arias P. , Armesto J.
Published: September 2012

Abstract. Mobile mapping has been using various photogrammetric techniques for many years. In recent years, there has been an increase in the number of mobile mapping systems using laser scanners available in the market, partially because of the improvement in GNSS/INS performance for direct georeferencing. In this article, some of the most important land-based mobile laser scanning (MLS) systems are reviewed. Firstly, the main characteristics of MLS systems vs. airborne (ALS) and terrestrial laser scanning (TLS) systems are compared. Secondly, a short overview of the mobile mapping technology is also provided so that the reader can fully grasp the complexity and operation of these devices. As we put forward in this paper, a comparison of different systems is briefly carried out regarding specifications provided by the manufacturers. Focuses on the current research are also addressed with emphasis on the practical applications of these systems. Most of them have been utilized for data collection on road infrastructures or building façades. This article shows that MLS technology is nowadays well established and proven, since the demand has grown to the point that there are several systems suppliers offering their products to satisfy this particular market.
AREA-BASED SNOW DAMAGE CLASSIFICATION OF FOREST CANOPIES USING BI- TEMPORAL LIDAR DATA
Authors: Vastaranta M. , Korpela I. , Uotila A. , Hovi A. , Holopainen M.
Published: September 2012

Abstract. Multitemporal LiDAR data provide means for mapping structural changes in forest canopies. We demonstrate the use of area-based estimation method for snow damage assessment. Change features of bi-temporal LiDAR point height distributions were used as predictors in combination with in situ training data. In the winter 2009–2010, snow damages occurred in Hyytiälä (62°N, 24°E), southern Finland. Snow load resulted in broken, bent and fallen trees changing the canopy structure. The damages were documented at the tree level at permanent field plots and dense LiDAR data from 2007 and 2010 were used in the analyses. A 5 × 5-m grid was established in one pine%ndash;spruce stand and change metrics from the LiDAR point height distribution were extracted for the cells. Cells were classified as damaged (n = 43) or undamaged (n = 42) based on the field data. Stepwise logistic regression detected the damaged cells with an overall accuracy of 78.6% (Kappa = 0.57). The best predictors were differences in h-distribution percentage points 5, 35, 40, 50 and 70 of first-or-single return data. The tentative results from the single stand suggest that dense bi-temporal LiDAR data and an area-based approach could be feasible in mapping canopy changes. The accuracy of the point h-distribution is dependent on the pulse density per grid cell. Depending on the time span between LiDAR acquisitions, the natural changes of the h- distributions due to tree growth need to be accounted for as well as differences in the scanning geometry, which can substantially affect the LiDAR h-metrics.
LIDAR PHOTOGRAMMETRY AND ITS DATA ORGANIZATION
Authors: Hu X. , Zhang Z. , Duan Y. , Zhang Y. , Zhu J. , Long H.
Published: September 2012

Abstract. Light detection and ranging (LiDAR) is a technology capable of measuring geo-referenced coordinate of object points in a straightforward way. It has been widely used in mapping projects in last 20 years. LiDAR and photogrammetry has their own advantages and disadvantages that compensate for each other very well. The combination of the two definitely can achieve more efficient and precise acquisition of geospatial information. Nowadays main LiDAR system vendors are providing integrated laser scanning and camera sensors in many of their systems (or at least offering camera as optional equipment). This makes seamlessly integrating the two technologies possible, but the potential of the integrated system has to be explored yet. In this paper we propose a new subject – LiDAR photogrammetry based on the integrated sensor system and discuss its research scope and fundamental topics (or techniques to be developed). Organizing integrated data properly is the first step in LiDAR photogrammetry because existing image and LiDAR point cloud data are organized separately that leads to inefficient data access and usage in processing. Based on the extension of LAS format we propose a new data organization scheme called DPL format. Examples are given to show advantages of the new data organization method.
A LOW BUDGET MOBILE LASER SCANNING SOLUTION USING ON BOARD SENSORS AND FIELD BUS SYSTEMS OF TODAY'S CONSUMER AUTOMOBILES
Authors: Vock D. M. M. , Jungmichel M.
Published: September 2012

Abstract. Mobile laser scanning systems (MLS) offer a great potential for acquiring detailed point cloud data of urban and suburban surroundings with minimum effort. In this paper a new solution for MLSs is presented, requiring solely a combination of a profile laser scanning device and systems that are included in today's serialized end consumer vehicles. While today's mobile laser scan systems require different and expensive additional hardware that needs to be mounted onto the vehicle, the devices included within vehicle electronics offer good alternatives without additional costs.The actual scan consists of a continuous profile scan together with information gathered from on-board sensor modules. In a post- processing step, the sensor data is used to reconstruct the car's trajectory for the period of the scan and, based on this information, the track of the scan device for every measured laser pixel. Synchronization of pixel data and vehicle movement is realized via a timestamp signal which is transmitted to the car's field bus system and the scan device. To generate the final point cloud scenario, the trajectory is interpolated for every single scan point and used to convert its local position within the profile into the global coordinate system (Fig.1, Left).
A DATA MANAGEMENT METHOD FOR EFFICIENT SEARCH AND RENDERING OF MULTIPLE LARGE SCALE POINT CLOUDS
Authors: Maeno T. , Date H. , Kanai S.
Published: September 2012

