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De Eyckiaanse miniaturen in het Turijns-Milanees Getijdenboek
No full textCatalogue published on the occasion of the exhibition “Van Eyck. Een optische revolutie” Museum voor Schone Kunsten, Gent, 1 February-30 April 2020
Measurements and calculations of H2O broadened by CO2 collisional parameters for planetary atmospheres
Get PDFCollisional parameters of H2O with CO2 are currently missing from international spectroscopic databases, although they are essential for accurate modeling of water vapor in CO2-rich planetary atmospheres. In this study, high-resolution infrared spectra of H2O broadened by CO2 were recorded using a Fourier Transform Spectrometer in the 1.18 and 2.34 µm spectral regions. CO2-collisional parameters for selected H2O transitions were derived through a multispectrum fitting procedure employing both Voigt and quadratic speed-dependent Voigt profiles. Furthermore, calculations based on the semi-classical Complex Robert-Bonamy-Ma formalism were performed to estimate CO2-broadened half-widths, line shifts, and their temperature dependencies across various atmospheric transparency windows. It results in a strong agreement between theoretical predictions and experimental data. Finally, the shared calculated linelist, obtained for a wide range of transitions, can be directly applied to radiative transfer modeling of atmospheres primarily composed of carbon dioxide
Ground-based tropospheric ozone measurements: regional tropospheric ozone column trends from the TOAR-II/HEGIFTOM homogenized datasets
Get PDFQuantifying long-term free-tropospheric ozone trends is essential for understanding the impact of human activities and climate change on atmospheric chemistry. However, this is complicated by two key challenges: the differences among existing satellite-derived tropospheric ozone products, which are not yet fully understood or reconciled, and the limited temporal and spatial coverage of ground-based reference measurements. Here, we explore if a more consistent understanding of the geographical distribution of tropospheric ozone column (TrOC) trends can be obtained by focusing on regional trends from ground-based measurements. Regions were determined with a correlation analysis between modeled TrOCs at the site locations. For those regions, TrOC trends were estimated with quantile regression for the Trajectory-mapped Ozonesonde dataset for the Stratosphere and Troposphere (TOST) and with a linear mixed-effects modeling (LMM) approach to calculate synthesized trends from homogenized HEGIFTOM (Harmonization and Evaluation of Ground-based Instruments for Free-Tropospheric Ozone Measurements) individual site trends. For different periods (1990–2021/22, 1995–2021/22, 2000–2021/22), both approaches give increasing (partial) tropospheric ozone column amounts over almost all Asian regions (median confidence) and negative trends over Arctic regions (very high confidence). Trends over Europe and North America are mostly weakly positive (LMM) or negative (TOST). For both approaches, the 2000–2021/22 trends decreased in magnitude compared to 1995–2021/22 for most regions; and for all time periods and regions, the pre-COVID trends are larger than the post-COVID trends. Our results enable the validation of global satellite TrOC trends and assessment of the performance of atmospheric chemistry models to represent the distribution and variation of TrOC
Architecture, Painting, and Everything in between: the Intermediality of Lancelot Blondeel
No full textDesigning for a large array of media during his career, the Bruges artist Lancelot Blondeel (1498-1561) is often regarded as a typical ‘product’ of the northern Renaissance. In this paper the gilded ornamental frameworks which so often dominate Blondeel’s paintings, will be taken as a starting point for an intermedial comparative analysis. While the few studies on Blondeel have mostly focussed on his role as painter, this paper aims to place his works in an immediate, dialectic relationship to contemporary metalwork, carved altarpieces and built architecture, set within a humanist social environment. The notion of architectural design and its connection to the liberal art geometry became instrumental in the growing artistic identity and changing status of the artist. As such, this paper seeks to understand how Blondeel’s training as a master mason informed his understanding of design as an intellectual concept by looking at the dynamics between painted architectural representations, early modern Netherlandish sculpture, architecture and metalwork as a synagonstic process
Enceladus Water Plume Modeling Using DSMC
Get PDFThis study investigates the water plumes of Saturn's moon, Enceladus, using Direct Simulation Monte Carlo (DSMC) modeling to analyze venting dynamics and plume structures. Building on prior research, we employ a parametrized DSMC approach to model water vapor and ice particle flows, leveraging Cassini spacecraft data from instruments such as the Ion and Neutral Mass Spectrometer and the Ultraviolet Imaging Spectrograph. The study explores whether vent conditions, such as mass flow rates, mixture temperatures, and particle sizes, can be inferred from observational data. We develop a computational framework to expand plume simulations beyond 10 km altitudes, incorporating gravitational and inertial forces in an Enceladus-fixed reference frame. A sensitivity analysis correlates vent parameters with observed data, identifying critical contributors such as vent orientation and location, mass flow rate, exit temperature, and ice grain characteristics. This approach reduces the dimensionality of fitting procedures, enabling robust parameter constraints and a more detailed understanding of plume dynamics. Key findings include constrained values for mass flow rates, ice grain radii assuming single-size particles, and exit temperatures (∼44–61 K), consistent with theoretical predictions. Additionally, variations in vent orientation and positional parameters were refined from the work of Porco et al. (2014, https://doi.org/10.1088/0004-6256/148/3/45). These results highlight the importance of collision dynamics in shaping plume structures. This work establishes a computationally efficient methodology for analyzing cryovolcanic plumes applicable to future missions exploring icy moons such as Enceladus or Europa. By prioritizing sensitive parameters, the study offers insights for optimizing observational strategies to maximize scientific yield
ENFORCE: Expertiserapport ref. exp_676 (390370582) & exp_677 (390369709), 14/05/2025
No full textDivergence of vessel diameter explains interspecific variation in hydraulic safety to salinity in the Sundarbans mangrove ecosystem
Get PDFVan Eyck Studies Colloquium
Get PDFSymposium XVIII for the Study of Underdrawing and Technology in Painting, Brussels, Royal Institute for Cultural Heritage and the Centre for the Study of the Flemish Primitives, 19-21 september 2012