bluuebunny/crossref_metadata_2025 huggingface dataset:
FINDING CUBOID-BASED BUILDING MODELS IN POINT CLOUDS
Authors: Nguatem W. , Drauschke M. , Mayer H.
Published: August 2012

Abstract. In this paper, we present an automatic approach for the derivation of 3D building models of level-of-detail 1 (LOD 1) from point clouds obtained from (dense) image matching or, for comparison only, from LIDAR. Our approach makes use of the predominance of vertical structures and orthogonal intersections in architectural scenes. After robustly determining the scene's vertical direction based on the 3D points we use it as constraint for a RANSAC-based search for vertical planes in the point cloud. The planes are further analyzed to segment reliable outlines for rectangular surface within these planes, which are connected to construct cuboid-based building models. We demonstrate that our approach is robust and effective over a range of real-world input data sets with varying point density, amount of noise, and outliers.
THE RESEARCH OF LINE MATCHING ALGORITHM UNDER THE IMPROVED HOMOGRAPH MATRIX CONSTRAINT CONDITION
Authors: Wang W. , Lou A. , Wang J.
Published: August 2012

Abstract. Focusing on the mismatching problems in line matching, this paper integrates the radiation information and the geometry information of the imagery as the multi-constraint conditions, and presents an improved line matching algorithm based on the improved homograph matrix constraint condition. This algorithm firstly obtains the homologous points by feature matching, and for each line to be matched, it calculates the homograph matrix with the homologous points in the neighbourhood of this line. And then it projects the line to be matched line in target image to the search image by the homograph matrix, and determines the candidate lines according to the distance between the central points of lines and the distance between two lines; In these candidate lines, this algorithm further determines the possible homologous lines according to the similarity constraints of the line angles, the distance from the origin of image to the lines, and the overlap of lines; Finally, the epipolar constraint is adopted to find out the overlap segments between homologous lines，and the real homologous line will be determined by the gray similarity constraint. This paper adopts the unmanned aerial vehicle images and UCX digital aerial images to carry on the experiments, and verifies the validity of the algorithm in this paper.
OPTIMISATION OF FUZZY BASED SOFT CLASSIFIERS FOR REMOTE SENSING DATA
Authors: Dwivedi R. , Kumar A. , Ghosh S. K. , Roy P. S.
Published: August 2012

Abstract. Classification of satellite images are complex process and accuracy of the output is dependent on classifier parameters. This paper examines the effect of various parameters like weighted exponent "m" for FCM , PCM classifiers and weighted exponent "m" as well as fixed parameter "?" for NC without entropy based algorithm. The prime focus in this work is to select suitable parameters for classification of remotely sensed data which improves the accuracy of classification output. The uncertainty criterion has been estimated from sub-pixel confusion uncertainty matrix (SCM), based on classified and testing outputs. Therefore, these criterions are dependent on the error of the results and sensitive to error variations. So it has also been tried to estimate entropy, based on outputs generated by various classifiers like FCM, PCM and NC without entropy based classifier, hence this computed entropy is sensitive to uncertainty variations. The AWiFS and LISS-III datasets are being used for classification and testing respectively. Soft classified outputs from FCM, PCM and NC without entropy classifiers for AWiFS and LISS-III have been evaluated using SCM, overall accuracy, fuzzy kappa coefficient and entropy. The SCM and fuzzy kappa coefficients are used to major relative accuracies, while entropy is an absolute uncertainty indicator. From resultant aspect, while monitoring entropy of fraction images for different regularizing parameter values, optimum regularizing parameter has been obtained for "m" = 2.0 and "?" = 1, which gives highest accuracy from sub-pixel confusion uncertainty matrix (SCM) i.e. 96.27% and AWiFS entropy has been 0.71 using noise clustering without entropy based classifier.
3D CLASSIFICATION OF CROSSROADS FROM MULTIPLE AERIAL IMAGES USING MARKOV RANDOM FIELDS
Authors: Kosov S. , Rottensteiner F. , Heipke C. , Leitloff J. , Hinz S.
Published: August 2012

Abstract. The precise classification and reconstruction of crossroads from multiple aerial images is a challenging problem in remote sensing. We apply the Markov Random Fields (MRF) approach to this problem, a probabilistic model that can be used to consider context in classification. A simple appearance-based model is combined with a probabilistic model of the co-occurrence of class label at neighbouring image sites to distinguish up to 14 different classes that are relevant for scenes containing crossroads. The parameters of these models are learnt from training data. We use multiple overlap aerial images to derive a digital surface model (DSM) and a true orthophoto without moving cars. From the DSM and the orthophoto we derive feature vectors that are used in the classification. One of the features is a car confidence value that is supposed to support the classification when the road surface is occluded by static cars. Our approach is evaluated on a dataset of airborne photos of an urban area by a comparison of the results to reference data. Whereas the method has problems in distinguishing classes having a similar appearance, it is shown to produce promising results if a reduced set of classes is considered, yielding an overall classification accuracy of 74.8%.
SYSTEMATIC BUNDLE ADJUSTMENT OF HRSC IMAGE DATA
Authors: Bostelmann J. , Schmidt R. , Heipke C.
Published: August 2012

