bluuebunny/crossref_metadata_2025 huggingface dataset:
Detection and Compensation of Band-to-band Registration Error for Multi-spectral Imagery Caused By Satellite Jitter
Authors: Zhu Y. , Wang M. , Zhu Q. , Pan J.
Published: November 2014

Abstract. Satellite jitter has become a more and more important factor which affects the quality of imagery products with development of the high resolution satellite. This paper focused on analyzing the impact on multi-spectral image caused by satellite jitter and proposed a jitter detection and compensation method to improve the band-to-band registration efficiently when jitter exists without observation by attitude sensor. Firstly, the design of multi-spectral camera and the mainstream band-to-band registration method is introduced to explain factors influencing the registration accuracy. As one of factors, satellite jitter is an unexpected satellite movement and do have impact on registration on both across and along track but easy to be ignored for the lack of high frequency and accuracy attitude data. So next the jitter detection and compensation method is proposed, in which there are six main steps to achieve the analysis of registration accuracy with and without jitter and improvement of registration accuracy after compensation when the jitter cannot be ignored. Finally, three sets of multi-spectral images of ZY-3 were used to verify the proposed method. As a result, the error caused by satellite jitter was suppressed efficiently from 0.2pixels to 0.02pixels and registration accuracy (RMSE) was improved from 0.32 pixels to 0.11 pixels by the proposed method. The results indicate that the proposed method can detect and compensate the distortion of multi-spectral image caused by satellite jitter accurately and efficiently.
Motion Vector Field Estimation Using Brightness Constancy Assumption and Epipolar Geometry Constraint
Authors: Hosseinyalamdary S. , Yilmaz A.
Published: November 2014

Abstract. In most Photogrammetry and computer vision tasks, finding the corresponding points among images is required. Among many, the Lucas-Kanade optical flow estimation has been employed for tracking interest points as well as motion vector field estimation. This paper uses the IMU measurements to reconstruct the epipolar geometry and it integrates the epipolar geometry constraint with the brightness constancy assumption in the Lucas-Kanade method. The proposed method has been tested using the KITTI dataset. The results show the improvement in motion vector field estimation in comparison to the Lucas-Kanade optical flow estimation. The same approach has been used in the KLT tracker and it has been shown that using epipolar geometry constraint can improve the KLT tracker. It is recommended that the epipolar geometry constraint is used in advanced variational optical flow estimation methods.
Calibration of multi-camera photogrammetric systems
Authors: Detchev I. , Mazaheri M. , Rondeel S. , Habib A.
Published: November 2014

Abstract. Due to the low-cost and off-the-shelf availability of consumer grade cameras, multi-camera photogrammetric systems have become a popular means for 3D reconstruction. These systems can be used in a variety of applications such as infrastructure monitoring, cultural heritage documentation, biomedicine, mobile mapping, as-built architectural surveys, etc. In order to ensure that the required precision is met, a system calibration must be performed prior to the data collection campaign. This system calibration should be performed as efficiently as possible, because it may need to be completed many times. Multi-camera system calibration involves the estimation of the interior orientation parameters of each involved camera and the estimation of the relative orientation parameters among the cameras. This paper first reviews a method for multi-camera system calibration with built-in relative orientation constraints. A system stability analysis algorithm is then presented which can be used to assess different system calibration outcomes. The paper explores the required calibration configuration for a specific system in two situations: major calibration (when both the interior orientation parameters and relative orientation parameters are estimated), and minor calibration (when the interior orientation parameters are known a-priori and only the relative orientation parameters are estimated). In both situations, system calibration results are compared using the system stability analysis methodology.
Integrated Data Processing Methodology for Airborne Repeat-pass Differential SAR Interferometry
Authors: Dou C. , Guo H. , Han C. , Yue X. , Zhao Y.
Published: November 2014

Abstract. Short temporal baseline and multiple ground deformation information can be derived from the airborne differential synthetic aperture radar Interforemetry (D-InSAR). However, affected by the turbulence of the air, the aircraft would deviate from the designed flight path with high frequent vibrations and changes both in the flight trajectory and attitude. Restricted by the accuracy of the position and orientation system (POS), these high frequent deviations can not be accurately reported, which would pose great challenges in motion compensation and interferometric process. Thus, these challenges constrain its wider applications. The objective of this paper is to investigate the accurate estimation and compensation of the residual motion errors in the airborne SAR imagery and time-varying baseline errors between the diffirent data acquirations, furthermore, to explore the integration data processing theory for the airborne D-InSAR system, and thus help to accomplish the correct derivation of the ground deformation by using the airborne D-InSAR measurements.
Exploration of Genetic Programming Optimal Parameters for Feature Extraction from Remote Sensed Imagery
Authors: Gao P. , Shetty S. , Momm H. G.
Published: November 2014