Abstract. Recently, with the progress of laser scanning technology, it has become possible to scan several environments such as buildings, roads, and cities easily and at a low cost. There are typically three scanning methods: TLS (Terrestrial Laser Scanning), MMS (Mobile Mapping System), and ALS (Airborne Laser Scanning), and the environments are scanned for measurement, modelling, and simulation etc. Therefore, an efficient and comprehensive data management method, which can handle these point clouds in various applications is strongly required. In this paper, we describe a method of data management for efficient search and rendering of multiple large scale point clouds. First, we define a general point cloud file format including the octree and the quantization structure. Next, the data management method enabling an efficient search and rendering of the point clouds is proposed. Finally, the effectiveness of our method is verified using several actual data sets.
ESTIMATION OF VERTICAL DEFLECTIONS IN CONCRETE BEAMS THROUGH DIGITAL CLOSE RANGE PHOTOGRAMMETRY
Authors: Detchev I. , Habib A. , El-Badry M.
Published: September 2012

Abstract. Deformation monitoring, and in general structural health monitoring, of civil infrastructure systems is important in terms of both safety and serviceability. Traditionally, large structures have been monitored using surveying techniques, while fine-scale monitoring of structural components has been done with geotechnical instrumentation. This paper reviews the advantages and disadvantages of using remote sensing methods, such as terrestrial laser scanning and digital close range photogrammetry, for the purposes of precise 3D reconstruction and the estimation of deflections in structural materials. It is also shown how a low-cost setup of multiple digital cameras and projectors can be used for the monitoring of concrete beams subjected to different loading conditions by a hydraulic actuator. The photogrammetric system used does not require any physical targets other than for the purposes of establishing the relative orientation between the involved cameras. The setup was tested in two experiments, and the beam deflections resulted from the photogrammetric system were compared to the ones from a set of one-dimensional laser transducers and a terrestrial laser scanner. The experiments proved that it was possible to detect sub-millimetre level deformations given the used equipment and the geometry of the setup.
VERTICAL VEGETATION STRUCTURE ANALYSIS AND HYDRAULIC ROUGHNESS DETERMINATION USING DENSE ALS POINT CLOUD DATA - A VOXEL BASED APPROACH
Authors: Vetter M. , Höfle B. , Hollaus M. , Gschöpf C. , Mandlburger G. , Pfeifer N. , Wagner W.
Published: September 2012

Abstract. In this contribution the complexity of the vertical vegetation structure, based on dense airborne laser scanning (ALS) point cloud data (25 echoes/m2 ), is analyzed to calculate vegetation roughness for hydraulic applications. Using the original 3D ALS point cloud, three levels of abstractions are derived (cells, voxels and connections) to analyze ALS data based on a 1×1 m2 raster over the whole data set. A voxel structure is used to count the echoes in predeﬁned detrended height levels within each cell. In general, it is assumed that the number of voxels containing echoes is an indicator for elevated objects and consequently for increased roughness. Neighboring voxels containing at least one data point are merged together to connections. An additional height threshold is applied to connect vertical neighboring voxels with a certain distance in between. Thus, the connections indicate continuous vegetation structures. The height of the surface near or lowest connection is an indicator for hydrodynamic roughness coefﬁcients. For cells, voxels and connections the laser echoes are counted within the structure and various statistical measures are calculated. Based on these derived statistical parameters a rule-based classiﬁcation is developed by applying a decision tree to assess vegetation types. Roughness coefﬁcient values such as Manning's n are estimated, which are used as input for 2D hydrodynamic-numerical modeling. The estimated Manning’s values from the ALS point cloud are compared with a traditional Manning's map. Finally, the effect of these two different Manning's n maps as input on the 2D hydraulics are quantiﬁed by calculating a height difference model of the inundated depth maps. The results show the large potential of using the entire vertical vegetation structure for hydraulic roughness estimation.
AUTOMATIC RECOGNITION OF PIPING SYSTEM FROM LARGE-SCALE TERRESTRIAL LASER SCAN DATA
Authors: Kawashima K. , Kanai S. , Date H.
Published: September 2012

