bluuebunny/crossref_metadata_2025 huggingface dataset:
Nitrogen restricts future treeline advance in the sub-arctic
Authors: Gustafson Adrian , Miller Paul A. , Björk Robert , Olin Stefan , Smith Benjamin
Published: June 2021

Abstract. Arctic environmental change has induced shifts in high latitude plant community composition and stature with impli-cations for Arctic carbon cycling and energy exchange. Two major components of high latitude ecosystems undergoing change is the advancement of trees into treeless tundra and the increased abundance and size of shrubs. How future changes in key climatic and environmental drivers will affect distributions of major ecosystem types is an active area of research. Dynamic Vegetation Models (DVMs) offer a way to investigate multiple and interacting drivers of vegeta-tion distribution and ecosystem function. We employed the LPJ-GUESS DVM over a subarctic landscape in northern Sweden, Torneträsk. Using a highly resolved climate dataset we downscaled CMIP5 climate data from three Global Climate Models and two 21st century future scenarios (RCP2.6 and RCP8.5) to investigate future impacts of climate change on these ecosystems. We also performed three model experiments where we factorially varied drivers (climate, nitrogen deposition and [CO2]) to disentangle the effects of each on ecosystem properties and functions. We found that treelines could advance by between 45 and 195 elevational meters in the landscape until the year 2100, depending on the scenario. Temperature was a strong, but not the only, driver of vegetation change. Nitrogen availability was identi-fied as an important modulator of treeline advance. While increased CO2 fertilisation drove productivity increases it did not result in any range shifts of trees. Treeline advance was realistically simulated without any temperature depend-ence on growth, but biomass was overestimated. As nitrogen was identified as an important modulator of treeline ad-vance, we support the idea that accurately representing plant-soil interactions in models will be key to future predic-tions Arctic vegetation change.
Sequential dehydration of the phosphate–sulfate association from Gura Dobrogei Cave, Dobrogea, Romania
Authors: Dumitraş Delia-Georgeta , Marincea Ştefan
Published: June 2021

Abstract. A rich association of primary guano minerals, including
taranakite, hydroxylapatite, brushite and gypsum with relicts of illite,
kaolinite, alpha (low) quartz and calcite, was identified in the fossil
bat guano deposit from Gura Dobrogei Cave, Dobrogea County, Romania. Gypsum
and Ca phosphates developed preferentially on the carbonate bedrock or on
fallen carbonate blocks in the guano mass, whereas taranakite was identified
in the clay-rich, detritic sequences. The mineral species from the cave were
characterized by optical methods, scanning electron microscopy, X-ray powder
diffraction, Fourier-transform infrared and inductively coupled plasma–atomic emission spectrometry analysis. Chemically induced local dehydration
of primary minerals, characterized by low temperatures (up to 100 ∘C or even lower) and critically depending on exothermal reactions in the
guano mass, prompted the formation of a secondary association, consisting
of francoanellite, bassanite and monetite. Topotactic substitutions were
observed in the cases of francoanellite on taranakite, bassanite on gypsum
and monetite on brushite. In its turn, ardealite was partially replaced by
monetite and bassanite. The sequential dehydration process seems driven by
the degradation of organic matter by microbial action and also, presumably,
by other exothermic reactions at local scale (e.g., oxidation of ammonia,
allogenic pyrite or other organic compounds).
Streamflow indices to identify catchment drivers of hydrograph
Authors: Mathai Jeenu , Mujumdar Pradeep
Published: June 2021

Abstract. Streamflow indices are flow descriptors that quantify the streamflow dynamics, which are usually determined for a specific basin and are distinct from other basin features. The flow descriptors are appropriate for large-scale and comparative hydrology studies, independent of statistical assumptions and can distinguish signals that indicate basin behavior over time. In this paper, the characteristic features of the hydrograph's temporal asymmetry due to its different underlying hydrologic processes are primarily highlighted. Streamflow indices linked to each limb of the hydrograph within the time-irreversibility paradigm are distinguished with respect to its processes driving the rising and falling limbs. Various streamflow indices relating the rising and falling limbs, and the catchment attributes such as climate, topography, vegetation, geology and soil are then correlated. Finally, the key attributes governing rising and falling limbs are identified. The novelty of the work is on differentiating hydrographs by their time irreversibility property and offering an alternative way to recognize primary drivers of streamflow hydrographs. A set of streamflow indices at the catchment scale for 671 basins in the Contiguous United States (CONUS) is presented here. These streamflow indices complement the catchment attributes provided earlier (Addor et al., 2017) for the CAMELS data set. A series of spatial maps describing the streamflow indices and their regional variability over the CONUS is illustrated in this study.
PREDICTING THE INFRARED UAV IMAGERY OVER THE COAST
Authors: Collin A. , James D. , Mury A. , Letard M. , Guillot B.
Published: June 2021