Abstract. Evolutionary computation is used for improved information extraction from high-resolution satellite imagery. The utilization of evolutionary computation is based on stochastic selection of input parameters often defined in a trial-and-error approach. However, exploration of optimal input parameters can yield improved candidate solutions while requiring reduced computation resources. In this study, the design and implementation of a system that investigates the optimal input parameters was researched in the problem of feature extraction from remotely sensed imagery. The two primary assessment criteria were the highest fitness value and the overall computational time. The parameters explored include the population size and the percentage and order of mutation and crossover. The proposed system has two major subsystems; (i) data preparation: the generation of random candidate solutions; and (ii) data processing: evolutionary process based on genetic programming, which is used to spectrally distinguish the features of interest from the remaining image background of remote sensed imagery. The results demonstrate that the optimal generation number is around 1500, the optimal percentage of mutation and crossover ranges from 35% to 40% and 5% to 0%, respectively. Based on our findings the sequence that yielded better results was mutation over crossover. These findings are conducive to improving the efficacy of utilizing genetic programming for feature extraction from remotely sensed imagery.
Multisensensor Multitemporal Data Fusion Using Wavelet Transform
Authors: Ghannam S. , Awadallah M. , Abbott A. L. , Wynne R. H.
Published: November 2014

Abstract. Interest in data fusion, for remote-sensing applications, continues to grow due to the increasing importance of obtaining data in high resolution both spatially and temporally. Applications that will benefit from data fusion include ecosystem disturbance and recovery assessment, ecological forecasting, and others. This paper introduces a novel spatiotemporal fusion approach, the wavelet-based Spatiotemporal Adaptive Data Fusion Model (WSAD-FM). This new technique is motivated by the popular STARFM tool, which utilizes lower-resolution MODIS imagery to supplement Landsat scenes using a linear model. The novelty of WSAD-FM is twofold. First, unlike STARFM, this technique does not predict an entire new image in one linear step, but instead decomposes input images into separate "approximation" and "detail" parts. The different portions are fed into a prediction model that limits the effects of linear interpolation among images. Low-spatial-frequency components are predicted by a weighted mixture of MODIS images and low-spatial-frequency components of Landsat images that are neighbors in the temporal domain. Meanwhile, high-spatialfrequency components are predicted by a weighted average of high-spatial-frequency components of Landsat images alone. The second novelty is that the method has demonstrated good performance using only one input Landsat image and a pair of MODIS images. The technique has been tested using several Landsat and MODIS images for a study area from Central North Carolina (WRS-2 path/row 16/35 in Landsat and H/V11/5 in MODIS), acquired in 2001. NDVI images that were calculated from the study area were used as input to the algorithm. The technique was tested experimentally by predicting existing Landsat images, and we obtained R2 values in the range 0.70 to 0.92 for estimated Landsat images in the red band, and 0.62 to 0.89 for estimated NDVI images.
Autonomous hyperspectral UAS photogrammetry for environmental monitoring applications
Authors: Honkavaara E. , Hakala T. , Markelin L. , Jaakkola A. , Saari H. , Ojanen H. , Pölönen I. , Tuominen S. , Näsi R. , Rosnell T. , Viljanen N.
Published: November 2014

Abstract. The unmanned airborne system (UAS) remote sensing using lightweight multi- and hyperspectral imaging sensors offer new possibilities for the environmental monitoring applications. Based on the accurate measurements of the way in which the object reflect and emit energy, wide range of affecting variables can be monitored. Condition for reliable applications is reliable and accurate input data. In many applications, installation of geometric and radiometric reference targets in the object area is challenging, for instance, in forest or water areas. On the other hand, UASs are often operated in very poor conditions, under clouds or under variable cloud cover. Our objective is to develop an autonomous hyperspectral UAS imaging system and data processing chain that does not require any ground reference targets. Prerequisites for this kind of a system are an appropriate sensor setup, stable and wellcalibrated instruments and rigorous data processing. In this paper, we will describe the new hyperspectral UAS imaging system that is under development. Important applications for the proposed system include precision agriculture, forest monitoring and water quality monitoring. Finally, we will consider the use of the system in forest inventory application and present the first results of the summer 2014 campaigns.
Performance of a real-time sensor and processing system on a helicopter
Authors: Kurz F. , Rosenbaum D. , Meynberg O. , Mattyus G. , Reinartz P.
Published: November 2014

Abstract. A new optical real-time sensor system (4k system) on a helicopter is now ready to use for applications during disasters, mass events and traffic monitoring scenarios. The sensor was developed light-weighted, small with relatively cheap components in a pylon mounted sideward on a helicopter. The sensor architecture is finally a compromise between the required functionality, the development costs, the weight and the sensor size. Aboard processors are integrated in the 4k sensor system for orthophoto generation, for automatic traffic parameter extraction and for data downlinks. It is planned to add real-time processors for person detection and tracking, for DSM generation and for water detection. Equipped with the newest and most powerful off-the-shelf cameras available, a wide variety of viewing configurations with a frame rate of up to 12 Hz for the different applications is possible. Based on three cameras with 50 mm lenses which are looking in different directions, a maximal FOV of 104° is reachable; with 100 mm lenses a ground sampling distance of 3.5 cm is possible at a flight height of 500 m above ground. In this paper, we present the first data sets and describe the technical components of the sensor. The effect of vibrations of the helicopter on the GNSS/IMU accuracy and on the 4k video quality is analysed. It can be shown, that if the helicopter hoovers the rolling shutter effect affects the 4k video quality drastically. The GNSS/IMU error is higher than the specified limit, which is mainly caused by the vibrations on the helicopter and the insufficient vibrational absorbers on the sensor board.
Experiences with Light Weight Fixed Wing Aerial Mapping UAVs
Authors: Mayr W.
Published: November 2014