Abstract. The European Mars Express mission was launched in June 2003 and sent into orbit around Mars. On board the orbiter is the German High Resolution Stereo Camera (HRSC). This multi-line sensor images the Martian surface with a resolution of up to 12m per pixel in three dimensions and provides RGB and infra-red color information. The usage of the stereoscopic image information for the improvement of the observed position and attitude information via bundle adjustment is important to derive high quality 3D surface models, color orthoimages and other data products. In many cases overlapping image strips of different orbits can be used to form photogrammetric blocks, thus allowing the simultaneous adjustment of the exterior orientation data. This reduces not only local, but also regional inconsistencies in the data. With the growing number of HRSC image strips in this ongoing mission, the size and complexity of potential blocks is increasing. Therefore, a workflow has been built up for the systematic improvement of the exterior orientation using single orbit strips and regional blocks. For a successful bundle adjustment of blocks using multiple image strips a sufficient number of tie points in the overlapping area is needed. The number of tie points depends mainly on the geometric and radiometric quality of the images. This is considered by detailed analysis of the tie point accuracy and distribution. The combination of methods for image pre-processing, tie point matching, bundle adjustment and evaluation of the results in an automated workflow allows for all HRSC images a global assessment of the quality and a systematic selection of data for larger blocks.
GOOGLE MAPS FOR CROWDSOURCED EMERGENCY ROUTING
Authors: Nedkov S. , Zlatanova S.
Published: August 2012

Abstract. Gathering infrastructure data in emergency situations is challenging. The affected by a disaster areas are often large and the needed observations numerous. Spaceborne remote sensing techniques cover large areas but they are of limited use as their field of view may be blocked by clouds, smoke, buildings, highways, etc. Remote sensing products furthermore require specialists to collect and analyze the data. This contrasts the nature of the damage detection problem: almost everyone is capable of observing whether a street is usable or not. The crowd is fit for solving these challenges as its members are numerous, they are willing to help and are often in the vicinity of the disaster thereby forming a highly dispersed sensor network. This paper proposes and implements a small WebGIS application for performing shortest path calculations based on crowdsourced information about the infrastructure health. The application is built on top of Google Maps and uses its routing service to calculate the shortest distance between two locations. Impassable areas are indicated on a map by people performing in-situ observations on a mobile device, and by users on a desktop machine who consult a multitude of information sources.
LANDSAFE: LANDING SITE RISK ANALYSIS SOFTWARE FRAMEWORK
Authors: Schmidt R. , Bostelmann J. , Cornet Y. , Heipke C. , Philippe C. , Poncelet N. , de Rosa D. , Vandeloise Y.
Published: August 2012

Abstract. The European Space Agency (ESA) is planning a Lunar Lander mission in the 2018 timeframe that will demonstrate precise soft landing at the polar regions of the Moon. To ensure a safe and successful landing a careful risk analysis has to be carried out. This is comprised of identifying favorable target areas and evaluating the surface conditions in these areas. Features like craters, boulders, steep slopes, rough surfaces and shadow areas have to be identified in order to assess the risk associated to a landing site in terms of a successful touchdown and subsequent surface operation of the lander. In addition, global illumination conditions at the landing site have to be simulated and analyzed. The Landing Site Risk Analysis software framework (LandSAfe) is a system for the analysis, selection and certification of safe landing sites on the lunar surface. LandSAfe generates several data products including high resolution digital terrain models (DTMs), hazard maps, illumination maps, temperature maps and surface reflectance maps which assist the user in evaluating potential landing site candidates. This paper presents the LandSAfe system and describes the methods and products of the different modules. For one candidate landing site on the rim of Shackleton crater at the south pole of the Moon a high resolution DTM is showcased.
ASSESSMENT OF THE HOMOGENEITY OF VOLUNTEERED GEOGRAPHIC INFORMATION IN SOUTH AFRICA
Authors: Siebritz L. , Sithole G. , Zlatanova S.
Published: August 2012

Abstract. The potential for volunteer groups to contribute geographic data to National Mapping Agencies has been widely recognised. Several investigations have been done to determine the geometric accuracy of this data for the purposes of national mapping. Beyond accuracy, from a production perspective National Mapping Agencies will also be interested in the sufficiency and uniformity of the data. This paper presents an investigation of whether presently geographic data generated by volunteers is uniform across a country and whether the rate of production of data is consistent. For the purpose of the test, changes in data of South Africa from OpenStreetMap are analysed for the period 2006 to 2011. Here only point and line data are considered. The results generally show that the rate at which data is generated varies in space and time. The results also confirm that volunteers emphasise on the capture of certain information and that the capture doesn’t average out as might be expected. The results also showed that social events, such as a World Cup, also have the effect of spurring the generation of volunteer geographic data. The implication of these results for National Mapping Agencies is that they cannot treat volunteer geographic information as being of a uniform standard. How National Mapping Agencies respond to this will have to be the subject of other investigations.
AUTOMATED FEATURE BASED TLS DATA REGISTRATION FOR 3D BUILDING MODELING
Authors: Kitamura K. , Kochi N. , Kaneko S.
Published: August 2012

