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Am Beispiel der industriellen Tankreinigung wird in diesem Beitrag ein cyberphysisch-adaptives Reinigungssystem skizziert, welches selbstlernend eine kontinuierliche Optimierung des Prozesses vornimmt. Es werden die drei wesentlichen Bausteine für ein solches adaptives System beleuchtet: Sensorik, Robotik und Software. Neuartige Inline-Sensorik liefert erstmalig genügend Prozessinformationen, um durch eine intelligente Software analysiert und in bedarfsgerechte Reinigungsprozesse abgeleitet zu werden. Innovative robotische Reinigungssysteme bieten endlich die notwendigen Freiheitsgrade, um überhaupt in der Lage zu sein, diese adaptiven Reinigungsanforderungen in reale Reinigungsvorgänge zu übersetzen.

During the past few years, the Goddard Earth Observing System (GEOS) and Massachusetts Institute of Technology general circulation model (MITgcm) groups have produced, respectively, global atmosphere-only and ocean-only simulations with km-scale grid spacing. These simulations have proved invaluable for process studies and the development of satellite and in-situ sampling strategies. Nevertheless, a key limitation of these simulations is the lack of feedback between the ocean and the atmosphere, limiting their usefulness for studying air-sea interactions and designing observing missions to study these interactions. To remove this limitation, we have coupled the km-scale GEOS atmospheric model with the km-scale MITgcm ocean model. We will present preliminary results from the GEOS-MITgcm contribution to the second phase of the DYAMOND (DYnamics of the Atmospheric general circulation Modeled On Non-hydrostatic Domains) initiative.The coupled atmosphere-ocean simulation was integrated using a cubed-sphere-1440 (~6-7 km horizontal grid spacing) configuration of GEOS and a lat-lon-cap-2160 (2–5-km horizontal grid spacing) configuration of MITgcm. We will show results from a preliminary analysis of air-sea interactions between Sea Surface Temperature (SST) and surface winds. In particular, we will discuss non-local atmospheric overturning circulation formed above the Gulf Stream SST front with characteristic sub-mesoscale width. This formation of a secondary circulation above the front suggests that capturing such air-sea interaction phenomena requires high-resolution capabilities in both the models' oceanic and atmospheric components.

We present 2,241 exoplanet candidates identified with data from the Transiting Exoplanet Survey Satellite (TESS) during its two-year prime mission. We list these candidates in the TESS Objects of Interest (TOI) Catalog, which includes both new planet candidates found by TESS and previously-known planets recovered by TESS observations. We describe the process used to identify TOIs and investigate the characteristics of the new planet candidates, and discuss some notable TESS planet discoveries. The TOI Catalog includes an unprecedented number of small planet candidates around nearby bright stars, which are well-suited for detailed follow-up observations. The TESS data products for the Prime Mission (Sectors 1-26), including the TOI Catalog, light curves, full-frame images, and target pixel files, are publicly available on the Mikulski Archive for Space Telescopes., Comment: 39 pages, 16 figures. The Prime Mission TOI Catalog is included in the ancillary data as a CSV. For the most up-to-date catalog, refer to https://tess.mit.edu/toi-releases/

We report the discovery of an Earth-sized planet in the habitable zone of a low-mass star called Kepler-1649. The planet, Kepler-1649 c, is 1.06$^{+0.15}_{-0.10}$ times the size of Earth and transits its 0.1977 +/- 0.0051 Msun mid M-dwarf host star every 19.5 days. It receives 74 +/- 3 % the incident flux of Earth, giving it an equilibrium temperature of 234 +/- 20K and placing it firmly inside the circumstellar habitable zone. Kepler-1649 also hosts a previously-known inner planet that orbits every 8.7 days and is roughly equivalent to Venus in size and incident flux. Kepler-1649 c was originally classified as a false positive by the Kepler pipeline, but was rescued as part of a systematic visual inspection of all automatically dispositioned Kepler false positives. This discovery highlights the value of human inspection of planet candidates even as automated techniques improve, and hints that terrestrial planets around mid to late M-dwarfs may be more common than those around more massive stars., Comment: 11 pages, 3 figures, 1 table. Accepted for publication in ApJL

