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Improving global digital elevation models using space-borne GEDI and ICESat-2 LiDAR altimetry data

Narin, O.G. (author), Abdikan, Saygin (author), Gullu, Mevlut (author), Lindenbergh, R.C. (author), Balik Sanli, Fusun (author), Yilmaz, Ibrahim (author)

Open source Global Digital Elevation Models (GDEMs) serve as an important base for studies in geosciences. However, these models contain vertical errors due to various reasons. In this study, data from two Satellite LiDAR altimetry systems, GEDI and ICESat-2, were used to improve the vertical accuracy of GDEMs. Three different machine learning...

journal article 2024

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Steering the product spectrum in high-pressure anaerobic processes: CO₂ partial pressure as a novel tool in biorefinery concepts

Ceron Chafla, P.S. (author), de Vrieze, Jo (author), Rabaey, Korneel (author), van Lier, J.B. (author), Lindeboom, R.E.F. (author)

Background: Elevated CO₂ partial pressure (pCO₂) has been proposed as a potential steering parameter for selective carboxylate production in mixed culture fermentation. It is anticipated that intermediate product spectrum and production rates, as well as changes in the microbial community, are (in)directly influenced by...

journal article 2023

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Automatically Create Digital Elevation Model from Photos Captured by a Low-Cost UAV-Based System

Nguyen, Kiet Tuan (author), Phan, Anh Thu Thi (author), Truong-Hong, Linh (author)

Unmanned aerial vehicles (UAVs) are commonly utilized as cost-effective devices for data collection by capturing photos of target objects. UAV images have been used for many applications, such as civil engineering, transportation, architecture, surveying, and mapping. Although commercial UAV image data processing software is suitable for...

conference paper 2023

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Multi-Criteria Strategy for Estimating GEDI Terrain Height

Narin, O.G. (author), Lindenbergh, R.C. (author), Abdikan, S. (author)

Global Ecosystem Dynamics Investigate (GEDI) is a spaceborne laser altimeter system used for earth observation in many areas such as forest canopy, water level and terrain height estimation. GEDI data is affected by atmospheric effects due to the sensor used while observing. In this study, we propose a 7-step, multi-variable strategy for...

conference paper 2023

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A comparison of vertical accuracy of global DEMs and DEMs produced by GEDI, ICESat-2

Narin, O.G. (author), Gullu, Mevlut (author)

Digital elevation models (DEM) are an essential data source in many professional disciplines, with the help of gridded height information and values such as slope and aspect produced from that information. In this study, Ice, Cloud and land Elevation Satellite-2 (ICESat-2) and Global Ecosystem Dynamics Investigation (GEDI) satellite-altimetry...

journal article 2023

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Analysing the elevation-distributed hydro-climatic regime of the snow covered and glacierised Hunza Basin in the upper Indus

Nazeer, A. (author), Maskey, Shreedhar (author), Skaugen, Thomas (author), McClain, M.E. (author)

In the high altitude Hindukush Karakoram Himalaya (HKH) mountains, the complex weather system, inaccessible terrain and sparse measurements make the elevation-distributed precipitation and temperature among the most significant unknowns. The elevation-distributed snow and glacier dynamics in the HKH region are also little known, leading to...

journal article 2023

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Retrieval of forest height information using spaceborne LiDAR data: a comparison of GEDI and ICESat-2 missions for Crimean pine (Pinus nigra) stands

Vatandaslar, Can (author), Narin, O.G. (author), Abdikan, Saygin (author)

Key message: Despite showing a cost-effective potential for quantifying vertical forest structure, the GEDI and ICESat-2 satellite LiDAR missions fall short of the data accuracy standards required by tree- and stand-level forest inventories. Abstract: Tree and stand heights are key inventory variables in forestry, but measuring them manually...

journal article 2022

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Rapid Surface Large-Change Monitoring by Repeat-Pass GEO SAR Multibaseline Interferometry

Li, Y. (author), Hu, Cheng (author), Ao, Dongyang (author)

Fast observations of rapid surface large-changes are demanded in disaster evaluations and scientific studies. Digital elevation model (DEM) differencing before and after the events is an effective way to retrieve the changes. Owing to a short repeat cycle, geosynchronous synthetic aperture radar (GEO SAR) systems can quickly obtain repeat...

journal article 2022

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Tomographic SAR imaging with large elevation aperture: a P-band small UAV demonstration

Zeng, Tao (author), Liu, Minkun (author), Wang, Yan (author), Ding, Zegang (author), Li, Linghao (author), Wang, Zhen (author), Wei, Yangkai (author), Wang, J. (author)

Elevation resolution is an important indicator in tomographic SAR imaging as it represents the ability to discriminate closed targets in elevation. In general, the elevation resolution is proportional to the length of the elevation aperture. However, as the elevation aperture increases, the geometric consistency of the image will undesirably...

journal article 2022

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Boosted robustness of semi-implicit subgrid methods for shallow water flash floods in hills

Stelling, G.S. (author)

The widespread availability of high-resolution Digital Elevation Models (DEM), has led to the development of subgrid numerical modeling techniques, based on Shallow Water Equations (SWE). Detailed DEM data is clustered as much as possible within a coarse grid cell that is preferably much larger than a raster pixel. This has considerable...

journal article 2022

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The effect of furnace steel slag powder on the performance of cementitious mortar at ambient temperature and after exposure to elevated temperatures

