cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Pulsational M_V versus [Fe/H] relation(s) for globular cluster RR Lyrae variables
Creators: name: Caputo, F.
name: Castellani, V.
name: Marconi, M.
name: Ripepi, V.
Publisher: name: arXiv
Year: 2000
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We use the results from recent computations of updated non-linear convective pulsating models to constrain the distance modulus of Galactic globular clusters through the observed periods of first overtone RRc pulsators. The resulting relation between the mean absolute magnitude of RR Lyrae stars and the heavy element content [Fe/H] appears well in the range of several previous empirical calibrations, but with a non linear dependence on [Fe/H] so that the slope of the relation increases when moving towards larger metallicities. On this ground, our results suggest that metal-poor ([Fe/H]-1.5) variables follow two different linear -[Fe/H] relations. Application to RR Lyrae stars in the metal-poor globular clusters of the Large Magellanic Cloud provides a LMC distance modulus of the order of 18.6 mag, thus supporting the "long" distance scale. The comparison with recent predictions based on updated stellar evolution theory is shortly presented and discussed.
description: 8 pages, 4 postscript figures, accepted for publication on MNRAS
Propulsori nucleari per mandare l’uomo su Marte
Creators: Valentina Guglielmo
Publisher: name: Media Inaf
Year: 2025

Per ridurre il tempo di viaggio in vista di un volo umano verso Marte, una possibilità sembra essere un nuovo tipo di radiatore modulare impiegato nella propulsione nucleare elettrica. Un sistema sicuramente potente in termini di performance, ma al contempo complicato e “ingombrante”. Per questo la Nasa ha coinvolto un team di esperti che per due anni lavorerà al progetto
Sognando di ricevere un messaggio da ET
Creators: Patrizia Caraveo
Publisher: name: Media Inaf
Year: 2025

Già lo scorso anno vi avevamo parlato su Media Inaf del libro di Graziano Chiaro “Sotto i cieli lontani”, un quadro aggiornato dello stato dell’arte della ricerca Seti. Ritorniamo oggi sull’argomento proponendovi con il consenso dell’autrice – l’astrofisica Patrizia Caraveo, che ne ha anche firmato la prefazione – questo articolo uscito la settimana scorsa sul Sole24Ore
Antifield BRST quantization of duality-symmetric Maxwell theory
Creators: name: Bekaert, Xavier
name: Cucu, Sorin
Publisher: name: arXiv
Year: 2000
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We perform the antifield BRST quantization of duality-symmetric Maxwell theory and show explicitly the quantum equivalence of the different formulations (covariant and non-covariant). The non-covariant gauge-fixed action is used in the computation of propagators for this model.
description: 19 pages, some clarifying sentences added, version published in JHEP 0101 (2001) 015
Advanced Computer Applications for The New Liberal Arts
Creators: name: Covey, Preston K.
Publisher: name: Carnegie Mellon University
Year: 1988
Subjects: subject: Philosophy
subject: FOS: Philosophy, ethics and religion

description: The ultimate goal of the grant from the Sloan Foundation to Carnegie Mellon University was to promote the quality and use of advanced computing in liberal arts education; an instrumental goal was to establish a resource center for doing so. The establishment of a research and development center was central to the project: to build a 'critical mass' of technical and academic expertise to provide a strategic vision for enhancing the 'new' liberal arts through advanced technology. In this context, the New Liberal Arts is meant simply to emphasize the full spectrum of modern arts and sciences: quantitative, technological and computer literacy as well as the qualitative, humanistic understandings traditionally associated with a liberal arts education. This broader understanding of the liberal arts has been emphasized at Carnegie Mellon from the beginning. The projects supported under the Sloan Foundation grant encompass the sciences, mathematics and the fine arts as well as the humanities and social sciences -- with a keen eye to the need for computer literacy and innovative computer applications in the more traditional liberal arts as well as the more technical and quantitative disciplines. Our projects address the needs of general science education as well as formal and quantitative work in traditional humanistic fields such as philosophy and history. We have also applied computer technology in striking and perhaps surprising ways to humanistic fields such as ethics and aesthetics -- where neither formal theory nor quantitative apparatus typically apply, but where rigorous methods of evidentiary analysis and hypothesis testing must prevail nonetheless.
Collective excitations in the Unitary Correlation Operator Method and relativistic QRPA studies of exotic nuclei
Creators: name: Paar, N.
name: Papakonstantinou, P.
name: Hergert, H.
name: Roth, R.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: The collective excitation phenomena in atomic nuclei are studied in two different formulations of the Random Phase Approximation (RPA): (i) RPA based on correlated realistic nucleon-nucleon interactions constructed within the Unitary Correlation Operator Method (UCOM), and (ii) relativistic RPA (RRPA) derived from effective Lagrangians with density-dependent meson-exchange interactions. The former includes the dominant interaction-induced short-range central and tensor correlations by means of an unitary transformation. It is shown that UCOM-RPA correlations induced by collective nuclear vibrations recover a part of the residual long-range correlations that are not explicitly included in the UCOM Hartree-Fock ground state. Both RPA models are employed in studies of the isoscalar monopole resonance (ISGMR) in closed-shell nuclei across the nuclide chart, with an emphasis on the sensitivity of its properties on the constraints for the range of the UCOM correlation functions. Within the Relativistic Quasiparticle RPA (RQRPA) based on Relativistic Hartree-Bogoliubov model, the occurrence of pronounced low-lying dipole excitations is predicted in nuclei towards the proton drip-line. From the analysis of the transition densities and the structure of the RQRPA amplitudes, it is shown that these states correspond to the proton pygmy dipole resonance.
description: 15 pages, 4 figures, submitted to Physics of Atomic Nuclei, conference proceedings, "Frontiers in the Physics of Nucleus", St. Petersburg, 28. June-1. July, 2005
Lanciato il razzo New Glenn di Blue Origin
Creators: Redazione Ansa
Publisher: name: Media Inaf
Year: 2025

