Publications by authors named "Tim Kempen"

Article Synopsis
  • Resistive Random Access Memory (RRAM) is being researched for its benefits in energy efficiency and non-volatility, but designing effective systems is complex and time-consuming for material and device scientists.
  • There's a need for a user-friendly modeling framework that helps researchers evaluate device performance early in the design process, focusing on speed, accuracy, and adaptability.
  • This paper presents a digital twin (DT)-like framework that generates RRAM device models from measurement data, includes peripheral circuits for better evaluations, and demonstrates its effectiveness in applications like neural network processing of ECG data and Fault Aware Training.
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As atmospheric methane concentrations increase at record pace, it is critical to identify individual emission sources with high potential for mitigation. Here, we leverage the synergy between satellite instruments with different spatiotemporal coverage and resolution to detect and quantify emissions from individual landfills. We use the global surveying Tropospheric Monitoring Instrument (TROPOMI) to identify large emission hot spots and then zoom in with high-resolution target-mode observations from the GHGSat instrument suite to identify the responsible facilities and characterize their emissions.

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Southeast Australia experienced intensive and geographically extensive wildfires during the 2019-2020 summer season. The fires released substantial amounts of carbon dioxide into the atmosphere. However, existing emission estimates based on fire inventories are uncertain, and vary by up to a factor of four for this event.

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Methane emissions due to accidents in the oil and natural gas sector are very challenging to monitor, and hence are seldom considered in emission inventories and reporting. One of the main reasons is the lack of measurements during such events. Here we report the detection of large methane emissions from a gas well blowout in Ohio during February to March 2018 in the total column methane measurements from the spaceborne Tropospheric Monitoring Instrument (TROPOMI).

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Bioprinting is the most convenient microfabrication method to create biomimetic three-dimensional (3D) cardiac tissue constructs, which can be used to regenerate damaged tissue and provide platforms for drug screening. However, existing bioinks, which are usually composed of polymeric biomaterials, are poorly conductive and delay efficient electrical coupling between adjacent cardiac cells. To solve this problem, we developed a gold nanorod (GNR) incorporated gelatin methacryloyl (GelMA)-based bioink for printing 3D functional cardiac tissue constructs.

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The statistics of discovered exoplanets suggest that planets form efficiently. However, there are fundamental unsolved problems, such as excessive inward drift of particles in protoplanetary disks during planet formation. Recent theories invoke dust traps to overcome this problem.

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