Abstract. UAVs seem to be the next "cloud" like topic, not only in geomatics. Unmanned Airborne Vehicles are not a wonder-tool, but a complementary approach to resolve some tasks more efficiently than before or at all. Since 2006 we commercially apply fixed wing, light weight UAVs for aerial mapping purposes. In this paper we like to share our experiences with UAVs of less than 5 kg and illuminate some limitations as well as potentials. Whereas multicopters seem to be in use everywhere, fixed wing UAVs more frequently seem to be applied in specific and geospatially oriented applications. Having processed several hundred UAV aerial mapping projects there forms a stable picture of this technology. Our impressions on durability, handling, and reliability of fixed wing UAVs get presented. We report on our day-to-day experiences and point to often simple hurdles to overcome. Various cameras were flown, different approaches of handling their geometries with different software packages were undertaken. Remarks to achieved geometric accuracies as well as the consequences of using dual frequency GPS instead of simple yet great single frequency GPS are discussed. All of this packed into the subsequent paper.
Scalable Evolutionary Computation for Efficient Information Extraction from Remote Sensed Imagery
Authors: Almutairi L. M. , Shetty S. , Momm H. G.
Published: November 2014

Abstract. Evolutionary computation, in the form of genetic programming, is used to aid information extraction process from high-resolution satellite imagery in a semi-automatic fashion. Distributing and parallelizing the task of evaluating all candidate solutions during the evolutionary process could significantly reduce the inherent computational cost of evolving solutions that are composed of multichannel large images. In this study, we present the design and implementation of a system that leverages cloud-computing technology to expedite supervised solution development in a centralized evolutionary framework. The system uses the MapReduce programming model to implement a distributed version of the existing framework in a cloud-computing platform. The proposed system has two major subsystems; (i) data preparation: the generation of random spectral indices; and (ii) distributed processing: the distributed implementation of genetic programming, which is used to spectrally distinguish the features of interest from the remaining image background in the cloud computing environment in order to improve scalability. The proposed system reduces response time by leveraging the vast computational and storage resources in a cloud computing environment. The results demonstrate that distributing the candidate solutions reduces the execution time by 91.58%. These findings indicate that such technology could be applied to more complex problems that involve a larger population size and number of generations.
Spatial analysis from remotely sensed observations of Congo basin of East African high Land to drain water using gravity for sustainable management of low laying Chad basin of Central Africa
Authors: Modu B. , Herbert B.
Published: November 2014

Abstract. The Chad basin which covers an area of about 2.4 million kilometer square is one of the largest drainage basins in Africa in the centre of Lake Chad .This basin was formed as a result of rifting and drifting episode, as such it has no outlet to the oceans or seas. It contains large area of desert from the north to the west. The basin covers in part seven countries such as Chad, Nigeria, Central African Republic, Cameroun, Niger, Sudan and Algeria. It is named Chad basin because 43.9% falls in Chad republic. Since its formation, the basin continues to experienced water shortage due to the activities of Dams combination, increase in irrigations and general reduction in rainfall. Chad basin needs an external water source for it to be function at sustainable level, hence needs for exploitation of higher east African river basin called Congo basin; which covers an area of 3.7 million square km lies in an astride the equator in west-central Africa-world second largest river basin after Amazon. The Congo River almost pans around republic of Congo, the democratic republic of Congo, the Central African Republic, western Zambia, northern Angola, part of Cameroun, and Tanzania. The remotely sensed imagery analysis and observation revealed that Congo basin is on the elevation of 275 to 460 meters and the Chad basin is on elevation of 240 meters. This implies that water can be drained from Congo basin via headrace down to the Chad basin for the water sustainability.
Examining the possibility of correcting imagery acquired for the purpose of obtaining spectral reflectance coefficients in the infrared range using photometric measurements
Authors: Orych A. , Walczykowski P. , Kedzierski M. , Fryskowska A.
Published: November 2014

Abstract. The purpose of this paper is to determine the possibility of using photometric measurements in order to correct imagery acquired in the 900–1700 nm range. This imagery is acquired for the purpose of acquiring spectral reflectance coefficients in variable lighting conditions. This paper will present a series of experiments, the problems encountered and obtained results. The main aim of this research was to determine a link between these two quantities (luminance and irradiance) in order to be able to eliminate the need of using such a spectroradiometer (a large, heavy and costly instrument) when acquiring spectral reflectance data from a XEVA XS-1.7.320 camera mounted on an UAV without using a reference panel.
Study of Morphologic Change in Poyang Lake Basin Caused by Sand Dredging Using Multi-temporal Landsat Images and DEMs
Authors: Qi S. , Zhang X. , Wang D. , Zhu J. , Fang C.
Published: November 2014