Miah, Md Jihad (author), Ali, Md Kawsar (author), Lo Monte, Francesco (author), Chandra Paul, Suvash (author), Babafemi, Adewumi John (author), Šavija, B. (author)

Induction furnace steel slag is a secondary product obtained when molten steel is separated from the impurities in the steel-producing furnaces. Though numerous studies have been published on the mechanical strength of concrete/mortar made with steel slag as fine aggregate, relatively few studies focus on the shrinkage, durability (i.e.,...

journal article 2021

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Directional Selection of Microbial Community Reduces Propionate Accumulation in Glycerol and Glucose Anaerobic Bioconversion Under Elevated pCO₂

Ceron Chafla, P.S. (author), Chang, Yu Ting (author), Rabaey, Korneel (author), van Lier, J.B. (author), Lindeboom, R.E.F. (author)

Volatile fatty acid accumulation is a sign of digester perturbation. Previous work showed the thermodynamic limitations of hydrogen and CO₂ in syntrophic propionate oxidation under elevated partial pressure of CO₂ (pCO₂). Here we study the effect of directional selection under increasing substrate load as a...

journal article 2021

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Combined effects of elevated temperatures and high strain rates on compressive performance of S30408 austenitic stainless steel

Li, Lijun (author), Wang, Rui (author), Zhao, Hui (author), Zhang, Haoran (author), Yan, R. (author)

This paper presents an experimental investigation on the dynamic mechanical performance of S30408 austenitic stainless steel (ASS) under elevated temperatures, which is essential for determining the behaviour of structures made with this type of steel subjected to the coupled fire and impact/explosion. For this purpose, the quasi-static and...

journal article 2021

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Salt marsh establishment in poorly consolidated muddy systems: effects of surface drainage, elevation, and plant age

Cao, Haobing (author), Zhu, Zhenchang (author), van Belzen, Jim (author), Gourgue, Olivier (author), van de Koppel, J. (author), Temmerman, O. Stijn (author), Herman, P.M.J. (author), Zhang, Liquan (author), Yuan, Lin (author), Bouma, Tjeerd J. (author)

Conservation and restoration of salt marsh ecosystems are becoming increasingly important because of the many ecosystem services they provide. However, the processes controlling salt marsh establishment and persistence, especially on bare tidal flats in muddy areas, remain unclear. As muddy sediments typically experience a restriction of soil...

journal article 2021

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A rapid and high-precision mountain vertex extraction method based on hotspot analysis clustering and improved eight-connected extraction algorithms for digital elevation models

Zheng, Zhenqi (author), Xiao, Xiongwu (author), Zhong, Zhi Chao (author), Zang, Y. (author), Yang, Nan (author), Tu, Jianguang (author), Li, Deren (author)

Digital Elevation Model (DEM)-based mountain vertex extraction is one of the most useful DEM applications, providing important information to properly characterize topographic features. Current vertex-extraction techniques have considerable limitations, such as yielding low-accuracy results and generating false mountain vertices. To overcome...

journal article 2021

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Ultra Thin Composite Panel – An Exploratory Study on the Durability and Stiffness of a Composite Panel of Thin Glass and 3D printed Recycled PET

Saleh, Charbel Miled Nohra (author), Louter, P.C. (author), Turrin, M. (author)

This paper investigates the stiffness and the durability of a composite panel that consists of thin glass as outer layers and a 3D printed core element from recycled PET. Thin alumino-silicate glass, mostly used for displays in computers, tablets and smartphones, is known for its flexibility, durability and high bending strength. However, for...

conference paper 2020

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Acoustic emission based investigation on the effect of temperature and hybridization on drop weight impact and post-impact residual strength of hemp and basalt fibres reinforced polymer composite laminates

Suresh Kumar, C. (author), Fotouhi, Mohamad (author), Saeedifar, M. (author), Arumugam, V. (author)

This paper investigates the effect of temperature and hybridization on the impact damage evolution and post-impact residual strength of hemp/epoxy, basalt/epoxy and their hybrid laminates, using mechanical and acoustic emission (AE) based analysis. To start with, the specimens were impacted by a drop weight impact tower machine at two...

journal article 2019

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Commentary: The need for a high-accuracy, open-access global DEM

Winsemius, H.C. (author), Ward, Philip J. (author), Gayton, Ivan (author), ten Veldhuis, Marie-claire (author), Meijer, D.H. (author), Iliffe, Mark (author)

A Commentary on 'The Need for a High-Accuracy, Open-Access Global DEM' by Schumann, G. J.-P., and Bates, P. D. (2018). Front. Earth Sci. 6:225. doi: 10.3389/feart.2018.00225

journal article 2019

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Single-Epoch, Single-Frequency Multi-GNSS L5 RTK under High-Elevation Masking

Wang, Kan (author), Chen, Pei (author), Teunissen, P.J.G. (author)

The Japanese Quasi-Zenith Satellite System (QZSS) satellite system has placed in orbit four satellites by October 2017. The Indian Regional Navigation Satellite System (IRNSS) system has launched the new satellite IRNNSS-11 in April 2018, completing seven operational satellites. Together with the GPS block IIF satellites and the Galileo...

journal article 2019

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Adaptive, variable resolution grids for bathymetric applications using a quadtree approach

Toodesh, R. (author), Verhagen, S. (author)

The spatial sampling often used to process and represent bathymetric data are of fixed grid resolution where the least depth value is stored in each grid cell. This results in Digital Elevation Models (DEMs) that are used to depict the underlying features of the seafloor. With the discretion of the user, the resulting DEMs used may either be...

journal article 2018