Abstract. In this paper we present a novel method for the registration of point cloud data obtained using terrestrial laser scanner (TLS). The final goal of our investigation is the automated reconstruction of CAD drawings and the 3D modeling of objects surveyed by TLS. Because objects are scanned from multiple positions, individual point cloud need to be registered to the same coordinate system. We propose in this paper an automated feature based registration procedure. Our proposed method does not require the definition of initial values or the placement of targets and is robust against noise and background elements. A feature extraction procedure is performed for each point cloud as pre-processing. The registration of the point clouds from different viewpoints is then performed by utilizing the extracted features. The feature extraction method which we had developed previously (Kitamura, 2010) is used: planes and edges are extracted from the point cloud. By utilizing these features, the amount of information to process is reduced and the efficiency of the whole registration procedure is increased. In this paper, we describe the proposed algorithm and, in order to demonstrate its effectiveness, we show the results obtained by using real data.
A NOVEL IMAGE ACQUISITION AND PROCESSING PROCEDURE FOR FAST TUNNEL DSM PRODUCTION
Authors: Roncella R. , Umili G. , Forlani G.
Published: August 2012

Abstract. In mining operations the evaluation of the stability condition of the excavated front are critic to ensure a safe and correct planning of the subsequent activities. The procedure currently used to this aim has some shortcomings: safety for the geologist, completeness of data collection and objective documentation of the results. In the last decade it has been shown that the geostructural parameters necessary to the stability analysis can be derived from high resolution digital surface models (DSM) of rock faces. With the objective to overcome the limitation of the traditional survey and to minimize data capture times, so reducing delays on mining site operations, a photogrammetric system to generate high resolution DSM of tunnels has been realized. A fast, effective and complete data capture method has been developed and the orientation and restitution phases have been largely automated. The survey operations take no more than required to the traditional ones; no additional topographic measurements other than those available are required. To make the data processing fast and economic our Structure from Motion procedure has been slightly modified to adapt to the peculiar block geometry while, the DSM of the tunnel is created using automatic image correlation techniques. The geomechanical data are sampled on the DSM, by using the acquired images in a GUI and a segmentation procedure to select discontinuity planes. To allow an easier and faster identification of relevant features of the surface of the tunnel, using again an automatic procedure, an orthophoto of the tunnel is produced. A case study where a tunnel section of ca. 130 m has been surveyed is presented.
ACCURACY ASPECTS OF UTILIZING RAW IMAGERY IN PHOTOGRAMMETRIC MEASUREMENT
Authors: Stamatopoulos C. , Fraser C. S. , Cronk S.
Published: August 2012

Abstract. Implicit in the projective transformation between object and image space in photogrammetry is the requirement that measured coordinates of points in the digital images accurately represent true values within the image coordinate system. This means that the integrity of image point positions has to be retained throughout the in-camera image preprocessing stage. However, the process of image formation and formatting for storage can impact upon image point position and it is imperative for subsequent photogrammetric measurement that image perturbations due to both sensor non-linearities and digital image file creation be fully described, modelled and mitigated to the maximum extent possible. Given that the integrity of image geometry is such an important factor in the optimisation of measurement accuracy in close-range photogrammetry, investigations into digital image formation are warranted. This paper describes such an investigation and it reports the development of a preprocessing approach for RAW imagery than can yield significant photogrammetric accuracy improvements over those obtained with JPEG imagery.
DETERMINATION OF THE DEGREE OF GRAVEL AGGREGATE-BITUMENCOVERAGE BY MULTI-DIRECTIONAL REFLECTANCE MEASUREMENTS
Authors: Mulsow C.
Published: August 2012

Abstract. The paper describes the determination of the percentage area of bitumen on partly covered aggregate. This task is a typical issue in material testing in road construction. The asphalt components bitumen and aggregate are subjected to defined mechanical stress in the presence of water in order to test the affine properties of the components. The degree to which the bitumen separates from the aggregate surface serves as an indicator for the quality of the affinity. Until now, examiners have been judging the coverage degree of samples by visual rating. Several research projects attempted to replace the error-prone subjective assessment by automatic procedures. These procedures analyse the different chromaticities of aggregate and bitumen in RGB images. However, these approaches as a whole are not reliable enough because of the rather specific requirements that are made on the environmental conditions when the picture is taken (illumination, exclusion of extraneous light) and also on the lab assistant (manual definition of training areas, management of camera and illumination parameters). Moreover, the analysis is not suitable for all types of rock because of the necessary difference in colour between bitumen and aggregate (e.g. dark rock samples). Contrary to previous approaches, the new multi-directional reflectance measurements use the different surface characteristics of bitumen and aggregate instead of the chromaticities as separation criteria. These differences are made visible by directional lighting with a laser. The diffuse reflection from the aggregate surface and the directional reflection from the optically smoother bitumen produce definitely distinguishable brightnesses in the image. Thus the colour of the material is of no significance. The approach was used in a procedure and assessed. The paper presents the method itself, approaches for the elimination of reflections and first results. Moreover, the measuring principle is compared with existing procedures and benefits and drawbacks are outlined.
AUTOMATED LOW-COST PHOTOGRAMMETRY FOR FLEXIBLE STRUCTURE MONITORING
Authors: Wang C. H. , Mills J. P. , Miller P. E.
Published: August 2012

