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Imaging CO₂ reinjection into basalts at the CarbFix2 reinjection reservoir (Hellisheiði, Iceland) with body-wave seismic interferometry

Hassing, S.H.W. (author), Draganov, D.S. (author), Janssen, M.T.G. (author), Barnhoorn, A. (author), Wolf, K.H.A.A. (author), van den Berg, J.J. (author), Friebel, M. (author), van Otten, Gijs (author), Poletto, Flavio (author)

As part of the Synergetic Utilisation of CO (Formula presented.) storage Coupled with geothermal EnErgy Deployment project, investigating CO (Formula presented.) reinjection with different seismic methods, both passive and active seismic surveys have been conducted at the geothermal power plant at Hellisheiði, Iceland. During the 2021 survey,...

journal article 2024

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The Power of Characterizing Pore-Fluid Distribution for Microscopic CO2 Injection Studies in Tight Sandstones

Alkharraa, H.S.H. (author), Wolf, K.H.A.A. (author), AlQuraishi, Abdulrahman (author), Mahmoud, Mohamed (author), AlDuhailan, Mohammed (author), Zitha, P.L.J. (author)

The microscopic structure of low-permeability tight reservoirs is complicated due to diagenetic processes that impact the pore-fluid distribution and hydraulic properties of tight rocks. As part of an ongoing study of carbon dioxide-enhanced oil and gas recovery (CO2-EOR/EGR) and CO2 sequestration, this research article adopts an integrated...

journal article 2023

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Microscopic CO₂ Injection in Tight Rocks: Implications for Enhanced Oil Recovery and Carbon Geo-Storage

Alkharraa, H.S.H. (author), Wolf, K.H.A.A. (author), AlQuraishi, Abdulrahman (author), Al Abdrabalnabi, Ridha (author), Mahmoud, Mohamed (author), Zitha, P.L.J. (author)

Carbon dioxide (CO₂) injection has been widely used in conventional reservoirs for enhanced oil recovery and CO₂ sequestration. Nevertheless, the effectiveness of CO₂ injection in tight reservoirs is limited due to diagenetic processes that impact displacement efficiency. This research work assesses the...

journal article 2023

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Impact of clay mineralogy on the petrophysical properties of tight sandstones

Alkharraa, H.S.H. (author), Wolf, K.H.A.A. (author), AlQuraishi, Abdulrahman A. (author), Mahmoud, Mohamed A. (author), Deshenenkov, Ivan (author), AlDuhailan, Mohammed A. (author), Alarifi, Sulaiman A. (author), AlQahtani, Naif B. (author), Zitha, P.L.J. (author)

A full petrographic and petrophysical characterization of tight sandstones has been conducted as part of ongoing study of Carbon Dioxide Enhanced Oil and Gas Recovery (CO₂-EOR/EGR) and CO₂sequestration. The main purpose of this study is to give novel perception into the interplay of the rock characteristics and fluid...

journal article 2023

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Storing CO₂ in geothermal reservoir rocks from the Kizildere field, Turkey: Combined stress, temperature, and pore fluid dependence of seismic properties

Janssen, M.T.G. (author), Draganov, D.S. (author), Barnhoorn, A. (author), Wolf, K.H.A.A. (author)

As part of a seismic monitoring project in a geothermal field, where the feasibility of re-injection and storage of produced CO₂ is being investigated, a P- and S-wave seismic velocity characterisation study was carried out. The effect of axial and radial (up to 42 MPa) stress, pore pressure (up to 17 MPa), pore fluid (100% brine...

journal article 2023

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A Novel Technique to Estimate Water Saturation and Capillary Pressure of Foam in Model Fractures

Li, K. (author), Wolf, K.H.A.A. (author), Rossen, W.R. (author)

Foam is applied in enhanced oil recovery to improve the sweep of injected gas and increase oil recovery, by greatly reducing the mobility of gas. In the laboratory, X-ray computed tomography is commonly used to evaluate the performance of foam in core plugs. However, foam properties, such as bubble size and capillary pressure, are much more...

journal article 2022

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Deep Learning for Object Detection and Segmentation in Videos: Toward an Integration With Domain Knowledge

Ilioudi, A. (author), Dabiri, A. (author), Wolf, B.J. (author), De Schutter, B.H.K. (author)