The Transiting Exoplanet Survey Satellite, TESS, is currently carrying out an all-sky search for small planets transiting bright stars. In the first year of the TESS survey, steady progress was made in achieving the mission's primary science goal of establishing bulk densities for 50 planets smaller than Neptune. During that year, TESS's observations were focused on the southern ecliptic hemisphere, resulting in the discovery of three mini-Neptunes orbiting the star TOI-125, a V=11.0 K0 dwarf. We present intensive HARPS radial velocity observations, yielding precise mass measurements for TOI-125b, TOI-125c and TOI-125d. TOI-125b has an orbital period of 4.65 days, a radius of $2.726 \pm 0.075 ~\mathrm{R_{\rm E}}$, a mass of $ 9.50 \pm 0.88 ~\mathrm{M_{\rm E}}$ and is near the 2:1 mean motion resonance with TOI-125c at 9.15 days. TOI-125c has a similar radius of $2.759 \pm 0.10 ~\mathrm{R_{\rm E}}$ and a mass of $ 6.63 \pm 0.99 ~\mathrm{M_{\rm E}}$, being the puffiest of the three planets. TOI-125d, has an orbital period of 19.98 days and a radius of $2.93 \pm 0.17~\mathrm{R_{\rm E}}$ and mass $13.6 \pm 1.2 ~\mathrm{M_{\rm E}}$. For TOI-125b and TOI-125d we find unusual high eccentricities of $0.19\pm 0.04$ and $0.17^{+0.08}_{-0.06}$, respectively. Our analysis also provides upper mass limits for the two low-SNR planet candidates in the system; for TOI-125.04 ($R_P=1.36 ~\mathrm{R_{\rm E}}$, $P=$0.53 days) we find a $2\sigma$ upper mass limit of $1.6~\mathrm{M_{\rm E}}$, whereas TOI-125.05 ( $R_P=4.2^{+2.4}_{-1.4} ~\mathrm{R_{\rm E}}$, $P=$ 13.28 days) is unlikely a viable planet candidate with upper mass limit $2.7~\mathrm{M_{\rm E}}$. We discuss the internal structure of the three confirmed planets, as well as dynamical stability and system architecture for this intriguing exoplanet system., Comment: Accepted for publication in MNRAS

The Wide-Field Infrared Survey Telescope (WFIRST) is planned to have a coronagraphic instrument (CGI) to enable high-contrast direct imaging of exoplanets around nearby stars. The majority of nearby FGK stars are located in multi-star systems, including the Alpha Centauri stars which may represent the best quality targets for the CGI on account of their proximity and brightness potentially allowing the direct imaging of rocky planets. However, a binary system exhibits additional leakage from the off-axis companion star that may be brighter than the target exoplanet. Multi-Star Wavefront Control (MSWC) is a wavefront-control technique that allows suppression of starlight of both stars in a binary system thus enabling direct imaging of circumstellar planets in binary star systems such as Alpha Centauri. We explore the capabilities of the WFIRST CGI instrument to directly image multi-star systems using MSWC. We consider several simulated scenarios using the WFIRST CGI's Shaped Pupil Coronagraph (SPC) Wide-Field Imaging Mode. First, we consider close binaries such as Mu Cassiopeia that require no modifications to the WFIRST CGI instrument and can be implemented as a purely algorithmic solution. Second, we consider wide binaries such as Alpha Centauri that require a diffraction grating to enable suppression of the off-axis starlight leakage at Super-Nyquist separations. We demonstrate via simulation dark holes in 10% broadband compatible with the WFIRST CGI.