Abstract. Sand dredging has been practiced in rivers, lakes, harbours and coastal areas in recent years in China mostly because of demand from construction industry as building material. Sand dredging has disturbed aquatic ecosystems by affecting hydrological processes, increasing content of suspended sediments and reducing water clarity. Poyang Lake, connecting with Yangtze River in the lower reaches of the Yangtze River, is the largest fresh water lake in China. Sand dredging in Poyang Lake has been intensified since 2001 because such practice was banned in Yangtze River and profitable. In this study, the morphologic change caused by sand dredging in Poyang Lake basin was analysed by overlaying two DEMs acquired in 1952 and 2010 respectively. Since the reflectance of middle infrared band for sand dredging vessel is much higher than that of water surface, sand dredging vessels were showed as isolated grey points and can be counted in the middle infrared band in 12 Landsat images acquired in flooding season during 2000~2010. Another two Landsat images (with low water level before 2000 and after 2010) were used to evaluate the morphologic change by comparing inundation extent and shoreline shape. The following results was obtained: (1) vessels for sand dredging are mainly distributed in the north of Poyang Lake before 2007, but the dredging area was enlarged to the central region and even to Gan River; (2) sand dredging area reached to about 260.4 km2 and is mainly distributed in the north of Songmen Mountain and has been enlarged to central of Poyang Lake from the distribution of sand vessels since 2007. Sand dredged from Poyang Lake was about 1.99 × 109 m3 or 2448 Mt assuming sediment bulk density of 1.23 t m−3. It means that the magnitude of sand mining during 2001–2010 is almost ten times of sand depositions in Poyang Lake during 1955–2010; (3) Sand dredging in Poyang Lake has alternated the lake capacity and discharge section area, some of the watercourse in the northern channel was enlarged by more than 1 km when in low lake level. This study is useful to understand the change of hydrological system, especially the drying up trend in Poyang Lake in recent autumns and winters.
RECOVER: An Automated, Cloud-Based Decision Support System for Post-Fire Rehabilitation Planning
Authors: Schnase J. L. , Carroll M. L. , Weber K. T. , Brown M. E. , Gill R. L. , Wooten M. , May J. , Serr K. , Smith E. , Goldsby R. , Newtoff K. , Bradford K. , Doyle C. , Volker E. , Weber S.
Published: November 2014

Abstract. RECOVER is a site-specific decision support system that automatically brings together in a single analysis environment the information necessary for post-fire rehabilitation decision-making. After a major wildfire, law requires that the federal land management agencies certify a comprehensive plan for public safety, burned area stabilization, resource protection, and site recovery. These burned area emergency response (BAER) plans are a crucial part of our national response to wildfire disasters and depend heavily on data acquired from a variety of sources. Final plans are due within 21 days of control of a major wildfire and become the guiding document for managing the activities and budgets for all subsequent remediation efforts. There are few instances in the federal government where plans of such wide-ranging scope and importance are assembled on such short notice and translated into action more quickly. RECOVER has been designed in close collaboration with our agency partners and directly addresses their high-priority decision-making requirements. In response to a fire detection event, RECOVER uses the rapid resource allocation capabilities of cloud computing to automatically collect Earth observational data, derived decision products, and historic biophysical data so that when the fire is contained, BAER teams will have a complete and ready-to-use RECOVER dataset and GIS analysis environment customized for the target wildfire. Initial studies suggest that RECOVER can transform this information-intensive process by reducing from days to a matter of minutes the time required to assemble and deliver crucial wildfire-related data.
Integrating the UAS in Undergraduate Teaching and Research – Opportunities and Challenges at University of North Georgia
Authors: Sharma J. B. , Hulsey D.
Published: November 2014

Abstract. The University of North Georgia (UNG) has begun to evaluate both fixed and rotary UAS platforms across the departments to evaluate their potential for furthering both student learning experiences and undergraduate research. A research project of the Institute for Spatial Analysis (IESA) at UNG has acquired the fixed wing eBee UAS and is currently piloting its integration into the undergraduate geospatial science curriculum. Limited very low altitude, line of sight calibration runs within areas of our campus have help us understand the capabilities that this technology brings to learning and research opportunities at UNG. In our pilot area of study on the UNG Gainesville Campus, we will collect overlapping imagery and generate 3-D models. These models will be compared with models based on LiDAR data. Geographic Object Based Image Analysis (GEOBIA) methods are essential to the analysis of voluminous high resolution UAS data and the associated computational and regulatory issues are discussed. Several future interdisciplinary projects are envisaged with the eBee UAS and this project helps establish their viability.
DTM generation in forest regions from satellite stereo imagery
Authors: Tian J. , Krauss T. , Reinartz P.
Published: November 2014