L’azienda aerospaziale del fondatore di Amazon Jeff Bezos ha lanciato oggi in orbita da Cape Canaveral, alle 8:02 ora italiana, il suo primo razzo, New Glenn. L’obiettivo principale del test – il raggiungimento dell’orbita – ha avuto successo, ma non è stato possibile il recupero del booster, che non è riuscito ad atterrare sulla piattaforma Jacklyn, nell’oceano Atlantico
Quarantaquattro stelle sotto l’Arco del Drago
Creators: Federica Loiacono
Publisher: name: Media Inaf
Year: 2025

Utilizzando il telescopio Webb, un team di astronomi guidato dall'Università di Chiba ha rivelato ben quarantaquattro stelle nel Dragon Arc, una galassia a oltre sei miliardi di anni luce dalla Terra. I fenomeni di macro e microlensing gravitazionale hanno reso possibile la straordinaria osservazione. La scoperta su Nature Astronomy
Mind the gap! Gender differences in alcohol consumption among Swedish ninth graders 1989–2021
Creators: name: Raninen, Jonas
name: Ramstedt, M
name: Thor, S
name: Törrönen, J
Publisher: name: La Trobe
Year: 2024
Subjects: classificationCode: 321301
subject: Adolescent health
classificationCode: 52
subject: Psychology
subject: FOS: Psychology
classificationCode: 42
subject: Health sciences
subject: FOS: Health sciences
classificationCode: 44
subject: Human society
classificationCode: 520502
subject: Gender psychology

description: Introduction: To examine gender differences in drinking habits among Swedish ninth graders over the period 1989–2021. Methods: Annual school surveys with nationally representative samples of ninth-grade students in Sweden covering the period 1989–2021, total sample of 180,538 students. Drinking habits were measured with self-reports of frequency and quantity of use and frequency of heavy episodic drinking. Differences between genders were compared annually and differences were tested using logistic and ordinary least square regression models with cluster robust standard errors. Results: Small gender differences in the prevalence of alcohol use during the first part of the study period were followed by an increasing gap over the past decade with girls being more likely to drink alcohol than boys. Boys consumed larger amounts of alcohol than girls during the first three decades of the studied period but no gender differences were found in later years. Binge drinking was more prevalent among boys during 1989 to 2000 but no systematic gender difference was found during the past 15 years. Discussion and Conclusions: There used to be clear gender differences in drinking habits among ninth graders in Sweden with boys drinking more than girls. This gap has narrowed over the past three decades and among contemporary adolescents, no gender differences are found neither in binge drinking nor volume of drinking and the prevalence of drinking is even higher among girls.
Can a "pure vector" gravitational wave mimic a "pure tensor" one?
Creators: name: Allen, Bruce
Publisher: name: arXiv
Year: 2018
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences
subject: 83B05

description: In the general theory of relativity, gravitational waves have two possible polarizations, which are transverse and traceless with helicity $\pm 2$. Some alternatives theories contain additional helicity $0$ and helicity $\pm 1$ polarization modes. Here, we consider a hypothetical "pure vector" theory in which gravitational waves have only two possible polarizations, with helicity $\pm 1$. We show that if these polarizations are allowed to rotate as the wave propagates, then for certain source locations on the sky, the strain outputs of three ideal interferometric gravitational wave detectors can exactly reproduce the strain outputs predicted by general relativity.
description: 8 pages, including one figure. Updated to agree with version published in PRD. Typo corrected in Appendix
Adaptively rational learning
Creators: name: Wellen, Sarah
name: Danks, David
Publisher: name: Carnegie Mellon University
Year: 2015
Subjects: subject: Philosophy
subject: FOS: Philosophy, ethics and religion

description: Research on adaptive rationality has focused principally on inference, judgment, and decision-making that lead to behaviors and actions. These processes typically require cognitive representations as input, and these representations must presumably be acquired via learning. Nonetheless, there has been little work on the nature of, and justification for, adaptively rational learning processes. In this paper, we argue that there are strong reasons to believe that some learning is adaptively rational in the same way as judgment and decision-making. Indeed, overall adaptive rationality can only properly be assessed for pairs of learning and decision processes. We thus present a formal framework for modeling such pairs of cognitive processes, and thereby assessing their adaptive rationality relative to the environment and the agent’s goals. We then use this high-level formal framework on specific cases by (a) demonstrating how natural formal constraints on decision-making can lead to substantive predictions about adaptively rational learning and representation; and (b) characterizing adaptively rational learning for fast-and-frugal one-reason decision-making.
title: Operational Flexibility of a CFB Furnace during Fast Load Change—Experimental Measurements and Dynamic Model
Creators: name: Peters, Jens
name: Alobaid, Falah
name: Epple, Bernd
Publisher: name: UNSPECIFIED
Year: 2021

