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Featured
How a robot in deep water can bring enlightenment
Engineering (Civil engineering)
Date of upload:
04.07.2018
Co-author:
Caption:
Made by euronews: the most watched news channel in Europe
The QuEST for Sunspots
Natural Sciences (Astrophysics and Astrononmy)
Date of upload:
17.07.2019
Co-author:
Caption:
Observing sunspots, Galileo discovered the rotation of the Sun… George Ellery Hale discovered that they have intense magnetic fields…But there are still many open questions about these enigmatic structures. EST will help answer them.
Episode II: The QuEST for Spicules
Natural Sciences (Astrophysics and Astrononmy)
Date of upload:
14.04.2020
Co-author:
Caption:
The surface of the Sun is covered in features that look like needles or hairs, called "spicules". They were discovered in the 19th century by Angelo Secchi. But we still do not know their origin, their magnetic fields or their possible contribution to the heating of the solar atmosphere... Walk with Father Secchi to "The QuEST for Spicules", the second episode of our cartoons video series "The QuEST"! (See more at http://www.est-east.eu/est/index.php/outreach?id=745)
Basic Concepts of Financial Literacy
Economics (Finance)
Date of upload:
06.05.2020
Co-author:
Caption:
Video demonstrating basic concepts of financial literacy with calculations.
Quasi-periodic pulsations in stellar flares
Natural Sciences (Astrophysics and Astrononmy)
Date of upload:
10.09.2015
Co-author:
Chloe Pugh, Valery Nakariakov
Abstract:
Quasi-periodic pulsations (QPPs) are a common feature of solar flares that are observed in many different wavelengths. Although QPPs appear not to be as abundant in white light Kepler flare light curves as they are in solar flares, albeit in different wavelengths the structure of the pulsations are strikingly similar, hinting that the same underlying processes govern both solar and stellar flares. Here we consider a special case, observed on KIC9655129, which shows evidence of multiple periodicities. We speculate that the presence of multiple periodicities is a good indication that the QPPs were caused by magnetohydrodynamic oscillations, further strengthening the case that the physical processes in operation during stellar flares are at least analogous to those in solar flares.
Observations of Red Giants with SONG
Natural Sciences (Astrophysics and Astrononmy)
Date of upload:
03.08.2016
Co-author:
Abstract:
One of the outstanding and unforeseen results from the Kepler mission is our new insight and understanding of red giant stars. These highly evolved stars, which are in the last stages of their life, provide extremely useful information when trying to develop stellar evolutionary models. Furthermore, they show stochastically excited oscillations thus allowing to use asteroseismic techniques to derive conditions of the most internal layers. Bright giants stars are well suited to be studied with the 1m telescopes in the Stellar Observations Network Group project (SONG) using a high resolution echelle spectrograph performing high precision measurements of their the radial velocity. The prototype node- the Hertzsprung SONG telescope- was inaugurated in October 2014 and is located at the Teide Observatory on Tenerife and providing continuous and high quality observations since then, When selecting the best targets for SONG, a precision of 1-2 m/s per point is reachable using the iodine method and a number of red giants have been observed with the SONG telescope since scientific operation started. In this talk we present the first results of these specific campaigns for a few red giants in which eigenmodes have been identified and their global seismic parameters derived.
Comparison of damping mechanisms for transverse waves in coronal loops.
Natural Sciences (Astrophysics and Astrononmy)
Date of upload:
22.01.2017
Co-author:
I. Arregui
Abstract:
Damping of transverse waves in different solar coronal structures is a commonly observed property and a source of information about coronal conditions. Although resonant damping seems to be the most accepted mechanism for damping of transverse waves, there are other possible mechanisms. We have carried out a Bayesian analysis comparing three different models which could explain the damping in coronal loops. Our results indicate that resonant absorption is the most probable mechanism for low ratios between damping time and wave period, while the wave leakage mechanism is the best candidate for high ratios. Nonetheless, the evidence for one model against another shows a strong dependence on the data errors.