Abstract. Structural monitoring requires instruments which can provide high precision and accuracy, reliable measurements at good temporal resolution and rapid processing speeds. Long-term campaigns and flexible structures are regarded as two of the most challenging subjects in monitoring engineering structures. Long-term monitoring in civil engineering is generally considered to be labourintensive and financially expensive and it can take significant effort to arrange the necessary human resources, transportation and equipment maintenance. When dealing with flexible structure monitoring, it is of paramount importance that any monitoring equipment used is able to carry out rapid sampling. Low cost, automated, photogrammetric techniques therefore have the potential to become routinely viable for monitoring non-rigid structures. This research aims to provide a photogrammetric solution for long-term flexible structural monitoring purposes. The automated approach was achieved using low-cost imaging devices (mobile phones) to replace traditional image acquisition stations and substantially reduce the equipment costs. A self-programmed software package was developed to deal with the hardware-software integration and system operation. In order to evaluate the performance of this low-cost monitoring system, a shaking table experiment was undertaken. Different network configurations and target sizes were used to determine the best configuration. A large quantity of image data was captured by four DSLR cameras and four mobile phone cameras respectively. These image data were processed using photogrammetric techniques to calculate the final results for the system evaluation.
MULTIPLATFORM APPROACH TO MOBILE LASER SCANNING
Authors: Kukko A. , Kaartinen H. , Hyyppä J. , Chen Y.
Published: August 2012

Abstract. Mobile laser scanning is an emerging technology for capturing three-dimensional information from the surrounding objects. With state of the art sensors the achieved point cloud could capture fine details of the surroundings with good accuracy and effectiveness. Many of the applications deal with the civil engineering purposes in urban areas for traffic and city planning and modelling. In this article we present multiplatform mobile laser scanning solutions for mapping applications that require mobility in various terrains and river environments but yet produce high density point clouds with good reliability and accuracy. The ROAMER mobile laser scanning system was deployed in multitude of tasks from urban areas to climate research. The paper also introduces a completely new backpack Akhka platform for mobile lidar mapping of areas where wheeled vehicles cannot operate. The sensor set is the same in all of the approaches, but the carrying vessel was selected according to the application. This was possible thanks to a relatively light and compact yet simple design of the system. ROAMER system is one of the few high-end MLS systems that are easily adaptable to various platforms. In addition to technical description of the system we discuss the practical performance of the solutions through various applications in the fields of urban mapping, fluvial geomorphology, snow cover characterization and climate change monitoring.
PILOT STUDIES WITH A PHOTOGRAMMETRIC GLACIER LAKE OUTBURST FLOOD EARLY WARNING SYSTEM
Authors: Maas H. G. , Mulsow C. , Wendt A. , Casassa G.
Published: August 2012

Abstract. Glacier Lake Outburst Floods (GLOFs) depict an environmental risk with an increasing damage potential in many regions of the world. GLOFs are often caused by glacier margin lakes, which suddenly find a drainage path underneath the bottom of a glacier, which is destabilized and retreating as a consequence of local or global climate changes. In a typical GLOF event, a glacier margin lake may drain completely in 24 hours, causing a large flood wave in the area downstream the glacier. The paper documents some recent GLOF events in the Northern Patagonian Icefield (Chile) and presents a terrestrial photogrammetric glacier margin lake monitoring system. The system is based on a camera taking images at regular time intervals. In these images, variations of the water level can be detected by tracking the water-land interface at pre-defined image spots. Due to the drainage mechanism, which is characterized by progressive erosion and melting at the bottom of the glacier, GLOFs are indicated by a progressive water level drop in the lake. Water level changes may be detected with subpixel accuracy by image sequence processing methods. If a 3D model of the lake bottom topography (or at least one height profile through the lake) exists, water level changes in monoscopic image sequences may be transformed into volume loss. The basic idea herein is the intersection of a terrain profile with a water level detected in the image and projected into object space. The camera orientation is determined through a GPS-supported photogrammetric network. Camera orientation changes, which may for instance be induced by wind, can be compensated by tracking some fiducial marks in the image. The system has been used in a pilot study at two glacier margin lakes in the Northern Patagonian Icefield. These lakes have a depth of about 80 - 100 meters. The larger one has a length of 5 km and a maximum volume of about 200,000,000 cubic meters. During the pilot study, several GLOF events could be recorded and processed. Water level changes can be determined at decimeter level precision. The results prove the feasibility of the concept, which has to be completed by a data telemetry and alarm system.
FAST OCCLUSION AND SHADOW DETECTION FOR HIGH RESOLUTION REMOTE SENSING IMAGE COMBINED WITH LIDAR POINT CLOUD
Authors: Hu X. , Li X.
Published: August 2012