description: The share of power from fluctuating renewable energies such as wind and solar is increasing due to the ongoing climate change. It is therefore essential to use technologies that can compensate for these fluctuations. Experiments at 1 MWth scale were carried out to evaluate the operational flexibility of a circulating fluidized bed (CFB) combustor during transient operation from 60% to 100% load. A typical load following sequence for fluctuating electricity generation/demand was reproduced experimentally by performing 4 load changes. The hydrodynamic condition after a load change depends on if the load change was in positive or negative direction due to the heat stored in the refractory/bed material at high loads and released when the load decreases. A 1.5D-process simulation model was created in the software APROS (Advanced Process Simulation) with the target of showing the specific characteristics of a CFB furnace during load following operation. The model was tuned with experimental data of a steady-state test point and validated with the load cycling tests. The simulation results show the key characteristics of CFB combustion with reasonable accuracy. Detailed experimental data is presented and a core-annulus approach for the modeling of the CFB furnace is used.
Model Testing and Validation of EfficientVisionTransformer (EVT), a Deep Learning Model to Assure Quality and Accuracy
Creators: name: Emmanuel Chinyere Echeonwu, Moses Okechukwu Onyesolu, Bolou Dickson Bolou
Publisher: name: Zenodo
Year: 2024

description: This paper presents a rigorous testing and validation methodology for the EfficientVisionTransformer(EVT), a state-of-the-art deep learning model designed to predict vegetation indices from remotely sensed images in Southern Nigeria. Given the critical role of vegetation monitoring in ecological preservation and agricultural productivity, ensuring the accuracy and reliability of such models is paramount. The testing methodology uses a multi-pronged approach, including unit testing, integration testing, boundary value testing, and overall accuracy evaluation. Unit testing tested the correct operation of individual EVT components such as patch embedding, encoder, and decoder modules. Integration testing examined the flawless interoperability of various components, identifying any flaws in their interactions. Boundary value testing pushed the limits by evaluating the model's performance under extreme input situations, examining robustness and capacity to deal with edge cases. Importantly, accuracy testing using real-world data from Southern Nigeria demonstrated the EVT's prediction capabilities. The model has an amazing root mean square error of 0.04582. Furthermore, the normalized root mean square errors were 0.04582 when normalized to the 0-1 range and 0.00864 when normalized to the target variable's 1.8-7.1 range. These measurements show that the model is very accurate, with predictions departing from real vegetation index values by <1% of the whole data range on average. The extensive testing methodology established the EfficientVisionTransformeras a reliable and high-performing solution for predicting vegetation index in Southern Nigeria. The findings of this work provide major contributions to the advancement of remote sensing and deep learning research, as well as enabling more accurate vegetation monitoring, which is vital for ecological conservation, sustainable agriculture, and regional economic growth.
Anomaly cancellation in effective supergravity theories from the heterotic string: two simple examples
Creators: name: Gaillard, Mary K.
name: Leedom, Jacob
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We use Pauli-Villars regularization to evaluate the conformal and chiral anomalies in the effective field theories from Z3 and Z7 compactifications of the heterotic string without Wilson lines. We show that parameters for Pauli-Villars chiral multiplets can be chosen in such a way that the anomaly is universal in the sense that its coefficient depends only on a single holomorphic function of the three diagonal moduli. It is therefore possible to cancel the anomaly by a generalization of the four-dimensional Green-Schwarz mechanism. In particular we are able to reproduce the results of a string calculation of the four-dimensional chiral anomaly for these two models.
description: 26 pages
Computer simulations of interferometric imaging with the VLT interferometer and the AMBER instrument
Creators: name: Bloecker, T.
name: Hofmann, K. -H.
name: Przygodda, F.
name: Weigelt, G.
Publisher: name: arXiv
Year: 2000
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present computer simulations of interferometric imaging with the VLT interferometer and the AMBER instrument. These simulations include both the astrophysical modelling of a stellar object by radiative transfer calculations and the simulation of light propagation from the object to the detector (through atmosphere, telescopes, and the AMBER instrument), simulation of photon noise and detector read-out noise, and finally data processing of the interferograms. The results show the dependence of the visibility error bars on the following observational parameters: different seeing during the observation of object and reference star (Fried parameters r_0,object=2.4m, r_0,ref.=2.5m, different residual tip-tilt error (delta_tt,object=2% of the Airy disk diameter, delta_tt,ref.=0.1%), and object brightness (K_object=3.5 mag and 11 mag, K_ref.=3.5 mag). Exemplarily, we focus on stars in late stages of stellar evolution and study one of its key objects, the dusty supergiant IRC+10420 that is rapidly evolving on human timescales. We show computer simulations of VLTI interferometry of IRC+10420 with two ATs (wide-field mode, i.e. without fiber optics spatial filters) and discuss whether the visibility accuracy is sufficient to distinguish between different theoretical model predictions.
description: 10 pages including 6 PostScript figures, also available from http://www.mpifr-bonn.mpg.de/div/speckle/publications.html, SPIE Conf. Vol. 4006: Interferometry in Optical Astronomy, in press
Macchine del tempo: il podcast
Creators: Claudia Mignone
Publisher: name: Media Inaf
Year: 2025

