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Word Ladders is a free mobile application for Android and iOS, developed for collecting linguistic data, specifically lists of words related to each other through semantic relations of categorical inclusion, within the Abstraction project (ERC-2021-STG-101039777). We hereby provide an overview of Word Ladders, explaining its game logic, motivation and expected results and applications to nlp tasks as well as to the investigation of cognitive scientific open questions

A collection of more than 1800 carbonized Greek and Latin papyri, discovered in the Roman Villa dei Papiri at Herculaneum in the middle of 18th century, is the unique classical library survived from antiquity. These ancient-Herculaneum-papyri were charred during 79 A.D. Vesuvius eruption, a circumstance which providentially preserved them until now. This magnificent collection contains valuable work by Greek philosophers, such as Epicurus, Chrysippus and Philodemus, in particular an impressive amount of extensive treatises by Philodemus of Gadara, an Epicurean philosopher of the 1st century BC. The aim of the present study is to read extended and hitherto unknown portions of text hidden inside carbonized-Herculaneum-papyri using enhanced X-ray-phase-contrast-tomography (XPCT) non-destructive technique and a new set of numerical algorithms for virtual-unrolling. This paper documents our success in revealing the largest portion of Greek text ever detected so far inside unopened scrolls, with unprecedented spatial resolution and contrast, all without damaging these precious historical manuscripts. Parts of texts have been decoded and the 'voice' of Epicurean philosopher Philodemus is brought back again after 2000 years from rolled-up carbonized Herculaneum-papyri.

We have used a combination of resonant magnetic x-ray scattering (RMXS) and x-ray absorption spectroscopy (XAS) to investigate the properties of the doped spin-orbital Mott insulator Sr2Ir(1-x)Rh(x)O4 (0.07 < x < 0.70). We show that Sr2Ir(1-x)Rh(x)O4 represents a unique model system for the study of dilute magnetism in the presence of strong spin-orbit coupling, and provide evidence of a doping-induced change in magnetic structure and a suppression of magnetic order at x_c ~ 0.17. We demonstrate that Rh-doping introduces Rh3+/Ir5+ ions which effectively hole-dope this material. We propose that the magnetic phase diagram for this material can be understood in terms of a novel spin-orbital percolation picture., Comment: 9 pages, 7 figures

We report comprehensive synchrotron x-ray scattering and magnetic susceptibility studies of the doped spin-Peierls materials Cu_{1-x}Zn_xGeO_3 and CuGe_{1-y}Si_yO_3. Temperature versus dopant concentration phase diagrams are mapped out for both Zn and Si dopants. The phase diagrams of both Cu_{1-x}Zn_xGeO_3 and CuGe_{1-y}Si_yO_3 closely resemble that of Cu_{1-x}Mg_xGeO_3, including the observation that the spin gap is established at a much higher temperature than the temperature at which the spin-Peierls dimerization attains long-range order. The spin-Peierls transitions in doped samples exhibit unusual phase transition behavior, characterized by highly rounded phase transitions, Lorentzian squared lineshapes, and very long relaxation times. Phenomenological explanations for these observations are given by considering the effects of competing random bond interactions as well as random fields generated by the dopants. We have also confirmed the reentrance of the spin-Peierls phase when the temperature is lowered through the antiferromagnetic ordering transition. The low temperature re-entrance of the spin-Peierls phase has been explained speculatively using a local phase separation scheme between the spin-Peierls phase and the Neel phase., Comment: 12 pages, 13 figures, submitted version, substantial rewriting and rearranged figures

The critical fluctuations of CuGeO$_3$ have been measured by synchrotron x-ray scattering, and two length scales are clearly observed. The ratio between the two length scales is found to be significantly different along the $a$ axis, with the $a$ axis along the surface normal direction. We believe that such a directional preference is a clear sign that surface random strains, especially those caused by dislocations, are the origin of the long length scale fluctuations., Comment: 5 pages, 4 figures, submitted to PRB

We report a synchrotron x-ray scattering study of the diluted spin-Peierls (SP) material Cu_{1-x}Mg_xGeO_3. In a recent paper we have shown that the SP dimerization attains long-range order only for x < x_c = 0.022(0.001). Here we report that the SP transition is reentrant in the vicinity of the critical concentration x_c. This is manifested by broadening of the SP dimerization superlattice peaks below the reentrance temperature, T_r, which may mean either the complete loss of the long-range SP order or the development of a short-range ordered component within the long-range ordered SP state. Marked hysteresis and very large relaxation times are found in the samples with Mg concentrations in the vicinity of x_c. The reentrant transition is likely related to the competing Neel transition which occurs at a temperature similar to T_r. We argue that impurity-induced competing interchain interactions play an essential role in these phenomena., Comment: 5 pages, 4 embedded eps figures

Tomorrow's Interplanetary Network (IPN) will evolve from JPL's Deep-Space Network (DSN) and provide key capabilities to future investigators, such as simplified acquisition of higher-quality science at remote sites and enriched access to these sites. These capabilities could also be used to foster public interest, e.g., by making it possible for students to explore these environments personally, eventually perhaps interacting with a virtual world whose models could be populated by data obtained continuously from the IPN. Our paper looks at JPL's approach to making this evolution happen, starting from improved communications. Evolving space protocols (e.g., today's CCSDS proximity and file-transfer protocols) will provide the underpinning of such communications in the next decades, just as today's rich web was enabled by progress in Internet Protocols starting from the early 1970's (ARPAnet research). A key architectural thrust of this effort is to deploy persistent infrastructure incrementally, using a layered service model, where later higher-layer capabilities (such as adaptive science planning) are enabled by earlier lower-layer services (such as automated routing of object-based messages). In practice, there is also a mind shift needed from an engineering culture raised on point-to-point single-function communications (command uplink, telemetry downlink), to one in which assets are only indirectly accessed, via well-defined interfaces. We are aiming to foster a 'community of access' both among space assets and the humans who control them. This enables appropriate (perhaps eventually optimized) sharing of services and resources to the greater benefit of all participants. We envision such usage to be as automated in the future as using a cell phone is today - with all the steps in creating the real-time link being automated.

This slide presentation reviews the application of middleware in space exploration, and satellite communications. The aim of the use of Space middleware is ot use remote sensors and other resources more efficiently.

This paper describes middleware systems developed at JPL, shows how leveraging middleware implementation strategies can facilitate building a mission operations system for managing multiple interacting missions on Mars, and proposes an approach to implementing demonstrations as part of a roadmap providing progressively more intelligent remote exploration.

A web-based interface has recently been added to an advanced integrated environment being developed at JPL that links collaborators who wish to perform interactive design analyses and/or mission simulations.

An advanced integrated environment is being developed at JPL that links collaborators who wish to perform interactive design analyses and/or mission simulations.

(view graph) NASA lead center for robotic space exploration. Operating division of Caltech/Jet Propulsion Laboratory. Current missions, Voyagers, Galileo, Pathfinder, Global Surveyor. Upcoming missions, Cassini, Mars and New Millennium.