Abstract. The infrared (IR) imagery provides additional information to the visible (red-green-blue, RGB) about vegetation, soil, water, mineral, or temperature, and has become essential for various disciplines, such as geology, hydrology, ecology, archeology, meteorology or geography. The integration of the IR sensors, ranging from near-IR (NIR) to thermal-IR through mid-IR, constitutes a baseline for Earth Observation satellites but not for unmanned airborne vehicles (UAV). Given the hyperspatial and hypertemporal characteristics associated with the UAV survey, it is relevant to benefit from the IR waveband in addition to the visible imagery for mapping purposes. This paper proposes to predict the NIR reflectance from RGB digital number predictors collected with a consumer-grade UAV over a structurally and compositionally complex coastal area. An array of 15 000 data, distributed into calibration, validation and test datasets across 15 representative coastal habitats, was used to build and compare the performance of the standard least squares, decision tree, boosted tree, bootstrap forest and fully connected neural network (NN) models. The NN family surpassed the four other ones, and the best NN model (R2 = 0.67) integrated two hidden layers provided, each, with five nodes of hyperbolic tangent and five nodes of Gaussian activation functions. This perceptron enabled to produce a NIR reflectance spatially-explicit model deprived of original artifacts due to the flight constraints. At the habitat scale, sedimentary and dry vegetation environments were satisfactorily predicted (R2 > 0.6), contrary to the healthy vegetation (R2 < 0.2). Those innovative findings will be useful for scientists and managers tasked with hyperspatial and hypertemporal mapping.
AUTOMATIC INTEGRATION OF LASER SCANNING AND PHOTOGRAMMETRIC POINT CLOUDS: FROM ACQUISITION TO CO-REGISTRATION
Authors: Partovi T. , Dähne M. , Maboudi M. , Krueger D. , Gerke M.
Published: June 2021

Abstract. Laser scanning systems have been developed to capture very high-resolution 3D point clouds and consequently acquire the object geometry. This object measuring technique has a high capacity for being utilized in a wide variety of applications such as indoor and outdoor modelling. The Terrestrial Laser Scanning (TLS) is used as an important data capturing measurement system to provide high quality point cloud from industrial or built-up environments. However, the static nature of the TLS and complexity of the industrial sites necessitate employing a complementary data capturing system e.g. cameras to fill the gaps in the TLS point cloud caused by occlusions which is very common in complex industrial areas. Moreover, employing images provide better radiometric and edge information. This motivated a joint project to develop a system for automatic and robust co-registration of TLS data and images directly, especially for complex objects. In this paper, the proposed methods for various components of this project including gap detection from point cloud, calculation of initial image capturing configuration, user interface and support system for the image capturing procedures, and co-registration between TLS point cloud and photogrammetric point cloud are presented. The primarily results on a complex industrial environment are promising.
CHANGE DETECTION OF TIME-SERIES 3D POINT CLOUDS USING ROBUST PRINCIPAL COMPONENT ANALYSIS
Authors: Fuse T. , Yamano T.
Published: June 2021

Abstract. The chances of acquiring three-dimensional (3D) point clouds have recently increased with the emergence of laser scanners. Hence, 3D monitoring of various objects through the accumulation of “time-series 3D point clouds,” which are point clouds of the same place at different times, is possible. Change detection is a task that is indispensable in 3D monitoring. One of the most common change detection method of 3D point clouds is simple subtraction between two data. However, this method is vulnerable to various errors. Therefore, change detection methods that are robust to errors are required. In this study, we developed robust principal component analysis, which has become popular in the background modelling of video images, to robustly recognize changes in time-series 3D point clouds. We first applied the proposed method to time-series depth images and confirmed its accuracy. We then applied the method to the digital elevation models of Mt. Unzen, which were acquired between 2003 and 2016, to recognize yearly elevation changes. The results show that the proposed method robustly recognizes elevation changes with a properly set parameter.
AUTOMATION OF WINDOWS DETECTION FROM GEOMETRIC AND RADIOMETRIC INFORMATION OF POINT CLOUDS IN A SCAN-TO-BIM PROCESS
Authors: Macher H. , Roy L. , Landes T.
Published: June 2021

Abstract. The detection of openings based on point clouds is generally based on geometric features namely the X, Y and Z coordinates of points. Existing methods exploit geometric features but ignore most of the time other attributes as colour and intensity. Such information may be however particularly interesting to recognise and segment openings in facades. In this paper, the use of radiometric information, namely colour and intensity, is investigated for the segmentation of windows from façade point clouds. The assumption is made that windows are significantly different in terms of materials and colours to be distinguished from facade walls. The exploitation of colour and intensity are considered separately. A histogram analysis method is proposed for the exploitation of intensity information whereas a region growing method based on colorimetric distances is considered for the exploitation of colours. In order to refine the results, geometric information, and more precisely depth of points with regards to façade walls, are combined to radiometric information. Several combinations of attributes are considered and provide promising results for windows segmentation based on point clouds.
3D CONTENT GENERATION USING HYBRID AERIAL SENSOR DATA
Authors: Bacher U.
Published: June 2021