Un tuffo spazio-temporale che parte dalla Terra e incrocia pianeti, stelle e galassie, fino a sfiorare l’origine del cosmo. Tutto questo è “Macchine del tempo”, il nuovo podcast ispirato alla grande mostra dell’Istituto nazionale di astrofisica, ideato e realizzato da Lucia Bucciarelli. Un episodio al mese, da gennaio a maggio, per esplorare le meraviglie dell’universo in un viaggio attraverso lo spazio, indietro del tempo
Greening (mehr Grün) und Browning (mehr Braun) - wie sind die Trends?
Creators: name: Breckle, Siegmar-W
name: Lozán, José L.
Publisher: name: Universität Hamburg
Year: 2021
Subjects: Greening (more green), browning (more brown), Changes in vegetation, extended vegetation period, nitrogen input, CO2 fertilization, water stress, Mediterranean region.

description: Seit einigen Jahrzehnten werden Veränderungen der Vegetation auf der Erdoberfläche beobachtet. Es gibt Berichte darüber, dass einige Regionen grüner werden. Als Gründe dafür werden die verlängerte Vegeta­tionszeit, Stickstoffeintrag und CO2-Düngung u.a. genannt. In anderen Regionen wird die Vegetation dagegen braun möglicherweise als Folge von Wasserstress. In diesem Beitrag wird diese Entwicklung anhand von Beobachtungen aus dem Mediterrangebiet näher eingegangen und mit globalen Ergebnissen anderer Untersuchungen verglichen und bewertet. Greening (more green) and browning (more brown), what are the trends? Changes in vegetation on the earth‘s surface have been observed for the last decades. There are reports that some regions are becoming greener. The reasons given for this are the extended vegetation period, nitrogen input and CO2 fertilization, among others. In other regions, however, the vegetation may turn brown maybe as a result of water stress. In this article, this development is examined in more detail using case studies from the Mediterranean region and compared and evaluated with global results from several others investigations. Enverdeciendo (greening) y Marroneando (Browning), cuales son las tendencias? Durante las últimas décadas se ha venido observando cambios en la vegetación de la superficie terrestre. Hay informes de que algunas regiones se están volviendo más verdes. Las razones que se dan como explicación a ésto son el período vegetativo de las plantas más extendido, el aporte de nitrógeno y la fertilización del CO2, entre otros. En otras regiones, sin embargo, la vegetación esta volviendose más marrón posiblemente como resultado del estrés hídrico. En este artículo, se examina este desarrollo con más detalle basandose en observaciones de la región mediterránea comparándolas y evaluándolas con resultados globales de muchos otros estudios.
Muon Reconstruction in the Daya Bay Water Pools
Creators: name: Hackenburg, R. W.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: Muon reconstruction in the Daya Bay water pools would serve to verify the simulated muon fluxes and offer the possibility of studying cosmic muons in general. This reconstruction is, however, complicated by many optical obstacles and the small coverage of photomultiplier tubes (PMTs) as compared to other large water Cherenkov detectors. The PMTs' timing information is useful only in the case of direct, unreflected Cherenkov light. This requires PMTs to be added and removed as an hypothesized muon trajectory is iteratively improved, to account for the changing effects of obstacles and direction of light. Therefore, muon reconstruction in the Daya Bay water pools does not lend itself to a general fitting procedure employing smoothly varying functions with continuous derivatives. Here, an algorithm is described which overcomes these complications. It employs the method of Least Mean Squares to determine an hypothesized trajectory from the PMTs' charge-weighted positions. This initially hypothesized trajectory is then iteratively refined using the PMTs' timing information. Reconstructions with simulated data reproduce the simulated trajectory to within about 5 degrees in direction and about 45 cm in position at the pool surface, with a bias that tends to pull tracks away from the vertical by about 3 degrees.
description: Supplementary materials available in the journal-published version
Academic Superstars: Competent or Lucky?
Creators: name: Heesen, Remco
Publisher: name: Carnegie Mellon University
Year: 2016
Subjects: subject: Philosophy
subject: FOS: Philosophy, ethics and religion

description: I show that the social stratification of academic science can arise as a result of academics' preference for reading work of high epistemic value. This is consistent with a view on which academic superstars are highly competent academics, but also with a view on which superstars arise primarily due to luck. I argue that stratification is beneficial if most superstars are competent, but not if most superstars are lucky. I also argue that it is impossible to tell whether most superstars are in fact competent or lucky, or which group a given superstar belongs to, and hence whether stratification is overall beneficial.
title: Accounting for Local Geological Variability in Sequential Simulations—Concept and Application
Creators: name: Linsel, Adrian
name: Wiesler, Sebastian
name: Haas, Joshua
name: Bär, Kristian
name: Hinderer, Matthias
Publisher: name: MDPI
Year: 2021

