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Analysis of Oil Stain Degradation on Asphalt Pavement in Tunnels Using Nanophotocatalytic Coatings
No full textIn enclosed tunnel environments with poor ventilation, vehicle emissions and spilled fuel (such as gasoline and diesel) accumulate on the road surface, forming oil stains that significantly impact both the environment and driving safety. To address this issue effectively, this study investigates the use of a nano-TiO2 coating for degrading road surface oil stains. Nano-TiO2 doped with Fe3+ and Fe3+-TiO2 supported by activated carbon were prepared using a sol-gel method. The materials were characterized using X-ray diffraction (XRD), UV-visible spectroscopy (UV-vis), and Fourier transform infrared spectroscopy (FTIR) to determine the crystal structure and properties of TiO2. The results showed that Fe3+ doping reduced the average particle size of TiO2 and significantly enhanced its catalytic activity. At the doping level of 0.5% Fe3+, the material achieved a degradation efficiency of 71.34% under UV light and 61.49% under normal light within 3 h. Although activated carbon did not noticeably affect particle size, its porous structure increased the photocatalytic reaction area, thus improving efficiency. Oil stain degradation tests further determined that a 0.5% Fe3+ doping level and 50% activated carbon loading yielded the best results. Additionally, the reusability of the material was verified through repeated degradation experiments
Exclusive optimization of Cs2AgBi0.75Sb0.25Br6-based solar cells using dual ETL with better photo transmission
No full textThe current study discusses an eco-friendly, sustainable, lead-free, perovskite-based solar cell architecture that enhances photoconversion efficiency. We selected caesium silver bismuth Antimony bromide (Cs2AgBi0.75Sb0.25Br6) as the absorber material due to its non-toxic properties, remarkable thermal and chemical stability, and compatibility with cost-effective solution-processing techniques. The photovoltaic characteristics of the Cs2AgBi0.75Sb0.25Br6 -based device are examined using SCAPS-1D solar simulation software. Additionally, we analyze the output characteristics for optimal thickness-defect, IF defects, and Series-Shunt resistances to achieve optimized performance. The output PV parameters of a dual ETL-based PSC device having the structure of ITO/AZO/Mxene + TiO2/Cs2AgBi0.75Sb0.25Br6/V2O5/Ag achieve maximum fill factors of 90.21%, as well as an outstanding 22.11% PCE, surpassing the performance of its kind, which is a significant growth in designing the perovskite solar cell. It can be noted that the overall device efficiency increases with lesser defects and lower thickness in the carrier transport layers. The work provides a detailed analysis of the Caesium-based PSC, which can be effective in inorganic-based solar devices with semi-transparent characteristics
Cheetah: Accelerating Dynamic Graph Mining with Grouping Updates
No full textGraph pattern mining is essential for deciphering complex networks. In the real world, graphs are dynamic and evolve over time, necessitating updates in mining patterns to reflect these changes. Traditional methods use fine-grained incremental computation to avoid full re-mining after each update, which improves speed but often overlooks potential gains from examining inter-update interactions holistically, thus missing out on overall efficiency improvements.In this article, we introduce Cheetah, a dynamic graph mining system that processes updates in a coarse-grained manner by leveraging exploration domains. These domains exploit the community structure of real-world graphs to uncover data reuse opportunities typically missed by existing approaches. Exploration domains, which encapsulate extensive portions of the graph relevant to updates, allow multiple updates to explore the same regions efficiently. Cheetah dynamically constructs these domains using a management module that identifies and maintains areas of redundancy as the graph changes. By grouping updates within these domains and employing a neighbor-centric expansion strategy, Cheetah minimizes redundant data accesses. Our evaluation of Cheetah across five real-world datasets shows it outperforms current leading systems by an average factor of 2.63×
Hourly Simulated Power Production Data with Snow Loss Model at Queued Utility-Scale PV Sites Simulated as Fixed-Tilt Systems in the U.S. Eastern Interconnection for Weather Year 2014
No full textUsing 2014 weather data, we ran PySAM power production simulations for utility-scale PV sites in the U.S. Eastern Interconnection queue. Site IDs, capacities, and locations (counties) were extracted from Lawrence Berkeley National Laboratory’s Queued Up: 2024 Edition dataset. No panel mount information was provided, so all sites were assumed to be 30-degree, fixed tilt systems. Sites’ latitudes and longitudes were assumed to be the centers of the installation counties. See queued_site_metadata.csv file for individual site metadata