Abstract. In aerial data acquisition a new era started with the introduction of the first real hybrid sensor systems, like the Leica CityMapper-2. Hybrid in this context means the combination of an (oblique) camera system with a topographic LiDAR into an integrated aerial mapping system. By combining these complimentary sub-systems into one system the weaknesses of the one system could be compensated by using the alternative data source. An example is the mapping of low-light urban canyons, where image-based systems mostly produce unreliable results. For an LiDAR sensor the geometrical reconstruction of these areas is straight forward and leads to accurate results. The paper gives a detailed overview over the development and technical characteristics of hybrid sensor systems. The process of data acquisition is discussed and strategies for hybrid urban mapping are proposed. A hybrid sensor alone is just a part of the whole procedure to generate 3D content. As important as the senor itself is the workflow to generate the products. Here again a hybrid approach, with the processing of all datasets in one environment, is discussed. Special attention is paid to the hybrid orientation of the data and the integrated generation of base and enhanced products. The paper is rounded off by the discussion of the advantage of LiDAR data for the 3D Mesh generation for urban modelling.
ENHANCING GEOMETRIC EDGE DETAILS IN MVS RECONSTRUCTION
Authors: Stathopoulou E. K. , Rigon S. , Battisti R. , Remondino F.
Published: June 2021

Abstract. Mesh models generated by multi view stereo (MVS) algorithms often fail to represent in an adequate manner the sharp, natural edge details of the scene. The harsh depth discontinuities of edge regions are eventually a challenging task for dense reconstruction, while vertex displacement during mesh refinement frequently leads to smoothed edges that do not coincide with the fine details of the scene. Meanwhile, 3D edges have been used for scene representation, particularly man-made built environments, which are dominated by regular planar and linear structures. Indeed, 3D edge detection and matching are commonly exploited either to constrain camera pose estimation, or to generate an abstract representation of the most salient parts of the scene, and even to support mesh reconstruction. In this work, we attempt to jointly use 3D edge extraction and MVS mesh generation to promote edge detail preservation in the final result. Salient 3D edges of the scene are reconstructed with state-of-the-art algorithms and integrated in the dense point cloud to be further used in order to support the mesh triangulation step. Experimental results on benchmark dataset sequences using metric and appearance-based measures are performed in order to evaluate our hypothesis.
APPLICATION OF UAV OBLIQUE PHOTOGRAPHY IN REAL SCENE 3D MODELING
Authors: Zhou T. , Lv L. , Liu J. , Wan J.
Published: June 2021

Abstract. Aiming at the phenomenon that the traditional measurement methods cannot complete large-scale measurement in a short time, and the image quality obtained by remote sensing in cloudy and rainy areas is difficult to meet the demand, this paper puts forward the idea of using UAV tilt photography to build three-dimensional modeling of urban real scene. The UAV tilt photography technology is used to collect the image data of about 200 km2 in Wuzhishan City. By laying a small number of ground image control points, the aerial triangulation is used to establish the connection, and the three-dimensional modeling of the collected data is carried out. Through the field verification to verify the attribute information of ground objects, the accuracy is verified by using CORS system field coordinate collection. The results show that the ground property and mathematical accuracy of UAV tilt photography model meet the requirements, and can be effectively used in real 3D modeling.
INDOOR MAPPING OF A COMPLEX CULTURAL HERITAGE SCENE USING TLS AND HMLS LASER SCANNING
Authors: Oniga V. E. , Breaban A. I. , Alexe E. I. , Văsii C.
Published: June 2021

Abstract. Indoor mapping and modelling is an important research subject with application in a wide range of domains including interior design, real estate, cultural heritage conservation and restoration. There are multiple sensors applicable for 3D indoor modelling, but the laser scanning technique is frequently used because of the acquisition time, detailed information and accuracy. In this paper, the efficiency of the Maptek I-Site 8820 terrestrial scanner, which is a long-range laser scanner and the accuracy of a HMLS point cloud acquired with a mobile scanner, namely GeoSlam Zeb Horizon were tested for indoor mapping. Aula Magna “Carmen Silva” of the “Gheorghe Asachi” Technical University of Iasi is studied in the current paper since the auditorium interior creates a distinct environment that combines complex geometric structures with architectural lighting and for preserving its great cultural value, the monument has a national historical significance. The registration process of the TLS point clouds was done using two methods: a semi-automatic one with artificial targets and a completely automatic one, based on Iterative Closest Point (ICP) algorithm. The resulted TLS point cloud was analysed in relation to the HMLS point cloud by computing the M3C2 (Multiscale Model to Model Cloud Comparison), obtaining a standard deviation of 2.1 cm and by investigating the Hausdorff distances from which resulted a standard deviation (σ) of 1.6 cm. Cross-sections have been extracted from the HMLS and TLS point clouds and after comparing the sections, 80% of the sigma values are less or equal to 1 cm. The results show high potential of using HMLS and also a long-range laser scanner for 3D modelling of complex scenes, the occlusion effect in the case of TLS being only 5% of the scanned area.
BOAT-BASED MOBILE LASER SCANNING FOR SHORELINE MONITORING OF LARGE LAKES
Authors: Schneider D. , Blaskow R.
Published: June 2021

Abstract. In many applications, it is necessary to measure the shore areas of water bodies in three dimensions, for example for the planning of shore protection measures or regularly for water body monitoring. The complete recording of long shorelines can be very time-consuming with conventional methods. This paper presents the surveying of two lakes using a mobile laser scanner system. In order to close non-visible areas, the measurement was supplemented with terrestrial laser scanning and with UAV-supported photogrammetric methods. The result is an almost complete point cloud of the shoreline, each more than 8 km long, with a point spacing of a few millimetres.
A NOVEL METHOD FOR INSPECTION DEFECTS IN COMMERCIAL EGGS USING COMPUTER VISION
Authors: Valencia Y. M. , Majin J. J. , Taveira V. B. , Salazar J. D. , Stivanello M. E. , Ferreira L. C. , Stemmer M. R.
Published: June 2021