Abstract. The orthophoto is an important component of GIS database and has been applied in many fields. But occlusion and shadow causes the loss of feature information which has a great effect on the quality of images. One of the critical steps in true orthophoto generation is the detection of occlusion and shadow. Nowadays LiDAR can obtain the digital surface model (DSM) directly. Combined with this technology, image occlusion and shadow can be detected automatically. In this paper, the Z-Buffer is applied for occlusion detection. The shadow detection can be regarded as a same problem with occlusion detection considering the angle between the sun and the camera. However, the Z-Buffer algorithm is computationally expensive. And the volume of scanned data and remote sensing images is very large. Efficient algorithm is another challenge. Modern graphics processing unit (GPU) is much more powerful than central processing unit (CPU). We introduce this technology to speed up the Z-Buffer algorithm and get 7 times increase in speed compared with CPU. The results of experiments demonstrate that Z-Buffer algorithm plays well in occlusion and shadow detection combined with high density of point cloud and GPU can speed up the computation significantly.
LARGE AREA LAND COVER CLASSIFICATION WITH LANDSAT ETM+ IMAGES BASED ON DECISION TREE
Authors: Zhai L. , Sun J. , Sang H. , Yang G. , Jia Y.
Published: August 2012

Abstract. Traditional land classification techniques for large areas that use LANDSAT TM imagery are typically limited to the fixed spatial resolution of the sensors. For modeling habitat characteristics is often difficult when a study area is large and diverse and complete sampling of environmental variables is unrealistic. We also did some researches on this field, in this paper we firstly introduced the decision tree classification based on C5.0, and then introduced the classification workflow. The study results were compared with the Maximum Likelihood Classification result. Victoria of Australia was as the study area, the LANDSAT ETM+ images were used to classify. Experiments show that the decision tree classification method based on C5.0 is better.
ASSESSING THE FEASIBILITY OF UAV-BASED LIDAR FOR HIGH RESOLUTION FOREST CHANGE DETECTION
Authors: Wallace L. O. , Lucieer A. , Watson C. S.
Published: August 2012

Abstract. Airborne LiDAR data has become an important tool for both the scientific and industry based investigation of forest structure. The uses of discrete return observations have now reached a maturity level such that the operational use of this data is becoming increasingly common. However, due to the cost of data collection, temporal studies into forest change are often not feasible or completed at infrequent and at uneven intervals. To achieve high resolution temporal LiDAR surveys, this study has developed a micro-Unmanned Aerial Vehicle (UAV) equipped with a discrete return 4-layer LiDAR device and miniaturised positioning sensors. This UAV has been designed to be low-cost and to achieve maximum flying time. In order to achieve these objectives and overcome the accuracy restrictions presented by miniaturised sensors a novel processing strategy based on a Kalman smoother algorithm has been developed. This strategy includes the use of the structure from motion algorithm in estimating camera orientation, which is then used to restrain IMU drift. The feasibility of such a platform for monitoring forest change is shown by demonstrating that the pointing accuracy of this UAV LiDAR device is within the accuracy requirements set out by the Australian Intergovernmental Committee on Surveying and Mapping (ICSM) standards.
OPTIMIZATION OF DECISION-MAKING FOR SPATIAL SAMPLING IN THE NORTH CHINA PLAIN, BASED ON REMOTE-SENSING A PRIORI KNOWLEDGE
Authors: Feng J. , Bai L. , Liu S. , Su X. , Hu H.
Published: August 2012

Abstract. In this paper, the MODIS remote sensing data, featured with low-cost, high-timely and moderate/low spatial resolutions, in the North China Plain (NCP) as a study region were firstly used to carry out mixed-pixel spectral decomposition to extract an useful regionalized indicator parameter (RIP) (i.e., an available ratio, that is, fraction/percentage, of winter wheat planting area in each pixel as a regionalized indicator variable (RIV) of spatial sampling) from the initial selected indicators. Then, the RIV values were spatially analyzed, and the spatial structure characteristics (i.e., spatial correlation and variation) of the NCP were achieved, which were further processed to obtain the scalefitting, valid a priori knowledge or information of spatial sampling. Subsequently, founded upon an idea of rationally integrating probability-based and model-based sampling techniques and effectively utilizing the obtained a priori knowledge or information, the spatial sampling models and design schemes and their optimization and optimal selection were developed, as is a scientific basis of improving and optimizing the existing spatial sampling schemes of large-scale cropland remote sensing monitoring. Additionally, by the adaptive analysis and decision strategy the optimal local spatial prediction and gridded system of extrapolation results were able to excellently implement an adaptive report pattern of spatial sampling in accordance with report-covering units in order to satisfy the actual needs of sampling surveys.
BATHYMETRIC EXTRACTION USING WORLDVIEW-2 HIGH RESOLUTION IMAGES
Authors: Deidda M. , Sanna G.
Published: August 2012