Reconnection between emerging and pre-existing magnetic fields observed with IRIS: a case study for EST observations
Natural Sciences (Astrophysics and Astrononmy)
Date of upload:
19.06.2018
Co-author:
F. Zuccarello, P.R. Young, P. Romano, M. Murabito
Abstract:
We report multi-wavelength ultraviolet observations taken with the IRIS satellite, concerning the emergence phase in the upper chromosphere and transition region of an emerging flux region (EFR) embedded in the unipolar plage of active region NOAA 12529. These data are complemented by full-disk, simultaneous observations of the Solar Dynamics Observatory satellite, relevant to the photosphere and the corona. The photospheric configuration of the EFR is also analyzed by measurements taken with the spectropolarimeter aboard the Hinode satellite, when the EFR was fully developed. Recurrent intense brightenings that resemble UV bursts, with counterparts in all coronal passbands, are identified at the edges of the EFR and in the region of the arch filament system (AFS) cospatial to the EFR. Jet activity is also found at chromospheric and coronal levels, near the AFS and the observed brightness enhancement sites. The analysis of the IRIS line profiles reveals the heating of dense plasma in the low solar atmosphere and the driving of bi-directional high-velocity flows with speeds up to 100 km/s at the same locations. Comparing these signatures with previous observations and numerical models, we suggest evidence of several long-lasting, small-scale magnetic reconnection episodes occurring between the emerging bipole and the ambient field. This process leads to the cancellation of a pre-existing photospheric flux concentration of the plage with the opposite polarity flux patch of the EFR. Moreover, the reconnection appears to take place higher in the atmosphere than usually found in UV bursts, explaining the observed coronal counterparts. These observations provide a case study for the EST science requirements, as higher spatial and temporal resolution are necessary to better understand and characterize the onset and development of such small-scale reconnection events.
Gas towards the Gamma­-ray-­Emitting Supernova Remnant W28 (and others)
Natural Sciences (Astrophysics and Astrononmy)
Date of upload:
21.12.2015
Co-author:
Gavin Rowell, Matthieu Renaud, Phoebe de Wilt, Fabien Voisin, Yasuo Fukui, Michael Burton, Andrew Walsh, Akiko Kawamura, Andrew Walsh, Akiko Kawamura, Felix Aharonian
Abstract:
We present the results of molecular spectral line observations towards Supernova Remnants such as W28, RX J1713.7-3946 and HESS J1731-347. These remnants exhibit TeV gamma-ray emission, beacons for the presence of enhanced populations of high energy particles. It follows that these objects may accelerate Galactic cosmic-ray protons via the diffusive shock mechanism, but knowledge of the environment local to such remnants is required to constrain such scenarios. The Mopra radio telescope is ideal for probing the interstellar environments of HESS gamma-ray sources through large-scale molecular line surveys. Mopra can be employed to hunt for dense gas-tracing CS and NH3 transitions to identify potential cosmic-ray target material, while simultaneously searching for shock-tracing SiO emission lines which can directly highlight shock-disrupted gas. Furthermore, spectral line width gives an insight into gas dynamics and Mopra is capable of measuring this at a ~1' resolution over degree-scale regions. We present results from recent 7 and 12mm surveys towards the above-mentioned TeV-emitting Supernova Remnants and discuss the implications for distance, the diffusion of cosmic-rays and the high energy gamma-ray spectrum.
Survival and activity of bacteria in air: Why do we care?
Natural Sciences (Biology)
Date of upload:
25.04.2016
Co-author:
Kai Finster, Meilee Ling, Maher Sahyoun, Morten Dreyer, Stine Holm, Martin Rasmussen, Stephanie Pilgaard
Abstract:
The presentation deals with activity of airborne microbial cells and how this is important for expanding our understanding of habitability and biosignatures.
Field line helicity as a tool for coronal physics
Natural Sciences (Physics)
Date of upload:
22.11.2017
Co-author:
G. Hornig, M.H. Page
Abstract:
What if there were a way to identify **where** the magnetic helicity is concentrated within a three- dimensional magnetic field? At first sight this question appears meaningless, since magnetic helicity is an integral over the whole volume of the magnetic field. But, in fact, it is possible to decompose this total helicity as an integral over individual "field line helicities" for each magnetic field line in the domain. All of these are ideal-invariant, topological quantities, and they allow us to quantify in a meaningful way how magnetic helicity is distributed within the domain. In this talk, I will show how this idea can be practically applied to typical extrapolations of the Sun's coronal magnetic field that are used in solar physics.