Abstract. The objective of this work is to compare the use of classical image processing approaches with deep learning approaches in a visual inspection system for defects in commercial eggs. Currently, many industries perform the detection of defects in eggs manually, this implies a large number of workers with long working hours who are exposed to visual fatigue and physical and mental discomfort. As a solution, this work proposes to develop an automatic inspection technique for defects in eggs using computer vision, capable of being operable in the industry. Different image processing approaches were evaluated in order to determine the best solution in terms of performance and processing time.
TRIANGULATION AND TIME-OF-FLIGHT BASED 3D DIGITISATION TECHNIQUES OF CULTURAL HERITAGE STRUCTURES
Authors: Altuntas C.
Published: June 2021

Abstract. This study aims to introduce triangulation and ToF measurement techniques used in three-dimensional modelling of cultural heritages. These measurement techniques are traditional photogrammetry, SfM approach, laser scanning and time-of-flight camera. The computer based approach to photogrammetric measurement that is named SfM creates dense point cloud data in a short time. It is low-cost and very easy to application. However traditional photogrammetry needs a huge effort for creating 3D wire-frame model. On the other hand active measurement techniques such as terrestrial laser scanner and time-of-flight camera have also been used in three-dimensional modelling for more than twenty years. Each one has specific accuracy and measurement effectiveness. The large or small structures have different characters, and require proper measurement configurations. In this study, after these methods are introduced, their superior and weak properties in cultural heritage modelling to make high accuracy, high density and labour and cost effective measurement.
HBIM MODELLING FOR AN HISTORICAL URBAN CENTRE
Authors: Avena M. , Colucci E. , Sammartano G. , Spanò A.
Published: June 2021

Abstract. The research in the geospatial data structuring and formats interoperability direction is the crucial task for creating a 3D Geodatabase at the urban scale. Both geometric and semantic data structuring should be considered, mainly regarding the interoperability of objects and formats generated outside the geographical space. Current reflections on 3D database generation, based on geospatial data, are mostly related to visualisation issues and context-related application. The purposes and scale of representation according to LoDs require some reflections, particularly for the transmission of semantic information.This contribution adopts and develops the integration of some tools to derive object-oriented modelling in the HBIM environment, both at the urban and architectural scale, from point clouds obtained by UAV (Unmanned Aerial Vehicle) photogrammetry.One of the paper’s objectives is retracing the analysis phases of the point clouds acquired by UAV photogrammetry technique and their suitability for multiscale modelling. Starting from UAV clouds, through the optimisation and segmentation, the proposed workflow tries to trigger the modelling of the objects according to the LODs, comparing the one coming from CityGML and the one in use in the BIM community. The experimentation proposed is focused on the case study of the city of Norcia, which like many other historic centres spread over the territory of central Italy, was deeply damaged by the 2016-17 earthquake.
THE RELIABILITY ASSESSMENT OF THE TLS REGISTRATION METHODS – THE CASE STUDY OF THE ROYAL CASTLE IN WARSAW
Authors: Markiewicz J. , Łapiński S. , Bocheńska A. , Kot P.
Published: June 2021

Abstract. Modern measurement technologies are commonly applied to monitor and preserve the cultural heritage as it is an integral part of modern societies. The Terrestrial Laser Scanning (TLS) method is one of the common technologies investigated by the researchers for accurate data acquisition and processing required for architectural documentation. In recent years, many methods were developed for TLS data registration to improve the processing time and accuracy of the bundle adjustment. The aim of this research is to compare the existing TLS target-based registration methods and compare them with the proposed novel method based on the reliability assessment- the robustness analysis. The novel feature-based approach also includes 2D detectors, which were applied to the TLS data converted into spherical images. Measurements were carried out at the Royal Castle in Warsaw using TLS Z+F 5006H and total station Leica TCRP1202. The collected data was analysed using existing software Z+F LaserControl, LupoScan and developed the application to perform 2D + 1H / 3D registration. The main results demonstrated that the proposed method for TLS registration removed the outliers that could not be eliminated by the deviation analysis on control and check points. The accuracy of TLS registration increased with a RMSE difference between 0.1 mm and 3.7 mm in comparison to existing methods. Furthermore, the accuracy of the results from 2D detectors was improved with relative orientation RMSE ≤ 2.1 mm and equivalent for control and check points for X, Y, and Z coordinates in comparison to target-based registration.
EVALUATION OF MACHINE LEARNING CLASSIFIERS FOR MAPPING FALCATA PLANTATIONS IN SENTINEL-2 IMAGE
Authors: Santillan J. R. , Gesta J. L. E.
Published: June 2021