Abstract. The fundamental principle underlying the methods used to extract bathymetric information from remote-sensed imagery is that different wavelengths of the solar light penetrate the water body to different depths. In order to extract bathymetric values from multispectral satellite imagery we implemented the Jupp method (Jupp, 1988), in IDL language and integrated it in the ENVI menu structure. In this experiment we apply this method to two images of the Poetto beach in Cagliari (Sardinia, Italy) acquired from the new-generation WorldView-2 sensor. Launched in October 2009, the WorldView-2 sensor provides, among others, one (named Coastal) that was designed specifically for this kind of analysis; we chose to use the Coastal band in place of the Blue one when applying the model. The images (a stereoscopic pair) were acquired on June 17, 2011. The 5419 scene was pre-processed in order to separate the sea bottom classes. This class was then georeferenced to overlap on the 5318 scene. A traditional bathymetric survey was performed, up to 1,50 m, planned and carried out in order to calibrate the model. For each scene, 10 calibration areas were selected, and for each of them a digital model of the sea bottom was generated. Precision and accuracy of the method were evaluated by analyzing the results extracted from the stereo-pairs and by examining the correlation between the surveyed depth values and the calculated ones, between the different models calculated from the same scene using different calibration areas, and between the models obtained from the two images.
WATER BODY EXTRACTION FROM MULTI SPECTRAL IMAGE BY SPECTRAL PATTERN ANALYSIS
Authors: Nguyen D. D.
Published: August 2012

Abstract. Water is one of the vital components of the Earth environment which needs to be frequently monitored. Satellite multispectral remote sensing image has been used over decades for water body extraction. Methodology of water body extraction can be summarized to three groups: feature extraction, supervised and unsupervised classification and data fusion. These methods, however, are of pure mathematical and statistical approach and little of them explore essential characteristics of multispectral image which is based on ground object radiance absorption behaviour in each sensing spectral bands. The spectral absorption characteristics of water body in visible and infrared bands differ very much from the other ground objects. They depend only on the used spectral bands and can be considered as invariant and sensor independent. In this paper the author proposed an application of spectral pattern analysis for water body extraction using spectral bands green, red, near infrared NIR and short wave infrared SWIR. The proposed algorithm has been used for water body extraction by Spot 5 and Landsat 5 TM images. Ground truth validation was carried out in Hanoi City. The advantage of this algorithm does not base on water body extraction only but it allows to asses also water quality. Different level of turbidity and organic matter contents could be classified by using additional index.
EXPLORING CLIMATE CHANGE EFFECTS ON WATERSHED SEDIMENT YIELD AND LAND COVER-BASED MITIGATION MEASURES USING SWAT MODEL, RS AND GIS: CASE OF CAGAYAN RIVER BASIN, PHILIPPINES
Authors: Principe J. A.
Published: August 2012

Abstract. The impact of climate change in the Philippines was examined in the country's largest basin–the Cagayan River Basin–by predicting its sediment yield for a long period of time. This was done by integrating the Soil and Water Assessment Tool (SWAT) model, Remote Sensing (RS) and Geographic Information System (GIS). A set of Landsat imageries were processed to include an atmospheric correction and a filling procedure for cloud and cloud-shadow infested pixels was used to maximize each downloaded scene for a subsequent land cover classification using Maximum Likelihood classifier. The Shuttle Radar Topography Mission (SRTM)-DEM was used for the digital elevation model (DEM) requirement of the model while ArcGIS™ provided the platform for the ArcSWAT extension, for storing data and displaying spatial data. The impact of climate change was assessed by varying air surface temperature and amount of precipitation as predicted in the Intergovernmental Panel on Climate Change (IPCC) scenarios. A Nash-Sutcliff efficiency (NSE) > 0.4 and coefficient of determination (R2) > 0.5 for both the calibration and validation of the model showed that SWAT model can realistically simulate the hydrological processes in the study area. The model was then utilized for land cover change and climate change analyses and their influence on sediment yield. Results showed a significant relationship exists among the changes in the climate regime, land cover distributions and sediment yield. Finally, the study suggested land cover distribution that can potentially mitigate the serious negative effects of climate change to a regional watershed's sediment yield.
IDENTIFICATION OF GEOMORPHIC SIGNATURES OF NEOTECTONIC ACTIVITY USING DEM IN THE PRECAMBRIAN TERRAIN OF WESTERN GHATS, INDIA
Authors: Jayappa K. S. , Markose V. J. , Nagaraju M.
Published: August 2012

Abstract. To assess the relative tectonic activity classes, five geomorphic indices such as stream-gradient index (SL), drainage basin asymmetry (Af), hypsometric integral (Hi), valley floor width – valley height ratio (Vf) and drainage basin shape (Bs) of ninety-four sub-basins of Valapattanam river basin have been analysed by applying the standard formulae. Relative tectonic activity classes (Iat) obtained by the average (S/n) of different classes of geomorphic indices have been classified into three groups. Group I shows high tectonic activity with values of S/n < 2; group II shows moderate tectonic activity with S/n > 2 to < 2.5; and group III shows low tectonic activity with values of S/n ≥ 2.5. Field evidences such as deep valleys, sudden changes in the river course and waterfalls at fault planes clearly agree with the values and classes of tectonic geomorphic indices.
DO ADDITIONAL BANDS (COASTAL, NIR-2, RED-EDGE AND YELLOW) IN WORLDVIEW-2 MULTISPECTRAL IMAGERY IMPROVE DISCRIMINATION OF AN INVASIVE TUSSOCK, BUFFEL GRASS (CENCHRUS CILIARIS)?
Authors: Marshall V. , Lewis M. , Ostendorf B.
Published: August 2012