Abstract. Recently, changes in plant equipment have been becoming more frequent because of the short lifetime of the products, and constructing 3D shape models of existing plants (as-built models) from large-scale laser scanned data is expected to make their rebuilding processes more efficient. However, the laser scanned data of the existing plant has massive points, captures tangled objects and includes a large amount of noises, so that the manual reconstruction of a 3D model is very time-consuming and costs a lot. Piping systems especially, account for the greatest proportion of plant equipment. Therefore, the purpose of this research was to propose an algorithm which can automatically recognize a piping system from terrestrial laser scan data of the plant equipment. The straight portion of pipes, connecting parts and connection relationship of the piping system can be recognized in this algorithm. Eigenvalue analysis of the point clouds and of the normal vectors allows for the recognition. Using only point clouds, the recognition algorithm can be applied to registered point clouds and can be performed in a fully automatic way. The preliminary results of the recognition for large-scale scanned data from an oil rig plant have shown the effectiveness of the algorithm.
AUTOMATIC REGISTRATION OF MULTIPLE LASER SCANS USING PANORAMIC RGB AND INTENSITY IMAGES
Authors: Alba M. , Barazzetti L. , Scaioni M. , Remondino F.
Published: September 2012

Abstract. This paper presents an automated methodology able to register laser scanning point clouds using their panoramic images derived from intensity values or RGB data, the latter obtained from a co-registered camera. Starting from the panorama of each laser scan, a Feature-Based Matching (FBM) algorithm is pairwise applied to extract corresponding key-points. Robust estimators are then used to remove outliers through a generalized rejection procedure encompassing several geometric models. After tracking the twofold key- points across different scan pairs in order to increase the local redundancies, a global Least Squares block adjustment is computed for all scans. Ground control points can also be included at this stage for datum definition and control of block’s stability. The proposed method was tested on real case studies and the experiments showed that the procedure is able to deliver the registration of all scans in a fully automatic way. On the other hand, if a higher accuracy is required this solution needs a further ICP refinement.
APPLYING 3D AFFINE TRANSFORMATION AND LEAST SQUARES MATCHING FOR AIRBORNE LASER SCANNING STRIPS ADJUSTMENT WITHOUT GNSS/IMU TRAJECTORY DATA
Authors: Ressl C. , Pfeifer N. , Mandlburger G.
Published: September 2012

Abstract. In this article we extend our previous work on the topic of ALS strip adjustment without GNSS/IMU trajectory data. Between overlap- ping strip pairs the relative orientation as a 3D afﬁne transformation is estimated by a 3D LSM approach, which uses interpolated 2.5D grid surface models of the strips and the entire strip overlap as one big LSM window. The LSM derived relative orientations of all strip pairs in the block together with their covariance matrices are then used simultaneously as observations in an adjustment following the Gauss-Helmert model. This way the exterior orientation of each strip is computed, which refers to a relative block system. If proper ground control data is given, then an absolute orientation of the block of strips can be computed by a ﬁnal LSM run. In a small example consisting of 4 strips with ca. 70% overlap the improvement in the relative geometric accuracy is demonstrated by the decreasing óMAD of the height differences from 8.4cm (before) to 1.6cm (after the strip adjustment).
LYNX MOBILE MAPPER FOR SURVEYING CITY CENTERS AND HIGHWAYS
Authors: Conforti D. , Zampa F.
Published: September 2012

Abstract. In the last two years the Lynx Mobile Mapper has become the new lidar solution developed for surveying large areas that are impractical with static lidar sensors and require an accuracy and resolution that exceed airborne technologies. The system allows the scanning at a speed up to 100 km/h, obtaining accuracy better than 5 cm with an up to 7 mm resolution. Therefore, this solution proves to be an excellent tool for surveying city centers, highways, railways, thanks also to a very fast, safe and accurate data collection. This paper will present two applications: 1- The survey of the entire ancient city center of Brescia (Italy) with it medieval castle, the narrows streets and the main squares. It also has been run a test to survey with the Lynx the tunnel that go underneath the castle and compare the result with a static laser scanner survey, 2- The survey of the Calatrava Bridge on the A1 highway. The central bridge, which crosses over the high-speed rail line and the A1 motorway is composed as a single symmetrical arch, placed longitudinally, which rises to a height of 46m. During the survey the two A1 motorway carriageways have been scanned and the upper part of the bridge for a complete 3D model of this structure.
USING TERRESTRIAL LASER SCANNING AND LIDAR DATA FOR PHOTO-REALISTIC VISUALISATION OF CLIMATE IMPACTS AT HERITAGE SITES
Authors: Nettley A. , Anderson K. , De Silvey C. , Caseldine C.
Published: September 2012