Deep learning has enabled the rapid expansion of computer vision tasks from image frames to video segments. This paper focuses on the review of the latest research in the field of computer vision tasks in general and on object localization and identification of their associated pixels in video frames in particular. After performing a systematic...

journal article 2022

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Roadmap for edge AI: A Dagstuhl Perspective

Ding, Aaron Yi (author), Peltonen, Ella (author), Meuser, Tobias (author), Aral, Atakan (author), Becker, Christian (author), Dustdar, Schahram (author), Hiessl, Thomas (author), Kranzlmüller, Dieter (author), Liyanage, Madhusanka (author), Maghsudi, Setareh (author), Mohan, Nitinder (author), Ott, Jörg (author), Rellermeyer, Jan S. (author), Schulte, Stefan (author), Schulzrinne, Henning (author), Solmaz, Gürkan (author), Tarkoma, Sasu (author), Varghese, Blesson (author), Wolf, Lars (author)

Based on the collective input of Dagstuhl Seminar (21342), this paper presents a comprehensive discussion on AI methods and capabilities in the context of edge computing, referred as Edge AI. In a nutshell, we envision Edge AI to provide adaptation for data-driven applications, enhance network and radio access, and allow the creation,...

journal article 2022

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Evolution of helimagnetic correlations when approaching the quantum critical point of Mn1-xFexSi

Pappas, C. (author), Leonov, A.O. (author), Bannenberg, L.J. (author), Fouquet, P (author), Wolf, T. (author), Weber, F (author)

We present a comprehensive investigation of the evolution of helimagnetic correlations in Mn1−xFexSi with increasing doping. By combining polarized neutron scattering and high resolution neutron spin echo spectroscopy we investigate three samples with x = 0.09, 0.11, and 0.14, i.e., with compositions on both sides of the concentration x∗∼0.11...

journal article 2021

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Effects of Gas Trapping on Foam Mobility in a Model Fracture

Li, K. (author), Wolf, K.H.A.A. (author), Rossen, W.R. (author)

In enhanced oil recovery, foam can effectively mitigate conformance problems and maintain a stable displacement front, by trapping gas and reducing its relative permeability in situ. In this study, to understand gas trapping in fractures and how it affects foam behavior, we report foam experiments in a 1-m-long glass model fracture with a...

journal article 2021

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Coarsening of foam in two model fractures with different roughness

Li, K. (author), Sharifnik, Mohammadamin (author), Wolf, K.H.A.A. (author), Rossen, W.R. (author)

Foam coarsening by diffusion (Ostwald ripening) has been well studied in bulk foams. However, it is less well understood in porous media. In particular, the mechanisms that may slow or stop coarsening have not been fully investigated. In this paper, we report an experimental study of foam coarsening in two 1-m-long and 15-cm-wide model fractures...

journal article 2021

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Seismic velocity characterisation of geothermal reservoir rocks for CO₂ storage performance assessment

Janssen, M.T.G. (author), Barnhoorn, A. (author), Draganov, D.S. (author), Wolf, K.H.A.A. (author), Durucan, Sevket (author)

As part of a seismic monitoring project in a geothermal field, where the feasibility of re-injection and storage of produced CO₂ is being investigated, a P-and S-wave seismic velocity characterisation study was carried out. The effect of axial (up to 95 MPa) and radial (up to 60 MPa) stress on the seismic velocity was studied in...

journal article 2021

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The quadrature method: A novel dipole localisation algorithm for artificial lateral lines compared to state of the art

Bot, Daniël M. (author), Wolf, B.J. (author), van Netten, Sietse M. (author)

The lateral line organ of fish has inspired engineers to develop flow sensor arrays— dubbed artificial lateral lines (ALLs)—capable of detecting near-field hydrodynamic events for obstacle avoidance and object detection. In this paper, we present a comprehensive review and comparison of ten localisation algorithms for ALLs. Differences in the...

journal article 2021

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Effects of Gravity on Foam Behavior in Roughened Model Fractures

Li, K. (author), Wolf, K.H.A.A. (author), Rossen, W.R. (author)

In this study, to investigate how gravity affects foam in open vertical fractures, we report foam experiments in three 1-m-long, 15-cm-wide glass-model fractures. Each fracture has a smooth wall and a roughened wall. Between the two walls is a slit-like channel representing a single geological fracture. Three model fractures (Models A, B, and C)...