Abstract. Efficient and accurate mapping of forest and other industrial tree plantations (ITPs) is essential to ensure better monitoring and sustainable management of these plantations. In Caraga Region, Mindanao, Philippines, ITPs planted with Falcata (Paraserianthes falcataria (L.) Nielsen) are widespread and has contributed to more than 50% of the nationwide log production. At present, there is limited information on the location and extent of existing plantations. This provides an opportunity to evaluate satellite remote sensing approaches for mapping these plantations from images, particularly those provided by the Sentinel-2 mission. The objective of this study is to evaluate machine learning classifiers for mapping Falcata plantations in Sentinel-2 image using a 9 × 9 km2 study area in Caraga Region. It also aims to find the best classifier that can provide acceptable levels of accuracy by utilizing only the four bands of the 10-m spatial resolution and the 9 bands of the 20-m spatial resolution Level 2A Sentinel-2 image, respectively. The following classifiers and their variants were evaluated: Linear Support Vector Machine (SVM), Polynomial SVM, Radial Basis Function (RBF) SVM, Artificial Neural Network (Neural Net), Random Forest (RF), and Maximum Likelihood (ML). One or more of these classifiers have been successfully used in in natural and plantation forest mapping, including tree species classification from remotely sensed images. However, their performance and accuracy in detecting and discriminating Falcata plantations is yet to be evaluated. Results of the evaluation showed that the ML classifier has the highest overall accuracy (OA) of 90.90% and has more consistent values for Producer’s Accuracy (PA), and User’s Accuracy (UA) for Falcata and Non-Falcata classes, and hence, provides better Falcata classification results than the other classifiers when the 10-m spatial resolution Sentinel-2 image was used. The accuracy assessment of the 20-m subset classification provides relative different results from that of the 10-m subset, perhaps due to the inclusion of more bands. The highest OA was obtained by the Linear and RBF SVM classifiers at 92.05% each. The SVM classifiers have consistent performance and produce more accurate classification results than the other classifiers (i.e., more than 90% OA, PA, and UA). From these results, it can be concluded that Maximum Likelihood classifier is best to use for Falcata mapping using the 10-m spatial resolution Sentinel-2 image. For the 20-m resolution image, any of the two SVMs (linear or RBF) is more appropriate to use. However, it should be noted that these results are based on classifications where default parameters were used. Improvement in the classification accuracy may be achieved if these parameters were optimized.
GROUNDWATER MONITORING USING GRACE MISSION
Authors: Shukla M. , Maurya V. , Dwivedi R.
Published: June 2021

Abstract. Since last few decades, India has met to major crises related to groundwater. Major cities, for example, Delhi, Chennai, Bengaluru etc. are facing extreme risk of water crisis. In next few decades, this may lead to a major water crisis when this non-renewable resource is exhausted. Gravity Recovery and Climate Experiment (GRACE) mission, widely used for monitoring of groundwater storage change, could be utilized to get the information of exact amount of water above or below the surface of the earth that may be used to counter act over such situation of water crisis. GRACE mission consists of two earth orbiting satellite vehicles (SVs) separated by 220 km with the objective of computing change in gravity by increasing or decreasing distance between both the SVs caused by higher or lower gravity masses. The primary objective of the presented work is to obtain the liquid water equivalent height in a selected area using GRACE mission data with GLDAS soil moisture data. The advantage of using GRACE is that it provides better accuracy (fraction of 1cm) in comparison to traditional methods, therefore, larger extent could be covered. This paper extensively discusses about GRACE application (especially groundwater monitoring), challenges with GRACE missions and about effective methods for groundwater recharge.
ICE FLOW VELOCITY MAPPING IN EAST ANTARCTICA USING HISTORICAL IMAGES FROM 1960s TO 1980s: RECENT PROGRESS
Authors: Luo S. , Cheng Y. , Li Z. , Wang Y. , Wang K. , Wang X. , Qiao G. , Ye W. , Li Y. , Xia M. , Yuan X. , Tian Y. , Tong X. , Li R.
Published: June 2021

Abstract. Recent research indicates that the estimated elevation changes and associated mass balance in East Antarctica are of some degree of uncertainty; a light accumulation has occurred in its vast inland regions, while mass loss in Wilkes Land appears significant. It is necessary to study the mass change trend in the context of a long period of the East Antarctic Ice Sheet (EAIS). The input-output method based on surface ice flow velocity and ice thickness is one of the most important ways to estimate the mass balance, which can provide longer-term knowledge of mass balance because of the availability of the early satellites in 1960s. In this study, we briefly describe the method of extracting ice velocity based on the historical optical images from 1960s to 1980s. Based on the draft ice velocity map of the EAIS using this method, we conduct a series of validation experiments, including comparisons with in-situ measurement, existing historical maps and rock outcrop dataset. Finally, we use the input-output method to estimate mass balance in some regions of EAIS using the generated velocity map.
UPSCALING AND VALIDATION OF RTK-DIRECT GEOREFERENCED UAV-BASED RGB IMAGE DATA WITH PLANET IMAGERY USING POLYGON GRIDS FOR PASTURE MONITORING
Authors: Bareth G. , Hütt C.
Published: June 2021