Abstract. Remote sensing technologies such as terrestrial laser scanning (TLS) and light detection and ranging (LIDAR) can now provide accurate spatial data for describing topographic patterns in landscapes and mapping the fine geometric detail of complex structures. Interdisciplinary studies using such data for characterising heritage sites are now widespread, but it is less common for data derived from these technologies to be used in an operational setting to 'engage' local people with the idea of future change. Three- dimensional landscape models using TLS and LIDAR are a powerful way of communicating climate change to lay audiences on a local level and the use of multi-scale spatial data can help to show the anticipated impacts of climate change at heritage sites. The aim of this paper is to present the results of a project designed to produce a photorealistic geospatial model of the historic quayside at Cotehele Quay, Cornwall, UK. Our central aim was to generate a spatially accurate and visually realistic three-dimensional model of the site for use in local engagement strategies. TLS and LIDAR data were collected and processed to produce a three-dimensional model. The key image processing stages included: registration to a national co-ordinate system, meshing using 3D reshaper and visualisation creation in 3DS Max. The resulting model will permit spatial consideration of the impact of management strategies at the site. The over-arching application of this method beyond the study site will provide a platform for discussion that addresses the needs of site managers and the expectations of local communities.
REVERSE ENGINEERING AND 3D MODELLING FOR DIGITAL DOCUMENTATION OF MARITIME HERITAGE
Authors: Menna F. , Nocerino E. , Scamardella A.
Published: September 2012

Abstract. heritage in general. Despite this has been stressed with emphasis, three dimensional modelling of maritime cultural heritage is still not usual as for archaeology and architecture. Three-dimensional modelling in the maritime heritage needs particular requirements. Objects to be recorded range from small replicas in maritime museums up to full-scale vessels still in operation. High geometric accuracy, photorealism of final model and faithful rendering of salient details are usually needed, together with the classical requisites characterising the 3D modelling-from-reality process, i.e. automation, low cost, reliability and flexibility of the modelling technique. In this paper, a hybrid multi-technique approach is proposed for maritime heritage preservation and, as case study, the 3D modelling of a 3-meter-long scale model of a historic warship, the "Indomito", is presented. The survey is placed in a wider project aiming to realize the virtual maritime museum of Parthenope University of Naples, for making it available to a wider public and also preserving its cultural heritage. Preliminary results are presented and discussed, highlighting relevant aspects that emerged during the experiment.
COMPARING TIME-OF-FLIGHT AND PHASE-SHIFT. THE SURVEY OF THE ROYAL PANTHEON IN THE BASILICA OF SAN ISIDORO (LEÓN)
Authors: San José Alonso J. I. , Martínez Rubio J. , Fernández Martín J. J. , García Fernández J.
Published: September 2012

Abstract. The appearance of the Terrestrial Laser Scanners or 3D Scanners in Heritage recording has been relatively recent and it is submitted to a constant evolution determined mainly by the big technological advance in fields like Optics, Signal Processing, Electronics and Computer Science. As they have become popular so suddenly, it is essential to study the behavior of these evolving devices in a variety of scenarios to support an accurate assessment of their capabilities. Until two years ago, TOF (time-of-flight) and PS (phase-shift) technologies could hardly be considered side by side comparable, at least under equal terms and requirements. The first enables much longer ranges, while the latter dominated the short distances producing more accurate data with very high acquisition rates. Today, in a sort of convergent career, the scope of phase-shift technology has grown to near 200 meters and the time-of-flight team have been increasing their speed to figures as 100,000 points per second. In this article we expose the results of the comparison between the data delivered by two scanners based on the two related technologies that categorize today's both long and medium-range scanners. The two have been opposed face to face in the survey of the so called "the Sistine Chapel of the Spanish Romanesque" during the same day, and under the same environmental conditions, using equivalent capture settings. But now that as we noted these technologies can fight in the same arena, can we claim to be able to produce similar results whatever which one we choose? The answer is "no" or a "conditioned yes" at least. Let’s leave numbers and nominal specifications behind and see what else makes them behave so differently.
THREE-DIMENSIONAL DATA AND THE RECORDING OF MATERIAL STRUCTURE
Authors: Parenti R. , Gilento P. , Ceccaroni F.
Published: September 2012

Abstract. The “description” of a material structure requires a high degree of objectivity to serve the scientific interests of certain disciplines (archeological documentation, conservation and restoration, safeguarding of cultural assets and heritage). Geometric data and photographic documentation of surfaces are thus the best instruments for efficacious, clear and objective recording of architectural objects and other anthropic manifestations. In particular, the completeness and diachrony of photographic documentation has always proven essential in recording the material structure of historical buildings.The aim of our contribution is to show the results of several projects carried out with the aid of survey methodologies that utilize digital photographic images to generate RGB (ZScan) point clouds of architectural monuments (urban standing buildings, monuments in archaeological areas, etc.) and art objects. These technologies allow us to capture data using digital photogrammetric techniques; although not based on laser scanners, they can nonetheless create dense 3D point clouds, simply by using images that have been obtained via digital camera. The results are comparable to those achieved with laser scanner technology, although the procedures are simpler, faster and cheaper. We intend to try to adapt these technologies to the requirements and needs of scientific research and the conservation of cultural heritage. Furthermore, we will present protocols and procedures for data recording, processing and transfer in the cultural heritage field, especially with regard to historical buildings. Cooperation among experts from different disciplines (archaeology, engineering and photogrammetry) will allow us to develop technologies and proposals for a widely adoptable workflow in the application of such technologies, in order to build an integrated system that can be used throughout the scientific community. Toward this end, open formats and integration will be taken into account as far as data processing and transfer are concerned.
3D VIRTUAL ANASTYLOSIS AND RECONSTRUCTION OF SOME BUILDINGS IN THE SITE OF SAINT-SIMEON, SYRIA
Authors: Kurdy M. , Biscop J-L. , De Luca L. , Florenzano M.
Published: September 2012