We describe a concurrent visualization pipeline designed for operation in a production supercomputing environment. The facility was initially developed on the NASA Ames "Columbia" supercomputer for a massively parallel forecast model (GEOS4). During the 2005 Atlantic hurricane season, GEOS4 was run 4 times a day under tight time constraints so that its output could be included in an ensemble prediction that was made available to forecasters at the National Hurricane Center. Given this time-critical context, we designed a configurable concurrent pipeline to visualize multiple global fields without significantly affecting the runtime model performance or reliability. We use MPEG compression of the accruing images to facilitate live low-bandwidth distribution of multiple visualization streams to remote sites. We also describe the use of our concurrent visualization framework with a global ocean circulation model, which provides a 864-fold increase in the temporal resolution of practically achievable animations. In both the atmospheric and oceanic circulation models, the application scientists gained new insights into their model dynamics, due to the high temporal resolution animations attainable.

Systematists and comparative biologists commonly want to make statements about relationships among taxa that have never been collectively included in any single phylogenetic analysis. Construction of phylogenetic 'supertrees' provides one solution. Supertrees are estimates of phylogeny assembled from sets of smaller estimates (source trees) sharing some but not necessarily all their taxa in common. If certain conditions are met, supertrees can retain all or most of the information from the source trees and also make novel statements about relationships of taxa that do not co-occur on any one source tree. Supertrees have commonly been constructed using subjective and informal approaches, but several explicit approaches have recently been proposed.

Numerical studies of an apparently stable knotted singularity are used here to seek out regularities of vortex dynamics in three-dimensional excitable media. Initial conditions were contrived to produce a vortex filament in the form of a trefoil (3:2 torus) knot, using the piecewise linear 'B-kinetics', with excitability parameter 'g' set to 0.9. The simulation was pursued for 3000 time units, or about 125 wave rotations, during which time the knot was observed to rigidly 'precess' about its symmetry axis, completing one turn every 96 wave rotations, and also translate along that same axis, at about 1 percent of wavespeed. These motions, described with respect to the local Frenet frame, were shown to be highly correlated with local geometry and twist, yielding possible 'laws of filament motion', which might prove viable in other contexts. The trefoil knot is the first organizing center to be studied in detail which exhibits nonuniform twist, and its dynamical behavior supports the notion that the arclength derivative of twist is an important determinant of filament motion, first postulated by Keener in 1988. The knot also exhibited changes in twist distribution, and, to a lesser extent, local geometry, within one wave rotation period, adding an unforeseen complication to efforts at understanding vortex dynamics. The knot is compact, only about a wavelength in radius, so filament interactions may play a prominent role in determining the stability and behavior of the object. The locus of wave collisions was determined for the knot; in places this surface apparently adjoins the filament itself. In the course of this study, two different criteria for locating the filament were compared, and many analytic and graphical utilities were developed, which may prove useful in further studies of three-dimensional excitable media.

Estimates of ocean circulation constrained by in situ and remotely sensed observations have become routinely available during the past five years, and they are being applied to myriad scientific and operational problems [Stammer et al.,2002]. Under the Global Ocean Data Assimilation Experiment (GODAE), several regional and global estimates have evolved for applications in climate research, seasonal forecasting, naval operations, marine safety, fisheries,the offshore oil industry, coastal management, and other areas. This article reports on recent progress by one effort, the consortium for Estimating the Circulation and Climate of the Ocean (ECCO), toward a next-generation synthesis of ocean and sea-ice data that is global, that covers the full ocean depth, and that permits eddies.

A ‘third generation’ cellular automaton (CA) model of excitable media, introduced in 1992 by Weimar, Tyson and Watson (Physica D, 1992, 55, 309; 328) is extended to three spatial dimensions (3D). Diffusion is described by 3D Gaussian masks and the update rules are devised to mimic the FitzHugh–Nagumo partial differential equations (PDEs) of excitability. The CA is intended to explore the properties of rotating scroll waves. 3D domains of several λ3(λ= wavelength of scroll) can be simulated by the CA on a typical desktop workstation, and larger domains are suitable for parallel processing by methods described. The accuracy and performance of the CA, as a simulation tool for continuous excitable media, are assessed by comparing CA and PDE results for scroll waves of various geometries and parameters.