Abstract. The monitoring of managed grasslands with remote sensing methods is becoming more important for spatial decision support. Various remote sensing data acquisition techniques are applied for that purpose in different spatial resolutions ranging from UAV-borne to satellite-based remote sensing. In the last decade, UAV-borne imaging and analysis techniques or in the focus of crop and grassland monitoring and provide very high spatial resolutions. In contrast, satellite data are only available in high to moderate spatial resolutions. In this contribution, we introduce direct georeferenced data acquisition with a Phantom 4 RTK for pasture monitoring and investigate the upscaling of the cm data to satellite resolutions using polygon grids.
DEEP LEARNING BASED ROOF TYPE CLASSIFICATION USING VERY HIGH RESOLUTION AERIAL IMAGERY
Authors: Buyukdemircioglu M. , Can R. , Kocaman S.
Published: June 2021

Abstract. Automatic detection, segmentation and reconstruction of buildings in urban areas from Earth Observation (EO) data are still challenging for many researchers. Roof is one of the most important element in a building model. The three-dimensional geographical information system (3D GIS) applications generally require the roof type and roof geometry for performing various analyses on the models, such as energy efficiency. The conventional segmentation and classification methods are often based on features like corners, edges and line segments. In parallel to the developments in computer hardware and artificial intelligence (AI) methods including deep learning (DL), image features can be extracted automatically. As a DL technique, convolutional neural networks (CNNs) can also be used for image classification tasks, but require large amount of high quality training data for obtaining accurate results. The main aim of this study was to generate a roof type dataset from very high-resolution (10 cm) orthophotos of Cesme, Turkey, and to classify the roof types using a shallow CNN architecture. The training dataset consists 10,000 roof images and their labels. Six roof type classes such as flat, hip, half-hip, gable, pyramid and complex roofs were used for the classification in the study area. The prediction performance of the shallow CNN model used here was compared with the results obtained from the fine-tuning of three well-known pre-trained networks, i.e. VGG-16, EfficientNetB4, ResNet-50. The results show that although our CNN has slightly lower performance expressed with the overall accuracy, it is still acceptable for many applications using sparse data.
Glacial lake outburst flood hazard under current and future conditions: first insights from a transboundary Himalayan basin
Authors: Allen Simon , Sattar Ashim , King Owen , Zhang Guoqing , Bhattacharya Atanu , Yao Tandong , Bolch Tobias
Published: June 2021

Abstract. Glacial lake outburst floods (GLOFs) are a major concern throughout High Mountain Asia, where impacts can be far-reaching. This is particularly true for transboundary Himalayan basins, where risks are expected to further increase as new lakes develop. Given the need for anticipatory approaches to disaster risk reduction, this study aims to demonstrate how the threat from a future lake can be feasibly assessed along-side that of current lakes, and how this information can feed practically into decision-making and response planning. We have focused on two well-known dangerous lakes (Galongco and Jialongco), comparing the consequences of simulated worst-case outburst events from these lakes both in the Tibetan town of Nyalam and downstream at the border with Nepal. In addition, a future scenario has been assessed, whereby an outburst was simulated for a potential new lake forming upstream of Nyalam. Results show that although smallest in size, Jialongco, poses the greatest immediate threat to Nyalam and downstream communities, owing to the high potential for an ice avalanche to trigger an outburst. The future lake scenario would lead to flow depths and velocities that exceed either of the current scenarios, and the peak flood would reach Nepal up to 20 minutes faster. Based on these findings, a comprehensive approach to disaster risk reduction is called for, combining early warning systems with effective land use zoning and capacity building programs. Such approaches address the current drivers of GLOF risk in the basin, while remaining robust in the face of future emerging threats.
Continental-scale controls on soil organic carbon across sub-Saharan Africa
Authors: von Fromm Sophie F. , Hoyt Alison M. , Lange Markus , Acquah Gifty E. , Aynekulu Ermias , Berhe Asmeret Asefaw , Haefele Stephan M. , McGrath Steve P. , Shepherd Keith D. , Sila Andrew M. , Six Johan , Towett Erick K. , Trumbore Susan E. , Vågen Tor-G. , Weullow Elvis , Winowiecki Leigh A. , Doetterl Sebastian
Published: June 2021

Abstract. Soil organic carbon (SOC) stabilization and destabilization has been studied intensively. Yet, the factors which control SOC content across scales remain unclear. Earlier studies demonstrated that soil texture and geochemistry strongly affect SOC content. However, those findings primarily rely on data from temperate regions where soil mineralogy, weathering status and climatic conditions generally differ from tropical and subtropical regions. We investigated soil properties and climate variables influencing SOC concentrations across sub-Saharan Africa. A total of 1601 samples were analyzed, collected from two depths (0–20 and 20–50 cm) from 17 countries as part of the Africa Soil Information Service project (AfSIS). The data set spans arid to humid climates and includes soils with a wide range of pH values, weathering status, soil texture, exchangeable cations, extractable metals and land cover types. The most important SOC predictors were identified by linear mixed-effects models, regression trees and random forest models. Our results indicate that geochemical properties, mainly oxalate-extractable metals (Al and Fe) and exchangeable Ca, are equally important compared to climatic variables (mean annual temperature and aridity index). Together, they explain approximately two-thirds of SOC variation across sub-Saharan Africa. Oxalate-extractable metals were most important in wet regions with acidic and highly weathered soils, whereas exchangeable Ca was more important in alkaline and less weathered soils in drier regions. In contrast, land cover and soil texture were not significant SOC predictors on this large scale. Our findings indicate that key factors controlling SOC across sub-Saharan Africa are broadly similar to those in temperate regions, despite differences in soil development history.
Redentores de almas ante la Real Hacienda.
Authors: Bosco Michele
Published: June 2021