Abstract. Satellite stereo imagery is becoming a popular data source for derivation of height information. Many new Digital Surface Model (DSM) generation and evaluation methods have been proposed based on these data. A novel Digital Terrain Model (DTM) extraction method based on the DSM from satellite stereo imagery is proposed in this paper. Instead of directly filtering the DSM, firstly a single channel based classification method is proposed. In this step, no multi-spectral information is used, because for some stereo sensors, like Cartosat-1, only panchromatic channels are available. The proposed classification method adopts the random forests method to get initial probability maps of the four main classes in forest regions (high-forest, low-forest, ground, and buildings). To cover the pepper and salt effect of this pixel based classification method, the probability maps are further filtered based on the adaptive Wiener filtering. Then a cube-based greedy strategy is applied in generating the final classification map from these refined probability maps. Secondly, the height distances between neighboring regions are calculated along the boundary regions. These height distances can be used to estimate the relative region heights. Thirdly, the DTM is extracted by subtracting these relative region heights from the DSM in the order of: buildings – low forest – high forest. In the end, the extracted DTM is further smoothed using median filter. The proposed DTM extraction method is finally tested on satellite stereo imagery captured by Cartosat-1. Quality evaluation is performed by comparing the extracted DTMs to a reference DTM, which is generated from the last return airborne laser scanning point cloud.
A mobile platform with a catadioptric sensor
Authors: Tommaselli A. M. G. , Marcato Junior J. , Olivete A. L. , de Moraes M. V. A.
Published: November 2014

Abstract. The aim of this paper is to present a mobile catadioptric omnidirectional vision system composed of a camera and a cone-shaped mirror integrated with a direct georeferencing system. The relationship between image and object space is established with generic/empiric or physical models. The models were implemented and tested with real data and some results are presented. The results showed that accuracies around 5 cm in planimetry can be achieved, which is suitable for several applications, including the generation of control scenes that was the original motivation of this work.
Pre-processing of Xeva-XS imagery for determining spectral reflectance coefficients in laboratory conditions
Authors: Walczykowski P. , Orych A. , Kedzierski M. , Fryskowska A.
Published: November 2014

Abstract. There are two different methodologies which can be used to acquire imagery from which it would be possible to obtain spectral reflectance characteristics – the first based on images of a scene in which a reference panel had been included, and the second based on precisely selected exposure parameters. This paper is concerned with the first of these two methods based on experiments conducted using a 14bit XEVA XS-1.7.320 infrared sensor. The paper firstly describes the effect of different exposure settings on the accuracy with which we can later determine the spectral reflectance coefficients. The next step when working with such imagery in laboratory conditions is to eliminate the effect of the uneven distribution of illumination. In the paper we present two proposed methods for eliminating the uneven distribution of illumination – an additive method and a quotient method. After that it is essential to stretch the DN values. Once again we investigated two possible methods of doing this – firstly, by stretching the data using only the white reference panel, adjusting the maxDN value of the image of the surface of the reference panel to 95%. The second method additionally adds a second reference point – a black reference panel which reflects 5% of incident radiation. The spectral reflectance coefficients of chosen samples acquired using all of the above mentioned methods are compared with reference data obtained using a spectroradiometer. Establishing the most optimal methodologies will greatly increase the accuracy of obtained spectral response coefficients, which at the same time will increase the accuracy with which, in this case, water pollutants will be identified.
Noise Filtering of Remotely Sensed Images using Iterative Thresholding of Wavelet and Curvelet Transforms
Authors: Ansari R. A. , Mohan B. K.
Published: November 2014

Abstract. This article presents techniques for noise filtering of remotely sensed images based on Multi-resolution Analysis (MRA). Multiresolution techniques provide a coarse-to-fine and scale-invariant decomposition of images for image interpretation. The multiresolution image analysis methods have the ability to analyze the image in an adaptive manner, capturing local information as well as global information. Further, noise being one of the biggest problems in image analysis and interpretation for further processing, is effectively handled by multi-resolution methods. The paper aims at the analysis of noise filtering of image using wavelets and curvelets on high resolution multispectral images acquired by the Quickbird and medium resolution Landsat Thematic Mapper satellite systems. To improve the performance of noise filtering an iterative thresholding scheme for wavelets and curvelets is proposed for restoring the image from its noisy version. Two comparative measures are used for evaluation of the performance of the methods for denoising. One of them is the signal to noise ratio and the second is the ability of the noise filtering scheme to preserve the sharpness of the edges. By both of these comparative measures, the curvelet with iterative threshold has proved to be better than the others. Results are illustrated using Quickbird and Landsat images for fixed and iterative thresholding.
Ground deformation monitoring using RADARSAT-2 DInSAR-MSBAS at the Aquistore CO2 storage site in Saskatchewan (Canada)
Authors: Czarnogorska M. , Samsonov S. , White D.
Published: November 2014