Abstract. Our goals is to determine if Worldview-2 8-band multispectral imagery can be used to discriminate an invasive grass species namely, Buffel grass (Cenchrus ciliaris) in the subtropical arid parts of central Australia and whether it offers a tangible improvement on 4-band (visible and near infra red) multispectral imagery. A Worldview-2 scene was acquired for a 10*10km area just west of Alice Springs in central Australia following heavy rains of early Summer. Mixture Tuned Matched Filtering was used to classify the image. Target and background spectra were selected in the field and extracted from the image. Linear discriminate analysis (LDA) was used to examine the spectral separability of each group of the target/ background spectra. The importance of the additional spectral bands on the image classification was assessed by running LDA for both 8 and 4 bands (red, green, blue and NIR). LDA did not indicate improved separability between groups when additional spectral bands were applied. Preliminary classification results indicate that Buffel grass (Cenchrus ciliaris) is detected with an omission error 44%, commission error of 11.8% and overall accuracy of 59.5%. We were surprised that the additional spectral bands did not improve spectral separability and in part attribute this to the high degree of variance we observed within groups of spectra, which was particularly observable in the NIR2 and Yellow bands. The analyses may be significantly improved by acquiring imagery following the first big rains at the end of the dry season. At this time, phonological differences between our focal species and the surrounding native vegetation should be maximised. We suspect that Worldview-2 will offer even greater potential for the discrimination of Buffel grass under these conditions, being able to fully utilise the yellow-band in particular.
LOW-COST OPTICAL CAMERA SYSTEM FOR DISASTER MONITORING
Authors: Kurz F. , Meynberg O. , Rosenbaum D. , Türmer S. , Reinartz P. , Schroeder M.
Published: August 2012

Abstract. Real-time monitoring of natural disasters, mass events, and large accidents with airborne optical sensors is an ongoing topic in research and development. Airborne monitoring is used as a complemental data source with the advantage of flexible data acquisition and higher spatial resolution compared to optical satellite data. In cases of disasters or mass events, optical high resolution image data received directly after acquisition are highly welcomed by security related organizations like police and rescue forces. Low-cost optical camera systems are suitable for real-time applications as the accuracy requirements can be lowered in return for faster processing times. In this paper, the performance of low-cost camera systems for real-time mapping applications is exemplarily evaluated based on already existing sensor systems operated at German Aerospace Center (DLR). Focus lies next to the geometrical and radiometric performance on the real time processing chain which includes image processors, thematic processors for automatic traffic extraction and automatic person tracking, data downlink to the ground station, and further processing and distribution on the ground. Finally, a concept for a national airborne rapid mapping service based on the low-cost hardware is proposed.
DEVELOPMENT OF PHOTOGRAMMETRY SYSTEM FOR GRASPING FOREST RESOURCES INFORMATION
Authors: Uramoto Y. , Zhu L. , Tachibana K. , Shimamura H. , Ogaya N.
Published: August 2012

Abstract. We have developed a digital photogrammetry system specialized for grasping the forest resources information. In this system, 3D view of aerial photos can be displayed on a PC monitor or a projector. Unlike orthophotos, the 3D display has depth information in it. Hence, the tree canopy size, tree decay situation, etc. can be visualized with more perfection. Moreover, tree heights, forest types and their regions, etc. can also be calculated by this system. Vectorization and segmentation of area, as per forest type, etc., is also possible. In this system, the basic timber volume can be estimated by using aerial photos. Therefore, it reduces the field survey cost significantly. For the efficient use of this kind of system, a system should be used even by non experts with a very basic operational technique. Hence, we have added a series of extra functions in our system and asked a non expert to perform the analysis. A non photogrammetrists was asked to calculate the timber volume and tree height by using this system. With the very limited instructions from an expert, and in a short period of time, the person was able to use this system quite efficiently and got a good
GULLIES, GOOGLE EARTH AND THE GREAT BARRIER REEF: A REMOTE SENSING METHODOLOGY FOR MAPPING GULLIES OVER EXTENSIVE AREAS
Authors: Gilad U. , Denham R. , Tindall D.
Published: August 2012

Abstract. Recent work suggests that gully erosion is the main contributor of sediments to the Great Barrier Reef, Australia. The objectives of this study were to identify the location of gullies as well as the landscape characteristics associated with gully presence in the Burdekin Catchment. Data were collected by random sampling using Google Earth. A spatial-statistical analysis allowed the exclusion of areas where gullies were less likely to be present. The remaining gully sensitive areas were then manually mapped by using Google Earth, assisting in the creation of a predictive map. A semi-quantitative gully presence map was also created by visually inspecting imagery at 5 km × 5 km grid cell scale. Results show a strong relationship between gully presence and drainage features, low tree cover and low slopes. The resulting predictive map has correctly allocated more than 90% of gullies within less than 20% of the Burdekin's area, yet uncertainties still remain. The manually derived mapping product comprises the most comprehensive gully data available for the Burdekin, while the high-resolution predictive map and the 5 km × 5 km grid map will allow better targeting of gullied areas in later stages of this research. This study also provides a methodology that can be applied to mapping gullies over extensive areas. It demonstrates how Google Earth could be used as a reliable platform for mapping gullies and discusses the limitations in the use of remotely sensed data for gully mapping and modelling.
Fabrication and Development of Pectin Microsphere of Metformin Hydrochloride
Authors: Banerjee Pritam , Deb Jyotirmoy , Roy Amitava , Ghosh Amitava , Chakraborty Prithviraj
Published: August 2012