Abstract. The site of Qal'at Sem'an, located in the north of Syria, was built in the honor of Saint Simeon around the column on the top of which he lived many years and died in 459. Since 2003, this site has been the object of digital surveys which covered the major part of the area. The sanctuary (Qal'at Sem'an) and the village (Deir Sem'an) are composed of different types of edifices; this variety gives us a large field of studies. Several surveying methods were applied on these sectors according to the morphology of the analyzed parts and to the analysis needs. This article presents a case study based on a combination of different digital measurement and modeling techniques for the virtual reconstruction of various parts of this complex site. As this work is conducted over several years, different acquisition tools have been experimented for image-based and range-based 3D modeling. In particular, we focus on the "Residence", a civil building of the 6th century which probably was an oil mill. We will describe the anastylosis process founded firstly on the digital surveying, secondly on the 3D model structuring and finally on the information interfacing by using NUBES, an integrated platform for describing, analyzing, documenting and sharing digital representations of heritage buildings. The final goal of our work is to evaluate the relevance of the survey / modeling / semantic structuring workflow for an effective analysis of a complex site.
SPIDERGL: A GRAPHICS LIBRARY FOR 3D WEB APPLICATIONS
Authors: Di Benedetto M. , Corsini M. , Scopigno R.
Published: September 2012

Abstract. The recent introduction of the WebGL API for leveraging the power of 3D graphics accelerators within Web browsers opens the possibility to develop advanced graphics applications without the need for an ad-hoc plug-in. There are several contexts in which this new technology can be exploited to enhance user experience and data fruition, like e-commerce applications, games and, in particular, Cultural Heritage. In fact, it is now possible to use the Web platform to present a virtual reconstruction hypothesis of ancient pasts, to show detailed 3D models of artefacts of interests to a wide public, and to create virtual museums. We introduce SpiderGL, a JavaScript library for developing 3D graphics Web applications. SpiderGL provides data structures and algorithms to ease the use of WebGL, to define and manipulate shapes, to import 3D models in various formats, and to handle asynchronous data loading. We show the potential of this novel library with a number of demo applications and give details about its future uses in the context of Cultural Heritage applications.
X3DOM AS CARRIER OF THE VIRTUAL HERITAGE
Authors: Jung Y. , Behr J. , Graf H.
Published: September 2012

Abstract. Virtual Museums (VM) are a new model of communication that aims at creating a personalized, immersive, and interactive way to enhance our understanding of the world around us. The term "VM" is a short-cut that comprehends various types of digital creations. One of the carriers for the communication of the virtual heritage at future internet level as de-facto standard is browser front-ends presenting the content and assets of museums. A major driving technology for the documentation and presentation of heritage driven media is real-time 3D content, thus imposing new strategies for a web inclusion. 3D content must become a first class web media that can be created, modified, and shared in the same way as text, images, audio and video are handled on the web right now. A new integration model based on a DOM integration into the web browsers' architecture opens up new possibilities for declarative 3 D content on the web and paves the way for new application scenarios for the virtual heritage at future internet level. With special regards to the X3DOM project as enabling technology for declarative 3D in HTML, this paper describes application scenarios and analyses its technological requirements for an efficient presentation and manipulation of virtual heritage assets on the web.
EUROPEANA AND 3D
Authors: Pletinckx D.
Published: September 2012