Abstract. The research objectives of the Aquistore CO2 storage project are to design, adapt, and test non-seismic monitoring methods for measurement, and verification of CO2 storage, and to integrate data to determine subsurface fluid distributions, pressure changes and associated surface deformation. Aquistore site is located near Estevan in Southern Saskatchewan on the South flank of the Souris River and west of the Boundary Dam Power Station and the historical part of Estevan coal mine in southeastern Saskatchewan, Canada. Several monitoring techniques were employed in the study area including advanced satellite Differential Interferometric Synthetic Aperture Radar (DInSAR) technique, GPS, tiltmeters and piezometers. The targeted CO2 injection zones are within the Winnipeg and Deadwood formations located at > 3000 m depth. An array of monitoring techniques was employed in the study area including advanced satellite Differential Interferometric Synthetic Aperture Radar (DInSAR) with established corner reflectors, GPS, tiltmeters and piezometers stations. We used airborne LIDAR data for topographic phase estimation, and DInSAR product geocoding. Ground deformation maps have been calculated using Multidimensional Small Baseline Subset (MSBAS) methodology from 134 RADARSAT-2 images, from five different beams, acquired during 20120612–20140706. We computed and interpreted nine time series for selected places. MSBAS results indicate slow ground deformation up to 1 cm/year not related to CO2 injection but caused by various natural and anthropogenic causes.
Synergy Between LiDAR and Image Data in Context of Building Extraction
Authors: Dal Poz A. P.
Published: November 2014

Abstract. This paper compares the paradigms of LiDAR and aerophotogrammetry in the context of building extraction and briefly discusses a photogrammetric strategy for refining building roof polyhedrons previously extracted from LiDAR data. In general, empirical and theoretical studies have confirmed that LiDAR-based methodologies are more suitable in extracting planar roof faces and ridges of the roof, whereas the aerophotogrammetry are more suitable in extracting building roof outlines. In order to exemplify how to explore these properties, it is presented a photogrammetric method for refining 3D building roof contours extracted from airborne LiDAR data. Examples of application are provided for this refining approach.
Evaluation of Skybox Video and Still Image products
Authors: d'Angelo P. , Kuschk G. , Reinartz P.
Published: November 2014

Abstract. The SkySat-1 satellite lauched by Skybox Imaging on November 21 in 2013 opens a new chapter in civilian earth observation as it is the first civilian satellite to image a target in high definition panchromatic video for up to 90 seconds. The small satellite with a mass of 100 kg carries a telescope with 3 frame sensors. Two products are available: Panchromatic video with a resolution of around 1 meter and a frame size of 2560 × 1080 pixels at 30 frames per second. Additionally, the satellite can collect still imagery with a swath of 8 km in the panchromatic band, and multispectral images with 4 bands. Using super-resolution techniques, sub-meter accuracy is reached for the still imagery. The paper provides an overview of the satellite design and imaging products. The still imagery product consists of 3 stripes of frame images with a footprint of approximately 2.6 × 1.1 km. Using bundle block adjustment, the frames are registered, and their accuracy is evaluated. Image quality of the panchromatic, multispectral and pansharpened products are evaluated. The video product used in this evaluation consists of a 60 second gazing acquisition of Las Vegas. A DSM is generated by dense stereo matching. Multiple techniques such as pairwise matching or multi image matching are used and compared. As no ground truth height reference model is availble to the authors, comparisons on flat surface and compare differently matched DSMs are performed. Additionally, visual inspection of DSM and DSM profiles show a detailed reconstruction of small features and large skyscrapers.
Changes in soil organic carbon and nitrogen capacities of Salix cheilophila Schneid along a revegetation chronosequence in semi-arid degraded sandy land of the Gonghe Basin, Tibet Plateau
Authors: Yu Y. , Jia Z. Q.
Published: November 2014

Abstract. The Gonghe Basin is a sandified and desertified region of China, but the distribution of soil organic carbon (SOC) and total nitrogen (TN) along the cultivation chronosequence across this ecologically fragile region is not well understood. This study was carried out to understand the effects of restoration with Salix cheilophila for different periods of time (6, 11, 16, 21 years) to test whether it enhanced C and N storage. Soil samples, in four replications from seven depth increments (0–10, 10–20, 20–30, 30–50, 50–100, 100–150 and 150–200 cm), were collected in each stand. Soil bulk density, SOC, TN, aboveground biomass and root biomass were measured. Results indicated that changes occurred in both the upper and deeper soil layers with an increase in revegetation time. The 0–200 cm soil showed that the 6-year stand gained 3.89 Mg C ha−1 and 1.00 Mg N ha−1, which accounted for 40.82% of the original SOC and 11.06% of the TN of the 0-year stand. The 11-year stand gained 7.82 Mg C ha−1 and 1.98 Mg N ha−1 in the 0–200 cm soil layers, accounting for 58.06% of the SOC and 19.80% of the TN of the 0-year stand. The 16-year stand gained 11.32 Mg C ha−1 and 3.30 Mg N ha−1 in the 0–200 cm soil layers, accounting for 66.71% of the SOC and 21.98% of the TN of the 0-year stand. The 21-year stand gained 13.05 Mg C ha−1 and 5.45 Mg N ha−1 from the same soil depth, accounting for 69.79% of the SOC and 40.47% of the TN compared with the 0-year stand. The extent of these changes depended on soil depth and plantation age. The results demonstrated that, as stand age increased, the storage of SOC and TN increased. These results further indicated that restoration with S. cheilophila has positive impacts on the Gonghe Basin and has increased the capacity of SOC sequestration and N storage. The shrub's role as carbon sink is compatible with system management and persistence. The findings are significant for assessing C and N sequestration accurately in semi-arid degraded high, cold sandy regions in the future.
Short-Term Complications Associated With TPLO in Dogs Using 2.0 and 2.7 mm Plates
Authors: Garnett Steve D. , Daye R. Mark
Published: November 2014