Development of instrumentation for solar observations at the Brazilian National Institute for Space
Natural Sciences (Physics)
Date of upload:
15.11.2018
Co-author:
Abstract:
The solar electromagnetic and corpuscular emissions are strongly modulated by the evolution of the magnetic structure of the solar atmosphere, which is imprinted in the solar surface. The evolution of the magnetic structure leads to gradual changes in the solar activity (space climate) as well as violent events (space weather) that affect the whole Heliosphere. In particular, the solar output affects the ionized and neutral components of the Earth’s atmosphere that have a direct impact on human activities from agriculture to high-technological systems. The solar magnetism is driven by the energy transport from the inner layers to the solar atmosphere. Although systematic observations have revealed several features related to the evolution of solar activity, there is not a complete explanation of the physical processes that lead to solar activity cyclic variability and its long-term changes. Here we present a brief description of the development of a magnetograph and visible-light imager instrument to study the solar dynamo processes through observations of the solar surface magnetic field distribution. The instrument will provide measurements of the vector magnetic field and the line-of-sight velocity in the solar photosphere. As the magnetic field anchored at the solar surface produces most of the structures and energetic events in the upper solar atmosphere and significantly influences the Heliosphere, the development of this instrument plays an essential role in reaching the scientific goals of The Atmospheric and Space Science Coordination (CEA) at the Brazilian National Institute for Space Research (INPE). In particular, the INPE’s Space Weather program will benefit most from the development of this technology. Additionally, we expect that this project will be the starting point to establish a robust research program on Solar System Research at INPE. The proposed instrument has been designed to operate on the ground, but with a conceptual design flexible enough to be adapted to work on a balloon and space-based platforms. In this way, our main aim is acquiring know-how progressively to build state-of-art solar vector magnetograph and visible-light imagers for space-based platforms to contribute to the efforts of the solar-terrestrial physics community to address the main unanswered questions on how our nearby Star works.
SPH Simulations of Abrasive Processes at a Microscopic Scale
Engineering (Mechanical engineering)
Date of upload:
30.06.2015
Co-author:
Claas Bierwisch, Hanna Lagger, Michael Moseler
Abstract:
We present the development of smoothed particle hydrodynamics (SPH) simulations for the investigation of the industrial application of abrasive flow machining (AFM). This process cannot be observed in-situ in experiments and therefore demands for numerical simulations at a grain-size process scale. There are only a few numerical models available for the AFM process, which are strongly simplified. In order to optimize the machining, an explicit approach of including individual grains in the abrasive suspension is essential. These grains are simulated by individual clusters of SPH particles, which are integrated in time by a rigid body solver. For the correct force transmission between the suspended abrasive particle and the workpiece, a realistic representation of the stress in the fluid model of the suspension is necessary. Therefore, the rheology of the fluids, containing the abrasive grains, has been experimentally characterized. Since the tested suspensions show a viscoelastic behavior, we have employed a viscoelastic fluid model and have used experimentally gathered data for the calibration of the applied numerical model. The abrasive process on a workpiece and the removal of material from its surface is modeled by the Johnson-Cook ductile flow stress model in combination with a strain-based failure criterion. We show that the particle method can reproduce key aspects for the simulation of the process of abrasive flow machining. By the application of the Johnson-Cook model, we are able to determine wear contacts between solid materials on a microscopic scale.
Disease modelling, biomarkers and virtual physiology - the role of jcpex! and U-CEP
Computer Sciences (Artificial intelligence)
Date of upload:
31.10.2015
Co-author:
Gabor Szekely (ETH Zurich), Andreas Schuppert (RWTH), Christian Stary (JKU), Stefan Oppl (JKU), Nils Meyer (Metasonic)
Abstract:
The vision of this paper is to bring together a team of biologists and from medicine regarding the definition of biomarkers with specialists of process or event modelling methodology to implement such biomarkers and with IT specialists of Ubiquitous Complex Event Processing of accordant real-time processing platforms for a tremendous vast amount of events or signals per second. In the final paper we will combine and transfer the process modelling approach based on the example of the THESEUS project jcpex! [??, http://theseusprogramm.de/en/936.php] with the U-CEP idea as discussed in this workshop series. A human body is actually a collaboration of around 50 or more trillion cells which do event processing and collaborating via the receptors of the cell membrane and the related effectors which “manage” or control the processes of a protein machinery. To model and control the event processing of specific biomarkers can be the basis to avoid and heal diseases. Especially interesting are the dynamic aspects of a not strongly fixed and in advance defined collaboration of processes. The processes can be combined dynamically as it is perhaps also typical in the fields of biology and medicine. This also includes the aspects of Uncertainty modeling as also mentioned in Ch. 5 of the VPH-FET roadmap.