Abstract. The current 3D hype creates a lot of interest in 3D. People go to 3D movies, but are we ready to use 3D in our homes, in our offices, in our communication? Are we ready to deliver real 3D to a general public and use interactive 3D in a meaningful way to enjoy, learn, communicate? The CARARE project is realising this for the moment in the domain of monuments and archaeology, so that real 3D of archaeological sites and European monuments will be available to the general public by 2012. There are several aspects to this endeavour. First of all is the technical aspect of flawlessly delivering 3D content over all platforms and operating systems, without installing software. We have currently a working solution in PDF, but HTML5 will probably be the future. Secondly, there is still little knowledge on how to create 3D learning objects, 3D tourist information or 3D scholarly communication. We are still in a prototype phase when it comes to integrate 3D objects in physical or virtual museums. Nevertheless, Europeana has a tremendous potential as a multi-facetted virtual museum. Finally, 3D has a large potential to act as a hub of information, linking to related 2D imagery, texts, video, sound. We describe how to create such rich, explorable 3D objects that can be used intuitively by the generic Europeana user and what metadata is needed to support the semantic linking.
GIS ADOPTION AND DIFFUSION AMONG SENIOR HIGH SCHOOL GEOGRAPHY TEACHERS IN TAIWAN
Authors: Lay J. G. , Chen Y. W.
Published: September 2012

Abstract. The crux of this paper lies in exploring geographic information system (GIS) adoption and diffusion among high school geography teachers in Taiwan. Because the integration of GIS in the high school curriculum is relatively new, we assume that high school geography teachers require resources, training, and assistance in learning GIS and in developing modules that can be incorporated into their teaching. A number of in-service training programs have been created to this end. We aim to study what motivates geography teachers to learn GIS during in-service training. The adoption of GIS has been studied in countries such as the U.S. and Singapore; however, as there is presently no literature on Taiwan's experience, we intend to fill this gap. This is achieved through statistical analysis of primary data gleaned from a census of Taiwan's high school geography teachers. The design of the questionnaire is largely inspired by an existing measurement of two commonly cited theoretical models. The technology acceptance model (TAM) and its various modifications focus on teachers' perceived usefulness (PU) and perceived ease of use (PEOU). The social influence model (SIM), differently, postulates that teachers' usage of GIS is affected by peers and their schools. Using the census data, we provide a preliminary analysis of these two models in this paper.
ALPINE VEGETATION ECOTONE DYNAMICS IN GANGOTRI CATCHMENT USING REMOTE SENSING TECHNIQUES
Authors: Singh C. P. , Panigrahy S. , Parihar J. S.
Published: September 2012

Abstract. Analysis of the satellite imagery reveals two different perspectives of the vegetation ecotone dynamics in Gangotri catchment. On one hand, there is evidence of upward shift in the alpine tree and vegetation ecotone over three decades. On the other hand, there has been densification happening at the past treeline. The time series fAPAR data of two decades from NOAA-AVHRR confirms the greening trend in the area. The density of trees in Chirbasa has gone up whereas in Bhojbasa there is no significant change in NDVI but the number of groves has increased. Near Gaumukh the vegetal activity has not shown any significant change. We found that the treeline extracted from satellite imagery has moved up about 327±80m and other vegetation line has moved up about 401±77m in three decades. The vertical rate of treeline shift is found to be 11m/yr with reference to 1976 treeline; however, this can be 5m/yr if past toposheet records (1924 – 45) are considered as reliable reference. However, the future IPCC scenario based bioclimatic fundamental niche modelling of the Betula utilis (a surrogate to alpine treeline) suggests that treeline could be moving upward with an average rate of 3m/yr. This study not only confirms that there is an upward shift of vegetation in the alpine zone of Himalayas, but also indicate that old vegetation ecotones have grown denser
ANALYSIS OF SEASONAL AND ANNUAL CHANGE OF VEGETATION IN THE INDIAN THAR DESERT USING MODIS DATA
Authors: Santra P. , Chkraborty A.
Published: September 2012

Abstract. The western part of India, specifically the dry region, will play an important role in determining the Indian monsoon and even global climate patterns. Drastically change in land use pattern of the region has been observed during last few decades. In this paper, an effort was made to track the seasonal as well as annual changes of vegetation pattern in Jaisalmer district using MODIS normalized difference vegetation index (NDVI) products. Apart from this, ground data on vegetation were also collected under vegetation carbon pool assessment programme of ISRO-IGBP. It was found that during the hot summer month of May, the area under NDVI class 0–0.1 is reduced from 98% during 2003 to 95% during 2009 with a simultaneous increase in area under NDVI class 0.1–0.2 from 2 to 5%. During the month of September, area under NDVI class 0.2–0.3 increased from almost negligible during May to 34–39% during normal or surplus rainfall year but only to 3% during a deficit year. From the ground data on vegetation biomass, it was found that Prosopis juliflora and Acacia senegal are the most abundant trees in Jaisalmer region of the desert. The sites with NDVI value ≥ 0.2 were mostly found with Prosopis juliflora tree. Among shrubs, the most abundant species was Calotropis procera and Zizyphus numularia. From this study, it has been found that MODIS NDVI products may be used to quickly assess the vegetation changes in response to rainfall as well as due to anthroprogenic interventions in desert.
MULTI-DECADAL FLUVIO-GEOMORPHOLOGICAL AND BANKLINE CHANGES OF THE GANGA RIVER AROUND BALLIA AND RUDRAPUR USING REMOTE SENSING AND GIS TECHNIQUES
Authors: Desai A. J. , Arya A. S. , Shah R. D.
Published: September 2012