The purpose of this study was to evaluate short-term complications associated with the tibial plateau leveling osteotomy (TPLO) procedure in dogs of small and medium sizes. These study findings could then be compared with similar studies in dogs of all sizes. Ninety-eight procedures (82 dogs) using 2 or 2.7 mm TPLO plates were included spanning a 6 yr period with a minimum of an 8 wk follow-up period. The overall complication rate was 36%. Complications were grouped into three categories: intraoperative (2%), those occurring up to 2 wk postoperatively (11%), and those occurring >2 wk postoperatively (30%). Radiographic evidence of delayed healing of the TPLO osteotomy site was the most common complication in the dogs (9%), none of which had clinical signs attributed to delayed healing. Other common complications included patellar tendon thickening (8%) and tibial tuberosity fracture (6%). Seven percent of the complications were considered major (requiring additional surgical intervention). Fifty-two percent of complications did not require treatment. Short-term complications should not dissuade an experienced surgeon from performing the TPLO procedure in small- and medium-sized dogs.
Biogeoclimatic classifications: land models useful for ecological forest studies
Authors: Elena Rosselló R.
Published: November 2014

This paper deals with the usefulness of biogeoclimatic land classifications in the development of forest ecological studies, at the ecosystem level on forest site surveys, as well as at supra-ecosystem level on landscape studies. For these purposes, two past experiences carried out in Spain using the ITE land classification system, are reviewed. As a first example, a land classification developed at sub-regional level is used as sample stratification framework for modelling the land suitability for Pinus nigra subesp. nigra plantations of Navarre. The required methodological phases are described, until the final design of a land model useful for forest managers and planners. As a second example, it is analysed the usefulness of the biogeoclimatic land classification of Spain (CLATERES) as sample stratification system for ecological landscape monitoring. The model validation is achieved by testing the correlation among CLATERES land stratification and landscape composition of a sample of 206 land units belonging to the Spanish network of rural landscapes (REDPARES). A highly significant correlation among biogeoclimatic classes and landscape composition classes allow us to use CLATERES as a geo-statistical model able to extrapolate to the whole Spain the results obtained from 206 REDPARES landscapes.
Responses of plants to soil flooding
Authors: Pardos J. A.
Published: November 2014

Firstly, flooding is considered from the point of view of plants, afterwards from an edaphological perspective by taking into account the limitation of oxygen in hydromorphic soils and changes on them, specially ethylene accumulation. Waterlogging is shown as a kind of stress to plants. Mechanisms of flood tolerance are described and the influence of taxon, plant age, temporality and soil is emphasized. The effects on seed germination and establishment of riparian species on flooded soils are shown. The anatomical and physiological symptoms induced by waterlogging are enumerated and related to the overproduction of ethylene by the plants, its exogenous application being the cause of similar effects on them. A description of the effects and resistance to waterlogging stress (artificially induced) in some representative forest trees, finishes the revision.
Sequestration of C in a Spanish chestnut coppice
Authors: Gallardo Lancho J. F. , González Mª. I.
Published: November 2014

The balance of C is one of the most important balances in nature, since it determines the flow of organic matter, governs that of other bioelements (N, P, S, etc.), and controls the content of CO2 in the atmosphere. The objective of this work was to quantify the C sequestration in a Sweet chestnut forest located in the «Sierra de Gata» Mountains (Central-Western Spain). This chestnut coppice is located in the south edge of the «Sierra de Gata» mountains (province of Cáceres, central-western Spain). Climatic characteristics are mean temperature 15 ºC and mean annual-rainfall 1,158 mm yr-1, i. e., sub-humid Mediterranean. The soils are an association of haplic Umbrisols and Leptosols. This coppice of Castanea sativa is 25 years old, i. e., the usual rotation time. The accumulations of C in the tree biomass was 58 Mg C ha-1 yr-1, the calculated litter decomposition-constants 0.39 yr-1, and the aboveground annual-production 5.25 Mg C ha-1 yr-1. The accumulation of C in the Ah horizons was 143 Mg C ha-1. On calculating a global balance, inputs of C into this forest ecosystem are always greater than the C outputs, the excess being 4.7 Mg C ha-1 yr-1.
Effect of silviculture on the nutrient exports along the rotation in tree fast-growing plantation species of northern Spain
Authors: Rodríguez-Soalleiro R. , Balboa M. , Álvarez González J. G. , Merino A. , Sánchez F.
Published: November 2014