description: Heterogeneity-preserving property models of subsurface regions are commonly constructed by means of sequential simulations. Sequential Gaussian simulation (SGS) and direct sequential simulation (DSS) draw values from a local probability density function that is described by the simple kriging estimate and the local simple kriging variance at unsampled locations. The local simple kriging variance, however, does not necessarily reflect the geological variability being present at subsets of the target domain. In order to address that issue, we propose a new workflow that implements two modified versions of the popular SGS and DSS algorithms. Both modifications, namely, LVM-DSS and LVM-SGS, aim at simulating values by means of introducing a local variance model (LVM). The LVM is a measurement-constrained and geology-driven global representation of the locally observable variance of a property. The proposed modified algorithms construct the local probability density function with the LVM instead of using the simple kriging variance, while still using the simple kriging estimate as the best linear unbiased estimator. In an outcrop analog study, we can demonstrate that the local simple kriging variance in sequential simulations tends to underestimate the locally observed geological variability in the target domain and certainly does not account for the spatial distribution of the geological heterogeneity. The proposed simulation algorithms reproduce the global histogram, the global heterogeneity, and the considered variogram model in the range of ergodic fluctuations. LVM-SGS outperforms the other algorithms regarding the reproduction of the variogram model. While DSS and SGS generate a randomly distributed heterogeneity, the modified algorithms reproduce a geologically reasonable spatial distribution of heterogeneity instead. The new workflow allows for the integration of continuous geological trends into sequential simulations rather than using class-based approaches such as the indicator simulation technique.
Biogeochemische und biogeophysikalische Effekte von Landnutzungsänderungen
Creators: name: Kasang, Dieter
name: Bathiany, Sebastian
Publisher: name: Universität Hamburg
Year: 2021
Subjects: Biogeochemical effects, biogeophysical effects, land use changes, land surfacechanges, forests, cropland, pasture,

description: Seit Jahrtausenden verändert der Mensch nicht nur seine unmittelbare Umwelt, sondern beeinflusst vor allem durch die Umwandlung von Wald in Acker- und Weideland auch das Klima. Dabei sind zwei grundsätzlich verschiedene Prozesse zu unterscheiden: die biogeochemischen Folgen durch die Emission von Treibhausgasen und die biogeophysikalischen Folgen durch die Veränderung der Landoberfläche. Dieser Artikel erläutert deren klimatische Konsequenzen und versucht eine quantitative Abschätzung der durch die anthropogene Landnutzung verursachten Änderungen der globalen sowie der regionalen Temperatur. Zum Schluss wird die Frage gestellt, ob durch Landnutzungsänderungen eine Begrenzung des anthropogenen Klimawandels möglich ist. Biogeochemical and biogeophysical effects of land use changes: For thousands of years, humans have not only been changing their immediate environment, but also influencing the climate, especially through the conversion of forests into cropland and pasture. Two fundamentally different processes must be distinguished: a) the biogeochemical impacts due to the emission of greenhouse gases and b) the biogeophysical impacts due to changes in the land surface. This article explains their climatic consequences and attempts a quantitative estimate of the changes in global as well as regional temperature caused by anthropogenic land use. It concludes by asking whether land-use changes can limit anthropogenic climate change. Efectos biogeoquímicos y biogeofísicos por los cambios en el uso de la tierra: Desde hace miles de años, el ser humano no sólo ha modificado su entorno inmediato, sino que también ha influienciado el clima, especialmente mediante la conversión de bosques en tierras de cultivo y pastos. Hay que distinguir dos procesos fundamentalmente diferentes: a) las consecuencias biogeoquímicas debidas a la emisión de gases de efecto invernadero y b) las consecuencias biogeofísicas debidas a los cambios en la superficie terrestre. Este artículo explica sus consecuencias climáticas e intenta hacer una estimación cuantitativa de los cambios en la temperatura global y regional causados por el uso antropogénico de la tierra. Por último, se plantea la cuestión de si es posible limitar el cambio climático antropogénico mediante cambios en el uso del suelo.
Mode identification of Pulsating White Dwarfs using the HST
Creators: name: Kepler, S. O.
name: Robinson, E. L.
name: Koester, D.
name: Clemens, J. C.
name: Nather, R. E.
name: Jiang, X. J.
Publisher: name: arXiv
Year: 2000
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We have obtained time-resolved ultraviolet spectroscopy for the pulsating DAV stars G226-29 and G185-32, and for the pulsating DBV star PG1351+489 with the Hubble Space Telescope Faint Object Spectrograph, to compare the ultraviolet to the optical pulsation amplitude and determine the pulsation indices. We find that for essentially all observed pulsation modes, the amplitude rises to the ultraviolet as the theoretical models predict for l=1 non-radial g-modes. We do not find any pulsation mode visible only in the ultraviolet, nor any modes whose phase flips by 180 degrees; in the ultraviolet, as would be expected if high l pulsations were excited. We find one periodicity in the light curve of G185-32, at 141 s, which does not fit theoretical models for the change of amplitude with wavelength of g-mode pulsations.
description: Accepted for publication in the Astrophysical Journal, Aug 2000
title: A New Design of an Integrated Solar Absorption Cooling System Driven by an Evacuated Tube Collector: A Case Study for Baghdad, Iraq
Creators: name: Al-Falahi, Adil
name: Alobaid, Falah
name: Epple, Bernd
Publisher: name: MDPI
Year: 2021

