Autonomous reconfigurable intelligent surfaces through wireless energy harvesting

In this paper, we examine the potential for a reconfigurable intelligent surface (RIS) to be powered by energy harvested from information signals. This feature might be key to reap the benefits of RIS technology's lower power consumption compared to active relays. We first identify the main RIS power-consuming components and then propose an energy harvesting and power consumption model. Furthermore, we formulate and solve the problem of the optimal RIS placement together with the amplitude and phase response adjustment of its elements in order to maximize the signal-to-noise ratio (SNR) while harvesting sufficient energy for its operation. Finally, numerical results validate the autonomous operation potential and reveal the range of power consumption values that enables it.This work was supported by the European Commission’s Horizon 2020 research and innovation programme ARIADNE (No. 871464), the Luxembourg National Research Fund (FNR) under the CORE project RISOTTI (ref. 14773976), and the Digital Futures Center.Peer ReviewedPostprint (author's final draft

Uneventful Anterior Migration of Intravitreal Ozurdex Implant in a Patient with Iris-Sutured Intraocular Lens and Descemet Stripping Automated Endothelial Keratoplasty.

We report here the case of a patient with anterior segment migration of intravitreal dexamethasone implant as well as its management and outcome. The patient had the following sequence of events: complicated cataract surgery, iris-sutured intraocular lens implant, followed by cystoid macular edema treated with intravitreal Avastin, retinal vein occlusion treated with intravitreal dexamethasone implant, corneal decompensation treated with Descemet stripping automated endothelial keratoplasty (DSAEK), and finally recurrence of macular edema treated with repeated intravitreal dexamethasone implant. Dexamethasone implant had completely dissolved from the eye 12 weeks after insertion without any complication. A conservative approach with regular monitoring in the situation of a quiet anterior segment without any corneal decompensation can provide enough time for the implant to dissolve without causing any complication to the involved eye, avoiding any additional surgical intervention, as presented in this case report. Despite the fact that the implant was left for natural dissolution, there were no adverse effects related to the graft or the eye

D4.2 Intelligent D-Band wireless systems and networks initial designs

This deliverable gives the results of the ARIADNE project's Task 4.2: Machine Learning based network intelligence. It presents the work conducted on various aspects of network management to deliver system level, qualitative solutions that leverage diverse machine learning techniques. The different chapters present system level, simulation and algorithmic models based on multi-agent reinforcement learning, deep reinforcement learning, learning automata for complex event forecasting, system level model for proactive handovers and resource allocation, model-driven deep learning-based channel estimation and feedbacks as well as strategies for deployment of machine learning based solutions. In short, the D4.2 provides results on promising AI and ML based methods along with their limitations and potentials that have been investigated in the ARIADNE project

Autonomous Reconfigurable Intelligent Surfaces Through Wireless Energy Harvesting

In this paper, we examine the potential for a reconfigurable intelligent surface (RIS) to be powered by energy harvested from information signals. This feature might be key to reap the benefits of RIS technology's lower power consumption compared to active relays. We first identify the main RIS power-consuming components and then propose an energy harvesting and power consumption model. Furthermore, we formulate and solve the problem of the optimal RIS placement together with the amplitude and phase response adjustment of its elements in order to maximize the signal-to-noise ratio (SNR) while harvesting sufficient energy for its operation. Finally, numerical results validate the autonomous operation potential and reveal the range of power consumption values that enables it.This work was supported by the European Commission’s Horizon 2020 research and innovation programme ARIADNE (No. 871464), the Luxembourg National Research Fund (FNR) under the CORE project RISOTTI (ref. 14773976), and the Digital Futures Center.Peer ReviewedPostprint (author's final draft

Nonlinear imaging microscopy for assessing structural and photochemical modifications upon laser removal of dammar varnish on photosensitive substrates