A dynamical system that can be provoked by a small stimulus to execute a large transient excursion before returning to the original state is called 'excitable'. In the Belousov–Zhabotinsky (BZ) reagent1 such excitation propagates as a travelling pulse of oxidative activity; leaving a point source, it resembles a closed spherical surface. Activity in excitable media can also be self-organized, independent of any recent stimulus. Wavefronts in cross-section then resemble a spiral emanating from a central pivot. In three dimensions the pivot points form a line, a vortex filament, that typically closes in a slowly shrinking 'scroll ring' (Fig. l)2–4. Here we report the results of monitoring this shrinkage quantitatively both in the BZ reagent and in the Oregonator model, leading to the confirmation of mathematical arguments that derive the filament's motion from its local curvature5–8. By additionally observing the predicted rapid unwinding of a coiled vortex filament9 we validate the reaction–diffusion theory of self-organized activity in such excitable media.

We announce the discovery of GPX-1 b, a transiting brown dwarf with a mass of $19.7\pm 1.6$ $M_{\mathrm{Jup}}$ and a radius of $1.47\pm0.10$ $R_{\mathrm{Jup}}$, the first sub-stellar object discovered by the Galactic Plane eXoplanet (GPX) survey. The brown dwarf transits a moderately bright ($V$ = 12.3 mag) fast-rotating F-type star with a projected rotational velocity $v\sin{ i_*}=40\pm10$ km/s. We use the isochrone placement algorithm to characterize the host star, which has effective temperature $7000\pm200$ K, mass $1.68\pm0.10$ $M_{\mathrm{Sun}}$, radius $1.56\pm0.10$ $R_{\mathrm{Sun}}$ and approximate age $0.27_{-0.15}^{+0.09}$ Gyr. GPX-1 b has an orbital period of $\sim$1.75 d, and a transit depth of $0.90\pm0.03$ %. We describe the GPX transit detection observations, subsequent photometric and speckle-interferometric follow-up observations, and SOPHIE spectroscopic measurements, which allowed us to establish the presence of a sub-stellar object around the host star. GPX-1 was observed at 30-min integrations by TESS in Sector 18, but the data is affected by blending with a 3.4 mag brighter star 42 arcsec away. GPX-1 b is one of about two dozen transiting brown dwarfs known to date, with a mass close to the theoretical brown dwarf/gas giant planet mass transition boundary. Since GPX-1 is a moderately bright and fast-rotating star, it can be followed-up by the means of Doppler tomography., 13 pages, 13 figures, accepted to MNRAS in May 2021

The Transiting Exoplanet Survey Satellite (\textit{TESS}) mission was designed to perform an all-sky search of planets around bright and nearby stars. Here we report the discovery of two sub-Neptunes orbiting around the TOI 1062 (TIC 299799658), a V=10.25 G9V star observed in the TESS Sectors 1, 13, 27 & 28. We use precise radial velocity observations from HARPS to confirm and characterize these two planets. TOI 1062b has a radius of 2.265^{+0.095}_{-0.091} Re, a mass of 11.8 +\- 1.4 Me, and an orbital period of 4.115050 +/- 0.000007 days. The second planet is not transiting, has a minimum mass of 7.4 +/- 1.6 Me and is near the 2:1 mean motion resonance with the innermost planet with an orbital period of 8.13^{+0.02}_{-0.01} days. We performed a dynamical analysis to explore the proximity of the system to this resonance, and to attempt at further constraining the orbital parameters. The transiting planet has a mean density of 5.58^{+1.00}_{-0.89} g cm^-3 and an analysis of its internal structure reveals that it is expected to have a small volatile envelope accounting for 0.35% of the mass at maximum. The star's brightness and the proximity of the inner planet to the "radius gap" make it an interesting candidate for transmission spectroscopy, which could further constrain the composition and internal structure of TOI 1062b., 14 pages, 11 figures