description: The electrical power consumption of refrigeration equipment leads to a significant influence on the supply network, especially on the hottest days during the cooling season (and this is besides the conventional electricity problem in Iraq). The aim of this work is to investigate the energy performance of a solar-driven air-conditioning system utilizing absorption technology under climate in Baghdad, Iraq. The solar fraction and the thermal performance of the solar air-conditioning system were analyzed for various months in the cooling season. It was found that the system operating in August shows the best monthly average solar fraction (of 59.4%) and coefficient of performance (COP) (of 0.52) due to the high solar potential in this month. Moreover, the seasonal integrated collector efficiency was 54%, providing a seasonal solar fraction of 58%, and the COP of the absorption chiller was 0.44, which was in limit, as reported in the literature for similar systems. A detailed parametric analysis was carried out to evaluate the thermal performance of the system and analyses, and the effect of design variables on the solar fraction of the system during the cooling season.
A Variant of the Double-Negation Translation
Creators: name: Avigad, Jeremy
Publisher: name: Carnegie Mellon University
Year: 2006
Subjects: subject: Philosophy
subject: FOS: Philosophy, ethics and religion

description: An efficient variant of the double-negation translation explains the relationship between Shoenfield’s and Gödel’s versions of the Dialectica interpretation.
Il satellite Gaia va in pensione
Creators: Claudia Mignone
Publisher: name: Media Inaf
Year: 2025

Oggi, 15 gennaio 2025, il satellite Gaia dell'Agenzia spaziale europea ha terminato la sua fase osservativa e, dopo una serie di test tecnologici previsti nelle prossime settimane, sarà spento definitivamente il 27 marzo. La fase scientifica della missione, che ha mappato con precisione inaudita quasi due miliardi di stelle della Via Lattea, andrà avanti ancora per molti anni, con la quarta data release prevista per il 2026
Valeria Zanini alla guida della Sisfa
Creators: Valentina Guglielmo
Publisher: name: Media Inaf
Year: 2025

Intervista a Valeria Zanini, astronoma all’Inaf di Padova ora eletta presidente della Società italiana degli storici della fisica e dell'astronomia. Come prima astronoma e prima donna in questo incarico, Zanini si propone di aumentare il dialogo all’interno della società e di trovare opportunità per i giovani nello studio della storia dell’astronomia
Thermodynamics and small quantum systems
Creators: name: Nieuwenhuizen, Th. M.
Publisher: name: arXiv
Year: 2003
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Small quantum systems non-weakly coupled to a bath become in the quantum regime surrounded by a cloud of photons or phonons, which modifies their thermodynamic behavior. Exactly solvable examples are the Brownian motion of a quantum particle in a harmonic confining potential and coupled to a harmonic quantum thermal bath, e.g. an ion in a Penning trap, and a spin immersed in a bosonic bath, as occurs in NMR physics. It appears that the Clausius inequality $\dbarrm Q\le T\d S$ can be violated. For non-adiabatic changes of system parameters the rate of energy dissipation can be negative, and, out of equilibrium, cyclic processes are possible which extract work from the bath. Experimental setups for testing some of the effects are discussed.
description: Invited talk at `Physics of Quantum Electronics 33', Snowbird, January 2003. 13 pages, 2 figures
title: Influence of Al2O3 Addition on Structure and Mechanical Properties of Borosilicate Glasses
Creators: name: Bruns, Sebastian
name: Uesbeck, Tobias
name: Weil, Dominik
name: Möncke, Doris
name: van Wüllen, Leo
name: Durst, Karsten
name: de Ligny, Dominique
Publisher: name: Frontiers
Year: 2021

description: Alkali-borosilicate glasses are one of the most used types of glasses with a high technological importance. In order to optimize glasses for diverse applications, an understanding of the correlation between microscopic structure and macroscopic properties is of central interest in materials science. It has been found that the crack initiation in borosilicate glasses can be influenced by changes in network interconnectivity. In the NBS2 borosilicate glass system (74.0SiO2-20.7B2O3-4.3Na2O-1.0Al2O3 in mol%) two subnetworks are present, i.e., a silicate and a borate network. Increasing cooling rates during processing were found to improve glasses crack resistance. Simultaneously, an increase in the network interconnectivity accompanied by an increasing capacity for densification were noticed. Their individual contribution to the mechanic response, however, remained unclear. In the present study the borosilicate glasses were systematically modified by addition of up to 4.0 mol% Al2O3. Changes in the network connectivity as well as the short- and medium-range order were characterized using Raman and NMR spectroscopy. Both the Raman and the 11B NMR results show that four-fold-coordinated boron is converted into three-fold-coordination as the Al2O3 content increases. Additionally, 27Al NMR experiments show that aluminum is dominantly present in four-fold coordination. Aluminum-tetrahedra are thus charge balanced by sodium ions and incorporated into the silicate network. Finally, nanoindentation testing was employed to link the inherent glass structure and its network configuration to the mechanical glass response. It was found that the glass softens with increasing Al2O3 content, which enhances the crack resistance of the borosilicate glass.
Feuer und Bodenbedeckung
Creators: name: Kasang, Dieter
Publisher: name: Universität Hamburg
Year: 2021
Subjects: Fire, land cover, terrestrial ecosystems, distribution of vegetation zones, change of ecosystems