The nonlinear optical microscopy (NLM) modalities of Multi-Photon Excited Fluorescence (MPEF) and Third Harmonic Generation (THG) have been combined in this work to characterize as a function of depth with micrometric resolution the type and extent of morphological and photochemical modifications that take place upon ultraviolet (UV) pulsed laser removal of a dammar varnish layer applied on a photosensitive substrate. The latter consists on a layer of the synthetic polymer polymethyl methacrylate doped with a photosensitizer, the aromatic compound 1,4-di[2-(5-phenyloxazolyl)] benzene, that strongly fluoresces upon UV light illumination. A number of laser conditions for partial or total elimination of the varnish coating were explored, namely different wavelengths (266, 248 and 213 nm) and pulse durations, in the nanosecond, picosecond and femtosecond ranges. Changes in the MPEF signals upon laser ablation of the outermost varnish layer successfully signpost photochemical modifications of the varnish or of the photosensitive under-layer, and their dependence with the laser ablation parameters, i.e., wavelength and pulse duration. In turn, THG signals mark the presence of layer boundaries and the reduction by laser ablation of the thickness of the varnish coating. The obtained MPEF and THG data are complemented by morphological observation by optical microscopy and measurements of laser induced fluorescence and micro-Raman spectra of the samples before and after laser ablation at the selected laser irradiation conditions. The results acquired through these nondestructive NLM imaging techniques serve to understand the phenomena that are induced upon laser ablation and to determine the best operating conditions that ensure controlled removal of the varnish with minimal morphological and chemical modifications to the under-layers. This research is of direct application to the UV pulsed laser cleaning of paintings and demonstrates the potential of NLM as a novel assessment tool for non-destructive, on line monitoring of the laser cleaning process.Peer reviewe

Lexical and structural biases in the acquisition of motion verbs

It is well known that languages differ in how they encode motion. Languages such as English use verbs that communicate the manner of motion (e.g., climb, float), while languages such as Greek often encode the path of motion in verbs (e.g., advance, exit). In two studies with English- and Greek-speaking adults and five year olds, we ask how such lexical constraints are used in combination with structural cues in hypothesizing meanings for novel motion verbs cross-linguistically. We show that lexicalization biases affect the interpretations of motion verbs in both young children and adults across different languages; furthermore, their scope of application is larger than previously thought, since they also extend to the domain of caused motion events. Crucially, we find that the language-specific effects of such biases interact with universal mappings between syntactic structure and semantic content. Finally, we demonstrate that the combined effects of lexical and structural cues shift nonlinguistic biases observed during event categorization: even though speakers of English and Greek share nonlinguistic preferences in categorizing spontaneous and caused motion, they focus on different components of motion events when building hypotheses about the meaning of novel motion verbs. © Taylor & Francis Group, LLC

Event categorisation and language: A cross-linguistic study of motion

It is well known that languages differ in how they encode motion. Languages such as English use verbs that communicate the manner of motion (e.g., slide, skip), while languages such as Greek regularly encode motion paths in verbs (e.g., enter, ascend). Here we ask how such cross-linguistic encoding patterns interface with event cognition by comparing labelling and categorisation preferences for motion events by English- and Greek-speaking adults and 5-year-olds. Our studies show that, despite cross-linguistic encoding differences, the categorisation of dynamically unfolding motion events proceeds in identical ways in members of these two linguistic communities. Nevertheless, language-congruent categorisation preferences emerge in tasks that implicitly encourage the use of linguistic stimuli during event apprehension. These data have implications for the relationship between language and event categorisation. © 2009 Psychology Press

The Source-Goal asymmetry in spatial language: language-general vs. language-specific aspects

Prior research has demonstrated a linguistic asymmetry between the sources and goals of motion events, with goals being mentioned more frequently compared to sources in motion descriptions by both children and adults. Here we explore the potency and features of this asymmetry comparing linguistic production data from children and adults who speak typologically different languages (English vs. Greek). We show that the asymmetry is robust cross-linguistically and can therefore plausibly be considered a shared, potentially universal feature of spatial language. However, the Source-Goal asymmetry does not surface uniformly across different morphosyntactic devices (verbs vs. adpositions) used to encode motion across languages. Thus a shared bias in spatial language interacts with language-specific aspects of spatial encoding. © 2019, © 2019 Informa UK Limited, trading as Taylor & Francis Group