Abstract. Fluvial landforms are developed due to river action and these processes help in understanding the development of various landforms on the earth's surface. Gangetic plain is vast alluvial tract made up of sand, silt and clay. This region receives heavy rainfall causing flash floods which results in bank-line shifting as well as various fluvio-geomorphological changes. Fluvial processes such as erosion and deposition not only play an important role in shaping of different fluvial landscapes but also contribute towards the braiding and meandering pattern which causes change in the flow pattern of the river channel. Transportation and deposition of the suspended load also contributes towards such changes. The present work describes various fluvio-geomorphological features and their changes during different time intervals in and around Ballia and Rudrapur. The paper also deals in understanding the problems like bank-line shifting, erosion and deposition caused by the continuous change in the fluvial patterns, bank erosion and sedimentation in this region over past 8 decades.
AUTOMATED ALGORITHM FOR EXTRACTION OF WETLANDS FROM IRS RESOURCESAT LISS III DATA
Authors: Subramaniam S. , Saxena M.
Published: September 2012

Abstract. Wetlands play significant role in maintaining the ecological balance of both biotic and abiotic life in coastal and inland environments. Hence, understanding of their occurrence, spatial extent of change in wetland environment is very important and can be monitored using satellite remote sensing technique. The extraction of wetland features using remote sensing has so far been carried out using visual/ hybrid digital analysis techniques, which is time consuming. To monitor the wetland and their features at National/ State level, there is a need for the development of automated technique for the extraction of wetland features. A knowledge based algorithm has been developed using hierarchical decision tree approach for automated extraction of wetland features such as surface water spread, wet area, turbidity and wet vegetation including aquatic for pre and post monsoon period. The results obtained for Chhattisgarh, India using the automated technique has been found to be satisfactory, when compared with hybrid digital/visual analysis technique.
MONITORING OF STRUCTURAL COMPONENTS AND WATER BALANCE AS AN AID TO WETLAND MANAGEMENT USING GEOSPATIAL TECHNIQUES – A CASE STUDY FOR NALSAROVAR LAKE, GUJARAT
Authors: Murthy T. V. R. , Panigrahy S.
Published: September 2012

Abstract. The hydrologic variability greatly influences the structural components of wetlands that have a great bearing on habitats for avifauna, aquatic fauna including fish etc. This paper highlights the results of a study carried out to derive changes in open-water and vegetation, and also water balance for Nalsarovar Lake, Gujarat. MODIS 8-day composite data for three consecutive years viz 2002/03, 2003/04 and 2004/05 were used to study the seasonal and inter annual dynamics of water regime in the lake. Digital elevation model derived using Shuttle Radar Topographic Mission data with interpolated bottom topography was used to generate elevation contours and compute water volume from water spread data. The reference data of 2002 (drought year) shows the maximum extent of wetland to be 8.06 km2 with emergent vegetation of recorded as 2.36 km2 and open-water as 5.70 km2. The rainfall has an impact on the preferred habitat availability for various species of avifauna and it is noted that emergent vegetation present in the lake completely dried up by summer 2002, a rainfall deficit year but revived again in the preceding year i.e. 2003 which was a good rainfall year with 46.68 km2 under emergent vegetation and 61.96 km2 under open-water. The 2002 being a drought year has shown very low reference storage (0.256 MCM), which has shown a gradual decrease in the storage to 0.00019 MCM in March 2003. The reference storage also registered a steep increase to 18.165 MCM in October 2003 and decreased 1.264 MCM in March 2004. From this study it is evident that water level of about 9 m elevation at the end of the rainy season is found to be optimal for maintaining various habitats that in turn support the avifauna for the rest of the lean period.
ASSESSMENT OF EARLY SEASON AGRICULTURAL DROUGHT THROUGH LAND SURFACE WATER INDEX (LSWI) AND SOIL WATER BALANCE MODEL
Authors: Chandrasekar K. , Sesha Sai M. V. R. , Behera G.
Published: September 2012