description: Feuer ist ein grundlegendes Element der terrestrischen Ökosysteme und steht mit der Vegetation, dem Klima und den menschlichen Aktivitäten in komplexen Wechselbeziehungen. Es beeinflusst die geographische Verteilung von Vegetationszonen und ist an der gegenwärtigen dynamischen Änderung der Ökosysteme durch direkte anthropogene Eingriffe und den Klimawandel aktiv beteiligt. Andererseits verändern Ökosysteme und ihre Veränderungen durch den Menschen und das Klima die Art, die Ausbreitung und die Häufigkeit von Bränden. Fire and land cover: Fire is a fundamental element of terrestrial ecosystems and interacts in a complex manner with vegetation, climate, and human activities. It influences the geographic distribution of vegetation zones and is actively involved in the current dynamic change of ecosystems due to direct anthropogenic interventions and climate change. On the other hand, ecosystems and their changes due to humans and climate alter the nature, spread, and frequency of fires. Fuego y coverura vegetal terrestre: El fuego es un elemento fundamental de los ecosistemas terrestres y tiene complejas interrelaciones con la vegetación, el clima y las actividades humanas. Influye en la distribución geográfica de las zonas de vegetación y participa activamente en el cambio dinámico actual de los ecosistemas a través de intervenciones antropogénicas directas y el cambio climático. Por otro lado, los ecosistemas y sus cambios provocados por los seres humanos y el clima cambian el tipo, la propagación y la frecuencia de los incendios.
A Uniformly Consistent Estimator of Causal Effects under the kk-Triangle-Faithfulness Assumption
Creators: name: Spirtes, Peter
name: Jiji  Zhang
Publisher: name: Carnegie Mellon University
Year: 2014
Subjects: subject: Philosophy
subject: FOS: Philosophy, ethics and religion

description: Spirtes, Glymour and Scheines [Causation, Prediction, and Search (1993) Springer] described a pointwise consistent estimator of the Markov equivalence class of any causal structure that can be represented by a directed acyclic graph for any parametric family with a uniformly consistent test of conditional independence, under the Causal Markov and Causal Faithfulness assumptions. Robins et al. [Biometrika 90 (2003) 491–515], however, proved that there are no uniformly consistent estimators of Markov equivalence classes of causal structures under those assumptions. Subsequently, Kalisch and Bühlmann [J. Mach. Learn. Res. 8 (2007) 613–636] described a uniformly consistent estimator of the Markov equivalence class of a linear Gaussian causal structure under the Causal Markov and Strong Causal Faithfulness assumptions. However, the Strong Faithfulness assumption may be false with high probability in many domains. We describe a uniformly consistent estimator of both the Markov equivalence class of a linear Gaussian causal structure and the identifiable structural coefficients in the Markov equivalence class under the Causal Markov assumption and the considerably weaker k-Triangle-Faithfulness assumption.
Die Vernichtung der tropischen Regenwälder
Creators: name: Homeier, Jürgen
Publisher: name: Universität Hamburg
Year: 2021
Subjects: tropical rainforests, rainforest destruction, degradation, habitat.

description: Dieser Beitrag gibt einen Überblick über den gegenwärtigen Stand der Zerstörung der tropischen Regenwälder, beschreibt das Zusammenwirken der wichtigsten Faktoren und wie mögliche Folgen des Verlustes und der Degradierung dieses einzigartigen Lebensraumes aussehen werden. The destruction of the tropical rainforests: This article gives an overview of the current status of tropical rainforest destruction, describes the interaction of the main factors and what the possible consequences of the loss and degradation of this unique habitat will be. La destrucción de las selvas tropicales: Este artículo ofrece una descripción general del estado actual de la destrucción de las selvas tropicales, describe la interacción de los factores más importantes y cómo serán las posibles consecuencias de la pérdida y degradación de este hábitat único.
Complex Gravity and Noncommutative Geometry
Creators: name: Chamseddine, Ali H.
Publisher: name: arXiv
Year: 2000
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The presence of a constant background antisymmetric tensor for open strings or D-branes forces the space-time coordinates to be noncommutative. An immediate consequence of this is that all fields get complexified. By applying this idea to gravity one discovers that the metric becomes complex. Complex gravity is constructed by gauging the symmetry $U(1,D-1)$. The resulting action gives one specific form of nonsymmetric gravity. In contrast to other theories of nonsymmetric gravity the action is both unique and gauge invariant. It is argued that for this theory to be consistent one must prove the existence of generalized diffeomorphism invariance. The results are easily generalized to noncommutative spaces.
description: 10 pages. Talk given at the Strings 2000 meeting, July 10-15 2000, University of Michigan, Ann Arbor
BALIQCHILIK XO'JALIKLARIDA BALIQLAR LERNEOZINI KELIB CHIQISH SABABLARI VA ULARNI BARTARAF ETISH TADBIRLARI
Creators: name: N.A.Sulaymanova tayanch doktorant, S.I.Mavlonov v.f.d, professor, Veterinariya ilmiy-tadqiqot instituti
Publisher: name: Zenodo
Year: 2024