This paper deals with the evaluation of the amount of nutrients removed and reincorporated after clearcut or thinning in the tree main commercial species of northern Spain: Eucalyptus globulus, Pinus pinaster and Pinus radiata. A simulation of different sylvicultural alternatives was done using stand growth models integrated with control functions which allow to cope with an individual-tree level of detail and a determination of the components of the total aboveground biomass. The high annual rates of extraction in the eucalypts plantations and the adaptation of maritime pine to poor sites where low amounts of nutrients were removed are demonstrated. Heavy thinning sylvicultural regimes give a better nutrient economy for pines. The harvest of no debarked wood is very important for the amount of extractions, particularly in eucalypts.
New data on charcoal and fossil wood of Pinus pinaster Aiton in the Holocene from the Iberian Peninsula
Authors: Alcalde Olivares C. , García Amorena I. , Gómez Manzaneque F. , Maldonado Ruiz J. , Morla Juaristi C. , Postigo Mijarra J. M. , Rubiales Jiménez J. M. , Sánchez Hernando L. J.
Published: November 2014

The study of ligneous fossil remains (charcoal and wood) corresponding to three sites located in the interior of the Iberian Peninsula is presented. The chronologies established by means of radiocarbon or relative dating (archaeological) situate all the samples in the last phase of the Holocene. In the three deposits Pinus pinaster has been identified and there have being made other taxonomic contributions. A review of previous Pinus pinaster findings registered in the Peninsula is exposed and other considerations are made on the importance of this taxon in the Iberian vegetal landscape during the end of the Quaternary.
Contribution to the entomofaunal study of the Sierra Selladores-Contadero (Spain)
Authors: Notario A. , Castresana L.
Published: November 2014

By sundry capture methods it is achieved an insect collecting in 6 plots that are located in Monte de Selladores-Contadero, Jaén (Spain). The taxonomic analysis about 4.787 specimen gives as a result the identification of 275 species belonging at 12 Orders and 82 Families.
The role of mast cells in atherosclerosis
Authors: Wezel A. , Quax P. H. A. , Kuiper J. , Bot I.
Published: November 2014

Rupture of an atherosclerotic plaque is the major underlying cause of adverse cardiovascular events such as myocardial infarction or stroke. Therapeutic interventions should therefore be directed towards inhibiting growth of atherosclerotic lesions as well as towards prevention of lesion destabilization. Interestingly, the presence of mast cells has been demonstrated in both murine and human plaques, and multiple interventional murine studies have pointed out a direct role for mast cells in early and late stages of atherosclerosis. Moreover, it has recently been described that activated lesional mast cells correlate with major cardiovascular events in patients suffering from cardiovascular disease.

This review focuses on the effect of different mast cell derived mediators in atherogenesis and in late stage plaque destabilization. Also, possible ligands for mast cell activation in the context of atherosclerosis are discussed. Finally, we will elaborate on the predictive value of mast cells, together with therapeutic implications, in cardiovascular disease.
Competencia científica de estudiantes que ingresan y egresan de la Universidad
Authors: Falicoff Claudia Beatriz , Domínguez Castiñeiras José Manuel , Odetti Héctor Santiago
Published: November 2014

En el presente estudio se presentan resultados que ponen de manifiesto con qué competencia científica ingresan los estudiantes en la Facultad de Bioquímica y Ciencias Biológicas (primer curso de las carreras de Bioquímica y de Biotecnología de la Universidad Nacional del Litoral de Santa Fe, Argentina) y con cuál egresan de ella (quinto curso de las mismas carreras). Para obtener la información, se elaboraron dos cuestionarios ad hoc: uno con preguntas que abarcan las tres subcompetencias científicas y otro para explorar la influencia de ciertas características del contexto sobre el rendimiento en estas. Los resultados indican que los ingresantes parten de un nivel bajo en el rendimiento de todas las subcompetencias científicas evaluadas. Luego de la instrucción, en los últimos años, el desarrollo es favorable y de manera más apreciable en Bioquímica que en Biotecnología.
Nueva propuesta teórica sobre obstáculos epistemológicos de aprendizaje. El caso del metabolismo de los carbohidratos
Authors: Garófalo Sofía Judith , Alonso Manuel , Galagovsky Lydia
Published: November 2014

La utilización de tres modelos científicos definidos ad hoc sobre el metabolismo de los hidratos de carbono permitió analizar numerosos errores detectados en el aprendizaje de estudiantes universitarios. Este análisis llevó a considerar la existencia de dos clases diferentes de obstáculos epistemológicos subyacentes al aprendizaje (OEA): los de tipo brecha y los de tipo puente. Los primeros se manifiestan por la falta de modelos mentales en los que los estudiantes puedan anclar o engarzar sus aprendizajes; y los segundos se corresponderían a ideas consolidadas para el sujeto que actuarían como modelos mentales idiosincrásicos, funcionales pero erróneos desde el punto de vista científico. Este aporte teórico, basado en evidencias empíricas, constituye una alternativa de análisis que va más allá de la simple enumeración de los errores de los estudiantes.