journal article 2021

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Multimodal imaging combining time-domain near-infrared optical tomography and continuous-wave fluorescence molecular tomography

Ren, Wuwei (author), Jiang, Jingjing (author), Di Costanzo Mata, Aldo (author), Kalyanov, Alexander (author), Ripoll, Jorge (author), Lindner, S.A. (author), Charbon-Iwasaki-Charbon, E. (author), Zhang, C. (author), Rudin, Markus (author), Wolf, Martin (author)

Fluorescence molecular tomography (FMT) emerges as a powerful non-invasive imaging tool with the ability to resolve fluorescence signals from sources located deep in living tissues. Yet, the accuracy of FMT reconstruction depends on the deviation of the assumed optical properties from the actual values. In this work, we improved the accuracy...

journal article 2020

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Advanced Infrared Thermography Data Analysis for Unsteady Boundary Layer Transition Detection

Mertens, C. (author), Wolf, C. Christian (author), Gardner, Anthony D. (author), Schrijer, F.F.J. (author), van Oudheusden, B.W. (author)

Advanced data processing methods for detecting unsteady boundary layer transition in periodic aerodynamic processes by means of infrared thermography measurements are presented. The thermal radiation emitted from the heated suction surface of a pitching airfoil model in subsonic flow is measured with an infrared camera. The unsteady boundary...

journal article 2020

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Foam generation by capillary snap-off in flow across a sharp permeability transition

Shah, Swej Y. (author), Wolf, K.H.A.A. (author), Pilus, Rashidah M. (author), Rossen, W.R. (author)

Foam reduces gas mobility and can improve sweep efficiency in an enhanced-oil-recovery (EOR) process. Previous studies show that foam can be generated in porous media by exceeding a critical velocity or pressure gradient. This requirement is typically met only near the wellbore, and it is uncertain whether foam can propagate several tens of...

journal article 2019

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A CMOS SPAD Imager with Collision Detection and 128 Dynamically Reallocating TDCs for Single-Photon Counting and 3D Time-of-Flight Imaging

Zhang, C. (author), Lindner, S.A. (author), Antolović, I.M. (author), Wolf, Martin (author), Charbon-Iwasaki-Charbon, E. (author)

Per-pixel time-to-digital converter (TDC) architectures have been exploited by single-photon avalanche diode (SPAD) sensors to achieve high photon throughput, but at the expense of fill factor, pixel pitch and readout efficiency. In contrast, TDC sharing architecture usually features high fill factor at small pixel pitch and energy efficient...

journal article 2018

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Proteomic analysis of methanonatronarchaeum thermophilum AMET1, a representative of a putative new class of euryarchaeota, “methanonatronarchaeia”

Ferrer, Manuel (author), Sorokin, Dimitry Y. (author), Wolf, Yuri I. (author), Ciordia, Sergio (author), Mena, María Carmen (author), Bargiela, Rafael (author), Koonin, Eugene V. (author), Makarova, Kira S. (author)

The recently discovered Methanonatronarchaeia are extremely halophilic and moderately thermophilic methyl-reducing methanogens representing a novel class-level lineage in the phylum Euryarchaeota related to the class Halobacteria. Here we present a detailed analysis of 1D-nano liquid chromatography–electrospray ionization tandem mass...

journal article 2018

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Discovery of extremely halophilic, methyl-reducing euryarchaea provides insights into the evolutionary origin of methanogenesis

Sorokin, Dimitry Y. (author), Makarova, Kira S. (author), Abbas, B.A. (author), Ferrer, Manuel (author), Golyshin, Peter N. (author), Galinski, Erwin A. (author), Ciordia, Sergio (author), Mena, María Carmen (author), Merkel, Alexander Y. (author), Wolf, Yuri I. (author), van Loosdrecht, Mark C.M. (author), Koonin, Eugene V. (author)

Methanogenic archaea are major players in the global carbon cycle and in the biotechnology of anaerobic digestion. The phylum Euryarchaeota includes diverse groups of methanogens that are interspersed with non-methanogenic lineages. So far, methanogens inhabiting hypersaline environments have been identified only within the order...

journal article 2017