Hourly Simulated Power Production Data with Snow Loss Model at Queued Utility-Scale PV Sites Simulated as Fixed-Tilt Systems in the U.S. Eastern Interconnection for Weather Year 2017
No full textUsing 2017 weather data, we ran PySAM power production simulations for utility-scale PV sites in the U.S. Eastern Interconnection queue. Site IDs, capacities, and locations (counties) were extracted from Lawrence Berkeley National Laboratory’s Queued Up: 2024 Edition dataset. No panel mount information was provided, so all sites were assumed to be 30-degree, fixed tilt systems. Sites’ latitudes and longitudes were assumed to be the centers of the installation counties. See queued_site_metadata.csv file for individual site metadata
Hourly Simulated Power Production Data with No Snow Loss Model at Queued Utility-Scale PV Sites Simulated as Fixed-Tilt Systems in the U.S. Eastern Interconnection for Weather Year 2013
No full textUsing 2013 weather data, we ran PySAM power production simulations for utility-scale PV sites in the U.S. Eastern Interconnection queue. Site IDs, capacities, and locations (counties) were extracted from Lawrence Berkeley National Laboratory’s Queued Up: 2024 Edition dataset. No panel mount information was provided, so all sites were assumed to be 30-degree, fixed tilt systems. Sites’ latitudes and longitudes were assumed to be the centers of the installation counties. See queued_site_metadata.csv file for individual site metadata
Hourly Simulated Power Production Data with No Snow Loss Model at Queued Utility-Scale PV Sites Simulated as Fixed-Tilt Systems in the U.S. Eastern Interconnection for Weather Year 2018
No full textUsing 2018 weather data, we ran PySAM power production simulations for utility-scale PV sites in the U.S. Eastern Interconnection queue. Site IDs, capacities, and locations (counties) were extracted from Lawrence Berkeley National Laboratory’s Queued Up: 2024 Edition dataset. No panel mount information was provided, so all sites were assumed to be 30-degree, fixed tilt systems. Sites’ latitudes and longitudes were assumed to be the centers of the installation counties. See queued_site_metadata.csv file for individual site metadata
Hourly Simulated Power Production Data with No Snow Loss Model at Queued Utility-Scale PV Sites Simulated as Fixed-Tilt Systems in the U.S. Eastern Interconnection for Weather Year 2019
No full textUsing 2019 weather data, we ran PySAM power production simulations for utility-scale PV sites in the U.S. Eastern Interconnection queue. Site IDs, capacities, and locations (counties) were extracted from Lawrence Berkeley National Laboratory’s Queued Up: 2024 Edition dataset. No panel mount information was provided, so all sites were assumed to be 30-degree, fixed tilt systems. Sites’ latitudes and longitudes were assumed to be the centers of the installation counties. See queued_site_metadata.csv file for individual site metadata
Scaler Rates from the Pierre Auger Observatory: A New Proxy of Solar Activity
No full textThe modulation of low-energy galactic cosmic rays reflects interplanetary magnetic field variations and can provide useful information on solar activity. An array of ground-surface detectors can reveal the secondary particles, which originate from the interaction of cosmic rays with the atmosphere. In this work, we present an investigation of the low-threshold rate (scaler) time series recorded in 16 yr of operation by the Pierre Auger Observatory surface detectors in Malargüe, Argentina. Through an advanced spectral analysis, we detected highly statistically significant variations in the time series with periods ranging from the decadal to the daily scale. We investigate their origin, revealing a direct connection with solar variability. Thanks to their intrinsic very low noise level, the Auger scalers allow a thorough and detailed investigation of the galactic cosmic-ray flux variations in the heliosphere at different timescales and can, therefore, be considered a new proxy of solar variability
Hourly Simulated Power Production Data with No Snow Loss Model at Queued Utility-Scale PV Sites Simulated as Single-Axis Tracking Systems in the U.S. Eastern Interconnection for Weather Year 2016
No full textUsing 2016 weather data, we ran PySAM power production simulations for utility-scale PV sites in the U.S. Eastern Interconnection queue. Site IDs, capacities, and locations (counties) were extracted from Lawrence Berkeley National Laboratory\u27s Queued Up: 2024 Edition dataset. No panel mount information was provided, so all sites were assumed to be the centers of the installation counties. See queued_site_metadata.csv file for individual site metadat