Abstract. An attempt was made to address the early season agriculture drought, by monitoring the surface soil wetness during 2010 cropping seasons in the states of Andhra Pradesh and Tamil Nadu. Short Wave Infrared (SWIR) based Land Surface Water Index (LSWI) and Soil Water Balance (SWB) model using inputs from remote sensing and ancillary data were used to monitor early season agriculture drought. During the crop season, investigation was made on LSWI characteristics and its response to the rainfall. It was observed that the Rate of Increase (RoI) of LSWI was the highest during the fortnights when the onset of monsoon occurred. The study showed that LSWI is sensitive to the onset of monsoon and initiation of cropping season. The second part of this study attempted to develop a simple book keeping – bucket type – water tight soil water balance model to derive the top 30cm profile soil moisture using climatic, soil and crop parameters as the basic inputs. Soil moisture derived from the model was used to compute the Area Conducive for Sowing (ACS) during the sowing window of the cropping season. The soil moisture was validated spatially and temporally with the ground observed soil moisture values. The ACS was compared with the RoI of LSWI. The results showed that the RoI was high during the sowing window whenever the ACS was greater than 50% of the district area. The observation was consistent in all the districts of the two states. Thus the analysis revealed the potential of LSWI for early season agricultural drought management.
DIURNAL AND SEASONAL VARIATION OF MEASURED ATMOSPHERIC CO2 AT DEHRADUN DURING 2009
Authors: Sharma N. , Nayak R. K. , Dadhwal V. K. , Kant Y. , Ali M. M.
Published: September 2012

Abstract. Atmospheric carbon dioxide (CO2) is the major greenhouse gas. We analysed the diurnal trend and seasonal variations of atmospheric Carbon Dioxide (CO2) measured at Dehradun during 2009. The measurements are taken from the Vaisala CO2 probe installed at the top of the IIRS building. A distinct diurnal cycle with seasonal variations is present in these measurements. Diurnal cycle exhibits a half sinusoidal variation with decreasing phase during sunrise to afternoon and increasing phase during afternoon to sunset. CO2 mostly remains constant with higher values during the night. The largest negative anomaly with respect to the annual mean varies between +/-20 ppmv with positive anomaly during the night time and negative anomaly during the day time. The cause of such variation could be attributed to the local ecosystem activity. During the day time the sinking of CO2 through the photosynthesis dominates its release through autotrophic and heterotrophic respiration. On the other hand, photosynthesis has been ceased during the night time and respiration only controls the night variation of CO2.There exists significant change on the diurnal cycle of CO2 in different seasons during the year. The maximum rapid decrease in CO2 concentration in early morning hours is due to photosynthetic activity during the monsoon periods (maximum in August -8ppm). During monsoon period rapid night time increase of CO2 is observed due to the enhancement of respiration. An inverse relationship exist between model simulated net ecosystem productivity and CO2 deviations on monthly basis. This diurnal and seasonal variations in situ CO2 are in confirmation with model simulated results.
Review Article: "Adaptive governance and resilience: the role of multi-stakeholder platforms in disaster risk reduction"
Authors: Djalante R.
Published: September 2012

Abstract. Disaster impacts are more frequent, deadly and costly. The social and environmental consequences are increasingly complex and intertwined. Systematic as well as innovated strategies are needed to manage the impacts. Disaster Risk Reduction (DRR) is a systematic approach to manage disaster risks while adaptive governance (AG) is suggested as an alternative approach for governing complex problems such as disasters. The author proposes that the AG can be practicalised through a mechanism of multi-stakeholder platforms (MSPs), interpreted as multiplicity of organisations at different scales of governance working towards more coordinated and integrated actions in DRR. Ten MSPs are selected at the global, regional, national and local level, focussing on the Indonesian MSPs. The literature reviews and in-depth interviews with key respondents in Indonesia show that the international and regional MSPs tend to have more human, technical and financial capacity than national and local MSPs. The author finds that most MSP roles focus on the coordination amongst multitudes of organisations. Only those MSPs that are able to generate new funding have the capacity to implement direct risk reduction activities. The development of the MSP is highly influenced by the UNISDR system operating at different levels. Particularly in Indonesia, MSP are also influenced by the operations of various UN and international organisations. Finally, the paper suggests the need for more provision of technical supports to local MSPs, more linkages with established networks in DRR and broader stakeholders involvement within the MSPs.
Limitations of a coupled regional climate model in the reproduction of the observed Arctic sea-ice retreat
Authors: Dorn W. , Dethloff K. , Rinke A.
Published: September 2012

Abstract. The effects of internal model variability on the simulation of Arctic sea-ice extent and volume have been examined with the aid of a seven-member ensemble with a coupled regional climate model for the period 1948–2008. Beyond general weaknesses related to insufficient representation of feedback processes, it is found that the model's ability to reproduce observed summer sea-ice retreat depends mainly on two factors: the correct simulation of the atmospheric circulation during the summer months and the sea-ice volume at the beginning of the melting period. Since internal model variability shows its maximum during the summer months, the ability to reproduce the observed atmospheric summer circulation is limited. In addition, the atmospheric circulation during summer also significantly affects the sea-ice volume over the years leading to a limited ability to start with reasonable sea-ice volume into the melting period. Furthermore, the sea-ice volume pathway shows notable decadal variability that varies in amplitude among the ensemble members. The scatter is particularly large in periods when the ice volume increases, indicating limited skill in reproducing high-ice years.