Solar Physics Research Integrated Network Group Science Requirement Document
Natural Sciences (Astrophysics and Astrononmy)
Date of upload:
05.10.2016
Co-author:
Frank Hill, Sanjay Gosain, Alexei Pevtsov, Rekha Jain, Michal Sobotka, Illaria Ermolli
Abstract:
This document is deliverable D80.1 of the Solarnet Work Package 80. It is the Science Requirement Document for SPRING - a new network of ground-based observatories for synoptic observations of the sun. This document condesates the ideas of the four SPRING working groups: 1. Synoptic Magnetic Fields 2. Solar Seismology 3. Transient Events 4. Solar Awareness
A Comprehensive Approach to Privacy in the Cloud-based Internet of Things
Computer Sciences (Security and cryptography)
Date of upload:
10.01.2019
Co-author:
Lars Hermerschmidt, Daniel Kerpen, Roger Häußling, Bernhard Rumpe, Klaus Wehrle
Abstract:
In the near future, the Internet of Things is expected to penetrate all aspects of the physical world, including homes and urban spaces. In order to handle the massive amount of data that becomes collectible and to offer services on top of this data, the most convincing solution is the federation of the Internet of Things and cloud computing. Yet, the wide adoption of this promising vision, especially for application areas such as pervasive health care, assisted living, and smart cities, is hindered by severe privacy concerns of the individual users. Hence, user acceptance is a critical factor to turn this vision into reality. To address this critical factor and thus realize the cloud-based Internet of Things for a variety of different application areas, we present our comprehensive approach to privacy in this envisioned setting. We allow an individual user to enforce all her privacy requirements before any sensitive data is uploaded to the cloud, enable developers of cloud services to integrate privacy functionality already into the development process of cloud services, and offer users a transparent and adaptable interface for configuring their privacy requirements.
Inversions for Deep Solar Meridional Flow Using Spherical Born Kernels
Natural Sciences (Astrophysics and Astrononmy)
Date of upload:
28.07.2017
Co-author:
Markus Roth, Jason Jackiewicz, Shukur Kholikov
Abstract:
The solar meridional flow is a crucial ingredient in modern dynamo theory. Seismic estimates of this flow have, however, been contradictory in deeper layers below about $0.9\,R_\odot$. Results from time-distance helioseismology have so far been obtained using the ray approximation. Here, we perform inversions using the Born approximation. The initial result is similar to the result previously obtained by Jackiewicz et al. (2015) using ray kernels while using the same set of GONG data and the SOLA inversion technique. However, we show that the assumption of uncorrelated measurements used in earlier studies may lead to inversion errors being underestimated by a factor of about two to four. In a second step, refined inversions are performed using the full covariance matrix and a regularization for cross-talk. As the results are found to depend on the threshold used in the singular value decomposition, they were obtained for a medium threshold ($10^{−7} − 10^{−5}$, about 50% of the values used) and a threshold lower by a factor of 10 (about 70% of the values used). The result obtained with the medium threshold is again similar to the original, with less latitudinal variation. However, using the lower threshold, the inverted flow in the southern hemisphere shows two or three cells stacked radially depending on the associated radial flows. Both the single-cell and the multi-cell profiles are consistent with the measured travel times. All our results confirm a shallow return flow at about $0.9\,R_\odot$.
Seismology of the Sun and the Distant Stars 2016
Natural Sciences (Astrophysics and Astrononmy)
Start date:
10.07.2016
End date:
14.07.2016
Location:
Angra do Heroísmo, Terceira-Açores, Portugal
Towards a Multimodal Construction Grammar
Humanities (Linguistics)
Start date:
09.03.2016
End date:
11.03.2016
Location:
Osnabrück, Germany
Helicity Thinkshop 3
Natural Sciences (Astrophysics and Astrononmy)
Start date:
19.11.2017
End date:
24.11.2017
Location:
Tokyo (Japan)
Sun and Society
Natural Sciences (Astrophysics and Astrononmy)
Start date:
05.10.2020
End date:
09.10.2020
Location:

The Meeting will take place at Venice International University (VIU). VIU is something unique in the academic world, a consortium of 18 universities from all over the world with an autonomous campus on the island of San Servolo, Venice, Italy.  (Further information: http://www.univiu.org/index.php).

Regrettably, the 1st H2020-SOLARNET “Sun and Society” Meeting has been postponed due to the coronavirus (COVID-19) outbreak in Europe and worldwide.

A NEW DATE WILL BE ANNOUNCED AS SOON AS CONDITIONS PERMIT 

https://solarnews.nso.edu/h2020-solarnet-sun-and-society-meeting-postponed/

 

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