Purpose. The objective of the proposed work is to evaluate the efficacy of Pectins to qualify them as polymers for designing an oral microsphere for the delivery of selected oral antidiabetic drug-like metformin hydrochloride. Methods. Different Microspheres formulations were prepared by the water in oil (w\o) emulsion solvent evaporation technique and subsequently evaluated for its different physical parameters as well as its in vitro and in vivo drug release study. Results. The formulations F2 (98.42) and F3 (98.03) showed a constant and high release in the dissolution profile, so among these two formulations, F2 was taken for development study, due to the better result shown over in other evaluation parameters. From the HPLC determinations after in vivo study, it had been found that the test samples and the standard sample had not shown any significant fluctuation in relation to their retention time. Conclusion. From in vitro and in  vivo results, it may be concluded that drug-loaded pectin microspheres in 1 : 1 ratio are a suitable delivery system for metformin hydrochloride and may be used for effective management of NIDDM. From this experiment, it could be concluded that as a natural polymer, pectin has potentiality in novel drug delivery system.
Simultaneous Estimation of Metoprolol Succinate and Olmesartan Medoxomil in Pharmaceutical Formulation by Thin-Layer Chromatographic-Densitometric Method
Authors: Baldania Sunil L. , Parmar Ankit B. , Bhatt Kashyap K. , Shah Dimal A. , Chhalotiya Usmangani K.
Published: August 2012

A new, simple, accurate, and precise high-performance thin-layer chromatographic (HPTLC) method is described for simultaneous analysis of metoprolol succinate and olmesartan medoxomil in pharmaceutical formulations. The separations were achieved on prepared TLC plates precoated with silica gel G 60 F254 and the plates were developed with methanol-ethyl acetate-toluene-glacial acetic acid 2.5 : 3 : 4.5 : 0.3%v/v/vas mobile phase. Detection and evaluation of chromatograms were performed densitometrically at 224 nm. The retention factor of metoprolol succinate and olmesartan medoxomil was 0.25 and 0.70, respectively. The linear range was 1000–2250 ηg per spot for metoprolol succinate and 800–1800 ηg per spot for olmesartan medoxomil and the correlation coefficients (r) were 0.993 and 0.999, respectively. The method was validated for linearity and range, specificity, precision, accuracy, and robustness, and the results were found to be within the acceptance criteria. The method was successfully applied to the analysis of drugs in their capsule dosage form.
Key Management Schemes for Multilayer and Multiple Simultaneous Secure Group Communication
Authors: Aparna R. , Amberker B. B.
Published: August 2012

Many emerging applications are based on group communication model and many group communications like multimedia distribution and military applications require a security infrastructure that provides multiple levels of access control for group members. The group members are divided into a number of subgroups and placed at different privilege levels based on certain criteria. A member at higher level must be capable of accessing communication in its own level as well as its descendant lower levels but not vice versa. In this paper we propose a key management scheme for this multilayer group communication. We achieve substantial reduction in storage and encryption cost compared to the scheme proposed by Dexter et al. We also address periodic group rekeying. Applications like scientific discussion and project management may lead to a scenario in which it is necessary to set up multiple secure groups simultaneously, and few members may be part of several secure groups. Managing group keys for simultaneous secure groups is critical. In this paper we propose a novel key management scheme for multiple simultaneous groups.
What Is the Place of Intersphincteric Resection When Operating on Low Rectal Cancer?
Authors: Nagayama Satoshi , Al-Kubati Waheeb , Sakai Yoshiharu
Published: August 2012

Operating on low rectal cancer by performing an intersphincteric resection (ISR) with coloanal anastomosis has been adopted as an alternative to abdominoperineal excision (APE) following Schiessel et al. report in 1994, as it preserves the sphincter and avoids the need for a permanent stoma. We undertook a review of the recent literature specifically focusing on long-term oncologic and functional outcomes of ISR to evaluate whether this operation is a valid alternative to an APE. In conclusion, younger patients with T1 or T2 rectal cancers who require no preoperative therapy are ideal candidates for ISR, given that preoperative chemoradiotherapy may cause long-term severe anal dysfunction after ISR.
Cochlear Implant Speech Processing Using Wavelet Transform
Authors: Mehrzad M. , Abolhassani M. D. , Jafari A. H. , Alirezaie J. , Sangargir M.
Published: August 2012

We present a method for coding speech signals for the simulation of a cochlear implant. The method is based on a wavelet packet decomposition strategy. We used wavelet packet db4 for 7 levels, generated a series of channels with bandwidths exactly the same as nucleus device, and applied an input stimulus to each channel. The processed signal was then reconstructed and compared to the original signal, which preserved the contents to a high percentage. Finally, performance of the wavelet packet decomposition in terms of computational complexity was compared to other commonly used strategies in cochlear implants. The results showed the power of this method in processing of the input signal for implant users with less complexity than other methods, while maintaining the contents of the input signal to a very good extent.