El artículo se enmarca en el dinámico debate sobre la esclavitud y la economía del rescate de cautivos en el Mediterráneo de la época moderna, y analiza la actividad redentora protagonizada por los frailes de la Orden de Nuestra Señora de la Merced, su labor de rescate de cautivos y la financiación y desarrollo de las misiones de redención en la larga duración (un siglo y medio aproximadamente). El ensayo se centra, en particular, en el estudio de cuatro misiones de redenciones (1575, 1612, 1678 y 1723) a través del análisis de los respectivos libros de cuentas, donde un notario real registraba todo movimiento de dinero, tanto de ingresos como de gastos, con el fin de permitir la trazabilidad y de tener bajo control la contabilidad de la actividad de rescate llevada a cabo por los religiosos. Como se verá, era la propia Monarquía hispánica que decidía a quiénes rescatar prioritariamente, y cuánto dinero emplear en ello, lo que limitaba mucho la libertad de acción de los religiosos redentores.
Management of retroperitoneal hematoma
Authors: Khudair Ayad Y.
Published: June 2021

Retroperitoneal traumatic lesions are among the most challenging and serious emergencies, and necessitate a maximum of attention and expertise by the surgical team involved. Only with a careful judgment about the procedures to carry on it is possible to obtain valid results, which often means to safe the patients life. This is a prospective study, which included 30 patients with traumatic retroperitoneal hematoma, admitted to AL-Hussien Teaching Hospital for the period between Dec. 2017 – Nov. 2019 (22 months). They were analyzed regarding age, sex, type of trauma, signs and symptoms, relevant laboratory tests and radiological studies, operative findings, associated organ injured, methods of treatment, postoperative complications and their mortality rate. Most patients were males (77.2%). Young age group was more frequently injured (34.85%) of patients were in their third decade. Penetrating injury was the cause in majority of collected patients (83.3%). The commonest zone of retroperitoneal hematoma was zone 2 (74.24%) and the commonest site was the lateral perirenal hematoma. In conclusion; the presence of lesions on the retroperitoneum generally worsens the prognosis in traumatic pathology. All types of trauma, blunt or open, may involve retroperitoneal structures and organs. Associated abdominal organs injury may include the great vessels, pancreas, duodenum, oesophagus and genitourinary apparatus.
Extradition Law and Procedure in Pakistan: An Appraisal of the Extradition Act 1972
Authors: Rafay Bukhari Syed Wajdan ,   Law College University of Sargodha, Sargodha, Pakistan, Abbas Dr Aamir
Published: June 2021

This article analyses the law and procedure of extradition in Pakistan with special reference to Extradition Act 1972. Extradition is a surrender of an accused or convicted person from one state to other state on its request. It is also considered as a system by which one state delivers an accused person to another state on her demand. Moreover, extradition is also used as a tool and considered to be one of the stages to secure international criminal justice system. Furthermore, the focus of the study is to discuss the interpretation of Extradition Act 1972 by the superior courts in their decisions. This study reveals that there are some lacunas in Extradition Act 1972 i.e., there is no provision which safeguards the fugitive offenders from cruel, torture and other inhumane treatment in the requesting state, it does not guarantee the fair trial of the offender in demanding state, additionally, this Act does not provide any right of appeal against the order of surrender. Resultantly, this paper finds that Extradition Act 1972 provide less safeguard to the fugitive offender and did not guarantee the fair trial in the requesting state.
Gender Diversity in Corporate Boards: A Comparative Study of Pakistan and Norway
Authors: Asghar Tayyaba Noor
Published: June 2021

With the increased attention given to corporate governance, there has been more focus on the lack of gender diversity in corporate boards. Within the context of corporate governance, this research focuses on the gender diversity in the boardrooms and to evaluate how the percentage of female directors on a company’s board affects the firm’s performance. For this purpose, Gender diversity in both Norway and in the Pakistan are studied, but this study more focuses on the Pakistan’s board gender diversity, legislations, implementation and its impact on company’s performance, this study also focuses on Norwegian experience and the impact of the Norwegian gender diversity rule. This study is conducted by a qualitative research and a socio-legal research methodology due to library based and its mixed nature of being legal and corporate respectively. This study is also based on primary as well as secondary sources. The results of this study show that there is observable performance benefit to adding more females to the board of directors. Companies found a significant and positive relationship between the percentage of women on the board and performance. These results suggest that if Pakistan decides to adopt strong legislation for corporations in relation to gender diversity and implement them; it will observe significant improvement in firm performance.
THE REQUISITION OF AUTO SYNCHRONISM FOR VACUUM INTERRUPTERS DURING QUENCHING ARC INTERVAL
Authors: SHEMSHADI A. , JALALI KASHANI S.
Published: June 2021