description: Maqolada sun’iy suv havzalarida boqilayotgan baliqlar lerneozining kelibchiqish sabablari haqidagi ilmiy manbalar tahlili va qisman amaliy ishlar xulosasi bayon etilgan
Come diventare milionari ripulendo la Luna
Creators: Chiara Badia
Publisher: name: Media Inaf
Year: 2025

Si chiama LunaRecycle Challenge,  mette in palio 3 milioni di dollari ed è l’ultima competizione lanciata dalla Nasa per le migliori innovazioni e soluzioni tecnologiche nel riciclo dei rifiuti durante le missioni spaziali di lunga durata. L’iniziativa è stata ideata dall’agenzia americana insieme all'Università dell’Alabama e all’azienda AI SpaceFactory. A vincere potrete essere proprio voi e la vostra squadra di “spazzini lunari”
Isospin Transport at Fermi Energies
Creators: name: Baran, V.
name: Colonna, M.
name: Di Toro, M.
name: Zielinska-Pfabe, M.
name: Wolter, H. H.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: In this paper we investigate isospin transport mechanisms in semi-peripheral collisions at Fermi energies. The effects of the formation of a low density region (neck) between the two reaction partners and of pre-equilibrium emission on the dynamics of isospin equilibration are carefully analyzed. We clearly identify two main contributions to the isospin transport: isospin diffusion due to the $N/Z$ ratio and isospin drift due to the density gradients. Both effects are sensitive to the symmetry part of the nuclear Equation of State (EOS), in particular to the value and slope around saturation density.
description: 6 pages, 6 figures, revtex4-twocolumns
title: Simulation Study of the Formation of Corrosive Gases in Coal Combustion in an Entrained Flow Reactor
Creators: name: von Bohnstein, Maximilian
name: Yildiz, Coskun
name: Frigge, Lorenz
name: Ströhle, Jochen
name: Epple, Bernd
Publisher: name: MDPI
Year: 2021

description: Gaseous sulfur species play a major role in high temperature corrosion of pulverized coal fired furnaces. The prediction of sulfur species concentrations by 3D-Computational Fluid Dynamics (CFD) simulation allows the identification of furnace wall regions that are exposed to corrosive gases, so that countermeasures against corrosion can be applied. In the present work, a model for the release of sulfur and chlorine species during coal combustion is presented. The model is based on the mineral matter transformation of sulfur and chlorine bearing minerals under coal combustion conditions. The model is appended to a detailed reaction mechanism for gaseous sulfur and chlorine species and hydrocarbon related reactions, as well as a global three-step mechanism for coal devolatilization, char combustion, and char gasification. Experiments in an entrained flow were carried out to validate the developed model. Three-dimensional numerical simulations of an entrained flow reactor were performed by CFD using the developed model. Calculated concentrations of SO2, H2S, COS, and HCl showed good agreement with the measurements. Hence, the developed model can be regarded as a reliable method for the prediction of corrosive sulfur and chlorine species in coal fired furnaces. Further improvement is needed in the prediction of some minor trace species.
Cicrumnuclear Supernova Remnants and HII Regions in NGC 253
Creators: name: Ulvestad, James S.
Publisher: name: arXiv
Year: 2000
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Archival VLA data has been used to produce arcsecond-resolution 6- and 20-cm images of the region surrounding the nuclear 200-pc (~15") starburst in NGC 253. Twenty-two discrete sources stronger than 0.4 mJy have been detected within ~2 kpc (~3') of the galaxy nucleus; almost all these sources must be associated with the galaxy. None of the radio sources coincides with a detected X-ray binary, so they appear to be due to supernova remnants and H II regions. The region outside the central starburst has a derived radio supernova rate of
description: 17 pages, 3 postscript figures, AASTeX format, in press for Astronomical Journal, July 2000
Dagli abissi al cielo, una Terra di rifiuti
Creators: Valentina Guglielmo
Publisher: name: Media Inaf
Year: 2025

Pubblicata su One Earth una proposta per le Nazioni Unite di creare un nuovo Obiettivo di sviluppo sostenibile, il diciottesimo, per la tutela dell’orbita terrestre dai detriti spaziali. Un problema che si sta aggravando, come sottolinea l’ultimo report annuale sull’ambiente spaziale dell’Esa, ma per il quale non sono ancora state prese contromisure efficaci