This investigation presents new practical-based achievements for velocity of dielectric recovery process lead to successful quenching arc inside a vacuum interrupter (VI) chamber related to arcing interval duration with utilization of thermionic emission theory. A high voltage impulse is applied to the contacts of a vacuum interrupter to cause insulation failure during quenching arc interval with utilization of new high-speed spark gap switch concerning 4 mm contact distance. Regarding to left branch of paschen's curve the achieved results are admissible. But for some data with equal H.V. pulse time, it was observed that the breakdown voltage level, for similar quenching time, may differ regarding to arcing time duration. Longer the arcing time results stiffer insulation recovery process. In addition, more arcing time results to more corrosion in contacts. These truths demonstrate the requisition of designing a synchronous observer system to control the moment of mechanical opening process regarding to quenching sinusoidal current waveform. This system should continuously analyze and predict the next zero-crossing of the current waveform to trigger the mechanical opening mechanism after last peak of the flowing current.
GYROTACTIC MICROORGANISMS FREE CONVECTION BOUNDARY LAYER FLOW ABOUT A VERTICAL TRUNCATED CONE IN NANOFLUID POROUS MEDIA
Authors: MAHDY A. , ELSHEHABEY H. M.
Published: June 2021

A non-similar boundary layer analysis is presented to examine the natural convection flow over a truncated cone with fixed apex half angle; pointing downwards in a nanofluid saturated porous medium contains gyrotactic microorganisms. A suitable coordinate transformation is performed, and the obtained non-similar equations are solved by fourth order Runge–Kutta method technique coupled with shooting scheme. The effects of the thermophoresis parameter, Brownian parameter, Lewis number, bioconvection Peclet number, bioconvection Lewis number, bioconvection Rayleigh number and buoyancy ratio on the reduced Nusselt, Sherwood and density of motile microorganisms numbers have been studied. A comprehensive numerical computation is carried out for various values of the parameters that describe the flow characteristics.
Motivation in Foreign Language Classrooms at Tertiary Level: A Case Study
Authors: Khau Anh Hoang , Thach La Pho
Published: June 2021

In teaching and learning a foreign language, especially English, motivation plays an extremely integral part in ensuring success. In this study, the researchers attempt to provide an overview of research on motivation and discover how motivation can assist second or foreign language learning in classrooms of English-majored students in the university setting. This study aims to investigate whether English-majored learners are motivated in learning English or not, focusing on extrinsic motivational factors to identify the factors to develop their motivation and maintain their journey of learning English. A questionnaire is devised and administered to 52 senior English-majored students. The data was then analyzed using the SPSS version 20. The results suggest that learners’ motivation is related to learning facilities and teacher’s personality which can encourage learners to think more positively and thus be more motivated in their language learning process. Along with providing specific recommendations for further research on motivation, the paper concludes by calling on for adopting a range of motivational factors that can promote English as a foreign or second language learning.
An Investigation into Secondary School Students’ Sino-Vietnamese Competence in Philology Learning Activities
Authors: Trinh Lan Thi , Nguyen Tu Cam Thi , Nguyen Anh Ngoc Thi
Published: June 2021

Sino-Vietnamese vocabulary is an important part of Vietnamese vocabulary. The ability to use Sino-Vietnamese vocabulary partially reflects one’s Vietnamese language competence; therefore, the ability to use Sino-Vietnamese vocabulary is an important element in the language ability of Vietnamese people in general, and secondary school students in particular. During in-class literature activities, secondary school students are equipped with Sino-Vietnamese vocabulary to a certain extent, but the effectiveness of using Sino-Vietnamese vocabulary in communication and in learning has yet to be fully evaluated. This article focuses on evaluating the ability to use Sino-Vietnamese vocabulary of secondary school students in Hanoi by using questionnaires and tests to obtain both subjective and objective data from the learner’s perspective. The survey results will be used as a practical premise to propose new teaching methods to develop Sino-Vietnamese language competence of secondary school students in Literature, in accordance with the 2018 General Education Curriculum.
HARMONIOUS PHYSICAL DEVELOPMENT STUDY OF FIRST GRADE PUPILS
Authors:   ", Urichianu Bogdan Andrei ,   Carol Davila",   University of Medicine and Pharmacy, Romania, Vischiu Cristina ,   Theoretical High School ”Mihail Sadoveanu”, Republic of Moldova
Published: June 2021

The harmony of the physical body development of human beings and working constantly since antiquity, became part of the educational ideal in Greece (KALOSKAGATHON - Nice man and good) or the Roman baths. (Mens sana in corpore sano - Juvenal). In this study we aimed to accomplish finding harmonious physical development of students in preparatory class at Secondary School No. 16 in Bucharest. Objectives of the study is to determine the factors that influence the physical, cognitive and psycho social development of 6-7 years pupils. The methods used in this study are: the literature, teaching observation, measurement method, statistical and mathematical methods of data processing and interpretation. Observations and measurements carried out proves that the psychological and physical development of students are below the required values corresponding to their age which shows lack of physical activity practice by not participating actively in physical education lessons and the lack of games and recreational activities in free time. In a study conducted we have concluded that the introduction of three hours of physical education, as required by law, it is imperative that all pupils benefit from a harmonious physical development. Moreover families and schools are responsible for pupils' participation in physical activity, especially in the form of age-specific play.